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91.
The effect of starch granule size on the viscosity of starch-filled poly(hydroxy ester ether) (PHEE) composites was characterized using size-fractionated potato starch, as well as unfractionated starches (rice, corn, wheat, and potato). Potato starch was separated using an air classifier into four particle size fractions: <18 m, 18-24 m, 24-30 m, and >30 m. The starch was dried to a moisture content of 0.5% to minimize moisture effects on composite rheology. PHEE and potato starch were extruded with starch volume fractions of 0.46 and 0.66. Stress relaxation, frequency and strain sweep, and temperature-dependence measurements were carried out. Although small variations in viscosity were seen with the different potato starch fractions, differences were not significant at a volume fraction of 0.46. Viscosity differences between the different particle size fractions were more pronounced at a volume fraction of 0.66. The temperature dependence could be described by an Arrhenius relation, with an apparent activation energy of 84 kJ/mole. At a volume fraction of 0.46, the starch/PHEE viscosities increased in the order potato starch < wheat starch corn starch < rice starch.  相似文献   
92.
介绍了某定向钻工程中黏土层、细砂中砂层、粉砂合砾地层泥浆的配制工艺及斜孔段、水平孔段、扩孔段、回拖段施工过程泥浆性能的调整方法。简述了该穿越工程泥浆的混配、回收及处理应注意的若干事项。实践表明,该水平定向钻穿越工程施工质量较好,其安全与环保工作也较为理想。  相似文献   
93.
在制备聚硅酸盐类混凝剂的过程中,聚硅酸的粘度是影响聚硅酸盐类混凝剂混凝效能的重要因素。以水玻璃为原料,硫酸、盐酸为酸化剂,采用酸性条件下制备聚硅酸的方法,研究pH值、二氧化硅浓度、温度、不同酸化剂等因素对硅酸聚合过程中粘度变化的影响,结果表明:粘度达到0.006 Pa.S前变化缓慢,粘度达到0.009 Pa.S后变化迅速,0.020 Pa.S以后在极短的时间内粘度急剧增大而胶凝;通过混凝搅拌实验确定制备聚硅酸铝混凝剂时聚硅酸粘度的最佳值,以此最佳值作为控制聚硅酸最佳聚合程度的指标。  相似文献   
94.
Sludge granulation and the effect of gas-liquid-solid separator (GLSS) design on the efficiency of upflow anaerobic sludge blanket (UASB) and upflow anaerobic sludge filter (UASF) reactors, operating at HRTs ranging from 3 to 12 h was investigated. VSS/TS ratio gradually increased in both the reactors with increasing sludge age (from 0.5 to more than 0.7 for UASB reactor and 0.012 to 0.043 for UASF reactor). X-Ray diffraction analysis of the UASF sludge showed the presence of expanding clays revealing its additional absorption capability. Fuoraphyllite and albite precipitation related to excellular polymers of the microbial shell structure, showed the extended growth of microorganisms during sludge granulation. A gradual decrease (82%-69%) in COD removal with decreasing HRT was apparent in UASF reactor. In case of UASB reactor, this decrease was marginal because addition of GLSS device significantly improved (14%-20%) the overall efficiency of the UASB reactor. GLSS enhanced the efficiency of the UASB reactor by increasing the settleability of suspended particles and accelerating the coagulation of colloidal particles due to the velocity gradient.  相似文献   
95.
柳钢采用氨-硫铵法脱除烧结机头烟气中的SO2,脱硫效率达95%。由于采用液氨作为脱硫剂,致使脱硫成本太高。为解决烧结烟气脱硫所需的氨源,大幅度降低治污成本,本次改造主要将焦化厂现有的氨回收硫铵工艺改造为氨水工艺,实现"以废治废"、脱硫、减硝、降尘、节能降耗的目的。  相似文献   
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