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881.
T. Yamazaki S. Nagamiya O. Hashimoto K. Nagamine K. Nakai K. Sugimoto K.M. Crowe 《Physics letters. [Part B]》1974,53(1):117-120
The g factors of the negative muons bound to Zn, Cd, and Pb nuclei have been determined. The observed values after the corrections for the internal fields have shown substantial deviations from the free-muon g factor: is (1.3±0.6)% for Zn, (2.2±1.4) % for Cd, and (5.0±2.2)% for Pb. These shifts are in good agreement with the relativistic binding corrections for finite-size nuclei calculated by Ford et al. 相似文献
882.
Mitsuru Ueda Masahiko Yabuuchi Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1977,15(11):2641-2651
The ring-opening polyaddition of 2,2′-disubstituted bis(3-buten-4-olides) with aliphatic diamines in m-cresol at room temperature afforded in quantitative yields polyamides with a pendant ketone moiety having inherent viscosities of up to 0.7. On the other hand, the polymerization in m-cresol at 80°C with acidic catalysts and at 160°C without any catalyst yielded directly polypyrrolones, a novel class of polyheterocycles. The cyclodehydration of the open-chain polyamides to polypyrrolones was also achieved by simply treating the polyamide films with methanolic hydrochloric acid at room temperature. Both of the polymers were generally soluble in hot polar solvents such as dimethylformamide, m-cresol, and nitrobenzene. The polypyrrolones began to lose weight gradually at around 250°C in nitrogen as determined by thermogravimetric analysis, while the thermograms in air showed an appreciable weight increase at about 230°C. 相似文献
883.
Masahiko Motegi Masahiko Moritani Hiromichi Kawai 《Journal of Polymer Science.Polymer Physics》1970,8(4):499-512
Light scattering from oriented samples of crystalline polymers is affected by the birefringence of the sample. An extension of the theory for scattering from uniaxially deformed two-dimensional and three-dimensional spherulites is made so as to include the retardation of the incident and scattered beams in passing through the birefringent sample. Strain influences scattering, in that it changes the birefringence of the sample and it also changes the anisotropy and shape of the spherulites. Scattering intensities are calculated for both crossed and parallel polarizers as a function of Ω, χ, and Φ, where Ω is the angle between the stretching direction of the sample and the horizontal direction, and χ and Φ are the angles between the stretching direction and the polarization directions of the polarizer and analyzer, respectively. It is shown that for crossed polarizers with Φ = 45° and χ = 45° birefringence changes largely influence the results but that for the polarizers parallel at Φ = 0° and χ = 0° or crossed at Φ = 90° and χ = 0° the birefringence effect is minimized. The intensity distributions for crossed polarizers at Φ = 45° and χ = 45° from polyethylene films stretched to give retardations up to several wavelengths, are found to be in good agreement with the calculated results. 相似文献
884.
Masahiro Hashimoto 《Optics Communications》1980,32(3):383-384
An asymptotic formula is presented by means of which WKB's eigenvalues of a circular waveguide can be corrected in analytic form. Maslov's formula derived in 1960 for the determination of Schrödinger's eigenvalues is given for comparison. Both results are shown to be in complete agreement in a specific case. 相似文献
885.
886.
887.
Local densities of states are calculated by use of a cluster model. Resonant states due to Cl 3p orbitals appears in the valence band. The calculated energy-splittings between non-bonding px(py) and bonding pz orbitals agree well with the observed ones. 相似文献
888.
Development of an electrochemical detector for high-performance liquid chromatographic assay of brain catecholamines 总被引:1,自引:0,他引:1
An electrochemical detector that utilizes the reduction-oxidation phenomena of electrochemically active substances has been developed for high-performance liquid chromatography. The construction and application of the detector to brain catecholamines, particularly for norepinephrine and dopamine analysis, are described. The differences between this detector and those reported previously are discussed. 相似文献
889.
890.