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481.
甾萜烷和多环芳烃在风化溢油鉴别中的应用研究 总被引:2,自引:0,他引:2
对母质来源、沉积环境和成熟度各异的原油样品进行风化模拟实验,并对实验产物进行GC-MS分析,最后对甾烷、萜烷和多环芳烃进行风化溢油鉴定的可行性、原理、常用指标等进行探讨。结果表明,不同油中同一甾烷、萜烷和芳烃生物标志化合物比值参数量值间有显著性差异;对相同油的风化和未风化样品而言,同一萜烷和甾烷比值参数的变异系数通常小于15%;同一烷基化多环芳烃的特征比值参数变异系数为6.51%~17.68%,而成熟度指标变异系数通常小于8%。甾萜烷和多环芳烃可以作为风化溢油鉴别的有效指标。 相似文献
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484.
Electrochemical dechlorination of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature. Palladium/foam-nickel (Pd/foam-Ni) and palladium/polymeric pyrrole film/foam-nickel (Pd/PPy/foam-Ni) composite electrodes which provided catalytic surface for reductive dechlorination of chloroform in aqueous solution were prepared using an electrodepositing method. Scanning electron microscope (SEM) micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode. The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 min, which is much higher than that of Pd/foam-Ni electrode. 相似文献
485.
Sulfur hexafluoride (SF6) is known as one of the most powerful greenhouse gases in the atmosphere. Reductive photodegradation of SF6 by styrene has been studied with the purpose of developing a novel remediation for sulfur hexafluoride pollution. Effects of reaction conditions on the destruction and removal efficiency (DRE) of SF6 are examined in this study. Both initial styrene-to-SF6 ratio and initial oxygen concentration exert a significant influence on DRE. SF6 removal efficiency reaches a maximum value at the initial styrene-to-SF6 ratio of 0.2. It is found that DRE increases with oxygen concentration over the range of 0 to 0.09 mol/m^3 and then decreases with increasing oxygen concentration. When water vapor is fed into the gas mixture, DRE is slightly enhanced over the whole studied time scale. The X-ray Photoelectron Spectroscopy (XPS) analysis, together with gas chromatography-mass spectrometry (GC-MS) and Fourier Transform Infrared spectroscopy (FT-IR) analysis, prove that nearly all the initial fluorine residing in the gas phase is in the form of SiF4, whereas, the initial sulfur is deposited in the form of elemental sulfur, after photodegradation. Free from toxic byproducts, photodegradation in the presence of styrene may serve as a promising technique for SF6 abatement. 相似文献
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考察了有机物甲醛、甲醇、甲酸和邻苯二甲酸二丁酯对单独臭氧氧化和蜂窝陶瓷催化臭氧化工艺去除水中硝基苯降解效果的影响规律.单独臭氧氧化和蜂窝陶瓷催化臭氧化对硝基苯的去除率随着甲醛浓度的升高(0~12 mg·L-1)分别降低了11.6%和9.6%;2种工艺对硝基苯的去除率都随着甲醇浓度的增加(0~16mg·L-1,)先增高再降低,单独臭氧氧化和蜂窝陶瓷催化臭氧化分别在浓度为2 mg·L-1和4 mg·L-1时去除率达到最大值;随着甲酸浓度的增加(0~8 mg·L-1)去除率也都先增高再降低,单独臭氧氧化和蜂窝陶瓷催化臭氧化分别在浓度为0.5 mg·L-1和2 mg·L-1时去除率达到最大值;低浓度的甲醇和甲酸促进了硝基苯的降解,高浓度的甲醇和甲酸抑制了硝基苯的降解.单独臭氧氧化和蜂窝陶瓷催化臭氧化在邻苯二甲酸二丁酯浓度增加(0~10 mg·L-1)的情况下对硝基苯的去除率分别降低了19.7%和18.6%. 相似文献
489.
通过静态实验对粘性土、450℃高温焙烧膨润土和双阳离子有机膨润土吸附垃圾渗滤液中污染物的能力进行对比,并以新鲜垃圾渗滤液为对象,对粘性土/450℃高温焙烧膨润土双层防渗层和黏性土/双阳离子有机膨润土双层防渗层的防渗性能和截污能力进行研究.结果显示,黏性土、450℃高温焙烧膨润土和双阳离子有机膨润土对垃圾渗滤液中污染物的吸附平衡时间均为24 h; 450℃高温焙烧膨润土和双阳离子有机膨润土对垃圾渗滤液中COD和NH+4的吸附作用均大于黏性土.同时, 2种双层防渗层的渗透系数分别能达到1.31×10-8 cm·s-1和2.80×10-8 cm·s-1;黏性土/450℃高温焙烧膨润土双层防渗层对于NH+4有较强的吸附能力,而黏性土/双阳离子有机膨润土双层防渗层对有机污染物质有很强的吸附能力,对COD的衰减率比前者高出33.82%.故针对垃圾填埋场不同污染物类型的差异可以选择不同改性膨润土作为反应型材料构建双层防渗层模式. 相似文献
490.
Electrochemical incineration of dimethyl phthalate by anodic oxidation with
boron-doped diamond electrode 总被引:1,自引:0,他引:1
The anodic oxidation of aqueous solutions containing dimethyl phthalate (DMP) up to 125 mg/L with sodium sulfate (Na2SO4) as
supporting electrolyte within the pH range 2.0–10.0 was studied using a one-compartment batch reactor employing a boron-doped
diamond (BDD) as anode. Electrolyses were carried out at constant current density (1.5–4.5 mA/cm2). Complete mineralization was
always achieved owing to the great concentration of hydroxyl radical (.OH) generated at the BDD surface. The e ects of pH, apparent
current density and initial DMP concentration on the degradation rate of DMP, the specific charge required for its total mineralization
and mineralization current e ciency were investigated systematically. The mineralization rate of DMP was found to be pH-independent
and to increase with increasing applied current density. Results indicated that this electrochemical process was subjected, at least
partially, to the mass transfer of organics onto the BDD surface. Kinetic analysis of the temporal change of DMP concentration during
electrolysis determined by High Performance Liquid Chromatography (HPLC) revealed that DMP decay under all tested conditions
followed a pseudo first-order reaction. Aromatic intermediates and generated carboxylic acids were identified by Gas Chromatography-
Mass Spectrometry (GC-MS) and a general pathway for the electrochemical incineration of DMP on BDD was proposed. 相似文献