Materials Literature
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Energy, temperature and electron current dependence of the contamination rate have been examined experimentally. When the density of the electron current irradiating a specimen is of the order of 10−3 A/cm2, the contamination rate is inversely proportional to (v/c)2, where v and c are the velocities of electrons and l…
Chabourneite, Tl₂₁(Sb, As)₉₁S₁₄₇ is triclinic, P1, with a = 16.346, b = 42.602, c = 8.534 Å, α = 95.86°, β = 86.91°, γ = 96.88°, Z = 1, Dx = 5.121 g.cm⁻³. The strongest lines in the powder pattern are : 4.196(5) (0.10.0 ; 2.8.0), 4.067(6) (0.[-4].2 ; [-4].2.0), 3.928(7) ([-4].4.0), 3.573(10) (2.[-6].2 ; 2.10.0), 3.485…
Abstract The volumetric behaviors of cholesteryl oleyl carbonate (COC) and cholesteryl oleate(CO) were investigated around the smectic(Sm)-cholesteric(Ch) and cholesteric-isotropic(I) transitions by using chromatographically purified materials. Both transitions showed marked pretransition phenomena in COC and CO. The…
The design and use of kinetic energy marine sediment penetrators require a capability for predicting penetration depth. A natural test target of soft saline clay deposits was chosen for its similarity to marine sediments, and 35 instrumented penetrator tests were conducted. An equation was developed to fit the data wi…
The H2–D2 kinetic isotope effect was measured on a Ru/SiO2 catalyst not only for the hydrogenation of CO but also for the hydrogenation of deposited carbon formed bv disproportionation of CO; similar inverse kinetic isotope effects were observed in both cases, which led to the conclusion that the rate-determining step…
It is demonstrated theoretically and experimentally that the direct and converse piezoelectric coefficients. ∂P/∂σ and ∂ε/∂E, are not equal as is generally believed. The correct relationship between these coefficients is derived, and it is shown that the experimentally measured quantities analogous to the piezoelectri…
The variation of apparent KIc with crack length is being studied using a variety of commercial ceramic materials. Test methodology is much the same as has been used in the past for natural rock (notched bend test). Where sufficiently definitive data have been obtained, each material showed decreasing KIc with decreasi…
Various mechanisms have been invoked in the past to explain the effects of catalysts on the gasification reactions of carbon. However in many cases the observed catalytic behavior can be interpreted in terms of oxidataion‐reduced cycles occurring on the carbon surface. This paper describes how the techniques of therma…
The chemistry of nitroalkanes has been used to develop two rational synthetic routes to the new class of Cmethylated chlorins.
The potential of Fourier-Transform Infrared (FTIR) spectroscopy for characterizing polyethylene terephthalate (PET) fibers is examined both from a practical and a theoretical view point. Problems associated with sample preparation, spectral data analysis, and refraction and reflection at the fiber surfaces are discuss…
A simple single‐extraction procedure for measuring exchangeable cations and effective CEC (ECEC, the CEC at natural pH and ionic strength) has been developed for routine advisory soil analysis. The method is based on the use of Sr (1.26M SrCl2) to displace exchangeable cations and effective CEC is taken as the sum of…
We pyrolyzed PVC with and without the char-promoters iron (III) pyromellitate, zinc pyromellitate, and MoO3 (1 phr) under isothermal conditions (207°C, nitrogen) and analyzed the soluble and insoluble residues to characterize the reactions important to charring. Both pyromellitates, apparently acting as their metal ch…
Abstract Deprotonated N ‐phenyl, N ′, N ′‐dialkylthiourea (PhtuR 2 ) complexes of Cu(I) and Cu(II) have been isolated and the existence of a Cu(III) complex inferred from electrochemical measurements. The crystal structure of Cu(I)[(C 6 H 5 )NC(S)N[(C 2 H 4 ) 2 O]] (space group P l̄, Z = 24, a = 10.487(9), b = 28.961(…
A high-yield six-step synthesis of sequirin D (1a), a naturally occurring norlignan, is described. Michael addition of deoxyanisoin (2) to acrylonitrile gives a ketonitrile (3), which on Wolff–Kishner reduction is reduced and hyrolysed in situ to 4,5-bis-p-methoxyphenylpentanoic acid (4). Cyclodehydration of (4) with…
In aqueous dimethylformamide solution meso-αααα-tetra(o-maleamoylphenyl)porphyrin undergoes rapid metal incorporation (CuII, ZnII, CoII, and NiII) by a mechanism featuring rate-determining intramolecular transfer of the metal ion from the carboxylate binding site to the porphyrin nucleus.
The fact that the polarization-related electrostrictive coefficients Q in the relaxor type ferro-electrics are almost an order of magnitude smaller than in most normal ferroelectric perovskites can be explained under the assumption that the temperature dependence of the soft-mode TO phonon frequency is given as ω2 TO…
—This paper summarizes experimental results obtained during the study of the production of nitrogen oxides in a well stirred reactor burning hydrocarbons. First, the particular problem of NO and NO2 probing has been addressed, and it has been shown experimentally that NO → NO2 conversion actually occurs within the pro…
The metal-insulator transition in Ti2O3 is described as a bandcrossing transition, an electron-hole gas forming when its free energy becomes greater than the gap.
The 13C n.m.r. spectrum of high-spin chloro(5,10,15,20-tetraphenylporphyrinato)iron(III) has been unambiguously assigned using porphyrins isotopically enriched at selected positions. The unexpected linewidth of the resonances of the porphyrin core carbons is explained by the dipolar interaction of the carbon nuclei wi…
The fatigue properties associated with the β1\ ightleftarrowsβ1′ transformation pseudoelasticity cycling of Cu–Al–Ni alloy single crystals have been investigated by cyclic loading tests and fractographic observations. Fatigue life is surprisingly short even under 100 MPa of applied stress, although the static fracture…