Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Persistent spectral hole-burning phenomenon in CuBr quantum dots embedded in glass was observed. The spectral hole and the sideband holes were made together with the redshift of the absorption spectrum in proportion to the logarithm of the laser fluence and were preserved for more than 8 h at 2 K. They were erasable b…
Abstract The determination of viscoelastic property variation in short fiber‐reinforced composites, as a function of strain, temperature, and frequency, constitutes a useful tool when the existence or the strength of matrix–fiber interfaces are to be examined. In this work, these properties are studied in thermoplasti…
The complex conductivity spectra of the quasi-one-dimensional compounds ${\mathrm{K}}_{0.3}$${\mathrm{MoO}}_{3}$ (blue bronze) and (${\mathrm{TaSe}}_{4}$${)}_{2}$I in the conducting phase (above ${\mathit{T}}_{3\mathrm{D}}$=183 K and 263 K, respectively, but below the mean-field temperature ${\mathit{T}}^{\mathrm{MF}}…
Abstract Aromatic polyimides derived from 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3′‐ or 4,4′‐diaminodiphenylsulfone ( m ‐DDS or p ‐DDS) have been synthesized with a chemical imidization. The disappearance of amic acid groups and the appearance of imide groups are determined by IR and…
Biosynthesis of subtilisin is dependent on a 77 amino acid, N-terminal prodomain, which is autocatalytically processed to create the mature form of the enzyme [Ikemura, H., Takagi, H., & Inouye, M. (1987) J. Biol. Chem. 262, 7859-7864]. In order to better understand the role of the prodomain in subtilisin folding, we…
Using the Kondo lattice model with classical spins in infinite dimension, magnetic phase transition in the perovskite-type $3d$ transition-metal oxide (La,Sr)MnO$_3$ is theoretically studied. On the Bethe lattice, the self-consistency equations are solved exactly. Curie temperatures at the region of double-exchange fe…
Electron spin resonance and photoluminescence experiments have been performed on freshly etched and oxidized porous silicon. Results indicate the presence of oxygen-related centers (nonbridging oxygen-hole center clusters), which consist of similar core structures in as-made and oxidized porous silicon (PSi) samples.…
Optical absorption spectra corresponding to the 2 F 7/2 → 2 F 5/2 transition of Yb 3+ in YbCrO 3 were investigated under high magnetic fields. The energy positions of these spectra remarkably changed at the metamagnetic transition where the weak ferromagnetic moment of the Cr 3+ spins reverses its direction. From the…
We report the observation of a resonance in the infrared-absorption spectrum of heavily boron-, aluminium-, and gallium-doped silicon at room temperature. This resonance occurs near the frequency of the zone-center optical phonon (517 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$) and is attributed to a discrete-continuu…
Sodium triaqua[(1,2-ethanediyldinitrilo-κ 2 N,N')tetraacetato-κ 4 O 1 ,O 2 ,O 3 ,O 4 ]lanthanate(III) pentahydrate, Na[La(C 10 H 12 N 2 O 8 )(H 2 O) 3 ].5H 2 O, sodium triaqua[(1,2-ethanediyldinitrilo-κ 2 N,N')tetraacetato-κ 4 O 1 ,O 2 ,O 3 ,O 4 ]-neodymate(III) pentahydrate, Na[Nd(C 10 H 12 N 2 O 8 )(H 2 O) 3 ].5H 2…
The physical properties of the III-V semiconducting compounds, GaP, GaAs, and GaSb, have been calculated by employing a scalar relativistic version of the first-principles full-potential self-consistent linearized-muffin-tin-orbital method. The calculated values of the lattice parameters of the compounds are reproduce…
The structures of straight 90\ifmmode^\circ\else\textdegree\fi{} glide partial dislocations in SiC are calculated using an ab initio local density functional cluster method. Si partials containing core Si atoms are found to be strongly reconstructed with a Si-Si bond of comparable length to that in bulk silicon. The C…
The interfaces between highly (001)-oriented diamond films and the silicon (001) substrates were investigated by high-resolution electron microscopy. It was found that heteroepitaxially oriented grains which exhibit a defined orientation relationship to the substrate lattice grow directly on the clean silicon surface.…
Numerical calculations of the kinetic energy of various extensions of the one-dimensional Hubbard model including dimerization and repulsion between nearest neighbors are reported. Using the sum rule that relates the kinetic energy to the integral of the optical conductivity, one can detemine which parameters are cons…
Absorbance and site-selective fluorescence studies of Eu3+:Sr5(PO4)3F (Eu:SFAP) provide a nearly complete characterization of the Eu3+ energy levels. These results are compared with calculated energies generated by lattice-sum analysis. Eu3+ is found to occupy one site predominantly, but numerous minority sites are al…
Molecular-dynamics-simulation techniques have been used to investigate the effect of temperature on the three low index surfaces of nickel oxide. The surface energies for the {100}, {110}, and Ni {111} surfaces have been calculated as a function of temperature for NiO. The surface energies for all three surfaces were…
By controlling the extent of disorder through electrochemical synthesis at reduced temperatures, conducting polypyrrole (PPy) can be obtained in the metallic regime, in the insulating regime, and in the critical regime of the disorder-induced metal-insulator (M-I) transition. We present the results of reflectance meas…
Epitaxial PbTiO3 films were prepared by metalorganic chemical-vapor deposition on MgO(001)-, SrTiO3(001)-, and LaAlO3(001)-oriented substrates. Four-circle x-ray diffraction, transmission electron microscopy, Rutherford backscattering (RBS) channeling, and optical waveguiding were performed to characterize the deposit…
The gaseous equilibria MCl+Ag=M+AgCl and M+MCl2=2 MCl, where M=Cr, Mn, Fe, Co, and Ni were studied by mass spectrometry in the region around 1500 K, and thermochemical data were derived by second and third law methods. Dissociation energies of the metal monochlorides were evaluated by reference to AgCl, leading to the…
We present data on the dielectric relaxation in the random copolymer polybutadiene. There are two distinct peaks in the imaginary part of the dielectric susceptibility, one of which is attributable to an \ensuremath{\alpha} relaxation and the other to a Johari-Goldstein \ensuremath{\beta} relaxation. The bifurcation o…