Materials Literature
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Radiative recombination in gold, copper, and gold-copper alloys has been observed arising from transitions between electrons in conduction-band states below the Fermi level and holes in the $d$ bands generated by optical excitation.
In the course of fast reactor safety studies various problems associated with the transient boiling of liquid metals have arisen. Some of these of general interest, associated with nucleation, bubble growth and channel voiding, are discussed here. The differences between the behaviour of liquid metals and water are em…
Abstract Crystallinity is, ideally, the fraction or percentage of perfectly crystalline matter in a material which is partially crystalline. Because transition structures can exist, however, measured crystallinity will depend largely on the method used. The differences in the infra‐red spectra of the same substance in…
The new species Halosphaera parkeae (Prasinophyceae) is described from material collected in the western English Channel. The microscopical structure of the outer wall of the non-motile phase is described and two types of punctation are demonstrated. A general account of the cytology of the mature non-motile phase and…
A review of the literature and extensive field interviews have been conducted on the subject of needle heating in high-speed sewing. As a result of this investigation, a survey of the current state of the art and knowledge available in the field has been completed and is presented in the following categories: (1) the…
A rotating crystal x-ray diffraction technique has been employed for the measurement of rotation boundary angles in natural graphite crystals, and the values obtained have been compared with those predicted by coincidence boundary theory. It is shown that for natural graphite crystals these values do not correlate wit…
Experiments which confirm the theoretical predictions on the propagation of magnetoelastic waves in time varying magnetic fields are described. Frequency shifts of spin waves as high as 1 GHz have been observed at L-band microwave frequencies, in axially magnetized rods of yttrium iron garnet (YIG). Experiments with m…
Abstract Die aus Pulverdiagrammen bestimmten Strukturen der Lithiumhalogenid‐monohydrate sind trotz der verschiedenen Kristallsysteme sehr ähnlich. Grundstruktur ist die kubische Zelle von β‐ LiJ · H 2 O ( a = 4.29 6 Å) bzw. der oberhalb 33° vorliegenden Modifikation von β‐ LiBr · H 2 O ( a = 4.02 7 Å). In dieser bild…
An investigation has been made of the occurrence of 25 amino acids in the hydrolysates of five species of diatoms which had been grown in Erd-Schreiber medium. Their distribution pattern in general resembles that found in other species. However, there are characteristic differences; thus, they contain more serine and…
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation D. E. Billing, B. J. Hathaway; Single‐Crystal ESR Spectrum of Bis(ethylenediamine) Copper(II) Nit…
Abstract It was found, using chelating agents and protein denaturants to reduce intercellular adhesion of raw tuber sections, that protein and heavy metals are not important to the integrity of the intercellular cement of mature tubers of the variety Majestic. Using similar techniques, interactions, which might occur…
The metastable orange modification of HgI 2 , described earlier by several authors, was obtained by recrystallization of HgI 2 from 2-chloroethanol in the form of square, platelike crystals ranging in color from red-orange to yellow-orange. The x-ray photographs of the yellow-orange crystals indicated one-dimensional…
The location and function of the five or six sets of silk glands of Araneus diadematus (Cl) are discussed. The structure and function of the three major parts of the ampullate gland indicate a synthesizing, collecting, and possibly structuring section. Two methods of stimulation of the ampullate gland, namely emptying…
Abstract β-Isopropylmalate dehydrogenase, an enzyme involved in leucine biosynthesis, was purified from crude extracts of nutritionally derepressed Salmonella typhimurium. Sedimentation of the enzyme in the ultracentrifuge results in a single, sharp, symmetrical schlieren peak. The s020,w is 5.0 S. Polyacrylamide gel…
Abstract Mechanical relaxation data as a function of temperature (ca. 1 Hz) have been obtained for several samples of isotactic polypropylene crystallized from the melt, which exhibit both α and β forms as well as varying degrees of lamella orientation. The samples ranged in morphology from an unoriented sample showin…
A new and simple modification of the method of expansion in terms of Bessel functions has been developed for the accurate calculation of the potential distributions of cylindrically symmetric electrostatic lenses. The method has been used to give the potential distributions of some double-aperture immersion lenses, an…
Breakdown potentials of hydrogen, methane, ethylene, carbon monoxide, nitrogen and carbon dioxide were measured at room and at elevated temperatures, and oxygen at 296 °K, using mild steel cylindrical electrodes. The gas pressure was varied over a range of almost four orders of magnitude, and the temperature of both t…
ABSTRACT Histological and electrophysiological studies of the spinal nerves, nerve roots and muscles of the abdominal wall of the marine teleost Cottus scorpius have been undertaken to determine the extent and nature of polyneuronal innervation of the fast muscles. Spinal nerves at proximal and distal levels, and the…
Reducing high‐purity BaTiO 3 in hydrogen for 1 h at 1275°C leads to an oxygen deficiency x = 0.0036 in BaTiO 3–x with maintenance of the tetragonal/cubic perovskite‐type structure. Reduction at 1325° C leads to x = 0.0073 and brings about transformation to the hexagonal modification. Up to 1500°C ( x = 0.0233) no furt…
Dislocation velocity on the {1̄21̄2}〈12̄13〉 slip systems of zinc monocrystals was deduced from the rate of growth of slip bands. Near 77°K dislocation velocity is directly proportional to stress, and screw dislocations move more rapidly than edge dislocations. The difference between edge and screw dislocation velocity…