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1.
Novel mixed valence states have been obtained by the treatment of cobaltous ferrocyanides (Co+2FeII) and ferricyanides (Co+2FeIII) in an ozone flow. The CN stretching bands occur at 2085 cm–1 for Co+2FeII and at 2160 cm–1 for Co+2FeIII. After the ozonization process of Co+2FeII, an intense band approximately at 2125 cm–1 is detected. This intermediate band must correspond to a mixed valence state of the type: FeII–CN–Co2+–NC–FeIII Mössbauer spectra recorded in situ during the ozonization of Co+2FeII show the presence of two components: a doublet with isomer shift and quadrupole splitting values close to the cobalti ferricyanide and a very broad line for the mixed valence state. From the Mössbauer and infrared spectra of the aged samples of the Co+2FeII after ozonization, a relaxation process to the initial state of the samples is observed but the mixed valence state is stable. 相似文献
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van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871
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Makins NC Ent R Chapman MS Hansen J Lee K Milner RG Nelson J Arnold RG Bosted PE Keppel CE Lung A Rock SE Spengos M Szalata ZM Tao LH White JL Coulter KP Geesaman DF Holt RJ Jackson HE Papavassiliou V Potterveld DH Zeidman B Arrington J Beise EJ Belz E Filippone BW Gao H Lorenzon W Mueller B McKeown RD O'Neill TG Epstein M Margaziotis DJ Napolitano J Kinney E Anthony PL van Bibber K Dietrich FS Gearhart RA Patratos GG Kuhn SE van den Brand JF Bulten H Jones CE 《Physical review letters》1994,72(13):1986-1989
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The dynamic electrophoretic mobility of a pair of nearby spherical particles is analyzed in the case when the thickness of the electrical double layer around each particle is comparable to the particle radius. By means of an integral reciprocal relation, a formal expression is obtained for the force and torque on N spheres subject to an oscillating electric field which may be spatially varying. Upon linearizing in the surface potential, this expression is shown to depend upon a set of purely hydrodynamic problems involving N neutral spheres, the calculation of the electric field around N neutral spheres, and the equilibrium charge distribution around N charged spheres. In the case of a single particle, the known analytic formula for the dynamic mobility is recovered. For a pair of identical particles, the dynamic mobility is calculated numerically, using known solutions to the required subproblems. An analytical expression for the mobility of a pair of widely separated spheres is also obtained by a method of reflections, and this is in excellent agreement with the numerical results outside the range of double layer overlap. Copyright 2000 Academic Press. 相似文献
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Chiu-Hong Lin Michael D. Ennis Robert L. Hoffman Gillian Phillips Susanne R. Haadsma-Svensson Nabil B. Ghazal Connie G. Chidester 《Journal of heterocyclic chemistry》1994,31(1):129-139
An efficient synthesis of the potent and orally active 5-HT1A agonists, (R)-(+)- and (S)-(-)-1-formyl-6,7,8,9-tetrahydro-N,N-dipropyl-3H-benz[e]indol-8-amines 1a and 1b , is described. This synthesis was accomplished in twelve steps from commercially available 1,5,6,7-tetrahydro-4H-indol-4-one ( 5 ). The key step involved a regio-controlled Friedel-Crafts acylation of 1-(p-toluenesulfonyl)indol-4-acetyl chloride with ethylene to yield a versatile synthon, 3-(p-toluenesulfonyl)-6,7,8,9-tetrahydro-3H-benz[e]indol-8-one ( 10 ). Subsequent coupling of this ketone with chiral α-methylbenzylamine under reductive amination conditions yielded a mixture of diastereomers. These diastereomers were efficiently separated by either chromatography or fractional recrystallization of the derived hydrochloride salts. Debenzylation of the pure diastereomers was followed by alkylation and formylation to yield (R)-(+)- and (S)-(-)-enantiomers 1a and 1b with >99% purity. 相似文献
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