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Journal of Energy Chemistry 2020年第7期29卷 71-77,I0003页

作者： Tingting Wang Kaiwei Yang Juan Shi Shangrui Zhou Liwei Mi Hongping Li Weihua Chen Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina Center for Advanced Materials Research Zhongyuan University of TechnologyZhengzhou 450007HenanChina

Metal selenides owing to their high theoretical capacity and good conductivity are considered as one of the potential candidates for the anode materials of sodium-ion batteries(SIBs).However,their practical applications are greatly restricted by the poor cycling performances and complicated synthesis methods.In this work,a sandwich-like Sn Se2/reduced graphene oxide(r GO)composite with a small amount of r GO(7.3%)is synthesized by a simple one-pot solvothermal technique.The as-synthesized Sn Se2/r GO shows improved initial coulombic efficiency(ICE)of 73.7%,high capacity of 402.0 m Ah g-1 after 150 cycles at 0.1 A g-1 with a retention of 86.2%and outstanding rate performances.The abundant Sn-O-C bonds of synthesized material not only accelerate the charge transfer at the interface but also enhance the mechanical strength to accommodate volume variation and prevent active material loss during cycling.Moreover,the compact structure leads to thin solid electrolyte interface(SEI)so that high initial coulombic efficiency was obtained.Furthermore,full cells are assembled to test its potential application.This work offers a simple method to synthesize Sn Se2/r GO as a candidate anode for SIBs.

关键词： Sodium-ion batteries Initial coulombic effciency Ex-situ XRD SEI Tin diselenide

Electrochemical characterization and microstructure of cold sprayed AA5083/Al_(2)O_(3) composite coatings

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Journal of Materials Science & Technology 2020年第24期59卷 117-128页

作者： Xiawei yang Wenya Li Siqi Yu Yaxin Xu kaiwei Hu Yaobang Zhao State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Shanghai Aerospace Precision Machinery Research Institute Shanghai 201600China

This work focused on the role of Al_(2)O_(3) particles in the corrosion behavior of cold sprayed AA5083 aluminum alloy matrix composite(Al-MMC)coatings.The electrochemical characterization of the coatings was investigated in a 3.5 wt.%NaCl solution as a function of time.The results show that fragmentation of Al_(2)O_(3) particles is not clearly observed in the case of AA5083/20 vol.%Al_(2)O_(3) coating,while the broken Al_(2)O_(3) particles can be seen clearly in AA5083/40 vol.%Al_(2)O_(3) and AA5083/60 vol.%Al_(2)O_(3) coatings.The addition of 20 vol.%Al_(2)O_(3) particles yield the coating with the lowest porosity,and different volume fractions of Al_(2)O_(3)in the feedstock have important effects on the electrochemical behavior of composite coatings.The Al-MMC coating reinforced with 20 vol.%Al_(2)O_(3) particles exhibits the highest Ecorrand the lowest icorrcompared with the other conditions.The order of current density is as follows:AA5083/20vol.%Al_(2)O_(3)

关键词： Cold spray Aluminum alloy Alumina particles Composite coating Electrochemical characterization

A correlation interferometer based spoofing detection technology research

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A correlation interferometer based spoofing detection techno...

A follow up study of cycle threshold values of SARS-CoV-2 in Hunan Province,China

第七届中国卫星导航学术年会

作者： Fan Guangwei YU Baoguo yang kaiwei State Key Laboratory of Satellite Navigation System and Equipment Technology

ISBN: (纸本)9789811009334

For detection and identification of GNSS spoofing,this paper proposes to use multi-antenna two-channel direction-finding method and the carrier phase observed quantities that are provided by the receiver to estimate the arrival direction of GNSS signal or spoofing signal,which is then compared with the ephemeris data solved by the receiver.In such a way,it is possible to make high-precision estimation of the arrival direction of spoofing signal.The validity of the proposed algorithm was validated with a simulation test..

关键词： spoofing carrier phase detection

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Infectious Disease Modelling 2023年第1期8卷 203-211页

作者： Guzainuer Abudurusuli kaiwei Luo Xiaohao Guo Zeyu Zhao Yichao Guo Buasiyamu Abudunaibi Shiting yang Hongjie Wei Shanlu zhao Zhihui Dai Qianlai Sun Hao yang Shixiong Hu Tianmu Chen State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamen CityFujian ProvincePeople's Republic of China Hunan Provincial Center for Disease Control and Prevention Changsha City410001Hunan ProvincePeople's Republic of China

Since the epidemic of the severe acute respiratory syndrome coronavirus 2(SARS-COV-2),many governments have used reverse transcription polymerase chain reaction(RT-PCR)to detect the virus.However,there are fewer measures of CT values information based on RT-PCR results,and the relationship between CT values and factors from consecutive tests is not clear enough.So in this study,we analyzed the connection between CT values and the factors based on cohort data from Delta variant of SARS-CoV-2 in Hunan Province.Previous studies have showed that the mean age of the cases was 33.34 years(±18.72 years),with a female predominance(55.03%,n=71),and the greatest proportion of clinical symptoms were of the common type(60.47%,n=78).There were statistical differences between the N and ORF1ab genes in the CT values for the cases.Based on the analysis of the association between CT values and the factors,the lowest CT values were obtained for the unvaccinated,older and clinically symptomatic group at 3e10 days,the maximum peak of viral load occurred.Therefore,it is recommended to use patient information to focus on older,clinically symptomatic,unvaccinated patients and to intervene promptly upon admission.

关键词： SARS-COV-2 CT values Delta variant Influencing factors

Transmission Dynamics and Epidemiological Characteristics of the SARS-CoV-2 Delta Variant ― Hunan Province, China, 2021

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China CDC weekly 2023年第3期5卷 56-62,I0006-I0009页

作者： kaiwei Luo Yanpeng Wu Yan Wang Ziyan Liu Lan Yi Shanlu Zhao Xuemei Yan Hao yang Kaiyuan Sun Marco Ajelli Shixiong Hu Hongjie Yu Hunan Provincial Center for Disease Control and Prevention Workstation for Emerging Infectious Disease Control and PreventionChinese Academy of Medical SciencesChangsha CityHunan ProvinceChina Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghai MunicipalityChina School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghai MunicipalityChina Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA Laboratory of Computational Epidemiology and Public Health Department of Epidemiology and BiostatisticsIndiana University School of Public HealthBloomingtonINUSA

Monitoring changes in the epidemiologic features between different severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants is key to understanding the evolution of viral fitness in the host population.Here,we analyzed a successfully contained local outbreak of the Delta variant that took place in Hunan,China,in July–August,2021.Detailed data on SARS-CoV-2 infections and their contacts were collected during the outbreak.By leveraging these data,we estimated key epidemiological parameters,including the incubation period,serial interval,and generation time.We constructed a generalized linear mixed-effects model(GLMM)to quantify risk factors for Delta infection and transmission.Between July 28 and August 15,2021,a total of 129 infections and their 2,118 close contacts were identified during the outbreak in Hunan Province.

关键词： Hunan population Province

The realization of the RTK algorithm based on GPS/BDS OEM board and the test of its performance

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The realization of the RTK algorithm based on GPS/BDS OEM bo...

Contact pattern,current immune barrier,and pathogen virulence determines the optimal strategy of further vaccination

第五届中国卫星导航学术年会

作者： Du Conghui yang kaiwei Guo Qiang Zhang Jianwei The 54th Research Institute of CETC Satellite Navigation Technology and Equipment Engineering Technology Research Center of Hebei province

ISBN: (纸本)9783642547362

Using the high‐accuracy OEM board,which contains of BDS B1/B2/B3 and GPS L1/L2 frequency,this paper realized the embedded algorithm of RTK of BDS,GPS and BDS+GPS.Both static and ground kinematic tests were carried out to evaluate the precision of the embedded algorithm of RTK from BeiDou,GPS and BDS+GPS.In static mode,the results demonstrated that the accuracy ofstatic zero‐baseline was sub‐mm for the horizontal component and 1mm for vertical component using BDS.The proportion of the fix resultswere higher than 98%.The accuracy of GPS for 10km static baseline,whose difference of horizontal component was smaller than 1cm and the vertical component was smaller than 3cm,was better than BDS,whose difference for three component was better than 4cm.The statistics accuracy of GPS for 10km baseline was better than 4mm for horizontal component and better than 2cm for vertical component,and the BDS was better than 1.5cm for horizontal component and better than 3.5cm for vertical component.The proportion of the fix resultswere higher than 95%.For kinematic baseline,the result of integration positioning was accordant to the real topography,and the standard deviation of adjustment of every epochwas better than 6mm.

关键词： RTK BeiDou GPS integration positioning high‐accuracy board.

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Infectious Disease Modelling 2023年第1期8卷 192-202页

作者： Xiaohao Guo Ziyan Liu Shiting yang Zeyu Zhao Yichao Guo Guzainuer Abudurusuli Shanlu Zhao Ge Zeng Shixiong Hu kaiwei Luo Tianmu Chen State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamen City361102Fujian ProvincePeople's Republic of China Hunan Provincial Center for Disease Control and Prevention 405 Furong Middle Road Section OneKaifu DistrictChangsha City410001Hunan ProvincePeople's Republic of China

Background:The current outbreak of novel coronavirus disease 2019 has caused a seriousdisease burden worldwide.Vaccines are an important factor to sustain the epidemic.Although with a relatively high-vaccination worldwide,the decay of vaccine efficacy andthe arising of new variants lead us to the challenge of maintaining a sufficient immunebarrier to protect the population.Method:A case-contact tracking data in Hunan,China,is used to estimate the contactpattern of cases for scenarios including school,workspace,etc,rather than ordinary susceptible population.Based on the estimated vaccine coverage and efficacy,a multi-groupvaccinated-exposed-presymptomatic-symptomatic-asymptomatic-removed model(VEFIAR)with 8 age groups,with each partitioned into 4 vaccination status groups isdeveloped.The optimal dose-wise vaccinating strategy is optimized based on the currentlyestimated immunity barrier of coverage and efficacy,using the greedy algorithm thatminimizes the cumulative cases,population size of hospitalization and fatality respectivelyin a certain future interval.Parameters of Delta and Omicron variants are used respectivelyin the optimization.Results:The estimated contact matrices of cases showed a concentration on middle ages,and has compatible magnitudes compared to estimations from contact surveys in otherstudies.The VEFIAR model is numerically stable.The optimal controled vaccination strategy requires immediate vaccination on the un-vaccinated high-contact population of age30e39 to reduce the cumulative cases,and is stable with different basic reproductionnumbers(R_(0)).As for minimizing hospitalization and fatality,the optimized strategy requires vaccination on the un-vaccinated of both aged 30e39 of high contact frequencyand the vulnerable older.Conclusion:The objective of reducing transmission requires vaccination in age groups ofthe highest contact frequency,with more priority for un-vaccinated than un-fully or fullyvaccinated.The objective of reducing total hospitalization and fatality requires not only tor

关键词： Vaccine Allocation strategy SARS-CoV-2 Optimal control Immune barrier Contact pattern Greedy algorithm

Design and Implementation of Integrated Navigation and Positioning System for Towed Streamer Marine Seismic Exploration

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Design and Implementation of Integrated Navigation and Posit...

Single site catalyst with enzyme-mimic micro-environment for electroreduction of CO_(2)

第十四届中国卫星导航年会

作者： Haonan Zhang kaiwei Sang Cuilin Kuang Chufeng Duan Baocai yang School of Geoscience and Info-physics Central South University China Oilfield Services Limited Geophysical Division

The integrated navigation system serves as the command-and-control center for the offshore towed streamer seismic exploration, and its positioning results of seismic sources and receiver array are also the key to inversion of seabed geological structure using seismic data. In recent decades, China’s marine geophysical exploration integrated navigation system has been reliant on imports, which is expensive and constrained in key technologies. Therefore, to break the technical blockade imposed by foreign geophysical manufacturers and safeguarding the country’s energy security, it is of great strategic significance to independently carry out the research and development of the integrated navigation system for offshore streamer seismic exploration. This research presents critical algorithms for streamer positioning data processing in realtime, near-real-time, and post-processing scenarios, respectively. And the basic architecture and function modules of the integrated navigation system developed are given based on the requirement analysis. Furthermore, the system is tested and verified using both simulation and measured data. The results demonstrate that the shot prediction accuracy of the system is better than 0.5 m in the along line direction, and the streamer positioning accuracy with simulation data in real time, near real time and post processing are better than 6m, 3 m and 2.2 m, respectively. Additionally, the streamer positioning results of the measured data are close to those of mainstream foreign commercial software, indicating that the system meets the operation requirements of offshore streamer seismic exploration. At present, the system has been formally installed and implemented on some geophysical exploration vessels, and has achieved good application results in the exploration in South China Sea and Bohai Sea.

关键词：

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Nano Research 2022年第3期15卷 1817-1823页

作者： Chang Long kaiwei Wan Xueying Qiu Xiaofei Zhang Jianyu Han Pengfei An Zhongjie yang Xiang Li Jun Guo Xinghua Shi Hui Wang Zhiyong Tang Shaoqin Liu School of Materials Science and Engineering MOE Key Laboratory of Micro-systems and Micro-structures ManufacturingHarbin Institute of TechnologyHarbin150080China CAS key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China University of Chinese Academy of Sciences Beijing100049China Institute of High Energy Physics CAS Beijing100049China

Single site catalysts provide a unique platform for mimicking natural enzyme due to their tunable interaction between metal center and coordinated ligand.However,most works have focused on preparing structural and functional models of nature enzyme,with less reports also taking the local chemical environment,i.e.,functional/catalytic residues around the active site which is an essential feature of enzymes,into consideration.Herein,we report a Co-centered porphyrinic polymer containing the enzyme-mimic micro-environment,where the linker triazole over CoN4 site enables formation of hydrogen bond with the*COOH intermediate,thus promoting the electrocatalytic reduction of CO_(2).As-prepared catalyst achieves the CO_(2)-to-CO conversion of 5,788 h^(−1) turnover frequency value and near unit(~96%)faradaic efficiency at−0.61 V versus reversible hydrogen electrode.This strategy will bring new dimension of designing highly active single-site catalysts.

关键词： single-site catalyst CO_(2)electroreduction enzyme-mimic

自拟四步理筋手法治疗拇指狭窄性腱鞘炎30例临床观察

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中国民族民间医药 2023年第2期32卷 95-98页

作者：杨宇张开伟贵州中医药大学贵州贵阳550025 贵州中医药大学第一附属医院贵州贵阳550001

目的:在“以筋为先”理论指导下,观察四步理筋手法治疗拇指狭窄性腱鞘炎的有效性。方法:运用四步理筋手法跟传统手法各治疗30例拇指狭窄性腱鞘炎患者,分别治疗6次,每周3次。观察治疗前后的临床疗效、视觉模拟评分(VAS)变化及随访治疗15... 详细信息

目的:在“以筋为先”理论指导下,观察四步理筋手法治疗拇指狭窄性腱鞘炎的有效性。方法:运用四步理筋手法跟传统手法各治疗30例拇指狭窄性腱鞘炎患者,分别治疗6次,每周3次。观察治疗前后的临床疗效、视觉模拟评分(VAS)变化及随访治疗15天后的复发率,差异均具有统计学意义(P<0.05)。结果:治疗后,观察组视觉模拟评分(VAS)、治疗15天后的复发率明显低于对照组,差异具有统计学意义(P<0.05);治疗后,对照组总有效率73.33%,观察组总有效率93.33%,差异具有统计学意义(P<0.05)。结论:四步理筋手法治疗拇指狭窄性腱鞘炎效果理想,在改善拇指疼痛及功能方面,效果明显优于传统中医手法,值得临床大力推广。

关键词：以筋为先四步理筋手法拇指狭窄性腱鞘炎