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51.
A nonstationary model of SO2 absorption from a gas phase to a countercurrent falling film of absorbing slurry was developed. Laminar, wavy and turbulent film structures were considered based on published information. Resistances to the mass transfer on the gas and the liquid sides of the interphase were considered, together with chemical reactions in the liquid phase. Relevant chemical equilibria in the liquid phase were modeled. Original experimental data on the neutralization reagent dissolution rate presented as a polydispersed two‐phase system of solids and on the rate of dissolved sulfite oxidation were used. The model was verified with experimental data from a laboratory‐scale falling‐film absorber using a single vertical tube under various geometrical and operating conditions, and a very good agreement was found with the experiment. Parametric sensitivity analysis showed the critical parts of the model.  相似文献   
52.
塔里木油田水碳酸盐平衡系数与有机酸的意义   总被引:3,自引:2,他引:1  
李伟  刘宝珺  闵磊 《石油学报》2003,24(5):32-35
根据统计学规律,对塔里木盆地油田水进行了研究,阐明了该盆地油田水的碳酸盐平衡系数(简称为RC)与有机酸的基本特征。从油田水的无机组分与有机组分的统计分析中发现了油田水的碳酸盐平衡系数与有机酸存在明显的负相关性,进一步论证了碳酸盐平衡系数和有机酸与油气聚集及油气性质的关系。碳酸盐平衡系数越低及低碳有机酸的含量越高,它们与油藏,尤其是与 轻质油或气藏的关系越密切。从两者的关系中初步了解到有机酸的溶蚀作用对油气藏中储层次生孔隙的形成应有较重要的影响。  相似文献   
53.
Polymer networks in which poly(propylene imine) dendrimers (Astramol?) are connected to each other by linear polytetrahydrofuran (polyTHF) segments, were prepared by two methods. The first method was a one‐step procedure in which bifunctionally living polyTHF, obtained by initiation of the THF polymerization with trifluoromethane sulfonic anhydride (triflic anhydride), was reacted with an amino‐dendrimer. This reaction was very fast but did not allow formation of the end products. The second method was a two‐step procedure. In a first step, living polyTHF, prepared with acryloyloxybutyl triflate as initiator, was grafted on an amino‐dendrimer, to form a star‐like, acrylate‐terminated polyTHF multi‐macromonomer with the dendrimer as core. In a second step, networks were obtained by Michael addition between the acrylate end‐groups and unreacted amino‐groups of the dendrimer. This cross‐linking reaction occurred spontaneously upon heating of the solution of the multi‐macromonomer with gelation times varying from a few minutes to a few hours, depending on the temperature and the composition of the prepolymers. With this method it was possible to prepare networks in the form of coatings or films. © 2003 Society of Chemical Industry  相似文献   
54.
The introduction of wavelength converters in wavelength division multiplexing (WDM) networks can reduce the blocking probabilities of calls. In this paper, we study the problem of placing a given number of converters in a general topology WDM network such that the overall system blocking probability is minimized. The original contributions of this work are the following: 1) formulation of success probability in a network as a polynomial function of the locations of converters; 2) proposal of an optimization model of the converter placement problem as the minimization of a polynomial function of 0-1 variables under a linear constraint, so that standard optimization tools can be employed to solve the problem; and 3) design of a search algorithm that can efficiently find the optimal solution to the converter placement problem. Experiments have been conducted to demonstrate the effectiveness of the proposed model and the efficiency of the algorithm.  相似文献   
55.
温州市龙湾段标准堤地基土中普遍存在一层海积淤泥,其强度低,压缩性高,承载力低,不能满足标准堤填筑及水闸运行的要求。采用预压法进行地基处理,取得的地基沉降、水平位移、孔隙水压力等现场观测资料,总结分析了该段海积淤泥地基的变形规律和特点。并提供了有关的原型观测数据,其沉降曲线规律性较好。  相似文献   
56.
Identification of anthocyanins in the wine made of the Croatian autochthonous grape variety of Babić (Vitis vinifera L.) was carried out and their profile was determined by means of high-performance liquid chromatography with diode array and mass spectrometric detection. Dependence of anthocyanins content and profile on maceration treatment conditions was investigated. Statistically significant differences of anthocyanins concentration in wines Babić produced by various maceration treatments were confirmed by the use of multivariate analysis of variances. The investigation results indicated that the maceration temperature exerts higher influence on anthocyanins concentration than the duration of maceration. In addition, on the basis of anthocyanin composition and using different multivariate statistical analyses, differentiation of wines Babić according to maceration treatments was procured.  相似文献   
57.
58.
研究了垂直腔面发射激光器 (VCSEL)及其列阵器件的光谱特性、调制特性、高频特性及与微电子电路的兼容性 ,将 1× 16的VCSEL与CMOS专用集成电路进行多芯片组装 (MCM ) ,混合集成为 16信道VCSEL光发射功能模块 .测试过程中 ,功能模块的光电特性及其均匀性良好 ,测量的 - 3dB频带宽度大于 2GHz.  相似文献   
59.
微机械可调谐滤波器的研制   总被引:6,自引:4,他引:2  
利用 Ga As/Al Ga As分布反馈 Bragg反射镜在 Ga As衬底上制作了一个微机械的调谐滤波器 .该器件在 7V调谐电压下调谐范围达28nm  相似文献   
60.
研究了微波干燥在气相超稳Y型分子筛制备中的应用。结果表明,分子筛经微波干燥后,其理化性质有所改善,结晶度提高,经气相超稳化反应后其产品结构及物化性质与传统电加热干燥后的气相超稳产品基本一致,说明微波干燥可替代传统干燥方式。与传统电加热干燥方式相比,微波干燥能缩短干燥时间,有效降低能耗。  相似文献   
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