Thermal decomposition kinetic of liquid organic peroxides

This study demonstrates the application of isothermal calorimeter for investigating the thermal decomposition of several liquid organic peroxides, such as t-Butyl peroxy acetate (TBPA), Di-tert butyl peroxide (DTBP), and Cumene hydroperoxide (CHP). The decomposition mechanism and kinetic can be identified from case to case. TBPA and DTBP undergo first order reaction, whereas CHP occurs autocatalysis. Accurate kinetic can be assessed on the basis of discerning these various schemes of given samples. Consequently, the thermal runaway or reactive hazards potential of organic peroxides can be determined, for instance as a self accelerating decomposition temperature (SADT).     

新一代评估方法——锥形量热仪(CONE)法在材料阻燃研究中的应用

利用新一代评估方法———锥形量热仪法对材料阻燃机理、材料危险性等级划分、烟毒释放评价、材料燃烧性及阻燃性评价等方面的应用进行了分析讨论 ,结果表明锥形量热仪法对阻燃剂、阻燃制品的研究开发及阻燃剂在火灾中的行为研究具有重要意义。     

崩滑流雷达遥感应用潜力分析

综述了我国崩滑流（崩塌、滑坡、泥石流）遥感的应用现状；着重分析了成像雷达遥感在崩滑流识别、监测、预警中具有的独特优势，特别是随着新型成像雷达遥感（极化、干涉雷达）的发展，基于干涉雷达发展的差分干涉测量技术能以一量级甚至更小尺度测量地表形变，在崩滑流研究中能提供定量的动态信息，为崩滑流遥感应用研究注入了新的活力，开辟了新的思路；并指出以雷达（ＳＡＲ）遥感信息为主的多源信息复合解译，能为崩滑流灾害的调查提供更为方便、准确、及时、动态的信息．     

SUSPENSOIDS IN NEW YORK CITY'S DRINKING WATER RESERVOIRS: TURBIDITY APPORTIONMENT1

ABSTRACT: The technique of i ndividual p article a nalysis conducted by s canning electron microscopy interfaced with a utomated X ‐ray microanalysis (IPA/SAX) was used to characterize suspended particulate matter in New York City's drinking water reservoirs and their tributaries. The study covered a two year period and involved analyses of more than 300 samples. The particle cross sectional area per unit volume (PAV), or area concentration, was measured to account for the observed turbidity, a representation of light scattering property of the studied medium. A simple linear model with a nearly zero intercept was able to explain more than 85 percent of the variation in the measured turbidity. Moreover, the particle assemblage was categorized into generic particle types with distinctive geochemical or geological origins. Thus, PAV compositions in terms of particle types could be apportioned into turbidity components based on the model. Inorganic tripton, dominated by aluminosilicate (clay) and silicate of nonbiological nature, was found to be the major turbidity causing constituent in most cases. With the exception of one reservoir where organic detritus was significant, the predicted inorganic particle turbidity agreed with the measured turbidity within experimental error.     

Heavy Metals in Moss and Bark From Urban Area of Florence: A New Cleaness Procedure for Removing Superficial Particulate Matter

Hypnum cupressiforme epiphytic moss and tree bark (elm and holm oak) samples have been collected in three sites of the city of Florence in the period 1995-1998. Lead, zinc, copper, and cadmium were determined by differential pulse anodic stripping voltammetry (DPASV) in about 200 samples collected at different heights above ground. A new clean-up procedure by nitrogen jet has been followed and its efficiency has been also verified by electron microscopy (SEM and ESEM techniques). Lead median contents in moss and bark samples fall within the ranges of 0.052-0.86 and 0.20-1.30 μmoles g^-1 (dry weight), resulting values for moss and bark are proportional to the vehicular traffic density. the increasing use of lead-free gasoline has not been followed by a decrease of lead moss concentration.     

Differential treatment within sports teams,leader–member (coach–player) exchange quality,team atmosphere,and team performance

Using the leader–member exchange (LMX) theory as a theoretical framework, the present study focused on the occurrence of differential treatment by leaders on social and task‐related issues within teams. It was investigated whether team members' perceptions of the frequency and degree of social and task‐related differential treatment by the leader were associated with their evaluation of team atmosphere and team performance, in addition to the effects of the quality of their own working relationship with the leader (LMX quality). The context of this study consisted of interdependent sports teams. The participants were 605 players belonging to 69 amateur sports teams playing various team sports such as soccer, hockey, and basketball. Social differential treatment was negatively associated with team atmosphere and unrelated to team performance. In addition, it was found that the two forms of task‐related differential treatment included in this study were unrelated to team atmosphere and were differently associated with team performance. The results are discussed with reference to the existing leadership literature. Copyright © 2010 John Wiley & Sons, Ltd.     

过氧化甲乙酮的热危险性研究

为研究过氧化甲乙酮(MEKPO)在运输与储存中的热危险性,利用差示扫描量热仪(DSC)对质量分数为52%的MEKPO溶液(以2,2,4-三甲基-1,3-戊二醇二异丁酸酯为溶剂)进行测试,得到其起始分解温度T0约为40℃,比放热量ΔH约为1.24 kJ/g。运用加速量热仪(ARC)对3种MEKPO溶液(40%,45%和52%)及MEKPO纯品(化学纯)在绝热条件下进行了热分解测试,并在此基础上,借助Semenov热爆炸模型,计算得到上述样品在50 kg包件下的自加速分解温度(TSADT)分别为65.64,63.72,55.88和51.17℃。研究结果表明,加入稀释稳定剂是降低MEKPO热危险性的有效途径,且MEKPO混合物中其质量分数越大,其危险性越高。     

偶氮二异丁腈热安全性分析与评估

为获得偶氮二异丁腈(AIBN)在各种热应力条件下的危险参数,通过简化的压力容器试验测试AIBN的热分解激烈性等级,采用差示扫描量热仪(DSC)和绝热量热仪(ARC)对AIBN的热分解过程进行研究,用动力学与热稳定性分析软件AKTS计算动力学参数在整个反应进程中的变化情况,并根据ARC测试结果推算自加速分解温度(TSADT)。结果表明:AIBN的热分解激烈性为Ⅱ类,易呈现爆炸特性;其初始分解温度和TSADT很低,分别约为78℃和61℃,且分解放热过程和熔融吸热过程同时发生。因此,在AIBN的生产、使用、贮存和运输等过程中应加强温度监控,并根据实际情况采取降温措施。     

二溴海因危险性试验研究

为评价二溴海因(简称DBDMH)在使用、储运过程中的危险性,采用75℃热稳定性试验对二溴海因在高热条件下的稳定性进行了研究,采用C600微量热法测试了二溴海因的放热起始温度、分解热,并依据《联合国关于危险货物运输的建议书-试验和标准手册》对其爆炸性进行了筛选,通过固体氧化性试验和家兔皮肤刺激性/腐蚀性试验分别对二溴海因的氧化性和皮肤刺激性进行了测试。结果表明:二溴海因在75℃热稳定性试验过程中没有出现着火或爆炸,未出现自加热迹象,不属于太不稳定不能运输的物质;其分解反应只有一步,起始反应温度大约为157℃,分解热为384.8J/g,不属于爆炸品;二溴海因具有氧化性,根据《联合国关于危险货物运输的建议书-规章范本》其包装级别为Ⅱ级;在家兔皮肤刺激性/腐蚀性试验中未见不可逆损伤,对皮肤具有强刺激性。     

涡流热成像动态检测模式的缺陷信号重构方法研究

在涡流热成像检测中,缺陷信号重构可以有效评定结构的安全性和可靠性,及时预防生产中安全事故的发生,目前大多数信号重构方法都不适用于动态模式的涡流热成像检测。为了对动态模式涡流热成像检测的信号进行重构,提出了1种基于区域扫描的方法,选定区域大小及划分准则,在每帧图像相同位置划分区域,对各个区域内的温度数据进行相应的运算处理并提取结果,以此作为每个区域的重构温度,进而重构出包含所有缺陷温度信息的热像图。结果表明:该方法可以对动态模式下的涡流热成像温度信号进行重构,并能在一定程度上消除噪声,有利于后续的图像处理。