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171.
Rangeland Fire Protection Associations (RFPAs) are volunteer-based groups of trained private landowners who are authorised to respond to events in partnership with governmental agencies. This study analysed the functioning and structure of RFPAs in Idaho and Oregon in the western United States to characterise this under-researched model of disaster response. RFPAs represent an expanding type of disaster response organisation that interfaces with established fire suppression entities, yet ‘emergent behaviour’ manifested in some RFPA response actions. This appeared to lessen and mediate with time, as well as due to recognition of the issues, increased experience of fires, and training that fostered new mutual understandings. There is a need for continued examination of the effect of repeat experience in developing the characteristics of disaster response organisations. In addition, it is crucial to know how the interface between established and other types of organisations may be enhanced to make cooperative disaster response more effective.  相似文献   
172.
The purpose of this study was to help to inform policy development for the Australian rangelands, and provide a proof of concept for application of a multi-criteria analysis approach to assessment of competing resource use at continental scale. The study aimed to identify and locate key natural resource and agricultural production assets in the rangelands, define a number of measures of potentially threatening processes, and use a multi-criteria approach to identify areas where threatening processes, agricultural production problems, or valuable natural resources coincided. The analysis used 35 readily available, continental spatial data layers at 5-km pixel resolution ranked from 1 (low) to 5 (high) under three themed groupings: natural resource base, production base, and threatening processes. These measures were aggregated into composite indicators to define attributes such as environmental sensitivity and total grazing pressure. The composites were then compared in a two-way analysis to explore particular interactions between threatening processes such as pastoralism and mining, and the condition of production and natural resource assets. These interactions were defined as “tensions” for purposes of this analysis. Example “tensions” included the association of high grazing intensity with areas of high environmental sensitivity, indicating a risk of land degradation under adverse climatic conditions. A summary of patterns of tension was obtained by extracting area proportions of high-tension classes for selected Natural Heritage Trust Regions, which are a basis for Australian Government funding of improved environmental management. The study provides a basis for further examination of trade-offs in the use of natural assets, opportunities for improved productivity and sustainability, and social and economic implications.  相似文献   
173.

Purpose  

Feral oilseed rape has become widespread in Europe on waysides and waste ground. Its potential as a source of GM impurity in oilseed rape harvests is quantified, for the first time, by a consistent analysis applied over a wide range of study areas in Europe.  相似文献   
174.
The aim of this work is to investigate atmospheric flow and dispersion of contaminants in the vicinity of single buildings under different stability conditions. The mathematical model used is based on the solution of equations of conservation of mass, linear momentum and energy with the use of a non-standard κ? turbulence model. The modifications proposed in the κ? model are the inclusion of the Kato and Launder correction in the production of turbulent kinetic energy and the use of a modified wall function. Results are presented of numerical simulations of dispersion around a cubical obstacle, under neutral, stable and unstable atmospheric conditions. Experimental data from wind tunnel and field trials obtained by previous authors are used to validate the numerical results. The numerical simulation results show a reasonable level of agreement with field and wind tunnel concentration data. The deviation between model results and field experimental data is of the same order as the deviation between field and wind tunnel data.  相似文献   
175.
A high-throughput screening method using selective pressurized liquid extraction (SPLE) and enzyme-linked immunosorbent assay (ELISA) for monitoring dioxins in sediment and soil is described. SPLE conditions were developed by extracting sediment or soil together with alumina, 10% AgNO3 in silica, and sulfuric acid impregnated silica (acid silica) using dichloromethane (DCM) as the solvent at 100 °C and 2000 psi. Post-extraction cleanups were not required for ELISA. Two reference sediments (National Institute of Standards and Technology SRM 1944 and Wellington Laboratories WMS01) were analyzed by the SPLE–ELISA method. The ELISA utilized a polyclonal antibody and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as the calibrant. Recoveries of ELISA-derived TCDD equivalents (EQ) relative to the expected gas chromatography/high resolution mass spectrometry (GC/HRMS) derived dioxin toxic equivalent (TEQ) values were 116 ± 11% for SRM 1944 and 102 ± 13% for WMS01. ELISA TCDD EQs were consistent with the dioxin TEQs as measured by GC/HRMS for 25 soil/sediment samples from seven different contaminated sites. The ELISA had an approximate method detection limit of 10 pg g−1 with a precision of 2.6–29% based on the relative percentage difference (%RPD) for duplicate samples. Estimated sample throughput for the SPLE–ELISA was three times or more than that of the GC/HRMS method employing PLE with a multi-column cleanup.  相似文献   
176.
Developing a globally responsive Science‐Practitioner‐Humanist model (Lefkowitz, 2008 ) means articulating professional values (supply) and meeting global demand. The United Nations' Millennium Development Goals (MDGs) seek to halve human poverty by 2015 and how organizations respond to this constitutes a formidable demand on Organizational Psychology. A key process for delivering more effective aid is the Paris Declaration on Aid Effectiveness, which seeks collaborative contributions from a plethora of Organizations, including business organizations and professions like ours. We argue that a thoughtful articulation of what Organizational Psychology uniquely stands for, and can offer, is therefore needed. It is proposed that a key mechanism for addressing this challenge is a Task Force, whose functions will include the coordination of institutions within psychology, and linking them to those in development. We describe such a task force and outline its core mission (Reichman, Frese, Schein, Carr, MacLachlan, & Landy, 2008 ). Organizational Psychology's response to poverty reduction should meet Lefkowitz's criteria for developing a more humanist model of science and practice as the MDGs are inherently humanist and values‐based. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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This paper examines the impact of climate change on the decision of farmers to engage or not to engage in livestock activities and also on the choice of different livestock species in Kenya. To this end, cross‐sectional household level data supplemented by long‐term averages of climate data are used. The probit model is employed to derive the response of the probability of engaging in livestock activities to climate change. Probit and multivariate probit methods are employed to model the choice of different livestock species. Atmosphere–ocean global circulation models are used to project the impact of different climate scenarios on the probability of engaging in livestock activities and also of adopting different livestock species according to variations in climate. The results suggest that farmers adapt livestock management decisions to climate change. At low levels of temperature increase, the probability of engaging in livestock activities falls, but at higher levels of climate change, the probability rises. The results further show that as it gets hotter, farmers change their livestock choices from dairy cattle and sheep to beef cattle and goats.  相似文献   
180.
Many regions worldwide are experiencing rapid urbanization, and often along with growth in the local economy and population comes worsening air quality. Such regions typically find that addressing the additional challenge of polluted air is difficult. This paper reports the results of an assessment of the present health and related economic costs of poor air quality in the San Joaquin Valley of California. Further, it suggests how such assessments can support strategies to pursue pollution reductions that offer the largest near-term gains, by rigorously modeling the associations between pollution levels, demographic groups, and recognized adverse health effects.  相似文献   
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