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181.
Traditional olive orchards account for a large share of the area under olives in the EU, particularly in marginal areas, like those analysed in the OLIVERO project. In general, traditional olive growing can be described as a low-intensity production system, associated with old (sometimes very old) trees, grown at a low density, giving small yields and receiving low inputs of labour and materials. Though such systems are environmentally sustainable, their economic viability has become an issue, since EU policies favour more intensive and competitive systems. Orchards that have not been intensified seem to be threatened by the recent reform of the EU olive and olive oil policy, as income support has been decoupled from production. The main purpose of this paper is to identify the present constraints to traditional olive growing, and to recommend some private and public interventions to prevent its abandonment. During the OLIVERO project, traditional olive production systems were identified and described in five target areas (Trás-os-Montes-Portugal, Cordoba and Granada/Jaen-Spain, Basilicata/Salerno-Italy, and West Crete-Greece). The causes and consequences of abandonment are discussed, based on the analysis of the costs and returns, which revealed that these systems are barely economically sustainable. Their viability is only assured if reduced opportunity costs for family labour are accepted, and the olive growing is part-time. Based on these results, recommendations are made to prevent the abandonment of traditional olive growing and to preserve its environmental benefits. 相似文献
182.
Miria Lange Ann Winstanley David Wood 《Journal of Environmental Planning and Management》2008,51(3):381-397
Policy makers, economists and water researchers have advocated water transfer and trade as a key potential response to worldwide water scarcity and/or efficiency problems. This paper examines aspects of an operational irrigation scheme in New Zealand that enables transfer of water between shareholders, arguing that the set-up and processes involved with the scheme can provide a wider context for analysis and consideration of social and cultural issues involved with resource allocation. Analysis of the key drivers and barriers for water reveal that while there is potential for real benefits from transferring water for farmers and the community, an examination of some of the processes used, and barriers to transfer reveals important lessons for planning and regulatory perspectives, including the importance of looking at the issues from a procedural and distributive justice viewpoint. 相似文献
183.
Dragutin T. Mihailovic Kiran Alapaty Zorica Podrascanin 《Environmental science and pollution research international》2009,16(2):144-151
Background, aim, and scope Improving the parameterization of processes in the atmospheric boundary layer (ABL) and surface layer, in air quality and
chemical transport models. To do so, an asymmetrical, convective, non-local scheme, with varying upward mixing rates is combined
with the non-local, turbulent, kinetic energy scheme for vertical diffusion (COM). For designing it, a function depending
on the dimensionless height to the power four in the ABL is suggested, which is empirically derived. Also, we suggested a
new method for calculating the in-canopy resistance for dry deposition over a vegetated surface.
Materials and methods The upward mixing rate forming the surface layer is parameterized using the sensible heat flux and the friction and convective
velocities. Upward mixing rates varying with height are scaled with an amount of turbulent kinetic energy in layer, while
the downward mixing rates are derived from mass conservation. The vertical eddy diffusivity is parameterized using the mean
turbulent velocity scale that is obtained by the vertical integration within the ABL. In-canopy resistance is calculated by
integration of inverse turbulent transfer coefficient inside the canopy from the effective ground roughness length to the
canopy source height and, further, from its the canopy height.
Results This combination of schemes provides a less rapid mass transport out of surface layer into other layers, during convective
and non-convective periods, than other local and non-local schemes parameterizing mixing processes in the ABL. The suggested
method for calculating the in-canopy resistance for calculating the dry deposition over a vegetated surface differs remarkably
from the commonly used one, particularly over forest vegetation.
Discussion In this paper, we studied the performance of a non-local, turbulent, kinetic energy scheme for vertical diffusion combined
with a non-local, convective mixing scheme with varying upward mixing in the atmospheric boundary layer (COM) and its impact
on the concentration of pollutants calculated with chemical and air-quality models. In addition, this scheme was also compared
with a commonly used, local, eddy-diffusivity scheme. Simulated concentrations of NO2 by the COM scheme and new parameterization of the in-canopy resistance are closer to the observations when compared to those
obtained from using the local eddy-diffusivity scheme.
Conclusions Concentrations calculated with the COM scheme and new parameterization of in-canopy resistance, are in general higher and
closer to the observations than those obtained by the local, eddy-diffusivity scheme (on the order of 15–22%).
Recommendations and perspectives To examine the performance of the scheme, simulated and measured concentrations of a pollutant (NO2) were compared for the years 1999 and 2002. The comparison was made for the entire domain used in simulations performed by
the chemical European Monitoring and Evaluation Program Unified model (version UNI-ACID, rv2.0) where schemes were incorporated. 相似文献
184.
《International Journal of Sustainable Engineering》2013,6(4):277-291
The function, cost and environmental performance are the primary decision-making factors for scheme selection in green design. For the comprehensive and accurate decision-making in selecting green product design scheme, a quantitative analysis method of multi-attribute decision-making (MADM) is presented. With analysing the multi-attribute of scheme selection, the MADM model is established, which takes environmental impact of materials, disassembly performance, recycling performance, energy efficiency, noise, pollutants to environmental and functional values. Fuzzy technique for order performance by similarity to ideal solution method is applied to solve this model for the feasible solutions. Finally, a case study is given to validate the application of this methodology as a useful design guideline for scheme selection in green design. 相似文献
185.
基于ANN耦合遗传算法的爆破方案选择方法 总被引:5,自引:0,他引:5
为预防露天矿爆破引起的事故,基于安全和经济方面的考虑,对露天矿爆破方案进行优化选择,提出将人工神经网络(ANN)模型与遗传算法(GA)相耦合,从而进行爆破方案优化。研究露天矿爆破可能引起的2种主要危害形式:超爆和飞石,进而确定超爆深度和飞石距离为爆破方案的被优化目标参数。另一方面,炮眼深、间距、装药深度、阻塞深度、单位炸药消耗量和钻孔率对超爆深度和飞石距离的影响是复杂的、非线性的,因而将其作为爆破方案的影响参数。分别用影响参数和目标参数作为ANN的输入值和输出值加以训练,训练后的ANN数据作为GA的适应度函数进行方案优化。结果表明:可找到符合工程实例数据的爆破方案集合,借助Pareto图,可得到相关参数的值最小(超瀑深度为0.6999m,飞石距离为27.3386m)的最优爆破方案。 相似文献
186.
乌鲁木齐地区环境空气中TSP达标方案的探讨 总被引:1,自引:0,他引:1
TSP是乌鲁木齐市大气污染的首要污染物。根据TSP污染源调查和污染物源解析研究成果,对乌鲁木齐市TSP污染现状和污染物来源进行了分析,在对TSP污染进行科学预测的基础上,根据大气污染控制技术研究成果和污染治理经验。提出了TSP达标规划实施方案。 相似文献
187.
188.
189.
分析稳高压消防水系统改造的5种设计方案的特点,对这些改造方案的安全可靠性、运行费用进行分析,为稳压消防水系统改造设计、决策提供参考。 相似文献
190.
预处理-两段好氧工艺处理PTA生产废水的开工运行 总被引:3,自引:0,他引:3
针对Amoco技术PTA生产排水中TA含量高的特点,采用预处理-两段好氧工艺处理该废水在洛阳石化总厂成功地实施了工业运行。介绍了开工过程并对有关问题进行了讨论。 相似文献