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71.
Deployment in a crisis zone is a perilous undertaking. Little is known right now about how humanitarian workers relate social and professional goals to lived experiences of high-risk environments. In South Sudan, ranked as the most dangerous country globally for aid workers, 20 international humanitarian staff were interviewed to examine their sense of place, well-being, and vocation, using thematic and interpretative phenomenological analysis. Subjectivities of humanitarian space hinged upon negotiating physical hardships and social relationships: Juba, the capital, was described as a ‘prison’ and a ‘party hotspot’. For expatriate staff, making sense of spatial, social, and professional transience was sharply gendered and rooted in the subjectivities of risk-taking, crisis management, and career-building. Two policy measures are highlighted here to address the implications of transience for human well-being and organisational effectiveness. Efforts to support teams and structure work environments, altering the humanitarian and vocational bubble, will help to develop resilience at the heart of humanitarian systems.  相似文献   
72.
Global Positioning System (GPS) collars are increasingly used to study animal movement and habitat use. Measurement error is defined as the difference between the observed and true value being measured. In GPS data measurement error is referred to as location error and leads to misclassification of observed locations into habitat types. This is particularily true when studying habitats of small spatial extent with large amounts of edge, such as linear features (e.g. roads and seismic lines). However, no consistent framework exists to address the effect of measurement error on habitat classification of observed locations and resulting biological inference. We developed a mechanistic, empirically-based method for buffering linear features that minimizes the underestimation of animal use introduced by GPS measurement error. To do this we quantified the distribution of measurement error and derived an explicit formula for buffer radius which incorporated the error distribution, the width of the linear feature, and a predefined amount of acceptable type I error in location classification. In our empirical study we found the GPS measurement error of the Lotek GPS_3300 collar followed a bivariate Laplace distribution with parameter ρ = 0.1123. When we applied our method to a simulated landscape, type I error was reduced by 57%. This study highlights the need to address the effect of GPS measurement error in animal location classification, particularily for habitats of small spatial extent.  相似文献   
73.
AVHRR草地分类的潜力和局限:以锡林郭勒草原为例   总被引:9,自引:0,他引:9  
AVHRR-NDVI已广泛应用于宏观土地覆盖研究,但在区域研究中应用比较少。论文根据1999年锡林郭勒草原4种草地NDVI的动态过程,结合对应AVHRR提供的额外信息,对4种草地进行了分类。首先,根据全年NDVI低平的特点检测出荒漠;第二,使用6月Ch3>3180和Ch5>3100区分出沙地草地;第三,使用8月Ch2>200或6~8月NDVI6~8月>1.2检测出长势良好的草甸。与基于TM的草地图比较,AVHRR的分类结果失去了许多细节,但对土地覆盖长期变化研究仍有价值,特别是对沙漠化过程的监测。需要进一步的研究才能确定AVHRR在区分长势差的草甸和典型草原方面的潜力或局限。  相似文献   
74.
The petrochemical and petroleum industries are two of the main sources of industrial air pollution in Taiwan. Data used in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to oil refinery plants. The prevalence of delivery of preterm birth infants was significantly higher in mothers living near the oil refinery plants than in control mothers in Taiwan. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.14 (95% CI=1.01-1.28) for delivery of preterm infants for mothers living near oil refinery plants. These data provide further support for the hypothesis that air pollution can affect the outcome of pregnancies.  相似文献   
75.
Fungiacyathus marenzelleri (Vaughan, 1906) is a deep-water solitary coral, cosmopolitan in distribution that is found at depths of 300–6,328 m. This study examined gametogenesis, inter-annual variability and reproductive periodicity of F. marenzelleri collected from Station M (34°50′N, 123°00′W) in the northeast Pacific at a depth of 4,100 m. Samples were collected (May, June, October 1996; August 1998; February, June 2001; and June 2002) and histologically processed with spermatogenic stage, oocyte size and fecundity measured. Four stages of spermatogenesis were identified and all males contained multiple stages of sperm development in each seasonal sample. Three stages of oocyte development were identified; previtellogenic (<28–150 μm), vitellogenic (150–300 μm) and late vitellogenic (300–400 μm). Comparison of mean oocyte diameters among sampling dates showed there were no inter-annual variations or seasonal differences. Overall, fecundity was 1,290 (±407) oocytes polyp−1, and with no significant differences between sample months. Fecundity was not polyp-size dependent. This study shows a similar quasi-continuous mode of reproduction to this species examined from the Northeast Atlantic Ocean, but the fecundity is reduced by 50%. The reproductive output may fluctuate in relation to the input of organic material at this site, as shown by non-significant trends in the oocyte size-frequency and fecundity data. A quasi-continuous output of gametes would promote successful fertilisation and wide dispersal of the lecithotrophic larvae.  相似文献   
76.
以橙黄II染料溶液为研究对象,通过正交实验确定了Fe-NTA/H2O2构成的类Fenton反应中各影响因子的最佳操作条件为:[H2O2]=20 mmol/L,[Fe-NTA]=2.5 mmol/L,pH=3。同时考察了反应时间、溶液pH值、H2O2浓度、Fe-NTA浓度对脱色效率的影响。实验表明脱色反应在30 m in内基本完成,类Fenton试剂能在较宽的pH范围内保持较好的脱色效果,而且在pH=6时,类Fenton试剂比传统Fenton试剂的脱色效率提高约75%。增加双氧水浓度可以提高橙黄II溶液脱色率,但超过20 mmol/L后效果提高不明显。在0.5~2.5 mmol/L的范围内,Fe-NTA浓度对脱色效果的影响不显著。  相似文献   
77.
Most of the oyster mariculture beds in Taiwan are in areas located along the west of the island. One of these areas is the Charting coast, where green oysters were found in 1986. During this incident, which became internationally notorious, mass mortality occurred in the Charting oyster beds. After this discovery, measures were taken by the authorities to counter pollution which lead to the problem. The effectiveness of these pollution control actions was evaluated in this study. Two water column indicators, particulate and sediment, and oysters were sampled and analyzed for metals (Cu, Zn, Pb, Ni) in Charting and its neighboring areas, Kuen-Shen Lake and Shin-Da Harbor, and the control area/station, Dah-Pen Wan. The current study shows that copper and zinc concentrations in both oysters and particulates significantly decreased in the Charting area, compared with concentrations found during the period of the green oyster incident. Six years after the incident, the copper concentration in oysters had fallen from a high of 4400 μg/g dry weight to an average of 300±69 μg/g dry weight, figures similar to the copper concentration in 1982. The pollution control actions taken after the incident are believed to be the cause of this recovery of the coastal environment. Nevertheless, Charting still produced oysters with the highest copper and zinc concentrations among the areas investigated. Further measures currently being taken by the government, including removing the sediment of some portions of Erhjin Chi, should be able to bring the oyster copper concentrations down to the levels similar to those observed in the neighboring area, (average concentration below 200 μg/g dry weight or all time maximum concentration below 500 μg/g dry weight).  相似文献   
78.
介绍了以VB6 .0为开发环境 ,运用ActiveXAutomation提供的接口进行AutoCAD的二次开发 ,重点阐述了用VB来开发AutoCAD轮胎模排字系统的算法和步骤 ,并给出了部分代码和例证 ,实践应用效果良好  相似文献   
79.
为了探究贵州煤层高瓦斯低渗透难抽采的原因,以其细观特征为切入点,以贵州富煤区4个高瓦斯低渗透难抽采煤层为研究对象,就煤样的孔隙度、孔径大小、比表面积及孔的连通性等参数对煤层的细观特征进行了分析,分析结果表明:(1)4个试验煤样孔隙度较大,有利于瓦斯的赋存,瓦斯大部分储存在粒间的孔隙内;(2)微孔主要以半封闭孔和封闭孔为主且连通性较差不利于瓦斯的解吸和扩散;(3)煤的微孔比表面积较大,相应的a值也相对较大;煤的微孔孔体积较大,相应的b值也较大。  相似文献   
80.
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