低热释放聚碳酸酯材料的开发进展

阐述了民航飞机客舱用低热释放聚碳酸酯材料开发的意义;介绍了材料热释放的测试方法和现有的民航适航强制性规章和标准;分析了低热释放聚碳酸酯材料的开发价值;详细讨论了各种阻燃聚碳酸酯材料的热释放特性和低热释放聚碳酸酯材料的开发途径。     

原水水源切换对供水管网中铁释放的影响

针对不同水质水源切换引起管道腐蚀导致管网出水水质不达标的问题,对济宁市地下水和南水北调水的水质进行了检测,利用中试管网系统探究了两水源切换及管网水中不同浓度的硫酸根、氯离子对中试管网出水总铁浓度的影响.结果表明,南水北调水水质较差,Langelier饱和指数(LSI)和Larson指数(LR)明显高于济宁市地下水,水源切换后,管网铁释放量明显升高,出水总铁含量和浑浊度无法满足标准限值.在管网铁释放的影响因素中,和碱度相比,硫酸根和氯离子含量是首要影响因素.管网出水总铁释放量与硫酸根离子和氯离子含量呈正相关性,控制硫酸根质量浓度小于150 mg/L,氯离子质量浓度小于100 mg/L,可减缓管网铁腐蚀.     

石蜡/纳米石墨复合相变储热材料的换热与放热效率

相变储热是提高能源利用率的重要手段之一,相变储热材料的换热系数与放热效率研究对太阳能高效利用具有重要意义。通过变换铝管管径、循环风速以及空气温度,计算出复合相变储热材料的换热系数及放热效率。结果表明:铝管管径不变,循环风速小于3m/s时,空气温度对换热系数影响很小,差值在1W/(m2·℃)左右;换热系数、放热效率都随风速的增大而有所提高,放热效率最大可达95.3%;随着管径增大,换热系数逐渐减少,放热效率却逐渐增大;适合石蜡/纳米石墨复合相变储热材料的最佳条件为管径30mm、循环风速3m/s以及空气温度90℃。     

绝热式炸药爆热热量计绝热性能的测定方法

通过测试绝热式热量计量热体系的冷却常数,确定量热体系与周围环境进行的热交换量,以此来衡量绝热量热仪的绝热性能.介绍了绝热式量热体系冷却常数及量热体系与周围环境热交换量的测试方法.通过测量绝热量热体系与周围环境的热交换量可以比较绝热量热仪绝热性能的好坏,找出影响热交换量的试验因素.通过调节试验条件及试验配置,选择最合理的试验环境,减小量热体系与周围环境的热交换可以提高测量炸药爆热的试验准确度.还可根据热交换量的大小来判断量热体系设备配置的合理性.     

加速量热仪压力数据的应用

由加速量热仪实验测得硝酸铵及其乳胶基质的压力数据,分析认为采用压力数据进行物质危险性分析是可行的.根据压力测试数据进行动力学计算,运用机理函数g(α)=(1-α),计算了含有硝酸铁的硝酸铵的活化能E为197.35kJ/mol,根据温度计算的活化能为195.41kJ/mol,表明用压力数据分析材料的热危险性和计算反应活化能是可行的.     

Ignition Temperature of Coal. 4. Influence of the Heating Rate and Degree of Oxidation

Apparatus for determining the oxidation of coal according to Ukrainian State Standard DSTU 7611:2014 is used to determine the influence of the heating rate and degree of oxidation of coal on its ignition temperature. By means of the Kissinger equation, the activation energy, preexponential factor, and rate constant of ignition are calculated for coal samples of different metamorphic development and degree of oxidation. The rate constant of ignition increases with increase in the degree of oxidation and decrease in the metamorphic development of the coal. Oxidation increases not only the rate constant but also the activation energy of coal ignition.     

影响窑具使用寿命的因素及提高窑具抗热震性途径

概述了我国窑具行业的现状,运用理论和实践分析了影响窑具使用寿命的因素,并提出了提高窑具抗热震性的途径。     

实木家具VOC释放组分水平分析

实木家具是室内空气污染的重要来源。到目前为止,我国实木家具有害物质检测还一直停留在单一甲醛项目的检测控制上,因此迫切的需要对实木家具中除甲醛外的污染物散发种类及含量进行研究评价,进而推动我国家具产品VOC限量标准尽早出台。     

岩石乳化炸药绝热分解安全性的加速量热法分析

用加速量热仪研究了岩石乳化炸药的绝热分解过程，得到了绝热分解温度与压力随时间的变化、自加热速率与分解压力随温度的变化曲线以及压力转化分数随时间的变化曲线，并分析了热分解过程，计算了分解动力学参数表观活化能和指前因子，据此分析了岩石乳化炸药的安全性，表明乳化炸药具有良好的热稳定性。     

聚甲基丙烯酸甲酯材料强制点燃研究

使用锥形量热仪研究了聚合物材料PMMA(Poly(methyl methacrylate))在不同热通量下的强制点燃,得到其相应的点燃时间和临界表面温度。同时考虑到强制点燃过程中气、固相的能量和质量传递及化学动力学过程,给出了一种描述聚合物材料强制点燃的气相和固相数学模型,并对实验结果进行了计算,同时与文献数据进行了比较,其计算结果与实验值吻合较好。     

基于绝热加速量热测试的过氧化叔丁基反应失控的泄放设计(英文)

In order to design the relief system size of di-tert-butyl peroxide(DTBP) storage tanks,the runaway re-action of DTBP was simulated by accelerating rate calorimeter(ARC).The results indicated that under adiabatic conditions the initial exothermic temperature was 102.6 ℃,the maximum self-heating rate was 3.095×107 ℃·min-1,the maximum self-heating temperature was 375.9 ℃,and the pressure produced by unit mass was 4.512 MPa·g-1.Judged by ARC test,the emergency relief system for DTBP was a hybrid system.Based on Design Institute for Emergency Relief System(DIERS) method,the releasing mass flow rate W was determined by Leung methods,and the mass velocity G was calculated by two modified Omega methods.The two relief sizes calculated by monograph Omega method and arithmetic Omega method are close,with only 0.63% relative error.The monograph Omega method is more convenient to apply.     

火药爆热热量计检定用标准物质的研制

采用硝化棉、硝化甘油、中定剂和凡士林为火药爆热热量计检定用标准物质的组成成分,通过生产工艺优化制备出该标准物质。对标准物质特性量值（爆热值）的均匀性采用方差分析方法进行检验,并进行1a以上的稳定性考核,并且通过定值、定值结果的不确定度分析以及在不同单位火药爆热热量计上的试用表明,该标准物质特性量值准确、可靠,均匀性和稳定性好,可以达到火药爆热量值传递以及校准和检定火药爆热测试仪器的要求。     

蓄热室格子砖老化对热交换效率的影响

窑炉的能耗随着生产时间的延长呈增加趋势,这一点以前并没有引起足够的重视。对于5年以上窑龄的窑炉,这种现象开始逐渐受到关到,本文从蓄热室的换热机理和格子砖的剖析阐述了蓄热室格子砖的老化是影响窑炉能耗随时间呈增加趋势的重要原因,并提出改进措施和建议。     

Fe2O3对MCA阻燃尼龙6体系热释放速率的影响

研究了Fe2O3对尼龙(PA)6/三聚氰胺氰尿酸盐(MCA)/玻纤(GF)体系阻燃性能的影响.热失重、锥形量热仪及燃烧后表面形貌分析表明,Fe2O3对PA6/MCA/GF体系有促进分解的作用,热释放时间提前,热释放速率峰值明显降低且变化平稳,Fe2O3对该体系燃烧中形成的炭化层有加固作用,有效阻隔可燃气体的释放及热量的传递.     

采用加速量热法评价防爆硝酸铵的热稳定性

在模拟硝酸铵(AN)的生产工艺流程中加入防爆添加剂制成防爆AN,按照工业炸药配方制成铵油炸药,并用8^#雷管起爆,实验表明该防爆AN失去了爆炸性。用加速量热仪研究了AN和防爆AN的绝热分解过程,得到了绝热分解温度与压力随时间的变化、自加热速率与分解压力随温度的变化曲线,计算了分解动力学参数表观活化能和指前因子。据此分析了防爆AN的安全性,表明它具有良好的热稳定性;同时也表明防爆AN热稳定性的提高是爆炸特性得以消除的原因。。     

Influence of the Metal Particle Size on the Ignition of Energetic Materials

A theoretical study of multi‐particle ignition uses a hot spot model which calculates the temperature evolution of individual hot spots in an energetic material. It indicated that ultra‐fine hot particles would be very effective in igniting energetic materials if impinging and penetrating the solid propellant. Igniting mixtures were prepared containing ultra‐fine Ti particles which react fastest compared with coarse particle mixtures, standard B/KNO₃ and black powder. The ultra‐fine particles, however, are obviously oxidized or gasified too fast as to reach the energetic material to be initiated and longer ignition delays are found mainly compared with coarse particle mixtures. An optimized mixture of coarse and ultra‐fine particles would give an improvement of ignition delay times.     

Mathematical expression of Heat Release Rate Curve and proposal of ‘Burning Index’

Heat Release Rates of organic materials are studied in many countries, but there is no mathematical formula to represent their shape. We considered a mathematical expression of the Heat Release Rate Curve by a simple equation. And we also derived the index of degree of combustibility, named ‘Burning Index (BI)’. The Heat Release Rate Curve is expressed by the derivative of a probability function of maximum value and has three parameters; an amplitude coefficient, a time width coefficient and an ignition index. BI is in proportion to an amplitude and a time width and in inverse proportion to an ignition index. BI values of cable plastic compounds with flame-retardant material had good relations with the quantity of non-organic ingredients. © 1998 John Wiley & Sons, Ltd.     

The Accumulation of Flammable Gases in Cone Calorimeter Tests is Responsible for Flash Ignition of Wool and Cotton Samples

In this paper a possible explanation is presented for the differences found between the fire behaviour of materials in small-scale cone calorimeter tests and the large-scale furniture calorimeter. The results obtained with cone calorimeter/FTIR equipment at 35 kW m⁻² will show that the early flash ignitions of typical materials like cotton and wool are due to the liberation of flammable gases during the pyrolysis phase and the typical ignition situation on the cone calorimeter, that is, the presence of a sparking igniter above the sample. This fast flash ignition and the early heat release behaviour on the cone calorimeter may be in contradiction to the early fire growth in other fire tests where the ignition conditions are clearly different from pyrolysis circumstances, that is, ignition via a burning newspaper, match, gas flame, etc.     

微囊化樟脑油相对释放速率的研究

在常温、常压下用失重法研究了樟脑油微囊的相对释放速率,并考察了释放速率与样品合成时水相pH、水相离子强度、微囊化、温度及空气相对湿度的关系。