Materials Literature
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A theory assuming specular scattering of electrons and incorporating nonlocal transverse and longitudinal dielectric functions predicts that a thin metallic film may exhibit anomalous optical properties due to the wave-vector-dependent structure in the longitudinal dielectric function.
Detailed experimental results have been obtained on the reflectivity of both natural and pyrolytic graphite single crystals in the visible and ultraviolet regions. Results have been taken for both $E\ensuremath{\perp}c$ and $E\ensuremath{\parallel}c$ at near-normal incidence, and as a function of angle of incidence fo…
Very unusual and large shifts of the $R$ lines of ${\mathrm{Cr}}^{3+}$ with temperature and applied electric fields were observed. Below the tetragonal transition temperature, these shifts were found to have a behavior similar to that of the reciprocal dielectric constant of SrTi${\mathrm{O}}_{3}$. The electric field…
A detailed account is given of the calculation of the generalized susceptibility functions of Gd, Dy, Er, and Lu using realistic energy bands. These susceptibilities clearly show the influence of the Fermi-surface geometry in determining the helical ordering arrangements of the heavy rare earths, and the ferromagnetic…
A M\"ossbauer-effect study of the low-spin compound ${\mathrm{K}}_{3}$Fe${(\mathrm{CN})}_{6}$ has been carried out under a wide variety of conditions. In concentrated samples, the quadrupole splitting, linewidth, and isomer shift were measured as a function of temperature. The components of the electric-field-gradient…
Sharp-line fluorescence and absorption in the region of 7935 \AA{} were observed in ${\mathrm{Cr}}^{3+}$-doped and undoped SrTi${\mathrm{O}}_{3}$. It is reasonably established that the fluorescence and absorption are due to the $^{2}E\ensuremath{\leftrightarrow}^{4}A_{2}$ transition ($R$ line) of the ${\mathrm{Cr}}^{3…
We optically observe the untwisting and alignment, along an applied magnetic field, of high-pitch cholesteric liquid crystals, mixtures of para-azoxyanisole and cholesteryl esters. The results agree quantitatively with de Gennes's predictions and allow a determination of the twist elastic constant of pure para-azoxyan…
Several cross-linking substances which derive from lysine have been isolated from hydrolyzates of collagen and elastin. This observation suggests that certain lysyl side chains exhibiting enhanced reactivity and unique configuration may participate in cross-linking. In native collagen there is a small family of lysyl…
The effect of molecular interaction between anisotropic (prolate) molecules in liquids on the nonlinear refractive index is studied. The model, without the driving term describing the strong optical-field molecular reorientation, is the same as the Maier and Saupe model of the isotropic to nematic phase transition in…
A Hamiltonian development of the dynamics of the radiation field coupled with an electron gas is presented. The Maxwell equations and the Bloch electron-gas equations are employed in this development. Detailed study is made of first-order coupling between surface plasmons and photons normally incident on a nonuniform,…
The formulation given by Smith et al., for transitions induced by electron impact among ground-state terms of atoms or ions with configurations $2{p}^{q}$ or $3{p}^{q}$, is corrected. Close-coupling equations are solved numerically for electrons incident on C, N, O, ${\mathrm{N}}^{+}$, ${\mathrm{O}}^{+}$, and ${\mathr…
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…