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271.
We have conducted temperature-dependent studies on the removal of a solidified tarry residue from feathers using magnetic particles. These studies demonstrate an acute temperature dependency whereby no contaminant at all is removed below a certain temperature but, at and above this temperature, the removal rapidly approaches 100%. Significantly, this temperature is well below the temperature at which the tarry residue becomes a flowing liquid. This demonstrates that it is possible for magnetic cleansing to remove up to 100% of tarry residue from feathers under temperature conditions that would be benign to a bird.  相似文献   
272.
采用铁闪锌矿常压直接酸浸制取硫酸锌、研究了浸取条件对气体硫化物排放量的影响。试验结果表明:浸取时硫酸浓度为20%~40%(m),温度为120~140℃,液固比为(4:1)~(8:1)(m),通氧速度为35~50cm~3·(min.dm~3)~(-1),含硫气体排放量最低,常压酸浸2h,锌的一次浸取率达90%以上,闪锌矿中的硫绝大部分转化为单质硫。  相似文献   
273.
研究了以海绵铁对洗浴废水中阴离子洗涤剂十二烷基苯磺酸钠(LAS)的处理。静态实验结果表明,在铁锰比为6∶1、反应时间为60min时,海绵铁对洗浴废水中LAS的处理效率可达83%以上。动态实验结果表明,LAS含量为4.3mg/L的洗浴废水,以4L/h的流量经海绵铁柱处理后,LAS去除率可达94%以上。  相似文献   
274.
Bisphenol A (BPA) has received increasing attention due to its long-term industrial application and persistence in environmental pollution. Iron-based carbon catalyst activation of peroxymonosulfate (PMS) shows a good prospect for effective elimination of recalcitrant contaminants in water. Herein, considering the problem about the leaching of iron ions and the optimization of heteroatoms doping, the iron, nitrogen and sulfur co-doped tremella-like carbon catalyst (Fe-NS@C) was rationally designed using very little iron, S-C3N4 and low-cost chitosan (CS) via the impregnation-calcination method. The as-prepared Fe-NS@C exhibited excellent performance for complete removal of BPA (20 mg/L) by activating PMS with the high kinetic constant (1.492 min−1) in 15 min. Besides, the Fe-NS@C/PMS system not only possessed wide pH adaptation and high resistance to environmental interference, but also maintained an excellent degradation efficiency on different pollutants. Impressively, increased S-C3N4 doping amount modulated the contents of different N species in Fe-NS@C, and the catalytic activity of Fe-NS@C-1-x was visibly enhanced with increasing S-C3N4 contents, verifying pyridine N and Fe-Nx as main active sites in the system. Meanwhile, thiophene sulfur (C-S-C) as active sites played an auxiliary role. Furthermore, quenching experiment, EPR analysis and electrochemical test proved that surface-bound radicals (·OH and SO4⋅−) and non-radical pathways worked in the BPA degradation (the former played a dominant role). Finally, possible BPA degradation route were proposed. This work provided a promising way to synthesize the novel Fe, N and S co-doping carbon catalyst for degrading organic pollutants with low metal leaching and high catalytic ability.  相似文献   
275.
Nahar MS  Hasegawa K  Kagaya S 《Chemosphere》2006,65(11):1976-1982
Fe-doped TiO2 was prepared by the calcination of FexTiS2 (x = 0, 0.002, 0.005, 0.008, 0.01) and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV–visible diffuse reflectance spectra. All the Fe-doped TiO2 were composed of an anatase crystal form and showed red shifts to a longer wavelength. The activity of the Fe-doped TiO2 for the degradation of phenol was investigated by varying the iron content during UV (365 nm) and visible light (405 nm and 436 nm) irradiation. The degradation rate depended on the Fe content and the Fe-doped TiO2 was responsive to the visible light as well as the elevated activity toward UV light. The molar ratio of 0.005 was the optimum for both the UV and visible light irradiations. The result was discussed on the basis of the balance of the excited electron–hole trap by the doped Fe3+ and their charge recombination on the doped Fe3+ level. The Fe-doped TiO2 (x = 0.005) was more active than P25 TiO2 under solar light irradiation. The suspended Fe-doped TiO2 spontaneously precipitated once the stirring of the reaction mixture was terminated.  相似文献   
276.
The suitability of the primmorphs system as a good model for biotechnological applications led researchers on primmorphs to look for a medium to stimulate cell proliferation and therefore growth of aggregates. Recent efforts have focused on the use of Fe+3 and Si that, supplemented to cell culture medium, were found to be promising for growth and morphogenesis of the sponge Suberites domuncula. In this work, we analysed the effect of iron and dissolved silica on primmorphs of Petrosia ficiformis, by testing them at different concentrations in successive experiments. The purpose of these experiments was to test their effect on primmorphs and individuate their optimal concentration for this species. Our results suggest a negative effect of iron on primmorphs of P. ficiformis and a positive effect of silica on primmorphs size and spiculogenesis at a concentration of 120 μM.  相似文献   
277.
Pentachlorophenol (PCP) in contaminated soil was removed by treatment with aqueous solutions of iron(III)-porphyrin complexes as catalysts and potassium monopersulfate (KHSO5) as the oxygen donor. The contaminated soils were artificially prepared by spiking PCP to the kaolin and ando soils. Three types of iron(III)-porphyrin complexes, tetra(?p-sulfophenyl) porphineiron(III) (Fe(III)-TPPS), tetra(N-methyl-4-pyridil)porphineiron(III) (Fe(III)-TMPyP) and heme, were examined, and Fe(III)-TPPS was found to be the most effective for removing PCP. Although the sequential addition of KHSO5 was examined, in an attempt to improve the efficiency of PCP removal, it was not effective. In a preliminary test of various aqueous solutions, the addition of humic acid (HA), with a lower degree of humification, led to a significant enhancement in PCP removal. When HA was added to the soil system, the percentages of PCP removal were increased by up to 10% compared to the absence of HA. Therefore, the addition of HA to the catalytic system was useful in enhancing PCP removal from contaminated soil.  相似文献   
278.
Long-wall mining method has its own advantages, such as small mining-cutting ratio, the simple technique of recovery and high level of mechanization, which is the optimal method used to mine gently inclined and extremely thin iron mine. How to ensure the safety of workers and equipment during mining is the key technical process. Based on elastic-plastic mechanics theory, the mechanic model of long-wall method mining gently inclined and extremely thin iron mine is established and the critical safety distance of workface is obtained. With the FLAC-2D simulation software, the rule of stress change, the deformation of workface and surrounding rock in different control-roof width are also summarized. The final results accord with the ones of theory test. We confirm the support-frame resistance of workface by analogy-statistic method. The results prove that hydraulic support-frame have the ability to provide enough pressure to assure the stability of working face within the 5-m of control-roof width.  相似文献   
279.
Bentonite clay has been used for the adsorption of Fe(II) from aqueous solutions over a concentration range of 80-200 mg/l, shaking time of 1-60 min, adsorbent dosage from 0.02 to 2 g and pH of 3. The process of uptake follows both the Langmuir and Freundlich isotherm models and also the first-order kinetics. The maximum removal (>98%) was observed at pH of 3 with initial concentration of 100 mg/l and 0.5 g of bentonite. The efficiency of Fe(II) removal was also tested using wastewater from a galvanized pipe manufacturing industry. More than 90% of Fe(II) can be effectively removed from the wastewater by using 2.0 g of the bentonite. The effect of cations (i.e. zinc, manganese, lead, cadmium, nickel, cobalt, chromium and copper) on the removal of Fe(II) was studied in the concentration range of 10-500 mg/l. All the added cations reduced the adsorption of Fe(II) at high concentrations except Zn. Column studies have also been carried out using a certain concentration of wastewater. More than 99% recovery has been achieved by using 5 g of the bentonite with 3M nitric acid solution.  相似文献   
280.
本文基于情景分析理论和方法,建立了钢铁工业物质流与价值流协调度模型,对未来一段时期钢铁工业的协调发展状况进行研究.在维持现有发展模式的基准情景下,我国钢铁工业协调发展度将持续下降,2020年将下降到0.73.在环境恶化和经济效益相对脱钩的情景下,直到2020年我国钢铁工业协调发展度将维持在0.85的水平.而在经济与环境出现绝对脱钩的情景下,我国钢铁工业协调发展度将持续上升,2020年将达到0.95的高水平.因此,近期我国钢铁工业应遵循“基准相对脱钩绝对脱钩”的发展路径,降低总物质投入和污染物排放总量,提升经济产出效益,可持续发展才有可能实现.  相似文献   
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