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81.
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84.
Antony D. Buss Nicholas Greeves Daniel Levin Paul Wallace Stuart Warren 《Tetrahedron letters》1984,25(3):357-360
Single isomers ( or ) of homoallylic and higher alcohols can be synthesised from ω-hydroxyalkyldiphenylphosphine oxides and aldehydes, or from alkyldiphenylphosphine oxides and lactones 相似文献
85.
Ergodic actions of compact groups on operator algebras 总被引:2,自引:0,他引:2
Antony Wassermann 《Inventiones Mathematicae》1988,93(2):309-354
Summary We prove that the only ergodic actions ofSU(2) are on Type I von Neumann algebras, using the theory developed in [8]. 相似文献
86.
Rosy Antony 《Journal of polymer science. Part A, Polymer chemistry》1993,31(13):3187-3191
Polyphosphate esters were synthesized from derivatives of cardanol phosphorodichloridateates and dihydric phenols by interfacial polycondensation using a phase transfer catalyst. The polymers were characterized by IR, 1H-, 13C-, and 31P-NMR spectroscopy, and GPC. The thermal stability and thermal degradation kinetics of the polymers were determined by thermogravimetry. The flammability of the polymers was evaluated by limiting oxygen index values. © 1993 John Wiley & Sons, Inc. 相似文献
87.
A numerical scheme is developed to predict the heat transfer and pressure drop coefficients in flow through rigid tube bundles. The scheme uses the Galerkin finite element technique. The conservation equations for laminar steady-state flow are cast in the form of streamfunction and vorticity equations. A Picard iteration method is used for the solution of the resulting system of non-linear algebraic equations. Results for the heat transfer and pressure drop coefficients are obtained for tube arrays of pitch ratios of 1·5 and 2·0. Very good agreement of the present results and experimental data obtained in the past is observed up to Reynolds numbers of 1000. It is also observed that the results of the present method show better agreement with the experimental data and that they are applicable for higher Reynolds numbers than results of other studies. 相似文献
88.
Antony N. Davies 《Fresenius' Journal of Analytical Chemistry》1989,335(8):884-886
Summary The infrared spectra quality requirements of the Spektrendatenbanken-Verbundsystem (SDVS) are reported with special reference to Expert System needs. Some of the potential benefits of the system are given. A Call for Spectra is made and the guidelines for submitting spectra to the database outlined.
Dedicated to Prof. Dr. G. Tölg on the occasion of his 60th birthday 相似文献
Infrarotspektren für ein multidisziplinäres Spektroskopie-System
Dedicated to Prof. Dr. G. Tölg on the occasion of his 60th birthday 相似文献
89.
Paul Barraclough Sevin Bilgic J. Brian Pedley Antony J. Rogers Douglas W. Young 《Tetrahedron》1979,35(1):99-103
The 1H-NMR, 13C-NMR and photoelectron spectra of a variety of 2-heterobicyclo[3.2.1]octa-3,6-dienes 6 give evidence of conjugative and homoeonjugative effects in these compounds, but there is no suggestion from the data of any special contribution from the (4n+2)π neutral bishomoaromatic system. Reaction of the dienes6 with TCNE invariably yielded the product of [2+2] addition in cases where a fully characterisable product was obtained. 相似文献
90.
Antony F. McDonagh Giovanni Agati David A. Lightner 《Monatshefte für Chemie / Chemical Monthly》1998,129(6-7):649-660
Summary. Quantum yields for Z⇄E photoisomerization of the natural bi-chromophore bilirubin IXα in ammoniacal methanol solution were found to vary with excitation
wavelength, whereas no variation (within experimental error) was observed for xanthobilirubic acid and for symmetrically substituted
bilirubins (bilirubin IIIα, bilirubin XIIIα, and mesobilirubin XIIIα) in the same solvent. The quantum yield for Z⇄E photoisomerization of xanthobilirubic acid bound to human serum albumin was also invariant with excitation wavelength. In
contrast, quantum yields for Z⇄E photoisomerization of the symmetrically-substituted bilirubins did show marked excitation wavelength dependency when they
were bound to human serum albumin. These results show that quantum yields for Z⇄E photoisomerization of bilirubins are markedly sensitive to protein binding and to the nature of pyrrole ring β-substituents.
They also demonstrate that wavelength-dependent photochemistry is characteristic of bilirubins with non-identical pyrromethenone
chromophores, as expected from exciton coupling theory, and that complexation with albumin induces wavelength-dependent photochemistry
in symmetrically substituted bilirubins.
Received January 13, 1998. Accepted January 27, 1998 相似文献