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111.
采用己内酰胺-四丁基溴化铵为原料,按摩尔配比为2∶1配制成[CPL][TBAB]类离子液体,制备的离子液体与乙醇溶液按体积比为1.5∶1混合以降低其粘度,利用筛板塔进行吸收实验,考察最佳吸收条件及最大吸收效率。结果表明,在实验条件下,最大的吸收效率条件为:离子液体的流量为60 L/h,SO2的流量为0.2 L/min,SO2为30℃,最大吸收效率为47.6%。  相似文献   
112.
根据1988年全国农业环境质量状况调查资料,选取我国部分商品粮基地县土壤重金属污染数据(污染指数),通过多元统计分析,揭示了各商品粮基地土壤重金属污染的差异与分类.建立模糊综合评判模型对各商品粮基地土壤污染状况进行了综合评价,得到了各商品粮基地土壤污染程度的相对排序.   相似文献   
113.
根据爆炸焊接的装药特点,对爆炸焊接炸药的使用、爆炸产生的地震波、毒气、噪音等的安全性进行了分析,给出了定量的计算公式,同时还针对不同的爆破危害,提出了相应的安全防护措施  相似文献   
114.
The performance of UV/H2O2, UV/O3 and UV/H2O2/O3 oxidation systems for treating spent caustic from an ethylene plant was investigated, in UV/H2O2 system, with the increase of H202 dosage, removal efficiencies of COD and the ratio of biochemical oxygen demand(BOD) to chemical oxygen demand(COD) of the effluent were increased and a better performance was obtained than the H2O2 system alone. In UV/H2O2 system, removal efficiency of COD reach 68% under the optimum condition, and BOD/COD ratio was significantly increased from 0.22 to 0.52. In UV/O3 system, with the increase of O3 dosage, removal efficiency of COD and BOD/COD ratio were increased, and a better performance was obtained than the O3 system alone. Under the optimum condition, removal efficiency of COD was 54%, and BOD/COD ratio was significantly increased from 0.22 to 0.48. In UV/H2O2/O3 system, COD removal efficiency was found to be 22.0% higher than UV/O3 system.  相似文献   
115.
企业安全文化在安全管理中的创新实践   总被引:1,自引:0,他引:1  
杨鲁明  段成刚 《安全》2010,31(4):24-26
辽河油田公司作为油气生产、集输和销售企业,具有高风险的行业特点,始终面临着严峻的安全生产形势。因此,在加强安全管理的同时,积极推进企业安全文化建设,不断提高企业的整体安全素质,对于增强员工安全防范意识,减少安全生产事故,实现企业安全发展具有十分重要的意义。  相似文献   
116.
氢指数(HI)是重要的有机质评价参数,能够反映沉积有机质中脂肪大分子物质的相对含量,并用于反演水生生态系统的历史初级生产力,有助于研究藻类生产力对污染物的富集作用。为了探讨氢指数的环境指示作用,选择了亚热带的3座水库作为研究对象,采用Rock-Eval热解与生物标志物-中性糖方法相结合的研究技术,研究了沉积钻孔有机质的来源与特征;并结合210Pb和137Cs定年技术,综合运用氢指数和总糖含量对水库的初级生产力进行了重建。结果表明:中富营养的增塘和联安水库沉积有机质主要来源于浮游藻类,且受降解的程度较小,而贫营养的新丰江水库钻孔下层有机质主要是受降解作用或陆源高等植物等的影响。近年来,3个水库的HI值都有显著性的增加,且与其对应的总糖含量以及近50年来的滑动平均温度都高度的相关,说明这些水库都经历了气候变暖所引起的初级生产力增长。同时,升高的水库生产力扩大了沉积物剖面中重金属和多环芳烃的累积。  相似文献   
117.
研究条斑紫菜中磷和钙的亚细胞分布,并探讨其与条斑紫菜富集砷的关系。结果表明:条斑紫菜吸收磷、钙主要分布在细胞壁组分中,平均占总磷含量的53.9%,占总钙含量的61.25%,其次为细胞液。与对照组相比(砷暴露浓度0.5 mg·L~(-1)),在添加磷浓度为0.1 mg·L~(-1)和1.0 mg·L~(-1)处理组中,条斑紫菜中磷、砷之间呈现协同效应;当添加磷浓度为5.0 mg·L~(-1)和10.0 mg·L~(-1)时,条斑紫菜中磷、砷之间则呈现拮抗作用,砷的富集量分别比照组下降61.37%和72.73%。经添加钙液暴露过的条斑紫菜,当钙暴露浓度为1 000 mg·L~(-1)时其对砷的富集量比对照组减少15.51%。可知,5.0 mg·L~(-1)磷处理条斑紫菜,条斑紫菜对砷的富集受到明显的抑制。  相似文献   
118.
Direct individual analysis using Scanning Electron Microscopy combined with online observation was conducted to examine the S-rich particles in PM2.5 of two typical polluted haze episodes in summer and winter from 2014 to 2015 in Beijing. Four major types of S-rich particles, including secondary CaSO4 particles (mainly observed in summer), S-rich mineral particles (SRM), S-rich water droplets (SRW) and (C, O, S)-rich particles (COS) were identified.We found the different typical morphologies and element distributions of S-rich particles and considered that (C, O, S)-rich particles had two major mixing states in different seasons. On the basis of the S-rich particles’ relative abundances, S concentrations and their relationships with PM2.5 as well as the seasonal comparison, we revealed that the S-participated formation degrees of SRM and SRW would enhance with increasing PM2.5 concentration. Moreover, C-rich matter and sulfate had seasonally different but significant impacts on the formation of COS.
  相似文献   
119.
Polycyclic aromatic hydrocarbons (PAHs) are complex organic compounds which are identified as significant carcinogenic to human health. PAHs (mainly in particle phase) are susceptible to atmospheric oxidant gases, especially ozone, nitrogen oxides (NOx), hydroxyl radical (OH), and could be degraded on filters during sampling process, leading to an underestimation of ambient PAH concentrations. The goal of this work was to investigate particle associated PAHs sampling artifacts caused by ozone in summer of Beijing. Comparative sampling systems were operated simultaneously during the whole campaign, one with activated carbon ozone denuder, the other being set as conventional sampling system. Activated carbon denuder was testified to be highly efficient to eliminate ozone from air stream. In general, nine particle-bound PAHs observed from conventional sampler were all lower than those from ozone denuder system. The total PAHs (particle phase) concentration was averagely underestimated by 35.9% in conventional sampling procedure. Benzo[a]pyrene (BaP) had the highest percentage of mass loss. founded to have influences Ambient temperature was on PAHs sampling artifacts. High temperature can increase loss of particle associated PAHs during sampling.  相似文献   
120.
Mechanical waste-processing methods, which combine crushing and separation processes for the recovery of valuable materials, have been widely applied in waste printed wiring board (PWB) treatment. However, both the high impact toughness and the tensile and flexural strengths of whole PWB with a laminated structure result in great energy consumption and severe abrasion of the cutters during multi-level crushing. In addition, the high temperatures occurring in continual crushing probably cause the decomposition of the polymer matrix. A thermal-crack method using residual steam as the heating medium has been developed to pre-treat waste PWBs. This treatment reduces the mechanical strength in order to improve the recovery rate of valuable materials in subsequent mechanical recycling. The changes of the PWBs’ macro-mechanical properties were studied to evaluate thermal expansion impacts associated with changes in temperature, and the dynamic dislocation micro-structures were observed to identify the fracture mechanism. The results showed that thermal cracking with steam at the temperature of 500 K can effectively attenuate the mechanical properties of waste PWBs, by reducing the impact, tensile and flexural strengths respectively, by 59.2%, 49.3% and 51.4%, compared to untreated PWB. Thermal expansion can also facilitate the separation of copper from glass fiber by reducing peel resistance by 95.4% at 500 K. It was revealed that the flexural fracture was a transverse cracking caused by concentrated stress when the heating temperature was less than 500 K, and shifted to a vertical cracking after exceeding 500 K.  相似文献   
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