Modulating the porosity of carbons for improved adsorption of hydrogen, carbon dioxide, and methane: A review

Porous carbons provide a potential low-cost route to a highly stable material for the adsorption of various gases. In particular, activated carbons (ACs) and zeolite templated carbons (ZTCs) show promise...

Bioprinting of Cartilage with Bioink Based on High-Concentration Collagen and Chondrocytes

The study was aimed at the applicability of a bioink based on 4% collagen and chondrocytes for de novo cartilage formation. Extrusion-based bioprinting was used for the biofabrication. The printing parameters were tuned to obtain stable material flow. In vivo data proved the ability of the tested bioink to form a cartilage within five to six weeks after the subcutaneous scaffold implantation. Certain areas of cartilage formation were detected as early as in one week. The resulting cartilage tissue had a distinctive structure with groups of isogenic cells as well as a high content of glycosaminoglycans and type II collagen.

“... Inconceivable, Unrealistic and Inhumane”. Internet Communication on the Flood Disaster in West Germany of July 2021 between Conspiracy Theories and Moralization— A Neopragmatic Explorative Study

The aim of this article is an explorative study of the debate on the flood in the western part of Germany in July 2021, based on the comments found below the coverage of a German public television channel (ZDF) published on YouTube. Based on the neopragmatic framing of the analysis by connecting morality and mass media according to Luhmann, as well as Dahrendorf’s conflict theory, four patterns of interpretation were identified which illustrate a high moralization of the conflict: conclusions drawn from the storm (e.g., of a political nature, references to COVID-19, etc.), far-reaching, predominantly negative interpretations that place the storm and its consequences in the context of other negatively interpreted aspects, as well as rational and empathetic interpretations regarding expressions of sympathy and offers of help, and, ultimately, interpretations that range from climate change and planning failures to various conspiracy-theoretical claims of responsibility for the flooding. All in all, a transformation from conflicts of interest and facts to conflicts of identity and values is taking place, revealing two utopias: the utopia in which man and nature are in harmonic unity, as well as the utopia of the satisfaction of individual (material) needs in a stable material-spatial and legal framework. Science has an instrumental application in both utopias.

Perhalogenation and Percyanation of Coronene for Characterization of the New Efficient Organic Semiconductors for Charge Transport

We have investigated the structures, electronic properties, hole and electron mobilities of perfluorinated, perchlorinated and percyanated coronene molecules, using the density functional theory (DFT) at the B3LYP-D3/6-311++G(d,p) and ωB97XD/6-311++G(d,p) levels and Markus-Hush charge transfer theory. The calculated geometric parameters for coronene and perchlorocoronene are in good agreement with the experimental data. Our theoretical investigations have shown B3LYP-D3 functional is suitable to well define vibrational assignments for studied molecules. We have shown that the per-halogenation and per-cyanation of coronene increases the adiabatic electron affinities (AEAs) and reduces the LUMO levels and the hole mobilities thus indicating an ambipolar behavior and air-stable material. We have shown that the percyanation of coronene is a promising pathway for the design of new materials useful in optoelectronics.

Two dimensional V2O3 and its experimental feasibility as robust room-temperature magnetic Chern insulator

The possibility of dissipationless chiral edge states without the need of an external magnetic field in the quantum anomalous Hall effect (QAHE) offers a great potential in electronic/spintronic applications. The biggest hurdle for the realization of a room-temperature magnetic Chern insulator is to find a structurally stable material with a sufficiently large energy gap and Curie temperature that can be easily implemented in electronic devices. This work based on first-principle methods shows that a single atomic layer of V2O3 with honeycomb–kagome (HK) lattice is structurally stable with a spin-polarized Dirac cone which gives rise to a room-temperature QAHE by the existence of an atomic on-site spin–orbit coupling (SOC). Moreover, by a strain and substrate study, it was found that the quantum anomalous Hall system is robust against small deformations and can be supported by a graphene substrate.

Farming Resilience: From Maintaining States towards Shaping Transformative Change Processes

Resilience is a concept that focuses on change: it includes the ability of a system to maintain its current state despite disturbances, its ability to adapt, and to transform. While resilience covers both stability and change, conceptual developments and empirical studies have put more emphasis on identifying what enables a farm to cope with the impact of a shock, such as a shift in markets or an extreme weather event, while remaining essentially unchanged. Much less emphasis has been put on what enables a farm to shape change, especially transformative change. I argue that this bias is partly due to the ecological roots of the concept, and partly to the use of conventional methods and their underlying substantialist worldview. A process-relational approach might be better suited to capture change. This approach shifts the conceptualization of a ‘farm’ as a stable material structure, to ‘farming’ as an open process of becoming, composed of heterogenous relations that are continuously made and remade. By exploring the differences between these two approaches to farm/farming resilience, I show how a process-relational approach displaces the presumption of structural determination and thus allows to highlight the ever-present openings for change.

On Tailoring Co-Precipitation Synthesis to Maximize Production Yield of Nanocrystalline Wurtzite ZnS

Pyroelectric materials can harvest energy from naturally occurring ambient temperature changes, as well as from artificial temperature changes, notably from industrial activity. Wurtzite- based materials have the advantage of being cheap, non-toxic, and offering excellent opto-electrical properties. Due to their non-centrosymmetric nature, all wurtzite crystals have both piezoelectric and pyroelectric properties. Nanocrystalline wurtzite ZnS, being a room temperature stable material, by contrast to its bulk counterpart, is interesting due to its still not well-explored potential in piezoelectric and pyroelectric energy harvesting. An easy synthesis method—a co-precipitation technique—was selected and successfully tailored for nanocrystalline wurtzite ZnS production. ZnS nanopowder with nanoparticles of 3 to 5 nm in size was synthesized in ethyl glycol under medium temperature conditions using ZnCl2 and thiourea as the sources of Zn and S, respectively. The purified and dried ZnS nanopowder was characterized by conventional methods (XRD, SEM, TEM, TG and FTIR). Finally, a constructed in-house pilot plant that is able to produce substantial amounts of wurtzite ZnS nanopowder in an environmentally friendly and cost-effective way is introduced and described.

The colour stability of crystallized acetyl resin material in comparison to other restorative materials. An in-vitro study

Aim To investigate the colour stability of Crystalized Acetyl Resin, in comparison to three other aesthetic restorative materials, when immersed in different staining aqueous solutions. Materials and methods Fifteen disc-shaped specimens each, of the four materials tested, were immersed in either DW or 4 staining solutions. CIE L*a*b* values were recorded using a digital spectrophotometer on a weekly basis for 4 weeks. Data were compared using three- way/two-way ANOVA along with auto-regressive model. Results Two-way Anova indicates that there is a significant colour change in all materials over time when immersed in the different staining solutions. Auto-regressive model showed that the colour change in each successive week was statistically significant (P < 0.001). Conclusion The most staining solution affecting the materials during this study was black coffee. Within the limitation of this study, Acetyl Resin was the most colour stable material among the other materials.

Synthesis and Application of Nanolayered and Nanoporous Materials

Nanoscale materials are currently an attractive research subject because their properties are in contrast to their macroscopic counterparts. An inert material, such as bulk platinum metal for example, is known to exhibit a catalytic properties when its size is reduced into nanoscale. A stable material can become flammable or combustible, such as aluminum, and isolator material can become a conductor. Many attractive quantum phenomena also arise from reducing a material size into nanoscale dimensions. This review article discusses the concept, synthesis, and characterization of organic and inorganic nanolayered and nanoporous materials; and their application to catalysis and adsorption processes. Past achievements and future perspectives in the field of nanomaterial researches will be discussed as well. Furthermore, in the era of green chemistry, nanomaterials with all their derivatives are also required to have sustainable characteristics, such as biodegradable and renewable; which emphasizes that the development of nanomaterials in the framework of green chemistry should always be a priority. Through the synthesis of novel and functional nanomaterials using natural and local-based materials around us that are environmentally friendly and relatively easy to be obtained, our goal toward the inheritance of a greener world for the future generations is not an impossible dream.