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Description: Experimental instrumentation was tested on Operation Upshot-Knothole in an endeavor to improve existing blast phenomena measuring equipment and techniques. Experimental designs tested include a field unit oscillatoramplifier using transistor circuit elements, a subminiature two-wire field unit, a commercially developed Vibrotron gage and amplifier unit, and a frequency deviation multiplier circuit for obtaining increased signal-tonoise ratios. The Wiancko pressure gage was also evaluated more fully. The results of the tests are described. Transistor circuitry was found to be little affected by atomic blast phenomena. (M.P.G.)
Date: February 1, 1955
Creator: Petes, J.; Little, C.C. & Dossey, J.L.
Partner: UNT Libraries Government Documents Department

Observation of Antiprotons

Description: One of the striking features of Dirac's theory of the electron was the appearance of solutions to his equations which required the existence of an antiparticle, later identified as the positron.
Date: October 19, 1955
Creator: Chamberlain, Owen; Segre, Emilio; Wiegand, Clyde & Ypsilantis,Thomas
Partner: UNT Libraries Government Documents Department

The New ELement Mendelevium, Atomic Number 101

Description: We have produced and chemically identified for the first time a few atoms of the element with atomic number 101. Very intense helium ion bombardments of tiny targets of 99{sup 253} have produced a few spontaneously fissionable atoms which elute in the eka-thulium position on a cation resin column.
Date: April 4, 1955
Creator: Ghiorso, A.; Harvey, B.G.; Choppin, G.R.; Thompson, S.G. & Seaborg, G.T.
Partner: UNT Libraries Government Documents Department

Synthesis and Metabolism of Carbonyl-C14 Pyruvic andHydroxypyruvic Acids in Algae

Description: 1. Pyruvic and hydroxypyruvic acids a r e metabolized by Scenedesmus. 2. The products of metabolism of pyruvic -2 -C{sup 14} and hydroxypyruvic-2 -C{sup 14} acids a r e essentially identical to those of C{sup 14}-O fixations. 3. Lipids a r e rapidly formed i n the light from both substrates. In the dark the major products a r e intermediates of the tricarboxylic acid cycle. 4. Zt does not appear likely that f r e e hydroxypyruvic acid is a photosynthetic intermediate, 5 . Tricarboxylic acid cycle intermediates a r e formed from exogenous pyruvate a s fast in the light a s in the dark.
Date: March 30, 1955
Creator: Milhaud, Gerhard; Benson, Andrew A. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Lifetime of K Mesons

Description: No abstract prepared.
Date: October 1, 1955
Creator: Alvarez, Luis W.; Crawford, Frank S.; Good, Myron L. & Stevenson,M. Lynn
Partner: UNT Libraries Government Documents Department

The Effect of Coenzyme A on the Metabolic Oxidation of LabeledFatty Acids: Rate Studies, Instrumentation, and Liver Fractionation

Description: The effect of pantothenic acid deficiency on the rate of C{sup 14}O{sub 2} excretion and on distribution of radioactivity in liver fractions has been studied in rats given sodium acetate-2-C{sup 14} and sodium heptanoate-7-C{sup 14} The rate of excretion of breath C{sub 14}O has been measured by use of a method in which a sensitive ionization chamber and electrometer directly and continuously record carbon-14 excretion. The labeled fatty acids are more rapidly metabolized to C{sup 14}O{sub 2} in PAD rats than in normal rats. CoA depresses the C{sup 14}O excretion 2 in both normal and PAD rats in experiments with either labeled acid. There are differences in the oxidation of these two fatty acids, and the differences are consistent with postulated metabolic schemes. CoA increases radioactivity deposited in the fat of the liver, but does not appreciably change the radioactivity incorporated in the protein and nonsaponifiable lipid fractions.
Date: April 18, 1955
Creator: Tolbert, B.M.; Hughes, Ann M.; Kirk, Martha R. & Calvin, M.
Partner: UNT Libraries Government Documents Department

S-Acyl Thioctic Acid Derivatives in Aerobacter Aerogenes andScenedesmus

Description: 1. Acetyl thioctic acid has been prepared chemically and i t s chromatographic and acetylating behavior i s described. 2. A C{sup 14} -containing substance has been found in Scenedesmus, photosynthesizing in the presence of a-C{sup 14}-pyruvate, which has properties suggesting that it i s acetyl thioctic acid. 3 . A C{sup 14}-containing substance has been found in Aerobacter aerogenes, metabolizing a-C{sup 14}-pyruvate, which shows the properties of a labile conjugate of thioctic acid with some relatively polar groups. 4. Acetyl thioctic acid i s formed in vitro when light acts on a solution of thioctic acid and pyruvate.
Date: March 30, 1955
Creator: Milhaud, Gerard; Benson, Andrew A.; Fuller, R. Clinton; Milhaud,Vera & Calvin, M.
Partner: UNT Libraries Government Documents Department

High-Current Accelerators

Description: No abstract prepared.
Date: September 11, 1955
Creator: Lawrence, Ernest O.
Partner: UNT Libraries Government Documents Department

High Energy Physics

Description: Without a little further explanation the title of this article may not convey a definite meaning to all readers, so I would like to start by pointing out that ''high energy'' refers to the energy of individual bombarding particles used to produce nuclear disintegrations, and not to situations where a large aggregate amount of energy is involved, as in an atomic power plant. The next question might be, when is energy considered ''high?'' To discuss this, we need a scale for measuring particle energies, and some feeling for the meaning of magnitudes on this scale. The basic scale unit is the ''electron volt'', which is the amount of energy acquired by a particle bearing an electric charge equal to that of an electron, when it falls through an electrical potential difference of one volt. This unit is rather small for use in nuclear physics, so a million electron volts, abbreviated ''MeV'', is the commonly used unit.
Date: January 1, 1955
Creator: McMillan, Edwin M.
Partner: UNT Libraries Government Documents Department

Chemical Evolution and the Origin of Life

Description: A discussion is presented of the elements, or at least most of the elements, that are usually thought of as required and characteristic of living materials. A continuous evolutionary process is conceived, beginning with a bare earth and leading to the random formation of more or less complex molecules from simple ones, and gradually, by the processes of random variation, autocatalysis, and selection, to more complex systems and the ordered array of desoxynucleic acid molecules which are the units that carry the continuity and order of present-day living systems.
Date: August 11, 1955
Creator: Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Particle Accelerators

Description: In the most general sense, an accelerator is any device designed to give kinetic energy to ions or electrons. According to this definition the earliest cathode ray and canal ray tubes, made before the turn of the century were accelerators, the same principle is used in the x-ray tube, the cathode ray oscilloscope, the mass spectrograph, the electron microscope, and many other modern devices. However, we shall limit this discussion to those accelerators made for the particular purpose of inducing nuclear reactions, and to a few others that may be of interest in this connection, although they were originally designed for other purposes, such as high-voltage x-ray tubes intended for deep therapy or the radiography of metals. Although much work related to accelerators is thus omitted, it must not be forgotten that the principles learned and the practical experience gained by this work were of great importance in the development of the machiens now used in nuclear physics.
Date: January 1, 1955
Creator: McMillan, Edwin M.
Partner: UNT Libraries Government Documents Department

The Relation of Quantum Requirement in Photosynthesis toRespiration

Description: 1. The r a t e s of photosynthesis and subsequent respiration of Chlorella pyrenoidosa were measured using an oxygen analyzer (sensitive to paramagnetism). The energy absorbed during the photosynthesis periods was determined and the quantum requirement was calculated. 2. Dark respiration r a t e was found to depend on the r a t e of light absorption during the period of photosynthesis, and increased with increasing photosynthesis rate. 3 . The quantum requirement, corrected for respiration, varied from 4. 9 ( a t a ratio of photosynthesis to respiration of 1.4) to 6. 9 (at a r a t i o of 12). Both uncorrected and corrected quantum requirements approach an experimental value of 7. 4 a t high light intensity. 4. The lower quantum requirement obtained a t low light intensity is believed to be due to a relatively greater importance of contribution of energy from respiration t o photosynthesis. An expression i s derived for the relation between this contribution and the enhancement of dark respiration due to the level of photosynthesis to which the plants a r e conditioned. 5. Attempts to obtain the blue -light stimulation of photosynthesis with algae photosynthesizing in r e d light were unsuccessful.
Date: January 21, 1955
Creator: Bassham, James A.; Shibata, Kazuo & Calvin, M.
Partner: UNT Libraries Government Documents Department

Standardization of Industrial Nuclear Power Plant Components and of Low Power Reactor Systems Report for 1954: Studies Conducted Under an Agreement with the United States Atomic Energy Commission, February 1954 - January 1955

Description: From objectives: This report is a comprehensive review of the American Machine & Foundry Company's Industrial Participation activities for the fiscal year of 1954 and includes a detailed description of technical findings, results of economic analysis and an orientation of the project plans for continued studies.
Date: February 1955
Partner: UNT Libraries Government Documents Department

A Conceptual Study of a 100 kw Gas Cooled Reactor Power Plant for a Remote Location

Description: From introduction: This report details the conceptual design of a 100 kw gas cooled reactor power plant of the type that would satisfy the electrical and space heating load of the Air Force distant early warning stations and might find application at other remote bases.
Date: May 31, 1955
Creator: Frankfort, J. H. & Thompson, W. I.
Partner: UNT Libraries Government Documents Department


Description: Heat transfer coefficients were determined for the eutectic mixture LiF- KF-NaF (Flinak) flowing in forced convection through circular tubes. Heat, electrically generated in the tube wall was transferred uniformly to the fluid during passage through small-diameter tubes of nickel, Inconel, and 316 stainless steel. The variables involved: Reynolds modulus (N/sub R//sub e/), 2300 to 9500; Prandtl modulus (N/sub P//sub r/, 1.6 to 4.0; average fluid temperatures, 980 to 1370 deg F; and heat flux, 9,000 to 192,000 Btu/hr-ft/sup 2/. Forced-convection heat transfer with Flinak can be represented by the general correlation for heat transfer with ordinary fluids (0.5 < N /sub P//sub r/< 100). The existence of an interfacial resistance in Flinak-Inconel systems was established and its composition determined. Preliminary measurements of thermal conductivity and thickness of film were made. The results verify the effect of the film on Flinak heat transfer in small-diameter Inconel tubes. Thermal entry lengths, determined from variations of local heat transfer coefficients in the entrance of the heated section, were correlated with the Peclet modulus. (auth)
Date: February 16, 1955
Creator: Hoffman, H.W. & Lones, J.
Partner: UNT Libraries Government Documents Department

Bevatron Operation and Development. V

Description: A considerable number of major improvements have been made in experimental facilities this quarter. These include four targets, three air locks, a deep well, and several thin windows for beam extraction in the target area. Simultaneous operation of up to five experiments has been achieved with a relay-controlled automatic operations selector. A beam-amplitude regulating device has been used to set the beam level on any pulse to within a few percent. The range of this equipment is 1000:1. Experimentation on the accelerator this quarter included measurements of start frequency and frequency-tracking jitter, beam-versus-radial-aperture measurements, empirical study of gas scattering effects, and preliminary testing of an automatic beam-controlled frequency-tracking system. High-energy physics experiments have been performed by ten groups within this laboratory. These groups are using counter techniques for the elastic proton-proton scattering, K-particle half-life determination, and {pi}{sup -}-meson cross-section measurements. A high-pressure hydrogen diffusion chamber is being used to study multiple production of {pi}{sup -} mesons. A strong-focusing pair spectrometer has been used to produce beams of K particles. Emulsion exposures have been made to determine the masses and mean lifetimes of K mesons. The interactions and modes of decay of K{sup {+-}} mesons at rest, as well as in flight, have been studied in emulsions.
Date: August 24, 1955
Creator: Lofgren, Edward J. & Heard, Harry G.
Partner: UNT Libraries Government Documents Department