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991.
山苍籽油抗霉作用研究   总被引:4,自引:1,他引:4  
用减压蒸馏法从山苍籽[Litseacubeba(Lour)Per]提取天然植物精油.以熏蒸和喷洒等方式进行对档案资料、图书的防霉实验.结果表明山苍籽油具有显著的防霉功效,防霉的广谱性和高效性优于目前市售产品.该植物精油对纤维素和少量半纤维素、木质素纸张耐折度.抗老化及字迹颜色坚牢度试验.表明对纸张和字迹无显著影响;毒理分析表明属于安全低毒抗霉剂  相似文献   
992.
Bayesian hierarchical models were used to assess trends of harbor seals, Phoca vitulina richardsi, in Prince William Sound, Alaska, following the 1989 Exxon Valdez oil spill. Data consisted of 4–10 replicate observations per year at 25 sites over 10 years. We had multiple objectives, including estimating the effects of covariates on seal counts, and estimating trend and abundance, both per site and overall. We considered a Bayesian hierarchical model to meet our objectives. The model consists of a Poisson regression model for each site. For each observation the logarithm of the mean of the Poisson distribution was a linear model with the following factors: (1) intercept for each site and year, (2) time of year, (3) time of day, (4) time relative to low tide, and (5) tide height. The intercept for each site was then given a linear trend model for year. As part of the hierarchical model, parameters for each site were given a prior distribution to summarize overall effects. Results showed that at most sites, (1) trend is down; counts decreased yearly, (2) counts decrease throughout August, (3) counts decrease throughout the day, (4) counts are at a maximum very near to low tide, and (5) counts decrease as the height of the low tide increases; however, there was considerable variation among sites. To get overall trend we used a weighted average of the trend at each site, where the weights depended on the overall abundance of a site. Results indicate a 3.3% decrease per year over the time period.  相似文献   
993.
本文对鳗鱼油的利用价值和利用现状进行了评价和回顾,提出了烤鳗废油利用中亟需解决的几个技术问题,并对烤鳗废油利用的开发前景进行了展望。  相似文献   
994.
油气田含盐水淡化和污水除盐现状及发展   总被引:2,自引:0,他引:2  
依据资料调研和现场调查,从5个方面介绍了油气田含盐水的状况,包括油气田含盐水类型、特征、淡化及处理技术,国内外含盐水淡化技术研究现状及最新发展,我国油气田含盐水淡化研究的着眼点和宜采用的技术。强调在油气田范围内,开展含盐水淡化处理技术研究,从根本上解决水资源短缺和排水造成的损失已成为油气田开发建设中不可忽视的问题。  相似文献   
995.
现代分离技术在环境分析中的应用   总被引:1,自引:1,他引:1  
对样品进行预处理分离的主要目的是:①浓缩痕量污染物,降低最小检测浓度;②除去干扰物,提高测定的精确度和灵敏度;③通过化学衍生,提高被测物的灵敏度和选择性;④消除对分析系统有害的物质,使仪器保持良好稳定的运行状况。文章综合论述了固相萃取技术、固相微萃取技术、膜萃取技术、超临界流体萃取技术、毛细管电泳技术、加速溶剂萃取技术和微波萃取技术等现代分离技术在大庆油田环境分析中的应用现状以及分离技术的发展前景。  相似文献   
996.
聚合物驱采出水处理工艺研究   总被引:7,自引:0,他引:7  
聚合物驱油技术在大庆油田得到广泛应用,由于采出水粘度大、油珠粒径小,其处理难度大于油田常规水驱采出水。通过对聚合物驱采出水的特性分析,并在现场分别进行了以横向流除油器(串联DTH聚结器)和水力旋流器为主体的工艺试验。其工艺参数分别为:横向流除油器和DTH聚结除油器的处理量均为85 m3/h,有效停留时间为2.4 h。过滤器为石英砂、磁铁矿双层滤料,处理量为20 m3/h,过滤周期24 h,反冲洗时间为15 min,一次和二次过滤的滤速分别为12 m3/h和8 m3/h。试验结果表明:两种工艺均可代替现有的沉降过滤工艺处理聚合物驱采出水。  相似文献   
997.
黄河三角洲湿地保护和油田开发的协调发展   总被引:3,自引:0,他引:3  
黄河三角洲新生湿地生态系统是黄河强造陆运动和海岸系统蚀退相互作用的产物,在这里雨热同季,形成了天然或人工、长久或暂时的、流动或静止的湿地。黄河三角洲具有自然、经济和社会三大类18项功能。油气资源的开发对其自然因素、潜在因素和对社会经济价值都有一定的影响,我们在开采石油的同时一定要注意生态保护,加强绿化、污染物排放总量控制、采用先进的开采技术和建立湿地补偿制度。  相似文献   
998.
In this study, reused sunflower cooking oil was investigated for rancidity. Three student cafeterias at the University of Dodoma (UDOM) were used for this particular study. Oil samples were analyzed at the University of Dodoma laboratories. Results showed that all parameters were beyond permissible limits by WHO/FAO standards. Acid values ranged between 0.841 and 4.319 mg KOH/g oil, which is beyond the allowable limits by WHO/FAO (0.6 mg KOH/g oil). Peroxide values were found to be 19.5 mill eq O2/kg oil (minimum), and 62 mill eq O2/kg oil (maximum), which are both above the recommended limits by WHO/FAO (10 mill eq O2/kg oil). Iodine values were found to be from 102.87 to 48.26-g I2/100 g oil, and were all beyond the recommended limits by WHO/FAO, of between 118- and 141-g I2/100 g oil. The study has further revealed that the number of customers that are saved by the three cafeterias exceeds the capacity of the cafeterias. This study also found out that many students (almost 74%) are not aware on general knowledge about rancidity, including health effects of using rancid oils. It is therefore recommended to the national regulatory authorities to formulate strict regulations to guide and control oil rancidity.  相似文献   
999.
甲醇装置杂醇油的回收利用   总被引:2,自引:0,他引:2  
克拉玛依石化公司对年处理量为10000t的甲醇装置进行的现状分析表明,对其产生的杂醇油应进行回收和利用。在详细分析了我国杂醇油各种处理方法的基础上,提出利用MTBE装置的甲醇回收塔T203来回收杂醇油。该方案实施后,不仅回收并利用了精甲醇,而且减少了对环境的影响。若每年从300m3杂醇油中回收精甲醇约120t,按2000元/t市场价,产生经济效益约24万元,每年可节约经费近48万元,取得了良好的社会效益和经济效益。  相似文献   
1000.
As a result of the changes that occur during their use, used engine oils tend to differ in chemical and physical composition from a virgin oil. In general recycled oils have: much higher water and sediment levels than virgin oil; relatively higher concentrations of organic compounds (oxidation products); and relatively higher levels of metals such as Fe, Cd, Cr, Pb, etc. Therefore, the aim of this work was to investigate, assess and to observe, by means of the physical and the chemical properties of the oils, atomic absorption (AA), inductive couple plasma (ICP) and Fourier transform infrared (FTIR) analyses the extent of the differences occurring between the virgin and recycled oil. In important part of this work was also the development of analytical techniques based on the use of FTIR spectroscopy; in relation to the rapid analysis of lubricants; in particular for the differentiation of virgin and recycled oil. The results obtained were expected to be useful for differentiation purposes, providing information on whether the metal concentrations and oxidation products could be an appropriate feature for differentiating a particular oil sample from the others. This work is categorized into a two-step procedure. Firstly, an evaluation of a typical FTIR spectrum of an engine oil sample (mono- and multigrade) is presented. The broad feature centered at 1716 cm(-1) is due to the presence of carbonyl containing degradation products of oil. A band observed at 1732, 1169, 1154 and 1270 cm(-1) assigned to the polymethacrylate stretching vibrations, allows the determination of viscosity modifier and pour point depressant additives. The observed differences in the specific spectral bands (1732, 1169, 1154 and 1270 and 1716 cm(-1)) are investigated and discussed. Secondly, an analytical technique for the measurement of the levels of the wear metals is also applied.  相似文献   
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