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Electron microscopy studies of the coronavirus ribonucleoprotein complex

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Protein & Cell 2017年第3期8卷 219-224页

作者： gui, Miao Liu, Xin Guo, Deyin Zhang, Zhen Yin, chang-cheng Chen, Yu Xiang, Ye Peking Univ Hlth Sci Ctr Sch Basic Med Sci Dept Biophys Beijing 100191 Peoples R China Tsinghua Univ Sch Med Dept Basic Med SciCtr Global Hlth & Infect Dis Beijing Adv Innovat Ctr Struct BiolCollaborat In Beijing 100084 Peoples R China Wuhan Univ Coll life Sci State Key Lab Virol Wuhan 430072 Peoples R China

Coronaviruses are enveloped viruses that cause different diseases in humans and animals （Suet al., 2016）. Murine hepatitis virus （MHV） causes hepatitis, enteritis and central nervous system diseases in rodents and is one of the best- studied coronaviruses. MHV belongs to the genera betacoronavirus. Members from the same genera also include highly pathogenic coronaviruses such as the severe acute respiratory syndrome coronavirus （SARS-CoV） and the Middle-East respiratory syndrome coronavirus （MERS-CoV）（Vijay and Perlman, 2016）.

关键词： studies microscopy Electron

Tuning Energy Transfer in Metal-OrganicFrameworks for Fluorescence Turn-on Sensing of Hg(Ⅱ)Ions

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Chinese Journal of Chemistry 2023年第9期41卷 1051-1056页

作者： Xuejiao Wang Arindam Mal Bo gui cheng Wang Sauvage Center for Molecular Sciences and Hubei Key Lab on Organic and Polymeric Optoelectronic Materials College of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

Tuning F?rster resonance energy transfer(FRET)in metal-organic frameworks for fluorescence turn on sensing is rarely ***,we designed and synthesized several FRET-based metal-organic frameworks(MOFs)with different donor/acceptor *** the oxidation of the acceptor,the FRET process in MOFs can be efficiently modulated so as to turn-on the fluorescence of the framework in a controlled ***,the MOF with an optimized donor/acceptor ratio of 7.0 was used as an efficient fluorescence turn on sensor for Hg(Ⅱ)ions with good sensitivity and *** believe our present study will not only give a useful method to construct fluorescence turn-on sensors but also trigger the construction of novel FRET-based MOFs for the fluo-rescence turn-on sensing of target analytes in the future.

关键词： Energy transfer FluorescenceHg(Ⅱ)ions Sensors Metal-organic frameworks

Composite Cathode Based on Redox-Reversible Nb2TiO7 for Direct High-Temperature Steam Electrolysis

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Chinese Journal of Chemical Physics 2015年第3期28卷 323-330,I0002页

作者： Shi-song Li Ji-gui cheng Xu-cheng Zhang Yu Wang Kui Xie Department of Energy Materials School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

Ni/YSZ fuel electrodes can only operate under strongly reducing conditions for steam elec- trolysis in an oxide-ion-conducting solid oxide electrolyzer （SOE）. In atmosphere with a low content of H2 or without H2, cathodes based on redox-reversible Nb2TiO7 provide a promising alternative. The reversible changes between oxidized Nb2TiO7 and reduced Nbl.33Tio.6704 samples are systematically investigated after redox-cycling tests. The conductivities of Nb2TiO7 and reduced Nb1.33Tio.6704 are studied as a function of temperature and oxygen partial pressure and correlated with the electrochemical properties of the composite electrodes in a symmetric cell and SOE at 830 ℃. Steam electrolysis is then performed using an oxide-ion-conducting SOE based on a Nb1.33Ti0.6704 composite fuel electrode at 830 ℃. The current-voltage and impedance spectroscopy tests demonstrate that the reduction and activation of the fuel electrode is the main process at low voltage; however, the steam electrolysis dominates the entire process at high voltages. The Faradic efficiencies of steam electrolysis reach 98.9% when 3%H2O/Ar/4%H2 is introduced to the fuel electrode and 89% for that with introduction of 3%H2O/Ar.

关键词： Redox-reversible Alternative fuel electrode Solid oxide electrolyzer Steamelectrolysis

Local structure engineering for active sites in fuel cell electrocatalysts

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Science China Chemistry 2020年第11期63卷 1543-1556页

作者： Han cheng Renjie gui Si Liu Yi Xie changzheng Wu Hefei National Laboratory for Physical Science at the Microscale CAS Centre for Excellence in NanoscienceCollaborative Innovation Centre of Chemistry for Energy Materials(iChEM)CAS Key Laboratory of Mechanical Behavior and Design of MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230026China

In this review,we surveyed the significance of local structure engineering on electrocatalysts and electrodes for the performance of oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).Both on precious metal catalysts(PMC)and non-precious metal catalysts(NPMC),the main methods to modulate local structure of active sites have been *** change of atomic coordination,modulation of bonding distortion and synergy effect from hierarchical structure,local structure engineering has influence on the intrinsic activity and stability of ***,we emphasized the intimate correlation between lyophobicity of electrocatalysts and membrane electrodes by local structure *** review aimed to inspire the exploration of advanced electrocatalysts and mechanism study for PEMFCs based on local structure engineering.

关键词： local structure engineering proton exchange membrane fuel cells oxygen reduction reaction active sites

Stability analysis and controller design for a class of delay systems via observer based on network

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控制理论与应用（英文版） 2009年第3期7卷 328-334页

作者： Xinming cheng Weihua gui Zhengjia GAN School of Information Science and Engineering Central South University Changsha Hunan 410083 China School of Computer and Communication Changsha University of Science and Technology Changsha Hunan 410076 China

This paper focuses on the problem of stability analysis and controller design for a class of delay systems based on networked control systems. By introducing some free matrix variables, some criteria for stability analysis and observer-based control law design can be obtained by the solving of linear matrix inequalities. A numerical example is also offered to prove the effectiveness of the proposed method.

关键词： Time-delay system Networked control system Stabilization Linear matrix inequality Observer

Leakage Current and Photovoltaic Properties in a Bi_(2)Fe_(4)O_(9)/Si Heterostructure

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Chinese Physics Letters 2011年第8期28卷 258-261页

作者： JIN Ke-Xin LUO Bing-cheng ZHAO Sheng-gui WANG Jian-Yuan CHEN chang-Le Shaanxi Key Laboratory of Condensed Matter Structures and Properties School of ScienceNorthwestern Polytechnical UniversityXi'an 710072

A heterostructure composed of a Bi2Fe4O9 film and an n−type Si substrate is *** characteristics of leakage current density versus electric field are investigated and the leakage current density is about 6×10^(−6) A/cm^(2) at an electric field of 200 kV/cm at 300 K.A strong photovoltaic effect is observed when the heterostructure is exposed to a laser pulse with a wavelength of 532 nm and a power of 6 mW/mm^(2).It is found that the peak photovoltages initially increase with decreasing temperature,followed by a decrease at T<210 *** results reveal that the heterostructure is a promising candidate for photovoltaic devices that are compatible with Si integrated circuits.

关键词： heterostructure initially film

Modeling stochastic mortality with O-U type processes

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Applied Mathematics(A Journal of Chinese Universities) 2018年第1期33卷 48-58页

作者： ZHENG Jing TONG chang-qing ZHANG gui-jun College of Economics Hangzhou Dianzi University

Modeling log-mortality rates on O-U type processes and forecasting life expectancies are explored using U.S. data. In the classic Lee-Carter model of mortality, the time trend and the age-specific pattern of mortality over age group are linear, this is not the feature of mortality model. To avoid this disadvantage, O-U type processes will be used to model the log-mortality in this paper. In fact, this model is an AR(1) process, but with a nonlinear time drift *** on the mortality data of America from Human Mortality database(HMD), mortality projection consistently indicates a preference for mortality with O-U type processes over those with the classical Lee-Carter model. By means of this model, the low bounds of mortality rates at every age are given. Therefore, lengthening of maximum life expectancies span is estimated in this paper.

关键词： mortality stochastic forecasting O-U type process

The Fine Triangle Intersections for Maximum Kite Packings

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Acta Mathematica Sinica,English Series 2013年第5期29卷 867-882页

作者： gui Zhi ZHANG Yan Xun chang Tao FENG Institute of Mathematics Beijing Jiaotong University School of Mathematical Sciences Hulunbuir College

In this paper, the fine triangle intersection problem for a pair of maximum kite packings is investigated. Let Fin（v） = {（s, t）： E← a pair of maximum kite packings of order v intersecting in s blocks and s ＋ t triangles}. Let Adm（v） = {（s,t）： s ＋ t≤by, s, t are non-negative integers}, where by = [v（v - 1）/8]. It is established that Fin（v） = Adm（v）／{（bv - 1,0）, （by - 1, 1）} for any integer v - 0, 1 （rood 8） and v ≥ 8; Fin（v） = Adm（v） for any integer v = 2, 3, 4, 5, 6, 7 （rood 8） and v≥ 4.

关键词： Kite packing triangle intersection fine triangle intersection

Application of Near-Infrared Reflectance Spectroscopy to the Evaluation of D-chiro-Inositol,Vitexin,and Isovitexin Contents in Mung Bean

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Agricultural Sciences in China 2011年第12期10卷 1986-1991页

作者： YAO Yang cheng Xu-zhen REN gui-xing Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

Mung bean （Vigna radiata L.） is rich in D-chiro-inositol （DCI）, vitexin, and isovitexin, which has beneficial effects on antidiabetic and inhibits the formation of advanced glycation end-products. In this study, near-infrared reflectance spectroscopy （NIRS） was used to predict the contents of DCI, vitexin, and isovitexin in mung bean. The spectra data were linearized with those determined by high-performance liquid chromatography （HPLC）. The models for predicting the DCI, vitexin, and isovitexin contents in mung bean were developed using partial least-squares （PLS） algorithm. Cross-validation procedures indicated good correlations between HPLC data and NIRS predictions （R2=0.90 for DCI, R2=0.81 for vitexin, and R2=0.90 for isovitexin）. The predictive contents of DCI, vitexin, and isovitexin ranged from 2.082 to 3.084%, 1.277 to 1.307%, and 0.5998 to 0.6286%, respectively. The results showed that NIRS, a well-established and widely applied technique, could be applied to rapid detection of DCI, vitexin, and isovitexin contents in mung bean.

关键词： D-chiro-inositol, vitexin, isovitexin, NIRS, mung beanMun bean is an imoortant natural so