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A STUDY ON THE STRUCTURAL TRANSITION OF A SINGLE POLYMER CHAIN BY PARALLEL TEMPERING MOLECULAR DYNAMICS SIMULATION

Chinese Journal of Polymer Science 2012年第1期30卷 45-55页

作者： zhou-ting Jiang Peng Xu ting-ting Sun Department of Applied Physics China Jiliang University Hangzhou 310018 China College ofInformation and Electronic Engineering Zhejiang Gongshang University Hangzhou 310018 China

The structural transition of a single polymer chain with chain length of 100,200 and 300 beads was investigated by parallel tempering MD *** simulation results can capture the structural change from random coil to orientationally ordered structure with decreasing *** clear transition was observed on the curves of radius of gyration and global orientational order parameter P as the function of temperature,which demonstrated structural formation of a single polymer *** linear relationships between three components of square radius of gyration R_（gx）~2,R_（gx）~2,R_（gz）~2 and global orientational order P can be obtained under the structurally transformational *** slope of the linear relationship between x（or y-axis） component R_（gx）~2（or R_（gy）~2） and P is negative,while that of RL as the function of P is *** absolute value of slope is proportional to the chain *** the single polymer chain takes the random coil or ordered configuration,the linear relationship is *** conformational change was also analyzed on microscopic *** polymer chain can be treated as the construction of rigid stems connecting by flexible *** deviation from exponentially decreased behavior of stem length distribution becomes prominent,indicating a stiffening of the chain arises leading to more and more segments ending up in the trans state with decreasing *** stem length N_（tr） is about 21 bonds indicating the polymer chain is ordered with the specific fold ***,the simulation results,which show the prototype of a liquid-crystalline polymer chain,are helpful to understand the crystallization process of crystalline polymers.

关键词： A polymer chain Structural transition Parallel tempering molecular dynamics

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Primary stratification and identification of suspected corona virus disease 2019(COVID-19) from clinical perspective by a simple scoring proposal

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Military Medical Research 2020年第4期7卷 503-506页

作者： ting-ting zhou Feng-Xian Wei Department of Respiratory Medicine Lanzhou University Second HospitalLanzhou 730030GansuChina Lanzhou University Second Clinical Medical College Lanzhou UniversityCuiyingmen 82Chengguan DistrictLanzhou 730030GansuChina

In this Commentary,we would like to comment on the article titled"A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus(2019-nCoV)infected pneumonia(standard version)"as a featured article in Military Medical *** the guideline,except for"confirmed cases","suspected cases","close contact"and"suspicious exposure"were defined by clinical perspective based on epidemiological risk,clinical symptoms and auxiliary *** with our experience,we introduced a simple scoring proposal additionally based on not only CT imaging as strongly recommended by the guideline but also blood routine test,especially for primary screening of such patients in the out-patient department.

关键词： COVID-19 Suspected cases Primary screening CT imaging Blood test

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Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-Hui Luo Yue-ting zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

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A digital moiré fringe method for displacement sensors

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 946-953页

作者： Jian WU ting-ting zhou Bo YUAN Li-qiang WANG State Key Laboratory of Modern Optical Instrumentation CNERC for Optical Instrument Zhejiang University

In this study, a displacement measurement method based on digital moiré fringe is described and experimentally demonstrated. The method is formed by only one grating with a constant pitch. First, the magnified grating image is received by an imaging array and is sent to a computer. Then, the digital moiré fringes are generated by overlaying the grating image with its mirrored one. Finally, a specifically designed algorithm is used to obtain the fringes' phase difference before and after movement and calculate the displacement. This method has the effects of amplifying displacement and averaging the grating lines error, the same as the traditional moiré technique using two pieces of gratings. At the same time, the proposed system is much easier to assemble and the measurement resolution can be set more flexibly. One displacement measuring system based on this method was built up. Experiment results show that its measurement errors are less than 0.3 μm and less than 0.12 μm at the resolutions of 0.1 μm and 0.03 μm, respectively.

关键词： Digital moiré fringe Displacement measurement Grating

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Spatio-temporal characteristics and typical patterns of eco-efficiency of cultivated land use in the Yangtze River Economic Belt, China

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Journal of Geographical Sciences 2023年第2期33卷 357-372页

作者： KE Xinli ZHANG Ying zhou ting College of Public Administration Huazhong Agricultural UniversityWuhan 430070China

Identifying the dynamics of the eco-efficiency of cultivated land use(ECLU)is important to balance food security and environmental *** Yangtze River Economic Belt(YREB)is a vital region of national strategic development in ***,the spatio-temporal characteristics and typical patterns of the ECLU in the YREB remain *** study aims to reveal the spatio-temporal characteristics of the ECLU by using the super-efficiency slack-based measure(SBM)and a spatial autocorrelation *** typical patterns of the ECLU were classified based on a decision tree *** results indicate that the overall ECLU increased from 0.78 to 0.87 from 2000 to 2019,dropping sharply in 2003 before rising *** reaches had similar *** local indicators of spatial association(LISA)cluster reflect that the spatial distributions of high-high and low-low agglomeration varied dramatically among these *** ECLU was divided into three typical patterns considering the restriction of agrochemicals and water resources(RAW),cultivated land and agrochemicals(RCA),as well as technology(RT).Most cities belonged to the low ECLU category in RT *** understanding the spatio-temporal characteristics and classification of the ECLU will provide a reference for decision-makers to improve the ECLU in different regions.

关键词： ecological efficiency cultivated land use super-efficiency SBM carbon emissions classification Yangtze River Economic Belt,China

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Co-based MoF derived metal catalysts: from nano-level to atom-level

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Tungsten 2023年第2期5卷 201-216页

作者： Yuan-Xin Du Yan-ting zhou Man-zhou Zhu College of Materials Science and Engineering and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials Department of Chemistry and Center for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of the Ministry of EducationAnhui UniversityHefei 230601China

Co-based metal-organic framework(MOF),a kind of porous crystal material composed of Co ions and organic linkers,is a common type of *** not only has the intrinsic properties of MOF,such as structural diversity,functional adjustability,and high surface area,but more importantly,it contains Co metal species,which are considered by many reports to be active catalytic centers for many ***,metal catalysts always received wide and sustained *** combi-nation of the two types of catalysts can enhance the catalytic performance and achieve the"1+1>2"*** this review,we mainly overview the synthesis methods of Co-based MOF-derived metal catalysts from nano-to atom-level and their applications in the catalysis field in recent years and put forward our own views and prospects for this research direction.

关键词： Metal-organic framework Cobalt Catalysis Nanoparticle Nanocluster Single-atom catalyst

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Surface modification of Ti-49.8at%Ni alloy by Ti ion implantation: phase transformation, corrosion, and cell behavior

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 868-875页

作者： Yan Li ting zhou Peng Luo Shuo-gui Xu School of Materials Science and Engineering Beihang University Changhai Hospital Department of Emergency the Second Military Medical University

The Ti-49.8at%Ni alloy was modified by Ti ion implantation to improve its corrosion resistance and biocompatibility. The chemical composition and morphologies of the Ti Ni alloy surface were determined using atomic force microscopy(AFM), auger electron spectroscopy(AES), and X-ray photoelectron spectroscopy(XPS). The results revealed that Ti ion implantation caused the reduction of Ni concentration and the formation of a Ti O2 nano-film on the Ti Ni alloy. The phase transformation temperatures of the Ti–Ti Ni alloy remained almost invariable after Ti ion implantation. Electrochemical tests indicated that the corrosion resistance of Ti Ni increased after Ti ion implantation. Moreover, the Ni ion release rate in 0.9% Na Cl solution for the Ti Ni alloy remarkably decreased due to the barrier effect of the Ti O2 nano-film. The cell proliferation behavior on Ti-implanted Ti Ni was better than that on the untreated Ti Ni after cell culture for 1 d and 3 d.

关键词： titanium–nickel alloys surface modification ion im

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How does tree age influence damage and recovery in forests impacted by freezing rain and snow?

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Science China(Life Sciences) 2015年第5期58卷 472-479页

作者： ZHU LiRong zhou ting CHEN BaoMing PENG ShaoLin State Key Laboratory of Biocontrol Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education InstitutesSchool of Life Sciences Sun Yat-sen University

The response and recovery mechanisms of forests to damage from freezing rain and snow events are a key topic in forest research and management. However, the relationship between the degree of damage and tree age, i.e., whether seedlings, young trees, or adult trees are most vulnerable, remains unclear and is rarely reported. We investigated the effect of tree age on the degrees of vegetation damage and subsequent recovery in three subtropical forest types-coniferous, mixed, and broad-leaved —in the Tianjing Mountains, South China, after a series of rare icy rain and freezing snow events in 2008. The results showed that damage and recovery rates were both dependent on tree age, with the proportion of damaged vegetation increasing with age(estimated by diameter at breast height, DBH) in all three forest types and gradually plateauing. Significant variation occurred among forest types. Young trees in the coniferous forest were more vulnerable than those in the broad-leaved forest. The type of damage also varied with tree age in different ways in the three forest types. The proportion of young seedlings that were uprooted(the most severe type of damage) was highest in the coniferous forest. In the mixed forest, young trees were significantly more likely to be uprooted than seedlings and adult trees, while in the broad-leaved forest, the proportion of uprooted adult trees was significantly higher than that of seedlings and young trees. There were also differences among forest types in how tree age affected damage recovery. In the coniferous forest, the recovery rate of trees with broken trunks or crowns(DBH > 2.5 cm) increased with tree age. However, in the mixed and broad-leaved forests, no obvious correlation between the recovery rate of trees with broken trunks or crowns and tree age was observed. Trees with severe root damage did not recover; they were uprooted and died. In these forests, vegetation damage and recovery showed tree age dependencies, which varied with

关键词： freezing rain and snow tree age damage restoration subtropical forest

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Scalar field in massive BTZ black hole and entanglement entropy

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Chinese Physics C 2020年第1期44卷 129-135页

作者： Yu-ting zhou Xiao-Mei Kuang College of Mathematics and Science Yangzhou UniversityYangzhou 225009China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

In this paper,we investigate the quantum scalar fields in a massive BTZ black hole *** study the entropy of the system by evaluating the entanglement entropy using a discretized ***,we fit the results with a log-modified formula of the black hole entropy,which is introduced by quantum *** coefficients of leading and sub-leading terms affected by the mass of graviton are numerically analyzed.

关键词： massive BTZ black hole entanglement entropy scalar field

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Circularly Polarized Luminescence and SHG Chiral Signals of Helical TPE Macrocycles

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Chinese Journal of Chemistry 2021年第12期39卷 3353-3359页

作者： Ying-Xue Yuan Ming Hu Man Xue ting-ting zhou Zhen Zhang Yan-Song Zheng Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhanHubei 430074China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Molecular Reaction DynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

One pair of new enantiomers of helical tetraphenylethylene(TPE)tetracycle tetradodecylurea,which show aggregation-induced emission(AIE)enhancement effect,were synthesized by attaching four dodecyl chains to a helical TPE tetracycle tetramine through urea *** two TPE helicates bearing long alkyl chains could display strong circular dichroism(CD)and circularly polarized luminescence(CPL)signals not only in solution but also in solid *** to strong van der Waals interactions between the alkyl chains,the absolute dissymmetrical factor|glum|was up to 6.6×10^(-3),which was 2-3 fold larger than that of the helical TPE tetracycle tetramine(TPETA)without long alkyl chains in *** to bearing hydrophilic urea units and hydrophobic long dodecyl chains,the helical TPE tetracycle could form chiral Langmuir-Blodgett(LB)monolayers at air/water interface and showed a strong and stable second harmonic generation(SHG)chiral *** degree of chiral excess(DCE)for P-isomer monolayer was up to-0.682±*** is the first example to detect chirality at the air/water interface for chiral AIE *** provides a new access to the application of chiral AIE compounds in nonlinear optical activity.

关键词： Helical TPE macrocycles Aggregation Circularly polarized luminescence Host-guest systems Monolayers

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