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Implementing a sidechain-based asynchronous DPKI

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Frontiers of Computer Science 2022年第1期16卷 195-197页

作者： Ziyuan LI Huimei WANG jian LIU Ming xian College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China

1 Introduction Public key infrastructure(PKI)is an integral part of the network communication *** on the certificate authority,it provides security policies for the systems,which enables users to communicate or conduct e-commerce transactions in a trustworthy *** PKI(CPKI)has been providing the netizens with security services and maintaining the privacy for decades.

关键词： services enable network

Folding of multi-layer graphene sheets induced by van der Waals interaction

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Acta Mechanica Sinica 2014年第3期30卷 410-417页

作者： xian-Hong Meng Ming Li Zhan Kang jian-Liang Xiao School of Aeronautic Science and Engineering Beihang University State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Department of Mechanical Engineering University of Colorado

Graphene sheets are extremely flexible, and thus small forces, such as van der Waals interaction, can induce significant out-of-plane deformation, such as folding. Folded graphene sheets show racket shaped edges, which can significantly affect the electrical properties of graphene. In this paper, we present combined theoretical and computational studies to reveal the folding behavior of multi-layer graphene sheets. A nonlinear theoretical model is established to determine the critical length of multilayer graphene sheets for metastable and stable folding, and to accurately predict the shapes of folded edges. These results all show good agree- ment with those obtained by molecular dynamics simulations.

关键词： Graphene Folding Stability Theoreticalmodel Molecular dynamics simulation

Use of liquid crystal to study the interactions of alkyl polyglycosides with gelatin and bovine serum albumin

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Chinese Chemical Letters 2016年第6期27卷 852-856页

作者： Zhi-jian Liao Si-Nan Du Yang luo Fang Zuo jian-Bin luo College of Chemistry & Environment Protection Engineering Southwest University for Nationalities

In this study, liquid crystal（LC） was used to study the interactions of alkyl polyglycosides（APG） with gelatin and bovine serum albumin（BSA） at the LC-aqueous interface. The LC easily undergo an orientational transition from a homeotropic to a planar state after proteins were in contact to the LCaqueous interface decorated with APG, thus inducing an optical change from dark to bright. The optical image analysis reveals that the rearrangement rate of APG monolayer is tightly dependent on the concentration and chemical structure of the protein of interest. For example, the rearrangement rate of APG monolayer increases with an increasing gelatin concentration. We also find that the chemical structure of the proteins has a significant impact on the difference in the growth behavior of bright domains in LC.

关键词： Liquid crystal Alkyl polyglycoside Optical image Orientational transition

Laboratory-scale investigation of the material distribution characteristics of landslide dams in U-shaped valleys

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Journal of Mountain Science 2023年第3期20卷 688-704页

作者： jian Fu-xian CAI Zheng-yin GUO Wan-li Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210024China

Material distribution characteristics during sliding and depositing is particularly significative to investigate the internal structure and spatial variation of landslide dams,which are fundamentally determining the mechanical and hydraulic behavior and the susceptibility to cause dam ***,limited by longevity shortages and special geographic environments,the material distribution characteristics and their formation mechanisms are difficult to observe in the ***,an experimental apparatus modeling a landslide dam was developed in this paper,designing three sampling methods with two valley *** internal deposit characteristics,void ratio variation and relative content of the particle size range(PSR)were analyzed,and the mechanics of deposit structure were also delicately *** results indicate that granular material deposited in valley shows a structure of inverse grain size accumulation in both vertical and horizontal directions,exhibiting spatial variability of particle gradation and void *** characteristic PSR decreases from 22-30 mm in the two-dimensional state to 10-14 mm in the threedimensional *** excitation and vibration sieve are the intrinsic mechanisms of granular flow segregation,intrinsically inducing the formation of inverse grading deposit ***,spatial variability in size is mainly trig gered by segregation,whereas coarse particle content and deposition boundaries merely exacerbate the difference degree.

关键词： Landslide dam IInverse grading structure Granular flow segregation Material spatial variability Deposit characteristics

C/Ti/Cu interfacial reaction in SiCf/Cu composites

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Rare Metals 2011年第4期30卷 396-400页

作者： luo xian YANG Yanqing WANG Chen LOU Juhong XUE Chunling State Key Laboratory of Solidification Processing School of Materials Science Northwestern Polytechnical University Xi＇an 710072 China

Continuous SiC fiber reinforced copper matrix （SiC~/Cu） composites were prepared by fiber coating method, and Ti6A14V interlayer was introduced as an interfacial modification coating to improve the interfacial bonding strength. The interfacial reaction characteristics were investigated by transmission electron microscopy （TEM）. The results show that nearly all the titanium atoms reacted with the carbon coating of SiC fibers to form two layers of TiC. Also, a thin copper layer that is sandwiched between these two layers was detected. No Ti-Cu interfacial reaction product was observed. The formation process of the interfacial reaction along with its mechanism was discussed.

关键词： metallic matrix composite copper interfacial reactions silicon carbide fibers

Efficient Location-Aware Data Placement for Data-Intensive Applications in Geo-distributed Scientific Data Centers

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Tsinghua Science and Technology 2016年第5期21卷 471-481页

作者： Jinghui Zhang jian Chen Junzhou luo Aibo Song School of Computer Science and Engineering Southeast University Nanjing 211189 China

Recent developments in cloud computing and big data have spurred the emergence of data-intensive applications for which massive scientific datasets are stored in globally distributed scientific data centers that have a high frequency of data access by scientists worldwide. Multiple associated data items distributed in different scientific data centers may be requested for one data processing task, and data placement decisions must respect the storage capacity limits of the scientific data centers. Therefore, the optimization of data access cost in the placement of data items in globally distributed scientific data centers has become an increasingly important *** data placement approaches for geo-distributed data items are insufficient because they either cannot cope with the cost incurred by the associated data access, or they overlook storage capacity limitations, which are a very practical constraint of scientific data centers. In this paper, inspired by applications in the field of high energy physics, we propose an integer-programming-based data placement model that addresses the above challenges as a Non-deterministic Polynomial-time（NP）-hard problem. In addition we use a Lagrangian relaxation based heuristics algorithm to obtain ideal data placement solutions. Our simulation results demonstrate that our algorithm is effective and significantly reduces overall data access cost.

关键词： data placement geo-distributed data center Lagrangian relaxation

Quasicrystal dissolution and performance of isothermally heat-treated Mg–Zn–Y alloy

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Rare Metals 2015年第7期34卷 452-456页

作者： Di-Qing Wan xian luo Ya-Juan Liu Tian Yu Key Laboratory of Ministry of Education for Conveyance and Equipment East China Jiaotong University State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science Northwestern Polytechnical University

Conventional casting method was employed to prepare Mg–Zn–Y alloy only with a-Mg+I-phase; however, the grain size of quasicrystal is quite large in the ascast ***, isothermal treatment was applied to refine the quasicrystal *** result shows that after the Mg–Zn–Y alloy was isothermally treated at 500 °C for several hours, the coarse quasicrystal can be gradually dissolved and thus ***, the dissolving processes of quasicrystal are slow first and then accelerate;after isothermally treated with 8 h at 500 °C, the quasicrystal is almost completely dissolved into the matrix only with 1–5 lm tiny quasicrystals *** of quasicrystal can markedly reduce the wear resistance, but increase the corrosion resistance.

关键词： Magnesium alloy Quasicrystal Isothermal treatment

Copper-based metal-organic frameworks for electrochemical reduction of CO_(2)

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Chinese Chemical Letters 2023年第6期34卷 111-120页

作者： Xiaomin Kang Guodong Fu xian-Zhu Fu Jing-Li luo Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China School of Mechanical Engineering University of South ChinaHengyang 421001China

The electrochemical CO_(2)reduction reaction(CO_(2)ER)is an emerging process that involves utilizing CO_(2)to produce valuable chemicals and fuels by consuming excess electricity from renewable ***,Cu and Cu-based nanoparticles,as earth-abundant and economical metal sources,have been attracting significant *** chemical and physical properties of Cu-based nanoparticles are modified by different strategies,and CO_(2)can be converted into multicarbon *** various Cu-based nanoparticles,Cu-based metal-organic frameworks(MOFs)are gaining increasing interest in the field of catalysis because of their textural,topological,and electrocatalytic *** this minireview,we summarized and highlighted the main achievements in the research on Cu-based MOFs and their advantages in the CO_(2)ER as electrocatalysts,supports,or precursors.

关键词： CO_(2)electrochemical reduction Cu nanoparticles Cu-based MOFs Electrocatalysts Electrochemical reduction reaction

Computing grain boundary diagrams of thermodynamic and mechanical properties

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npj Computational Materials 2021年第1期7卷 1442-1453页

作者： Chongze Hu Yanwen Li Zhiyang Yu jian luo Department of Nanoengineering University of California San DiegoLa JollaCA 92093USA Program of Materials Science and Engineering University of California San DiegoLa JollaCA 92093USA State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou University350002 FuzhouFujianP.R.China Department of Physics Southern University of Science and TechnologyShenzhenGuangdong 518055P.R.China

Computing the grain boundary(GB)counterparts to bulk phase diagrams represents an emerging research *** a classical embrittlement model system Ga-doped Al alloy,this study demonstrates the feasibility of computing temperature-and composition-dependent GB diagrams to represent not only equilibrium thermodynamic and structural characters,but also mechanical ***,hybrid Monte Carlo and molecular dynamics(MC/MD)simulations are used to obtain the equilibrium GB structure as a function of temperature and *** GB structures are validated by aberrationcorrected scanning transmission electron ***,MD tensile tests are performed on the simulated equilibrium GB *** diagrams are computed for not only GB adsorption and structural disorder,but also interfacial structural and chemical widths,MD ultimate tensile strength,and MD tensile *** study suggests a research direction to investigate GB composition–structure–property relationships via computing GB diagrams of thermodynamic,structural,and mechanical(or potentially other)properties.

关键词： grain toughness alloy