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51.
Flame structure and NO emission characteristics in counterflow diffusion flame of blended fuel of H2/CO2/Ar have been numerically simulated with detailed chemistry. The combination of H2, CO2 and Ar as fuel is selected to clearly display the contribution of hydrocarbon products to flame structure and NO emission characteristics due to the breakdown of CO2. A radiative heat loss term is involved to correctly describe the flame dynamics especially at low strain rates. The detailed chemistry adopts the reaction mechanism of GRI 2.11, which consists of 49 species and 279 elementary reactions. All mechanisms including thermal, NO2, N2O and Fenimore are taken into account to separately evaluate the effects of CO2 addition on NO emission characteristics. The increase of added CO2 quantity causes flame temperature to fall since at high strain rates a diluent effect is prevailing and at low strain rates the breakdown of CO2 produces relatively populous hydrocarbon products and thus the existence of hydrocarbon products inhibits chain branching. It is also found that the contribution of NO production by N2O and NO2 mechanisms are negligible and that thermal mechanism is concentrated on only the reaction zone. As strain rate and CO2 quantity increase, NO production is remarkably augmented. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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通过梳理管理学界对战略联盟的定义,发现价值链的鸸释同样适用于大学问的战略联盟。通过对已有的大学战略联盟的分析,提出了名校联盟与非名校联盟间的若干差异,最后提出了我国大学联盟战略的若干建议。 相似文献
55.
Biodiesel has become an attractive diesel fuel substitute due to its environmental benefits since it can be made from renewable resource. However, the high costs surrounding biodiesel production remains the main problem in making it competitive in the fuel market either as a blend or as a neat fuel. More than 80% of the production cost is associated with the feedstock itself and consequently, efforts are focused on developing technologies capable of using lower-cost feedstocks, such as recycled cooking oils and wastes from animal or vegetable oil processing operations. 相似文献
56.
C. Athanassiou G. Pekridis N. Kaklidis K. Kalimeri S. Vartzoka G. Marnellos 《International Journal of Hydrogen Energy》2007
In the present work, the prospects and trends of solid electrolyte membrane reactors (SEMRs) towards hydrogen production, are discussed. Initially, an overview of the principles, the properties and the techniques related to the usage of the SEMRs, are presented. In the following, a literature survey covering earlier and recent developments of the various methods (e.g. reforming or partial oxidation or dehydrogenation of hydrocarbons, steam electrolysis) employed in the SEMRs for the production of hydrogen, is performed. Finally, the current status of this research field is analyzed and future research topics are proposed. 相似文献
57.
合成氨催化剂的生产和技术 总被引:3,自引:0,他引:3
钱伯章 《精细石油化工进展》2003,4(11):28-34
介绍了世界合成氨催化剂发展历程、新开发的合成氨催化剂种类 ,同时评述了我国化肥催化剂研发和生产近况 ,对我国化肥催化剂性能进行了评价。 相似文献
58.
Esabi B Kurbanoglu 《Journal of the science of food and agriculture》2003,83(11):1134-1138
Production of the fungus Aspergillus niger NRRL 330 was studied in submerged fermentation with ram horn hydrolysate (RHH) as substrate. The characteristics of RHH have been reported previously. The RHH was enriched by addition of glucose and KH2PO4. The effects of kinetic parameters on the biomass yield of the fungus were investigated. The optimal conditions for growth of A niger on RHH were initial pH 6.5, temperature 30 °C, fermentation time 96 h and agitation speed 150 rpm. Under these optimal conditions the initial carbohydrate content of RHH was reduced from 1.52 to 0.2% and the biomass yield was 8.9 g l?1. The biomass contained about 48.1% protein, 5.2% fat and 9.4% ash (on a dry weight basis). The amino acid content of the biomass was compared with Food and Agricultural Organisation (FAO) and animal feed standards. The protein produced contained all the essential amino acids for animal feed, but the amounts of these amino acids were somewhat lower than those of FAO and soybean reference protein. However, the amino acid composition of the biomass was better than that of animal feed. The results with RHH were also compared with previously reported data on fungal mycelium grown on waste liquor substrate. In conclusion, it was found that RHH could be used as a substrate in the production of fungal protein for use as animal feed. Copyright © 2003 Society of Chemical Industry 相似文献
59.
M. A. Fatykhov 《High Temperature》2004,42(4):621-628
The paper gives the results of experimental investigations of the initial pressure gradient of bituminous oil and the time dependences of variation of the temperature in a formation model and of the well production rate in a microwave-frequency electromagnetic field. The effect of strong decay of the non-Newtonian properties of bituminous oil is revealed. The nonuniformity of temperature distribution over the formation thickness is demonstrated, which depends on the initial production rate of the well and on the duration of stimulation of the bottom-hole zone of formation. 相似文献
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