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891.
离子交换树脂及其在废水处理中的应用 总被引:10,自引:0,他引:10
介绍了离子交换树脂及其在多种废水处理中的应用研究。离子交换树脂法处理废水具有可深度净化、处理效率高和能实现多种金属综合回收的优点,在水处理领域必将得到更为深入的应用。 相似文献
892.
利用前期实验筛选出的4株优势白腐真菌,处理阿维菌素废水经厌氧处理后的出水,实验结果表明,白腐真菌对该废水具有较好的处理效果,且其生长特性与处理效果基本正相关。 相似文献
893.
对印染废水治理的几点思考 总被引:6,自引:0,他引:6
结合轻工纺织化纤类环评工程师登记培训及日常工作中有关印染废水治理的一些经验和做法,分析探讨了目前印染废水处理工艺技术中存在的问题,诸如提高印染废水的可生化性、降低活性污泥的产量、以及碱减量、退浆废水局部预处理、色度去除的专项处理等问题,提出了可行的解决方案。 相似文献
894.
Using Biogeography to Help Set Priorities in Marine Conservation 总被引:4,自引:0,他引:4
895.
广西贵港市土地利用总体规划实施评价 总被引:15,自引:0,他引:15
目前沿用的土地利用总体规划实施评价的方法多为定性的直接描述法,缺乏科学的评价体系,难以对规划实施的效果作出客观、科学的评判。文章引入层次分析法(AHP),对贵港市土地利用总体规划实施效果进行量化研究。结果表明,虽然当地政府高度重视规划的实施,实施情况总体良好,但社会经济成效指标和完成性指标评价得分较低。建议该市今后加快“三农”政策的落实,以提高农民种粮的积极性和农民的收入水平;加大土地开发复垦、退耕还林资金投入,并制定有力的保障措施,促进完成性指标的实施。同时,提高社会意识度,是规划实施工作的重中之重,今后的规划要强化公众参与。 相似文献
896.
单甲脒在土壤中的吸附 总被引:20,自引:2,他引:20
用批量平衡法研究了单四脒酸盐的活性部分-单甲脒在不同类型土壤中的吸附行为,获得了单甲脒的单位土壤有机质吸附常数(Kom)为284和吸附自由能变化量为13.99kJ.mol^-1的实验数值,研究表明,单甲脒在土壤中吸附符合Freundlich经验公式,其在土壤中的吸附系数Kd与土壤中有机质含量和阳离了交换容量均显著正相关。 相似文献
897.
W. Ritchie 《Journal of Coastal Conservation》1995,1(1):63-76
Oil spill contingency plans are available for most coastlines but the amount of useful environmental data is variable. The
information should be held on a GIS base. High risk areas should be identified and the pre-existing store of environmental
knowledge should be commensurately extensive and should be available in considerable spatial detail. Contingency plans still
depend on basic lists of coastal types as defined by static, sediment based shoreline characteristics. There is a lack of
dynamic, process information. TheBraer oil spill of 1993 provides a case study of the application of sound coastal geomorphological and ecological data to impact
assessment. Monitoring of the ecological effects of this massive oil spill reinforces other research which indicates that
most coastlines can recover naturally from oil spills, and that oil spill clean up techniques may not necessarily benefit
rapid shoreline recovery. Although pre-existing environmental informations is important, the key decisions must be taken quickly
and are frequently judgmental and, therefore, place a premium on gathering appropriate scientific expertise to the site of
the spill as soon as possible and with sufficient powers to affect both the oil spill response, to initiate early surveys
of damage and to facilitate the initial monitoring programme. 相似文献
898.
Yorianta?Sasaerila Regine?Gries Gerhard?Gries Grigori?Khaskin Skip?King Stephen?Takács Hardi?) 《Chemoecology》2003,13(2):89-93
Summary. During peak calling activity by male oil palm bunch
moths, Tirathaba mundella Walker (Lepidoptera: Pyralidae), their
hairpencils, wings or entire body were extracted in hexane. Gas
chromatographic-electroantennographic detection (GC-EAD) analyses of
hair pencil extracts revealed four compounds that consistently elicited
responses from female antennae. The NMR spectrum of isolated compound 1,
and mass spectra and retention indices of compounds 1–4 suggested that
they were (3S,6S)-2,2,6-trimethyl-6-vinyl-tetrahydro-pyran-3-ol (1),
4-hydroxy-3-methoxy-benzaldehyde (2, vanillin),
6,10,14-trimethyl-2-pentadecanone (3), and
6,10,14-trimethyl-2-pentadecanol (4). Comparative GC and GC-MS analyses
of hair pencils extract and synthetic standards confirmed these
structural assignments. Moreover, comparative chromatography of
synthetic and hairpencil-isolated 1 on a Cyclodex-B column (which
separated the four stereoisomers with baseline resolution) revealed that
male T. mundella produce the SS-stereoisomer (SS-1). In field cage
bioassay experiments in Palembang, Indonesia, synthetic SS-1 and
vanillin in combination, but not singly, attracted female T. mundella.
SS-1 plus vanillin were as effective as male T. mundella in attracting
females. Compounds 3 and 4 did not enhance the blend's attractiveness.
Received October 11 2002; accepted March 14, 2003.
R1D="
Correspondence to: Gerhard Gries, email: gries@sfu.ca 相似文献
899.
臭氧氧化降解水溶液中1—萘酚的动力学研究 总被引:10,自引:0,他引:10
本文研究了水溶液中1-萘酚在鼓泡反应釜内臭氧氧化的消失动力学,考察了pH值、温度、自由基清除剂和1-萘酚的起始反应浓度等因素对反应的影响。结果表明,pH值、反应温度的提高有利于1-萘酚的降解。1-萘酚初始浓度低时其消失速率较高。该反应是有自由基反应贡献的分子臭氧氧化反应。在重碳酸盐存在下,1-萘酚的臭氧氧化降解符合一级反应动力学。 相似文献
900.
Abstract: Development of the Northwest Forest Plan (NWFP) was motivated by concerns about the overharvest of late-seral forests and the effects of intensive forest management on the long-term viability of the Northern Spotted Owl ( Strix occidentalis caurina ). Following several years of intense political and legal debates, the final NWFP was approved in 1994. Even though the plan evolved with a broad ecosystem perspective, it remained anchored in the Spotted Owl reserve design proposed in 1990. Based on a criterion of stable or increasing populations, a decade later it remains unclear whether the enactment of the NWFP has improved the conservation status of Spotted Owls. The results of intensive monitoring of several Spotted Owl populations for over a decade suggest a continuing range-wide decline even though rates of timber harvest have declined dramatically on federal lands. The cause of the decline is difficult to determine because the research needed to establish cause and effect relations has not been done. One plausible hypothesis is that the owl's life history greatly constrains its rate of population growth even when habitat is no longer limiting. Since enactment of the NWFP, new threats have arisen, including the movement of Barred Owls ( S. varia ) into the range of the Spotted Owl, political pressure to increase levels of timber harvest, and recent changes to forest laws that eliminate the requirement to assess the viability of wildlife populations on U.S. Department of Agriculture Forest Service lands. At this time is appears that Spotted Owl conservation rests critically on continued implementation of the protections afforded by the NWFP and the U.S. Endangered Species Act. 相似文献