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971.
采用烟道气─生物法处理苎麻脱胶废水,经两年多实践表明,在操作条件下,处理后的废水中COD浓度低于国家规定的排放标准,运行费用0.0886元/m3废水。具有投资省,运行费用低,管理方便等特点。  相似文献   
972.
加压接触氧化法处理啤酒废水技术   总被引:4,自引:0,他引:4       下载免费PDF全文
介绍了加压接触氧化法处理啤酒废水的技术,当进水COD在1600mg/L左右,停留时间在6~7h时,COD去除率达90%以上。   相似文献   
973.
含油污水中胶质和沥青质含量的紫外测定方法   总被引:1,自引:0,他引:1  
探讨用紫外分光光度计快速测定经Al2O3吸附色谱柱分离后的含油污水中胶质?沥青质含量的方法,并且用国内外分析原油及渣油时所通用的四组分分析方法做对比实验,二者相对误差一般小于±5%?实验表明不同油田含油污水中胶质?沥青质含量不同,在污水处理剂的研制及筛选中,应考虑油的组成的影响   相似文献   
974.
危险废物集中焚烧处置是我国危险废物处置的最主要和最直接的方式之一。本文结合我国目前危险废物集中焚烧处置设施建设和设计现状 ,以及我国危险废物处置设施建设规划 ,在对危险废物集中焚烧处置设施设计所涉及的关键技术环节进行分析的基础上 ,提出了相应的设计技术要求  相似文献   
975.
王浩东  李仪 《环境保护科学》2004,30(4):59-60,63
分析了废物处理企业的产品及顾客分类 ,并重点讨论了废物产生单位和环境的顾客需求  相似文献   
976.
As one of the countries with large amounts of dioxin releases, the control of dioxins is a major challenge for China. Municipal solid waste (MSW) incineration should be considered a high priority source of dioxin emissions because it is playing an increasingly more important role in waste management. MSW incineration in China has much higher emission rates of dioxins than in the developed countries, partially resulting from the gaps in the technologies of incineration and flue gas cleaning. Moreover, the current management policies and practices also contribute significantly to the problem. We recommend lowering dioxin emission standard, strengthening fly ash management, and improving regulation enforcement to reduce dioxin releases into the environment from MSW incineration. We also propose that alternative strategies should be considered on dioxin control and call for an expansion of economic instruments in waste management to reduce waste generation and thus the need for incineration.  相似文献   
977.
印制电路板酸性蚀刻废液的膜电解再生   总被引:1,自引:0,他引:1  
高度精细化线路和高层数印制电路板产量的增加,导致酸性蚀刻废液的排放量越来越大,对环境的负荷也随之增大.介绍了酸性蚀刻废液膜电解再生的基本原理,进行了中试规模的应用研究,并与其他电解再生方法进行技术与经济比较分析.结果表明,在槽电压为5V、电解时间为2h的条件下,酸性蚀刻废液的氧化还原电位由480 mV升至540mV,所...  相似文献   
978.
超临界CO_2流体环境中线路板分层实验分析   总被引:2,自引:0,他引:2  
在超临界CO2流体环境下,当温度达到240℃以上时,印刷线路板就会发生分层现象。同时,在实验中发现在非超临界流体环境下,当温度达到260℃以上时,线路板也会发生分层现象。从线路板粘接材料发生热解反应的角度出发,在对比超临界CO2流体环境下与非超临界流体环境下的线路板分层效果的基础上,对超临界CO2流体环境下的线路板分层做出合理分析,最后发现临界CO2流体对线路板分层过程有促进作用,并对其分层效果有优化作用。  相似文献   
979.
Multiple isoenzymes of the detoxification enzyme family Glutathione S-transferase are expressed in the brine shrimp Artemia. The number of the major ones detected in crude extract by means of chromatofocusing varied between three and four, depending on the age. Two isoenzymes, one alkaline and one neutral (with corresponding isoelectric points of 8.5 and 7.2) appear to be dominant in all three developmental stages studied, (24, 48, and 72 h after hatching). Culturing Artemia for 48 h after hatching, in artificial sea water prepared by municipal wastewater effluent resulted to significant alterations of the isoenzyme profile. In comparison to organisms cultured for the same period of time in artificial sea water prepared by filtered tap water, the expression of the alkaline isoenzyme decreased by 62% while that of the neutral isoenzyme increased by 58%. Furthermore, the enzyme activity of the major isoenzyme of the acidic area increased by more than two folds. It is worth mentioning that although the specific activity of the total enzyme in the whole body homogenate was elevated, no statistically significant alteration of the Km value was observed. These findings suggest that study of the isoenzyme profile of Glutathione S-transferase may offer high sensitivity in detecting environmental pollution and needs to be further investigated.  相似文献   
980.
Variation with depth and time of organic matter (carbon, nitrogen, phosphorus), inorganic pollutant (mercury), as well as bacterial abundance and activity, were investigated for the first time in sediment profiles of different parts of Lake Geneva (Switzerland) over the last decades. The highest organic contents (about 32%), mercury concentration (27 mg kg−1), bacterial abundance (in order of 9 × 109 cell g−1 dry sediment), and bacterial activity (1299 Relative Light Units (RLU)) were found in the highly polluted sediments contaminated by the waste water treatment plant (WWTP) discharge, which deposited during the period of cultural eutrophication. Such data, which contrast with the other sampled sites from deeper and more remote parts of the lake, prove that the organic matter and nutrients released from the municipal WWTP have considerable effects on bacterial abundance and activities in freshwater sediments. In fact, the relatively unpolluted deepwater sites and the coastal polluted site show large synchronous increases in bacterial densities linked to the anoxic conditions in the 1970s (lake eutrophication caused by external nutrient input) that subsequently increased the nutrient loading fluxes. These results show that the microbial activities response to natural or human-induced changing limnological conditions (e.g., nutrient supply, oxygen availability, redox conditions) constitutes a threat to the security of water resources, which in turn poses concerns for the world’s freshwater resources in the context of global warming and the degradation of water quality (oxygen depletion in the bottom water due to reduced deep waters mixing). Moreover, the accumulation of inorganic pollutants such as high mercury (methyl-mercury) concentration may represent a significant source of toxicity for sediment dwelling organisms.  相似文献   
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