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161.
162.
K. Kimura Y. Achiba M. Morishita T. Yamazaki 《Journal of Electron Spectroscopy and Related Phenomena》1979,15(1):269-274
A new method for determining absolute photoionization cross sections for gaseous compounds is proposed. In this method a mixture of a sample and a standard gas (N2) is used in photoelectron intensity measurements so that the relative intensity of the component is obtained with respect to N2 The relative photoelectron band area is converted to the absolute photoionization cross section on the basis of the absolute cross-section data of N2 recently reported by Samson et al. This method has been applied to various aliphatic compounds to study the effect of alkyl substitution on photoionization cross sections of O- and N-nonbonding electrons for 584-Å radiation. 相似文献
163.
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167.
A. Kimura H. Kobayashi M. Nishida P. Valentin 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,34(2):189-215
Average radiative transition probabilities for argon atoms have been calculated for transitions between 24 levels in two groups characterized by the atomic core terms 2P1/2 and 2P3/2 by using the method of Bates and Damgaard. The results are compared with data in the NBS tables (Wiese et al.) and with those of Katsonis and Drawin. We find satisfactory agreement for the order of magnitude, even for transitions between lower lying levels. Parameters, which appear in Drawin's semiempirical cross-section expressions for electronic excitation of optically allowed and parity-forbidden transitions, are determined with the multipole expansion method proposed by Sobel'man for transitions between the specified levels. Most of these are easily obtained, but the method must be improved for transitions between levels having the same azimuthal quantum number because the summation over the constituent terms does not converge. 相似文献
168.
Critical modes of one-dimensional fermion systems are examined by use of the renormalization group technique. Both strongly incommensurate and commensurate bands are treated. Both frequency and momentum dependence and the analytic property of the response functions are determined. It is stressed that for some region of coupling constants the model has anomalous dimensions, i.e. it has critical indices dependent on the coupling constants. The results are applied to predict the temperature dependence of the shift and relaxation of the nuclear magnetic resonances. 相似文献
169.
Makoto Kimura Kasumi Kashikura Satomi Yokoi Yumiko Koiwa Yoshikazu Tokuoka Norimichi Kawashima 《Optical Review》2005,12(3):207-210
We determined photodynamic therapy (PDT) efficacy using a flash wave (FW) and a continuous wave (CW) light, of which the fluence rate was 70 W/cm2, for murine thymic lymphoma cells (EL-4) cultivated in vitro. The irradiation frequency and the pulse width of the FW light were in the range of 1–32 Hz and less than one millisecond, respectively. 5-Aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) was used as a photosensitizer. When EL-4 with ALA administration was irradiated by the light for 4 h (irradiation fluence: 1.0J/cm2), the survival rate of EL-4 by the FW light was lower than that by the CW light, except for the FW light with irradiation frequency of 32 Hz, and decreased gradually with decreasing irradiation frequency. Moreover, the FW light, especially at lower irradiation frequency, was superior to the CW light for the generation of singlet oxygen in an aqueous PpIX solution. Therefore, thehigher PDT efficacy for EL-4 of the FW light would be caused by the greater generation of singlet oxygen in the cells. 相似文献
170.
J.?SichelschmidtEmail author V.?Voevodin V.?Pacheco Yu.?Grin F.?Steglich T.?Nishi S.?Kimura 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,46(3):363-366
We performed measurements of the optical reflectivity in the energy range 0.007–30 eV
on the clathrate-VIII type compound α-Eu8Ga16- xGe30 x in order to investigate its electronic band
structure. The very low charge carrier concentration as well as ferromagnetic ordering
of the divalent Eu ions below 10.5 K characterize the spectra at photon energies below
≃0.4 eV in accordance with the results of band structure calculations. Disorder
induced bound states have been identified to affect the optical conductivity at energies
between 10 and 100 meV. 相似文献