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 electrical conductivity and thermoelectric power of lead zitconate-titanate Pb(Ti0.47Zr0.53)O3 (PZT) have been studied at temperatures up to 1000°C in gaseous ambients with controlled partial pressures of both volatile components: lead oxide and oxygen. The experimental results show the small polaron conduction me…
Samples of LaMn 1‐x Cu x O 3‐y in the range 0≤x≤0.8 were prepared from freeze‐dried solutions of the nitrates. Samples with x≤0.6 were single‐phase perovskites. At higher values of x , the samples contained La 2 CuO 4 and CuO as well as the perovskite phase. Samples of LaMn 1−x ,Cu x ,O 3−y supported on ceramic monoli…
The thermal decomposition and combustion mechanisms of PVC are examined.
Nitro-compounds were reduced to amines in high yields by using palladium, platinum, or rhodium metal catalyst with formic, phosphinic, or phosphorous acid. With formic acid, nitro-compounds containing fluorine were reduced but not those containing chlorine, bromine, or iodine. With the other acids, nitro-compounds con…
A wide range of thiols have been exposed to 60Co γ-rays at 77 K both in the pure state and in dilute methanolic or aqueous glasses. Spectra assigned to RS· radicals had gz values (z is along the C–S bond) which varied with the environment, but which were all close to 2.158 in methanol. Dissociative electron capture at…
The theory of structural stability of ceramics in severe thermal environments was explored via the use of precracking. It was shown that structural stability should be possible when an array of precracks is used, but that the precracks required for this purpose are relatively large. The approach is thus limited to sys…
Description The Fourth Conference on Composite Materials: Testing and Design was held 3-4 May 1976 at Valley Forge, Pa. The American Society for Testing and Materials' Committee D30 on High Modulus Fibers and Their Composites sponsored the conference. J. G. Davis, Jr., National Aeronautics and Space Administration-Lan…
Abstract An outline is given of heterogeneous nucleation as the main starting point for crystallization of unoriented polymer melts and solutions. The influence of temperature history on nucleation is discussed. As little is known about naturally occurring nucleants, the nature of several types of artificial nucleatin…
The reaction of 5,10,15,20-tetraphenylporphinatoiron(II)[(TPP)FeII] with carbon tetrachloride in the presence of an excess of reducing agent leads to a complex having properties consistent with the carbene, :CCl2, bound to FeII; this is believed to be the first example of a carbene complex of a metalloporphyrin.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTResonance Raman spectra and excitation profiles of tris(.alpha.-diimine) complexes of iron(II)R. J. H. Clark, P. C. Turtle, D. P. Strommen, B. Streusand, J. Kincaid, and K. NakamotoCite this: Inorg. Chem. 1977, 16, 1, 84–89Publication Date (Print):January 1, 1977Publication…
Ferroelectricity has been discovered in calcium vanadate. Large, transparent crystals have been grown by Czochralski pulling. Electrical 180° domains of millimeter dimensions are observed by etching as-grown crystals. The ferroelectric Curie temperature, Tc = 1383 K, has been determined from dielectric, thermal and py…
The long term behaviour of epoxy resin subjected to high alternating electrical stress was studied using optical magnifications of up to 1500, a scanning electron microscope, and a high sensitivity discharge detector. The formation of voids in initially void-free specimens was investigated when voltages of duration be…
The preparation, properties, and n.m.r. spectra of 1 : 1 triphenylphosphine oxide adducts of [M{N(SiMe3)2}3](M = La Eu, or Lu) and dimeric peroxo-species [M2{N(SiMe3)2}4(O2)(PPh3O)2](M = La, Pr, Sm, Eu, or Lu) are described. The crystal and molecular structures of [La{N(SiMe3)2}3(PPh3O)](1) and [La2{N(SiMe3)2}4(O2)(PP…
Silicon-29 n.m.r. spectra have been obtained for a number of aqueous solutions of sodium and potassium metasilicate. The assignment of peaks to various silicate species is discussed. Linewidth and spin–lattice relaxation time measurements are reported as a function of ageing of the solutions in sealed glass tubes, and…
The corrosion and hydriding performance of zirconium-base alloys under pressurized water reactor (PWR) and boiling water reactor (BWR) conditions, as gaged by a comprehensive review of the technical literature, has been evaluated. Starting with a brief historical description of the development of zirconium for claddin…
Abstract A detailed structural characterization of three aromatic polyamide (PPT) fibers has been carried out by means of direct electron microscope observations and X‐ray and electron diffraction analysis. Data obtained by the diffraction techniques are supplemented by high‐resolution images recorded from fragmented…
Description 45 papers present vitally important data on the behavior of zirconium alloys in nuclear reactor environments.
X‐ray photoelectron spectroscopy (ESCA) has been employed to examine several elemental metal foils which were simultaneously allowed to develop natural passivation (oxidation) layers. The metals considered included representative transition metals and also several Group III and IV elements. Sputter etching was employe…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAsymmetric syntheses via enantiotopically selective horse liver alcohol dehydrogenase catalyzed oxidations of diols containing a prochiral centerAnthony J. Irwin and J. Bryan JonesCite this: J. Am. Chem. Soc. 1977, 99, 2, 556–561Publication Date (Print):January 1, 1977Public…
Differential scanning calorimetry (d.s.c.) and nuclear magnetic resonance (n.m.r.) techniques were used to study the melting of ice in porous solids.At low water contents (less than about three monolayers) no freezing or melting was observed. As the water content was increased, a single melting peak was observed as th…