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111.
Frontispiece: Reversible Mechanical Interlocking of D‐Shaped Molecular Karabiners bearing Coordination‐Bond Loaded Gates: Route to Self‐Assembled [2]Catenanes 下载免费PDF全文
112.
113.
114.
Madhuri T. PatilShobhana Krishnaswamy Manash P. Sarmah Mysore S. Shashidhar 《Tetrahedron letters》2011,52(29):3756-3758
A facile and high yielding synthesis of epi-inositol via stereoselective reduction of a pentaprotected epi-inosose is reported. Extent of stereoselectivity during the hydride reduction appears to depend on the ability of the substrate to complex with metal ions in the reducing agent. 相似文献
115.
Two-dimensional equations for coupled extensional and thickness-stretch waves in an elastic plate are simplified by eliminating the extensional displacements in a systematic manner; the result is a single equation governing thickness-stretch motions. A similar reduction is also performed for coupled extensional, thickness-stretch, and symmetric thickness-shear waves. The procedure is similar to that used in the thickness-shear approximation, wherein the flexural displacement is eliminated from the equations for coupled flexural and thickness-shear motions. The resulting equations are used to discuss the energy-trapped vibration of plates in thickness-stretch modes. 相似文献
116.
M.R. Krishnaswamy M.G.K. Menon N.K. Mondal V.S. Narasimham B.V. Sreekantan Y. Hayashi N. Ito S. Kawakami S. Miyake 《Physics letters. [Part B]》1982,115(4):349-358
Three events have been recorded in the Kolar Gold Field experiment with tracks fully confined to the detector volume. It is shown that their characteristics are in conformity with the decay of bound nucleons and that the background due to neutrino interactions is extremely small. Based on these as well as the events reported earlier, we tentatively suggest a mean lifetime of about 7 × 1030 yr for nucleons bound in iron nuclei. 相似文献
117.
L. W. Nicholson Krishnaswamy Rengan 《Journal of Radioanalytical and Nuclear Chemistry》1979,54(1-2):355-360
The level of arsenic in six different species of fish collected from Lake Michigan near Saugatuck, Michigan has been measured
using radiochemical neutron activation analysis. The arsenic concentration was found to vary from 0.05 μg/g (wet weight) for
yellow perch fillet to 1.4 μg/g (wet weight) for eviscerated bloater chubs. A significant correlation was observed between
arsenic concentrations and number of years in the lake for lake trout; correlations were also observed between arsenic concentrations
and length of lake trout and smelt. No such correlations were found for alewife or yellow perch. 相似文献
118.
Self-consistent-field and configuration-interaction studies were performed on borazine, using a double-zeta basis set augmented by six diffuse -functions. Low-lying singlet and triplet states of the A
1
, A
2
and E species were calculated, corresponding to * excited valence and Rydberg states. A selection out of singly and doubly excited configurations relative to a set of reference configurations was made for each species. Calculated vertical excitation energies (in eV) are 7.12 for 1
A
2(V), 8.45 for 1
E (3p-R), 8.57 for 1
A
1(V), 8.9 for 1
E(V-R), 9.55 for 1
E(3d-R), 6.98 for 3
A
1(V), 7.27 for 3
E(V), 7.82 for 3
A
2(V), 8.30 for 3
E(3p-R), and 9.5 for 3
E(3d-R), where V and R refer to valence or Rydberg character. The results are compared with experimental excitation energies, previous ab initio studies of borazine, and with recent ab initio studies of benzene.Dedicated to Professor Dr. H. Hartmann on the occasion of his 65th birthday. 相似文献
119.
beta-Diketiminato Cu(I)-lutidine complexes [RMeNN]Cu(2,4-lutidine) (R = Me (4a), (i)Pr (4b)) were prepared in high yield from Tl[RMeNN] and [CuBr(2,4-lutidine)(2)](2). Both 4a and 4b reversibly dissociate lutidine base in toluene to give [RMeNN]Cu(toluene) solvento complexes. A related base-free dicopper species [[Me(2)NN]Cu](2) (6) bridged via eta(2)-binding of opposing N-aryl rings could be isolated by the addition of Tl[Me(2)NN] to CuBr. The lutidine precursors serve as precatalysts for the aziridination of alkenes with PhI=NTs. Styrene, beta-methylstyrene, and cyclooctene gave the highest yields (59-96%) with a low olefin to PhI=NTs ratio (3:1) and 5 mol % catalyst loading. 相似文献
120.