全文获取类型
收费全文 | 1113篇 |
免费 | 122篇 |
国内免费 | 519篇 |
专业分类
安全科学 | 134篇 |
废物处理 | 86篇 |
环保管理 | 88篇 |
综合类 | 775篇 |
基础理论 | 185篇 |
污染及防治 | 317篇 |
评价与监测 | 53篇 |
社会与环境 | 46篇 |
灾害及防治 | 70篇 |
出版年
2024年 | 11篇 |
2023年 | 33篇 |
2022年 | 104篇 |
2021年 | 94篇 |
2020年 | 88篇 |
2019年 | 68篇 |
2018年 | 61篇 |
2017年 | 86篇 |
2016年 | 74篇 |
2015年 | 85篇 |
2014年 | 84篇 |
2013年 | 97篇 |
2012年 | 100篇 |
2011年 | 98篇 |
2010年 | 84篇 |
2009年 | 81篇 |
2008年 | 88篇 |
2007年 | 47篇 |
2006年 | 51篇 |
2005年 | 53篇 |
2004年 | 46篇 |
2003年 | 19篇 |
2002年 | 18篇 |
2001年 | 18篇 |
2000年 | 31篇 |
1999年 | 23篇 |
1998年 | 19篇 |
1997年 | 25篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 12篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 7篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 5篇 |
1985年 | 1篇 |
排序方式: 共有1754条查询结果,搜索用时 15 毫秒
191.
化学修饰电极在环境微量及痕量有机物分析中的应用 总被引:1,自引:0,他引:1
根据实验研究及国内外文献,从伏安及电位溶出分析,流动注射/液相色谱电化学检测,化学修饰电极生物传感器及化学修饰电极预富集—石墨炉原子吸收法联用等方面,重点综述了化学修饰电极在环境微量及痕量有机物分析中的应用。 相似文献
192.
DerivingfreshwaterqualitycriteriaofsulphocyanicsodiumfortheprotectionofaquaticlifeinChinaZhangTongDepartmentofEnvironmentalE... 相似文献
193.
194.
195.
氧化镁FGD脱硫过程的建模及其应用 总被引:8,自引:0,他引:8
氧化镁烟气脱硫是以氧化镁为脱硫反应剂的一种湿法烟气脱硫技术,目前国内外应用甚少,但开发前景广阔。以实验室小试为基础,从气液传质入手,利用双膜理论建立脱硫过程的数学模型,从而对中试脱硫效率进行预测并进行参数敏感性分析。结果表明,模型预测的脱硫效率与实际脱硫效率有很高的吻合度,其计算参数能反映出实际运行参数对脱硫效率的影响,对实际工况中操作条件的变更以及运行参数的调试有很高的指导意义。 相似文献
196.
The 16S rDNA-based molecular technique was applied to analyze the microbial community of autotrophic denitrification bacteria in a biofilm developed on the surface of sulfur particles and then the biochemistry process involved in this biofilm was discussed based on the microbial community analysis. Six key operational taxonomy units were identified, which were all unknown species belonging to a wide range of bacteria from four major subdivisions (alpha, beta, gamma and delta) of the kingdom Proteobacteria and from the kingdom Chlorobia (green sulfur bacteria). One species was chemoautotrophic and related to Thiobacillus denitrificans, two species were photoautotrophic, and three were chemoheterotrophic. Contrary to expectation, T. denitrificans-like bacteria constituted only 32% of the microbial community. As a result of the study, the entire microbiology of the autosulfurotrophic denitrification process as well as the interactions between the different microbial groups in the biofilm may need to be reconsidered. 相似文献
197.
Cu^2+沉淀-氧化法脱除H2S废气回收硫磺研究 总被引:2,自引:0,他引:2
开发了一种用含Cu^2+的溶液吸收H2S,并用Cu^2+自氧化CuS制取硫磺的新工艺,Cu^2+的还原产物CuCl2^-由空气氧化再生,实现循环。考察了Cu^2+浓度与净化效率的关系,研究了Cu^2+、H^+、助剂N的浓度和温度对Cu^2+氧化CuS效率的影响及H^+、助剂N的浓度、空塔气速和温度对Cu^2+空气氧化再生效率的影响。结果表明,该技术对H2S废气净化效率100%,Cu^2+氧化CuS及Cu^2+空气氧化再生条件温和、效果好,终产物硫磺纯度高。 相似文献
198.
Comparison of microbial community between two shallow freshwater lakes in middle Yangtze basin, East China 总被引:2,自引:0,他引:2
In order to investigate the role of the microbial community in aquatic ecology and nutrient transformations in the development of eutrophication in large shallow freshwater lakes along Yangtze River, the microbial community in the depth-related sediment in Lake Chaohu and Lake Longganhu were compared. Lake Chaohu is one of the three most polluted lakes in China. However, the neighboring Lake Longganhu, a mesotrophic lake, is relatively pristine. The total phosphorous (TP) and total nitrogen (TN) concentration in water was detected at 0.193 mgl(-1) and 3.035 mgl(-1) for Lake Chaohu, 0.051 mgl(-1) and 0.774 mgl(-1) for Lake Longganhu, respectively. The population of the microorganisms with various ecological nutrient transforming functions (e.g. phosphate solubilizing, denitrifying and cellulose decomposing) and a batch of environmental parameters concerning the nutrient accumulating and transforming (e.g. total organic carbon, total nitrogen, and total phosphorous concentrations) were assayed in the depth-related sediment samples from several defined points in both lakes. The sediment samples from Lake Chaohu showed higher density of actinomycetes (P<0.05) and phosphate-solubilizing bacteria (P<0.001) and less profusion of denitrifying bacteria (P<0.05) and cellulolytic microbes (P<0.001), compared with those of Lake Longganhu. The data suggested that the current microbial community in the sediment of Lake Chaohu is in favor of sustaining or further accelerating the process of the lake eutrophication. A possible positive feedback loop which consists of sustained growth of microorganisms and gradual decline of lake eutrophic status is worth further discussing. 相似文献
199.
Tong HY Hung WT Cheung CS 《Journal of the Air & Waste Management Association (1995)》2000,50(4):543-554
This paper reports on the analysis of on-road vehicle speed, emission, and fuel consumption data collected by four instrumented vehicles. Time-, distance-, and fuel-based average fuel consumption, as well as CO, HC, NOx, and soot emission factors, were derived. The influences of instantaneous vehicle speed on emissions and fuel consumption were studied. It was found that the fuel-based emission factors varied much less than the time- and distance-based emission factors as instantaneous speed changed. The trends are similar to the results obtained from laboratory tests. The low driving speed contributed to a significant portion of the total emissions over a trip. Furthermore, the on-road data were analyzed using the modal approach. The four standard driving modes are acceleration, cruising, deceleration, and idling. It was found that the transient driving modes (i.e., acceleration and deceleration) were more polluting than the steady-speed driving modes (i.e., cruising and idling) in terms of g/km and g/sec. These results indicated that the on-road emission measurement is feasible in deriving vehicle emissions and fuel consumption factors in urban driving conditions. 相似文献
200.
本文系统回顾了中国环境战略与政策的发展进程,总结了中国环境战略与政策的特点及变化特征,并进一步提出新时期中国环境保护战略与政策的推进方向。中国环境战略与政策与经济社会发展同步,主要分为探索起步阶段(1972—1983年)、初创建立阶段(1984—1991年)、框架完善阶段(1992—2002年)、提升发展阶段(2003—2012年)、改革突破阶段(2013年至今)五个阶段,而随着中国环境战略与政策的发展,环境战略理念与环境政策导向都发生了转变。文章指出,未来中国环境保护战略与政策要应对新情况、解决新问题,需着眼于满足人民群众美好生活的需求,重视推动制度重构和绿色转型,推动走上生态优先、绿色发展的新路,强化制度政策的内生动力,加强政策统筹协同。 相似文献