磷-硼协效阻燃的云南松燃烧性能和热解动力学

为探讨磷-硼协效阻燃体系对云南松燃烧性能和热解动力学的影响,利用极限氧指数(LOI)测定仪、木垛法、锥形量热仪和热重(TG)分析等手段,开展有关磷酸二氢铵和硼砂协效阻燃的云南松的燃烧性能和热解特性的试验研究,并运用Kissinger和Flynn-Wall-Ozawa模型分析其热解动力学。结果表明:磷酸二氢铵和硼砂复配使用对云南松有较好的协效阻燃作用;当磷酸二氢铵和硼砂质量比为4∶1时,所阻燃的云南松的热释放速率(HRR)和总释放热(THR)相比于纯云南松分别下降了62.8%和56.5%,LOI高达66.5%;磷酸二氢铵和硼砂协效体系通过提高云南松热解的表观活化能有效增强了云南松的高温稳定性、成炭能力和阻燃性能。     

含碳纳米管的有机-无机杂化膨胀阻燃剂的合成及其应用

通过在磷酸季戊四醇三聚氰胺盐(PPMS)合成过程中加入碳纳米管(CNT)合成一种新型的有机-无机杂化膨胀阻燃剂(PPMSCNT),并结合傅里叶红外光谱(FTIR)和热重分析(TG)对其结构和性能进行分析。将所合成的PPMS和PPMS-CNT分别加入环氧树脂中,利用FTIR、TG、锥形量热仪和烟密度试验对其阻燃和抑烟性能进行测试。结果表明,相同添加量下的PPMS-CNT在环氧树脂中阻燃和抑烟效果明显优于PPMS。添加质量分数15%PPMS-CNT时,阻燃环氧树脂的峰值热释放速率、总释放热、峰值生烟速率和总生烟量相比于纯EP分别下降了68.2%、28.8%、66.7%和42.8%。热重分析表明,PPMS-CNT相比于PPMS能更有效地增强环氧树脂的热稳定性和成炭性能,进而表现出较好的阻燃和抑烟效果。炭层分析表明,CNT的加入能促进PPMS在膨胀过程中形成更多的P—O—C交联结构,以有效增强炭层的致密性。研究表明,含碳纳米管的有机-无机杂化膨胀阻燃剂的加入能显著提高环氧树脂的阻燃和抑烟性能。     

一种采用MPP对棉织物进行阻燃处理的方法

对可燃织物进行改性使其具备一定的阻燃性能已成为现今研究的热点。本实验由光敏剂二苯甲酮(BP)引发聚磷酸蜜铵(MPP)在棉织物表面发生接枝聚合,然后对棉织物进行阻燃整理,考察了单体浓度、光敏剂浓度对棉织物增重的影响,运用SEM观测了改性前后棉织物的表面形貌,采用TG研究改性前后棉织物的重量与温度的关系。结果表明,棉织物的增重随着单体浓度、光敏剂浓度的增加出现先增加后减少的趋势;SEM分析表明经MPP改性的棉织物表面形态更具阻燃性能;通过TG测定,发现改性后棉织物的阻燃性能有了很大提高。     

硼酸锌对膨胀阻燃聚甲醛的协效阻燃研究

为进一步提高膨胀型阻燃剂(IFR)对聚甲醛(POM)的阻燃效果,首先将硼酸锌(ZB)与常用IFR(聚磷酸铵-三聚氰胺-季戊四醇)共混制得ZB-IFR复配膨胀阻燃体系的样品,采用熔融共混法制备ZB-IFR/POM复合阻燃材料;然后利用极限氧指数(LOI)测定仪、垂直燃烧(UL-94)测试法、热重分析(TGA)法、扫描电镜(SEM)、锥形量热仪(CONE)及热重-红外(TG-IR)仪等研究ZBIFR对POM的协效阻燃作用。结果表明:当ZB含量为1%时,所得1.0ZB-IFR/POM的LOI可达55%,UL-94等级为V-0级;其受热膨胀后所得残炭量高,炭层结构致密稳定,且在燃烧过程中的热释放速率(HRR)、质量损失及烟气释放量均最小,火灾性能指数(FPI)相对最高;除此,不含ZB的IFR/POM在受热分解过程中比1.0ZB-IFR/POM放出更多的CO2,说明ZB的加入能有效地抑制复合阻燃材料的充分燃烧,显示出良好的协效阻燃作用。     

溴-锑-磷协效阻燃体系对聚丙烯土工格栅阻燃和生烟性能的影响

利用极限氧指数、垂直燃烧试验、酒精喷灯燃烧试验、锥形量热仪、热重分析和力学性能测试等手段研究了溴-锑-磷阻燃体系对聚丙烯(PP)土工格栅的力学性能、燃烧性能、生烟性能和热解特性的影响。结果表明,低添加量(质量分数≤5%)的溴-锑-磷阻燃体系对PP土工格栅的拉伸强度和断裂伸长率影响较小,但明显提高了材料的阻燃性能,其中质量分数5%的四溴双酚A-双(2,3-二溴丙基醚)(八溴醚)-三氧化二锑阻燃PP的峰值热释放速率(HRR)和总释放热(THR)相比于纯PP分别下降了39.98%和26.03%。八溴醚-三氧化二锑阻燃体系与红磷复配时还表现出较好的协效作用,当溴-锑与磷的质量比为3∶2时,协效阻燃效果最优,仅添加5%的协效阻燃体系便可使PP的LOI和UL 94等级分别达到27.9%和V-0级,并通过酒精喷灯燃烧试验。与纯PP相比,溴-锑阻燃体系虽降低了PP的HRR和THR,但增大了燃烧过程中的生烟速率(SPR)和总产烟量(TSR),而红磷的加入能有效降低溴-锑阻燃PP的生烟量。热重分析表明,溴-锑-磷协效阻燃体系表现出较好的气相阻燃作用,能有效降低PP的热裂解速率,增强了PP的阻燃性能。     

三氧化钼与有机蒙脱土复配体系在膨胀阻燃环氧树脂中的应用

为了提高膨胀阻燃环氧体系的阻燃和抑烟效率,利用聚磷酸铵-季戊四醇-三聚氰胺为膨胀阻燃剂、有机蒙脱土(OMMT)和MoO3为复配协效剂制备了膨胀阻燃环氧树脂,通过极限氧指数(LOI)、UL94、锥形量热仪和烟密度试验研究了膨胀阻燃环氧树脂的阻燃和抑烟性能。结果表明,单独添加OMMT或MoO3均能有效提高膨胀阻燃环氧树脂的LOI并降低燃烧过程中的热释放和生烟量,将二者复配使用还表现出较好的协效作用。添加质量分数1.5%OMMT和1.5%MoO3时,膨胀阻燃氧树脂的LOI达到27.8%,UL94达到V-0级,总释放热(THR)和总产烟量(TSR)相比未添加协效剂的膨胀阻燃环氧树脂分别下降了49.5%和57.8%。热重分析表明,单独添加OMMT或MoO3均能有效提高膨胀阻燃EP的热稳定性和成炭率,二者复配使用则表现出更高的初始分解温度并形成更多的残炭量。扫描电镜和红外光谱分析发现,OMMT和MoO3复配使用能促进膨胀阻燃氧树脂在燃烧过程中形成更多的交联结构以增强炭层的致密性和隔热性能,达到协效阻燃和抑烟作用。     

含二羟基DOPO衍生物阻燃改性环氧树脂的制备与热性能研究

DOPO(9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物)、多聚甲醛、二乙醇胺为原料合成了含二羟基的DOPO衍生物DHDOPO,并作为反应型阻燃剂引入到环氧树脂分子链结构中,制备出一组不同含磷量的阻燃环氧树脂复合材料。采用极限氧指数(LOI)法和垂直燃烧(UL-94)法测试材料的燃烧性能,结果表明,在含磷量为1.5%时,氧指数达到35.0%,并达到V-0级别。锥形量热计(Cone)数据显示阻燃改性后的环氧树脂具有更低的热释放速率峰值(PHRR)和总热释放量(THR),说明具有更高的火灾安全性。此外,还通过热重分析(TGA)实验研究了DHDOPO对环氧树脂热稳定性能的影响。通过扫描电镜对燃烧过后的炭渣形貌进行分析,推测了燃烧的过程和阻燃的机理。     

HIPS阻燃复合材料三元潜在火灾危险性评价

将高抗冲聚苯乙烯树脂颗粒(纳米/微米级)、十溴二苯乙烷颗粒、三氧化二锑、弹性体、分散剂和偶联剂通过一步熔融共混工艺先行制备UL94 V-0级阻燃母粒,再将其与HIPS本体树脂按不同比例混合制得阻燃复合材料,并利用极限氧指数(LOI)、垂直燃烧(UL94)及ISO 5660锥形量热计三项测试表征制得样品的燃烧和火灾性能,从中提炼和分析LOI、垂直燃烧等级和最大热释放速率(Pk HRR)等三元关键指标相关性,给出了定性定量相结合的潜在火灾危险性分级范围。结果表明:UL94燃烧等级和Pk HRR相关性体现为当Pk HRR≤330.0 k W/m~2时,试样UL94等级均为V-0级;UL94燃烧等级和LOI相关性体现为随UL94燃烧等级从V-0降到HB时,试样LOI从27.0降到17.0;Pk HRR与LOI相关性体现为Pk HRR与LOI呈粗略反向线性相关性;UL94燃烧等级、Pk HRR和LOI三元相关性体现为当LOI22.0、Pk HRR为399.0~665.0 k W/m~2时,材料UL94燃烧等级介于HB~V-2。     

三嗪和磷腈阻燃剂作碳源阻燃聚乳酸复合材料的性能研究

为了探究三嗪和磷腈类碳源对聚乳酸阻燃性能及力学性能的影响,提高阻燃效率,利用苯氧基聚磷腈(SPB100)、三嗪类膨胀阻燃剂(FP2200)作碳源分别与聚磷酸铵(APP)按不同配比复配,采用熔融共混法制备了阻燃聚乳酸复合材料,总添加量保持10％.通过热重分析(TGA)、极限氧指数(LOI)、垂直燃烧(UL-94)和锥形量热法分析了2种膨胀阻燃体系对阻燃聚乳酸热稳定性和阻燃性能的影响,采用拉伸试验评价了阻燃聚乳酸的机械性能,并采用扫描电子显微镜和傅立叶变换红外光谱研究了阻燃聚乳酸残炭的化学结构和组成,并分析了阻燃机理.结果表明,当SPB100/APP的质量比为7/3时,LOI达到28.5％且达到UL-94 V-0等级,拉伸强度为49.7 MPa.研究表明,两种碳源均可改善阻燃聚乳酸的热稳定性、抗滴落性能和阻燃性,能满足阻燃要求,其中添加SPB100的阻燃聚乳酸复合材料的力学性能更优.     

β环糊精改性聚氨酯基涂料的火安全性与热解动力学分析

为提高膨胀型防火涂料的阻燃性能,以聚氨酯树脂为基料,以聚磷酸铵、尿素为阻燃体系,通过加入不同掺量的钛酸酯偶联剂改性β-环糊精(β-CD),提高阻燃效果。通过红外光谱仪(FT-IR)、锥形量热仪(CONE)、热重分析仪(TG)、差热扫描量热仪(DSC)等,研究改性β-CD的含量对膨胀型防火涂料的火安全性的影响,使用Coats-Redfern积分法计算涂料的热解动力学。研究结果表明：改性β-CD能有效地提高涂料的阻燃性能,当β-CD为1wt%时拥有最佳阻燃性能,1wt%改性β-CD能够提高涂层的蓄热能力,延缓APP的分解和抑制碳质材料的分解,进而提高涂料的阻燃性能。通过热解动力学拟合曲线得出,1wt%的样品能在253℃以后显著提高反应的活化能,提高涂层的阻燃性。     

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。     

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.     

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。     

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。     

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.     

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。