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71.
Liaqat A. Khan Edward A. Wicklein E. C. Teixeira 《Canadian Metallurgical Quarterly》2006,132(7):741-746
A three-dimensional (3D) computational fluid dynamics (CFD) model of a contact tank is presented in this paper. The model results are compared against 3D velocities and flow through curve (FTC) data, representing a tracer concentration profile, from a 1:8 scale physical model. The objective is to demonstrate that CFD models can simulate both the FTC and the 3D velocity field quite well. Simultaneous validation of velocities and FTC is important in ascertaining the predictive capabilities of CFD models, as physical model studies indicate that different baffle arrangements can lead to similar FTCs. Therefore, a good prediction of only FTC, as presented in previous 3D CFD model studies, does not necessarily imply a correct simulation of the flow field. 相似文献
72.
介绍龙滩水电站尾水出口工程枯期围堰的设计参数及计算过程,结合施工过程中的实际情况,总结得出土石子围堰的闭气方法和浆砌石主围堰堰体防渗的应注意几个问题。 相似文献
73.
To investigate the effects of multiple weak interactions on the binding of phenolic compounds by polymeric adsorbents, macroporous polystyrene (PS) resin and PS‐based adsorbents with different hydrogen‐bond acceptor atoms (PS CH2( OCH2CH2)n OCH3, n = 0, 1, 2, and 3, denoted as PS‐EG0, PS‐EG1, PS‐EG2, and PS‐EG3) were prepared. The phenol adsorption strength order on these adsorbents was PS/PS‐EG0 < PS‐EG1 < PS‐EG2 < PS‐EG3, indicating that the adsorption on PS and PS‐EG0 was driven by hydrophobic and π–π interactions, and the adsorption on PS‐EG1, PS‐EG2, and PS‐EG3 was driven by a hydrogen bond in addition to hydrophobic and π–π interactions. PS‐EG2 may adsorb a second phenol molecule on each binding site and PS‐EG3 may adsorb second and third ones. The adsorption strength of resorcinol increased in the order of PS, PS‐EG1, and PS‐EG2, indicating that the adsorption was driven by 0, 1, and 2 hydrogen bonds in addition to hydrophobic and π–π interactions. Similarly, the adsorption of phloroglucinol on PS, PS‐EG1, PS‐EG2, and PS‐EG3 was driven by 0, 1, 2, and 3 hydrogen bonds in addition to hydrophobic and π–π interactions because the adsorption strength increased in this order. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4652–4658, 2006 相似文献
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76.
正确处理三种关系,促进测量学教学健康发展--非测绘专业测量学的教学研究 总被引:5,自引:1,他引:4
结合教学实践,对如何正确处理好教学与科研、传统技术与新技术、传统教学与多媒体教学之间的关系进行了研究,并得出正确处理好这三种关系是促进测量学教学健康发展和提高教学质量的有效途径的结论。 相似文献
77.
茨21-133井CO2吞吐技术初步试验 总被引:1,自引:0,他引:1
茨榆坨油田茨13块原油属于普通稠油,1993年开始蒸汽吞吐采油,从第二轮开始效果明显变差,注汽返排率低,有效周期短,产量下降快,套管变形井增多。针对这些问题,在该区块茨21—133井进行CO2吞吐采油工艺现场试验,获得成功,增油效果明显。 相似文献
78.
稠油热采注汽管道由于长期在高温、高压下运行,极易发生各种损伤,如腐蚀、裂纹、材料退化等,极易造成管道承压能力降低,发生失效事故。如何检测出潜在危险性缺陷,判断注汽管道能否继续使用,是保证注汽管道安全运行的关键问题。探讨了高温压力管道在线检测技术发展现状及其应用范围。 相似文献
79.
The simultaneous contrast effect is investigated in this article. A total of 174 and 154 test/induction combinations were studied for CRT and surface colours respectively. Each combination was assessed by nine observers using a matching technique. The test and induction colours used for CRT colours were similar to surface colours using fabric samples. The results indicated a strong lightness contrast effect for both CRT and surface media; that is, the lightness of a test colour surrounded by a lighter induction colour was reduced for both CRT and surface colours. However, the effect in CRT medium was more pronounced than in the surface medium. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 13–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20074 相似文献
80.
Techniques and Apparatus for Measuring Rotational Core Losses of Soft Magnetic Materials 总被引:1,自引:0,他引:1
In many situations such as the cores of a rotating electrical machine and the T joints of a multiphase transformer, the local flux density varies with time in terms of both magnitude and direction, i.e. the flux density vector is rotating. Therefore, the magnetic properties of the core materials under the rotating flux density vector excitation should be properly measured, modeled and applied in the design and analysis of these electromagnetic devices. This paper presents an extensive review on the development of techniques and apparatus for measuring the rotational core losses of soft magnetic materials based on the experiences of various researchers in the last hundred years. 相似文献