全文获取类型
收费全文 | 388篇 |
免费 | 37篇 |
国内免费 | 85篇 |
专业分类
安全科学 | 54篇 |
废物处理 | 45篇 |
环保管理 | 50篇 |
综合类 | 211篇 |
基础理论 | 20篇 |
污染及防治 | 83篇 |
评价与监测 | 43篇 |
社会与环境 | 2篇 |
灾害及防治 | 2篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 10篇 |
2021年 | 12篇 |
2020年 | 10篇 |
2019年 | 11篇 |
2018年 | 8篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 19篇 |
2014年 | 39篇 |
2013年 | 41篇 |
2012年 | 39篇 |
2011年 | 31篇 |
2010年 | 25篇 |
2009年 | 38篇 |
2008年 | 26篇 |
2007年 | 29篇 |
2006年 | 35篇 |
2005年 | 25篇 |
2004年 | 13篇 |
2003年 | 15篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1977年 | 1篇 |
排序方式: 共有510条查询结果,搜索用时 15 毫秒
151.
废弃印刷线路板熔融盐气化特性研究 总被引:5,自引:0,他引:5
在熔融盐气化炉中进行废弃印刷线路板气化实验,考察了空气当量比对气体产率、气体热值、碳转化率以及气化效率的影响,并对N2气氛下线路板在熔融盐反应器中裂解液体产物通过气质联用仪进行了分析.结果表明,气体产率和碳转化率随着空气当量比增加而增加,空气当量比增加到40%时,气体产率和碳转化率分别达到840 mL·g-1和96%;气体产物热值随着空气当量比增加而减少,气化效率随着空气当量比的增加先增加然后减少,在20%空气当量比气化效率达到最大值94%.液体产物的主要成分为苯酚、2-甲基苯酚、萘等,表明线路板在熔融盐气化炉内的反应过程中,苯环结构上的长链烷烃脂肪烃支链得到脱除,苯基C6H5-O的断裂得到加强,同时发生芳构化反应. 相似文献
152.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) investigated three fatal dust explosions that all occurred in 2003. These explosions caused the deaths of 14 people and injured hundreds more. Two of the facilities were damaged beyond repair, and several hundred employees lost their jobs.
CSB's investigations revealed that the explosions had common causes, despite their geographic and industrial diversity. Consequently, CSB commissioned a study of combustible dust fire and explosion hazards. This paper presents a summary of CSB's findings and recommendations developed during that study. 相似文献
153.
Wildlife resources the world over have long been subject to harvest and management. As wildlife uses have grown, so too have the need and desire to ensure their sustainability.
This new context of sustainability presents opportunities to merge ecological, economic and social elements to foster development. This paper presents the management and harvesting of wild kangaroos as an example of the potentially sustainable use of a natural resource. Some comparisons are drawn between the use of other wild living resources, deer in Europe and crayfish in Western Australia. However, sustainability of kangaroo species and the industry is not just a matter of market economics and ecology, it must also be socially sustainable. The public policy instrument of a statutory advisory board with a marketing function is proposed in order to integrate the cultural and social aspects of kangaroo management with the economic and ecological aspects. Through such integration, full sustainability of a wild resource then might be achieved. 相似文献
154.
A case study of microwave processing of metal hydroxide sediment sludge from printed circuit board manufacturing wash water 总被引:2,自引:0,他引:2
The large quantity of wash water used in the electroplating and etching process in the manufacturing of printed circuit boards (PCBs) contains a high level of heavy metal ions (Cu++, Zn++, Ni++, Cr+++, Pb++). These potentially toxic ions are removed from the wash water effluent through a polyelectrolyte flocculation and hydroxide precipitation process during which a hydroxide sediment sludge rich in metal ions and polymers is generated. This sediment sludge possesses some unique characteristics and properties in terms of composition, fine particle size distribution, high specific surface area, and a tendency to agglomerate after drying. Direct disposal of this classified “special waste” (Department of Environment of Northern Ireland, The Special Waste Regulations, Northern Ireland, 1998) at landfill sites may cause serious soil and underground water pollution through a gradual ionic leaching process. This paper describes an experimental investigation, exploratory in nature, which employs microwave radiation for detoxification of the sediment sludge through microwave heating, drying and metal ion immobilization within the sediment solids. The effectiveness of microwave assisted binding and immobilization of the metal ions within the sediment solids was studied in conjunction with an evaluation of microwave energy efficiency in comparison to the more conventional convective heating and drying processes. Given a sufficient amount of microwave radiation, leaching of Cu2+ and Pb2+ was reduced by 2700% and 1080%, respectively, over a period of 12 weeks, and further leaching was not detectable within six months at simulated local landfill aqueous conditions. This paper also attempts, through experimental observation, to add to the very limited understanding of the complex interactions and binding of free metal ions with the polymeric materials and metal hydroxides under the influence of an electromagnetic field. The high specific surface of the sediment solids and their adsorption properties were further explored and characterized in a study of adsorption of reactive dyes by the microwave processed solids. 相似文献
155.
156.
介绍了配电线路在运行中发生短路、过负荷以及导线或电缆接头处接触电阻过大而引起导线过热、产生火花和电弧引起火灾事故的原因。并针对上述原因 ,提出安全用电 ,预防配电线路发生火灾事故的安全技术措施 相似文献
157.
158.
废印刷电路板的静电分选实验研究 总被引:1,自引:0,他引:1
金属与非金属材料的分离是回收利用废印刷电路板的关键环节。对废印刷电路板物料的静电分选进行了实验研究。实验以电压、辊筒转速、电晕电极与辊筒之间的距离、静电极位置、电晕电极位置、电晕电极数量等为考察因素,研究各因素对电选效果的影响规律。结果表明,影响金属与非金属材料分离的主要因素是电压、辊筒转速和电晕电极与辊筒之间的距离,对于-0.9 0.45mm的破碎物料,当电压为24kV,辊筒转速为15Hz(54.6r/min),电晕电极与辊筒之间的距离为5.2cm时,得到最大静电分选综合效率67.37%。 相似文献
159.
对斜板沉淀池在新钢公司高炉煤气洗涤中的应用研究进行了报道,同时与原系统平流沉淀池从工艺参数和经济性等方面进行了比较。运行结果表明,采用斜板沉淀池节省了投资,使循环水利用率从55%提高92%,出水水质得到显著提高,减少了环境污染。 相似文献
160.
Ionela Birloaga Vasile Coman Bernd Kopacek Francesco Vegliò 《Waste management (New York, N.Y.)》2014,34(12):2581-2586
This study refers to two chemical leaching systems for the base and precious metals extraction from waste printed circuit boards (WPCBs); sulfuric acid with hydrogen peroxide have been used for the first group of metals, meantime thiourea with the ferric ion in sulfuric acid medium were employed for the second one. The cementation process with zinc, copper and iron metal powders was attempted for solutions purification. The effects of hydrogen peroxide volume in rapport with sulfuric acid concentration and temperature were evaluated for oxidative leaching process. 2 M H2SO4 (98% w/v), 5% H2O2, 25 °C, 1/10 S/L ratio and 200 rpm were founded as optimal conditions for Cu extraction. Thiourea acid leaching process, performed on the solid filtrate obtained after three oxidative leaching steps, was carried out with 20 g/L of CS(NH2)2, 6 g/L of Fe3+, 0.5 M H2SO4, The cross-leaching method was applied by reusing of thiourea liquid suspension and immersing 5 g/L of this reagent for each other experiment material of leaching. This procedure has lead to the doubling and, respectively, tripling, of gold and silver concentrations into solution. These results reveal a very efficient, promising and environmental friendly method for WPCBs processing. 相似文献