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。
Taking the pseudobinary C15-Laves phase compound Ce(Fe$_{0.96}$Al$_{0.04}$)$_2$ as a paradigm for studying a ferromagnetic(FM) to antiferromagnetic(AFM) phase transition, we present interesting thermomagnetic history effects in magnetotransport measurements across this FM-AFM transition. We argue that these distinctiv…
The reptation concept in polymer dynamics is studied for model chains with added stiffness. The main idea of a chain diffusing inside a tube can be transferred from fully flexible chains. However, the picture, which renormalizes the chain of locally stiff Kuhn segments onto a flexible chain of fewer segments fails. Th…
Using a first-principles density functional approach, we calculate the first-order Raman intensities of \ensuremath{\alpha}-quartz. The dynamical charge tensors, vibrational frequencies and eigenmodes, and polarizability tensors are obtained within a perturbational approach. We calculate Raman intensities by evaluatin…
We have grown well-aligned carbon nanotube arrays by thermal chemical vapor deposition at 800 °C on Fe nanoparticles deposited by a pulsed laser on a porous Si substrate. We also attain a selective growth of carbon nanotubes on a patterned Fe film on Si substrates in terms of pulsed laser deposition and a liftoff patt…
We have analyzed the constant loss contribution to the ac conductivity in the frequency range 10 Hz--1 MHz and temperatures down to 8 K, for two Li ionic conductors, one crystalline ( ${\mathrm{Li}}_{0.18}{\mathrm{La}}_{0.61}{\mathrm{TiO}}_{3}$) and the other glassy ( $61{\mathrm{SiO}}_{2}\ifmmode \dot{}\else \.{}\fi{…
Amorphous silicon quantum dots ( $a\ensuremath{-}\mathrm{Si}$ QDs) were grown in a silicon nitride film by plasma enhanced chemical vapor deposition. Transmission electron micrographs clearly demonstrated that $a\ensuremath{-}\mathrm{Si}$ QDs were formed in the silicon nitride. Photoluminescence and optical absorption…
We report on the magnetic properties of an oxide-diluted magnetic semiconductor (DMS), Zn0.64Mn0.36O. The temperature dependence of the magnetization shows a spin-glass behavior with the large magnitude of the Curie–Weiss temperature, corresponding to a stronger antiferromagnetic exchange coupling than other II–VI DMS…
Alternation of melting points in the series of odd- and even-numbered monoacid triacylglycerols has been known for a long time, but hitherto little experimental evidence has been available to support existing theories. In this paper the melting point alternation of β-C n C n C n -type triacylglycerols is discussed, ba…
The new pnictide oxide Sr 2 MnZn 2 As 2 O 2 is reported. The crystal structure of this compound consists of a 1:1 intergrowth of square-planar MnO 2 2 - layers and ThCr 2 Si 2 -type Zn 2 As 2 2 - layers interspersed by Sr cations. This compound has been prepared by sintering the stoichiometric ratio of SrO, Mn, Zn, an…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFormation of Unsymmetrical Polyoxotungstates via Transfer of Polyoxometalate Building Blocks. NMR Evidence Supports the Kinetic Stability of the Pentatungstate Anion, [W5O18]6-, in Aqueous SolutionNebebech Belai, Masahiro Sadakane, and Michael T. PopeView Author Inform…
Both polymer blends and diblock copolymers have been investigated with small-angle neutron scattering (SANS) in varying temperature and pressure fields. Four samples were studied: a polymer blend of near critical composition and the corresponding symmetric diblock copolymer of poly(ethylethylene) (PEE) and poly(dimeth…
In the present work, a generalization of some of the interpretations of heterogeneous catalysis to the case of oxide film electrocatalysts has been attempted, using conductive boron-doped diamond supports. The very high stability of this material allowed the study of the catalytic properties of noble-metal oxide modif…
Synthesis, structural, and spectroscopic characterization of the linear cationic complex [LCr(III)(mu-[dmg)(3)Zn(II))Cr(III)L](2+) (1) in which L = 1,4,7-trimethyl-1,4,7-triazacyclononane and dmg is the dimethylglyoximato anion are reported. The Cr...Cr distance of 1 is 7 A. SQUID magnetic susceptibility measurements…
The formation rate of porous silicon by photoelectrochemical etching of n -type silicon is measured in situ by a novel technique. The reflection of the laser beam used to drive the reaction contains circular patterns, the outer radius of which bears a linear relationship to the depth of etching. The use of the radius…
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTImproved Synthesis of Indolyl FulgidesCraig J. Thomas, Mason A. Wolak, Robert R. Birge, and Watson J. LeesView Author Information Department of Chemistry and W. M. Keck Center for Molecular Electronics, Syracuse University, Syracuse, New York 13244-4100 [email protected]Cite th…
A general equation, obtained from the classical TPD theory and statistical thermodynamics, has been designed for determining the enthalpy of adsorption, Δ H, from a series of temperature-programmed desorption (TPD) runs carried out with various sample masses, heating rates, or inert gas flow rates. This equation appli…
Five isostructural compounds, K 1.25 Pb 3.5 Bi 7.25 Se 15 ( I ), K 1.46 Sn 3.09 Bi 7.45 Se 15 ( II ), Rb 1.45 Pb 3.1 Sb 7.45 Se 15 ( III ), K 1.45 Pb 3.1 Sb 7.45 Se 15 ( IV ), and K 2.15 Pb 1.7 Sb 8.15 Se 15 ( V ) were prepared by the molten flux method as silver rodlike air-stable crystals. They all crystallize in th…
A new low band gap conducting polymer, poly(2-decylthieno[3,4- b ]thiophene-4,6-diyl) ( 5 ), predicted to have nearly equi-energetic aromatic and quinonoidal forms, was synthesized by a multistep sequence involving FeCl 3 polymerization of 2-decylthieno[3,4- b ]thiophene ( 7 ) and studied. A film of 5 showed a vis−NIR…
The photophysical properties of Rh(2)(O(2)CCH(3))(4)(L)(2) (L = CH(3)OH, THF = tetrahydrofuran, PPh(3) = triphenylphosphine, py = pyridine) were explored upon excitation with visible light. Time-resolved absorption shows that all the complexes possess a long-lived transient (3.5-5.0 micros) assigned as an electronic e…
The nonlinear dynamic response of polymer melt brushes to large amplitude oscillatory shear is studied using melt state rheology of end-tethered polymer layered−silicate nanocomposites. These model melt brushes exhibit reversible strain hardening at moderate strain amplitudes, characterized by the presence of a critic…