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排序方式: 共有803条查询结果,搜索用时 31 毫秒
51.
52.
Compliance and Emissions Trading under the Kyoto Protocol: Rules for Uncertain Inventories 总被引:1,自引:0,他引:1
Zbigniew Nahorski Joanna Horabik Matthias Jonas 《Water, Air, & Soil Pollution: Focus》2007,7(4-5):539-558
A solution is proposed for proving compliance with emission targets and for emissions trading in the event of uncertainties
in reported emission inventories. The solution is based on the undershooting concept, from which the mathematical conditions
for both proving compliance with a risk α and calculating effective emissions for trading are derived. Based on the reported emission units, the number of permits
granted is reduced in proportion to the uncertainty in the inventory. A country whose inventory has higher uncertainty is
thereby allotted fewer permits than a country with the same inventory but smaller uncertainty. 相似文献
53.
山东省的干旱化特征分析 总被引:6,自引:0,他引:6
利用山东省近50多年的农业旱灾灾情资料和降水资料,分析了干旱灾情和致灾因子的变化特征。结果指出:20世纪70年代后期以来,6—9月份西太平洋副高脊线位置偏南,山东省的汛期降水量有明显的减少趋势,导致干旱灾害的受灾面积明显增大。进入90年代以后,与1961—1976年相比,干燥度指数普遍增大,半岛东部及黄河以北地区干燥程度增大得最为明显,半岛东部、鲁东南及鲁南的大部分地区由湿润区演变成了半湿润区,而黄河以北绝大部分地区及鲁中北部、半岛西北部的局部地区则由半湿润区演变成了半干旱地区。造成干燥度变化的主要原因是降水量的变化,其次是积温的变化。 相似文献
54.
55.
长时间单调模拟驾驶对疲劳的影响研究 总被引:7,自引:1,他引:7
通过模拟驾驶实验,综合评估长时间驾驶以及单调环境对驾驶员疲劳程度的影响是笔者研究的主要课题内容。借助于在模拟驾驶座舱上,4个健康样本分别参加高速公路(单调环境)和一般公路(非单调环境)的两组驾驶仿真实验,每组测试均持续两小时,一共进行10次实验。实验过程中,样本的操控数据(车速和方向盘转角)、反应时间、心电信号、主观疲劳状况等都同步记录并保存。实验结果表明长时间驾驶对操控能力、反应时间、心率、主观疲劳都有显著性影响(p<0.050),单调环境(高速公路)和非单调环境(一般公路)相比,车速方差区别显著,而尽管被试在高速公路的单调环境下驾驶后主观感觉更疲劳一些,但反应时间、心率等因素并没有显著性差异。 相似文献
56.
现阶段为了适应国际及国内防火形势,出现了以水灭火为主要形式的灭火方式,并且在实际灭火中体现出巨大的优势.其中泵串联水灭火就是一种很好的形式.林海集团设计了一套远距离接力水泵串联供水灭火系统,尝试以手抬水泵(消防泵)接力供水的方式,从有水源的地方经过消防泵的增压,通过消防水带输送到火场,为水灭火工作提供条件,以实现水灭火. 相似文献
57.
58.
Thomas P. Wagner Leonard Ortolano 《Journal of the American Water Resources Association》1975,11(2):329-344
ABSTRACT: The growing demands by the public for a more active role in planning have recently generated considerable interest among researchers and planners in the subject of public involvement techniques. Numerous surveys have found that standard public participation techniques (e.g., public hearings) by themselves are considered inadequate. Several techniques that have potential for overcoming some of the limitations of standard public involvement techniques have recently been developed. This paper describes several of these new techniques and analyzes each of them in terms of their potential utility in water resources planning. 相似文献
59.
ABSTRACT: Landsat radiance values were processed at two different (single and double) levels of accuracy to estimate chlorophyll a, turbidity, and suspended sediment in Lake Okeechobee, Florida. Both ordinary least square and ridge regression analyses were used to establish a relationship between water quality parameters and Landsat radiance. Radiance measurements made at greater precision (double level) gave a better solution in this application. The ridge regression analysis for double level not only can reduce the total mean square error about 13–20 percent and confidence interval about 6–28 percent as compared to ordinary least square analysis, but it can also change the interpretation of analysis results. 相似文献
60.
Evaluating Alternative Temporal Survey Designs for Monitoring Wetland Area and Detecting Changes Over Time in California
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Leila G. Lackey Eric D. Stein 《Journal of the American Water Resources Association》2015,51(2):388-399
Evaluation of wetland extent and changes in extent is a foundation of many wetland monitoring and assessment programs. Probabilistic sampling and mapping provides a cost‐effective alternative to comprehensive mapping for large geographic areas. One unresolved challenge for probabilistic or design‐based approaches is how best to monitor both status (e.g., extent at a single point in time) and trends (e.g., changes in extent over time) within a single monitoring program. Existing wetland status and trends (S&T) monitoring programs employ fixed sampling locations; however, theoretical evaluation and limited implementation in other landscape monitoring areas suggest that alternative designs could increase statistical efficiency and overall accuracy. In particular, designs that employ both fixed and nonfixed sampling locations (alternately termed permanent and temporary samples), termed sampling with partial replacement (SPR), are considered to efficiently and effectively balance monitoring current status with detection of trends. This study utilized simulated sampling to assess the performance of fixed sampling locations, SPR, and strictly nonfixed designs for monitoring wetland S&T over time. Modeled changes in wetland density over time were used as inputs for sampling simulations. In contrast to previous evaluations of SPR, the results of this study support the use of a fixed sampling design and show that SPR may underestimate both S&T. 相似文献