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961.
962.
Vibronic coupling, or electron-phonon coupling, of naphthalene is calculated. A method of vibronic coupling density analysis, which has been proposed for the vibronic coupling of the Jahn-Teller active modes in a Jahn-Teller molecule, is extended for totally symmetric vibrational modes of a molecule including a non-Jahn-Teller molecule. Contrary to non-totally-symmetric modes, orbital relaxation upon a charge transfer plays a crucial role in the vibronic coupling calculation for the totally symmetric modes. The method is applied for the ground state of the naphthalene anion to compare with that of the benzene anion. The relationship between the vibronic coupling density and a nuclear Fukui function is also discussed. 相似文献
963.
Jiangfeng Lu Prof. Yukihiro Yoshida Prof. Kazuyoshi Kanamori Prof. Hiroshi Kitagawa 《Angewandte Chemie (International ed. in English)》2023,62(34):e202306942
Introduction of mechanical flexibility into proton-conducting coordination polymers (CPs) is in high demand for future protonic applications such as fuel cells and hydrogen sensors. Although such mechanical properties have been primarily investigated in one-dimensional (1D) CPs, in this study, we successfully fabricated highly flexible free-standing CP membranes with a high surface-to-volume ratio, which is beneficial for enhanced performance in the aforementioned applications. We fabricated a layered CP, Cu2(NiTCPP) (H4(H2TCPP); 5,10,15,20-tetrakis(4-carboxyphenyl) porphyrin), in which a two-dimensional (2D) square grid sheet composed of tetradentate nickel porphyrins and paddlewheel-type copper dimers was connected to each other by weak van der Waals forces. The mechanical flexibility was evaluated by bending and tensile tests. The flexural and Young's moduli of the membrane were significantly higher than those of conventional Nafion membranes. Electrochemical impedance spectroscopy analysis revealed that the in-plane proton conductivity of the membrane was maintained even under applied bending stress. Because the X-ray diffraction analysis indicates that the proton-conducting pathway through the hydrogen bonding network remains intact during the bending operation, our present study provides a promising strategy for the fabrication of new and advanced 2D CPs without using substrates or additional polymers for protonic devices. 相似文献
964.
965.
966.
The paper reports results of experiments regarding toroidal shock wave focusing in a vertical shock tube as a part of a series
of converging shock wave studies. This compact vertical shock tube was designed to achieve a high degree of reproducibility
with minimum shock formation distance by adopting a diaphragmless operating system. The shock tube was manufactured in the
Institute of Fluid Science, Tohoku University. An aspheric lens shaped cylindrical test section was connected at the open
end of the shock tube to visualize the diffraction and focusing of the toroidal shock wave released from the ring shaped shock
tube opening. Pressure transducers were flush mounted on the shock tube’s test section to measure pressure histories at the
converging test section. Double exposure holographic interferometry was employed to quantitatively visualize the shock waves.
The whole sequence of toroidal shock wave diffraction, focusing, and its reflection from the symmetrical axis were successfully
studied. The transition of reflected shock waves was observed. 相似文献
967.
Yoichi Katsumoto Kazuya Tatsumi Tatsuki Doi Kazuyoshi Nakabe 《International Journal of Heat and Fluid Flow》2010,31(6):985-995
A sensor that can efficiently and sequentially measure the deformability of individual red blood cell (RBC) flowing along a microchannel is described. Counter-electrode-type microsensors are attached to the channel bottom wall, and as RBCs pass between the electrodes, the time series of the electric resistance is measured. An RBC is deformed by the high shear flow to a degree dependent upon its elastic modulus. Hence, the profile of the resistance, which is unique to the shape of the RBC, can be analyzed to obtain the deformability of each cell. First, theoretical and experimental analyses were conducted to identify the specific AC frequency at which the effect of the electric double layer formed on the electrode surface is minimized. Measurements were then conducted upon samples of normal human RBCs and glutaraldehyde-treated (rigidified) RBCs to evaluate the feasibility of the present method. In addition, simultaneous visualization of RBC deformation was performed using a high-speed camera. Normal RBCs were observed to have a degree of deformation index (DI) of around 0.57, whereas the rigidified RBCs was DI = 0 in the microchannel. The experimental measurements showed a strong correlation between the half-width of the maximum of the resistance distribution and the DI of the RBC. 相似文献
968.
This paper describes studies of structure and dynamic behavior of combustion by use of laser-aided two-dimensional flame visualization. Attentions are given to the recent development of the laser sheet imaging techniques of velocity, temperature and concentration and its application to flame visualization. Visualization of turbulent diffusion flames by use of RIV (Rayleigh scattering Image Velocimetry) and OH-PLIF conducted by the authors are presented together with the short review of laser diagnostics of combustion. 相似文献
969.
Development of nano-scale electronic devices is a real challenge for analytical chemists. DNA is a good candidate for the construction of such nano-size assemblies. However, one has to arrange functional molecules capable of transferring electrons on DNA, which itself has no or poor electron-conducting ability. 相似文献
970.
Yoshiji Takagi 《Annals of the Institute of Statistical Mathematics》1999,51(1):99-110
Our main concern is about second order admissibility under mean squared error. A sufficient condition and a necessary condition for a modified maximum likelihood estimator to be second order admissible regardless of parametrization are obtained. In addition, some procedures for characterizing such estimators are provided. 相似文献