Infrared Spectra of Steroids
CONTENTS I. Features of the chemical structure of steroids 155 II. Correlation of the infrared spectra of steroids with their structure 156 III. Use of infrared spectroscopy in steroid chemistry 164
Materials Literature
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The Masking of Reactions
CONTENTS I. Introduction 142 II. Classification of masking processes 143 III. Methods for calculating the efficiency of masking 144 IV. Masking and the selectivity of reactions 148 V. The most common masking agents 149 VI. Characteristic examples of the practical application of masking 153
Morphometric Variation and Function in the Baculum, with Comments on Correlation of Parts
Probable functions of the baculum are reviewed. Consideration of vectors of resistance of the vaginal orifice and of forces of the baculum reveals possible reasons for the specialization of the bacular tip in some carnivores and rodents. Coefficients of variation of length and some other measurements of some bacula of…
NMR Studies of Diffusion in Glassy and Crystalline Lithium Borates
The 7Li NMR spectra from several lithium borate glasses have been examined as a function of temperature and found to narrow abruptly with increasing temperature in the range of temperatures from 250° to 475°K. The observed narrowing is a manifestation of the phenomenon of motional narrowing, and is attributed to diffu…
Crystal structure of β-Cu2P2O7
The crystal structure of β-CU 2 P 2 O 7 has been determined by X-ray methods. The crystals are monoclinic with a = 6.827(8) Å, b = 8.118(10) Å, c = 4.576(6) Å, β = 108.85(10)°, Z = 2, and space group C2/m. This structure is analogous to that of the mineral thortveitite and the high temperature forms of the pyrophospha…
Optical Properties of Alkali-Halide Crystals
Reflectivity data from single crystals of alkali halides have been obtained in the ultraviolet region of the spectrum where excitonic and low interband transitions occur. Following recent calculations for the band structure of KC1 and KI and basing our analysis on the experimental data, it has been possible to predict…
Multipacting Discharges between Coaxial Electrodes
Experimental evidence is presented to demonstrate the scaling relations of the similarity principle for multipacting as applied to coaxial electrodes with b/a (b and a are the radii of the outer and inner electrodes, respectively) varying between 2.3 and 18.26. The two field configurations considered are: (1) rf volta…
Thermopower in Thin-Film Copper—Constantan Couples
The thickness dependence of the thermal emf of thin-film copper—constantan thermocouples at room temperature and above shows nearly bulklike behavior when the thickness of both elements comprising the thermocouple is greater than ∼1200 Å. The thermal response time of the thermocouples as measured with a pulsed laser b…
Temperature Dependence of Dispersed Barrier Hardening
This paper examines the temperature dependence predicted by theories of dispersed barrier hardening. Most of interaction potentials employed in the theories are similar. It is not possible to select one of several interaction potentials on the basis of an experimentally obtained stress-temperature relationship. This p…
Diffraction Pattern and Structure of Liquid Benzene
The scattering of x rays from the free surface of liquid benzene has been analyzed at 25°C. The diffractometer used was specially designed for the study of liquid structure. Intensity and radial distribution functions have been computed for a model structure and compared to those derived from experiment. The model ass…
Magnetic and Crystallographic Properties of Some Rare Earth Cobalt Compounds with CaZn5 Structure
The magnetic and crystallographic properties of CaZn5-type intermetallic compounds of cobalt and rare-earth elements (including Th) have been investigated. Strong deviations from 1:5 stoichiometry are observed when the rare-earth radius becomes relatively small. Both the saturation magnetizations (4πIs=2360–12 300 G)…
Analysis of Materials by Electron-Excited Auger Electrons
The energy spectra of Auger electrons emitted from many elements and alloys have been observed. Differentiation of the secondary electron-energy distribution by perturbation and synchronous detection techniques, and suppression of the effects of low-energy secondaries, were used to obtain well-defined spectra. The Aug…
Small-Angle X-Ray Scattering from Glassy Carbon
Samples of glassy carbon prepared from two different resins and given different heat treatments have been studied with small-angle x-ray scattering to determine pore structure and concentration. The results of the study are described and discussed after an initial section in which the analytical methods used are defin…
Fracture Behavior of Tubular Bombs
The plastic deformation behavior and modes of fracture exhibited by tubular bomb casings are greatly influenced by the stress state imposed by explosive and inertial forces. These forces combine to produce triaxial compression over a varying inner portion of the tube wall. Noting that compressive hoop stresses would e…
Spectroscopic Studies of Ruthenium(II) Complexes. Assignment of the Luminescence
Absorption and emission spectra of nine (4d)6 ruthenium(II) complexes dissolved in rigid glasses are reported. Tris(bipyridine), tris(o-phenanthroline), bis(tripyridine), and a series of cis-substituted bis(bipyridine) complexes of ruthenium(II) were synthesized. The cis substituents were cyanide, ethylenediamine, pyr…
Theory of Magnetization Ripple in Ferromagnetic Films
In a polycrystalline ferromagnetic film, the magnetization direction is not uniform but exhibits small wave-like fluctuations known as magnetization ripple. In this paper, a general theory of ripple is developed, extending previous treatments by the present author, Hoffmann, and others. The theory is applicable to alm…
Electronic Spectra of Crystalline NaCl and KCl
The real (${\ensuremath{\epsilon}}_{1}$) and imaginary (${\ensuremath{\epsilon}}_{2}$) parts of the dielectric response function, together with the energy-loss function Im ($\frac{1}{\stackrel{^}{\ensuremath{\epsilon}}}$), of freshly cleaved single crystals of NaCl and KCl were obtained in the region 5-28 eV by Kramer…
Electrical Resistivity of Silver Films
The resistivities of epitaxially grown silver films have been measured as a function of temperature from 4.2 to 295\ifmmode^\circ\else\textdegree\fi{}K. Both the temperature-independent residual resistivity and the temperature-dependent resistivity were found to increase with a decrease in the specimen thickness. The…
Plastic Deformation Bands in Glassy Polystyrene
Plastic deformation bands nearly parallel to planes of maximum shear stress have been observed in unoriented glassy polystryene in compression and in preoriented polystyrene in tension and torsion. In the temperature range 77°–375°K, the shear stress for homogeneous nucleation of deformation bands is of the order of a…
Magnetic Properties ofLa0.5Sr0.5CoO3near Its Curie Temperature
Samples of ${\mathrm{La}}_{0.5}$${\mathrm{Sr}}_{0.5}$Co${\mathrm{O}}_{3}$ were prepared, and a study was made of their electrical and magnetic properties. Investigation of the initial susceptibility immediately above the Curie point ${T}_{c}$ determined that the critical exponent $\ensuremath{\gamma}=1.27\ifmmode\pm\e…