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Magnitude and direction of temperature variability affect hospitalization for myocardial infarction and stroke:population-based evidence from Guangzhou,China

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 1-11页

作者： Zhou Yang Murui Zheng Ze-Lin Yan Hui Liu Xiangyi Liu Jie-qi jin Jiagang Wu Chun-Quan Ou State Key Laboratory of Organ Failure Research Department of BiostatisticsGuangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical UniversityGuangzhou 510515China Guangzhou Center for Disease Control and Prevention Guangzhou 510440China

Relationships between nonoptimal temperatures and cardiovascular disease(CVD)mortality have been well ***,evidence of the association between temperature variability(TV)and CVD morbidity is *** study aimed to quantify the risk and burden of CVD-related hospitalization associated with the magnitude and direction of *** on meteorology and population-based hospitalizations for myocardial infarction(MI)and stroke were collected in Guangzhou,China,from 2013 to *** temperature variability(HTV)was measured as the standard deviation of hourly temperature records over specific exposure *** direction(upward or downward)of HTV was defined as the average daily mean temperature change relative to that of the previous day during the exposure ***-Poisson regression was applied to assess the impact of HTV after adjusting for the daily mean temperature,and the hospitalization fractions attributable to HTV were calculated.A 1℃-increase in HTV was significantly associated with a 2.24%and 1.72%increase in hospitalizations for MI and hemorrhagic stroke(HS)at lag 0–1 d,respectively,and a 1.55%increase in hospitalizations for ischemic stroke(IS)at lag 0–3 *** the study period,5.99%,4.64%,and 4.53%of MI,HS,and IS hospitalizations,respectively,were attributable to *** upward TV exerts acute effects on CVD hospital admissions,whereas the impact of downward TV generally *** findings highlight the importance of the magnitude and direction of temperature fluctuations,in addition to the mean level,in assessing the adverse health impacts of temperature variations.

关键词： Hourly temperature variability Cardiovascular Hospitalization Direction China

VSe_(2)/V_(2)C heterocatalyst with built-in electric field for efficient lithium-sulfur batteries:Remedies polysulfide shuttle and conversion kinetics

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Journal of Energy Chemistry 2024年第2期89卷 397-409,I0010页

作者： Yanwei Lv Lina Bai qi jin Siyu Deng Xinzhi Ma Fengfeng Han Juan Wang Lirong Zhang Lili Wu Xitian Zhang Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina

Lithium sulfur(Li-S)battery is a kind of burgeoning energy storage system with high energy ***,the electrolyte-soluble intermediate lithium polysulfides(Li PSs)undergo notorious shuttle effect,which seriously hinders the commercialization of Li-S ***,a unique VSe_(2)/V_(2)C heterostructure with local built-in electric field was rationally engineered from V_(2)C parent via a facile thermal selenization *** exquisitely synergizes the strong affinity of V_(2)C with the effective electrocatalytic activity of VSe_(2).More importantly,the local built-in electric field at the heterointerface can sufficiently promote the electron/ion transport ability and eventually boost the conversion kinetics of sulfur *** Li-S battery equipped with VSe_(2)/V_(2)C-CNTs-PP separator achieved an outstanding initial specific capacity of 1439.1 m A h g^(-1)with a high capacity retention of 73%after 100 cycles at0.1 *** impressively,a wonderful capacity of 571.6 mA h g^(-1)was effectively maintained after 600cycles at 2 C with a capacity decay rate of 0.07%.Even under a sulfur loading of 4.8 mg cm^(-2),areal capacity still can be up to 5.6 m A h cm^(-2).In-situ Raman tests explicitly illustrate the effectiveness of VSe_(2)/V_(2)C-CNTs modifier in restricting Li PSs *** with density functional theory calculations,the underlying mechanism of VSe_(2)/V_(2)C heterostructure for remedying Li PSs shuttling and conversion kinetics was *** strategy of constructing VSe_(2)/V_(2)C heterocatalyst in this work proposes a universal protocol to design metal selenide-based separator modifier for Li-S ***,it opens an efficient avenue for the separator engineering of Li-S batteries.

关键词： Li-S battery Shuttle effect Separator modifier VSe_(2)/V_(2)C heterostructure Built-in electric field

Improved Algorithm for Efficient Extraction of Relaxation Parameter Values from Wideband Permittivity of Baijiu

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Instrumentation 2024年第1期11卷 62-69页

作者： Haoyan Yu qi jin Zhaozong Meng Zhen Li College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China

The complex permittivity of baijiu varies with frequency,and dielectric spectroscopy has been used to evaluate the *** simplify the analysis and reduce the number of the parameters,a dielectric relaxation model is often used to fit the permittivity ***,existing fitting methods such as the least squares and particle swarm optimization methods are often computationally complex and require preset initial ***,a simpler calculation method of the relaxation parameters considering the geometric characteristics of the permittivity spectrum is *** is based on the relationship between the Cole-Cole relaxation parameters and the Cole-Cole diagram,which is fitted by a geometric ***,the concepts of the Cole-Cole parameters and the diagram are introduced,and then the process of obtaining the parameters from the complex permittivity measurement data is *** baijiu with 56%alcohol by volume(ABV)as an example,the fitting is better than the least squares method and similar to the particle swarm *** method is then used for the parameter fitting of baijiu with ABV of 42-52%,and the average error is less than 1%,demonstrating its wider ***,a prediction model is used for baijiu with 53%ABV,and the error is only 1.51%.Hence,the method can be applied to the measurement of ABV of baijiu.

关键词： permittivity cole-cole equation relaxation parameters alcohol by volume baijiu

LA-ICP-MS zircon U-Pb dating of tuffites in the Sachakou Pb-Zn mining area, Karakorum, Xinjiang and its establishment of Early Triassic strata

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China Geology 2024年第1期7卷 150-152页

作者： Xiao-jian Zhao Nuo Li Kai Weng Ming Wang qing-lin Sui Deng-hui Chen Zhou-ping Guo Meng-qi jin Xi’an Center China Geological SurveyMinistry of Natural ResourcesXi’an 710054China Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China College of Geography and Remote Sensing Sciences Xinjiang UniversityUrumqi 830046China University of Chinese Academy of Sciences Beijing 100029China No.8 Geological Party Xinjiang Bureau of Geology and Mineral Exploration and DevelopmentAksu 843000China School of Resource&Environment and Safety Engineering University of South ChinaHengyang 421001China

*** In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,*** are all located in the Mesozoic carbonate and clastic rock *** Sachakou leadzinc mining area is adjacent to the northwest of the Huoshaoyun lead-zinc mining area and is in the same stratigraphic layer as *** many scholars have been arguing about the type and age of Huoshaoyun lead-zinc mineralization,few scholars have paid attention to the classification of the ore-bearing strata in the *** stratigraphy of the Lower Permian Shenxianwan Group to the Upper Cretaceous Tielongtan Group is exposed in the Sachakou area of Karakorum,Xinjiang,however,the Late Permian-Early Triassic stratigraphy is missing(Fig.1a).Due to the harsh natural conditions in the area and the low level of work,the stratigraphic delineation is not exhaustive,and the regional lithology is dominated by carbonates and clastic rocks,which makes it difficult to identify the age of the regional lithology and causes problems for the exploration and research of lead-zinc in the area.

关键词： strata Triassic Xinjiang

基于时空最优低维动力系统的多尺度可压缩湍流数值模拟方法

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应用数学和力学 2024年第3期45卷 318-336页

作者：齐进吴锤结北京应用物理与计算数学研究所北京100088 大连理工大学力学与航空航天学院辽宁大连116024

按照周培源教授关于研究湍流数值模拟建模时必须分析和求解脉动速度场的思想,该研究基于第一性原理,系统地建立了基于时空低维最优动力系统的多尺度可压缩湍流数值模拟方法(LMS方法),并将其应用于多次冲击Richtmyer-Meshkov问题的数值... 详细信息

按照周培源教授关于研究湍流数值模拟建模时必须分析和求解脉动速度场的思想,该研究基于第一性原理,系统地建立了基于时空低维最优动力系统的多尺度可压缩湍流数值模拟方法(LMS方法),并将其应用于多次冲击Richtmyer-Meshkov问题的数值模拟中,首次得到了可压缩湍流的中尺度流场和不同于DNS近似解的湍流近似解.数值结果表明,LMS方法可以用较少的网格获得更精确的湍流近似解.首先解决了研究中遇到的几个问题,为LMS方法的构建铺平了道路.这些问题是:基于湍流的物理特性,提出了湍流大、中、小尺度分解的新概念;找到了box滤波空间相关性的计算方法;指出了湍流建模理论中长期存在的逻辑错误,提出了多尺度湍流模型的概念;讨论了湍流封闭问题的本质和关键,给出了克服湍流封闭问题的数值方法.采用box滤波方法/空间网格平均方法且在大尺度网格的意义下,LMS方法的本质是一种将RANS、LES、DES和DNS等湍流数值模拟方法统一的全新湍流数值模拟方法.需要指出的是,LMS方法也可以作为湍流模型研究的辅助工具,以检验SGS尺度方程/脉动方程中各项所对应的湍流模型是否正确.

关键词：周培源对湍流研究的开拓性贡献时空最优低维动力系统 LMS方法多尺度湍流模型可压缩湍流

第三方水质检测机构建设WOT分析与运维优化

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中国给水排水 2024年第14期40卷 36-41页

作者：农晋琦深圳市宝安排水有限公司广东深圳518000 深圳市宝排水质检测中心有限公司广东深圳518000

随着国家环境治理的深入发展,政府监管提出治污企业需提供经资质认定的公正检测数据的要求,并逐步走向法制化、常态化,中型排水国企综合考虑成本、业务量及盈亏等因素,面临自行出资建设第三方实验室还是外委检测的“两难”选择。基于SWO... 详细信息

随着国家环境治理的深入发展,政府监管提出治污企业需提供经资质认定的公正检测数据的要求,并逐步走向法制化、常态化,中型排水国企综合考虑成本、业务量及盈亏等因素,面临自行出资建设第三方实验室还是外委检测的“两难”选择。基于SWOT分析,以深圳市某中型排水国企改制的某排水公司水质检测中心为例,对其改制以及随后的经营运维等进行了研究探讨,提出了战略选择意见、建议和运维优化对策。分析结果表明,中型排水国企出资设立第三方水质检测机构,具有依托国企母公司、商业信誉良好、业务来源稳定可靠等优势,总体来说机遇大于威胁,优势大于劣势。本项目的过程分析与相关结论,可为同行开展相关项目提供一定的借鉴。

关键词：中型排水国企第三方水质检测机构 SWOT分析运维优化

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土壤中全硫测定——硫分析仪选择及方法优化

中国土壤与肥料 2024年第3期 240-246页

作者：晋琪汪洪北方干旱半干旱耕地高效利用全国重点实验室中国农业科学院农业资源与农业区划研究所国家化肥质量检验检测中心(北京)农业农村部农产品质量安全肥料源性因子风险评估实验室(北京)北京100081

全硫含量是土壤调查项目中的必测项目。在燃烧法直接测定固体样品的硫分析仪中,高频红外碳硫仪检测限低,检测速度快,燃烧温度高,测定土壤标准物质的准确度高,是快速测定土壤中全硫的最佳仪器。应用高频红外碳硫仪测定样品过程中,坩埚空... 详细信息

全硫含量是土壤调查项目中的必测项目。在燃烧法直接测定固体样品的硫分析仪中,高频红外碳硫仪检测限低,检测速度快,燃烧温度高,测定土壤标准物质的准确度高,是快速测定土壤中全硫的最佳仪器。应用高频红外碳硫仪测定样品过程中,坩埚空白、通氧流量、样品称样量、助熔剂添加量、定量方法等均会对测定结果准确度产生影响。通过对上述影响条件进行优化,研究确定了测定土壤中全硫含量的最佳条件:在严格控制坩埚空白的前提下,通氧流量设定为2~3 L/min,依次称取0.1 g样品(精度:0.0001 g)、0.5 g纯铁(精度:0.001 g)和1.0 g钨粒助熔剂(精度:0.001 g)混合后上机分析,对不同浓度样品进行分段校正。值得注意的是,本研究证实了利用化学物质标准品建立工作曲线的可行性,为后期仪器优化和改进提供了宝贵思路。国家土壤标准物质测定结果的相对标准偏差(RSD)小于2%(n=6),测定值与标准值相对误差(RE)的绝对值小于1%(n=6),方法检出限为4.50μg/g,说明方法的准确度和精密度高,适用于低含硫量土壤样品的批量检测。

关键词：硫含量土壤高频红外碳硫仪最佳条件

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与45钢对摩材料干摩擦条件下的摩擦学性能

高分子材料科学与工程 2024年第2期40卷 115-123页

作者：张金鹏张玮炜齐瑾王小静朱丽慧金健上海大学机电工程与自动化学院上海200444 上海大学材料科学与工程学院上海200444 上海船舶设备研究所上海200031

为选择与45钢对摩的摩擦副材料以适应干摩擦苛刻工况,采用RTEC多功能摩擦试验机,对超高分子量聚乙烯(UHMWPE)、改性聚醚醚酮树脂(改性PEEK)、浸渍呋喃树脂碳石墨(M120K)和浸渍巴氏合金碳石墨(M120B)4种配副材料的摩擦学性能进行测试,并... 详细信息

为选择与45钢对摩的摩擦副材料以适应干摩擦苛刻工况,采用RTEC多功能摩擦试验机,对超高分子量聚乙烯(UHMWPE)、改性聚醚醚酮树脂(改性PEEK)、浸渍呋喃树脂碳石墨(M120K)和浸渍巴氏合金碳石墨(M120B)4种配副材料的摩擦学性能进行测试,并利用扫描电子显微镜对磨损表面进行观察和分析,从微观角度揭示了4种材料的摩擦磨损机理。结果表明,随着载荷和转速的增加,平均摩擦系数大致呈现出M120B

关键词： 45钢对摩材料干摩擦摩擦系数磨损机理

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数智时代中华优秀传统文化教育的探索

教育参考 2024年第5期 37-41页

作者：金琪上海市西南位育中学上海200233

学校教育面临着如何在数智时代引导青少年传承和创新中华优秀传统文化的挑战。文章基于上海市西南位育中学在数智时代用中华优秀传统文化立德树人的实践和思考经验,提出学校教育中优秀传统文化的三个基本价值。用优秀传统文化中的重要... 详细信息

学校教育面临着如何在数智时代引导青少年传承和创新中华优秀传统文化的挑战。文章基于上海市西南位育中学在数智时代用中华优秀传统文化立德树人的实践和思考经验,提出学校教育中优秀传统文化的三个基本价值。用优秀传统文化中的重要元素研发学生喜闻乐见的数字化产品,介绍目标立体化、内容序列化、方法主体化、途径一体化、管理全员化等育人路径,探索数智时代的中华传统文化传承与创新之道。

关键词：数智时代中华优秀传统文化学校教育