Materials Literature
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Abstract An investigation of the diffusion of electrolytic hydrogen through membranes of: (1) polycrystalline Armco iron; (2) single crystal Armcoiron; (3) zone refined iron; and (4) A.I.S.I. 4340 has been made. The temperature and stress dependence of the permeation rate through (1) and (4) was investigated, while (1…
The hydrogen positions in the crystal structure of copper formate tetrahydrate have been determined, and some new data on the antiferroelectric phase transition at −38.9°C are presented. It is shown that the orientation of the water molecules is disordered in such a way as to permit all possible short 0–0 contacts to…
A study has been made of the interaction of oxygen with samples of zinc oxide and ultraviolet-irradiated magnesium oxide using electron paramagnetic resonance techniques. Adsorption of oxygen at room temperature results in the rapid formation of a radical species, having gxx=2.077, gyy=2.0011, and gzz=2.0073 for oxyge…
A study of Ba2xSr2–2xFeMoO6 solid solutions with the ordered perovskite structure showed that their Curie points increased nonlinearly as the amount of strontium increased while their cell sizes decreased with greater quantities of strontium. By substituting calcium for strontium in Sr2FeMoO6 a decrease in Curie point…
Room-temperature reflectivity measurements of Ca${\mathrm{F}}_{2}$ in the fundamental-lattice-vibration region were obtained between frequencies 200 to 650 ${\mathrm{cm}}^{\ensuremath{-}1}$ and angles of incidence ranging from near normal to 78\ifmmode^\circ\else\textdegree\fi{}. Based on the method of classical oscil…
Neutron diffraction measurements on powder samples confirm that the magnetic moments in MnO are arrayed in ferromagnetic sheets parallel to {111} planes, with neighboring planes coupled in an antiferromagnetic fashion. The long-range order parameter $S$ increases progressively with decreasing temperature below the N\'…
The dc mobility of electrons is considered for scattering by acoustical and optical phonons. It is shown that the vertex terms (ladder diagrams) in the mobility integral can be partially summed to all orders of perturbation theory. These vertex terms are shown to be important for acoustic-phonon scattering. The sum of…
Longitudinal and transverse magnetoresistance has been measured in iron single crystals at 300, 77, and 4.2\ifmmode^\circ\else\textdegree\fi{}K in fields up to 50 kOe. For most field and current directions the magnetoresistance reverses sign between 300 and 4.2\ifmmode^\circ\else\textdegree\fi{}K in both high and low…
M\"ossbauer spectra of ${\mathrm{Fe}}^{57}$ in $\ensuremath{\alpha}\ensuremath{-}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ have been measured as a function of particle size and temperature. Bulk $\ensuremath{\alpha}\ensuremath{-}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ shows a change in the sign of the quadrupole interaction in go…
Abstract In einer Reihe vorangehender Untersuchungen wurde die Herstellung molekulareinheitlicher, phenolischer Mehrkernverbindungen beschrieben. Sie besitzen je Phenolbaustein eine phenolische Hydroxylgruppe, wie systematisch untersuchte Acylierungen sowie Methylierung und Arylierung dieser Mehrkernverbindungen zeige…
Abstract On the basis of optical rotatory dispersion data and other evidence, it was attempted to classify the proteins according to the conformation of their polypeptide chains. Three large groups of globular proteins emerge: 1. proteins with a high α‐helix content, 2. proteins with a low α‐helix content, and 3. the…
Abstract Drei verschiedene Darstellungsverfahren für Graphitoxyd wurden verbessert und die erhaltenen Präparate miteinander verglichen. Das älteste, von Brodie beschriebene Oxydationsverfahren liefert fast weißes, sehr stabiles Graphitoxyd, das sich im Verpuffungspunkt, im Schichtabstand und in seiner spezifischen Obe…
A crystalline solid, formed by oxidation of phthalocyanatomanganese(II) in pyridine, has been identified as phthalocyanatopyridinemanganese(III)-micro-oxo-phthalocyanatopyridinemanganese(III)dipyridinate(C(74)H(42)Mn(2)N(18)O2C(5)H(5)N) byx-ray diffraction methods. This novel molecule consists of two manganese complex…
The influence of the distribution of 235U, 239Pu, and 233U in water on the minimum critical mass, the minimum critical concentration per unit length of cylinder, and the minimum critical mass per unit area of slab surface is calculated. Two energy groups are employed in the calculations with parameters normalized to f…
An extensive survey of the clay minerals and the other mineral colloids of many soils led to the conclusions that the chemical environment that exists in a soil during its development determines the kind of clay minerals that are being formed and that the frequency distribution of the clay minerals and the other miner…
Abstract Changes in the infrared absorption spectrum of ammonium-saturated rectorite on heating suggest that the ammonium cations are hydrogen bonded to water molecules when the mineral is hydrated. Further spectral changes above 300°C indicate that lattice OH groups are perturbed by protons liberated from the decompo…
Abstract A suite of granodiorite samples was collected by dredging from depths of about 1000 m from the walls of Carmel and Monterey submarine canyons, Monterey Bay, California. One surface of each of the various granodiorite slabs was weathered and encrusted with marine organisms. The weathering is maximum at the sur…
This is an electrochemical evaluation of a chemical inhibitor on the corrosion behavior of mild steel (ASTM A-414) in solutions containing 54 percent lithium bromide and 0.2 percent lithium hydroxide at 25 C (77 F). Inhibiting effects of lithium chromate at concentrations up to 3000 ppm were studied. Results are analy…
Abstract Polycarbonates of methyl, ethyl, n‐propyl, n‐butyl, and n‐hexyl 4,4‐bis(4‐hydroxyphenyl)pentanoate and copolycarbonates with bisphenol‐A of 0.5‐0.9 intrinsic viscosity in dioxane were prepared by a homogeneous CH 2 Cl 2 pyridine method and the physical properties determined. Increasing the number of carbon a…
Abstract Bei der Zersetzung von Eu 3 O 4 an feuchter Luft tritt neben Eu(OH) 3 die Verbindung Eu(OH) 2 · H 2 O auf, deren Darstellung und Eigenschaften beschrieben werden. Aus G UINIER ‐Aufnahmen geht hervor, daß Eu(OH) 2 · H 2 O in der rhombischen Raumgruppe C –P2 1 am kristallisiert und mit Sr(OH) 2 · H 2 O sowie Ba…