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Particulate matter exchange between atmosphere and roads surfaces in urban areas

Journal of Environmental Sciences 2020年第12期32卷 118-123页

作者： Tong Wei Buddhi Wijesiri yingxia li Ashantha Goonetilleke State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Science and Engineering Faculty Queensland University of Technology(QUT)GPO Box 2434Brisbane4001QueenslandAustralia

The deposition and the re-suspension of particulate matter(PM) in urban areas are the key processes that contribute not only to stormwater pollution, but also to air pollution. However, investigation of the deposition and the re-suspension of PM is challenging because of the difficulties in distinguishing between the resuspended and the deposited PM. This study created two Bayesian Networks(BN) models to explore the deposition and the re-suspension of PM as well as the important influential factors. The outcomes of BN modelling revealed that deposition and re-suspension of PM10 occurred under both, high-traffic and low-traffic conditions, and the re-suspension of PM2.5 occurred under low-traffic conditions. The deposition of PM10 under low-volume traffic condition is 1.6 times higher than under highvolume traffic condition, which is attributed to the decrease in PM10 caused by relatively higher turbulence under high-volume traffic conditions. PM10 is more easily resuspended from road surfaces compared to PM2.5 as the particles which larger than the thickness of the laminar airflow over the road surface are more easily removed from road surfaces. The increase in wind speed contributes to the increase in PM build-up by transporting particulates from roadside areas to the road surfaces and the airborne PM2.5 and PM10 increases with the increase in relative humidity. The study outcomes provide a step improvement in the understanding of the transfer processes of PM2.5 and PM10 between atmosphere and urban road surfaces, which in turn will contribute to the effective design of mitigation measures for urban stormwater and air pollution.

关键词： Bayesian networks(BN) Particle build-up Particulate re-suspension Road surfaces

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A system dynamics urban water management model for Macao, China

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Journal of Environmental Sciences 2016年第12期28卷 117-126页

作者： Tong Wei Inchio Lou Zhifeng Yang yingxia li State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China. Department of Civil and Environmental Engineering University of Macao Macao 999078 China

Urban water resources have been facing significant pressure from population growth, urbanization, and climate change. A system dynamics urban water management model was proposed to simulate the dynamic interactions between urban water demands and society, economy, climate, and water conservation. The residents＇ water conseration willingness was incorporated in the model and water-saving effects were quantified. The simulation results for Macao showed that population size was the main driving force for urban water demand. The change of temperature and precipitation has obvious effects on the landscape water demand. The water demand output is sensitive to the change in population, per capita demand, and temperature. Increased precipitation will reduce urban water demand and increased economic growth will increase water demand. By implementing integrated water conservation measures and imoroved water conservation willinmaess, water demand could be reduced bv 17.5%.

关键词： Macao System dynamics Water conservation willingness Water demand

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Desulfurization of gasoline by condensation of thiophenes with formaldehyde in a biphasic system using aqueous phase of acids

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Chinese Journal of Chemical Engineering 2017年第2期25卷 166-170页

作者： Miao He yingxia li Jie Zhang Biaohua Chen State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Aqueous phase of acids as catalysts for the desulfurization of gasoline by condensation of thiophenes with form- aldehyde in a biphasic system was investigated. Two types of model gasoline with and without aromatics and olefins were employed in this work. The desulfurization rates were above 90% on these two types of model gasoline using formic acid and HaPW12O40 （0.8 mol·L-1）, indicating that the presence of aromatics and olefins has no effect on the desulfurization rate. High temperature （above 90 ℃） was more favorable to the process for desulfurization. Four hours was considered to be the proper treating time for the sulfur removal. In addition, aqueous phase of acids could be recycled at least 4 times without decreasing desulfurization rate. Finally, the possible process for the integration of condensation desulfurization into the existing refinery process for the production of gasoline with low sulfur content was proposed.

关键词： Desulfurizafion Condensation AcidThiophene

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Identification and quantification of lead source in sediment in the northern East China Sea using stable lead isotopes

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Journal of Oceanology and limnology 2021年第5期39卷 1887-1900页

作者： Yu YU yingxia li Bing li Yichao REN Xiaoyu DONG School of Marine Science and Engineering Qingdao Agricultural UniversityQingdao 266237China

Stable Pb isotopes in surface and core sediments were determined to identify the sources of Pb contaminants in the northern East China Sea(ECS).The Bayesian stable isotope mixing model was used to quantify the contributions of Pb *** results show that since the late 1980 s,ratios of^(207)Pb/^(206)Pb and^(208)Pb/^(206)Pb increased in the top 34-cm sediment shown in the coastal core samples,reflecting elevated anthropogenic Pb input in coastal *** increase of^(207)Pb/^(206)Pb and^(208)Pb/^(206)Pb ratios in surface sediments reveals that anthropogenic Pb came mainly via atmospheric transmission into the *** sources accounted for 12.0%-21.1%of the total Pb in sediments after the 1990 *** combustion was the largest anthropogenic contributor(47.5%±18.8%),and Pb mining and smelting,cement production,and vehicle exhaust/gasoline contributed 23.2%±7.1%,19.0%±13.0%,and 10.3%±6.9%,*** proportions of the anthropogenic sources gradually increased while geogenic source(riverine sediment)decreased from the coast to the outer *** study demonstrated that the significant influence of atmospheric input of Pb contaminants into the ECS,and also the urgent need to control coal combustion and Pb discharge from industrial dust and fume emission in *** also highlights the promising application of the Simmr model to quantify the proportions of multiple sources of trace elements in an environment.

关键词： lead contamination Bayesian stable isotope mixing model source quantification surface sediment core Changjiang River estuary

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ADDIE理念下护理实践教学中叙事能力培养的研究现状

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中国继续医学教育 2024年第5期16卷 191-195页

作者：李佯李迎霞孙国超大连医科大学附属第二医院脊柱外科辽宁大连116027 大连医科大学研究生院辽宁大连116044

随着医学模式的转换和医患矛盾的日渐突出,促使护理服务向着人性化、精细化、高质量的方向发展,临床护理实践教学是培养实习护生专业知识技能、沟通能力、评判性思维能力等综合能力的重要环节,培养实习护生的叙事能力,加强其人文关怀能... 详细信息

随着医学模式的转换和医患矛盾的日渐突出,促使护理服务向着人性化、精细化、高质量的方向发展,临床护理实践教学是培养实习护生专业知识技能、沟通能力、评判性思维能力等综合能力的重要环节,培养实习护生的叙事能力,加强其人文关怀能力对临床实习带教提出了更高的要求,也将面临更大的挑战,研究从ADDIE模式及叙事护理在国内外教学、培训领域中的应用及研究现状,指出目前我国护理实践教学模式存在的问题,结合本院护理实践教学的实际,对ADDIE理念下护理实践教学叙事能力培养在护理领域中的发展进行展望,提出进一步的思考,为护理管理者制定临床实习护生叙事能力培训策略提供参考,为ADDIE理念下的叙事护理在临床工作及教学中进一步应用推广提供借鉴。

关键词： ADDIE 护理实践教学叙事护理叙事能力人文关怀教学模式

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Bromodimethylsulfonium Bromide Catalyzed Synthesis of Methyl 2-Dexoy-4,6-O-benzylidene Galactopyranoside from Galactal and the Rapid Route to 2,3- and 2,6-Dideoxygalactopyranoses

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Chinese Journal of Chemistry 2012年第2期30卷 409-412页

作者： Ding,Ning Chun,Yuexing Zhang,Wei li,yingxia Department of Medicinal Chemistry Fudan University826 Zhangheng RoadShanghai 201203China School of Medicine and Pharmacy Ocean University of ChinaQingdaoShandong 266003China

4,6-O-Benzylidenation of D-galactal with PhCH（OCH3）2 catalyzed by bromodimethylsulfonium bromide leads to methyl 2-dexoy-4,6-O-benzylidene galactopyranoside efficiently, which serves as a key intermediate to the rea... 详细信息

关键词： deoxysugars bromodimethylsulfonium bromide synthetic methods galactal carbohydrate

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Desorption characteristics of total phosphorus and heavy metalsfrom impervious urban surface sediments

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Chinese Science Bulletin 2013年第27期58卷 3357-3360页

作者： li yingxia XIANG li TIAN Peng liU Jingling State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Dry sediments were collected from one roof and two roads in the central area of Beijing. The sediments were dry and wet sieved. The concentrations of total phosphorus (TP) and heavy metals were analyzed. The highest mass proportion of the dry sediments from the roads were between 125 and 300 μm in diameter, while the roof sediments were much smaller, with 75% of the total sediment mass between 40 and 74 μm in diameter. The concentrations of TP and heavy metals in the roof sediments were much higher than in the road sediments. The concentrations of the six heavy metals investigated had a similar order for all three sampling sites, with the Zn concentration always being the highest, followed by the Mn concentration, and the Ni concentration was always the lowest. After wet sieving, 76.9% to 91% of the TP in the sediments from the three sites remained in undesorbable particulate form, and 68.9% to 97% of the heavy metals were present in undesorbable particulate form. The concentrations of undesorbed heavy metals in the roof sediments tended to increase with increasing sediment size, but a similar trend was not found in the road sediments. This study shows that more attention should be given to the particulate matter in stormwater runoff, as reducing the amount of particulates will improve the efficiency of pollution control measures.

关键词：表层沉积物总磷特征和城市防渗解吸锌浓度重金属

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基于表情向量聚类的课堂交互学生推荐方法

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软件导刊 2024年第6期23卷 163-169页

作者：李慧张运良陈红倩李英侠中国科学技术信息研究所北京100038 北京联合大学管理学院北京100101 北京工商大学计算机学院北京100048

为了提升课堂提问环节交互学生的选择针对性,提出一种基于表情序列向量聚类的课堂交互学生个体推荐方法。首先,使用表情识别模型从学生端视频中获取表情向量,将每一名学生的所有表情向量汇总至教师端,并组合为表情向量序列;其次,基于学... 详细信息

为了提升课堂提问环节交互学生的选择针对性,提出一种基于表情序列向量聚类的课堂交互学生个体推荐方法。首先,使用表情识别模型从学生端视频中获取表情向量,将每一名学生的所有表情向量汇总至教师端,并组合为表情向量序列;其次,基于学生表情向量序列提出基于短期表情向量聚类的学生分类方法和基于长期表情向量聚类的学生推荐方法;最后,通过可视化和表格形式为教师呈现学生的分类和推荐结果,为教师快速选择不同类型中最突出的学生个体提供支持。通过教师评价发现,所提方法能有效表现学生的状态差异,可显著提升课堂交互中学生的判别效率与提问目的性。

关键词：推荐方法课堂交互表情向量序列数据可视化

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Is urban development an urban river killer? A case study of Yongding Diversion Channel in Beijing, China

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Journal of Environmental Sciences 2014年第6期26卷 1232-1237页

作者： Xi Wang Junqi li yingxia li Zhenyao Shen Xuan Wang Zhifeng Yang Inchio Lou State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing University of Civil Engineering and Architecture Department of Civil and Environmental Engineering University of Macao

The high population and concrete environment alter urban areas by changing temperature, rainfall runoff, and water resource utilization activities. This study was conducted to investigate the water quality features of the Yongding Diversion Channel in Beijing, China, and its relationship with rainfall and urban development. Monthly water quality data were obtained from April to October of 2004 at monitoring sites of Sanjiadian, Gaojing, Luodaozhuang, and Yuyuangtan. The monthly water quality grades from 2007 to 2011 were also investigated and compared with those of other rivers. Dissolved oxygen and pH showed greater decreases after one or two moderate rainfall events than several light rainfall events. The potassium permanganate index （CODMn）, ammonia nitrogen （NH3-N） and total phosphorus （TP） increased more after several light rainfall events than after one or two moderate or heavy rainfall events. Pollutant concentrations （CODMn, NH3-N, TP） in downstream regions showed greater changes than those in upstream areas after heavy rainfall events. Intense human activities around the channel greatly influenced the water quality of the channel in rainy season because of runoff pollution; however, heavy rainfall had a strong dilution effect on the pollutant concentrations in rivers. Overall, urban development has obviously deteriorated the water quality of the Yongding Diversion Channel as indicated by an increase in the water quality index from 3.22 in 2008 to 4.55 in 2010. The Pearson correlation between monthly rainfall and water quality indices from 2007 to 2011 ranged from 0.1286 to 0.6968, generally becoming weaker as rainfall and rainfall runoff became more random and extreme.

关键词： rainfallurban development water quality indices Yongding Diversion Channel

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Carcinogenesis of asbestos switched on by inducing cross-linkage between DNA complementary pair bases

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Chinese Science Bulletin 2002年第13期47卷 1086-1091页

作者： DAI Qianhuan CHEN Sha li yingxia Center of Environmental Science Peking UniversityBeijing 100871China Center for Chemistry and Bioengineering of Cancer Beijing Polytechnic UniversityBeijing 100022China

Since the beginning of the 1980s, Dai Qianhuan predicted based upon his di-region theory that the carcino-genesis switched on by the so-called physical carcinogenic factors including radiation, asbestos and foreign matter implantation, is just initiated through the cross-linking between DNA complementary pair bases induced by them. In this note, it was evidenced with the DNA filter elution method that the oxygenase activated by asbestos induces the cross-linking between DNA inter-strands and DNA-protein with dosage correlation, in which over 80% of DNA inter-strand cross-link ratio account for the total cross-link ratio. Obviously, both of the cross-linkages are just induced by hydroxyl free radical, HO·, because the ferrous ion increased the cross-link ratios up to several times through Fenton reaction and vitamin C inhibited the cross-link ratios with factors of 8-9 by destroying the hydroxyl radical. Non-carcinogen but with lower free radical formation energy, pyrene, by culturing with asbestos

关键词： asbestos mechanism of carcinogenesis di-region theory hydroxyl free radical DNA interstrand cross-link Fenton reaction AM1 molecular orbital calculation.

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