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195.
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
196.
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
197.
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
198.
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
199.
Nishioka H Kimura A Yamato T Kawatsu T Kakitani T 《The journal of physical chemistry. B》2005,109(32):15621-15635
Developing the quantum transition rate theory of Prezhdo and Rossky (J. Chem. Phys. 1997, 107, 5863), we produced a new non-Condon theory of the rate of electron transfer (ET) which happens through a protein medium with conformational fluctuation. The new theory is expressed by a convolution form of the power spectrum for the autocorrelation function of the electronic tunneling matrix element T(DA)(t) with quantum correction and the ordinary Franck-Condon factor. The new theory satisfies the detailed balance condition for the forward and backward ET rates. The ET rate formula is divided into two terms of elastic and inelastic tunneling mechanisms on the mathematical basis. The present theory is applied to the ET from Bph(-) to Q(A) in the reaction center of Rhodobacter sphaeroides. Numerical calculations of T(DA)(t) were made by a combined method of molecular dynamics simulations and quantum chemistry calculations. We showed that the normalized autocorrelation function of T(DA)(t) is almost expressed by exponential forms. The calculated energy gap law of the ET rate is nearly Marcus' parabola in most of the normal region and around the maximum region, but it does not decay substantially in the inverted region, which is called the anomalous inverted region. We also showed that the energy gap law at the high uphill energy gap in the normal region is elevated considerably from the Marcus' parabola, which is called the anomalous normal region. Those anomalous energy gap laws are due to the inelastic tunneling mechanism which works actively at the energy gap far from zero. We presented an empirical formula for easily calculating the non-Condon ET rate, which is usable by many researchers. We provided experimental evidence for the anomalous inverted region which was basically reproduced by the present theory. The present theory was extensively compared with the previous non-Condon theories. 相似文献
200.
Deisenhofer J Braak D Krug von Nidda HA Hemberger J Eremina RM Ivanshin VA Balbashov AM Jug G Loidl A Kimura T Tokura Y 《Physical review letters》2005,95(25):257202
We report on the discovery of a novel triangular phase regime in the system La1-xSrxMnO3 by means of electron spin resonance and magnetic susceptibility measurements. This phase is characterized by the coexistence of ferromagnetic entities within the globally paramagnetic phase far above the magnetic ordering temperature. The nature of this phase can be understood in terms of Griffiths singularities arising due to the presence of correlated quenched disorder in the orthorhombic phase. 相似文献