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A Case of Rod Warping

Description: Warping of a rod by a variation in heat transfer coefficient around the periphery is considered. Estimates for some simple cases are given, and a more precise numerical calculation is carried out in ne instance.
Date: May 27, 1944
Creator: Murray, F. & Young, Gale Jay
Item Type: Refine your search to only Report
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Experiments on the Evaporation of Boron in Vacuo : Progress Report No. 1 on a Phase of Problem No. 132 - ML - 56-3; File Serial 13

Description: It was desired to determine a method of evaporating boron to form a rather pure uniform tenacious coat of specified thickness. These coats are needed as monitoring films for neutron intensities, particularly in steel ionization cylinders. The most satisfactory method of evaporating boron employed a graphite filament. A mixture of amorphous boron and Carbenoid A was painted onto the filament which was then heated by electrical resistance method to 2300 degree C at which temperature the boron eva… more
Date: March 31, 1944
Creator: Friel, D. D.
Item Type: Refine your search to only Report
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The Diffusion Length of Thermal Neutrons in Uranium

Description: Measurements made in a uranium cylinder result in a mean value of 1.55 cm. for the diffusion length L for distances of 1 to 4 cm. from the base of the cylinder. Calculations give a value which agrees with the experimental result and show further that L increases from 1.40 to 1.63 cm. as the neutrons diffuse a distance of 5 cm. into the uranium.
Date: May 27, 1944
Creator: Hughes, Donald James, 1915-1960 & Bragdon, E. W.
Item Type: Refine your search to only Report
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Resonance Absorption of Uranium in Mixtures

Description: A good determination of the resonance absorption of uranium when admixed with various substances is necessary so that calculations can be made on the efficiency of homogeneous piles. The original experiments along these lines were undertaken by Creutz, Jupnik, and Snyder (C-116) and consisted of experiments on the resonance capture in pure U, UO2, U3O8, and one experiment on capture in a mixture of U3O8 and graphite. These experiments were done at the cyclotron in Princeton and consisted of det… more
Date: March 31, 1944
Creator: Mitchell, Allan C. G. (Allan Charles Gray), 1902-; Brown, Leon J.; Pruett, John R. & Nering, Evar D.
Item Type: Refine your search to only Report
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Determination on Neutron Density With Bismuth Foils : Final Report - Problem Assignment 131 - X21P

Description: It is usual to determine the density of neutrons by using foils of metals which become radioactive as a result of bombardment in the region under investigation. From the rate of disintegration of the newly formed radioactive element the number of neutrons absorbed can be calculated. By use of the capture cross section of the element of which the foil is composed the density of the neutrons can then be computed. By counting the alpha particles from a bismuth foil of known weight after exposure t… more
Date: May 30, 1944
Creator: Curtiss, Leon Francis, 1895-
Item Type: Refine your search to only Report
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On the Boundary Condition Between Two Multiplying Media

Description: The transition region between two parts of a pile which have different compositions is investigated. In the case where the moderator is the same in both parts of the pile, it is found that the diffusion constant times thermal neutron density plus diffusion constant times fast neutron density satisfied the use pile equations everywhere, right to the boundary. More complicated formulae apply in a more general case.
Date: April 19, 1944
Creator: Friedman, Francis L. (Francis Lee), 1918- & Wigner, Eugene Paul, 1902-1995
Item Type: Refine your search to only Report
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The Influence of Operation on Tuballoy

Description: An attempt is made to estimate the influence of operation upon the mechanical properties of tubealloy. It is to be emphasized that the work is highly speculative, being base upon a set of judicious assumptions regarding the transport material within the metal and should not be used as a substitute for a set of well-planned experiments. The two principal effects considered are the hardening which results from the atomic displacement produced by the fission fragments and the changes in mechanical… more
Date: April 21, 1944
Creator: Seitz, Frederick, 1911-2008
Item Type: Refine your search to only Report
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Resonance Absorption in Lumps and Mixtures

Description: The resonance absorption of a lump is described in terms of three components. Calculations of resonance absorption are carried out using the model for the resonance spectrum of uranium recently derived; calculations are also made with variations of this model which involve local fluctuations in level strengths. For metal and oxide lumps the agreement with observation is satisfactory. For dilute mixtures, whose resonance activation was measured by Mitchell, computed values fall 20% to 30% above … more
Date: April 17, 1944
Creator: Dancoff, Sidney M., 1913-1951 & Gingburg, M.
Item Type: Refine your search to only Report
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The Pile Safety Circuit

Description: The present report is concerned with the electronic relay which, upon the reaching of a pre-determined value of ionization current in the associated chamber, actuates the safety rod release mechanism. The are here proposed two independent suggestions: (1) An improved trip circuit of such sensitivity and stability as to allow it to be actuated by a signal directly from the chamber without the necessity of interposing intermediate amplifier stages. The value of chamber current at which tripping … more
Date: April 14, 1944
Creator: Nierman, Leonard G.
Item Type: Refine your search to only Report
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Calculation of the Temperature Distribution in a Slug With a Solid Aluminum Cap

Description: Calculations were made to determine the temperature at various points of a thick disc and cap, on the assumptions that the heat production rate is uniform throughout the slug and that the slug is in perfect thermal contact with the cap. Results obtained by different methods of computation are compared with each other and with results obtained by Drew on the Paschkis electrical network computer at Columbia University.
Date: April 14, 1944
Creator: Murray, F. H.; Karush, William; Ginsburg, M. & Young, G.
Item Type: Refine your search to only Report
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Eta Temperature Effect

Description: The temperature coefficient of eta has been measured with the thermal column of the Argonne pile using uranium foils of different isotopic ratios. The temperature change was effected by filtering neutrons through silver. The measured fractional change per degree centigrade is [formula].
Date: February 25, 1944
Creator: Bragdon, E. W.; Hughes, D. & Marshall, John
Item Type: Refine your search to only Report
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Radioactivity Induced in Commercial Materials

Description: Six structural materials (aluminum 2S, aluminum 72S, copper, iron, steel, lead and bismuth) were irradiated for about 100 kilowatt hours in the center of the Argonne pile. The alpha and gamma decays were then followed for 130 days on Geiger counters and are presented here graphically as number of rays per minute per gram per kilowatt hour vs. time of decay. A quantitative interpretation of the gamma-ray decay curves gave fair agreement with the chemical analysis of impurities found in the mater… more
Date: February 12, 1944
Creator: Seren, Leo, 1918-; Sturm, W.; Moyer, W.; Miller, G. & Jordan, W.
Item Type: Refine your search to only Report
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Recalculation of the Critical Size and Multiplication Constant of a Homogeneous UO2 - D2O Mixtures

Description: The multiplication constant and optimal concentration of a slurry pile is recalculated on the basis of Mitchell's recent experiments on resonance absorption. The smallest chain reacting unit contains 45 to 55 m3 of D2O.
Date: February 11, 1944
Creator: Wigner, Eugene Paul, 1902-1995; Weinberg, Alvin Martin, 1915-2006 & Stephenson, J.
Item Type: Refine your search to only Report
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Temperature Effect in Homogeneous Pile

Description: Some idealized considerations of the temperature field in the homogeneous pile are given. It is crudely estimated that the effective mean temperature rise of the pile to be used in calculating the k loss is something like 3/4 the rise in temperature of the slurry in passing through the pile.
Date: December 9, 1943
Creator: Young, Gale Jay
Item Type: Refine your search to only Report
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The Resonance Absorption Spectrum of Uranium

Description: A model for the capture spectrum of uranium is introduced in which levels occur at 7, 30, 30+D, 30+2D, ..., ev. Gamma ray and neutron widths are derived from the experimental data for values of D between 10 and 25 ev. The constants of the 7 volt level prove to be independent of D. Extrapolation, using the one level formula, gives a capture cross section at (1/40) ev of 4.9 x 10(24) cm2; this number is, however, quite sensitive to the value taken for the resonance activation. Both neutron and ga… more
Date: November 24, 1943
Creator: Dancoff, Sidney M., 1913-1951
Item Type: Refine your search to only Report
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Some Cases of Pile Activity Flattening

Description: Radial flattening of activity in the cores of spherical and cylindrical piles is discussed in connection with pile control and power improvement. Partial flattening as a result of k loss from temperature rise is also considered.
Date: October 10, 1943
Creator: Morehouse, N. & Young, G.
Item Type: Refine your search to only Report
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The Contamination of Cooling Water by a P-9 Plant

Description: The following sources of contamination in cooling water of the P-9 plant are considered: (1) Fission recoils, (2) Corrosion of metal, (3) Recoil from aluminum, (4) Induced activity in the water. It is found that for a P-9 plant of 3.5 x 10(4) KW contamination of the river at "X" should not exceed the .1 r criterion unless coating failure occurs. Tables of the amount of coating failure permissible are given as a function of holdup time.
Date: June 1, 1943
Creator: Friedman, Francis L. (Francis Lee), 1918-
Item Type: Refine your search to only Report
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The Effect of Fast Fission on k

Description: The importance of fast neutron fission (i.e., fission caused by neutrons before being slowed down) was recognized by Szilard, and calculations similar to the present one have already been carried out by him, Feld, Ashkin, Wheeler, Wigner and others. The purpose of the present paper is to give a general formula for the contribution of fast fission to the multiplication constant, which will include all the cases already considered and will be applicable to more complicated geometries than those c… more
Date: May 4, 1943
Creator: Castle, H.; Ibser, H.; Sacher, G. & Weinberg, Alvin Martin, 1915-2006
Item Type: Refine your search to only Report
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On the Multiplication Constant of Homogeneous Mixtures of U with Various Moderators

Description: The following represents a summary of calculations on the multiplication constant of homogeneous mixtures of uranium and different moderators. These calculations were made possible by Fermi's determination of the age of neutrons and by the extrapolation to higher scattering cross-sections of the resonance absorption of uranium as measured by C. Creutz. According to Fermi, the former quantity is 120 sq. cm. The latter is given in the two attached graphs. The first (Fig.1) of these goes as high a… more
Date: May 16, 1943
Creator: Wigner, Eugene Paul, 1902-1995 & Stephenson, J.
Item Type: Refine your search to only Report
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Effect of Temperature on the Resonance Absorption of Neutrons by Uranium

Description: The resonance absorption of uranium for neutrons has been investigated between 20 degree C and 1000 degree C. Experiments were caried out on both UO2, density 4.63, and metal. The resonance activity was measured with respect to that of an iodine monitor at several different temperatures and the ratio of activity at temperature T to that at 20 degree C was determined. The increase in activity is 0.9 per cent per 100 degree C for the oxide and 1.1 percent per 100 degree C for the metal. The perio… more
Date: April 22, 1943
Creator: Mitchell, Allan C. G. (Allan Charles Gray), 1902-; Slotin, Louis; Marshall, John; Nedzel, V. A.; Brown, L. J. & Pruett, John R.
Item Type: Refine your search to only Report
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Radioactivity of the Cooling Water

Description: The most important source of radioactivity at the exit manifold of the pile will be due to O19, formed by neutron absorption of O18. A recent measurement of Fermi and Weil permits to estimate that it will be safe to stay about 80 minutes daily close to the exit manifolds without any shield. Estimates are given for the radioactivities from other sources -- both in the neighborhood and farther away from the pile.
Date: March 1, 1943
Creator: Wigner, Eugene Paul, 1902-1995.
Item Type: Refine your search to only Report
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