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Physics of the Solid State - Al-doped single wall carbon nanotube with Stone Wales defect was theoretically analyzed, two different orientations of chiral (8, 4) carbon nanotubes was doped among... 相似文献
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de Meijere A Nüske H Es-Sayed M Labahn T Schroen M Bräse S 《Angewandte Chemie (International ed. in English)》1999,38(24):3669-3672
Up to nine C-C bonds are formed selectively from up to seven components starting from an alkene, a haloarene, and a dienophile [Eq. (1)]. A comparison of liquid- and solid-phase reactions reveals a surprising superiority of the solid-phase reaction. 相似文献
45.
Mazen M. Abu-Khader 《Heat and Mass Transfer》2006,43(2):123-134
Tube inserts are used as heat transfer enhancement tool for both retrofit and new design of shell and tube heat exchangers. This paper discusses and reviews the characteristics and performance of twisted tapes. The theory and application are also addressed. Industrial case study was selected to illustrate the behaviour effect that the twisted tapes impose at various laminar, transition and turbulent flow regions. This effect was demonstrated by changing the inside tube diameter and twist ratio through evaluating selected exchanger design parameters such as: local heat transfer coefficient, friction factor and pressure drop. Testing the exponent powers for Re and Pr at both laminar and turbulent regions were carried out. General design considerations are outlined for the use of twisted tapes in shell and tube heat exchangers. 相似文献
46.
Journal of Computer-Aided Molecular Design - Zinc finger proteins (ZFP) play important roles in cellular processes. The DNA binding region of ZFP consists of 3 zinc finger DNA binding domains... 相似文献
47.
Mazen K. Nazal Mohammed A. Albayyari Fawwaz I. Khalili Ehsan Asoudani 《Journal of Radioanalytical and Nuclear Chemistry》2017,312(1):133-139
Importance of removal of radioactive elements from wastewater was the motivation behind this work. Synergistic solvent extraction of U(VI) and Th(IV) ions from perchlorate solution using didodecylphosphoric acid (HDDPA) incorporated with tri-n-butyl phosphate (TBP) or tri-n-octylphosphine oxide (TOPO) as a synergists have been studied for the first time. The effects of HDDPA concentration, synergist’s concentration, pH values and temperature on the extraction process have been studied. The thermodynamic parameters of the extraction process for these ions were calculated. It was found that the synergistic contribution of TOPO is higher than TBP in the extraction of Th(IV) and U(VI). 相似文献
48.
Msharrafieh M Al-Ghoul M Batlouni H Sultan R 《The journal of physical chemistry. A》2007,111(30):6967-6976
This paper is a study of the composition dynamics of Liesegang band strata of Co(OH)2 and Ni(OH)2 from NH4OH, with redissolution by complex formation with ammonia. At a fixed time, the cobalt hydroxide composition was found to exhibit a random variation with band number, yet within a general overall decrease. The decrease with band number becomes more pronounced as the initial concentrations of Co2+ and Ni2+ get closer to each other. At equal concentrations, periodic oscillations in Co(OH)2 composition appear over consecutive bands. The time evolution of the total Co(OH)2 mass percent (over the entire pattern of strata) passes through a maximum. The dynamics of this complex system has been simulated by theoretical calculations using the model of Müller and Polezhaev, modified by Al-Ghoul and Sultan in a series of two papers in J. Phys. Chem. A; the present paper is the third in the series. The simulations capture the essential features of the experimentally observed dynamics. 相似文献
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In this article, an algorithm for the numerical approximation of two-phase flow in porous media by adaptive mesh is presented. A convergent and conservative finite volume scheme for an elliptic equation is proposed, together with the finite difference schemes, upwind and MUSCL, for a hyperbolic equation on grids with local refinement. Hence, an IMPES method is applied in an adaptive composite grid to track the front of a moving solution. An object-oriented programmation technique is used. The computational results for different examples illustrate the efficiency of the proposed algorithm. © 1997 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 13: 673–697, 1997 相似文献