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431.
H103大孔树脂吸附苯酚性能研究 总被引:2,自引:0,他引:2
通过静态吸附实验,研究了不同条件下H103大孔树脂对水中苯酚的吸附性能。结果表明,树脂对水中苯酚的吸附速率较快,60 min内基本达到平衡。树脂对水中苯酚的吸附量随其初始浓度的增加而增加,并呈线性关系。吸附数据采用Freundlich吸附等温线模型拟合结果较好。动态处理某精细化工含酚废水结果表明,室温下固定床流速为3 ... 相似文献
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针对不饱和聚酯树脂生产高浓度废水的特点,采用新型共沸精馏技术进行资源化预处理。实验结果表明,共沸精馏几乎将废水中的原料、聚合中间体等有机物全部浓缩于釜液中,釜底浓缩液COD可高达120万mg/L左右,有机物回收率达93%~96%。将COD约120万nq-g/L的釜液以20%比例投入不饱和聚酯树脂合成反应中,制得了一种新型高性能树脂,且树脂的得率由常规生产的93.4%提高至99.77%。对与共沸剂分离后的COD约为1万mg/L的馏出液采用新型多技术协同催化氧化技术进行预处理,使废水B/C由0.021提高至0.3以上;再采用EGSB+MBBR生化处理和活性炭吸附深度处理,出水可稳定达标排放,并能满足循环冷却水要求。 相似文献
434.
为寻求一种廉价高效的漆酶固定化方法,以树脂D380为载体、戊二醛为交联剂,结合吸附法和交联法固定真菌漆酶,并研究固定化漆酶的性质。最优固定化条件:1g载体在20mL0.7%的戊二醛溶液中交联2h后,加入2mL稀释酶液和5mLpH为4的醋酸一醋酸钠缓冲溶液,在25℃下吸附反应6h,最终获得的酶活回收率为65.94%。固定化漆酶的最适温度为20℃,最适pH为4,在4℃下保存14d仍保持约80%的酶活力。自由漆酶和固定化漆酶的Km值分别为1.207mmol/L和1.616mmol/L,说明固定后漆酶对底物的亲和力有所下降。 相似文献
435.
Kreangkrai Maneeintr Amr Henni Raphael O. Idem Paitoon Tontiwachwuthikul Andrew G.H. Wee 《Process Safety and Environmental Protection》2008,86(4):291
Densities, viscosities and refractive indices of 4-diethylamino-2-butanol + water mixtures were measured over the entire concentration range of 0–1 mole fraction and temperature range from 298.15 to 343.15 K. Excess molar volumes, viscosity deviations, and molar refraction changes were calculated from the measurement results and correlated as a function of the mole fractions. Various models were used for correlation with the measured data. Out of these, the Redlich–Kister equation was the most suitable model that correlated best with experimental data. The percent absolute deviations obtained with this model were 0.03% for density, 0.88% for viscosity and 0.009% for refractive index. 相似文献
436.
Jörg Müssig 《Journal of Polymers and the Environment》2008,16(2):94-102
Natural fibres offer an interesting alternative to petrochemical products. Reclaimed cotton is mainly used as a low cost fibre to “fill” composites used as interior parts in the automotive industry. Mechanical requirements of such composites are low and the potential of the cotton-fibre to reinforce plastics is not used adequately. This paper gives background information and discusses the use of the cotton fibres in composites compared to ramie fibres. In this study the fibre strength was tested with a Dia-Stron device, fineness was tested with Fibreshape. A roller card is well suited to process fibres to a multi layer web. Cotton and ramie fibres were embedded in epoxy resin and a bio-based resin PTP®. The composites were tested for impact and tensile properties. The results show that mechanical properties of the composites are strongly influenced by fibre properties. The data and results demonstrate the important role force-elongation characteristics of fibre play in optimising the properties of natural fibre composites. Cotton with its morphological and mechanical properties can play a more crucial role to optimise products with a view to improve the impact properties. 相似文献
437.
酚醛树脂废水的回收预处理 总被引:13,自引:0,他引:13
酚醛树脂生产废水含酚量和含醛量都较高,采用酸性缩聚法或碱性缩聚法处理,能大大降低酚和醛的含量,而且能回收到一定量的树脂. 相似文献
438.
A polyvinylidene fluoride-based membrane bearing the diethylenetriaminepentaacetic acid chelating group was employed to recover Cu(II) from the Cu(II)-ethylenediaminetetraacetic acid complex aqueous solution. Effects of Ca(II), Fe(II), and Fe(III) on Cu(II) uptake were investigated by static batch adsorption tests and dynamic adsorption filtration. Isotherms, kinetics, and breakthrough curves of Cu(II) uptakes in the presence of the three cations at concentrations of 1 mmol L?1 were elucidated. The three cations showed a positive effect on the Cu(II) uptake; the stimulative roles were in the order of Fe(III) > Fe(II) > Ca(II). They did not alter the adsorption behavior of the membrane; adsorption isotherms and kinetics could be described by Langmuir and Lagergren second-order models, and Cu(II) adsorption was a spontaneous and exothermic process. The presence of Ca(II), Fe(II), and Fe(III) increased the sorption capacity of the membrane stack by 1.3, 1.9, and 3 times. Breakthrough time and the exhaustion time of membrane stacks were also extended. 相似文献
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