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231.
田聪  杨伟 《火灾科学》2012,21(1):28-34
首先合成并表征了一种新的阻燃剂-次磷酸铈(CHP);然后采用熔融共混的方法制备了玻璃纤维(GF)增强聚对苯二甲酸乙二醇酯(PET)/CHP(PET/GF/CHP)复合材料;探讨了CHP对PET/GF复合材料热稳定性和燃烧性能的影响。材料的热稳定性是由热失重分析(TGA)进行表征的,燃烧性能是通过氧指数(LOI)、垂直燃烧(UL-94)以及锥形量热仪进行测试的,炭渣形貌由扫描电子显微镜(SEM)进行表征。结果表明:CHP的引入保持了PET/GF的热稳定性。含有15wt%CHP的PET/GF材料(PET/GF/CHP15),其LOI为30%,且能达到UL-94V-0级别。此外,与PET/GF相比,PET/GF/CHP15热释放速率峰值和热释放总量分别下降了67%和27%。SEM分析表明CHP的加入使得材料在燃烧后有大量致密的炭渣覆盖在玻璃纤维的表面,这些炭渣不仅降低了玻璃纤维的导热性,而且切断了可燃物质的传送通道,从而提高了材料的阻燃性能。  相似文献   
232.
Coal spontaneous combustion is one of the major natural disasters faced in coal mines. The accurate prediction of the thermal risk of coal is of great importance. However, there isn't a widely accepted approach to get the oxidation process of coal that under adiabatic condition or in a specific environment under mine at present. To demonstrate whether the advanced kinetics simulation method could be employed to obtain the accurate oxidation process of coal for determining the coal's thermal risk in the mine design phase and mining phase, DSC experiments were conducted by C80 micro-calorimeter to get the heat behavior of coal, based on which the kinetic parameters can be solved and the oxidation process of coal can be predicted.The results showed that the kinetics based simulation method was successfully used to predict the adiabatic temperature rise process of coal for risk prediction. The deviation between the predicted curve and tested curve that obtained by adiabatic test is small enough to be accepted. Kinetics based simulation method is a promising candidate, instead of adiabatic test, to assess the propensity of coal to spontaneous combustion, which can play an important role in the design phase of the mine and mining area. Moreover, through establishing the heat balance equation of residual coal and with the aid of kinetics based simulation method, the oxidation process of coal that in the suffocation zone of the gob was also accurately predicted. According to the index t70 (the time required for coal to reach 70 °C) and vmin (the lower limit of the advancing speed of the working face) obtained from the predicted curve, the thermal risk of coal was predicted to guide the further adjustment of the advancing speed of the working face, the amount of the injected mud and the determination that whether to add other fire prevention measures. Kinetics based simulation method, be of great practical importance in risk prediction of coal that in the gob, can be also used as a convenient tool to guide the safe production in the actual mining process.  相似文献   
233.
The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency.  相似文献   
234.
The paper proposes a critical assessment of municipal solid waste gasification today, starting from basic aspects of the process (process types and steps, operating and performance parameters) and arriving to a comparative analysis of the reactors (fixed bed, fluidized bed, entrained bed, vertical shaft, moving grate furnace, rotary kiln, plasma reactor) as well as of the possible plant configurations (heat gasifier and power gasifier) and the environmental performances of the main commercially available gasifiers for municipal solid wastes. The analysis indicates that gasification is a technically viable option for the solid waste conversion, including residual waste from separate collection of municipal solid waste. It is able to meet existing emission limits and can have a remarkable effect on reduction of landfill disposal option.  相似文献   
235.
出舱活动过程中航天员的热舒适性分析   总被引:1,自引:0,他引:1  
分析了出舱活动中航天员- 服装系统的热平衡,阐述了影响航天员热舒适性的因素及热舒适性的评价标准,并对美国航天员舱外活动的冷应激的人体工程学问题进行了讨论。还指出了提高航天员热舒适性有待解决的几个关键问题。  相似文献   
236.
由丁二烯过氧化物引发的爆炸事故已受到社会的关注和重视 ,国内外一些学者针对丁二烯过氧化物的危险特性进行了一些研究工作 ,并取得了一定进展。但由于丁二烯过氧化物本身合成与测试的复杂性和危险性 ,深入而系统地研究丁二烯过氧化物的危险性及其机理显得十分必要 ,同时将面临重重困难。  相似文献   
237.
A mediation exercise to resolve the ongoing dispute against these power plant projects at Aliağa was recommended and participated in by the author in 1997. In this article the basis of the continuing environmental concern about the feared impacts of the new power plants, procedure, and results of this mediation are mentioned. The basis of the “energy versus environment” dispute in Aliağa are introduced. Mediation exercise and its end results have been criticized.  相似文献   
238.
寒冷地区人工湿地污水处理技术研究进展   总被引:4,自引:0,他引:4  
人工湿地作为我国新型的生态处理工艺,在寒冷地区的应用逐渐得到重视。本文总结了寒冷地区人工湿地的发展及应用情况,对湿地设计以及冬季保温措施进行了归纳与总结。  相似文献   
239.
In early 2011, the G-13 Silane Modeling Task Force of the Compressed Gas Association (CGA) proposed a series of tests to better define pyrophoric behavior during unintentional, large-scale releases of silane. The tests were conducted in two phases under the direction of CGA and its guidelines. Phase I took place from June 27 to June 30, 2011, focusing primarily on thermal radiation and the heat transfer from flame impingement due to silane release from a fully open pressure relief device (PRD) on a tonner. Phase II took place on June 19 and 20, 2012, focusing on thermal radiation and explosion overpressure. The results were subsequently utilized to revise CGA G-13 guidelines on the safe handling of silane. In the present two-part papers, the results from the tests are summarized in order to highlight the key findings. The first part of summary described the results of the flame impingement and thermal radiation tests. Three different test series were conducted, including shakedown tests using nitrogen instead of silane, silane flame-impingement tests onto an adjacent target tonner, and heat-flux tests. For comparison with known values in the published literature, thermal radiation of ethylene flame jets was also measured. In addition, metallurgical analyses of the target tonner indicated that the metallurgical properties of the cylinder material were not altered by the flame impingement. The steel surface temperature at the point of impingement was estimated to be below 853.15 K and definitely did not exceed 950.15 K. Thus, the combination of internal pressure and vessel metal temperature was unlikely to exceed the rupture pressure of the ton cylinder.  相似文献   
240.
对建筑中广泛使用的低压配电箱在实际火灾条件下的导热过程进行了分析,借鉴现有规范中对排烟风机的耐温要求,估算了配电箱在280℃时需要的隔热板厚度。在一腔室内利用火源功率为700kW的油池火模拟实际火灾环境,对普通配电箱和加隔热板配电箱箱体温升特性进行了研究,分析了火灾环境温度变化对配电箱箱体、内部温度变化的影响规律,验证了配电箱保持连续工作30min的耐火设计要求。  相似文献   
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