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581.
Corporations in the extractive industries often state their commitment to “corporate social responsibility” principles, but their actual implementation of these principles, particularly in developing countries, is questionable. This contradiction between rhetoric and reality is attributable to the fact that these companies have not fully integrated CSR into their business models. This can been seen in assessments of projects' costs and benefits, project and technology selection, respect for community consent, and performance incentive structures. The Marlin gold mine in Guatemala provides a concrete example of these sharp contradictions between stated CSR commitments and actual performance. 相似文献
582.
Corporate social responsibility in the mining industry: Perspectives from stakeholder groups in Argentina 总被引:1,自引:0,他引:1
Since the liberalisation of its investment regime in the 1990s, Argentina has seen a rise in foreign direct investment into large-scale exploration and exploitation of mineral resources. However, many social groups (local communities, grassroots movement and the church) often strongly oppose new mining projects on the grounds of environmental, ethical and economic concerns. In a situation marked by widespread conflict, mining companies continue operating and develop Corporate Social Responsibility (CSR) initiatives which are often promoted as a means of contributing to the sustainability and development of the nation. The paper develops a framework to highlight how the principles of stakeholder theory could be used as conceptual and practical guidance for conflict-resolution oriented CSR policies. The framework is further used to analyse two case studies of conflictive mining projects in Argentina. The paper explores how key stakeholders perceive contribution of CSR to welfare and the socio-economic development of mining communities and sustainable development of the nation. It demonstrates that institutional and social stakeholder networks often strongly oppose the idea of voluntary self-regulation implied by CSR in situations characterised by weak governance. Even though the CSR of companies could be improved in areas of corporate communication, transparency, stakeholder engagement and dialogue, it is not seen as a panacea for the social conflicts in the sector. 相似文献
583.
Over the last two decades, mining and mineral exploration companies have adopted various environmental management practices in response to society’s pressure for better environmental protection. The literature highlights a number of benefits and challenges for companies adopting environmental management practices with the Greek Mining and Mineral Industry (GMMI) facing similar issues. In order to analyze the challenges faced by the GMMI, a Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis was conducted, which examined the strengths, weaknesses, opportunities and threats faced by the industry when adopting environmental management practices. The analysis prescribes policy recommendations both for the government and industry which, if adopted, could facilitate improved environmental performance. 相似文献
584.
At first ‘sustainable mining’ could be perceived as a paradox—minerals are widely held to be finite resources with rising consumption causing pressure on known resources. The true sustainability of mineral resources, however, is a much more complex picture and involves exploration, technology, economics, social and environmental issues, and advancing scientific knowledge—predicting future sustainability is therefore not a simple task. This paper presents the results from a landmark study on historical trends in Australian mining, including ore milled, ore grades, open cut versus underground mining, overburden/waste rock and economic resources. When complete data sets are compiled for specific metals, particular issues stand out with respect to sustainability—technological breakthroughs (e.g. flotation, carbon-in-pulp), new discoveries (e.g. uranium or U), price changes (e.g. Au, boom/bust cycles), social issues (e.g. strikes), etc. All of these issues are of prime importance in moving towards a semi-quantitative sustainability model of mineral resources and the mining industry. For the future, critical issues will continue to be declining ore grades (also ore quality and impurities), increased waste rock and associated liabilities, known economic resources, potential breakthrough technologies, and broader environmental constraints (e.g. carbon costs, water). For this latter area, many companies now report annually on sustainability performance—facilitating analysis of environmental sustainability with respect to production performance. By linking these two commonly disparate aspects—mining production and environmental/sustainability data—it becomes possible to better understand environmental sustainability and predict future constraints such as water requirements, greenhouse emissions, energy and reagent inputs, and the like. This paper will therefore present a range of fundamental data and issues which help towards quantifying the resource and environmental sustainability of mining—with critical implications for the mining industry and society as a whole. 相似文献
585.
586.
In the work presented in this paper, the effect of initial pressure on the lower explosion limit (LEL) of the hybrid nicotinic acid/acetone mixture was investigated through standard explosion tests carried out in the 20 L sphere. From experimental results, the flammability diagram was built in the plane (concentration/minimum explosive concentration) of nicotinic acid versus (concentration/LEL) of acetone. Interestingly, it has been found that, in going from low pressures (P < 1 atm) to high pressures (P > 1 atm), the extension of the flammability region increases. This behavior has been attributed to the fact that the turbulence kinetic energy (and thus the energy dissipation) decreases with increasing initial pressure. Bartknecht's correlation for LEL of hybrid mixtures was modified to take into account the effect of pressure, and two correlations were obtained able to give satisfactory predictions of experimental data at both low pressures and high pressures. 相似文献
587.
Bidar G Pruvot C Garçon G Verdin A Shirali P Douay F 《Environmental science and pollution research international》2009,16(1):42-53
Background, aim, and scope The reclamation of nonferrous metal-polluted soil by phytoremediation requires an overall and permanent plant cover. To select
the most suitable plant species, it is necessary to study metal effects on plants over the time, thereby checking that metals
remain stored in root systems and not transferred to aerial parts. In this purpose, the seasonal and annual variations of
metal bioaccumulation, transfer, and phytotoxicity in Trifolium repens and Lolium perenne grown in a Cd-, Pb-, and Zn-contaminated soil were also studied.
Materials and methods The experimental site was located near a closed smelter. In spring 2004, two areas were sown with T. repens and L. perenne, respectively. Thereafter, the samplings of plant roots and shoots and surrounding soils were realized in autumn 2004 and
spring and autumn 2005. The soil agronomic characteristics, the Cd, Pb, and Zn concentrations in the surrounded soils and
plant organs, as well as the oxidative alterations (superoxide dismutase [SOD], malondialdehyde [MDA], and 8-hydroxy-2′-deoxyguanosine
[8-OHdG]) in plant organs were carried out.
Results Whatever the sampling period, metal concentrations in soils and plants were higher than background values. Contrary to the
soils, the fluctuations of metal concentrations were observed in plant organs over the time. Bioaccumulation and transfer
factors confirmed that metals were preferentially accumulated in the roots as follows: Cd>Zn>Pb, and their transfer to shoots
was limited. Foliar metal deposition was also observed. The results showed that there were seasonal and annual variations
of metal accumulation in the two studied plant species. These variations differed according to the organs and followed nearly
the same pattern for the two species. Oxidative alterations were observed in plant organs with regard to SOD antioxidant activities,
MDA, and 8-OHdG concentrations. These alterations vary according to the temporal variations of metal concentrations.
Discussion Metal concentrations in surrounded soils and plant organs showed the effective contamination by industrial dust emissions.
Metals absorbed by plants were mainly stored in the roots. With regard to this storage, the plants seemed to limit the metal
transfer to their aerial parts over the time, thereby indicating their availability for metal phytostabilization. Aerial deposition
was another source of plant exposure to nonferrous metals. Despite the occurrence of metal-induced oxidative alterations in
plant organs, both plant species seemed to tolerate a high metal concentration in soils.
Conclusions Taken together, these results indicated that T. repens and L. perenne were able to form a plant cover on highly Cd-, Pb-, and Zn-polluted soils, to limit the metal transfer to their aerial parts
and were relatively metal-tolerant. All these characteristics made them suitable for phytostabilization on metal-contaminated
soils. These findings also highlighted the necessity to take into account seasonal and annual variations for a future phytomanagement.
Recommendations and perspectives In this work, the behavior of plant species grown in metal-polluted soil has been studied during 2 years. Obviously, this
time is too short to ensure that metals remain accumulated in the root system and few are transferred in aerial parts over
the time. It is why regular monitoring should be achieved during more than a decade after the settlement of the plant cover.
This work will be completed by the study of the T. repens and L. perenne effects on mobility of metals in order to evaluate the quantities of pollutants which could be absorbed by the biota and
transferred to groundwater. Bioaccessibility tests could be also realized on polluted soils in order to evaluate the phytostabilization
impacts on the exposition risks for humans. 相似文献
588.
为了将微生物处理羽毛工艺产业化,在摇瓶发酵条件优化的基础上进行5L发酵罐工业小试研究,确定了放大发酵条件并根据发酵条件记录对发酵过程进行分析,推测代谢过程中的物质及能量变化及产物形成的动力学模型。在通气气压为0.08MPa,空气流量为2.5L/min及恒温40℃的条件下,产物得率比摇瓶发酵提高了2~3倍,发酵周期缩短了1d。为羽毛废弃物的利用提供了可靠的依据。 相似文献
589.
剩余污泥已成为污水处理厂亟待解决的棘手问题。虽然现有污泥减量技术众多,但或多或少都存在着技术或经济上的不足。蠕虫——L.variegatus应用于污泥减量具有较好的实际效果以及潜在的商业利用价值,因此,近年来受到人们关注。首先,介绍L.variegatus一般习性、对污泥减量的试验效果。然后,对L.variegatus应用于大规模连续系统的要点进行了技术分析。最后,对L.variegatus应用于实际污水处理厂污泥减量的技术与经济的合理性进行分析和估算。 相似文献
590.
蠕虫L. variegatus在污泥减量中的作用与应用前景分析 总被引:1,自引:0,他引:1
剩余污泥已成为污水处理厂亟待解决的棘手问题.虽然现有污泥减量技术众多,但或多或少都存在着技术或经济上的不足.蠕虫--L.variegatus应用于污泥减量具有较好的实际效果以及潜在的商业利用价值,因此,近年来受到人们关注.首先,介绍L.variegatus一般习性、对污泥减量的试验效果.然后,对L.variegatus应用于大规模连续系统的要点进行了技术分析.最后,对L.variegatus应用于实际污水处理厂污泥减量的技术与经济的合理性进行分析和估算. 相似文献