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。
Abstract The effects of ozone and chlorine dioxide on the structure of hardwood cellulose fibers were studied by chemical methods. Chlorine dioxide had very little effect on the cellulose degree of polymerization (DP v ), although 40–50% of the chlorine dioxide charged was consumed. By contrast, ozonation of the cellu…
Abstract The dielectric properties of (Na 0.5 Bi 0.5 ) x Sr 1− x TiO 3 (0 ≤ x ≤ 0.2) ceramic materials were studied from 10 to 300 K between 100 Hz and 1 MHz. At low substitution rates (0 ≤ x ≤ 0.02), two thermally activated relaxation modes were observed and attributed to non interacting dipoles. For x > 0.02, the…
The reaction of gallium trichloride and methanol under atmospheric pressure chemical vapor deposition conditions leads to the production of gallium oxide thin films on a variety of substrates. Scanning electron microscopy (SEM) indicated that an island growth mechanism predominated. X-ray photoelectron spectroscopy (X…
Effects of chain-end structure and residual metal compounds on thermal degradation of poly(epsilon-caprolactone) (PCL) were investigated by means of thermogravimetric and pyrolysis-gas chromatograph mass spectrometric analyses. Four types of PCL samples with different chain-end structures (alpha-carboxylic acid-omega-…
An efficient method has been developed to degrade toxic and nonbiodegradable organic pollutants such as Sulforhodamine B (SRB) and 2,4-dichlorophenol (DCP). It is based on the photocatalytic power of iron tetrasulfophenylporphyrin supported on a commercial anionic ion-exchange resin (Amberlite IRA 900) (FePR) to activ…
Blends of poly(L-lactic acid) (PLLA) with two kinds of poly[(R)-3-hydroxybutyrate] (PHB) having different molecular weights, commercial-grade bacterial PHB (bacterial-PHB) and ultrahigh molecular weight PHB (UHMW-PHB), were prepared by the solvent-casting method and uniaxially drawn at two drawing temperatures, around…
A beltlike single-crystalline CdS nanostructure was successfully synthesized by vapor-phase transport of the desired commercial CdS powder at 850 °C. Its morphology and microstructures were determined by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The observations reve…
Low molecular weight poly( N -vinylpyrrolidone) (PVP) with a hydroxyl group at one end was successfully synthesized by free radical polymerization of N -vinyl-2-pyrrolidone (NVP). Using isopropyl alcohol as solvent and 2-mercaptoethanol as chain transfer agent, a control over molecular weight (MW) profile of PVP was o…
A complete magnetic phase diagram for exchange-coupled planar hard-soft nanocomposites has been obtained in the frame of a one-dimensional micromagnetic model describing the dependence of the properties along the growth direction. The phase diagram in terms of layer thicknesses provides information on the type of dema…
Kob and Andersen's simple lattice models for the dynamics of structural glasses are analyzed. Although the particles have only hard core interactions, the imposed constraint that they cannot move if surrounded by too many others causes slow dynamics. On Bethe lattices, a dynamical transition to a partially frozen phas…
One-dimensional aggregates of CdTe nanoparticles were prepared by an exceptionally simple method of self-assembly initiated by partial removal of the stabilizing shell. The driving force of the particle self-organization is likely to be the dipole−dipole attraction between the nanoparticle cores. The obtained nanopart…
Dendrimers constitute an increasingly important field of research in chemistry for more than 15 years. After pioneering works concerning synthesis, the interest in dendrimers is now mainly driven by their properties and applications. This Account will emphasize the properties of a special class of dendrimers, that is,…
Thermal expansion and magnetic susceptibility measurements as a function of temperature are reported for YbGaGe. Despite the fact that this material has been claimed to show zero thermal expansion over a wide temperature range, we observe thermal expansion typical of metals and Pauli paramagnetic behavior, which perha…
We present an $\it{ab}$ $\it{initio}$ calculation of the exchange coupling for Fe/Nb multilayers using the self-consistent full-potential linearized augmented-plane wave (FLAPW) method. The exchange correlation potential has been treated in the local spin density approximation (LSDA) as well as generalized gradient ap…
We analyze the surface morphology of metals after plastic deformation over a range of scales from 10 nm to 2 mm, using a combination of atomic force microscopy and scanning white-light interferometry. We demonstrate that an initially smooth surface during deformation develops self-affine roughness over almost four ord…
We present resonant ultrasound elastic constant measurements of the Eu8Ga16Ge30 and Sr8Ga16Ge30 clathrates. The elastic response of the Eu clathrate provides clear evidence for the existence of a new type of four-well tunneling states, described by two nearly degenerate four level systems (FLS). The FLS's are closely…
The possibility of producing stable oil-in-water (O/W) emulsions containing oil droplets surrounded by multiple layer interfacial membranes from food grade ingredients has been demonstrated. These emulsions were produced using a three stage process that relies on the adsorption of charged biopolymers to oppositely cha…
Using benzene sandwiched between two Au leads as a model system, we investigate from first principles the change in molecular conductance caused by different atomic structures around the metal-molecule contact. Our motivation is the variable situations that may arise in break junction experiments; our approach is a co…
We consider the shape evolution of two-dimensional islands on a crystal surface in the regime where mass transport is exclusively along the island edge. A directed mass current due to surface electromigration causes the island to migrate in the direction of the force. Stationary shapes in the presence of an anisotropi…
This paper provides an elementary introduction to the basic concepts used in describing epitaxial crystal growth in terms of the thermodynamics and kinetics of atomic steps. Selected applications to morphological instabilities of stepped surfaces are reviewed, and some open problems are outlined.