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A Solution of the Distributional Error Problem in Cytophotometry

Description: Use of that portion of the characteristic curve of photographic film in which transmission is linear with log exposure eliminates the distributional error and thus makes possible the assessment of total mass of an inhomogeneously distributed cell consistent without scanning or measuring the cell's projected area. Measurement consists of obtaining the difference in output of a photocell receiving the total light transmitted by a photomicrograph of the cell, and a photomicrograph of the microscope field illumination against which the cell was photographed. A method of making such measurements is given, and its basis is described.
Date: December 19, 1961
Creator: Adams, Lawrence R. & Sondhaus, Charles A.
Partner: UNT Libraries Government Documents Department
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Influence of Different Y Chromosomes on Secondary Nondisjunction in D. Melanogaster

Description: Females heterozygous for a wildtype X chromosome from a Samarkand stock and an chromosome of the composition [formula] were tested for the frequency of X-chromosomal non-disjunction and segregation of the X's when Y chromosomes of different types were present in the females. The Y chromosomes used were 1) a normal unmarked Y, 2) [formula], 3) [formula] and 4) [formula] (a chromosome which arose in one of our experiments and has not yet been analyzed). Since this was only a preliminary test no attempt was made to isogenize the stocks. Larger scale experiments are planned in which these and other Y's will be used and the genetic background will be strictly controlled.
Date: January 18, 1962
Creator: Hildreth, P.
Partner: UNT Libraries Government Documents Department
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The Effect of Temperature on the Yield Strength of the Polycrystalline Hexagonal Ag-Al Intermetallic Phase

Description: The effect of temperature on the yield strength of the polycrystalline hexagonal Ag-Al intermetallic phase was investigated over the temperature range 77 to 775 K. It was found that the curve for yield stress vs temperature for both polycrystalline Ag-33 at .% Al specimens that were heavily cold worked prior to deformation and those that were recrystallized prior to deformation was parallel to that for prismatic slip in single crystals.
Date: December 18, 1961
Creator: Tanaka, Kichinosuko & Mote, Jim D.
Partner: UNT Libraries Government Documents Department
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Hydromagnetic Ionizing Fronts

Description: One of the techniques by which highly ionized plasmas can be generated in the laboratory makes use of strong, electromagnetically driven shock waves propagating into a cold gas. In this paper the phenomenon is analyzed as a one-dimensional single-fluid hydromagnetic problem, neglecting dissipation behind the wave. We hypothesize that the rarefaction wave remains attached to the front. In the limit of essentially complete ionization behind the front the problem can be solved analytically as long as the transverse magnetic field there remains small compared with the longitudinal field.
Date: December 14, 1961
Creator: Kunkel, Wulf B. & Gross, Robert A.
Partner: UNT Libraries Government Documents Department
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The Radiolysis Of Liquid Isobutane With Pulsed Electrons

Description: Of the saturated hydrocarbons, isobutane represents the simplest case where specificity in radiolytic behavior owing to structural configuration should be apparent. The hydrogen bonded to the tertiary carbon atoms should, on the basis of bond strengths alone, be expected to be more reactive than other hydrogen atoms in the molecule. In order to investigate such specificity, liquid isobutane has been irradiated at 20' and an attempt made to identify and measure all products through the C8 (C<sub>8) hydrocarbons.
Date: October 1961
Creator: Yamamoto, B. Y.; Sciamanna, A. F. & Newton, Amos S.
Partner: UNT Libraries Government Documents Department
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A Recoil Study Of The Reaction C12(p,pn)C11 [formula]

Description: Recoil ranges of C11 from the reaction C12(p,pn)C11 are presented for incident proton energies from 0.25 to 6.2 Gev. From these data it is concluded that a neutron evaporation mechanism cannot be the major mechanism. The result for incident energies of 3 and 6.2 Gev are consistent with a fast reaction consisting of a single inelastic nucleon-nucleon collision. Assuming this mechanism, an average kinetic energy of 19 Mev can be deduced for the struck neutron (before the collision) in the C12 nucleus.
Date: October 24, 1961
Creator: Singh, Sarjant & Alexander, John M.
Partner: UNT Libraries Government Documents Department
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Electromagnetic Properties Of A Charged Vector Meson

Description: A systematic study is made of the electromagnetic properties of charged vector mesons. The various formalisms used to describe charged particles of spin 1 are compared, and a new first-order formulation of the Stuckelberg theory is developed.
Date: October 12, 1961
Creator: Young, James A. & Bludmen, Sidney A.
Partner: UNT Libraries Government Documents Department
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The Spectrophotometry Of Metal-Ammonia Solutions At Low Temperatures

Description: Two types of apparatus are described for measuring the absorption spectra of metal-ammonia solutions with the Gary Model 14 Spectrophotometer. One apparatus was used for dilute solutions at -70'; the other was used for more concentrated solutions and had provision for holding the solutions at any temperature between their boiling points and -70'.
Date: December 1961
Creator: Gold, Marvin & Jolly, William L.
Partner: UNT Libraries Government Documents Department
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A Theoretical Consideration Of Asymmetric Heat Flow At The Interface Of The Dissimilar Metals

Description: Several investigators have found that the resistance to heat transfer at certain metal-metal interfaces is dependent upon the direction of heat flow across these interfaces. This paper shows that such a phenomenon can be explained by application of the theory of heat conduction in the solid state.
Date: October 1961
Creator: Moon, Joon Sang & Keeler, R. N.
Partner: UNT Libraries Government Documents Department
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Color Production From Energetic Ions Impinging On Metals

Description: It has been observed that energetic gaseous ions mark their region of impingement on certain metals in color. Under identical conditions of bombardment, multicharged ions of the same gas mark their impact areas with different colors. The colors are sensitive to the type and energy of the ion as well as to the metal bombarded. These colors may result from reflections from thin films formed by reactions at the target. Because the colors indicate that thicker films are produced with increased ion energy, ion penetration depth as predicted by theory is compared with the depth indicated by the colors observed.
Date: June 25, 1962
Creator: Ehlers, Kenneth W.
Partner: UNT Libraries Government Documents Department
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Thermodynamic Properties Of Gaseous Metal Dihalides

Description: The second and third law methods of thermodynamics are used to obtain the enthalpies of vaporization of the halides of Be, Mg, Ca, Sr, Ba, Zn, Cd, Hg, Sn, Pb, Ti, V, Cr, Mn, Fe, Co, Ni and Cu. Molecular and free energy data necessary for such calculations are presented. The structure of bonding in these molecules is briefly discussed.
Date: September 1961
Creator: Brewer, Leo, 1919-2005; Somayajulu, G. R. & Brackett, Elizabeth
Partner: UNT Libraries Government Documents Department
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Nine-Channel Polychromator For Observation Of Time-Dependent Spectral Line Profiles

Description: The instrument (polychromator) described observes time-dependent spectral-line profiles by simultaneous measurement at nine different wavelengths of light intensity as a function of time. A cylindrical lens magnifies the dispersion of a Jarrell-Ash Model S2000 Ebert Monochromator and forms an image on a light-pipe solder. Light pipes transfer light from various sections of the image--i.e., different wavelengths--to photomultiplier tubes, and the responses are displayed on oscilloscopes. The instrument has been used to look at total wavelength spans of 15 A and 20 A.
Date: January 22, 1962
Creator: Spillman, George R. & Cooper, William S., III
Partner: UNT Libraries Government Documents Department
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Sheet Metal Can Furnace

Description: A need for a small vertical cylinder-type furnace arises frequently in the Chemistry Department at the Lawrence Radiation Laboratory (LRL). Adequate heat is the major requirement; close control or calibration is not usually necessary. A heating unit of this type can either be used for quickly concentrating solutions in centrifuge cones or, by the addition of a refractory pedestal--can be made into a crucible furnace for size 0 and 00 crucibles. Because much of the chemistry done at LRL is with radioisotopes, disposal of contaminated equipment is an important consideration. In general, furnaces are difficult to decontaminate, hence there was a need for a disposable type. Because nothing meeting the requirements seemed to be commercially available, the Health Chemistry Department made up a simple furnace that has proved useful.
Date: August 17, 1961
Creator: Doyle, Richard C. & Phillips, Will D.
Partner: UNT Libraries Government Documents Department
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Fabricating Liquid-Hydrogen Targets From Mylar

Description: The increasing popularity of liquid-hydrogen targets in physics research has emphasized the need for containers with maximum beam transparency (i.e., thin walls and low Z) and suitable strength at cryogenic temperatures. Fabrication of a Mylar container satisfying these requirements is described here.
Date: August 17, 1961
Creator: Mehr, David L.
Partner: UNT Libraries Government Documents Department
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Calibration Of Bridgman Anvils, A Pressure Scale To 125 Kbars

Description: It is shown that a radial pressure gradient exists in the silver chloride when it is used as the pressure transmitting medium in Bridgman anvils. The gradient can be obviated by the use of circular sections of wire. The center of curvature of the wire hoop is made coincident with the anvil center. When the inner and outer diameters of the pyrophyllite retaining ring are 1/2 and 7/16" respectively, the pressure, P, is P = (0.725 + 0.468R) L where R is the fractional displacement from the center, and L is the average pressure as determined from the total load and area of the anvil face. The above appears to be valid to 125 Kbars. The Bismuth 6-8 transition is found to accur at 88+3 Kbars.
Date: August 1961
Creator: Montgomery, Peter W.; Stromberg, Harold; Lura, George H. & Jura, George
Partner: UNT Libraries Government Documents Department
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The Crystal Structure Of Cobalt Sulfate Hexahydrate

Description: Calorimetric measurements by Rao and Giauque (1960) showed some unaccountable residual entropy in crystals of [formula] at low temperatures. We have investigated the crystal structure in search of an explanation of the disorder. The resulting structure offers no possibility of disordered rings of hydrogen bonds such as were found in [formula], nor do we find any other explanation of the entropy discrepancy.
Date: August 1961
Creator: Zalkin, Allan; Ruben, Helena & Templeton, David H.
Partner: UNT Libraries Government Documents Department
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Chemical Reactions In Crossed Molecular Beams

Description: Even in its present primitive stage the molecular beam method promises to open up many opportunities for detailed studies of reactive collisions. The early results described here have revealed several features inaccessible to the traditional methods of kinetics. We hope this program of beam studies will ultimately provide the basis for constructing a theory of the molecular mechanics of reactions. By borrowing what are now everyday techniques in nuclear physics (modulation of the beams; mass analysis and counting of detected ions) it appears possible to gain from four to six orders of magnitude.
Date: July 1961
Creator: Herschbach, Dudley R.
Partner: UNT Libraries Government Documents Department
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Semiempirical Correlation Of B<sup>+ Annihilation Rates In Metals

Description: It is shown that the annihilation rates of positrons in metals can be correlated to a good degree by a simple model of the annihilation process based on an assumption that the fractional number of electrons available for annihilation varies as the inverse of the atomic volume of the metal.
Date: July 1961
Creator: McHugh, James A.
Partner: UNT Libraries Government Documents Department
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On Charge Conjugation

Description: It is shown that under very simple and general assumptions the existence of an antiunitary reflection transformation and the charge gauge group implies the existence of an antiparticle corresponding to a given charged particle. Similar consequences follow on replacing the charge gauge group by the baryon gauge group. No assumptions as to specific wave equations, or indeed the existence of local fields, are made.
Date: July 19, 1961
Creator: Case, Kenneth M.
Partner: UNT Libraries Government Documents Department
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The Sideband Technique In A Variable Frequency NMR Spectrometer

Description: The purpose of this Note is to point out the advantages of the sideband technique over the derivative method in wideline NMR spectroscopy. In the sideband technique the absorption spectrum is recorded directly and the modulation amplitude is no longer a determining factor in the resolution.
Date: August 1961
Creator: Acrivos, J. V., 1928-
Partner: UNT Libraries Government Documents Department
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Scattering In The K=O Band Of Odd-Odd Deformed Nuclei

Description: A displacement of energy levels has been observed in the K=O band of odd-odd deformed nuclei. It is shown that this shift is due to a particular type of scattering in which the final state is obtained from the initial state by a rotation of 180'. This circumstance allows one to state certain selection rules on the parts of the n-p residual interaction responsible for the shift. The Wigner component of the force cannot contribute to the shift. In certain cases the contribution of all central forces will be strongly damped allowing observation of the tensor force scattering contribution. Numerical results are presented.
Date: July 1961
Creator: Newby, Neal D., Jr.
Partner: UNT Libraries Government Documents Department
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The Nuclear Spin Of Neodymium-141

Description: The spin of neodymium-141 was measured by the method of atomic beams and found to be 3/2. A lower limit placed on the hyperfine separation of the states with total angular momentum [formula] by second-order perturbation theory shows [formula]. A prerequisite for the determination of the nuclear spin from hyperfine-structure measurements is the knowledge of the electronic structure. The ground-state configuration of neodymium is known and the value is used throughout this work.
Date: July 3, 1961
Creator: Alpert, Seymour S.; Budick, Burton; Lipworth, Edgar & Marrus, Richard
Partner: UNT Libraries Government Documents Department
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A Pulsed Nanosecond Light Source

Description: A system for scintillations from nuclear events has been developed and is presently in use at the Lawrence Radiation Laboratory. This paper primarily describes the pulsed light source used to simulate nuclear events; it also describes the necessary nanosecond pulse techniques to measure the light source parameters and to operate large numbers of lamps. Considerations concerning distribution networks are shown. Use of the light source as a spark gap trigger is also discussed.
Date: August 4, 1961
Creator: Innes, Thomas G. & Kerns, Quentin A.
Partner: UNT Libraries Government Documents Department
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Crystal Structure Of Propionic Acid

Description: The crystal structures of the normal fatty acids of low molecular weight have been rather neglected until recently. Formic acid and acetic acid occur in the solid as hydrogen-bonded linear polymers, while several acids with eleven or more carbon atoms per molecule exist in the solid as dimers. The melting points of these acids, when plotted against number of carbon atoms, fall on two rather similar curves for even and odd numbers of carbon atoms, respectively, each with a minimum near five carbon atoms. These facts and hope of explaining the melting-point behavior led us to examine the structures of propionic and butyric acid crystals. These crystals have different structures, but both contain dimers.
Date: May 23, 1961
Creator: Strieter, Frederick J. & Templeton, David H.
Partner: UNT Libraries Government Documents Department
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