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41.
42.
Suzuki IH Kono Y Ikeda A Ouchi T Ueda K Takahashi O Higuchi I Tamenori Y Nagaoka S 《The Journal of chemical physics》2011,134(8):084312
Spectator resonant KL(23)L(23) Auger electron spectra have been measured in the Si 1s photoexcitation region of Si(CH(3))(4) using monochromatized undulator radiation combined with a hemispherical electron spectrometer. The broad peak with high intensity in a total ion yield spectrum, coming mainly from excitation of a 1s electron into the 6t(2) vacant orbital, induces a spectator Auger decay in which the excited electron remains in its excited orbital. The component on the higher energy side of this peak through 1s excitation into a Rydberg orbital produces resonant Auger decays in which the excited Rydberg electron moves into a slightly higher Rydberg orbital, or is partly shaken up to a significantly higher Rydberg orbital. These findings of Si(CH(3))(4) indicate a clear contrast to those for SiF(4), in which the 1s excitation into a Rydberg orbital induces a shake-down phenomenon as well as a shake-up one. The results of these molecules exhibit a clear splitting effect among excited orbitals which are smeared out by overlapping due to lifetime widths and due to densely populated levels in the 1s electron excitation spectrum. This is consistent with the calculation on photoexcitation within the framework of density functional theory. 相似文献
43.
The incipient structural and vibrational energy relaxation process of photolyzed carbonmonoxy myoglobin was analyzed by the perturbation ensemble molecular dynamics (PEMD) method, in which many pairs of perturbed and unperturbed MD simulations are executed for ensemble-averaging to obtain statistically significant results by canceling out thermal fluctuations. First, we have shown that the experimentally reported anisotropic expansion can be detected within a picosecond after photolysis. The good agreement between the experimental and computational results indicates that the PEMD method can predict legitimately those changes driven by perturbations even if the changes might be subtle and smaller than thermal fluctuations. Second, the structural relaxation including the ??clamshell rotation?? in E and F helices was successfully analyzed. The high time resolution analysis has clarified the incipient structural dynamics on a subpicosecond timescale: the clamshell rotation starts at His64, Val68, and His93 following both the heme doming and the dissociated CO ligand collision. Third, the vibrational energy relaxation from the heme to the globin matrix is elucidated not only temporally but also spatially. This is the first ??thorough?? report of the spacetime-resolved excess kinetic energy redistribution of photolyzed MbCO in the globin matrix with a statistically significant precision, ±1?K. The incipient anisotropic vibrational relaxation occurs clearly within a picosecond in the direction perpendicular to the heme plane by the ??through-bond?? and ??through-projectile?? pathways, and the isotropic relaxation then follows by the ??through-space?? pathway. Finally, it is concluded that the PEMD method is a powerful tool to understand the incipient relaxation process driven by the perturbation. 相似文献
44.
K. Ogura T. Hattori M. Hirata M. Asano M. Yoshida M. Tamada H. Omichi N. Nagaoka H. Kubota R. Katakai 《Radiation measurements》1995,25(1-4):159-162
Several types of copolymers of CR-39 were prepared to find its usefulness as a nuclear track detector of high sensitivity. Track responses of these copolymers were investigated by irradiating energetic ions from proton through Ar. The copolymer of CR-39 monomer with N-isopropylacrylamide (NIPAAm) shows higher sensitivity than that of pure CR-39 for low LET particles such as protons. Preliminary results are reported for the track responses of copolymers (CR-39/NIPAAm) with various contents of NIPAAm as well as the etching properties. 相似文献
45.
Hiroya Yamaguchi Yoshie Yotsukura Hirosaku Sata Yoko Watanabe Hajime Hirose Noriko Kobayashi Diane M. Bless 《Journal of voice》1993,7(3)
A voice therapy program using pushing exercises to correct glottal incompetence is described. The program utilizes various types of instrumentation to determine whether or not a given patient is likely to benefit from the treatment. The program also provides feedback of target voices. Three cases with incomplete glottal closure and subsequent vocal dysphonia characterized by an asthenic breathy quality are used to illustrate the program. Details of the program, termination criteria, and problems and precautions learned from treating 29 patients over a 3-year period are presented. 相似文献
46.
Nobuyasu Itoh Takamitsu Otake Masahiko Numata Yoshie Aoyagi Mayumi Matsuo Takashi Yarita 《Analytical sciences》2008,24(9):1129-1133
To improve the extraction of polycyclic aromatic hydrocarbons (PAHs) from sediment samples, we optimized the conditions of pressurized liquid extraction (PLE). The yields increased as the extraction temperature increased from 100 to 190 degrees C, but the effect of increasing pressure (from 15 to 20 MPa) was small. Parameters of 190 degrees C and 20 MPa, near the maximum of the equipment, gave the highest yield. Under these conditions, the yields of 17 PAHs were 1.5 - 34 times those obtained by the Japanese official method (shaking and ultrasonic extraction with acetone at room temperature). 相似文献
47.
Nobuyasu Itoh Masahiko Numata Yoshie Aoyagi Takashi Yarita 《Analytical sciences》2008,24(9):1193-1197
For the accurate quantification of polycyclic aromatic hydrocarbons (PAHs) in environmental samples by isotope-dilution mass spectrometry (IDMS) and gas chromatography-mass spectrometry (GC-MS), we used deuterium-labeled PAHs (D-PAHs) as internal standards for microg g(-1)-level certified reference materials and corresponding calibration solutions. Although pressurized liquid extraction (PLE) causes significant biases in the analytical results for ng g(-1)-level samples (2.4 - 15%), biases in the analytical results by PLE (190 degrees C, 20 MPa, 2 cycles) were small (<2.3%) and negligible for microg g(-1)-level samples when expanded uncertainty (coverage factor k = 2) was considered. 相似文献
48.
The acoustic flux injection method was applied to amorphous As2S3. The velocity and the attenuation constant for shear wave at ~ 100MHz were measured through the observation of the Brillouin scattering of the light beam from a He-Ne laser. The optical transmission around absorption edge was found to change after the injection of acoustic fluxes. It was also found that the sound velocity decreased with increasing injection time of acoustic fluxes and the amount of the change of the sound velocity reached ~ 20% after 105 injections. The changes in the optical transmission and the sound velocity tended to be erased by annealing below the glass transition temperature. These phenomena are considered to be due to structural changes caused by the injection of strong acoustic fluxes. 相似文献
49.
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