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71.
Amos Altshuler 《Israel Journal of Mathematics》1970,8(1):57-64
LetC be a polygonization of a 2-dimensional closed manifold without boundary, andL(C) the set of all the faces ofC, partially ordered by inclusion, with adjoinment of a minimal and a maximal element. ThenL(C) is a lattice, and its characterization is given here. Also a characterization of the lattice of the faces of a convex 3-polytope
is given.
This is a part of the author’s Ph.D. dissertation, written under the supervision of Professor H. Furstenberg, and submitted
to the Hebrew University in June, 1969. 相似文献
72.
The technique of thin-layer chromatography, as practised in the organic industrial laboratory, is described and its applications to the analysis of petroleum hydrocarbons, fuels, lubricants, polymers, plastics and their additives, non-ionic surfactants and explosives are reviewed. The role of thin-layer chromatography in the conservation of the environment is also considered. 相似文献
73.
74.
S. F. Collins G. G. Shute B. M. Spicer V. C. Officer I. Morrison K. A. Amos 《Nuclear Physics A》1982,380(3):445-464
A relativistic mean field approach is used to determine and compare the single-particle Dirac potentials for nuclei and hypernuclei (Λ, Σ, Ξ). A simple model is used and the Dirac-Hartree-Fock equations are reduced to a Schrödinger-like equation. The subsequent central and spin-orbit shell-model potentials are compared to those of phenomenological approach and other recent microscopic approaches. In the case of hypernuclei the Hartree approximation works already quite well without any need of taking into account the strangeness exchange part coming from strange mesons. The influence of the anomalous magnetic moment of the baryon on the spin-orbit term is found to be rather important for both Λ- and Σ-hyperons. 相似文献
75.
Roger D. Amos 《Chemical physics letters》1980,70(3):613-617
The components of the dipole polarizability and of the dipole-quadrupole polarizability A of the carbon monoxide molecule have been calculated as a function of the internuclear distance using both SCF and CI wavefunctions. The resulting values of , A and then derivatives should be the most accurate ab initio estimates available for these quantities. A comparison of the SCF and CI results shows significant differences in the values obtained. 相似文献
76.
The total synthesis of (±)-desepoxy-4,5-didehydromethylenomycin A employing a retrolactonization strategy has been achieved. 相似文献
77.
Differential cross sections and analyzing powers from the inelastic scattering of 65 MeV protons leading to the 1+T=0 (12.71 MeV) and 1+T = 1 (15.11 MeV) states in 12C have been analysed as tests of a model two-nucleon t-matrix. 相似文献
78.
Bowers J Amos KE Bruce DW Webster JR 《Langmuir : the ACS journal of surfaces and colloids》2005,21(4):1346-1353
The surface behavior of a range of surfactant [Ru(bipy)(2)(p,p'-dialkyl-2,2'-bipy)]Cl(2) complexes, which we express as Ru(q)(p)C(n) where n is the alkyl chain length, p refers to the substitution position on the bipyridine ligand (=4 or 5), and q (=1 or 2) is the number of substituted alkyl chains, has been examined using neutron reflectometry. The adsorption of the single-chain Ru(1)(4)C(19) and Ru(1)(5)C(19) surfactants is strongly time-dependent, taking in excess of 10 h to form an equilibrium film. It is suggested that the slow adsorption rate is related to the alkyl chain length rather than the low monomer concentration present in the solutions. At concentrations below the critical micelle concentration (cmc) of Ru(1)(4)C(19), the film of Ru(1)(5)C(19) is denser than that of Ru(1)(4)C(19) at comparable concentration, consistent with the mass densities of the bulk solids, whereas at concentrations close to and greater than this cmc the converse pertains. Close to the cmc, the adsorbed films possess an average area per molecule significantly less than the nominal headgroup area of the surfactants (approximately 30 angstroms(2) compared with approximately 100 angstroms(2)). This fact together with consideration of the thickness and density of the adsorbed films leads to the conjecture that surface aggregates may be the adsorbing units. The adsorption of the double-chain surfactant Ru(1)(p)C(19), in contrast to the behavior of the Ru(1)(p)C(19) surfactants, is weak and independent of time. This behavior is attributed to the alkyl chain orientation. The adsorption behavior of a racemic mixture of the Delta and Lambda isomers of Ru(2)(4)C(19) has been compared with that of the Delta isomer. It is found that the film of racemic material is more closely packed than that of the resolved complex. 相似文献
79.
A set of ten differential cross sections between 10 and 40 MeV for this charge exchange reaction have been analysed. In the analyses, amplitudes associated with the virtual excitation of the giant dipole and quadrupole reasonances in28Si complement those associated with the direct reaction mechanism. Such resonance effects are essential to explain the rapid energy variation of the data. 相似文献
80.