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741.
This article shows the results of research on psychosocial risks for a group of machine and plant operators (n?=?1014) from the construction, chemical, energy, mining, metal and food industries in Poland. The Psychosocial Risk Scale designed in Nofer Institute of Occupational Medicine (NIOM) by Moscicka-Teske and Potocka was used to indicate the occurrence of general and specific occupational stressors and the level of their stressfulness. The results revealed that the studied machine and plant operators experience job context stress – related to working environment features concerning work organization – more frequently than job content stressors – related to the type of tasks they perform. Moreover, a correlation analysis between work features and the health and occupational functioning of the respondents revealed significant but weak relationships between the variables (from ?0.08 to ?0.23). Comparative analysis revealed the differences between the studied sectors. Such a comparison makes it possible to set goals for each sector and to attempt to improve the distinctive areas.  相似文献   
742.
The aim of the present study was to estimate spillover effects between the work and the family sphere in a sample of nurses (N = 2058). Hierarchical regression analyses investigated whether shift work schedules were associated with negative or positive spillover, both from family to work and vice versa, controlling for demographic factors, job demands and decision latitude. With daytime work as a reference group, all types of shift work (day and evening shift, night shift only and rotating 3 shift) were associated with higher negative work-to-family spillover. Night work was associated with significantly less negative family-to-work spillover. None of the different shift work schedules were related to any type of positive spillover. The results indicate that working outside of daytime hours is less compatible with workers’ family lives, compared to working ordinary day shifts. On the other hand, working night shifts only was associated with reduced negative family-to-work spillover.  相似文献   
743.
为了分析裴沟矿31采区的煤炭开采对上部魔洞王水库的影响,以及评价水体下开采的安全性,首先分析了岩土体材料在三轴压缩试验中表现出来的应变软化现象,认为岩石峰后的软化能够说明覆岩破坏后的力学特性;然后介绍了FLAC3D中应变软化模型;最后分别建立Mohr—Coulomb理想弹性模型和应变软化模型的数值模型,针对工作面推进过程中覆岩移动破坏的特征以及顶板导水裂隙带发育规律,分析了两者计算结果的差别,计算结果表明:应变软化模型对覆岩移动破坏特征的计算更加准确,能够说明工作面推进过程中覆岩移动规律,通过其计算得到的导水裂隙带高度的预计对水体下采煤的安全性评价有一定的参考价值。  相似文献   
744.
Previous research on the job demand–control–support (JDCS) model of occupational stress has generally been inconsistent at best regarding a key issue: the interaction of demands, control, and support in predicting employee health and well‐being. However, the model continues to be tested in a variety of studies and academic journals owing to its intuitive appeal. By incorporating conservation of resources theory with knowledge from the challenge–hindrance stressor framework, we proposed that hindrance stressors, not the challenge stressors commonly assessed when testing JDCS theory, will provide validation for the model. A two‐wave panel study of 228 employees in a variety of occupations provided support for three‐way interactions between hindrance demands, control, and support predicting job‐related anxiety and physical symptoms. Three‐way interactions using a challenge demand (forms of workload) were not significant, consistent with our propositions. In summary, this study supports the buffering effect of control and support on the relationship between job demands and strain only when job demands reflect hindrance stressors, thereby proposing to alter the JDCS model by specifying that it applies primarily to hindrance stressors in a job hindrance–control–support model. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
745.
A bacterium classified as Achromobacter xylosoxidans strain IR08 by phenotypic typing coupled with 16S rRNA gene analysis wasisolated from a soil contaminated with electrical transformer fluid for over sixty years using Aroclor 1221 as an enrichment substrate.The substrate utilization profiles revealed that IR08 could grow on all three monochlorobiphenyls (CBs), 2,4'- and 4,4'-dichlorobiphenylas well as 2-chlorobenzoate (2-CBA), 3-CBA, 4-CBA, and 2,3-dichlorobenzoate. Unusually, growth was poorly sustained on biphenyland benzoate. In growth experiments, IR08 degraded all CBs (0.27 mmol/L) in less than 96 h with concomitant stoichiometric release ofinorganic chloride and growth yields were 2-3 times higher than those observed on biphenyl. In contrast to most of the chlorobiphenyl-degrading strains described in the literature, which are reported to form CBA, no metabolite was identified in the culture broth byHPLC analysis. When co-incubated with respective CBs and biphenyl, strain IR08 preferentially utilized the chlorinated analoguesin less than 96 h while it took another 264 h before 90% of the initially supplied biphenyl could be degraded. The promotion of co-metabolic transformation of halogenated substrates by the inclusion of their non-halogenated derivatives may not therefore, result inuniversal benefits.  相似文献   
746.
为提高大型货物运输通道选择科学性,通过分析大型货物运输影响因素,建立大型货物运输通道选择指标评价体系,采用PCA法改进层次分析法,构建多目标大型货物运输通道选择决策模型,有效避免决策目标间信息重复利用。结果表明:优化后的决策模型可有效避免建模过程中对决策目标间信息重复利用,为大型货物运输通道线路方案决策提供依据。  相似文献   
747.
为研究不同坡度隧道在大功率火源情况下的烟气运动,采用1∶20的缩尺隧道模型,通过试验对不同坡度情况下(-6%,-3%,0%,3%,6%)的大火源功率火灾(20,50 MW)时的隧道纵向通风临界风速进行研究。结果表明:0%坡度时,20 MW和50 MW的临界风速相差不大;有坡度时,逆坡送风的临界风速大于顺坡送风的临界风速。根据试验结果拟合得出大火源功率(20,50 MW)条件下坡度为-6%至6%时的临界风速与坡度的关系,并对前人提出的坡度与临界风速的关系式进行修正。  相似文献   
748.
为整体评价大型商圈的安全性,结合公共安全科技三角形理论,从突发事件的危险性、承灾载体的脆弱性、应急能力3方面构建大型商圈安全评价指标体系,通过网络分析法和模糊综合评价法确定指标间权重系数,对大型商圈进行安全风险评价。结果表明:体系全面考虑了大型商圈安全风险影响因素及其内在关系,可为大型商圈安全评价体系构建和定量评估提供参考。  相似文献   
749.
光纤布拉格光栅传感器在钢架结构健康监测中的应用研究   总被引:1,自引:0,他引:1  
光纤布拉格光栅(FBG)传感器凭借其体积小、灵敏度高、耐腐蚀、抗电磁干扰、分布或者准分布式测量、可实现远距离的监测与传输等优点,在土木工程健康监测中得到日益广泛的应用。本文在光纤布拉格光栅(FBG)传感器的传感原理、标定试验研究基础上,讨论了利用FBG传感系统监测钢架结构在冲击荷载作用下的应变和加速度的可行性;同时利用ANSYS有限元分析软件建立了适用于结构分析的有限元模型,对钢架结构进行了详细的仿真分析计算,最后对理论计算结果及实测结果进行了详细的对比分析,所取得的结果比较接近。研究表明,光纤布拉格光栅传感器可以很好的测量钢架结构的动态响应。  相似文献   
750.
为预测大落差管道局部高点水击压力,避免在关阀、停泵等应急操作过程中因高点低压而使油品气化,采用OLGA软件水击计算模块分析介质流速、高点稳态压力、关阀时间、阀门位置对高点水击压力的影响机制,并结合国内某原油管道现场SCADA系统数据进行验证;采用通用全局优化算法(UGO)和列文伯格-马夸尔特法(LM)建立局部高点压力预测方程,相对误差在5%以内。研究结果表明:本文方程可实现大落差输油管道水击过程中局部高点水击压力的预测。研究结果可为大落差输油管道安全运行与管理提供参考。  相似文献   
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