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1.
Summary Static coating of glass capillary columns has hitherto solely been carried out by evaporation of the stationary phase solvents under vacuum conditions. However, since a solvent vapour pressure higher than the external pressure is the only requirement for the vapour to flow out of the column, evacuation should not be necessary. Several important factors in the static coating procedure, such as mass (solvent vapour) — and heat transfer, heat of vaporisation of the solvent and viscosity of the stationary phase solution at elevated temperature and outlet pressure are discussed, principally to rationalise an improved static coating procedure. The alternative, so-called free-release static coating procedure, was evaluated practically by coating several columns with OV-101 and SE-30. Coating speed was found to be rapid and relatively constant whereas coating efficiency was between 80 and 100%.  相似文献   
2.
The first objective data showing the geographical locations of people in Fukushima after the Fukushima Dai-ichi nuclear power plant accident, obtained by an analysis of GPS (Global Positioning System)-enabled mobile phone logs, are presented. The method of estimation is explained, and the flow of people into and out of the 20 km evacuation zone during the accident is visualized.  相似文献   
3.
Fatigue even increases the complexity of the pedestrian dynamics which is regarded as a kind of nonlinear system, and might have a significant negative impact on the crowd evacuation. However, it has never been investigated completely and properly. Thus, the fine discrete floor field cellular automata model is modified by integrating the fatigue function to explore the influence of fatigue on the crowd ascending evacuation. The simulation fits well with the empirical data and the observations quantitatively and qualitatively, indicating the model captures the main features of evacuation considering fatigue impact. As a prediction, without merging streams, compared with the case of walking in constant speed, when fatigue is considered, it takes 71.4% longer for all persons to enter the stairs and 87.2% longer to evacuate. With merging streams, fatigue has little impact on the inflow, while it makes the total evacuation time 84.2% longer.  相似文献   
4.
CR-39 Solid State Nuclear Track Detecting foils (SSNTD), along with 1 mm thick polyethylene radiator, sealed in triple laminated pouches, are used for country wide Fast Neutron Personnel Monitoring in India. With the present system of processing by elevated temperature electrochemical etching (ETECE) and evaluation using automatic image analysis, only 16 foils are processed at a time and it is useful over the dose equivalent range 0.2 mSv to 10 mSv. It has been reported that, by processing CR-39 of good detection efficiency by chemical etching at elevated temperature, more numbers of foils can be processed simultaneously. In the present study, CR-39 foils from Pershore Moulding (UK) have been chemically etched using 7 N KOH under various conditions of temperature and etching durations and evaluated using high magnification microscope. The duration of chemical etching, has been optimized at a constant temperature of 60°C for chemical etching process. The characteristics of the chemically etched CR-39 foils are compared with the characteristics of the CR-39 foils processed by the existing system of ETECE and the detailed results are presented in the full text of the paper. It has been observed that by chemical etching process, the dose equivalent range of CR-39 foils can be extended above 60 mSv.   相似文献   
5.
认可机制下实验室人员培训工作的组织与开展   总被引:1,自引:0,他引:1  
针对部分实验室在人员培训工作中存在的培训模式不清、培训机制不健全、培训质量较低的问题,系统地分析了计量实验室人员培训所涉及的主要类别、内容及要求等。对培训工作的流程逐个进行详尽地描述,分内部培训和外部培训两个方面对培训中应注意的问题进行重点说明,为广大计量实验室管理人员开展人员培训工作提供借鉴。  相似文献   
6.
彭年斌  牟谷芳 《大学数学》2011,27(4):133-136
《数学实验》是在大学数学教学中将理论教学与实验教学融为一体的一门实验科学课程.阐述了在独立学院开设数学实验课的必要性和深远意义,以及在独立学院建设数学实验课的构想.  相似文献   
7.
基于生态学视角构建了科技人才效能评价指标体系,通过运用生态位模型和Malmquist指数分析了我国30个省市的科技人才效能的发展程度和产出效率,结果表明,第一,我国东部和中西部地区之间的科技人才效能呈现较为明显的区域性差异;第二,技术进步效率对我国30个省市科技人才效能全要素生产率具有较明显的影响,应该引起重视;第三,从分区域全要素生产率指数的变动情况来看,全要素生产率最高的为中部地区,其次为东部地区和东北地区,最低为西部地区.  相似文献   
8.
永贵  黄海军  许岩 《物理学报》2013,62(1):10506-010506
利用改进的层次域元胞自动机模型,研究了正菱形网格空间中的行人疏散问题.这类网格可以避免行人贴近房间墙壁或障碍物,转移概率考虑了各种逃生受阻因素.数值仿真显示,出口处的行人分布与实验快照展示的行人分布基本相同,疏散时间和出口宽度呈线性关系,行人流率接近实验结果.  相似文献   
9.
房间出口位置及内部布局对疏散效率的影响研究   总被引:5,自引:0,他引:5       下载免费PDF全文
朱孔金  杨立中 《物理学报》2010,59(11):7701-7707
利用先前建立的元胞自动机人员疏散模型,考虑教室类房间内过道区域的影响因素,调整行人转移概率的计算规则,分析了教室不同出口位置、教室内不同布局情况下的疏散效率.结果表明,正对教室过道的出口对疏散是很有利的,教室正面边缘开口和侧面开口相比,宜在侧面开口,以减少行人运动过程中方向的变化,而教室正面中央开口虽然疏散效率最高,但这样的开口不现实;另外,当教室侧面开口时,紧靠出口墙壁侧的过道是必要的,当教室总容量不变时,应优先考虑过道分布的设计,过道的数目和单个过道宽度相比,过道数目对疏散效率的影响更显著,过道数量较多时,疏散效率较高.本文有望为教室内部布局和出口设置,以及影剧院、体育馆看台等类似建筑内座椅和过道的分布设计提供建议.  相似文献   
10.
With the development of transportation, the tunnel has become one of the important facilities of railway, highway and subway transportation. However, fire hazards occurring inside the tunnel may incur huge numbers of casualties and property losses. In this paper, a breathing air supply zone combined with an upward ventilation assisted tunnel evacuation system (BTES) is introduced. It can be used to create a safe, smoke-free evacuation passageway out of the tunnel. The BTES is optimized to achieve high-performance. The impacts of heat release rates, fire source locations and fire detection times are also discussed.  相似文献   
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