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191.
There is an increased interest in merging observations from local networks into larger national and international databases. However, the observations from different networks have typically been made using different equipment and applying different post‐processing of the values. These heterogeneities in recorded values between networks can lead to inconsistencies between different networks, and to discontinuities at the borders between regions if the observations are used as a source for interpolated maps of the process. Such discontinuities are undesirable, and could create difficulties in interpreting the maps by decision makers. In this paper, we present two variants of a method that can be used to identify and quantify differences between networks. The first variant deals with networks sharing the same region (usually multiple networks within a country) while the second variant deals with networks in neighbouring regions (usually networks in different countries). The estimated differences can be used to estimate individual biases for each network, which can be subtracted as a harmonization procedure. The method was applied to European gamma dose rate (GDR) measurements from May 2008 from the European Radiological Data Exchange Platform (EURDEP) database. Data from the Slovenian GDR network are used for an application of the first variant of the method whereas the complete dataset is used to illustrate the second variant. The results indicate that these two variants are able to identify and quantify biases reliably, and the interpolated maps after subtraction of the estimated biases appear more reliable than maps created on the basis of the recorded data. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
192.
Some recent research on the properties of the probability density function for the concentration of a scalar dispersing in turbulent flow is summarized. It is concluded that the beta distribution may be a simple model consistent with these properties. This proposal is verified theoretically, and some preliminary data comparisons are very promising. 相似文献
193.
Alan J. Gross 《Environmetrics》1995,6(4):403-412
The United States Environmental Protection Agency (EPA), in its recent risk assessment dealing with environmental tobacco smoke (ETS), estimated the annual number of lung cancer deaths in non-smokers (including both never-smokers and former-smokers who have quit smoking for at least five years) associated with ETS exposure to be between 2500 and 3300 in the United States. This estimate is based on a number of assumptions that are not supported by the existing data. Moreover, the range presented by EPA fails to take into account the uncertainties involved in this estimate. This paper discusses the significant assumptions that underlie any quantitation of lung cancer risks allegedly due to ETS exposure, and explores the uncertainties of each assumption and how each uncertainty affects the summary estimate. The author concludes that any range must encompass an estimate of zero deaths, and that the uncertainties are so great as to cast serious doubt on the use of any quantitative estimate. 相似文献
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E. J. Anthony 《Greenhouse Gases: Science and Technology》2011,1(1):36-47
Calcium looping technology is a promising new technique for high‐temperature scrubbing of CO2 from flue gas and syngases. Current economic projections suggest it might be able to capture CO2 at costs of ∼$20/ton of avoided CO2. Nonetheless there are questions about the long‐term behavior of natural sorbents in such systems, and there is substantial R&D being done on this technology worldwide to answer questions about whether the performance of natural sorbents can be improved, or whether it would be better to use synthetic ones. The current period is particularly interesting as the first pilot plants and demonstration units capable of operating continuously are now coming on stream, and if successful these will lead to large‐scale industrial demonstrations of the technology in the next 10 to 15 years. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
197.
Verhaltensversuche zur Funktion der Lorenzinischen Ampullen 总被引:1,自引:0,他引:1
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Land reclamation techniques that incorporate habitat features for herptofaunal wildlife have received little attention. We
assessed the suitability of a wetland, constructed for the treatment of mine-water drainage, for supporting herptofaunal wildlife
from 1988 through 1990 using diurnal and nocturnal surveys. Natural wetlands within the surrounding watershed were also monitored
for comparison. The treatment wetland supported the greatest abundance and species richness of herptofauna among the sites
surveyed. Abundance was a function of the frog density, particularly green frogs (Rana clamitans) and pickerel frogs (R. palustris), while species richness was due to the number of snake species found. The rich mix of snake species present at the treatment
wetland was believed due to a combination of an abundant frog prey base and an amply supply of den sites in rock debris left
behind from earlier surface-mining activities. Nocturnal surveys of breeding male frogs demonstrated highest breeding activity
at the treatment wetland, particularly for spring peepers (Hyla crucifer). Whole-body assays of green frog and bullfrog (R. catesbeiana) tissues showed no differences among sites in uptake of iron, aluminum, and zinc; managanese levels in samples from the treatment
wetland were significantly lower than those from natural wetlands. These results suggest that wetlands established for water
quality improvement can provide habitat for reptiles and amphibians, with the species composition dependent on the construction
design, the proximity to source populations, and the degree of acidity and heavy-metal concentrations in drainage waters. 相似文献