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641.
《Process Safety and Environmental Protection》2014,92(6):625-636
In this paper we explore the concept of transmission Functions and its application to the resolution of the problem posed by the uncertainty in the time to take manual protective actions due for instance to different operator abilities. This time uncertainty is a very special kind of uncertainty with obvious relevance in Protection Engineering problems. Tackling it involves a large amount of simulations of transients associated to sequences of system transitions, resulting from those actions, where the only difference from one simulation to another is the time interval between transitions, the evolution laws being always the same. In order to solve such type of problems, a new formalism is proposed based on the concept of transmission Function. We prove that for a large class of Multiple Input–Multiple Output (MIMO) piecewise linear systems, the output may be obtained as additive contributions of each interval of the sequence, each one characterized via a Transmission Function. We then provide efficient methods to compute Transmission Functions of sequences of canonical Single Input-Single Output (SISO) piecewise systems, and to find the locus of protective action times that lead to damage (damage domain). 相似文献
642.
Van Der Perk M Burema J Vandenhove H Goor F Timofeyev S 《Journal of environmental management》2004,72(4):770-240
A Monte Carlo analysis of two sequential GIS-embedded submodels, which evaluate the economic feasibility of short rotation coppice (SRC) production and energy conversion in areas contaminated by Chernobyl-derived (137)Cs, was performed to allow for variability of environmental conditions that was not contained in the spatial model inputs. The results from this analysis were compared to the results from the deterministic model presented in part I of this paper. It was concluded that, although the variability in the model results due to within-gridcell variability of the model inputs was considerable, the prediction of the areas where SRC and energy conversion is potentially profitable was robust. If the additional variability in the model input that is not contained in the input maps is also taken into account, the SRC production and energy conversion appears to be potentially profitable at more locations for both the small scale and large scale production scenarios than the model predicted using the deterministic model. 相似文献
643.
Factors affecting private forest landowner interest in ecosystem management: linking spatial and survey data 总被引:1,自引:0,他引:1
Jacobson MG 《Environmental management》2002,30(4):577-583
Many factors influence forest landowner management decisions. This study examines landowner decisions regarding participation
in ecosystem management activities, such as a landscape corridor cutting across their private lands. Landscape corridors are
recognized worldwide as an important tool in biodiversity conservation. For ecosystem management activities to occur in areas
dominated by a multitude of small private forest landholdings, landowner participation and cooperation is necessary. Data
from a survey of landowners combined with an analysis of their land's spatial attributes is used to assess their interest
in ecosystem management. Results suggest that spatial attributes are not good predictors of an owner's interest in ecosystem
management. Other factors such as attitudes and opinions about the environment are more effective in explaining landowner
interest. The results have implications for any land manager using GIS data and implementing ecosystem management activities
on private forestland. 相似文献
644.
Drabek TE 《Disasters》2001,25(1):76-94
When people are advised that their place of employment is threatened with disaster, how do they respond? Interviews with employees (n=406) of 118 businesses affected by one of seven recent disasters provide the first answers to this question. Multivariate analyses document the key variables that best predict variation are: 1) emergent perceptions of risk; 2) time of evacuation from work; 3) time of evacuation from home; 4) multiple evacuations; and 5) tension between work and family commitments. When warned of impending disaster, most employees initially responded with denial. Gradually, however, emergent perceptions of risk intensified especially among those living in communities in which the least amount of disaster planning had occurred or who resided in a mobile home or apartment. Highest levels of work and family tensions during these evacuations were reported by racial minority employees who had children living at home. Policy implications for these and other findings are discussed so as to pin‐point changes business managers should make that will enable them to provide the leadership and compassion expected by employees. 相似文献
645.
Hakan Basaiaoclu Ertürk Celenk Miguel A. Mariulo Nurinnisa Usul 《Journal of the American Water Resources Association》1997,33(2):455-464
ABSTRACT: Geographic Information Systems (GIS) technology is used to identify candidate sites for a solid waste disposal facility in the Gölbasi region of Turkey that has suffered from the negative impact of a current but poorly-located open-dump site on the environment. The municipality of Gölbasi has noticed its deleterious effect on the environment, and has thus decided to dismiss this open-dump site and search for new landfill sites. In this study, the procedure followed under a GIS framework rejects the unacceptable sites considering environmental factors exclusively, other than economic and political issues, contained in the form of multiple layers of attribute information to select the candidate sites for landfilling wastes through an overlay analysis performed by GIS software, ARC/INFO V 7.1. For the spatial data requirements of GIS, a number of thematic map layers (ground water, wetlands and swamp areas, surface water, roads, topographic contours, ecological features, settlements, erosion susceptibility zones, and soil type) are prepared in digital form. In this application, GIS is considered as a screening tool in a site selection process to narrow the number of candidate sites, subsequently leading to one or more sites for detailed investigation. Preliminary ranking for a group of potential sites is done on the basis of simple calculations coupled with on-site field studies. 相似文献
646.
Andres R. Garcia-Martin Frederick N. Scatena Glenn S. Warner Daniel L. Civco 《Journal of the American Water Resources Association》1996,32(6):1259-1271
ABSTRACT: Statistical analysis of watershed parameters derived using a Geographical Information system (GIS) was done to develop equations for estimating the 7d–10yr, 30d–10yr, and 7d–2yr low flow for watersheds in humid montane regions of Puerto Rico. Digital elevation models and land use, geology, soils, and stream network coverages were used to evaluate 21 geomorphic, 10 stream channel, 9 relief, 7 geology, 4 climate, and 2 soil parameters for each watershed. To assess which parameters should be used for further investigation, a correlation analysis was used to determine the independence and collinearity among these parameters and their relationship with low flows. Multiple regression analyses using the selected parameters were then performed to develop the statistical models of low flows. The final models were selected in the basis of the Mallow Cp statistic, the adjusted R2, the Press statistic, the degree of collinearity, and an analysis of the residuals. In the final models, drainage density, the ratio of length of tributaries to the length of the main channel, the percent of drainage area with northeast aspect, and the average weighted slope of the drainage were the most significant parameters. The final models had adjusted standard errors of 58.7 percent, 59.2 percent, and 48.6 percent for the 7d–10yr, 30d–10yr, and 7d–2yr low flows respectively. For comparison, the best model based on watershed parameters that can be easily measured without a GIS had an adjusted standard error of 82.8 percent. 相似文献
647.
This article describes an approach to assessing spatial and temporal land-use and land-cover changes in and adjacent to protected
areas and to the measurement of landscape stability within a protected area. Methods employed include aerial photographic
interpretation and GIS technology. Odum's four-compartment ecosystem model provides the conceptual framework for assessing
landscape stability. The study area is a selected sample of the Upper San Pedro National Riparian Conservation Area in the
high desert grassland of southeastern Arizona. Significant changes were observed in the landscape matrix and riparian ecosystem.
However, when these changes were assessed in the context of Odum's model, the change was nonsignificant. Implications of the
approach and potential applications in protected area management are discussed. 相似文献
648.
本文运用生态经济学、系统工程学和规划论的观点,对如何编制县级生态农业建设规划进行了探讨。提出编制规划的基本思路和应遵循的主要原则,并从现状评价、潜力分析、规划目标、规划方案、重点项目、效益预测和主要措施等方面对规划应包括的主要内容和具体要求进行了系统的阐述。 相似文献
649.
David Karmeli 《Journal of the American Water Resources Association》1978,14(6):1374-1386
ABSTRACT: Land, water, labor, and capital are optimally allocated to crops on a farm, using a procedure that also relates to irrigation frequency and level of improvement in the irrigation system. The procedure is based on formulating outputs and expenditures as well as the functions of irrigation frequency-water and yield. The Generalized Geometric Programming is used to solve the objective function as nonlinear equations are involved. 相似文献
650.
David W. Hendricks Brian A. Janonis Steven Gerlek Joseph C. Goldbach James L. Patterson 《Journal of the American Water Resources Association》1982,18(2):279-288
ABSTRACT: The application of a water balance model in finding “solutions” to the supply/demand problem was demonstrated using the South Platte River basin as a case study. Solutions were ascertained by hand, using both “average” and “stress” supply/demand conditions, and were developed for 1980, 2000, and 2020; nonquantifiable boundary conditions were incorporated by judgement. The solution obtained for a particular set of conditions is not unique and has strong normative characteristics; thus it must be judged by various interest groups having different ethical positions. The water balance model has a tabular display format and so the “model” is merely a simple table, i.e., a “water balance table.” In this work the water balance table was displayed on an eight-foot by eight-foot color-coded magnetic board. The board provides a means to both find and display the needed supply/demand “solution.” The tabular display facilitates understanding of the systemwide solution and the formulation of value judgments. Based upon these value judgments and an initial “straw man” solution, successive negotiated solutions can be found which can minimize “conflict.” 相似文献