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。
We use diffusing-wave spectroscopy to measure the motion of droplets in concentrated emulsions subjected to a periodic shear strain. The strain gives rise to periodic echoes in the correlation function which decay with increasing strain amplitude. For a given strain amplitude, the decay of the echoes implies that a fi…
Abstract Zeolites are viewed by some as the “philosopher's stone” of modern chemistry. [1] They are more or less indispensable in oil refining and petrochemicals manufacture where they are widely applied as solid acid catalysts. More recently attention has been focused on their use in the manufacture of fine chemicals…
Striking yellow luminescence is observed upon addition of a drop of solvent to colorless crystals of [Au3(CH3NCOCH3)3] that were previously irradiated with near-visible light. The trigonal prismatic stacking of individual molecules of the triangular cluster in the solid state (shown on the right) sheds light on the p…
We report the inducement of a ferromagnetic order by photogenerated carriers in a novel III-V--based magnetic semiconductor heterostructure $p$-(In,Mn)As/GaSb grown by molecular beam epitaxy. At low temperatures $(<35\mathrm{K})$, samples preserve ferromagnetic order even after the light is switched off, whereas th…
We have investigated the magnetic relaxation of clusters of eight iron ions characterized by a spin ground state of ten and an Ising anisotropy. Below 400 mK the relaxation rate is temperature independent suggesting that tunneling of the magnetic moment across its anisotropy energy barrier occurs. Using the anisotropy…
A giant magnetocaloric effect (ΔSmag) has been discovered in the Gd5(SixGe1−x)4 pseudobinary alloys, where x⩽0.5. For the temperature range between ∼50 and ∼280 K it exceeds the reversible (with respect to alternating magnetic field) ΔSmag for any known magnetic refrigerant material at the corresponding Curie temperat…
Structural studies of La 3 Ni 2 O 6.92 with a double layered perovskite structure have been performed by the X-ray Rietveld analyses between 300 K and 650 K. The interatomic distance between Ni and the apical oxygen (on the outside of NiO 2 double layer) rapidly increases around the phase-transition temperature T B ∼5…
We measured reflectance and transmittance spectra of epitaxial ${\mathrm{BaPb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$ ${\mathrm{Bi}}_{\mathrm{x}}$${\mathrm{O}}_{3}$ (x=1.0, 0.8, and 0.6) thin films, prepared by pulsed-laser deposition. The measured spectra showed strong absorption in the frequency regions below direct…
The first-order Raman spectra of A g (1) , A g (2) + B g (2) and B g (1) modes in CaWO 4 crystal were measured in the temperature range of 77–771 K and the linewidths at these temperatures were obtained. The temperature dependence of the linewidths was analyzed using the phonon dispersion curves calculated on the basi…
Band-gap states in V-doped ${\mathrm{TiO}}_{2}$ have been studied by photoemission spectroscopy over a range of photon energies encompassing the Ti 3p and V 3p core thresholds. The states show resonant enhancement at photon energies significantly higher than found for Ti 3d states introduced into ${\mathrm{TiO}}_{2}$…
This paper reports on the p to n transition in Pb doped Se–In chalcogenide glasses. Measurements of thermoelectric power in the temperature range 300 K⩽T⩽315 K, dc conductivity in the temperature range 100⩽T⩽300 K, and optical band gap (Egopt) have been carried out for Se75In25−xPbx (x=0,5,10,15) samples. The p-n tran…
The electronic states and optical transition properties of three semiconductor wires Si, GaAs, and ZnSe are studied by the empirical pseudopotential homojunction model. The energy levels, wave functions, optical transition matrix elements, and lifetimes are obtained for wires of square cross section with width from 2…
The effects of irradiation-induced luminescence enhancement by ZnS:Mn(2+) nanoparticles in poly(vinyl butyral) films are reported. The luminescence intensity increases several times when fresh samples are irradiated by a 248-nm excimer laser. The decay time also increases with exposure time. The increase in the initia…
The mass distribution of neutral carbon clusters generated by a laser vaporization of graphite in He was safely determined by a single photon (10.5 eV) ionization technique. The resulting mass distribution was surprisingly different from those reported in previous articles. It was found that the carbon clusters genera…
The electronic structure of the doped manganites ${\mathrm{Pr}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Ca}}_{\mathrm{x}}$${\mathrm{MnO}}_{3}$ was calculated by the LSDA+U method which takes into account the local Coulomb interaction between d electrons of transition-metal ions. In contrast to the standard loca…
The binding isotherm to cellulose of cellobiose dehydrogenase (CDH) from Phanerochaete chrysosporium has been compared with that of cellobiohydrolase 1 (CBH 1) from Trichoderma reesei. CDH binds more strongly but more sparsely to cellulose than does CBH 1. In a classical Scatchard analysis, a better fit to a one-site…
The most important reactive groups in collagen are amino, amido, guanidino, and carboxyl, all of which are present in comparatively large numbers. It is possible to modify amide groups present in the collagen of achilles tendons and hide trimmings by desamidation (DAM). DAM causes progressive hydrolysis of the amide g…
Theoretical interpretation of the thermally stimulated conductivity (TSC) is suggested for the temperatures at which transport is via hopping of carriers through localized bandtail states. The description is not based on specific assumptions used in the most of the previous TSC theories, such as, e.g., neglect of the…
In our present study, the origin of the increase in resistivity of polycrystalline Mn0.47Zn0.47Fe2.06O4 with increasing oxygen partial pressure was investigated by measuring thermoelectric power and electrical resistivity, and through analysis of grain size. The ferrous ion (Fe2+) concentration of the samples was esti…
The relaxation modes and rates of a single polymer chain are studied by Monte Carlo simulations of the bond fluctuation model. On the basis of the method proposed by Takano and Miyashita [J. Phys. Soc. Jpn. 64 (1995) 3688], the approximate relaxation modes and rates are obtained by solving a generalized eigenvalue pro…