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The literature on populist attitudes frequently makes one of two assumptions: populist attitudes are either stable or unstable. However, few studies have examined these diverging assumptions empirically. We use panel data collected over six panel waves between 2017 and 2021 in Germany to assess the stability of populist attitudes. Integrating inter-individual stability (variable-centred) and intra-individual stability (individual trajectories), we find that populist attitudes are neither fully stable (trait) nor fully flexible (state). For example, some respondents constantly changed their view on populism while the attitudes in one out of three individuals remained stable. We also explore empirical consequences and find that populist attitudes are more closely linked to vote choice when they are stable. Accordingly, we argue for a more nuanced understanding of the dynamics of populist attitudes, both at the variable and individual levels, where these attitudes are stable and consequential for only a subset of individuals. [ABSTRACT FROM AUTHOR]

Although many challenges of the 21st century need solutions which are directly connected with the development of new technologies, the preferences of prospective students in Germany are often far from mathematics, physics and chemistry. Moreover, the acceptance and recognition of new achievements in these disciplines are quite low in society, even if these achievements are the basis for the development of new technologies that positively affect daily life. As a part of a campaign intended to increase the number of students in the fields of materials science and materials technology (and related fields), the authors created an escape room focused on materials science and crystallography, which illustrates the approaches used by materials scientists and the beauty of crystallography. The fundamental features of the escape room, which are presented in this contribution, are its variability and the ability to inspire participants who have different backgrounds in physics, chemistry and/or materials science. By varying the level of difficulty and the game play duration, the escape room structure makes it possible to appeal to a broad audience, offer an authentic escape room experience and impart lasting knowledge through reflection after completion. The authors' experiences with the escape room and the feedback from the attendees are summarized at the end of the contribution. [ABSTRACT FROM AUTHOR]

We expand on ongoing debates about the role of economic losses and benefits for a clean energy transition. Rather than focusing on the potential economic benefits of alternative industries and energy sources, we highlight the role of economic optimism people display towards the fossil fuel industry. We argue that people's confidence in the fossil fuel industry to remain an important economic driver in the future can undermine support for climate policies because people do not perceive a need to turn to alternative industries for economic prosperity. Instead, they continue to support the status-quo. We test our argument using survey level data collected in the spring of 2019 in the Canadian province of Alberta, an ideal case due to the province's economic dependence on the fossil fuel industry. The results support our argument, highlighting the need for policymakers to develop communication strategies on future economic benefits of energy transition. [ABSTRACT FROM AUTHOR]

The generation and long-haul transmission of highly entangled photon pairs is a cornerstone of emerging photonic quantum technologies with key applications such as quantum key distribution and distributed quantum computing. However, a natural limit for the maximum transmission distance is inevitably set by attenuation in the medium. A network of quantum repeaters containing multiple sources of entangled photons would allow overcoming this limit. For this purpose, the requirements on the source's brightness and the photon pairs' degree of entanglement and indistinguishability are stringent. Despite the impressive progress made so far, a definitive scalable photon source fulfilling such requirements is still being sought after. Semiconductor quantum dots excel in this context as sub-Poissonian sources of polarization entangled photon pairs. In this work, we present the state-of-the-art set by GaAs based quantum dots and use them as a benchmark to discuss the challenges toward the realization of practical quantum networks. [ABSTRACT FROM AUTHOR]

Multidimensional concepts are non-compensatory when higher values on one component cannot offset lower values on another. Thinking of the components of a multidimensional phenomenon as non-compensatory rather than substitutable can have wide-ranging implications, both conceptually and empirically. To demonstrate this point, we focus on populist attitudes that feature prominently in contemporary debates about liberal democracy. Given similar established public opinion constructs, the conceptual value of populist attitudes hinges on its unique specification as an attitudinal syndrome, which is characterized by the concurrent presence of its non-compensatory concept subdimensions. Yet this concept attribute is rarely considered in existing empirical research. We propose operationalization strategies that seek to take the distinct properties of non-compensatory multidimensional concepts seriously. Evidence on five populism scales in 12 countries reveals the presence and consequences of measurement-concept inconsistencies. Importantly, in some cases, using conceptually sound operationalization strategies upsets previous findings on the substantive role of populist attitudes. [ABSTRACT FROM AUTHOR]

Recent research in the populism literature has devoted considerable efforts to the conceptualisation and examination of populism on the individual level, that is, populist attitudes. Despite rapid progress in the field, questions of adequate measurement and empirical evaluation of measures of populist attitudes remain scarce. Seeking to remedy these shortcomings, we apply a cross-national measurement model, using item response theory, to six established and two new populist indicators. Drawing on a cross-national survey (nine European countries, n = 18,368), we engage in a four-folded analysis. First, we examine the commonly used 6-item populism scale. Second, we expand the measurement with two novel items. Third, we use the improved 8-item populism scale to further refine equally comprehensive but more concise and parsimonious populist measurements. Finally, we externally validate these sub-scales and find that some of the proposed sub-scales outperform the initial 6- and 8-item scales. We conclude that existing measures of populism capture moderate populist attitudes, but face difficulties measuring more extreme levels, while the individual information of some of the populist items remains limited. Altogether, this provides several interesting routes for future research, both within and between countries. [ABSTRACT FROM AUTHOR]

This article investigates how Canadian voters react to a perceived lack of quality provided by their most preferred parties and how the anticipated election outcome conditions the reactions. The central argument is that a lack of quality motivates voters to signal their discontent by voting insincerely—that is, they cast a protest vote. The effect is expected to be moderated by the anticipated constituency result. The arguments are tested with two-wave panel survey data from the 2015 Canadian federal election, collected by the Making Electoral Democracy Work (MEDW) project. The results support the central argument but remain inconclusive about the expected moderating effects. [ABSTRACT FROM AUTHOR]

Today, populism has gradually become one of the most talked about, most studied phenomena, both within and beyond academia. Most studies of populism focus on its conceptualisation, operationalisation, measurement or its outcomes. However, adding to the growing empirical analysis of populism, we propose to study populism as a regional-level phenomenon and explain regional patterns of variation in the populist demand. To do so, we develop a series of theoretical arguments from, which we subsequently test empirically. Specifically, we argue that higher levels of regional populism demand are associated with (i) economic hardship, (ii) strong institutional autonomy, (iii) strong territorial identity, and (iv) greater distance to elites. We construct a populist index for 143 regions across nine countries and combine this with a unique and rich regional database. While we find that populism holds distinct regional patterns and there is support for classic predictors like economic hardship, we are also able to provide some unique insights into the regional foundations of populism, most notably the predictive power of regional identity and the distance to national elites. [ABSTRACT FROM AUTHOR]

Two different preparation routes were applied to process WC-MgO composites with varying MgO contents (4.1 wt.% and 5.9 wt.% MgO). WC-MgO powder mixtures were synthesized by a milling process at 600 rpm for 6 h of partially oxidized WC (WC + WO 3 ), Mg 3 N 2 and C. Alternatively, WC and MgO as initial powders were used. For consolidation of the powder mixtures the field-assisted sintering technology (FAST) was used. X-ray diffraction shows that samples out of different powder mixtures and sintered between 1600 °C and 1750 °C exhibited WC, MgO and the W 2 C phase independent of the preparation route of the powder mixtures. A higher density and better mechanical properties (hardness and indentation fracture toughness) of WC-MgO were achieved of pure WC and MgO as initial powders were consolidated by FAST. It was found that a lower MgO content results in higher hardness values and in a slightly decreased indentation fracture toughness. [ABSTRACT FROM AUTHOR]

This article examines the influence of populism on democratic quality in Latin America. It draws on findings of qualitative work on this question as well as a theoretical framework by Cas Mudde and Cristóbal Rovira Kaltwasser to test whether the assumptions and results of both are applicable in a comparative study. It is expected that populist actors have a negative impact on democratic quality when they are in government, but that they positively influence democratic quality when they are in opposition, where they can function as a corrective. Further, it is expected that these effects vary depending on the level of consolidation. A linear mixed-effects model and data from eighteen Latin American countries in the period 1995–2009 was used to evaluate the hypotheses. Generally, it was found that populist actors in opposition have a large positive influence on democratic quality and that populist actors in government have a negative influence. [ABSTRACT FROM AUTHOR]

The hot corrosion behavior of plasma transferred arc (PTA) welded René 41 in NaCl, NaVO3, Na2SO4, and a salt mixture of 87.5 wt% Na2SO4 + 5 wt% NaCl + 7.5 wt% NaVO3 was investigated at 600°C. The single‐salt experiments were carried out to identify specific corrosion characteristics and to provide insights into and, thus, an understanding of the corresponding corrosion processes. NaVO3 and NaCl showed strong corrosive effects, while Na2SO4 proved less corrosive. Long‐term experiments were carried out to simulate real machine operating conditions. After cyclic studies with repeated changes in temperature, the deep and local corrosive attack became apparent, which is characteristic for low‐temperature hot corrosion. [ABSTRACT FROM AUTHOR]

This paper presents the results of diagnostic examinations conducted on the coils of super-heaters made of 10CrMo9-10 steel that were operated in industrial conditions at 480°C for 130 thousand hours. The tube was exposed in a coal-fired boiler. The chemical and phase composition of the oxide/deposit layers formed on both sides of the tube walls (outside - flue-gas side and inside - steam side) and their sequence was examined using optical microscopy, scanning electron microscopy with electron backscatter diffraction and energy-dispersive X-ray spectroscopy, and X-ray diffraction. The changes in the mechanical properties caused by corrosion and aging processes were concluded from the hardness measurements. In addition, the nature of cracks in the oxide layers caused by pressing a Vickers indenter was determined. The results of these examinations have shown a high degradation of steel on the flue-gas inflow side and identified the main corrosion products and mechanisms. Abstract. This paper presents the results of diagnostic examinations conducted on the coils of super-heaters made of 10CrMo9-10 steel that were operated in industrial conditions at 480°C for 130 thousand hours. The tube was exposed in a coal-fired boiler. The chemical and phase composition of the oxide/deposit layers formed on both sides of the tube walls (outside - flue-gas side and inside - steam side) and their sequence was examined using optical microscopy, scanning electron microscopy with electron backscatter diffraction and energy-dispersive Xray spectroscopy, and X-ray diffraction. The changes in the mechanical properties caused by corrosion and aging processes were concluded from the hardness measurements. In addition, the nature of cracks in the oxide layers caused by pressing a Vickers indenter was determined. The results of these examinations have shown a high degradation of steel on the flue-gas inflow side and identified the main corrosion products and mechanisms. [ABSTRACT FROM AUTHOR]

Photonic structures capable of enhancing the light‐outcoupling efficiency of embedded epitaxial quantum dots (QDs) in a broad spectral range are attractive for the realization of bright sources of single photons and entangled photon pairs. In this work, a planar‐multilayer antenna is experimentally demonstrated for GaAs QDs embedded in AlGaAs membranes. The antenna consists of a metal (Au or Ag) reflector and a semi‐transparent metal (Ag) director, with a thin oxide layer (hafnium dioxide (HfO2) or aluminium oxide (Al2O3)) between metal and semiconductor layers. Simulations using the 3D finite‐difference time‐domain (FDTD) method indicate a maximal efficiency of 43% (for collection optics with a numerical aperture (NA) of 0.85), a wavelength‐dependent Purcell factor ranging from ≈0.7 to ≈1.45, strong directional emission characteristics, as well as a broad bandwidth of ≈30 nm. In the experiment, we find a Purcell factor compatible with the simulation results, a maximum collection efficiency as high as ≈19% and an ultralow multiphoton emission probability of 0.006 ± 0.005. The planar geometry, its compatibility with post‐growth tuning methods, facile fabrication, broad spectral bandwidth, and achieved performance make the presented structure competitive for solid‐state sources of quantum light. [ABSTRACT FROM AUTHOR]

Surface-directed and preferentially oriented assemblies of nanomaterials can enable enhanced applications in e.g. catalysis or sensing. Coordination polymers, which can be even conducting, could be suitable materials for this purpose because of their facile surface anchoring. Hence, we coassembled rhodium paddle-wheel building blocks with bi- or trifunctional linkers in dip coatings that were produced by layer-by-layer approach on silicon wafers functionalized by thin nanocrystalline gold surfaces. These gold surfaces were decorated with a self-assembled monolayer (SAM) for coordination and binding to the Rh-units. As linkers, pyrazine, triazine and melamine were used, leading to rectangularly-shaped, hexagonally-shaped or needle-like crystals, respectively. The coordination polymers were produced by repeated dipping into the linker and paddle-wheel solution, each followed by a cleaning step. The crystals growth was followed by atomic force microscopy (AFM) grazing incidence small-angle X-ray scattering (GISAXS) and grazing incidence wide-angle X-ray scattering (GIWAXS). AFM and GISAXS revealed the shape and size of the crystals. GIWAXS disclosed their preferred orientation. It turned out that the automated dipping procedure does not lead to a strong alignment of crystallites along the dipping direction for the pyrazine-based deposits. However, these crystals are preferentially oriented with respect to the substrate normal direction. The crystallographic direction and the degree of the alignment depend on the number of deposition cycles. In the early phases of the deposition process, predominantly "lying" crystals were detected. With increasing number of the deposition cycles, the fraction of "standing" crystals became dominant. These crystals are oriented with their {010} directions perpendicular to the surface of the substrate. Still, "lying" and some tilted crystals were detected additionally. The study gives a deeper structural understanding of crystallite assemblies and suggests an evolvement of more anisotropic orientations of the crystallites with increasing deposition cycles (leading to the prevalence of crystals having the preferred {010} orientation with respect to the surface normal direction). [ABSTRACT FROM AUTHOR]

The article discusses the research on designing a quantum teleportation protocol using solid-state quantum emitters. According to the author entangled photon pairs generated on-demand by the quantum emitter were used to develop the protocol. Topics include fabrication of gallium quantum dot system, light sources of photons, and measurement of photon emission rate.

The presented work sets out to investigate the influence of aluminium on the hydrogenation of vanadium by first studying the hydrogenation properties of the V–H system in detail followed by the study of the V–Al–H system. Aluminium was found to have a stabilising effect on vanadium hydride phases. Presumably by functioning as an oxygen getter, aluminium lowers equilibrium pressures and increases hydrogen capacities in respect to the V/H ratio compared to the V–H system. Attempts of the synthesis of the hypothetical V(AlH4)x by metathesis and direct hydrogenation were not successful, suggesting its instability below room temperature at ambient pressure as well as up to 180 bar of hydrogen pressure in the temperature range of 30 to 100 °C. [ABSTRACT FROM AUTHOR]

Austenitic steels are known to exhibit a low hydrogen diffusion coefficient and hence a good resistance to hydrogen embrittlement. Therefore, it is an experimental challenge to investigate their hydrogen diffusion properties. In this study, the electrochemical permeation technique is used to determine the hydrogen diffusion coefficients in different pre-deformed states (φ = 0, 0.32, 0.39, 0.49) of the high-alloy austenitic TRIP steel X3CrMnNiMoN17-8-4 in a temperature range of 323 K–353 K. In combination with microstructural analysis, a correlation between phase transformation from γ-austenite to α′-martensite and dislocation density is shown. As a result of the lattice transformation from fcc to bcc, the diffusion rate of hydrogen is significantly increased (D app, φ = 0 = 3.6 × 10−12 cm2 s−1, D app, φ = 0.32 = 1.6 × 10−11 cm2 s−1at 323 K). With higher degrees of deformation, the dislocation density also increased in the martensite islands, resulting in a degressive growth of the diffusion coefficient (D app, φ = 0.39 = 5.3 × 10−11 cm2 s−1, D app, φ = 0.49 = 1.1 × 10−10 cm2 s−1at 323 K). Moreover, detailed calculations are performed to describe the way of hydrogen trapping and to give a possible mechanism of diffusion. [Display omitted] • Diffusion coefficients of H in austenitic steel (e.g. D 323 K = 3.6 × 10−12 cm2 s−1). • Accelerated hydrogen diffusion due to strain-induced α′-martensite formation. • Amount of trapped hydrogen strongly decreases with increasing temperature. • Solubility of hydrogen significantly decreases with increasing α′-martensite. [ABSTRACT FROM AUTHOR]

This study addresses the potential of active screen plasma nitrocarburising (ASPNC) treatment applying a carbon active screen for short-time low-temperature diffusion treatment of AISI 420 martensitic stainless steel in terms of varying the bias plasma power directly at the steel surface. Without the application of a bias plasma the nitrocarburising effect was reduced due to cementite formation near the surface. The application of bias plasma in ASPNC processes resulted in the formation of expanded α′-martensite and ε-carbonitride and inhibited cementite formation. Thickness and phase composition of nitrocarburised layers produced by means of ASPNC were comparable to those that can be generated by conventional plasma nitrocarburising (CPNC), but with reduced plasma impact on the steel surfaces implying considerably lower thermal stress. Surfaces treated by ASPNC with bias plasma showed a tendency towards improved pitting resistance in a 3.5 wt% sodium chloride electrolyte compared to those generated by CPNC. • Bias plasma is essential for nitrocarburising of martensitic stainless steel. • ASPNC with reduced bias plasma increases surface hardness comparable to CPNC. • ASPNC with reduced bias plasma favours ε-Fe 3 N and inhibits cementite formation. • ASPNC tends to improve pitting corrosion resistance compared to CPNC. [ABSTRACT FROM AUTHOR]

In spite of existing experimental evidence for phase transitions of the γ′-Fe 4 N phase at high-pressure/high-temperature conditions, some controversy about its pressure/temperature stability range prevails in recent literature. In the present work, a thermodynamic database allowing the calculation of phase equilibria, involving the solid phases in the Fe-rich part of the Fe–N system at high-pressure conditions, is presented. For this, an existing database, which describes the atmospheric-pressure phase equilibria of Fe–N phases up to N contents of 33 at% N, has been extended by equation of state parameters describing the molar volume as a function of temperature, pressure and composition. For the pure Fe side, equation-of-state (EOS) parameters from the literature have been used. Corresponding EOS parameters for the Fe–N phases have been derived from literature data as well as own experimental data on the compression and thermal expansion behaviour and volume-composition data. On basis of the so-obtained database, phase equilibria up to a pressure of 13 GPa have been calculated. The agreement of calculated phase equilibria and own previously published experimental results is reasonable. In the presently calculated P – T projection of the univariant equilibria in the system, the phase region of the γ′ phase terminates in a quadruple point at 5.0 GPa and 713 K. This further substantiates the conclusion drawn from own previous experimental results, according to which the γ′ phase region terminates at 5.0 − 0.5 + 1.1 GPa and 648 − 25 + 56 K. • thermodynamic database for 1 atm extended by EOS parameters. • allows prediction of phase equilibria up to at least 13 GPa. • reasonable agreement with literature data. • phase region of γ′-Fe 4 N terminates at 5 GPa and 713 K. [ABSTRACT FROM AUTHOR]

Hematite (α-Fe2O3) catalysts prepared using the precipitation methods was found to be highly effective, and therefore, it was studied with methane (CH4), showing an excellent stable performance below 500 °C. This study investigates hematite nanoparticles (NPs) obtained by precipitation in water from the precursor of ferric chloride hexahydrate using precipitating agents NaOH or NH4OH at maintained pH 11 and calcined up to 500 °C for the catalytic oxidation of low concentrations of CH4 (5% by volume in air) at 500 °C to compare their structural state in a CH4 reducing environment. The conversion (%) of CH4 values decreasing with time was discussed according to the course of different transformation of goethite and hydrohematites NPs precursors to magnetite and the structural state of the calcined hydrohematites. The phase composition, the size and morphology of nanocrystallites, thermal transformation of precipitates and the specific surface area of the NPs were characterized in detail by X-ray powder diffraction, transmission electron microscopy, infrared spectroscopy, thermal TG/DTA analysis and nitrogen physisorption measurements. The results support the finding that after goethite dehydration, transformation to hydrohematite due to structurally incorporated water and vacancies is different from hydrohematite α-Fe2O3. The surface area SBET of Fe2O3_NH-70 precipitate composed of protohematite was larger by about 53 m2/g in comparison with Fe2O3_Na-70 precipitate composed of goethite. The oxidation of methane was positively influenced by the hydrohematites of the smaller particle size and the largest lattice volume containing structurally incorporated water and vacancies. [ABSTRACT FROM AUTHOR]

Abstract: A sintering route to fully-dense near-nanocrystalline WC–12Co without grain growth inhibitors was developed. The influence of sintering parameters on the densification, microstructure, and mechanical properties of the material compacted by Field Assisted Sintering Technology (FAST) was investigated. High and low-effect sintering parameters were identified, and a process to consolidate nearly fully-dense cemented carbide samples with mean grain sizes of about 200nm was elaborated. The parameters of the sintering process were adapted in order to maximise densification on the one hand and, on the other hand, to avoid growth of the WC grains during the sintering process. Furthermore, the reproducibility of the sintering process with respect to densification was tested. Microscopic examination of the sintered samples showed a minimisation of inhomogeneity combined with maximisation of the relative density, while the impact of the sintering parameters on the microstructural parameters was found to be insignificant. X-ray diffraction (XRD) was applied to determine the phase composition and crystallite size of the sintered WC. [Copyright &y& Elsevier]

Abstract: In this study, a conventional nano-grained tungsten carbide (WC) powder was mixed with 12wt.% of a submicron cobalt (Co) powder in a ball mill for varying milling time periods, producing a homogeneous powder mixture which can be used to sinter near-nanocrystalline cemented carbides using short-duration sintering processes. Parameters of the wet milling process were adapted in order to maximise the mixing effect on the one hand, and to avoid particle growth during the milling process on the other. Surface analysis and microscopic examination of the milled powders showed a milling-time-dependent evolution of particle size and surface roughness. X-ray diffraction (XRD) investigation indicated a decrease of the crystallite size of WC in combination with an increase in defect density, as well as a strong increase in stacking faults in the Co. The main action of the milling mechanism is the fracturing of the WC particles. Co is distributed consistently around the WC particles. The preparation method used is a useful technique to prepare homogeneous powder mixtures of WC–Co with particle sizes below 200nm on a laboratory scale. [Copyright &y& Elsevier]

Marine sponges were among the first multicellular organisms on our planet and have survived to this day thanks to their unique mechanisms of chemical defense and the specific design of their skeletons, which have been optimized over millions of years of evolution to effectively inhabit the aquatic environment. In this work, we carried out studies to elucidate the nature and nanostructural organization of three-dimensional skeletal microfibers of the giant marine demosponge Ianthella basta, the body of which is a micro-reticular, durable structure that determines the ideal filtration function of this organism. For the first time, using the battery of analytical tools including three-dimensional micro—X-ray Fluorescence (3D-µXRF), X-ray diffraction (XRD), infra-red (FTIR), Raman and Near Edge X-ray Fine Structure (NEXAFS) spectroscopy, we have shown that biomineral calcite is responsible for nano-tuning the skeletal fibers of this sponge species. This is the first report on the presence of a calcitic mineral phase in representatives of verongiid sponges which belong to the class Demospongiae. Our experimental data suggest a possible role for structural amino polysaccharide chitin as a template for calcification. Our study suggests further experiments to elucidate both the origin of calcium carbonate inside the skeleton of this sponge and the mechanisms of biomineralization in the surface layers of chitin microfibers saturated with bromotyrosines, which have effective antimicrobial properties and are responsible for the chemical defense of this organism. The discovery of the calcified phase in the chitinous template of I. basta skeleton is expected to broaden the knowledge in biomineralization science where the calcium carbonate is regarded as a valuable material for applications in biomedicine, environmental science, and even in civil engineering. [ABSTRACT FROM AUTHOR]

This Perspective presents an overview on the epitaxial growth and optical properties of GaAs quantum dots obtained with the droplet etching method as high-quality sources of quantum light. We illustrate recent achievements regarding the generation of single photons and polarization entangled photon pairs and the use of these sources in applications of central importance in quantum communication such as entanglement swapping and quantum key distribution. [ABSTRACT FROM AUTHOR]

Broadband optical cavities, dielectric planar antennas, GaAs quantum dots, single photon sources Keywords: broadband optical cavities; dielectric planar antennas; GaAs quantum dots; single photon sources EN broadband optical cavities dielectric planar antennas GaAs quantum dots single photon sources 1 1 1 04/08/21 20210406 NES 210406 A planar metal-oxide-semiconductor structure, capable of beaming the photons emitted by epitaxial quantum dots into free space, has been designed and implemented by Huying Huang, Santanu Manna, Armando Rastelli and co-workers (see article number 2001490). [Extracted from the article]

By time-of-flight (TOF) neutron diffraction experiments, the influence of segregation-induced microstructure bands of austenite (γ) and martensite (α′) phases on the partitioning of stress and strain between these phases was investigated. Initially, tensile specimens of a Co-added stainless steel were heat treated by quenching and partitioning (Q&P) processing. Tensile specimens were subsequently loaded at 350 °C parallel to the length of the bands within the apparent elastic limit of the phase mixture. Lattice parameters in both axial and transverse directions were simultaneously measured for both phases. The observation of a lattice expansion for the γ phase in the transverse direction indicated a constraint on the free transverse straining of γ arising from the banded microstructure. The lateral contraction of α′ imposed an interphase tensile microstress in the transverse direction of the γ phase. The multiaxial stress state developed in the γ phase resulted in a large deviation from the level of plastic strain expected for uniaxial loading of single phase γ. Since segregation-induced banded microstructures commonly occur in many engineering alloys, the analysis of stress and strain partitioning with the present Q&P steel can be used to interpret the observations made for further engineering alloys with two-phase microstructures. [ABSTRACT FROM AUTHOR]

Separation of size and strain effects on diffraction line profiles has been studied in a round robin involving laboratory instruments and synchrotron radiation beamlines operating with different radiation, optics, detectors and experimental configurations. The studied sample, an extensively ball milled iron alloy powder, provides an ideal test case, as domain size broadening and strain broadening are of comparable size. The high energy available at some synchrotron radiation beamlines provides the best conditions for an accurate analysis of the line profiles, as the size–strain separation clearly benefits from a large number of Bragg peaks in the pattern; high counts, reliable intensity values in low‐absorption conditions, smooth background and data collection at different temperatures also support the possibility to include diffuse scattering in the analysis, for the most reliable assessment of the line broadening effect. However, results of the round robin show that good quality information on domain size distribution and microstrain can also be obtained using standard laboratory equipment, even when patterns include relatively few Bragg peaks, provided that the data are of good quality in terms of high counts and low and smooth background. [ABSTRACT FROM AUTHOR]

Photonic quantum technologies are on the verge of finding applications in everyday life with quantum cryptography and quantum simulators on the horizon. Extensive research has been carried out to identify suitable quantum emitters and single epitaxial quantum dots have emerged as near-optimal sources of bright, on-demand, highly indistinguishable single photons and entangled photon-pairs. In order to build up quantum networks, it is essential to interface remote quantum emitters. However, this is still an outstanding challenge, as the quantum states of dissimilar "artificial atoms" have to be prepared on-demand with high fidelity and the generated photons have to be made indistinguishable in all possible degrees of freedom. Here, we overcome this major obstacle and show an unprecedented two-photon interference (visibility of 51 ± 5%) from remote strain-tunable GaAs quantum dots emitting on-demand photon-pairs. We achieve this result by exploiting for the first time the full potential of a novel phonon-assisted two-photon excitation scheme, which allows for the generation of highly indistinguishable (visibility of 71 ± 9%) entangled photon-pairs (fidelity of 90 ± 2%), enables push-button biexciton state preparation (fidelity of 80 ± 2%) and outperforms conventional resonant two-photon excitation schemes in terms of robustness against environmental decoherence. Our results mark an important milestone for the practical realization of quantum repeaters and complex multiphoton entanglement experiments involving dissimilar artificial atoms. [ABSTRACT FROM AUTHOR]

TiN–AlN powder mixtures of commercial TiN and AlN powders with variable AlN contents (15 vol% and 25 vol%) were ball-milled for 3 and 6 h before subsequent consolidation by spark plasma sintering (SPS). The high-energy ball milling process induced mechanical alloying of the TiN with AlN, which was associated with the incorporation of AlN into the crystal structure of the TiN. In addition to the primary phases, which were the face centered cubic TiN and hexagonal wurtzitic AlN, the sintered samples contained crystalline γ-AlON after sintering. This study investigated the effect of the powder milling time, the sintering temperature and the AlN volume fraction on the hardness, fracture toughness and compressive strength of the TiN–AlN composites. It was found that the sintering temperature (1600 °C or 1700 °C) had only a marginal influence on the mechanical properties. An increase in hardness and a slightly enhanced average fracture toughness were caused by the increase of the AlN content from 15 vol% to 25 vol%. An influence of the AlN volume fraction on the compressive strength could not be determined. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ratio of Fe 2 O 3 and CeO 2 is strongly affecting hydrogen photogeneration. • Determination of Fermi levels is the key to obtain idea of charge transfer. • Efficient Type I heterojunction was confirmed by work function measurements. • The most efficient sample Fe 8 Ce 2 possessed optimal particle distribution. • Photocatalyst anchored on vermiculite is promising due to an easier separation. The study is focused on the photocatalytic ability of nanocrystalline oxides Fe 2 O 3 and CeO 2 (marked as Fe and Ce) and their 8:2, 5:5 and 2:8 M ratio mixtures (marked as Fe 8 Ce 2 , Fe 5 Ce 5 and Fe 2 Ce 8) for the hydrogen production via water splitting. The photocatalysts were prepared using a precipitation procedure both in a "stand-alone" powder form and in form of the Fe 2 O 3 /CeO 2 nanoparticles precipitated on vermiculite (Ver). The phase composition and the specific surface area of the samples, the size and morphology of nanocrystallites of individual phases, and the optical and electronic properties of the photocatalysts were characterized in detail by X-ray powder diffraction, nitrogen physisorption, transmission electron microscopy, diffuse reflectance UV–Vis spectroscopy and work function measurements. Photocatalytic water splitting over the photocatalysts was performed during 8 h in annular batch photoreactor illuminated with 8 W Hg lamp (λ = 254 nm). The most active photocatalysts were Fe 8 Ce 2 both in "stand-alone" powder form and in form of the photocatalyst attached on vermiculite. The photocatalytic generation of hydrogen in the presence of the Fe 2 O 3 /CeO 2 photocatalysts is controlled by the intrinsic photocatalytic properties of the oxides and by the specific surface of the composite. It is enhanced, when heterojunctions between Fe 2 O 3 and CeO 2 form. The work function measurements confirmed the formation of heterojunction Type I with bent bands, which effectively inhibits the recombination of photogenerated charge carriers. In addition, it was confirmed that the anchoring of the photocatalyst on vermiculite does not significantly degrade the photocatalytic activity of the composite. In contrast, even if the amount of the photocatalytically active component was three-times smaller as compared with the photocatalysts without vermiculite, just a slight decrease of the photocatalytic activity was observed. [ABSTRACT FROM AUTHOR]

• Broadening of single GaAs quantum dot photoluminescence (PL) linewidth. • Treatment of the surface by sulphur passivation and oxide encapsulation. • Partial revival of the linewidth and PL intensity by above surface treatment. • Estimation of the random Gaussian fluctuation strength related to line broadening. Epitaxial GaAs quantum dots grown by droplet etching have recently shown excellent properties as sources of single photons as well as entangled photon pairs. Integration in some nanophotonic structures requires surface-to-dot distances of less than 100 nm. This demands a surface passivation scheme, which could be useful to lower the density of surface states. To address this issue, sulphur passivation with dielectric overlayer as an encapsulation is used for surface to QD distances of ≲40 nm, which results in the partial recovery of emission linewidths to bulk values as well as in the increase of the photoluminescence intensity. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Selected hypermineralized bones (rostrum and tympanic bullae) have yet to be characterized for diverse species of whales (Cetacea). Hypermineralization in these structures is an example of extreme biomineralization that, however, occurs at temperatures around 36 °C. In this study we present the results of analytical investigations of the specimen of tympanic bulla isolated from gray whale (Eschrichtius robustus) for the first time. Examination of the internal surface of the bone mechanically crushed under a press revealed the presence of a lipid-containing phase, which did not disappear even after complete demineralization of the bone material. Additionally, analytical investigations including CARS, ATR-FTIR, Raman and XRD confirmed the presence of carbonated bioapatite and a collagen- lipid complex as the main components of this up to 2.34 kg/cm3 dense bone. Our experimental results open the way for further research on understanding of the principles of hypermineralization in highly specialized whale bones. [ABSTRACT FROM AUTHOR]

• a -Chitin scaffolds are compatible with human progenitor cell line (hPheo1) • a -Chitin is compatible with cardiomyocytes differentiated from induced pluripotent stem cells • Tubular a -chitin can be used as template for synthesis of hybrid inorganic catalysts Diverse fields of modern technology and biomedicine can benefit from the application of ready-to-use chitin-based scaffolds. In this work we show for the first time the applicability of tubular and porous chitin from Caribena versicolor spiders as a scaffold for the development of an effective CuO/Cu(OH) 2 catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AM), and as a scaffold for the tissue engineering of selected cells. The formation of CuO/Cu(OH) 2 phases on and within the chitinous tubes leads to a hybrid material with excellent catalytic performance with respect to the reduction of p-nitrophenol. On the other hand, experimental results provide for the first time strong evidence for the biocompatibility of spider chitin with different cell types, a human progenitor cell line (hPheo1), as well as cardiomyocytes differentiated from induced pluripotent stem cells (iPSC-CMs) that were cultured on a tube-like scaffold. [ABSTRACT FROM AUTHOR]

Chitin, as a fundamental polysaccharide in invertebrate skeletons, continues to be actively investigated, especially with respect to new sources and the development of effective methods for its extraction. Recent attention has been focused on marine crustaceans and sponges; however, the potential of spiders (order Araneae) as an alternative source of tubular chitin has been overlooked. In this work, we focused our attention on chitin from up to 12 cm-large Theraphosidae spiders, popularly known as tarantulas or bird-eating spiders. These organisms "lose" large quantities of cuticles during their molting cycle. Here, we present for the first time a highly effective method for the isolation of chitin from Caribena versicolor spider molt cuticle, as well as its identification and characterization using modern analytical methods. We suggest that the tube-like molt cuticle of this spider can serve as a naturally prefabricated and renewable source of tubular chitin with high potential for application in technology and biomedicine. [ABSTRACT FROM AUTHOR]

We report on the observation of nearly maximally entangled photon pairs from semiconductor quantum dots, without resorting to postselection techniques. We use GaAs quantum dots integrated on a patterned piezoelectric actuator capable of suppressing the exciton fine structure splitting. By using a resonant two-photon excitation, we coherently drive the biexciton state and demonstrate experimentally that our device generates polarization-entangled photons with a fidelity of 0.978(5) and a concurrence of 0.97(1) taking into account the nonidealities stemming from the experimental setup. By combining fine-structure-dependent fidelity measurements and a theoretical model, we identify an exciton spin-scattering process as a possible residual decoherence mechanism. We suggest that this imperfection may be overcome using a modest Purcell enhancement so as to achieve fidelities >0.99, thus making quantum dots evenly matched with the best probabilistic entangled photon sources. [ABSTRACT FROM AUTHOR]

Review: 107 refs. [ABSTRACT FROM AUTHOR]