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631.
632.
对钢铁厂铁鳞、铁红的基本物化性能和还原性能进行了研究。结果表明:粒度较粗、全铁较高铁鳞的还原性较好,适于作为优质海绵铁的原料。粒度极细、全铁高且杂质含量很低的铁红还原性也较好,适于作还原铁粉生产的原料。 相似文献
633.
钢渣处置工艺的清洁生产研究与实施 总被引:1,自引:0,他引:1
该课题研究了用水淬法和蒸汽法相结合的技术消除钢渣中的游离氧化钙;用传统的破碎磁选与高精度的强磁选相结合,以独创的递进除铁技术使钢渣中的含铁量由18%降至1%;用专项技术改制的管式磨、活化环,蒸汽熟化,递进式除铁,o-sepa选粉,高频振动粉磨,PPC集料器组成钢渣微粉清洁生产工艺.结果表明该工艺在国内尚属首例,具有较好的推广应用价值. 相似文献
634.
635.
Wang Hong liang Department of Biology Lanzhou University Lanzhou China Zhao Zhen jie Li Fa shen Department of Physics Lanzhou University Lanzhou China 《环境科学学报(英文版)》1998,(4)
1IntroductionAlthoughfiltermethodisverytimeconsuming,ithasbeenemployedintheinvestigationsofaerosolsforalongtime(Kopcewicz,19... 相似文献
636.
氨基染料生产过程中产生大量含有机物的铁泥,对环境造成严重污染并造成资源的极大浪费.利用超临界水氧化法对含有机物铁泥进行资源化处理研究,并对产物进行了X射线衍射分析(XRD)、色差实验与电子探针分析.研究结果显示,用超临界水氧化法处理铁泥可以将铁泥中所含的有机物完全氧化,真正实现环境友好;超临界水首先将铁泥氧化成α-Fe2O3与γ-Fe2O3,再经过800℃煅烧后可以作为氧化铁红颜料使用;超临界反应压力对样品的晶型与颜色影响不大. 相似文献
637.
Herpin U Siewers U Markert B Rosolen V Breulmann G Bernoux M 《Environmental science and pollution research international》2004,11(1):57-66
This paper shows the geographic distribution in Germany of iron (Fe), nickel (Ni) and lead (Pb) analyzed in mosses in 1995/96 and compares it with the results of the 1990/91 pilot study within a European moss-monitoring programme. Other elements (As, Cd, Cr, Cu, Ti, V, Zn) are compared on basis of the overall element medians for Germany of the 1990/91 and 1995/96 survey. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupressiforme and Hylocomium splendens were taken at a total of 1026 sites. In the 1995/96 monitoring campaign, 95% of the original sites of the 1990/91 study were resampled. The results from 1995/96 display local elevated values and many cases of areas affected by known sources of heavy-metal emissions. The industrialized and urban regions of Germany are shown up clearly by the 1995/96 moss-monitoring results: the Ruhr area, parts of Saarland and Baden-Württemberg, as well as areas in eastern Germany. Relatively low values for many elements were found in large areas of Lower Saxony and Bavaria. A comparison of the results of the 1990/91 and 1995/96 moss-monitoring programmes shows a fall in the concentration of the presented elements (except cadmium, copper and zinc) over the relevant period. Especially in the former GDR, chromium (Cr), iron (Fe), titanium (Ti) and vanadium (V) decreased significantly. This is, firstly, a reflection of the closure of and/or technological improvements to large power plants; secondly it is due to the fact that lignite has given way to other fuels. Vanadium (V) and nickel (Ni), typical constituents of crude oil, also show a decrease in the western part and thus document changes in the type of fuel consumed. The significant fall in lead concentration in 1995/96 as compared to 1990/91 in what used to be East and West Germany probably results from the increasing use of lead-free petrol. A comparison of the median values for 1990/91 and 1995/96 in mosses to the rate of emission of heavy metals in Germany for 1990 and 1995 shows similar trends in the case of elements such as arsenic (As), chromium (Cr), nickel (Ni), and lead (Pb). The comparison of the medians of the elements analyzed for 19 European countries indicates for most of the elements a general tendency to lower values in 1995, except for Lithuania, Netherlands, Portugal, Italy and United Kingdom. 相似文献
638.
为提高热轧工作区的雾化降尘效率,研究尘雾颗粒碰撞相关理论,以热轧产生的氧化铁皮粉尘为研究对象,建立基于雾滴粒径、雾滴速度和液体流量多个雾化参数的降尘效率计算模型;分析单一雾化参数对降尘效率的影响;通过实验,测得不同气液压力组合下的雾化参数,运用响应曲面法,分析多个雾化参数耦合对降尘效率的影响。结果表明:降尘效率随着雾滴粒径的减小、液体流量增大而提高,雾滴速度对其影响不明显;多因素耦合时,通过调节气液压力组合来控制降尘效率,结合高温环境对雾滴存活时间的影响分析,当气压0.3 MPa、液压0.5 MPa时,粒径为21~27 μm的粉尘沉降效果最佳,降尘效率达到90%以上,可有效解决热轧车间粉尘污染问题。 相似文献
639.
Huijing QIAN Yanjun WU Yong LIU Xinhua XU 《Frontiers of Environmental Science & Engineering in China》2008,2(1):51-56
The kinetics of Cr(VI) reduction to Cr(III) by metallic iron (Fe0) was studied in batch reactors for a range of reactant concentrations, pH and temperatures. Nearly 86.8% removal efficiency
for Cr(VI) was achieved when Fe0 concentration was 6 g/L (using commercial iron powder (< 200 mesh) in 120 min). The reduction of hexavalent chromium took
place on the surface of the iron particles following pseudo-first order kinetics. The rate of Cr(VI) reduction increased with
increasing Fe0 addition and temperature but inversely with initial pH. The pseudo-first-order rate coefficients (k
obs) were determined as 0.0024, 0.010, 0.0268 and 0.062 8 min−1 when iron powder dosages were 2, 6, 10 and 14 g/L at 25°C and pH 5.5, respectively. According to the Arrehenius equation,
the apparent activation energy of 26.5 kJ/mol and pre-exponential factor of 3 330 min−1 were obtained at the temperature range of 288–308 K. Different Fe0 types were compared in this study. The reactivity was in the order starch-stabilized Fe0 nanoparticles > Fe0 nanoparticles > Fe0 powder > Fe0 filings. Electrochemical analysis of the reaction process showed that Cr(III) and Fe(III) hydroxides should be the dominant
final products. 相似文献
640.
ZVI固定床-SBR耦合工艺强化氯代硝基苯的降解 总被引:4,自引:0,他引:4
研究了零价铁(ZVI)固定床-序批式生物反应器(SBR)耦合工艺对2-氯硝基苯(2-CINB)转化与降解强化作用.结果表明,ZVI固定床可稳 定还原转化2-CINB为2-氯苯胺(2-CIAn),表面积归一化速率常数(Ksa)为(3.20±0.35)×10-2L·m-2·h-1;ZVI固定床出水作为SBR进水,在HRT为20 h、2-ClAn负荷为3.6~111.8 g·m-3·d-1、COD负荷(外加碳源)为130.9~854.4 g·m-3 d-1条件下稳定运行SBR,其2-ClAn去除率 达99.9%以上,COD去除率达92.3%±5.5%.2-ClAn污泥比降解速率达0.31 g·g-1·d-1;耦合系统在不添加其它碳源、氮源条件下,TOC去除率达95.4%,总氮去除率为46.1%.而以未经ZVI预处理的2-CINB为进水的SBR对照实验发现,2-ClNB去除率仅为25.3%±10.2%.主要以挥发形式去除.研究结果揭示,ZVI-SBR耦合工艺可强化氯代硝基苯类污染物的降解与矿化. 相似文献