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Emission factors of polycyclic aromatic hydrocarbons from domestic coal combustion in China

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Journal of Environmental Sciences 2014年第1期26卷 160-166页

作者： Chunmei Geng Jianhua Chen Xiaoyang Yang Lihong Ren baohui Yin Xiaoyu Liu Zhipeng Bai State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences

Domestic coal stove is widely used in China, especially for countryside during heating period of winter, and polycyclic aromatic hydrocarbons （PAHs） are important in flue gas of the stove. By using dilution tunnel system, samples of both gaseous and particulate phases from domestic coal combustion were collected and 18 PAH species were analyzed by GC-MS. The average emission factors of total 18 PAH species was 171.73 mg/kg, ranging from 140.75 to 229.11 mg/kg for bituminous coals, while was 93.98 mg/kg, ranging from 58.48 to 129.47 mg/kg for anthracite coals. PAHs in gaseous phases occupied 95% of the total of PAHs emission of coal combustion. In particulate phase, 3-ring and 4- ring PAHs were the main components, accounting for 80% of the total particulate PAHs. The total toxicity potency evaluated by benzo[a]pyrene-equivalent carcinogenic power, sum of 7 carcinogenic PAH components and 2,3,7,8-tetrachlorodibenzodioxin had a similar tendency. And as a result, the toxic potential of bituminous coal was higher than that of anthracite coal. Efficient emission control should be conducted to reduce PAH emissions in order to protect ecosystem and human health.

关键词： domestic coal combustion emission factor polycyclic aromatic hydrocarbons potential toxicity risk diagnostic ratio

Chemical characteristics of road dust PM2.5 fraction in oasis cities at the margin of Tarim Basin

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Journal of Environmental Sciences 2020年第9期32卷 217-224页

作者： Hao Yu Xueyan Zhao Jing Wang baohui Yin Chunmei Geng Xinhua Wang Chao Gu Lihua Huang Wen Yang Zhipeng Bai College of Water Sciences Beijing Normal UniversityBeijing 100875China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China The Xinjiang Uygur Autonomous Region environmental monitoring station Xinjiang 830011China College of Resources and Environment Linyi UniversityShandong 276000China

In order to understand the compositions characteristics of particulate matter with aerodynamic diameter less than 2.5μm(PM2.5)fraction in road dust(RD2.5)of oasis cities on the edge of Tarim Basin,30 road dust(RD)samples were collected in Kashi,Cele,and Yutian in the spring,2018,and RD2.5 was collected using the resuspension approach.Eight watersoluble ions,39 trace elements and 8 fractions of carbon-containing species in PM2.5 were analyzed.Ca2+and Ca were the most abundant ions and elements in RD2.5(7.1%and 9.5%).Cl-in RD2.5 was affected not only by attributed to saline-alkali soils in oasis cities of the Tarim Basin and dust from Taklimakan Desert but also by human activities.Moreover,the organic carbon/elemental carbon(OC/EC)ratio indicated that carbon components in RD2.5in Cele town mainly come from fossil fuel combustion,while those in Yutian and Kashi mainly come from biomass combustion.It is noteworthy that high Ca in RD2.5 was seriously affected by anthropogenic emissions,and high Na and K contents in RD2.5 could be derived from soil and desert dust.It was estimated that Cd,Tl,Sn and Cr were emitted from anthropogenic emissions using the enrichment factor.The coefficients of divergence(cOD)result indicated that the influence of local emission on road dust emission is greater than that of long-distance transmission.This study is the first time to comprehensively analyze the chemical characteristics of road dust in oasis cities,and the results provides the sources of road dust at the margin of Tarim Basin.

关键词： dust characteristics Tarim

Vertical distribution of volatile organic compounds conducted by tethered balloon in the Beijing-Tianjin-Hebei region of China

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Journal of Environmental Sciences 2020年第9期32卷 121-129页

作者： Chunmei Geng Jing Wang baohui Yin Ruojie Zhao Peng Li Wen Yang Zhimei Xiao Shijie Li Kangwei Li Zhipeng Bai State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Tianjin Eco-Environmental Monitoring Center Tianjin 300191China

Volatile organic compounds(VOCs) as precursors of ozone and secondary organic aerosols can cause adverse effects on the environment and human health.However,knowledge of the VOC vertical profile in the lower troposphere of major Chinese cities is poorly understood.In this study,tethered balloon flights were conducted over the juncture of BeijingTianjin-Hebei in China during the winter of 2016.Thirty-six vertical air samples were collected on selected heavy and light pollution days at altitudes of 50-1000 meters above ground level.On average,the concentration of total VOCs(TVOCs) at 50-100 m was 4.9 times higher than at 900-1000 m(46.9 ppbV vs.8.0 ppbV).TVOC concentrations changed rapidly from altitudes of 50-100 to 401-500 m,with an average decrease of 72%.With further altitude increase,the TVOC concentration gradually decreased.The xylene/benzene ratios of 34/36 air samples were lower than 1.1,and the benzene/toluene ratios of 34/36 samples were higher than 0.4,indicating the occurrence of aged air mass during the sampling period.Alkenes contributed most in terms of both OH loss rate(39%-71%) and ozone formation potential(40%-72%),followed by aromatics(6%-38%).Finally,the main factors affecting the vertical distributions of VOCs were local source emission and negative dispersion conditions on polluted days.These data could advance our scientific understanding of VOC vertical distribution.

关键词： pollution balloon ozone

基于偏联系数的大兴区地下水水质时空动态演变趋势分析

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水资源保护 2023年第2期39卷 233-243页

作者：门宝辉李晨尹世洋华北电力大学水利与水电工程学院北京102206

为探究城镇化对大兴区浅层地下水水质的影响,采用大兴区2006—2016年浅层地下水水质数据,选择硝酸盐、总硬度、溶解性总固体(TDS)3个水质指标作为评价指标,基于ArcGIS的空间插值和区域分析工具,按照行政边界提取区域水质结果,通过集对... 详细信息

为探究城镇化对大兴区浅层地下水水质的影响,采用大兴区2006—2016年浅层地下水水质数据,选择硝酸盐、总硬度、溶解性总固体(TDS)3个水质指标作为评价指标,基于ArcGIS的空间插值和区域分析工具,按照行政边界提取区域水质结果,通过集对分析确定各区域的地下水水质等级,基于偏联系数对大兴区地下水水质动态演化规律进行评价分析。结果表明:硝酸盐指标主要涉及Ⅰ~Ⅳ类水,总硬度指标主要涉及Ⅲ~Ⅴ类水,TDS指标主要涉及Ⅲ、Ⅳ类水;研究区地下水水质等级呈现缓慢增长的趋势,水质出现恶化趋势;从空间分布上看,大兴区北部地下水综合水质等级和基于TDS指标的水质等级最高、南部次之、中部最低,基于硝酸盐指标的水质等级北部最高、中部次之、南部最低,基于总硬度指标的水质等级南部最高、中部次之、北部最低;基于各指标的水质Ⅱ级支持度均为最高,2013—2016年综合水质和基于总硬度指标、TDS指标的水质Ⅲ级支持度高于Ⅰ级支持度,相应水质有恶化的趋势,基于硝酸盐指标的水质Ⅰ级支持度高于Ⅲ级支持度,说明大兴区基于硝酸盐指标的整体水质有好转的趋势,但北部相应水质呈现持续恶化的趋势。

关键词：地下水水质空间变异偏联系数硝酸盐总硬度溶解性总固体大兴区

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数控车床在型钢轧辊孔型加工中的应用

山西冶金 2022年第2期45卷 278-279,284页

作者：尹宝慧秦皇岛市国阳钢铁有限公司河北秦皇岛066000

根据型钢轧辊的结构特点、装配形式以及加工技术要求等,分析了普通轧辊车床在轧辊加工中存在的各种问题和数控车床加工轧辊的各种优势,并介绍了数控车床在型钢轧辊孔型加工中的改造和实际应用,秦皇岛市国阳钢铁有限公司充分利用数控加... 详细信息

根据型钢轧辊的结构特点、装配形式以及加工技术要求等,分析了普通轧辊车床在轧辊加工中存在的各种问题和数控车床加工轧辊的各种优势,并介绍了数控车床在型钢轧辊孔型加工中的改造和实际应用,秦皇岛市国阳钢铁有限公司充分利用数控加工技术的优势,实现了型钢轧辊高质量、高效率的加工要求。

关键词：型钢轧辊数控车床孔型加工应用

基于减法集对势的大兴区地下水开采强度评价与诊断

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水资源保护 2022年第5期38卷 17-25,57页

作者：门宝辉李晨尹世洋华北电力大学水利与水电工程学院北京102206

为定量评价大兴区地下水开采强度,识别引起地下水开采强度增加的主要因素,基于集对分析构建了地下水开采强度评价模型,对研究区2006—2016年地下水开采强度进行了动态评价,并利用减法集对势识别了影响地下水开采强度的主要因子。结果表... 详细信息

为定量评价大兴区地下水开采强度,识别引起地下水开采强度增加的主要因素,基于集对分析构建了地下水开采强度评价模型,对研究区2006—2016年地下水开采强度进行了动态评价,并利用减法集对势识别了影响地下水开采强度的主要因子。结果表明:研究区2006—2016年地下水平均开采强度为中等强度,且有逐步恶化的趋势;2010年、2013年地下水开采强度平均联系数的减法集对势分别处于偏反势、反势,是地下水开采强度重点调控的年份;2010年有3个指标联系数的减法集对势处于偏反势或反势,分别为工业产值、第三产业产值和水浇地面积,涉及乡镇分别为3个、3个、5个,2013年有5个指标联系数的减法集对势处于偏反势或反势,分别为水浇地面积、菜田面积、设施农业面积、果园面积、机井数,涉及乡镇分别为5个、3个、7个、1个、4个。

关键词：地下水开采强度地下水保护减法集对势联系数大兴区

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基于偏联系数的地下水开采强度动态评价研究

水资源与水工程学报 2022年第1期33卷 22-30,38页

作者：门宝辉李晨尹世洋华北电力大学水利与水电工程学院北京102206

为减少人类活动对地下水环境的影响,实现地下水资源可持续利用,需从时空尺度上对地下水开采强度进行动态评价。基于集对分析构建了地下水开采强度时空动态评价模型,并基于二阶偏联系数挖掘了同一度、差异度、对立度的动态演化过程,识别... 详细信息

为减少人类活动对地下水环境的影响,实现地下水资源可持续利用,需从时空尺度上对地下水开采强度进行动态评价。基于集对分析构建了地下水开采强度时空动态评价模型,并基于二阶偏联系数挖掘了同一度、差异度、对立度的动态演化过程,识别了影响地下水开采强度等级的主要因素。结果表明:2006-2016年,北京市大兴区地下水开采强度趋于增大,空间分布上中部地区>南部地区>北部地区;人口数、工业产值、第三产业产值对地下水开采强度等级影响的时空分布特征为北部地区>中部地区>南部地区。农业种植面积、机井数对地下水开采强度等级影响的时空分布特征为南部地区>中部地区>北部地区。依据二阶偏联系数识别结果,人口数、工业产值、第三产业产值对地下水开采强度的影响程度在增强,农业种植面积、机井数对地下水开采强度的影响程度在减弱。本文构建的地下水开采强度时空动态评价模型能够较好地反映研究区的地下水开采强度等级及动态演化过程,且计算简便,有一定的应用推广价值。

关键词：地下水开采强度偏联系数时空分布动态评价

Applications of CyTOF in Brain Immune Component Studies

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Engineering 2022年第9期16卷 187-197页

作者： Yan Wang baohui Xu Lixiang Xue Department of Neurosurgery Peking University Third HospitalBeijing 100191China Medical Research Center Peking University Third HospitalBeijing 100191China Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third HospitalBeijing 100191China Department of Vascular Surgery Stanford University School of MedicineStanfordCA 94305USA Biobank Peking University Third HospitalBeijing 100191China

The brain is the most heterogeneous and complex tissue in the body.Previous studies have shown that immune cells are essential functional components in both healthy and pathological brains.Cytometry by the time of flight(CyTOF)is a high-dimensional single-cell detection technology that allows measurements of up to 100 cell markers with a small number of samples.This technique enables the identification and characterization of various cell types at the single-cell level under steady-state and diseased brain conditions.This review outlines three major advantages of the CyTOF technique compared with the traditional flow cytometry approach.We also discuss CyTOF applications in brain immune cell component research in both healthy and pathological brains.

关键词： CyTOF Brain Immune components Neuroinflammation

Current overview on the genetic basis of key genes involved in soybean domestication

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aBIOTECH 2022年第2期3卷 126-139页

作者： Sijia Lu Chao Fang Jun Abe Fanjiang Kong baohui Liu Innovative Center of Molecular Genetics and Evolution School of Life SciencesGuangzhou UniversityGuangzhou 510006China Guangzhou Key Laboratory of Crop Gene Editing Guangzhou UniversityGuangzhou 510006China Research Faculty of Agriculture Hokkaido UniversitySapporoHokkaido 060-0808Japan

Modern crops were created through the domestication and genetic introgression of wild relatives and adaptive differentiation in new environments.Identifying the domestication-related genes and unveiling their molecular diversity provide clues for understanding how the domesticated variants were selected by ancient people,elucidating how and where these crops were domesticated.Molecular genetics and genomics have explored some domestication-related genes in soybean(Glycine max).Here,we summarize recent studies about the quantitative trait locus(QTL)and genes involved in the domestication traits,introduce the functions of these genes,clarify which alleles of domesticated genes were selected during domestication.A deeper understanding of soybean domestication could help to break the bottleneck of modern breeding by highlighting unused genetic diversity not selected in the original domestication process,as well as highlighting promising new avenues for the identification and research of important agronomic traits among different crop species.

关键词： Soybean Domestication Diversity Gene