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311.
ABSTRACT: Accurately estimating the price elasticity of demand for irrigation electricity is important to major electricity suppliers such as the Bonneville Power Administration (BPA) of the Pacific Northwest. The BPA has a revenue maximization objective, and the elasticity of demand is central to its rate setting process. Several studies have attempted to estimate demand for irrigation electricity, but none has explicitly included federal agricultural policy and program variables. Tins paper discusses how agricultural programs may influence farmers irrigation decisions and thus their demand for irrigation electricity. It suggests that existing programs serve to make farmers more responsive to electricity rate increases than would otherwise be the case. Thus, studies that fail to include them may underestimate the responsiveness of farmers to electricity rate increases.  相似文献   
312.
ABSTRACT: Relevant literature was reviewed from which a model of residential water conservation was developed. Four residential conservation program interventions were posited: 1) public education, 2) pricing variables, 3) water use restrictions, and 4) building code requirements. Four exogenous variables affecting residential water use were also posited: 1) temperature, 2) rainfall, 3) household income, and 4) household size. The impacts of these eight variables on residential per capita daily use were assessed by cross sectional and time series analysis. Study results generally supported the porposed model, with less consistent support obtained for pricing variables and conservation beliefs. The paper concludes with the hypothesis that an inclining block rate structure coupled with an informational program designed to inform consumers of their consumption under each block will have a synergistic impact.  相似文献   
313.
Access to water for domestic and irrigation uses remains limited across Sub-Saharan Africa, particularly in rural areas. While the technical feasibility of implementing innovative technologies to improve water supply has been often evaluated, less is known about the drivers that motivate users to pay for obtaining the inherent benefits of improved water supply. In this article, the determinants of the marginal willingness to pay (mWTP) for improved domestic and irrigation water are investigated. For this purpose, a contingent valuation study is performed in rural Rwanda. This study uses survey data from 316 households situated in 8 villages, in which ~20% of the households receive electricity thanks to microgrids powered by solar energy. It is found that the mWTP for improved domestic water supply is influenced by the proportion of children in the household, business ownership, and satisfaction with water quantity and quality. The mWTP for irrigation is determined by respondent education, business ownership and crop area planted. This paper contributes to the literature by allowing a comparison of the determinants of the mWTP for improved domestic water supply to the determinants of the mWTP for irrigation. Another contribution is to examine the mWTP for improved water infrastructure in partially electrified villages. Identifying areas with high marginal benefits from water can guide infrastructure investment and electrification efforts while improving well-being and increasing revenues in rural areas.  相似文献   
314.
污水资源化问题分析与对策   总被引:10,自引:0,他引:10  
污水资源化是解决我国目前存在的严重水危机的有效途径。从我国水危机现状出发,分析了目前实施污水资源化过程中存在的政策、管理、资金、技术设备等多方面问题,并提出了相应对策。  相似文献   
315.
为探究MFC(microbial fuel cells,微生物燃料电池)对人工湿地(constructed wetland,CW)堵塞物EPS(extracellular polymeric substances,胞外聚合物)组分的处理效果和产电性能,构建双室MFC,设置闭路组(closed circuit MFC,MFC-C)和开路组(open circuit MFC,MFC-O)对EPS中的主要组分〔PN(protein,蛋白质)和PS(polysaccharide,多糖)〕及人工湿地堵塞物进行处理,分析底物类型、底物浓度和外阻(Rex)对MFC系统产电性能的影响及系统对底物的处理效果.结果表明:①MFC系统的产电性能受底物类型、底物浓度及Rex的影响较大,底物浓度增加1.5倍(由200 mg/L增至500 mg/L)时,MFC系统最大电压(Vmax)增加5.8%(PN),最大功率密度(Pmax)分别增加188.30%(PN)和124.21%(PS);保持底物类型和底物浓度不变,Rex增加9倍(由100 Ω增至1 000 Ω)时,MFC的Vmax分别增加110.26%(PN)和92.81%(PS),Pmax分别增加109.19%(PN)和7.51%(PS).②PN可全部被阳极微生物利用,但同时阳极微生物会分泌PS,底物浓度增加1.5倍时,出水中ρ(PS)分别增加107.85%(MFC-C)和78.55%(MFC-O);Rex增加9倍时,ρ(PS)分别增加415.85%(MFC-C)和294.29%(MFC-O);底物为PN时,出水中ρ(PS)均表现为MFC-C < MFC-O,说明MFC形成的微弱电场在一定程度上可抑制PS的分泌.③人工湿地堵塞物可作为MFC的底物,随着投加量的增加(除堵塞物投加量为0.500 g/L外),Vmax(约750 mV)变化不大,但电压稳定时间随投加量的增加而略有延长;堵塞物投加量为6.667 g/L时,MFC的Pmax为12.25 mW/m2,内阻(Rint)为1 112.5 Ω,MFC产电性能下降.研究显示,人工湿地堵塞物EPS可以作为MFC的阳极底物并同步实现能源回收.   相似文献   
316.
对于工业用水而言,价格杠杆的有效性以及用水价格上涨能否提升工业用水重复利用率,对推进工业节水以及工业转型发展具有重要意义。基于2016年中国地级以上城市的216个数据,利用联立方程处理内生性问题,其三阶段回归结果估计所得工业用水价格弹性为-3.423,即价格每上涨1%,工业用水需求量将减少3.42%,这一结果高于农业、居民生活用水价格弹性。另外,进一步从工业用水特征出发,研究讨论价格杠杆能否提高工业用水重复利用率。分别运用普通最小二乘法和加权最小二乘法探讨水价对工业用水重复利用率的影响,结果表明:水价与工业用水重复利用率显著正相关。因此,提高工业水价能促进工业循环用水,进而实现节约用水。  相似文献   
317.
分析我国农网改造中箱式变电站发展的新趋势,针对一些变电站运行的安全问题,笔者提出以箱变的外形结构、内部构造、独立模块为主的八防功能———防火、防凝露和凝霜、防水、防高温、防低温、防潮、防腐蚀、防小动物进入以及新的防雷与接地的设计方案;阐述改进箱变安全的实施方法,并在ZXW1-35(10)系列智能型无人值守箱式变电站中应用。使用证明,对比国家电气安全标准,该箱式变电站在偏僻之处,特别是在多雷地区,箱式变电站中的一次、二次及通讯设备不会被破坏并将损坏降到最低限度,能够保证电网的正常运行,同时符合国家电气设备安全质量标准。随着新科技成果的推广和应用,箱变的安全性和电网运行的质量得到进一步提高。  相似文献   
318.
价格对中国煤矿事故的影响分析   总被引:1,自引:2,他引:1  
针对我国目前煤炭产业严峻的安全形势,本文采用、统计的方法,分析了煤炭价格和产量与煤矿安全生产事故之间的相关关系,验证煤炭价格与煤矿安全生产事故的发生存在协整关系,而且煤价是煤矿伤亡事故的致因,并进一步做回归分析,并尝试从价格的角度揭示煤矿安全生产事故发生的规律。  相似文献   
319.
ABSTRACT: This work establishes an industrial water demand (IWD) model for a short term estimate, which considers water reuse technologies and discharge regulations, for the integrated circuit (IC) industry in northern Taiwan. Based on the optimization of an industrial water cost system, a computerized system dynamics model (SD model) is developed to generate individual firm IWD using data from year 2000. A market IWD is further constructed for 25 1C firms in the study area and is approximated by an inverse logistic curve. Analytical results demonstrate that price elasticity varies with water price in cases involving water reuse.  相似文献   
320.
This article aims to measure the effects of a flood control project planned for the Chitose River Basin in Hokkaido Prefecture, Japan, using hedonic land price functions. In these functions, "annual expected depth of flood water" is introduced as an explanatory variable to represent the effect of the flood control project. Comparing the approach with the method of "the economic analysis of flood control projects", which has been a conventional evaluation method widely used in Japan, the efficiency and limitations of our approach are discussed.  相似文献   
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