Materials Literature
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Typical characteristics of various types of service loading are presented as they were discussed during the establishment of standardized test load sequences. Counting methods are reviewed and a simple and powerful algorithm is given to perform rainflow counting and to store the counting results afterwards. Synthesis…
The upward fire spread rates along the rods of six pure metals and ten steels have been studied for wide variations of the oxygen pressure, 0.1 MPa to 10 MPa, the test piece temperature, from room temperature to 1273 K, and the rod diameter, 1 to 3 mm. For the pure metals, aluminum, iron, lead, tin, titanium, and zinc…
A uniform description of the crystal structures of β -Si 3 N 4 and of compounds with the phenakite type structure is proposed, based on the fact that the latter are superstructures of the former. The cation ordering in α -LiGaSiO 4 that leads to space group R 3 is explained in terms of a superstructure of β -Si 3 N 4…
The influence of type of silk, age, and weighting agent on the physical and chemical deterioration of silk fabrics was evaluated by comparing the strength, elongation, amino acid content, viscosity, and infrared spectra of 54 undyed, historic silk fabrics with new silk plain weave fabric. Fiber fracture patterns also…
Tertiary recrystallization was observed after cold-rolling and annealing of conventional silicon steels. The magnetic induction B/sub 8/ at 800 AA/m of tertiary recrystallized sheets about 75- mu m thick is as high as 1.97 T. Magnetic domain width in these sheets is greater than 1 mm; hence domain-refining techniques…
Molybdenum (VI) is shown to replace ‘capping’ vanadium(V) in the decavandate structure, once to yield monomolybdononavanadate [MoV9O28]5–, or twice to yield dimolybdo-octavandates [Mo2V8O28]4–. By potentioemtry and 51V, 17O and 95Mo n.m.r. spectroscopy, including 51V–51V correlation spectoscopy, the speciation and une…
The reactions of silyl radicals R3Si˙(R = Me, CD3, Et, MeO, ButO, or Me3SiO) with aminoboranes R1R2N[graphic omitted]BH2 in solution have been studied using e.s.r. spectroscopy. The silyl radicals add rapidly at low temperatures to 2,2,6,6-tetramethylpiperidinoborane and to N-t-butyl-N-methylaminoborane to give aminyl…
VO2 (A), a metastable phase of VO2, was prepared by hydrothermal treatment of an aqueous VOSO4 solution. (VO2 (A) has tetragonal symmetry but the crystal structure remains unknown. DTA and magnetic susceptibility measurements revealed a transition at 162°C which was detectable on heating but not on cooling. Semiconduc…
Abstract A recently developed analytical technique, modulus profiling, conveniently allows the mechanical properties of elastomers to be mapped with spatial resclutions approaching 0.05 mm. Thus, spatial heterogeneities in modulus caused by processing and aging phenomena can be easily monitored. This paper describes s…
The essential equations of solid–solid nucleation theory are summarised and the origins of the accelerated nucleation kinetics observed at grain boundaries are examined on this basis. Methods of measuring nucleation kinetics at grain boundaries are critically reviewed and the precautions which must be taken in order t…
Abstract Metalloporphyrin-catalyzed reduction of dioxygen by ferrocene derivatives occurs efficiently via outer-sphere electron transfer from ferrocene derivatives to metalloporphyrins (MTPP+), followed by acid-catalyzed reduction of dioxygen by MTPP in the presence of perchloric acid in acetonitrile.
The anisotropy of magnetic properties in non‐oriented electrical steel sheets can be evaluated by measuring Epstein specimens in the radial directions. The magnetic properties measured on ring cores are practically equal to the approximate values of magnetic properties determined by Epstein specimens in the radial dir…
Alloy 718 is extensively used by the oil and gas industry for Critical Service applications involving both wellhead components and downhole auxiliary equipment for corrosive/sour service. This study addresses the metallurgy and precipitation behavior of this alloy and their effects on fracture resistance. The use of h…
Abstract Five new optically active crown ethers and six optically active dipodands are reported. The crown ethers were synthesized by using (+)-(1S,4R,5S,8R)-2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene-4,8-diol and (+)-(1S,4R,5S,8R)-4,8-bis(hydroxymethyl)-2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene as a chiral subunit…
Chlorided Pt/Al2O3 catalysts have been subjected to a series of consecutive oxidation / reduction cycles and the quality of Pt dispersion after each reduction stage monitored by infrared study of adsorbed CO. Low-temperature (613 or 723 K) oxidation treatments failed to improve Pt dispersion after subsequent reduction…
The anomalous high-index faces (hkl) of the mineral calaverite (Au1 - xAgxTe2) measured goniometrically in the year 1931 by Goldschmidt, Palache & Peacock [Neues Jahrb. Mineral (1931), 63, 1-58] are re-interpreted and related to the wave vector q of the displacive incommensurate modulation which was recently found in…
The reactivity towards carbon monoxide of a series of Zn–Cr non-stoichiometric spinels (NSS) with an excess of zinc, active in the synthesis of methanol and higher alcohols, has been investigated by infrared spectroscopy and adsorption microcalorimetry. A fraction of the total CO taken up is irreversibly oxidized to s…
The physical properties of a carpet, especially the mechanical and optical properties, largely determine its performance as a floorcovering. The mechanical properties influence the walking comfort and are closely linked to the changes in appearance during wear. New instrumental techniques, notably those using digital…
Seven novel fungitoxic sesquiterpenoids, chokols A, B, C, D, E, F and G, were isolated from stromata of Epichloe typhina on Phleum pratense. Their structures were determined by spectroscopic methods. The absolute configuration of chokol E was elucidated by its CD spectrum with Eu(fod)3 and a chemical correlation with…
Quality, appearance, and tactile properties of textiles arise from the choices of fibre type, linear density, staple length and degree of crimp, yarn linear density, mass, and twist, and fabric mass, weave type, density, and type of finishing, and especially the types of fibre assembly chosen. Information on how these…