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511.
活性炭吸附处理锂电池厂含酯废水及微波再生实验   总被引:2,自引:0,他引:2       下载免费PDF全文
采用活性炭吸附的方法对锂电池产生的含酯废水进行预处理,研究了吸附时间、初始pH值和活性炭投加量对废水COD去除的影响.吸附饱和后的活性炭用微波进行再生,考察了辐照时间、微波功率及再生次数对活性炭再生效果的影响.结果表明,当活性炭投加量为10g/L时,吸附60min,含酯废水的COD去除率为69.5%,可生化性从原水的0.05提高到0.25.当微波功率为420W、辐照时间为6min时,活性炭可被有效地再生,再生效率高达98.0%,活性炭损失率约为5.2%.再生前后活性炭的红外光谱图表明,活性炭表面官能团发生了变化,促进活性炭对污染物质的吸附.  相似文献   
512.
Wastes are usually stocked in waste disposals without any pre-treatment. Runoff waters lead to the formation of leachates containing mineral and organic pollutants. In order to prevent groundwater contamination, a double barrier is placed on the landfill bottom. The first one is an active barrier made up of a draining system and a geomembrane, and the second one, consisting of a clay liner allowing pollutant retention, is considered as a passive system. The aim of this work is to evaluate the complexation impact on the organic and inorganic retention. Percolations on columns filled with clay are performed, which allow a better knowledge of the transfer of metallic pollutants, complexed or not, through a model porous media, considering charge and conditional stability of complexes.  相似文献   
513.
It is widely known that human exposure to mercury vapor can cause neurological and neuropsychological deterioration. We have investigated if a population of Chilean artisanal gold-mining workers heavily exposed to elemental mercury (Hg0) display neurological and neuropsychological impairment. Male volunteers occupationally exposed to Hg0 (“gold miners”, n = 35) were recruited and compared with a group of unexposed workers (n = 40). Blood specimens were obtained from both groups for total mercury quantification. Upon neurological examination, 71% of the “gold miners” group showed abnormalities expressed as frontal impairment, tremor, or simultaneously frontal impairment, parkinsonism, and pyramidal syndrome. In contrast, only 16% of the individuals in the control group displayed neurological abnormalities. The “gold miners” group also showed impairment of the neuropsychological performance and the distribution of abnormal scores for almost all the neuropsychological tests applied was significantly higher in this group compared to the control group. Educational level, alcohol intake, and smoking habits did not influence the outcome of the neurological or neuropsychological examinations. Finally, despite that the higher blood mercury concentrations were found in the “gold miners” group, they were not significantly different from the values obtained in the control group.  相似文献   
514.
锂离子电池用新型复合聚合物电解质膜的性能研究   总被引:2,自引:0,他引:2  
聚合物电解质膜是影响锂离子电池性能的重要因素,通过对聚合物的改性,能够改善聚合物电解质膜综合性能.本文以偏氟乙烯-六氟丙烯共聚物[P(VDF-HFP)]为基,以N甲基吡咯烷酮(NMP)作溶剂,γ-丁内酯(γ-BL)作添加剂,用倒相湿法制备出复合聚合物电解质膜,并对其离子传递、膜结构和电化学性能进行了研究.用限制扩散方法测定了该电解质膜的锂离子扩散系数为5.68×10-10 cm2·s-1;用稳态极化法测定了该电解质膜的迁移数为0.61;用交流阻抗法测得该电解质膜的室温最高电导率可达1.73×10-3S·cm-1.测试结果表明,该聚合物电解质膜具有较好的离子传输性质和电化学性能.  相似文献   
515.
The New Lead. Belt of southeastern Missouri has recently become the largest lead producing region of the world. The impact of this rapid development on the previously rural and undeveloped region of the Missouri Ozarks is the subject of a continuing interdisciplinary study. Since the industrial development began, there have been a number of nuisance biological blooms in several of the small streams receiving effluent from the mines and mills. The major constituents of the problem algal growths were identified and found to include: Cladophora, Oscillatoria, Mougeotia, Zygnema, Spirogyra, Cymbella, and a variety of other stalked and non-stalked diatoms. Secondary blooms of Sphaerotilus were observed to reach problem proportions in some streams, particularly in the autumn. Finely ground rock flour and mineral particles escaping from tailings dams were found to be trapped by the stream vegetation. Concentrations of lead, zinc, copper, and manganese in the algal and bacterial mats were found to be inversely related to distance downstream from the tailings dams. Consumer organisms, including crayfish, snails, aquatic insects, tadpoles, minnows and larger sunfish were analyzed to determine the extent of dissemination and concentration of the heavy metals through food chains. Preliminary results indicated insignificant concentrations of heavy metals in those consumer organisms studied, though in at least one problem stream the normal consumer organisms mentioned were markedly reduced in numbers.  相似文献   
516.
重庆市巴县,长寿县水稻和小麦的重金属污染   总被引:1,自引:0,他引:1  
重庆市巴县和长寿县的部分水稻和小麦已经受到重金属汞、镉、铅的污染,污染程度长寿县〉巴县,小麦〉水稻,铅〉汞〉镉。污染的主要原因是环境污染所造砀 ,尤其是重化工业所在场镇附近污染特别显著,汞和铅污染有加重趋势,镉污染有所减轻,提出了对策建议。  相似文献   
517.
/ Air, soil, and water samples were collected throughout the Republic of Armenia both before and after its independence from the Soviet Union in 1991. Reported analyses of those samples indicated that levels of several trace metal concentrations (Ag, Cd, Cr, Cu, Mo, Ni, Pb, Ti, and Zn) exceeded the maximum allowable concentrations established by the former Soviet Union (FSU) and subsequently adopted by Armenia. Although industrial production has declined by more than 80% since the 1980s, the economy is improving and there is potential for a significant increase in the generation of industrial metal emissions. These include automobile emissions, which are now considered to be the primary source of atmospheric lead. Historically, the Soviet Union did not strictly enforce environmental standards, and Armenia is now faced with the resulting environmental problems and the associated risks to public health. Since some trace metal concentrations may be at or near potentially toxic levels, there is a need to accurately assess the extent of metal contamination in order to devise cleanup plans and develop long-term environmental protection and public health strategies in Armenia.  相似文献   
518.
某型军用锂离子电池低温环境适应性   总被引:3,自引:1,他引:2  
目的研究低温环境条件下温度对某型军用方形锂离子电池放电性能的影响。方法参照标准GB/T 18287,在常温下将锂离子电池进行充电,再在高低温潮湿试验箱中按设定低温条件利用电池测试仪进行放电性能测试,并将不同温度测试结果利用加速模型结合Arrenhenius方程进行拟合。结果该型军用锂离子电池放电容量随温度下降而降低,在-30℃温度条件下电池的放电容量相当于室温放电容量的20.9%,并在低于-40℃温度条件、2.5 V截止电压下无法放电。结论通过低温条件放电性能测试,并对温度条件和放电容量进行建模,得出绝对温度倒数与电池容量保留率对数在25~-35℃温度区间内分两段成线性相关。  相似文献   
519.
目前废旧电池污染对人类健康及环境造成的危害越来越受到人们的关注.结合目前国内废旧锂电池回收概况及区域废旧锂电池回收的实地调研情况,了解废旧锂电池的回收再利用现状及人们对废旧锂电池的认识,分析锂电池的再利用价值.同时,结合电池品种羔异的特性,设计出针对性强、可行性高的废弃锂池回收体系;通过分析锂电池工作的基本工作原理、使用特性及电池材料组成成分,提出一些延长锂电池使用寿命、增加使用周期的方法.  相似文献   
520.
目的解决中重型车辆装备在高原高寒环境下蓄电池充放电性能降低,起动电量供应不足的问题。方法采用燃油空气加热器对车用铅酸蓄电池进行加热,同时运用专用保温箱进行保温,保持蓄电池内部温度在正常工作范围,确保其在低温环境下的充放电性能。结果使用蓄电池加热和保温装置,可将蓄电池电解液温度升至常温。在-25℃环境条件下,可以提高蓄电池放电量65%左右;在-41℃环境条件下,可以提高蓄电池放电量110%左右。结论蓄电池加热和保温装置可以有效提高其低温环境下充放电性能,使车用蓄电池在低温环境中可以有效提供发动机起动及各种起动辅助装置用电,为高原高寒地域中重型车辆的起动与运行提供有效保障。  相似文献   
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