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Minutes of third meeting of committee on use of Nevada Test Site
The Nevada Test Site (NTS) Use Committee met Tuesday morning, May 28, 1957, at Mercury, Nevada. This document provides a summary of the meeting.
SPECIAL HEAT TRANSFER PHENOMENA FOR SUPERCRITICAL FLUIDS
Present-day knowledge concerning the molecular structure of supercritical fluids is briefly reviewed. It is shown that liquid-like and gas-like phases may coexist at supercritical pressures, although they may not be in equllibrium with each other. it is postulated that on the basis of the coexistence of these two phases a "boiling-like" phenomenon may provide the mechanism of heat transfer to supercritical fluids at high heat fluxes and certain other conditions. An unusual mode of heat transfer was actually observed at supercritical pressures during tests which produced the high heat fluxes and other conditions under which such "boiling" would be expected. The tests and the various conditions are briefly described. An emission of high-frequeney, high-intensity sounds usually accompanied these tests. It is shown that similar screaming sounds were heard during boiling at subcritical pressures, giving further support to the hypothesis that "boiling" may occur at supercritical pressures. A seeond possible explanation for the unusual mode of heat transfer is based on boundarylayer stability considerations. At high heat fluxes large density differences exist between the bulk of the fluid and the fluid in the boundary layer near the wall. A breakdown of the boundary layer may be caused by the build-up of ripples between its low-density fluid and the high-density bulk fluid, in a manner quite similar to the breaking of ocean waves at high wind velocities. It is pointed out that the density variation of supercritical fluids may be used to advantage by certrifuging boundary layers. (auth)
Determination of Hafnium and Rare Earths in Aluminum Alloys
Procedures are described for both a titrimetric and a gravimetric determination of hafnium in aluminum -hafnium alloys. The gravimetric procedure is used if the hafnium is to be recovered; otherwise, the titrimetric procedure is preferred. The sample is dissolved in aqua regia. Any undissolved hafnium is taken into solution via pyrosulfate fusion. The hafnium is separated from the aluminum and contaminants in the aluminum by precipitation as the mandelate. In the gravimetric procedure the hafnium mandelate is heated to the oxide, then weighed. In the titrimetric procedure the mandelate is destroyed with nitric, sulfuric, and perchloric acids. The hafuium then is determined by adding a measured excess of EDTA and back titrating the excess EDTA with a standard bismuth solution to a xylenol orange end point. (auth)
The Bevatron
No Description Available.
Fast Electronics in High-Energy Physics
A brief review of fast electronics is given, leading up to the present state of the art. Cherenkov counters in high-energy physics are discussed, including an example of a velocity-selecting Cherenkov counter. An electronic device to aid in aligning external beams from high-energy accelerators is described. A scintillation-counter matrix to identify bubble chamber tracks is discussed. Some remarks on the future development of electronics in high-energy physics experiments are included.
Meeting XI Bevatron Research Conference
It will be desirable to have a general purpose bending magnet available for use with the Bevatron. The design discussed, while tentative, is believed to incorporate most of the desired properties for use with the external beam.
A Separated 1.17-Bev/c K- Meson Beam
This report describes the design and testing of a 1.17-Bev/c separated K{sup -} beam designed in the fall of 1958 in connection with a 15-in. hydrogen bubble chamber experiment. At the target the K{sup -}/{pi}{sup -} ratio was 1/140. At the chamber, 4.0 K{sup -}-meson decay lengths from the target, and after two stages of electromagnetic separation, the K{sup -}/{pi}{sup -} ratio was 12.5, corresponding to a total pion suppression by a factor of about 10{sup 5}. The K{sup -} flux at the chamber was 0.87 K{sup -} mesons per 10{sup 10} protons impinging on the target.
A Separated 1.17-Bev/c K- Meson Beam
This report describes the design and testing of a 1.17-Bev/c separated K{sup -} beam designed in the fall of 1958 in connection with a 15-in. hydrogen bubble chamber experiment. At the target the K{sup -}/{pi}{sup -} ratio was 1/140. At the chamber, after two stages of electromagnetic separation and 4.0 K{sup -}-meson decay lengths, the K{sup -}/{pi}{sup -} ratio was 12.5, corresponding to a total pion suppression by a factor of about 10{sup 5}. The K flux at the chamber was 0.87 K{sup -} per 10 protons on the target.
EXTRATERRESTRIAL LIFE: SOME ORGANIC CONSTITUENTS OF METEORITES ANDTHEIR SIGNIFICANCE FOR POSSIBLE EXTRATERRESTRIAL BIOLOGICALEVOLUTION
In order to decide the value and type of information to be obtained from outer space with regard to its pertinence for the evolution of life, a brief review is presented of the current status of our thinking on the origin of life on earth. This points up the particular kinds of chemicals whose presence, or absence, on other astral bodies might be significant. Heretofore, the only data available are the result of telescopic spectroscopy. We report here information indicating the presence in meteorites of complex organic materials, some of them apparently uniquely pertinent to life processes.
PHASE SHIFTS IN pi+ -p SCATTERING AT 310 Mev
In an experimental program recently completed at the 184-inch synchrocyclotron in Berkeley, data were obtained on elastic {pi}{sup +}-p scattering at a laboratory energy of 310 Mev. Quantities measured were the differential cross section, the total cross section, and the polarization of the recoil protons as a function of center-of-mass angle. We have analyzed the data in terms of S, P, and D waves and have obtained only one acceptable solution. The resultant set of phase shifts is of the Fermi type. The D-wave phase shifts are small but definitely needed to obtain an adequate fit to the data. Owing to the relatively high accuracy of the cross-section data and the inclusion of the results of the polarization experiment, the errors on the small phase shifts have been reduced to less than 1{sup 0}. The differential cross-section and polarization data are given in Tables I and II.
FRACTIONATION OF THE INSOLUBLE MATERIAL OF CHLORELLA CELLS
No Description Available.
THE PHOTOVOLTAIC EFFECT AND PHOTOCONDUCTIVITY IN LAMINATED ORGANICSYSTEMS
As a result of a wide variety of studies on photosynthesis in living plants and plant fragments, together with the development of photosensitive, photovoltaic junctions in inorganic crystals and the discovery and exploration of semiconduction in organic molecular substances, a suggestion has been made that the primary quantum conversion process in photosynthetic tissues involves the creation and separation of charge to opposite sides of an asymmetrically-constructed lamina, followed by the trapping of both the electrons and the holes which then lead to their respective chemical processes, namely reduction of carbon dioxide and oxidation of the water to oxygen. This has led us to study model systems as semiconductors with a view to creating an organic photovoltaic junction.
Investigation of Gamma Sterilization. Final Report for the Period July 1, 1953 through June 30, 1954. Research Report No. 3-54
No Description Available.
Pyrometallurgical Purification of Plutonium Reactor Fuels
Pyrometallurgical methods studied are liquation, self-drossing and filtration, slagging by the addition of oxide, carbide, or halide, liquid metal extraction, complete conversion to halide, followed by filtration and selective reduction of the plutonium, and electrorefininng. Experimental techniques and results are presented for each method. (auth)
Ion exchange properties of hydrous oxides
The large class of amorphous insoluble hydrous oxides has interesting ion exchange properties. These materials have high capacities and suitable exchange rates and may therefore be used in packed columns in typical chromatographic (ion exchange) manner. Hydrous oxides may exhibit either cation exchange or anion exchange properties, or both. The type of adsorption depends on the element on which the oxide is based, on the acidity of the medium and, to some extent, on the ion adsorbed. Though some of the most acidic oxides are soluble (e.g., P/sub 2/O/sub 5/) or easily dispersible (e.g., MoO/sub 3/ WO/sub 3/) their intrinsic cation exchange properties may be utilized by incorporating them in excess into an insoluble matrix, i.e., by preparing certain insoluble acidic salts. Some of the materials with cation exchange properties may be used even with extremely small columns - for the separation of the alkali metals from each other - or of the alkaline earths. The specificity of these compounds for cesium in acidic solutions permits the almost unique isolation of this element from properties all others. Those oxides with anion exchange properties also have unusual selectivities compared with the organic ion exchangers. Oxides based on Bi(III) have high selectivities for the heavier halides and others, such as the oxides of Zr(IV), Nb(V), and Ta(V) for remarkable selectivities for fluorides. (auth)
Aqueous Decontamination of Plutonium From Fission Product Elements
No Description Available.
Radiochemical Studies of the Fast Neutron Fission of U$sup 235$ and U$sup 238$
Radiochemical studies of the fast neutron fission of U/sup 235/ and U/sup 238/ have been made in the mass region beyond mass 143 with two neutron energy distributions. These studies provide measurements of the relative fission yields of several chains in the rare earth group in fission of U/sup 235/ and U/sup 238/ caused by neutrons with an energy distribution very close to unmoderated fission neutrons and by neutrons with an energy distribution peaked at 8 Mev. The increased contribution of very asymmetric modes of fission as the energy of the compound nucleus is increased is clearly shown by the results. In the fission of U/sup 238/ the yield at mass 161 is increased 2.9 times at the higher neutron energy. No previous measurements have been published on radiochemical studies of the fission of U/sup 238/at these neutron energies beyond mass 144 except at mass 156 for the lower neutron energy. (auth)
UTILIZATION OF GROSS FISSION PRODUCTS. SUMMARY REPORT FOR PERIOD FEBRUARY 1, 1952-JUNE 30, 1954
No Description Available.
TEST OF A DIRECT CYCLE NUCLEAR TURBOJET SYSTEM
This paper discusses research and development effort on a direct-cycle air-cooled nuclear reactor and propulsion equipment. The reactor experiment was designed, constructed, and tested during the period 1953 to 1956 to prove the feasibility of operating a turbojet engine from the heat produced by an air-cooled reactor. A description is given of the reactor, turbomachinery, shielding, control system, and associated equipment used in the first propulsion system test which was run in 1956. The system consisted of a modified J-47 turbojet engine arranged so that compressed air from the compressor was ducted through a shielded reactor and a chemical combustor in series before passing through the turbine and exhaust nozzle. The experimental reactor was based on a unique design concept in which water moderated at low temperature is contained in an aluminum core structure. The air-cooled metal fuel elements containing enriched uranium were arranged in passages running through the reactor. Thermal insulation was provided to protect the aluminum structure from the high temperature fuel elements and air, and to reduce heat losses to the moderator water. The entire reactor shield and turbojet assembly was mounted on a four-rail flat car for easy transfer by a shielded locomotive from the test site to the maintenance facility, where reactor disassembly repair and maintenance were performed by use of remotely controlled handling equipment. A description of the test facility with its underground control room, instrumentation, and data processing system is presented as well as a description of the large maintenance facility and various types of remote handling equipment. Test operating experience is presented which includes data on the operating characteristics of the system; the nuclear, thermal, and mechanical behavior; the radiation levels experienced; and the remote disassembling, repairing, and servicing the propulsion system. The paper includes photographs and charts describing the equipment, facilities, …
Graphite radiation damage as a reactor operational problem
Radiation Damage to the graphite moderator has played an important role in the history of reactor operation at Hanford. The operational problems, potential and real, which result from dimensional instability, stored energy, and gasification, as well as the solutions to these problems are discussed. The key to the graphite problems is operating temperature and its control. At present, stack expansion remains in the fringe regions of the original reactors, which coupled with the contraction of the central region gives rise to curvature problems in the top portion of the reactors. Stored energy is not a safety hazard because the release spectrum is such that a spontaneous and self sustained release cannot occur. Oxidation of the graphite moderator is controlled by maintaining operating temperature of the stack such that no significant amount of oxidation occurs.
Catalysts for Recombination of Radiolytic Gases Over Thorium Oxide Slurries
No Description Available.
Some heat transfer and fluid friction experiments with supercritical water
No Description Available.
A Wide Bandwidth Telemetry System
This paper will describe a telemetry system which has a bandwidth of 250 mgacples, the uses to which it has been put and possible future uses.
Fused-Salt Heat Transfer
This paper presents, in two parts, a general discussion of fused-salt heat transfer. The first part is a report on current experimental results with three new salts - an alkali metal-base fluoride, a zirconium-base fluoride, and an alkali metal nitrate-nitrite mixture known as 'HTS'. In the second part fused salts are compared with liquid metals on the basis of their heat transfer effectiveness as reactor coolants. An analysis is presented for a general solid fuel-element reactor which transfers its heat to a fluid boiling on the outside of the heat exchanger tubes. The results show that fused salts can be as good heat transfer media as liquid metals. (auth)
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