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941.
用Na_2CO_3催化焙烧法将CuS转化为Cu。最佳的转化条件;反应温度为750℃,CuS:Na_2CO_3(摩尔比)为1:2,在空气中反应90min。CuS的转化率可达到99%。  相似文献   
942.
娄玉良  苑士波 《化工环保》1995,15(3):167-170
对氰化钠生产中的聚合废料进行了吸附试验和氰化钠含量分析,试验结果表明,聚合废料中含有28%左右的氰化钠,其中黑褐色杂质可用活性炭吸附脱除。生产规模试验证明,用聚合废料为原料生产的硫氰酸钠,产品质量可达到装置设计指标,满足腈纶装置的使用要求。  相似文献   
943.
塔里木沙漠油田开发工程的环境影响评价   总被引:1,自引:0,他引:1  
塔里木是一个内陆封闭盆地,是世界第二大流动沙漠,它具有丰富的油气资源,目前正在积极开发中。在油气田开发过程中必须做环境影响评价,文中介绍了沙漠环境及生态状况,在沙漠区域必须以水域和生态环境影响评价为重点,评价结果应提出固沙、防沙和保护自然生态等一系列防治措施和对策。  相似文献   
944.
天然放射性物质及环境问题   总被引:1,自引:0,他引:1  
天然放射性物质(naturallyoccurringradioactivematerials,简称NORM)广泛存在于地层中,当石油或天然气从地下开采出来时,痕量的天然放射性核素如镭、氧等也随之采出,并分别集中于管道及设备的垢层或天然气加工装置的内壁薄膜上。文章在对外文资料调研的基础上,将NORM的有关知识、存在场所、对人体潜在的危害途径及有关辐射防护方法进行了介绍。  相似文献   
945.
An oil spill polluted site at Ogbodo-Isiokpo in Ikwere Local Government Area of Rivers State in southern Nigeria, was identified for study following three successive reconnaissance surveys of oil fields in the Agbada west plain of Eastern Niger Delta. A sampling area of 200 m × 200 m was delimited at the oil spill impacted site using the grid technique and soils were collected at surface (0–15 cm) and subsurface (15–30 cm) depths from three replicate quadrats. A geographically similar, unaffected area, located 50 m adjacent to the polluted site, was chosen as a control (reference) site. Total extractable hydrocarbon contents of the polluted soils ranged from 3.02–4.54 and 1.60–4.20 mg/kg (no overlap in standard errors) at surface and subsurface depths respectively. The concentrations of two “diagnostic” trace heavy metals, nickel (Ni) and vanadium (V), which are normal constituents of crude oil, were also determined in the soils by atomic absorption spectrophotometric method after pre-extraction of cations with dithionite–citrate carbonate. Ni varied from 0.15 to 1.65 mg/kg in the polluted plots and from 0.18 to 0.82 mg/kg in the unpolluted plots; vanadium varied from 0.19 to 0.70 mg/kg in the polluted plots and from 0.14 to 0.38 mg/kg in the unpolluted plots. Ni and V were more enhanced (p < 0.05) in the oil-polluted soils, especially at subsurface depth. Whilst the oil spillage could be said to be indirectly responsible for the enhanced concentrations of nickel and vanadium via the injection and availability of the petroleum hydrocarbons that might have increased the activities of biodegradation on site, the physico-chemical properties of the soils and inherent mobility of metals, as well as the intense rainfall and flooding that characterized the period of study, may have also contributed, at least in part, to these enhanced concentrations. Such levels of Ni and V may result to enhanced absorption by plants, which may bring about possible bioaccumulation in such plants and the animals that depend on them for survival and all of these may lead to toxic reactions along the food chain.  相似文献   
946.
废旧干电池的环境污染防治及回收利用   总被引:5,自引:0,他引:5  
王颖 《干旱环境监测》2002,16(2):113-115
介绍了各种干电池的基本化学组成,分析了废旧干电池污染环境的主要途径及对人类的危害,并就回收利用问题提出建议。  相似文献   
947.
The lakes in KillarneyProvincial Park, located 40–60 km southwest ofSudbury, Ontario, were some of the first lakesin North America to be acidified by atmosphericpollutants. Acidification affected thousandsof fish and invertebrate populations in dozensof lakes. Since the 1970's, water quality hasimproved in response to atmospheric pollutionreductions and some lakes have alreadyrecovered to approximately their pre-industrialpH levels, as inferred from diatom microfossilsin lake sediments. Since the 1970's, fishspecies richness has not changed substantially,but zooplankton species richness has increasedin acidified lakes. The critical sulphur load,the amount of SO2-derived acid depositionthat can occur while still maintaining suitable water quality, was estimated to beexceeded in 38% of the park area in 1997. Depending on which of four possible NorthAmerican emission control scenarios (CLR =currently legislated reduction; CLR + 25%; CLR+ 50%; CLR + 75%) is achieved by 2010, theprojected critical loads will be exceeded inabout 0-30% of the park area in the future. There are many factors that can affectbiological recovery rates of damaged lakes, butit is expected that biological recovery willlag considerably behind observed chemicalrecovery rates.  相似文献   
948.
Aquatic acidification by deposition of airborne pollutants emerged as an environmental issue in southeastern Canada during the 1970s. Drawing information from the extensive research and monitoring programs, a sequence of issue assessments demonstrated the necessity of reducing the anthropogenic emissions of acidifying pollutants, particularly sulphur dioxide (SO2). The 1991 Canada-U.S. Air Quality Agreement (AQA) was negotiated to reduce North American SO2 emissions by 40% relative to 1980 levels by 2010, and at present, both countries have reduced emissions beyond their AQA commitment. In response to reduced SO2 emissions, atmospheric deposition of sulphate (SO4 2–) and SO4 2– concentrations in many lakes have declined, particularly in south-central Ontario and southern Québec. Sulphate deposition still exceeds aquatic critical loads throughout southeastern Canada however. Increasing pH or alkalinity (commonly deemed recovery) has been observed in only some lakes. Several biogeochemical factors have intervened to modify the lake chemistry response to reduced SO4 2– input, notably release of stored SO4 2– from wetlands following periods of drought and reduction in the export of base cations from terrestrial soils. Three examples from Ontario are presented to illustrate these responses. Significant increases in pH and alkalinity have been observed in many lakes in the Sudbury area of Ontario due to the large reductions in local SO2 emissions; early-stage biological recovery is evident in these lakes. An integrated assessment model predicts that AQA emission reductions will not be sufficient to promote widespread chemical or biological recovery of Canadian lakes. Monitoring and modeling are mutually supporting assessment activities and both must continue.  相似文献   
949.
陈旭 《干旱环境监测》2004,18(2):106-108
利用美国陆地资源卫星TM5遥感信息,调查分析了鞍山市森林资源现状。结果表明,鞍山市共有森林资源466933.52hm^2,占全市土地面积的50.32%,其中灌木林占森林面积的81.11%。在此基础上,分析了存在的主要问题,并提出了恢复途径及生态建设模式。  相似文献   
950.
目前新疆境内油田主要环境问题与对策   总被引:3,自引:0,他引:3  
根据实际调查资料,分析了目前新疆境内油田的主要环境问题,并结合我区实际,提出了对策建议。  相似文献   
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