Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China

Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons,and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25 th to 27 th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th–8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene(T/B) during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was5.8 ppb/ppb, significantly higher than the values of 0.2–1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better.     

纳米银材料的生物安全性研究进展

纳米银材料被广泛应用到医疗、化工、生物等许多领域,增加了与人类接触的可能性,因此关注其生物安全性是很有必要的。本文对近年来纳米银的抗菌性和生物安全性研究进行了综述。首先分析了纳米银的皮肤毒性、呼吸系统毒性、消化系统毒性和其他组织毒性,其次分析了体外细胞毒性和细胞内纳米银与生物大分子相互作用,最后对纳米银材料的人群暴露生物安全性及纳米银与银离子毒性关系进行了探讨。本文旨在为纳米银的毒性作用机制研究提供参考,为建立标准的纳米银安全性评价体系提供依据。     

试论矿山环评中的生态恢复评价问题

矿山生态恢复是矿山环保对策中的一项技术较强的措施之一，它既有防治水土流失的功能，又有降解有毒污染的功能，并能产生较好的经济效益。但没有科学依据而盲目进行生态恢复，就有可能对环境和人类带来风险，为减少风险，在矿山开发前的环境影响评价中，就应对生态恢复这一措施进行评价，提出合理的恢复模式，为决策部门提供科学依据。     

多沙大河的扩散示踪研究

污染物在水体中的扩散规律研究已引起越来越多人的关注。通过现场扩散示踪实验求得扩散系数，进而对污染物的扩散规律予以定量描述，是一种可靠易行的方法。对黄河托克托至河曲段的实际研究表明，以Ｃｒ２Ｏ或Ｆ－为示踪剂，运用Ｔａｙｌｏｒ模型进行多沙大河的污染物扩散规律研究可以取得满意的结果。同时，利用现场示踪实验结果与经验公式的结合可以预测不同情况下的纵向扩散系数，从而得出污染物的允许排放量，这将有利于污染物在水体中行为的深入研究。     

县域土地利用细碎度综合度量与空间分异研究——以江苏省东海县为例

土地细碎化是与土地规模经营理念相背离的一种土地形态,细碎化的土地经营模式会造成土地利用效率下降、粮食减产以及景观美观度降低等一系列问题。目前,土地细碎化程度的衡量多通过细碎度表征,但尚无统一标准,且主要针对农用地。以江苏东海县为例,首先结合景观指数与主成分分析,分别计算耕地、基础设施用地、居民点用地以及生态用地的细碎度,再通过系统聚类,分析不同地类细碎度组合的地域分异特征。结果显示：不同用地类型的细碎度是自然、社会经济的综合影响结果,耕地细碎度与居民点细碎度有着较显著的正相关关系,与生态用地细碎度有着较显著的负相关关系,基础设施用地细碎度和居民点细碎度存在一定的正相关关系,与生态用地细碎度存在一定的负相关关系,土地细碎度基于不同自然、社会经济条件,其分区也有着特定的区位特征。探讨不同用地类型细碎度间的关联性及空间分异特征可以为土地利用、经济发展以及景观改善等提供科学的引导     

Beijing Ministerial Declaration on Environment and Development

Abstract

As the main organic pollutant in municipal living waste, kitchen waste causes secondary pollution in the course of its being gathered and transported to the landfill by mixing with other refuse and by decomposition. This makes pollution prevention more difficult and raises the cost of landfill engineering. However, the amount of solid waste to be treated can be decreased and such pollution burden lessened by disposing of the solid waste in local municipal areas. The program in Beijing also shows that this works well with our situation in China and can accelerate marketization and public participation.     

人工神经网络模型在地震安全评价中的应用

地震影响系数是地震安全评价的一个重要参数 ,其分布受到场地条件和基岩条件的共同影响 ,对场地影响的考虑相对比较成熟 ,对基岩的影响则相对考虑较少 ,难以满足城市和重大工程设防的要求。综合考虑基岩条件和场地条件的地震影响系数计算 ,关键在于确定基岩裂缝、能量、位移、场地等指标的分布与地震影响系数之间的关系 ,由于这种非线性关系需要构建多元非线性模型 ,故通过应用人工神经网络方法 ,得到地震影响系数计算模型。以唐山市为实例 ,进行了计算并分析了计算结果 ,为城市规划和工程建设提出了几点建议     

Development and validation of an enzyme-linked immunosorbent assay for vitellogenin in Chinese loach (Misgurnus angaillicaudatus)

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of vitellogenin (Vtg) in the plasma of Chinese loach (Misgurnus angaillicaudatus). Vtg was isolated by anion exchange membrane chromatography from the plasma of 17beta-estradiol (E(2))-treated loach. Polyclonal antibody against Vtg was raised in rabbits, and the specificity of the antibody was assessed by Western blotting analysis. No cross-reactivity was observed with plasma from male loach. Plasma samples from vitellogenic females and E(2)-treated males were diluted parallel with the purified Vtg standard curve in the ELISA. The detection limit of the assay was 5.7 ng ml(-) (1) and a working range of the standard curve was between 15.6 and 1000 ng ml(-) (1). The intra- and inter-assay coefficients of variations were 6.9% and 10.4%, respectively. The recovery was 104.4%. The assay was applied for measuring vitellogenin concentration in the plasma from 24 wild Chinese loach from Lianyungang, Jiangsu Province, in October 2003. It was found that, in addition to females (plasma Vtg concentration ranging from 518.4 microg ml(-) (1) to 1922.3 microg ml(-) (1)), male loach showed low plasma Vtg--from undetectable (two fish) to 2.9+/-0.7 microg ml(-) (1) (mean+/-S.D.). The results indicate that this method provides a valuable tool for the study of estrogenic effect in Chinese loach.     

原油及产品对藻类毒性影响研究

藻类具有种类繁多，个体小，生长繁殖迅速，对毒物的毒性敏感等特点，它长时间在水中生长，能客观地反映原油及产品对水体污染所产生的毒害综合效应。实验室中毒性研究通常采用纯种藻类培养来评价油的急性和早期毒性影响。经过实验室研究及原油泄漏现场调查研究表明：在含油的生态系统中油能刺激藻类的生长。在油污染过的水体中，原油中的轻烃和较易挥发的组分对藻类的毒性影响最大，原油泄漏的短期毒性影响和二次影响同等重要，油对藻类种群结构也具有重要的毒性影响。