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81.
液化石油气作为一种清洁、方便能源在天然气逐渐进入城市家庭的今天仍然占据城乡接合部以及农村市场的绝大多数用户,农村地区随着经济生活条件的改善,逐渐淘汰了以"砍柴"、烧土灶的生火做饭方式,液化石油气成为了主要的能源,但由于液化气独特的性质,发生的越来越多的使用过程安全问题也充分暴露出城乡接合部以及农村液化石油气市场存在诸多的消防安全隐患。 相似文献
82.
An Information Diffusion Technique for Fire Risk Analysis 总被引:1,自引:0,他引:1
IntroductionRiskreferstoadverseanduncertainoutcomes.Fireisdangeroustopeopleandproperty,anditoccursuncertainly.Ingeneral,fireriskismeasuredbytheprobabilityoffireoccurringandthemajortaskofriskanalysisistoestimatetheprobabilitydistributionaboutafirewithrespecttodifferentlevels.Theprobabilitydistributionmightofferabaseforriskmanagement,toreduceorcontrolfirerisk.Infireriskanalysis,therearetwooutstandingproblemsthatdeserveourattention.First,asystemwhereafiremayoccurisgenerallytoocomplextobecaptured… 相似文献
83.
Xiaoxia Zheng 《Polymer Degradation and Stability》2006,91(1):108-113
An oligomerically-modified clay containing maleic anhydride was used to prepare polystyrene-clay nanocomposites by melt blending and the effect of this modified clay on the thermal stability and fire performance was studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed immiscible/intercalated/delaminated morphology. The maleic anhydride modified clay improved the compatibility between the clay and the polystyrene. 相似文献
84.
减少和控制火灾的基本手段之一是火灾风险的评价和预警。目前,就单栋或局部区域高层建筑而言,对火灾风险的评价方法已有不少研究,但是鲜有针对城市或大范围内火灾风险评估方法的研究。本文综合考虑引发城市火灾的一些不确定影响因素,借鉴相应的城市火灾风险评价指标体系,应用模糊综合评价理论和方法,对城市火灾风险进行评价,为城市火灾风险提供一类有效的评价方法。最后给出的算例,表明本文提出的方法可行,具有较好的实际应用价值。 相似文献
85.
基于锥形量热仪试验的聚合物材料火灾危险评价研究 总被引:7,自引:0,他引:7
简述了锥形量热仪的试验原理,以聚合物材料锥形量热仪试验数据为基础,导出了火势增长指数(FGI)、放热指数(THRI6min)、发烟指数(TSPI6min)和毒性气体生成速率指数(ToxGI)4个评价聚合物材料火灾危险的参数,并利用这四个参数对ABS、PS、PVC、PA 4类16种商用塑料样品的火灾危险性逐项进行了分析评价.在此基础上,采用层次分析法的原理对样品的火灾危险进行了综合评价,结果表明,ABS、PS、PVC、PA四类样品的火灾综合危险依次减小. 相似文献
86.
社会需求与中国消防技术的发展 总被引:1,自引:0,他引:1
消防技术与社会之间是相互影响的关系,而“技术决定论”的理念只强调单方向作用,在“消防技术的社会形成”(SST)的视野中,重新审视中国消防技术的现状及未来,是更多地关注与技术决定论相反的研究进路。消防技术的社会需求是技术发展的纵向推动力,可以拉动消防技术的发展和进步。技术的形成和发展除具有自身逻辑发展的动力为还会受到社会因素的影响,因此技术的社会需求只说明有这种发展的可能,真正实现某一技术是一个很复杂的问题。但是通过政治、经济和文化三个层面分析社会需求对消防技术的发展起到的作用,在谋求自身逻辑发展与社会需求拉动结合推动中国消防技术时,仍然是很有启发性的。 相似文献
87.
88.
Silica particles of different physical properties (particle size, morphology and specific surface area) were introduced into an ethylene-vinyl acetate copolymer filled with an intumescent mineral fire retardant system containing magnesium hydroxide and organo-modified montmorillonites. The effect of silica particles on the cohesion and strength of the foamed combustion residue was studied by micro-indentation, concurrently with the characterization of material's fire behavior.Silica particles seem to act as defects that generate cracks, decreasing the strength of the residue. This generation of cracks is connected to a lower cohesion of the residue, especially for silica particles of high specific surface area. In parallel, the presence of silica of high specific surface area, despite tending to decrease Time To Ignition, also improves self-extinguishing ability, thanks to a better thermal stability at higher temperatures, and reduces the maximum Heat Release Rate in cone calorimeter tests. 相似文献
89.
We report the development of a capillary gas chromatographic method, superior to existing packed column methods, for the analysis of highly brominated additive fire-retardants, including decabromodiphenyl ether (1) and decabromodiphenoxyethane (II). Neither compound has been analyzed previously by capillary GC, and there are no published methods for (II). For (I), the new method is 5–10 times faster than an analogous packed column method, and it has 100 times lower detection limits and twice the precision of a gas chromatographic/mass spectrometric method. For (II), the capillary method is 30–50% faster than an unpublished liquid chromatographic method. The greater efficiency of the capillary method makes possible the complete resolution (R ≥ 1.25) of structurally very similar compounds (e.g. compound (II) and its Br9Cl1 and Br8Cl2 analogues). With the new method, commercial preparations of (I) and (II) can be rapidly analyzed, and samples from combustion and pyrolysis experiments can be evaluated for compositional changes. 相似文献
90.
H. -T. Chiu S. -H. Chiu R. -E. Jeng J. -S. Chung 《Polymer Degradation and Stability》2000,70(3):505-514
The thermal degradation and combustion behaviour of an interpenetrating network (IPN) structure of unsaturated polyester UP resin and a resole type of phenolic resin was studied. Thermal gravimetric analysis (TGA) was used to monitor the degree of thermal decomposition for the UP/phenol IPN structure and the change of the oxygen index (OI) was used to describe the variation of the combustion behaviour. The smoke density was measured via a non-flaming process to detect the amount of smoke generated during the combustion. A homemade cone calorimetric dynamic flammability evaluation system was assembled to analyse the gas evolved and to measure the heat release rate (HRR) during the combustion. Under simulated conditions of a burning field at the temperature of 757°C, the variation of the concentration of carbon monoxide (CO) and the HRR of the UP/phenol IPN structure were studied. The results show that modification of the essentially flammable UP resin by the phenol structure to form an IPN system cannot only remarkably improve the heat resistance but also help to suppress the smoke, toxic gas and heat release during the combustion. 相似文献