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Size Distributions of Aerosol Sulfates and Nitrates in Beijing during the 2008 Olympic Games： Impacts of Pollution Control measures and Regional Transport

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Advances in Atmospheric Sciences 2013年第2期30卷 341-353页

作者： WANG Xinfeng WANG Tao Ravi Kant PATHAK mattias HALLQUIST GAO Xiaomeit NIE Wei XUE Likun GAO Jian GAO Rui ZHANG Qingzhu WANG Wenxing WANG Shulan CHAI fahe CHEN Yizhen Environment Research Institute Shandong University Jinan 250100 Department of Civil and Environmental Engineering Hong Kong Polytechnic University Hong Kong Chinese Research Academy of Environmental Science Beijing 100012 Department of Chemistry University of Gothenburg Gothenburg Sweden

For the 2008 Olympic Games, drastic control measures were implemented on industrial and urban emissions of sulfur dioxide （SO2）, nitrogen oxides （NOx） and other pollutants to address the issues of poor air quality in Beijing. To investigate the effects of SO2 and NOx reductions on the particulate sulfate and nitrate concentrations as well as their size distributions, size-segregated aerosol samples were collected using micro-orifice uniform deposit impactors （mOUDIs） at urban and downwind rural sites in Beijing before and after full-scale controls. During the sampling period, the mass concentrations of fine particles （PmI.s） at the urban and rural sites were 94.0 and 85.9 p.g m-3, respectively. more than 90% of the sulfates and 60% of nitrates formed as fine particles. Benefiting from the advantageous meteorological conditions and the source controls, sulfates were observed in rather low concentrations and primarily in condensation mode during the Olympics. The effects of the control measures were separately analyzed for the northerly and the southerly air-mass-dominated days to account for any bias. After the control measures were implemented, Pm, sulfates, and nitrates were significantly reduced when the northerly air masses prevailed, with a higher percentage of reduction in larger particles. The droplet mode particles, which dominated the sulfates and nitrates before the controls were implemented, were remarkably reduced in mass concentration after the control measures were implemented. Nevertheless, when the polluted southerly air masses prevailed, the local source control measures in Beijing did not effectively reduce the ambient sulfate concentration due to the enormous regional contribution from the North China Plain.

关键词： size distribution aerosol sulfate nitrate control effect Olympic Games

A large-scale outdoor atmospheric simulation smog chamber for studying atmospheric photochemical processes:Characterization and preliminary application

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Journal of Environmental Sciences 2021年第4期33卷 185-197页

作者： Junling Li Hong Li Xuezhong Wang Weigang Wang maofa Ge Hao Zhang Xin Zhang Kun Li Yan Chen Zhenhai Wu fahe Chai Fan meng Yujing mu Abdelwahid mellouki Fang Bi Yujie Zhang Lingyan Wu Yongchun Liu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Key Laboratory of Atmospheric Chemistry China Meteorological AdministrationBeijing 100081China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Laboratory of Atmospheric Chemistry Paul Scherrer Institute(PSI)5232 VilligenSwitzerland Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Institut de Combustion Aérothermique Réactivitéet EnvironnementCentre National de la Recherche Scientifique(ICARE-CNRS)Observatoire des Sciences de l’Univers en région Centre(OSUC)CS 5006045071 cedex02 OrléansFrance Beijing Advanced Innovation Center for Soft matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Understanding the formation mechanisms of secondary air pollution is very important for the formulation of air pollution control countermeasures in ***,a large-scale outdoor atmospheric simulation smog chamber was constructed at Chinese Research Academy of Environmental Sciences(the CRAES Chamber),which was designed for simulating the atmospheric photochemical processes under the conditions close to the real atmospheric *** chamber consisted of a 56-m^(3) fluorinated ethylene propylene(FEP) Teflon film reactor,an electrically-driven stainless steel alloy shield,an auxiliary system,and multiple detection *** performing a series of characterization experiments,we obtained basic parameters of the CRAES chamber,such as the mixing ability,the background reactivity,and the wall loss rates of gaseous compounds(propene,NO,NO_(2),ozone) and aerosols(ammonium sulfate).Oxidation experiments were also performed to study the formation of ozone and secondary organic aerosol(SOA),including α-pinene ozonolysis,propene and 1,3,5-trimethylbenzene *** and seed effects on the vapor wall loss and SOA yields were obtained in this work:higher temperature and the presence of seed could reduce the vapor wall loss;SOA yield was found to depend inversely on temperature,and the presence of seed could increase SOA *** seed was suggested to be used in the chamber to reduce the interaction between the gas phase and chamber *** results above showed that the CRAES chamber was reliable and could meet the demands for investigating tropospheric chemistry.

关键词： Outdoor smog chamber Characterization experiments Photo-oxidation reactions Secondary organic aerosol

青藏高原黑海盆地天然气水合物成藏要素及前景预测

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非常规油气 2024年第5期11卷 60-69页

作者：晁海德徐永锋蔡廷俊李磊赵维孝薛晟李吉庆赵洪岳王帆李青谢菁青海省第四地质勘查院西宁810000 青海省页岩气资源重点实验室西宁810000 青海省第二地质勘查院西宁810000

为了搞清青藏高原多年冻土区黑海盆地天然气水合物成藏条件及其资源前景,通过实地勘查、样品采集及测试和资料二次开发等方式,开展了物源探究、地温统计、水源追索、冻土和储集运移条件的调查等工作。研究结果表明:1)物源充足,希里可特... 详细信息

为了搞清青藏高原多年冻土区黑海盆地天然气水合物成藏条件及其资源前景,通过实地勘查、样品采集及测试和资料二次开发等方式,开展了物源探究、地温统计、水源追索、冻土和储集运移条件的调查等工作。研究结果表明:1)物源充足,希里可特组烃源岩具有较高的有机质丰度和成熟度,Ⅲ型有机质类型是主要物源,八宝山组烃源岩提供次要物源;2)地温适宜,平均温度为-5~1℃;3)地下水水源较充足,补给源主要是大气水和冰雪融水;4)冻土发育,冻土厚度为10~250 m;5)储集运移条件良好,希里可特组、八宝山组和第四系中的砂岩层,各岩层中发育的裂缝、孔隙以及次级高角度断裂是天然气水合物储集、运移的空间和通道;6)天然气水合物成藏前景较好,在黑海盆地优选出成藏远景区1处。以上成果认识,对整个东昆仑乃至青藏高原地区天然气水合物远景区预测具有指导意义。

关键词：黑海盆地天然气水合物成藏要素资源前景

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北京市秋季大气边界层结构与特征分析

北京大学学报（自然科学版） 2006年第2期42卷 220-225页

作者：张鑫蔡旭晖柴发合北京大学环境科学系北京100871 中国环境科学研究院北京100012

利用2000年9～10月北京市西部城、郊3个站点的探空资料，分析该地区秋季边界层高度的平均变化规律，探讨边界层内温度、风向、风速的廓线性质和结构特征，了解其时空变化和差异。结果表明，北京市秋季白天边界层最大高度平均约1km，夜... 详细信息

利用2000年9～10月北京市西部城、郊3个站点的探空资料，分析该地区秋季边界层高度的平均变化规律，探讨边界层内温度、风向、风速的廓线性质和结构特征，了解其时空变化和差异。结果表明，北京市秋季白天边界层最大高度平均约1km，夜间稳定层高度在200～400m之间。晴朗天气里，白天城区边界层温度高于郊区，反映出城市热岛的作用，夜间热岛现象不明显。较低的边界层高度和其顶部经常维持的强稳定层（强逆位温层）阻断上下层流动的关联，有利于近地面大气维持静稳状态和该季节雾、氟天气的出现。夜问约400m以下气层的流动大体分为3种形态，即整层小风型、低空急流型和贴地风速极大型。温度层结与夜间流动结构有密切对应关系。

关键词：大气边界层风-温结构北京秋季

A nomogram for individualized estimation of survival among adult patients with adrenocortical carcinoma after surgery:a retrospective analysis and multicenter validation study

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Cancer Communications 2019年第1期39卷 683-695页

作者： Jianqiu Kong Junjiong Zheng Jinhua Cai Shaoxu Wu Xiayao Diao Weibin Xie Xiong Chen Chenyi Liao Hao Yu Xinxiang Fan Chaowen Huang Zhuowei Liu Wei Chen Qiang Lv haide.Qin Jian Huang Tianxin Lin Department of Urology Sun Yat-Sen Memorial HospitalSun Yat-Sen University107 Yan Jiang West RoadGuangzhou 510120GuangdongP.R.China Guangdong Provincial Key Laboratory of malignant Tumor Epigenetics and Gene Regulation Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120GuangdongP.R.China Department of Neurology Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120GuangdongP.R.China Department of Obstetrics and Gynecology Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630GuangdongP.R.China Department of Urology Sun Yat-sen University Cancer CenterGuangzhou 510060GuangdongP.R.China Department of Urology First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080GuangdongP.R.China Department of Urology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029JiangsuP.R.China State Key Laboratory of Oncology in South China Guangzhou 510120GuangdongP.R.China

Background:Clinical outcome of adrenocortical carcinoma(ACC)varies because of its heterogeneous nature and reliable prognostic prediction model for adult ACC patients is *** objective of this study was to develop and externally validate a nomogram for overall survival(OS)prediction in adult patients with ACC after ***:Based on the data from the Surveillance Epidemiology,and End Results(SEER)database,adults patients diagnosed with ACC between January 1988 and December 2015 were identified and classified into a training set,comprised of 404 patients diagnosed between January 2007 and December 2015,and an internal validation set,com-prised of 318 patients diagnosed between January 1988 and December *** endpoint of this study was *** nomogram was developed using a multivariate Cox proportional hazards regression algorithm in the training set and its performance was evaluated in terms of its discriminative ability,calibration,and clinical *** nomogram was then validated using the internal SEER validation,also externally validated using the Cancer Genome Atlas set(TCGA,82 patients diagnosed between 1998 and 2012)and a Chinese multicenter cohort dataset(82 patients diag-nosed between December 2002 and may 2018),***:Age at diagnosis,T stage,N stage,and m stage were identified as independent predictors for OS.A nomo-gram incorporating these four predictors was constructed using the training set and demonstrated good calibration and discrimination(C-index 95%confidence interval[CI],0.715[0.679-0.751]),which was validated in the internal validation set(C-index[95%CI],0.672[0.637-0.707]),the TCGA set(C-index[95%CI],0.810[0.732-0.888])and the Chi-nese multicenter set(C-index[95%CI],0.726[0.633-0.819]),***,the nomogram was able to successfully distinguished patients with a high-risk of mortality in all enrolled patients and in the subgroup *** curve analysis indicated that the nomogram wa

关键词： Adrenocortical carcinoma Adult patients Overall survival Nomogram Validation Decision curve analysis Surveillance Epidemiology and End Results(SEER) The Cancer Genome Atlas(TCGA) multicenter

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中低档乌龙茶中茶多糖提取工艺优化

农业工程学报 2006年第12期22卷 245-247页

作者：陈发河吴光斌田标陈铮集美大学生物工程学院厦门361021

该文以中、低档乌龙茶为原料,通过正交试验,研究了浸提温度、浸提时间、料水比和乙醇浓度4个因素对茶多糖得率的影响,并探讨茶多糖中蛋白质的脱除技术。研究结果表明:浸提温度对茶多糖得率的影响程度达到极显著水平,浸提时间、料水比和... 详细信息

该文以中、低档乌龙茶为原料,通过正交试验,研究了浸提温度、浸提时间、料水比和乙醇浓度4个因素对茶多糖得率的影响,并探讨茶多糖中蛋白质的脱除技术。研究结果表明:浸提温度对茶多糖得率的影响程度达到极显著水平,浸提时间、料水比和沉淀的乙醇浓度对茶多糖得率没有显著影响。乌龙茶茶多糖提取的最佳工艺条件为:浸提温度90℃,浸提时间80 m in,料水比1∶25,沉淀剂乙醇浓度60%,乌龙茶茶多糖得率为10.15%,含量88.04%。以3次脱蛋白处理为宜,茶多糖中蛋白质脱除率为64.22%。另外,经红外光谱和紫外光谱分析,乌龙茶茶多糖主要是吡喃多糖,并且有蛋白质特征吸收峰。

关键词：乌龙茶多糖提取脱除蛋白

PmP柱前衍生化HPLC法测定黄秋葵多糖的单糖组成

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食品科学 2019年第4期40卷 266-271页

作者：周彦强吴光斌陈发河集美大学食品与生物工程学院福建厦门361000

采用1-苯基-3-甲基-5-吡唑啉酮为柱前衍生化试剂,结合反相高效液相色谱法,建立同时测定黄秋葵多糖中8种单糖组分的方法。采用InfinityLab Poroahell C18色谱柱为固定相,流动相为磷酸盐缓冲液(0.1 mol/L,pH 6.85)-乙腈(82∶18,V/V),流速... 详细信息

采用1-苯基-3-甲基-5-吡唑啉酮为柱前衍生化试剂,结合反相高效液相色谱法,建立同时测定黄秋葵多糖中8种单糖组分的方法。采用InfinityLab Poroahell C18色谱柱为固定相,流动相为磷酸盐缓冲液(0.1 mol/L,pH 6.85)-乙腈(82∶18,V/V),流速为1.0 mL/min,柱温25℃,紫外检测器,波长250 nm。各单糖组分的线性范围较宽,相关系数均大于0.999,检出限为0.13～0.45 mg/kg,定量限为0.43～1.49 mg/kg,相对标准偏差小于5%,加标回收率为94.51%～106.44%。方法灵敏度高、准确性好、实用可靠,适用于黄秋葵多糖的单糖组分分析。同时测定从黄秋葵中顺序提取的热水浸提物(hot buffer soluble solution,HBSS)、螯合剂浸提物(chelating agent solublesolution,CHSS)和碱提物(dilute alkaline soluble solution,DASS)的单糖组成,确定其单糖组分的物质的量比。HBSS中,甘露糖∶鼠李糖∶葡萄糖醛酸∶半乳糖醛酸∶葡萄糖∶半乳糖∶阿拉伯糖=0.1∶7.0∶0.4∶5.8∶0.9∶14.6∶1.5;CHSS中,鼠李糖∶半乳糖醛酸∶半乳糖∶阿拉伯糖=4.7∶61.8∶9.6∶5.3;DASS中,甘露糖∶鼠李糖∶半乳糖醛酸∶葡萄糖∶半乳糖∶阿拉伯糖=9.5∶5.4∶1.3∶10.8∶2.4∶7.6。

关键词：黄秋葵单糖组分 1-苯基-3-甲基-5-吡唑啉酮柱前衍生高效液相色谱

microstructure and Properties Characterization of WC-Co-Cr Thermal Spray Coatings

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Journal of minerals and materials Characterization and Engineering 2018年第4期6卷 482-497页

作者： Karla Ofelia méndez-medrano Cecilio Jesús martínez-González Francisco Alvarado-Hernández Omar Jiménez Víctor Hugo Baltazar-Hernández haide. Ruiz-Luna Unidad Académica de Ingeniería Universidad Autónoma de Zacatecas Zacatecas México CUCEI Universidad de Guadalajara Jalisco México Unidad Académica de Ingeniería CONACYT-Universidad Autónoma de Zacatecas Zacatecas México

WC-Co-Cr coatings are widely employed due to their improved wear resistance and mechanical properties, however, the properties and performance of these coatings are compromised by the processing parameters of each spraying technique. Therefore, this study is aimed to evaluate and determine the effect of the deposition parameters on the properties and microstructural characteristics of WC-Co-Cr coatings using a more economical thermal spray technique. In particular, the influence of flame spray parameters on the microstructure, crystal structure, hardness, and sliding wear resistance of WC- Co-Cr coatings was examined. Two parameters were considered: Type of flame (reducing, neutral and oxidizing), and the spray torch nozzle exit area. Results indicated that WC particles undergo considerable degree of decarburization and dissolution during spraying, showing substantial amounts of W2C, W, and Co3W3C, for all the considered conditions. However, the extent of phase transformation depended largely on the flame chemistry. The microstructure of the coatings was mainly affected by the spray nozzle. Regarding the sliding wear behavior, the coatings with uniform distribution of hard particles provided the best wear resistance. The decomposition of WC into W2C phase seems to have meaningless significance in the mass loss, nevertheless, the WC phase transformation to metallic tungsten and η-phase (Co3W3C) produce higher wear rates due to deficiency of carbide particles and embrittlement of the binder phase which induces cracking and delamination of the splats.

关键词： WC-Co-Cr Thermal Spray Coating X-Ray Phase Content microstructure Flame

HPLC法同时测定采后莲雾果实7种有机酸的含量

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食品科学 2021年第4期42卷 175-180页

作者：段云飞吴光斌叶洪陈昭华张珅陈发河集美大学食品与生物工程学院福建厦门361000 宁德海关技术中心福建宁德352100

为探讨采后莲雾果实有机酸代谢对果实絮状绵软和品质的影响,建立同时测定莲雾果实中7种有机酸含量的高效液相色谱法。采用Atlanis T3色谱柱(4.6 mm×250 mm,5μm)分离并进行梯度洗脱,流动相为甲醇和0.02 mol/L的磷酸盐(pH 2.2),流速0.5 ... 详细信息

为探讨采后莲雾果实有机酸代谢对果实絮状绵软和品质的影响,建立同时测定莲雾果实中7种有机酸含量的高效液相色谱法。采用Atlanis T3色谱柱(4.6 mm×250 mm,5μm)分离并进行梯度洗脱,流动相为甲醇和0.02 mol/L的磷酸盐(pH 2.2),流速0.5 mL/min,柱温25℃,紫外检测器,检测波长213 nm。在此色谱条件下,各有机酸组分都很好地分离,线性范围较宽,相关系数不低于0.9995,检出限为0.001~0.014 mg/g,定量限为0.003~0.042 mg/g,加标回收率为86.84%~98.86%,相对标准偏差小于5%。该方法高效快捷、定量准确、灵敏度高,适用于莲雾果实7种有机酸含量的同时测定。测得莲雾果实贮藏期间7种有机酸含量变化分别为丙酮酸0.395~0.975 mg/g、苹果酸6.951~10.059 mg/g、抗坏血酸0.013~0.172 mg/g、乳酸0.030~0.735 mg/g、乙酸0.263~0.702 mg/g、柠檬酸1.658~5.370 mg/g、富马酸0.269~0.518 mg/g。

关键词：高效液相色谱莲雾有机酸