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Nasreen Islam Khan David Bruce Ravi Naidu Gary Owens 《Environmental geochemistry and health》2009,31(Z1):221-238
Dietary intake of water and food has been identified as one of the major pathways for arsenic (As) exposure in the rural population
of Bangladesh. Therefore, realistic assessment and measurement of dietary intake patterns are important for the development
of an accurate estimate of As exposure and human health risk assessment. One important consideration is to identify an appropriate
tool for measuring dietary intake. In this study an interviewer-administered Food Frequency Questionnaire (FFQ) was implemented
to determine age and gender specific dietary intake. The developed FFQ was unique because it developed a synergy between field
dietary assessment and As concentration measurements in various environmental media. The resulting integrated database provided
an accurate framework for the process of As exposure and human health risk assessment. The preliminary results reported here
from the FFQ demonstrated that this technique could be used in rural areas as a tool to assess As exposure and the associated
human health risk. 相似文献
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Robert K Hall Peter Husby Gary Wolinsky Olof Hansen Michiko Mares 《Environmental monitoring and assessment》1998,51(1-2):357-367
The Central Valley of California contains critical habitat for many aquatic and terrestrial biological resources. The purpose of this R-EMAP project was to assess the effects from a highly modified agriculturally dominated landuse area on the aquatic resources of the lower portion of the Central Valley watersheds. The study area is 24,346 mi2 and comprises the Sacramento Valley and San Joaquin Valley watersheds to the 1,000 ft. elevation contour. Populations of interest are man-made conveyances and wadeable natural streams. There are 40,756 miles of streams and constructed conveyances within the Central Valley as designated by RF3 database. Sample sites were selected to represent 14,399 miles of streams and sloughs, and 16,697 miles of constructed conveyances. 相似文献
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Gary C. White 《Environmental and Ecological Statistics》2008,15(1):89-99
Program MARK provides > 65 data types in a common configuration for the estimation of population parameters from mark-encounter
data. Encounter information from live captures, live resightings, and dead recoveries can be incorporated to estimate demographic
parameters. Available estimates include survival (S or ϕ), rate of population change (λ), transition rates between strata (Ψ), emigration and immigration rates, and population
size (N). Although N is the parameter most often desired by biologists, N is one of the most difficult parameters to estimate precisely without bias for a geographically and demographically closed
population. The set of closed population estimation models available in Program MARK incorporate time (t) and behavioral (b) variation, and individual heterogeneity (h) in the estimation of capture and recapture probabilities in a likelihood framework. The full range of models from M
0 (null model with all capture and recapture probabilities equal) to M
tbh
are possible, including the ability to include temporal, group, and individual covariates to model capture and recapture
probabilities. Both the full likelihood formulation of Otis et al. (1978) and the conditional model formulation of Huggins
(1989, 1991) and Alho (1990) are provided in Program MARK, and all of these models are incorporated into the robust design
(Kendall et al. 1995, 1997; Kendall and Nichols 1995) and robust-design multistrata (Hestbeck et al. 1991, Brownie et al.
1993) data types. Model selection is performed with AICc (Burnham and Anderson 2002) and model averaging (Burnham and Anderson
2002) is available in Program MARK to provide estimates of N with standard error that reflect model selection uncertainty. 相似文献
619.
The effects of learning versus outcome distal goals in conjunction with proximal goals were investigated in a laboratory setting using a class‐scheduling task. The participants (n = 96) needed to acquire knowledge in order to perform the task correctly. A ‘do your best’ outcome goal led to higher performance than the assignment of a specific, difficult outcome goal. However, the assignment of a specific, difficult learning goal led to higher performance than urging people to ‘do their best.’ Goal commitment was higher in the learning goal than in the outcome goal condition. The correlation between task‐relevant strategies discovered and performance was positive and significant. The number of task‐relevant strategies implemented by participants assigned a distal learning goal in conjunction with proximal goals was higher than in any other goal condition. Setting a distal outcome or learning goal that included proximal outcome goals, however, did not lead to higher performance than the setting of a distal outcome or learning goal alone. Self‐efficacy correlated significantly with performance, and this effect was mediated through strategy development. Furthermore, the discovery of task‐relevant strategies affected self‐efficacy through an increase in performance. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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