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Planar Dynode Multipliers for High-Speed Counting

Description: Technical report discussing a new high-speed electron multiplier using a planar dynode configuration. This multiplier has a total transit time significantly shorter than available in conventional structures of equivalent gain. It also features rise-times generally less than three nanoseconds while providing the large sensitive area of an unfocused configuration. Two basic types of planar dynodes are employed: transmission secondary emission thin films as the early multiplier stages and silver-magnesium modified mesh multipliers as the high current output stages.The relevant gain and pulse-response data for these two types of dynodes are presented. The structure is quite flexible and permits the number and types of dynodes to be easily tailored to a specific application. In particular it will be shown how the number of mesh-type dynodes may be altered to effect a trade-off between current handling capabilities and rise-time characteristics. Several possible combinations of these planar dynods have been incorporated in photomultipliers whose gain, dark current, pulse response, and operating life are discussed.
Date: February 26, 1964
Creator: Sapp, W. W. & Sternglass, Ernest J.
Partner: UNT Libraries Government Documents Department

Approximate Models for Distributed-Parameter Heat-Transfer Systems

Description: Summary: The use of dimensionless-parameter frequency response diagrams to determine accuracies of lumped-parameter approximations is demonstrated by two examples: calculation of the heat flux at the surface of a semi-infinite solid due to temperature fluctuations of an adjacent fluid; and the response of a counterflow heat exchanger to inlet fluid temperature perturbations. Dimensionless system parameters make it possible to use general-purpose plots to find the error in particular approximations as a function of the frequency of perturbation. Such plots are directly applicable to control-system stability problems, where the highest frequency of interest is usually apparent.
Date: August 20, 1963
Creator: Ball, S. J.
Partner: UNT Libraries Government Documents Department

Current-Carrying Capacity and Transition State of Superconducting Solenoids

Description: Montgomery and Chandrasekhar and Hulm suggested models for predicting Im and Hm of high-field superconducting solenoids. Montgomery's model for predicting the degradation effect of superconducting solenoids leads to a unique coil quenching characteristics if geometrically similar solenoids are considered. Experiments do not verify these predicted results. Chandrasekhar and Hulm's model leads to one unique coil quenching characteristic for all solenoids with identical wire type and turn distance; coils with identical load factor should display identical values im and Hm. An analysis of the surface currents in an ideal superconducting infinitely long solenoid demonstrated possible forms of shielding currents. Experiments with Pb coils with and without NbZr and compensation agree with results expected from this analysis, but contradict Chandrasekhar and Hulm's model. Measurements of individual turn resistances show behavior of a soft superconductor solenoid in the intermediate state.
Date: September 3, 1963
Creator: Gauster, W. F. & Coffey, D. L.
Partner: UNT Libraries Government Documents Department

The X-Ray Spectra of the Last-Row Elements

Description: Abstract: X-ray energy level diagrams as given in the literature are tabulated for radium, thorium and uranium. A level scheme for protoactinium is derived from the published data. After a brief review of the use of X-ray data in studying outer electronic structure, it is pointed out that differences in the X-ray spectra should exist depending on whether the outer electrons are in f or d orbitals. The observed separation of the OI and OII levels in thorium and uranium indicated that the f levels lie lower than the d. This hypothesis also provides a reasonable explanation for the observed differences between the MIV and MV absorption edges and MIV and MV levels calculated from the emission spectra and the LIII edge.
Date: October 22, 1946
Creator: Russell, H., Jr.
Partner: UNT Libraries Government Documents Department

Electronic Data Processing an Application to Nuclear Materials Management

Description: Abstract: This report is concerned with the application of an electronic data processing system to the unique combination of scientific and commercial data processing requirement of nuclear materials management. The organization and flow of data from the plant through the data processing equipment to the final report is the principle topic of the report. Included in the discussion, however, are topics concerned with the impact of conversion to electronic data processing on personnel, materials management costs, and on other plant organizations. Portions of the report are devoted to programming systems and decision-making abilities of data processing equipment which make these systems readily adaptable to nuclear materials management.
Date: 1963
Creator: Hudson, J. F.
Partner: UNT Libraries Government Documents Department

Some Studies of the Reactions of Uranium Oxides with Hydrogen, Oxygen and Water

Description: Abstract: The purpose of this research was to obtain data that would be useful in predicting changes that might be expected to occur in the oxidation state and degree of hydration of powdered uranium oxides maintained for long periods of time at temperatures between 30 and 300 degrees C. in the presence of excess water, hydrogen, oxygen and possibly hydrogen peroxide. The reaction of hydrogen and oxygen with water slurries of U3O8 were studied at 100-300 degree C.
Date: June 1946
Creator: Gillies, Daniel M.
Partner: UNT Libraries Government Documents Department

Propagation Characteristics of Capillary Ripples, III. Capillary Ripple Velocity and Attenuation Dispersion on Clean Water Surfaces and on Various Monolayers

Description: From Abstract: "The theory and instrumentation previously described by us were applied to the systems monolayer-free distilled water; stearic acid, mixed hexadecanol and octadecanol and several long chain fatty ester monolayers; stearic acid - polyvinyl acetate mixed films and egg albumen spread films; heptanoic acid adsorbed monolayers."
Date: January 1962
Creator: Mann, J. Adiin, Jr. & Hansen, R. S.
Partner: UNT Libraries Government Documents Department

The Solubility of Holmium in Copper, Silver, and Gold

Description: From Abstract: "The solid solubility of holmium in copper, silver, and gold was determined using metallographic techniques. The composition of the first intermetallic compound in these systems was found to be Cu4Ho, Ag7Ho2, and Au3Ho. These compounds form eutectics with the solvent metals which melt at 868, 787, and 778°C respectively."
Date: January 1963
Creator: Wunderlin, W. J.; Beaudry, B. J. & Daane, A. H.
Partner: UNT Libraries Government Documents Department

Acid-Base Reactions and Kinetics of the Halates in Fused Nitrates

Description: From Abstract : "The mechanism of the reactions of the halates, bromate, chlorate, and iodate, with dichromate in fused alkali nitrates has been shown to involve a fast equilibrium followed by a slow rate determining strip to give oxygen and halogen gases as final products." Experiments outlined serve as insight into the structure of fused salts or fused electrolytes.
Date: November 1962
Creator: Schlegel, James Max & Duke, P. R.
Partner: UNT Libraries Government Documents Department

The Effect of Age on the Radiosensitivity of Mice

Description: Abstract: Mice of different ages ranging from 1.5 to 12 months have been exposed to gamma rays in an effort to determine the change in radiosensitivity with age. The dose necessary to cause 50% killing was determined for each age group and sex. No change in sensitivity with age was observed with either sex, although the experimental error in the case of the males was quite large. The females were found to be more resistant than the males.
Date: April 8, 1946
Creator: Curtis, H. J.; Zirkle, Raymond E. (Raymond Elliot), 1902-1988; Anderson, Ernest C., 1920-2013 & Riley, E. F.
Partner: UNT Libraries Government Documents Department

The Equation of State of Solids at Low Temperature

Description: Technical report describing and evaluating the the three experimental methods for obtaining equation of state data at low temperatures; (1) approximate measurement of the PVT relationship by a piston-displacement technique, (2) the measurement of a heat capacity at constant volume as a function of molar volume and temperature, and (3) direct measurement of the pressure variation of the elastic constants using ultrasonic techniques. X-ray methods also might be applicable.
Date: October 13, 1961
Creator: Bernardes, N. (Newton), 1931- & Swenson, C. A.
Partner: UNT Libraries Government Documents Department

Flame Spectra of Vanadium, Niobium, Rhenium, Titanium and Molybdenum

Description: Abstract Line spectra of vanadium, niobium, titanium, molybdenum and rhenium of sufficient intensity to allow detection at the 1–10 p.p.m. level can be excited in fuel-rich, oxy-acetylene flames. For the strongest lines of tungsten, the sensitivity of detection is 90 p.p.m. Weak lines of zirconium, hafnium, osmium, tantalum and uranium are also observed in these flames. Recordings of the spectra are given along with wavelength tables of the strongest lines.
Date: July 23, 1962
Creator: Fassel, Velmer A.; Myers, Robert B. & Kniseley, Richard N.
Partner: UNT Libraries Government Documents Department

Recent Developments in the Physics and Safety of Large Fast Power Reactors

Description: Technical report discussing three principal areas: (1) some recent cross section measurements and their effect on fast reactor calculations; (2) the question of Doppler and sodium void reactivity effects in large fast power reactors and the conflicts inherent in simultaneous optimization of performance, breeding, and safety characteristics; (3) the matter of hybrid fuel cycles.
Date: November 1963
Creator: Okrent, David
Partner: UNT Libraries Government Documents Department

Chlorotriammineplatinum(II) Ion : Acid Hydrolysis and Isotopic Exchange of Chloride Ligand

Description: Abstract: The acid hydrolysis of [Pt(NH3)3Cl] has been shown to occur to a measurable extent. for this reaction: [APt(NH3)cCl]+ + H2O [chemical equilibrium symbol with rate constant k-1 above and k1 below] [Pt(NH3)c(H2O)]++ + Cl-, the equilibrium quotient was measured at 25 degree C and 35 degree C. At 25 degree C this quotient was 8.4 x 10-5 at [Mu] (ionic strength) = 0 and 25 x 10-5 at [mu] = .318 M. This variation is consistent with the expected changes in activity coefficients. [Delta]H for the reaction was found to be approximately 0. The rate constant, k1 was 2.3 x 10-5 sec.-1 at 25 degree C and it was nearly independent of ionic strength. The acid hydrolysis provides a mechanism for the exchange of the chloride ligand and Cl-. Exchange experiments with Cl36 showed that in addition to the acid hydrolysis, a process, first order in both, [Pt(NH3)3Cl] and Cl- with a rate constant of 6. 10-5 sec.-1M.-1 contributes to the exchange. The behavior of the entire series of chloro-ammines of platinum(II) toward acid hydrolysis and chloride exchange has been summarized, and a likely mechanism for the process has been discussed.
Date: May 15, 1961
Creator: Aprile, Ferruccio. & Martin, Don S., Jr.
Partner: UNT Libraries Government Documents Department

Development of Fueled Graphite Containing Pyrolytic-Carbon Coated Carbide Particles for Nonpurged, Gas-Cooled Reactor Systems

Description: Abstract: Progress is reported in several areas of development of fueled graphite containing coated particles for nonurged gas-cooled reactor systems. The sol-gel process has been modified for making spherical particles of both thorium-uranium carbide and thorium-uranium oxide suitable for coating. Equipment has been assembled and methods have been developed for deposition of pyrolytic-carbon coating under well-controlled conditions. Damage to coated particles during fabrication into a graphite matrix depends on the molding pressure and the volumetric content of coated particles. Vendor-supplied coated particles and fueled graphite spheres have been evaluated extensively in both in- and out-of-reactor tests. Duplex- and triplex-coasted particles have excellent fission-gas retention at 2050 degree F to burnups of 15 at. % burnup. Fueled graphite spheres containing coated particles have good irradiation performance, but the fission-gas release rates are somewhat higher than for unsupported coated particles. Fueled graphite spheres react with water vapor about as rapidly as do Speer Mod-2 and ATJ grades of graphite. The diffusion rates in pyrolytic carbon are the same for uranium, thorium, and protactinium. The diffusion rates in the direction parallel to the deposition plane are much higher than those in the perpendicular direction.
Date: November 1963
Creator: Carlsen, F. L., Jr.; Bomar, E. S. & Harms, W. O.
Partner: UNT Libraries Government Documents Department

A Facility for the Production of Pu238

Description: Abstract: A pilot plant facility for recovering Pu238 and unconverted neptunium from irradiated neptunium target elements was operated for 17 months at the Savannah River Laboratory. The process required that the irradiated target elements be dissolved and the solution be processed through three anion exchange cycles for removal of undesirable fission products and cations, recovery of unconverted neptunium, and concentration of Pu238 solution. The process equipment was enclosed in three stainless steel boxes that were installed in two general-purpose cells of a ten-cell complex. The basic cells were not modified. The two cells were not separated from from the adjacent 8 cells. Containment of the high-specific-activity alpha emitters was accomplished by ventilation, development of handling techniques, use of procedures, and close Radiation Control coverage. The facility was dismantled, and the cells were decontaminated and returned to normal use. With the exception of an accidental overexposure, all personnel exposures were kept below the administrative level of 3 R/yr. None of the personnel assimilated detectable amounts of he material handled.
Date: September 1963
Creator: Tetzlaff, R. N.
Partner: UNT Libraries Government Documents Department

Kinetics of the Alkylation and Acylation of Nickel Dipivaloyimethide

Description: Abstract: A study was made of the reactions of nickel dipivaloyimethide with the following reagents: tirphenylmethyl chloride, benzoyl chloride, [rho]-chloro and [rho]-methyl benzoyl chloride. Infrared spectra of the easily hydrolyzed product of tritylation seem to indicate that enol ether, the product of O-alkylation, is formed. the acyl halides reactor to give the triketones. the latter have been characterized by spectra and C, H, analysis. the kinetics of all the reactions studied were found to settle down to a second order rate law after a fast initial reaction. These reactions are catalyzed by an impurity in the acyl chloride. Then benzoyl chloride with a different purity was used, the second order rate constant for the benzoylation of nickel DPM ranged from 0.02-0.20. The air oxidation of nickel dipivaloymethide was found to compete with the acylations under the conditions of these studies. An investigation of the phenomenon showed that nickel pivalate is the major product. Pivalic acid was also detected in the product mixture. This oxidation takes place in chlorobenzene and in aromatic hydrocarbons. It occurs in 1201 when small amount on benzoyl chlorides are present.
Date: July 1959
Creator: Johnson, Kenneth Eugene & Hammond, George Simms, 1921-2005
Partner: UNT Libraries Government Documents Department

Radiation Chemistry of Ammonia Synthesis of Hydrazine

Description: The radiation chemistry of ammonia, pure or with various additives, was studied by Co60 gamma radiation. The kinetics of aniline formation by the irradiation of homogeneous benzene-ammonia mixtures was determined together with the kinetics of hydrazine formation in the case of pure ammonia. The effects of dose, intensity, temperature, and specific additives were determined.
Date: September 23, 1963
Creator: Puig, J. R. & Schwarz, E.
Partner: UNT Libraries Government Documents Department

Beta Radiation Processing at Rigorous Conditions

Description: Introduction: The literature reflects ever expansive studies of radiation chemistry over the past twenty years However, in the application of radiation processing to chemical reactions, in general and excepting a few isolated cases, the yield of useful products have been so low as to preclude practical utilization. Thus, for many reactions,radiation alone at ambient conditions is not a sufficient agent for economical production. Hence, we are led to the investigation of radiation effects on reactions at elevated temperatures and pressures where the thermodynamics favor more extensive reactions that may be induced by radiation. the probability of developing a successful practical radiation process is increased when applying radiation at rigorous conditions. To have a commercial advantage, a radiation process usually must replace an expensive catalyst system, generate a reaction at somewhat less rigorous conditions than is usually employed or yield a better or unique product of high value. In our investigations, we have examined only the potential of radiation as a replacement for contact catalyst. Results: We have worked with coal extract rather than coal because it can be melted or dissolved to facilitate pumping into the processing unit and, in general, permits easier handling than a solid. From numerous radiation runs with coat extract in the liquid phase, treated with 5000 psi of hydrogen pressure, temperatures up to 430 degree C, and total dose of up to 6 megarand, we have disappointingly but conclusively observed red that radiation does not induce hydrogenation beyond that obtain by thermal reaction alone.
Date: November 15, 1963
Creator: Yavorsky, P. M. & Gorin, E.
Partner: UNT Libraries Government Documents Department

The Factors Limiting the Utilization of Zirconium Alloys in Superheated Steam

Description: Abstract: New experimental data and literature data are utilized to determine the upper temperature of usefulness of zirconium alloys. Three basic engineering assumptions are used; (1) service life requirements are on the order of four years; (2) tubular fuel cladding for rod-type fuel is considered with a maximum wall thickness of 1.27 cm; and (3) heat fluxes are above 157 watts/cm. The inter-relation of three basic factors, corrosion rate, corrosion embrittlement by hydrogen and oxygen, and strength are considered. An upper limit for an acceptable corrosion rate for long-term service of 1 mg/dm/day is set primarily by the effect of heat-transfer on corrosion. For the best alloys anticipated, this requirement (even without considering transient conditions) limits cladding surface temperatures to less than 540 degree C. Oxygen embrittlement of the alloy substrate by oxide film dissolution is not expected to be a limiting factor. Corrosion hydrogen embrittlement was studied in detail and found to limit acceptable service to cladding surface temperatures of less than 525 degree C for established experimental alloys. Hydrogen embrittlement may not be a limiting factor if alloys corrosion resistant enough to be acceptable above 600 degree C could be developed. Zirconium alloys designed for high strength to overcome their inherent rapid loss of creep strength at temperatures about 540 degree C are expected to be more susceptible to corrosion hydrogen embrittlement. The results of this study indicate that there is good promise for developing zirconium alloys for fuel cladding application at temperatures to 475 degree C.
Date: November 20, 1963
Creator: Klepfer, H. H. & Douglass, D. L. (David Leslie), 1931-
Partner: UNT Libraries Government Documents Department

Reactivity Worth of Transverse Gaps

Description: Technical report discussing a series a experiments on the reactivity worth of gaps has been performed in the KAPL Solid Homogeneous Assembly (SHA). One objective of the program is to provide data against which calculated models can be checked. An immediate goal is to develop a method by which large void regions can be adequately treated within the framework of diffusion theory. This would enable the nuclear engineer to perform standard design calculations on systems containing such voids. Another objective of the program is to provide data which will allow the shutdown margin of split bed assemblies to be more adequately estimated. for this latter purpose not only the reactivity work of gaps is required by also the rate of change of reactivity with distance as a function of gap size.
Date: November 1963
Creator: Weinstein, S. & Feiner, Frank
Partner: UNT Libraries Government Documents Department

The Uranium-Rhenium Alloy System

Description: Abstract The phase diagram of the uranium-rhenium alloy system is presented along with a discussion on transformation kinetics of the uranium solid solutions. The phase diagram is of the double eutectic type with the intermediate phase having the composition URe2. This phase exhibits allotropy at 180°C and melts congruently at 2200°C. URe2 reacts sluggishly with the uranium solid solutions below 750°C to form the peritectoid compound U2Re. Eutectic reactions occur at 1105° and 2105°C at respective compositions of 10.5 and 65.5 wt. % Re. Eutectoid reactions occur at 643° and 681°C at compositions of 1.4 and 6 wt. % Re, respectively. The maximum solubility of rhenium in α uranium is about 0.4 wt. % at 643°C and in β uranium is 1.9 wt. % at 681°C. The solubility of rhenium in γ uranium is 6 wt. % at 681°C and increases to about 7 wt. % at 975°C. The solubility of uranium in rhenium is 0.6 wt. % at room temperature with little variation up to 2000°C. Alloys of β and γ uranium containing more than about 1.2 and 7 wt. % Re respectively, can be readily supercooled to room temperature. Rapid cooling of γ alloys containing less than about 7 wt. % Re resulted in a direct γ → α′ transformation, the α′ state being a supersaturated α phase having a banded microstructure. Evidence is presented for the existence of two transition states, one involving the γ phase decomposition and the other the β → α transformation. The sequence of phase changes involved in cooling the uranium solid solutions is discussed.
Date: January 14, 1963
Creator: Jackson, R. J. (Robert James), 1929-; Williams, D. E. & Larsen, W. L.
Partner: UNT Libraries Government Documents Department