Suchergebnisse

This contribution presents a simple and fast Synthetic Aperture Radar (SAR)-based technique for microwave imaging and material characterization from microwave measurements acquired in tomographic systems. SAR backpropagation is one of the simplest and fastest techniques for microwave imaging. However, in the case of heterogeneous objects and media, a priori information about the constitutive parameters (conductivity, permittivity) is needed for an accurate imaging. In some cases, a first guess of the constitutive parameters can be extracted from an uncorrected SAR image, and then the estimated parameters can be introduced in a second step to correct the SAR image. The main advantage of this methodology is that there is little or no need for a priori information about the object to be imaged. Besides, calculation time is not significantly increased with respect to conventional SAR, thus allowing real-time imaging capabilities. The methodology has been validated by means of measurements acquired in a cylindrical setup. ; This research was partially supported by the "Ministerio de Economía y Competitividad" of Spain/FEDER under grant FPU15/06341; by the Principado de Asturias under project GRUPINN-18-000191; and by the European Union under the framework of the Erasmus+ mobility agreement between the University of Oviedo (E OVIEDO 01) and Hochschule Mannheim (D MANNHEI 03).

Diagnosis of stable coronary artery disease is vital for prognosis, classification and early treatment. Current guidelines show that patients with stable angina who are suspected of CAD need to undergo a certain protocol for classification and further analysis. This review's aim is to present the most used non-invasive techniques for identification of CAD and to underline the current development of imaging technology and the possible reduction of invasive measures due to non-invasive techniques. Currently, non-invasive techniques used to diagnose stable coronary artery disease have a very high accuracy and newer methods seem to be comparable to the gold-standard. The majority of the methods discussed have an optimal performance for patients with PTP between 15-85%, and the future of diagnosis for these patients seem to involve less invasive measures and less radiation by improving the current devices and by usage of machine-learning algorithms.

International audience ; Despite predictions of the paperless office, global demand for printing and writing paper remains strong, and paper appears to be here to stay for some time. Not only firms, but also governments, libraries, and archives are in possession of large collections of legacy documents that still must be sorted and scanned. In this study, terahertz-based techniques are demonstrated to address several routine tasks related to the automated paper handling of unsorted legacy documents. Specifically, we demonstrate terahertz-based counting of the number of sheets in unconsolidated paper stacks, as well as locating stapled documents buried in paper stacks.

International audience ; Despite predictions of the paperless office, global demand for printing and writing paper remains strong, and paper appears to be here to stay for some time. Not only firms, but also governments, libraries, and archives are in possession of large collections of legacy documents that still must be sorted and scanned. In this study, terahertz-based techniques are demonstrated to address several routine tasks related to the automated paper handling of unsorted legacy documents. Specifically, we demonstrate terahertz-based counting of the number of sheets in unconsolidated paper stacks, as well as locating stapled documents buried in paper stacks.

The ubiquitous presence of Galactic cirri in deep optical images represents a major obstacle to study the low surface brightness features of extragalactic sources. To address this issue, we have explored the optical properties of cirri using g, r, i, and z bands in the Sloan Digital Sky Survey (SDSS) Stripe82 region. Using state-of-the-art, custom made, image processing techniques, including the modeling and removal of the instrumental scattered light produced by the stars, we managed to isolate the optical diffuse emission by the cirri, allowing their photometric characterization. We find that their optical colors are driven by the dust column density: The cirri become redder as their 100 μm emission increases. Remarkably, the optical colors of the Galactic cirri differ significantly from those of extragalactic sources, with a characteristic bluer r-i color for a given g-r, allowing one to detect these by using a simple color relation. Our results show the high potential of deep multi-band optical photometry, on its own, identifying the presence of cirri at a higher spatial resolution than those provided by far-infrared observations. The combination of very deep data and multi-band photometry (as the one produced by LSST and Euclid) would make it possible to build dust maps of unprecedented quality. © 2020 ESO. ; The authors of this paper also acknowledge support from grant AYA2016-77 237-C3-1-P from the Spanish Ministry of Economy and Competitiveness (MINECO) and from IAC project P/300624, financed by the Ministry of Science, Innovation and Universities, through the State Budget and by the Canary Islands Department of Economy, Knowledge and Employment, through the Regional Budget of the Autonomous Community. We acknowledge support from the Fundación BBVA under its 2017 program of assistance to scientific research groups, for the project "Using machine-learning techniques to drag galaxies from the noise in deep imaging". JR acknowledge financial support from the grants AYA2015-65973-C3-1-R and RTI2018-096228-B-C31 (MINECO/FEDER, UE), as well as from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). I.T. acknowledges financial support from the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No 721463 to the SUNDIAL ITN network. We thank Timothy Brandt for sharing the spectrum of the diffuse galactic light with us. We thank Adolf Witt for interesting suggestions about our work. We thank Jorge Sánchez Almeida and David Valls-Gabaud for interesting discussions about the results. We thank Aaron Watkins for complementary analysis about the galactic dust colors and Juergen Fliri for his excellent work on the construction of the IAC Stripe82 Legacy Survey. We thank Lee Kelvin for sharing his code to compute beautiful color composed images. JR thanks Anastasia Khamatullina for interesting discussions. We thank the participants of the workshop "Exploring the Ultra-Low Surface Brightness Universe" hosted in the ISSI headquarters, Bern, Switzerland on January 2017, in which preliminary result were shown. We also thank the participants of the meeting "The low surface brightness Universe as seen by LSST" hosted in Sesto, Italy on January 2020 for interesting discussions ; Peer reviewed

Front Cover -- Annual Reports on NMR Spectroscopy -- Annual Reports on NMR Spectroscopy -- Copyright -- Contents -- CONTRIBUTORS -- PREFACE -- One - Solid-State NMR Studies of Molecular Crystals -- 1. INTRODUCTION -- 1.1 The Role of Molecular Crystals of Small Compounds in Development of Solid-State NMR Techniques -- 1.2 Very Fast MAS Solid-State NMR -- 1.3 2D and 3D Proton Solid-State NMR Techniques Under Very Fast Sample Spinning -- 1.4 Two-Dimensional Inverse Detected 1H-X Heteronuclear Techniques -- 1.5 Dynamic Nuclear Polarization Solid-State NMR -- 2. INORGANIC AND HYBRID INORGANIC-ORGANIC MOLECULAR CRYSTALS -- 3. MOLECULAR CRYSTALS OF SMALL ORGANIC COMPOUNDS, INCLUDING APIS -- 4. PHARMACEUTICAL COCRYSTALS -- 5. PHASE TRANSITIONS, MOLECULAR DISORDER, MOLECULAR DYNAMICS -- 5.1 De- and Rehydration Studies -- 5.2 Phase Transitions -- 5.3 Molecular Dynamics -- 5.4 Other Solid-State Processes Followed by Solid-State NMR -- 6. THEORETICAL METHODS SUPPORTING NMR ANALYSIS OF MOLECULAR CRYSTALS -- 6.1 Theoretical Approaches and Benchmarks -- 6.2 Application Examples -- 7. CONCLUSIONS -- ACKNOWLEDGEMENTS -- REFERENCES -- Two - Recent MRI Studies on Heterogeneous Catalysis -- 1. INTRODUCTION AND GENERAL INFORMATION -- 2. CONVENTIONAL MRI STUDIES OF CATALYTIC PROCESSES -- 2.1 Mapping of the Liquid Phase Distribution and Dynamics -- 2.2 Mapping Reactants and Products With Spectroscopic Resolution -- 2.3 Spatially Resolved Thermometry -- 3. MRI/MRS STUDIES WITH HYPERPOLARIZATION-BASED SIGNAL ENHANCEMENT -- 4. MRI STUDIES OF OPERATING MICROREACTORS -- 5. SUMMARY -- ACKNOWLEDGEMENTS -- REFERENCES -- Three - NMR Studies of Protic Ionic Liquids -- 1. INTRODUCTION -- 2. IONIC LIQUIDS -- 2.1 Protic Ionic Liquids -- 3. PROTON CHEMICAL SHIFTS AND PROTON TRANSFER -- 4. RELAXATION TIME EXPERIMENTS -- 4.1 Rotational Correlation times for Inert Solute Molecules

This handbook and ready reference covers materials science applications as well as microfluidic, biomedical and dental applications and the monitoring of physicochemical processes. It includes the latest in hardware, methodology and applications of spatially resolved magnetic resonance, such as portable imaging and single-sided spectroscopy. For materials scientists, spectroscopists, chemists, physicists, and medicinal chemists.