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。
Off-lattice Monte Carlo simulations in the canonical ensemble are used to study polymer-particle interactions in nanocomposite materials. Specifically, nanoscale interactions between long polymer chains (N=550) and strongly adsorbing colloidal particles of comparable size to the polymer coils are quantified and their…
Abstract In this comparative study, the effect of carbon black (CB) on the UV aging characteristics of poly(ethylene‐co‐vinyl acetate) (EVA) was investigated. EVA, containing 13% vinyl acetate (VA), and poly(ethylene‐co‐vinyl acetate)/carbon black mixture (EVA/CB), containing 13% VA and 1% CB, were aged by means of UV…
We report on a photoemission study of the electronic structure of metallic ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{VO}}_{3}$, with $x=0.4$ and 0.5, using monochromatized He I, He II, and Al $K\ensuremath{\alpha}$ radiations. He II spectra obtained using monochromatic source exhibit large intensity f…
Abstract A series of new o ‐phenylenediamine (OPD)/ o ‐phenetidine (PHT) copolymers with partly phenazine‐like structures has been successfully synthesized at three polymerization temperatures by chemically oxidative polymerization in four different polymerization media. The molecular structures and properties of the…
Semiconducting nanocrystals, or quantum dots (QDs), have emerged as a new tool in physiological imaging, combining high brilliance, photostability, broad excitation but very narrow emission spectra, and surface chemistry compatible with biomolecular conjugation. In this review, we demonstrate the power of QDs in diver…
Nanocrystalline Bi 2 O 3 has been prepared by a ball milling process. The particle size of the ball-milled Bi 2 O 3 powder has been determined by the x-ray powder diffraction method and transmission electron microscopy. The absorption spectra, in the spectral range 300–1300 nm, indicate an increase of the optical band…
The crystal structure of Escherichia coli PdxY, the protein product of the pdxY gene, has been determined to a 2.2-A resolution. PdxY is a member of the ribokinase superfamily of enzymes and has sequence homology with pyridoxal kinases that phosphorylate pyridoxal at the C-5' hydroxyl. The protein is a homodimer with…
Abstract Utilizing anionic waterborne polyurethane (WPU) as a plasticizer, for the first time, we prepared new soy protein isolate (SPI) plastics. The WPU was prepared by using the emulsion‐extending‐chain method, and mixed with soy protein in aqueous dispersion. The mixture was cast, cured, pickled and hot‐pressed to…
We report a conventional ab initio and density functional theory study of the polarizability (alpha(alphabeta)/e(2)a(0) (2)E(h) (-1)) and hyperpolarizability (gamma(alphabetagammadelta)/e(4)a(0) (4)E(h) (-3)) of the sodium dimer. A large [18s14p9d2f1g] basis set is thought to yield near-Hartree-Fock values for both pr…
Polystyrene- block -poly(methyl methacrylate) copolymers containing [4π + 4π] anthracene photodimer at the junction point between the blocks (PS-AA-PMMA) can be cleaved to the parent homopolymer blocks upon heating above 130 °C or by UV irradiation at 280 nm. PS-AA-PMMA was characterized and then used in thin films to…
We present an ab initio molecular orbital theoretical approach to the origin of nonlinear optical (NLO) properties in the $\mathrm{Te}{\mathrm{O}}_{2}$-based materials from the viewpoint of ``electron pairs'' assigned to the individual chemical bond. Localized static dipole moments, linear polarizabilities, and hyperp…
The high-resolution calorimetric study was carried out on octylcyanobiphenyl liquid crystal (LC) confined to various controlled-pore glass (CPG) matrices with silane-treated surface. The diameter of the voids cross section ranged between 23.7 and 395 nm. The results are compared to those obtained previously on CPG voi…
Experimental evidence of a self-assembly process was obtained where high-temperature ${\mathrm{O}}_{2}$ annealing $(1025\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C})$ induced a surface reorganization in $\mathrm{Ce}{\mathrm{O}}_{2}$ deposited on $R$-cut sapphire substrates. Based on observa…
A novel mesoporous solid acid catalyst named UDCaT-4 was synthesized by incorporating superacidic centers of persulfated alumina and zirconia into highly ordered and well-defined hexagonal mesoporous silica. The catalyst is well characterized, and its properties are compared with those of bulk persulfated alumina and…
We use the density functional theory and x-ray and neutron diffraction to investigate the crystal structures and reaction mechanisms of intermediate phases likely to be involved in decomposition of the potential hydrogen storage material LiAlH(4). First, we explore the decomposition mechanism of monoclinic LiAlH(4) in…
Abstract Polypropylene/layered silicate nanocomposites were prepared from base polymer (10 MFI) and octadecylamine modified montmorillonite (1.30P nanomer), melt compounded with and without compatibilizer, i.e., maleic anhydride grafted polypropylene (Epolene‐G3015). Physico‐mechanical properties of the virgin PP and…
In this work we present a systematic density functional theory study of the electronic properties of single-walled carbon nanotubes (SWNT) with diameters ranging from 3 to 5 A. In this work meta-generalized-gradient approximation, hybrid, and screened exchange hybrid functionals are utilized to compute energy band gap…
The resistance of natural fiber-filled high-density polyethylene composite specimens to ultraviolet- (UV) and moisture-induced degradation was evaluated by measuring changes to flexural properties. High-density polyethylene (HDPE) served as the polymer matrix for four formulations: two formulations without fiber fille…
The dynamics of phase separation of three-dimensional fluids containing nanospheres, which interact preferentially with one of the two fluids, is studied by means of large-scale dissipative particle dynamics simulations. We systematically investigated the effect of volume fraction, radius, and mass of the nanoparticle…
The thermal stability of gold nanoparticles (2.5−4 nm diameter) on fully stoichiometric TiO 2 (110) rutile substrates in an O 2 atmosphere and in air at up to ambient pressure, and for comparison under ultrahigh-vacuum (UHV) conditions, was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectros…