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41.
Masaaki Kubota Yoshimasa Fujishiro Ryohei Ishida 《Spectrochimica Acta Part B: Atomic Spectroscopy》1981,36(7):697-710
A strict, comparative investigation of published transition probabilities for thermometric lines and an experimental study of determinations of plasma temperatures were made for improving the accuracy in temperature measurements by the well-known slope method. Four sets of FeI lines which satisfy the requirements for the thermometric lines were selected in the wavelength region of 200–400 nm. A statistical method was used to evaluate degrees of agreement among different sets of transition probabilities. In the experimental study, excitation temperatures of a stabilized arc plasma were determined from relative line-intensities recorded by photoelectric scanning spectrometry. In conclusion, two recommended combinations of lines and transition probability data are presented for the slope temperature measurement. Line pairs used in combination of selected transition probabilities suitable for the two-line method are also given. 相似文献
42.
Yonezo Maeda Yoshimasa Takashima 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):799-806
This paper reports the unusual relaxation effect in the57Fe Mössbauer spectra of -cyclodextrin(-cyclopentadienyl)(-ethylcyclopentadienyl)iron(II) clathrate. At low temperatures it consists of a simple quadrupole doublet. However, the Mössbauer spectrum collapses to a broad peak at 320 K. This behavior is interpreted in terms of a model that a ferrocene molecule in the cavity of clathrate lattices rotates as temperature is raised. The relaxation reaches a critical rate, a lifetime of the excited nuclear state. The relaxation time for the reorientation of (-cyclopentadienyl)(-ethylcyclopentadienyl)iron(II) in a cavity was 1.2×10–7 s at 320 K and a barrier to rotation of about 8.8 KJ/mol was estimated. 相似文献
43.
Alkyl phenylsulfinates (Ph-SO-OR) were prepared from thiophenol (or diphenyldisulfide) by electrolysis in acetic acid with alcohols and sodium acetate in satisfactory yields. 相似文献
44.
Daisuke Uemura Katsuhiro Ueda Yoshimasa Hirata Hideo Naoki Takashi Iwashita 《Tetrahedron letters》1981,22(29):2781-2784
The full structure of palytoxin, a potent coelenterate toxin, is reported. 相似文献
45.
Yoshimasa Murayama 《Physica A》1981,106(3):622-632
Recently the author showed that in a superconductor the existence of scatterers like non-magnetic impurities or phonons in their long wavelength limit never limits the infinite ‘Ohmic’ conductivity which could be expected in the absence of those scatterers. In this paper we discuss the relation of such an infinite conductivity with the freely acceleratable current which is described by the second London equation. Then the results of the former paper are reproduced here by virtue of the canonical transformation technique. It is also suggested that due to the infinite ‘Ohmic’ conductivity giant voltage noises would occur as the temperature approached zero, since then the conductivity is determined by the vanishing density of current carriers (Bogolons) multiplied by an infinite (effective) momentum relaxation time. 相似文献
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49.
Hideshi Nakamura Yasushi Ohizumi Junichi Kobayashi Yoshimasa Hirata 《Tetrahedron letters》1984,25(23):2475-2478
A new bromine-containing alkaloid, keramadine, has been isolated from the Okinawan sea sponge Agelas sp. as a novel antagonist of serotonergic receptors and its structure has been elucidated by n.m.r. spectrometry. 相似文献
50.
The odor-sensing system reported earlier is used to measure odors of 47 compounds. Three computerized pattern recognition techniques, the k-NN, simplex and potential function methods, are applied to the data set for the prediction of the odors of the corresponding compounds. The best prediction results (80.9%) were obtained by means of the potential function method. 相似文献