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241.
Nakićenović Nebojša Victor Nadejda Morita Tsuneyuki 《Mitigation and Adaptation Strategies for Global Change》1998,3(2-4):95-131
This paper reviews and analyzes more than 400 scenarios of global and regional greenhouse gas emissions and their main driving forces - population, economy, energy intensity, and carbon intensity - drawn from an extensive literature survey and summarized in a database. This new and growing database is available online, which makes summary statistics on these scenarios widely available. The scenarios in the database were collected from almost 200 different literature sources and other scenario evaluation activities. The ultimate objective of the database is to include all relevant global and regional emissions scenarios. This paper shows how the database can be utilized for the analysis of greenhouse gas emissions ranges across the scenarios in the literature and for the analysis of their main driving forces. The scenarios in the database display a large range of future greenhouse gas emissions. Part of the range can be attributed to the different methods and models used to formulate the scenarios, which include simple spreadsheet models, macroeconomic models and systems-engineering models. However, most of the range is due to differences in the input assumptions for the scenarios, in particular of the main scenario driving forces. Special emphasis is given to an analysis of medians and ranges of scenario distributions and the distributions of the main scenario driving forces in the database. The analysis shows that the range for projected population increase in the world, across the scenarios in the database, is the smallest of all main driving forces (about a factor of 3 in 2100). The range of economic growth, measured by the gross world product, and the range of primary energy consumption vary by a factor of 10 in 2100. Carbon intensity of energy, an indicator of the degree of technological change, varies by nearly two orders of magnitude in the year 2100. In addition, this paper presents the first attempt to analyze the relationships among the main scenario driving forces. Subsequent papers in this special issue give further analyses of the relationships among the main scenario driving forces and their other relevant characteristics. 相似文献
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244.
A study was conducted to investigate the suitability of phosphate recovery from greenhouse wastewaters by using precipitation/crystallization process. More than 90% of the phosphate could be removed from the greenhouse wastewater. Various calcium phosphate salts were obtained in the process; hydroxyapatite [Ca5(PO4)3OH] could be the main product from the precipitates. Phosphate removal was affected by the presence of magnesium ion in wastewaters. An increase of magnesium concentrations in wastewaters decreased phosphate removal rates. The chemical contents of precipitates in terms of calcium, magnesium and phosphate were affected by calcium to magnesium molar ratio. Higher calcium contents were obtained at wastewaters with high calcium to magnesium molar ratio. An addition of magnesium did not affect the potassium contents in the precipitates. K-struvite, MgKPO4 x 6H2O, was not the major product in the precipitate, even with addition of a large quantity of magnesium. 相似文献
245.
Steven D. Warren Victor E. Diersing Pamela J. Thompson William D. Goran 《Environmental management》1989,13(2):251-257
The universal soil loss equation (USLE) has been integrated with a geographic information system known as the geographical resources analysis support system (GRASS) to create a land classification system for use by military trainers and land managers to minimize the environmental impacts of military training activities. The USLE provides an estimate of current average annual sheet and rill erosion based upon factors representing climate, soil erodibility, topography, cover, and conservation support practices. The erosion estimate is compared to erosion tolerance values to produce an expression of the current erosion status. An index of inherent site erodibility is also achieved through manipulation of the USLE. Based on published soil surveys, satellite imagery, and ground-truth vegetation transects, data layers are created within GRASS for each of the component factors of the USLE. Appropriate mathematical operations are performed with the data layers, and color-coded maps are produced that represent the erosion status and erodibility index for each 50-m × 50-m area of soil surface. These maps aid military trainers and land managers in scheduling appropriate kinds and intensities of military training activities. 相似文献
246.
247.
Ecology matters: sustainable development in Southeast Asia 总被引:1,自引:1,他引:0
Victor R. Savage 《Sustainability Science》2006,1(1):37-63
248.
Martin Claussen Victor Brovkin Andrey Ganopolski Claudia Kubatzki Vladimir Petoukhov Stefan Rahmstorf 《Environmental Modeling and Assessment》1999,4(4):209-216
We present a new reduced-form model for climate system analysis. This model, called CLIMBER-2 (for CLIMate and BiosphERe, level 2), fills the current gap between simple, highly parameterized climate models and computationally expensive coupled models of global atmospheric and oceanic circulation. We outline the basic assumptions implicit in CLIMBER-2 and we present examples of climate system analysis including a study of atmosphere–ocean interaction during the last glacial maximum, an analysis of synergism between various components of the climate system during the mid-Holocene around 6000 years ago, and a transient simulation of climate change during the last 8000 years. These studies demonstrate the feasibility of a computationally efficient analysis of climate system dynamics which is a prerequisite for future climate impact research and, more generally, Earth system analysis, i.e., the analysis of feedbacks between our environment and human activities. 相似文献
249.
Yuri Gorokhovich Reza Khanbilvardi Lorraine Janus Victor Goldsmith David Stern 《Journal of the American Water Resources Association》2000,36(3):523-539
ABSTRACT: The purpose of this paper is to present a new approach for the spatially distributed modeling of water flow during storm events. Distributed modeling of flow during storm events is an important basis for any environmental modeling, including turbidity or sediment transport. During the initial phase of a rainstorm, surface runoff is the main contributor of flow. To provide the spatial components for distributed hydrological modeling a Geographic Information System (GIS) was used to map and visualize contributing areas around a stream channel. Stream segments were defined using the hydrologic response unit (HRU) concept. Lateral flows were derived from GIS output for each segment of the stream and at each time interval of the rain storm and were routed using the kinematic routing equation. This approach is new in hydrological modeling and can be used to enhance many existing simulations. The model is also unique in the fine time scale (i.e., intervals are on the order of minutes). Model results showed good correlation with measured discharge values; however, further studies of contributing area behavior, its relationship with soil types and slope categories, and the influence of watershed size are needed to improve model performance. This model will be used in the future as the basis to model turbidity in streams. 相似文献
250.
A stakeholder driven process to reduce vulnerability to climate change in Hermosillo,Sonora, Mexico 总被引:1,自引:0,他引:1
Hallie Eakin Victor Magaña Joel Smith José Luis Moreno José Maria Martínez Osvaldo Landavazo 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):935-955
While there is a growing body of knowledge on potential impacts of climate change on water availability, there has been much
less empirical research on exploring the viability of particular adaptation options. The participation of stakeholders in
defining appropriate adaptation strategies is increasingly recognized as a critical element in the translation of climate
change impact research into effective actions to reduce future vulnerability, yet the process by which stakeholders are included
in such initiatives is not well-defined. This article presents the results of a pilot project in which a participatory approach
was employed to identify and evaluate adaptation options to climate change scenarios for Sonora’s capital city, Hermosillo.
In an iterative process, stakeholders representing different water users and managers in the city met to discuss climate change
scenarios, identify specific adaptation options, and evaluate a subset of options for possible future implementation. This
process enabled the focus of the investigation on those adaptations that addressed not only concerns with the potential future
impacts of climate change but also the immediate and pressing concerns about development patterns and water use in the city.
Two of the adaptations to climate change identified by stakeholders would also reduce energy demand. The simplicity of the
approach makes it a feasible model for adaptation initiatives in other regions of Mexico and in other countries in Latin America.
相似文献
Osvaldo LandavazoEmail: |