Search Results

open access

Radiocarbon from Pile Graphite; Chemical Methods for its Concentration

Description: Abstract. Samples of pile graphite, irradiated in a test-hole at Hanford for 15 months, have been assayed for radioactive C14, yielding 0.38 ± 0.04 microcuries per gram. At this level of activity, the pile graphite contains very valuable amounts of C14. The relation between the above assay and the probable average assay of pile graphite is discussed, and it is concluded that the latter is almost certainly above 0.3 uc/ gram. Controlled oxidation of this graphite, either with oxygen at ~ 750°C, or with chromic acid "cleaning solution" at room temperature, yields early fractions which are highly enriched in C14. Concentrations of 5-fold with oxygen, and 50-fold with CRO{sub3}, have been observed. The relation between the observed enrichment and the Wigner effect is discussed, and a mechanism accounting for the observations put forward. According to this, about 25% of the stable carbon atoms in the lattice have been displaced by Wigner effect, a large fraction of which have healed the migrating to crystal edges. All the C14 atoms have been displaced, and the same fraction of these migrate to the edges. The enrichment then results from surface oxidation, in the oxygen case. Predictions are made on the basis of this hypothesis. A technique of counting radioactive CO2 in the gas phase is described
Date: October 10, 1946
Creator: Arnold, James R. & Libby, Willard F.
Partner: UNT Libraries Government Documents Department
open access

Recovery of D2O and UO2F2 by Distillation

Description: Technical report describing the purification and separation by distillation of UO2F2 from D2O. In the experiment which is discussed 2,129.6 lbs of UO2F2 were dissolved in 6,605 lbs of D2O. The average isotopic purity of the D2O decreased during the distillation from 99.77% to 99.73%. The dissolved impurities were less than those present originally in the heavy water.
Date: October 10, 1945
Creator: Fischer, R. & Wattenberg, Albert, 1917-
Partner: UNT Libraries Government Documents Department
open access

Analysis of Iron in Thorium, Beryllium, and Cerium

Description: Introduction. the colorimetric determination of iron based on the formation of the colored ferrous-1,10-phenanthroline complex has been used successfully by a number of investigators. In this technical report, its adaptation to the routine determination of iron in cerium, thorium, and beryllium metals and their compounds is described.
Date: September 10, 1945
Creator: Ericson, R. P & Fornefeld, E. J.
Partner: UNT Libraries Government Documents Department
open access

Healing of Fast-Neutron-Induced Changes in Graphite. II. The Effect of Heating During Exposure, Interim Report on Problem 323 MLC 2301

Description: Technical report. The effect of temperature during pile exposure on the fast-neutron-induced change in properties of graphite was studied. Temperatures up to 125 degrees C have no effect upon the rate of increase of elastic modulus; pieces exposed at 300 degrees C on the other hand show no change at all in elastic modulus. The increase in electrical resistance s an inverse function of the temperature of exposure at all temperatures in the range 60 to 300 degrees C.
Date: July 10, 1944
Creator: Neubert, Thomas A.; Novick, A.; Schenck, R. & Shapiro, E.
Partner: UNT Libraries Government Documents Department
open access

Uranium Hydride, a Review to January 1, 1944

Description: Abstract. A review of all work on uranium hydride published in the CC, CT, CN and CE reports to January 1, 1944, is presented. Some additional information not yet published has been included, so this report includes all data known from the above sources and at Ames to the above date. This report supersedes all previous report on uranium hydride coming out of the Ames laboratory.
Date: February 10, 1944
Creator: Newton, A. S.; Warf, J. C.; Johnson, O. & Nottorf, R.
Partner: UNT Libraries Government Documents Department
open access

Reactor Physics, Quarterly Progress Report, August-October, 1953

Description: "A thorough analysis of the data obtained on depleted, natural, and enriched uranium lattices has been made. Consideration of the possible sources of discrepancies between theory and experiment has led to a suspicion of the calculated thermal neutron diffusion lengths. A series of diffusion length measurements in non-multiplying lattices of lead-cadmium alloy has been initiated. An analysis of some early exponential experiments on lattices proposed for a neutron production reactor has been carried out in order to determine whether experimental results on these more complicated structures are consistent with the analysis carried out for the "clean" lattices."
Date: December 10, 1953
Creator: Laubenstein, R. A.
Partner: UNT Libraries Government Documents Department
open access

Energetic Neutral Injection into Thermonuclear Machines

Description: Abstract: "A scheme is discussed in which D+ ions would be accelerated to about 100 kev in a conventional accelerator, then be sent through a gas target frmo which about half the ions would emerge neutral with very little scattering or energy loss; the neutral beam would then cross into a magnetic field and part of the atoms would be ionized and trapped by colliding with the already trapped ions. The smallest mirror machine with a central field of 30-40 kilogauss, 2;1 mirror ratio and β = 01 to 0.5 that would trap most of the neutral beam in the steady state, would be about a meter in diameter and require the order of hundreds of amperes of D+ ions into the neutralizer. The smallest stellerator with a field of 30 kilogauss and β = 0.1 that would trap most of the neutral beam would be about a meter long and require about 10 amperes of D+ ions. A preliminary mirror machine experiment that might be done using the 1/2-ampere, 100-kev D+ beam from the UCRL spare MTA injector is discussed. A method of starting these machine is discussed."
Date: August 10, 1955
Creator: Lauer, Eugene J.
Partner: UNT Libraries Government Documents Department
open access

Uranium Hydride : A Survey

Description: The following report discusses the results of a survey that was initiated to ascertain the availability of uranium hydride in tonnage quantities.
Date: April 10, 1950
Creator: Kitzes, A. S.
Partner: UNT Libraries Government Documents Department
open access

Heat and Free Energy of the Reaction AmCl₃s + H₂O(g) = AmOCl(s) + 2HCl(g)

Description: In a previous paper a method of measuring the equilibrium constants at various temperatures for the titular reaction has been described. This report applies the method to an investigation of the corresponding reaction of americium, representing a part of a systematic program of investigation of the thermodynamic properties of analogous reactions of lanthanide and actinide elements.
Date: November 10, 1952
Creator: Koch, C. W. & Cunningham, Burris Bell, 1912-1971
Partner: UNT Libraries Government Documents Department
open access

Occurrence of the 4n + 1 Series in Nature

Description: "A small quantity of a Np-237, the long-lived ancestor of the 4n + 1 series, has been isolated from a natural source. The Th-229 content of the Th-230 obtained from Belgian Congo pitchblende concentrate and of Th-232 obtained from Brazilian monazite has been determined indirectly through isolation of the Ac-225 daughter. The mass ratio of Np-237 to U-238 in the Belgian Congo pitchblende concentrate has been determined as (1.8 +/- 0.4) x 10-(-12). The mass ratio of U-233 to U-238 in the same ore deposit is found to be (1.3 +/- 0.2) x 10-(-13). The ratio of the respective neutron-capture cross sections of U-238 in the ore body for the (n, 2n) and (n, gamma) reactions is calculated to be (1.3 +/- 0.6) x 10-(-3) on the basis of the relative Np-237 and Pu-239 contents."
Date: April 10, 1952
Creator: Peppard, D. F.; Mason, G. W.; Gray, P. R. & Mech, J. F.
Partner: UNT Libraries Government Documents Department
open access

Effects of Pile Radiation on Be Metal

Description: The following report examines a set of beryllium metal rods through pile radiation, taking measurements, and analyzing differences between irradiated and radiated rod samples.
Date: June 10, 1947
Creator: Siegel, Sidney
Partner: UNT Libraries Government Documents Department
open access

Graphite Sample Boring from Process Channels : Final Report, Production Test 105-389-P

Description: The following report records a total of forty-nine graphite core samples that have been bored from process tube blocks in the Hanford piles with the intention to provide results to indicate that core boring is an entirely practical operation over bore scraping in obtaining powder samples.
Date: July 10, 1951
Creator: Cole, J. B.
Partner: UNT Libraries Government Documents Department
open access

A Model for Radiation Damaged Ductile Metals

Description: Abstract: "A model is presented for radiation damage to ductile metals that accounts qualitatively for the effects of radiation on the electrical and mechanical properties. The model consists of an agglomeration of interstitially displaced atoms into stacking faults in the lattice."
Date: June 10, 1953
Creator: Holden, A. N. & Kunz, F. W.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen