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Strengthened Monitoring of H5 Avian Influenza Viruses in External Environment in Hubei, 2018

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Current Medical Science 2020年第1期40卷 63-68页

作者： Lin-lin LIU Bin FANG Xiao YU Xiang LI Ya-ke LEI Dan CHEN institute of health inspection and testing Hubei Provincial Center for Disease Control and PreventionWuhan 430079China Wuhan University of Science and Technology Wuhan 430065China

The contamination status of H5 avian influenza viruses and distribution of subtypes of H5N1 and H5N6 in poultry-related environment of Hubei areas were *** and rural live poultry markets,poultry farms,intensive livestock farms and other monitoring types of 103 counties in 17 cities were selected in *** samples from cage surface,wiping samples from chopping board,fecal specimens and other environmental samples were collected and tested by real-time RT-PCR using primers and probes of influenza A,avian influenza of H5,N1 and N6 from December 2017 to March *** avian influenza virus positive rate was compared among different monitoring sites,samples,time and ***,7132 environmental samples were collected in 1634 monitoring points with a positive rate of 2.24%.The positive rate of H5 avian influenza virus was the highest in urban and rural live poultry markets(3.44%,x^2=61.329,P<0.05)in 6 monitoring sites and wiping samples from chopping board(5.46%,x^2=67.072,P<0.05)in 6 sample types.H5N6 avian influenza viruses were detected more in eastern than western Hubei,and H5N6 avian influenza viruses were detected only in Xiangyang city of western *** were important high-risk places of human infection with H5 avian influenza virus in urban and rural live poultry markets and the poultry slaughtering plants.H5N6 has been the predominant subtype of H5 avian influenza viruses in the eastern and western Hubei and H5N6 avian influenza viruses were still present in a few areas of *** of human H5N1 and H5N6 avian influenza remain at risk in Hubei province.

关键词： H5 avian influenza virus external environment strengthened monitoring

A quantitative research on the level of disturbance to secondary signal ports of electronic voltage transformers under the operation of gas‐insulated switchgear

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High Voltage 2022年第1期7卷 165-175页

作者： Qi Wang Chao Fu Fanwu Chu Yue Tong Xiaozhou Wang Guoxiong Ye Xiong Wu Power Industry Electrical Equipment Quality inspection and testing Center China Electric Power Research InstituteWuhanChina

The collectors of electronic transformers has the problem of electromagnetic in-compatibility under the operation of disconnecting switches,which limits their wide application in smart *** evaluate the maximum level of disturbance that collectors are able to withstand in the stochastic process of switching operation,this work in-troduces a quantitative approach based on limited test measurements,which can quantify the level of disturbance in the signal acquisition ports of electronic voltage transformers(EVT)in different gas‐insulated switchgears(GIS).Based on large numbers of experi-mental statistical data of the true type simulation experimental platform,the Spearman rank correlation coefficient is used to prove that the amplitude of the disturbance voltage pulse at the secondary side port and the breakdown voltage between the primary side fracture approximately satisfy a linear ***,the quantile regression model is used to quantify and verify the maximum disturbance level of the secondary side ***,a solution is proposed to tackle the difficulty in obtaining the breakdown voltage at breaks in the GIS substation field applicatvion,under which the quantified maximum disturbance voltage deviation of secondary ports is only−4.34%by *** research work can further explore the practical value of the measured data in a few tests under GIS substation field conditions and provide references for the sub-sequent revision of EVT‐related standards.

关键词： disturbance operation electronic

Effects of "Products of Chicken Embryo" on Growth and Sexual Development in Rats

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Biomedical and Environmental Sciences 1999年第2期12卷 125-135页

作者： WU CHUAN-JIN AND DAI YIN(institute of Food Control and inspection, Ministry of health, Chinese Academy of Preventive Medicine, Beijing 100021, China) institute of Food Control and inspection Ministry of Health Chinese Academy of Preventive Medicine Beijing China

Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepard from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1. 2 %, 3 %, 12%, and 48%, respectively) by gavage up to their onsets of *** rats in the control group were treated with distilled water. However, Ji-Pei-Jing treatment exerted some effects on sexual mauration in the immature female rats. Essentially, the effects showed a dose-response tendency with an inverted 'U' *** age of vopnal opening for gnup treated with Ji-Pei-Jing was significantly earier than that to the control. Its uterus weight/b. w. ratio also significantly increased on day 30 and at the first estrus. There were significantly increases in the adrenal weight/b. w. raio of 30-day-old rats that were treated with 3%, 12%, and 48% Ji-Pei-Jing. The rats treated with 48% Ji-Pei-Jing had significantly lesser ovary weight.b.w. radio on day 30, too. The rats treated with Ji-Pei-Jing could normally ovulate at the first estrus, and no significant differences were observed during estrous *** effects of PCE on serum levels of K, P, LH in 30-day-old nds and FSH in 28-day-old ras were elevated significantly by 3 % Ji-Pei-Jing treatment. It appeare that the effects of PCE result from interaction of contained complex physiologically active substances. Steriods, especially estradio-17β,possibly Play a key role, and polpeptide hormones may also exert important effects.

关键词： Effects of Products of Chicken Embryo on Growth and Sexual Development in Rats LHRH

Effect of stress profile on microstructure evolution of cold-drawn commercially pure aluminum wire analyzed by finite element simulation

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Journal of Materials Science & Technology 2018年第7期34卷 1214-1221页

作者： Y.K.Zhu Q.Y.Chen Q.Wang H.Y.Yu R.Li J.P.Hou Z.J.Zhang G.P.Zhang Z.F.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences National Quality Supervision & inspection Center of Electrical Equipment Safety Performance Zhejiang Huadian Equipment Testing Institute

The evolution of microstructure in the drawing process of commercially pure aluminum wire （CPAW） does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CPAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of 〈111〉 texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the 〈111 〉 texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CPAW under axial loading.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Commercially pure aluminum wire Cold drawing Texture Finite element simulation Stress profile

Interaction Between Ustilaginoidea virens and Rice and Its Sustainable Control

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Rice science 2024年第3期31卷 269-284页

作者： ZHANG Fengmin CAO Zhenzhen ZHENG Xin HE Yuntao CHEN Mingxue LIN Xiaoyan Rice Product Quality inspection&Supervision testing Center of Ministry of Agriculture and Rural Affairs China National Rice Research InstituteHangzhou 310006China

Ustilaginoidea virens is a common rice pathogen that can easily lead to a decline in rice quality and the production of toxins pose potential risks to human *** this review,we present a comprehensive literature review of research since the discovery of rice false *** provide a comprehensive and,at times,critical overview of the main results and findings from related research,and propose future research ***,we delve into the interaction between *** and rice,including the regulation of transcription factors,the process of *** infecting rice panicles,and the plant immune response caused by rice *** that,we discuss the identification and characterization of mycotoxins produced by the pathogenic fungus,as well as strategies for disease *** emphasize the importance of comprehensive agricultural prevention and control methods for the sustainable management of *** knowledge will update our understanding of the interaction between *** and rice plants,offering a valuable perspective for those interested in ***.

关键词： rice false smut flower-specific infection mycotoxin food safety plant disease

Effects of boronizing treatment on microstructural development and mechanical properties of additively manufactured TC4 titanium alloys

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Journal of Iron and Steel Research International 2019年第3期26卷 329-334页

作者： Jin-zhu Song Wei Tang Jie-wen Huang Zi-kang Wang Xin-min Fan Ke-hong Wang College of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina Jiangsu Product Quality testing&inspection institute Nanjing 210007JiangsuChina

Microstructure and mechanical properties of additively manufactured TC4 alloys were investigated,following boronizing *** treatment process was carried out at temperatures ranging from 950 to 1050°C and held for 8-15 *** microstructural features of fabricated boride layers were examined by optical *** phase compositions of the boride layers were analyzed by X-ray *** hardness profile through the boride layers was also *** results showed that the boride layer of additively manufactured TC4 had a thickness of 51 pm and was composed of an outer TiB2 layer on the top of TiB layer;TiB whiskers wedged into the matrix,forming a strong bond between the boride layer and *** diffusion activation energy was determined to be 80.9 kJ/*** matrix was found to transfer from needlelikeα'martensite phase toα+βbiphasic *** newly formed boride layer can reach 1680 HV in hardness,thus imparting a strong protection to 3D-printed part.

关键词： Additive manufacturing TC4 titanium alloy Boronizing Microstructure Microhardness

Investigation of the segregation of a binary particle mixture in a square circulating fluidized bed with air staging

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Particuology 2019年第6期17卷 70-76页

作者： Mingkun Du Shuai Wang Guangdong institute of Special Equipment inspection and Research Zhuhai Inspection InstituteZhuhai 519002China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

To further understand the segregation characteristics of a binary particle mixture in a riser,the flow behaviors of particles with different sizes were experimentally and numerically investigated in a cold square circulating fluidized *** impact of the gas velocity,solid circulation rate,initial coarse particle fraction,and air staging on the coarse particle fraction and axial pressure drop were *** experimental results show that air staging can significantly promote the pressure drop of a binary mixture at the bottom of the bed compared with that of monosized ***,the segregation of the binary mixture at the bottom is *** was also found that there was clear radial segregation owing to a higher coarse particle fraction near the wall compared with the bed's center and its corner.

关键词： Circulating fluidized bed Binary mixture Segregation Air staging

Technical progress of China’s national remote sensing mapping:from mapping western China to national dynamic mapping

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Geo-Spatial Information Science 2021年第1期24卷 121-133,I0013页

作者： Jixian Zhang Haiyan Gu Wei Hou Chunquan Cheng National Quality inspection and testing Center for Surveying and Mapping Products State BeijingChina Chinese Academy of Surveying and Mapping BeijingChina

Remote sensing mapping is an important research direction in the development of geographic surveying and *** order to successfully implement the project of Mapping Western China(MWC),a technical mapping system has been *** this project,many problems have been solved through technological innovation,such as block adjustment with scarce control points,large-scale aerial/satellite image mapping,and intelligent interpretation of multi-source *** softwares were developed,*** for aerial/satellite image mapping in a large area,FeatureStation for the integration of multi-source data in the complex terrain areas,and an airborne multi-band and multi-polarization interferometric data acquisition system for SAR *** the first time,full coverage of 1:50,000 topographic data of China’s land territory has been produced,which means the geospatial framework of digital China is basically *** the implementation of other key national plans and projects(*** geographic conditions monitoring and national remote sensing mapping),the focus has changed from MWC to national dynamic ***,a dynamic mapping system is *** data acquisition capability has developed from a single source to multiple sources and multiple *** mapping capability has developed into dynamic mapping,and the capability for database update shows the characteristics of *** national geographic condition monitoring creates a multi-scale index system for statistical analysis for various needs.A multi-level and multi-dimensional technical system for statistical computing and decision-making service is developed for the transformation from dynamic monitoring to information *** this paper,we give a brief introduction about the recent development of remote sensing mapping in China with respect to data acquisition,map production,and information *** purpose of this paper is to motivate the establishment

关键词： Remote sensing mapping mapping western China national dynamic monitoring data acquisition image interpretation information service

Attenuation of ground vibrations due to different technical sources

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 337-344页

作者： L.Auersch S.Said Federal institute of Material Research and testing

The attenuation of technically induced surface waves is studied theoretically and experimentally. In this paper, nineteen measurements of ground vibrations induced by eight different technical sources including road and rail traffic, vibratory and impulsive construction work or pile driving, explosions, hammer impulses and mass drops are described, and it is shown that the technically induced ground vibrations exhibit a power-law attenuation v - r ~ where the exponents q are in the range of 0.5 to 2.0 and depend on the source types. Comparisons performed demonstrate that the measured exponents are considerably higher than theoretically expected. Some potential effects on ground vibration attenuation are theoretically analyzed. The most important effect is due to the material or scattering damping. Each frequency component is attenuated exponentially as exp（-kr）, but for a broad-band excitation, the sum of the exponential laws also yields a power law but with a high exponent. Additional effects are discussed, for example the dispersion of the Rayleigh wave due to soil layering, which yields an additional exponent of 0.5 in cases of impulsive loading.

关键词： wave attenuation environmental vibrations field tests material damping scattering damping Rayleigh wave