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991.
大颗粒煤燃烧传递动力学破碎理论模型 总被引:4,自引:2,他引:4
研究了大颗粒煤燃烧中的颗粒破碎现象,理论分析了大颗粒煤的着火过程和颗粒破碎过程,建立了大颗粒煤燃烧传递动力学破碎模型,对褐煤、烟煤和无烟煤三个典型煤种进行了燃烧初期数值模拟,指出了大颗粒煤燃烧时着火和颗粒破碎的内在联系。 相似文献
992.
993.
Langmuir吸附方程的应用 总被引:2,自引:0,他引:2
本文总结了Langmuir方程在吸附分离过程中的应用。利用Langmuir方程得到直观表达混合气组分气体间吸附强弱关系及分离的难易程度的x-y图,推导了Lewis关系式。 相似文献
994.
A graft copolymer of 2-vinylnaphthalene (2-VN) and methyl methacrylate (MMA) onto ethylene–propylene–diene terpolymer (EPDM) was synthesized in tetrahydrofuran using benzoyl peroxide. The effects of EPDM content, and ratio of 2-VN to MMA, reaction time, reaction temperature, and initiator concentration in the graft copolymerization were examined. The light resistance, thermal stability, and the tensile properties of the graft copolymer were investigated by using Fade-o-Meter, thermogravimetric analyzer, and tensile tester. It was found that the light resitance and the heat resistance as well as the tensile strength of the graft copolymer are considerably better than those of the acrylonitrile–butadiene–styrene (ABS) copolymer. © 1994 John Wiley & Sons, Inc. 相似文献
995.
从油井的油层水中筛选到一株利用原油为碳源生长的芽孢杆菌M-l,当将其应用于石油污水处理时,在接种量为10%的条件下,能将污水的CODCr降低70%左右。当在污水中加入质量浓度为lg/L的(NIH4)2SO4时,能使M-l对污水CODCr的去除率达到80%以上。M-1在室内条件下最适处理污水的温度为45℃。利用固定化的M-1也可以使加入(NH4)2SO4污水的CODCr降低70%。经M-l处理后的污水在210~300nm范围内的光吸收明显降低。因此,M-l在石油污水处理中有很好的应用潜力。 相似文献
996.
997.
Polymethylphenylsilsesquioxane (PMPSQ–OH) and trimethylsilyl end‐blocked PMPSQ (PMPSQ–EC) were prepared. The thermal decomposition behavior of these polymers was studied by thermogravimetric analysis (TGA) and FT‐Raman spectroscopy. Hydroxyl‐functionalized polystyrene (PS–OH) was also prepared by anionic living polymerization. Thin hybrid films of PMPSQ/PS–OH with various blend ratios were obtained by spin‐coating on freshly cleaned glass. The surface morphology of the hybrid films was investigated by atomic force microscopy (AFM). In 80/20 PMPSQ/PS–OH hybrid film, the PS–OH component produced a very uniformly dispersed phase. This hybrid film contained small domains of PS–OH whose size ranged from 60 to 80 nm. As the content of PS–OH was increased, the domain morphology coarsened and phase inversion took place around 50 wt %. In the phase‐inversed system, the PMPSQ‐rich phase was uniformly distributed in the PS–OH‐rich continuous phase. In addition, temperature‐dependent dielectric properties of PMPSQ/PS–OH hybrids were investigated. Relaxation of the hybrids was observed with an increasing content of the PS–OH component due to the amorphous glass transition behavior of PS–OH. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2801–2812, 2003 相似文献
998.
999.
1000.
C. C. Young 《Journal of the American Oil Chemists' Society》1984,61(3):576-581
A new approach to interpret triglyceride data obtained by gas liquid chromatography (GLC) in order to determine cocoa butter
equivalents (CBE) in chocolate is described. The approach is based on the known straight line relationship which exists between
the C50 and C54 triglycerides of cocoa butter of different origins and the realization that, for currently available CBE conforming to CAOBISCO’s
criteria, a similar band relationship exists. The technique described enables the quantity of unspecified CBE in a chocolate
containing an unknown cocoa butter to be determined to an accuracy of ±1.5% when present in chocolate at the 5% level. Nut
oils (almond, walnut or hazelnut) are sometimes present in mainland European chocolates and, should CBE also be present, it
is possible to calculate the combined percentages of nut oil and CBE in the chocolate. The method of interpretation described
is not dependent on a particular GLC technique for determining triglycerides. Interpretation of other laboratories’ results
obtained using different GLC instruments and procedures has shown that the method enables any CBE present in the fat under
examination to be determined accurately. The method compensates for variations in the composition of CBE and for the differences
between cocoa butters of different origin. A detailed knowledge of CBE compositions is not required and only a few cocoa butter/CBE
standards are necessary. The method described is graphical, enabling small laboratories not equipped with microcomputers to
utilize the method. The calculation can, however, be programmed for a computer. 相似文献