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。
We present an experimental investigation of the influence of interfacial anisotropy on the cellular growth patterns observed in directional solidification of the ${\mathrm{CBr}}_{4}\ensuremath{-}8\mathrm{}\mathrm{mol}%$ ${\mathrm{C}}_{2}{\mathrm{Cl}}_{6}$ alloy at pulling velocities less than twice the cellular-thresh…
Conductivity measurements were performed on bundles of single-walled carbon nanotubes with the aid of a scanning tunneling microscope (STM). Semimetallic current-voltage (I-V) characteristics generally indicated the bundles to be electronically similar to graphite. However, by moving the STM tip along the length of th…
Ab initio molecular orbital calculations on clusters of atoms consisting of various types of silica rings (3-, 4-, 5-, and/or 6-membered rings) that can be found in vitreous silica are performed at the Hartree-Fock (HF) level. We optimized the geometries of the clusters at the HF/6--31 G $(d)$ level; the average Si-O,…
A novel Brownian dynamics method has been developed to simulate the properties of polymer brushes under shear. Simulations of 100 chains with a chain length of 100 segments have been carried out for a range of shear rates. Compared to previous methods there is a substantial saving in computational time as the self-con…
New photolabile protecting groups have been found in the 2-(2-nitrophenyl)ethoxycarbonyl and the 2-(2-nitrophenyl)ethylsulfonyl group, respectively. The influence of substituents at the phenyl ring as well as the side-chain has been investigated regarding the photolysis rates on irradiation at 365 mn. β-Branching in t…
Abstract To explain the crystallization behaviour and phase relationships of precursor derived Si‐B‐C‐N ceramics, In ( p N 2 )‐ T diagrams were calculated. The results can be used to optimize the chemical composition and the physico‐chemical conditions for heat treatment. Stabilization of specific phase assemblages re…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTSynthesis of the First Expanded Carbaporphyrinoid by the “4 + 1” ApproachTimothy D. Lash and Daniel T. RichterView Author Information Department of Chemistry Illinois State University Normal, Illinois 61790-4160 Cite this: J. Am. Chem. Soc. 1998, 120, 38, 9965–9966Publ…
The miscibility and crystallization behavior of binary crystalline blends of poly(butylene terephthalate) [PBT] and polyarylate based on Bisphenol A isophthalate [PAr(I-100)] have been investigated using differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). Both polymers were able to crystal…
Differential scanning calorimetry (DSC) and X-ray diffraction analysis were performed to study the multiple melting behavior and crystal forms of neat syndiotactic polystyrene (s-PS) in comparison with its miscible blends with amorphous atactic polystyrene (a-PS) or poly(2,6-dimethyl-p-phenylene oxide) (PPO). For neat…
Grain boundaries in model ZnO-Bi2O3 and ZnO-Bi2O3-CoO varistors and a commercial multicomponent varistor have been characterized by high-resolution electron microscopy (HREM) and scanning transmission electron microscopy (STEM), in order to determine the relationship between Bi grain boundary segregation and formation…
New liquid crystals consisting of non-chiral, banana shaped molecules are investigated by the generation of the second harmonic (SHG) of an optical wave. The temperature and electric field dependence of the SH activity of the apparent thermodynamic phases of several homologues are studied and first quantitative values…
We present large-scale molecular dynamic simulations of microcrack growth in -iron based on an N -body potential model which gives a good description of defect energetics, anisotropic elasticity and phonon frequency spectra. We demonstrate dynamic overshoot of a pre-existing microcrack under impact loading. We show th…
We study a series of the perovskite manganite compounds ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ closely spaced in doping near $x=0.50$ where the ground state undergoes a doping-dependent metal-insulator transition (MIT) from a metallic to a charge-ordered state. A significant difference i…
Thick films were prepared on glass substrates coated with indium tin oxide (ITO) via electrophoretic deposition using sols that contained phenylsilsesquioxane (PhSiO 3/2 ) particles derived from phenyltriethoxysilane. The transparency of the thick PhSiO 3/2 films was significantly improved via heat treatment at temper…
Molecular dynamics (MD) simulations have been used to investigate the effects of electron-phonon coupling on defect production and clustering produced in the primary cascade state of neutron radiation damage in -Fe. A simplified physical model of electron-phonon coupling has been incorporated with the hybrid continuum…
Ultrathin films of NiO grown on Ag(100) were investigated by photoemission microscopy. To image antiferromagnetic domains, linearly polarized light from an insertion device was used. The micrographs revealed lateral changes of the spectral line shapes of the 3p photoemission spectrum which were confirmed by taking ful…
Iron(III) tetrasulfophthalocyanine (FePcS) was shown to catalyze the oxidation of polycyclic aromatic hydrocarbons by H2O2. Benzo[a]pyrene and anthracene were converted to the corresponding quinones while biphenyl-2,2′-dicarboxylic acid was the main product of phenanthrene oxidation. The mechanism of the anthracene ox…
Atomic force microscopy (AFM) has been used to visualize events arising from the formation of intervening metastable phases at the surfaces of macromolecular crystals growing from solution. Crystals investigated were of the proteins canavalin, thaumatin, lipase, xylanase, and catalase, crystals of transfer RNA, and cr…
Synchrotron-based photoemission spectroscopy (PES), low energy electron diffraction, X-ray reflectivity, and optical and atomic force microscopy were used to study the reaction of water vapor [at pressures p(H2O)≤2.0×10−5 Torr for 3 min] with UHV cleaved MgO(100) surfaces with different levels of surface defects. The…
Poly(acrylic acid) (PAA) was the focus of an investigation in the role and behavior of polyelectrolyte dispersants in aqueous‐based colloidal processing of silicon nitride. The steady‐shear flow properties of dense suspensions were examined as a function of pH, particle volume fraction, chain length, and polymer conce…