火焰原子吸收测定固体废物浸出液中锌、镍和铜

采用硫酸硝酸浸提、火焰原子吸收分光光度法测定催化剂固体废弃物中的锌、镍和铜3种元素,加标回收率为93．2—108．5％,相对标准偏差为0．4—1．7％。结果表明,该方法具有检出限低,重现性好、分析效率高、操作简便等优点。     

无卤阻燃剂的研究开发进展

介绍了塑料阻燃剂的种类以及阻燃技术的发展新动向,其中无卤、高效、低烟、低毒、多功能的新型阻燃剂是今后的发展方向。     

纳米锡酸锌/ABS/PVO复合材料阻燃性能研究

采用熔融共混法制备了纳米锡酸锌/丙烯腈-丁二烯-苯乙烯共聚物(ABS)/聚氯乙烯(PVC)复合材料。并对复合材料的冲击强度、阻燃性能进行了测试。结果表明,纳米锡酸锌不但可以提高复合材料的缺口冲击强度,还可以改善复合材料的抑烟阻燃性能。特别是当纳米锡酸锌添加量为6份时,复合材料的阻燃抑烟性能最佳。与未添加纳米填料时相比,纳米锡酸锌/ABS/PVC复合材料的缺口冲击强度达到69．93 kJ/m~2,提高幅度达49．71%。扫描电镜(SEM)分析表明,当纳米锡酸锌在6份时,其在复合材料中呈纳米级分散,且与塑料基体结合良好。     

基于环三磷腈磷氮阻燃剂的合成及其在聚氨酯泡沫的应用

以六氯环三磷腈、对羟基苯甲醛、苯胺及亚磷酸二乙酯等原料,成功合成阻燃剂六（4-苯胺基次甲基苯氧基-亚磷酸二乙酯基）环三磷腈（HADPPCP）,用于阻燃基于苹果酸多元醇的聚氨酯硬泡。HADPPCP具有良好的热稳定性和成炭性,氮气气氛下的初始分解温度为191.9℃,700℃时的残炭量高到46.8%（质量）。HADPPCP的加入可以改善聚氨酯硬泡的热稳定性、阻燃性能和燃烧行为。添加25%(质量)的HADPPCP可以将聚氨酯泡沫的氧指数从18%提高到25%,最大热释放速率和总热释放量分别从230 kW/m²和20.1 MJ/m²降低至213 kW/m²和16.6 MJ/m²,总产烟量从10.5 m²下降到5.3 m²。     

磷酸乙基新戊二醇酯的合成以及阻燃性能测试

以新戊二醇、三氯氧磷、乙醇为原料合成一种阻燃剂磷酸乙基新戊二醇酯（化合物Ⅱ），采用傅里叶变换红外光谱(IR)、核磁共振波谱(1HNMR、13CNMR及31PNMR)、液相色谱-质谱(ESI-MS)表征其化学结构。考察了物质的量比〔n(新戊二醇磷酰氯):n(乙醇)〕、反应温度和反应时间等因素对反应的影响，得到最佳反应条件为：n(新戊二醇磷酰氯) : n(乙醇)= 1.0 : 5.0，反应温度为50℃，反应时间为8 h，产率达80.8%。将合成的阻燃剂磷酸乙基新戊二醇酯添加到硬质聚氨酯泡沫(RPUF)中，通过极限氧指数(LOI)、垂直燃烧(UL-94)实验测定RPUF的阻燃性能，以及利用热重分析(TGA)表征阻燃剂和RPUF的热稳定性。结果表明，磷酸乙基新戊二醇酯的添加，在一定程度上降低了RPUF的热稳定性，但是RPUF的阻燃性能有所提高。添加量为30%(质量分数，以材料总质量计)时可使RPUF的LOI值从17.1提高到22.5%，通过垂直燃烧V-2级，以及在800℃时，残余残炭量由15.8%增加到18.9%。     

AHP/碱木质素聚氨酯泡沫的阻燃性能

对精制后的碱木质素进行羟甲基化改性,再利用改性后的羟甲基化碱木质素部分替代聚醚多元醇,采用一步发泡法与聚合MDI制备了羟甲基化木质素基聚氨酯泡沫材料。将次磷酸铝(AHP)作为阻燃剂添加到泡沫中制备了阻燃碱木质素聚氨酯泡沫,通过极限氧指数(LOI)测试分析了羟甲基化木质素基阻燃聚氨酯泡沫的阻燃性能。利用热重分析(TG)和扫描电子显微镜(SEM)分别研究制得泡沫的热降解行为、成炭性能和残炭形貌。实验结果表明,当羟甲基化碱木质素替代聚醚多元醇的量为60%,次磷酸铝的添加量为30%时,碱木质素聚氨酯泡沫材料的极限氧指数(LOI)值达到了27.5%。因此,羟甲基化碱木质素和次磷酸铝使泡沫在燃烧时能更好的形成炭层,从而有效地隔绝空气,降低热传递,提高了材料的阻燃性能。     

PVAc/OMMT纳米复合物的制备及其在阻燃PP中的应用

通过原位乳液插层法制备了有机蒙脱土(OMMT)含量较高的聚醋酸乙烯酯/有机蒙脱土(PVAc/OMMT)纳米复合物,并将其作为阻燃母料与氢氧化镁(MH)复配,与聚丙烯(PP)熔融共混制备了性能良好的无卤阻燃PP,用X射线衍射(XRD)、锥形量热分析(CONE)等对材料进行了表征。结果表明:当OMMT和MH的用量分别为3%和40%时,阻燃PP的热释放速率峰值(PHRR)相比于基体树脂从929.0kW/m2降低至193.7kW/m2,总释放热(THR)从165.2MJ/m2降低到73.6MJ/m2。     

Experimental determination of laminar burning velocities and Markstein lengths for 75% hydrous-ethanol, hydrogen and air gaseous mixtures

Hydrogen-rich mixtures generated by the on-board reforming of biomass-derived hydrous-ethanol can be used as a potential alternative fuel (i.e., reformed ethanol fuel, RE fuel). In this paper, outwardly propagating spherical flames were employed to observe the laminar flame characteristics of the gaseous mixtures composed of simulated RE fuel (mixture of 75% hydrous-ethanol and hydrogen) and air in a constant-volume combustion vessel at an initial temperature of 383 K, a pressure of 0.1 MPa, a hydrogen fraction from 0% to 80%, and an equivalence ratio from 0.6 to 1.6. The results show that the unstretched flame propagation speeds and burning velocities increase with increasing hydrogen fraction, especially when the fraction is above 40%. When the hydrogen fraction is less than 40%, the Markstein length and flame instability decrease and increase with the equivalence ratio, respectively, while the reverse holds when the hydrogen fraction is greater than 40%. At an equivalence ratio below 1.4, the Markstein length decreases with increasing hydrogen fraction, indicating a positive correlation between the flame instability and hydrogen fraction. At an equivalence ratio above 1.4, a negative relationship is observed. Finally, it is concluded that a hydrogen fraction of approximately 40% in simulated RE fuel is feasible for spark ignition engines by comparing the laminar burning characteristics of ethanol-air mixtures.     

煤粉复合旋流火焰燃烧特性研究（1）：实验研究

本文实验研究了煤粉复合旋流火焰燃烧特性，进行了包括３个典型煤种：褐煤、烟煤和无烟煤，在不同煤粉浓度下的燃烧试验，测量了火焰场的温度分布、气体组份分布、火焰周界辐射和煤颗粒燃烧参数，对火焰场特性、不同煤种影响和煤粉浓度作用做了较系统的试验研究，揭示了该燃烧方式的稳定着火、强化燃烧机理，获得了这种煤粉火焰的燃烧特性。     

Chemical kinetic study of a novel lignocellulosic biofuel: Di-n-butyl ether oxidation in a laminar flow reactor and flames

The combustion characteristics of promising alternative fuels have been studied extensively in the recent years. Nevertheless, the pyrolysis and oxidation kinetics for many oxygenated fuels are not well characterized compared to those of hydrocarbons. In the present investigation, the first chemical kinetic study of a long-chain linear symmetric ether, di-n-butyl ether (DBE), is presented and a detailed reaction model is developed. DBE has been identified recently as a candidate biofuel produced from lignocellulosic biomass. The model includes both high temperature and low temperature reaction pathways with reaction rates generated using appropriate rate rules. In addition, experimental studies on fundamental combustion characteristics, such as ignition delay times and laminar flame speeds have been performed. A laminar flow reactor was used to determine the ignition delay times of lean and stoichiometric DBE/air mixtures. The laminar flame speeds of DBE/air mixtures were measured in the stagnation flame configuration for a wide rage of equivalence ratios at atmospheric pressure and an unburned reactant temperature of 373 K. All experimental data were modeled using the present kinetic model. The agreement between measured and computed results is satisfactory, and the model was used to elucidate the oxidation pathways of DBE. The dissociation of keto-hydroperoxides, leading to radical chain branching was found to dominate the ignition of DBE in the low temperature regime. The results of the present numerical and experimental study of the oxidation of di-n-butyl ether provide a good basis for further investigation of long chain linear and branched ethers.