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171.
M. Zakaria 《Journal of Applied Mathematics and Computing》2002,10(1-2):175-191
The equations of a polar fluid of hydromagnetic fluctuating through a porous medium are cast into matrix form using the state space and Laplace transform techniques the resulting formlation is applied to a variety of problems. The solution to a problem of an electrically conducting polar fluid in the presence of a transverse magnetic field and to a probem for the flow between two parallel fixed plates is obtained. The inversion of the Laplace transforms, is carried out using a numerical approach. Numerical results for the velocity, angular velocity distribution and the induced magnetic field are given and illustrated graphically for each problems. 相似文献
172.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):683-686
The title compound, [Ni2(C8H4O4)(C10H24N4)2(H2O)2](ClO4)2, contains two independent octahedral NiII centres with trans‐NiN4O2 chromophores. The bridging benzenedicarboxylate ligand is bonded to the two Ni atoms, each via one O atom of each carboxylate, while the other O atom participates in an intramolecular N—H?O hydrogen bond, forming an S(6) motif. The cations are linked to the perchlorate anions via O—H?O and N—H?O hydrogen bonds [O?O 2.904 (6) and 2.898 (6) Å; O—H?O 158 (6) and 165 (6)°; N?O 3.175 (7) and 3.116 (7) Å; N—H?O 168 and 166°] to form molecular ladders. These ladders are linked by further O—H?O and N—H?O hydrogen bonds [O?O 2.717 (6) and 2.730 (5) Å; O—H?O 170 (4) and 163 (6)°; N?O 3.373 (7) and 3.253 (7) Å; N—H?O 163 and 167°] to form a continuous three‐dimensional framework. The perchlorate anions both participate in three hydrogen bonds, and both are thus fully ordered. 相似文献
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Carboxylation of ketones with carbon dioxide in the presence of magnesium chloride and triethylamine followed by reaction with methyl vinyl ketone gives satisfactory yields of Michael and Robinson annulation products. 相似文献