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This study investigated redistributing long inter-set rest intervals into shorter but more frequent intervals at 2 different concentric velocities. Resistance-trained men performed 4 randomised isokinetic unilateral knee extension protocols, 2 at 60°·s−1 and 2 at 360°·s−1. At each speed, subjects performed 40 repetitions with 285 s of rest using traditional sets (TS; 4 sets of 10 with 95 s of inter-set rest) and rest-redistribution (RR; 20 sets of 2 with 15 s inter-set rest). Before and at 2, 5, and 10 min after exercise, tensiomyography (TMG) and oxygenation (near-infrared spectroscopy; NIRS) were measured. NIRS was also measured during exercise, and rating of perceived exertion (RPE) was recorded after every 10 repetitions. At both speeds, RR displayed greater peak torque, total work, and power output during latter repetitions, but there were no differences between TS or RR when averaging all 40 repetitions. The RPE was less during RR at both speeds (p < 0.05). RR increased select muscle oxygen saturation and blood flow at both speeds. There were no effects of protocol on TMG, but effect sizes favoured a quicker recovery after RR. RR was likely beneficial in maintaining performance compared with the latter parts of TS sets and limiting perceived and peripheral fatigue. Novelty Although effective at slow velocities, rest-redistribution was likely more effective during high-velocity movements in this study. Rest-redistribution maintained the ability to produce force throughout an entire range of motion. Rest-redistribution reduced RPE during both high-velocity and high-force movements.

The role of hydrogen bonds in energy redistribution in the cyclic structure of a formamide-water complex has been studied with semiclassical formulations of energy transfer probabilities and solutions of the equations of motion. We show high efficiency of near-resonant vibrational energy from initially excited OH stretching to the first overtone of the bending vibration, which is followed by ultrafast (∼100 fs) energy redistribution in the accepting modes of the complex. A strong coupling of the OH bending vibration with the low-frequency modes generated in the hydrogen-bonding intermolecular regions, especially that formed between the water oxygen and formamide hydrogen, plays the key role of ultrafast relaxation of the overtone mode, transferring energy to the hydrogen bonds and distant functional groups in the complex.

The article discusses the basic regulatory acts governing cadastral work. Using the example of the land survey plan of the Republic of Ufa, the Ufa district of the Republic of Belarus, the main stages of the formation of the land plan were studied and presented: preparatory, desk and field work. The boundary plan for redistribution (cadastral procedure, as a result of which 2 or more plots form new adjacent land plots) is prepared in accordance with the RF Labor Code and orders of the Ministry of Energy of the Russian Federation No. 921, 90. The boundary plan is prepared in special programs. The boundary plan and the application for registration with the cadastre are submitted to the Rosreestr branch in the Republic of Belarus for the registration of the site. After the registration of the land plot, an act of completed work and a registered boundary plan are issued.

The present work details a quantitative investigation into the braze gap width dependence on the initial boron uptake (IBU) phenomena—an event which manifests during the initial stages of brazing of boron-containing filler metals. This was accomplished using in situ cyclic DSC of both full- and half-joint TLPB couples, i.e., IN625/xBNi2/IN625 and IN625/xBNi2. All joints demonstrated a linear relationship between the isothermally solidified gap width with the square root of time which were in excellent agreement with conventional metallographic analysis methods. A conceptual model designed to quantify both the extent of isothermal solidification and IBU during TLPB in terms of the redistribution of boron as borides was implemented. The investigation demonstrated excellent agreement with microstructural and DSC results further supporting the crucial role boride formation has on the kinetics of TLPB.

It is of a great challenge to develop semiconductor photocatalysts with potential possibilities to simultaneously enhance photocatalytic efficiency and inhibit generation of toxic intermediates. In this study, we developed a facile method to induce the La doping and cationic vacancie (VZn) on ZnO for the highly efficient complete NO oxidation. The photocatalytic NO removal efficiency increases from 36.2% to 53.6%. Most importantly, a significant suppressed NO2 production also has been realized. According to the DFT calculations, ESR spectra and in situ FTIR spectra, the introduction of La3+ induce the redistribution of charge carriers in La-ZnO, which promote the production of O2− and lead to the formation of VZn for the formation of OH, contributing to the complete oxidation of NO to nitrate. Besides, the conversion pathway of photocatalytic NO oxidation has been elaborated. This work paves a new way to simultaneously realize the photocatalytic pollutants removal and the inhibition of toxic intermediates generation for efficient and safe air purification.

Summary Understanding and controlling pressure-related structural transformations, which can be utilized to tune functional and mechanical properties of materials, is one of the most important research themes in materials science. However, the underlying mechanism governing pressure-driven phase transformations in high-entropy alloys (HEAs) remains poorly understood. By combining an in situ high-energy X-ray diffraction (XRD) technique and ab initio calculations, we reveal that the face-center-cubic (fcc) phase, rather than the hexagonal-close-packed (hcp) phase, is thermodynamically stable in the MoxCrFeCoNi HEA system under atmospheric conditions. However, a fcc to hcp transformation was identified under pressure, resulting from a pressure-induced electronic redistribution. Remarkably, the valence electron concentration has been further demonstrated as a critical factor for regulating this transformation, the reduction of which by Mo doping can encourage the hcp transformation. Our studies provide new insights into the physical processes underlying the allotropic transformation that enables customized alloy design of high-performance HEAs.

The effect of small rotations of a Laue-interferometer block on the moire pattern is studied as a function of the torque applied around the normal to the large surface of the analyzer block. The stress components are calculated as well. It is shown that increasing the torque moment leads first to a decrease in the moire-band period and, once the torque moment reaches a certain value, their slope changes in the opposite direction, whereas periods enlarge with a further increase in the torque.

In order to optimize hydrogen storage properties of bcc Ti–V–Cr alloys it was found that alloying with a few 4 at% of Zr7Ni10 results in acceleration the hydrogen sorption kinetics in the composite material. The novel intergranular phase plays a role of gate for hydrogen, leading parallel to its easy decrepitate, thus enhancing fast formation of Ti–V–Cr hydrides. Nevertheless, the question on how such a composite microstructure affects hydrogen mobility in the material is still open. Here we report on the results of the studies of hydrogen self-diffusion in hydrogenated (TiCr1.8)1-xVx based alloys (x = 0.2, 0.4, 0.6 and 0.8) carried out using proton nuclear magnetic resonance diffusiometry in a static field gradient. For all compounds the method has proved itself as a powerful tool to probe the microstructure of the multicomponent alloys with inhomogeneous element distribution in a few micrometer scale. It has been found that addition of Zr7Ni10 lowers the activation energy of hydrogen motion in (TiCr1.8)1-xVx alloys and leads appear two different diffusion areas. They can be associated with a redistribution of elements within the intra-granular phase due to opposite substitution of Ti and Ni atoms during synthesis and blurring the boundaries between the intra-granular and inter-granular phases.

Hydrogenation, interesterification, fractionation, and blending are distinct processes that can be applied to modify the physical or chemical properties of fats and oils in order to improve their usefulness. These processes can be used alone or in combination with each other. By combining hydrogenation, fractionation, and interesterification with the simple blending of native and modified oils, it is possible to engineer a wide variety of fats and oils with characteristics suited to specific applications. Hydrogenation is used to convert liquid oils into products having different consistencies, melting points, and textures. On the other hand, interesterification produces changes in physical properties by rearrangement or redistribution of fatty acids within and among the TAGs of oils. Fractionation provides a means of producing fats and oils with sharply defined melting characteristics. Keywords: hydrogenation; structured lipids; interestification; fractionation; blending; hydrolisis; lipid modification; fat; oil

N-doped Co3O4 is a promising electrocatalyst. By means of first principles calculations, various concentrations and spatial arrangements of NO atoms on the surface of Co2O4 were modelled. Mutual interaction of the dopant atoms was analyzed with respect to single NO atom. Charge redistribution, caused by doping, was calculated.

The mechanisms of the selective catalytic reduction of NO with NH3 are under debate, especially in terms of the participation of Bronsted and Lewis acid sites on V2O5/TiO2 catalyst. Our results elucidated the dynamic nature of transformation between Bronsted and Lewis sites on V2O5/TiO2 occurring in SCR-relevant conditions through a series of operando DRIFTS experiments. The reversible change between the two acid sites occurred not only by hydration in the presence of water but also by changing the redox state of the catalyst. We proposed that under reducing conditions, the reduced vanadium sites coordinated with ammonia to serve as additional Lewis acid sites; as a result, the reducing environment enriched the surface with Lewis sites, while the oxidizing environment gave the catalyst surface more Bronsted sites. This in turn suggested that the equilibria between the two acid sites, that is, the B/L ratio, differ depending on the reactants contained in the reaction gas. In a simulated transient SCR reaction, the instantaneous change of the gaseous environment resulted in the redistribution of ammonia on both acid sites, which occurred much more quickly than the reaction with NO. Such observations emphasize the importance of clarifying a NH3-equilibrated surface under reaction conditions when measuring rates of ammonia consumption.

Quantum chemical study has been performed on finite-sized bi-metallic Rh3M alloys, M = Ag, Ir, Pd, Pt, Au, derived from magic cluster, Rh4. Bond length of C–O and N–O are noticed to be elongated in the presence of rhodium alloy clusters. CO2 and NO2 gases are found to be highly adsorbed on Rh3M clusters, which is confirmed by stretching frequency of C–O and N–O. DFT evaluated dipole moment and electronic charge redistribution suggests the sensing capability of CO2 and NO2 gases by Rh3M clusters which is further confirmed by the calculated HOMO–LUMO gap. Mixed rhodium alloy clusters supported on single-wall carbon nanotube (SWCNT) exhibits much higher ability to sense CO2 and NO2. On the other hand, SWCNT@Rh3M shows higher catalytic activity for the activation of CO2 and NO2 in comparison to bare Rh3M because of the higher electronic charge redistribution in the case of SWCNT@Rh3M. In case of SWCNT-supported gas adsorbed clusters, p electrons play a major role in bonding.

Conventional electronic rules, including Jellium and Wade-Mingos rules and so on, have long been successfully dedicated to design superatoms. These rules, however, rely on altering the intrinsic properties, for example, the compositions or the number of valence electrons, of clusters, which is relatively complicated and inconvenient to manipulate, especially in experiments. Herein, by employing density functional theory calculations, the oriented external electric field (OEEF) was demonstrated to possess the capability of precisely and continuously regulating the electronic properties of clusters at will, representing a novel and noninvasive methodology in constructing stable superatoms because it hardly changes the geometries of clusters. More interestingly, the active sites formed by the charge redistribution upon the introduction of an OEEF could significantly promote the catalytic performance of the low-temperature CO oxidation over clusters. Considering the convenient source of the OEEF, the findings highlighted here may boost the potential applications of superatom-assembly nanomaterials in catalysis and materials science.

The local structure, many-body effect, and charge redistribution of Pt and Ni in Pt–Ni alloys (Pt–Ni = 3:1, 1:1, and 1:3) have been studied by X-ray absorption spectroscopy and X-ray photoelectron ...

In the Paso del Norte at the US-Mexico border, water—as an agent of geopolitics, commodification, and social reproduction—produces charged physical spaces and asymmetrical material realities in the...

International audience; The tridentate ligand 1,8-bis-(2,6-diisopropylphenyl)imino-3,6-di-tert-butyl-carbazolate, {CarbDiPP}-, has been used to prepare a variety of complexes of the large alkaline earths (Ae) calcium, strontium and barium. A complex of their smaller congener, magnesium, has also been synthesised. The range of coligands that have been utilised include alkyls, amides, halides and tetrelides. All structurally characterised complexes presented herein are stable in solution and do not undergo ligand redistribution that is otherwise well-known to pollute the chemistry of the alkaline-earth metals. Detailed structural and spectroscopic data for these compounds are discussed. They provide compelling evidence that this nitrogen ligand allows for the kinetic stabilisation of Ae complexes through optimal steric encapsulation of the voluminous metal centres. Its ease of access combined to its evident versatility make {CarbDiPP}H stand out in the portfolio of proligands that have been devised for similar purposes in the past decade. Yet, it fell short in our attempts to synthesise heteroleptic Ae-hydrides upon action of PhSiH3 onto Ae-amides, as the crystallised products showed the imine groups were prone to hydride reduction and formal hydrosilylation.

The optical tuning of the power splitting ratio in an integrated optical Y-splitter fabricated on the substrate of a photorefractive lithium niobate crystal (LiNbO3) has been studied. The areas of the Y-splitter that are most sensitive to local external illumination are determined. Tuning of the splitting ratio by 2% was experimentally demonstrated, which can be effectively used to increase the extinction ratio in Mach–Zehnder modulators.

The increasing scientific interest in the transition from noble metals (Pd, Pt, Rh) to available and environmentally friendly metals (in particular, iron) in the catalyst composition for hydrogenation and hydrogenolysis causes an urgent need to develop new approaches for the preparation and application of effective iron-containing catalytic systems. One of the most promising trends is the preparation of nanoparticles stabilized in the matrix or on the surface of diverse carriers. This review outlines the recent achievements in the application of iron-based heterogeneous catalysts in hydrogenation and hydrogenolysis processes. Special attention is paid to the study of the catalytic properties of bimetallic catalytic systems Fe–Me (Pt, Pd, Cu), as well as the interrelation between the redistribution of the electron density between metals in bimetallic nanoparticles of a noble metal (Pd, Pt) and Fe0 or FexOy, and their activity/selectivity in reactions involving hydrogen: selective hydrogenation of triple CC bonds, NO2– and carbonyl groups.

Four new atomic structures of thiolate-protected gold nanoclusters, namely, Au27(SR)20-, Au32(SR)21-, Au34(SR)23-, and Au36(SR)25-, were predicted via the redistribution of Au-S "staple" motifs on the known Au13 core from experimentally determined Au23(SR)16- and the Au20 core from crystallized Au30(SR)18. Density functional theory calculations show that these structures have large highest occupied molecular orbital-lowest unoccupied molecular orbital gaps and positive vibrational frequencies, indicating their high stabilities. Furthermore, a series of more stable theoretical structures were predicted by introducing triply coordinated μ3-sulfido (μ3-S) motifs to the cores of Au27(SR)20-, Au32(SR)21-, Au34(SR)23-, and Au36(SR)25-. These predicted structures can further confirm the effectiveness and rationality of the ligand-binding strategy for the structural prediction of thiolate-protected gold nanoclusters by redistributing the Au-S "staple" motifs on known cores.

Although Fe has been occasionally recognized as the active site in the electrochemical oxygen evolution reaction (OER), monometallic Fe based catalysts still demonstrate insufficient OER activity in comparison to monometallic Ni and combined Fe–Ni materials. Herein, we report a highly active monometallic Fe catalyst by constructing Fe3O4/FeS2 heterostructures. Particularly, an in situ sulfuration route leads to a series of heterostructured Fe3O4/FeS2 materials which have tunable sulfuration degrees and variable contents of heterogeneous interfaces. At the OER conducted in an alkaline system, the acquired Fe3O4/FeS2-2.5 catalyst with the most abundant hetero-interfaces, exhibits superior performance by delivering ultralow overpotentials and good durabilities. Density functional theory computation reveals that charge redistribution at the interface region decreases the activation barrier for forming oxygen-containing intermediates which greatly accelerates the sluggish OER kinetics. This work clarifies that monometallic Fe based materials can deliver a high OER activity, and Fe should be the actual active site in this reaction. Besides, constructing heterogeneous structures with different anion species which received less attention before, may represent a promising strategy for designing highly active monometallic catalysts.

For aircraft noise calculations, lateral flight dispersion is commonly represented by means of subtracks – a backbone track and side-tracks to each side of the backbone track – where each subtrack is assigned a movement percentage. Aircraft noise calculations impose quality demands on these subtracks, while the latter are often created based on limited information. This paper presents a method to increase flexibility when designing subtracks. The method allows to redistribute subtracks geometrically, allowing for the design of simplified track representations, for instance through a lower number of subtracks and very basic indications of movement allocations. The method is based on the geometric matching of the initial subtracks and on the estimation of the lateral movement distributions for both input and final output subtracks. No restrictions on the number of sub-tracks or on the shape of the distributions are needed, neither for the input nor for the output. A number of examples of the redistribution and its effect on aircraft noise calculations are discussed.

Highly selective CO2 electroreduction to CO (∼90% faradaic efficiency) was achieved on NiCu0.25 bimetallic nanoparticle catalysts. By combining Synchrotron based X-ray absorption and in situ Raman spectroscopy studies, we found that there is a negative correlation between the Cu content in NiCux and CO selectivity due to redistribution of the 3d electrons.

Establishing gene regulatory networks during differentiation or reprogramming requires master or pioneer transcription factors (TFs) such as PU.1, a prototype master TF of hematopoietic lineage differentiation. To systematically determine molecular features that control its activity, here we analyze DNA-binding in vitro and genome-wide in vivo across different cell types with native or ectopic PU.1 expression. Although PU.1, in contrast to classical pioneer factors, is unable to access nucleosomal target sites in vitro, ectopic induction of PU.1 leads to the extensive remodeling of chromatin and redistribution of partner TFs. De novo chromatin access, stable binding, and redistribution of partner TFs both require PU.1’s N-terminal acidic activation domain and its ability to recruit SWI/SNF remodeling complexes, suggesting that the latter may collect and distribute co-associated TFs in conjunction with the non-classical pioneer TF PU.1., PU.1 is a master TF of hematopoietic lineage differentiation. Here the authors analyse properties of PU.1 DNA-binding in vitro and genome-wide in vivo across different cell types with native or ectopic PU.1 expression, and uncover the mechanisms governing the pioneering and redistribution capabilities of the non-classical pioneer PU.1.

International audience; Adaptive coordination-driven supramolecular chemistry based on conformationally flexible pre-organized luminescent Cu(I) precursors paves the way to the ready formation of intricate supramolecular scaffold possessing intrinsic luminescence properties. A formal ring extension of a tetrametallic Cu(I) metallacycle bearing Thermally Activated Delayed Fluorescence (TADF) properties can thus be carried out, affording a new hexametallic Cu(I) metallacycle 1 bearing modulated solid-state TADF properties. Attempts to adapt this ring extension process to the formation of targeted heterometallic Au2Cu4 and Pt2Cu8 assemblies led to the unexpected and ready formation of the Au2Cu10 and Pt4Cu11 derivatives 2 and 3, respectively. These outcomes strengthen the scope and perspectives of adaptive coordination-driven supramolecular chemistry compared to those of conventional coordination-driven supramolecular chemistry. Indeed, it guides concerted intramolecular fragmentation and redistribution of the particular building blocks used, affording selectively supramolecular scaffolds of higher nuclearity and complexity. The study of the solid-state photophysical properties of the assemblies 2 and 3 highlights enhanced and original behaviors, in which the heavy metal spin-orbit coupling values significantly influence the relaxation processes centered on the Cu(I) metal centers.

Purpose To evaluate the efficacy of coil embolization to obtain intrahepatic redistribution in patients undergoing radioembolization. Materials and Method All patients treated with radioembolization at our institute were retrospectively analyzed, and all cases in which a tumor-feeding vessel was coil-embolized were selected. Two nuclear medicine physicians visually assessed the effect of redistribution. Furthermore, the redistribution of microspheres was measured by quantifying the activity distributed to the coil-embolized (dependent) segment relative to the other (non-dependent) segments and to the tumor(s) in that segment. Quantitative analysis was performed on post-treatment 90Y-PET and 166Ho-SPECT using Simplicit90Y software. Lesion response was measured according to RECIST 1.1 criteria at 3 months post-treatment. Results Out of 37 cases, 32 were suitable for quantitative analysis and 37 for qualitative analysis. In the qualitative analysis, redistribution was deemed successful in 69% of cases. The quantitative analysis showed that the median ratio of the activity to the dependent embolized segments and the non-dependent segments was 0.88 (range 0.26–2.05) and 0.80 (range 0.19–1.62) for tumors in dependent segments compared with tumors in non-dependent segments. Using a cutoff ratio of 0.7 (30% lower activity concentration in comparison with the rest of the liver), 57% of cases were successful. At 3 months post-treatment, 6% of dependent tumors had partial response, 20% progressive disease, and 74% stable disease. In non-dependent tumors, this was, respectively, 16%, 20%, and 64%. Conclusion Coil embolization of hepatic arteries to induce redistribution of microspheres has a limited success rate. Qualitative assessment tends to overrate redistribution.

The effect of the properties of modifying additives (Mg and Ca) introduced into nanosized catalytic dispersions on the occurrence of three-phase Fischer–Tropsch synthesis has been studied. It has been found that the introduction of Mg and Ca into the catalytic dispersion composition contributes to a redistribution of oxygen-containing products; namely, it provides a decrease in the yield of the main byproduct—CO2—and an increase in the yield of alcohols dissolved in water.

We use photoinduced absorption spectroscopy (PAS) to study the ionic motion in CH3NH3PbI3 perovskite solar cells, consisting of indium tin oxide (ITO)/NiOx/perovskite/phenyl-C61-butyric-acid-methyl ester (PCBM)/aluminum-doped zinc oxide (AZO)/ITO. We observed a slow (∼50 mHz) spectral blue shift (∼10-4 eV) under modulated 520 nm illumination, which we interpreted in terms of the modulation in the bulk ion density. Numerical simulation shows that the mobile ion moves in and out from the double layers at the perovskite/charge transport layer interfaces in order to recover the bulk charge neutrality tipped off-balance by the photocarriers. The diffusion coefficient of the ion is 10-10 to 10-11 cm2 s-1, when we assume that the characteristic time constant of the ion motion is governed by the diffusion.

Slight orthorhombic and monoclinic distortion of approximately tetragonal lattice in five-layered modulated (10M) martensite of Ni-Mn-Ga leads to the formation of laminates consisting of a/b compound twins. Here, we present the first direct optical observation and x-ray diffraction confirmation of the stress-induced redistribution of a/b twins of ~1–15 μm in size. We demonstrate that a/b twins are highly mobile, exhibiting twinning stress as low as 0.1 MPa, which is comparable to the twinning stress of Type 2 a/c twin boundaries. We assume that a local rearrangement of the a/b laminate may occur during the motion of a/c twin boundaries.

An in-depth understanding of the microscopic reaction mechanism on a nonmetal-doped catalytic system at the atomic level is one of the critical approaches to developing new efficient catalysts. Herein, the effects of S-doping on melon-based carbon nitride (CN) for the photocatalytic selective oxygen reduction reaction (ORR) have been comprehensively investigated by first-principles calculations. The configurations, electronic properties, optical properties, and the reaction performance of the S-doped melon-based CN have been studied and discussed. The results demonstrate that the decoration with S atoms exhibited substantial effects, involving the redistribution of the charge density and tuning of the bandgap, which promote the photocatalytic selective ORR activity. Accordingly, O2 is activated on the S-doped system with about 0.4 e of charge obtained from catalytic surfaces, leading to the thermodynamically feasible H2O2 and H2O formation, which is in good agreement with the experimental results. Our results provide theoretical insights into the design and development of polymeric carbon nitride (PCN) as well as other metal-free photocatalysts for the selective ORR.

Various borohydrides were found to catalyze the redistribution reaction of hydrosilane and chlorosilane in different solvents to produce hydrochlorosilanes efficiently and facilely. The redistribution reaction was affected by solvent and catalyst. The substrate scope was investigated in HMPA with LiBH4 as catalyst. A possible mechanism was proposed to explain the redistribution process.

All-perovskite tandem solar cells have great potential to realize the efficiency beyond the Shockley-Queisser efficiency limitation of single junction solar cells. Here we investigate the photon redistribution effect induced by introduction of the optical coupling layer in two terminal (2 T) tandem solar cells. In this work, it is shown that the introduction of the optical coupling layer could not only reduce the reflection loss, but also would affect the redistribution of the absorbed photons in the tandem device due to the optical interference effect, which will disturb the previous balance and complicate the optical modulation. This photon redistribution phenomenon is systemically investigated by combining the optical and electrical aspects. By considering the coupling effect beyond the antireflection function after introducing the optical coupling layer, the new current match could be achieved, which would obviously improve the device performance further. Various materials such as LiF, MgF2, Al2O3, ZnO have been adopted as the optical coupling layer and it is demonstrated that this phenomenon is universal for all the cases. The improvement brought by photon redistribution effect may be even more obvious than antireflection function. Through analyzing the inner optical mechanism and modulating the structure, a higher performance can be achieved by carefully considering the optical coupling effect.

The performance of MoS2 based devices is closely related to the quality and defect morphology of the monolayer MoS2 deposited on metal. First-principles calculations were performed to investigate the vacancy effects of Au–mMoS2 contact. Four possible S-vacancy and a Mo-vacancy were considered in our calculations. Energetic studies show that S-vacancies are easier to form than Mo-vacancy in Au–mMoS2 contact, while S-vacancy (hollow site at interface, VS4) has the lowest formation energy under Mo-rich environments. Electron and charge redistribution analysis of defective Au–mMoS2 contact indicate that the lower contact resistance and higher electron injection efficiency of defective Au–MoS2 contact than perfect ones. Notably, the S-vacancy at top layer showed better electronic performance than that at bottom layer of monolayer MoS2 in the contact. High quality n-type Au–mMoS2 contact can therefore be expected through defect engineering.

The effect of a static magnetic field on the redistribution of the stochastic energy in an ensemble of charged particles in an electrostatic trap has been studied numerically and analytically. The simulation has been performed for cluster systems of particles with the Coulomb interaction in a wide range of their parameters. Conditions of energy balance have been proposed for charged particles in systems with spatially inhomogeneous heat sources.

The aim of this paper is to analyze the effect of diverse cyclic loading conditions on the residual stress field in cold-drawn pearlitic steel wires. To this end, on one hand, a numerical simulation by the finite element method of the manufacturing process (cold drawing) of a prestressing steel wire was carried out for revealing the residual stress state induced by the manufacture technique. On the other hand, a numerical simulation was performed of the in-service fatigue loading applied to a cold drawn wire (including the manufacturing-induced residual stress-strain state). According to the obtained results, the plastic strain generated during fatigue loading causes a reduction of the initial residual stress at the surface and a redistribution of the residual stress field.

The involvement of Lewis and Bronsted acid sites on V2O5/TiO2 catalyst in the selective catalytic reduction of NO with NH3 (NH3-SCR) is under debate. Here, a Li doping strategy is applied to selectively block Bronsted sites, which aims to prepare model catalysts with the same V loading but different ratios of the two acid sites. Time-resolved in situ DRIFTS observation demonstrates that the surface ammonia species pre-adsorbed on Lewis and Bronsted sites can participate equally in the reaction. Consideration of site redistribution in the early stages of the transient reaction is key to accurate measurement of the ammonia consumption rate.

The results of investigations of the complexation of N-vinylsuccinimide (VSI) in monomer–solvent and monomer–monomer systems and the effect of these processes on the kinetics of copolymerization of VSI with monometers of differing reactivity are summarized. Conditions for the synthesis of compositionally homogeneous copolymers were established. Taking into account the electronic structure of VSI and co-components, a mechanism of complexation in VSI–dimethylsulfoxide, VSI–acetic anhydride, and VSI–maleic anhydride systems is proposed. The electron density redistribution in the VSI molecule upon complexation has been quantitatively assessed.

Rare-earth metal tris(aminobenzyl) complexes Ln(CH2C6H4NMe2-o)3 (Ln = La, Y) were grafted onto the dehydroxylated periodic mesoporous silica support SBA-15 to generate the organometallic-inorganic hybrid materials Ln(CH2C6H4NMe2-o)3@SBA-15 (Ln = La (2a), Y (2b)), which demonstrated extremely high selectivity (>99%) in catalyzing the redistribution of primary arylsilanes to secondary arylsilanes without the requisition of strict control of the reaction conditions. The hybrid materials still showed a perfect selectivity and activity after three catalytic cycles.

The reactions of the boryl-substituted stannylene Sn{B(NDippCH)2}2(1) with carbon dioxide have been investigated and shown to proceedviapathways involving insertion into the Sn–B bond(s). In the first instance this leads to formation of the (boryl)tin(II) borylcarboxylate complex Sn{B(NDippCH)2}{O2CB(NDippCH)2} (2), which has been structurally characterized and shown to feature a κ2mode of coordination of the [(HCDippN)2BCO2]−ligand at the metal centre.2undergoes B–O reductive elimination in hexane solution (in the absence of further CO2) to give the boryl(borylcarboxylate)ester {(HCDippN)2B}O2C{B(NDippCH)2} (3)i.e.the product of formal diboration of carbon dioxide. Alternatively,2can assimilate a second equivalent of CO2to give the homoleptic bis(borylcarboxylate) Sn{O2CB(NDippCH)2}2(4), which can be preparedviaan alternative route from SnBr2and the potassium salt of [(HCDippN)2BCO2]−, and structurally characterized as its DMAP (N,N-dimethylaminopyridine) adduct. Structural and reactivity studies also point to the possibility for extrusion of CO from the [(HCDippN)2BCO2]−fragment to generate the boryloxy system [(HCDippN)2BO]−, a ligand which can be generated directly from1viareaction with N2O. The initially formed unsymmetrical species Sn{B(NDippCH)2}{OB(NDippCH)2} has been shown to be amenable to crystallographic study in the solid state, but to undergo ligand redistribution in solution to generate a mixture of1and the bis(boryloxy) complex Sn{OB(NDippCH)2}2.

Mining of the coal seam adjacent to the extracted coal panel is widely practiced in China to improve coal resource recovery rates, but the energy change associated with longwall mining may present a new risk to ground stability and gateroad failure. To understand the energy change effectively, a meticulously validated numerical model, built using FLAC3D software, incorporating a double‐yield model for the gob materials and a strain‐softening model for the coal/rock masses, was developed to investigate the energy redistribution in coal seams and barrier pillars during the process of mining the coal seam adjacent to the extracted coal panel. The model results showed that the closer the region was to the LW 5301 gob, the higher the location and magnitude of the peak strain energy density. Consequently, the risk of rockburst in coal seams was greater than that in barrier pillars. Along the coal seam strike, with increasing advancing distance from the setup room, the magnitude of the peak strain energy density gradually increased to 1.88‐2.78 times the premining energy level. In addition, along the coal seam dip, the maximum distance from the peak strain energy density to the edge of the coal seam was approximately 16‐28 m, which is greater than that in the barrier pillar. The proposed numerical simulation procedure and calibrated method could be a viable alternative approach to evaluate longwall mining‐induced energy changes.

The article analyzes the issues related with the formation mechanism and the selection into an independent form, the so-called "ionelectrostatic bonds" in clay soils, allegedly causing the forces of attraction between the particles. The article notes that direct evidence of the existence of these bonds in dispersed systems does not exist, and the above arguments presented in the domestic and foreign literature are not consistent or erroneous. Moreover, in modern foreign literature on research in the field of surface forces (J. Israelashvili and etc.), these “connections” are not mentioned at all. Nevertheless, it was the presence of this type of bonds in the domestic soil science that explained the hardening of clays during drying or dehydration, i.e. the nature of point (or transitional) contacts between clay particles was associated precisely with the presence of such structural bonds in soils. This article shows that point contacts in clays during drying can be formed not due to “ion-electrostatic bonds”, but due to the phenomenon of so-called “self-assembly”, which leads to redistribution of different components in the contact gap between clay particles of various components during drying of clays – ions of soluble salts and solid nanoparticles. The formation of the structural adhesion of clay particles due to transitional contacts is based on the processes: a) “selfassembly” due to crystallization of water-soluble salts in the contact gap; b) “self-assembly” due to redistribution of nanoparticles in the contact gap; c) increasing the area of contact between clay particles due to “self-assembly” processes. All known phenomena of the formation of structural adhesion between clay particles during compaction of pastes and powders, squeezing of a pore solution or hydrationdrying, etc. can be explained without taking into account the hypothetical "ion-electrostatic forces", and due to the phenomena of “self-assembly”.

The dynamics of global flows of matter in the biosphere has been studied. The general law of redistribution of average elemental compositions in the biosphere between the solid and liquid phases (lithosphere-hydrosphere) is established. In these processes, the main role is played by "living matter." The most active processes of redistribution of mean elemental compositions in the biosphere take place in the places of "life thickening" (biogeochemical barriers) such as ocean-atmosphere, river-sea and hydrosphere-lithosphere. The result of these processes is a general relative increase in the concentrations of trace elements in the environment of living organisms. A new methodological approach is proposed to study the role of the transfer of trace elements in the ocean-atmosphere-continent system as a factor in the formation of the elemental composition of the Earth's soil cover.

The main stages of the interaction of medical devices as an implant in contact with blood are analyzed and the hemosumicity aspects of materials in contact with albumin are determined. Glass-crystalline materials based on ceramic technology were developed under the conditions of one-stage high-speed heat treatment and their structural parameters were calculated. The redistribution of free and bound calcium after exposure to bioactive glassy-crystalline materials in an albumin solution is established taking into account the characteristics of their surface structure. The hemocompatibility of the developed calcium silicophosphate materials was determined and their potential was evaluated in the development of bone endoprostheses.

The impact of halogens (Cl2 and Br2) and hydrogen halides (HCl and HBr) on the structural stability of zeolite catalysts constitutes an important yet poorly understood aspect of their performance i...

Activating pretreatments are used to tune surface composition and structure of bimetallic-alloy catalysts. Herein, the activation-induced changes in material properties of a nanoporous Ag0.03Au0.97 alloy and their subsequent evolution under steady-state CH3OH oxidation conditions are investigated. Activation using O3 results in AgO and Au2O3, strongly enriching the near-surface region in Ag. These oxides reduce in the O2/CH3OH mixture, yielding CO2 and producing a highly Ag-enriched surface alloy. At the reaction temperature (423 K), Ag realloys gradually with Au but remains enriched (stabilized by surface O) in the top few nanometers, producing methyl formate selectively without significant deactivation. At higher temperatures, bulk diffusion induces sintering and Ag redistribution, leading to a loss of activity. These findings demonstrate that material properties determining catalytic activity are dynamic and that metastable (kinetically trapped) forms of the material may be responsible for catalysis, providing guiding principles concerning the activation of heterogeneous catalysts for selective oxidation.

Using methods of electron-microscopy and x-ray structural analysis, we have investigated peculiarities of the evolution of the structural-phase state of an alloy of the system Ti–Al–V–Мо during formation of an ultrafine-grained structure by a method combining hot plastic deformation and reversible hydrogenation. It has been shown that the presence in solid solution of 0.15 wt% hydrogen makes it possible to lower by more than a factor of 2 the magnitude of the plastic deformation needed to obtain an ultrafine-grained state in the alloy. We found that during deformation and subsequent degassing of hydrogen from the alloy, such processes as the phase transformations α′′→β→α and β→α′′ and a redistribution of the doping elements take place, facilitating the formation of a lamellar morphology in the grains and preservation of a high level of strength properties of the ultrafine-grained structure.

As-cast Mg–Sn alloys (3, 6, and 9 wt% Sn) were solution treated at 653, 703 and 753 K (380, 430 and 480 °C) for 1, 4, 8, 12 and 24 h to determine the variation of secondary phase with respect to Sn content, temperature and time. Mg-3 wt% Sn exhibits Mg2Sn dissolution at all solution treatment temperatures whereas Mg-6 and 9 wt% Sn alloy displays Mg2Sn reprecipitation and dissolution depending on the heat treatment temperature. In addition, a combined mathematical model that predicts the secondary phase dissolution and solute redistribution as a function of temperature and time is presented in this work. This model is a significant improvement compared to the previous studies where the dissolution and homogenization processes are considered independently. The effect of grain size and solute mobility upon the dissolution and homogenization kinetics is discussed as well. Keywords: Solution treatment, Homogenization, Dissolution, Mg–Sn alloys