全文获取类型
收费全文 | 1500篇 |
免费 | 157篇 |
国内免费 | 212篇 |
专业分类
安全科学 | 155篇 |
废物处理 | 24篇 |
环保管理 | 313篇 |
综合类 | 785篇 |
基础理论 | 239篇 |
污染及防治 | 55篇 |
评价与监测 | 99篇 |
社会与环境 | 165篇 |
灾害及防治 | 34篇 |
出版年
2024年 | 6篇 |
2023年 | 19篇 |
2022年 | 48篇 |
2021年 | 50篇 |
2020年 | 44篇 |
2019年 | 45篇 |
2018年 | 45篇 |
2017年 | 64篇 |
2016年 | 65篇 |
2015年 | 71篇 |
2014年 | 57篇 |
2013年 | 92篇 |
2012年 | 107篇 |
2011年 | 111篇 |
2010年 | 112篇 |
2009年 | 89篇 |
2008年 | 75篇 |
2007年 | 136篇 |
2006年 | 109篇 |
2005年 | 70篇 |
2004年 | 53篇 |
2003年 | 57篇 |
2002年 | 47篇 |
2001年 | 35篇 |
2000年 | 50篇 |
1999年 | 35篇 |
1998年 | 26篇 |
1997年 | 25篇 |
1996年 | 24篇 |
1995年 | 18篇 |
1994年 | 12篇 |
1993年 | 16篇 |
1992年 | 17篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有1869条查询结果,搜索用时 31 毫秒
531.
公路桥梁施工总体安全风险评估方法研究 总被引:1,自引:1,他引:0
为有效控制公路桥梁施工安全风险,提出一种可量化的公路桥梁施工安全风险评估方法。先构建我国公路桥梁施工总体安全风险评估指标体系,并基于蒙特卡洛抽样技术,运用k-s法对该评估指标体系总体分布进行有效检验。在此基础上,在给定的置信区间下对总体安全风险等级阈值进行界定划分,并通过实例进行验证。研究结果表明:该评估方法具有方便、实用、可靠性强的特点。 相似文献
532.
煤矿安全预评价涉及诸多不确定信息,用传统评价方法难以获得可靠的评价结果。为此,将可变模糊模式识别模型与方法引入煤矿安全领域,提出了煤矿安全预评价的可变模糊识别方法。可变模糊识别方法首先根据指标特征值与指标标准特征值矩阵确定样本的级别上下限,然后利用可变模糊模式识别模型对样本进行识别,得到样本在各级别下的相对隶属度,进而计算级别特征值,并以此为依据进行评价。将该方法应用于黄陵双龙煤矿,得出该矿井的安全等级。结果表明:可变模糊识别方法较文献中方法可更准确地给出安全性等级评价结果,为煤矿安全预评价提供一条新的途径。 相似文献
533.
可回收性设计作为绿色设计的核心内容之一,是一种再生设计。以产品的可回收性为切入点,着重分析产品的回收成本与回收价值、回收结构造型的设计特点以及回收设计的时机周期,为优化产品的结构造型设计,提升产品的回收价值提供支持。 相似文献
534.
Climis A. Davos Walter A. Thistlewaite Eugene C. Paik 《Journal of environmental management》1993,37(4)
The ranking of air quality control measures according to a number of evaluation criteria and with the participation of a large number of interested publics is demonstrated. A pilot study for the South Coast Air Quality Management District of California serves as the reference point. Several methodological considerations are addressed, such as: (a) the enhancement of criterion priorities to account for the variability among the performance of the control measures when incommensurable impact levels are applied: (b) the derivation of alternative rankings according to the priorities of potential coalitions; (c) the assessment of the potential acceptability of a collective ranking given the degree of solidarity among participants with similar interest affiliations; and (b) the assessment of the extent to which the performance of specific control measures may override priority differences and lead to insignificant ranking differences. 相似文献
535.
536.
Van Butsic Noelwah R. Netusil 《Journal of the American Water Resources Association》2007,43(3):622-629
Abstract: This paper uses the hedonic price method to estimate the value of an acre‐foot of irrigation water in Douglas County, Oregon. The analysis uses detailed information from 113 arms‐length transactions of farmland for 2000 and 2001. The estimated willingness‐to‐accept of $261 to sell an acre‐foot of irrigation water is consistent with other studies and recent transactions in the study area. Estimates for the value of leasing water are provided using a range of discount rates and leasing periods. 相似文献
537.
浅谈地价评估和管理中的几个问题 总被引:1,自引:0,他引:1
杨学亮 《中国环境管理干部学院学报》2007,17(2):29-30,33
土地价格是土地价值和权益的具体表现,是调节土地利用的重要手段。地价管理在推进土地有偿使用、优化配置土地资源、促进土地市场建设等方面发挥着重要作用。而现行地价体系比较成熟的只有作为国有土地使用权出让标准的一种基准地价,为适应其它土地权利流转的需要,应建立以土地权利为核心的新型地价体系。 相似文献
538.
Dunja Jaber 《Journal of Agricultural and Environmental Ethics》2000,13(1):29-42
In their report for the Swiss government onthe notion of the dignity of creatures, PhilippBalzer, Klaus-Peter Rippe, and Peter Schaber analyzethe relationship between human dignity and the dignityof creatures, taking them as two categoricallydifferent concepts. Human dignity is defined as the``moral right not to be humiliated,' whereas thedignity of creatures is taken to be ``the inherentvalue of nonhuman living beings.' To my mind there isno need to draw a categorical distinction between thetwo concepts. Both notions could be brought togetherunder an all-encompassing concept of the inherentvalue of living beings, humans and non-humans alike,a concept one could name ``the dignity of livingbeings.' Indeed, this very notion underlies theposition taken in the report, although this is notmade explicit by the authors themselves.As the aim of the paper is only to clarify theconcepts used, I do not go beyond this ``internal'critique of their position, i.e., I don't assess howthe claims articulated via these concepts – theclaim that humans and/or creatures have an inherentvalue consisting in a supposed intrinsic good – areto be justified, although I myself would be ratherskeptical that this might be successfully done. 相似文献
539.
Robert Heeger 《Journal of Agricultural and Environmental Ethics》2000,13(1):43-51
The Swiss expert report suggests thatthe inherent dignity of a living being be identifiedwith its inherent value. But the phrase ``inherentvalue of a living being' seems to connote two conceptsof inherent value. One has a morally obligatingcharacter but is counterintuitive because of itsegalitarianism. The other is one of non-moral value.It is more compatible with considered intuitions butinsufficient for substantiating the expert report'sclaim that human beings have moral duties towardsanimals and plants. The paper discusses theseconcepts. Consideration is then given to the problemof how discursive support can be generated for theexpert report's claim that human beings have the moralduty to abstain from impairing those functions andabilities of a nonuman being that members of itsspecies as a rule can practice. 相似文献
540.
Ahmed?SaidEmail author David?K.?Stevens Gerald?Sehlke 《Environment, Development and Sustainability》2005,7(4):453-464
A new approach for evaluating water sustainability is introduced by comparing physical and economic sustainability. To achieve
physical sustainability, water should be available in sufficient quantity and of good quality and used efficiently. The economic
sustainability can be achieved by balancing between costs and values of water. The objectives of this study were to estimate
the physical and economic sustainability of surface water in the Big Lost River, south–central Idaho. The study used a Bayesian
network by building a graphical diagram of nodes representing all significant variables related with the sustainability, such
as water demand, water quality, and the different costs and values of water. The study showed that the likelihood of the physical
sustainability is less than that of the economic sustainability, which is attributed to the scarcity of water in the Big Lost
River.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献