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To the flow produced in particle-suspension by a rotating disk of infinite extent,the asymptotic behavior at infinity is analyzed.A corresponding series solution is presented.It isshown that this approach yields widely valid solutions of high accuracy for all the cases in whichthat suction or weak injection at the disk surface exists.For the cases that strong injection or par-ticle-free band exists,the series method fails.  相似文献   
3.
本文介绍了InP、InGaAs、InGaP、InGaAsP等的光压港(PVS)。并把InGaAsP(在特定组份下)的PVS与FFT—PL谱进行了比较;分析和讨论了PVS测试的局限性和复杂性;指出了对多层异质结构材料,只有把器件结构、外延工艺、ECV测试等结合起来,才可能正确地理解PVS给出的测试结果。  相似文献   
4.
本文论述了黑釉铁锈花产品的坯釉料组成及制作工艺.井对黑釉铁锈花产品的起源、形成机理进行了探讨分析。  相似文献   
5.
Knowledge and Information Systems - Developing effective and efficient data stream classifiers is challenging for the machine learning community because of the dynamic nature of data streams. As a...  相似文献   
6.
Neural Computing and Applications - Cryptography often involves substituting (and converting) the secret information into dummy data so that it could reach the desired destination without leakage....  相似文献   
7.
This work has been concerned with the synthesis of the hydrogels of poly (vinyl pyrrolidone) (NVP), poly (hydroxy ethylmethacrylate) (HEMA), and their copolymer under the effect of gamma radiation in the presence of N,N‐methylenebisacryl‐amide (MBAm) as a crosslinking agent. The effect of the different factors that may affect the gelation and yield product, such as solvent composition and irradiation dose, was investigated. The formed hydrogels were characterized in terms of swelling in water and different organic solvents, X‐ray diffraction (XRD), and IR spectroscopic analysis. The sorption capability of these hydrogels towards some commercial basic and acid dyesstuffs was also studied. The results showed that a solvent mixture composed of equal contents of water and methanol is the most suitable to afford the minimum sol fraction and the highest yield product at a minimal irradiation dose of 10 kGy. It was observed that NVP hydrogel displayed the highest swelling in water, alcohols, and dimethyformamide of ~1300% and a lower tendency to swell in nonpolar solvents. The results showed that HEMA hydrogel has a high affinity to absorb basic dyes while NVP has a tendency for acid dyes. Also, the sorption of either the basic or acid dyes by the different hydrogels was found to greatly depend on the concentration of dye in solution and the mass of the used hydrogel. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3274–3280, 2004  相似文献   
8.
Miscible polymer blends based on various ratios of poly(vinyl acetate) (PVAc) and poly(methyl methacrylate) (PMMA) were prepared in film form by the solution casting technique using benzene as a common solvent. The thermal decomposition behavior of these blends and their individual homopolymers before and after γ‐irradiation at various doses (50–250 kGy) was investigated. The thermogravimetric analysis technique was utilized to determine the temperatures at which the maximum value of the rate of reaction (Tmax) occurs and the kinetic parameters of the thermal decomposition. The rate of reaction curves of the individual homopolymers or their blends before or after γ‐ irradiation displayed similar trends in which the Tmax corresponding to all polymers was found to exist in the same position but with different values. These findings and the visual observations of the blend solutions and the transparency of the films gave support to the complete miscibility of these blends. Three transitions were observed along the reaction rate versus temperature curves; the first was around 100–200°C with no defined Tmax, which may arise from the evaporation of the solvent. The second Tmax was in the 340–380°C range, which depended on the polymer blend and the γ‐irradiation condition. A third transition was seen in the rate of reaction curves only for pure PVAc and its blends with PMMA with ratios up to 50%, regardless of γ‐ irradiation. We concluded that γ‐irradiation improved the thermal stability of PVAc/PMMA blends, even though the PMMA polymer was degradable by γ irradiation. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1773–1780, 2006  相似文献   
9.
原矿含泥量大造成设备的堵塞。根据现场生产实际改用粉碎后的矿粒直接给入扇形孔条筛,筛下可调刮板使细粒均匀分布在皮带下面,粗粒复盖其上。物料到达皮带首轮处,使其呈抛掷状态,然后利用分离挡板除去细粒。首轮的直径和转速是按粒度分离的决定因素。分离细粒级后使中碎机生产能力增大,降低能耗,减少磨损,提高了设备运转率。  相似文献   
10.
负离子分解室内有机化合物的测试   总被引:3,自引:0,他引:3  
低浓度、高毒性的挥发性有机化合物(VOC)污染大气,造成“病态建筑综合症(SBS)”,严重威胁着人们的身体健康。空气中的负离子除有利于人体生理健康以外,还能有效分解空气中的VOC。将一种负离子添加剂添加到墙体涂料中,可以得到一种能有效释放负离子的涂料。本文测试了涂刷负离子添加剂涂料的测试小室中负离子分解总挥发性有机化合物(TVOC)及甲醛的性能,结果证明:涂料释放的负离子能有效分解VOC,使室内VOC的浓度在较短时间内满足GB/T—18883—2002的要求。  相似文献   
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