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101.
An interval-parameter fuzzy-stochastic semi-infinite mixed-integer linear programming (IFSSIP) method is developed for waste
management under uncertainties. The IFSSIP method integrates the fuzzy programming, chance-constrained programming, integer
programming and interval semi-infinite programming within a general optimization framework. The model is applied to a waste
management system with three disposal facilities, three municipalities, and three periods. Compared with the previous methods,
IFSSIP have two major advantages. One is that it can help generate solutions for the stable ranges of the decision variables
and objective function value under fuzzy satisfaction degree and different levels of probability of violating constraints,
which are informative and flexible for solution users to interpret/justify. The other is that IFSSIP can not only handle uncertainties
through constructing fuzzy and random parameter, but also reflect dynamic features of the system conditions through interval
function of time over the planning horizon. By comparing IFSSIP with interval-parameter mixed-integer linear semi-infinite
programming and parametric programming, the IFSSIP method is more reasonable than others. 相似文献
102.
Kotzerke A Sharma S Schauss K Heuer H Thiele-Bruhn S Smalla K Wilke BM Schloter M 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):315-322
Most veterinary drugs enter the environment via manure application. However, it is unclear how these substances interact with soil biota. Therefore, it was the aim of the present study to investigate the effects of manure containing different concentrations of the antibiotic sulfadiazine (SDZ) on the soil microbial communities. It was shown that manure alone has a stimulating effect on microbial activity. Only potential nitrification was negatively influenced by manure application. The addition of SDZ to the manure reduced microbial activity. Depending on the SDZ concentration, levels of activity were in the range of the control soil without manure application. Also, selected processes in nitrogen turnover were negatively influenced by the addition of SDZ to the manure, with nitrification being the only exception. The effects were visible for up to 4 days after application of the manure with or without SDZ and were correlated with the bioavailability of the antibiotic. 相似文献
103.
Evaluation of stream ecological integrity using litter decomposition and benthic invertebrates 总被引:1,自引:0,他引:1
Biomonitoring programs to access the ecological integrity of freshwaters tend to rely exclusively on structural parameters. Here we evaluated stream ecological integrity using (a) benthic macroinvertebrate derived metrics and a biotic index as measures of structural integrity and (b) oak litter decomposition and associated fungal sporulation rates as measures of functional integrity. The study was done at four sites (S1, S2, S3 and S4) along a downstream increasing phosphorus and habitat degradation gradient in a small stream. The biotic index, invertebrate metrics, invertebrate and fungal communities' structure and sporulation rates discriminated upstream and downstream sites. Decomposition rates classified sites S4 and S2 as having a compromised ecosystem functioning. Although both functional and structural approaches gave the same results for the most impacted site (S4), they were complementary for moderately impacted sites (S2 and S3), and we therefore support the need for incorporating functional measures in evaluations of stream ecological integrity. 相似文献
104.
苏州河的功能定位与综合整治目标 总被引:3,自引:2,他引:3
苏州河水“变情”,是上海人民长期以来的一个美好愿望。根据市委、市府确定的苏州河环境综合整治目标,该文论述了苏州河环境综合整治总体规划方案的基本思想,提出苏州河的功能定位要从实际出发,并全面考虑迈向21世纪的上海城市发展需要,使苏州河综合整治成为上海环境建设的标志性工程。 相似文献
105.
Gordon Nigh 《Environmental management》1998,22(2):197-202
/ British Columbia has an ecosystem classification system that classifies sites into site series. Foresters commonly measure the productivity of these sites by their site index. In British Columbia, site index is defined as the height of a stand at breast height age 50 and is usually estimated from height-age models. Biogeoclimatic site series/site index relationships are an increasingly popular method of estimating site index in British Columbia for stands where site index cannot be reliably estimated with height-age models. The precision of the predicted site index from these relationships can be evaluated with prediction intervals. This is done for the predicted site index of a single site, a group of sites, or the areally weighted site index of a group of sites. The methodology is also useful in determining the number of sites required to meet a specified precision. These prediction intervals will assist foresters in making sound forest management decisions.KEY WORDS: Biogeoclimatic Ecosystem Classification; Precision; Prediction interval; Site index; Site series 相似文献
106.
Amber J. Soja Herman H. Shugart Anatoly Sukhinin Susan Conard Paul W. Stackhouse Jr. 《Mitigation and Adaptation Strategies for Global Change》2006,11(1):75-96
Under current climate change scenarios, temperatures in Siberia are expected to increase, and consequently, fire is also expected
to increase. Potential climate-induced change is difficult to assess in Siberia because ground-based fire data are not complete.
This investigation introduces a method by which potential climate-induced change can be remotely evaluated. Mean fire return
intervals are established for 58 ecosystems across Siberia using eight years of satellite-based area burned data (1995 to
2002). Mean fire return intervals should decrease under current climate change scenarios, however the results do not currently
demonstrate consistent evidence of fire-induced change. The overall boreal forest mean fire return interval is lower than
the published mean, inferring increased fire. Most notably, using satellite data to calculate mean fire return intervals in
individual ecosystems for the entire population of fire is shown to be a viable method by which potential climate-induced
land cover change can be evaluated. 相似文献
107.
对于非等时序列的时数分离可以建立模型,但这种模型误差分析较困难。本文在残差GM(1,1)模型的基础上,建立了时数分离残差模型,对误差进行修正。应用这种模型分析了德兴铜矿1#尾矿坝的渗流趋势,结果表明,模型能够大大提高预测精度,满足工程预测的需要。 相似文献
108.
109.
考察了不同有机改性硅对微囊藻毒素LR(mLR)和LA(mLA)的等温吸附行为。结果表明,有机改性硅可有效吸附去除水体中<0.1×10-6(质量分数)的微囊藻毒素,并且吸附去除效果随表面改性官能团中碳原子数量的增加而增加;相同条件下,有机改性硅在微囊藻毒素异构体之间存在着一定的吸附选择性。 相似文献
110.
Adaptive two-stage one-per-stratum sampling 总被引:1,自引:0,他引:1
Mary C. Christman 《Environmental and Ecological Statistics》2003,10(1):43-60
We briefly describe adaptive cluster sampling designs in which the initial sample is taken according to a Markov chain one-per-stratum design (Breidt, 1995) and one or more secondary samples are taken within strata if units in the initial sample satisfy a given condition C. An empirical study of the behavior of the estimation procedure is conducted for three small artificial populations for which adaptive sampling is appropriate. The specific sampling strategy used in the empirical study was a single random-start systematic sample with predefined systematic samples within strata when the initially sampled unit in that stratum satisfies C. The bias of the Horvitz-Thompson estimator for this design is usually very small when adaptive sampling is conducted in a population for which it is suited. In addition, we compare the behavior of several alternative estimators of the standard error of the Horvitz-Thompson estimator of the population total. The best estimator of the standard error is population-dependent but it is not unreasonable to use the Horvitz-Thompson estimator of the variance. Unfortunately, the distribution of the estimator is highly skewed hence the usual approach of constructing confidence intervals assuming normality cannot be used here. 相似文献