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。
1H NMR spectra of a series of high-spin (meso-tetraalkylporphyrinato)iron(III) chlorides, [Fe(TRP)Cl] where R = Me, Et, Pr, or (i)Pr, have been measured at various temperatures in CD(2)Cl(2) solution. In the case of the Et, Pr, and (i)Pr complexes, either the methyl or the methylene signal split into two signals with…
The effects of initial particle size on the microstructure of silicon nitride ceramics produced by pressureless sintering have been investigated. The microstructures of the silicon nitride ceramics varied considerably with the size of the initial powder. With decreasing powder size, abnormal grain growth was enhanced,…
The interfacial states in adsorbed PEO layers on silica were probed through the self-exchange of coumarin-tagged chains and native analogues. New evidence for nonequilibrium interfacial behavior is presented, though prior studies supported local equilibrium for adsorbed PEO. Results suggest that entanglements or high…
We study two-dimensional binary mixtures of parallel hard squares as well as of disks. A recent cluster algorithm allows us to establish an entropic demixing transition between a homogeneously packed fluid phase and a demixed phase of a practically close-packed aggregate of large squares surrounded by a fluid of small…
A cotton-bound serine protease inhibitor of elastase (fiber-inhibitor) has been formulated for in vitro evaluation in chronic wound fluid. As a model to understand the properties of the inhibitor in wound dressings, the kinetic profile and in vitro release of the fiber-inhibitor formulation have been examined. The ela…
Structure-property relations in meaoscopic BaTiO3 and PbTiO3 are reviewed from the stand-point of effects of crystallite size on intrinsic behavior using the Landau-Ginzburg-Devonshire formalism. Experimental results based on x-ray diffrdctometry and quantitative calorimetry indicate that the critical crystallite size…
Epitaxial LaNiO3 (LNO) thin films were grown on (001) SrTiO3 substrates by laser molecular-beam epitaxy. The growth process of the LNO films was monitored by in situ reflection high-energy electron diffraction (RHEED). Clear RHEED patterns and the intensity oscillation of RHEED were observed during the epitaxial growt…
Polarized ir spectra of oriented films of α-helical poly(l-alanine) (α-PLA) have been obtained as a function of residual solvent dichloroacetic acid (DCA). The amide A, B, II, and V regions exhibit multiple bands whose structure depends on the residual DCA content, and those associated with the αI-PLA structure have b…
The Rosenburg method has been applied to determine physicochemical properties of at 900–1000°C and oxygen pressures from 0.005 to 0.1 atm. The defect concentration was proportional to , whereas the defect diffusion coefficient was essentially independent of the ambient oxygen pressure. This is interpreted to reflect t…
The local coordination environments of alkali cations (Li + and Na + ) in single- and mixed-alkali silicate glasses have been investigated by using cluster model calculations at the Hartree−Fock/6-31G(d) level. The optimized structural parameters obtained for the model clusters are in good agreement with the observed…
Unidirectional liquid crystal (LC) alignment produced by a polarized ultraviolet-light (UV) exposure was examined using various polyimides (PIs) which consist of different tetracarboxylic dianhydrides and diamines. The photosensitivity and anchoring energy of the LC alignment as a function of UV dosage are summarized…
The laser-induced nonlinear optical response of micellar lyotropic liquid crystals in the nematic and isotropic phases is presented. The Z-scan technique is used to measure the amplitude and the sign of the nonlinear refractive indices of the lyotropic mixture. The amplitude of the nonlinear refractive indices $(\ensu…
Because of their inherent toughness and flexibility, low density, thermal stability, radiation resistance and mechanical strength, aromatic polyimides have excellent potential for use as advanced materials on large space structures. Polyimides were uniaxially and biaxially oriented to further enhance their dimensional…
The effects of nitrogen doping on the complex refractive indices of Ge 2 Sb 2 Te 5 phase-change optical recording materials and their wavelength dependence were examined. With an increase in nitrogen concentration, the extinction coefficients decreased monotonically. The calculated reflectance spectra at normal incide…
A computer simulation was performed to investigate the structure and properties of extrinsic grain-boundary (GB) defects in the {11, 〈101〉 {131} symmetric tilt boundary. An embedded-atom method potential was employed to represent aluminium. Standard molecular dynamics relaxation techniques were used to compute low-tem…
This study investigates the influence of semipermeable functional films on the sur face vapor pressure and temperature of fabric-film-fabric assemblies. The film added between two fabric layers affects vapor pressure and temperature changes on both surfaces of the assembly under simulated body-clothing conditions. The…
The Rayleigh-Plesset bubble dynamics equation coupled with the bubble motion equation developed by Johnson and Hsieh was applied to study the real flow effects on the prediction of cavitation inception in tip vortex flows. A three-dimensional steady-state tip vortex flow obtained from a Reynolds-Averaged Navier-Stokes…
Layers of oriented carbon nanotubes and nanometer-size plate-shaped graphite crystallites are obtained by chemical vapor deposition in a glow-discharge plasma. A structural-morphological investigation of a carbon material consisting of nanotubes and nanocrystallites is performed, and the field-emission properties of t…
The structure of the oxyphosphate Ni 0.50 TiO ( PO 4 ) has been determined ab initio from conventional X-ray powder diffraction data by the “heavy atom” method. The cell is monoclinic (space group P 2 1 / c , Z =4) with a =7.3830(5) Å, b =7.3226(5) Å, c =7.3444(5) Å, and β=120.233(6)°. Refinement of 46 parameters by t…
The effect of 500 eV N2+ irradiation of graphite and diamond surfaces has been investigated by in situ electron spectroscopies (Auger electron spectroscopy and x-ray photoelectron spectroscopy). The chemical state of the implanted nitrogen and carbon have been studied as a function of: (i) implantation temperature in…