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231.
Computation of viscous fluid flow is an area of research where many authors have tried to present different numerical methods for solution of the Navier–Stokes equations. Each of these methods has its own advantages and weaknesses. In the meantime, many researchers have attempted to develop coupled numerical algorithms in order to save storage for computational purposes and to save computational time. 相似文献
232.
Parviz Rashidi-Ranjbar Ahmad Khoramabadi-zad Mahmood Roohi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):229-238
Abstract The conformation of the heterocyclic eight-membered ring in 16H-dinaphtho and 12H-dibenzo [d,g][1,3,2]dioxasilocine was investigated in solution by 1H NMR spectroscopy. The barrier to ring inversion in the 16H-dinaphtho compound 3a was found to be 8.6±0.2 Kcal/mol and for the 12 H-dibenzo compound 4a, 8±0.2 Kcal/mol. Molecular mechanics calculations show three energy minima conformations for both compounds, boat chair(BC), twist boat(TB) and twist boat boat(TBB). Twist boat form is estimated to be the global minimum for the dibenzo compounds while TBB is the global conformation of the dinaphtho compounds. The result of molecular mechanics calculations are supported by analysis of the 1H-NMR spectra. 相似文献
233.
Mohammad T. Baei Ali Reza Soltani Parviz Torabi Ali Varasteh Moradi 《Monatshefte für Chemie / Chemical Monthly》2011,51(12):979-984
Abstract
The behavior of the thiocyanate anion (SCN−) adsorbed on the external surface of H-capped (6,0), (7,0), (8,0), and Al-doped (6,0) zigzag single-walled carbon nanotubes was studied by using density functional calculations. Geometry optimizations were carried out at the B3LYP/6-31G* level of theory using the Gaussian 03 suite of programs. We present the nature of the SCN− interaction in selected sites of the nanotubes. Our results show that the pristine carbon nanotubes cannot significantly detect SCN−. The calculated binding energy of the Al-doped (6,0) single-walled carbon nanotubes indicated that SCN− can be adsorbed significantly on the C and Al sites and these nanotubes can therefore be used for SCN− storage. Binding energies corresponding to adsorption of SCN− on the Al site in the Al-doped (6,0) single-walled carbon nanotubes was calculated as −286.38 kJ mol−1. The calculated binding energies for SCN− in N-down orientation are higher than those in S-down orientation for all of the configurations. More efficient binding could not be achieved by increasing the nanotube diameter. We also report the effects of SCN− adsorption on the electronic properties of the nanotubes. 相似文献234.
Mohammad T. Baei Parviz Torabi Ali Varasteh Moradi Masoumeh Moghimi 《Monatshefte für Chemie / Chemical Monthly》2011,18(3):783-788