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Covalent electron density analysis and surface energy calculation of gold with the empirical electron surface model

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 676-682页

作者： Bao-qin fu Zhi-lin Li Wei Liu College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Laboratory of Advanced Materials Department of Material Science and Engineering Tsinghua University Beijing 100084 China

Based on the empirical electron surface model （EESM）,the covalent electron density of dangling bonds （CEDDB） was calculated for various crystal planes of gold,and the surface energy was calculated *** results show that CEDDB has a great influence on the surface energy of various index surfaces and the anisotropy of the *** calculated surface energy is in agreement with experimental and other theoretical *** calculated surface energy of the close-packed （111） surface has the lowest surface energy,which agrees with the theoretical ***,it is found that the spatial distribution of covalent bonds has a great influence on the surface energy of various index ***,CEDDB should be a suitable parameter to describe and quantify the dangling bonds and surface energy of various crystal surfaces.

关键词： surface energy dangling bonds covalent bonds electron density gold

Synthesis and Crystal Structure of 3-(2-Hydroxybenzly)-4-(4-Hydroxybenzylideneamino)-(1H) -1,2,4-Triazole-5-Thione and Its Antibacterial Activities

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1403-1407页

作者： YANG jian-Guo PAN fu-You Office of Assets Administration Taizhou University Zhejiang 317000 China Department of Chemistry Taizhou University Zhejiang 317000 China

The title compound C15H12N4O2S was synthesized by the reaction of 3-（2-hydroxybenzyl）-4-amino-（1H）-1,2,4-triazole-5-thione with 4-hydroxybenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and elemental analysis. Its structure has been determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group C2/c with a = 27.990（3）, b = 13.1326（14）, c = 7.9770（8） A, β= 105.787（2）°, V = 2821.6（5）A^3, Z = 8, Mr= 312.35,μ= 0.243 mm^-1, Dc = 1.471 g/cm^3 and F（000） = 1296. The structure was solved by direct *** refined to a Rint value of 0.0388. The crystal structure involving in intermolecular N-H…S and O-H…S hydrogen bonds is observed, meanwhile intramolecular O-H…N hydrogen bond is also found. Their biological activities have been measured. The results show that this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis.

关键词： 1,2,4-triazole-5-thione X-ray diffraction crystal structure,synthesis antibacterial activities

Integrated HI emission in galaxy groups and clusters

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Research in Astronomy and Astrophysics 2017年第10期17卷 15-26页

作者： Mei Ai Ming Zhu jian fu National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

The integrated HI emission from hierarchical structures such as groups and clusters of galax- ies can be detected by FAST at intermediate redshifts. Here we propose to use FAST to study the evolution of the global HI content of clusters and groups over cosmic time by measuring their integrated HI emissions. We use the Virgo Cluster as an example to estimate the detection limit of FAST, and have estimated the integration time to detect a Virgo type cluster at different redshifts （from z = 0.1 to z ---- 1.5）. We have also employed a semi-analytic model （SAM） to simulate the evolution of HI contents in galaxy clusters. Our simulations suggest that the HI mass of a Virgo-like cluster could be 2-3 times higher and the physical size could be more than 50% smaller when redshift increases from z = 0.3 to z = 1. Thus the integration time could be reduced significantly and gas rich clusters at intermediate redshifts can be detected by FAST in less than 2 hours of integration time. For the local Universe, we have also used SAM simulations to create mock catalogs of clusters to predict the outcomes from FAST all sky surveys. Comparing with the optically selected catalogs derived by cross matching the galaxy catalogs from the SDSS survey and the ALFALFA survey, we find that the HI mass distribution of the mock catalog with 20 s of integration time agrees well with that of observations. However, the mock catalog with 120 s of integration time predicts many more groups and clusters that contain a population of low mass HI galaxies not detected by the ALFALFA survey. A future deep HI blind sky survey with FAST would be able to test such prediction and set constraints on the numerical simulation models. The observational strategy and sample selections for future FAST observations of galaxy clusters at high redshifts are also discussed.

关键词： galaxy clusters -- neutral hydrogen (HI) -- galaxy evolution

Metallic Sb-stabilized porous silicon with stable SEI and high electron/ion conductivity boosting lithium-ion storage performance

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Rare Metals 2024年第9期43卷 4234-4242页

作者： Jia-Guo Deng Hao-qin Feng Yu-Long Xu Si-Guang Guo jian-Ping Li Kai-fu Huo Ji-jiang fu Biao Gao Pual-K.Chu The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081China Wuhan National Laboratory for Optoelectronics(WNLO) School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China Department of Physics Department of Materials Science&Engineeringand Department of Biomedical EngineeringCity University of Hong KongHong Kong 999077China

Silicon(Si)has mild discharge potential and high theoretical capacity,making it a highly desirable material for lithium-ion batteries(LIBs).Nevertheless,the excessive volume expansion,poor ion/electron conductiv ity and unstable solid electrolyte interface(SEI)hinde practical application to ***,the metallic antimony(Sb)stabilized porous Si(SiDSb)composite was prepared by magnesiothermic reduction of Sb_(2)O_(3)and Mg_(2)Si and chemical etching to remove the by-product of *** highly conductive Sb nanodots embedded in the Si liga ments promote not only the formation of conductive and stable LiF-rich SEI,but also the electron/ion transpor ability of *** to the outstanding bulk/interface stability,excellent conductivity,as well as ideal porous structure,the SiDSb electrode demonstrates a capacity of820 mAh·g^(-1)after undergoing 320 turns at 1000 mA·g^(-1).Additionally,it exhibits a stable capacity of 675 m Ah·g^(-1)when tested at a higher current density of 5000 m A·g^(-1).The results reveal a viable solution to solve three problems at the same time,namely the poor conductivity,inferior SEI and excessive volume expansion of Si,boding well for the design of Si-based materials for high-energy LIBs.

关键词： Silicon Anodes Lithium-ion batteries Antimony Solid electrolyte interphase

Perturbation of the Moore–Penrose Metric Generalized Inverse in Reflexive Strictly Convex Banach Spaces

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Acta Mathematica Sinica,English Series 2016年第6期32卷 725-735页

作者： jian Bing CAO Wan qin ZHANG Postdoctoral Research Base He'nan Institute of Science and Technology Postdoctoral Research Station of Physics He'nan Normal University Department of Mathematics He'nan Institute of Science and Technology

Let X, Y be reflexive strictly convex Banach spaces, let T, δT ： X → Y be bounded linear operators with closed range R（T）. Put T= T ＋ δT. In this paper, by using the concept of quasiadditivity and the so called generalized Neumman lemma, we will give some error estimates of the bounds of ｜｜T^M｜｜. By using a relation between the concepts of the reduced minimum module and the gap of two subspaces, some new existence characterization of the Moore-Penrose metric generalized inverse T^M of the perturbed operator T will be also given.

关键词： Metric generalized inverse perturbation reflexive strictly convex Banach space

Design of new format for mass data compression

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 121-128页

作者： qin jian-cheng BAI Zhong-ying School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 China

In the field of lossless compression, most kinds of traditional software have some shortages when they face the mass data. Their compressing abilities are limited by the data window size and the compressing format design. This paper presents a new design of compressing format named ＇CZ format＇ which supports the data window size up to 4 GB and has some advantages in the mass data compression. Using this format, a compressing shareware named ＇ComZip＇ is designed. The experiment results support that ComZip has better compression ratio than WinZip, Bzip2 and are compressed. And ComZip has the potential to beat 7-zip in WinRAR in most cases, especially when GBs or TBs of mass data future as the data window size exceeds 128 MB.

关键词： mass data coding tossless compression LZ77/LZSS algorithm arithmetic coding

Syntheses and Crystal Structures of Co(Ⅱ)Complexes with 5-Tert-butyl Isophthalic Acid

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1108-1114页

作者： qin jian-Hua JU Feng-Yang College of Chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022 China

Two new Co（ Ⅱ） coordination polymers {[Co（Htbip）2（H2O）4]·（H2O）}n 1 and {[Co2（tbip）2Copa）1.5]（H2tbip）}n 2 （H2tbip = 5-tert-butyl isophtha]ic acid, bpa = 1,2-dis（4-pyri- dyl）ethane） have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy and X-ray diffraction. Compound 1 exhibits a water-bridged 1-D linear chain which is extended by hydrogen bonds into a 3D supramolecular network, while compound 2 has a dinuclear unit extended by bpa ligand to form a 2-D layer.

关键词： Co(Ⅱ) complex 5-tert-butyl isophthalic acid crystal structure

Analysis of Stealthy False Data Injection Attacks Against Networked Control Systems:Three Case Studies

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Journal of Systems Science & Complexity 2023年第4期36卷 1407-1422页

作者： PANG Zhonghua fu Yuan GUO Haibin SUN jian Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of TechnologyBeijing 100144China National Key Laboratory of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

This paper mainly investigates the security problem of a networked control system based on a Kalman filter.A false data injection attack scheme is proposed to only tamper the measurement output,and its stealthiness and effects on system performance are analyzed under three cases of system knowledge held by an attacker and a ***,it is derived that the proposed attack scheme is stealthy for a residual-based detector when the attacker and the defender hold the same accurate system ***,it is proven that the proposed attack scheme is still stealthy even if the defender actively modifies the Kalman filter gain so as to make it different from that of the ***,the stealthiness condition of the proposed attack scheme based on an inaccurate model is ***,for each case,the instability conditions of the closed-loop system under attack are ***,simulation results are provided to test the proposed attack scheme.

关键词： False data injection attack networked control systems(NCSs) stability stealthiness

Study on the effect of thermal deformation on the liquid seal of high-temperature molten salt pump in molten salt reactor

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Nuclear Science and Techniques 2023年第2期34卷 128-138页

作者： Xing‑Chao Shen Yuan fu jian‑Yu Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The high-temperature molten salt pump is the core equipment in a molten salt reactor that drives the flow of the molten salt *** stability is key to the continuous and reliable operation of the molten salt pump,and the liquid seal at the wear ring can affect the dynamic characteristics of the rotor *** the molten salt pump is operated in the hightemperature molten salt medium,thermal deformation of the submerged parts inevitably occurs,changing clearance between the stator and rotor,affecting the leakage and dynamic characteristics of the *** this study,the seal leakage,seal dynamic characteristics,and rotor system dynamic characteristics are simulated and analyzed using finite element simulation software based on two cases of considering the effect of seal thermal deformation effect or *** results show a significant difference in the leakage characteristics and dynamic characteristics of the seal obtained by considering the effect of seal thermal deformation and neglecting the effect of thermal *** leakage flow rate decreases,and the first-order critical speed of the seal-bearing-rotor system decrease after considering the seal’s thermal deformation.

关键词： High-temperature molten salt pump Seal thermal deformation Leakage characteristics Seal dynamic characteristics Critical speed