全文获取类型
收费全文 | 250篇 |
免费 | 15篇 |
国内免费 | 53篇 |
专业分类
安全科学 | 30篇 |
废物处理 | 7篇 |
环保管理 | 62篇 |
综合类 | 113篇 |
基础理论 | 40篇 |
污染及防治 | 23篇 |
评价与监测 | 17篇 |
社会与环境 | 21篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 7篇 |
2022年 | 12篇 |
2021年 | 15篇 |
2020年 | 12篇 |
2019年 | 6篇 |
2018年 | 15篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 13篇 |
2014年 | 12篇 |
2013年 | 12篇 |
2012年 | 14篇 |
2011年 | 21篇 |
2010年 | 13篇 |
2009年 | 20篇 |
2008年 | 18篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 6篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 6篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有318条查询结果,搜索用时 15 毫秒
61.
62.
Deng Y Besse-Hoggan P Husson P Sancelme M Delort AM Stepnowski P Paszkiewicz M Gołębiowski M Costa Gomes MF 《Chemosphere》2012,89(3):327-333
Several physico-chemical properties relevant to determine the environmental impact of ionic liquids - aqueous solubility, octanol/water partition coefficient, chromatographically derived lipophilicity and infinite dilution diffusion coefficients in water - were measured in ionic liquids based on pyridinium, ammonium and pyrrolidinium cations with bis(trifluoromethylsulfonyl)imide anions. The influence of the presence of hydroxyl or ester groups in the physico-chemical properties of these liquids was checked. It appeared that the presence of functional oxygenated moieties reduces the lipophilicity of ionic liquids and so decreases the risk of bioaccumulation in environment. 相似文献
63.
渗滤液中有机物在不同氧化还原带中的降解机理与效率研究 总被引:3,自引:1,他引:2
通过土柱模拟实验研究了垃圾渗滤液中的有机污染物在地下环境中的降解机理和效率.结果表明,铁还原带对有机污染物的降解起重要作用,平均降解效率达86.24%,其次是氧还原带、硝酸盐还原带、硫酸盐还原带和产甲烷带,分别平均达到75.93%、79.81%、74.02%和65.09%;厌氧还原环境可能对苯并噻唑、安替吡啉、茚等物质的降解起重要作用;萘、环己酮、部分环烷烃等不易被微生物降解;不同污染物在不同氧化还原带中的最大降解效率也不同,如1,1,1-三氯乙烷和邻二甲苯在硫酸盐还原带中的降解效率最高,分别为80%和71.43%;三氯乙烯和MTBE则在硝酸盐还原带中的降解效率最高,分别为81.25%和92.58%;而苯在硫酸盐还原带和铁还原带中均被全部降解. 相似文献
64.
以中国和八大综合经济区为研究区,全面分析人文因子、土地利用类型、气候因子和地形因子对植被总初级生产力(GPP)空间分异的影响差异.利用MODIS GPP数据、气象数据、土地利用类型、DEM数据、夜间灯光和人口密度数据等,基于Theil-Sen Median趋势分析、Mann-Kendall显著性检验和地理探测器模型,在全国和经济区尺度上分析2000~2020年植被GPP时空变化特征,探测植被空间分异的影响因子及影响因子间的协同机制.结果表明,2000~2020年中国及八大经济区植被GPP整体呈波动上升趋势,呈上升趋势的区域占总面积的84.46%,其中,呈极显著上升区域占19.86%,主要分布在黄河中游综合经济区中部和大西北综合经济区东部.影响因子探测结果表明,湿度、日照时数、降水和土地利用类型是中国植被GPP空间分异的主要影响因子,其中,湿度的影响力最高,q值为0.64.经济区尺度上,湿度、日照时数、降水是影响东北、黄河中游、大西南和大西北综合经济区植被GPP空间分异的主导因子,而人文因子对东部和南部沿海综合经济区植被空间分异的影响较大.交互作用探测结果表明,中国植被GPP空间分异主要... 相似文献
65.
Functional agrobiodiversity (FAB) has severely declined during the last decades. Current efforts to reinforce FAB are mainly focused on single-actor, parcel-based measures, whereas multi-actor landscape approaches are supposed to be more effective. In this paper, we propose a social–ecological framework that structures how different land users at both the parcel and landscape level interact with FAB as a natural resource. Furthermore, we introduce 1 m2 FAB gardens as an interactive multipurpose measurement tool to gather data on ecosystem services in collaboration with land users. The presented action research approach provides new insights on motivations and interests of different land users in FAB and how knowledge exchange can result in a higher motivation to invest in FAB. Using a case study in Flanders, we illustrate the FAB-garden concept and highlight its strengths and necessary considerations to properly complement other research approaches in this social–ecological system.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01382-0) contains supplementary material, which is available to authorized users. 相似文献
66.
在分析主体功能区环境政策需求的基础上,从环境政策目标、政策手段、政策保障三个层面构建了主体功能区环境政策体系框架。初步确立了各类主体功能区环境政策的宏观目标及微观目标;重点研究了环境准入、污染控制、生态补偿、环境经济等政策措施;从环保绩效考核、环境信息公开、资金保障、法律保障等方面探讨了政策保障体系。本研究为进一步深入开展主体功能区环境政策研究奠定了基础,同时可以为开展主体功能区规划等工作提供参考。 相似文献
67.
An interval-parameter fuzzy-stochastic semi-infinite mixed-integer linear programming (IFSSIP) method is developed for waste
management under uncertainties. The IFSSIP method integrates the fuzzy programming, chance-constrained programming, integer
programming and interval semi-infinite programming within a general optimization framework. The model is applied to a waste
management system with three disposal facilities, three municipalities, and three periods. Compared with the previous methods,
IFSSIP have two major advantages. One is that it can help generate solutions for the stable ranges of the decision variables
and objective function value under fuzzy satisfaction degree and different levels of probability of violating constraints,
which are informative and flexible for solution users to interpret/justify. The other is that IFSSIP can not only handle uncertainties
through constructing fuzzy and random parameter, but also reflect dynamic features of the system conditions through interval
function of time over the planning horizon. By comparing IFSSIP with interval-parameter mixed-integer linear semi-infinite
programming and parametric programming, the IFSSIP method is more reasonable than others. 相似文献
68.
Ignatius Ani Madu 《Environment, Development and Sustainability》2009,11(2):265-276
The disparity in both population and wealth distribution in Nigeria by geo-political zones is well recognized. There is also
the recognition that some of the environmental problems in certain sections of the country can be attributed to the imbalance
in both population and wealth distribution. Hence the various agitations for environmental resource control in the country.
What is lacking however is the research that shows the magnitude of the linkages between the disparity and the environmental
degradation in regional context. This provides the basis for this research. To achieve the aim of the research, a STIRPAT
model was employed as an analytical tool. The findings show that the southern geopolitical zones are generally more densely
populated and wealthier than the northern zones. The south is also experiencing a higher degree of environmental resource
degradation attributable to anthropogenic factors. Thus, there is congruence between population density, wealth distribution
and environmental degradation in Nigeria. Therefore the achievement of sustainable environment and development in Nigeria
requires deliberate policies to mitigate the impact of population concentration and wealth creation on the environment.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
69.
A number of inexact programming methods have been developed for municipal solid waste management under uncertainty. However, most of them do not allow the parameters in the objective and constraints of a programming problem to be functional intervals (i.e., the lower and upper bounds of the intervals are functions of impact factors). In this study, a flexible interval mixed-integer bi-infinite programming (FIMIBIP) method is developed in response to the above concern. A case study is also conducted; the solutions are then compared with those obtained from interval mixed-integer bi-infinite programming (IMIBIP) and fuzzy interval mixed-integer programming (FIMIP) methods. It is indicated that the solutions through FIMIBIP can provide decision support for cost-effectively diverting municipal solid waste, and for sizing, timing and siting the facilities’ expansion during the entire planning horizon. These schemes are more flexible than those identified through IMIBIP since the tolerance intervals are introduced to measure the level of constraints satisfaction. The FIMIBIP schemes may also be robust since the solutions are “globally-optimal” under all scenarios caused by the fluctuation of gas/energy prices, while the conventional ones are merely “locally-optimal” under a certain scenario. 相似文献
70.
Total annual nutrient loads are a function of both watershed characteristics and the magnitude of nutrient mobilizing events.
We investigated linkages among land cover, discharge and total phosphorus (TP) concentrations, and loads in 25 Kansas streams.
Stream monitoring locations were selected from the Kansas Department of Health and Environment stream chemistry long-term
monitoring network sites at or near U.S. Geological Survey stream gauges. We linked each sample with concurrent discharge
data to improve our ability to estimate TP concentrations and loads across the full range of possible flow conditions. Median
TP concentration was strongly linked (R
2 = 76%) to the presence of cropland in the riparian zones of the mostly perennial streams. At baseflow, discharge data did
not improve prediction of TP, but at high flows discharge was strongly linked to concentration (a threshold response occurred).
Our data suggest that on average 88% of the total load occurred during the 10% of the time with the greatest discharge. Modeled
reductions in peak discharges, representing increased hydrologic retention, predicted greater decreases in total annual loads
than reductions of ambient concentrations because high discharge and elevated phosphorus concentrations had multiplicative
effects. No measure of land use provided significant predictive power for concentrations when discharge was elevated or for
concentration rise rates under increasing discharge. These results suggest that reductions of baseflow concentrations of TP
in streams without wastewater dischargers may be managed by reductions of cropland uses in the riparian corridor. Additional
measures may be needed to manage TP annual loads, due to the large percentage of the TP load occurring during a few high-flow
events each year. 相似文献