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91.
Vibro-fluidized beds are widely used in drying sticky powders and agglomerated materials as milk powder. Using a vibro-fluidized laboratory scale dryer, this work is aiming at analyzing preliminarily the effect of its operational variables on the drying kinetics and characteristics of whole milk powder. The full-factorial design technique with three replications at the central point has been employed to generate data and correlations to quantify the effect of inlet air temperature, air flow rate, and vibration bed amplitude on the drying curves and the milk powder properties related to its faster reconstitution in water (as tapped density, Hausner cohesion ratio, agglomerate size distribution, and internal pore concentration). Results obtained are analyzed and discussed to identify the adequate operation condition for final drying whole milk powder in vibro-fluidized beds, assuring a high product quality.  相似文献   
92.
对比了典型进口及国产粉末喷涂设备对过喷粉末的利用情况,介绍了一种获得实用新型专利权的涂装装置。该装置综合了进口及国产设备的优点,具有很高的性价比。  相似文献   
93.
华北油田泥灰岩储层曾进行多种类型的酸化增产改造工艺,但均未取得理想效果。经过对泥灰岩地层进行大量的油藏地质、室内试验研究以及工程、地质技术人员的反复论证,优选出一种切实可行的酸压改造措施——前置液+高温乳化酸+固体硝酸酸压工艺。经过现场应用,收到了较好的增产效果,为华北油田泥灰岩储层改造措施找到了突破口。  相似文献   
94.
一种制备磁性粉末的新技术--均匀颗粒成型法   总被引:2,自引:0,他引:2  
采用均匀颗粒成型法(Uniform Dropler Spray-UDS)制备Fe基合金粉末,该方法制备的颗粒粒度分布均匀,性能一致,大大优于传统的粉末制备方法(如破碎法、气雾化),具有广阔的应用前景。本文分析了粉末制备过程中颗粒尺寸的影响因素,结果表明:颗粒的大小主要取决于坩埚底部小孔、坩埚内外气体压强差以及振荡频率三个独立变量。  相似文献   
95.
以多种含蜡馏分为基础原料,添加适量DT复合添加剂研制的DT型粉状炸药专用蜡具有优异的分散性和抗水性,可满足各种低梯粉状炸药要求,简化炸药配方,方便操作及其质量控制,以其生产的炸药爆速高,贮存期长,各项性能满足GB12437-2000标准要求。  相似文献   
96.
Porous NiTi shape memory alloy (SMA) is a novel biomedical material used for human hard tissue implant .The influence of elemental titanium powder characteristics such as powder morphology, particle size and specific surface area( SSA) on the minimal ignition temperature ,combustion temperature and final product of porous Ni-Ti SMA fabricated by combustion synthesis method was investigated in this paper by scanning electron microscopy (SEM) and laser diffraction.The preliminary data indicated that the titanium powder characteristics had a strong effect on combustion synthesis of porous NiTi SMA.  相似文献   
97.
硅粉/酚醛制备低成本碳化硅陶瓷复合材料   总被引:1,自引:0,他引:1  
以低成本的硅粉和酚醛为原料 ,采用浆料浸渍 热压成型 反应烧结法制备了Cf SiC单向板 ,并对工艺条件进行了探讨。制备得到的单向板的弯曲强度达到 45 6 .8MPa ,断裂韧性达到 7.94MPa·m1 2 。  相似文献   
98.
纳米NiO粉体的制备及其表征   总被引:4,自引:0,他引:4  
采用溶胶转化-凝胶法制备了纳米级NiO粉体。Ni(OH)2粉体的TG-DSC分析表明:在升温速率为10℃/min的条件下,粉体在489K时开始显著分解,626K时分解完毕。X-射线衍射分析表明:分解产物为纯净的NiO2。NiO粉体的化学成分分析表明:其纯度高于国家标准。TEM电镜分析表明:NiO粉体呈单分散的球形或棒状颗粒。对NiO粉体的热敏性能有待进一步研究。  相似文献   
99.
We have used x-ray phase analysis to study the composition of the products of reaction between oxygen and nanocrystalline powders with particle sizes 15, 40, 55, and 80 nm, and also specimens pressed (and sintered) from them. The powders were oxidized in air at 100°C (400 h) to 500°C (5 min), while the sintered specimens were oxidized at 600–900°C for 15, 120, and 240 min. In all cases, in the initial oxidation step the oxynitride Ti(OxNy) is formed, which over time is oxidized to TiO, Ti2O3, Ti3O5, TiO2 (anatase) and TiO2 (rutile). In the range 600–800°C, formation of a continuous oxide layer and conversion of anatase to rutile slows down diffusion of oxygen in the scale. We have established that at 900°C, the growth rate of the scale thickness increases and so the reflections from the oxynitride are barely noticeable on the diffraction patterns taken from the surface of the oxidized specimen. In these diffraction patterns, along with strong reflections from the rutile, we also observed weak reflections from lower oxides and anatase, which may be due to reaction between oxygen and the titanium ions diffused to the scale surface. We have concluded that at T > 850°C, the mechanism for oxidation of TiN changes. This is due to superposition of counterdiffusion of titanium ions on the diffusion of oxygen. __________ Translated from Poroshkovaya Metallurgiya, Nos. 3–4(448), pp. 72–78, March–April, 2006.  相似文献   
100.
The presence of protease inhibitors in soybean prohibits the utilisation of the raw beans for food and feed. However, little information is available about environmental influences and the effects of nitrogen and sulphur supply on the antinutritional constituents of soybean. As these factors may influence protease inhibitors, soybean genotypes segregated according to the presence or absence of the Kunitz trypsin inhibitor have been evaluated for trypsin inhibitor activity (TIA) in field trials. TIA was affected significantly by environment (geographical location), fertilisation treatment and genotype. Environmental means of TIA were between 69.5 and 104.8 mg g?1. Nitrogen application, which caused an increase in seed protein content, resulted in a reduction in TIA by about 15% as compared with the control. Remarkably, simultaneous application of nitrogen and sulphur in the form of ammonium sulphate had a similar reductive effect on TIA to that of nitrogen application alone, although soybean protease inhibitors are rich in sulphur amino acids. Significant genetic variation in TIA was found both within the genotype class with the Kunitz inhibitor present as well as within the class lacking this inhibitor. The results suggest that TIA of soybean may be modified considerably by genetic improvement and appropriate agronomic management. Copyright © 2003 Society of Chemical Industry  相似文献   
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