化学氧自救器在使用中供氧温度的变化规律

基于化学氧自救器在使用过程中呼吸气体温度较高的问题,运用气固相非催化反应宏观动力学和传热学等理论结合固定床反应器模型,建立了化学氧自救器供氧药罐供氧时的数学模型,选用我国目前运用较为广泛的ZH30D型隔绝式化学氧自救器作为对象进行供氧温度试验研究.通过试验得出劳动强度和环境温度均对ZH30D型化学氧呼吸器供氧装置防护性能影响显著.结果 表明:在相同的环境温度下劳动强度的增加减少了自救器的有效防护时间,也会造成供氧温度上升速率过快,并最终导致在该环境温度下供氧温度达到最大值的时间缩短;在相同的劳动强度下环境温度越高,供氧温度的上升速率越快,同时缩短了供氧温度达到对应劳动强度下最高值的时间;在超氧化钾的质量足够支持反应的情况下,供氧温度与供氧时间、跑步速度和环境温度呈线性正相关;环境温度在30～38℃时,使用ZH30D型隔绝式化学氧自救器,当人体呼出的二氧化碳体积分数达到4.36％时,有效反应区域能够占据整个药剂层,此时供氧温度最大值约为87℃,该温度在试验条件下不受环境温度和劳动强度的影响.本研究期望为ZH型化学氧自救器的改进提供理论参考.     

青藏线环境条件对列车空调新风量的影响

籽研究外界气象条件对在高海氧地区运行的列车空调新风需求量的影响,以青藏铁路沿线实际气参数和环境为基础,依据室内CO2质量浓度平衡原理,计算弥散供氧方式下列车在不同地区的空调新风量调节值.结果表明,与选取固定室外量温度(40℃)相比,选取极端最高温度时的新风量药约率最大值达5.37%.综合考虑高原列车车内正常人体生环所需氧浓度和良好的室内空气品质要求,提出了一种即能控制氧浓度又能保证室内良好的浓度不超标的确定空调新风量的新思路.本研究对青藏铁路列车空调系统的技术改进和运行管理提供了参考.     

消防逃生用氧烛供氧隔绝式呼吸保护装置

消防逃生需要携带使用呼吸自救器。新型氧烛供氧隔绝式呼吸保护装置主要由防护头罩、氧烛和二氧化碳吸附三单元组成。氧烛产生的氧气通过文丘里管推动头罩内的空气循环,采用氢氧化锂吸收循环气中的二氧化碳。设计了产品结构,对产品性能进行了试验,认为是一种适合普及大众救生的呼吸保护装置。它的研制成功,为今后消防、煤矿、有毒有害环境、三防等逃生自救器的设计提供了一种新的思路,有利于呼吸自救器的发展。     

微波诱导技术用于氧烛制氧的理论研究

传统的氧烛是将氯酸盐或高氯酸盐与金属燃料、催化剂混合后压缩所制得。其产氧原理是利用燃料燃烧所释放的热量来促成氯酸盐或高氯酸盐分解,释放出氧气。氧烛不仅因燃料燃烧而消耗所产生的氧气,而且在产氧过程中往往会产生少量的氯气等有害副产品。为解决上述两个缺陷,笔者提出一种新的微波诱导催化技术来代替传统的燃料加热方法。即在氧烛配方中舍弃燃料,而使用外加的微波作为氯酸盐分解的热源。具体方法是先对氯酸钠氧烛的热过程进行数值模拟,通过反应温度的差异解释氯气作为副产品产生的机理;为验证利用微波诱导加热代替燃料加热的可行性,对TE10基模微波场中氯酸钠的热过程进行数值模拟。计算结果表明,氯酸钠在微波场中升温均匀。因此,微波诱导是抑制产氧过程中有害副产品产生的一种有效途径。     

生氧药剂对矿用化学氧自救器生氧温度的影响研究

自救器是矿山井下必须携带的个体防护装置。通过对不同生氧药剂的化学反应热分析、生氧温度的理论计算和实验测试,详细分析了NaO2和KO2药剂生氧温度的高低及变化,得出:在出现相对最高温度之前,NaO2的反应速度及生氧温度明显高于在同时段内KO2的反应速度及生氧温度;但出现相对最高温度之后,NaO2的反应速度及生氧温度迅速衰减,且其衰减速度较KO2的更快。等量KO2药剂较NaO2药剂的反应时间更长一些。建议矿用自救器优选KO2为生氧药剂。     

化学氧自救器供氧温度理论计算模型

针对化学氧自救器供氧温度过高问题,采用了模拟试验与理论分析相结合的方法进行了研究.模拟试验得出了供氧温度分别随KO2药剂量和人体呼吸频率变化的曲线,且供氧温度变化规律明显.基于试验得出的供氧温度变化规律,根据热力学理论,分析了试验装置的产热、散热及热平衡,经过理论推导建立了 KO2药剂在试验装置内反应的供氧温度计算模型;并将等条件下的供氧温度计算值与试验实测值进行了对比分析及Pearson相关性检验.结果表明,理论模型计算值与试验实测值吻合程度高,且呈显著正相关;表明推导得出的理论计算模型有较高的准确性.化学氧自救器使用时的产热、散热过程与模拟试验装置相似,基于化学氧自救器的相关热交换参数,理论分析所得供氧温度计算模型可用于工程实际,指导化学氧自救器的改进.     

高安全AZH——20型化学氧自救器的研究

介绍了高安全ＡＺＨ——２０ 型化学氧自救器科研成果。重点阐述了该自救器的结构设计、选材、氧烛起动装置和提高ＫＯ２ 片状生氧剂性能等方面的技术创新和改进,对应用高新技术提高自救器的防护性能和安全可靠性作了有益的探索     

利用好氧性嗜碱菌处理棉浆黑液的实验研究

利用经驯化的以嗜碱菌群为主的好氧活性污泥对高碱性棉浆黑液直接进行好氧摇床.结果表明,嗜碱菌生长良好,摇床7 h后,黑液的pH值可稳定下降至10以下.继续摇床,pH最低可降至9.0左右,而CODCr去除率可达40%以上.同时,考察了培养温度、黑液浓度及MLSS对棉浆黑液中CODCr去除率的影响,在培养温度为30 ℃,MLSS在4 000 mg/L左右,原黑液CODCr在4 000-5 000 mg/L时处理效果最好,CODCr去除率最高可达50%.     

矿井避难硐室供氧系统研究

在矿山井下事故发生后的矿工自救中,设置避难硐室是十分必要的.供氧系统是避难硐室内避难人员生存的重要保障,避难硐室具有容载人数多、空间相对较大的特点.针对国内避难硐室采用的地面钻孔供氧、压风供氧、压缩气瓶供氧、化学氧供氧等供氧方式进行了研究,分别通过基本供风量、供氧量等参数的理论计算方法,密闭空间模拟试验的方法来对几种供氧方式进行比较,最终确定避难硐室设置多种供氧方式的必要性,为今后避难硐室供氧系统的构建奠定基础.     

溶氧对好氧颗粒污泥同步硝化反硝化脱氮的影响

好氧颗粒污泥外表和内在的不同溶氧(dissolved oxygen,DO)水平分别适合硝化和反硝化微生物的生长,形成具有同步硝化反硝化功能的脱氮体系.DO水平对颗粒污泥内部厌氧好氧区域的构成有影响,改变DO可以研究氧对好氧颗粒污泥同步硝化反硝化过程的影响.结果显示,反应系统在一定DO参与下对有机物的去除效率较高,各种条件下均能达到90%左右;高DO(≥3.0 mg/L)提高硝化速率,但易造成反应过程中NO2-和NO3-的积累;低DO(≤2.0mg/L)下反应积累的硝化产物少;在颗粒污泥同步硝化反硝化反应过程中适当控制供氧,可减少运行过程中N2O的排放.实验条件下,控制DO在1～2 mg/L为佳;在低DO情况下,NO2-通过短程反硝化反应直接还原为气态的N2O和N2;高DO情况下,大部分NO2-以全程反硝化方式还原为气态氮.好氧颗粒污泥具有良好的硝化反硝化能力,而DO对硝化反硝化过程有很大的影响,且低DO更有利于氮的去除和N2O排放量的降低.     

油浸变压器排油注氮装置在500kV变电站的设计与应用

在分析500kV变电站主变压器消防系统的现状,比较3类消防系统优缺点的基础上,详细论述了主变排油注氮装置的结构组成、工作原理、参数计算、控制系统设计以及需要注意的事项等,为下一步排油注氮装置的推广应用打下基础.     

HAZOP结合What-if方法在某延迟焦化装置除焦中的应用

为克服传统危险与可操作性（HAZOP）定性分析方法在复杂操作、间歇作业等过程中使用的局限性,提出在传统HAZOP定性分析方法的基础上结合What-if（故障假设）方法,对人的不安全行为和操作规程不完备所导致的风险后果分析作出补充。详细说明其技术原理、工作流程等使用细节,系统阐述该方法与传统HAZOP定性分析方法的区别,并在某延迟焦化装置的除焦操作的风险分析中应用。经分析,识别出在“给水-泡焦”节点,有“操作规程错误”场景2项,“操作规程不具体”场景1项,不存在“操作人员未按操作规程执行”场景。研究结果表明:本文方法有效且具有较好效果,可以广泛应用于操作规程/作业指导书审查、作业过程隐患排查等方面,帮助企业开展操作层面的风险识别与管理,提升企业的生产安全水平。     

潞安矿区煤层渗透率的各向异性特征实验研究

为了研究原位煤体渗透性的各向异性特征,以山西潞安常村矿3号煤层圆柱试样为对象,利用TCQT-Ⅲ型低渗煤层气相驱替增产试验装置,对煤样进行加载,并以氮气注入压力2.0 MPa的条件下,分析垂直层理和平行层理2个方向的煤体变形和渗透率变化特征。实验结果表明:煤样在加载过程中,平行和垂直层理煤样渗透率均随着有效应力的增大而减小,平行层理方向的渗透率始终大于垂直层理方向,应力加载初期渗透率急剧下降,最后逐渐趋于平缓;径向应变的增加量与渗透率呈正相关性,且平行层理相关性大于垂直层理;沿平行层理方向的裂隙度大于沿垂直层理方向,沿垂直层理方向的应变量大于沿平行层理方向;应变增加量均随有效应力的增加而逐渐减小。研究结果可为煤层井网布置及优化提供参考。     

Nighttime pedestrian fatalities: A comprehensive examination of infrastructure,user, vehicle,and situational factors

Introduction: Pedestrian fatalities in the United States increased 45.5% between 2009 and 2017. More than 85% of those additional pedestrian fatalities occurred at night. Method: We examine Fatality Analysis Reporting System (FARS) data for fatal pedestrian crashes that occurred in the dark between 2002 and 2017. Within-variable and before/after examinations of crashes in terms of infrastructure, user, vehicle, and situational characteristics are performed with one-way analysis of variance (ANOVA) and two-sample t-tests. We model changes in crash characteristic proportions between 2002–2009 and 2010–2017 using linear regressions and test for autocorrelation with Breusch-Godfrey tests. Results: The increase in fatal nighttime pedestrian crashes is most strongly correlated with infrastructure factors: non-intersection unmarked locations (saw 80.8% of additional fatalities); 40–45 mph roads (54.6%); five-lane roads (40.7%); urban (99.7%); and arterials (81.1%). In addition, SUVs were involved in 39.7% of additional fatalities, overrepresenting their share of the fleet. Increased pedestrian alcohol and drug involvement warrant further investigation. The age of pedestrians killed increased more (18.1%) than the national average (3.2%). Conclusions: By identifying factors related to the increase in nighttime pedestrian fatalities, this work constitutes a vital first step in making our streets safer for pedestrians. Practical Applications: More research is needed to understand the efficacy of different solutions, but this paper provides guidance for such future research. Engineering solutions such as road diets or traffic calming may be used to improve identified infrastructure issues by reducing vehicle speeds and road widths. Rethinking vehicle design, especially high front profiles, may improve vehicle issues. However, the problems giving rise to these pedestrian fatalities are likely a result of not only engineering issues but also interrelated social and political factors. Solutions may be correspondingly comprehensive, employing non-linear, systems-based approaches such as Safe Systems.     

Footedness and Mounting—Short Review and Two Case Studies

Footedness is a personal quality like handedness. Footedness may be associated with moving ability during mounting, dismounting, and jumping movements. Occupational accidents have occurred during movement at different working levels, during the use of access and exit systems, and during the mounting of vehicles. Aging can also affect accident risk and body laterality. For example, falling accidents on stairs are common among the elderly. One reason for accidents may be that the structure of the access system or stair system is unsuitable for individual moving patterns depending partly on body laterality. Footedness and the way the feet are used may be contradictory to the demands of the moving situation, especially during uncommon or rapid situations. This contradiction may trigger disturbance during moving. The aims of this pilot study were (a) to review the literature briefly and (b) to describe the use of the dominant and nondominant foot by farmers and the elderly when mounting a tractor and stairs, respectively. The study also gives ideas for future studies based on both (a) and (b).     

AHP与GA-SVM耦合模型在滑坡预警中的应用*

为了减少滑坡造成的损失,提高滑坡预测的准确性,通过搭建灾害模拟平台获得滑坡的实验数据,在获得多组模拟实验数据后,分析各变量的特性。首先,通过层次分析(Analytic Hierarchy Process,AHP)算法,对滑坡进行危险度划分;然后,通过支持向量机(Support Vector Machine,SVM)建立模型,遗传算法(Genetic Algorithm,GA)再优化SVM参数,提出1种层次分析法与GA-SVM相耦合的模型。研究结果表明:AHP方法划分后的数据,通过GA与SVM结合建立的模型精度较好,实验预测结果与实际结果较为吻合,与单一SVM相比,精度更高,结果更好,更加适用于多变量的复杂非线性滑坡预警。     

Debunking the false dichotomy of leadership idealism and pragmatism: Critical evaluation and support of newer genre leadership theories

Leadership theories have shifted over the last few decades from a focus on managerial functions and economic leader–follower exchanges toward greater focus on the interpersonal dynamics occurring within the leadership process. Theories such as transformational, ethical, authentic, and other “newer genre” theories were created to address neglected topics such as leader vision and inspirational messages, transparency, emotional effects, morality, individualized attention, and intellectual stimulation. Critiques of these theories, however, have been raised. In this paper, we address five of those critiques and argue for the validity and practical effectiveness of the new genre theories. Further, we describe how newer genre leadership research should be viewed as a performative epistemology, entailing a process of co‐creation involving scholars and practitioners. Finally, from this view, we provide general ideas for leader development. Copyright © 2014 John Wiley & Sons, Ltd.     

Occupational Safety and Health in Finland

In Finland, occupational safety is the responsibility of the employer, while the occupational safety and health laws are enforced by the Labour Inspection Service, an organization of the state. The Labour Inspection is divided in 11 administrative districts, and it employs 360 professionals. They are mandated to carry out site visits without prearranged appointments to inspect safe work situations, working hours, construction safety, or any aspect of accident risks. The inspectors are also mandated to verify the existence of sufficient occupational health services as prescribed by the Occupational Health Services Act for all employees. The occupational health services are typically provided by enterprise-owned medical departments, by mutually owned health care centers, by private practitioners, or by municipal health care centers. The latter are required by law to provide all services as prescribed by the legislation to anyone who comes to the facility. This situation is prevalent in the countryside, where there are very few private caregiving centers. Declaring occupational accidents and disease cases is mandatory, and the Inspection districts examine all accidents to establish causes and consequences, and to initiate prosecution in case of criminal negligence. Labour Inspection Districts are also notified of the new occupational disease cases as they are declared to insurance companies. Insurance for occupational disease, accidents, and death is an obligation of the employer, although they can choose the insurance company. The medical confidentiality between the workers and their occupational health care providers is very strict. Official statistics are maintained by the state Statistics Finland organization, and they may be used, for example, for research purposes by scientific institutes like the Finnish Institute of Occupational Health. Construction industry accounts for 25% of all fatal accidents (120 cases per 1 million working hours), followed by mechanical, wood, metal, machinery, and pulp and paper industry (10% each of fatal accidents) with rates ranging from 100–160 cases per 1 million working hours. There are some 5,000 occupational disease cases per year (rate 22/10,000 employed). The major disease categories include repetitive strain injuries (1,300 cases), respiratory allergies (600 cases), occupational skin diseases (1,000 cases), and 900 cases of noise-caused hearing loss. In 1998, 589 cases of asbestos-related diseases were reported.     

森林地表火蔓延模拟方法及其计算机实现

进行了森林火蔓延的研究,对传统的经验公式和模型进行改进,明显发现改进的模型有更好的结果,用计算机巧妙准确地实现了模拟模型,在风力不是特别大,地形变化不是特别剧烈时,该模型有较高精度;并结合火蔓延的主要因素（气象因子、气候、地形等）,进行系统分析,写出算地,编制实现地表火蔓延的预测预报计算机系统软件。这对于有效的组织扑救、减少火灾损失、计算森林火灾的损失评估有重要意义。     

公路隧道火灾逃生疏散研究

以苍岭隧道为背景,首先采用经验计算理论和计算软件building EXODUS相结合的方式,从被困人员的安全疏散时间、高温烟气的影响、隧道横通道的利用率以及人员的疏散行为特性进行了研究。结果表明:中小规模火灾情况下的安全疏散时间控制在8 min之内,高温烟气影响不大,但横通道的利用率不平均,且人员疏散路线相对集中。然后对存在的逃生疏散问题提出针对性建议以及其他相关建议,旨在为更大程度降低事故的严重性和经济财产损失。