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Production of Neutral Photopions as a Function of Atomic Weight

Description: Thesis discussing the relative yield of neutral pions from elements in a reaction "as a function of the quantum-limit energy (the maximum energy of the quanta in the bremsstrahlung beam) of the Berkeley synchrotron." Interpretation of the results leads to values for the mean free path for absorption of the neutral pions in nuclear matter.
Date: May 28, 1956
Creator: Anderson, John David

Solutions of the Reactor Kinetics Equations for Time-Dependent Reactivities

Description: Abstract: The reactor kinetics equations are combined into a single integral equation whose kernel describes the time-dependent characteristics of the reactor including six delayed groups of neutrons. Numerical solutions of the integral equation are given for constant, linear, and ∫sin²kx dx reactivities. An approximate solution of the integral equation is obtained which provides a basis for the formulation and solution of the reactor system control problem using the methods of servomechanisms theory. The reactor frequency response function, a product of the approximate solution, is calculated and plot given.
Date: December 14, 1955
Creator: Ash, Milton S.

Li⁶ and Li⁷ (n. 2n) Cross Sections at 14.1 Mev

Description: Abstract: "An absolute measurement of the 14.1-Mev (n, 2n) cross sections of Li-6 and Li-7 has been made using the large scintillator technique, resulting in cross sections in barns of 0.070 +/- 0.006 and 0.056 +/- 0.005 for Li-6 and Li-7, respectively."
Date: May 29, 1958
Creator: Ashby, V. J.; Catron, H. C.; Newkirk, Lester L.; Taylor, C. J. & Williamson, M. A.

Experiments on Polarization in Scatterig Deuterons from Complex Nuclei and in Proton-Proton Scattering (Thesis)

Description: Abstract: "The elastic double scattering of deuterons by complex nuclei has been investigated experimentally. Measurements were made on carbon, aluminum, and copper at around 157 Mev; on lithium, beryllium, and carbon at around 125 Mev; and on carbon and aluminum at 94 Mev. The expected tensor components of the deuteron polarization have not been observed. Measurements have been made of the differential cross section and vector-type polarization as a function of angle for the scattering of deuterons from the above elements, at the above energies. The observed polarizations were larger than would be expected on the basis of the individual nucleon-nucleus interactions. In a second experiment we measured the 169-Mev proton-proton polarization at 10, 15, 22.5, 30, and 35 in the laboratory system. The results indicate that partial waves up to and including L = 3 are important at this energy."
Date: May 11, 1956
Creator: Baldwin, John A., Jr.

Use of Controlled Photosynthesis for Maintenance of Gaseous Environment

Description: Abstract: "The problem of maintaining livable oxygen and carbon dioxide pressures in a closed space in which men must live leads to consideration of the possible use of the photosynthesis of green algae. A calculation based on the known respiratory rate of man and the photosynthetic rates of Chlorella indicates that it would be feasible to use algae for this purpose."
Date: September 1954
Creator: Bassham, James Alan

Macroscopic Properties of a One-Dimensional Plasma Confined by a Magnetic Field

Description: Abstract: "The quantities of interest in a confined plasma include the electric and magnetic fields, current density, diffusion velocity, temperature, pressure, and particle density. Equations governing the distribution of these seven variables are given in this report and special cases of a one-dimensional steady-state plasma are examined in detail. The solutions are given in graphical form."
Date: September 4, 1956
Creator: Batten, Hugh W. & Woods, Cornelius H.

High Energy Fission and Spallation of Uranium

Description: From introduction: "This report is an attempt to examine, semiquantitavely, the way the competition between neutron emission and fission varies for heavy nuclei as a function of nuclear type and excitation energy. Many of the ideas herein are the results of discussions with R. H. Goeckermann and W. Heckrotte of the University of California Radiation Laboratory."
Date: February 25, 1954
Creator: Batzel, Roger Elwood

The Elimination of Microwave Reflections

Description: Abstract: "The reflections of microwaves from the walls of a plasma-containing vessel are studied. The probable cause of the reflections is discussed, and several suggestions are made for eliminating the reflections from the waveguide in the vessel and particularly from the pyrex vessel wall and copper tubing surrounding the pyrex. Quarter-wave-thick carbon-filled plastics or glasses having a very low vapor pressure room most promising when placed inside the pyrex cylinder. BaTiO3 appears to be an excellent material when placed outside the vacuum."
Date: February 1, 1955
Creator: Beard, David

Influence of Fluorine Substitution on the Properties of Metal Chelate Compounds

Description: From introduction: "This is the first of three articles dealing with the influence of fluorine substitution in the ligand on the properties of metal chelate compounds. Although the primary purpose of this project was to study the influence of fluorine substitution on the properties -- particularly light absorption -- of uranyl compounds, copper chelates were chosen for preliminary study as model substances, because they are easily prepared."
Date: June 9, 1955
Creator: Belford, R. Linn; Martell, Arthur E. & Calvin, Melvin

Pulsed Neutron Experiments With Fast Assemblies

Description: "The pulsed source technique consists of introducing repeated short bursts of neutrons into a subcritical assembly, and following the decay of the leakage flux as a function of time...It is noted that plotting the decay constant as a function of buckling gives an apparently accurate way to extrapolate to prompt critical. The pulsed source technique can also be used to calibrate control rod and poison worth, and will give some estimate of the prompt neutron lifetime."
Date: October 31, 1957
Creator: Bengston, Joel & Passell, Lawrence

Scatterbrain: An Automated Experiment on the 90-Inch Cyclotron

Description: Summary: By controlling certain elements within a vacuum chamber from an external station, a charged particle experiment is performed without opening the chamber, thereby saving considerable time and labor. By pre-programming the experimental sequence on the external controls, the experiment can be performed from beginning to end with a minimum of operator attention. The data collected can be read out automatically on a punched paper tape for subsequent transmission to a digital computer.
Date: October 1956
Creator: Benveniste, J.; Lafranchi, E. A.; Strahl, G. E. & Swenson, R. L.

Gamma Rays from the Interaction of 14-Mev Neutrons with Beryllium

Description: Abstract: "The cross section for the Be-9(n, t')Li-7*-->Li-7 + Y(0.477 Mev) reaction has been measured in the vicinity of 14 Mev by detecting the gamma-rays at scattering angles from 30 to 150 degrees. A time-of-flight technique was used to distinguish the gamma-rays from the high neutron background. The cross section drops from 20 mb at 13.6 Mev to 10 mb at 14.1 Mev and then rises to 30 mb at 14.7 Mev."
Date: June 9, 1959
Creator: Benveniste, J.; Mitchell, A. C.; Schrader, C. D. & Zenger, J. H.

Effect of Boron Liner on Neutron Background in Cavity

Description: Introduction: "In connection with conducting neutron experiments in a pit with earth and concrete walls, it was proposed that the background flux of neutrons might be reduced by lining the walls of the pit with a neutron absorber such as boron. To determine how much liner material would be desirable and what diminution in the neutron background could be expected, the following measurements were undertaken."
Date: January 16, 1953
Creator: Benveniste, Jack

The Metabolism of Chyle Cholesterol in the Rat

Description: Abstract: "Observations on the metabolism of chyle cholesterol in the rat show that exogenous cholesterol entering the systemic circulation in chyle exists in lipoproteins of low density (including chylomicrons) migrating with a high Sf rate (i.e.>400) in the ultracentrifuge. Following entry into the systemic circulation these molecules are rapidly removed from the plasma. This "clearing" of serum chyle cholesterol is a tissue phenomenon, the liver being the predominant site. Within the liver the chyle cholesterol esters are at least partially hydrolyzed; hydrolysis apparently does not occur in the plasma to any appreciable extent. After its entry into the liver exogenous cholesterol, if normally metabolized, presumably mixes with and becomes indistinguishable from cholesterol produced by endogenous synthesis."
Date: May 12, 1954
Creator: Biggs, Max William & Nichols, Alexander V.

Effect of a Decelerating Grid on Current from an Ion Source

Description: Abstract: "A theoretical criterion is given for the conditions under which the ions from an ion source may be decelerated by a decelerating grid, following the accelerating grid which extracts ions from the emitter, without causing a reduction in the current supplied by the source."
Date: February 23, 1955
Creator: Bing, George F., 1924-; Gardner, C. S. & Northrop, Theodore G.