首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
    
The egress strategy in high‐rise buildings has traditionally been based on the sole use of stairs for evacuation. However, it is becoming more common to include evacuation elevators in the egress strategy in high‐rise buildings. Traditionally, evacuation elevators have not been allowed as an evacuation route, and people have been instructed to not use elevators in case of fire. This means that people might still not consider evacuation elevators even if they are designed to be safe in case of fire. Even if people choose evacuation elevators, they might not be willing to wait very long for an elevator to arrive. Virtual reality (VR) experiments were conducted to study exit choice and the waiting time for evacuation elevators in high‐rise buildings. The experiment was performed in a VR lab with a VR model of an existing high‐rise building. Results suggest that a simple way‐finding system using green flashing lights can influence people to more likely choose the elevator as their first evacuation choice. The results also show that the general trend is that people wait for either a limited time (<5 min) or a long time (>20 min). Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

2.
全面介绍了沉井方案的选择、沉井的制作、施工及沉井下沉过程中的纠偏处理,为闹市区高层建筑物地下室的施工提供了成功经验。  相似文献   

3.
介绍了用小波变换方法测试高层建筑的基本思想及具体分析方法 ,为高层建筑物动力检测的研究提供了一个基本的框架。应用小波变换多分辨率的特点 ,并与傅立叶变换相结合分析结构阻尼比 ,以上海地区几幢高层建筑为特例给出了动力特性的测试和分析方法 ,以及测试结果。结果表明 ,应用小波变换确定的阻尼比精度与其他方法相比有所提高。  相似文献   

4.
    
To predict the time that a building will take to be evacuated in an emergency and to design lift systems capable of dealing with the demand, building designers need an understanding of the likely exiting behaviour of occupants. Because of the inherent difficulties of carrying out research in human behaviour, a number of approaches have been used in this investigation, including analysis of data from past fire events and a number of surveys. The results from this work suggest that the split of occupants using the stairs or lifts to evacuate is governed predominantly by floor level of the occupant and that it is unreasonable to expect that occupants will wait indefinitely for a lift to arrive in an emergency situation. The drop‐off in the percentage of occupants that will continue to wait for a lift with increasing waiting time is dependent on floor height. These results will allow building designers to make more realistic assumptions when designing evacuation strategies incorporating lifts. It is also hoped that a better understanding of the reservations that building users may have about using lifts for evacuation in emergency situations will allow better occupant training programmes to be developed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

5.
分析了在作用面积内自动喷水系统的5种喷头的不同布置间距条件下系统的设计流量,设计流量为强度面积法计算的1.66~3.0倍,其比例参数可用于设计。此外,分析了高区为标准层、低区为带裙楼的公共设施层的商务写字楼和宾馆高层建筑自动喷水灭火系统的设计流量特点和常规选择消防主泵存在的问题,提出以低区工况选泵,按高区工况校核的选泵方法,并给出该法适用范围,同时介绍了水力报警阀、喷头作用水头和泄水装置设置的有关问题。  相似文献   

6.
着重讨论了气压消防设备在高层建筑消防稳压中的应用,探讨了气压罐总容积计算中调节容积Vx的取值及稳压泵的计算  相似文献   

7.
李刚 《水泥工程》2020,33(6):4-7
为进一步了解窑尾塔架在罕遇地震下的工作性能,现以我公司设计的宁夏建材集团产业扶贫产能置换建设5000 t/d项目窑尾塔架进行在罕遇地震下的静力弹塑性分析,简述操作流程,对其工作性能进行分析和总结,为今后类似的结构设计提供参考.  相似文献   

8.
以减缩活性单体2-(2-丁氧乙氧基)乙醇丙烯酸酯(MBDEGAA)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)与聚乙二醇单甲醚丙烯酸酯(MPEGAA)为聚合单体,在水溶液中通过聚合反应,合成了一种高分子聚合物(HP-SRA)。采用红外光谱、核磁共振氢谱和凝胶渗透色谱对HP-SRA分子结构和相对分子质量及其分布进行了表征。并测定了掺入质量分数为0.30%(固含量)的HP-SRA混凝土的减缩性能及应用性能。结果表明,当n(MPEGAA)∶n(MBDEGAA)∶n(AA)∶n(AMPS)=1∶2.15∶2.15∶1.10时,水泥砂浆减缩率最高,水泥净浆流动度及其保持能力最佳。在不影响混凝土应用性能基础上,减缩基团的引入有利于提高混凝土的减缩性能。  相似文献   

9.
    
A high‐throughput screening of candidate nitrilases against 25 structurally diverse substrates allowed us to create a wide collection of 125 experimentally validated nitrilases. The enzymes were selected by genomic approach from 700 diverse prokaryotic species and one metagenome as representative of the nitrilase family diversity. The enzymatic screening of this collection expands the biocatalytic toolbox for chemical synthesis by providing a large number of tested nitrilases with their assigned substrates. Three examples illustrate the synthetic potential of our enzyme collection. The syntheses of carboxylic acid building blocks, a β‐substituted phenylpropanoic acid, a cyclic γ‐keto carboxylic acid and a mononitrile monocarboxylic acid, were achieved from the corresponding nitrile substrates, using three new nitrilases (two from Sphingomonas wittichii and one from Syntrophobacter fumaroxidans). Improvements of nitrilase activities through the optimization of reaction parameters and the preparative biocatalytic synthesis are presented for these three examples.  相似文献   

10.
<正>0前言目前,液力耦合器在工业生产企业广泛使用,它是以液体为工作介质的一种非刚性联轴器,利用液体动能的变化来传递动力。液力耦合器是由带叶片的驱动轮(泵轮装在输入轴上)和被驱动轮(涡轮装在输出轴上)组成一个可使液体循环流动的密闭工  相似文献   

11.
水泥熟料生产线窑尾钢结构框架是水泥厂建设项目中标志性建筑物,施工周期长、作业高度高、交叉作业多、施工危险性大,容易发生安全事故。本文以某6000t/d新型干法生产线窑尾钢结构框架为例,探讨了窑尾钢结构框架安装防护的安全措施。通过实际施工过程中的检验,安全生产绩效显著。  相似文献   

12.
罗明明 《橡胶工业》2021,68(11):0843-0846
以天然橡胶(NR)/溴化丁基橡胶(BIIR)并用胶为主体材料制备建筑隔震支座用高阻尼胶料,考察NR/BIIR并用比、炭黑品种和用量以及增粘剂种类对胶料性能的影响。结果表明:减小NR/BIIR并用比,即增大BIIR用量可以有效增大胶料的等效阻尼比,但会降低胶料的强度和形变能力;选用高比表面积的炭黑N220及增大其用量,能够有效增大胶料的等效阻尼比,但炭黑用量增大到一定程度后胶料的强度和形变能力会迅速下降;树脂类增粘剂种类对胶料性能的影响不大,但苯酚乙炔树脂会减小胶料的等效阻尼比。  相似文献   

13.
在装配车间,不适宜使用大型摇臂钻,但小型摇臂的行程不能满足要求,因此设计了这个旋转工作台。它具有旋转灵活、简单可靠、安全系数高和制造成本低的优点。虽然是针对FA009A的塔座底盘而设计,但是可以适用于类似的一般件,也就是说,在很大程度上,它具有通用性。  相似文献   

14.
15.
刘伟 《化肥工业》2012,39(5):64-65,70
采用高水气比耐硫变换工艺对含CO体积分数高达67.8%(干基)的粗煤气进行深度变换。通过对催化剂装填量的控制和变换炉上、下段气量的分配来控制炉温,使变换气中CO体积分数<0.4%(干基),满足了日产700 t合成氨装置的工艺要求。  相似文献   

16.
在尾管固井、处理井下事故,如堵漏、打底塞、填井等工艺过程中,水泥浆在钻杆中凝固而导致钻杆堵塞时有发生。传统的处理方法是将这些堵塞的钻杆报废,结果造成很大的浪费。在系统研究高压水射流流动规律和动力特性基础上,针对不同喷嘴角度和喷射压力进行研究,找出最合适的角度和压力,根据不同使用条件和适用对象,对水射流参数进行了调整,对钻头切削齿和喷嘴布置进行合理的设计。研究了一项高压水射流处理水泥堵塞钻杆新技术,设计制造了清洗堵塞钻杆的专用设备和工具,现场实验取得了显著效果。  相似文献   

17.
    
An experimental investigation was carried out to evaluate the quality of virgin olive oils obtained when either a hammer‐crusher or a disk‐crusher were used for the olive paste preparation; the effect of the temperature rise caused by rapid olive crushing was also assessed. Oxidative degradation in the oils obtained from hammer‐crushed olives was significantly higher than in those obtained from disk‐crushed olives as shown by the levels of oxidised triacylglycerols and the results of the oven test. A significant inverse correlation (p <0.001) was found between the Rancimat induction time values and the amounts of oxidised triacylglycerols as determined by the high‐performance size exclusion chromatography analysis of polar compounds. These findings suggested that polar compound analyses, just as routine analyses, may be used as a suitable analytical tool to effectively evaluate the quality of virgin olive oils.  相似文献   

18.
19.
Although they represent attractive therapeutic targets, caspases have so far proven recalcitrant to the development of drugs targeting the active site. Allosteric modulation of caspase activity is an alternate strategy that potentially avoids the need for anionic and electrophilic functionality present in most active‐site inhibitors. Caspase‐6 has been implicated in neurodegenerative disease, including Huntington’s and Alzheimer’s diseases. Herein we describe a fragment‐based lead discovery effort focused on caspase‐6 in its active and zymogen forms. Fragments were identified for procaspase‐6 using surface plasmon resonance methods and subsequently shown by X‐ray crystallography to bind a putative allosteric site at the dimer interface. A fragment‐merging strategy was employed to produce nanomolar‐affinity ligands that contact residues in the L2 loop at the dimer interface, significantly stabilizing procaspase‐6. Because rearrangement of the L2 loop is required for caspase‐6 activation, our results suggest a strategy for the allosteric control of caspase activation with drug‐like small molecules.  相似文献   

20.
建筑设计防火规范在石化工业建筑设计中的应用   总被引:1,自引:0,他引:1  
房栋  汪洋  张东辉  郭睿 《当代化工》2007,36(3):308-312
通过对《建筑设计防火规范》GB50016-2006的学习,从六个方面结合实际情况,详细地阐述了《建筑设计防火规范》GB50016-2006在石化工业建筑设计中的实际应用.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号