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China CDC weekly 2024年第36期6卷 934-938页

作者： Xi Wang rongfeng zhou Ting Li Shuai Du Ayan Mao Wuqi Qiu Hongzhou Lu Institute of Medical Information Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Infectious Diseases National Clinical Research Center for Infectious DiseasesThe Third People’s Hospital of ShenzhenShenzhen CityGuangdong ProvinceChina.

This study examines the socioeconomic and public health effects of a recent respiratory illness outbreak in northern China,focusing on Beijing following the lifting of coronavirus disease 2019(COVID-19)*** analyzes the implications of increased influenza A(H3N2)and Mycoplasma pneumoniae cases on urban health systems and economic *** mixed-methods study integrated a review of academic and governmental literature,a quantitative analysis of public health data,and a qualitative assessment of response *** indicate a significant increase in respiratory illnesses in late 2023,prompting a proactive response from health authorities that involved expanded hospital capacity and intensified ***,including resource limitations and public health fatigue,persisted,affecting response *** outbreak management was achieved through immediate health responses,although the event highlighted the need for improved infrastructure,surveillance,and policy *** emphasize the importance of international collaboration and comprehensive preparedness plans to strengthen global health security for future epidemics.

关键词： intensified lifting prompt

TA2纯钛热压缩过程中形变对相变与再结晶的影响

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稀有金属材料与工程 2024年第4期53卷 1120-1129页

作者：刘程祥黄东亚周荣锋刘昆李永坤殷新华文科张亚真昆明理工大学材料科学与工程学院云南昆明650093 云南钛业股份有限公司云南楚雄651209

使用Gleeble-1500热力学模拟实验机对TA2纯钛在相变点前后以10 s^(-1)的变形速率进行热压缩变形,研究热压缩对相变的影响。研究发现形变作用在相变点附近时,相变首先发生在板条之间,新形成的β晶粒多为球状或短棒状。随着压缩量的增大,... 详细信息

使用Gleeble-1500热力学模拟实验机对TA2纯钛在相变点前后以10 s^(-1)的变形速率进行热压缩变形,研究热压缩对相变的影响。研究发现形变作用在相变点附近时,相变首先发生在板条之间,新形成的β晶粒多为球状或短棒状。随着压缩量的增大,相邻的β晶核逐渐连接并变为条状组织。相变存在临界值,当压缩温度分别为860、890和920℃时,压缩量达到40%、30%和20%时,相变趋于饱和,取而代之的是动态再结晶的大量发生。温升效应对相变的影响不大,当变形量较大时温升效应相应提高,动态再结晶数目显著增多,而相变却几乎不发生。温度越高,形变促进相变的现象就越明显,当压缩温度在相变点之后时,很小的压缩量就可以使相变快速发生。

关键词：纯钛热压缩 EBSD 微观结构

Effects of C and Mn elements on deformation-enhanced ferrite transformation in low carbon (Mn) steels

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Journal of University of Science and Technology Beijing 2005年第6期12卷 507-511页

作者： rongfeng zhou Wangyue Yang Rong zhou Zuqing Sun Faculty of Mechanical and Electrical Engineering Kunming University of Science and Technology Kunming 650093 China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

Effects of C and Mn contents on the deformation-enhanced ferrite transformation （DEFT） in low carbon （Mn） steels have been investigated by hot compression. The microstructures of 2-4μm ultra-fine equiaxed ferrite grains with minors distributed homogeneously can be obtained by DEFT in all the tested steels. The more pronounced refinement is achieved as the C or Mn content increasing because of the higher-density nucleating sites and lower growth rate. The effectiveness of C on the level of refinement is more obvious than that of Mn.

关键词： deformation-enhanced transformation ferrite grain refinement low carbon steel manganese steel

变形量对半固态CuSn10合金组织和性能的影响

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稀有金属材料与工程 2024年第2期53卷 424-434页

作者：文科李永坤周荣锋殷新华熊文韬刘程祥张亚真昆明理工大学材料科学与工程学院云南昆明650093 昆明理工大学城市学院云南昆明650051

材料的组织形态直接影响零件的性能,采用自主研发的熔体约束诱导形核半固态制浆装置制备Cu Sn10半固态浆料并流变挤压成薄板,然后在350℃下轧制变形,研究变形量对微观组织和性能的影响。结果表明,随着变形量增加,变形板件内部缩松缩孔... 详细信息

材料的组织形态直接影响零件的性能,采用自主研发的熔体约束诱导形核半固态制浆装置制备Cu Sn10半固态浆料并流变挤压成薄板,然后在350℃下轧制变形,研究变形量对微观组织和性能的影响。结果表明,随着变形量增加,变形板件内部缩松缩孔等铸造缺陷逐渐减少减小、晶粒呈现压缩拉长趋势、平均晶粒厚度从初始未变形时30.58μm到变形量ε=0.4时的22.12μm。随变形量的加大在初生相内部产生的形变孪晶数量逐渐增加。在变形量从ε=0增加到ε=0.4的过程中,Cu Sn10合金组织内小角度晶界占比逐渐占优,引入了大量的亚结构和位错密度。在变形量ε=0.4时,可以发现极图{110}和{111}存在[101]、[111]和[001]织构。在板材力学性能方面,板材的屈服强度、抗拉强度和硬度不断增加;但塑性呈现下降的趋势。变形量ε=0.4时,其屈服强度、抗拉强度和布氏硬度(HBW)分别达到了443 MPa、554MPa、1901.2MPa,相较于初始未变形薄板其屈服强度、抗拉强度和硬度分别提高了106.1%、66.4%、41.6%,延伸率降低至0.82%。半固态Cu Sn10合金在变形过程中随变形量的增加强度、硬度不断提高、塑性持续降低,这主要是归功于在轧制变形过程中产生的晶粒细化和加工强化。

关键词：铜锡合金半固态轧制变形微观结构 EBSD

2018-2022年南京市公众预防接种相关舆情特征分析

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中国公共卫生 2024年第3期40卷 367-370页

作者：黄琦敏梁亚琼周荣锋李媛媛南京市疾病预防控制中心江苏210003通信作者:烫亚琼1

目的分析南京市公众预防接种相关舆情特征。方法从南京12 345政务热线平台和南京12 320健康服务平台收集2018-2022年预防接种相关工单1 525件,收集个案的工单编号、诉求时间、诉求渠道、诉求内容的详细信息,将信息录入EXCEL 2010软件... 详细信息

目的分析南京市公众预防接种相关舆情特征。方法从南京12 345政务热线平台和南京12 320健康服务平台收集2018-2022年预防接种相关工单1 525件,收集个案的工单编号、诉求时间、诉求渠道、诉求内容的详细信息,将信息录入EXCEL 2010软件形成数据库后分类汇总分析。结果 2018-2022年,南京市疾病预防控制中心共受理预防接种相关工单1 525件,平均月工单量为25.42件。2018年工单件数位列第1的为7月47件,占比78.33%;2019年工单件数位列第1的为6月和11月各7件,分别占比14.29%;2020年工单件数位列第1的为2月11件,占比20.00%;2021年工单件数位列第1的为8月227件,占比32.24%;2022年工单件数位列第1的为12月165件,占比25.11%。诉求内容涉及单品种疫苗种类位列前3的为新冠病毒疫苗1 128件,人乳头瘤病毒(HPV)疫苗103件和狂犬疫苗72件。2018-2022年新上市的疫苗中,带状疱疹疫苗85.71%的诉求内容为接种门诊地点,接种时间,预约接种流程,接种需要携带材料。新冠病毒疫苗此类诉求内容占比47.52%。结论疫苗质量安全问题,重大突发事件导致免疫服务暂缓,大规模接种的疫苗免疫程序调整可导致预防接种相关舆情数量短期出现较大波动。新上市疫苗主要诉求内容为如何接种到疫苗。

关键词：预防接种 12345政务服务热线 12320卫生热线舆情

The 4Rs approach to COVID-19 emergency management during the post-pandemic period:What lessons can be learned from Shenzhen,China?

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Infectious Medicine 2022年第4期1卷 272-275页

作者： rongfeng zhou Hongzhou Lu Department of Infectious Diseases National Clinical Research Center for Infectious Diseasesthe Third People’s Hospital of ShenzhenShenzhenChina

The Omicron variant of SARS-CoV-2(or Omicron)is extremely contagious and has swept the world in a short ***—a new international city in China with a permanent population of 17.56 million and covering nearly 2000 square kilometers—was attacked by Omicron in ***,the pandemic was controlled in a very short time as a result of prompt government reaction that prevented the variant’s further *** total number of cases in this wave of the pandemic was more than ***’s successful experience in tackling the Omicron wave deserves in-depth *** by American scholar Robert Heath,the 4Rs model aims to reduce the harm from a crisis through the measures of reduction,readiness,response,and *** article presents the successful experience of Shenzhen’s local government and the Third People’s Hospital of Shenzhen,the only hospital in Shenzhen designated to use the 4Rs emergency management model for the treatment of COVID-19 during the 2022 Omicron wave of the pandemic.

关键词： COVID-19 Omicron variant of SARS-CoV-2 Epidemic Shenzhen’s experience 4Rs

Electrochemical reduction characteristics and the mechanism of chlorinated hydrocarbons at the copper electrode

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Frontiers of Environmental Science & Engineering 2007年第2期1卷 207-212页

作者： XU Wenying GAO Tingyao zhou rongfeng MA Lumin The National Engineering Research Center for Urban Pollution Control Tongji UniversityShanghai 200092China

The electrochemical reduction characteristics of chlorinated hydrocarbons were investigated by cyclic voltam-metry *** reduction mechanism and activity of the chlorinated hydrocarbons at the copper electrode were *** relationship between the structure of chlori-nated hydrocarbons and their reductive activity were *** experimental results showed that chlorinated alkanes and a portion of chlorinated aromatic hydrocarbons could be reduced directly at the copper ***,chlorinated aromatic hydrocarbons were not easy to reduce at the copper *** results provided a theoretical basis for the catalyzed iron inner electrolysis method.

关键词： chlorinated hydrocarbons cyclic voltammetry electrochemical reduction copper electrode

Natural amber, copal resin and colophony investigated by UV-VIS, infrared and Raman spectrum

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1598-1602页

作者： RAO ZhiFan DONG Kun YANG XiaoYun LIN JinChang CUI XiaoYing zhou rongfeng DENG Qing Analysis and Testing Center of Yunnan Kunming University of Science and Technology School of Engineering and Applied Science Harvard University

Natural amber, copal resin and colophony are have investigated by UV-VIS, infrared and Raman spectrum. In order to distin- guish the natural amber, copal resin and colophony, we have successfully used the nondestructive examination （NDE） technology. The results show that UV-VIS could not distinguish these compositions. The infrared spectra can distinguish them, but the technology may destroy the specimen. The Raman spectra show three characteristic peaks of vibration near position 932 cmq and position 1179 cmq of copal resin, which confirm the existence of terpenes compounds in it. In the Raman spectra of colophony, the vibration characteristic peak at position 1589 cmq, caused by the conjugate double bond of internal unsaturated resin acid, is the basis of the characteristic difference between colophony and natural amber. The advantages of the distin- guished technology by Raman spectroscopy are convenient and nondestructive examination for natural amber, copal resin and colophony.

关键词： gemology nondestructive examination spectrum rosin

A target parameter estimation method via atom-reconstruction in radar mainlobe jamming

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Journal of Systems Engineering and Electronics 2024年第2期35卷 350-360页

作者： zhou Bilei LIU Weijian LI rongfeng CHEN Hui ZHANG Liang DU Qinglei LI Binbin CHEN Hao Air Force Early Warning Academy Wuhan 430019China Aerospace Nanhu Electronic Information Technology Co. Ltd.Jingzhou 434000China

Mainlobe jamming(MLJ)brings a big challenge for radar target detection,tracking,and *** suppression of MLJ is a hard task and an open problem in the electronic counter-counter measures(ECCM)*** parameters and target direction estimation is difficult in radar MLJ.A target parameter estimation method via atom-reconstruction in radar MLJ is proposed in this *** proposed method can suppress the MLJ and simultaneously provide high estimation accuracy of target range and ***,the eigen-projection matrix processing(EMP)algorithm is adopted to suppress the MLJ,and the target range is estimated effectively through the beamforming and pulse *** the target angle can be effectively estimated by the atom-reconstruction *** any prior knowledge,the MLJ can be canceled,and the angle estimation accuracy is well ***,the proposed method does not have strict requirement for radar array construction,and it can be applied for linear array and planar ***,the proposed method can effectively estimate the target azimuth and elevation simultaneously when the target azimuth(or elevation)equals to the jamming azimuth(or elevation),because the MLJ is suppressed in spatial plane dimension.

关键词： mainlobe jamming anti-jamming atom-reconstruction radar

倾斜板角度对亚共晶高铬铸铁半固态组织的影响

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特种铸造及有色合金 2006年第3期26卷 159-161页

作者：田琴周荣锋蒋业华周荣昆明理工大学

采用倾斜板冷却体法对亚共晶高铬铸铁进行半固态成形,研究了倾斜板角度对亚共晶高铬铸铁半固态组织的影响规律。结果表明:倾斜板角度过大或过小都将使得组织中的初生奥氏体较粗大、圆整度较小。当倾斜板角度较小时,金属液的流速相对较慢... 详细信息

采用倾斜板冷却体法对亚共晶高铬铸铁进行半固态成形,研究了倾斜板角度对亚共晶高铬铸铁半固态组织的影响规律。结果表明:倾斜板角度过大或过小都将使得组织中的初生奥氏体较粗大、圆整度较小。当倾斜板角度较小时,金属液的流速相对较慢,枝晶与枝晶和枝晶与金属液间的冲刷、碰撞、剪切作用较小,晶粒易于长大,导致枝晶状初生奥氏体比较多。当倾斜板角度较大时,金属液流速相对较快,金属液在倾斜板上流动的时间相对较短,枝晶间以及枝晶与金属液间的冲刷、碰撞、剪切作用时间相对较短,导致枝晶状初生奥氏体也比较多。当倾斜板角度为45°时,制备的亚共晶高铬铸铁初生奥氏体的尺寸最小,圆整度最高。

关键词：倾斜板角度冷却体法亚共晶高铬铸铁初生奥氏体