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751.
Peter J. Lambert 《Mathematical Social Sciences》1985,9(1):19-26
The question of conflict between the rankings of income distributions with the same mean by the Gini coefficient and by individualistic social welfare functions is re-examined. The negative result of Newbery (1970) is extended. However, positive results are obtainable which reverse Newbery's conclusion by admitting into the individual's utility index a measure of his position in the income distribution, or of his deprivation with respect to others' incomes. 相似文献
752.
The chemisorption of NO on clean and Na-dosed Ag(110) has been studied by LEED, Auger spectroscopy, and thermal desorption. On the clean surface, non-dissociative adsorption into the α-state occurs at 300 K with an initial sticking probability of ~0.1, and the surface is saturated at a coverage of about . Desorption occurs without decomposition, and is characterised by an enthalpy of Ed ~104 kJ mol?1 — comparable with that for NO desorption from transition metals. Surface defects do not seem to play a significant role in the chemistry of NO on clean Ag, and the presence of surface Na inhibits the adsorption of αNO. However, in the presence of both surface and subsurface Na, both the strength and the extent of NO adsorption are markedly increased and a new state (β1NO) with Ed ~121 kJ mol?1 appears. Adsorption into this state occurs with destruction of the Ag(110)-(1 × 2)Na ordered phase. Desorption of β1NO occurs with significant decomposition, N2 and N2O are observed as geseous products, and the system's behaviour towards NO resembles that of a transition metal. Incorporation of subsurface oxygen in addition to subsurface Na increases the desorption enthalpy (β2NO), maximum coverage, and surface reactivity of NO still further: only about half the adsorbed layer desorbs without decomposition. The bonding of NO to Ag is discussed, and comparisons are made with the properties of α and βNO on Pt(110). 相似文献
753.
Chorination of saturated amide-chlorides followed by hydrolysis, thiolysis, aminolysis and catalysed dehydrochlorination leads to α-chloro acrylamide derivatives in high yield. The reaction sequence is applied to lactames and can also be extended to the synthesis of α-chloro acrylthioamide and amidine. 相似文献
754.
Malcolm R. Binns Richard K. Haynes Dale E. Lambert Paul A. Schober 《Tetrahedron letters》1985,26(28):3385-3388
The enolates generated by the conjugate addition of 1-(phenylthio)-2-octenyllithium to 4--butoxycyclopent-2-en-1-one and <-crotonolactone react with methyl 7-halohept-5-ynoates in the presence of Ph3SnCl to deliver products which may be converted into prostaglandin precursors. 相似文献
755.
Rayleigh quotient inverse iteration (RQI) is examined from the standpoint of incremental vectors. By choosing such a vector orthogonal to the eigenvector iterate at the mth step, χm, a system of linear equations is derived; solving the system is shown to be equivalent to RQI. The residual norm converges to zero for Hermitian matrices, and the coefficient matrix does not in general converge to a singular matrix as it does in RQI. Furthermore, the procedure described produces successive vector iterates whose norms do not in general become large (when m→∞) as they do with RQI. 相似文献
756.
757.
Chemically induced electron spin polarization: The dependence on radical concentration and structure
Enhancement factors (Vq) from electron spin resonance spectra of the emission-absorption type have been shown to depend on radical concentration and also on radical structure. The relative Vq's of a spectrum could be satisfactorally calculated from the theory of Adrian. 相似文献
758.
Lambert Ngoka Carlito B. Lebrilla 《Journal of the American Society for Mass Spectrometry》1993,4(3):210-215
Unimolecular metastable decomposition of cucyclodextrin cations is observed in a fast-atom bombardment Fourier transform mass spectrometry instrument. Cleavage reactions occur at the glycosidic bonds to produce oligomeric fragment ions. The first-order rate constant for the decay of the protonated parent was measured and found to be (4.2 ± 1.0) × 102s?1. 相似文献
759.
The naturally occurring sugar mimetic alkaloids 1-deoxymannojirimycin (DMJ, 1) and 6-O-alpha-L-rhamnopyranosyl-DMJ (2) have each been prepared in a completely stereoselective manner from the cis-1,2-dihydrocatechol 3, itself obtained in enantiomerically pure form by microbial oxidation of chlorobenzene. 相似文献
760.