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411.
我国水资源管理现状及对策 总被引:11,自引:0,他引:11
从建立水资源管理体系、水资源管理法规等方面介绍了我国水资源管理的现状,指出我国的水资源管理存在水平落后、市场化程度低、体制和政策上存在弊端以及忽视节水方针的实施等问题,提出了,通过倡导新的生态经济管理思想、建立国家统一的水资源管理体系、以市场为导向进行水资源管理、建设节水型社会和采用先进技术等解决问题的办法。 相似文献
412.
运用深圳市市政环卫综合处理厂十几年来的运行经验和科研成果,探讨、分析了城市生活垃圾焚烧发电设施稳定运行的关键工艺,阐明系统稳定运行的重要工艺环节,并详细说明工艺的操作方法。 相似文献
413.
414.
Richard Frye James W. McFarland 《Journal of the American Water Resources Association》1980,16(1):31-35
ABSTRACT: The traditional “requirements” approach to water system planning presumes perfectly inelastic demand and arbitrarily selects a fixed water requirement per capita per day as a planning target. Economists have often pointed out that such a policy leads to over-investment in water supply facilities; a superior approach would maximize some measure of net benefits incorporating price-sensitive demand. Using a dynamic programming model to depict an investment problem in Rhode Island, we find that ambiguities about how to incorporate price-sensitive demand into a decision framework may make such an approach as arbitrary as the requirements approach. Water conservation responses may be a function of other social parameters than water price; if so, variations in these social parameters should be regarded as economic alternatives to water supply investments. 相似文献
415.
Alexander E. Cassuto Stuart Ryan 《Journal of the American Water Resources Association》1979,15(2):345-353
ABSTRACT: This paper develops a model that can be used to forecast the residential elasticity of demand for water within a district. Long-term water conservation programs and revenue and cost decisions hinge crucially on a determination of this elasticity. This study then pools cross-sectional (census) and time series data to generate elasticity forecasts for the Oakland urban area. 相似文献
416.
N. H. Ravindranath I. K. Murthy R. K. Chaturvedi K. Andrasko J. A. Sathaye 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1027-1050
Carbon forestry mitigation potential estimates at the global-level are limited by the absence or simplicity of national-level
estimates, and similarly national-level estimates are limited by absence of regional-level estimates. The present study aims
to estimate the mitigation potential for a large diverse country such as India, based on the GTAP global land classification
system of agro-ecological zones (AEZs), as well the Indian AEZ system. The study also estimates the implications of carbon
price incentive (US$50 and $100) on mitigation potential in the short-, medium- and long-term, since afforestation and reforestation
(A & R) is constrained by lack of investment and financial incentives. The mitigation potential for short and long rotation
plantations and natural regeneration was estimated using the GCOMAP global forest model for two land area scenarios. One scenario
included only wastelands (29 Mha), and the second enhanced area scenario, included wastelands plus long fallow and marginal
croplands (54 Mha). Under the $100 carbon price case, significant additional area (3.6 Mha under the wasteland scenario and
6.4 Mha under the enhanced area scenario) and carbon mitigation is gained in the short-term (2025) compared to the baseline
when using the GTAP land classification system. The area brought under A & R increases by 85–100% for the $100 carbon price
compared to $50 carbon price in the short-term, indicating the effectiveness of higher carbon price incentives, especially
in the short-term.
A comparison of estimates of mitigation potential using GTAP and Indian AEZ land classification systems showed that in the
short-term, 35% additional C-stock gain is achieved in the $100 carbon price case in the enhanced area scenario of the Indian
AEZ system. This difference highlights the role of the land classification system adopted in estimation of aggregate mitigation
potential estimates, particularly in the short-term. Uncertainty involved in the estimates of national-level mitigation potential
needs to be reduced, by generating reliable estimates of carbon stock gain and losses, and cost and benefit data, for land
use sector mitigation options at a scale disaggregated enough to be relevant for national mitigation planning. 相似文献
417.
在土地利用规划中,对线性规划结果进行影子价格计算可以确定其结果在最优状况时,放宽某个约束条件(aijxi=bi)对目标函数(S)产生的附加贡献值。而敏感性分析解决了在线性规划仍保持最优解情况下,所允许的因市场条件和生产过程的改变导致的资源限制且(bi)和利益系数(ci)的可行变化范围。通过以上计算和分析,使静态的线性规划模型向动态模型方向迈进了一步。为其在一定空间和时间上推广应用开拓了余地。 相似文献
418.
目前小城镇日常生活中可回收利用的废品主要是通过废品回收部门流向废品再利用工厂.废品回收部门主要依赖于废品再利用工厂生存.规模较大的个人废品收购商对专业化废品收购商的冲击以及废品再利用工厂的收购价格低、技术水平低、有限的收购种类和二次污染严重等已成为废品向资源化产品转化的制约因素.完善废品回收利用渠道和加强政府的支持力度对于促进废品类物质的资源化具有重要意义. 相似文献
419.
Hiramatsu Ai Hanaki Keisuke Aramaki Toshiya 《Mitigation and Adaptation Strategies for Global Change》2003,8(3):293-310
The Clean Development Mechanism (CDM) was adopted in the Kyoto Protocol as a flexibility mechanism to reduce greenhouse gases
(GHGs) and has been started with such projects as improving efficiency of individual technology. Although applying various
countermeasures to urban areas has significant potentials for reducing GHGs, these countermeasures have not been proposed
as CDM projects in the practical stage. A CDM project needs to be validated that it will reduce GHGs additionally compared
with a baseline, that is, a predictive value of GHG emissions in the absence of the project. This study examined the introduction
of solid waste incineration with electricity generation into three different cities, A, B and C. The combination of main solid
waste treatment and fuel source are landfill and coal, respectively, in City A, incineration and natural gas in City B, and
landfill and hydro in City C. GHG emission reductions of each city under several baseline options assumed here were evaluated.
Even if the same technology is introduced, the emission reduction greatly varies according to the current condition and the
future plan of the city: 1043–1406 kg CO2/t of waste in City A, 198–580 kg CO2/t in City B, and wide range of zero to over 1000 kg CO2/tin City C. Baseline options also cause significant difference in the emission reduction even in the same city (City C).
Incinerating solid waste after removing plastics by source separation in City B increased GHG emission reduction potential
up to 730–900 kg CO2/t, which enhances the effectiveness as a CDM project.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
420.
The resource basis of industrial energy production is still, to a large extent, in non-renewable fossil fuels, the use of which creates emissions that the ecosystem has difficulty in tolerating. The goal of industrial ecology is to substitute the non-renewable stocks with renewable flows. In this paper, a regional industrial ecosystem that relies on a power plant as its key organisation, as an anchor tenant, is considered in the context of energy production and consumption. The co-production method of heat and electricity (CHP, co-production of heat and power) is implemented in the local power plant. This method uses the waste energy from electricity production for district heat and industrial heat/steam. The fuel basis in a CHP plant can include heterogeneous waste fuels. The method has been applied, to a large extent, in only three countries in the world; Denmark, The Netherlands and Finland. Examples of CHP-based industrial ecosystems from Finland are considered. CHP is reflected upon from the viewpoint of industrial ecosystem principles. 相似文献