The combustion （ballistic） properties of a high solid loading composite solid propellant family （Butalites） was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre...The combustion （ballistic） properties of a high solid loading composite solid propellant family （Butalites） was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre-polymer （HTPB） as a fuel binder main backbone, bimodal system ammonium perchlorate oxidizer （AP） and aluminum powder （AI） as metallic fuel. Burning rates were doubled at various pressures, when solids loading （AP and 17% A1） were increased from 80 to 88% and the measured characteristic velocity values were increased by about 100m/sec. The pressure exponent （n） values were lower with 80-85% solids loading. The burning rates were increased by about 2-5% when comparing the data obtained by static firing with those obtained by the strand burner method.展开更多
The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface metho...The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.展开更多
High inlet solid loading is one of the most important features of cyclone separators in high density circulating fluidized beds （CFB）. In this work, the effect of high solid loading on pressure drop in a reverse-flo...High inlet solid loading is one of the most important features of cyclone separators in high density circulating fluidized beds （CFB）. In this work, the effect of high solid loading on pressure drop in a reverse-flow cyclone was experimentally studied. The particles used were sand and 2zAl203. Art extended range of inlet solid loadings （M）, up to 30 kg of solids/kg of air was tested at different inlet air velocities （Vin=16~24 m/s）, well beyond the solid loading range reported before. The experiments showed that, in the tested range of solid loadings, the cyclone pressure drop decreased dramatically with increasing solid loading when M〈7.5 kg/kg and then almost remained constant. A new semi-empirical model for predicting cyclone pressure drop was also developed. The calculated and experimental results showed good agreement for particle free flow and particle laden flow.展开更多
文摘The combustion （ballistic） properties of a high solid loading composite solid propellant family （Butalites） was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre-polymer （HTPB） as a fuel binder main backbone, bimodal system ammonium perchlorate oxidizer （AP） and aluminum powder （AI） as metallic fuel. Burning rates were doubled at various pressures, when solids loading （AP and 17% A1） were increased from 80 to 88% and the measured characteristic velocity values were increased by about 100m/sec. The pressure exponent （n） values were lower with 80-85% solids loading. The burning rates were increased by about 2-5% when comparing the data obtained by static firing with those obtained by the strand burner method.
基金supported by Coordination for the Improvement of Higher Education Personnel Foundation,Mmistry of Education in Brazil(Grant No.POS-DOC-88881.170076/2018-01).
文摘The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.
基金supported by National High-tech Research and Development Program of China under Grant No.2006AA05A103
文摘High inlet solid loading is one of the most important features of cyclone separators in high density circulating fluidized beds （CFB）. In this work, the effect of high solid loading on pressure drop in a reverse-flow cyclone was experimentally studied. The particles used were sand and 2zAl203. Art extended range of inlet solid loadings （M）, up to 30 kg of solids/kg of air was tested at different inlet air velocities （Vin=16~24 m/s）, well beyond the solid loading range reported before. The experiments showed that, in the tested range of solid loadings, the cyclone pressure drop decreased dramatically with increasing solid loading when M〈7.5 kg/kg and then almost remained constant. A new semi-empirical model for predicting cyclone pressure drop was also developed. The calculated and experimental results showed good agreement for particle free flow and particle laden flow.
