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。
Chemical transformations that occur under flooded conditions in two limestone soils from flood-prone agricultural areas of south Florida were investigated. Redox potential and pH of Krome very gravelly loam and Chekika very gravelly loam soils were monitored over a 5-week submergence period. Within 2 days of flooding,…
Abstract The effect of ultrasonic waves upon foam extrusion has been investigated by using a special die attached to an extruder. The die consists of a special ultrasonic horn, having a circular channel, that vibrates at 20 KHz. Various ultrasonic amplitudes and flow rates were employed during extrusion of a foamed po…
We present new Monte Carlo calculations of the third and fourth virial coefficients for isotropic systems of different two-dimensional hard convex bodies: ellipses, rectangles and spherocylinders for various aspect ratios, and needles. Our results differ significantly from previously published values. The accuracy of…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIntramolecular charge transfer properties of dicyanovinyl-substituted aromaticsAlan R. Katritzky, Dong Wei Zhu, and Kirk S. SchanzeCite this: J. Phys. Chem. 1991, 95, 15, 5737–5742Publication Date (Print):July 1, 1991Publication History Published online1 May 2002Published in…
Experiments show that the characteristic periodic damage pattern that results from the optical fuse can be produced by purely thermal means by heating the fiber to temperatures in the 700-1000 degrees C range in the absence of light. The nature of the damage region bubbles suggests local temperatures high enough to so…
Dissolution rates of two commercial soda—lime silicate glasses and Pyrex borosilicate glass (Corning 7740) have been measured as a function of pH. The dissolution rate was constant with time and increased with increase in pH from 4 to 9. The activation energy for dissolution was nearly constant with pH for the Pyrex b…
A new genus of naviculoid diatoms is described from subalpine tarns on Mount Giluwe (Papua New Guinea). Its relationship to other groups is discussed.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotoluminescence studies of silver-exchanged cadmium selenide crystals: modification of a chemical sensor for aniline derivatives by heterojunction formationLarry K. Leung, Norma J. Komplin, Arthur B. Ellis, and Ned TabatabaieCite this: J. Phys. Chem. 1991, 95, 15, 5918–592…
A vapor explosion is a physical event in which a hot liquid (fuel) transfers its internal energy to a colder, more volatile liquid (coolant); thus the coolant vaporizes at high pressures and expands analyses work on its surroundings. In postulated severe accidents in current fission reactors, vapor explosions are cons…
The static adhesion of living L1210 cells (in serum-containing medium) to the surface of (styrene/methylmethacrylate) copolymers differing in styrene content (from 5% to 50% of styrene units) was investigated. The examination of wettability of the copolymer surfaces showed that the contact angle of water on the hydrop…
Slow diffusion of cobalt chloride with Na2[Fe(CN)5NO]-5H2O in aqueous solution produced crystals of Co[Fe(CN)5NO]-5H2O suitable for analysis by three-dimensional, single-crystal X-ray diffractometry. This polynuclear transition metal cyanide crystallized in the cubic space group Fm3m (No. 225, O5 h), a = 10.28 I (2)Å,…
The toughness increment resulting from the stress‐induced dilatational component of the t → m transformation is calculated for a zirconia‐toughened‐alumina (ZTA) composition containing a high proportion of tetragonal zirconia precipitates and is shown to agree very well with the experimental value. The good agreement…
This review of the chemistry and electrochemistry of the Hall-Heroult process discusses the composition and constitution of the electrolyte, phenomena occurring at the anode and cathode, the chemical behaviour of the carbon cell-lining, the mechanism of the loss of Faradaic efficiency, and matters of current concern f…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLow-valent titanium porphyrin complexes. Synthesis and structural characterization of the first titanium(II) porphyrin complex, (.eta.2-diphenylacetylene)titanium octaethylporphyrinL. Keith Woo, J. Alan Hays, Robert A. Jacobson, and Catherine L. DayCite this: Organometallics…
Vapor-deposited films prepared under low adatom mobility conditions commonly exhibit columnar structures. We present the scanning electron microscopy study of Cu films with a thickness around 3.7 μm deposited on rough Al2O3 ceramic substrates and smooth SiO2 substrates. The Cu films were deposited using the partially…
Abstract Poly(phenylene-chloroethylene) film was prepared by the vapor deposition polymerization of 1,9-dichloro[2.2]paracyclophane and was converted into fully extended π-conjugated poly (phenylene-vinylene) by thermal dehydrochlorination at 300 °C under nitrogen for 1 h.
Photoinduced absorption spectra for vibrational and electronic excitations have been investigated in a prototypical one-dimensional Peierls-Hubbard system, potassium tetracyanoquinodimethane crystals. Strong photoinduced-absorption signals and their temperature-and time-dependent characteristics are discussed in terms…
We have used x-ray photoelectron spectroscopy (XPS) to measure the valence band offset in situ for CdSe/ZnTe (100) heterojunctions grown by molecular-beam epitaxy. XPS measurements were performed for films of CdSe (100) and ZnTe (100), and for heterojunctions consisting of either ∼25 Å of CdSe grown on ZnTe or ∼25 Å o…
Silica soots were sintered under a reducing ambient to study the generation mechanism of the oxygen-deficient-type defects in silica glasses. Glasses sintered under H2/He gas mixtures or vacuum were prepared with an intent to produce oxygen-deficient centers. Two optical-absorption bands were generated in the silica g…
Ten Gomphonema taxa and four taxa of Gomphoneis from the upper Laurentian Great Lakes are considered. Gomphonema taxa include five new species and one new variety and a new record for the Great Lakes. Two new Gomphoneis taxa are described. SEM study of Gomphonema species indicates that all have occluded puncta. Occlus…