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Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science china chemistry 2025年第01期 186-191页

作者： Hai Zou Yunfeng Bao Xueshang Xin Yu Qi Tengfeng xie Fuxiang Zhang State Key Laboratory of catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of chemistry and chemical Engineering Liaoning Normal University college of chemistry Jilin University

constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

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Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of minerals,metallurgy and materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia xie chengjia Shang collaborative Innovation center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced metals and materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of minerals,metallurgy and materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced metals and materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)materials Sci.&Tech.co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HcP)structure to a high-entropy hydride with an faced-centered-cubic(Fcc)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/m(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/m was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/m ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science china chemistry 2025年第1期 249-256页

作者： Qing-Yun Fang chengyihan Gu Yinghan chen Wencheng Yan Yong Liang Weipeng Li chengjian Zhu Jie Han Jin xie State Key Laboratory of coordination chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green catalysis center College of Chemistry Zhengzhou University State Key Laboratory of Natural medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-c(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke xie meng XIA Huarong cHENG Anyu LIU Yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications chongqing Key Laboratory of Autonomous Navigation and microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

making sense of spike D614G in SARS-coV-2 transmission

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Science china(Life Sciences) 2021年第7期64卷 1062-1067页

作者： Aria c.Shi Xuping xie School of medicine Johns Hopkins UniversityBaltimoreMD 21205USA Department of Biochemistry and molecular Biology University of Texas Medical BranchGalvestonTX 77550USA

Severe acute respiratory syndrome coronavirus 2(SARS-coV-2),the etiologic agent of the current coronavirus disease 2019(cOVID-19)pandemic,has evolved to adapt to human host and transmission over the past 12 *** prominent adaptive mutation is the asparagine-to-glycine substitution at amino acid position 614 in the viral spike protein(D614G),which has become dominant in the currently circulating virus *** spike protein determines host ranges,tissue tropism,and pathogenesis through binding to the cellular receptor of angiotensin converting enzyme 2(AcE2),the D614G mutation is hypothesized to enhance viral fitness in human host,leading to increased transmission during the global *** we summarize the recent progress on the role of the D614G mutation in viral replication,pathogenesis,transmission,and vaccine and therapeutic antibody *** findings underscore the importance in closely monitoring viral evolution and defining their functions to ensure countermeasure efficacy against newly emerging variants.

关键词： SARS-coV-2 D614G cOVID-19

Optimal coordination of Transportable Power Sources and Repair crews for Service Restoration of Distribution Networks considering Uncertainty of Traffic congestion

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Journal of modern Power Systems and clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi Yan Xu Dunjian xie Shiwei xie Amer m.Y.m.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(Rcs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and Rcs is proposed,where the TPSs serve as emergency power supply sources,and the Rcs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(mILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program