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。
The behaviour of several high Miller index crystal surfaces of gold is examined by cyclic voltammetry in 0.01 mol dm–3 perchloric acid solutions. The potentials of zero charge, Eσ= 0, and their temperature coefficients, dEσ= 0/dT for the stepped faces (332), (771), (320) and (410) are determined from a single minimum…
A generally applicable stoichiometric and kinetic model was developed for the polyesterification of unsaturated dicarboxylic acid with diols in the presence of a homogeneous acid catalyst. The model also incorporates, besides the esterification, the cis−trans isomerization and the double-bond saturation reactions. Rat…
Abstract High‐speed photography has been used visually to study the shape, surface, turbulence and behaviour of an underwater oscillating bubble generated by an airgun. The source was a BOLT airgun with a chamber volume of 1.6cu.in., placed in a 0.85m 3 tank at 0.5m depth. Near‐field signatures were also recorded in o…
Porous silicons (PSs) were prepared from a lightly doped (boron; 7 × 10 14 /cm 3 ) crystal silicon (c-Si) wafer by anodization in an aqueous hydrofluoric acid (HF) solution of different concentrations (25−55%). The porosity of these PSs was examined by nitrogen adsorption at 77 K. The relationship between the pore str…
Reactions between model compounds were carried out at high temperatures (150−250 °C) in order to provide a correct simulation of the behavior of hydroxyl and carboxyl polyester chain ends in the presence of triphenyl phosphite (TPP). The reaction between TPP and alcohol (3-phenyl-1-propanol) leads to phenoxy/alkoxy su…
We describe experiments on the spreading of liquid droplets deposited on a (wettable) liquid substrate, when the friction in the droplet dominates. We find that the horizontal radius R increases with the spreading time t like t 0.26 ± 0.02 in the capillary regime ( R < κ - 1, the interfacial capillary length), and lik…
Abstract L‐Isoleucine and the isomorphic amino acids L‐leucine and L‐valine serve as a model system in the examination of the effects of impurities on the purity and morphology of crystals recovered from batch crystallizations. Factors are determined that influence crystal purity and, concomitantly, crystal size and s…
Oxide axial profiles for Zircaloy-4 cladding measured for 17 fuel rods irradiated from 50 to 60 GWD/t in three different pressurized water reactors (PWRs) were studied. Computer simulation of the magnitude and shape of the various profiles involved five contributing interrelated effects: (1) thermal feedback, (2) radi…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTIntramolecular Condensation Reactions of α,ω-Bis(triethoxysilyl)alkanes. Formation of Cyclic DisilsesquioxanesDouglas A. Loy, Joseph P. Carpenter, Sharon A. Myers, Roger A. Assink, James H. Small, John Greaves, and Kenneth J. SheaView Author Information Properties of O…
L'emploi de derives amphiphiles des polyethylene glycols pour la preparation de vecteurs pharmaceutiques colloidaux est etudie. Les micelles preparees a partir de polymeres synthetiques amphiphiles peuvent etre utilisees pour une solubilisation et une stabilisation efficaces de produits amphiphiles therapeutiques ou d…
Low-temperature (400–800 °C) stabilisation of tetragonal zirconia, prepared by a hydroxide gel route and a metal oxalate method, both followed by low-temperature annealing, has been achieved by partial substitution of Zr4+ with Sb3+. XRD and Raman spectroscopy have been used for characterisation of the doped zirconia…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTBiomimetic Chemistry of Chromium. Intramolecular Conversion of Hydroperoxochromium(III) to Oxochromium(V)Andreja Bakac and Wei-Dong WangView Author Information Ames Laboratory, Iowa State University Ames, Iowa 50011 Cite this: J. Am. Chem. Soc. 1996, 118, 42, 10325–103…
In this work, bulk Mg2Si has been processed using the PM route. The Mg2Si powders were synthesized by the mechanical alloying technique and were characterized microstructurally and thermally. The mechanical alloying was attained at room temperature by the use of a high ball-to-powder ratio of 33:1. An X-ray diffractio…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTSix-Center Concerted Mechanism for Poly(vinyl chloride) Dehydrochlorination. Requiescat in Pace?William H. Starnes,, Joshua A. Wallach, and Hongyang YaoView Author Information Department of Chemistry and Department of Applied Scienc…
The ac conductivity and dielectric behaviors of sodium borovanadate glasses have been studied over wide ranges of composition and frequency. The dc activation energies calculated from the complex impedance plots decrease linearly with the Na 2 O concentration, indicating that ionic conductivity dominates in these glas…
Abstract Palm‐oil‐in‐water emulsions were prepared with mixtures of Tween 40 and Span 40 in various proportions. Stability and droplet‐size distribution of the emulsions were monitored. Interfacial tensions of the palm oil/water interface were also determined in the presence of these emulsifier mixtures. Emulsifying e…
Model liquid crystalline ionomers have been synthesized that consist of low molecular weight linear chains selectively end-capped at one or both end(s) with an ionic mesogenic group. ω- and α,ω-carboxylato and sulfonato polystyrene chains have been prepared by living anionic polymerization and associated with mesogeni…
The low-temperature mechanical relaxations in poly(oxy-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylene [poly(aryl ether ether ketone, PEEK], poly(thio-1,4-phenylene) [poly(phenylene sulfide), PPS], and poly(oxy-1,4-phenylenesulfonyl-1,4-phenylene), [poly(aryl ether sulfone), PES] are investigated. All three polym…
The oxide growth rate of zirconium alloys, e.g., Zircaloy-2 and Zircaloy-4, has been proposed to be controlled mainly by the transformation of the zirconium oxide from tetragonal to monoclinic structure at some distance from the metal-oxide interface, leading to cracking. This oxide growth rate model is inconsistent w…
Fine powders in CeO2-ZrO2 system have been prepared from the precipitate mixtures of cerium (III) nitrate solution, zirconium oxychloride solution and an excess amount of ammonia under hydrothermal conditions at 180°C, and their changes in crystal phase and surface area by calcination, sinterability, the crystal phase…