Trace metal concentration in Great Tit (Parus major) and Greenfinch (Carduelis sinica) at the Western Mountains of Beijing, China

We examined the concentrations of 11 trace metals in tissues from 10 body parts of Great Tits and Greenfinches collected at Badachu Park in the Western Mountains of Beijing, China to assess the metal accumulation level, distribution among body parts, and species and gender related variations. The highest concentrations of Hg, Ni, Zn, and Mn were found in the feather; Pb and Co in the bone; Cd, Cr, and Se in the kidney, and Cu in the liver and heart. Metal concentrations had substantial interspecific variation with Great Tits showing higher levels of Hg, Cr, Ni, and Mn than Greenfinches in tissues of most body parts. Gender related variations were body part and species specific. Meta-analyses using data from this study and other studies suggested that metal concentrations of Great Tits at our study site were relatively low and below the toxic levels.     

县(市)地震应急能力评价指标体系的构建

县(市)是我国开展地震应急工作的基础执行层面,县(市)地震应急能力的高低直接关系到我国整个地震应急工作的成败。从县(市)地震应急能力的内涵分析出发,结合通过"汶川地震灾区县(市)地震应急能力实地调研"工作取得的认识,初步构建了县(市)地震应急能力的评价指标体系。     

Arsenic in Drinking Water and Its Removal

Superfluous arsenic in drinking water can do harm to human health. In this paper, a broad overview of the available technologies for arsenic removal has been presented on the basis of literature survey. The main treatment methods included coagu- lation-sedimentation, adsorption separation and ion exchange, membrane technique, which have both advantages and disadvan- tages. It concluded that the selection of treatment process should be site specific and prevailing conditions and no process can serve the purpose under diverse conditions as each technology has its own limitations. In order to gain good results, some methods should be improved.     

一种改进的模糊聚类方法在大气环境质量评价中的应用

一般的模糊聚类分析方法只能解决大气污染状况的顺序问题,或只能得出此地与彼地的大气质量状况的相似程度,而不能同时确定大气质量的具体等级。本文提出的一种改进的模糊聚类分析方法解决了这一问题、该方法的主要改进在于:①以各污染因子的污染程度的分级标准值为聚类中心,待分样本与聚类中心之间的相似系数或待分样本隶属于某一类的隶属函数作为聚类函数;②相似系数设计为几何平均最小型,隶属函数设计为正态分布型。实例计算和比较表明,该方法是大气环境质量评价中的一种较好的方法。     

《建筑业安全卫生公约》简介

2001年10月27日,第九届全国人大常委会第24次会议审议批准了在我国执行国际劳工组织第167号公约——《建筑业安全卫生公约》。该公约是1988年6月,国际劳工局(ILO)理事会在瑞士日内瓦召开的国际劳工组织第75届大会上以第167号文公布的,并以第175号文公布了《建筑业安全卫生建议书》。《建筑业安全卫生公约》是国际劳工组织建筑业安全与卫生方面的标准,《建筑业安全卫生建议书》则是标准的条文说明。     

油田采出水处理技术探讨

对油田采出水进行处理以净化水质,达到各种目的所要求的水质标准,可采用污水回注的处理工艺,污水作为热采锅炉给水处理工艺,污水外排处理工艺。由于不同的水质要求,具体选择最佳的水处理工艺,达到净化水质保护环境的目的。     

含油污水处理技术与发展趋势

含油污水处理技术有物理处理技术,化学处理技术,物理化学处理技术以及生物技术和生化处理技术等。列出了各种技术的具体应用,指明了各种含油污水处理技术的发展趋势。     

石油烃在水面上蒸发过程的研究

原油溢流到水体后对水体造成污染。研究油污的转化规律对于污染事故评价、污染治理方面有着非常重要的意义。通过对三种不同性质的原油进行的风化和蒸发实验 ,证明三种原油低组分具有很快的蒸发速度 ,4天时间就可蒸发掉90 %以上的原油 ,同时得出了不同原油的蒸发规律。     

Cornstarch explosion experiments and modeling in vessels ranged by height/diameter ratios

Height to diameter (H/D) ratio is one of the important parameters affecting premixed particle–air combustion characteristics. This paper focuses on the behavior of cornstarch combustion in closed vessels with changed H/D ratios and fixed volumes; and a combustion model is employed to simulate the experiments. An Eulerian–Lagrangian approach for two-phase flows was used in the model and conservation equations of unsteady turbulent two-phase reacting flows were solved in two-dimensional domains. Heat loss to the vessel walls was taken into consideration in the model. The simulation results have a good agreement with those of experiments. Further simulations were carried out for higher H/D ratios from 8 to 15. These results show that H/D=8 is a changing point. When H/D<8, the maximum pressure and the rate of maximum pressure rise decrease with increasing H/D ratios. While H/D>8, the both have an increasing tendency with increasing H/D ratios.     

The Time Invariance Principle,the absence of ecological chaos,and a fundamental pitfall of discrete modeling

This paper is to show that most discrete models used for population dynamics in ecology are inherently pathological that their predications cannot be independently verified by experiments because they violate a fundamental principle of physics. The result is used to tackle an on-going controversy regarding ecological chaos. Another implication of the result is that all dynamical systems must be modeled by differential equations. As a result it suggests that researches based on discrete modeling must be closely scrutinized and the teaching of calculus and differential equations must be emphasized for students of biology.