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441.
张波  曾文茹 《火灾科学》2014,23(4):233-237
合成并表征了石墨烯,然后通过溶剂法制备石墨烯/环氧树脂复合材料,研究了石墨烯对环氧树脂复合材料的热稳定性和燃烧性能的影响。热重分析数据显示,石墨烯可以显著提高环氧树脂的热稳定性。锥形量热仪测试结果表明,石墨烯降低了环氧复合材料热和烟气的释放。炭渣的扫描电镜(SEM)图揭示了石墨烯减少了环氧树脂炭层孔洞的生成,提高了炭层的致密度,从而增强了炭层的阻隔作用。  相似文献   
442.
仿真系统已成为工业锅炉操作人员培训的重要手段之一,在工业锅炉仿真系统中加入节能模块,能有效增强经济运行指导和提高操作人员节能意识。本文利用仿真开发平台SimuWorks构建工业锅炉仿真系统节能模块,通过锅炉正反平衡热效率公式分析及简化,给出了飞灰含碳量的直接计算方法,结合各模块计算数据,可以获得完整的运行经济指标。  相似文献   
443.
• Hydrothermal treatment can greatly improve resource recovery from sewage sludge. • tCOD removal during WO was ~55% compared with ~23% after TH. • TOC solubilization during hydrothermal treatment followed first-order kinetics. • Solids and carbon balance confirmed loss of organics during thermal hydrolysis. • Reaction pathways for thermal hydrolysis and wet oxidation are proposed. We evaluated the effect of hydrothermal pretreatments, i.e., thermal hydrolysis (TH) and wet oxidation (WO) on sewage sludge to promote resource recovery. The hydrothermal processes were performed under mild temperature conditions (140°C–180°C) in a high pressure reactor. The reaction in acidic environment (pH= 3.3) suppressed the formation of the color imparting undesirable Maillard’s compounds. The oxidative conditions resulted in higher volatile suspended solids (VSS) reduction (~90%) and chemical oxygen demand (COD) removal (~55%) whereas TH caused VSS and COD removals of ~65% and ~27%, respectively at a temperature of 180°C. During TH, the concentrations of carbohydrates and proteins in treated sludge were 400–1000 mg/L and 1500–2500 mg/L, respectively. Whereas, WO resulted in solids solubilization followed by oxidative degradation of organics into smaller molecular weight carboxylic acids such as acetic acid (~400–500 mg/L). Based on sludge transformation products generated during the hydrothermal pretreatments, simplified reaction pathways are predicted. Finally, the application of macromolecules (such as proteins), VFAs and nutrients present in the treated sludge are also discussed. The future study should focus on the development of economic recovery methods for various value-added compounds.  相似文献   
444.
Temperature-programmed pyrolysis mass spectrometry and Fourier-transform infrared spectroscopy have been used to monitor structural changes of humic and fulvic acids isolated from soils in China, in the temperature range of 25-550°C. in this work, we found that decarboxylation is obvious as the main reaction with dehydration reaction from 150°C to 400°C, the anhydride can be identified from FT-IR spectra at temperature range from 200°C to 400°C; there are evident changes of the aromatic nucleus of humic and fulvic acids above 400°C, even remaining up to 550°C. Besides, some changes of adsorption water can be distinguished before 200°C, and the mass signal of sulphur dioxide was detected.  相似文献   
445.
It has previously been shown that the level of Daphnia proteins detected by commonly used anti-HSP antibodies, with molecular weights corresponding to those of heat shock proteins, can be modified by various kinds of stress, including the threat of predation. In this study, we demonstrate for the first time that these proteins change their expression in response to thermal stress. Thus, it is concluded that Daphnia heat shock proteins, as components of the cellular stress defense, are involved in both, abiotic and biotic stress.  相似文献   
446.
本文针对局部火灾条件下钢结构屋架的防火保护问题,结合典型案例提出了一种基于性能计算分析的抗火保护设计评估分析方法.首先通过火灾场景分析及烟气运动模拟计算,得到钢结构屋架所处的热环境,再计算各构件在不同保护条件下的温升及应力分布,并判断构件及结构在不同的保护方式下是否失效,最后得到经济合理的保护区域和防火涂层厚度.该方法可以为类似的局部火灾条件下钢结构抗火保护提供参考.  相似文献   
447.
The Japanese Government introduced the Law on Recycling of End-of-Life Vehicles (ELV Recycling Law) in 2002. This law requires manufacturers to retrieve chlorofluorocarbons (CFCs), airbags, and automobile shredder residue (ASR) from ELVs and to properly recycle the remaining materials. This framework is compared with European ELV directives. Pilot-scale incineration plant testing has revealed a greater formation of by-product persistent organic pollutants (POPs) during the primary combustion of ASR compared to normal municipal solid waste. This may be attributed to the abundance of chlorine, Cu, and Fe in ASR, as Cu and Fe have been found to catalyze the formation of POPs under certain conditions. However, most by-product POPs were destroyed by the secondary combustion, and almost all were removed after flue gas treatment. The direct melting system is a shaft-type gasification and melting technology that has proved effective in many municipal solid waste applications. This system can be applied to ASR recycling for effective decomposition of brominated flame retardants and polybrominated dioxins.  相似文献   
448.
本文基于轴对称灰体火焰的物理假定,运用二维数值积分方法,对含水层油品燃烧过程反馈热辐射以及火焰对环境的热辐射水平进行了估算;同时,本文研究了火焰反馈热辐射对油品燃烧速率的影响,所得结果物理趋势合理。  相似文献   
449.
Mitigation of greenhouse gases by adoption of improved biomass cookstoves   总被引:1,自引:0,他引:1  
Greenhouse gases especially CO2 can be reduced with the help of improved biomass cookstoves. This paper deals with the design and development of biomass stoves (single pot and double pot) with better efficiency for meeting household cooking energy requirement. Thermal performance, flue gas emission of carbon monoxide (CO) and carbon dioxide (CO2) have been investigated. It was seen from the result that the flue gas emission is within permissible limit as recommended by World Health Organization. The design of improved biomass stove sent to Palampur (32o10’N,76o30’E) center situated in Himalaya in hilly terrain of India, where the acceptability of double pot stoves (85%) is quite high compared to single pot stoves (30%). Thermal efficiencies of both single and double pot stove were recorded about 21% and 25% respectively. An improved biomass cookstove can save about 161 kg of CO2 annually. Improved cookstoves was found eco-friendly in nature and suitable for the cooking requirement of hilly areas.  相似文献   
450.
对热脱附-气相色谱测定苯系物方法中的几种常用吸附剂进行了选择比较。结果表明,在测定苯、甲苯、乙苯、二甲苯以及苯乙烯时,TenaxTA/Carbograph1TD复合型吸附剂的综合吸附效率最好。TenaxTA/Carbograph1TD复合型吸附剂的检出限、精密度、准确度和保存期都得到了良好的结果,能够满足监测分析的要求。  相似文献   
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