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991.
Framework for integrating indigenous and scientific knowledge for disaster risk reduction 总被引:2,自引:0,他引:2
A growing awareness of the value of indigenous knowledge has prompted calls for its use within disaster risk reduction. The use of indigenous knowledge alongside scientific knowledge is increasingly advocated but there is as yet no clearly developed framework demonstrating how the two may be integrated to reduce community vulnerability to environmental hazards. This paper presents such a framework, using a participatory approach in which relevant indigenous and scientific knowledge may be integrated to reduce a community's vulnerability to environmental hazards. Focusing on small island developing states it presents an analysis of the need for such a framework alongside the difficulties of incorporating indigenous knowledge. This is followed by an explanation of the various processes within the framework, drawing on research completed in Papua New Guinea. This framework is an important first step in identifying how indigenous and scientific knowledge may be integrated to reduce community vulnerability to environmental hazards. 相似文献
992.
1ScopeIn the Sun Jia Catchment several gauging in-stallations are carefully put up to elucidate the hy-drology and the matter fluxes through the catch-ment.At present,it is already possible to quantifydistinct spatial differences in principal water flu-xes.The setup bears the potential to further deep-en the understanding of the small scale processesinvolved in lateral water fluxes and soil erosion.Multi-point monitoring of soil water potentials atvarious soil depths together with hydrograph… 相似文献
993.
The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector. 相似文献
994.
中小化工燃煤锅炉烟气脱硫技术路线的选择 总被引:1,自引:1,他引:0
在分析了燃煤烟气脱硫方式以及中小化工燃煤锅炉特点的基础上,对中小化工燃煤锅炉适宜的烟气脱硫技术路线进行了技术经济比较.认为选择脱硫路线时应考虑技术的成熟度及可靠性、脱硫剂和运行的成本、副产物的利用等因素.建议在烟气量小于8×105 m3/h时采用干法脱硫工艺;在烟气量大于8×105 m3/h时采用石灰石-石膏法脱硫工艺... 相似文献
995.
胡振鹏 《长江流域资源与环境》2012,21(3):259-267
在鄱阳湖流域生态修复中,坚持“保护优先,自然恢复为主,人工修复遵循客观规律”的修复方法:(1)对具有典型意义的生态系统,划定保护区,加强管理,保护濒危物种,增加生物多样性;(2)对中、轻度损害的生态系统,实行封育保护,减轻负荷压力,利用生态系统自组织功能,自然恢复为主;(3)对于严重损害的生态系统,遵循生态系统生长发育的自然规律,采取人工措施修复或重建。科学选择了修复策略:(1)以修复植被生态系统为基础和前提,创造条件,利用生态系统的自组织、自修复能力逐步实现微生物、动物的恢复;(2)把生态修复与发展生态经济结合起来,增加群众收入,提高参与生态修复的主动性和积极性。经过20多年的生态修复,鄱阳湖流域森林覆盖率由311%提高到5832%;同时探索出一条可行的技术路线:(1)通过综合科学考察,掌握生态系统受损害的状况和原因,揭示相关生态系统发育、演替的客观规律;(2)着力研究生态恢复的生态学过程与机制,寻求有效的修复方法、措施和模式;(3)自主创新、试验示范、试点先行、样板引领;(4)以生态保护和建设的大项目为载体,全面展开、系统推进 相似文献
996.
论小城镇核心竞争力的构建和提升 总被引:2,自引:0,他引:2
小城镇作为中国城镇化进程的重要组成部分,对于我国城镇发展的作用举足轻重.研究我国小城镇的核心竞争力问题,有助于加深对小城镇经济发展的认识,帮助政府部门从更高的层次制定小城镇经济发展战略.本文界定了小城镇核心竞争力的概念,探讨了培育和提升小城镇经济核心竞争力的重要意义,并从自然环境、人文环境、基础设施、软件环境、创新能力及产业集群等方面对小城镇核心竞争力的构成进行分析;针对小城镇核心竞争力的构建和提升,提出了优化小城镇发展环境,完善小城镇创新体系,增强小城镇产业集群的发展等建议;得出了发展小城镇经济的关键是要增强其竞争力,而要保持小城镇经济持续的竞争优势,关键在于小城镇经济核心竞争力的培育和提升的结论,为促进我国小城镇经济的持续、快速发展及核心竞争力的构建与提升提供参考和借鉴. 相似文献
997.
Approach of technical decision-making by element flow analysis and
Monte-Carlo simulation of municipal solid waste stream 总被引:2,自引:0,他引:2
This paper deals with the procedure and methodology which can be used to select the optimal treatment and disposal technology of municipal solid waste (MSW), and to provide practical and effective technical support to policy-making, on the basis of study on solid waste management status and development trend in China and abroad. Focusing on various treatment and disposal technologies and processes of MSW, this study established a Monte-Carlo mathematical model of cost minimization for MSW handling subjected to environmental constraints. A new method of element stream (such as C, H, O, N, S) analysis in combination with economic stream analysis of MSW was developed. By following the streams of different treatment processes consisting of various techniques from generation, separation, transfer, transport, treatment, recycling and disposal of the wastes, the element constitution as well as its economic distribution in terms of possibility functions was identified. Every technique step was evaluated economically. The Mont-Carlo method was then conducted for model calibration. Sensitivity analysis was also carried out to identify the most sensitive factors. Model calibration indicated that landfill with power generation of landfill gas was economically the optimal technology at the present stage under the condition of more than 58% of C, H, O, N, S going to landfill. Whether or not to generate electricity was the most sensitive factor. If landfilling cost increases, MSW separation treatment was recommended by screening first followed with incinerating partially and composting partially with residue landfilling. The possibility of incineration model selection as the optimal technology was affected by the city scale. For big cities and metropolitans with large MSW generation, possibility for constructing large-scale incineration facilities increases, whereas, for middle and small cities, the effectiveness of incinerating waste decreases. 相似文献
998.
Aluminum salt coagulants were used prevalently in various water works.In this article,the effects of filtration on residual aluminum concentration and species distribution were researched by determining the concentration of diiferent aluminum species before and after single layer filter,double layer filter,and membrane filtration units.In the research,size exclusion chromatography(SEC)was used to separate colloidal and soluble aluminum,ion exchange chromatography(IEC)was used to separate organic and inorganic aluminum, and inductivity coupled plasma-atomic emission spectrometry(ICP-AES)was used to determine the aluminum concentration.The results showed that the rapid filtration process had the ability of removing residual aluminum from coagulant effluent water,and that double layer filtration was more effective in residual aluminum removal than single layer filtration,while nano filtration was more effective than micro filtration.It was found that when the residual aluminum concentration was below 1mg/L in sediment effluent,the residual aluminum concentration in treated water was above 0.2 mg/L.The direct rapid filtration process mainly removed the suspended aluminum.The removal of soluble and colloidal aluminum was always less than 10% and the natural small particles that adsorbed the amount of soluble or small particles aluminum on their surface were difficult to be removed in this process.Micro filtration and nano filtration were good technologies for removing aluminum;the residual aluminum concentration in the effluent was less than 0.05 mg/L. 相似文献
999.
Simultaneous nitrification and denitrification in step feeding biological
nitrogen removal process 总被引:4,自引:1,他引:3
The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates.Biological occunenee of simultaneous nitrification and denitrification was verified in the aspect of nitrogen mass balance and alkalinity.The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate.In each experimental run the floc sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitriflcation could occur with very small size of floc. 相似文献
1000.