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991.
The useful life of consumer electronic devices is relatively short, and decreasing as a result of rapid changes in equipment features and capabilities. This creates a large waste stream of obsolete electronic equipment, electronic waste (e-waste).Even though there are conventional disposal methods for e-waste, these methods have disadvantages from both the economic and environmental viewpoints. As a result, new e-waste management options need to be considered, for example, recycling. But electronic recycling has a short history, so there is not yet a solid infrastructure in place.In this paper, the first half describes trends in the amount of e-waste, existing recycling programs, and collection methods. The second half describes various methods available to recover materials from e-waste. In particular, various recycling technologies for the glass, plastics, and metals found in e-waste are discussed. For glass, glass-to-glass recycling and glass-to-lead recycling technologies are presented. For plastics, chemical (feedstock) recycling, mechanical recycling, and thermal recycling methods are analyzed. Recovery processes for copper, lead, and precious metals such as silver, gold, platinum, and palladium are reviewed. These processes are described and compared on the basis of available technologies, resources, and material input–output systems.  相似文献   
992.
FeS引发储油罐着火温度动态变化曲线的研究   总被引:11,自引:2,他引:11  
储油罐着火事故被推测是由硫腐蚀产生的FeS氧化引起的。笔者阐述了储罐中FeS形成的原因 ,并采用自然发火绝热测试系统对FeS自然氧化进行 1 9h的跟踪实验 ,观察FeS绝热氧化过程中温度动态变化特性。实验发现 ,FeS氧化由诱导氧化期、中速氧化期和加速氧化期 3个阶段组成。诱导氧化期是积蓄能量 ,激发FeS活性的过程 ,试样温度基本未发生变化 ;中速氧化期是FeS试样表面的分子活性被激发 ,与FeS试样表面吸附的氧气发生氧化反应的过程 ,温度增加较慢 ;加速氧化期是FeS分子内部的活性被激活并进行氧化反应的过程 ,温度迅速升高。结果证明 :随着反应的进行 ,温度随反应时间变化的幅度越来越大 ,氧化反应的反应热不能及时散开而急剧地积累 ,温度急剧地升高 ,将引起油品自燃。此外 ,通过X衍射图和氧化升温曲线证明 ,水是影响FeS氧化的重要因素。  相似文献   
993.
文章从灰色关联方法选择及分析原理入手,用某炼油厂2002全年的污水处理监测数据进行了灰色关联分析,通过运算分析得出了大量污水处理的关联数据。找出了影响出水水质指标的关键因素,对指导炼油污水进行分级控制做了有益的尝试。  相似文献   
994.
高铁酸盐氧化絮凝去除含油污水中的油   总被引:3,自引:0,他引:3  
油田产出的油、水经分离后会产生大量的含油污水,选用高铁酸钾对污水进行处理已成为人们关注的一个问题。用荧光比色法测定非均相固-液悬浮体系中油含量的实验证明:(1)高铁酸盐在含油污水中的初始反应速度快,可将大部分有机物氧化;(2)氧化法处理含油污水受多种因素的影响;(3)高铁直接氧化和芬顿氧化法均可比较彻底地处理油田含油污水。用高铁氧化法处理含油污水技术上很有发展前景,各种浓度的污水经处理后都可达到国家排放标准。  相似文献   
995.
ABSTRACT: Farms that once spread only manures are now also applying sewage biosolids (sludge) and/or other wastes such as those from food processing. The objective of this study was to monitor environmental impacts at a dairy farm applying these materials. Fields were selected representing recent waste applications of manure (M1, M2), sewage biosolids (B1, B2), or fertilizer only control (F1, F2), although most fields had historical biosolids applications. Fields representing each treatment were not experimental replicates because of varying applications and soil characteristics. Septage and food processing wastes were also applied. Soil percolates were collected with wick lysimeters. Runoff was sampled at seven stream sites. Test field soils and alfalfa (Medicago sativa) were analyzed for trace elements. Cumulative trace metal loadings were low, at most only 1 percent of USEPA Part 503 limits. Surface soil enrichment was most evident for Mo, P, and S. Alfalfa tissue showed no trends of concern. The B2 site had the greatest percolate concentrations for 6 of 13 elements. Percolate Cu was somewhat elevated at Sites M1, M2, B2, and Fl. Percolate sodium was elevated on all M and B fields and sulfur was greatest at M2, B1, and B2. Soluble orthophosphate correlated with stream discharge during intensive monitoring of Stream Sites S1 (fertilizer) and S2 (biosolids). Peaks in S2 streamwater Mo lagged large runoff events by five days. Total streamwater export of Cu, Na, Mo, and soluble P were greater from the S2 biosolids subwatershed than from the S1 fertilizer subwatershed. Percolate concentrations exceeded corresponding streamwater concentrations in most cases.  相似文献   
996.
填埋场场地复用技术与展望   总被引:4,自引:0,他引:4  
刘丹  李启彬 《四川环境》2004,23(1):15-17
城市垃圾卫生填埋场场地复用技术是一种能增大填埋场填埋能力,避免过高的填埋场地费用的新方法。该技术在德国和美国的实践都已取得了成功。为使该技术能在我国得到推广和应用,文中介绍了该技术的实施条件,列举了部分应用实例,分析了该技术的优势及潜在问题,最后对其在我国的应用前景进行了展望。  相似文献   
997.
我国废电池的回收与处理   总被引:5,自引:0,他引:5  
本文详细介绍了国内外常见的各种废电池的种类、有害成分,处理方法,分析了目前我国在度电池回收处理过程中所存在的诸多问题,并有针对性的提出建议。  相似文献   
998.
The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas, the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LMNRA), to provide information for NPS oil and gas management plans. Because NVCS landcover classifications did not exist for these two areas prior to this study, we created landcover classes, through intensive ground and aerial reconnaissance, that characterized the general landscape features and at the same time complied with NVCS guidelines. The created landcover classes were useful for the resource management and were conducive to classification with optical remote sensing systems, such as the Landsat Thematic Mapper (TM). In the LMNRA, topographic elevation data were added to the TM data to reduce confusion between cliff, high plains, and forest classes. Classification accuracies (kappa statistics) of 89.9% (0.89) and 88.2% (0.87) in PINS and LMNRA, respectively, verified that the two NPS landholdings were adequately mapped with TM data. Improved sensor systems with higher spectral and spatial resolutions will ultimately refine the broad classes defined in this classification; however, the landcover classifications created in this study have already provided valuable information for the management of both NPS lands. Habitat information provided by the classifications has aided in the placement of inventory and monitoring plots, has assisted oil and gas operators by providing information on sensitive habitats, and has allowed park managers to better use resources when fighting wildland fires and in protecting visitors and the infrastructure of NPS lands.  相似文献   
999.
用蒸汽驱油开采稠油,污水不能回注,外排污水中石油类和悬浮物对环境造成污染。为解决这一问题,河南油田在引进设备的基础上,对稠油污水处理系统进行了改进,利用原有设备,增加了用简单气浮选装置处理稠油污水工艺,只需增加一台离心泵。该工艺投资少,运行可靠,效率高,适用性强。但要注意控制微气泡的大小等。  相似文献   
1000.
浮选机从采油污水中除油的若干问题   总被引:3,自引:0,他引:3  
浮选机应用过程中出现了一些问题,有的已停用、报废,以至拆除。文中分析了各方面的因素,例如:机械方面的问题、液面高度失控问题、浮选除油的影响因素、以及浮选除油的附带作用等。总体来说,浮选机除油的效果是肯定的,通过改进其性能,处理效果还能提高,出现的问题都不难解决。所以,浮选机的应用还是一种值得考虑的除油方法。  相似文献   
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