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Science China Earth Sciences 2011年第8期54卷 1199-1205页

作者： XIE DongHai GU XingFa CHENG TianHai YU Tao li zhengqiang CHEN XingFeng CHEN Hao GUO Jing State Key Laboratory of Remote Sensing Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences BeOing 100049 China

This paper retrieves the bidirectional polarization distribution functions (BPDFs) of the distinct urban cover in the Pearl River Delta (PRD) region employing the high spatial resolution of multi-angle polarized measurements made by the Directional Polarimetric Camera (DPC).The BPDF operational products of MICROPOL and POLDER measurements were used to validate the BPDF products of the DPC,with the results demonstrating that the BPDF product of the DPC measurements accurately expresses the surface polarized *** polarized reflectance of distinct surface types in the PRD region was studied using the DPC *** results demonstrate that the polarized reflectances of different surface types differ and decrease as the normalized difference vegetation index *** polarized reflectance of a distinct surface type in the PRD region decreases with increasing scattering *** basic theory of investigating surface properties using multi-angle polarized measurements is proposed.

关键词： Directional Polarimetric Camera bidirectional polarization distribution function aerosol POLDER normalized difference vegetation index MICROPOL

重庆市大足区≥60岁老年人健康素养水平及影响因素

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实用预防医学 2024年第4期31卷 479-483页

作者：李万华李正强任香勇杨颖胡邦伦重庆市大足区疾病预防控制中心重庆402360 重庆市大足区卫生健康委员会重庆402360

目的分析重庆市大足区≥60岁老年人健康素养水平及其影响因素,为制定老年人健康教育政策和措施提供参考依据。方法2022年在大足区4个镇/街道,采用多阶段整群随机和概率比例规模抽样法选择596名≥60岁常住居民进行问卷调查,数据采用SPSS ... 详细信息

目的分析重庆市大足区≥60岁老年人健康素养水平及其影响因素,为制定老年人健康教育政策和措施提供参考依据。方法2022年在大足区4个镇/街道,采用多阶段整群随机和概率比例规模抽样法选择596名≥60岁常住居民进行问卷调查,数据采用SPSS 25.0软件进行统计分析,不同人群健康素养水平的比较采用χ^(2)检验,其相关因素分析采用逐步后退的logistic回归分析。结果共计调查596人,平均年龄(71.69±6.03)岁。总体健康素养水平为17.11%。基本技能、老年人知识和理念、健康生活方式3方面健康素养水平分别为48.32%、19.97%和12.58%。6类健康问题素养水平由高至低依次为安全与急救(90.60%)、信息获取及自我保健(81.04%)、卫生服务利用及慢病管理(80.70%)、科学老龄观(31.88%)、健康生活方式(12.58%)、内在能力和老龄综合征(2.35%)。多因素logistic回归分析结果显示,城镇户口(OR=2.385,95%CI:1.300~4.376)、个人月收入≥3500元/月(OR=5.156,95%CI:1.536~17.305)、已签约家庭医生服务(OR=5.911,95%CI:2.242~15.587)、目前或退休前主要职业为未就业(OR=2.522,95%CI:1.202~5.292)有利于健康素养水平提升;目前或退休前主要职业为家务(OR=0.316,95%CI:0.125~0.796)对健康素养水平产生不利影响。结论大足区≥60岁老年人健康素养水平低,应对城乡、不同收入水平及不同职业的老年人开展针对性的健康教育和健康促进。

关键词：老年人健康素养影响因素

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基于公安移动信息网的云会商系统设计及应用

电视技术 2024年第5期48卷 26-30页

作者：明纪栋张夫全李正强翟奔山东省公安厅山东济南250001 华为技术有限公司广东深圳518000 合肥神州数码有限公司安徽合肥230001

探讨基于公安移动信息网的云会商系统设计及应用。首先介绍云会商系统的概况,其次详细阐述云会商系统的设计,包括系统架构、组成、功能、安全和可靠性等方面的设计;再次,介绍云会商系统的关键技术,包括云化虚拟化技术、多点控制单元(Mul... 详细信息

探讨基于公安移动信息网的云会商系统设计及应用。首先介绍云会商系统的概况,其次详细阐述云会商系统的设计,包括系统架构、组成、功能、安全和可靠性等方面的设计;再次,介绍云会商系统的关键技术,包括云化虚拟化技术、多点控制单元(Multipoint Control Unit,MCU)资源池化、会话初始协议(Session Initiation Protocol,SIP)和可伸缩视频编码(Scalable Video Coding,SVC)多流转发等;最后,探讨云会商系统的应用场景。

关键词：公安移动信息网云会商系统云计算资源池

Hot-melt extrusion promotes dissolution,extends“spring-parachute”process and inhibits crystallization in supersaturating microparticle systems

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Particuology 2023年第7期78卷 35-48页

作者： Yanfei Zhang Huifeng Zhang Huan Yu Yinghui Ma Chengyi Hao Xiaoying lin Yong Zhang zhengqiang li Xianrong Qi Jia Zeng Nianqiu Shi School of Pharmacy jilin Medical University Jilin132013jilin ProvinceChina Collge of life Science Jilin UniversityChangchun130012jilin ProvinceChina Department of Pharmaceutics School of Pharmaceutical SciencePeking UniversityBeijing100191China College of Pharmaceutical Sciences Yanbian UniversityYanji133002jilin ProvinceChina

Despite the potential advantages of amorphism-induced supersaturation,the merit of new amorphiza-tion formation methods on the properties of the amorphous drug including the stability of the amor-phous state,dissolution/solubility,supersaturation,and"spring-parachute"process is still poorly understood,particularly for certain amorphous supersaturating drug delivery systems(aSDDS).The present work aimed to explore the detailed merit of current attractive amorphization manufacturing methods(i.g.,hot-melt extrusion(HME)technique)on the property improvement of aSDDS in form of amorphous solid dispersion microparticles by employing a model Bcs II drug nitrendipine and a polyvinylpyrrolidone-based model polymer *** asDDS systems were developed by various methods,and their physicochemical properties were characterized by SEM,PXRD and ***-triggered amorphization induced superior supersaturation by the observation of the highest dissolution and *** induced the optimal supersaturation duration by the observed greatest extension of"spring-parachute"process(e.g,maximum AUCspring-parachute).HME technique is comparable with other techniques for the stabilization of amorphous state during *** aSDDS systems by HME and other methods showed improved long-term stability of the amorphous state in comparison to the pure amorphous *** transformation infrared spectroscopy,Noyes-Whitney equation,nucleation theory and Gibbs free energy of transfer(△G)were used to analyze the underlying ***-lecular mechanism studies indicated that HME caused a stronger crystallization inhibition effect in the asDDS systems than other methods,but molecular interaction is not a dominant mechanism for property enhancement caused by *** the mechanism associated with the polymer itself(PVPVA64),it could inhibit the drug recrystallization,solubilize the drug spontaneously and cause the improved molecular interactions in all aSDDS *** study provided

关键词： Hot-melt extrusion-triggered amorphization Extensionof"spring-parachute"process Promotion of dissolution/solubility Inhibition of crystallization from a supersaturated state Amorphism-based supersaturating drug microparticle systems

Baosteel's No.8 air separation unit and the practice of its system commissioning

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Baosteel Technical Research 2009年第3期3卷 23-26页

作者： ZHOU Chenhao CAI Lemin li zhengqiang Energy ＆ Environment Department Baoshan Iron ＆ Steel Co.Ltd. Shanghai 200941 China

This paper introduces the process flow, technical parameters and relevant features of Baosteel＇s No. 8 air separation unit （ASU） with a capacity of 60000m^3/h. It summarizes the commissioning work, which includes the adjustment of the air compressor,the system＇s naked cooling,the precooling system and the operation adjustment. It also provides detailed analyses on some failures which occurred in the commissioning. Through the modification of the design and the interlocks, the tripping probability of the air compressor was greatly reduced. Through the heating of the system and the control of the water cooler＇s nitrogen flow,the overproof content of carbon dioxide and fluctuation of oxygen flow were avoided. Nitrogen-block in the argon system was eliminated by the precise control of the argon rectification flow and argon content. All these solutions have been proved to be effective by practice.

关键词： air separation unit commissioning malfunction solution

Regional transport of anthropogenic pollution and dust aerosols in spring to Tianjin——A coastal megacity in China

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Regional transport of anthropogenic pollution and dust aeros...

Independent integration and innovation of the first domestically-integrated 60000 m^3/h air separation unit

第十五届海峡两岸气胶技术研讨会

作者： Xiaoli SU Junji CAO zhengqiang li Key Lab of Aerosol Chemistry & Physics Institute of Earth EnvironmentChinese Academy of Sciences State Environmental Protection Key Laboratory of Satellite Remote Sensing Institute of Remote Sensing and Digital EarthChinese Academy of Sciences

Simultaneous measurements of columnar aerosol microphysical and optical properties,as well as PM chemical compositions,were made during two types of spring pollution episodes in Tianjin,a coastal megacity of *** events were investigated using field observations,satellite data,model simulations,and meteorological *** lower ? ngstr?m Exponent and the higher Aerosol Optical Depth on 29 March,compared with the earlier event on 26 March,implied a dominance of coarse mode particles — this was consistent with the differences in volume-size *** on the single scattering spectra,the dominant absorber(at blue wavelength) changed from black carbon during less polluted days to brown carbon on 26 March and dust on 29 *** concentrations of major PM species for these two episodes also differed,with the earlier event enriched in pollution-derived substances and the later with mineral dust *** formation mechanisms of these two pollution episodes were also *** 26 March episode was attributed to the accumulation of both local emissions and anthropogenic pollutants transported from the southwest of Tianjin under the control of high pressure *** the high aerosol loading on 29 March was caused by the mixing of transported dust from northwest source region with local urban *** mixing of transported anthropogenic pollutants and dust with local emissions demonstrated the complexity of springtime pollution in *** synergy of multi-scale observations showed excellent potential for air pollution study.

关键词： Multi-scale observations urban pollution dust transport formation mechanism

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Baosteel Technical Research 2009年第3期3卷 3-12页

作者： YUAN Jilie QIAN Feng li zhengqiang GAO Yuan CHENG Yuzhi Energy ＆ Environment Department Baoshan Iron ＆ Steel Co.Ltd. Shanghai 200941 China

Baosteel＇s 60000 m……3/h air separation unit （ASU）, the first domestically-integrated unit of its class, is a milestone in the Chinese air separation industry. In this paper,the process characteristics of the unit and the application of the original techniques are expatiated. Some difficulties in the process design, the risk control, the quality control, the control system integration and the system commissioning are analyzed and appraised. The mode of the project integration and innovation, the cooperation among industries and the user-orientated project management mode are introduced. Finally,the successful experiences in innovation are summarized with the focus on the integration of the project.

关键词： air separation unit localization independent integration project management

基于改进型吸附等温线模型的空气预纯化TSA双层床模拟

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化工学报 2010年第10期61卷 2604-2614页

作者：张培昆王立李正强北京科技大学机械工程学院北京100083 上海宝山钢铁公司制氧厂上海201900

为了掌握空气中CO2和水蒸气在空分装置双层床变温吸附(TSA)纯化器中的动态吸附特性,通过LDF传质假设及非绝热假设,建立了一维二元稀组分系统的双层床TSA过程数学模型。一种改进型的多组分等温线模型用于描述水蒸气的Ⅱ型吸附等温线以及... 详细信息

为了掌握空气中CO2和水蒸气在空分装置双层床变温吸附(TSA)纯化器中的动态吸附特性,通过LDF传质假设及非绝热假设,建立了一维二元稀组分系统的双层床TSA过程数学模型。一种改进型的多组分等温线模型用于描述水蒸气的Ⅱ型吸附等温线以及水蒸气和CO2混合物的吸附平衡关系。通过对比模拟结果与TSA纯化器的现场监控数据发现,基于改进型等温线模型的模拟结果与现场数据吻合良好。最后对多种工况下的TSA纯化器中的温度、浓度及吸附量床层分布和穿透曲线进行了数值模拟和分析。

关键词：空气分离吸附等温线模型变温吸附纯化器

2000年—2018年中国和印度的长期PM2.5污染暴露的疾病负担研究

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遥感学报 2023年第8期27卷 1834-1843页

作者：朱玥石玉胜李正强中国科学院空天信息创新研究院北京100094 中国科学院大学电子电气与通信工程学院北京100049

PM_(2.5)作为空气污染物,对人体健康构成了潜在威胁。中国和印度是全球人口最多的两个发展中国家,PM_(2.5)污染造成的疾病负担问题尤为严重。因此,本文基于长时间序列高分辨率(0.01°×0.01°)卫星反演的PM_(2.5)浓度数据,分析了中国和... 详细信息

PM_(2.5)作为空气污染物,对人体健康构成了潜在威胁。中国和印度是全球人口最多的两个发展中国家,PM_(2.5)污染造成的疾病负担问题尤为严重。因此,本文基于长时间序列高分辨率(0.01°×0.01°)卫星反演的PM_(2.5)浓度数据,分析了中国和印度19年(2000年—2018年)的PM_(2.5)时空格局变化和人口暴露情况;基于综合暴露响应模型全面评估了两个国家因PM_(2.5)长期暴露导致的6种疾病(急性下呼吸道感染、慢性阻塞性肺病、二型糖尿病、缺血性心脏病、肺癌和中风)的过早死亡人数。结果表明,中国PM_(2.5)浓度的高值区集中在新疆、四川盆地、华北平原以及长江经济带等地区,年人口加权浓度总体呈减少趋势(2000年为50μg·m^(-3),2018年为40.8μg·m^(-3));印度PM_(2.5)浓度的高值区集中在北部地区,年人口加权浓度一直呈上升趋势(2000年为51.5μg·m^(-3),2018年为76.4μg·m^(-3))。对于中国而言,PM_(2.5)暴露造成的过早死亡人数从2000年的90.8万人增长至2018年的137.8万人,增长了47万人;中风是导致过早死亡的主要疾病终端,占总死亡人数的45.9%(56.3万人)。印度PM_(2.5)暴露造成的过早死亡人数从2000年的34.3万人增长至2018年的75万人,增长了40.7万人;缺血性心脏病和中风是导致过早死亡的主要疾病终端,分别占比39.9%(20.2万人)和25.5%(12.9万人)。研究结果有望为决策者和污染控制机构提供参考,有助于制定空气污染治理政策。

关键词：遥感 PM_(2.5) 疾病负担过早死亡中国印度长时序

Satellite remote sensing of atmospheric particulate matter mass concentration:Advances,challenges,and perspectives

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Fundamental Research 2021年第3期1卷 240-258页

作者： Ying Zhang zhengqiang li Kaixu Bai Yuanyuan Wei Yisong Xie Yuanxun Zhang Yang Ou Jason Cohen Yuhuan Zhang Zongren Peng Xingying Zhang Cheng Chen Jin Hong Hua Xu Jie Guang Yang Lv Kaitao li Donghui li State Environmental Protection Key Laboratory of Satellite Remote Sensing Chinese Academy of SciencesAerospace Information Research InstituteBeijing 100101China Key Laboratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai 200241China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Environment and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Satellite Application Center for Ecology and Environment Ministry of Ecology and EnvironmentBeijing 100835China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological AdministrationNational Satellite Meteorological CenterBeijing 10081China Universitéde lille CNRSUMR 8518LOA-Laboratoire d'Optique AtmosphériqueLille 59000France Chinese Academy of Sciences Anhui Institute of Optics and Fine MechanicsHefei 230031China

Mapping the mass concentration of near-surface atmospheric particulate matter(PM)using satellite observations has become a popular research niche,leading to the development of a variety of instruments,algorithms,and datasets over the past two *** this study,we conducted a holistic review of the major advances and challenges in quantifying PM,with a specific focus on instruments,algorithms,datasets,and modeling methods that have been developed over the past 20 *** aim of this study is to provide a general guide for future satellite-based PM concentration mapping practices and to better support air quality monitoring and management of environmental ***,we review the evolution of satellite platforms,sensors,inversion algorithms,and datasets that can be used for monitoring aerosol *** then compare various practical methods and techniques that have been used to estimate PM mass concentrations and group them into four primary categories:(1)univariate regression,(2)chemical transport models(CTM),(3)multivariate regression,and(4)empirical physical *** the main challenges encountered in PM mapping practices,for example,data gaps and discontinuity,a hybrid method is proposed with the aim of generating PM concentration maps that are both spatially continuous and have high precision.

关键词： Satellite remote sensing Particulate matter Aerosol optical depth Air quality monitoring Environmental modeling