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。
Abstract Alternating copolymers containing 4,4‐isopropylidene‐bisphenol (BPA) and comonomers with various degrees of polarity have been evaluated to find comonomer structures which provide low melt viscosity and good thermal stability. The materials were prepared by pyridine‐catalyzed nucleophilic displacement reactio…
Thermally stimulated discharge (TSD) of polymers has become a widely used experimental technique for the investigation of various material parameters, such as charge storage properties,1surface voltage stability,2–3determination of the mean depth of the internal charge,4activation energies5of traps and the trap struct…
Abstract The electrical resistivity of the 5,6: 11,12-bis(epidithio)naphthacene-bromine system (TTT–Brn) was examined over the composition range from n=0.3 to 2.0 using polycrystalline compactions. The room-temperature resistivity shows a minimum of about 7 Ω cm near n=0.5, suggesting the formation of a mixed-valence…
Methods of test for measuring the resistance of plastics to environmental stress cracking are critically reviewed. Particularly consideration is given to the relative merits of constant strain and constant stress tests and the most suitable procedure for the generation of design data discussed. Note is taken of the po…
Klebelsbergite is an antimony sulfate found at Felscibdnia, Hungary, and recently at Pereta, Tuscany, Italy. Crystal data are: a: 5.766(2), b: 11.274(2), c : 14.887(DA; space group Pca2r; Z: 4. The atomic positions were determined by direct methods and refined by leastsquares calculations to an R index of 0.045 for I…
An explicit equation for the glass transition temperature (Tg) of compatible polymer-diluent mixtures is derived from a comparison of classical and statistical thermodynamic relations of the excess entropy. The ratio of Tg for plasticized/unpiasticized systems is related to the ratio of configurational partition funct…
Cattle were grazed for four months on pasture irrigated by effluent from activated sludge plants, a trickling filter plant, from a lagooning process with raw sewage, and then killed and their heart, diaphragm, tongue, and muscles of their head and one forelimb were sliced and examined for Cysticercus bovis. None of th…
Measurements of the lattice parameters of 1T- and 4Hb-TaS2 have been made between 300 and 500 K. Discontinuities were observed and measured at the charge-density-wave (CDW) transition temperatures. Observations of the super-lattices in this temperature range indicate that the interactions between CDWs in adjacent laye…
Absorption due to the 1.38-μm overtone of the OH−vibration in silica has long been an obstacle to low-loss propagation in optical fibers at wavelengths near the dispersion minimum. The corresponding absorption spectrum of OD−in silica, however, has a window in this region. A deuterated fiber with OD−content comparable…
Nb2P 5 was prepared by reaction of the elements at 3-5 GPa and 1273 K using a cubic-anvil-type apparatus. The crystal is orthorhombic, Pnma, with a = 16.742 (3), b = 3.3499 (6), c = 7.912 (1) A, Z = 4, and D x = 5.10 Mg m -a. The structure was refined to R = 0.037 for 1198 independent reflections. The structure of Nb2…
Dielectric absorption studies have been made of a number of aromatic sulfides, sulfoxides, and sulfones in a polystyrene matrix at a variety of temperatures in the frequency range of 102–105 Hz, and in three cases between 104–107 Hz. One compound, bis (4-pyridyl) sulfide, was also examined as a pure compressed solid i…
Polymer crystallization is assumed to be controlled by an equilibrium distribution of intramolecular clusters (“bundles”), insofar as it consists of their aggregation to the side surface of the crystallites. The average contour length of the loops within the bundles dictates the lamellar thickness. Each bundle contain…
It has been reported that under certain conditions the polymer network of acrylamide gels immersed in acetone—water mixtures undergoes a discrete transition in equilibrium volume with changes in acetone concentration or temperature. In the present work, the physical and chemical basis of this phase transition is ident…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBehavior of nickel-copper alloy in hydrogenation, orthohydrogen-parahydrogen conversion and H2-D2 exchange reactionK. C. Khulbe, R. S. Mann, and A. ManoogianCite this: Chem. Rev. 1980, 80, 5, 417–428Publication Date (Print):October 1, 1980Publication History Published online…
Abstract Strong morphologic variations were noted in the chloromethylation of styrene copolymers incorporating TAT or DVB as crosslinking agents. In the first case control over the chloromethylation conditoins (solvent, temperature, time) can be applied in order to mold the final porous structure of the chloromethylat…
Abstract A series of C 4 ‐C 12 alkyl acrylates and methacrylates was polymerized with starch by irradiating starch–monomer mixtures with 60 Co. Homopolymers were extracted with cyclohexane. The amounts of insoluble versus soluble synthetic polymer in polymerization run with alkyl acrylates varied less with the chain l…
A theory is developed for predicting the strength of a bundle of sufficiently large number of elements, if the average breaking load and the breaking-elongation distribution of these elements are known. The usefulness of the theory is illustrated with data on cotton fibers.
The non-linear visco-elastic behavior of various thermoplastic materials has long ago been established. A vast field, however, remains unexplored, firstly, in finding out workable theories for actual engineering applications with their limits of applicability specified, and secondly, in understanding the physical mech…
The Sm-N transition temperatures of the C1-C12 homologs of some p-phenylene di-p-n-alkoxybenzoates were studied. For three homologous series of these esters (unsubstituted, methyl-substituted, and chlorosubstituted on the central phenylene ring), the transition temperature was found to decrease at first on ascending t…
Abstract The distribution of polyenes which results from the chemical dehydrochlorination of poly(vinyl chloride) has been studied in dichloromethane (DCM) and tetrahydrofuran (THF) solvents. A higher percentage of longer polyenes is formed in DCM than in THF. On the addition of trifluoroacetic acid to DCM solutions o…