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

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 Beijing-Tianjin-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.     

黄浦江铅的人体健康水质基准研究

铅是我国水环境质量监控的重点污染物之一.我国成人和儿童铅中毒事件时有发生,制定铅的人体健康水质基准在我国有着特殊意义.本文以黄浦江流域为研究对象,采集并分析流域水样和不同营养级的鱼样本中铅含量,结合文献调研,确定了人体暴露参数、生物蓄积系数等相关本土参数,推导出该流域铅的基于人体健康风险水质基准值为13.45μg·L~(-1).虽然该值略高于我国和大部分发达国家的现行饮用水标准(10μg·L~(-1)),但明显低于我国地表三类水环境标准(50μg·L~(-1)),提示黄浦江流域水体铅污染需要进一步加强防控.另外,通过引入铅的敏感人群儿童对基准推导进行了优化,并应用IEUBK模型(The Integrated Exposure Uptake Biokinetic Model,综合暴露吸收生物动力学模型)对儿童血铅含量进行预测分析.研究发现引入了铅的敏感人群儿童后,推导得出基于人体健康的水质基准值为1.718μg·L~(-1),提示黄浦江流域的儿童在日常饮用水的选择上,应选择铅浓度比饮水标准更低的饮用水.本研究提出本土铅的基于人体健康风险水质基准值,对我国基准技术指南案例研究以及铅相关水质标准修订等具有重要的科学意义和参考价值.     

多元热流体项目风险评价技术的应用

多元热流体技术项目近年来在新疆油田开展了众多现场试验工作,取得了一定进展。项目现场装置区主要包括复合热载体发生器及其配套系统,项目实施过程危险有害因素较多。通过研究分析,对生产单元进行了划分,辨识了各单元危险有害因素,运用HSE风险评价工具对风险进行了评价,提出了对策措施。     

中国CDM项目开发现状及存在问题分析研究

清洁发展机制(CDM)是国际社会实现温室气体减排的履约机制之一。目前中国已成为CDM市场的主要输出国,但在CDM项目开发过程中还存在很多问题,例如区域分布不平衡、碳排放权交易标准不统一、缺乏激励机制等。在经济发展和节能减排的双重压力下,中国政府声明将严格遵守《巴黎协定》,正在积极落实已提出的到2020年控制温室气体排放行动目标,并向联合国提交了到2030年的"国家自主贡献"行动目标。中国的积极行动推动了全球气候问题的解决。     

Fluorescence regional integration and differential fluorescence spectroscopy for analysis of structural characteristics and proton binding properties of fulvic acid sub-fractions

Structural characteristics and proton binding properties of sub-fractions (FA3–FA13) of fulvic acid (FA), eluted stepwise by pyrophosphate buffer were examined by use of fluorescence titration combined with fluorescence regional integration (FRI) and differential fluorescence spectroscopy (DFS). Humic-like (H-L) and fulvic-like (F-L) materials, which accounted for more than 80% of fluorescence response, were dominant in five sub-fractions of FA. Based on FRI analysis, except the response of F-L materials in FA9 and FA13, maximum changes in percent fluorescence response were less than 10% as pH was increased from 2.5 to 11.5. Contents of carboxylic and phenolic groups were compared for fluorescence peaks of FA sub-fractions based on pH-dependent fluorescence derived from DFS. Static quenching was the dominant mechanism for binding of protons by FA sub-fractions. Dissociation constants (pKa) were calculated by use of results of DFS and the modified Stern-Volmer relationship. The pKa of H-L, F-L, tryptophan-like and tyrosine-like materials of FA sub-fractions exhibited ranges of 3.17–4.06, 3.12–3.97, 4.14–4.45 and 4.25–4.76, respectively, for acidic pHs. At basic pHs, values of pKa for corresponding materials were in ranges of 9.71–10.24, 9.62–10.99, 9.67–10.31 and 9.33–10.28, respectively. At acidic pH, protein-like (P-L) materials had greater affinities for protons than did either H-L or F-L materials. The di-carboxylic and phenolic groups were likely predominant sites of protonation for both H-L and F-L materials at both acidic and basic pHs. Amino acid groups were significant factors during proton binding to protein-like materials of FA sub-fractions at basic pH.     

云南边疆环境问题初探

云南边疆风景秀丽,资源富饶,但由于各种因素,云南边疆的环境受到了严重破坏。本文通过列举事实,对云南边疆环境破坏的现状与程度进行了详细阐述,并结合实例直言不讳地分析了边疆环境破坏的原因,尝试性地提出了保护云南边疆环境,实现边疆经济可持续发展的可行性建议。     

1951-2008年东北地区水分盈亏量时空格局

基于1951-2008年东北地区106个气象站点的实测数据,利用Penman-Monteith公式计算潜在蒸散量,并将气候水分盈亏量表示为同期降水量与潜在蒸散量之差。最后,通过Kendall秩次相关趋势分析、Morlet小波函数、Mann-Kendall突变检验等方法探讨了东北地区水分盈亏量的时空变化特征。结果表明:①1951-2008年,东北地区多年平均水分盈亏量在-850~650 mm之间变化,呈自东向西、自北向南、自东北向西南逐渐减少的空间变化趋势;②东北地区106个气象站点中有97个站点的水分盈亏量呈下降趋势,其中28个站点的下降趋势能通过P<0.05的显著性检验;③全区平均、海拉尔、长春、宽甸年际波动明显,多年平均值依次为-283.60、-427.25、-362.58、334.91 mm,四者的水分盈亏量年内分配不均匀,最小值出现在5月,最大值出现在7-8月;④水分盈亏量存在周期结构性,偏高期、偏低期交替出现,全区平均、海拉尔、长春、宽甸的第一主周期依次为26、28、25、9 a,水分盈亏量还具有突变特征,全区平均在1999年发生了一次减少突变,长春在1958、1998年各发生了一次减少突变。     

包头市空气污染与气象因素相关性研究

本文以包头市市区2007年和2008年的空气环境质量逐时监测数据和相应的地面逐时气象数据为基础,结合MM5中尺度气象模型拟合的高空气象数据,采用Pearson相关分析法,对空气环境中主要污染物二氧化硫、可吸入颗粒物的浓度与风速、近地面气温、降水、气压、相对湿度等气象因素的相关性进行了分析,探讨了逆温、静风等主要气象条件对空气环境中污染物浓度变化的影响,为改善城市空气环境质量提供技术支撑。     

关于鄂尔多斯市东胜区环境噪声功能区的划分及思考

城市区域声环境噪声功能区的划分,是城市各类噪声监测和环境管理的重要依据,也是评价一个城市声环境质量的重要依据。以城市规划为指导,按区域规划用地的主导功能确定,本文对鄂尔多斯市建城区功能区划分过程中所涉及的一些问题及功能区划分后对今后管理所起的作用等问题进行了探讨。     

包头市能源消费结构与能效分析

结合2001年~2007年统计数据,从能源消费量、能源种类、重点行业企业能源消费、能源消费结构等方面分析了包头市能源消费现状,并就单位GDP能耗、单位工业增加值能耗等能效指标,与同期全国部分省市及全区各盟市指标进行了对比分析,为包头市优化能源结构、改善环境质量、走新型工业化道路提供参考。