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The question "What do we really mean by technology?" has initiated a rich discussion among researchers and students, as well as consultants and lecturers, on a website during and after the summer of 2011. Complementary or alternative perspectives on topics like knowledge were discussed. Some discussants pointed at the meaning of knowledge and what is required of this 'matter' to understand technology. This article discusses factors that contribute to the difficulties in understanding technology, explaining by providing examples the movement from the concrete to abstractions when people try to design, classify, and understand technology in their environments. What has been ongoing during the last century is a process of understanding and controlling a radically changed world where terms like globalization and modernity express some of its key aspects. This process illustrates Beniger's (1986) claim that humans apply symbolic control systems which then control by their meaning. Each new technology increases the need for control and for improved control technology. The naming of artifacts/technologies is part of the control efforts. The use of metaphors is common and useful, but also adds to the abstraction.

THIS THESIS PRESENTS an empirical ethnographic study that has been conducted as fieldwork within army command organizations, leading to a qualitative analysis of data. The title of the thesis captures the contents of both command work and research, both domains being affected by new technologies during a period of drastic changes in the military institution. The overriding research question was why efforts to implement modern information technology are so slow, costly, and why the contribution from the output as regards higher control efficiency is so uncertain. Two cases will be described and analysed. One is a meeting and the other is the development of a computer artefact. Based on these two cases, the study suggests that social value and not only rational control efficiency defines what is applied, both in the development process and in practice. Knowledge and power, expertise and authority, represented by experts and formal leaders have to be brought together if the work is to be efficient. Both knowledge from research and information technology will be rejected, if considered irrelevant. I have called this applying a rationality of practice. From the case analysis it can be said that command work is not ordinary managerial work. Rather, it is a kind of design work, dynamic and hard to define and control. Command work is knowledge-intensive; it designs and produces symbols. Therefore it is very flexible and involves interpretation and negotiation of both its content and products. The most important symbol is the Army, which must be visible and credible, built from real components. Command work is pragmatic and opportunistic, conducted by experts in the modern military command structure who transform the operational environment, and control it through controlling actions. In that respect autonomy, a prerequisite to meet evolving events—frictions—and power become core issues, interchangeable goals and means for flexible social control, in cybernetic terms variety. Key concepts are social value, function and visibility. Actors must be visible in the command work, and make work visible. Consequently, when designing control tools, such as information systems, the design challenge is to reconcile dynamic and pragmatic demands for power, autonomy and control with demands for stability. Such an organization becomes a viable system, one that can survive, because there is no conflict between its mind and physical resources. In operational terms, this means having freedom of action. The prerequisite to achieve this is one perspective on knowledge and information and that information systems match the needs growing from within the work because work builds the organization.

MXenes constitute a family of two-dimensional transition metal carbides, carbonitrides and nitrides. Discovered in 2011, the number of MXenes has expanded significantly and more than 20 different MXenes have been synthesized, with many more predicted from theoretical calculations. MXenes constitute an exceptional family of materials based on their availability for elemental alloying and control of surface terminations, which enables synthesis of a range of structures and chemistries. Consequently, the MXenes exhibit an unparalleled potential for tuning of the materials properties for a wide range of applications. At present, MXenes have emerged with astonishing electronic, optical, plasmonic and thermoelectric properties. This has resulted in a global surge of research around a wide variety of applications, including but not limited to energy storage, carbon capture, electromagnetic interference shielding, reinforcement for composites, water filtering, sensors, and photo-, electro- and chemical catalysis etc. In this review, we present the available state of the art tailoring of the MXene properties owing to recent advances in structural ordering and tuning of surface terminations. ; Funding Agencies|Swedish Research CouncilSwedish Research Council [2016-04412, 2013-8020]; Knut and Alice Wallenbergs FoundationKnut & Alice Wallenberg Foundation [KAW 2015.0043]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; [RIF 14-0074]

Inherently and artificially layered materials are commonly investigated both for fundamental scientific purposes and for technological application. When a layered material is thinned or delaminated to its physical limits, a two-dimensional (2D) material is formed and exhibits novel properties compared to its bulk parent phase. The complex layered phases known as MAX phases (where M = early transition metal, A = A-group element, e.g. Al or Si, and X = C or N) are an exciting model system for materials design and the understanding of process-structure-property relationships. When the A layers are selectively etched from the MAX phases, a new type of 2D material is formed, named MXene to emphasize the relation to the MAX phases and the parallel with graphene. Since their discovery in 2011, MXenes have rapidly become established as a novel class of 2D materials with remarkable possibilities for composition variations and property tuning. This article gives a brief overview of MAX phases and MXene from a thin-film perspective, reviewing theory, characterization by electron microscopy, properties and how these are affected by the change in dimensionality, and outstanding challenges. ; Funding Agencies|European Research Council under the European Communitys Seventh Framework Programme (FP) ERC [335383, 258509]; knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; electron microscopy laboratory in Linkoping; Swedish Research Council (VR) [621-2012-4430, 6212012-4425, 642-2013-8020, 621-2012-4359, 622-2008405]; Swedish Foundation for Strategic Research (SSF) through the Synergy Grant FUNCASE; Future Research Leaders 5 program (PE); Swedish Government-Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; Research Infrastructure Fellow program (POAP)

We investigate, and quantify, changes in structure and surface terminations of epitaxial thin films of titanium carbide (Ti3C2) MXene, when treated by sodium hydroxide solution followed by vacuum annealing at 550 degrees C. Using X-ray photoelectron spectroscopy and scanning transmission electron microscopy, we show that NaOH treatment produce an increase in the c-lattice parameter together with an increase in the O terminations and a decrease in the F terminations. There is also an increase in the percentage of the binding energy of Ti-species in Ti 2p XPS region, which suggests an increase in the overall oxidation state of Ti. After subsequent annealing, the c-lattice parameter is slightly reduced, the overall oxidation state of Ti is decreased, and the F surface terminations are further diminished, leaving a surface with predominantly O as the surface terminating species. It is important to note that NaOH treatment facilitates removal of F at lower annealing temperatures than previously reported, which in turn is important for the range of attainable properties. ; Funding Agencies|Swedish Research Council [642-2013-8020, 2016-04412]; Knut and Alice Wallenberg (KAW) Foundation; Swedish Foundation for Strategic Research (SSF) [EM16-0004, RIF 14-0074]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]

In the present communication, the atomic structure and coordination of surface adsorbed species on Nb2C MXene is investigated over time. In particular, the influence of the Nb adatoms on the structural stability and oxidation behavior of the MXene is addressed. This investigation is based on plan-view geometry observations of single Nb2C MXene sheets by a combination of atomic-resolution scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS) and STEM image simulations. ; Funding agencies:The authors acknowledge the Swedish Research Council for funding under grants no. 2016- 04412 and 642-2013-8020, the Knut and Alice Wallenberg's Foundation for support of the electron microscopy laboratory in Linköping, a Fellowship grant and a project grant (KAW 2015.0043). The authors also acknowledge Swedish Foundation for Strategic Research (SSF) through the Research Infrastructure Fellow program no. RIF 14-0074. The authors finally acknowledge support from the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No 2009 00971

The spinodal decomposition and thermal stability of thin In0.72Al0.28N layers and In0.72Al0.28N/AlN superlattices with AlN(0001) templates on Al2O3(0001) substrates was investigated by in-situ heating up to 900 degrees C. The thermally activated structural and chemical evolution was investigated in both plan-view and cross-sectional geometries by scanning transmission electron microscopy in combination with valence electron energy loss spectroscopy. The plan-view observations demonstrate evidence for spinodal decomposition of metastable In0.72Al0.28N after heating at 600 degrees C for 1 h. During heating compositional modulations in the range of 2-3 nm-size domains are formed, which coarsen with applied thermal budgets. Cross-sectional observations reveal that spinodal decomposition begin at interfaces and column boundaries, indicating that the spinodal decomposition has a surface-directed component. ; Funding Agencies|Swedish Research Council (VR) [621-2012-4420, 621-2012-4359, 622-2008-405]; European Research Council (ERC); Swedish Foundation for Strategic research (SSF) through the Nano-N program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [SFO-Mat-LiU 2009-00971]; Knut and Alice Wallenberg Foundation

All atomically laminated MAB phases (M = transition metal, A = A-group element, and B = boron) exhibit orthorhombic or tetragonal symmetry, with the only exception being hexagonal Ti2InB2. Inspired by the recent discovery of chemically ordered hexagonal carbides, i-MAX phases, we perform an extensive first-principles study to explore chemical ordering upon metal alloying of M2AlB2 (M from groups 3 to 9) in orthorhombic and hexagonal symmetry. Fifteen stable novel phases with in-plane chemical ordering are identified, coined i-MAB, along with 16 disordered stable alloys. The predictions are verified through the powder synthesis of Mo4/3Y2/3 AlB2 and Mo4/3Sc2/3AlB2 of space group R (3) over barm (no. 166), displaying the characteristic in-plane chemical order of Mo and Y/Sc and Kagome ordering of the Al atoms, as evident from X-ray diffraction and electron microscopy. The discovery of i-MAB phases expands the elemental space of these borides with M = Sc, Y, Zr, Hf, and Nb, realizing an increased property tuning potential of these phases as well as their suggested potential twodimensional derivatives. ; Funding Agencies|Knut and Alice Wallenberg (KAW) FoundationKnut & Alice Wallenberg Foundation [KAW 2015.0043]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Swedish Research councilSwedish Research Council [2019-05047, 201904233, 2016-04412]; Swedish Foundation for Strategic Research (SSF) through the Research Infrastructure Fellow Program [RIF 14-0074]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

Recently, we presented a family of in-plane chemically ordered transition metal borides of the general formula (M-2/3M-1/3")(2)AlB2. Here, we investigate incorporation of magnetic rare earth (RE) elements into this structure by synthesis and analysis of Mo4/3RE2/3AlB2, where RE = Ho, Tb, and Er. The crystal structure is verified by X-ray diffraction and scanning transmission electron microscopy, while the composition is derived from energy dispersive X-ray analysis. Through magnetization measurements, we also show that Mo4/3Ho2/3AlB2 orders antiferromagnetically below 9 K. We suggest that (M-2/3M-1/3")(2)AlB2 could potentially be a versatile platform for new magnetic materials, in 3D as well as 2D. [GARPHICS] IMPACT STATEMENT This paper introduces magnetic elements to i-MAB phases family with a formula of Mo4/3RE2/3AlB2 (RE = Ho, Er, and Tb), which opens a venue for further exploration of chemically ordered magnetic materials. ; Funding Agencies|Knut and Alice Wallenberg (KAW) FoundationKnut & Alice Wallenberg Foundation [KAW 2020.0033]; Swedish Research councilSwedish Research CouncilEuropean Commission [2021-00471, 2019-04233]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

Mechanical treatments such as shredding or extrusion are applied to municipal solid wastes (MSW) to produce refuse-derived fuels (RDF). In this way, a waste fraction (mainly composed by food waste) is removed and the quality of the fuel is improved. In this research, simultaneous thermal analysis (STA) was used to investigate how different mechanical treatments applied to MSW influence the composition and combustion behaviour of fuel blends produced by combining MSW or RDF with wood in different ratios. Shredding and screening resulted in a more efficient mechanical treatment than extrusion to reduce the chlorine content in a fuel, which would improve its quality. This study revealed that when plastics and food waste are combined in the fuel matrix, the thermal decomposition of the fuels are accelerated. The combination of MSW or RDF and woody materials in a fuel blend has a positive impact on its decomposition. ; The authors would like to acknowledge Bio4Energy, a strategic research environment created by the Swedish government, for supporting this work.