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Michael N. Katehakis Ingram Olkin Sheldon M. Ross Jian Yang 《Annals of Operations Research》2013,208(1):5-26
This article provides a brief biographical synopsis of the life of Cyrus Derman and a comprehensive summary of his research. Professor Cyrus Derman was known among his friends as Cy. 相似文献
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Sheldon S.Q. Wu Thomas F. Soules Scott C. Mitchell Raymond J. Beach 《Optics Communications》2008,281(5):1222-1225
We report a demonstration of a 795-nm rubidium optical resonance transition laser using a buffer gas consisting of pure 3He. This follows our recent demonstration of a hydrocarbon-free 795-nm rubidium resonance laser which used naturally-occurring He as the buffer gas. Using He gas that is isotopically enriched with 3He yields enhanced mixing of the Rb fine-structure levels. This enables efficient lasing at reduced He buffer gas pressure, improved thermal management in high average power Rb lasers and enhanced power scaling potential of such systems. 相似文献
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Mazhar-Ul-Haque William Horne Sheldon E. Cremer James T. Most 《Journal of chemical crystallography》1989,19(2):317-329
The title compound crystallizes in the monoclinic space groupP21/n,a=13.429(3),b=18.248(6),c=14.497(4)Å,=90.61(2)°,Z=8, with two independent molecules in the asymmetric unit. The structure was solved by heavy-atom methods, and refined to a finalR value of 0.040. The phosphoranium ring adopts a chair conformation which is substantially flattened at the phosphorus end. The ring conformation and torsion angles are compared with similar compounds. 相似文献
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Motivated by the recent discovery of unusual "hydrogen bonding"-like interaction between a borane system and benzene molecules in a molecular crystal, we carried out quantum mechanical calculations on a model complex, diborane-benzene cluster. The aim is to understand the nature of this unique interaction, which is expected to play an essential role in this novel class of molecular crystals. As analyzed in the present study, the interaction between diborane and benzene is special in the following aspects: (1) this interaction is mostly dispersive; (2) the observed pseudodirectionality with one of the diborane bridge hydrogen directed toward the benzene centroid minimizes the van der Waals contact; and (3) in the "hydrogen bond" map, this interaction is located in a unique region, which is presently populated by a few known molecular complexes with very different chemical characteristics. It is anticipated that the results from the present analysis will provide meaningful guidance for molecular engineering with diborane-benzene as a building block and for stabilization of this and possible other hydrogen bonds by dispersive contributions. 相似文献
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