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Electron and configuration engineering of atomic Cu and multioxidated Cu_(2+1)O centers via gasifiable reductant strategy for efficient oxygen reduction toward Zn-air battery

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Nano Research 2023年第2期16卷 2383-2391页

作者： Hongbin Li Jia-Jia zheng Mingfan Yang Jingui duan State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Laboratory of Theoretical and Computational Nanoscience National Center for Nanoscience and TechnologyChinese Academy of SciencesBeijing 100190China

Efforts in a large number of transition metal-carbon systems are devoted to the development of efficient catalysts for oxygen reduction reaction(ORR).However,unsatisfied O_(2)adsorption and slow reduction of OH*at the active centers hinder the further development of these *** here report a gasifiable reductant strategy,of which a new Cu-based metal organic framework(MOF:termed NTU-83)nanosheet was co-pyrolyzed with melamine to produce the N-coordinated atomic Cu and multi-oxidated Cu_(2+1)O active centers on the carbon foam with ultrathin *** engineered electrons and configuration of the active centers boost the catalyst(Cu/NC-1000)to show superior ORR activity(E_(1/2)=0.85 V),excellent stability,and methanol *** modeling calculation and controlled experiments reveal that the Cu_(2+1)O species play a crucial role in kinetically accelerated adsorption and activation of O_(2),while the N_(4)coordinated atomic Cu facilitates fast reduction of OH*.Such characteristics endow the Zn-air battery that containing Cu/NC-1000 as air cathode to show a high peak power density(138 mW·cm^(−2)),a high specific capacity of 763 mAh·gZn^(−1),and outstanding long-term cycle *** plausible mechanism and excellent performance show that gasifiable reductant strategy opens up a new route for regulation of the electronic of active sites but also provides a candidate for the practical application in energy conversion/storage devices.

关键词： metal organic framework nanosheet carbon foam atomic Cu Cu_(2+1)O nanosheet electron and configuration engineering

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Synthesis and Characterization of a Novel Functional Biodegradable Copolymer-Poly(lactic acid-4-hydroxyproline-polyethylene glycol)

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Chinese Chemical Letters 2006年第8期17卷 1125-1128页

作者： Jiu Fang duan Yu Bin zheng Department of Polymer Science Dalian University of Technology Dalian 116012

A series of poly（lactic acid-4-hydroxyproline-polyethylene glycol）（PLA-Hpr-PEG） copolymers were synthesized by direct melt copolymerization of D,L-lactic acid and 4-hydroxyproline with different feed amount of polyethylene glycol （PEG） 0.1%, 0.5%, 1% and 5%, respectively. The properties of these copolymers were characterized by using IR spectroscopy, proton nuclear magnetic resonance （1H-NMR） spectroscopy, gel permeation chromatography （GPC）, X-ray diffraction and differential scaning calorimetry （DSC）. PLA-Hpr-PEG are amorphous copolymers. Copolymers showed increasing water uptake capacity with increasing PEG percentage in the feed, which result in an increasing degradable rate in phosphate buffer solution （pH 7.4） at 37℃.

关键词： Lactic acid 4-hydroxyproline polyethylene glycol.

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“Sentinel or accomplice”:gut microbiota and microglia crosstalk in disorders of gut-brain interaction

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Protein & Cell 2023年第10期14卷 726-742页

作者： Haonan zheng Cunzheng Zhang Jindong Zhang Liping duan Department of Gastroenterology Peking University Third HospitalBeijing 100191China Beijing Key Laboratory for Helicobacter Pylori Infection and Upper Gastrointestinal Diseases Beijing 100191China

Abnormal brain-gut interaction is considered the core pathological mechanism behind the disorders of gut-brain interaction(DGBI),in which the intestinal microbiota plays an important *** are the“sentinels”of the central nervous system(CNS),which participate in tissue damage caused by traumatic brain injury,resist central infection and participate in neurogenesis,and are involved in the occurrence of various neurological *** in-depth research on DGBI,we could find an interaction between the intestinal microbiota and microglia and that they are jointly involved in the occurrence of DGBI,especially in individuals with comorbidities of mental disorders,such as irritable bowel syndrome(IBS).This bidirectional regulation of microbiota and microglia provides a new direction for the treatment of *** this review,we focus on the role and underlying mechanism of the interaction between gut microbiota and microglia in DGBI,especially IBS,and the corresponding clinical application prospects and highlight its potential to treat DGBI in individuals with psychiatric comorbidities.

关键词： gut microbiota microglia disorders of gut-brain interaction irritable bowel syndrome

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Investigation of Self-Priming Process of a Centrifugal Pump with Double Blades

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Journal of Thermal Science 2021年第3期30卷 849-858页

作者： QIAN Heng mou Jiegang REN Yun ZHU Zhibing LIU Nuojia zheng Shuihua WU Denghao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China Zhijiang College Zhejiang University of TechnologyShaoxing 312030China

The gas-liquid two-phase flow patterns of a centrifugal pump during the self-priming process were investigated numerically and *** Euler-Euler multiphase model and SST k-ω turbulence model were applied for simulating the self-priming ***,the changes of motor speed and self-priming height were considered in the *** overall transient two-phase flow features and water level distributions were *** showed that the self-priming process was divided into three *** liquid level in inlet-pipe rose in oscillation during self-priming *** variations of water level during self-priming process of numerical simulation and test result agreed *** inlet-pipe(Ver)was filled at 22 s and 24 s respectively numerically and *** bubble cloud circulated in the volute during middle stage of self-priming process,and breakup into smaller bubbles by shear force and tongue,and then discharged into *** bubbles in the outlet-pipe mainly included bubbly flow and slug flow at the last stage of self-priming process,which is morphologically consistent with the test ***,during the self-priming process,the reflux liquid was pressed by blades and fully mixed with gas;that is the way to realizing the function of self-priming.

关键词： self-priming process gas-liquid two-phase flow centrifugal pump gas-liquid mixing and separation transient numerical simulation

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Land cover classification from remote sensing images based on multi-scale fully convolutional network

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Geo-Spatial Information Science 2022年第2期25卷 278-294页

作者： Rui Li Shunyi zheng Chenxi duan Libo Wang Ce Zhang School of Remote Sensing and Information Engineering Wuhan UniversityWuhanChina Faculty of Geo-Information Science and Earth Observation(ITC) University of TwenteEnschedeThe Netherlands The State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Lancaster Environment Centre Lancaster UniversityLancasterUK UK Centre for Ecology&Hydrology LancasterUK

Although the Convolutional Neural Network(CNN)has shown great potential for land cover classification,the frequently used single-scale convolution kernel limits the scope of informa-tion ***,we propose a Multi-Scale Fully Convolutional Network(MSFCN)with a multi-scale convolutional kernel as well as a Channel Attention Block(CAB)and a Global Pooling Module(GPM)in this paper to exploit discriminative representations from two-dimensional(2D)satellite ***,to explore the ability of the proposed MSFCN for spatio-temporal images,we expand our MSFCN to three-dimension using three-dimensional(3D)CNN,capable of harnessing each land cover category’s time series interac-tion from the reshaped spatio-temporal remote sensing *** verify the effectiveness of the proposed MSFCN,we conduct experiments on two spatial datasets and two spatio-temporal *** proposed MSFCN achieves 60.366%on the WHDLD dataset and 75.127%on the GID dataset in terms of mIoU index while the figures for two spatio-temporal datasets are 87.753%and 77.156%.Extensive comparative experiments and abla-tion studies demonstrate the effectiveness of the proposed MSFCN.

关键词： Spatio-temporal remote sensing images Multi-Scale Fully Convolutional Network land cover classification

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Recent Advances in Mathematical Programming with Semi-continuous Variables and Cardinality Constraint

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Journal of the Operations Research Society of China 2013年第1期1卷 55-77页

作者： Xiaoling Sun Xiaojin zheng duan Li Department of Management Science School of ManagementFudan UniversityShanghai 200433P.R.China School of Economics and Management Tongji UniversityShanghai 200092P.R.China Department of Systems Engineering and Engineering Management The Chinese University of Hong KongShatinN.T.Hong Kong

Mathematical programming problems with semi-continuous variables and cardinality constraint have many applications,including production planning,portfolio selection,compressed sensing and subset selection in *** class of problems can be modeled as mixed-integer programs with special structures and are in general *** the past few years,based on new reformulations,approximation and relaxation techniques,promising exact and approximate methods have been *** survey in this paper these recent developments for this challenging class of mathematical programming problems.

关键词： Semi-continuous variables Cardinality and sparsity constraint Mixed-integer 0-1 quadratic programming Perspective reformulation Lagrangian decomposition Approximate methods

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Characterization of a collection of Chinese fir elite genotypes using *** amplified polymorphism markers

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Journal of Forestry Research 2016年第5期27卷 1105-1110页

作者： Hongjing duan Dehuo Hu Yun Li Huiquan zheng National Engineering Laboratory for Tree Breeding Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of Education College of Biological Sciences and Technology Beijing Forestry University Beijing 100083 People's Republic of China Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest Guangdong Academy of ForestryGuangzhou 510520 People's Republic of China

Chinese fir [Cunninghamia lanceolata （Lamb.） Hook] is a major timber tree species in China. In the pre- sent study, sequence-related amplified polymorphism （SRAP） markers were used to evaluate the polymorphisms, diversity, and relationships in a collection of Chinese fir elite genotypes （n = 103） from the Lechang provenance, an endangered provenance. Thirty-five SRAP primer combinations produced 620 bands among the tested 103 Lechang provenance genotypes and 17 nonSLechang provenance genotypes; 577 （93.1%） of these were polymorphic, yielding an average of 16.5 polymorphic bands per primer combination. Of the SRAP primer combinations （n = 35）, I4 ones identified 〉70.0 % of the 120 genotypes. The Mel2-Eml9 combination had the strongest discriminatory ability with 93.3 % of the genotypes iden- tified. An UPGMA dendrogram further showed that most of the Lechang provenance genotypes （87.4 %） grouped together （Cluster A）. The Lechang genotypes had a con- siderable amount of genetic variation with genetic simi- larity from 0.40 to 0.81. The current work may facilitate the management of the endangered Lechang Chinese fir provenance.

关键词： Chinese fir SRAP Germplasm Geneticvariation - Dendrogram

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老年特发性正常压力脑积水患者的姿势稳定性特征

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中国组织工程研究 2025年第6期29卷 1208-1213页

作者：梁晓笑郑洁皎段林茹陈茜张廷宇上海中医药大学康复医学院上海市201203 复旦大学附属华东医院上海市200040

背景:姿势控制能力受损是特发性正常压力脑积水患者发生跌倒、引发继发性损害的重要危险因素,现有研究大多是对患者直线行走时的步态参数进行分析,鲜有对患者在静态与动态活动中的姿势稳定性特征进行分析。目的:分析老年特发性正常压力... 详细信息

背景:姿势控制能力受损是特发性正常压力脑积水患者发生跌倒、引发继发性损害的重要危险因素,现有研究大多是对患者直线行走时的步态参数进行分析,鲜有对患者在静态与动态活动中的姿势稳定性特征进行分析。目的:分析老年特发性正常压力脑积水患者的姿势稳定性特征。方法:选择2022年9月至2023年2月在上海市复旦大学附属华东医院神经外科临床诊断为特发性正常压力脑积水的患者22例作为患者组,同时选择健康陪诊家属18名作为健康对照组。分别采用计时起立-行走测试、多方向性伸展测试、Berg平衡量表和静态平衡功能测试(反应时间、移动速度、方向控制、最大偏移距离、端点行程)评估受试者的姿势稳定性特征。结果与结论:①患者组完成计时起立-行走测试所需时间及静态平衡功能测试的反应时间均长于健康对照组(P<0.05),前、后、左、右方向上的伸展测试手臂伸展距离均小于健康对照组(P<0.05),Berg平衡量表得分低于健康对照组(P<0.05),静态平衡功能测试的移动速度、方向控制、最大偏移距离和端点行程均小于健康对照组(P<0.05)。②结果提示,特发性正常压力脑积水患者表现出整体的姿势控制能力障碍,反应能力与执行能力受损使得这类患者在面对来自内部或外部的干扰时无法做出及时、准确的运动反应而出现姿势不稳,增加了发生跌倒的风险。

关键词：特发性正常压力脑积水姿势控制姿势稳定性跌倒风险平衡功能

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Molecular dynamics study on the nano-void growth and coalescence at grain boundary

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 86-93页

作者： LIN EnQiang NIU LiSha SHI HuiJi duan zheng Applied Mechanics Laboratory School of Aerospace Tsinghua University Beijing 100084 China

Molecular dynamics simulations using embedded atom method (EAM) potential were performed to study nano-void growth and coalescence at grain boundary in face-centered cubic bicrystal copper. Thin-plate specimens subjected to uniaxial tension strain with one-void and two-void at the centered grain boundary were employed to analyze the effect of specimen size, temperature and applied strain rate on the stress-strain response, incipient yield strength and macroscopic effective Young's modulus. The evolutions of dislocations, twin bands and void shapes under different specimen sizes were also presented. The obtained results show that, regardless of the void numbers, the specimen sizes, temperature, the applied strain rate had significant influence on the void shape evolution, stress-strain curve and incipient yield strength, while negligible effects on the macroscopic effective Young's modulus except for the temperature. Moreover, the voids growth rate along the grain boundary was also found to be associated with the specimen sizes.

关键词： bicrystal void growth void coalescence grain boundary molecular dynamics simulations embedded atom method

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Sensitivity of Potential Evapotranspiration Estimation to the Thornthwaite and Penman–Monteith Methods in the Study of Global Drylands

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Advances in Atmospheric Sciences 2017年第12期34卷 1381-1394页

作者： Qing YANG Zhuguo MA Ziyan zheng Yawen duan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Drylands are among those regions most sensitive to climate and environmental changes and human-induced *** most widely accepted definition of the term dryland is a ratio,called the Surface Wetness Index(SWI),of annual precipitation to potential evapotranspiration(PET)being below *** is commonly estimated using the Thornthwaite(PET Th)and Penman–Monteith equations(PET PM).The present study compared spatiotemporal characteristics of global drylands based on the SWI with PET Th and PET *** showed vast differences between PET Th and PET PM;however,the SWI derived from the two kinds of PET showed broadly similar characteristics in the interdecadal variability of global and continental drylands,except in North America,with high correlation coefficients ranging from 0.58 to *** was found that,during 1901–2014,global hyper-arid and semi-arid regions expanded,arid and dry sub-humid regions contracted,and drylands underwent interdecadal *** was because precipitation variations made major contributions,whereas PET changes contributed to a much lesser ***,distinct differences in the interdecadal variability of semi-arid and dry sub-humid regions were *** indicated that the influence of PET changes was comparable to that of precipitation variations in the global dry–wet transition ***,the contribution of PET changes to the variations in global and continental drylands gradually enhanced with global warming,and the Thornthwaite method was found to be increasingly less applicable under climate change.

关键词： potential evapotranspiration global drylands Thornthwaite Penman–Monteith

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