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171.
Abstract

What can local case studies contribute to our understanding of the processes underlying the growth in greenhouse gas emissions? Since much abatement and mitigation are local in character, it is important that policy makers identify the mix of local, national and international processes that contribute to changes in greenhouse gas emissions. Drawing upon the results of case studies in Kansas, North Carolina and Ohio, how patterns of emissions in local areas can be connected analytically to the driving forces of environmental change is demonstrated. Emissions at the local level are empirically associated with the same set of trends found at national and international scale, namely, changes in population, affluence‐consumption and technology.  相似文献   
172.
The time-dependent characteristics of the five weather variables which control the annual thermal response of Lake Ohrid are analyzed in detail. These are daily values for solar radiation, air temperature, humidity, wind speed and cloud cover. A simple numerical model of the lake's thermal response, forced by thermally driven density mixing, is developed and tested using observed thermal profiles for verification. The numerical model successfully reproduces the major features of the lake's thermal regime over a 6 y period from 1972 to 1977, the average root mean square value for the simulated profiles being 1.2°C with extremes of 2.2 and 0.3°C and a standard deviation of 0.4°C.  相似文献   
173.
174.
Significant effort has been devoted by past researchers in electrostatic precipitators to electrostatics and particle chemistry. Relatively little, however, has been published on the effect of turbulent flow and its interaction with electrostatics and particle dynamics. This paper describes an experiment and a fundamental model which is focused on the coupled effects of the fluid dynamics and electrostatics.A laboratory precipitator flow facility with laser beam illumination was used to visualize smoke flow. Detailed photographs of flow patterns with and without electric field were recorded in a horizontal plane through the precipitator.A theoretical model was used to numerically simulate the observed flow patterns in the experiment. In the model the flow was described by time-averaged mass and momentum equations with a two-equation turbulence model. The electric field was described by Maxwell electrostatic equation and the continuity of the current equation. The system of the coupled partial differential equations was solved by a finite difference scheme.The interaction between fluid dynamics and electrostatics is shown to have a significant role in altering the flow in the precipitator. The practical implication is that the interaction will aid in particle migration in some regions, but it will increase reentrainment and reduce particle migration in others. Comparison between the results from the experiment and numerical computations shows good qualitative agreement between the two. Since both the electrostatic and the fluid dynamic flow fields depend on the electrode geometry, further investigation may lead to improved design of precipitators.  相似文献   
175.
The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO2 reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO2 storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered?Cthat is the capture of CO2 at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.  相似文献   
176.
Environmental Chemistry Letters - Polyethylene terephthalate is a common plastic in many products such as viscose rayon for clothing, and packaging material in the food and beverage industries....  相似文献   
177.
Environmental Science and Pollution Research - Lentinus crinitus bioaccumulates lithium in mycelia, but bioaccumulation may be affected by pH of the culture medium. Lithium is used in clinical...  相似文献   
178.
Environmental Science and Pollution Research - In this study, lanthanum copper oxide was synthesized under hydrothermal techniques and characterized for doxycycline degradation. The catalyst...  相似文献   
179.
Various iron oxides are used for Fenton reactions to degrade organic pollutants. The degradation efficiency may be improved by transforming an iron oxide phase to another. Here, we report on the transformation of goethite into hematite by thermal treatment at 400 °C. The products were analyzed by X-ray diffractometry, Raman spectroscopy, scanning electron microscopy and N2-physisorption. The catalytic activities were measured for orange II bleaching at initial concentration of 25 mg L?1, pH 3, catalyst concentration of 0.2 g L?1; 5 mM H2O2, 30 °C. Results show that the synthesized goethite was successfully transformed into hematite, and the specific surface area of the material increased from 134 to 163 m2 g?1. The bleaching efficiency of the orange II dye reached 100 % for the hematite product, versus 78 % for goethite. Therefore, a moderate thermal treatment of a plasma-synthesized goethite improves the catalytic oxidation of organic pollutants.  相似文献   
180.
For the antitropical gooseneck barnacle Pollicipes elegans, population-specific physiological temperature tolerance of larvae may serve as a barrier to larval dispersal across the warmest regions of the tropical Pacific Ocean. Thermal tolerance ranges of larvae of three different populations of P. elegans sampled in 2011 and 2012 (Mexico [MX], El Salvador [ES], and Peru [PE]) were investigated by measuring three indicators of physiological performance: swimming activity, oxygen consumption, and lethality or LT50. The thermal tolerance profiles, which include measurable optimum (maximum aerobic performance), pejus (“getting worse”) and pessimum (worst aerobic performance) ranges, of larvae from the three populations were consistent with their characteristic environmental temperatures. In MX, larvae live close to the upper border of their optimum during warm months and so have a limited capacity to tolerate higher-than-normal temperatures. Larvae from the ES population likewise appear to live within their optimum temperature range, but these larvae lack a detectable pessimum range, suggesting they would be unable to cope with temperatures above their pejus range. Larvae from PE have a broad optimum but no pejus range. Different thermal tolerance ranges provide strong evidence for population-dependent physiological adaptations in P. elegans. For the southern (PE) and northern (MX) P. elegans populations, high tropical temperatures are likely to be a strong direct physiological barrier to larval survival and dispersal, which is in contrast to the more thermally tolerant ES population.  相似文献   
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