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61.
Yoichiro Hoshina Satoru Ikegami Kyoko Fujimoto Akihiko Okuyama Tatsuhiro Harada Susan James Peter G. Griffiths Zemin Wu Michael Lilly Andrew M. Bray 《Tetrahedron letters》2005,46(52):9035-9038
2,3-Diphenylpropionic acid library for VLA-4 antagonist was synthesized on solid-phase. Comparison of the two synthetic routes via an orthogonal generation of two aromatic amino functional groups are discussed. From this work, several compounds were identified as potent VLA-4 antagonists. 相似文献
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The crystal and molecular structure of hexahydro-cis-(1-H,4a-H)-1-p-bromophenyl-1H,3H-pyrido[1,2-c][1,3]thiazine, (C14H18BrNS), has been determined from three-dimensional diffractometer data. The space group isI41/cd and the unit cell has dimensionsa = 22·906(4),b = 22·906(4),c = 10·646(2) Å withZ = 16. The structure has been refined to a residual of 0·065 using least-squares methods on 1235 independent non-zero reflexions.The molecular geometry and conformation of the bicyclic ring is discussed and compared with the related oxazine compound. 相似文献
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The elastic scattering angular distributions for 7Li + 25Mg and 7Li + 27Al were measured at over angular ranges of 8–55° c.m. and 8–64° c.m. Previously published measurements for 24, 26Mg at 89 MeV and 24Mg at 34 MeV are reanalyzed. The cross sections were analysed using a 6-parameter phenomenological Saxon-Woods potential. No discrete ambiguities were found but the usual continuous ambiguities exist. The data were also analysed with double folded real potentials generated using the M3Y effective interaction. The folded potential must be multiplied by about 0.6 to fit the data. The extent to which 7Li optical-model potentials are determined and suggestions for further work on the normalization of the folded potential are discussed. 相似文献
66.
Two newly discovered phases on the Pt(100) surface produced by the adsorption of oxygen have been investigated using Rutherford baekscattering (RBS), nuclear microanalysis (NMA), work function changes (Δφ) and LEED. One phase is associated with the oxygensaturated surface (0.63 ± 0.03 monolayers0.81 × 1015 O atoms cm?2), where a very complex LEED pattern is observed; the other is observed at an average coverage of 0.44 ± 0.05 monolayers and gives rise to a (3 × 1) LEED pattern (when observed at room temperature). For both surfaces, RBS measurements indicate large (? 0.025 nm) Pt atom displacements. Also discussed is a new method for preparing the “clean” (1 × 1)-Pt(100) surface without the need for NO adsorption/decomposition. 相似文献
67.
R.A. McCulloch N.M. Clarke R.J. Griffiths J.S. Hanspal S. Roman J.M. Barnwell 《Nuclear Physics A》1984,431(2):344-366
Distributions of cross sections and analysing powers have been measured over the range ~ 14°–100° c.m. for the reactions at 33.4 MeV incident e using a ~ 95 % enriched 30Si target. Phenomenological optical-model analyses of the elastic-scattering data have been carried out. A DWBA analysis of the inelastic-scattering data for the 2.24 MeV (2+) and 5.49 MeV (3?) states of 30Si has yielded values of the deformation β2 and β3. The j-dependence of the analysing powers for the (3He, 4He) and (3He, 2H) reactions has identified the 6.71 MeV level of 29Si as a state, and a level near 9.5 MeV in 31P as a possible state. Spectroscopic factors for ten states in 29Si and seven states in 31P have been deduced and are compared with other work. The extent to which the data defines the 3He spin-orbit potential is discussed. 相似文献
68.
The α-phase in Zr-2.5 Nb pressure tubes has been analysed after irradiation with neutrons for temperatures between 523 and 573 K. The α-phase contains Nb in supersaturated solid solution (about 0.5−1 wt% Nb) in the as-fabricated condition. Irradiation results in the formation of small discrete precipitates having diameters of about 5 nm. Energy Dispersive X-ray (EDX) analysis using a scanning transmission electron microscope (STEM) was complicated by the presence of a self-generated X-rays in the irradiated material and by the fact that the precipitates were small relative to the foil thickness (typically 100–200 nm). Techniques developed to measure segregation of impurities at interfaces were employed to show that the precipitates were Nb-rich, their formation being consistent with a decrease in Nb concentration in the matrix. 相似文献
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