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。
The dielectric behavior of ferroelectromagnetic Pb(Fe1∕2Nb1∕2)O3 ceramics obtained using the traditional ceramic method employing three different precursors was investigated by impedance spectroscopy in the temperature range of 200–300°C. This study was carried out by means of the simultaneous analysis of the complex…
Polarization-resolved hyper Rayleigh scattering experiments were performed on gold metallic nanoparticles. These results unambiguously indicate that the second harmonic generation process of a nanoparticle is of pure electric dipole origin for the smallest particles as opposed to pure electric quadrupole, and that ret…
In the present work efforts have been made to investigate the influence of ac aging on space-charge dynamics in low-density polyethylene (LDPE). LDPE films with 200 μm were aged under various electric stress levels at 50 Hz for various times at ambient temperature. Space-charge dynamics in the samples after aging were…
By using rattan palm as a biotemplate, highly porous, α-Al2O3 ceramics with uniaxially directed porosity are produced via aluminum-vapor infiltration and subsequent oxidation in air. The high-strength ceramics retain the microstructural features of the palm (see Figure), and could be used as structural supports in cat…
A study of crack patterns in laponite films of different thickness is presented. Two cracking regimes are observed. The earlier with a higher rate of desiccation and shrinking has predominantly four-fold vertices in the crack network, while the later regime has less volume shrinking and forms mainly three-fold vertice…
Our previously defined Sparkle model (Inorg. Chem. 2004, 43, 2346) has been reparameterized for Eu(III) as well as newly parameterized for Gd(III) and Tb(III). The parameterizations have been carried out in a much more extensive manner, aimed at producing a new, more accurate model called Sparkle/AM1, mainly for the v…
We report the growth of epitaxial molybdenum oxide (MoOx,2<x<2.75) films on c plane of sapphire substrate using pulsed laser deposition in oxygen environment. The structure was characterized using x-ray diffraction, high resolution transmission electron microscopy and x-ray photoelectron spectroscopy (XP…
We report on the phonon dynamics of LiYF4 obtained by direct method using first principle calculations. The agreement between experimental and calculated modes is satisfactory. An inversion between two Raman active modes is noticed compared to inelastic neutron scattering and Raman measurements. The atomic displacemen…
The ordering of Na ions in ${\mathrm{Na}}_{x}\mathrm{Co}{\mathrm{O}}_{2}$ is investigated systematically by combining detailed density functional theory (DFT) studies with model calculations. Various ground state ordering patterns are identified, and they are in excellent agreement with available experimental results.…
We have fabricated a spin-polarized tunneling device based on half metallic manganites incorporating $Ba_{2}LaNbO_{6}$ as insulating barrier. An anomalous bias dependence of tunnel magnetoresistance (TMR) has been observed, the first of its kind in a symmetric electrode tunnel junction with single insulating barrier.…
The structures of the new compound La1.2Sr2.7IrO7+d and the recently discovered La1.2Sr2.7RuO7+d have been solved using a combination of X-ray and neutron diffraction. Both compounds crystallize in the trigonal space group R-3m and contain isolated MO6 (M=Ru,Ir) octahedra, which are arranged in well-defined layers. Re…
The structural, electronic and the bonding properties of the Sn-BEA are investigated by using the periodic density functional theory. Each of the 9 different T-sites in the BEA were substituted by the Sn atom and all the 9 geometries were completely optimized using the plane wave basis set in conjunction with the ultr…
The dynamics and thermodynamics of dislocated crystals are studied within the framework of the nonlinear theory of elastic and plastic deformations.
A hole load of spheres: Nanoporous polyelectrolyte (PE) spheres are prepared through layer-by-layer deposition of oppositely charged poly(acrylic acid) and poly(allylamine hydrochloride) onto mesoporous silica spheres (with cross-linking by heating in each step), and the subsequent removal of the silica templates by h…
Abstract Nonisothermal solidifications of medical‐grade polylactides were conducted on compression molding sheets, resulting in a variety of crystalline forms and different amounts of crystallinity. Both optically pure polylactides, poly (L‐lactide) (PLLA) and poly (D‐lactide) (PDLA), were found to crystallize at a lo…
Cylindrical nanoholes reaching 500 μm in depth can be generated in Si(100) by immersing the wafer in a solution containing HF and H2O2 after loading the wafer with Ag nanoparticles. At the bottom of the holes, Ag particles are observed (see Figure). This suggests that the Ag particles bore into the wafer and that the…
We report the discovery of a family of organic compounds, substituted 1,3,5-benzenetrisamides, that depending on subtle details of their chemical structure are capable of selectively and extremely efficiently nucleating the growth of the common α-crystal modification of the major industrial polymer isotactic polypropy…
With the purpose of fabricating ceramics where ferroelectric and magnetic order coexist, ceramics of Pb(Fe1∕2Nb1∕2)O3 have been prepared using the traditional ceramic method following three different routes. The first is a direct via starting from oxide reagents and the other two use different kinds of FeNbO4 precurso…
How do crystals nucleate and grow? Why and how do crystals form such a wide variety of morphologies, from polyhedral to dendritic and spherulitic forms? These are questions that have been posed since the seventeenth century, and are still of vital importance today both for modern technology, and to understand the Eart…
Lightly crosslinked poly(4-vinylpyridine)–silica nanocomposite microgel particles are used to prepare either oil-in-water or water-in-oil “Pickering” emulsions at around pH 8–9. Rapid demulsification occurs below pH 3, since the addition of acid leads to the protonation of 4-vinylpyridine residues which, in turn, impa…