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Simulation of people's evacuation in tunnel fire 被引量:5
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作者 杨高尚 彭立敏 +1 位作者 张进华 安永林 《Journal of Central South University of Technology》 EI 2006年第3期307-312,共6页
The simulation model Tunev(tunnel evacuation) was developed for people's evacuation in tunnel fire. It contains simple database of the people's behavioral reaction and structure characteristic parameters of tunnel... The simulation model Tunev(tunnel evacuation) was developed for people's evacuation in tunnel fire. It contains simple database of the people's behavioral reaction and structure characteristic parameters of tunnel fireproofing. The model can be used to calculate the total evacuation time in various scenes when fire occurs in the different locations of the tunnel. Combined with fire simulation soft ware CFD- POENICS3.5, Tunev model can be used to calculate the fire danger coming time; by comparing with these two kinds of time, it can be used to assess the safety of the evacuation, and the evacuation process also have a dynamic demo. The simulation results show that the Tunev model can be used to predict the reliability of safe evacuation for people in tunnel fire and provide references for people's safe escape scheme. Some relevant concepts of the model were described and an evacuation simulation of a typical tunnel case, i.e. Xuefeng Mountain Tunnel was performed by using this model. And the model's validation and actual aoolication were also described. 展开更多
关键词 tunnel fire people's evacuation simulation model
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老年人互联网使用如何影响代际同住——基于CLASS数据的研究
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作者 朱铭来 王本科 《人口与发展》 北大核心 2025年第2期105-115,共11页
在人口老龄化加剧与互联网迅速发展的背景下,互联网对老年人居住安排方式的影响亟待明确。基于2016—2020年中国老年社会追踪调查数据,采用面板Logit模型、工具变量法和倾向得分匹配法,实证研究了老年人互联网使用对其代际同住安排的影... 在人口老龄化加剧与互联网迅速发展的背景下,互联网对老年人居住安排方式的影响亟待明确。基于2016—2020年中国老年社会追踪调查数据,采用面板Logit模型、工具变量法和倾向得分匹配法,实证研究了老年人互联网使用对其代际同住安排的影响。研究表明老年人互联网使用会显著降低代际同住的可能性。这一影响主要通过改变个体禀赋和思想观念发挥作用,在基本养老保障水平较高、城市户籍及受儒家文化影响较弱的老年群体中更加显著,呈现明显的群体异质性。此外,不同类型的互联网活动对代际同住的影响也存在差异。上述发现有助于深入理解互联网时代老年人居住安排方式的变迁趋势,对制定针对性的养老政策具有参考价值。 展开更多
关键词 互联网使用 代际同住 养老禀赋 养老观念
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Study of Product Quality Information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept
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作者 RUAN Jin-yuan 1, SUN Shu-tao 2, YU Xin-qi 2, RUAN Xin 3 (1. Ordance Institute of General Equipment Department, Shijiazhuang 05 0000, China 2. Graduate School of Chinese Academic of Science, Beijing 100042, China +1 位作者 3. East China University of Science and Technology, Shanghai 200232, China 4. Meterology Bureau of Hebei Province, Shijiazhuang 050021, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期234-235,共2页
The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deep... The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of China and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:1.the type of quality information;2.the content of quality information;3.the construction of the se nsitive web for transfering information, and collecting and transfering quality information rapidly and effectively;4.the way and procedure to transfer informa tion;5.the construction of quality information library for all phases; 6.the d isposal of quality information;7.the decision making support system of the mana gement of quality information;8.attach importance to three key factors on impro ving quality concept. 展开更多
关键词 product guality information decision-making sup port system of management of guality information peoples guality concept
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第10期1029-1029,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第2期176-176,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第7期744-744,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第4期376-376,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第9期932-932,共1页
Aims and scope of the Journal. Medical Journal of Chinese People’s Liberation Army (Med J Chin PLA) is a multiple-subjects medical periodical published by the People’s Military Medical Press, under the auspice of De... Aims and scope of the Journal. Medical Journal of Chinese People’s Liberation Army (Med J Chin PLA) is a multiple-subjects medical periodical published by the People’s Military Medical Press, under the auspice of Department of Health, General Logistics Department of PLA, and it is issued domestically and abroad. Med J Chin PLA has become one of the source journals of statistics in Chinese Scientific Thesis and Chinese Scientific Quotation Database, the key periodical of multiple-subject medical journals, and is a prize journal of National Periodical Award and one of the Top Hundred Periodicals in China. Med J Chin PLA is issued monthly. Its permanent sections include Expert Forum, Research on Special Topics, Medical Treatises, Experimental Research, Clinical Research, Technology and Methodology, Discussion of Knotty Cases (Pathology), Reviews, Military Medical Sciences, News in Medicine etc. Manuscripts sent by both domestic and overseas writers are welcome. Contribution of reviews is usually invited by the Editors, but recommendations for topics and authors are welcomed. 展开更多
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2008年第7期918-918,共1页
Aims andscope of the Journal .Medical Journal of Chinese People’s Liberation Army (Med J Chin PLA) is a multiple-subjects medical periodical published by the People’s Military Medical Press,under the auspice of Depa... Aims andscope of the Journal .Medical Journal of Chinese People’s Liberation Army (Med J Chin PLA) is a multiple-subjects medical periodical published by the People’s Military Medical Press,under the auspice of Department ofHealth, General Logistics Department of PLA,andit is issued 展开更多
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2008年第1期120-120,共1页
Aims andscope of the Journal.Medical Journal of Chinese People's Liberation Army(Med J Chin PLA)is a multiple-subjects medical periodical published by the People's Military Medical Press,under the auspice of D... Aims andscope of the Journal.Medical Journal of Chinese People's Liberation Army(Med J Chin PLA)is a multiple-subjects medical periodical published by the People's Military Medical Press,under the auspice of Department of Health,General Logistics Department of PLA,and it 展开更多
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2006年第3期278-278,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Medical Journal of Chinese People′s Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2008年第6期784-784,共1页
关键词 s Liberation Army INsTRUCTIONs TO AUTHORs Medical Journal of Chinese people
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Development of antiinflammatory agents and immunopharmacology in the People’s Republic of China
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《中国药理学通报》 CAS CSCD 北大核心 1989年第5期-,共7页
With the rapid advance of academic activities in the field of phar-macology,antiinflammatory and immunopharmacology has become abranch of pharmacology in our country.Under professor Zhou Jin-huang’s charge and concer... With the rapid advance of academic activities in the field of phar-macology,antiinflammatory and immunopharmacology has become abranch of pharmacology in our country.Under professor Zhou Jin-huang’s charge and concerns,the first national conference of anti-inflammatory and immunopharmacology was held at Huang Shan in1982.In following years,the frist training class for antiinflamma-tory and immunopharmacological studies was conducted in Hefei. 展开更多
关键词 Development of antiinflammatory agents and immunopharmacology in the people s Republic of China
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Medical Journal of Chinese People's Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2007年第2期178-178,共1页
关键词 Medical Journal of Chinese peoples Liberation Army INsTRUCTIONs TO AUTHORs
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Medical Journal of Chinese People's Liberation Army INSTRUCTIONS TO AUTHORS
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《解放军医学杂志》 CAS CSCD 北大核心 2008年第8期1048-1048,共1页
Aims andscope of the Journal .Medical Journal of Chinese People’s Liberation Army ( Med J Chin PLA) is a multiple-subjects medical periodical publishedby the People’s Military Medical Press,under the auspice of Depa... Aims andscope of the Journal .Medical Journal of Chinese People’s Liberation Army ( Med J Chin PLA) is a multiple-subjects medical periodical publishedby the People’s Military Medical Press,under the auspice of Department of Health, General Logistics Department of PLA,andit 展开更多
关键词 Medical Journal of Chinese peoples Liberation Army INsTRUCTIONs TO AUTHORs
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基于核心素养的人教版七年级生物学新教材HPS材料分析
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作者 赵婷婷 《天津师范大学学报(基础教育版)》 北大核心 2025年第2期56-61,共6页
HPS(科学史、科学哲学与科学社会学)材料可用于体现生物学核心素养。人教版七年级生物学新教材共包含26则HPS材料,新增多则材料,凸显了科学精神与科学家精神。研究认为:新教材调整了材料呈现位置与内容,促进核心概念建构与核心素养培养... HPS(科学史、科学哲学与科学社会学)材料可用于体现生物学核心素养。人教版七年级生物学新教材共包含26则HPS材料,新增多则材料,凸显了科学精神与科学家精神。研究认为:新教材调整了材料呈现位置与内容,促进核心概念建构与核心素养培养,具有丰富的育人价值。教师要深入分析新教材,灵活使用这些HPS材料,以情境导入激发学习动机,以单元教学促进概念建构,以经典实验培养科学思维与探究能力,以多元化的活动落实课程思政。 展开更多
关键词 HPs 核心素养 人教版新教材 初中生物学
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湿气环境中CO_(2)-H_(2)S在α-Fe(110)密排面上吸附与点蚀机理研究
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作者 李金灵 马文骏 +2 位作者 朱世东 屈撑囤 付安庆 《表面技术》 EI CAS CSCD 北大核心 2024年第20期82-93,共12页
目的从微观尺度探究CO_(2)-H_(2)S(CO_(2)和H_(2)S共存)在湿气管道顶部的吸附特性,进而揭示点蚀机理。方法基于密度泛函理论的第一性原理,利用Materials Studio构建CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)密排面的吸附模型,对CO_(2)... 目的从微观尺度探究CO_(2)-H_(2)S(CO_(2)和H_(2)S共存)在湿气管道顶部的吸附特性,进而揭示点蚀机理。方法基于密度泛函理论的第一性原理,利用Materials Studio构建CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)密排面的吸附模型,对CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)面的吸附能、局域态密度、分波态密度和差分电荷密度进行仿真;利用高温高压釜模拟CO_(2)-H_(2)S-Cl^(-)腐蚀环境,分析L360钢在湿气环境中的腐蚀行为;最后,揭示含Cl^(-)湿气管道顶部CO_(2)-H_(2)S吸附机制与点蚀机理。结果CO_(2)、H_(2)S、CO_(2)-H_(2)S及CO_(2)-H_(2)S-Cl^(-)在最稳定位置时的吸附能分别为-4.065、-3.961、-8.538、-12.775e V,表明相较于CO_(2)与H_(2)S单独吸附,CO_(2)-H_(2)S在α-Fe(110)面的吸附能更负,Cl^(-)会进一步降低CO_(2)-H_(2)S的吸附能;且CO_(2)在与H_(2)S竞争环境电子中占优势;Cl^(-)会使CO_(2)-H_(2)S的局域态密度峰值降低,转移趋势为失去电子,基体和腐蚀介质的电子向着低能级跃迁释放出更多能量,进而加强了Fe与CO_(2)-H_(2)S间的化学键强度;Cl^(-)的2p轨道与Fe的3d轨道在-6.8 eV和-5.7 eV发生重叠,Cl^(-)被吸附到Fe表面并与Fe形成化学键生成氯化物,进而改变腐蚀产物膜的组分与结构,削弱产物膜的致密性和稳定性,减弱腐蚀阻抗力。在含Cl^(-)湿气的CO_(2)-H_(2)S环境中,液相中的Cl^(-)浓度升高,使L360钢的气相平均腐蚀速率逐渐增大,最高达2.935mm/a,点蚀越发严重。结论CO_(2)与H_(2)S在α-Fe(110)面吸附存在一定的协同和竞争作用,协同促进金属的腐蚀,FeCO3会优先沉积成膜,但H_(2)S会抑制FeCO3的生长,腐蚀产物以FeS为主;Cl^(-)会增强CO_(2)-H_(2)S与α-Fe(110)面间的作用力,弱化腐蚀产物膜层的保护性,进一步加速金属腐蚀、尤其是点蚀。 展开更多
关键词 CO_(2)-H_(2)s Cl^(-) 第一性原理 α-Fe(110)密排面 吸附特征 腐蚀机理
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H_(2)S在Cr(111)面上吸附与解离的第一性原理研究 被引量:1
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作者 江佐禹 黄本生 +1 位作者 何子涛 罗霞 《原子与分子物理学报》 CAS 北大核心 2024年第2期9-14,共6页
采用了第一性原理研究了H_(2)S在Cr(111)面的吸附解离过程,利用吸附能、吸附构型和偏态密度图(PDOS)研究了H_(2)S及其解离产物在Cr(111)面上的吸附情况,都偏向倾斜吸附在Cr(111)面.同时研究了HS/H和S/H共吸附情况,得到共吸附物质在Cr(1... 采用了第一性原理研究了H_(2)S在Cr(111)面的吸附解离过程,利用吸附能、吸附构型和偏态密度图(PDOS)研究了H_(2)S及其解离产物在Cr(111)面上的吸附情况,都偏向倾斜吸附在Cr(111)面.同时研究了HS/H和S/H共吸附情况,得到共吸附物质在Cr(111)面上有明显的相互作用.最后使用线性同步和二次同步变换方法确定了解离反应的过渡态,了解到第一、二步解离的活化能分别为1.65 eV、0.82 eV,H_(2)S分子在Cr(111)面上的解离过程是放热反应,反应能为-2.90 eV. 展开更多
关键词 H_(2)s Cr(111) 吸附 解离 第一性原理
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用于低浓度H_(2)S室温稳定监测的CsPbBr_(3)@TiO_(2)异质结微晶气体传感器
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作者 逯江浩 黄胜 +4 位作者 陈露 程永超 高莎莎 陶雪钰 顾修全 《人工晶体学报》 CAS 北大核心 2024年第10期1815-1826,共12页
通过简单的溶液法用TiO(Acac)_(2)原位包覆CsPbBr_(3)全无机钙钛矿材料,在400℃加热后直接制成了CsPbBr_(3)@TiO_(2)核壳结构微晶,使用X射线衍射(XRD)、扫描电子显微镜(SEM)、高倍透射电子显微镜(HRTEM)及X射线光电子能谱(XPS)对CsPbBr_... 通过简单的溶液法用TiO(Acac)_(2)原位包覆CsPbBr_(3)全无机钙钛矿材料,在400℃加热后直接制成了CsPbBr_(3)@TiO_(2)核壳结构微晶,使用X射线衍射(XRD)、扫描电子显微镜(SEM)、高倍透射电子显微镜(HRTEM)及X射线光电子能谱(XPS)对CsPbBr_(3)@TiO_(2)微晶的晶体结构、微观形貌、化学组成进行表征。结果表明,原位金属氧化物包覆钙钛矿形成分散良好、大小为4~8μm的球壳结构。用旋涂法在掺氟氧化锡(FTO)电极上构筑了CsPbBr_(3)@TiO_(2)薄膜气体传感器,在室温下测试其对H_(2)S气体的检测灵敏度,结果发现,该传感器对H_(2)S气体的检测下限达25 ppb(1 ppb=10-9),对100 ppb H_(2)S响应/恢复时间为24/21 s,灵敏度为0.59,响应曲线具有良好的循环稳定性。另外,传感器暴露在空气中30 d内的稳定性高于90%,且具有优异的气体选择性和抗湿度干扰性。通过光致发光(PL)光谱、时间分辨光致发光(TRPL)光谱、紫外-可见漫反射光谱(UV-Vis)及紫外光电子能谱(UPS)测试分析了其能带位置、电荷动力学和配位机理,并用氧吸附原理对其传感机理进行了解释。该工作为室温下低浓度H_(2)S气体的稳定监测提供了一种新的思路。 展开更多
关键词 CsPbBr_(3) 钙钛矿 核壳结构 异质结 H_(2)s气体传感器 氧吸附原理
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H_(2)S在五边形BCN上的吸附与解离的第一性原理计算研究
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作者 史金磊 时俊仙 +2 位作者 付龙 赵高 王丽丽 《原子与分子物理学报》 CAS 北大核心 2024年第1期59-63,共5页
基于密度泛函理论的第一性原理计算方法,研究了H_(2)S分子在五边形BCN上的吸附与解离过程.研究结果表明,五边形BCN结构的B原子是H_(2)S分子的最稳定的活性吸附位点. H_(2)S分子在该活性位点极易解离,其初步解离过程为放热反应且分解势... 基于密度泛函理论的第一性原理计算方法,研究了H_(2)S分子在五边形BCN上的吸附与解离过程.研究结果表明,五边形BCN结构的B原子是H_(2)S分子的最稳定的活性吸附位点. H_(2)S分子在该活性位点极易解离,其初步解离过程为放热反应且分解势垒仅为0.208 eV,并形成稳定的HS/H产物.深入研究发现,H_(2)S分子初步解离后的五边形BCN表面,可直接分解后续吸附的H_(2)S分子.该研究结果为五边形BCN对H_(2)S分子的吸附解离机制提供理论借鉴,并且首次提出五边形BCN可作为功能性材料净化有害气体H_(2)S的理想候选者. 展开更多
关键词 五边形BCN H_(2)s吸附解离 第一性原理计算
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