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Real time analyzer for inverse kinetics rod drop experiments

Description: From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). A system is described that measures subcritical reactivity in nuclear reactors by the Inverse Kinetics Rod Drop (IKRD) technique. The analyzer was used in a large scale reactivity experiment performed in the Fast Flux Test Facility (FFTF) engineering mock-up core loaded in the ZPR-9 at Argonne National Laboratory. The hardware used in the system included (1) a computer operating in a real time environment, (2) an interface to condition the signals from seven neutron sensors located in the reactor core and to transfer them into the computer at fixed time intervals (provisions were made to interface signals from individual neutron detectors operating in either the current or the pulse mode of operation), and (3) a cassette tape recorder for permanent storage of the raw data. The system allows the operator to determine the reactivity condition of the reactor immediately. (auth)
Date: January 1, 1973
Creator: Churchich, M.K.; Mott, J.E.; Robinson, J.C. & Piety, K.R.
Partner: UNT Libraries Government Documents Department

On-line reactor surveillance algorithm based on multivariate analysis of noise

Description: A mini-computer based surveillance algorithm for monitoring signals from nuclear power plants to provide advanced warning of anomalous conditions has been developed and implemented for on-line applications. The reactor state is characterized by the analysis of noise signals. During an observation period when normal conditions prevail, the surveillance algorithm utilizes these noise characterizations to form a statistical description of normal reactor behavior. At the conclusion of this observation period, the surveillance algorithm examines each new incoming characterization to determine if it differs signicantly from the normal description. (auth)
Date: January 1, 1975
Creator: Piety, K.R. & Robinson, J.C.
Partner: UNT Libraries Government Documents Department

Spectroscopic and electrochemical studies of selected lanthanides and actinides in concentrated aqueous carbonate and carbonate-hydroxide solutions and in molten dimethyl sulfone

Description: Electrochemical and spectroscopic studies of neptunium, plutonium, americium, californium, and terbium in concentrated aqueous carbonate and carbonate-hydroxide solutions have been carried out. Changes in the absorption spectra of Np(VII), Np(V), Pu(VI), Pu(V), Am(VI), and Am(V) in concentrated Na/sub 2/CO/sub 3/ solution and in the formal potentials of the Np(VI)/Np(V) and Pu(VI)/Pu(V) couples as a function of pH were observed. Heptavalent neptunium in concentrated Na/sub 2/CO/sub 3/ solution could only be producted at pH values close to or greater than 14. Plutonium(VII) in 2 M Na/sub 2/CO/sub 3/ solution could only be produced at hydroxide ion concentrations in excess of about 2.5 M. The complexation of Np(VII) and Pu(VII) in Na/sub 2/CO/sub 3/-NaOH solution seems to be mainly by hydroxide ions. Neptunium(IV) and plutonium(IV) are insoluble in Na/sub 2/CO/sub 3/ solution above ca. pH 11-12. Neptunium(III) in carbonate solution is rapidly oxidized by water to Np(IV). Plutonium(III) is insoluble in Na/sub 2/CO/sub 3/ solution. In K/sub 2/CO/sub 3/ solution Pu(III) is stable to oxidation by water but is very sensitive to air oxidation. The redox properties of Cf(III) in Na/sub 2/CO/sub 3/ and K/sub 2/CO/sub 3/ solutions at pH values from 8 to 14 were investigated. The oxidation of terbium(III) in K/sub 2/CO/sub 3/-KOH solution was studied. Spectroscopic and electrochemical studies of cerium, samarium, europium, ytterbium, uranium, neptunium, plutonium, and americium in molten dimethyl sulfone (DMSO/sub 2/) at 400 K were performed. Differences in the DMSO/sub 2/ solution absorption spectra of trivalent Sm, Eu, and Yb and divalent Eu compared with those in aqueous solution were observed. Complexation effects on the spectra of Ce(III), Ce(IV), U(VI), Np(VI), Pu(VI), and Am(VI) are more noticeable in poorly coordinating DMSO/sub 2/ than they are in water. 123 references, 54 figures, 11 tables.
Date: March 1, 1985
Creator: Varlashkin, P.G.
Partner: UNT Libraries Government Documents Department

In situ conversion of coal. Final report, June 1, 1975--November 30, 1977. [Tulupov, muetherties and other catalysts]

Description: One of the factors which encouraged us to search for very mild liquefaction conditions was the reported existence of a variety of catalysts capable of causing the hydrogenation of aromatics at room temperature or slightly above and at hydrogen pressures of one or two atm. A number of such systems are described in James book. (Homogeneous Hydrogentation by B. R. James). Each promising system was tested with coal; nothing worked. Intermolecular hydride transfer from a variety of compounds to carbonium ions is a well known, well studied reaction and has been reviewed. The reaction developed uses BF/sub 3/.H/sub 2/O as the acid and Et/sub 3/SiH as the hydride donor. The organic compound to be reduced is protonated by the BF/sub 3/.H/sub 2/O to give a carbonium ion which then hydride abstracts from the Et/sub 3/SiH. Thus, half of the hydrogen introduced comes from water and the other half from the hydride donor. Two features of this reaction exist. One, it is a very mild reduction of aromatics which should find synthetic utility. Second, some sulfur is removed from coals under very mild conditions together with some conversion of bituminous coals.
Date: October 1, 1977
Creator: Larsen, J.W.
Partner: UNT Libraries Government Documents Department

Shape memory effect in uranium-niobium alloys below room temperature. Final report. [6. 2 to 7. 0 wt % Nb]

Description: The temperature dependence of the martensitic ..gamma../sup 0/ to ..cap alpha../sup 11/ phase transformation between 25/sup 0/C and -198/sup 0/C in water-quenched uranium-niobium alloys between 6.2 and 7.0 wt % niobium was determined using cold-stage x-ray diffraction experiments. Lowering the temperature promoted the transformation to ..cap alpha../sup 11/ but complete transformation was never observed. The transformation was reversible with little or no hysteresis. Aging the alloys for two hours at 200/sup 0/C stabilized the ..gamma../sup 0/ phase and retarded the martensitic transformation. The compositions where M/sub s/ and M/sub f/ equaled room temperature were 5.80 and 7.04 wt % Nb respectively. At -196/sup 0/C these values were approximately 0.25 wt % higher. Two alloys were selected as potential candidates for a uranium alloy clamp.
Date: March 1, 1985
Creator: Vandermeer, R.A.
Partner: UNT Libraries Government Documents Department

Stochastic model to monitor mechanical vibrations in pressurized water reactors

Description: The feasibility of using neutron flux and core-exit temperature signals in PWRs for estimating core coolant flow velocity has been demonstrated using normal operational data from both the LOFT reactor and a commerical PWR. The LOFT analysis further showed that the core coolant velocity can be accurately monitored for various flow rates using the linear phase-frequency relationship in the frequency range 0.1 to 2 Hz. The development of the technique for monitoring core coolant velocity in PWRs provides a valuable alternative for flow measurement. Theoretical studies of core heat transfer in PWRs showed that the fluctuating heat sources have a dominating effect on the core-exit temperature compared to fluctuations of the coolant flow rate and core inlet coolant temperature. In the present analysis a detailed distributed parameter model of a PWR core was developed with the purpose of studying the following aspects of core coolant flow rate measurement: the mechanisms causing linear phase relationship between neutron flux and coolant temperature signals due to various perturbation sources; the effect of axial flux shape on the phase slope (or estimated transit delay time); and the relationship between transit delay time and effective distance of temperature noise propagation to maintain the flow velocity invariant.
Date: January 1, 1984
Creator: Shieh, D.J. & Upadhyaya, B.R.
Partner: UNT Libraries Government Documents Department

Charmed meson lifetimes from 20 GeV photoproduction

Description: A sample of 134 events containing 159 visible multiprong charm decays has been obtained from the 20 GeV charm photoproduction experiment at the SLAC Hybrid Facility. Following a selection procedure which ensures high and uniform detection efficiency for selected events, 47 charged, 46 neutral and five topologically ambiguous decays remain. These decays yield preliminary lifetimes of ..pi../sub D/sup +-// = (9.2 +- 1.5 +- 0.5) x 10/sup -13/ secs ..pi../sub D//sup 0/ approx. = (6.1 +- 1.1 +- 0.4) x 10/sup -13/ secs and a ratio (phi/sub D/sup +-//)/(tau/sub D/sup 0//) = 1.5/sub -0.3//sup +0.6/ +- 0.1. One fully reconstructed four-body D/sup 0/ decay has a proper flight time of 55 x 10/sup -13/ seconds. 5 refs., 4 figs.
Date: January 1, 1985
Creator: Brau, J.E.
Partner: UNT Libraries Government Documents Department

Dynamics of the recovery of damaged tundra vegetation: preliminary results of revegetation experiments of maritime tundra with Elymus mollis on Adak Island, Alaska. Progress report

Description: The vegetation of the central Aleutian Islands, Alaska is maritime tundra (Amundsen, 1977). While maritime tundra is not characterized by the presence of permafrost, the soil temperatures remain low (5 to 7/sup 0/C) year-round (Williams, 1980). The low soil temperature, a high level of soil moisture, and a low level of incident solar radiation are thought to delay the development of the vegetation. Natural revegetation of natural or man made open areas is relatively slow. Disturbed areas from World War II military activity are not completely revegetated after almost 40 years. Because of the windy and wet climate of the region, exposed soil is unstable and subject to extensive freeze-thaw action and erosion. Insults to the vegetation, both marine and aeolian, are common. Successful reproduction by seed is uncommon among species of this flora. The primary means of reproduction appears to be by vegetative propagules which are usually fragments of the shoot and rhizome. While the transport of the fragments by wind and water aids in the dispersal of the propagules, the same action often removes these fragments from open areas. This later activity further delays the revegetation of open and disturbed areas. Elymus mollis Trin. is the most successful major native species found to date as it fragments due to wind and water action and transplants easily. Transplanting experiments with sprigs of Elymus mollis Trin. have been conducted on Adak Island, Alaska since 1977. Preliminary results indicate that Elymus mollis may be transplanted for revegetation with a survival rate of at least 90 percent. Experiments were set up in 1979 to determine appropriate planting density, sprig rhizome length, and best time of year for transplanting. Preliminary results for these experiments are reported here.
Date: August 1, 1982
Creator: Amundsen, C C & McCord, R A
Partner: UNT Libraries Government Documents Department

Detection of single atoms by resonance ionization spectroscopy

Description: Rutherford's idea for counting individual atoms can, in principle, be implemented for nearly any type of atom, whether stable or radioactive, by using methods of resonance ionization. With the RIS technique, a laser is tuned to a wavelength which will promote a valence electron in a Z-selected atom to an excited level. Additional resonance or nonresonance photoabsorption steps are used to achieve nearly 100% ionization efficiencies. Hence, the RIS process can be saturated for the Z-selected atoms; and since detectors are available for counting either single electrons or positive ions, one-atom detection is possible. Some examples are given of one-atom detection, including that of the noble gases, in order to show complementarity with AMS methods. For instance, the detection of /sup 81/Kr using RIS has interesting applications for solar neutrino research, ice-cap dating, and groundwater dating. 39 refs., 7 figs., 2 tabs.
Date: January 1, 1986
Creator: Hurst, G.S.
Partner: UNT Libraries Government Documents Department

Analytical evaluations of the endochronic nonlinear concrete model. [PCRV development; HTGR base technology]

Description: Comparison of the results of finite element (FEM) analyses were made with actual test data on prestressed concrete beam models. The ADINA computer program was used to perform the analyses with two material models for concrete. One material model was the concrete model furnished with ADINA and the second was the endochronic model as added by D.N. Fanning at Oak Ridge. Results of the prestressed concrete beam tests were compared to ADINA FEM results for both the regular and the endochronic material models. Published results of concrete specimens tested in uniaxial, biaxial, and triaxial states of stresses were collected and reduced to computer data files. The data files were then used to compare with results predicted by the endochronic theory in another computer program. The results of these comparisons, the source of the reference material, and a plot of the comparisons are included. A total of thirty two files were created in this phase of the study.
Date: unknown
Creator: Goodpasture, D.W. & Burdette, E.G.
Partner: UNT Libraries Government Documents Department

Handbook for preservation of local railroad service. Final report

Description: Throughout the United States, there is an accelerating abandonment of redundant and/or unprofitable light-density railroad lines. This abandonment can be economically harmful to both the shippers and the communities that were previously served. Although greater dependence upon truck transportation is a viable alternative in many cases, other situations indicate that the greatest priority should be attached to preserving some form of local railroad service. The objective of this research was to develop a handbook to assist shippers, local and state governments, and rail planners when their Class I rail service is scheduled for abandonment. Two major options are detailed in the handbook. The first regards innovative procedures which may be used by local groups in attempting to preserve service by the existing Class I carrier. The second approach considers the alternative of operating the particular line as an independent railroad.
Date: January 1, 1977
Creator: Patton, E.P. & Langley, C.J. Jr.
Partner: UNT Libraries Government Documents Department

Parton distributions in nuclei: Quagma or quagmire

Description: The emerging information on the way quark, antiquark, and gluon distributions are modified in nuclei relative to free nucleons is reviewed. Particular emphasis is placed on Drell-Yan and /psi/ production on nuclei and caution against premature use of these as signals for quagma in heavy-ion collisions. If we are to identify the formation of quark-gluon plasma in heavy-ion collisions by changes in the production rates for /psi/ relative to Drell-Yan lepton pairs, then it is important that we first understand the ''intrinsic'' changes in parton distributions in nuclei relative to free nucleons. So, emerging knowledge on how quark, antiquark, and gluon distributions are modified in nuclei relative to free nucleons is reviewed, and the emerging theoretical concensus is briefly summarized.
Date: January 1, 1988
Creator: Close, F.E.
Partner: UNT Libraries Government Documents Department

Support for a nuclear future: student response to the CRBRP

Description: Results are presented of a multiple regression analysis of questionnaire data from two random samples of University of Tennessee seniors. Data were collected from 94 students with science/engineering majors (the ''Tech'' sample), and 91 students with non-science/engineering majors (the ''Mass'' sample--which represents the majority of the students). The purpose of the analysis was to isolate factors which independently explain student response to the CRBRP and to breeder reactors in general.
Date: January 1, 1977
Creator: Bremseth, M.D. & Clelland, D.A.
Partner: UNT Libraries Government Documents Department

Deploymerization of coal by direct solvent attack. Semi-annual report, April 1, 1983-August 31, 1983

Description: The depolymerization of Illinois No. 6 coal by a series of solvents having different basecities (pK/sub a/) and nucleophilicities (Swain-Scott nu values) showed no dependence on either the basicity of nucleophilicity of the solvents. As expected, the conversion decreases as the temperature of the reaction is reduced, but the lower the reaction temperature, the higher the percentage of amine incorporation becomes in the products. 5 tables.
Date: September 15, 1983
Creator: Larsen, J.W. & Mohammadi, M.
Partner: UNT Libraries Government Documents Department

Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980

Description: Areas covered are: optical and dielectric properties of hexamethyl-phosphoric triamide; photoemission from uv irradiated liquids; photon and photoelectron mean free paths in liquids; properties of Kapton films; and uv transmission of polycyclic organic molecules. (GHT)
Date: January 1, 1980
Creator: Painter, L.R.
Partner: UNT Libraries Government Documents Department

Magnetic measurements of the transuranium elements. Progress report, January 1-December 31, 1986

Description: Magnetic measurements have been made on polycrystalline CfCl/sub 3/ in both a hexagonal and orthorhombic crystal form. The magnetic properties were studied as a function of crystal structure by converting the same sample back and forth from one form to the other. In a continuation of a study of the magnetic transition temperature as a function of actinide-actinide separation of the curium pnictide series we have undertaken magnetic measurements on curium bismuthide during this contract period. We have accomplished several milestones in our program to grow single crystals of actinide metals and compounds and determine their solid-state properties. Previous physical property measurements on transamericium actinide materials have been mainly limited to polycrystalline samples due to the limited availability of materials and the great material losses incurred during the common crystal growth methods. We have investigated a low-loss, microscale technique of crystal growth using lanthanides as non-radioactive stand-ins for the radioactive actinides.
Date: September 1, 1986
Creator: Nave, S.E.
Partner: UNT Libraries Government Documents Department

Research in radiation monitoring survey instrumentation. Final report

Description: Two low-power solid-state prototype readout units were developed, an LED display and a LCD display. This display output was in a bar-graph format, covering four-decades of information, with 10-segments per decade. The displays accept a frequency input, which is standardly available from several portable radiation-survey instruments. Both readout units will operate on two D-cell batteries (3.0 Volt), with a typical current drain requirement of 0.3 MA for the LED display and 30..mu..A for the LCD display. A wide-range electrometer circuit was also developed. The circuit covers an input current range from 10/sup -13/ A to 10/sup -8/ A. The output signal is a pulse whose frequency is directly proportional to input current. The circuit requires no high-megohm resistors, and is autoranging. Several candidate input amplifiers were analyzed and evaluated for use with the electrometer circuit.
Date: January 20, 1978
Creator: Blalock, T.V.; Kennedy, E.J.; Phillips, R.G. & Walker, E.W. Jr.
Partner: UNT Libraries Government Documents Department

Reactivity of fly ashes in a spray dryer FGD process

Description: During the period 1981-1982, a study was performed to determine the ability of various fly ashes to retain sulfur dioxide in a pilot plant spray dryer/fabric filter flue gas desulfurization system. This knowledge would provide design engineers with the necessary data to determine whether the fly ash from a particular utility could be used as an effective supplement or substitute for slaked lime in a spray dryer system. The study commenced with the collection of 22 fly ashes from lignite, subbituminous, and bituminous eastern and western coals. The ashes were contacted with the flue gas entering the pilot plant by two different techniques. In the first, the ashes were slurried in water and injected into the spray dryer through a spinning disk atomizer. In the second, the ashes were injected as a dry additive into the flue gas upstream of the spray dryer. Analyses were conducted to determine the ability of each ash to retain sulfur dioxide in the system followed by statistical correlations of the sulfur retention with the physical/chemical properties of each ash. 17 references, 32 figures, 19 tables.
Date: May 1, 1983
Creator: Davis, W.T. & Reed, G.D.
Partner: UNT Libraries Government Documents Department

Research in remote signal transmission electronics

Description: Research has been directed toward the evaluation of semiconductor circuits suitable for operation at temperatures of 250/sup 0/C to 300/sup 0/C. These circuits are to be utilized in monitoring neutron flux in a breeder reactor. Worst-case performance evaluations are made on an amplifier-discriminator circuit utilizing commercially available operational amplifier chips incorporated in a hybrid thick-film package, which is suitable for use to 250/sup 0/C. Another hybrid thick-film amplifier-discriminator system was developed and tested for use to 300/sup 0/C. A dc-dc converter to supply +10v and -10v for amplifier power was designed, and evaluated up to an operating temperature of 300/sup 0/C. Detailed design theory equations for high temperature dc-dc converters are presented. Significant problems with ceramic capacitors utilized at 300/sup 0/C were found.
Date: October 1, 1979
Creator: Kennedy, E.J.; Blalock, T.V.; Phelps, J.; Rochelle, R. & Dyer, F.
Partner: UNT Libraries Government Documents Department

Research in remote signal transmission electronics. Report II

Description: Research has been directed toward the evaluation of semiconductor circuits suitable for operation at temperatures of 230/sup 0/C. These circuits are to be utilized in monitoring neutron flux for initial fuel loading in a breeder reactor. Two new amplifier circuits were developed and tested, as well as new concepts for a high current driver circuit and a temperature-stable discriminator-multivibrator circuit. An improved dc-dc converter circuit was constructed and evaluated at 230/sup 0/C. Initial data were obtained on radiation effects on discrete devices, integrated circuits, resistors, and capacitors, for possible use in fuel reloading requirements.
Date: October 1, 1980
Creator: Kennedy, E.J.; Blalock, T.V.; Genther, S.; Mukund, P. & Orrick, H.
Partner: UNT Libraries Government Documents Department

Failure of single electron descriptions of molecular orbital collision processes. [Electron promotion mechanism]

Description: Inner-shell excitation occurring in low and moderate (keV range) energy collisions between light atomic and ionic systems is frequently describable in terms of molecular promotion mechanisms, which were extensively explored both theoretically and experimentally. The bulk of such studies have concentrated on processes understandable through the use of single- and independent-electron models. Nonetheless, it is possible to find cases of inner-shell excitation in relatively simple collision systems which involve nearly simultaneous multiple-electron transitions and transitions induced by inherently two-electron interactions. Evidence for these many- and nonindependent-electron phenomena in inner-shell excitation processes and the importance of considering such effects in the interpretation of collisionally induced excitation spectra is discussed. 13 references.
Date: January 1, 1978
Creator: Elston, S.B.
Partner: UNT Libraries Government Documents Department

Analysis of relationship between stability and flow parameters in a BWR

Description: Results of quantitative analysis of mutual relationship between the BWR stability and channel steam velocity are presented. The stability parameter, defined by the damping ratio, and the steam velocity are estimated by analysis of neutron noise data from local power range monitor (LPRM) detector signals. These parameters are treated as varying randomly as a function of time.
Date: January 1, 1980
Creator: Upadhyaya, B.R. & Kitamura, M.
Partner: UNT Libraries Government Documents Department