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331.
中国石油污染管理减排探讨   总被引:1,自引:1,他引:0  
为确保实现国家"十一五"主要污染物排放总量减少10%的目标,中国石油安排了十大减排工程。工程措施是实现污染减排的主要手段,但不是唯一的措施,管理减排也是一项重要内容。文章从热力学第二定律与"麦克斯韦妖"现象出发,结合KLEM模式,分析了管理减排的理论依据,并从管理角度提出了中国石油污染减排对策建议。  相似文献   
332.
刘静玲  袁星  郎佩珍 《环境科学》1997,18(5):31-33,36
为了客观地评价2,4-二硝基甲苯与其它硝基芳烃化合物共存时对藻类的生态毒理学效应,采用OECD藻类生长抑制实验的国际标准方法,研究了2,4-二硝基甲苯与其它6种硝基芳烃化合物共存时,对斜生栅列藻的联合毒性,同时观察到细胞水平上的中毒症状,结果表明:2,4-二硝基甲苯加对硝基苯胺。2,4-二硝基甲苯加对二硝基苯;2,4-二硝基甲杠加对硝基苯甲醚均表现为协同作用。2,4-二硝基甲苯加对硝基苯酚,2,4  相似文献   
333.
Should north Australia’s extensive populations of feral animals be eradicated for conservation, or exploited as a rare opportunity for Indigenous enterprise in remote regions? We examine options for a herd of banteng, a cattle species endangered in its native Asian range but abundant in Garig Gunak Barlu National Park, an Aboriginal land managed jointly by traditional owners and a conservation agency in the Northern Territory of Australia. We reflect on the paradoxes that arise when trying to deal effectively with such complex and contested issues in natural resource management using decision-support tools (ecological-economic models), by identifying the trade-offs inherent in protecting values whilst also providing incomes for Indigenous landowners.  相似文献   
334.
工程方案选择的权重-属性决策分析方法   总被引:9,自引:0,他引:9  
程声通  高朗 《环境科学》2000,21(3):31-31-35
工程方案的选择是工程项目的战略决策问题 .从认知学原理出发 ,提出方案选择决策的 3个要素 :目标、权重和属性 .对决策目标体系的建立、权重的调查和赋值、属性的分析和规范化进行了讨论 ,提出了解决问题的思路和方法 .文中引用了一项工程方案决策实例 ,进一步说明权重 -属性分析方法的应用 .  相似文献   
335.
S. Corey 《Marine Biology》1981,62(1):65-72
The fecundity of 17 species of cumaceans belonging to 5 families from the eastern and western temperate regions of the Atlantic and the Canadian Arctic and Subarctic Oceans are discussed separately and then compared. The species range from 0.78 to 10.11 mm (mean carapace length) with fecundities ranging from 15.1 to 168.9 (mean number of eggs brood-1 female-1). Interspecific comparisons show that carapace volume versus volume of brood yields a very strong relationship (r=0.99). Therefore, it is a combination of carapace volume plus egg volume which determines the fecundity in the Cumacea. A discussion of the various life-history and reproductive strategies employed by the Cumacea is included.  相似文献   
336.
臭氧及臭氧层破坏带来的灾害与防灾对策   总被引:1,自引:0,他引:1  
郎根栋 《灾害学》1990,(2):90-94
大气中臭氧衰竭及臭氧层的破环,已引起全世界多种学科和各国政府的关注。本文引用大量资料,就臭氧的生成、性质和臭氧层遭受破坏的情况、原因、后果以及为保护臭氧层而采取的对策、措施,作了扼要的阐述,期望对了解世界灾情和开展研究工作有所借鉴。  相似文献   
337.
338.
Air pollution has been associated with an increased incidence of respiratory disease. However, significant differences may exist between air pollution levels measured at conventional fixed monitoring stations and actual levels inhaled by a subject. Furthermore, studies of effects of air pollution might best be done using asthmatics as study subjects, since they have irritable airways. This is a preliminary report of a study using a control and asthmatic group in which effects of air pollution are assessed by sympton and medication diaries and simple pulmonary function tests. Air pollution exposure is measured using a small portable sampler for particulates, SO2 and NO2; these samplers are carried by the subject (“personal”) and are situated inside and outside the home. Levels obtained are compared to data obtained from the same type of sampler located at a fixed monitoring station. Preliminary analysis of the data shows that the levels of pollutants are low and there are significant differences between the four air pollution measurements, with weak correlations among the various measurements. In this preliminary report, change in pulmonary function during the day correlates only with personal NO2 measurements. This suggests the need for estimating air pollution exposure using “personal” samplers, when investigating health effects.  相似文献   
339.
Human milk samples from women in Middle Hesse, Germany were chemically analyzed for contamination levels of alpha-, beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT as well as the PCB-congeners no. 28, 31, 49, 52, 101, 118, 138, 153, 156, 170 and 180. Changes in concentrations of these compounds in human milk over an extended time period were studied by comparing samples from 1984/85, 1990/91 and 1995. In addition, concentrations of the nitro-aromatic compounds musk xylene and musk ketone were determined in the 1995 samples. The study showed statistically highly significant (p<0.001) reductions in levels of beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT, in human milk from 1995 compared to samples from 1984/85. A weakly significant reduction (p<0.05) of alpha-HCH was also observed. For low-chlorinated PCB congeners, on the other hand, a highly significant increase of PCB no. 28 was detected and concentrations of congeners no. 31, 49 and 52 remained unchanged. Concentrations of the high-chlorinated congeners no. 101, 138, 153 and 180 dropped (highly significant). A highly significant reduction of PCB no. 118 and 156 occurred between 1990/91 and 1995, but a highly significant increase was found for no. 170. Lower levels of hydrocarbon contamination of human milk samples from 1995 than were found in samples from 1984/85 and 1990/91 can be seen to result partially from voluntary reductions, but primarily reflect restrictive environmental legislation in the Federal Republic of Germany. Mean concentrations of musk xylene and musk ketone in samples from 1995 were 41 microg/kg and 10 microg/kg milk fat, respectively.  相似文献   
340.
原子吸收分光光度法测定镉污染人群头发镉含量   总被引:4,自引:0,他引:4  
发样经硝酸消解,用火焰原子吸收分光光度法测定镉含量。探讨了9种共存元素的干扰程度,采用模拟人发元素组成的标准样制作标准曲线,以修正基体效应。  相似文献   
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