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1.
以某酸性气制硫酸装置酸性气缓冲罐为例,进行外部安全防护距离设计,结合当地多种气象,使用PHAST软件和LEAK软件进行H_2S气体扩散和爆炸计算,扩散结果应用于周边人员集中场所的防毒设计以及企业的应急救援,H_2S爆炸计算结果应用于周边人员集中场所建构筑物的抗爆设计,并和《石油化工工厂布置设计规范》(GB 50984-2014)中的建议值进行比对。 相似文献
2.
《Journal of Great Lakes research》2021,47(5):1305-1315
As sentinels of climate change and other anthropogenic forces, freshwater lakes are experiencing ecosystem disruptions at every level of the food web, beginning with the phytoplankton, a highly responsive group of organisms. Most studies regarding the effects of climate change on phytoplankton focus on a potential scenario in which temperatures continuously increase and droughts intersperse heavy precipitation events. Like much of the conterminous United States in 2019, the Muskegon River watershed (Michigan, USA) experienced record-breaking rainfall accompanied by unusually cool temperatures, affording an opportunity to explore how an alternate potential climate scenario may affect phytoplankton. We conducted biweekly sampling of environmental variables and phytoplankton in Muskegon Lake, a Great Lakes Area of Concern that connects to Lake Michigan. We compared environmental variables in 2019 to the previous eight years using long-term data from the Muskegon Lake Observatory buoy, and annual monitoring excursions provided historical phytoplankton data. Under cold and wet conditions, diatoms were the single dominant division throughout the entire growth season – an unprecedented scenario in Muskegon Lake. In 10 of the 13 biweekly sampling days in 2019, diatoms comprised over 75% of the phytoplankton community in the lake by count, indicating that the spring diatom bloom persisted through the fall. Additionally, phytoplankton seasonal succession and abundance patterns typically seen in this lake were absent. In a world experiencing reduced predictability, increased variability, and regional climate anomalies, studying periods of extreme weather events may offer insight into how natural systems will be affected and respond under future climate scenarios. 相似文献
3.
Kazufumi Nagashima Lembit Sihver Nakahiro Yasuda 《Journal of Nuclear Science and Technology》2019,56(7):629-638
This paper aims at clarifying the potential and the limit of the method to surmise the timing of the containment vessel (CV) failure utilizing the Emergency Action Levels (EALs) issued as a nuclear operator’s notification in an early phase of the severe accident (SA). We analyzed the timings of the EALs issued in all kinds of the SA sequences of several PWR plant models by using the SA analysis code, MAAP. We found high correlations between the timing of SE41 (EAL issued at CV pressure of 0.5 design pressure) and the timing of the CV failure in the typical scenarios, e.g. over-pressure failures. We could therefore establish an evaluating method to estimate the time for a CV failure. This method has the potential to support the decision-making in nuclear emergency preparedness. 相似文献
4.
We conceptualized security-related stress (SRS) and proposed a theoretical model linking SRS, discrete emotions, coping response, and information security policy (ISP) compliance. We used an experience sampling design, wherein 138 professionals completed surveys. We observed that SRS had a positive association with frustration and fatigue, and these negative emotions were associated with neutralization of ISP violations. Additionally, frustration and fatigue make employees more likely to follow through on their rationalizations of ISP violations by decreased ISP compliance. Our findings provide evidence that neutralization is not a completely stable phenomenon but can vary within individuals from one time point to another. 相似文献
5.
Yohannes Eneyew Ayalew 《Information & Communications Technology Law》2019,28(2):208-224
Freedom of expression is a foundational stone for democracy and embraces a number of other rights, including – freedom to seek, receive, and impart information using any medium. Around 16 million Ethiopians, comprising 15.4% of the total population, use the Internet. The Ethiopian Internet shutdown saga has been marked by competing narratives. On one hand, the government has been using two governing narratives, i.e. national security narrative and ‘economic growth’ narrative to justify shutdowns of the Internet. But, the individuals’ self-expressions on social media find itself as competing narrative. Since 2016, the Internet has been closed more than six times under the cloak of national security, quelling rising protests, controlling strikes, and exam cheating. As such, freedom of expression of millions has been muzzled. The article argues blanket Internet shutdowns do not meet the caveats of human rights law. 相似文献
6.
为进一步减少煤矿事故发生后的人员伤亡、财产损失,在分析国内外煤矿井下避难系统发展的基础上,以何家塔煤矿井下避难硐室系统的构建设计与应用为例,详细介绍了井下避难硐室系统的分类、结构构成、功能需求和配套设施等,并通过紧急避险疏散时间的校验计算,提出避难硐室距离采掘工作面以不超过1 000 m为宜,且应按照“地面最安全,先逃生后避险”原则进行避险救援,为国内其他矿井避难硐室的构建应用和相关标准的制定提供了参考。 相似文献
7.
8.
Work teams experience workload from the group dynamics in addition to the usual sources of individual workload. This study had three objectives: to assess the responsiveness of new rating scales for group workload (GWL), investigate their component structure, and determine if changes in workload occur as the team matures. Participants (360 individuals, 44 groups) engaged in an emergency response (ER) simulation in the form of a board game; team size, game difficulty (one versus two opponents), and time constraints were varied. ER teams rated workload after each of two sessions using the NASA Task Load Index (TLX) and GWL. GWL was most responsive to larger task demands and reflected changes in coordination demand over time. Components reflected mixtures of TLX and GWL scales and suggested that self-organising processes were operating. 相似文献
9.
《Ceramics International》2020,46(3):3144-3165
The ceramic nanocomposites (CNCs) like zirconia toughened alumina (ZTA) ceramics are important futuristic materials for structural and functional applications in advanced strategic systems, structural components, biomedical prostheses and devices. In all structural materials including the ZTA CNCs, the very early stages of plastic deformation i.e., the incipient plasticity events (IPE) are most important to be understood so that the microstructure and mechanical properties can be tuned to suit a given end application. Here we report for the first time the mechanisms of IPE in the nanoindentation experiments conducted at 10–1000 mN loads in the 40 ZTA CNCs. Here 40 ZTA CNC stands for 40 vol% of 3 mol% Yttria partially stabilized zirconia toughened alumina (40ZTA) CNC. The role of load ranges in variations of the IPE related parameters in the 40 ZTA CNCs is also studied. Further, an attempt is made to assess how the amount of zirconia content in ZTA CNCs affects the variations of the IPE related parameters. Through the extensive usage of field emission scanning electron microscopy (FESEM) and theoretical estimations, efforts are also directed to check out the linkage, if any, between the localized shear deformation and/or microcracking with the IPE events that occur in the present CNCs. In addition, a new concept of damage resistance is introduced for the first time in the present work to explain the presence of a strong indentation size effect (ISE) in the 40 ZTA CNCs. Finally, an attempt is also directed to understand how the indentation load (P) controls the relative size of interaction zones of dislocation loops as well as the damage resistance and thereby, engineer the acuteness of the ISE in ZTA CNCs. The implication of these findings in futuristic design of especially the ZTA CNCs for various applications is also discussed. 相似文献
10.
近年来,向保健品中非法添加药物的现象时有发生。本研究针对不同保健食品的类别,梳理近年来发生的保健食品非法添加药物事件,对各类保健食品中常可能非法添加的药物及危害进行总结,并且对不同类别的保健食品中非法添加药物的检测技术进行归纳,分析技术的优缺点,为保健食品的市场监管提供参考。 相似文献