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601.
The renovated water in the rapid infiltration system (RI) as area for fish and duck farming is feasible. The flesh of fish and duck is edible. The farming of fish for 5 months and duck for 120 - 130 days can be accepted. It is beneficial to environment and economy, especially in developing countries. The production of fish and duck can make up for the cost of wastewater treatment.  相似文献   
602.
ThecharactersfortheboundarylayerandmechanismofacidrainformationintheQingdaoarea,ChinaLiuBaozhang,LiJinlongenterofEnvironmenta...  相似文献   
603.
Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the soil mainly retained those in the parent materials (loess). It has been found that fractional deposition among grain sizes in the process of loess transportation as well as the bioclimate in which the soil developed are main factors affecting the regional variations of elemental distribution in soil on the plateau. Contour maps of element concentrations plotted from the trend analyses exhibit the major patterns of the distributions and variations on the plateau. Furthermore, the study also provides evidence for the aeolian theory of the loess transportation in China.  相似文献   
604.
Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over Beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2, and CCl_2=CCl_2 were measured and their concentrations are 109±8, 234±13, 47±22, 97±24, 88±29, 11±1 and 17±3 (pptv), respectively.  相似文献   
605.
This paper deals briefly with the pollution caused by hazardous wastes in China, the hazardous waste management at present and the strategy that should be taken for hazardous waste management in the future. Hazardous waste problem has become one of the important environmental concerns in China. Hazardous waste have resulted in ecological and environmental destruction, caused damage to human health, and restricted economic development. Although a great effort has been devoted to the management of hazardous wastes, there remain many issues in legislation, experience, technology and finance to be solved. Some recommendations are made on the strategic measures for improving the hazardous waste management in China, particularly relating to legislation, technical development and international cooperation.  相似文献   
606.
Traffic emission and its impact on air quality in Guangzhou area   总被引:1,自引:0,他引:1  
1 IntroductionIntheprocessofrapidurbanization,totalamountofvehicleinChinaincreaseddramaticallyandreachedmorethan20millionin1995withanaverageincreaserateof15%.Becauseofpoorqualityofvehicle,badroadcondition,lowdrivingspeed,andnocatalyticconverter,theem…  相似文献   
607.
辽东湾东部砂岸严重蚀退及其原因分析   总被引:1,自引:0,他引:1  
辽东湾东部砂岸属冰后期淤长岸。近些年来遭到强烈侵蚀。不仅岬角、平直砂岸在蚀退.连一向稳定的湾内淤长岸也在转侵后退。目前,调查区100km海岸约有2/3的岸段出现严重蚀退现象,不少岸段年蚀退率已超过6m.有的沿海公路多次内迁,引起沙滩粗化、泻湖水量加大、海水倒灌、土地咸化等一系列严重灾害。  相似文献   
608.
The relation between EH [Se(VI)/Se(IV)] and pH of soil aqueous extract in Kaschin-Beck disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the system were studied. The results indicated that both humic acid and Fe2+ could enhance the reducibility of Se(VI) and MnO2, a limited oxidizability for Se(IV). Fe2+ showed a weak reducibility only at low pH value. The reducibilities of three sulfur-containing compounds for Se(VI) were in following order:thioglycollic acid > L-cysteine > sulfide  相似文献   
609.
The role of atmospheric aerosol composition in climate change   总被引:1,自引:0,他引:1  
The chemical composition of atmospheric aerosols has been investigated. Contributions ofsulfate and soot in aerosols to the atmospheric extinction are studied. Discussions are made on the problems of aerosol emitted from volcano, forest fires in northern China, 1987 and oil field fires in Kuwait, 1991. It is indicated that the changes in concentration, particle size, and chemical composition of aerosol after those events could have impacts on the climate change either regionally or globally and that the impact of aerosol particles on climate change could compensate for some temperature increase caused by greenhouse gases and the increase of surface intensity of ultraviolet radiation due to ozone layer depletion.  相似文献   
610.
EfectsofmainrangeandstrengthfactorsonchangeofCODinashalowlakeFanChengxinNanjingInstituteofGeographyandLimnology,ChineseAcad...  相似文献   
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