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。
Elastic properties of holmium vanadate, HoVO 4 , have been investigated by means of an ultrasonic method. The elastic constants C 11 , ( C 11 - C 12 )/2 and C 66 exhibited remarkable softenings possessing minimum points around 13.5 K, which are characterized by the quadrupolar responses for the singlet ground state sy…
A lattice dynamical model is constructed for the NaCl type alkali halide crystals by incorporating the covalency effects in the framework of Hardy's polarization dipole model. Three effects of covalency are taken into account: (1) the reduction of the effective charge of the long range Coulomb interaction between ions…
Measurements of tracer (self-) diffusion coefficients of H in the body-centered-cubic \ensuremath{\alpha}' phase of ${\mathrm{VH}}_{\mathrm{x}}$ are reported for hydrogen concentrations x=0.17 to 0.68 and temperatures from 435 to 620 K. Experimental results, obtained from the NMR alternating-pulsed-field-gradient spin…
The electronic structures of ${\mathrm{ZrC}}_{\mathrm{x}}$, ${\mathrm{ZrN}}_{\mathrm{x}}$, ${\mathrm{NbC}}_{\mathrm{x}}$, and ${\mathrm{NbN}}_{\mathrm{x}}$ for several concentrations x were investigated by means of the Korringa-Kohn-Rostoker coherent-potential approximation and the Korringa-Kohn-Rostoker Green's-funct…
The dynamic structure factor S(q,\ensuremath{\omega}) of electrons in Li-metal single crystals for q\ensuremath{\parallel}[100], q\ensuremath{\parallel}[110], and q\ensuremath{\parallel}[111] with 0.28 a.u. <q<1.4 a.u. was measured with 1-eV resolution by using inelastic scattering of synchrotron x radiation fro…
Three types of amorphous-titania films prepared by ion- and electron-beam techniques have been annealed thermally. An amorphous-crystalline transformation is found in each of these film types at around 350 °C. Its resulting microcrystalline structure and the exact transition temperature appear to be dictated by the ru…
Crystal–melt interfaces at the triple point have been investigated by molecular dynamics techniques. The face–centered-cubic (111), (100), and (110) orientations were simulated using a modified Lennard-Jones potential between particles. Comparisons of structural and dynamic properties are made. Profiles measured throu…
We find a systematic procedure constructing the 2D and 3D " periodic " Penrose tilings, which tend to the infinite Penrose tilings. The electronic states in the 2D Penrose tiling are studied by using this sequence. We observe that the spectral measure is singular continuous in the limit of the infinite size. Most of e…
The calculated results of the orbital susceptibility for first- to fifth-stage graphite intercalation compounds (GIC's) are presented. In this calculation a new formalism for calculating the orbital susceptibility is presented. Furthermore, in order to perform calculations in an analytical way, the effective Hamiltoni…
The emission decay curves from (${\mathrm{CH}}_{3}$${)}_{4}$${\mathrm{NMnCl}}_{3}$ [tetramethylammonium manganese chloride (TMMC)] crystals doped with small amounts of ${\mathrm{Cu}}^{2+}$ deviate dramatically from simple exponential form. Consistent with the linear chain structure of TMMC, the curves are adequately d…
Localized excitations analogous to the small Holstein polaron, to localized modes in alkali halides, and to localized excitonic states, are postulated for a set of internal vibrational modes in crystalline acetanilide. The theoretical framework in which one can describe the characteristics of the ir and Raman spectros…
The geometries and energies of small silicon clusters have been investigated in a systematic manner by means of accurate ab initio calculations. The effects of polarization functions and electron correlation have been included in these calculations. Several geometrical arrangements and electronic states have been cons…
A general framework for the theory of electron–intramolecular vibration (e–mv) interaction in charge-transfer (CT) compounds is presented, particular attention being devoted to the effect of this interaction on the optical spectra of quasi-one-dimensional organic semiconductors. The common physical basis of different…
We present the first direct calculation by simulation of the excess surface free energy of a crystal–liquid interface. We perform these calculations on the (111), (100), and (110) interfaces of a truncated Lennard-Jones face-centered-cubic crystal–liquid system at the triple point by the molecular dynamics technique.…
To utilize the excellent properties of silica (SiO2) glass for a glass laser host, neodymium-aluminum (Nd–Al) and neodymium-phosphorous (Nd–P) co-doped SiO2 glasses were studied. They were prepared by plasma-torch chemical vapor deposition (CVD). It was found that a doping level less than ten times the number of Nd fo…
Data are presented on the variation of the dielectric constant and the tribo-electric coefficient for a series of pigmented, melt mixed, polymer materials. Dielectric spectra are also presented for other pigmented polymeric materials. On the basis of these data it is shown that in certain situations a correlation may…
The transient hot-strip (THS) method has been used for thermal conductivity and thermal diffusivity studies of electrically conducting materials by introducing a thin electrically insulating layer between the hot strip and the metallic material under study. The insulating layer introduces a certain thermal contact res…
Caracteristique d'un lac de Finlande. Phyto-, bacteriozooplancton. Production primaire et respiration. Poissons
A decagonal quasicrystal with point group 10/mmm has been found in Al-14-at.%-Fe alloy. Zone-axis patterns of the decagonal phase appearing at the icosahedral positions are reminiscent of the appropriate icosahedral patterns. The symmetry and the angular separation of the zone axes can be obtained from the icosahedral…
A nematic liquid crystal should present an order electric polarization associated with the gradient of order parameter, in addition to the flexoelectric polarization associated with the gradient of orientation. Using thermodynamical arguments, we show that the order-electricity coefficients are of the same order as th…