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21.
Yi‐Hung Chen Ching‐Yuan Chang Wei‐Ling Su Chun‐Yu Chiu Yue‐Hwa Yu Pen‐Chi Chiang Chiung‐Fen Chang Je‐Lueng Shie Chyow‐San Chiou Sally IM Chiang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(1):68-75
This study investigates the ozonation of CI Reactive Black 5 (RB5) by using the rotating packed bed (RPB) and completely stirred tank reactor (CSTR) as ozone contactors. The RPB, which provides high gravitational force by adjusting the rotational speed, was employed as a novel ozone contactor. The same ozone dosage was separately introduced into either the RPB or the CSTR for the investigation, while the experimental solution was continuously circulated within the apparatus consisting of the RPB and CSTR. The decolorization and mineralization efficiencies of RB5 in the course of ozonation are compared for these two methods. Moreover, the dissolved and off‐gas ozone concentrations were simultaneously monitored for the further analysis. As a result, the ozone mass transfer rate per unit volume of the RPB was significantly higher because of its higher mass transfer coefficient and gas–liquid concentration driving force. Furthermore, ozonation kinetics was found to be independent of the gravitational magnitude of an ozone gas–liquid contactor. Therefore, the results suggest employing RPBs as ozone‐contacting devices with the advantage of volume reduction. The experimental results, which can be used for further modeling of the ozonation process in the RPB, also show the requirement of correct design for the RPB. Consequently, the present study is useful for the understanding of practical application of RPBs. Copyright © 2004 Society of Chemical Industry 相似文献
22.
清代皇家园林规划设计控制的量化研究——以圆明三园、清漪园为例 总被引:1,自引:0,他引:1
本文通过量化分析探索了清代皇家园林规划设计的控制规律及相关理论。 相似文献
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部分种子成分的特征X射线在等效生物材料中衰减的测定 总被引:6,自引:5,他引:1
用Si(Li)探测器实现了Na、Mg、S、Cl的特征X射线在有机膜中的相对衰减以及与O、K元素的特征X射线能量相当的X射线或轫致辐射在有机膜中的相对衰减,分别得出了它们减的数学描述,并把实验得到不同能量的X射线在有机膜中的质量吸收系数与Berkeley的OCG软件计算出的结果相比,相关都小于30%。 相似文献
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The molecular mechanisms underlying the clustering and localization of K+ channels in specific microdomains on the neuronal surface are largely unknown. The Shaker subclass of voltage-gated K+ channel alpha-subunits interact through their cytoplasmic C-terminus with a family of membrane-associated putative guanylate kinases, including PSD-95 and SAP97. We show here that heterologous coexpression of either sap97 or PSD-95 with various Shaker-type subunits results in the coclustering of these proteins with the K+ channels. Mutation of the C-terminal sequence (-ETDV) of the Shaker subunit Kv1.4 abolishes its binding to, and prevents its clustering with, SAP97 and PSD-95. Whereas PSD-95 induces plaque-like clusters of K+ channels at the cell surface; however, SAP97 coexpression results in the formation of large round intracellular aggregates into which both SAP97 and the K+ channel proteins are colocalized. The efficiency of surface clustering by PSD-95 varies with different Shaker subunits: striking Kv1.4 clustering occurs in > 60% of cotransfected cells, whereas Kv1.1 and Kv1.2 form convincing clusters with PSD-95 only in approximately 10% of cells. 相似文献
29.
Li Xi Zuoyan Peng Wei Fan Kui Guo Gu Jianmin Muyu Zhao Wu Guoqiang 《Materials Science and Engineering: B》1996,40(2-3):147-152
SrMgxTi1 - xO3 nanocrystals (x = 0.1–0.6) were synthesized by the stearic acid gel method. Powder samples were characterized by X-ray diffraction and X-ray photoelectron (XP) spectroscopy. The results showed that the lattice parameter a and the O 1s XP spectrum changed not only with the Mg content x but also with the grain size d of the samples. The conductivity of a thick film specimen fabricated on an aluminium oxide wafer was investigated in a nitrogen—oxygen atmosphere. 相似文献
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