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811.
812.
对辽宁省鞍山市某生活垃圾卫生填埋场的晚期垃圾渗滤液进行预处理,选择MgO和磷矿粉两种矿物,利用共沉淀法去除垃圾渗滤液中的氨氮,用于制备磷铵镁复合肥,实现垃圾渗滤液的资源化利用。实验结果如下:MgO与磷矿粉配合使用,能够较好地去除垃圾渗滤液中COD和氨氮。采用MgO、磷矿粉共沉淀法生成磷铵镁复合肥具有可行性,同时可为后续生化处理创造良好的条件;在给定条件下(氨氮浓度1200 mg/L,COD 3180 mg/L),垃圾渗滤液COD去除的最优实验条件为MgO添加量5.0 g/L、磷矿粉添加量100 g/L,反应时间4 h,处理后COD去除率为62.1%,氨氮去除率为87.5%;氨氮去除的最优实验条件为MgO添加量10 g/L、磷矿粉添加量60 g/L、反应时间4 h,处理后COD去除率为42.1%,氨氮去除率为96.1%。 相似文献
813.
Jinfeng Bai Chunwang Yang Zhenning Zhao Xiangyun Zhong Yaru Zhang Jun Xu Bai Xi Hongchun Liu 《环境科学学报(英文版)》2013
Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m3 to 1.05 ton/m3, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m3; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600°C. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m3 to 1.05 ton/m3, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope. 相似文献
814.
供水管网是影响供水水质的重要因素,特别是在拥有复杂供水管网的现代化大都市。以国内某现代化大都市供水管网为研究对象,该市拥有普通自来水供水系统和饮用净水供水系统,分别建立了水质监测系统,并根据提出的供水管网水质监测点布置原则确定了水质监测点的位置、数量及监测频率、指标;通过从2009年6月至2010年1月为期8个月的水质监测,共采集了560份水样数据,据其对该大都市的供水管网水质进行了分析评价。结果显示:供水管网对普通自来水及饮用净水水质都会产生不良影响;普通饮用水经过管网传输,细菌总数升高甚至超标,特别是在供水管网末梢及两水厂供水交界处;饮用净水的不合格项目为细菌总数和浑浊度,其在距离水厂越近的区域水质越好。 相似文献
815.
Selection of water source for water transfer based on algal growth potential to prevent algal blooms
Water transfer is becoming a popular method for solving the problems of water quality deterioration and water level drawdown in lakes. However, the principle of choosing water sources for water transfer projects has mainly been based on the effects on water quality, which neglects the influence in the variation of phytoplankton community and the risk of algal blooms. In this study, algal growth potential (AGP) test was applied to predict changes in the phytoplankton community caused by water transfer projects. The feasibility of proposed water transfer sources (Baqing River and Jinsha River) was assessed through the changes in both water quality and phytoplankton community in Chenghai Lake, Southwest China. The results showed that the concentration of total nitrogen (TN) and total phosphorus (TP) in Chenghai Lake could be decreased to 0.52 mg/L and 0.02 mg/L respectively with the simulated water transfer source of Jinsha River. The algal cell density could be reduced by 60%, and the phytoplankton community would become relatively stable with the Jinsha River water transfer project, and the dominant species of Anabaena cylindrica evolved into Anabaenopsis arnoldii due to the species competition. However, the risk of algal blooms would be increased after the Baqing River water transfer project even with the improved water quality. Algae gained faster proliferation with the same dominant species in water transfer source. Therefore, water transfer projects should be assessed from not only the variation of water quality but also the risk of algal blooms. 相似文献
816.
保护野骆驼及栖息环境是我们保护区人共同的责任,呼吁全社会都来关心和担负起这份光荣的使命,一旦这个物种灭绝了,我们的子孙们只能从教科书中了解它、看到它,这是我们这一代野骆驼保护区工作者的失职,也是我们这一代人犯下的罪过。 相似文献
817.
采用黄磷乳浊液为吸收剂,考察了黄磷浓度、反应温度、搅拌速度、氧气浓度、烟气流量等影响因素对脱硝率的影响,并且通过添加碳酸钙进行改性,提高了体系的脱硝率。结果表明,脱硝率随黄磷浓度增大、反应温度升高、搅拌速度增大而升高;随烟气流量的增大而下降;加入碳酸钙改性可以明显提高体系脱硝效果;烟气流量400 m L/min,反应温度50℃,搅拌速度1 200 r/min,氧气浓度12%,黄磷浓度6 g/L,碳酸钙浓度2 g/L的条件下,处理NO浓度为0.06%的烟气,反应30 min体系脱硝率可达到84.76%。 相似文献
818.
采用多元统计主成分分析方法对城市河流邕江8个监测断面的高锰酸盐指数、化学需氧量、生物需氧量、溶解氧等10个水质指标进行分析计算.结果表明:(1)提取占总方差86.99%的3个因子来反映邕江水体的污染程度:①以氨氮、高锰酸指数、总磷、溶解氧、石油类、化学需氧量等有机污染因子控制;②粪大肠菌群和酸碱性控制;③重金属也存在于邕江.(2)上游水质明显优于下游,表明城区产生的工业与生活污水对邕江水质产生了明显影响. 相似文献
819.
820.