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191.
选取嘉兴市秀洲区和海宁市为研究对象,以乡镇区划为研究单元,采用综合源强估算法和GIS软件,对处理设施的氨氮(NH3-N)、总磷(TP)、化学需氧量(COD)排放强度进行定量估算和空间分析.结果表明,秀洲区处理设施的NH3-N和COD排放强度高于海宁市,而TP排放强度与海宁市差不多.秀洲区内,洪合镇各污染物的排放强度均最高;海宁市内,盐官镇NH3-N排放强度最高,许村镇TP和COD排放强度最高.采用因子分析法和加权指数法计算排污权重,再结合生态敏感性评价和环境功能区划,筛选出运维和监管优先控制区.秀洲区内,洪合镇、王江泾镇、油车港镇被划分为优先控制区,该优先控制区内处理设施数量占比27.87%,排污权重占比72.42%,通过重点监管17.66%的设施,可监管秀洲区59.98%的污染物排放.海宁市内,长安镇、许村镇、海洲街道、盐官镇、袁花镇被划分为优先控制区,该优先控制区内设施数量占比69.10%,排污权重占比71.23%,通过重点监管16.85%的设施,可监管海宁市43.54%的污染物排放.研究结果可为提高设施的运维监管效率提供技术支撑.  相似文献   
192.
以脱水污泥为原料针探究对其水热液化(HTL)制取生物油的影响.结果表明,胞外聚合物(EPS)的释放可以促进有机物在高温时断链成分子量较高的有机质,促进生物油的形成.与原污泥相比,亚临界水(SCW)预处理会促进脱氨基反应,生物油中的氮含量降低51.74%;十六烷基三甲基溴化铵(CTAB)预处理则促进了19.3wt%的有机物转移至油相中,同时生物油中的酸含量降低13.49%;CTAB-SCW联合预处理后,生物油收率提升了66.92%,醇含量提升28.32%.联合预处理中酯交换反应是主反应,同时亲核反应、氧化反应和消除反应也显著增强.  相似文献   
193.
生物沥浸耦合类Fenton氧化调理城市污泥   总被引:4,自引:3,他引:1  
采用生物沥浸耦合类Fenton氧化工艺对城市污泥进行了调理研究.结果表明,在升华硫和Fe SO4·7H2O投量分别为3g·L-1和8 g·L-1时,污泥p H从6.9降至2.5约需1 d,满足类Fenton氧化的适宜酸性条件.生物沥浸处理后,污泥挥发性固体(VS)减少率为13.4%,污泥比阻从3.1×109s2·g-1降至1.5×109s2·g-1,降低51.6%,但仍属于难脱水污泥.沥浸污泥继续经类Fenton氧化调理,调理的最佳H2O2投量和反应时间分别为3.3 g·L-1和60 min.处理后污泥VS减少率为30.8%,污泥比阻和滤饼含水率分别为1.9×108s2·g-1和76.9%,污泥比阻降低93.9%,污泥脱水性能和稳定性能得到显著提高.此外,该联合工艺对污泥的调理效果优于类Fenton氧化单独调理.  相似文献   
194.
/ It has been suggested that the general public should be moreinvolved in environmental policy and decision making. It is important forthem to realize that they will have to live with the consequences ofenvironmental policies and decisions. Consequently, policy makers shouldconsider the concerns and opinions of the general public before makingdecisions on environmental issues. This raises questions such as: How can weintegrate the perceptions and reactions of the general population inenvironmental decisions? What kind of public participation should weconsider? In the present study, using a new regional ecosystem model, weattempted to integrate these aspects in its decision making model byincluding the formation of an advisory committee to resolve problems relatedto waste management. The advisory committee requested the activeparticipation of representatives from all levels of the community: economic,municipal, and governmental intervenors; environmental groups; and citizens.Their mandates were to examine different management strategies available inthe region, considering all the interdisciplinary aspects of each strategy,elaborate recommendations concerning the management strategies that are mostsuitable for all, and collaborate in communication of the information to thegeneral population. The results showed that at least in small municipalitiessuch an advisory committee can be a powerful tool in environmental decisionmaking. Conditions required for a successful consultation process, such aseveryday lay language and the presence of a facilitator other than ascientific expert, are discussed.KEY WORDS: Public consultation; Environmental policies;Interdisciplinary aspects; Municipal sewage sludge management; Generalpopulation; Decision-making process  相似文献   
195.
ABSTRACT: In 1983, the City of Indianapolis, Indiana, completed construction of advanced wastewater treatment (AWT) systems to enlarge and upgrade its existing Belmont Road and South port Road secondary treatment plants. A nonparametric statistical procedure, a modified form of the Wilcoxon-Mann-Whitney rank-sum test, was used to test for trends in water quality at two upstream and two downstream sites on White River and at the two treatment plants. Results comparing the pre- (1978–1980) and post- (1983–1986) AWT periods show statistically significant improvements in the quality of the treated effluent and of the White River downstream from the plants. Water quality at sites upstream from the city was relatively constant during the period of study. Total ammonia (as N) decreased 14.6 mg/L and BOD5 (five-day biochemical oxygen demand) decreased 10 to 19 mg/L in the two effluents. Total ammonia in the river downstream from the plants decreased 0.8 to 1.9 mg/L and BOD5 decreased 2.3 to 2.5 mg/L. Nitrate (as N) increased 14.5 mg/L in the plant effluents and 2.0 to 2.4 mg/L in the river because of in-plant nitrification. Dissolved oxygen concentration in the river increased about 3 mg/L because of reduced oxygen demand for nitrification and biochemical oxidation processes.  相似文献   
196.
都市农业生态系统中污水资源化利用   总被引:1,自引:0,他引:1  
文章介绍了都市农业生态系统中的污水处理工艺和资源化利用方案,并对回用过程中的水质状况进行了连续监测与分析,结果表明,主要污染物CODCr、BOD5、浊度、TN的去除率均达到90%以上。再生水完全可以满足系统内农业灌溉的要求,每年可减少50%的地下水开采量,且提供了良好的景观资源。蟹岛生态度假村以生活污水处理为中心的水资源循环利用方式,为污水资源化利用工程作了有益的尝试并取得了良好的效果。  相似文献   
197.
对上海某乡因施用大量污泥而造成的污染状况作跟踪调查研究和质量评价。研究对象为土壤、水稻和蔬菜,被研究的污染元素为Cd、Zn、Cu、Ph、Ni、Cr、Hg和As.结果表明,该乡土壤为复合污染,Cd、Zn、Cu是主要污染元素.污泥施用越多的地区,水稻、蔬菜受污染就越严重,尤以Cd污染最为突出,超过了允许卫生标准。确定了污染村、污染程度和污染面积。  相似文献   
198.
硝化菌与膜生物反应器结合处理生活污水中氨氮   总被引:3,自引:0,他引:3  
研究了硝化菌与膜生物反应器结合处理生活污水中氨氮,实验用水采用食堂与化粪池混合水,实验装置采用膜生物反应器,进水氨氮在4mg/L左右,出水氨氮值接近0,实验结果表明出水能够达到国家工业冷却回用水的指标要求,同时COD也降至30mg/L以下,能满足回用要求。  相似文献   
199.
Marine pollution and coastal degradation have become serious development issues in the Caribbean. Early evidence of marine pollution was mainly anecdotal, but within the last 10--15 years, work conducted by universities and research institutions in the Region has provided the beginnings of a database that identifies several common marine pollution problems. The United Nations Environment Programme (UNEP), the Intergovernmental Oceanographic Commission (IOC) and the Pan American World Health Organization (PAHO/WHO) have also been instrumental in co-ordinating several marine pollution studies. In the English-speaking Caribbean, the University of the West Indies, the Institute of Marine Affairs in Trinidad and Tobago, and the Caribbean Environmental Health Institute located in St Lucia, have taken a lead role in identifying marine pollution problems in their Sub-Region. For the Wider Caribbean a database for petroleum pollution and marine debris has been developed. Land-based sources of marine pollution have been identified as a major problem, with several hot spots identified in mainland countries and in some of the larger industrialised islands. Organic and nutrient pollution, particularly from sewage, is most widespread and is possibly the most serious marine pollution problem in the Caribbean. A lack of capital investment funds to install the appropriate infrastructure to deal with sewage and other liquid effluents is a major stumbling block to solving the problem of marine pollution in the Caribbean. Other factors include political will and administrative and legal structures to regulate human development activities.  相似文献   
200.
通过温室盆栽试验研究不同比例粉煤灰钝化污泥人工土壤上高麦草的生长发育及营养状况,试验结果表明:土壤中加入粉煤灰钝化污泥显著增加了高麦草的干物重.脱水污泥加入其鲜重的10%粉煤灰钝化后再按1∶1和1∶5体积比与土壤混合配成的人工土处理和加入其鲜重的35%粉煤灰钝化后再按1∶1体积比与土壤混合配成的人工土处理高麦草的产量都显著高于自然土壤施用化肥的处理,高麦草的发芽率也不受影响.随着粉煤灰加入量的增加,高麦草地上部Ca,Mg和B的浓度(w/%或w/mg.kg-1)增加而K,Fe,Mn和Zn的浓度下降,高麦草根中Fe,Mn,Cu和Zn的浓度显著高于其地上部中的浓度.所有粉煤灰钝化后污泥人工土壤高麦草都没有出现N和P的缺乏和重金属毒害,说明合适比例的粉煤灰钝化污泥人工土壤是高麦草的良好生长介质.  相似文献   
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