В 2012 г. правительство Ямало-Ненецкого округа совместно с НИИ Арктики и Антарктики Росгидромета провело первую комплексную экспедицию по обследованию полуострова Ямал (КАЭМБ Ямал-Арктика 2012). Ключевыми участками наблюдений стали пос. Новый Порт, пос. Усть Юрибей и о-в Белый. К последнему участку сейчас привлечено максимальное внимание общественности, поскольку он выбран для начала осуществления программы по очистке Арктики от мусора и отходов, накопившихся в процессе функционирования полярной инфраструктуры. Пробы почв были отобраны из шурфов в августе 2012 г. Тяжелые металлы, а также содержание оксидов кремния, алюминия, железа, титана, марганца определялись на рентгенфлуоресцентном анализаторе «Спектроскан-МАКС». Полученные значения сопоставлялись с ОДК и ПДК принятыми в РФ. Так как накопление тяжелых металлов связано с их фиксацией органическим веществом почв, параллельно производилась оценка содержания органического углерода и азота на приборе VARIO EL III. Применение профильного подхода к изучению химического состава почв помогло установить среднеглубинные и глубокие надмерзлотные максимумы накопления приоритетных неорганических токсикантов и других тяжелых металлов. Это связано, скорее всего, с развитием двух групп почвенных процессов: элювиально-иллювиальных и криогенного массообмена. В результате элювиально-иллювиальных процессов некоторые тяжелые металлы перераспределяются по профилю, аккумулируясь в средней части профиля. Между тем в тундровых почвах доминирующими являются процессы криогенного массобмена, приводящие к сильному перемешиванию почвенной толщи и накоплению некоторых компонентов химического состава в надмерзлотном или надмерзлотно-глеевом горизонте. Это главная причина второго максимума содержания тяжелых металлов в нижней части профилей почв. Проведенные исследования показывают, что, хотя чаще всего тяжелые металлы аккумулируются в верхних горизонтах почв, в случае тундровых почв процессы профильного перераспределения приводят к тому, что при поверхностном отборе проб происходит недооценка общих запасов веществ в почвенном профиле. ; In 2012, for the first time the Government of the Yamal-Nenets region in conjunction with the Arctic and Antarctic Research Institute ofRosHydromet, performed the first comprehensive expedition for the examination of the Yamal Peninsula (KAEMB Arctic Yamal-2012). As key observation plots there were selected: settlement Novy Port, Ust Yuribey and the Island Bely. To the last section now there is attracted the maximum attention of the public, because it is selected for the starting of the program for the cleaning up Arctic from the debris and the wastes accumulated during the process of the functioning ofpolar infrastructure. Soil samples were selected from the prospecting pits in August, 2012. Heavy metals, as well as the content of oxides of silicon, aluminum, iron, titanium, manganese were detected with X-ray fluorescent analyzer «Spectroscan-MAX. The values obtained were compared with the Approxible Permissible Concentrations and Maximum Allowable Concentrations adopted in Russia. Since the accumulation of heavy metals is related with their fixation by soil organic matter, concomitantly there was evaluated the content of organic carbon and nitrogen with the use of the device VARIO EL III. The application of the profile approach to the study of the chemical composition of soils helped to establish mid-ground and deep supra permafrost accumulation maximums of priority inorganic toxicants and other heavy metals. This is most likely related to the development of two groups of soil processes: eluvial-illuvial and cryogenic mass exchange. As a result of the eluvial-illuvial processes, some heavy metals are redistributed along the profile, and accumulating in the middle part of the profile. Meanwhile, in the tundra soils dominant processes are cryogenic mass exchange, leading to a strong mixing of the soil column and the accumulation of certain components in the chemical composition in the supra permafrost or suprapermafrostgley horizon. This is the main reason for the second peak of the content of heavy metals in the bottom of the soil profiles. Performed studies show that although most heavy metals are accumulated in the upper soil horizons, in the case of tundra, soil profile redistribution processes lead to the fact that in the case of the surface sampling, there is underestimation of the total reserves of substances in the soil profile.
Memoria presentada por Beatriz Sánchez Page, graduada en Química y Máster en Química Molecular y Catálisis Homogénea, para optar al grado de Doctor en Ciencias, en el programa de Doctorado en Química Inorgánica. Esta Tesis Doctoral se presenta en la modalidad de Tesis por compendio de publicaciones. ; [ES]: El trabajo desarrollado en esta Memoria se ha centrado en el diseño, síntesis, caracterización y estudios de estabilidad de compuestos moleculares de rodio e iridio soportados en materiales nanoestructurados de carbono. La actividad catalítica de los nuevos materiales híbridos y la de los complejos moleculares relacionados de rodio e iridio se ha evaluado en la hidrosililación de alquinos y en la oxidación química y electroquímica de agua, respectivamente. Los complejos de rodio(I) y (III) soportados en un óxido de grafeno reducido térmicamente a 400 ºC por enlace covalente carbono-nitrógeno entre un ligando NHC mesoiónico (4-fenil-3-metil-1,2,3-triazol-5-ilideno) y la pared del grafeno, Rh(I)/Rh(III)-NHC@TRGO, y los complejos moleculares relacionados muestran alta actividad en la hidrosililación de alquinos y una excelente regio- y estereoselectividad al isómero cinético β-(Z)-vinilsilano. Concretamente, el catalizador ciclometalado [Cp*RhI(C,C')-Triaz] (Triaz = 1,4-difenil-3-metil-1,2,3-triazol-5-ilideno) es un catalizador sobresaliente en la hidrosililación de alquinos terminales, alifáticos y aromáticos, a temperatura ambiente con completa regio- y estereoselectividad al isómero β(Z)-vinilsilano. Por otro lado, aunque el catalizador híbrido relacionado de rodio(III)-triazolilideno no es activo a temperatura ambiente, muestra la misma actividad y selectividad que el catalizador homogéneo a 60 °C. Adicionalmente, los catalizadores híbridos basados en grafeno modificado Rh-NHC@TRGO son completamente reciclables en la hidrosililación de alquinos con excelente control de la selectividad β-(Z). Los estudios por DFT del mecanismo de hidrosililación para el catalizador molecular de Rh(III) evidencian la posible participación de un mecanismo bifuncional metal-ligando basado en una ciclometalación reversible. Los materiales híbridos basados en complejos Ir(I)-NHC anclados a nanotubos de carbono a través de grupos éster, Ir(I)-NHC@CNT, son catalizadores eficientes en la oxidación química y electroquímica de agua. El estudio ha revelado que tanto los catalizadores moleculares homogéneos como los heterogéneos que poseen un ligando NHC funcionalizado con un grupo sulfonato son mucho más activos que los catalizadores moleculares relacionados con ligandos NHC no hidrosolubles, tanto en la oxidación química de agua, con CAN como oxidante de sacrificio, como en la oxidación electroquímica en la que se alcanzan valores de TOF de hasta 22000 h-1 a 1.4 V para el catalizador híbrido NHC-sulfonato. Por otro lado, se ha observado que la estructura grafítica del soporte juega un papel importante en el rendimiento electrocatalítico de oxidación de agua con complejos de iridio(I)-NHC soportados por enlace carbonato a dos óxidos de grafeno de diferente estructura grafítica. Se ha comprobado que el desplazamiento del ligando cloruro en los centros metálicos de iridio por grupos oxigenados de la pared nanoestructurada del grafeno tiene un impacto negativo en la actividad electrocatalítica del catalizador híbrido resultante. ; [EN]: The work developed in this Memory has been focused on the design, synthesis, characterization and stability studies of rhodium and iridium molecular compounds supported on carbon nanostructured materials. The catalytic activity of the new hybrid materials together and that of related molecular complexes of rhodium and iridium has been evaluated in the hydrosilylation of alkynes and in the chemical and electrochemical water oxidation, respectively. Rhodium(I) and (III) complexes supported on a thermally reduced graphene oxide at 400 °C by carbon‐nitrogen covalent bond between a mesoionic NHC ligand (4‐phenyl‐3‐methyl‐1,2,3‐triazole‐5‐ylidene) and the graphene wall, Rh(I)/Rh(III)‐NHC@TRGO, and related molecular complexes show high catalytic activity in hydrosilylation of alkynes with excellent regio‐ and stereoselectivity to the kinetic β‐(Z) vinylsilane isomer. Remarkably, the cyclometalated catalyst [Cp*RhI(C,C')‐Triaz] (Triaz = 1,4‐diphenyl‐3‐methyl‐1,2,3‐triazol‐5‐ylidene) shows an outstanding performance in the hydrosilylation of terminal, aliphatic and aromatic, alkynes with various hydrosilanes at room temperature with full regio‐ and stereoselectivity to β‐(Z)‐vinylsilanes. On the other hand, the related rhodium(III) triazolylidene hybrid catalyst is not active at room temperature although it shows an excellent catalytic performance at 60 °C. In addition, the hybrid catalysts based on modified graphene, Rh‐NHC@TRGO, are fully recyclable in alkyne hydrosilylation with excellent β-(Z) selectivity control. DFT studies on the alkyne hydrosilylation mechanism by the Rh(III) molecular catalyst point to the possible participation of a bifunctional metal‐ligand mechanism based on a reversible cyclometalation. The hybrid materials based on Ir(I)‐NHC complexes covalent attached to carbon nanotubes through ester functions, Ir(I)‐NHC@CNT, are efficient chemical and electrochemical water oxidation catalysts. The study has revealed that both homogeneous and heterogeneous molecular catalysts featuring NHC ligands functionalized with a sulfonate group are much more active than the related molecular catalysts lacking hydrosoluble NHC ligands, both in water chemical oxidation, using CAN as a sacrificial oxidant, or in electrochemical oxidation with TOF values up to 22000 h‐1 at 1.4 V for the sulfonate functionalized hybrid catalyst. On the other hand, it has been observed that the graphitic structure of the supports plays an important role in the water oxidation electrocatalytic performance of Ir(I)‐NHC complexes supported by carbonate bonding to two graphene oxides with different graphitic structure. A negative impact on the electrocatalytic activity has been found for the hybrid catalysts where the chloride ligand in the coordination sphere of the iridium metal centers has been displaced by oxygenated groups on the graphene nanostructured wall. ; Projects CTQ2016-75884-P, RTI2018-098537-B-C22, PID2019-103965GB-100, CTQ2013-42532-P and the Regional Governments of Aragón/FEDER/DGA 2014-2020 "Building Europe from Aragón" (groups E42_17R and E12_17R) and Principado de Asturias (FEDER: IDI/2018/000121). ; Peer reviewed
Die vorliegende Arbeit befasst sich mit der Synthese und Charakterisierung von nanostrukturierten Mikropartikelpulvern mit einstellbarem Zerfalls- und Dispergierungsverhalten und deren Anwendung als verstärkender Füllstoff sowie deren Eignung für Sensoranwendungen. Sie ist in drei Teilbereiche gegliedert: Der erste Teil beschreibt die Synthese der nanostrukturierten Mikropartikelpulvern durch Sprühtrocknung von kolloidalen oxidischen (silicatischen und eisenoxidischen) Nanopartikeln. Es wird ausgeführt, wie durch Variation der Art und Größe der Primärpartikel und deren mengenanteiligen Kombination Mikropartikel unterschiedlichster nanostruktureller Maserung und Ausprägung erhalten wurden. Das Spektrum dieser Partikel reichte von homogen verteilten Strukturen bis hin zu Kern-Satellit-Struktur, von kontrollierter Aggregierung bis hin zur vollständigen Dispergierbarkeit. Im zweiten Teil der Arbeit wurden die Partikel im Hinblick auf ihre Eignung und Verwendung als Füllstoffe für Elastomer-Matrices untersucht. Im Fokus stand die Verstärkungswirkung und die Korrelation mit dem Dispergierverhalten in PDMS. Im dritten Teil der Arbeit wurde das Syntheseprinzip der Herstellung nanostrukturierter Mikropartikel auf Hydroxid-basierte Systeme wie LDHs erweitert. Teil I: Von Silica-NP zu nanostrukturierten Mikropartikeln mit einstellbarem Zerfallsverhalten Um nanostrukturierte Mikropartikel mit einem integrierten Zerfallsverhalten zu erzeugen, wurden zunächst kolloidale Silica-NP mit einer Größe von 20 nm abgestuft mit unterschiedlichen Mengen (0, 1/10, 1/5, 1/3, 1/2, 2/3, 1) eines hydrophobierend wirkenden Silans (Triethoxyoctylsilan, OCTEO) modifiziert. Neben den beiden Extremen der vollständigen und unmodifizierten Varianten (1 und 0) wurden teilweise modifizierte Zwischenstufen erhalten, indem die Silanmenge auf 2/3, 1/2, 1/3, 1/5 und 1/10 im Vergleich zu den vollmodifizierten Silica-NP verringert wurde. Die modifizierten Nanopartikel zeigten beim Dispergieren in verschiedenen Flüssigkeiten (Wasser, Toluol) eindeutige und graduell klar differenzierbare Unterschiede in Abhängigkeit vom Bedeckungsgrad der Partikeloberfläche mit dem Silan. Wie erwartet nahm das hydrophobe Verhalten der Nanopartikel mit zunehmendem Bedeckungs- und damit Modifizierungsgrad zu und die Nanopartikel waren in unpolaren Flüssigkeiten wie Toluol gut dispergierbar, während sie in polaren Flüssigkeiten wie Wasser zur Agglomeration und Sedimentation neigten. In einem nächsten Schritt wurden die zu unterschiedlichen Graden mit OCTEO modifizierten kolloidalen Silica-NP mittels Sprühtrocknung in mikroskalige Pulver überführt. Die nanostrukturierten Mikropartikelpulver wurden mit verschiedenen Analysemethoden wie REM-Aufnahmen, BET-, FTIR- und TG-Messungen untersucht, und die Eigenschaften der gebildeten Partikel charakterisiert. Die nanostrukturierten Mikropartikel zeigten auf den REM-Aufnahmen abhängig vom Modifizierungsgrad der Nanopartikel ein sehr unterschiedliches Aussehen. Während die Mikropartikel aus vollständig modifizierten Nanopartikeln eine eher raue Oberfläche besaßen, hatten die aus unmodifizierten Nanopartiklen gebildeten eine sehr glatte, kompakt erscheinende Oberfläche, was als Hinweis auf eine Kondensation und eine damit verbundene Aggregation der Nanopartikel gewertet wurde. Da sich diese Hypothese anhand der Aufnahmen aber nicht beweisen ließ, wurden in einer nächsten weiterführenden Testreihe Nano-Indenter-Experimente unter dem REM mit den aus voll- und unmodifizierten Nanopartikeln aufgebauten Mikropartikeln durchgeführt. Die Ergebnisse bestätigten den ersten Eindruck der REM-Aufnahmen insofern, als das sich die sehr kompakt wirkenden unmodifizierten Partikel nicht mit einer Wolfram-Spitze eindrücken ließen und damit die Hypothese mechanisch stabiler Aggregate untermauerten. Ganz anders verhielten sich die vollmodifizierten Partikel, die mithilfe der Wolfram-Spitze so eingedrückt werden konnten, dass die Nanopartikel aus dem Mikropartikelverbund herausgelöst wurden und teilweise vereinzelt vorlagen. Hier handelte es sich mit hoher Wahrscheinlichkeit um Agglomerate, die unter der Einwirkung einer Scherkraft wieder vereinzelt werden konnten. Da es mit mikroskopischen Verfahren wie REM nicht möglich war, unmittelbare Aussagen bezüglich der Wechselwirkung der Nanopartikel im Mikropartikel zu treffen, wurden zunächst die Oberflächeneigenschaften mittels BET-, FTIR- und TG-Messungen untersucht. Im Hinblick auf die spätere Anwendung war es sehr wichtig, die Oberflächeneigenschaften der Mikropartikel möglichst umfassend zu charakterisieren, da diese entscheidend zur Dispergierbarkeit der Partikel in einem Matrixsystem beitragen. Mithilfe der FTIR- und TG-Messungen konnte die Anwesenheit und Menge von Silan auf der Partikeloberfläche bestimmt werden. Es zeigte sich ein klarer Trend für die zu verschiedenen Graden mit OCTEO modifizierten Silica-NP. Mit zunehmender Silanmenge nahm sowohl die Intensität der FTIR-Bande für die CH2- und CH3-Streckschwingung als auch der Masseverlust zu. Im Gegensatz zu diesen Messungen zeigte sich bei den BET-Messungen kein klarer Trend in Abhängigkeit vom Bedeckungsgrad der Silica-NP. Die höchsten Werte für die spezifische Oberfläche hatten Mikropartikel, die aus 1/5- und 1/3-modifizierten Silica-NP bestanden. Eine schlüssige Erklärung wird darin gesehen, dass durch die Alkylgruppen auf der Oberfläche ein Kondensieren der Silica-NP weitestgehend verhindert wurde und gleichzeitig noch genügend Mikroporen vorhanden blieben, die mit den Stickstoffmolekülen wechselwirken konnten. Neben den Standard-Analysemethoden wurden Dispergierbarkeitsuntersuchungen durchgeführt sowie die Hansen-Dispergierbarkeitsparameter (HDP) und die ET (30)-Werte mit dem Reichardt-Farbstoff bestimmt. Anhand der Dispergierbarkeitsuntersuchungen konnten erste qualitative Aussagen getroffen werden, ob es sich um hydrophile oder hydrophobe Partikel handelt. Diese ersten Ergebnisse und Trends konnten anschließend mit den HDP und dem RD quantitativ untermauert werden. Die Polarität der Mikropartikel, die aus zu unterschiedlichen Graden mit OCTEO modifizierten Silica-NP aufgebaut waren, nahm mit zunehmender Oberflächenbedeckung ab. Dieser Trend korrelierte mit den aus den FTIR- und TG-Messungen erhaltenen Werten. Da es mit den Silica-basierten Mikropartikeln nicht möglich war, unmittelbare Aussagen zum Agglomerations- bzw. Aggregationsgrad der Nanopartikel im Mikropartikel zu treffen, wurde das Prinzip der Agglomerations/Aggregationssteuerung über Oberflächenmodifikation auf magnetische Nanopartikel übertragen und so ein Modell geschaffen, das die Wechselwirkung auf nanopartikulärer Ebene sichtbar und messbar macht. Diese Informationen zum Agglomerationsgrad der Nanopartikel lieferten wertvolle Hinweise im Hinblick auf die Dispergierbarkeit der Partikel in einer Matrix: Handelte es sich bei den Partikeln um lose Agglomerate, könnten diese zum Beispiel in einem Elastomer wieder auf Primärpartikelgröße dispergiert werden, während Aggregate nur in undefinierte Sekundärstrukturen zerfallen. Gleichzeitig wurde mit dieser Systemübertragung die Frage beantwortet, ob es sich bei den teilmodifizierten Partikeln um eine Mischung aus voll- und unmodifizierten Partikeln handelte oder ob das Silan statistisch über die komplette Oberfläche verteilt war. Wie auch schon beim Silica-System wurden die Nanopartikel zunächst abgestuft mit OCTEO modifiziert (0, 1/10, 1/3, 1/2, 2/3, 1) und anschließend sprühgetrocknet. Aufgrund ihrer magnetischen Eigenschaften konnten die Eisenoxid-Partikel mittels ZFC- und FC-Messungen untersucht werden. Diese spezielle Analysemethode erlaubte es, Aussagen über den Grad der magnetischen Wechselwirkung der Partikel zu treffen und somit indirekt auch über den Grad der Agglomeration/ Aggregation der Nanopartikel im Mikropartikel. Es zeigten sich klare Unterschiede in den Werten für die Blocking-Temperatur (TB) zwischen den voll- und unmodifizierten Partikeln. TB ist die Temperatur, ab welcher die Magnetisierungsrichtung der Partikel aufgrund der thermischen Energie frei fluktuieren kann. Die vollmodifizierten Partikeln hatten einen sehr niedrigen Wert für TB, was auf eine schwache Dipol-Dipol- Wechselwirkung zwischen den einzelnen Eisenoxid-NP schließen ließ, während die unmodifizierten Eisenoxid-Partikel einen hohen TB-Wert hatten, woraus zu schließen war, dass es sich um Aggregate mit einem sehr geringen Partikel-Partikel-Abstand handelte und einer deshalb höheren Wechselwirkung. Die Werte der teilmodifizierten Partikel folgten dem Trend, dass mit zunehmender Silan-Bedeckung der TB-Wert abnahm. Um die Frage der Silan-Verteilung zu beantworten, wurde zusätzlich ein Mischsystem aus voll- und unmodifizierten Eisenoxid-NP versprüht. Sollte es sich bei den teilmodifizierten Partikeln (als Beispiel 1/2) nicht um eine statistische Verteilung der Octylgruppen auf der Oberfläche handeln, müssten die beiden Messungen Übereinstimmungen aufweisen. Dies war allerdings nicht der Fall, was mithilfe der ZFC- und FC-Messungen gezeigt werden konnte. Der TB-Wert des Mischsystems lag zwischen dem der voll- und zu 2/3-modifizierten Partikel, während der Tir-Wert dem der unmodifizierten Partikel entsprach. Die Breite der Aufspaltung zwischen TB undTir konnte als breite Partikelverteilung (Mischung aus Agglomeraten und Aggregaten) interpretiert werden. Im Hinblick auf die Anwendung als Füllstoff wurden die Mikropartikel in eine PDMS-Matrix eingearbeitet und erneut ZFC- und FC-Messungen durchgeführt, wobei die gleichen Trends wie bei den reinen nanostrukturierten Mikropartikeln erhalten wurden. Das bedeutete, dass sich die vollmodifizierten Eisenoxid-NP gut im Elastomer verteilt hatten und somit eine nur sehr geringe Dipol-Dipol-Wechselwirkung vorhanden war. Mit dem entwickelten System der nanostrukturierten Mikropartikel lässt sich der Agglomerations- bzw. Aggregationsgrad der Nanopartikel mehr oder weniger gezielt einstellen, und es können zusätzlich Voraussagen über die Redispergierbarkeit des Partikelpulvers in einer geeigneten Matrix gemacht werden. Basierend auf den gewonnen Erkenntnissen, die zum Verständnis der nanostrukturierten Mikropartikel beitrugen, wurden in einem nächsten Schritt gezielt komplexe Strukturen aufgebaut. Für eine gezielte Strukturierung von Nanopartikeln in Kern-Satellit-Partikel wurde zunächst große 100 nm Silica-NP mit einem PCE funktionalisiert und anschließend mit kleinen und großen unmodifizierten Silica-NP versprüht. Wurden die geeigneten Verhältnisse (70:20:10; 100 nm Mel : 100 nm blank : 20 nm blank) der Partikel zueinander gewählt, konnten Kern-Satellit-Strukturen auf der Mikropartikeloberfläche erzeugt werden. Beim Dispergieren der Mikropartikel in einer Flüssigkeit und in einem Elastomer (PDMS) konnten vereinzelte Kern-Satellit-Strukturen erhalten werden. Um zu bestätigen, dass es sich bei den dispergierten Kern-Satellit-Partikeln nicht um durch Trocknungseffekte entstandene Strukturen handelte, wurden in-situ-Flüssigkeitszellen- TEM-Aufnahmen gemacht. Die Aufnahmen konnten zeigen, dass sich die Kern-Satellit- Partikel in Abhängigkeit zueinander bewegen und nicht jeder Nanopartikel für sich, was auf eine Bindung der Partikel untereinander hindeutete. Neben den Silica-basierten Kern-Satellit-Partikeln konnten auch welche erzeugt werden, deren Satellit-Partikel aus Eisenoxid bestanden. Mit diesem System ist es möglich, multifunktionelle Partikel mit verschiedensten Eigenschaften und Strukturen herzustellen. Teil II: Anwendungspotential nanostrukturierter Mikropartikel Im zweiten Teil der Arbeit wurde zunächst die Anwendung der nanostrukturierten Mikropartikel als Füllstoff in IR und PDMS untersucht. Dafür wurde ein weiteres Silan, Si69TM, zur abgestuften Modifizierung der Silica-NP eingesetzt. Es handelt sich um ein multifunktionelles Silan, welches sowohl an die Partikeloberfläche als auch an das Elastomer binden kann. Bei den mechanischen Untersuchungen der IR-Silica-Komposite zeigte sich, dass das Silan einen entscheidenden Einfluss auf die Verstärkung bei kleinen Deformationen hatte. Während bei dem monofunktionellen Silan (OCTEO) eine direkte Korrelation zwischen Bedeckungsgrad und mechanischer Verstärkung (G') bei gleichbleibendem Füllstoffgehalt beobachtet werden konnte, hatte der Bedeckungsgrad beim multifunktionellen Silan (Si69TM) keinen Einfluss. Anders als bei kleinen Deformationen zeigte sich bei großen Deformationen ein gegenteiliges Bild. Die Verschleißrate der IR-Silica-Komposite nahm bei beiden Silantypen mit zunehmendem Modifizierungsgrad ab, wobei die mit Si69TM modifizierten Partikel-Komposite wesentlich beständiger gegen Verschleiß waren als die mit OCTEO modifizierten Partikel-Komposite, was auf die zusätzliche Matrixanbindung des Si69TM zurückzuführen war. Wurden die IR-Silica- Komposite mit den PDMS-Silica-Kompositen verglichen, konnten keine übereinstimmenden Trends gefunden werden. Im PDMS-System war die mechanische Verstärkung für Mikropartikel aus 2/3 mit OCTEO modifizierten Silica-NP maximal. Diese Unterschiede könnten sowohl auf die unterschiedliche Einarbeitung als auch auf die sehr unterschiedlichen Matrices zurückgeführt werden. Als weitere Anwendung wurden die nanostrukturierten Mikropartikel als Schersensoren für den 3D-Druck untersucht. Hierfür wurden die Silica-NP mit einem PCE modifiziert und anschließend sprühgetrocknet. Um die entstandenen Mikropartikel vollständig in einer Matrix zu dispergieren, waren hohe Scherkräfte und lange Scherzeiten erforderlich, was eine mögliche Anwendung als Schersensor nur schwer realisierbar macht. Teil III: Erweiterung des Ansatzes zur Herstellung nanostrukturierter Mikropartikel auf Hydroxid-basierte Systeme Im dritten Teil dieser Arbeit wurde das System zur Modifizierung von oxidischen Silicaund Eisenoxid-Partikeln auf ein hydroxidisches Systeme übertragen. Hierfür wurden mittels Fällungsprozess LDH-Partikel hergestellt, die anschließend mit OCTEO modifiziert und abschließend sprühgetrocknet wurden. In gleicher Weise wie bei den Mikropartikeln aus Silica-NP nahm der hydrophobe Charakter der LDH-Mikropartikel mit zunehmendem Modifizierungsgrad der Ausgangspartikel zu, was sich anhand von Untersuchungen zur Dispergierbarkeit in Flüssigkeiten unterschiedlicher Polarität zeigte. Zudem ließen sich die aus vollmodifizierten LDHs aufgebauten Mikropartikel in einer PDMS-Matrix wieder in vereinzelte Partikel dispergieren. Die Verstärkung der Komposite war für die teilmodifizierten Partikel (2/3) maximal, da es sich hier, wie auch bei den anderen Partikelsystemen (Silica und Eisenoxid), um eine Mischung aus vereinzelten LDHs und kleineren Aggregate handelte, was aufgrund der starken Füllstoff-Füllstoff-Wechselwirkung zu einer mechanischen Verstärkung bei kleinen Deformationen/Dehnungen führte. Die Eigenschaften der Polymer-Partikel-Komposite ließen sich über den Modifizierungsgrad der Primärpartikel einstellen. Dies konnte für alle drei Partikelsysteme (Silica, Eisenoxid und LDH) beobachtet werden. Ausblick In der vorliegenden Arbeit konnte die Synthese von verschiedenen nanostrukturierten Mikropartikeln und deren einstellbaren Zerfall gezeigt werden. Um den Zerfall der Mikropartikel noch gezielter einstellen zu können, sollte in weiterführenden Arbeiten vor allem die Modifizierung der Nanopartikel noch eingehender untersucht werden. Mithilfe der magnetischen Messungen konnte zwar zwischen einer Mischung aus un- und vollmodifizierten Partikel im Vergleich zu teilmodifizierten Partikel unterschieden werden, es konnten jedoch keine konkreten Aussagen zur Verteilung der Silanmoleküle auf der Partikeloberfläche getroffen werden. Hierfür sollten weitere Charakterisierungsmethoden hinzugezogen werden, die die Modifizierung auf molekularer Ebene analysieren. Zusätzlich sollte die Verteilung/Anordnung der teilmodifizierten Nanopartikel im Mikropartikel untersucht werden. Gerade für Nanopartikel mit einem geringen Modifizierungsgrad (1/10, 1/5 und 1/3) sind verschiedene Anordnungen möglich. Die Nanopartikel können sich während der Sprühtrocknung so anordnen, dass sich die Alkylketten entweder nach außen oder in die Mitte des Mikropartikels orientieren/ausrichten. Die Anordnung der Nanopartikel hat einen großen Einfluss auf die Polarität der entstehenden Mikropartikel- pulver. Darüber hinaus hat sie einen Einfluss auf die Aggregation der Nanopartikel untereinander und somit auf die Bildung von komplexen Unterstrukturen wie zum Beispiel Kern-Satellit-Partikel. Neben der Modifizierung der Nanopartikel sollte die Herstellung der komplexen Strukturen/Suprapartikel weiter optimiert werden. Mit einem detaillierten Verständnis der physikalischen Prozesse während der Sprühtrocknung könnte die Anzahl der Satelliten auf den Kernpartikel kontrollierter eingestellt werden. Grundsätzlich kann das hier entwickelte System der nanostrukturierten Mikropartikel mit einstellbarem Zerfallsverhalten an eine Vielzahl von Anwendungen angepasst werden. Da das System für zahlreiche Partikeltypen (Silica-, Eisenoxid-NP und LDH) geeignet ist, könnten verschiedene Partikel ko-versprüht und so Suprapartikel mit ganz neuen Funktionalitäten und Eigenschaften erzeugt werden. Diese können als verstärkende Füllstoffe in Elastomere oder zur Stabilisierung von Dispersionen eingesetzt werden. Mischpartikel aus Silica- und Eisenoxid-Partikel hätten zum Beispiel den Vorteil, dass sie eine Dispersion stabilisieren und gleichzeitig wieder magnetisch abgetrennt werden können. Diese Mischpartikel könnten auch als Füllstoffe in komplexe Kunststoffbauteile eingearbeitet werden, in denen sie zum einen als mechanisch verstärkender Füllstoff wirken und gleichzeitig durch induktive Erwärmung das Bauteil vernetzt. Beim induktiven Erwärmen handelt es sich um eine schonende Methode Bauteile gezielt zu vernetzen, indem die Wärme im Bauteil selbst, über magnetische Verluste der Magnetpartikel in einem magnetischen Wechselfeld, erzeugt wird und nicht über seine Oberfläche eingebracht werden muss. Eine weitere interessante Anwendung für Mischpartikel ist die als magnetooptisch aktiver Marker oder Tracer in der medizinischen Diagnostik. Aufgrund von Quenching-Effekten (Auslöschungseffekte) ist es schwierig magnetische Nanopartikel mit einer Farbigkeit oder Fluoreszenz auszustatten.[385] Mischt man jedoch die magnetischen Nanopartikel mit einem weiteren Partikelsystem wie zum Beispiel Silica-NP oder LDHs, können magnetooptische Eigenschaften erhalten werden ; The herein presented work deals with the synthesis and characterization of nanostructured microparticle powders with adjustable burst behavior and their application as reinforcing fillers as well as their application as a shear sensors. For this purpose, the work was structured into three parts. The first part was dedicated to the synthesis of nanostructured microparticle powders produced by spray-drying colloidal nanoparticles. Depending on the composition of the particles during the spray-drying process, it was possible to produce nanoparticulate structures such as core-satellites. In the second part of the work, these nanostructured microparticles could be redispersed in a suitable matrix such as polydimethylsiloxane (PDMS) and then tested for a potential application as reinforcing fillers. In the third and final part of the work, the synthesis approach was extended to hydroxide-based systems such as layered double hydroxides particles (LDHs). Part I: From silica nanoparticles to nanostructured microparticles with adjustable burst behavior To generate nanostructured microparticles with an integrated burst behavior, colloidal silica nanoparticles with a size of 20 nm were either partially or completely (1/10, 1/5, 1/3, 1/2, 2/3, 1) modified with triethoxyoctylsilane (OCTEO), which makes the nanoparticle surfaces hydrophobic or semi-hydrophobic, or the nanoparticles were left blank (0). To achieve the part-modification" the amount of silane was reduced accordingly to 2/3, 1/2, 1/3, 1/5 and 1/10 compared to the completely modified silica nanoparticles. The modified nanoparticles showed clear differences when dispersed in different liquids (water, toluene) depending on the silanization degree of the particle surface. As expected, the hydrophobic behavior of the nanoparticles increased with increasing silane coverage and the nanoparticles were redispersible in non-polar liquids such as toluene while they tended to agglomerate and sediment in polar liquids such as water. In a next step, the colloidal silica nanoparticles, which were modified to different degrees with OCTEO, were spray-dried to yield a powder. The obtained nanostructured microparticle powders were then characterized by various analysis methods such as scanning electron microscope (SEM), specific surface area measurement by nitrogen adsorption according the Brunauer, Emmett and Teller theory (BET), FTIR measurements and thermogravimetric analysis (TGA) to examine the properties of the formed particles in more detail. SEM revealed that the nanostructured microparticles showed a very different appearance depending on the degree of modification of the nanoparticles. The microparticles consisting of completely modified nanoparticles had a rather rough surface, while the ones consisting of non-modified nanoparticles had a very smooth and compact surface, which could be due to possible condensation and associated hard agglomeration of the nanoparticles. Since based on SEM images alone it was not possible to confirm this assumption, in a next series of tests, in situ nano-indenter experiments were carried out in the SEM with microparticles composed of completely and non-modified nanoparticles. These results finally confirmed the first impression gained by SEM, as the very compact non-modified particles could not be indented with a tungsten tip which is possibly a good indication that hard agglomerates prevail in this case. The completely modified particles could be indented with the tungsten tip, thus behaved quite differently. The microparticles showed a ductile/plastic behavior and the nanoparticles could be separated from each other. This suggests that these particles probably consist of soft agglomerates of nanoparticles which can be separated again by force. Since it was not possible to make substantiated statements regarding the interaction of the nanoparticles within the microparticle with microscopy methods such as SEM, the surface properties of the particles were studied using BET, FTIR measurements and TGA. With a view to later applications, it it was important to characterize the surface properties of the microparticles in detail, since these are essential for the dispersibility of the particles in a matrix system. Using FTIR measurements and TGA the presence and amount of silane on the particle surface was determined. There was a clear trend for the silica nanoparticles which were modified to different degrees with OCTEO. As the amount of silane increased, both the intensity of the FTIR band for CH2 and CH3 stretching and mass loss increased. In contrast to these measurements, the BET measurements showed no clear trend depending on the surface coverage of the silica nanoparticles. The highest values for the specific surface area were found for microparticles consisting of 1/5- and 1/3-modified silica nanoparticles. In these cases, the condensation of the silica nanoparticles was largely prevented by the surface alkyl groups, and at the same time, there were still enough micropores that were able to interact with the nitrogen molecules which may explain the higher values. In addition to the standard analytical methods, liquid tests were performed and Hansen dispersibility parameters (HDP) and ET (30) values with Reichardt's dye (RD) were determined. Based on the liquid tests, first qualitative statements, concerning the hydro- philicity or hydrophobicity of the particles, modified to a different extend with silane, were made. These results and trends were then quantitatively substantiated with the HDP and the RD experiments. The polarity of the microparticles which were built up to different degrees with OCTEO modified silica nanoparticles decreased with increasing surface coverage. This tendency correlated with the values obtained from the FTIR and TG measurements. Since it had not been possible so far to determine the degree of soft and hard agglomeration of the silica nanoparticles in the microparticles, the system was transferred to iron oxide nanoparticles. The degree of agglomeration of the nanoparticles was crucial for subsequent dispersion in a matrix: If the particles were loose, soft agglomerates, they could be redispersed into primary nanoparticles in an elastomer, while hard agglomerates would only disintegrate into undefined secondary structures. At the same time, this system transfer was intended to answer the question whether the partially modified particles are a mixture of completely and non-modified particles or whether the silane is statistically distributed over the entire surface of all nanoparticles, i.e. whether all nanoparticles are modified to the same extend with silane. Similar to the silica system, the iron oxid nanoparticles were modified to different degrees with OCTEO (0, 1/10, 1/3, 1/2, 2/3, 1) and then spray-dried. Due to their magnetic properties, the iron oxide particles could be analyzed by Zero-Field-Cooled (ZFC) and Field-Cooled (FC) measurements. This special analysis method made it possible to deduce statements on the degree of the magnetic interaction of the particles and thus indirectly on the degree of soft and hard agglomeration of the nanoparticles in the microparticle. There were significant differences in the blocking temperature (TB) between the completely and the non-modified particles. TB is the temperature at which the magnetization direction of the particles can freely fluctuate due to thermal energy. The completely modified particles had very low TB value, suggesting a weak dipole-dipole interaction between the individual iron oxide nanoparticles. In contrary to this, the non-modified iron oxide particles had a high TB value, suggesting that the nanoparticles form hard agglomerates , coming with a very small particle-particle distance and therefore a higher interaction. The values of the partially modified particles followed the trend that the TB value decreased with increasing silane coverage. In order to answer the question of the silane distribution, a mixed system consisting of completely and non-modified iron oxide nanoparticles was also spray-dried. If the partially modified particles (as example 1/2) were a mixture of non-modified and modified nanoparticles and therefore the silane was not statically distributed on the nanoparticle surface, the TB value should be the same as for the mixed system. This was not the case however, as demonstrated by the ZFC and FC measurements. The TB value of the mixed system was between the one of the completely and 2/3-modified particles, while the irreversible temperature (Tir) value corresponded to that of the non-modified particles. The width of the splitting between TB and Tir could be interpreted as a broad particle distribution (mixture of soft and hard agglomerates). For the use as fillers, the microparticles were incorporated in a PDMS matrix and ZFC and FC measurements were again performed, and the same trends were observed as for the pure nanostructured microparticles. From this it could be concluded that the completely modified iron oxide nanoparticles had been well distributed in the elastomer and thus had very little dipole-dipole interaction. With the developed system of nanostructured microparticles, the degree of soft and hard agglomeration of the nanoparticles can be adjusted more or less specifically, and additional predictions can be made about the redispersibility of the particle powder in a suitable matrix. Based on the insights gained to understand the system, more complex structures were built up. For the adjustable structuring of nanoparticles in core-satellite particles, large 100 nm silica nanoparticles were firstly functionalized with a polycarboxylate ether (PCE) and afterwards spray-dried with small and large non-modified silica nanoparticles. By choosing a suitable ratio (70:20:10, 100 nm Mel : 100 nm blank : 20 nm blank) of the particles composition was chosen, core-satellite structures were generated on the microparticle surface. The dispersion of microparticles in a liquid or in an elastomer (PDMS) resulted in isolated core-satellite structures. In situ liquid cell TEM was carried out to confirm that the dispersed core-satellite particles were not only structures created by drying-effects. It was possible to record core-satellite particles moving/rotating in relation to each other which was an indication that the small particles were bound to the larger ones. In addition to the silica-based core-satellite particles, core-satellite particles were synthesized whose satellite particles consisted of iron oxide. This proved the approach being suitable to produce multifunctional particles with different properties and structures. Part II: Application potential of nanostructured microparticles In the second part of the work, the application of the nanostructured microparticles as reinforcing fillers in isopren rubber (IR) and PDMS, as well as shear sensor in 3D printing was examined. For this purpose, the silica nanoparticles were modified with the silane bis(triethoxysilylpropyl)tetrasulfide (Si69TM) in addition to OCTEO. Si69TM is a multifunctional silane capable of covalently binding to both, the particle surface via the ethoxy groups and the elastomer via the sulphur. The mechanical investigations of the IR-silica composites demonstrated that the silane modification of the silica nanoparticles had a significant influence on the reinforcement at small strain amplitudes. While the monofunctional silane (OCTEO) revelaed a direct correlation between the degree of coverage and mechanical reinforcement (G') at a constant filler content, the degree of coverage of the multifunctional silane (Si69TM) had no effect. In contrast to small strain amplitudes, a completely different behavior was found for large strain amplitudes. The wear rate of the IR-silica composites decreased with increasing modification degree for both silane types. The Si69TM modified particle composites were much more resistant to wear than the OCTEO modified particle composites due to the additional matrix binding of the Si69TM. When comparing the IR-silica composites to the PDMS-silica composites, no consistent trends were found. In the PDMS system, the mechanical reinforcement by the particles was at maximum for particles being modified on their surface to an extend of 2/3 by OCTEO. These differences could be attributed to the different incorporation processes as well as the different matrices. Another potential application for the nanostructured microparticles as shear sensor in 3D printing was tested. For this purpose, the silica nanoparticles were modified with a PCE and then spray-dried. In order to completely disperse the resulting microparticles in a matrix, high shear forces and long shear rates were required, which makes a potential application as shear sensor for the current system rather challenging to be realized in practice. Part III: Extension of the approach for the preparation of nanostructured microparticles to hydroxide-based systems In the third part of this work, the system of silica particle modification was transferred to hydroxide-based particles. For this purpose, LDHs were produced by a precipitation process and then modified with OCTEO and finally spray-dried. LDHs are an interesting material due to the broad application potential like as adsorbers for gases, drug containers, and flame-retardants. Exactly as with the silica particles, the hydrophobic character of the LDH microparticles increased with increasing modification degree of the primary LDHs which could be shown by liquid tests. In addition, the microparticles consisting of completely modified LDHs could be dispersed into isolated particles in a PDMS matrix. Similar to the silica particle systems, the reinforcement of the composites was the highest for the partially modified particles (2/3). The partly modified particles consisted of a mixture of isolated LDH particles and small hard agglomerates, which lead to a mechanical reinforcement at small strain amplitudes due to the strong filler-filler interaction. The properties of the polymer-particle composites could be adjusted by the modification degree of the primary LDHs. Outlook In the present work, the synthesis of different nanostructured microparticles and their adjustable burst was shown. In order to be able to carefully adjust the disintegration of the microparticles, the modification of the nanoparticles in particular should be investigated in more detail in future woks. Although it was possible to differentiate between a mixtures of non-modified and completely modified particles compared to partially modified particles, it was not possible to make any specific statements about the distribution of the silane molecules on the particle surface. For this purpose, further characterization methods should be consulted, which analyze the modification at the molecular level. In addition, the distribution/arrangement of the partially modified nanoparticles in the microparticle should be investigated. Especially for nanoparticles with a low degree of modification (1/10, 1/5 and 1/3) different arrangements are possible. During spraydrying, the nanoparticles can either be arranged in such a way that the silane molecules orient themselves in the direction of the particle surface or in the center of the particle. The arrangement of the nanoparticles has a great influence on the polarity of the resulting microparticle powders. In addition, it has an influence on the hard agglomeration of nanoparticles and thus on the formation of complex substructures, such as core-satellite particles. In addition to the modification of the nanoparticles, the production of complex structures/supraparticles should be further optimized. With a detailed understanding of the physical processes during spray-drying, the number of satellites on the core particles could be more controlled. In principle, the system of nanostructured microparticles with adjustable burst behavior, which has been developed herein, can be adapted to a large number of applications. Since the system is suitable for many types of particles (silica, iron oxide and LDH), different nanoparticle building blocks particles could be spray-dried together to create supraparticles with completely new functionalities and properties. These can be used as reinforcing fillers in elastomers or for the stabilization of dispersions. For example, mixed particles of silica and iron oxide particles would have the advantage to stabilize a dispersion and at the same time may be magnetically recovered again. These mixed particles could also be incorporated as fillers into complex plastic components in which they act as mechanically reinforcing fillers on the one hand and, at the same time, crosslink the components by inductive heating. The inductive heating is a gentle method to selectively crosslink components, since the heat produced by the magnetic particles in the component itself and does not have to be introduced over its surface
La première partie de cette thèse de doctorat est composée de 6 chapitres. Celle-ci décrit une méthodologie originale afin d'estimer les performances économiques, énergétiques et environnementales des installations d'un réseau de chaleur. Le chapitre 1 résume les différents contextes dans lesquels s'inscrit le travail de recherche. Le contexte énergétique mondial de la consommation d'énergie primaire liée au chauffage et à la climatisation des bâtiments est tout d'abord détaillé. En effet, ce travail se concentre sur l'alimentation de bâtiments par le biais des réseaux de chaleur qui sont, à leur tour, détaillés. Pour alimenter ceux-ci, l'usage de la biomasse et des unités de cogénération sont également abordés au sein de ce premier chapitre. Le chapitre 2 détaille le cas d'étude qui est utilisé pour éprouver la méthodologie développée dans le travail de recherche. À l'aide de ses spécificités et des notions introduites dans le chapitre 1, des objectifs généraux sont définis. Le chapitre 3 délimite les objectifs du présent travail de recherche sur base de ceux établis dans le chapitre 2. Pour y parvenir, les différentes méthodes utilisées sont à leur tour détaillées et référencées au travers des articles scientifiques constituant la partie 2 de ce manuscrit. Finalement, les outils informatiques utilisés pour réaliser ces objectifs sont également abordés. Le chapitre 4 détaille les résultats des articles scientifiques 3, 4 et 8 de la partie 2 de ce manuscrit concernant la modélisation du transport de l'énergie thermique. L'article 3, sur base des limitations observées pour une méthode de modélisation couramment utilisée (volumes finis) pour la simulation du transport de l'énergie thermique, détaille uneméthode alternative de simulation du transport de l'énergie thermique dans le langage du logiciel Matlab. Cette méthode considère non seulement les pertes à l'ambiance de la canalisation, mais également l'inertie thermique de celle-ci dont l'influence sur le transport d'énergie est démontrée. L'article 4 valide cette approche expérimentalement sur une installation de laboratoire et sur une portion d'une canalisation du réseau de chaleur du cas d'étude. L'article 8 établit un état de l'art des différentes méthodes de modélisation du transport d'énergie thermique qui conclut sur la nécessité d'utiliser une méthode alternative pour l'estimation dynamique des pertes à l'ambiance et du transport de l'énergie thermique d'une canalisation. Cet article propose d'utiliser la méthode envisagée de l'article 3 en l'adaptant au langageModelica. Par ailleurs, cette méthode alternative est à son tour validée sur l'installation de laboratoire utilisée dans la validation expérimentale de l'article 4 ainsi que sur une portion d'un réseau de chaleur existant constituée de plusieurs consommateurs. Le chapitre 5 présente les résultats obtenus pour l'analyse d'un réseau de chaleur qui sont résumés dans les articles scientifiques numérotés 1, 2, 5, 6, 7 et 9 de la partie 2 de ce manuscrit et des compléments sont également abordés le cas échéant. L'article 1 présente une modélisation détaillée de la combustion de la biomasse et du gaz naturel afin d'estimer les émissions de plusieurs polluants tout en s'attardant sur la formation des oxydes d'azote et de soufre. L'article 2 présente une méthodologie permettant d'estimer le coût de la chaleur et le bilan des émissions de dioxyde de carbone d'un réseau de chaleur et compare ce système de chauffage à d'autres alternatives. Pour arriver à cet objectif, plusieurs modèles sont détaillés et validés expérimentalement afin d'estimer les performances des différentes installations constituant un réseau de chaleur (chaudière, unité de cogénération, réseau de chaleur). Finalement, plusieurs scénarios visant à améliorer le réseau de chaleur et l'unité de cogénération sont envisagés et comparés à l'aide de la méthodologie développée. L'article 6 et l'article 7 envisagent, quant à eux, des scénarios alternatifs permettant de diminuer le coût de la chaleur du réseau de chaleur sur base des modèles développés dans l'article 2. L'article 6 envisage l'ajout d'un stockage d'énergie thermique afin de maximiser l'usage d'une unité de cogénération alimentant le réseau de chaleur pour diminuer les coûts et l'impact environnemental du réseau de chaleur. Le stockage d'énergie est considéré sous deux formes: un ballon tampon d'eau chaude placé à proximité du réseau ainsi qu'une régulation adaptée permettant d'utiliser l'inertie thermique propre du réseau de chaleur. De plus, un stockage d'énergie à court terme et saisonnier sont envisagés afin de vérifier leur pertinence avec le contexte du réseau de chaleur étudié. Sur base des résultats obtenus, la politique des subsides liée à l'utilisation de l'unité de cogénération est analysée afin de pointer son adéquation avec le contexte du réseau de chaleur étudié. L'article 7, quant à lui, envisage l'ajout d'une pompe à chaleur haute température à un endroit stratégique du réseau de chaleur qui nécessite une haute température d'alimentation en eau chaude pour générer de la vapeur. Ce scénario est basé sur l'hypothèse qu'en réduisant la températuremoyenne du réseau grâce à cette pompe à chaleur, il serait possible de limiter les pertes à l'ambiance de celui-ci et donc de potentiellement réduire les coûts associés et l'empreinte environnementale. L'article 5 complète l'analyse des réseaux de chaleur en détaillant une méthodologie afin d'estimer les performances énergétiques, exergétiques et environnementales de différents systèmes de chauffage, dont les réseaux de chaleur, afin de comparer ces solutions dans leur globalité. Le chapitre 6 résume les conclusions du travail de recherche et propose des perspectives à celui-ci. La seconde partie de cette thèse de doctorat est composée des 9 articles scientifiques qui ont été préalablement abordés et d'une section consacrée à corriger une erreur présente dans l'un des articles scientifiques et à préciser un aspect lié à l'unité de cogénération étudiée, à savoir l'évolution de sa puissance nominale au cours des études. ; The first part of this doctoral thesis is composed of 6 chapters. Chapter 1 summarizes the different contexts in which the research work takes place. The global energy context for primary energy consumption related to heating and cooling buildings is firstly detailed. Indeed, this work focuses on the supply of buildings through district heating networks which are then detailed. To feed these district heating networks, the use of biomass and cogeneration units are also discussed in this first chapter. Chapter 2 presents the case study used to test the methodology developed in the research work. Using its specifications and the concepts introduced in chapter 1, general objectives are defined. Chapter 3 delineates the objectives of this research work on the basis of those set out in chapter 2. To achieve this, the different methods used are detailed and referenced through the scientific articles constituting the part 2 of this manuscript. Finally, the computer tools used to achieve these objectives are also briefly discussed. Chapter 4 presents the results of scientific articles 3, 4 and 8 of the part 2 of this manuscript concerning thermal energy transport modeling. Article 3, based on the limitations observed for a modeling method (finite volumes) commonly used for thermal energy transport modeling, details an alternative method of thermal energy transport simulation in the Matlab software language. This method considers not only the heat losses to the pipe environment but also the thermal inertia of the pipe whose influence on energy transport is demonstrated. Article 4 validates this approach experimentally in a laboratory test bench and on a portion of a heating network pipe of the case study. Article 8 establishes a state of the art of the different thermal energy transport modelling methods which concludes on the requirement to use an alternative method for the dynamic estimation of heat losses and thermal energy transport of a pipeline. This article proposes to use the method envisaged in article 3 by adapting it to the Modelica language. Furthermore, this alternative method is validated on the laboratory installation used in the experimental validation of article 4 as well as a portion of an existing heating network consisting of several consumers. Chapter 5 presents the results obtained for the analysis of a heating network, which are summarized in the scientific articles numbered 1, 2, 5, 6, 7 and 9 in part 2 of this manuscript, and supplements are also discussed where required. Article 1 presents a detailed modeling of biomass and natural gas combustion in order to estimate the emissions of several pollutants while focusing on the formation of nitrogen oxides. Article 2 presents a methodology to estimate the cost of heat and the carbon dioxide emissions balance of a heating network and compares this heating system with other alternative technologies. To achieve this objective, several models are detailed and validated experimentally in order to estimate the performances of the various installations constituting a heating network (boilers, cogeneration unit, heating network). Finally, several scenarios to improve the heating network and the cogeneration unit are considered and compared using the methodology developed. Article 6 and Article 7 consider alternative scenarios for reducing the cost of heating the heating network on the basis of the models developed in Article 2. Article 6 investigates the addition of thermal energy storage in order to maximize the use of a cogeneration unit feeding the heating network. Energy storage is considered in two forms: a hot water buffer storage tank placed close to the network and an adapted regulation allowing the use of the thermal inertia of the heating network. In addition, short-term and seasonal energy storage are considered to verify their relevance to the context of the heating network under study. On the basis of the results obtained, the subsidy policy linked to the use of the cogeneration unit is analyzed in order to determine its adequacy in the context of the case study. Article 7, for its part, envisages the addition of a high-temperature heat pump at a strategic point in the heating network that requires a hot water supply temperature to generate steam. This scenario is based on the assumption that by reducing the average temperature of the network thanks to this heat pump, it would be possible to limit the losses to the environment of the network and thus potentially to reduce the associated costs and the environmental footprint. Article 5 complements the analysis of heating networks by detailing a methodology to estimate the energy consumption and the energetic and environmental performances of different heating systems, including heating networks, in order to compare these solutions as a whole. Chapter 6 summarizes the findings of the research and offers perspectives for research. The second part of this doctoral thesis is composed of the scientific articles that were previously discussed and a section devoted to correct an error present in one of the scientific articles and to specify an aspect related to the cogeneration unit studied, namely the evolution of its rated power during the studies.
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Industrial agriculture delivers cheap food at high cost in terms of degraded land, water resources, biodiversity and rural societies. It exacerbates floods and droughts, and creates enormous greenhouse gas emissions. There is an alternative: regenerative agriculture that mimics natural ecosystems, holding to four rules: no bare soil, no tillage, a diverse crop rotation and a rough landscape that includes woods and wetlands. Subsidising regenerative farming is politically feasible whereas, probably, taxing land degradation is not. Farmers may be encouraged to adopt regenerative farming through small changes to the EU's Common Agricultural Policy (CAP) whereby farmers could form Landcare Groups which would develop a regenerative farming brand – analogous to a protected name such as Chianti Classico. They could then sell their brand to a regional Sustainable Farming Panel and, if authenticated, it could receive a subsidy under the CAP.The cost of food Food prices and food security are existential issues for governments as well as consumers. Since the early 19th century, governments have had to grapple with the competing claims of farmers, manufacturing and popular interests. In the UK, the repeal of the Corn Laws in 1846 was a victory for popular interests. Since then, most governments, most of the time, have left the food system to the market and food prices have been driven down – notwithstanding wartime spikes and oil-price shocks. Society has been comfortingly deluded that the food system works. It delivers cheap food to consumers but stresses farmers and degrades the land. Governments nurture the delusion, hide the harm by buying off the farmers and ignore the erosion of natural capital. But the system doesn't deliver cheap food: it delivers underpriced food. The real price is being paid by underpaid labour, the taxpayer and degradation of soil, water, biodiversity and climate stability. None of these is accounted for in the price of food. Governments subsidise farmers to support livelihoods, maintain rural economies, guarantee a degree of food self-sufficiency and protect landscapes and ecosystem services. This last intent is reinforced by compliance conditions, but the bar has never been set very high; this is an area of policy making where the state is learning on the hoof (Allan and Dent, 2021: 3-20). The subsidy model has two tracks. Payment by results was an early policy of the European Union (EU) Common Agricultural Policy (CAP). Farmers responded to the incentive and the outcomes included the butter mountain and the wine lake; cheap credit for big machinery and grants for ripping out hedgerows created more environmental damage. Nowadays, subsidies are shifting to activities: areas reserved for birds and bees receive a subsidy whether or not they are endorsed by the birds and the bees – the activity, not the result, entitles the farmer to financial support. Our proposal to support regenerative farming – exemplified here by the Chianti Classico model – is also based on activities because the results are too complex to assess and don't provide a tangible target for farmers. The need to relearn the last 70 years For decades after the end of the Second World War, farming was flooded with cheap fertilisers and miraculous agrochemicals. Fossil fuels were cheap; the military-industrial complex sidestepped adroitly from explosives to fertilisers, from poisons to pesticides; plant breeders developed responsive new varieties. Together, these gifts of technology created the much-trumpeted "Green Revolution" that, in favourable situations, tripled the yields of staple crops. Favourable situations are unequally distributed so, simultaneously, we saw globalisation of the food system and relocation within individual countries. One of the authors of this essay, Brian Chatterton, lives on an abandoned farm in Umbria (Italy) where sharecroppers, the contadini, deserted a life of labour and poverty for paid work in the prosperous north; and livestock were abandoned because there were no herdsmen. A century earlier, in one of the aurhors' country of origin, in Australia, when farm labour joined the gold rush, farmers introduced fences to control their livestock. Fences were not introduced in Italy; instead, the livestock moved to feedlots – not just a move away from grazing but, also, to make use of the great global grain surplus. In the process, manure was converted from a fertiliser to a pollutant. The gifts of technology came with other calamitous consequences – climatic, ecological and social – and the industrial inputs are now expensive and likely to remain so. As a result, an unsustainable situation has been created. There is an alternative to this nonviable process. Over the last 70 years, regenerative agriculture has emerged as a farmers' movement, without fanfare, and has been adopted across 15% of the world's cropland, in particular in North America and Europe.What is regenerative agriculture? Regenerative agriculture is the antithesis of the "Green Revolution". It emerged under the banner of "Conservation Agriculture" (Kassam, 2020), but the aim is not preservation of what remains of soil, water and biodiversity but building back better by mimicking natural ecosystems. Here are its four rules: First Rule: "Ban Bare Soil". Bare soil invites invasion by weeds. Every year, they must be rooted out, the soil turned and we start again – with bare soil. Bare soil bakes in the sun; so do earthworms and myriad smaller creatures that should be maintaining soil permeability. Rain splash turns bare soil into mud – mud that clogs the pores so that rainwater ponds or runs off the surface, carrying the soil with it. When the rain stops, the pulverised surface sets as a crust that yields immediate runoff from the next rainstorm. And bare soil is carried off by the wind: three-quarters of the topsoil and three and a half million people left the Dust Bowl of the American Plains states in the 1930s. The rule is: don't fallow and, between crops, keep the soil covered with a mulch of crop residues. This keeps it cool, arrests soil erosion, and allows all the rain and snowmelt to infiltrate. Second Rule: "Don't Plough".The purpose of ploughing is to control weeds. Weeds can be controlled by crop rotation without resort to poisonous chemicals. Ploughing uses 60-70% of the energy (labour and diesel fuel) consumed in agriculture – and stimulates germination of more weeds. Worse still, it perturbs the soil's physical and biological structure and promotes the breakdown of soil organic matter – the fuel of life in the soil, the glue that binds soil structure, and which holds more carbon than the atmosphere and all standing vegetation put together. Centuries under the plough have drastically depleted soil organic matter. Stop ploughing, and a net loss of soil organic carbon is transformed to a net gain that draws down the carbon dioxide concentration in the atmosphere; and direct drilling leaves the soil surface protected by crop residues. Third Rule: "Adopt a diverse crop rotation".Natural vegetation is diverse and mostly perennial. Recent advances in crop breeding have brought the yields of perennial cereals and oilseeds within touching distance of established annual varieties (Crews, et al., 2018) but, until they are truly commercial, the next best thing is to follow a diverse crop rotation that includes perennial grasses and legumes – both as crops and pastures. Under this rotation, yields of cash crops are greater than any alternative monoculture; integration of crops and livestock makes good use of the additional biomass; and the costs of fertiliser, herbicides and pesticides are cut if not completely eliminated. Fourth rule: "Create a rough landscape".Restore wetlands and woodlands. Plant windbreaks. Windbreaks are shirts for fields; allocation of 4% of the land area to windbreaks brings a benefit-cost dividend of 10% through lower air temperature, greater humidity, cutting wind speed, retaining snow and runoff, arresting erosion and increasing biodiversity. Moreover, the increased surface roughness creates convectional rainfall; and the transpiration of trees and other perennial vegetation, drawing on deep water reserves, promotes the local water cycle and a more habitable landscape. Regenerative farming is commercial: It is a good livelihood, not the fantasy of a wealthy philanthropist. Regenerative farming is profitable but not obsessed with crop yields because greatly reduced costs and risk contribute to profits as well. Rather, it is possessed by sustainability: meeting the needs of the present without compromising the future. For instance, for several generations, the Chatterton farm in South Australia grew two wheat crops in succession after two or three years of poor pasture grounded on ephemeral grasses. Changing the poor pasture to a protein-rich sward of annual medick immediately improved soil fertility – though not wheat yields because weeds benefitted as well. Costs were much lower, because nitrogen fertiliser was eliminated, and sheep numbers increased from 500 to 1,200 (and the sheep were better fed). The whole system was more productive, more profitable. Regenerative farming can also be intensive as the Chinese, Koreans and Japanese demonstrated for millennia (King, 2004); intensive production requires intensive regeneration and that is what they did. Regenerative agriculture is not anti-science: It doesn't reject all the progress made in the last 70 years. It doesn't reject disease-resistant crops and thousands of other scientific advances. It does reject the view we learned at university, half a century ago, that the soil is merely a neutral growth medium and everything else the plant needs can be supplied by the chemical industry. Regenerative agriculture is not nostalgic:We are not advocating ox-drawn ploughs or the return of poor sharecroppers. Some farmers will adopt old crop varieties provided that there is a market for them, but the concept is not to turn our back on scientific advances. If they really are advances, adopt them. Brian Chatterton, for instance, inherited a farming system that burnt any remaining stubble before drilling the next cereal crop and, so, further reducing what was already a low soil organic matter content. We have no wish to return to this destructive practice. Is regenerative farming the same as organic farming? No. They are not the same although they are moving in the same direction. They cater for different markets. Organic farming eschews industrial chemicals like artificial fertilisers, pesticides and weedkillers so as to satisfy the concerns of the affluent who are anxious about chemical residues in their food and are prepared to pay a premium to avoid them. From the farmers' point of view, organic farming requires a great deal more capital, both monetary and human, and the market premium depends on organically grown food being a niche product. Both organic farming and regenerative farming replace chemicals with knowledge, but organic farmers have to make this investment for several years before they attain organic status and qualify for the price premium. Those years without the price premium, nominally to rid the system of industrial residues, are also needed to master the alternative organic farming practices – for instance, controlling pests without industrial pesticides. In the EU, wider uptake of regenerative agriculture will depend on subsidy from the CAP, which we would call payment for environmental services – services that include arresting soil erosion, delivery of fresh water, moderation of floods and droughts, and cutting emissions of greenhouse gases. We assume that the market will not reward farmers who provide these services, so a CAP subsidy will be invaluable during the years of adoption and adaptation to acquire the necessary skills and the equipment. Why should regenerative farming be adopted? To arrest soil erosion: Archaeological evidence shows, for instance, that soil erosion in central Italy during the last 70 years has been greater than the previous 2,000 years of recorded farming history. The erosion map of Europe (Panagos et al., 2020) confirms that Italy has more soil erosion than any other European country. It has hills and mountains but so do other European countries; and if erosion continues at this rate, we can no longer count the future of fields in decades. But soil erosion is arrested by a complete vegetation cover, as practised by regenerative agriculture. Stopping soil erosion is the main reason given by farmers, worldwide, for adopting regenerative farming: they want to stay in business and pass on a productive farm to their children. Direct cost of current system: The war in Ukraine has pushed up fuel prices and, in turn, the price of fertilisers. For farmers, these costs been offset to some degree by an increase in farm gate prices – which have fed through to higher costs for animal feed – but farm gate prices have fallen away again. Prices depend very much on what the international commodity traders decide is in their best interests: the farmers will have no say. Farmers must pay on the nail for their inputs, but their outputs are at risk from world prices and the weather. No-till farming obviously makes a big saving, not just in fuel, fertiliser and pesticides but in wear and tear and tractor power requirements. Carbon footprint of fertilisers and their further pollution:Manufacture of nitrogenous fertiliser requires a lot of energy and its nitrogen-use efficiency is commonly less than 33%. These fertilisers are readily leached, contaminating streams, groundwater and drinking water; and their breakdown in the soil releases nitrogen oxides – with 300 times the greenhouse effect of the equivalent amount of carbon dioxide. As temperatures rise and droughts intensify, emissions will increase. To regulate water supply, control floods and droughts:Continuing with the case of Italy, this country faces several water crises but they all stem from the state of the soil. The first requirement is to catch the rain and snowmelt. Under nearly all circumstances, a well-protected, well-structured soil will infiltrate all the precipitation it receives. If there is no runoff, there is no flooding and no sedimentation of streams and reservoirs; the soil stays in place, where we all need it to be. Vegetation or, failing that, a mulch of crop residues protects the soil surface from sun, wind and rain; and enhances soil structure – that is to say, the architecture of the pore space that holds and transmits water. To increase soil organic matter: Soil structure is held together by soil organic matter; the more organic matter, the more resilient the structure. Soil organic matter is also the primary source of plant nutrients, which are steadily released by microbial decomposition under the very same conditions that growing plants need – not in a rush as with artificial fertilisers, so losses by leaching are minimal. Soil organic matter increases under regenerative agriculture because there is more biomass and less decomposition under more equable soil temperatures, the absence of intensive soil disturbance, and without periodic erosion of the topsoil. Cultivate less: Cultivation accelerates the breakdown of soil organic matter which releases the nutrients it holds, so the ploughing of virgin soils provided bumper yields. But yields crashed when the humus was not replaced. Under the current conventional farming system in large parts of Europe, the land is ploughed deeply using powerful tractors that burn a lot of fuel. Ploughing buries the weeds and stubble left from the previous crop but, at the same time, destroys soil structure and permeability and creates a pan at the plough sole that needs even deeper cultivation to break it up. Having used a lot of energy to upend the soil, the farmers have created fields of hard clay bricks that require yet more power to smash them down into a reasonable seed bed. Farmers need to acquire different machinery and use it differently. As a first step, they shouldn't turn everything upside down. Leaving crop residues on the surface protects the soil from the elements and supplements soil organic matter; but increasing soil organic matter also means retaining all crop residues rather than selling bales of straw to livestock farmers. As soil organic matter increases, soil structure improves; the clods will crumble and require less force to create a seedbed. It follows that tractors do not need to be so big and heavy; sowing can be undertaken at the optimum time; autumn rains will be more effective; and undisturbed soil enables mycorrhizal fungi – old friends of higher plants – to proliferate their slow-growing hyphae throughout the soil profile, absorbing and passing on otherwise hard to get nutrients like phosphate. Grow legumes: Sustainable farming also needs legumes that fix their own nitrogen fertiliser from the air and, in turn, release the nutrients for intercrops or other crops in rotation. Bring back grazing: There is little interest in improved pastures in mainland Italy, although there are such legume pastures in Sardinia. A similar situation prevails in much of Europe. Perennial lucerne, erba medica in Italy, is very productive but hard to incorporate into a cereal rotation. The advantage of legumes in grazed pastures or leys is that more of the nitrogen fixed by the plants is retained and the biomass, returned as manure, is spread for free. Animals on feedlots are fed on imported soya and grains grown using chemical fertiliser, and their manure is not conveniently recycled.Retain stubble: A decline in feedlots will also cut the market for straw. Leaving the straw in the field will increase soil organic matter but cereal straw is poor in nitrogen. Microorganisms breaking down the straw take up nitrogen from the soil, in competition with growing crops, so it can pay to add some pump-priming nitrogen fertiliser or a commercial stubble bio-decomposer. Once the straw has rotted, the nitrogen is available again. How to encourage regenerative farming in Europe? Society needs regenerative farming as much as the farmers do – but the market will not pay for it. If we follow the subsidy track, payment by results might be attractive but practical and ethical issues immediately arise. What should those results be? How can they be proven? For instance, we might pay according to improvement in ground cover, soil bulk density and soil organic carbon (easy-to-measure proxies for soil health) (Dent, 2019). But the starting point has to be determined; in the case of soil organic matter, it varies from very low in sandy soils to very high in swamps, and may vary by an order of magnitude within any field. This means a lot of tests. The feasible rate of increase is similarly variable and depends as much on the weather as the farmer; and the gain declines as the soil attains a new equilibrium. When the effective ceiling is reached, is the farmer to be paid simply to maintain it? And is reimbursement to be enforced if it is not maintained, for instance following a change of ownership? We are proposing an alternative, socially well-proven and familiar model based on farmers' actions, not outcomes. It builds upon voluntary associations of farmers that have been the bedrock of regenerative agriculture as a farmers' movement across six continents, such as the Clubs Amigos da Terra in Brazil and the Landcare movement in Australia. The Chianti Classico model The Chianti Classico model is The Chianti Classico model is an alternative, a socially well-proven and familiar model based on farmers' actions, not outcomes. It builds upon voluntary associations of farmers. Chianti Classico is just one among thousands of similar protected names for wine, cheese, ham, etc. throughout Europe that follow similar rules. Essentially, a group of winemakers cooperate, not to make the best wine – that is a matter of fierce individual competition – but to eliminate substandard wine in the expectation that the market will reward them with a higher price. We are proposing local Landcare Groups on similar lines but, since the market will not reward them for farming more sustainably, the new groups will pitch for CAP subsidies. Each group will propose a plan for sustainable farming; a combination of the elements described above appropriate to their circumstances – a plan for the eroded hills of the Val d'Orcia will be different from one for the floodplains of the Chiana, just as Orvieto Classico Superiore is different from Chianti Classico. The group will then add a timetable for implementation and submit the plan to the competent authority for disbursing public funds to support regenerative agriculture. We propose the establishment of a Sustainable Farming Panel for each regional funding body to evaluate these plans. The panel can score the plan on, say, a five-point scale. If the plan is accepted and according to the score awarded, the farmers will receive an annual payment for a period of up to three years to implement it. Payment will be in advance because the costs of change are immediate while the returns and cost savings take time. Most of the payment will be to individual farmers within the group, according to the area proposed for regenerative farming, but 20% may be paid to the group as a whole for education and training, perhaps outside assistance, or as a bonus to members who already have experience of regenerative practices and can serve as mentors. Regenerative farming brand: implementation plan What is a Landcare Group? Like Chianti Classico, it is a legal entity. This is important because the group will be handling public funds. The group is also making promises as a group to the Sustainable Farming Panel. While it is not the same as Chianti Classico and other protected names it should not be difficult to draw up an appropriate legal framework on similar lines. The Landcare Group is not a cooperative, as each farmer farms and sells produce separately. Cooperatives may be formed within the group, particularly for farm machinery, but they are quite separate organisations. The Landcare Group is defined by its objective, which is to maintain a certain standard of regenerative farming. The standard that the group must meet is the standard they put forward in their proposal to the Sustainable Farming Panel, accepted by the panel as sufficient to entitle them to a certain level of subsidy, and subject to review by the panel. For example, a level 1 subsidy may require a 25% reduction in nitrogen fertiliser application and tractor fuel use. Maintaining this standard will entitle the group to the subsidy and this standard will be maintained, firstly, by group action. That is, the group will tell the individual farmer that certain farm practices must change, and they will help to make those changes. Anyone who consistently fails can be expelled but, usually, help from within the group will enable a member to reach the standard. How is a group formed? It may be through existing local farmers' groups, through the encouragement of an accountant or farming adviser, and other ways. Obviously, it needs a commitment to a certain level of sustainable farming. The group is also a source of knowledge that can help other farmers but, if the foundation group is diluted, the core group may be held back as it tries to move up the sustainable farming scale. Guidance on proposals: The Sustainable Farming Panel needs to issue guidance on its priorities for a certain region. For example, the Val d'Orcia in Tuscany is a crisis area for soil erosion, so the guidance will say that proposals must tackle soil erosion as their first priority. It might also suggest measures to improve soil structure such as increasing soil cover and soil organic matter and selective tree planting. This guidance will help groups to formulate their proposals, but it is important to emphasise that the concept is not rigid: guidance is only guidance, not a set of rules. Judging proposals: Over several decades, funding authorities have adopted the competitive approach of the marketplace. If a group of people, or a commune, applies for a subsidy for a new road, a community centre or a theatre group, they will compete for the available funds in the knowledge that funds are limited and not all projects will be funded. The funding authority will receive a suite of well-presented proposals, but the system imposes high costs and risks on those seeking funds: in our case groups of farmers. Farmers need a high level of optimism to be farmers, but they often have a high level of pessimism when it comes to dealing with government agencies. Farmers seeking to become Landcare Groups should not be burdened with extra presentation costs and risks. Moreover, we, the community, want to reduce the climate impact of farming, need to combat floods and drought, need farmers to change. We don't have unlimited funds but must not make the system too expensive and too complicated for farmers. Facing a similar problem in South Australia after three years of severe drought, many famers lacked the cash or credit to sow another crop. The government wanted them to sow the crop because agricultural output was important for the state's economy. So, it provided low-cost loans, but it had to be prudent. Farmers had to provide information to prove the legitimacy of their needs but, as minister of agriculture, Brian Chatterton developed a simpler system to provide a first-step or provisional approval that gave the farmer a strong incentive to provide all the additional information needed to complete the approval. Not one approval was rejected in the second round because the farmer had made the initial application with false information. With this experience, we suggest that a Landcare Group should put forward a proposal in general terms which can be discussed with an Assessment Officer employed by the Sustainable Farming Panel. The officer can then give advice and point out how the proposal needs to be framed to gain approval. From that point, the Landcare Group can be reasonably assured their proposal will be accepted and will have a strong incentive to go ahead and work up the detailed proposal, which would still need to be endorsed by the Sustainable Farming Panel to maintain consistency between the Assessment Officers and to allow proposals that are outside the guidance to be considered. Of course, the bureaucracy would prefer fully complete proposals that can be approved or rejected at one meeting, but the more cooperative approach reduces the risk for the Landcare Groups and, thereby, will bring more of them on board. Monitoring Landcare Groups: Countering land degradation and climate change is imperative so we need to get funding to farmers urgently; the necessary farming changes will take several years to be fully effective. At the same time, we cannot afford to expose millions of euros to fraud. The first and principal means of enforcement is self-assessment. Our experience of self-assessment of the quality of named wines1 suggests that producers are willing and able to make tough decisions to maintain standards. Voluntary systems policed by consent have always proved to be more popular and more effective than command and control. Official checks are, of course, practicable using satellite imagery and, in detail, using UAVs. For example, farmers may promise to tackle bald patches or gullies that can easily be seen and measured on satellite imagery. For examination of actual crop species, an inspector can make a reasonably detailed examination of the cropping pattern of a whole farm in less than an hour using a UAV, and a complete Landcare Group could be checked in a couple of days; but self-policing will be the norm. Cost savings – to the administration: Assessing thousands of individual applications for a regenerative farming subsidy would require a considerable administration, which will be much reduced if farmers apply in Landcare Groups. The groups will be subject to periodic review, not as individual farmers but as groups. Over time, the group might move up the scale or, if they fail to meet their promises, move down; but policing of any individual's adherence to the conditions of the payment can be left to the other members of the group. Members of the Landcare Group cannot avoid assessing their neighbours, but the impact is not so drastic as with the exclusion of a wine from the Chianti Classico label. Cost savings – to the farmers: It is important to consider the cost and risk to farmers in making an application especially if a paid intermediary is employed. The Chianti Classico group approach cuts the cost per hectare and shares these costs among several farmers. Over time, costs are reduced further as farmers join existing Landcare Groups.In the 1960s, European farmers demonstrated that they could change their farming system and produce more food by responding to incentives provided under the CAP. At the same time, these changes also harmed the environment. The farmers will change again if they are offered the appropriate incentives to adopt regenerative farming. The Chianti Classico model is a practical means to do so. References Allan, Toni and Dent, David. "The cost of food: consequences of not valuing soil and water and the people who manage them", in: Dent, David. and Boincean, Boris (ed.) Regenerative agriculture. What's missing? What else do we still need to know? (22 June, 2021). Kassam, Amir. (ed.). Advances in conservation agriculture. Vol. 1-3.Cambridge: Burleigh Dodds Science Publishing, 2020. Crews, Timothy E.; Carton, Wim and Olsson, Lennart. "Is the future of agriculture perennial?Imperatives and opportunities to reinvent agriculture by shifting from annual monocultures toperennial polycultures". Global Sustainability, vol. 1 (2018), p. 1-18. Chatterton, Lynne and Chatterton, Brian. Sustainable Dryland Farming. Cambridge University Press, 2005. King, F H. Farmers of Forty Centuries: Organic Farming in China, Korea and Japan. Mineola NY: Dover Publications, 2004. Panagos, Panos; Ballabo, Cristiano; Poesna, Jean; Lugato, Emmanuel; Scarpa, Simone; Montanarella, Luca and Borrelli, Pasquale. "A soil erosion indicator for supporting agricultural, environment and climate policies in the European Union". Remote Sensing. vol. 12, no. 9 (2020) Dent, David. "A standard for soil health". International Journal of Environmental Studies. vol. 77, no. 4, (November 2019), p. 613-618.Note:1- In the case of appellation d'origin contrôlée (AOC)/denominazione di origin controllata (DOC), nearly all the winemakers in the district, as well as some officials, conduct tastings to establish if they are good enough to bear the all-important name. The wines are awarded a class 1 or 2 which is advisory and has no legal standing. Wines that fail class 2 are graded as Unacceptable. Examination of the voting figures reveals that many wines graded 1 or 2 receive votes of, perhaps, 55% in favour and 45% against but, when it came to the Unacceptable grade, there is not a single wine with less than 90% vote to reject. So, producers are quite capable of making the tough decisions needed to maintain standards. Authors:Brian Chatterton, former Minister of Agriculture in South Australia and farmer in Umbria (Italy)David Dent, former head of the World Soil Association;Martin Keulertz, Lecturer in Environmental Management, University of the West of England, BristolAll the publications express the opinions of their individual authors and do not necessarily reflect the views of CIDOB as an institution.
The objective of the Country Environmental Analysis (CEA) is to assess the adequacy and performance of the policy, legal, and institutional framework for environmental management in Ukraine, in light of the decentralization process of environmental governance and wider reform objectives, and to provide recommendations to government to address the key gaps identified. Ukraine is the second largest country in Europe and has a population of 43 million, the majority of whom live in urban areas. It is a lower middle income country, with the services, industry and agriculture sectors being main contributors to the country's Gross Domestic Product (GDP). Ukraine faces a number of environmental challenges, as identified in its National Environmental Strategy 2020 (NES). Key among these are: air pollution; quality of water resources and land degradation; solid waste management; biodiversity loss; human health issues associated with environmental risk factors; in addition to climate change. The scope of Ukrainian environmental legislation is quite broad and comprehensive (more than 300 legal acts) and covers most areas of environmental protection and natural resources management. However, the environmental legislation faces a number of weaknesses:The environmental legislation is largely declaratory in nature and does not have all the essential enforcement mechanisms for the implementation of legal acts and international agreements; Many of the acts are not coordinated with each other; and Legislation undergoes limited analysis of its impact—for example, no in-depth analysis such as Regulatory Impact Analysis is conducted for proposed pieces of legislation.
What are the socioeconomic impacts of resource abundance? Are these effects different at the national and local levels? How could resource booms benefit (or harm) local communities? This paper reviews a vast literature examining these questions, with an emphasis on empirical works. First, the evidence and theoretical arguments behind the so-called resource curse, and other impacts at the country level, are reviewed. This cross-country literature highlights the importance of institutions. Then, a simple analytical framework is developed to understand how resource booms could impact local communities, and the available empirical evidence is examined. This emerging literature exploits within-country variation and is opening new ways to think about the relation between natural resources and economic development. The main message is that others factors, such as market mechanisms and local spillovers, are also relevant for understanding the impact of resource abundance. Finally, the paper discusses issues related to fiscal decentralization and provides ideas for future research.
The Government of Punjab, through Government of India's (GoI) Department of Economic Affairs (DEA) had requested the World Bank to provide non-lending technical assistance (NLTA) to provide high quality basic urban civic amenities to the residents of cities of Ludhiana and Amritsar in the areas of: water supply, sewerage, storm water drainage, solid waste management, and modern urban transport system. The study is expected to recommend measures and technologies to overcome the existing problems and transform the cities in to modern cities with substantially developed urban civic amenities. Capacity building, institution, and legal reforms will also be the component of the project report. After initial discussions with sector officials, a Bank team visited both Amritsar and Ludhiana cities to identify priority service level innovations and institutional challenges that have to be addressed under this NLTA for achieving desired transformative change. Currently, water supply is drawn from hundreds of unprotected bore wells across length and breadth of the city - which supply polluted water through an unplanned haphazard network. Utility, fully owned by the municipal corporation, will have operational autonomy to manage water and waste water services, whilst still be accountable to the corporation. Financial position will become clear, it can focus on becoming financially self-sustaining. The utility will make long term plans for water supply and sewage; and with government support may also be able to mobilize resources through this is unlikely in the short term in Amritsar.
Currently biofuels have strong political support, both in the EU and Sweden. The EU has, for example, set a target for the use of renewable fuels in the transportation sector stating that all EU member states should use 10% renewable fuels for transport by 2020. Fulfilling this ambition will lead to an enormous market for biofuels during the coming decade. To avoid increasing production of biofuels based on agriculture crops that require considerable use of arable area, focus is now to move towards more advanced second generation (2G) biofuels that can be produced from biomass feedstocks associated with a more efficient land use. Climate benefits and greenhouse gas (GHG) balances are aspects often discussed in conjunction with sustainability and biofuels. The total GHG emissions associated with production and usage of biofuels depend on the entire fuel production chain, mainly the agriculture or forestry feedstock systems and the manufacturing process. To compare different biofuel production pathways it is essential to conduct an environmental assessment using the well-to-tank (WTT) analysis methodology. In Sweden the conditions for biomass production are favourable and we have promising second generation biofuels technologies that are currently in the demonstration phase. In this study we have chosen to focus on cellulose based ethanol, methane from gasification of solid wood as well as DME from gasification of black liquor, with the purpose of identifying research and development potentials that may result in improvements in the WTT emission values. The main objective of this study is thus to identify research and development challenges for Swedish biofuel actors based on literature studies as well as discussions with the the researchers themselves. We have also discussed improvement potentials for the agriculture and forestry part of the WTT chain. The aim of this study is to, in the context of WTT analyses, (i) increase knowledge about the complexity of biofuel production, (ii) identify and discuss improvement potentials, regarding energy efficiency and GHG emissions, for three biofuel production cases, as well as (iii) identify and discuss improvement potentials regarding biomass supply, including agriculture/forestry. The scope of the study is limited to discussing the technologies, system aspects and climate impacts associated with the production stage. Aspects such as the influence on biodiversity and other environmental and social parameters fall beyond the scope of this study. We find that improvement potentials for emissions reductions within the agriculture/forestry part of the WTT chain include changing the use of diesel to low-CO2-emitting fuels, changing to more fuel-efficient tractors, more efficient cultivation and manufacture of fertilizers (commercial nitrogen fertilizer can be produced in plants which have nitrous oxide gas cleaning) as well as improved fertilization strategies (more precise nitrogen application during the cropping season). Furthermore, the cultivation of annual feedstock crops could be avoided on land rich in carbon, such as peat soils and new agriculture systems could be introduced that lower the demand for ploughing and harrowing. Other options for improving the WTT emission values includes introducing new types of crops, such as wheat with higher content of starch or willow with a higher content of cellulose. From the case study on lignocellulosic ethanol we find that 2G ethanol, with co-production of biogas, electricity, heat and/or wood pellet, has a promising role to play in the development of sustainable biofuel production systems. Depending on available raw materials, heat sinks, demand for biogas as vehicle fuel and existing 1G ethanol plants suitable for integration, 2G ethanol production systems may be designed differently to optimize the economic conditions and maximize profitability. However, the complexity connected to the development of the most optimal production systems require improved knowledge and involvement of several actors from different competence areas, such as chemical and biochemical engineering, process design and integration and energy and environmental systems analysis, which may be a potential barrier. Three important results from the lignocellulosic ethanol study are: (i) the production systems could be far more complex and intelligently designed than previous studies show, (ii) the potential improvements consist of a large number of combinations of process integration options wich partly depends on specific local conditions, (iii) the environmental performance of individual systems may vary significantly due to systems design and local conditons. From the case study on gasification of solid biomass for the production of biomethane we find that one of the main advantages of this technology is its high efficiency in respect to converting biomass into fuels for transport. For future research we see a need for improvements within the gas up-grading section, including gas cleaning and gas conditioning, to obtain a more efficient process. A major challenge is to remove the tar before the methanation reaction. Three important results from the biomethane study are: (i) it is important not to crack the methane already produced in the syngas, which indicates a need for improved catalysts for selective tar cracking, (ii) there is a need for new gas separation techniques to facilitate the use of air oxidation agent instead of oxygen in the gasifier, and (iii) there is a need for testing the integrated process under realistic conditions, both at atmospheric and pressurized conditions. From the case study on black liquor gasification for the production of DME we find that the process has many advantages compared to other biofuel production options, such as the fact that black liquor is already partially processed and exists in a pumpable, liquid form, and that the process is pressurised and tightly integrated with the pulp mill, which enhances fuel production efficiency. However, to achieve commercial status, some challenges still remain, such as demonstrating that materials and plant equipment meet the high availability required when scaling up to industrial size in the pulp mill, and also proving that the plant can operate according to calculated heat and material balances. Three important results from the DME study are: (i) that modern chemical pulp mills, having a potential surplus of energy, could become important suppliers of renewable fuels for transport, (ii) there is a need to demonstrate that renewable DME/methanol will be proven to function in large scale, and (iii) there is still potential for technology improvements and enhanced energy integration. Although quantitative improvement potentials are given in the three biofuel production cases, it is not obvious how these potentials would affect WTT values, since the biofuel production processes are complex and changing one parameter impacts other parameters. The improvement potentials are therefore discussed qualitatively. From the entire study we have come to agree on the following common conclusions: (i) research and development in Sweden within the three studied 2G biofuel production technologies is extensive, (ii) in general, the processes, within the three cases, work well at pilot and demonstration scale and are now in a phase to be proven in large scale, (iii) there is still room for improvement although some processes have been known for decades, (iv) the biofuel production processes are complex and site specific and process improvements need to be seen and judged from a broad systems perspective (both within the production plant as well as in the entire well-to-tank perspective), and (v) the three studied biofuel production systems are complementary technologies. Futher, the process of conducting this study is worth mentioning as a result itself, i.e. that many different actors within the field have proven their ability and willingness to contribute to a common report, and that the cooperation climate was very positive and bodes well for possible future collaboration within the framework of the f3 center. Finally, judging from the political ambitions it is clear that the demand for renewable fuels will significantly increase during the coming decade. This will most likely result in opportunities for a range of biofuel options. The studied biofuel options all represent 2G biofuels and they can all be part of the solution to meet the increased renewable fuel demand.
This report presents a concise review of the major environmental and natural resources issues at the global and national level over the coming two decades. The environmental issues reviewed include air pollution and deterioration of air quality, greenhouse gas emissions and climate change, water quality, scarcity and access, land and soil degradation, deforestation and forest degradation, natural disaster, loss of biodiversity and protected areas, and governance and institutions for environmental and natural resource management. Besides providing an environment outlook, the report tackles the issue of monitoring also from the supply side. It identifies the relevant data and indicator sets available at the global level and country level to capture the global and locally relevant environmental issues with the underlying objective of pinpointing at data gaps. It concludes with a set of recommendations for moving forward on the monitoring agenda. Overall, the threats from climate change caused by Green House Gas (GHG) emissions, biodiversity loss, water pollution and scarcity as well as pressure on land as well as worsening ocean's state and biodiversity have to be taken under close observation in the period over the next 20 years. The environment challenges that the world faces are not trivial and some of them require immediate action. Action, in turn, requires reliable and accurate information. The second part of the report looks at information from the supply side. It identifies the relevant data and indicator sets available at the global level and country level to capture the global and locally relevant environmental issues with the underlying objective of informing and advising decision making and to identify the data gaps.
During the past decade, Georgia's pursuit of economic reforms led to impressive economic growth, capital inflow, and investments. It helped improve the business environment and infrastructure, strengthened public finances, and liberalized trade. Georgia achieved most of the human development targets of the Millennium Development Goals (MDGs). This progress did not result, however, in improved environmental governance or better management of natural resources. Nowadays, environmental policies are receiving increasing attention from Georgian policy and decision makers, recognizing that sustainable development is about a profound change of policies that drive systemic transformation of production, consumption, and behavioral patterns. The list of the country's environmental challenges is long. Current policies and instruments lack the rigor to effectively reduce pressures on natural assets and protect public health from poor environmental quality. Georgia does not have a comprehensive assessment of the cost of inaction to environmental degradation linking it to economic growth, poverty, and shared prosperity. This is a central issue on which the Country Environmental Analysis (CEA) is focused. The main objective of the CEA is to assist the government, civil society, and development partners of Georgia in identifying and analyzing critical environmental constraints to sustainable growth and shared prosperity. Georgia's Country Partnership Strategy for 2014-2017 points to lagging public policies on protecting the environment and natural resources, against impressive economic growth. It further highlights several areas needing attention, such as air and water quality, waste management, land and landscape management, and nature resource use and protection.
Käesoleva magistritöö eesmärgiks oli analüüsida kõnealuse ettevõtte tootmise vastavusse viimist tööstusheite direktiivi 2010/75/EU ja parima võimaliku tehnika nõuetega. Tööstusheite direktiiv 2010/75/EU (THD) võeti vastu 2010. aastal ning jõustus aastal 2011. Nimetatud dokument kehtestab PVT rakendamise kohustuse. Tööstusheite seadusega kehtestatakse heidete piirväärtused, mis on tolmu, NOx, SOx ja lenduvate orgaaniliste ühendite osas varasemast rangemad. Kunda Nordic Tsement on Kunda suurim tööstusettevõte, mille tootmistegevus põhjustab piirkonnas välisõhu saastatust, seda eelkõige peentolmu (ületamine CO väljalöökide tõttu), vääveldioksiidi (ületamine ca 180 mg/Nm3 võrra) ja lämmastikdioksiidi (ületamine ca 100 mg/Nm3 võrra) osas, pikemas perspektiivis osutuvad probleemideks ka vesinikkloriidi (HCl) ja lenduvate orgaaniliste ühendite heitkogused. Energiakulust tulenevalt on parimaks lahenduseks minna märgmenetluselt üle kuivmenetlusel töötavale tehasele, mille energiakulu on kaks korda madalam. Ettevõtte edasise töö jätkamiseks on vaja koostada ka lähteolukorra aruanne, kompleksloa taotlus kuivale ahjuliinile, saasteainete heitkoguste vähendamise tegevuskava ning taotleda ehitusluba. Majanduslikust aspektist tuleb hinnata investeeringuid heitepüüdeseadmetele. Tolmuheite vähendamise lahendusena tuleb rekonstrueerida elektrostaatiline sadestaja (ESP). NOx heite püüdmiseks sobib märja menetluse puhul selektiivne katalüütiline taandamine (SCR) ning kuiva menetlusega ahju puhul selektiivne mittekatalüütiline taandamine (SNCR). SOx heite vähendamise sobivaimaks variandiks on absorbendi lisamise meetod. Kui tehas jätkab tegevust märgmenetlusmeetodil, oleks heitepüüdeseadmetesse investeerimise vajadus hinnanguliselt 16 miljonit eurot, kuid energiakulu liiga suure hulga tõttu kompleksluba taotleda ei õnnestuks. Kuivmenetlusele üle minnes langeksid investeeringud heitepüüdeseadmetele 11 miljoni euroni kuid lisandub investeerimisvajadus uude tehnoloogiasse, kogumaksumusega hinnanguliselt 57 miljonit eurot. ; This master thesis in "Implementation of Industrial Emission Act in Kunda Nordic Tsement AS" is intended to analyze company's manufacture adjustment with industrial emissions directive 2010/75/EU and best available technique (BAT) requirements. 24. April 2013, the Estonian parliament adopted Industrial Emissions Act, which came into force the same year, 1st of June. The Act regulates activities about certain industrial sectors and replaced the earlier Integrated Pollution Prevention and Control Act (IPPC). Subject is important due to the requirements of Directive 2010/75/EU on Industrial Emissions in line with the deadlines. Companies, that already have the commitment for the integrated environmental permit, have the transitional period for four years to apply BAT, but not later than 09. April 2017. Industrial Emissions Directive 2010/75/EU (IED) was adopted in 2010, and entered into force in 2011. Directive also imposes an obligation to implement BAT, which enforcement is based on Best Available Technique Reference Document (BREF) for cement, lime and magnesium oxide production (EC, 2013). Industrial emissions law also establishes emission limits for dust, NOx, SOx and volatile organic compunds, that are more stringent, than in the past. SOx emission limit was 1500 mg/Nm3 but new law established limit for 50 mg/Nm3 . Before IED adopted, NOx emission limit was 800 mg/Nm3 , since year 2014, it's 500mg/Nm3 . Limit for volatile organic compounds was 50 mg/Nm3 , IED established limit for 10 mg/Nm3 . For dust, the limit used to be 50 mg/Nm3 , after year 2014, it is 30 mg/Nm3 . In collaboration with Kunda Nordic Tsement AS, dust studies have been carried out since 1994. In addition NO, NO2, NOx, and SO2 measurements were added. The studies are carried out by Estonian Environmental Research Centre. Kunda Nordic ! #< Tsement is Kunda's largest industrial company, which manufacturing activity causes air pollution in the area, especially fine dust (because of CO trips), sulfur dioxide (excess is about 180mg/Nm3 ) and nitrogen dioxide (excess is about 100mg/Nm3 ), in the long run, problems turn out to be hydrogen chloride (HCl) and volatile organic compounds emissions. The largest quantities of dust emerge from rotary kilns, but these problems do not occur in annual measurements averages. Based on the number of CO trips recorded and analyzing pollutant monitoring system, current abatement equipment do not satisfy standards, allowed by IED. Not to mention values that will be inure in 2020. The BREF and Industrial Emissions Act set out different ways to lead company's operations amounts of pollutants into compliance, for example, if the raw material or fuel contains large amounts of sulfur or nitrogenous compounds. One important aspect is the amount of heat energy used per tone of produced clinker. Wet process uses twice as much energy as allowed in BAT. The best solution due to the energy consumption is to switch processes from wet kiln to dry kiln. Integrated environmental permit can't be applied if production don't meet environmental requirements. For the further work, it's necessary to establish a baseline report, integrated environmental permit for the dry kiln, pollutant emission reduction action plan and apply for a building permit. From an economic point of view, it's important to pay attention to abatement equipment. Solution for the dust emission is electrostatic precipitator (ESP) reconstruction. Textile- and hybrid filters were excluded, because textiles can't stand high temperatures. For the wet process NOx emissions catching is suitable selective catalytic reduction (SCR) and for the dry process kiln selective non-catalytic reduction (SNCR). Due to different temperatures and optimum operation mode, different methods are needed. The most suitable option for SOx reduction is absorbent addition. BREF recommended also wet scrubbing method, with a consequent need for a wastewater treatment, due to which the device is not suitable. If the plant continues to operate with wet process, estimated needed investment would be 16 million Euros, but due to too high-energy consumption, integrated environmental permit can't be applied if production don't meet environmental ! #; requirements. If the plant goes over to dry process kiln, estimated costs will be 57 million Euros, which includes investment in new technology and reconstruction of abatement equipment. It will be necessary to build tumble dryer, raw material silo, replace wet kiln to dry kiln with preheater and pre-calciner, also energy management and process control.
Front Matter -- Physical Metallurgy of Steel. Influence of the Hot Rolling Process on the Mechanical Behaviour of Dual Phase Steel / Mehdi Asadi, Heinz Palkowski -- Continuous Casting Simulation of 2304 Duplex Stainless Steel Via Horizontal Directional Solidification Technique / Qingqing Sun, Honggang Zhong, Xiangru Chen, Qijie Zhai -- Influence of Cooling Rates on Nitrogen Precipitation Behaviors and the Ferrite Fraction in Cast 2507 Super Duplex Stainless Steel / Dong Liang, Honggang Zhong, Zhenxing Yin, Qijie Zhai -- Microstructure and Corrosion Behaviour of TiC Reinforced Duplex Stainless Steels Matrix Composites Synthesized by Laser Melt Injection / Babatunde Obadele, Peter Olubambi, Oluwagbenga Johnson -- Process Metallurgy of Metals. A Critical Review of the Modified Froude Number in Ladle Metallurgy / K Krishnapisharody, G A irons -- Inclusion Characteristics in Stainless Steel Ingots / Shufeng Yang, Lifeng Zhang, Yongfeng Chen, Jun Ge, Greg Dowling, George Shannon -- FEM Study of Centerline Defect Closure in Large Open-Die Forgings / Jie Zhou, Joshua Blackketter, Philip Nash -- Effect of Mould Taper and Wall Thickness on Steel Ingots Soundness by 3-D Solidification Simulation / Peng Lan, Yang Li, Jiaquan Zhang, Ruitian Zhang, Jingyuan Wang, Hengyi Zhang -- Hydrometallurgical Study of Purifying M-G Silicon Feedstock for Solar Cells Production / Yongqiang Liu, Jilai Xue, Jun Zhu -- The Effect of Fe Addition on the Activity of Si in Liquid Cu-Si Alloys / Yuichi Kato, Takeshi Yoshikawa, Kazuki Morita -- Thermodynamic Properties of the Silicon Binary Melts / Jafar Safarian, Leiv Kolbeinsen, Merete Tangstad -- Application of Microwave, Magnet, Laser and Plasma Technology. Non-Contact Measurements in Liquid Metal Free-Surface Flow Using Time-of-Flight Lorentz Force Velocimetry / Dandan Jian, Christian Karcher -- Modeling of Pulsed-Laser Superalloy Powder Deposition Using Moving Distributed Heat Source / M M Mahapatra, Leijun Li -- Heat Transfer Characteristics of Magnetite under Microwave Irradiation / Zhiwei Peng, Jiann-Yang Hwang, Matthew Andriese, Zheng Zhang, Xiaodi Huang -- Refinement Effect of Pulse Magneto-Oscillation on Solidification Structure of Medium Carbon Steel / Yufeng Cheng, Zhenxing Yin, Xin Cao, Yongyong Gong, Renxing Li, Qijie Zhai -- Solidification Structure Refinement of SUS430 Ferritic Stainless Steel by Electric Current Pulse / Xin Cao, Zhenxing Yin, Yufeng Cheng, Renxing Li, Yongyong Gong, Qijie Zhai -- Metallurgy of Non-Ferrous Metals. Annealing Effect and Tensile Interface Fracture Mechanism of Pure Silver Bonding Wires / Hao-Wen Hsueh, Fei-Yi Hung, Truan-Sheng Lui, Li-Hui Chen -- Horizontal Directional Solidification of Zn-Al Alloys / Marco Zurco, Carlos M Rodriguez, Carlos E Schvezov, Claudia M Mendez, Alicia E Ares -- Dynamic Recovery during Low Temperature Deformation in an Al-0.1 Mg Alloy / Y Huang, P B Prangnell -- Challenges in Compound Forging of Steel-Aluminum Parts / Klaus-Georg Kosch, Bernd-Arno Behrens -- Poster Session. Effect of Process Parameters on Powdering Characteristics of Galvannealed Materials / Khursid Alam Khan, R J Singh, Shantanu Chakrabarti -- Hot Deformation Behavior of Nb Microalloyed Coiled Tubing Steel / Zhendong Zhang, Haitao Zhou, Xianghua, Liu, Sijun Li, Guofei Si, Bingyu Zhang -- Study on Inclusions in 65Mn Thin Slabs Produced by a CSP Process / Tan Yi, Honggang Zhong, Zhao Dan, Xinping Mao, Qijie Zhai, Huigai Li -- A Way to Control Distortion of Metal Parts during Heat Treatment Process / Yuan Lu, Jinwu Kang, Haimin Long, Gang Nie, Tianyou Huang -- Investigation of the Relationship of the Melt Structures and Solidification Behaviors of Cu-Sb70 Alloy Explored by Electrical Resistivity Method / Yun Xi, Jin Yu, Li-Na Mao, Fang-Qiu Zu -- Microstructure of AlO/YAG/ZrO Eutectic Composite Prepared by Laser Floating Zone Melting / Kan Song, Jun Zhang, Xiaojiao Jia, Haijun Su, Lin Liu, Hengzhi Fu -- Net Shape Manufacturing of a Novel Cermet Using Self-Propagating High Temperature Synthesis / Atefeh Nabavi, Alexander Cappozi, Sam Goroshin, David Frost, Francois Barthelat -- Electronics. Control of Gas Emission during Pyrolysis of Waste Printed Wiring Boards / Alex Luyima, Lifeng Zhang, Jaan Kers, Thomas Schuman -- Leaching Studies for Metals Recovery from Waste Printed Wiring Boards (PWBs) / Alex Luyima, Honglan Shi, Lifeng Zhang, Yongqing Jiang -- Effects of Inoculums Volume on Metals Extraction from Printed Circuit Boards of Computers by Bacterial Leaching / Luciana Harue Yamane, Denise Crocce Romano Espinosa, Jorge Alberto Soares Tenorio -- Removal of Copper Cyanide Complexes from Solutions Formed in Silver/Gold-Cyanidation Recovery Process / Jose R Parga, Jesus L Valenzuela, Luciano E Ramirez -- Dissolution of Mixed Zinc-Carbon and Alkaline Battery Powders in Sulphuric Acid Using Ascorbic/Oxalic Acid as a Reductant / Muammer Kaya, Sait Kursunoglu -- Selective Recovery of Precious Metals by Selective Adsorption on Garlic Peel Gel / Kai Huang, Shuqiang Jiao, Hongmin Zhu -- Separation of Si/SiC Wiresaw Cutting Powder Through Sedimentation by Adjusting the Solution pHs / Kai Huang, Hao Deng, Jichao Li, Hongmin Zhu -- Metals. Advantages of Integrated and Long Term Aluminum Recycling Batch Planning in a Constrained Secondary Material Market / Tracey Brommer, Elsa Olivetti, Britt Elin Gihleengen, Randolph Kirchain -- Fabrication of Replicated Open-cell Aluminium Foams Using Recycled ADC12 Aluminium Alloy / Seksak Asavavisithchai, Natthida Jareankieathbovorn, Areeya Srichaiyaperk -- In-Process Separation of Mill Scale From Oil at Steel Hot Rolling Mills / Naiyang Ma -- Recycling of Electric Arc Furnace Dust: Evaluation of the Iron Metal Incorporation in Hot Metal Bath / Vicente de Paulo Ferreira Marques Sobrinho, Jose Roberto de Oliveira, Victor Bridi Teiles, Felipe Fardin Grillo, Jorge Alberto Soares Tenorio, Denise Crocce Romano Espinosa -- Recycling of Electric Arc Furnace Dust in Iron Ore Sintering / V B Teiles, D C R Espinosa, J A S Tenorio -- Extraction of Iron Oxide and Concentration of Titanium Compounds in Red Mud / Edilson Marques Magalh̃es, Emanuel Negr̃o Macedo, Danielly Da Silva Quaresma, Jose Antonio da Silva Souza, Jõo Nazareno Nonato Quaresma -- Heat Treatment of Black Dross for the Production of a Value Added Material-A Preliminary Study / Reza Beheshti, Shahid Akhtar, Ragnhild E Aune -- Addition of Electric Arc Furnace Dusts in Hot Metal / TMS, Msc Felipe Fardin Grillo, PhD Jose Roberto de Oliveira, PhD Denise Crocce Romano Espinosa, PhD Jorge Alberto Soares Tenorio -- Building Materials. Ecological Recovery Process for Textile Waste / Eftalea Carpus, Emilia Visileanu, Michaela Dina Stanescu -- Technical Tools for Increasing the Eco-Efficiency of Textile Products / Emilia Visileanu, Eftalea Carpus -- An Evaluation Study: Recent Developments and Processing of Glass Scrap Recycling / Burcu Ertug, Nectp Unlu
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Мета. Моделювання умов досягнення «поворотної точки» в моделі екологічної кривої Кузнеця (ЕКК) для умов економіки України.Методи. Використані загальнонаукові (аналіз та синтез, індукція та дедукція, аналітичне групування) та спеціальні (абстрагування, моделювання і т. ін.) методи вивчення економічних явищ і процесів.Результати. Задля визначення умов сталого розвитку національного господарства запропоновано використати галузевий підхід. В його основу покладено ідею, що досягти стійкого поворотного моменту у моделі ЕКК для України можливо шляхом управління її параметрами на рівні провідних галузей економіки. Такими галузями для України є такі: переробна; добувна і розроблення кар'єрів; сільське, лісове та рибне господарство; постачання електроенергії, газу, пари та кондиційованого повітря; транспорт, складське господарство, пошта та кур'єрська служба. Доведено, що причини недосягнення стійкого поворотного моменту полягають в тому, що гальмуючий вплив здійснює добувна галузь; транспорт, складське господарство, пошта та кур'єрська служба й сільське, лісове та рибне господарство. Показано, що пріоритетними для розвитку економіки України є переробна галузь та енергетика, оскільки саме в них є переважні економічні умови отримання вищого рівня доданої вартості в порівнянні з добувною галуззю, а сільськогосподарський потенціал України можливо використати в разі підвищення рівня оплати праці персоналу галузі. Встановлено, що негативні тенденції у транспортній галузі пов'язані із низькою екологічністю транспортних засобів, що використовуються в Україні і, як наслідок, збільшення останніми роками обсягів викидів шкідливих речовин.Висновки. Доведено, що ЕКК для України може бути побудована на основі взаємозв'язку між обсягами викидів діоксида сірки, діоксида азоту, оксида, діоксида вуглецю й доходом на душу населення України. Встановлено, що крива Кузнеця в умовах України має «точковий» характер. Запропоновано ЕКК, побудовану на основі взаємозв'язку між обсягами викидів шкідливих речовин та величиною середнього номінального доходу на одного працюючого у провідних галузях національного господарства. Доведено, що забезпечити сталий розвиток економіки України можливо шляхом екологізації виробництва в межах наявної структури національної економіки на основі використання галузевих капітальних інвестицій та активізації державної підтримки природоохоронних заходів. ; Purpose. The study objective was to model the conditions to reach the "turning point" in the environmental Kuznets curve model (EKC) for the Ukrainian economy.Меthods. In the research general scientific (analysis and synthesis, induction and deduction, analytical grouping) and special (abstraction, modelling, etc.) methods of studying economic phenomena and processes have been used.Results. To determine the conditions for maintaining sustainable development of the national economy, it has been proposed to use sectoral approach. It is based on the idea that to reach the sustainable turning point in the EKC model for Ukraine, key parameters of its leading economic sectors have to be managed. Such industries for Ukraine are: processing; mining and quarry development; agriculture, forestry and fisheries; supply of electricity, gas, steam and conditioned air; transport, warehousing, post and courier service. It has been proved that sustainable turning point was not reached because mining, transport, warehousing, post and courier services, agriculture, forestry and fisheries put back. It has been demonstrated that processing industry and energy are the priority sectors for the development of Ukraine's economy, because they have the predominant economic conditions to get higher added value compared with mining, and Ukraine's agricultural capacity could be used to increase wages of the sector`s staff. It has been determined that transport sector`s negative trends are explained by few environmentally friendly vehicles in Ukraine and, as a result, higher recent emissions of air pollutants.Conclusions. It has been proved that EKC for Ukraine could be built on the basis of correlation between sulfur dioxide, nitrogen dioxide, oxide, carbon dioxide emissions and income per capita in Ukraine. It has been found out that Kuznets curve in Ukraine is "point"-like. The EKC based on correlation between emissions of air pollutants and average nominal income per capita in the leading sectors of the national economy has been proposed. It has been proved that it is possible to ensure sustainable development of Ukraine's economy by greening production within the existing structure of the national economy based on sectoral capital investment and intensification of government support policy of environment. ; Цель. Моделирование условий достижения «поворотной точки» в модели экологической кривой Кузнеца (ЭКК) для условий экономики Украины. Методы. Использованы общенаучные (анализ и синтез, индукция и дедукция, аналитическое группировки) и специальные (абстрагирование, моделирование и т. Д.) Методы изучения экономических явлений и процессов.Результаты. Для определения условий устойчивого развития национального хозяйства предложено использовать отраслевой подход. В его основу положена идея, что достичь устойчивого поворотного момента в модели ЭКК для Украины возможно путем управления ее параметрами на уровне ведущих отраслей экономики. Такими отраслями для Украины являются: перерабатывающая; добывающая и разработки карьеров; сельское, лесное и рыбное хозяйство; поставки электроэнергии, газа и кондиционированного воздуха; транспорт, складское хозяйство, почта и курьерская служба. Доказано, что причины недостижения устойчивого поворотного момента заключаются в том, что тормозящее влияние осуществляет добывающая отрасль; транспорт, складское хозяйство, почта и курьерская служба и сельское, лесное и рыбное хозяйство. Показано, что приоритетными для развития экономики Украины является перерабатывающая отрасль и энергетика, поскольку именно в них предпочтительны экономические условия получения высшего уровня добавленной стоимости по сравнению с добывающей отраслью, а сельскохозяйственный потенциал Украины возможно использовать в случае повышения уровня оплаты труда персонала отрасли. Установлено, что негативные тенденции в транспортной отрасли связаны с низкой экологичностью транспортных средств, используемых в Украине и, как следствие, увеличение в последние годы объемов выбросов вредных веществ.Выводы. Доказано, что ЕКК для Украины может быть построена на основе взаимосвязи между объемами выбросов диоксида серы, диоксида азота, оксида, диоксида углерода и доходом на душу населения Украины. Установлено, что кривая Кузнеца в условиях Украины имеет «точечный» характер. Предложено ЭКК, построенную на основе взаимосвязи между объемами выбросов вредных веществ и величиной среднего номинального дохода на одного работающего в ведущих отраслях национального хозяйства. Доказано, что устойчивое развитие экономики Украины возможно путем экологизации производства в пределах существующей структуры национальной экономики на основе использования отраслевых капитальных инвестиций и активизации государственной поддержки природоохранных мероприятий.
Мета. Моделювання умов досягнення «поворотної точки» в моделі екологічної кривої Кузнеця (ЕКК) для умов економіки України.Методи. Використані загальнонаукові (аналіз та синтез, індукція та дедукція, аналітичне групування) та спеціальні (абстрагування, моделювання і т. ін.) методи вивчення економічних явищ і процесів.Результати. Задля визначення умов сталого розвитку національного господарства запропоновано використати галузевий підхід. В його основу покладено ідею, що досягти стійкого поворотного моменту у моделі ЕКК для України можливо шляхом управління її параметрами на рівні провідних галузей економіки. Такими галузями для України є такі: переробна; добувна і розроблення кар'єрів; сільське, лісове та рибне господарство; постачання електроенергії, газу, пари та кондиційованого повітря; транспорт, складське господарство, пошта та кур'єрська служба. Доведено, що причини недосягнення стійкого поворотного моменту полягають в тому, що гальмуючий вплив здійснює добувна галузь; транспорт, складське господарство, пошта та кур'єрська служба й сільське, лісове та рибне господарство. Показано, що пріоритетними для розвитку економіки України є переробна галузь та енергетика, оскільки саме в них є переважні економічні умови отримання вищого рівня доданої вартості в порівнянні з добувною галуззю, а сільськогосподарський потенціал України можливо використати в разі підвищення рівня оплати праці персоналу галузі. Встановлено, що негативні тенденції у транспортній галузі пов'язані із низькою екологічністю транспортних засобів, що використовуються в Україні і, як наслідок, збільшення останніми роками обсягів викидів шкідливих речовин.Висновки. Доведено, що ЕКК для України може бути побудована на основі взаємозв'язку між обсягами викидів діоксида сірки, діоксида азоту, оксида, діоксида вуглецю й доходом на душу населення України. Встановлено, що крива Кузнеця в умовах України має «точковий» характер. Запропоновано ЕКК, побудовану на основі взаємозв'язку між обсягами викидів шкідливих речовин та величиною середнього номінального доходу на одного працюючого у провідних галузях національного господарства. Доведено, що забезпечити сталий розвиток економіки України можливо шляхом екологізації виробництва в межах наявної структури національної економіки на основі використання галузевих капітальних інвестицій та активізації державної підтримки природоохоронних заходів. ; Purpose. The study objective was to model the conditions to reach the "turning point" in the environmental Kuznets curve model (EKC) for the Ukrainian economy.Меthods. In the research general scientific (analysis and synthesis, induction and deduction, analytical grouping) and special (abstraction, modelling, etc.) methods of studying economic phenomena and processes have been used.Results. To determine the conditions for maintaining sustainable development of the national economy, it has been proposed to use sectoral approach. It is based on the idea that to reach the sustainable turning point in the EKC model for Ukraine, key parameters of its leading economic sectors have to be managed. Such industries for Ukraine are: processing; mining and quarry development; agriculture, forestry and fisheries; supply of electricity, gas, steam and conditioned air; transport, warehousing, post and courier service. It has been proved that sustainable turning point was not reached because mining, transport, warehousing, post and courier services, agriculture, forestry and fisheries put back. It has been demonstrated that processing industry and energy are the priority sectors for the development of Ukraine's economy, because they have the predominant economic conditions to get higher added value compared with mining, and Ukraine's agricultural capacity could be used to increase wages of the sector`s staff. It has been determined that transport sector`s negative trends are explained by few environmentally friendly vehicles in Ukraine and, as a result, higher recent emissions of air pollutants.Conclusions. It has been proved that EKC for Ukraine could be built on the basis of correlation between sulfur dioxide, nitrogen dioxide, oxide, carbon dioxide emissions and income per capita in Ukraine. It has been found out that Kuznets curve in Ukraine is "point"-like. The EKC based on correlation between emissions of air pollutants and average nominal income per capita in the leading sectors of the national economy has been proposed. It has been proved that it is possible to ensure sustainable development of Ukraine's economy by greening production within the existing structure of the national economy based on sectoral capital investment and intensification of government support policy of environment. ; Цель. Моделирование условий достижения «поворотной точки» в модели экологической кривой Кузнеца (ЭКК) для условий экономики Украины. Методы. Использованы общенаучные (анализ и синтез, индукция и дедукция, аналитическое группировки) и специальные (абстрагирование, моделирование и т. Д.) Методы изучения экономических явлений и процессов.Результаты. Для определения условий устойчивого развития национального хозяйства предложено использовать отраслевой подход. В его основу положена идея, что достичь устойчивого поворотного момента в модели ЭКК для Украины возможно путем управления ее параметрами на уровне ведущих отраслей экономики. Такими отраслями для Украины являются: перерабатывающая; добывающая и разработки карьеров; сельское, лесное и рыбное хозяйство; поставки электроэнергии, газа и кондиционированного воздуха; транспорт, складское хозяйство, почта и курьерская служба. Доказано, что причины недостижения устойчивого поворотного момента заключаются в том, что тормозящее влияние осуществляет добывающая отрасль; транспорт, складское хозяйство, почта и курьерская служба и сельское, лесное и рыбное хозяйство. Показано, что приоритетными для развития экономики Украины является перерабатывающая отрасль и энергетика, поскольку именно в них предпочтительны экономические условия получения высшего уровня добавленной стоимости по сравнению с добывающей отраслью, а сельскохозяйственный потенциал Украины возможно использовать в случае повышения уровня оплаты труда персонала отрасли. Установлено, что негативные тенденции в транспортной отрасли связаны с низкой экологичностью транспортных средств, используемых в Украине и, как следствие, увеличение в последние годы объемов выбросов вредных веществ.Выводы. Доказано, что ЕКК для Украины может быть построена на основе взаимосвязи между объемами выбросов диоксида серы, диоксида азота, оксида, диоксида углерода и доходом на душу населения Украины. Установлено, что кривая Кузнеца в условиях Украины имеет «точечный» характер. Предложено ЭКК, построенную на основе взаимосвязи между объемами выбросов вредных веществ и величиной среднего номинального дохода на одного работающего в ведущих отраслях национального хозяйства. Доказано, что устойчивое развитие экономики Украины возможно путем экологизации производства в пределах существующей структуры национальной экономики на основе использования отраслевых капитальных инвестиций и активизации государственной поддержки природоохранных мероприятий.
