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Statement on Establishment of Public Health Protection Guideline for Cold Spells—China

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China CDC weekly 2024年第5期6卷 92-94页

作者： Tiantian li Qinghua Sun Chen Chen Qing Wang Jie Ban Runmei Ma Yi Zhang lijun Pan Yuanyuan liu qiutong li Leyao Chang Hanshuo Zhang Yirong liu Miaoyou Niu Xiangxiang Wei lin Wang China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

Cold spells are extreme weather events characterized by the invasion of cold air from high latitudes into the middle and low latitudes,resulting in significant *** spells have various adverse health effects,including epidermal damage,respiratory tract spasms,respiratory immune abnormalities,acute cardiopulmonary diseases,and exacerbation of urinary and endocrine *** response to the frequent cold spells in recent years.

关键词： respiratory invasion acute

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中草药添加剂在鱼类养殖中的应用研究进展

饲料工业 2024年第4期45卷 6-11页

作者：李秋潼王桂芹牛小天吉林农业大学动物科学技术学院吉林长春130118

随着我国鱼类养殖规模不断扩大,鱼类养殖的饲料添加剂受到广泛关注。中草药添加剂因其原料天然、毒副作用小、无污染等优点深受养殖户们的青睐,被广泛应用于鱼类养殖。文章通过对中草药添加剂的特点及应用等方面进行探讨,阐明中草药添... 详细信息

随着我国鱼类养殖规模不断扩大,鱼类养殖的饲料添加剂受到广泛关注。中草药添加剂因其原料天然、毒副作用小、无污染等优点深受养殖户们的青睐,被广泛应用于鱼类养殖。文章通过对中草药添加剂的特点及应用等方面进行探讨,阐明中草药添加剂在鱼类养殖中的作用和应用前景,以期为中草药添加剂在鱼类养殖中的应用提供指导。

关键词：中草药添加剂鱼类养殖特点功效促生长

基于GNSS的农机自动导航系统设计及路径规划

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测试技术学报 2024年第3期38卷 256-263页

作者：李秋潼刘宾中北大学信息与通信工程学院山西太原030051

针对目前农机智能化低、机械作业应用不充分的问题,设计了一种基于linux系统,通过图形化界面进行操作的农机自动导航系统,该系统使用全球导航卫星系统(Global Navigation Satellite System,GNSS)双定位定向模块解决了以往农机自动导航... 详细信息

针对目前农机智能化低、机械作业应用不充分的问题,设计了一种基于linux系统,通过图形化界面进行操作的农机自动导航系统,该系统使用全球导航卫星系统(Global Navigation Satellite System,GNSS)双定位定向模块解决了以往农机自动导航过程中航向不准、定位不稳的问题。依据山西省主要的环扣线耕作模式,在路径规划方面进行直线以及自动转弯路径算法设计。转弯路径航线使用四阶贝塞尔曲线进行优化,降低了农机及挂载机械的运行负荷。系统集成了角度采集的转向驱动模块,安装更便捷、性能更稳定。最后,以精拖奔野604拖拉机作为实验平台,进行了拖拉机的直线路径作业跟踪、转弯路径跟踪,经多次试验结果分析,得到的试验数据可满足田间实际作业的要求。

关键词：全球导航卫星系统定位数据采集农机导航路径规划

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锂离子电池内部信号监测技术概述

储能科学与技术 2024年第4期13卷 1253-1265页

作者：王玉婷李秋桐胡一鸣郭新华中科技大学材料科学与工程学院湖北武汉430074

锂离子电池在便携式电子产品、储能电站和电动汽车等领域得到了广泛的应用。然而,在电池容量不断上升的同时,锂离子电池的热失控风险也在增加,进而带来安全问题。现有的电池管理系统通过监测电池表面温度以及端电压来判断电池的健康状... 详细信息

锂离子电池在便携式电子产品、储能电站和电动汽车等领域得到了广泛的应用。然而,在电池容量不断上升的同时,锂离子电池的热失控风险也在增加,进而带来安全问题。现有的电池管理系统通过监测电池表面温度以及端电压来判断电池的健康状况。但是研究发现由于电池组件的多层结构和较差的导热性,电池内部温度、气体等很难散发到外部,导致对电池表面温度等外部信号的监测存在时效性差的问题。因此人们尝试直接监测电池内部温度、压力、应变和气体等信号的变化情况,实现及时预警电池热失控,增强锂离子电池在不同应用场景下的安全性。本文在理解热失控机制的基础上,概述了可以监测电池内部信号的方法。总结了锂离子电池在发生热失控时涉及的一系列放热反应,及在这些反应过程中电池内部温度、压力和气体等信号的变化情况。对于能够直接监测电池内部信号的技术,主要介绍了电化学阻抗分析和内置传感器监测,为以后优化监测方法提供参考信息。其中,将传感器植入到电池内部在实际应用中具有良好的前景。为了进一步提高锂离子电池系统的安全性,本文还对未来可能的研究方向进行了展望。

关键词：锂离子电池热失控内部信号监测和预警

Calibration of an elastoplastic model of sand liquefaction using the swarm intelligence with a multi-objective function

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 789-802页

作者： qiutong li Zhehao Zhu Shanghai Research Institute of Materials Shanghai200437China Shanghai Engineering Research Center of Earthquake Energy Dissipation Shanghai200437China Laboratoire Navier/Cermes École des Ponts ParisTechChamps-sur-Marne77455France

According to post-seismic observations,spectacular examples of engineering failures can be ascribed to the occurrence of sand liquefaction,where a sandy soil stratum could undergo a transient loss of shear strength and even behave as a“liquid”.Therefore,correct simulation of liquefaction response has become a challenging issue in geotechnical engineering *** advanced elastoplastic models of sand liquefaction,certain fitting parameters have a remarkable effect on the computed ***,the identification of these parameters,based on the experimental data,is usually intractable and sometimes follows a subjective trial-and-error *** this,this paper presented a novel calibration methodology based on an optimization algorithm(particle swarm optimization(PSO))for an advanced elastoplastic constitutive model.A multi-objective function was designed to adjust the global quality for both monotonic and cyclic triaxial *** overcome computational problem probably appearing in simulation of the cyclic triaxial test,two interrupt mechanisms were designed to prevent the particles from wasting time in searching the unreasonable space of candidate *** Dafalias model has been used as an example to demonstrate the main *** the calibrated parameters for the HN31 sand,the computed results were highly consistent with the laboratory experiments(including monotonic triaxial tests under different confining pressures and cyclic triaxial tests in two loading modes).Finally,an extension example is given for Ottawa sand F65,suggesting that the proposed platform is versatile and can be easily customized to meet different practical needs.

关键词： Particle swarm optimization(PSO) Sand liquefaction Elastoplastic constitutive model Triaxial test

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镀层结构对镀锌热成形钢表面颜色的影响

腐蚀与防护 2024年第8期45卷 50-55页

作者：卢岳孙力齐建军宋帅李秋瞳熊自柳河钢材料技术研究院石家庄050023

对镀锌22Mn B5钢板进行了不同工艺的热处理,分析了钢板表面镀层颜色的变化。通过扫描电子显微镜(SEM)、电子探针显微分析仪(EPMA)和辉光放电光谱仪(GDOES)等手段研究了镀层结构和镀层中元素迁移情况。结果表明:随着保温时间延长,镀层表... 详细信息

对镀锌22Mn B5钢板进行了不同工艺的热处理,分析了钢板表面镀层颜色的变化。通过扫描电子显微镜(SEM)、电子探针显微分析仪(EPMA)和辉光放电光谱仪(GDOES)等手段研究了镀层结构和镀层中元素迁移情况。结果表明:随着保温时间延长,镀层表面色差增大而亮度降低,在保温时间相同的情况下,890℃热处理温度下镀层的色差比880℃下的更大;镀层厚度为15~35μm,镀层中裂纹未深入至基体,组织为α-Fe(Zn)固溶体和Γ相;热处理过程中,锌和铁元素发生了扩散,表面氧化物层变厚,镀层中未观察到Fe-Zn金属间化合物,镀层厚度和表面粗糙度的增加以及表面氧化物的聚集共同导致了镀层表面色差和亮度的变化。

关键词：热成形钢色差辉光镀层结构氧化物元素扩散

Improved Methods for In-situ Measurement Railway Noise Barrier Insertion Loss

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第1期35卷 58-68页

作者： li qiutong Duhamel Denis Luo Yanyun Yin Honoré Université Paris-Est Laboratoire NavierENPC-IFSTTAR-CNRS Institute of Railway Transit Tongji University

Many countries which seek to understand the acoustic performance of railway noise barriers have established standards for the conduct of in-situ ***,there are no universally acknowledged receiver positions for the evaluation of the barrier performance,a fact which may be leading to uncertainty over the noise reduction capabilities of available *** terms of the descriptor of the barrier performance,the general recommendation is the A-weighted sound pressure level,although the latter is considered to underestimate low frequencies for railway noise ***,in this study,the comparison of receiver positions and the descriptors among existing Chinese,ISO and European standards were *** upon a combination of diffraction theory and standards,a rearrangement of receiver positions and one-third-octave-band analysis were *** addition,in line with improved methods,an in-situ measurement of insertion loss for a 1.5 mhigh railway noise barrier was designed and *** results of the experiment validate as effective and applicable the new receiver *** results also suggest that one-third-octave-band analysis is indispensable.

关键词： railway noise noise barrier in-situ experiment A-weighting insertion loss one-third-octave-band analysis grid receiver positions

空气净化干预对学龄儿童血压和心率的影响:一项整群的随机双盲交叉干预试验

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科学通报 2024年第17期69卷 2454-2462页

作者：李秋彤张翼方建龙孙庆华杜艳君王彦文雷剑朱毅翔薛晓薇陈仁杰阚海东李湉湉中国疾病预防控制中心环境与健康相关产品安全所北京100021 复旦大学公共卫生学院上海200032

空气颗粒物污染是心血管疾病发病和死亡的危险因素,儿童是脆弱人群之一.已有研究显示,室内安装使用空气净化设备可以降低颗粒物浓度,从而改善一般成年人群和老年人群心血管健康,但空气净化设备是否可有效改善儿童心血管健康尚无定论.为... 详细信息

空气颗粒物污染是心血管疾病发病和死亡的危险因素,儿童是脆弱人群之一.已有研究显示,室内安装使用空气净化设备可以降低颗粒物浓度,从而改善一般成年人群和老年人群心血管健康,但空气净化设备是否可有效改善儿童心血管健康尚无定论.为了评估空气净化设备使用对儿童血压和心率的影响,本研究基于学龄儿童开展干预周期长达4个月的整群随机双盲交叉干预试验,分别收集干预前和干预后的血压和心率测量数据、暴露数据和健康体检数据,利用双重差分模型进行统计分析,并进一步比较不同性别、体质指数和血压分层儿童间效应的差异.本研究共纳入79名平均年龄为10.6岁的学龄儿童,经过两阶段空气净化干预后发现,干预组教室和家庭内PM_(2.5)浓度低于室外,双重差分模型结果显示,空气净化干预后,儿童脉压差测量值显著降低3.44 mmHg(95%CI:−8.12~−0.11 mmHg).同时,分层分析结果显示,空气净化干预对不同性别和体质指数分层儿童血压和心率的影响存在显著差异.本研究相关结果可为空气净化干预改善儿童心血管健康提供证据,为空气污染相关的儿童心血管健康防护措施选择提供方向.

关键词：空气净化学龄儿童随机对照试验血压心率干预

Ambient fine particulate matter and cardiopulmonary health risks in China

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Chinese Medical Journal 2023年第3期136卷 287-294页

作者： Tiantian li Yi Zhang Ning Jiang Hang Du Chen Chen Jiaonan Wang qiutong li Da Feng Xiaoming Shi China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China

In China, the level of ambient fine particulate matter (PM_(2.5)) pollution far exceeds the air quality standards recommended by the World Health Organization. Moreover, the health effects of PM_(2.5) exposure have become a major public health issue. More than half of PM_(2.5)-related excess deaths are caused by cardiopulmonary disease, which has become a major health risk associated with PM_(2.5) pollution. In this review, we discussed the latest epidemiological advances relating to the health effects of PM_(2.5) on cardiopulmonary diseases in China, including studies relating to the effects of PM_(2.5) on mortality, morbidity, and risk factors for cardiovascular and respiratory diseases. These data provided important evidence to highlight the cardiopulmonary risk associated with PM_(2.5) across the world. In the future, further studies need to be carried out to investigate the specific relationship between the constituents and sources of PM_(2.5) and cardiopulmonary disease. These studies provided scientific evidence for precise reduction measurement of pollution sources and public health risks. It is also necessary to identify effective biomarkers and elucidate the biological mechanisms and pathways involved;this may help us to take steps to reduce PM_(2.5) pollution and reduce the incidence of cardiopulmonary disease.

关键词： Fine particulate matter Cardiopulmonary diseases Mortality Morbidity Risk factors