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Graphene oxide-derived single-atom catalysts for electrochemical energy conversion

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Rare Metals 2022年第5期41卷 1703-1726页

作者： jian-Bin Liu Hai-Sheng gong gong-Lan Ye Hui-Long Fei State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Sustainable electrochemical energy conversion is considered as a promising solution to energy crises and environmental issues. Owing to their maximized utilization efficiency and excellent catalytic performance, single-atom catalysts(SACs) have obtained tremendous attention in the field of electrochemical energy conversion. In the last few years, graphene oxide(GO) has been considered to be a promising precursor for fabricating graphene-supported SACs due to its advantageous features such as large surface area, high density of intrinsic defects, and scalability. In this review, the recent advances in the preparation of graphene oxide-derived single-atom catalysts(GO-SACs) and their diverse electrochemical applications are ***, the synthetic strategies of GO-SACs are discussed with focuses on the advantages and shortages of each method. Subsequently, the electrochemical applications of GO-SACs in various energy conversion processes,including the oxygen reduction reaction(ORR), oxygen evolution reaction(OER), hydrogen evolution reaction(HER), nitrogen reduction reaction(NRR), and carbon dioxide reduction reaction(CO;RR), are discussed in detail. Finally, the remaining challenges and future prospects in the fabrication and application of GO-SACs are presented.

关键词： Single-atom catalysts Graphene oxide Electrocatalysis Energy conversion

Effect of local non-convexity on the critical shear strength of granular materials determined via the discrete element method

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Particuology 2020年第5期18卷 105-112页

作者： Zhihong Nie Shunkai Liu Wei Hu jian gong School of Civil Engineering Central South UniversityChangshaHunan 410075China Hunan Province Key Laboratory of Geotechnical Engineering Stability Control and Health Monitoring Hunan University of Science and TechnologyXiangtanHunan 411201China School of Hydraulic Engineering Changsha University of Science and Technology Changsha 410114China

Multi-sphere clumps are commonly used to simulate non-spherical particles in discrete element method *** is of interest whether the degree of local non-convexity λ affects the mechanical behaviour of granular materials with the same non-convexity η.A series of discrete-element-method biaxial shear tests are conducted on rough particle packings with rη=0.075 and different λ values(ranging from 0.134 to 0.770).The microscale results show that the contact type changes with an increase in λ.However,the critical strength is independent of λ.The evaluation of the contributions of different contact types to the critical shear strength and a detailed analysis of the anisotropies help clarify the microscopic mechanisms that result in the independence of the critical shear strength from λ.

关键词： Multi-sphere clump Local non-convexity Discrete element method Biaxial shear test Contact type Critical shear strength

Antiviral stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-1,2,4-thiadiazole from the roots of Isatis indigotica

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Chinese Chemical Letters 2016年第5期27卷 643-648页

作者： Ming-Hua Chen Sheng Lin Ya-Nan Wang Cheng-Gen Zhu Yu-Huan Li jian-dong jiang jian-gong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College

Four stereoisomers of 3,5-bis（2-hydroxybut-3-en-1-yl）-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D （1a-1d）, were isolated from the roots oflsatis indigotica. Their structures were determined by spectroscopic analysis; specifically, the absolute configurations were assigned by using the MPA determination rule based on △δrs values of MPA esters, and supported by electronic CD （ECD） calculations. Proposed biosynthetic pathways and preliminary investigations of the biological activities of la-1d against influenza virus A （H3N2）, Coxsackie virus B3, and/or HSV-1 are also discussed.

关键词： Isatis indigoticaCruciferae3.5-Bis( 2-hydroxybut-3-en- 1 -yl)-1 2 4-thiadiazole Stereoisomer Insatindigothiadiazoles A-DAntiviral activity

Tetraolefin stereospecific photodimerization and photopolymerization in coordination polymers

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Science China Chemistry 2022年第10期65卷 1867-1872页

作者： Wei-Jie gong Zhan-Yong Yang Yu-Xuan Hong dong Liu Zheng Niu Pierre Braunstein jian-Ping Lang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials School of Chemistry and Chemical EngineeringHuaiyin Normal UniversityHuaian 223300China Universitéde Strasbourg-CNRS Institut de Chimie(UMR 7177 CNRS)4 rue Blaise Pascal-CS 90032Strasbourg 67081France

In the context of the highly desirable design and preparation of smart materials with adjustable properties based on photoreactive compounds,we report two unique photoreactive coordination polymers(CPs),{[Zn(4-Iba)_(2)(4-tkpvb)]·H_()2O}_(n)(1,4-HIba=4-iodobenzoic acid,4-tkpvb=1,2,4,5-tetrakis(4-pyridylvinyl)benzene)and[Cd(1,4-bdc)(4-tkpvb)]_(n)(2,1,4-H_(2)bdc=1,4-benzenedicarboxylic acid).Depending on the metal ions and auxiliary carboxylate ligands used,the 4-tkpvb ligands in 1 and 2 adopt different mutual arrangements,which facilitate the photodimerization and photopolymerization reactions in single crystal to single crystal(SCSC)*** UV light irradiation which results in the dimerization of the 4-tkpvb ligands,the one-dimensional(1D)zigzag chainsof 1 are transformed into a two-dimensional(2D)network of{[Zn(4-Iba)_(2)(bpbtpvcb)_(0.5)]·H_(2)O}_(n)(1a,bpbtpvcb=1,3-bis(4-pyridyl)-2,4-bis(2,4,5-tri(2-(4-pyridyl)vinyl)phenylcyclobutane).Similarly,in the crystals of 2,all 4-tkpvb ligands experience a photopolymerization reaction to form an unprecedented 1D linear organic polymer,poly-1,3-bis(4-pyridyl)-2,5-bis(2-(4-pyridyl)-vinyl)phenyl)cyclobutane(poly-bpbpvpcb).Furthermore,the 2D network of 2 is converted into a three-dimensional(3D)framework of[Cd_(n)(1,4-bdc)_(n)(poly-bpbpvpcb)](2a).This work not only offers a new protocol to selectively synthesize new supramolecular cyclic compounds,but also expands the application of photopolymerization to the synthesis of macromolecules.

关键词： coordination polymers single-crystal to single-crystal transformation photodimerization photopolymerization cycloaddition

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Architecture design for reliable and reconfigurable FPGA-based GNC computer for deep space exploration

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Science China(Technological Sciences) 2016年第2期59卷 289-300页

作者： YANG MengFei LIU Bo gong jian LIU HongJin HU HongKai dong YangYang SHI Lei ZHAO YunFu MIAO ZhiFu China Academy of Space Technology Beijing 100094 China Beijing Institute of Control Engineering Beijing 100190 China

SRAM(static random access memory)-based FPGA(field programmable gate array), owing to its large capacity, high performance, and dynamical reconfiguration, has become an attractive platform for So PC(system on programmable chip) development. However, as the configuration memory and logic memory of the SRAM-based FPGA are highly susceptible to SEUs(single-event upsets) in deep space, it is a challenge to design and implement a highly reliable FPGA-based system for spacecraft, and no practical architecture has been proposed. In this paper, a new architecture for a reliable and reconfigurable FPGAbased computer in a highly critical GNC(guidance navigation and control) system is proposed. To mitigate the effect of an SEU on the system, multi-layer reconfiguration and multi-layer TMR(triple module redundancy) techniques are proposed, with a reliable reconfigurable real-time operating system(Space OS) managing the system level fault tolerance of the computer in the architecture. The proposed architecture for the reconfigurable FPGA-based computer has been implemented with COTS(commercial off the shelf) FPGA and has firstly been applied to the GNC system of a circumlunar return and reentry flight vehicle. The in-orbit results show that the proposed architecture is capable of meeting the requirements of high reliability and high availability, and can provide the expressive varying functionality and runtime flexibility for an FPGA-based GNC computer in deep space.

关键词： fault tolerance system on programmable chip (SoPC) field programmable gate array (FPGA) multi-layer triple mod-ule redundancy intelligence reconfiguration

Phase Selection and Microstructure Evolution Dependance on Composition for Zr-Fe Eutectic Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第10期37卷 1689-1702页

作者： dong-dong Zuo jian Chang Hai-Peng Wang School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an710072China

The knowledge of the phase selection and microstructure evolution of Zr-Fe eutectic alloys is still poorly *** presumed eutectic alloy with a nominal composition of Zr76.0Fe24.0 was discovered to contain a significant proportion ofα-Zr ***,phase selection and microstructure evolution dependance on composition for Zr-Fe eutectic alloys was experimentally determined by using differential scanning calorimetry(DSC)and meticulous electron *** alloys,spanning the composition range of 73.5-74.7%Zr,were examined to investigate microstructure evolution and non-isothermal crystallization *** indicate that in alloys ranging from Zr_(73.5)Fe_(26.5) to Zr_(73.9)Fe_(26.1),the primary FeZr_(2) phase demonstrates preferential growth,followed by eutectic microstructure formation during liquid alloy *** volume fraction of FeZr_(2) dendrites decreases as the Zr content ***,in alloys ranging from Zr_(74.0)Fe_(26.0) to Zr_(74.7)Fe_(25.3),primaryβ-Zr dendrites preferentially grow,followed by a eutectic reaction in the remaining liquid *** content ofα-Zr dendrites reduces with decreasing Zr *** mentioned above,a critical composition range for phase selection is defined as Zr_(x)Fe100.0−x(73.9

关键词： Phase selection Thermal analysis Microstructure evolution Crystallization kinetic

The effect of wind on the dispersal of a tropical small river plume

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Frontiers of Earth Science 2018年第1期12卷 170-190页

作者： Junpeng ZHAO Wenping gong jian SHEN School of Marine Sciences Sun Yat-Sen University Guangzhou 510275 China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering Sun Yat-Sen University Guangzhou 510275 China Virginia Institute of Marine Science The College of William and Mary Gloucester Point VA 23062 USA

Wanquan River is a small river located in Hainan, a tropical island in China. As the third largest river in Hainan, the river plume plays an important role in the regional terrigenous mass transport, coastal circulation, and the coral reef＇s ecosystem. Studies have shown that wind forcings significantly influence river plume dynamics. In this study, wind effects on the dispersal of the river plume and freshwater transport were examined numerically using a calibrated, unstructured, finite volume numerical model （FVCOM）. Both wind direction and magnitude were determined to influence plume dispersal. Northeasterly （downwelling-favorable） winds drove fresh- water down-shelf while southeasterly （onshore） winds drove water up-shelf （in the sense of Kelvin wave propagation） , and were confined near the coast. Southwesterly （upwelling-favorable） and northwesterly （off： shore） winds transport more freshwater offshore. The transport flux is decomposed into an advection, a vertical shear, and an oscillatory component. The advection flux dominates the freshwater transport in the coastal area and the vertical shear flux is dominant in the offshore area. For the upwelling-favorable wind, the freshwater transport becomes more controlled by the advection transport with an increase in wind stress, due to enhanced vertical mixing. The relative importance of wind forcing and buoyancy force was investigated. It was found that, when the Wedderburn number is larger than one, the plume was dominated by wind forcing, although the importance of wind varies in different parts of the plume. The water column stratification decreased as a whole under the prevailing southwesterly wind, with the exception of the up-shelf and offshore areas.

关键词： small river plume wind effect freshwater transport

An Improved Result for Positive Measure Reducibility of Quasi-periodic Linear Systems

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Acta Mathematica Sinica,English Series 2006年第1期22卷 77-86页

作者： Hai Long HE jian gong YOU Department of Mathcmatics Nanjing University Nanjing 210093 P. R. China

In this paper, by the KAM method, under weaker small denominator conditions and nondegeneracy conditions, we prove a positive measure reducibility for quasi-periodic linear systems close to constant： X = （A（λ）＋ F（ψ, λ））X, ψ=ωwhere the parameter λ∈ （a, b）, w is a fixed Diophantine vector, which is a generalization of jorba ＆ Simo＇s positive measure reducibility result.

关键词： Quasi-periodic Reducibility KAM Non-degeneracy

Quantum key distribution protocol of mesh network structure based on n+1 EPR pairs

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Journal of Systems Engineering and Electronics 2010年第2期21卷 334-338页

作者： jian dong jianfu Teng School of Electronic Information Engineering Tianjin University Tianjin 300072 P. R. China

Quantum key distribution （QKD） is used in quantum cryptographic systems to exchange secret key between parties who need to communicate secretly. According to the structure of European Secoqc QKD network, a QKD protocol is proposed. Entanglement swapping between Einstein-Podolsky-Rosen （EPR） pairs can be used to exchange message bits in two remote places. Based on this idea, n ＋ 1 EPR pairs are used as logical quan- tum channel （for n nodes per routing）, while measurements of Bell operator are transmitted by classical channel. Random space quantum channel selection is exploited in our protocol to improve the probability of revealing Eve. Compared with traditional EPR protocol, the proposed protocol exhibits many features, which are minutely described.

关键词： quantum cryptography quantum key distribution (QKD) EPR pair quantum entanglement entanglement swapping.