城市小区气象条件与污染扩散精细预报研究

从城市小区气象条件与污染扩散精细预报的科研需求和城市大气环境应急响应的应用需求出发,利用新一代全球/区域同化预报系统、城市小区尺度气象和污染扩散模式以及城市尺度污染扩散模式,对城市小区气象条件与污染扩散进行了精细预报试验,并进一步研究了城市小区尺度气象和污染扩散的精细模拟对城市尺度污染扩散模拟的影响.初步建立了城市小区气象条件与污染扩散精细预报方法,即:气象部分由全球到小区逐级单向嵌套、污染部分由小区到城市逐级单向嵌套的方法.预报试验结果表明,这种方法是合理可行的.小区尺度精细模拟对城市尺度污染扩散模拟的影响较大,但其模拟效果还有待利用观测资料进一步验证.     

Atmospheric aerosol growth rates at different background station types

Environmental Science and Pollution Research - Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013–2017) at four background stations in the...     

Green synthesis,characterization, application and functionality of nitrogen-doped MgO/graphene nanocomposite

Environmental Science and Pollution Research - A facile, feasible, and green synthesis via an electrochemical exfoliation process was applied to synthesize nitrogen-doped MgO/graphene nanocomposite...     

Process modeling of chemical looping combustion (CLC) of municipal solid waste

Journal of Material Cycles and Waste Management - Chemical Looping Combustion (CLC) of MSW could serve as a potential treatment method for the disposal of MSW and the recovery of energy because it...     

N-nitrosodimethylamine: a disinfectant byproduct and its occurrence in wastewater.

This paper will provide wastewater treatment utility professionals with a comprehensive synthesis of information pertinent to N-nitrosodimethylamine (NDMA) so that plant operators can make informed and cost-effective decisions regarding appropriate management techniques. A suspect disinfection byproduct, NDMA is a potential carcinogen and is presently under scrutiny from the U.S. Environmental Protection Agency because it poses a threat to groundwaters from reclaimed wastewaters. Recognizing that the current state of knowledge pertaining to the occurrence and treatment of NDMA from wastewater treatment is in its infancy, the information presented in this paper is timely and will help utility professionals develop confidence toward controlling NDMA during wastewater treatment. Given the increased probability of the formation of NDMA using current wastewater treatment technologies and also in the complex matrices of the wastewaters subjected to UV treatment, the investigation of occurrence pathways and means of suppression of NDMA formation before and after treatment needs to be investigated. This paper also summarizes strategies to minimize exposure such as modifying treatment or instituting waste and agricultural management practices that minimize inorganic and organic nitrogen discharges to wastewaters.     

EXPERIMENTAL EVALUATION OF MULTIPLE CRITERIA DECISION MODELS FOR APPLICATION TO WATER RESOURCES PLANNING1

ABSTRACT: A research project was undertaken for the U.S. Army Corps of Engineers to determine the relative utility and effectiveness of four well-known multicriteria decision making (MCDM) models for applications in realistic water resources planning settings. A series of experiments was devised to examine the impact of rating and ranking procedures on the decision making behavior of users (e.g., planners, managers, analysts, etc.) when faced with situations involving multiple evaluation criteria and numerous alternative planning projects. The four MCDM models tested were MATS-PC, EXPERT CHOICE, ARIADNE, and ELECTRE. Two groups of analysts and decision makers were tested. One group consisted of experienced U.S. Army Corps planners, while the other was comprised of graduate students. Based on a series of nonparametric statistical tests, the results identified EXPERT CHOICE as the preferred MCDM model by both groups based largely on ease of use and understandability. ARIADNE fostered the largest degree of agreement within and among the two groups of individuals tested. The tests also lend support to the claim that rankings are not affected significantly by the choice of decision maker (i.e., who uses any of these MCDM models) or which of these four models is used.     

Effect of ammonia on the survival of Zacco platypus (Temminck and Schlegel) at each developmental stage

The survival rates were studied of fertilized eggs, larvae, fry, and adults of pale chub Zacco platypus (Temminck and Schlegel) exposed to various concentrations of ammonia. There was a decrease in hatching rate and an increase in deformed alevins at a concentration of 0.9 mg liter(-1) of ammonia. All alevins were deformed at a concentration of 1.6 mg liter(-1) of ammonia and no eggs hatched at a concentration of 3.1 mg liter(-1) of ammonia. No larvae survived for 84, 24 and 12 h at concentrations of 1.2, 2.0 and 4.7 mg liter(-1) of ammonia, respectively. Eighty percent of the fry died after 168 h and no fry survived for 24 h at concentrations of 1.6 and 2.1 mg liter(-1) of ammonia, respectively. Eighty percent of the adults died after 24 h and no adult survived for 12 h at concentrations of 1.0 and 1.9 mg liter(-1), respectively. Larger adults were the most susceptible to ammonia. The order of resistance to ammonia was eggs, fry, larvae, and adults.     

百重7井区钻井液对地下水的污染特性研究

百重7井区有丰富的地下水资源，为了考察钻井过程中钻井液对地下水的污染程度，我们对钻井液对地下水的污染特性进行了研究。研究结果表明，在钻井过程中由于进入地下水水层中的污染物总量很小，同时由于所使用的钻井液添加剂的可生化性较好和生物毒性小，进入地下水水层的污染物不会对水源构成严重危害。另外由于地层有一定的自我净化能力，地下水水质不会因钻井而出现较大的变化。