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。
A high quantum efficiency for a porous silicon light emitting diode (LED) is demonstrated under pulsed operation. The LED is fabricated from a p+nn+ structure by anodic/hydrofluoric etching followed by deposition of a transparent gold contact. The LED shows a rectifying behavior and emits orange-red light under forwar…
We report electrical impedance measurements of polymer light-emitting diodes employing the soluble, conjugated polymer poly[2-methoxy, 5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) as the light-emitting layer. The diode structures were metal-polymer-metal structures utilizing thin gold as the transparent, po…
Doxorubicin entrapped within conventional liposomes (200 nm in diameter; lip-Dox) has major toxic effects on liver macrophages of the rat for a considerable period of time following i.v. administration, with respect to both specific phagocytic capacity and cell numbers. At different time-points after injection of lip-…
In the vicinity of the phase-matching angle of second-order nonlinear optical crystals, the fundamental light wave experiences an intensity-dependent phase shift which is connected with the effective attenuation due to second-harmonic generation. It is demonstrated that in the limit of weak pump depletion, the Kramers…
Variations in the band structures of the two-dimensional C60-polymers are studied, when pi-conjugation conditions are changed. We investigate the rectangular and triangular polymers, in order to discuss metal-insulator transitions, using a semiempirical model with the Su-Schrieffer-Heeger type electron-phonon interact…
An efficient method has been developed for the catalytic oxidation of pollutants that are not easily degraded. The products of the hydrogen peroxide (H(2)O(2)) oxidation of 2,4,6,-trichlorophenol (TCP) catalyzed by the iron complex 2,9,16,23-tetrasulfophthalocyanine (FePcS) were observed to be chloromaleic, chlorofuma…
A metastable phase of NbN with superconducting Tc=16.4 K was reported recently by Treece and collaborators. The reported structure of the thin film sample deviates from the rocksalt (B1) NbN structure with 25% ordered vacancies on each sublattice (space group Pm3m) and a lattice constant of 4.442 Angstroms. Using full…
Abstract The application of a new macrokinetic approach to polymer crystallization is applied in this work to a new thermoplastic polyimide (New TPI) recently developed as a matrix of advanced polymer matrix composites. The slow crystallization kinetics presented by New TPI in the entire range between the glass‐transi…
Tryptophan fluorescence spectroscopy has been used to investigate the effects of sugars and coupling cations (H+, Na+, or Li+) on the conformational properties of purified melibiose permease after reconstitution in liposomes. Melibiose permease emission fluorescence is selectively enhanced by sugars, which serve as su…
Abstract Structure–property relationships of segmented block copolyetheramides based on nylon 6 and polyoxypropylene (POP) were investigated as a function of the compositions and block lengths of the hard and soft segments by using differential scanning calorimetry, dynamic mechanical analysis, FT‐IR spectroscopy, wid…
Abstract The microstructure of polyethylene (PE)/PE composites, consisting of the high‐density PE (HDPE) matrix and ultrahigh molecular‐weight PE (UHMWPE) fibers, was investigated. Single‐fiber composites were prepared and analyzed in a hot‐stage crystallization unit attached to a polarizing microscope, aiming to find…
We discuss a {\em family} of planar (two-dimensional) systems with the following phase strucure: a Fermi liquid, which goes by a second order transition (with non classical exponent even in mean-field) to an intermediate, inhomogeneous state (with nonstandard ordering momentum) , which in turn goes by a first order tr…
Low frequency Raman and inelastic neutron scattering from glass-forming aqueous lithium chloride (LiCl,4H2O; LiCl,6H2O) are compared. The measurements were carried out from the vitreous to liquid states. The scattering from anharmonic oscillations (light scattering excess), which was separated from the one from harmon…
A model of relaxors as superparaelectrics with a distribution of the local transition temperature has been investigated. The necessary model parameters are obtained from the analysis of the static polarization response of lead magnesium niobate and then employed in simulations of the frequency-dependent dielectric pro…
A method of surface treatment was found to enhance diamond chemical vapor deposition nucleation on nondiamond substrates such as Si, SiO2, and Al2O3. The nucleation density obtained by ultrasonic abrasion with diamond powder alone was found to be enhanced by a few orders of magnitude using a mixed slurry consisting of…
The bias-enhanced nucleation (BEN) technique has been applied to TiC(111) substrates and resulted in deposition of oriented diamond particles. The orientation was observed via scanning electron microscopy. A dense region of oriented particles was not observed on the samples, presumably due to the excessive twinning of…
The spatial distribution of Mg solute in polycrystalline, single-phase Al2O3 has been obtained, using a secondary ion imaging technique. Segregation of Mg to the Al2O3 grain boundaries is clearly observed—strong evidence that the principal role of MgO is to reduce the grain boundary mobility via a solute-drag mechanis…
A thermodynamic linear perturbation theory for the Gay–Berne intermolecular potential has been developed which is able to predict the occurrence of isotropic liquid-vapour coexistence as well as the stability of a nematic phase. The theory can be regarded as a generalisation to molecular fluids of the Weeks, Chandler,…
We use numerical self-consistent field (SCF) calculations to determine the interfacial behavior of AB diblocks in a blend of immiscible homopolymers, A and B. In particular, we compare the compatibilizing effect of relatively short and long AB copolymers. In the calculations, we explicitly take into account the format…
The interference of the time-invariant magnetic-dipole contribution with the time-noninvariant electric-dipole contribution to the second harmonic (SH) provides a mechanism which is sensitive to the reduction of symmetry of Cr2O3 by antiferromagnetic ordering of spins. A pronounced polarization dependence of the SH on…