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831.
Y. Taniguchi A. Irizawa K. Iizuka K. Shimai T. Nanba T. Matsumura 《Infrared Physics & Technology》2008,51(5):438-439
We performed a spectromicroscopic measurement on TmTe single crystal with fractured surface in THz to visible regions (25 meV to 2.5 eV) at 300 K and at pressures up to 6 GPa by using a diamond anvil cell (DAC) at the spectromicroscopy station (BL43IR) of SPring-8 in the THz region and also at Kobe University in the IR–visible regions. At pressures above around 1 GPa, a prominent Drude-like structure due to the appearance of the conduction electrons was resolved in the reflection spectra. From the analysis of the spectra by a simple Drude model, we found that the pressure-induced metallic state behaves as a heavy electron system. 相似文献
832.
833.
A diastereocontrolled route to conduritols A-F has been developed starting from a common chiral building block containing an oxabicyclo[3.2.1]octane framework. 相似文献
834.
p-tert-Butylcalix[4]arene 1,3-digallate, which contains a nonbonded close contact between galloyl groups, was synthesized and its structure was determined by dynamic (1)H NMR and X-ray crystallography. The electronic spectra showed that a new absorption band of the complexes appeared at a longer wavelength region upon adding Ag(+) ion. This spectral shift was explained in terms of the interaction between the facing galloyl groups of the lower rim of the calixarene framework. 相似文献
835.
M. Shibata O. Suematsu Y. Kojima K. Kawade A. Taniguchi Y. Kawase 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):171-176
An M3 transition in a doubly odd nucleus of 156Pm was identified by internal conversion electron measurement through the β-decay of 156Nd which was separated from the fission products of 235U using the on-line mass separator KUR-ISOL. The isomeric state at 150.3keV de-excites to the ground state with the M3 transition, and the spin-parity is considered to be 1-. Nilsson configurations are also discussed on the basis of the systematics. 相似文献
836.
A generalization of the Onsager-Machlup theory from equilibrium to nonequilibrium steady states and its connection with recent
fluctuation theorems are discussed for a dragged particle restricted by a harmonic potential in a heat reservoir. Using a
functional integral approach, the probability functional for a path is expressed in terms of a Lagrangian function from which
an entropy production rate and dissipation functions are introduced, and nonequilibrium thermodynamic relations like the energy
conservation law and the second law of thermodynamics are derived. Using this Lagrangian function we establish two nonequilibrium
detailed balance relations, which not only lead to a fluctuation theorem for work but also to one related to energy loss by
friction. In addition, we carried out the functional integral for heat explicitly, leading to the extended fluctuation theorem
for heat. We also present a simple argument for this extended fluctuation theorem in the long time limit.
PACS numbers: 05.70.Ln, 05.40.-a, 05.10.Gg. 相似文献
837.
838.
We studied the structural properties of an orbital-spin-coupled spinel oxide, MnV2O4, mainly by single-crystal x-ray diffraction measurement. It was found that a structural phase transition from cubic to tetragonal and ferrimagnetic ordering occur at the same temperature (Ts,TN=57 K). The structural phase transition was induced also by magnetic field above Ts. In addition, magnetic-field-induced alignment of tetragonal domains results in large magnetostriction below Ts. We also found that the structural phase transition is caused by the antiferro-type ordering of the V t2g orbitals. 相似文献
839.
Absorption spectra and fluorescence spectra are essential for use across the photosciences, yet such spectra along with the all‐important values for molar absorption coefficient (ε) and fluorescence quantum yield (Φf) often are found with great difficulty. Here, a literature survey concerning the vital class of chlorophyll compounds has led to identification of spectra for 150 members. Spectra in print form have been digitized (with baseline corrections) and assembled into a database along with literature references, solvent identity and values for ε and Φf (where available). The database encompasses photosynthetic tetrapyrroles wherein the chromophore is a porphyrin (e.g. chlorophyll c1, protochlorophyll a), chlorin (e.g. chlorophyll a, bacteriochlorophyll c) or bacteriochlorin (e.g. bacteriochlorophyll a). Altogether, the database contains 305 absorption spectra (from 19 porphyrins, 109 chlorins and 22 bacteriochlorins) and 72 fluorescence spectra (from 10 porphyrins, 30 chlorins and 4 bacteriochlorins). The spectral database should facilitate comparisons and quantitative calculations. All spectra are available in print form in the Supporting Information. The entire database in digital form is available with the PhotochemCAD program for free downloading and further use at http://www.photochemcad.com . 相似文献
840.
Taniguchi N 《The Journal of organic chemistry》2007,72(4):1241-1245
This article describes the methodology for a copper-catalyzed preparation of numerous monochalcogenides from dichalcogenides with organoboronic acids. Unsymmetrical diorgano-monosulfides, selenides, and tellurides can be synthesized by the coupling of dichalcogenides with aryl- or alkylboronic acids using a copper catalyst in air. The present reaction can take advantage of both organochalcogenide groups on dichalcogenide. 相似文献