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Bibliography
The ultra-structure of the developing eye of Drosophila
Abstract A description is given of the ultra-structure of the eye of Drosophila melanogaster during its development from the imaginal bud of the late larva till it attains its final form in the adult. Six markedly different types of cells develop out of the apparently uniform epithelium of the imaginal bud; namely, co…
Fluorescence and Reflection Spectra of NaI Single Crystals
The fluorescence emission and excitation, reflection, and transmission spectra of 22 different NaI crystal samples grown in crucibles of Pt or quartz under atmospheres of ${\mathrm{N}}_{2}$ or ${\mathrm{H}}_{2}$ or ${\mathrm{H}}_{2}$ plus ${\mathrm{I}}_{2}$ and in some cases containing stoichiometric excess of Na or $…
Hall Effect and Resistivity of Ni-Pd Alloys
The two Hall coefficients and the resistivity of Ni-Pd alloys have been measured from 4\ifmmode^\circ\else\textdegree\fi{}K to room temperature using fields up to 3.1 webers/${\mathrm{m}}^{2}$. The ordinary Hall coefficient is found to decrease in magnitude for small additions of Pd in Ni, but to increase as more Pd i…
Effect of Point Imperfections on Lattice Thermal Conductivity
The consequences of a simple, phenomenological, theory of lattice thermal conductivity with respect to the effect of point imperfections are summarized. The experimental results of Berman et al. on the effect of varying the concentration of ${\mathrm{Li}}^{6}$ on the conductivity of lithium fluoride are analyzed in de…
Dynamics of Radiation Damage
Radiation damage events at low and moderate energies (up to 400 ev) are studied by machine calculations in a model representing copper. Orbits of knock-on atoms are found and the resulting damaged configurations are observed to consist of interstitials and vacancies. Thresholds for producing permanently displaced atom…
A study of polymer film brittleness
Abstract The inability of polymer chains to deform the required amount within the time allowed by a stress‐to‐failure event results in brittle failure. Factors related to brittle behavior of films were investigated. By both conventional and novel testing techniques, stress–time–temperature relationships were studied t…
Evidence for retention of the crystalline‐amorphous ratio of cellulose during heterogeneous acid hydrolysis
Abstract The literature reports that hydrolysis of cellulose under heterogeneous conditions proceeds by an initially rapid attack on the amorphous regions and then a much slower hydrolysis of the ordered regions or “crystallites.” During such hydrolysis, the degree of polymerization (D.P.) of cellulose initially decre…
The Formation of Urethan Foams
Abstract An understanding of the formation of urethan foams involves consideration of the organic chemistry of the reactions leading to gas formation and molecular growth, the colloid chemistry of nucleation phenomena and bubble stability, and the rheology of the polymer system as it cures. Experimental data are not a…
Electrical Properties of Lead‐Barium Niobates and Associated Materials
The electrical properties of materials in the system lead‐barium niobate are described. Particularly useful materials are obtained when between 25 and 50 mole % of lead niobate is replaced by barium niobate. Materials with a 40 to 45 mole % replacement have permittivities of more than 1500 and radial electromechanical…
Preparation and Properties of Scandium Dihydride
Scandium dihydride was prepared and studied. Scandium was outgassed at 800 deg C in a silica tube. The tube was cooled to room temperature and connected to a series of calibrated volumes containing purified hydrogen at slightly below atmospheric pressure. Pressures were indicated on a manometer read by a cathetometer…
Spin-Lattice Relaxation Times in Ruby at 34.6 Gc/s
Measurements of spin-lattice relaxation time in ruby have been made at 34 6 Gc/s by a pulse saturation method at temperatures from 1.4° to 90°K With weak concentrations the values for the first-order transitions (e.g. 22 msec at 4.2°K) are of the same order of magnitude as those reported at lower frequencies, and the…
STRUCTURE OF BRIDGMAN'S BLACK CARBON DISULPHIDE
The infrared spectrum of black carbon disulphide dispersed in a potassium bromide disk has been examined. The blackness and the infrared spectrum are consistent with its being a linear polymer, —(C==S.S) n .
The Barium-Barium Hydride Phase System1
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Barium-Barium Hydride Phase System1David T. Peterson and M. IndigCite this: J. Am. Chem. Soc. 1960, 82, 21, 5645–5646Publication Date (Print):November 1, 1960Publication History Published online1 May 2002Published inissue 1 November 1960https://pubs.acs.org/doi/10.1021/j…
On the growth habits of twinned crystals of polyethylene
Abstract It has been confirmed by means of electron diffraction that lath‐shaped crystals of polyethylene are {110} reflection twins in which the chain molecules adopt a regularly folded conformation. The orientation and habit of the spiral terraces (or steps) which grow on the {001} faces of these crystals through th…
Growth from the Melt. Part II. Cellular Interface Morphology
The microscopic shape of a solid-liquid interface has been examined theoretically for those growth conditions which give rise to a cellular morphology. The method of obtaining a general solution is set forth, and approximate treatments are used to compare the theoretical approach with experimental data. The variation…
Dissociation Energies of Diatomic Molecules
Force constant, dissociation energy, and equilibrium internuclear distance in a sequence of similar diatomic molecules have been found to be related by the expression kere/D0=const. The applicability of this relationship has been shown for eighteen sequences of similar molecules. With the help of this relationship, th…