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Athermal quasi-static compressive deformation for a model metallic glass is investigated by molecular dynamics simulations. A new structural parameter, quasi-nearest atom (QNA), is used to characterize local atomic packing of initial structure. We find that regions with higher nonaffine displacement have more atoms with more QNA. The coarse grained number of QNAs exhibits significant spatial heterogeneities and these structural fluctuations show close correlation with the nonaffine displacement. The correlation between the coarse grained number of QNA and nonaffine displacement does not decrease as the strain increases but show the maximum at a certain strain, indicating that strain localized regions are activated individually. Therefore, our results provide a direct evidence of the correlation between atomic structure and deformation in metallic glass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-scale formation mechanism of the ionic liquid emulsion reactor was revealed. • Prepared temperature and CO 2 -responsive emulsion reactors for Knoevenagel reaction. • Homogeneous reaction, heterogeneous separation, and catalyst recovery were achieved. Knoevenagel condensation reaction is important for generating C C double bonds and providing various valuable intermediates in organic chemistry, which always need harsh conditions including high reaction temperature, difficult catalyst recovery, difficult product separation, etc. In this work, a novel class of dual-responsive emulsion reactor was prepared for the Knoevenagel condensation reaction between malononitrile and aromatic aldehyde, where the temperature and CO 2 -responsive ionic liquids (ILs) were used as an emulsifier, responder, and catalyst simultaneously. Driven by temperature or CO 2 , the emulsion reactor undergoes reversible and controllable transformations between emulsification and demulsification, where efficient catalytic reactions, product separation, and reactor recovery are all achieved. The isolated product yield of 2-(4-chlorobenzylidene)-malononitrile remained above 90% after 5 cycles of the emulsion reactor. NMR and molecular dynamics simulations showed that the temperature drives the reversible stretching and curling of the polyether chain on the cation, while CO 2 reacts with the –COO- group on the anion to form carbonates and carboxylic acids in water, leading to changes in the surface activity of ILs, thereby reversibly regulating the demulsification and emulsification of the emulsion. Hence, through the dual stimuli-responsive ILs, the efficient reaction can be performed in the homogeneous phase, and the products and catalysts can be easily separated in the heterogeneous phase. These results on the revisable microreactor can not only help to design the smart and efficient "homogeneous reaction-heterogeneous separation" systems but also support the development of green sustainable chemistry. [ABSTRACT FROM AUTHOR]

σ and μ phases are two of the most common topological close-packed (TCP) phases in nickel-based single crystal superalloys, which are detrimental to the comprehensive properties of superalloys. It is universally acknowledged that Ru plays an important role in the precipitation of TCP, and its inhibiting effects on the nucleation and precipitation of μ phases have already been confirmed, but its effects on σ phases remain vague. In this work, the types and area fractions of the TCP phases precipitated from 4 alloys with different compositions have been characterized. It is found that Ru has different effects on the precipitation of different types of TCP. With the help of density functional theory (DFT), the interface structures between σ and matrix γ are further studied, and on this basis, the effects of different solutes such as Ru on interface stability and electronic structure are discussed in detail. Ru, Re, W, Cr and Ta are able to enhance the interface stability, boosting the nucleation of σ phase. Co is different, for it can reduce the interface stability and elevate the nucleation difficulty of σ. Additionally, the distribution behaviors of solutes between σ and γ phases have been calculated, from which it can be found that the energies of solutes like Cr and Ru distributing in σ are more stable than distributing inside γ, and these solutes have the tendency to diffuse from γ to σ. These results reveal the effects of solutes like Ru on the precipitation of σ phase in terms of interfacial stability and atomic diffusion, which provide a new understanding of Ru effects. • Ru has different effects on the precipitation of different types of TCP phases. • Solutes like Ru enhance the σ/γ interface stability and promote the nucleation of σ. • Unlike Ru, Co can reduce the σ/γ stability and elevate the nucleation difficulty of σ. • Like other solutes, Ru also has a tendency to diffuse from γ to σ during the growth of σ. • Ru Effects are explained from aspects of interface stability and atomic diffusion. [ABSTRACT FROM AUTHOR]

• Strong bonding is present in Cu-Si pair; while in the Cu-Cu and Cu-Nb pairs almost no bonding exists. • We further suggest that the addition of Cu in this quinary amorphous alloy is to promote FeSi cluster units to separate from FeB cluster units. • The Cu-centered cluster connections by one-atom-shared are favored in this quinary amorphous alloy. • The value of B s is 1.28T at 300K, which is close to the experimental value. The chemical environments around Cu in amorphous Fe 73.5 Si 9 B 13.5 Cu 1 Nb 3 alloy were investigated by ab initio molecular dynamics simulation. It is found that there is strong bonding in Cu-Si pair, while almost no bonding exists in Cu-Cu and Cu-Nb pairs. Comparing to the random distribution, Cu tends to attract more Si atoms while to repulse B atoms. Based on the local structure information around Cu atoms, we suggest that no pure Cu cluster exists in this quinary amorphous alloy at 300K. The statistics of vertex/edge/face/intercross shared clusters centered on Cu show that the cluster connections by one-atom-shared are favored in this quinary amorphous alloy, accounting for 23%. The increase in magnetic moment occurs due to the increased average atomic distance caused by the addition of Cu and Nb. The value of B s is 1.28T at 300K, which is close to the experimental value. [ABSTRACT FROM AUTHOR]

Antimony (Sb) as a low-toxic and cost-effective metal is a promising material to catalyse CO 2 electroreduction to formate with practical viability. However, monometallic Sb suffers from intrinsically low catalytic activity and the competing hydrogen evolution. Here, we report nanoporous Sb-Bi alloys for substantially improving the catalytic activity of Sb and suppressing hydrogen evolution. The optimal Sb-Bi alloy exhibits a maximum Faradaic efficiency of 95.8 % toward formate production, surpassing the 11.6 % of monometallic Sb counterpart. Operating the catalyst in the flow cell demonstrates a formate partial current density of 734 mA cm−2 and cathodic energy efficiency of 59 % at a moderate overpotential of 800 mV, representing a record formate-production performance so far. Experimental and theoretical studies indicate that the Sb-Bi interactions activate Sb sites to selectively stabilize *OCHO intermediates, facilitating CO 2 -to-formate conversion. This work offers insights in manipulating bimetallic interactions to transform inert materials into active catalysts for efficient electrocatalysis. [Display omitted] • Sb-Bi interactions induce electrocatalytic switching from HER to CO 2 ER. • Sb 2 Bi 6 exhibits a maximum formate selectivity of 95.8 % in an H-type cell. • Sb 2 Bi 6 achieves a record formate activity of 734 mA cm−2 in a flow cell. • Sb-Bi interactions facilitate Sb sites to stabilize *OCHO for formate formation. [ABSTRACT FROM AUTHOR]

The structures of liquid Fe–C alloys in the Fe-rich end were investigated by ab initio molecular dynamics simulations. The trend of intensity of chemical short range order around Fe and C atoms changes at the eutectic composition, indicating the close correlation between liquid structure and phase diagram. The tri-capped trigonal prism (Voronoi index <0,3,6,0>) and mono-capped square archimedean antiprism (Voronoi index <0,4,4,0>) around C atoms have the largest frequency fractions and the longest lifetimes among all the polyhedra. Moreover, they tend to connect with each other to form network structure. The maximum intensity of network structure is located at the 20% C composition, which might be the reason why alloys near eutectic composition have great glass-forming ability. [ABSTRACT FROM AUTHOR]

• Unlike other solutes, Ti can greatly elevate difficulty of nucleation of D0 19 phase. • Ti, Cr, Ru, Re have larger trends to diffuse from γ to D0 19 during the growth of D0 19. • Ti has the least promoting effect on μ/γ interface stability and nucleation of μ. • Ru no longer inhibits the nucleation of μ phase as it does in Ni-based superalloy. • Unlike other solutes, Ti has no tendency to diffuse from γ to μ during the growth of μ. D0 19 -Co 3 X and μ-Co 7 X 6 are two common detrimental phases in Co-based superalloys. In this work, the D0 19 -Co 3 X/γ and μ-Co 7 X 6 /γ interfaces were studied by density functional theory (DFT) calculation. On this basis, the influence of different solutes on the interfacial stability has been analyzed. For the D0 19 /γ interface, Ti can lower its stability and reduce the driving force of D0 19 's nucleation, which is different from other elements. W, Re, and Ru can increase the interfacial stability, promoting the nucleation of D0 19. For μ/γ, these solutes all increase the work of separation of the interface, but compared with other solutes, Ti can hardly improve the work of separation and facilitate the nucleation of the μ phase. In addition, the solute distribution behaviors between D0 19 (or μ) and γ have been discussed. It is found that when solutes such as Ti are distributed in D0 19 , the energies are all more stable than they are inside γ, and they all have the tendency to diffuse from γ to D0 19. For the μ and γ phases, Ti is different from other solutes since its energy to distribute in γ is more stable than that distributed in μ. During the growth of μ, the Ti inside γ has no tendency to diffuse toward μ. These results reveal the solutes' effects on the precipitation of the D0 19 and μ phases at the atomic scale from the perspective of interfacial stability and atomic diffusion. [ABSTRACT FROM AUTHOR]

The liquid structure of seven representative Fe–Si–B alloys has been investigated by ab initio molecular dynamics simulation focusing on the role of clusters in terms of glass-forming ability (GFA) and crystallization. It is demonstrated that the type of primary phase precipitated from amorphous state under heat treatment is determined by the relative fraction and role of various clusters in melt. The alloy melt shows higher stability and resultantly larger GFA when there is no dominant cluster or several clusters coexist, which explains the different GFAs and crystallization processes at various ratios of Si and B in the Fe–Si–B system. The close correlation among clusters, crystalline phase and GFA is also studied. [ABSTRACT FROM AUTHOR]

Bisphenol S (BPS), widely utilized in manufacturing of daily necessities, is a toxicant with potential to induce atherosclerotic cardiovascular disease (ASCVD). However, the mode of action by which BPS exposure induces ASCVD remains unknown. Here, macrophages that were exposed to BPS in combination with oxidized low-density lipoprotein (oxLDL) exhibited enhanced formation of foam cells, a hallmark of ASCVD. Furthermore, zebrafish embryo-larvae were exposed to BPS (0, 1, 10 and 100 μg/L) for 15 days (d) and the characteristic symptoms of ASCVD including an inflammatory response, macrophage recruitment around blood vessels, and accumulation of oxLDL on vascular endothelium, were induced in 15-d larvae. After zebrafish were exposed to BPS for 45 d, BPS mobilized fatty acid metabolism and activated peroxisome proliferator-activated receptor signaling in larval liver, the hub of endogenous lipid metabolism, causing an increase in plasma LDL. Driven by high plasma LDL levels, the caudal artery of zebrafish larvae exhibited lipid accumulation and a thickened area with a large number of collagen fibers, accompanied by characteristic lesions, as well as hyperlipidemia, erythrocyte aggregation, thinner blood vessel walls and increased levels of leukocytes and thromboocytes in plasma. Our data demonstrate that BPS accelerates the progression of ASCVD using zebrafish embryo-larvae as a model. [Display omitted] • BPS induces macrophages foaming and macrophage recruitment around the blood vessels. • BPS causes exogenous oxLDL accumulation within blood vessels. • BPS disrupts the endogenous lipid metabolism in zebrafish larvae. • BPS induces characteristic ASCVD lesions in the caudal artery of larvae. [ABSTRACT FROM AUTHOR]

• Heterostructured g-C 3 N 4 /Ti 3 C 2 T x endows electrode with enhanced structural stability and fast charge transfer. • The heterostructured g-C 3 N 4 /Ti 3 C 2 T x delivers superior aluminum-storage performance. • The charge-discharge mechanism for g-C 3 N 4 /Ti 3 C 2 T x is reversible intercalation of chloroaluminate anions. [Display omitted] As a compelling complement to lithium batteries, rechargeable aluminum batteries (RABs) have attracted considerable attention because of abundant natural resources, high volumetric capacity, and safety property of aluminum metal. However, the deployment of RABs is hampered by the lack of favorable cathodes with high capacity and rapid kinetics. To address the long-unresolved issue of aluminum-storage capacity and rate, here we design a heterostructured g-C 3 N 4 /Ti 3 C 2 T x hybrid which offers a conductive supporting framework to maintain structural integrity and accelerate electronic transport. The energy storage mechanism of the heterostructured g-C 3 N 4 /Ti 3 C 2 T x cathode was demonstrated as the reversible intercalation of AlCl 4 − during cycling. Moreover, the battery-capacitance model mechanism in the heterostructured g-C 3 N 4 /Ti 3 C 2 T x hybrids may accelerate the kinetics of the electrode reactions. Furthermore, DFT calculations certify that heterostructured g-C 3 N 4 /Ti 3 C 2 T x possesses enhanced electrical conductivity and Al trapping capability. Accordingly, the heterostructured g-C 3 N 4 /Ti 3 C 2 T x cathode affords RABs with an excellent Al-storage property (237 mAh g-1 at 0.5 A g-1) and considerable rate capabilities (174 mAh g-1 at 4 A g-1) among state-of-the-art cathode materials for aluminum batteries. [ABSTRACT FROM AUTHOR]

HAADF-STEM observations illustrate that the probabilities of appearance of (111) microtwins with different twinning structures in μ phase were different. Based on this, 8 possible (111) twinning models with different twin boundary structures are established and discussed via DFT. Experimental characterization and DFT calculations reveal a close relation between the probabilities of appearance of these (111) microtwins and the interface energy at the twin boundaries: the smaller the energy is, the easier the twinning structure is to form and exist stably. TB5, with the smallest interface energy, is exactly the abundantly-existing twinning structure observed in HAADF. Moreover, via DFT simulation, distribution behaviors of the solute elements Cr, Mo, Re, Ni at the twin boundary of TB3 and the atomic arrangement at (111) twin boundary of C15–Cr 2 Nb crystal have been predicted and analyzed. The methods of DFT simulation and analysis on the twin boundaries provide a new strategy to study the twinning structures of complex-structured crystals and preferred distribution of different solutes at the twin boundary, etc. • HAADF show different probabilities of appearance of μ (111) twins with different structures. • 8 possible (111) μ microtwins' interface energy are calculated and discussed by DFT. • The smaller the interface energy of TBs is, the easier the TBs is to exist stably. • DFT predicts the preferred distribution of Cr, Mo, Re, Ni at TBs of μ phase. • The most stable twin structure of C15–Cr 2 Nb (111) is predicted by DFT calculation. [ABSTRACT FROM AUTHOR]

Observation regarding the SEM and TEM images of the precipitation and growth morphology of topologically close-packed (TCP) phase indicates that the orientation relationships between the TCP phase with different morphologies and the matrix are not that similar. Concerning with this phenomenon, via DFT calculations, the possible interface structures between the σ phase and the matrix γ, as well as the μ phase and the matrix γ have been established and discussed under different orientation relationships. The experimental characterizations and simulated calculations reveal that the orientation relationships between TCP phase and the matrix determine interplanar spacing mismatches and the interface energy of the low index dense arrangement interfaces of the two phases, while the two parameters exert influence on the growth and morphology of TCP phase. The interface energy of the σ/γ interface with (111) γ //(001) σ orientation is small while its interplanar spacing mismatch is large, so the TCP phase under this orientation relationship tend to take planar expansion along interface instead of growing layer by layer parallel to the plane, giving rise to plate-like morphology. However, those of the σ/γ with (110) γ //(1–10) σ and the μ/γ with (110) γ //(111) μ are just the opposite, so the TCP phases under these orientations tend to grow layer by layer instead of expand along plane, forming needle-like or rod-like morphology eventually. • Building TCP/γ interfaces under different orientation relationships (ORs) via DFT. • Different ORs between TCP phases and γ correspond to different morphologies of TCP. • Interface energy γ i of (001) σ /(111) γ is small, and spacing mismatches δ d of it is big. • The γ i of (1–10) σ /(110) γ and (111) μ /(110) γ are big, and the δ d of them are small. • The two parameters δ d and γ i combined to influence the growth and morphology of TCP. [ABSTRACT FROM AUTHOR]

Abstract: The atomic and electronic structures of several well-selected Al70LM20EM10 (LM=Fe, Co and Ni, EM=Ti, Zr, Hf, V and Cr) melts were investigated systemically by the first-principles method. Structural parameters of liquid Al70LM20EM10, such as partial pair correlation functions and coordination numbers, reveal manifest change trends with LM and EM elements, and are closely correlated with the variations of their glass-forming ability as observed experimentally. LM elements (Fe, Co and Ni) have a strong interaction with Al atoms, while the LM–Al bond strength increases slightly from Fe to Ni. As EM elements added into liquid Al–LM alloys, the local structures around EM atoms change from Ti to Cr regularly that the Zr and Hf intend to be distributed uniformly in the Al–LM matrix while V and Cr like to be self-coordinated. [ABSTRACT FROM AUTHOR]

Abstract: Liquid structure features of isomorphous Ag–Au alloys were investigated using an X-ray diffractometer. The mean nearest neighbor distance r 1 of Ag–Au melts at the same temperature remains stable at different compositions. For the eutectic melts under discussion, r 1 takes on a linear relationship with element component, and the slope of r 1 versus composition depends on the atomic size ratio. In addition, r 1 of both Ag–Au and Cu–Ni isomorphous melts stays stable with decreasing temperature above liquidus. Compared to these isomorphous alloys, the temperature-dependent r 1 of eutectic melts obviously exhibits. The structural differences of melts between isomorphous and eutectic alloy systems, as well as the correlation between liquid structure and the corresponding solid state were investigated. Finally, Gaussian decomposition was performed to get a better understanding of the liquid structures of Ag–Au alloys. [ABSTRACT FROM AUTHOR]

Abstract: In situ nano-scale Cu–Cu2O composites have been prepared by addition of K2TiF6 and KBF4 into Cu melt, and the microstructure, resistivity and microhardness of Cu–Cu2O composites have been studied in this work. Cu2O (100–300nm) in the Cu matrix can be obtained by addition of oxidation agent (K2TiF6 and KBF4), and when the addition level is 3wt%, hyper-Cu–Cu2O can be obtained with constitutes of copper matrix, reinforcing particles-Cu2O (100–300nm), and some nano-scale particles. It is found that the resistivity of Cu–Cu2O composites are close to those of pure copper at 20°C. In addition, the hardness of the composite has been improved significantly as compared to those of pure Cu. [Copyright &y& Elsevier]

• The effect of additional element dissolving on the solid solubility of Zn in Mg alloy is predicted. • Ca is predicted as the element enhancing the solid solubility of Zn. • The properties of the element enhancing the solid solubility of Zn in Mg alloy are given. The solid solubility of Zn is an important factor for designing the Mg-Zn based alloy. This work aims at developing a strategy to predict the effect of additional element dissolving on the solid solubility of Zn in Mg alloy based on the first-principles calculation. The strategy is composed of two criteria. The behaviors of X in controlling the lattice distortion and energy fluctuation caused by Zn-Mg interaction are investigated as the main criterion, and the precipitation of Zn accelerated by Zn-X interaction is further examined as the supplementary criterion. After considering the metallic elements across the periodic table (period II to VI), Ca is recommended as the element enhancing the solid solubility of Zn and the others are recommended as the elements reducing the solid solubility, which has a considerable agreement with the available thermodynamic assessments. The first-principles strategy suggests that an element X enhancing the solid solubility of Zn in Mg alloy should satisfy two conditions. Firstly, X can provide the opposite geometric and energetic effect of single Zn on Mg host, and secondly, there is no attractive interaction between Zn and X. This work explores a pathway for extending Hume-Rothery rules from the binary alloy system to the ternary, which serves the development of alloy design theory. [ABSTRACT FROM AUTHOR]

Abstract: X-ray diffraction experiment has been carried out on In30Sn70 binary alloy from normal liquid 400 °C to the temperature near the solidus 125 °C ( and is about 172 and 120 °C, respectively). The results show that the correlation radius , the correlation length D and the atom numbers have an abrupt increase near the liquidus with the temperature decreasing. Which indicates an abrupt structure change in the nucleus forming process. This result is different from our recent study on Cu80Ag20 alloy, which show a stable structure change around the liquidus. In addition, the coordination number comparing with the viscosity measurement indicates a temperature and component induced discontinuous structural change region between about 165 and 145 °C. [Copyright &y& Elsevier]

The molecular-dynamics (MD) simulation on liquid Al80Fe20 alloy is carried out to investigate the medium-range order (MRO) structure at the cooling rate of 2.6×1013 K/s. The pre-peak in the structure factor S(Q) as the signature of MRO is observed in the experiment, which is in good agreement with our simulation in the equilibrium liquid state (1450 K). With temperature decreasing, the intensity of pre-peak gradually increases, and the second peak begins to split into two peaks below 700 K. It is shown from the analysis of S(Q) that MRO structure will attribute to the icosahedral local order the in the system. The Ashcroft–Langreth (A–L) structure factor exhibits the preference of heteroatomic interaction. It is found from the Bhatis–Thornton (B–T) structure factors that the pre-peaks in total structure factors at different temperatures originates from the chemical ordering in the system. [Copyright &y& Elsevier]

• A simple liquid Ga assisted-alloying/dealloying strategy to fabricate nanoporous Ag. • The thickness of alloy layer/nanoporous Ag varies with the mass loading of Ga. • The bimodal wire-like and unimodal bulk-like nanoporous Ag is obtained. • The substrate-supported nanoporous Ag exhibits excellent mechanical properties. The substrate-supported nanoporous Ag with controllable thickness and different morphologies (bulk-like and wire-like) is fabricated via the liquid Ga-assisted alloying/dealloying strategy. [Display omitted] Nanoporous metals show great potentials in various applications including catalysis, sensing, actuation and supercapacitors. The liquid Ga-assisted alloying/dealloying strategy is a feasible and scalable way to fabricate substrate-supported nanoporous metals. However, the influence of intrinsic alloying mode and mechanism on the formation and modulation of nanoporous structure has not been thoroughly explored before. In this work, after painting liquid Ga on Ag foil, both the bulk-like Ag 3 Ga (in the Ag-rich zone) and wire-like Ag 3 Ga (in the liquid Ga-rich zone) form owing to the interdiffusion of Ag and Ga atoms. Correspondingly, the bimodal wire-like and unimodal bulk-like nanoporous Ag is obtained because of the structure inheritance during dealloying. In addition, the thickness of alloy layer (nanoporous layer) versus mass loading of liquid Ga follows a good linear relationship. The in-situ X-ray diffraction of dealloying from Ag 3 Ga to nanoporous Ag illustrates no other intermetallic phase appears and the dealloying process can be described by the dissolution-surface diffusion model. More importantly, the substrate-supported nanoporous Ag exhibits excellent mechanical properties which are of great importance to the future applications of nanoporous metals. [ABSTRACT FROM AUTHOR]

The correlation between local structures and dynamics of the central Al atoms of the icosahedral clusters in the Al 90 Sm 10 super-cooled liquid was investigated by classic molecular dynamics simulations. Three typical order parameters (i.e. the chemical composition, cluster penetration, and quasi-nearest atom) of the Al-centered icosahedral clusters were calculated and we demonstrated that the correlation between each of these parameters and dynamic propensities of the central Al atoms of the icosahedral clusters is weak. Then a simple combined parameter including these three parameters was proposed and it is found that there is a strong correlation between this new parameter and dynamic propensities of the central Al atoms of the icosahedral clusters. The present observations imply that the dynamic property of icosahedral clusters was mainly determined by multiple structural features of local structures. Our results are helpful to understand the relationship between atomic structures and dynamics in super-cooled liquids. [ABSTRACT FROM AUTHOR]

Abstract: Atomic structure of Cu37Sb63 and Cu20Sb80 melts has been studied by high temperature X-ray diffraction and viscosity measurement. Split main peaks indicate Cu–Sb heterogeneous and Sb-homogeneous clusters dominate in these two melts, respectively. This results in the smaller first-neighbor radius and higher viscosity in Cu37Sb63 melts. In pair distribution functions of Cu20Sb80 melts, the hump around 0.44nm becomes obvious below 973K, which reveals the reinforcement of Sb clusters with Peierls distortion. This is consistent with the increase in viscous-flow activation energy in Cu20Sb80 melts around 973K. Structure parameters change is also discussed in terms of clusters evolution during cooling. [Copyright &y& Elsevier]

A facile structural refining for Sb film anode is firstly applied in SIBs by increasing the working pressure. Compared with Sb@0.2Pa and Sb@1Pa, the Sb@3Pa anode exhibits improved performance, stemming from its refined architecture. Surprisingly, the progressive in-situ electrochemically-driven Cu-Sb alloying can be probed upon cycling onward and further clarified by operando XRD, ex-situ SEM and DFT calculations. • A scalable structural refining for sputtered Sb film via altering working pressure. • The Sb@3Pa anode exhibits better performance owing to refined structure. • The (de)sodiation mechanism of Sb anodes was probed utilizing operando XRD. • In-situ electrochemically-driven Cu-Sb alloying is firstly observed in SIBs. Sb is a promising anode for sodium ion batteries (SIBs) but held back from practical application owing to its pulverization induced by dramatic volumetric variation. Herein, we propose a simple pressure-induced regulation strategy to efficiently refine nanoscale column-channel architecture of Sb layer by magnetron sputtering, which is easily manipulated and reproductive in practical conditions. The refining process under high working pressure can be ascribed to the synergistic effects from the shadow effect, the low kinetic energy of sputtered Sb atoms and high diffusion barrier on substrate. As benchmarked with Sb@0.2Pa and Sb@1Pa electrodes, the Sb@3Pa anode exhibits significantly enhanced electrochemical performance owing to structural refining effect generated by the elevated working pressure, effectively accelerating the ion/electron transfer and mitigating the volumetric variations. Notably, the progressive in-situ electrochemically-driven alloying in Sb layer on the Cu substrate to form Cu x Sb with the gradient Cu/Sb content is detected and further rationalized by operando XRD, ex-situ SEM and DFT calculations. Simultaneously, the formed Cu-Sb layer yields a novel (de)sodiation mechanism of Cu x Sb 1−x ↔ Na y Cu x Sb 1−x ↔ Na 3 Cu x Sb 1−x after the 1st discharge. [ABSTRACT FROM AUTHOR]

The low capacity of traditional graphite (372 mAh g−1) greatly limits its development as electrode material for future applications, and seeking new anode material is becoming extremely urgent in order to meet the increasing demands. In this work, flexible, self-supporting CuGa 2 films are fabricated by simply painting liquid Ga onto commercial Cu films, which can be used as electrodes directly after annealing. When the CuGa 2 films are applied as anodes in lithium ion batteries, higher capacity (more than 630 mAh g−1 at a current density of 200 mA g−1) and better rate performance (463.7 mAh g−1 at 4000 mA g−1) are achieved compared with those with pure Ga electrodes. Meanwhile, the lithiation-delithiation mechanism is detected by in-situ X-ray diffraction, and the alloying-dealloying processes (CuGa 2 + 2 x Li+ + 2 x e− ↔ Cu + 2Li x Ga) can be verified at the first and fourth cycles. The CuGa 2 anode shows excellent self-healing properties during cycling. Image 1 ∙ A simple, maneuverable method was developed to fabricate CuGa 2 films. ∙ The flexible, self-supporting CuGa 2 films can be used as anodes for LIBs directly. ∙ The CuGa 2 anode exhibits excellent electrochemical performance. ∙ The SEM and in-situ XRD verify the self-healing behaviors of the CuGa 2 anode. [ABSTRACT FROM AUTHOR]

The kinesin-5 family member, Eg5, plays very important role in the mitosis. As a mitotic protein, Eg5 is the target of various mitotic inhibitors. There are two targeting pockets in the motor domain of Eg5, which locates in the α2/L5/α3 region and the α4/α6 region respectively. We investigated the interactions between the different inhibitors and the two binding pockets of Eg5 by using all-atom molecular dynamics method. Combined the conformational analysis with the free-energy calculation, the binding patterns of inhibitors to the two binding pockets are shown. The α2/L5/α3 pocket can be divided into 4 regions. The structures and binding conformations of inhibitors in region 1 and 2 are highly conserved. The shape of α4/α6 pocket is alterable. The space of this pocket in ADP-binding state of Eg5 is larger than that in ADP·Pi-binding state due to the limitation of a hydrogen bond formed in the ADP·Pi-binding state. The results of this investigation provide the structural basis of the inhibitor-Eg5 interaction and offer a reference for the Eg5-targeted drug design., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Whether bisphenols, as plasticizers, can influence bacterial uptake of antibiotic resistance genes (ARGs) in natural environment, as well as the underlying mechanism remains largely unknown. Our results showed that four commonly used bisphenols (bisphenol A, S, F, and AF) at their environmental relative concentrations can significantly promote transmission of ARGs by 2.97-3.56 times in Acinetobacter baylyi ADP1. Intriguingly, we observed ADP1 acquired resistance by integrating plasmids uptake and cellular metabolic adaptations other than through reactive oxygen species mediated pathway. Metabolic adaptations including upregulation of capsules polysaccharide biosynthesis and intracellularly metabolic enzymes, which enabled formation of thicker capsules for capturing free plasmids, and degradation of accumulated compounds. Simultaneously, genes encoding DNA uptake and translocation machinery were incorporated to enhance natural transformation of antibiotic resistance carrying plasmids. We further exposed aquatic fish to bisphenols for 120 days to monitor their long-term effects in aquatic environment, which showed that intestinal bacteria communities were dominated by a drug resistant microbiome. Our study provides new insight into the mechanism of enhanced natural transformation of ARGs by bisphenols, and highlights the investigations for unexpectedly-elevated antibiotic-resistant risks by structurally related environmental chemicals., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Electrochemical CO 2 reduction (CO 2 ER) to formate is an attractive approach for CO 2 utilization. Here, we report a nanoporous bismuth (np-Bi) catalyst fabricated by chemically dealloying a rapidly solidified Mg 92 Bi 8 alloy for CO 2 ER. The np-Bi catalyst exhibits a three-dimensional interconnected ligament-channel network structure, which can efficiently convert CO 2 to formate with a selectivity of ≤94% and an activity of 62 mA cm -2 in a wide potential range. Remarkably, the np-Bi catalyst delivers an industry-level current density of ∼500 mA cm -2 for formate production at a low overpotential of 420 mV in the flow cell. The outstanding CO 2 ER performance can be attributed to the enlarged surface area with abundant accessible active sites and highly curved surfaces with enhanced intrinsic activity. This work highlights the structural synergies for enhancing CO 2 ER.

Facilitating the mass transfer and enlarging the active surface area are two mutually exclusive demands in porous materials, while structural hierarchy could settle this issue by constructing continuous channels with different length scales. However, it is a great challenge to fabricate porous metallic materials with three or more geometrically similar hierarchy levels. Herein, a novel strategy combining vapor phase dealloying with electrochemical dealloying is proposed to achieve nanoporous gold (NPG) with three-level nested hierarchy (N 3 PG), in which the length scale covers micron (5866.8 ± 1445.5 nm), submicron (509.9 ± 106.0 nm), and nanometer (20.1 ± 3.0 nm) for each level. Notably, the structural superiority of such material is manifested by its faster charge transfer behaviors, as benchmarked with unimodal and bimodal NPG (N 1 PG and N 2 PG). The present strategy is of great potential to fabricate other hierarchically porous metals with enhanced functional and structural properties., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)

Bisphenol S (BPS) is extensively used for production of polycarbonates and other commodities, and is often detected in environment and biota. Parental BPS exposure has been reported to interfere with reproductive development of offspring, but limited information is available on its multigenerational reproductive toxicity. In our present study, zebrafish (Danio rerio) were exposed to BPS (1 and 100 μg/L) from 3 hpf to 120 dpf, and the effects on reproduction, sex steroid hormones, DNA methylation levels and gene transcription involved in steroidogenesis and DNA methylation were investigated in unexposed F1-2 offspring. The results showed that 100 μg/L BPS exposure increased DNA methylation in F1 testes, and 1 μg/L BPS led to DNA methylation in F2 ovaries. The increased DNA methylation levels led to decreased expression of steroidogenic enzymes, including cyp11a, cyp17 and 3βhsd, which might be a main reason for the elevated plasma 17β-estradiol and decreased testosterone levels. In addition, sex ratio indicated a female dominance trend, and reproductive capacity of male fish was severely impaired. Overall, these findings suggest that parental BPS exposure impairs reproductive development of unexposed offspring via DNA methylation and BPS-induced epigenetic modification inheritance has a long-term effect on the fitness and sustainability of fish populations., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Understanding how topologically close-packed phases (TCPs) transform between one another is one of the challenging puzzles in solid-state transformations. Here we use atomic-resolved tools to dissect the transition among TCPs, specifically the μ and P (or σ) phases in nickel-based superalloys. We discover that the P phase originates from intrinsic (110) faulted twin boundaries (FTB), which according to first-principles calculations is of extraordinarily low energy. The FTB sets up a pathway for the diffusional in-flux of the smaller 3d transition metal species, creating a Frank interstitial dislocation loop. The climb of this dislocation, with an unusual Burgers vector that displaces neighboring atoms into the lattice positions of the product phase, accomplishes the structural transformation. Our findings reveal an intrinsic link among these seemingly unrelated TCP configurations, explain the role of internal lattice defects in facilitating the phase transition, and offer useful insight for alloy design that involves different complex phases., (© 2022. The Author(s).)

A novel one-step method to prepare the nanocomposites of reduced graphene oxide (RGO)/nanoporous gold (NPG) is realized by chemically dealloying an Al 2 Au precursor. The RGO nanosheets anchored on the surface of NPG have a cicada wing like shape and act as both conductive agent and buffer layer to improve the catalytic ability of NPG for methanol electro-oxidation reaction (MOR). This improvement can also be ascribed to the microstructure change of NPG in dealloying with RGO. This work inspires a facile and economic method to prepare the NPG based catalyst for MOR., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A composite was prepared at room temperature from nitrogen-doped reduced graphene oxide (N-rGO) and melamine via π-interaction. An ultra-sensitive electrochemical sensor for the determination of trace levels of bisphenol A (BPA) was obtained by coating a glassy carbon electrode (GCE) with the composite. The structure and morphology of composite were characterized by FTIR, Raman, XRD, XPS, SEM and TEM. Because of the synergetic effects of N-rGO and melamine, the modified GCE displays considerably enhanced sensitivity to BPA. The voltammetric response, typically measured at a peak of 0.48 V (vs. SCE) is linear in the 0.05 to 20 μM BPA concentration range, and the detection limit is 0.8 nM (at S/N = 3). The sensor is reproducible, stable and selective. It was applied to analyze baby bottles, drinking cups, mineral water bottles and shopping receipts that were spiked with BPA, and the recoveries reached 99.1-101.4%. Graphical abstract Illustration of fabricating the electrochemical sensor for detecting BPA. N-G/M: nitrogen-doped reduced graphene oxide and melamine composite; GCE: glassy carbon electrode.

The structural, magnetic, and electronic properties of Fe 82 Si 4 B 10 P 4 metallic glass were systemically investigated by theoretical simulations. Strong atomic interaction between Fe and metalloid atoms can be observed, while the direct metalloid-metalloid atomic bonds are rare due to the solute-solute avoidance effect. The calculated value of saturation magnetic flux density (B S ) is ~1.65 T, approaching to experimental result, which is contributed by not only the electron exchange between Fe and metalloid atoms, but also the p-d orbital hybridization of Fe atoms. Moreover, Fe atoms with neighboring P atom behaving larger magnetic moments reveals the important role of P element for promoting the B S value. The potential correlation between magnetic behaviors and the local atomic packing in this study sheds some light on the structural origin of the soft magnetic properties and, thereby the theoretical guidance for the development of new soft-magnetic metallic glasses.