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991.
We describe a 2-year-old boy with chondrodysplasia punctata (CDP). The boy was exposed to phenytoin, in combination with carbamazepine, during pregnancy. There has been previous evidence for a connection between phenytoin exposure during pregnancy and chondrodysplasia punctata. The boy had clinical and some radiological characteristic features of CDP, of the tibia-metacarpal type. We know of no other report on a child exposed to phenytoin during pregnancy who developed CDP of this type. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
992.
Phase space prediction is a feature selection method which triesto exploit non-linear dynamics of an underlying system. We describe and offer a critical reconsideration of this approach,discuss questions of whether non-linear methods are justified by the data, and apply them to ozone time series from single locations. Our main objectives are to obtain air quality forecasts in order to provide public health warnings and to provide an insight into the dynamics of the underlying system.Interestingly, comparable linear data sets (surrogates)have very similar structure and give similar predictionaccuracy to that of the ozone data. In this instance theredoes not appear to be any advantage to applying the phasespace approach to univariate time series. 相似文献
993.
994.
Journal of Material Cycles and Waste Management - In this study, 1, 2, and 3% micronized aluminum powder were used by replacing with fly ash to improve the properties of F class fly ash-based... 相似文献
995.
A. B. Attygalle O. Vostrowsky H. J. Bestmann S. Steghaus-Kovac U. Maschwitz 《Die Naturwissenschaften》1988,75(6):315-317
We wish to thank Prof. V. Schurig (Tübingen) for lending us the columns for preliminary studies, and Prof. K. Mori (Tokyo), N. Frighetto and R. T. S. Frighetto (Erlangen) for optically active samples of 4-methyl-3-heptanol. This work was supported by the Deutsche Forschungsgemeinschaft. 相似文献
996.
Phenolic xenoestrogens in surface water, sediments, and sewage sludge from Baden-Württemberg, south-west Germany. 总被引:1,自引:0,他引:1
Nine structurally different phenolic chemicals, which have been reported to mimic estrogen effects, were determined in various aquatic environmental compartments. Twenty-three water samples from five streams and rivers showed levels up to 458 ng/l for 4-nonylphenol (4NP), 189 ng/l for 4-t-octylphenol (4tOP), 272 ng/l for bisphenol A (BPA) and 47 ng/l for 2-hydroxybiphenyl (2OHBiP). Elevated levels of these compounds in a stream with a high load of effluents of sewage treatment plants (STPs), compared to a brook free of sewage, identified STPs as major sources. With a similar order, 4NP (10-259 micrograms/kg dry matter), 4tOP (< 0.5-8 micrograms/kg), BPA (< 0.5-15 micrograms/kg), and 2OHBiP (2-69 micrograms/kg) were also detected regularly in riverine sediment (n = 11). Levels in sewage sludge were one order of magnitude higher than in sediments. 4-Hydroxybiphenyl and 4-chloro-3-methylphenol were found predominantly in sludge and sediment in the lower ppb range. 相似文献
997.
998.
Joanna Endter‐Wada Judith Kurtzman Sean P. Keenan Roger K. Kjelgren Christopher M.U. Neale 《Journal of the American Water Resources Association》2008,44(4):902-920
Abstract: Landscape water conservation is an important issue for municipalities throughout the Western United States, and especially in Utah as rapid growth strains existing water supplies. We conducted interdisciplinary research in Layton, Utah, that aimed at understanding patterns of landscape water use among households and businesses. The research project involved three basic tasks. First, a landscape “water budget” was developed by producing a calibrated and classified mosaic of landscape type and area from airborne multispectral digital imagery, integrating this information with Layton City parcel boundary data to determine landscape vegetated areas per lot, and estimating irrigation needs derived from reference evapotranspiration (ETo) obtained using weather data for the Salt Lake City metropolitan region. Second, utilizing Layton water billing data, water use for each household and business was identified and categorized as “conserving,”“acceptable” or “wasteful” by determining how much the water applied varied from actual landscape plant need. Third, surveys were administered to a random stratified sample of households and businesses in the study area to investigate various factors that were hypothesized to be predictive of wasteful watering practices. This paper primarily focuses on analysis of the household and business survey data, which explores factors affecting urban landscape water use from a human behavioral perspective. We found that the most significant factors predicting actual water use were the type of irrigation system and whether the location was a household or business. Attitudinal and motivational characteristics were not consistently associated with water use. We found that wasteful watering is the result of many factors embedded in the complex context of urban landscapes. This implies that water conservation programs should identify potential wasteful users through analyses of water billing data and direct water conservation measures at these users by focusing on site‐specific evaluations and recommendations. Water audits or water checks are one such tool that some communities have employed to help people understand and assess the quantity of water needed by and applied to their landscapes. This approach provides an opportunity to evaluate situational constraints at particular locations and design appropriate strategies for reducing water waste. 相似文献
999.
No evidence for the work-conflict hypothesis in the eusocial naked mole-rat (Heterocephalus glaber ) 总被引:1,自引:0,他引:1
The work-conflict hypothesis (Reeve 1992) postulates that in eusocial naked mole-rat (Heterocephalus glaber) colonies there is potential conflict between the breeding female and her non-breeding colony mates over how much aid they
provide in support of her reproduction. Non-breeders may withhold aid either because they are hopeful reproductives and/or
because they have less to gain in terms of inclusive fitness. Breeding females should, therefore, preferentially direct aggression
in the form of shoving (prolonged pushes usually involving nose-to-nose contact) towards large (hopeful reproductives) and
less related non-breeders to incite them to provide aid. This study tested the following predictions of the work-conflict
hypotheses. (1) There is kin bias in the shove rate of breeding females and work rates of non-breeders; (2) Shoving activates
work in non-breeders. We found no evidence to suggest that the breeding female shove rate and the amount of colony maintenance
activities performed by non-breeders is influenced by relatedness. Body size was a better predictor of work rate and shove
rate; large animals were shoved more and worked less. Furthermore, shoving did not affect the work rate of non-breeders and
rarely incited activity in inactive mole-rats. Individual mole-rats were also more likely to be shoved when already active
than when resting in the nest. These results suggest that shoving by the breeding female may have functions other than the
incitement of activity, such as the reproductive suppression of non-breeders.
Received: 17 January 1996 / Accepted after revision: 21 September 1996 相似文献
1000.