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On the Three-Dimensional Instability of Laminar Boundary Layers on Concave Walls

Description: Memorandum presenting a study of the stability of laminar boundary layer profiles on slightly curved walls relative to small disturbances, in the shape of vortices, whose axes are parallel to the principal direction of flow. The result in an eigenvalue problem by which, for a given undisturbed flow at a prescribed wall, the amplification or decay is computed for each Reynolds number and each vortex thickness.
Date: June 1954
Creator: Görtler, H.
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AN INVESTIGATION OF THE ISOTOPES OF AMERICIUM AND CURIUM

Description: Isotopes of americium and curium with mass numbers less than 242 have been produced by cyclotron bombardment techniques, and several of their nuclear properties have been investigated. The partial alpha half-lives of Am{sup 239}, Cm{sup 241}, and Cm{sup 240} and the partial half-life for spontaneous fission of Cm{sup 240} were measured. The alpha decay daughter of Cm{sup 238} was found and evidence for the discovery of Am{sup 237} (an {approx}1 hour electron capture activity) and Cm{sup 239} (a… more
Date: June 1, 1952
Creator: Higgins, Gary Hoyt.
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STUDIES IN THE NUCLEAR CHEMISTRY OF PLUTONIUM, AMERICIUM, AND CURIUM AND MASSES OF THE HEAVIEST ELEMENTS

Description: Ion exchange column elution methods for the separation of americium and curium using tartrate and lactate solutions have been developed which are superior to citrate elutions. Tartrate elutions are suitable for slow separations and lactate elutions are satisfactory for general use where rapid separations are required. Fission and spallation products were isolated from Pu{sup 239} targets which had been bombarded with alpha particles of 21 to 37 Mev energy. Fission yield curves as well as fissio… more
Date: April 20, 1954
Creator: Glass, Richard Alois
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Thermodynamic Properties of Dilute Aqueous Hydrochloric Acid Solutions at Elevated Temperatures From Electromotive Force Measurements

Description: BS>Results of a study of thermodynamic properties of aqueous hydrochloric acid solutions are presented. A hydrogen electrode was used against a silver-silver chloride electrode at 25 to 275 deg C using hydrogen pressure of about 1 atm. and hydrochloric acid concentrations of 0.005 to 1.0 M. Electromotive measurement techniques are described and resulting data are tabulated. (J.R.D.)
Date: May 1, 1959
Creator: Greeley, R. S.
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Hydrodynamic Aspects of Boiling Heat Transfer

Description: A study concerned with the determination of the limiting hydrodynamic conditions which characterize nucleate and transitional boiling was conducted. The critical heat flux and the minimum heat flux are derived from these hydrodynamic limits. Results of investigations of nucleate boilin g are discussed and the theory of bubble growth is extended to include the effect of non-uniform temperature fields. An equation is derived for the product bubble diameter times frequency of bubble emission, and … more
Date: June 1, 1959
Creator: Zuber, N.
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Nuclear Spin and Hyperfine-Structure Measurements on the Radioactive-Iodine and Astatine Isotopes

Description: Atomic-beam magnetic resonance techniques were used to measure the nuclear spins of I/sup 123/, I/sup 124/, I/sup 126/, I/sup 130/, I/sup 132/, I/ sup 133/, I/sup 135/, and At/sup 211/. Also, measurements of the magnetic-dipole interaction constant, and the electroquadrupole interaction constant, and the electroquadrupole interaction constant for I/sup 131/ and I/sup 132/ are reported. The design of the atomic-beam apparatus is described. Experimental methods and sample preparation are discusse… more
Date: August 1, 1959
Creator: Garvin, H. L.
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Range and Range Straggling of Heavy Recoil Atoms

Description: The range and range straggling of 96.8-kev Ra/sup 224/ recoil atoms produced by alpha decay of Th/sup 228/ have been measured in H/sub 2/, D/sub 2/, He, N/sub 2/, Ne, and Ar by a charged, parallelplate, collection technique. The range and range straggling of 725-kev Th/sup 226/ recoii atoms produced by bombardments of Ra/sup 226/ with 41.6-Mev helium ions have been measured in D/sub 2/, He, N/sub 2/, and Ar by this same technique. Experimental results seem to indicate that the range-energy rela… more
Date: November 1, 1959
Creator: Valyocsik, E. W.
open access

High-Energy Beta Decay of Light Elements

Description: The beta decay of the radioactive members of the mass-eight and -twelve triads has been studied with a spiral-orbit spectrometer having a 1.3% resolution. The end point, half-life and log-ft values respectively are: for N{sup 12}, 16.37 {+-} 0.06 MeV, 11.43 {+-} 0.05 milliseconds, and 4.17; for B{sup 12}, 13.40 {+-} 0.05 MeV, 20.6 {+-} 0.2 msec and 4.11; for B{sup 8}, 14 MeV (broad), 0.75 {+-} 0.02 sec, and 5.72; and for Li{sup 8}, 13 Mev (broad), 0.87 {+-} 0.01 sec, and 5.67. The mass excesses… more
Date: June 16, 1958
Creator: Vedder, James F
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CHEMISTRY OF +1 IODINE IN ALKALINE SOLUTION

Description: The iodine species formed either by adding hypochlorite to a basic iodide solution or by adding triiodide to sodium hydroxide, was identified as hypoiodite ion. The absorption spectrum of IO{sup -} was investigated in the wavelength range from 450 m{micro} to 280 m{micro}. The kinetics of the reaction I{sup -} + ClO{sup -} = IO{sup -} + Cl{sup -} was studied spectrophotometrically in alkaline solution. The forward rate law was found to be d(IO{sup -})/dt = k(I{sup -})(ClO{sup -})/OH{sup -}. At … more
Date: June 2, 1958
Creator: Chia, Yuan-tsan.
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ANALYSIS OF THE INTERACTION OF 300-Mev NEUTRONS WITH XENON

Description: An investigation of the interactions between 300-Mev neutrons and xenon was made by means of a cloud chamber in a pulsed magnetic field of 21,700 gauss placed in the neutron beam of the 184-inch Berkeley cyclotron. Eighty-seven negative pion events and 257 other stars were analyzed. In addition an experimental check was made on the energy of the incoming neutrons. Classification, identification, and angular and energy distributions of prongs associated with all events are presented. Interpretat… more
Date: October 17, 1956
Creator: Morris, Richard Herbert.
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Sanitary Engineering Aspects of Long-Range Fallout from Nuclear Detonations

Description: From abstract: Results of a study of the sanitary engineering aspects of fallout from nuclear weapons are reported. Data were obtained from: a. Weekly surface water samples from 22 stations on streams and reservoirs in Eastern Massachusetts, collected from March, 1952 to July, 1953, and assayed for radioactivity. b. Weekly rain samples from March to July, 1953. c. Stream mud and soil samples collected before and after a large fallout. d. Results of fallout activity measurements by others based … more
Date: 1955
Creator: Bell, Carlos G., Jr.
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The Nuclear Spins and Magnetic Moments of Certain Gold and Silver Isotopes

Description: An atomic-beam magnetic-resonance apparatus operating on the flop-in principle was used to measure the nuclear spins and hyperfine-structure separations of the /sup 2/S/sub 1/2, electronic ground state for several radioactive isotopes of silver and gold. The results of these experiments, together with calculated values of the nuclear magnetic-dipole moments, are given (auth)
Date: June 1, 1959
Creator: Ewbank, W. B.
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Scattering of K<sup>+</sup> Mesons Off Protons

Description: The total K/sup +/-p cross section was measured at the three K/sup +/- meson energies 175 er inch per 25, 225 er inch per 25, and 275 er inch per 25 Mev and the differential scattering cross section was measured at 225 Mev. The K/sup +/-p nuclear force was shown to be repulsive from the observed constructive interference with Coulomb scattering. The differential c=oss section was otherwise isotropic and could arise from either pure S-wave or pure P- wave scattering. Subtracted dispersion relati… more
Date: May 14, 1959
Creator: Kycia, Thaddeus F.
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