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971.
断裂构造的分形研究及其地质应用 总被引:2,自引:0,他引:2
文章详细总结了断裂构造分形研究的理论基础及其在地质研究中的应用。断裂构造的分维值可以定量描述断裂分布的复杂性和构造演化的成熟度 ,它是断层数量、规模、发育程度、组合方式及动力学的综合体现。断裂的分形结构特征与流体流动、油气运移成藏和矿床的形成有着十分密切的关系 ,断裂的分维值越高 ,断裂连通性越好 ,越有利于流体流动汇聚和矿床的形成。此外 ,还可以从活动断裂的分形分析来研究断层的活动性及其与区域地壳稳定性 ,进行地震预测。文中总结了目前断裂分形研究中存在的一些问题和改进方法以及今后研究的主要方向 相似文献
972.
973.
研究铁轻稀土,铁锰轻稀土复合氧化物催化剂对苯的催化活性,发现铁锰轻稀土复合氧化物催化剂对苯具有较理想的完全氧化活性;同时还研究了稀土用量及添加微量贵金属钯对催化剂性能的影响,发现轻稀土有一个恰当的添加比例,另外还发现添加微量钯可提高催化剂的初活性。 相似文献
974.
含氟废水的粉煤灰吸附研究 总被引:27,自引:0,他引:27
采用热电厂库弃物粉煤灰为吸附剂,对氟离子浓度为100 ̄500mg/L含氟废水进行了除氟研究,并搪塞了除氟机理。结果表明,除氟性能与粉煤类的粒径大小,吸附时间,氟离子初始浓度,废水的PH值,温度等有关,粉煤灰-氟离子体系的吸附行为符合Langmuir吸附等温方程,氟离子在粉灰煤表面形成了氢键吸附和取代吸附。除氟率达90%以上,除氟后的饱和灰烧制成砖块,对环境不引起二次污染。 相似文献
975.
大型瑵HB对五氯苯酚的富集与释放动力学研究谭渝云,孙美娟(中国科学院水生生物研究所,武汉,430072)关键词大型;动力学;富集:释放;五氯苯酚.五氯苯酚(PCP)是一种应用十分广泛的杀虫剂和防腐剂,Detrick报道了世界上PCP每年施用量约为9×... 相似文献
976.
977.
凤眼莲净化含酚污水的研究——Ⅱ.组织、细胞和匀浆水平的试验 总被引:8,自引:0,他引:8
测定了凤眼莲根与叶组织、悬浮叶肉细胞以及根与叶组织匀浆对含酚污水的净化能力,结果表明,这些系统均具去除水中酚的明显作用,说明凤眼莲本身确有降解酚的效果。去除的酚是被组织或匀浆边吸收边降解的。用表面消毒杀死组织表面的微生物后,对叶的组织或匀浆除酚能力的影响很小,却使根组织的降酚过程明显减慢,证实了根际微生物在该系统起一定作用。黑暗条件下叶组织仍有降酚作用,只是速度比光照下稍减慢,说明光照在凤眼莲对酚水的净化中不是必需的。 相似文献
978.
Receptor models infer contributions from particulate matter (PM) source types using multivariate measurements of particle chemical and physical properties. Receptor models complement source models that estimate concentrations from emissions inventories and transport meteorology. Enrichment factor, chemical mass balance, multiple linear regression, eigenvector. edge detection, neural network, aerosol evolution, and aerosol equilibrium models have all been used to solve particulate air quality problems, and more than 500 citations of their theory and application document these uses. While elements, ions, and carbons were often used to apportion TSP, PM10, and PM2.5 among many source types, many of these components have been reduced in source emissions such that more complex measurements of carbon fractions, specific organic compounds, single particle characteristics, and isotopic abundances now need to be measured in source and receptor samples. Compliance monitoring networks are not usually designed to obtain data for the observables, locations, and time periods that allow receptor models to be applied. Measurements from existing networks can be used to form conceptual models that allow the needed monitoring network to be optimized. The framework for using receptor models to solve air quality problems consists of: (1) formulating a conceptual model; (2) identifying potential sources; (3) characterizing source emissions; (4) obtaining and analyzing ambient PM samples for major components and source markers; (5) confirming source types with multivariate receptor models; (6) quantifying source contributions with the chemical mass balance; (7) estimating profile changes and the limiting precursor gases for secondary aerosols; and (8) reconciling receptor modeling results with source models, emissions inventories, and receptor data analyses. 相似文献
979.
980.
Decomposition of simulated odors in municipal wastewater treatment plants by a wire-plate pulse corona reactor 总被引:1,自引:0,他引:1
Decomposition of simulated odors in municipal wastewater treatment plants was investigated experimentally by a wire-plate pulse corona reactor. A new type of high pulse voltage source with a thyratron switch and a Blumlein pulse forming network (BPFN) was adopted in our experiments, and the testing malodorants were ammonia, ethanethiol and tri-methyl amine, respectively. The maximum output power of the pulse voltage source and the maximum peak voltage were 1 kW and 100 kV. The experiments were conducted at the gas-flow rate of 4.0-23.0 m3 h(-1). Important parameters, including peak voltage, pulse frequency, capacitance (inductance) of the BPFN, gas-flow rate, initial concentration, which influenced on the removal efficiency, were investigated. The results show that the odors can be treated effectively. Almost 100% removal efficiency was obtained for 32 mg m(-3) ammonia at the gas-flow rate of 4.0 m(3) h(-1). The maximum removal efficiencies of 85 mg m(-3) ethanethiol and 750 mg m(-3) tri-methyl amine at 10.0 m(3) h(-1) were 98% and 91%, respectively. The energy yield of 110 mg m(-3) ammonia was 2.99 g kWh(-1) when specific energy density was 106 Jl(-1). In the cases of ammonia, ethanethiol and tri-methyl amine removal, ozone and nitrogen oxides were observed in the exit gas. The carbon and sulfur elements of ethanethiol and tri-methyl amine were mainly converted to carbon dioxide, carbon monoxide and sulfur dioxide. Moreover, the ammonium nitrates and sulfur were discovered in the reactor. 相似文献