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。
Effective boundary conditions, in the form of two-sided impedance boundary conditions, are formulated for the linear electrodynamics of single- and multishell carbon nanotubes (CN's). The impedance is derived using the dynamic conductivity of CN's, which is obtained for different CN's (zigzag, armchair, and chiral) in…
Isobutylene (IB) polymerization kinetics at −80 °C were monitored in real time using mid-infrared ATR-FTIR spectroscopy, with diamond-composite insertion probe and light conduit technology. Monomer concentration as a function of time was obtained by monitoring the absorbance at 887 cm -1 associated with the CH 2 wag o…
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” opt…
The synthesis, characterization, and polymerization of a new cyclic ester, γ-bromo-ε-caprolactone (γBrCL), are reported. The ring-opening polymerization (ROP) of this new monomer initiated from Al(O i Pr) 3 as initiator in toluene at 0 °C was found to be living and proceeds by a coordination−insertion mechanism. Rando…
The effect of damping of spinwaves in a two-dimensional classical ferromagnetic XY model is considered. The damping rate $Γ_{q}$ is calculated using the leading diagrams due to the quartic-order deviations from the harmonic spin Hamiltonian. The resulting four-dimensional integrals are evaluated by extending the techn…
The cationic, neutral, and anionic charge states of the B 13 cluster are examined through the use of density functional theory. Several different isomers are studied and compared with a special emphasis given to the electronic structure of the lowest lying isomers. Included among the isomers are three which have been…
Hall crosses were used to measure the magnetic properties of arrays of ferromagnetic, nanometer-scale iron particles. The arrays typically consist of several hundred particles of 9 -- 20 nm in diameter. It is shown that the sensitivity of the measurements can be improved by matching the areas of the Hall cross and the…
A glass surface may still flow below the bulk glass transition temperature, where the underlying bulk is frozen. Assuming the existence at T=T* of a bulk thermodynamical glass transition, we show that the glass-vapor interface is generally wetted by a liquid layer of thickness ~ -ln(T*-T) when T--> T*. Contrary to sta…
In-plane magnetic field is found to change drastically the photoluminescence spectra and kinetics of interwell excitons in GaAs/AlGaAs coupled quantum wells. The effect is due to the in-plane magnetic field induced displacement of the interwell exciton dispersion in a momentum space, which results in the transition fr…
We propose a new model to implement organic exciton-semiconductor exciton hybridization by embedding a semiconductor quantum dot array into an organic medium. A Wannier-Mott transfer exciton is formed when the exciton in each semiconductor dot interacts via the multipole-multipole coupling with other excitons in the d…
This study concerns a molecular dynamics (MD) simulation, using the embedded-atom method (EAM), of the self-diffusion of an interstitial in the bcc metal tungsten (W) at 2000 K. It is found that the interstitial moves only along 111 diagonals and that the switches to other non-parallel directions take place through a…
We introduce a schematic nonlinear diffusion model where density fluctuations induce a rich out-of-equilibrium dynamics. The properties of the model are studied by numerical simulations and analytically in a mean field approximation. At low temperatures and high densities we find a long off-equilibrium glassy region,…
The effect of concentration of antioxidants on the Mooney scorch time of two grades of epoxidized natural rubbers (ENR 25 and ENR 50) and one grade of natural rubber (SMR L) was studied using a Monsanto automatic Mooney viscometer (MV 2000). Three types of antioxidants, viz., 2,2′-methylene-bis(4-methyl, 6-tertbutylph…
Thermal conductivity of a single-crystal lead magnesium niobate titanate-(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 with x=0.34 has been studied at temperatures from 20 to 320 K and in an applied electric field. The thermal conductivity of the crystal is similar to that of a typical amorphous solid both in the temperature dependen…
The effect of chain extender structure on properties and morphology of α,ω-bis(6-hydroxyethoxypropyl) polydimethylsiloxane (PDMS) and poly(hexamethylene oxide) (PHMO) mixed macrodiol-based aliphatic polyurethane elastomers was investigated using tensile testing, differential scanning calorimetry (DSC), and dynamic mec…
Nonextractable styrene-acrylonitrile copolymer-montmollironite (SAN- MMT) nanocomposites were prepared by two different intercalation process: (1) a usual one-step emulsion copolymerization in the presence of the Na 1 -MMT; and (2) a solution copolymerization with MMT modified by dimethyl dihydrogenated tallow ammoniu…
We report calculations of the transport properties of multiwalled carbon nanotubes based on a scattering-theoretic approach that takes into account scattering within each tube, between tubes, and at the metal contacts. We find that only the outer tube contributes to the conductance, as has been implied by experiments.…
Pharmaceutical products consist of a great range of meticulously produced formulations intended for human and veterinary use. From consumer-oriented, over-the-counter products to life-supportive pr...
Dynamically vulcanized poly(vinyl chloride)–epoxidized natural-rubber thermoplastic elastomers (PVC–ENR TPEs) were prepared using a semi-EV vulcanization system. The compounds were melt-mixed, and the rheological behavior was evaluated. The effect of curatives concentration on the rheological behavior using the shear…
To fabricate a platelet-compatible polymer, phosphorylcholine (PCe) was introduced onto the surface of polyethylene (PE) using a novel synthetic process. Acrylic acid was graft-copolymerized on the surface of PE by UV irradiation, using both the peroxide preirradiation and the simultaneous methods. Benzophenone and Mi…