全文获取类型
收费全文 | 737篇 |
免费 | 62篇 |
国内免费 | 161篇 |
专业分类
安全科学 | 58篇 |
废物处理 | 52篇 |
环保管理 | 178篇 |
综合类 | 448篇 |
基础理论 | 54篇 |
污染及防治 | 107篇 |
评价与监测 | 39篇 |
社会与环境 | 22篇 |
灾害及防治 | 2篇 |
出版年
2024年 | 5篇 |
2023年 | 3篇 |
2022年 | 11篇 |
2021年 | 12篇 |
2020年 | 13篇 |
2019年 | 15篇 |
2018年 | 12篇 |
2017年 | 22篇 |
2016年 | 35篇 |
2015年 | 31篇 |
2014年 | 56篇 |
2013年 | 74篇 |
2012年 | 56篇 |
2011年 | 37篇 |
2010年 | 50篇 |
2009年 | 66篇 |
2008年 | 43篇 |
2007年 | 68篇 |
2006年 | 69篇 |
2005年 | 47篇 |
2004年 | 40篇 |
2003年 | 42篇 |
2002年 | 26篇 |
2001年 | 19篇 |
2000年 | 16篇 |
1999年 | 17篇 |
1998年 | 20篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1976年 | 1篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有960条查询结果,搜索用时 359 毫秒
791.
红外热像仪在电子设备热设计检查中的应用 总被引:1,自引:0,他引:1
在电子设备的研制和设计阶段,热测试与分析是热设计中的重要环节。本文阐述了利用红外热像仪对电子设备关键部位进行热测试,检测电子设备内部温度分布情况,并与设计目标进行比较与纠正,从而达到热设计的最终目的。 相似文献
792.
论郊区农业生态环境建设的几个问题 总被引:1,自引:0,他引:1
叶岱夫 《生态与农村环境学报》2001,17(1):60-63
在对郊区环境组成、结构、生态环境特征等区域研究的基础上 ,以边缘效应的理论为出发点 ,深入分析了城乡交错带的几个生态环境建设问题。认为郊区生态建设应以 (1)城市废弃物的再生地 ,(2 )生态旅游与农业文化的消费地 ,(3)现代持续农业的先导区等为目标。最后分析了城乡交错面 (边缘界面 )对城乡复合生态系统中环境应力的聚合放大效应 ,指出效区农业生态环境的调控是防止城乡矛盾激化的根本措施 相似文献
793.
Zanichelli D Carloni F Hasanaji E D'Andrea N Filippini A Setti L 《Environmental science and pollution research international》2007,14(1):5-6
Background, Aim and Scope
Agricultural industrial wastes can frequently be used as raw materials in the production of bio-fuels. Olive-oil milling wastewater
is considered as one of the most polluting agro-industrial residues, but fortunately due to its high content of organic matter,
it has the potential to be a valuable starting material to obtain bio-ethanol via fermentation with Saccharomyces cerevisiae.
The fermentation of olive-oil milling wastewater has been demonstrated with good yield of ethanol (8-12%v/v) once the level
of reducing sugars is appropriate and the phenolic fraction, which inhibits the yeast, is removed.
Materials and Methods:
-
Results:
-
Discussion:
-
Conclusions:
-
Recommendations and Perspectives:
- 相似文献
794.
Takashi Yamamoto Akiko Kida Yukio Noma Atsushi Terazono Shin-ichi Sakai 《Waste management (New York, N.Y.)》2014,34(2):536-541
Appropriate treatment of asbestos-containing wastes is a significant problem. In Japan, the inertization of asbestos-containing wastes based on new treatment processes approved by the Minister of the Environment is promoted. A highly sensitive method for testing asbestos fibers in inertized materials is required so that these processes can be approved. We developed a method in which fibers from milled treated materials are extracted in water by shaking, and are counted and identified by transmission electron microscopy. Evaluation of this method by using asbestos standards and simulated slag samples confirmed that the quantitation limits are a few million fibers per gram and a few μg/g in a sample of 50 mg per filter. We used this method to assay asbestos fibers in slag samples produced by high-temperature melting of asbestos-containing wastes. Fiber concentrations were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10?6 f/g. Because the evaluation of treated materials by TEM is difficult owing to the limited amount of sample observable, this testing method should be used in conjunction with bulk analytical methods for sure evaluation of treated materials. 相似文献
795.
Christos Aristeides Tsiliyannis 《Waste management (New York, N.Y.)》2013,33(9):1800-1824
Hazardous waste incinerators (HWIs) differ substantially from thermal power facilities, since instead of maximizing energy production with the minimum amount of fuel, they aim at maximizing throughput. Variations in quantity or composition of received waste loads may significantly diminish HWI throughput (the decisive profit factor), from its nominal design value. A novel formulation of combustion balance is presented, based on linear operators, which isolates the wastefeed vector from the invariant combustion stoichiometry kernel. Explicit expressions for the throughput are obtained, in terms of incinerator temperature, fluegas heat recuperation ratio and design parameters, for an arbitrary number of wastes, based on fundamental principles (mass and enthalpy balances). The impact of waste variations, of recuperation ratio and of furnace temperature is explicitly determined. It is shown that in the presence of waste uncertainty, the throughput may be a decreasing or increasing function of incinerator temperature and recuperation ratio, depending on the sign of a dimensionless parameter related only to the uncertain wastes. The dimensionless parameter is proposed as a sharp a’ priori waste ‘fingerprint’, determining the necessary increase or decrease of manipulated variables (recuperation ratio, excess air, auxiliary fuel feed rate, auxiliary air flow) in order to balance the HWI and maximize throughput under uncertainty in received wastes. A 10-step procedure is proposed for direct application subject to process capacity constraints. The results may be useful for efficient HWI operation and for preparing hazardous waste blends. 相似文献
796.
Jinxiu Huang Mengjun Chen Haiyan Chen Shu Chen Quan Sun 《Waste management (New York, N.Y.)》2014,34(2):483-488
In this work, a Brønsted acidic ionic liquid, 1-butyl-3-methyl-imidazolium hydrogen sulfate ([bmim]HSO4), was used to leach copper from waste printed circuit boards (WPCBs, mounted with electronic components) for the first time, and the leaching behavior of copper was discussed in detail. The results showed that after the pre-treatment, the metal distributions were different with the particle size: Cu, Zn and Al increased with the increasing particle size; while Ni, Sn and Pb were in the contrary. And the particle size has significant influence on copper leaching rate. Copper leaching rate was higher than 99%, almost 100%, when 1 g WPCBs powder was leached under the optimum conditions: particle size of 0.1–0.25 mm, 25 mL 80% (v/v) ionic liquid, 10 mL 30% hydrogen peroxide, solid/liquid ratio of 1/25, 70 °C and 2 h. Copper leaching by [bmim]HSO4 can be modeled with the shrinking core model, controlled by diffusion through a solid product layer, and the kinetic apparent activation energy has been calculated to be 25.36 kJ/mol. 相似文献
797.
The world’s waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite before the reutilization of the cathode ray tube (CRT) funnel glass, and the recycling of liquid crystal display (LCD) glass is economically viable for the containing of precious metals (indium and tin). However, the environmental assessment of the recycling process is essential and important before the industrialized production stage. For example, noise and dust should be evaluated during the glass cutting process. This study could contribute significantly to understanding the recycling methods of NMFs from WEEE and serve as guidance for the future technology research and development. 相似文献
798.
Significant quantities of wastes are generated as the waste materials or byproducts every day from stainless steel processes. According to the origins and characteristics, the stainless steel wastes can be mainly classified into two categories, slags and dusts. They usually contained considerable quantities of valuable metals and materials. This paper summarized and analyzed the generation, composition, characteristics and the leaching behaviors of the most of wastes obtained from the stainless steel processes. On this basis, a review of several methods for treating the various stainless steel wastes was made. It is very essential not only for recycling the valuable metals and mineral resources but also for protecting the environment. 相似文献
799.
800.
对缸内直喷汽油发动机上装用的电子装备振动环境试验标准化过程和要点作了介绍.也列举了一些验证中可能产生影响的因素.供产品标准制修订和实验室在设计试验时参考. 相似文献