全文获取类型
收费全文 | 3090篇 |
免费 | 378篇 |
国内免费 | 1447篇 |
专业分类
安全科学 | 282篇 |
废物处理 | 208篇 |
环保管理 | 376篇 |
综合类 | 2381篇 |
基础理论 | 443篇 |
污染及防治 | 710篇 |
评价与监测 | 85篇 |
社会与环境 | 110篇 |
灾害及防治 | 320篇 |
出版年
2024年 | 23篇 |
2023年 | 126篇 |
2022年 | 173篇 |
2021年 | 183篇 |
2020年 | 155篇 |
2019年 | 174篇 |
2018年 | 148篇 |
2017年 | 192篇 |
2016年 | 207篇 |
2015年 | 244篇 |
2014年 | 252篇 |
2013年 | 298篇 |
2012年 | 365篇 |
2011年 | 369篇 |
2010年 | 236篇 |
2009年 | 232篇 |
2008年 | 154篇 |
2007年 | 233篇 |
2006年 | 194篇 |
2005年 | 129篇 |
2004年 | 103篇 |
2003年 | 94篇 |
2002年 | 93篇 |
2001年 | 92篇 |
2000年 | 70篇 |
1999年 | 55篇 |
1998年 | 57篇 |
1997年 | 53篇 |
1996年 | 23篇 |
1995年 | 43篇 |
1994年 | 35篇 |
1993年 | 35篇 |
1992年 | 18篇 |
1991年 | 14篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1987年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有4915条查询结果,搜索用时 15 毫秒
261.
262.
超临界水氧化是一项对有机废液焚烧处理最有潜力的替代技术,在过去的20多年里,这项技术引起了广泛的关注。然而,作为一项管端技术,超临界水氧化仍存在许多不足,这些不足阻碍了它的工业应用。除了反应器腐蚀和盐析导致的技术问题外,超临界水氧化经常被认为是一项处理所有废液的“通用”技术,然而也是无法实现的“通用”技术。本文介绍了作为管端处理技术的超临界水氧化技术存在的问题,讨论了可能的解决办法,介绍了不同反应器的概念,提出了在超临界水氧化领域里开展进一步研究和发展新工艺流程的建议。此外,评价了超临界水氧化技术涉及到的自身能源供应问题。 相似文献
263.
264.
苏里格气田试气队伍节能减排工作现状及改进建议 总被引:1,自引:1,他引:0
苏里格气田试气队伍因涉及数家企业单位,节能减排工作有其特殊性和复杂性。通过调查试气过程中的排污状况,分析了其节能减排工作中出现的几个问题,如计量粗放、管理薄弱、措施简单等,提出了健全管理制度,完善计量系统,鼓励技术研究,加强自主创新,创建统一平台,依靠丙方监管等措施,以促进其节能减排工作健康有序地发展。 相似文献
265.
曙光油田节能减排现状调查及对策研究 总被引:1,自引:1,他引:0
曙光采油厂随着超稠油的不断开发,生产能耗也随之增加,通过开展节能减排及节能挖潜工作,全厂能耗增长状态得到了良好的控制,能耗总量由2005年的58.21×10~4t标煤下降到2008年的47.75×10~4t标煤;原油(气)液生产单位综合能耗为52.02 kg标煤/t,同期对比减少0.38 kg标煤/t;生产系统运行效率不断提高。文章详细介绍了曙光油田从机采系统、热注系统、集输系统等方面推广应用节能新技术、新产品,达到其投资和运行费用最少,经济性较好,对油田减排挖潜进行了探讨。 相似文献
266.
社会减灾能力信任及水灾风险感知的区域对比——基于江西九江和宜春公众的调查 总被引:2,自引:0,他引:2
研究公众对社会减灾能力及灾害风险的认识,有助于从公众视角揭示风险潜在因素,不仅是进行风险沟通的必备环节,还可以为开展有效的减灾宣传教育、提高公众减灾意识提供决策依据。通过社会调查(221份样本)和统计分析方法,比较了江西九江、宜春公众对于社会减灾能力的信任及水灾风险感知。结果表明,公众对于社会减灾能力基本持信任态度,信任度高低排序为:灾害监测预报>政府应急>防灾工程>预警传播,其中宜春公众的信任度较高;公众对于水灾的风险感知较弱,尤其是宜春公众认为水灾发生、受灾的可能性很小;公众的信任与对区域减灾能力的了解无关,主要是受到受灾经历(受灾次数、灾情损失、灾后救援)的影响,即区域本底灾害风险的高低导致公众认知的差异,风险较高区域(九江)的公众具有更为明确的降低风险的行为倾向及意愿。 相似文献
267.
Specific ecogenetic features of solods in the forest-steppe zone has been studied, and the role of biotic and abiotic factors of soil formation has been estimated. Differentiation of soil horizons with respect to the physical clay fraction accounts for specific features of their moistening, which is reflected in the ratio of strongly and weakly crystallized forms of iron. Periodic changes in redox conditions results in iron segregation, and a high content of fulvic acids accounts for its eluvial migration. These processes are controlled by soil geochemical barriers. 相似文献
268.
Degradation of pentachlorobiphenyl by a sequential treatment using Pd coated iron and an aerobic bacterium (H1) 总被引:1,自引:0,他引:1
The reductive dechlorination and biodegradation of 2,2′4,5,5′-pentachlorobiphenyl (PCB#101) was investigated in a laboratory-scale. Palladium coated iron (Pd/Fe) was used as a catalytic reductant for the chemical degradation of 2,2′4,5,5′-pentachlorobiphenyl, and an aerobic bacteria was used for biodegradation following the chemical reaction in this study. Dechlorination was affected by several factors such as Pd loading, initial soil pH and the amount of Pd/Fe used. The results showed that higher Pd loading, higher dosage of Pd/Fe and slightly acid condition were beneficial to the catalytic dechlorination of 2,2′,4,5,5′-pentachlorobiphenyl. In laboratory batch experiments, 2,2′4,5,5′-pentachlorobiphenyl was reduced in the presence of Pd/Fe bimetal, which was not further degraded by aerobic bacteria. 2,2′,4-trichlorobiphenyl (PCB#17), a reduction product from 2,2′4,5,5′-pentachlorobiphenyl, was readily biodegraded in the presence of a aerobic bacterial strain. It is suggested that an integrated Pd/Fe catalytic reduction-aerobic biodegradation process may be a feasible option for treating PCB-contaminated soil. 相似文献
269.
The goal of this paper is to find methodologies for removing a selection of impurities (H2O, O2, Ar, N2, SOx and NOx) from CO2 present in the flue gas of two oxy-combustion power plants fired with either natural gas (467 MW) or pulverized fuel (596 MW). The resulting purified stream, containing mainly CO2, is assumed to be stored in an aquifer or utilized for enhanced oil recovery (EOR) purposes. Focus has been given to power cycle efficiency i.e.: work and heat requirements for the purification process, CO2 purity and recovery factor (kg of CO2 that is sent to storage per kg of CO2 in the flue gas). Two different methodologies (here called Case I and Case II) for flue gas purification have been developed, both based on phase separation using simple flash units (Case I) or a distillation column (Case II). In both cases purified flue gas is liquefied and its pressure brought to 110 atm prior to storage.Case I: A simple flue gas separation takes place by means of two flash units integrated in the CO2 compression process. Heat in the process is removed by evaporating the purified liquid CO2 streams coming out from both flashes. Case I shows a good performance when dealing with flue gases with low concentration of impurities. CO2 fraction after purification is over 96% with a CO2 recovery factor of 96.2% for the NG-fired flue gas and 88.1% for the PF-fired flue gas. Impurities removal together with flue gas compression and liquefaction reduces power plant output of 4.8% for the NG-fired flue gas and 11.6% for the PF-fired flue gas. The total amount of work requirement per kg stored CO2 is 453 kJ for the NG-fired flue gas and 586 kJ for the PF-fired flue gas.Case II: Impurities are removed from the flue gas in a distillation column. Two refrigeration loops (ethane and propane) have been used in order to partially liquefy the flue gas and for heat removal from a partial condenser. Case II can remove higher amounts of impurities than Case I. CO2 purity prior to storage is over 99%; CO2 recovery factor is somewhat lower than in Case I: 95.4% for the NG-fired flue gas and 86.9% for the PF-fired flue gas, reduction in the power plant output is similar to Case I.Due to the lower CO2 recovery factor the total amount of work per kg stored CO2 is somewhat higher for Case II: 457 kJ for the NG-fired flue gas and 603 kJ for the PF-fired flue gas. 相似文献
270.
介绍了氧-乙炔火焰切割加工废钢铁产生的烟尘治理系统的设计和系统设备选型,重点介绍了烟尘捕集罩的设计和除尘器、电磁脉冲阀、风机的选型和PLC自动控制以及系统实际运行效果,为废钢铁加工企业治理污染提供一套简单、经济、实用的除尘系统作参考. 相似文献