Aerodynamic Re-Entry Analysis. Task 2. Thermoelectric Generator Summary Report (open access)

Aerodynamic Re-Entry Analysis. Task 2. Thermoelectric Generator Summary Report

An analytical trajectory and aerothermodynamic analysis of a satellite containing a Task 2 thermoelectric generator was completed. A 300-statute mile circular polar orbit was used for this analysis and the launch was assumed to be from Vandenberg Air Force Base. Results of this study show that upon natural decay from a successful mission, the radio-cerium fuel will burn up in space at high altitude, thus only a very minor amount of radio cerium will be released to the stratosphere. A complete analyses of the fate of the radio-cerium fuel following various aborted launching attempts also was carried out. Charts summarizing the various assumed failures and locations of the fuel following failure are shown. A technical discussion of the methods used in performing the analysis is included in the report. (auth)
Date: December 27, 1960
Creator: Oehrli, R.
Object Type: Report
System: The UNT Digital Library
Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: January--March 1978 (open access)

Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: January--March 1978

The exposure of noncellulosic ultrafiltration membranes to a radioactive environment simulating up to 24 months of exposure to a beta dose of 10 ..mu..Ci/cm/sup 3/ and a gamma dose of 10/sup -5/ ..mu..Ci/cm/sup 3/ did not show any conclusive evidence of membrane degradation. Viscosity measurements for control membranes and irradiated membranes indicate no changes in polymer molecular weight were caused by the radiation exposure. This, in turn, suggests no physical or mechanical degradation took place. A continuous run on the ultrafiltration pilot plant was completed. The run lasted 33.5 hr; during this period, the flux declined from 4 gal/min to 0.8 gal/min while rejection of alpha activity increased slightly. A total of 20,000 gal were processed through the ultrafiltration system. The small laboratory column tests were continued with uranium-233 and americium-241. Several new resins were being evaluated along with the same type of resin as used before with uranium-233 and plutonium-238. Tests were continued with the 2-in. Engineering Columns using ultrafiltration product spiked with uranium-233.
Date: April 27, 1978
Creator: Koenst, J. W.; Herald, W. R. & Roberts, R. C.
Object Type: Report
System: The UNT Digital Library
Fundamental Studies of Erosion for Coal Gasification Systems. Annual Progress Report, 1 November 1979-30 June 1980 (open access)

Fundamental Studies of Erosion for Coal Gasification Systems. Annual Progress Report, 1 November 1979-30 June 1980

The effort in this program is divided between modelling the particle impact event using numerical methods and computer calculations and actual measurement of erosion rates. While the results obtained from each of these activities must be combined to provide an improved understanding of particulate erosion of ductile materials, it is convenient to describe separately the progress in each activity area. The first step in the application of the finite element method to any problem is the dissolution of the continuum into small elements. The intent of this procedure is to use as few total elements as possible and to make the elements small where gradients are large and vice versa. The exact solution for the contact of a rigid cylinder with an elastic surface is available from Hertz. This solution has been compared with the computer results obtained from finite element maps containing 148, 273, and 474 elements. The correlation between the computer results and elastic solution is not good for the map with the fewest elements, but improves as the number of elements increases. Convergence to this exact solution has been examined as a function of the number of map elements as a means of improving the efficiency of …
Date: July 27, 1980
Creator: Follansbee, P. S.; Sinclair, G. B. & Williams, J. C.
Object Type: Report
System: The UNT Digital Library
EGCR EXPERIMENTAL LOOPS, PRELIMINARY DESIGN REPORT (open access)

EGCR EXPERIMENTAL LOOPS, PRELIMINARY DESIGN REPORT

The EGCR was designed to accommodate up to four gascooled experimental loops plus several experimental fuel elements in the open core. Two of the loops will utilize 51/2-in.-O.D. stainless steel tubes passing through the core along an axis which is about 17 in. from the central axis of the core. The other two loops will utilize 91/2-in.-o.d. tubes about 68 in. from the central axis. Inherent safety in the design, facility design, primary loop design, auxiliary systems and equipment design, primary and secondary containment design, instrumentation and controls, and special operations are discussed. (M.C.G.)
Date: March 27, 1962
Creator: Neill, F.H. & Michelson, C.
Object Type: Report
System: The UNT Digital Library
Two dimensional NMR and NMR relaxation studies of coal structure (open access)

Two dimensional NMR and NMR relaxation studies of coal structure

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed a delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.
Date: May 27, 1992
Creator: Zilm, K.W.
Object Type: Report
System: The UNT Digital Library
Theoretical and experimental studies of churn flow in vertical tubes. Final technical report (open access)

Theoretical and experimental studies of churn flow in vertical tubes. Final technical report

The pattern known as churn flow is a highly unsteady pattern with stochastic features and is extremely complex. However, calculations show that for many geothermal wells the condition of churn flow consists over much of the length of the two phase zone. Furthermore, it frequently exists at the surface so that design of separation equipment and surface piping depends on the accurate modelling of this type of flow. It has been the long term purpose of this project to develop physically based models for churn flow which can be used as a basis for predicting holdup, frictional loss and heat transfer rates for this flow pattern in geothermal systems. To achieve this end, it was necessary to develop new methods for measuring the time dependent characteristics of the flow and thus be able to uncover the basic physics of the flow. Models can then be developed based on this understanding which characterizes the flow and equations for holdup, friction and heat transfer evolved.
Date: January 27, 1986
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980 (open access)

Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980

The overall objective of this contract is to assist in the development of fuel-flexible combustion systems for gas turbines as well as Rankine and Stirling cycle engines. The primary emphasis of the program is on liquid hydrocarbons produced from non-petroleum resources. Fuel-flexible combustion systems will provide for more rapid transition of these alternative fuels into important future energy utilization centers (especially utility power generation with the combined cycle gas turbine). The specific technical objectives of the program are: (a) develop an improved understanding of relationships between alternative fuel properties and continuous combustion system effects, and (b) provide analytical modeling/correlation capabilities to be used as design aids for development of fuel-tolerant combustion systems. This is the second major report of the program. Key experimental findings during this reporting period concern stirred combustor soot production during operation at controlled temperature conditions, soot production as a function of combustor residence time, an improved measurement technique for total hydrocarbons and initial stirred combustor results of fuel nitrogen conversion. While the results to be presented concern a stirred combustor which utilizes premixed fuel vapor/oxidant mixtures, a new combustor which combusts liquid fuel injected into the reactor as a spray has been developed and will be …
Date: February 27, 1980
Creator: Blazowski, W.S.; Edelman, R.B. & Wong, E.
Object Type: Report
System: The UNT Digital Library
Single Element Flow Tests for Type 3 (SM-2) Fuel Elements in SM-1, SM-1A, and PM-2A Cores (open access)

Single Element Flow Tests for Type 3 (SM-2) Fuel Elements in SM-1, SM-1A, and PM-2A Cores

Channel-to-channel flow distribution within Type 3 (SM-2, stationary and control rod fuel elements modified for use in the SM-1, SM1-1A, and PM-2A core support structures and control rod tubes was measured in single element flow testing. Plots of channel-to-channel flow distribution and element pressure drop at various element flow rates are given. Flow distribution for the top-orificed SM-1A and PM-2A stationary elements was within the plus or minus 12% deviation from element average utilized in previous thermal analyses of these cores. Testing of the bottom-orificed SM-1 stationary element and the SM-1, SM-1A, and PM-2A control rod assemblies showed flow distribution exceeded plus or minus 12% devation from average. Simple modifications to the SM-1 stationary element indicated the possibility of improvng fiow distribution in that element. (auth)
Date: November 27, 1961
Creator: Krause, P. S.
Object Type: Report
System: The UNT Digital Library
Model for H/sup -/ and D/sup -/ production by hydrogen backscattering (open access)

Model for H/sup -/ and D/sup -/ production by hydrogen backscattering

The Marlowe Monte-Carlo backscattering code has been used to calculate particle reflection coefficients and energy distributions for H, D incident upon Li, K, Ni, Cu, Mo, Ag, Cs, Hf, W, Pt, and U surfaces. The backscattered energy and angular distributions are combined with a model for formation and survival probabilities for H/sup -/, D/sup -/ leaving the surface. A least-squares fit of experimental measurements of H/sup -/ yields from the composite surface, Cs/Cu, has been used to obtain two semi-empirical constants, ..cap alpha.., ..beta.. which enter into the formation and survival probabilities. These probabilities are used to calculate the production probability which in turn provides an upper limit to the negative ion yield. The choice of electrode material is discussed as a function of atomic number.
Date: May 27, 1980
Creator: Hiskes, J.R. & Schneider, P.J.
Object Type: Report
System: The UNT Digital Library
Thermal Stress Testing of Type 1 Fuel Plates (open access)

Thermal Stress Testing of Type 1 Fuel Plates

Thermal stress tests on Type 1, SM-1A Core II fuel ele-ment sections were performed to study plate distortion and determine its dependency on temperature distribution, temperature differential, initial flatness, and ripple length. Test results will be correlated with the analytical model and used to predict ripple growth in other plate-type fuel elements. The tests showed that ripple growth is dependent on initial flatness of the plate and that the characteristic shape of ripples is maintained at all temperature differentials: The tests also showed that the ripple growth rate for a ripple of 5 mil initial magnitude is approximately 0.12 mils/ deg F for a peak temperature differential of 103 deg F and that the apparent relationship between ripple net growth and length is 1.3 mil/in. of ripple for a peak temperature differential of 103 deg F. A permanent distortion of 2 mils for a complete temperature cycle from 0 to 103 to O deg F differential was found. The temperature profile across the plate width was found to affect the magnitude of ripple growth. (auth)
Date: June 27, 1962
Creator: Gebhardt, F. G.
Object Type: Report
System: The UNT Digital Library
Preliminary designs for ocean thermal energy conversion (OTEC) stationkeeping subsystems (SKSS). Task II. Conceptual design. Final report (open access)

Preliminary designs for ocean thermal energy conversion (OTEC) stationkeeping subsystems (SKSS). Task II. Conceptual design. Final report

The study is presented in five sections: design loads, conceptual designs, trade studies, cost analysis and concept evaluation and ranking. Extensive appendixes provide back up calculations and data to support the results. Environmental forces and yaw moments acting on the barge and spar in the various design sea states are presented including wave, wind and current effects. A parametric analysis illustrates the impact on holding power requirement of varying the return periods for operational and extreme sea state. The conceptual designs are presented for the barge followed by those for the spar, including configuration definition, performance characteristics, interfaces, areas for development, and deployment scenarios for selected concepts. The concept definition is followed by a set of trade studies that were performed to evaluate candidate anchor types and anchor leg materials. Parametric variations in anchor leg characteristics, wire-rope-to-chain length ratio for example, illustrate the influence of the significant design parameters on performance. An extensive cost analysis of the candidate SKSS concepts is presented, including cost estimates, life cycle cost scenarios leading to expected value of life cycle cost, and cost equivalence of operational failures. An evaluation of the eight SKSS concepts is presented, including assessment of performance and rankings based on …
Date: July 27, 1979
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results (open access)

Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results

Results are presented of comparative timing tests made by running a typical FORTRAN physics simulation code on the following machines: DEC PDP-10 with KI processor; DEC PDP-10, KI processor, and FPS AP-190L; CDC 7600; and CRAY-1. Factors such as DMA overhead, code size for the AP-190L, and the relative utilization of floating point functional units for the different machines are discussed. 1 table.
Date: March 27, 1980
Creator: Brengle, T.A. & Maron, N.
Object Type: Article
System: The UNT Digital Library
Magnetic shielding design analysis (open access)

Magnetic shielding design analysis

Two passive magnetic-shielding-design approaches for static external fields are reviewed. The first approach uses the shielding solutions for spheres and cylinders while the second approach requires solving Maxwell's equations. Experimental data taken at LLNL are compared with the results from these shieldings-design methods, and improvements are recommended for the second method. Design considerations are discussed here along with the importance of material gaps in the shield.
Date: December 27, 1983
Creator: Kerns, J.A.; LaPaz, A.D. & Fabyan, J.
Object Type: Article
System: The UNT Digital Library
The excess flux in the cosmic submillimeter background radiation and the primordial deuterium abundance (open access)

The excess flux in the cosmic submillimeter background radiation and the primordial deuterium abundance

Recent measurements of the cosmic background radiation (CBR) show an enhanced flux in the submillimeter regime, compared to the spectrum of a 2.7 K blackbody. Thermal Comptonization of the relic radiation by a hot nonrelativistic plasma has long been known to produce distortions in the CBR spectrum, similar to what has now been observed. Heating of the primeval plasma to temperatures T {approximately} 10{sup 6} {minus} 10{sup 8} K could result from the injection of subcosmic ray protons at epoch z {approximately} 10--100. The intensity of the subcosmic ray flux that provide conditions needed to explain the submillimeter excess by thermal Comptonization also leads to the production of cosmologically significant amounts of deuterium in collisions between subcosmic ray protons and primordial protons and {alpha}-particles. However, the amount of lithium produced through {alpha}-{alpha} reactions is in conflict with the observed Li abundance. If lithium is depleted, for example, by processing through Population II stars, arguments for the baryon content of the universe based on primordial deuterium and He abundances are weakened. 12 refs., 1 fig., 1 tab.
Date: October 27, 1989
Creator: Dermer, C. D.; Guessoum, N. (Lawrence Livermore National Lab., CA (USA) & National Aeronautics and Space Administration, Greenbelt, MD (USA). Lab. for High Energy Astrophysics)
Object Type: Article
System: The UNT Digital Library
Nuclear Analysis of Various Spert-III Critical Experiments (open access)

Nuclear Analysis of Various Spert-III Critical Experiments

Editor please delete 26456.<><DSN>16:026457<ABS>Work done in the P122 reactor control actuator area is summarized. Actuators were required to radially position the absorber blades in the core of the reactor. The P122C1 was a subsonic power plant and temperatures were low enough to permit the use of hydraulics in the actuator area. The program was reoriented and the power plant designated P122C3 which was a supersonic version of the folded flow power plant. The ambient temperature at maximum power was high enough to require pneumatic actuation of the control blades. The program was reoriented after two design iterations of the subsonic power plant. A test model of the actuating equipment and the entire linkage assembly was on hand and completed when the program was cancelled. The linkage was being redesigned for the supersonic application and special bearings were ordered for fabrication into the lower temperature rig. The actual mechanical concepts of the pneumatic actuator were under study when the program was cancelled. (auth)
Date: April 27, 1961
Creator: Paluszkiewicz, S.
Object Type: Report
System: The UNT Digital Library
Diffusion welding multifilament superconductive composites (open access)

Diffusion welding multifilament superconductive composites

Diffusion welding is shown to be a feasible method for joining composites of niobium-titanium superconductor alloy filaments in a pure copper matrix. Good results were repeatedly obtained using 15/sup 0/ scarf joints welded with externally heated tooling and simple uniaxial compression loading in a conventional hydraulic press. Weld cycles of less than one hour total elapsed time were readily attainable. Through proper closed-die design, it was possible to increase welding pressure sufficiently to use relatively low temperatures to coincide with the optimum aging heat treatment of the superconductor alloy. This temperature limitation is important to retain optimal superconductor properties. Confirming measurements of critical current density of welded joints at 4.2/sup 0/K are in progress. In the welded joints made under optimum conditions, there is bonding of all constituents, including superconductor filaments. Weld tooling which effectively contains the relatively fluid matrix, and resists deformation during repeated weld cycles, is essential to the successful application of the diffusion welding process to these composites.
Date: February 27, 1978
Creator: Witherell, C.E.
Object Type: Article
System: The UNT Digital Library
Seismic risk analysis for General Electric Plutonium Facility, Pleasanton, California. Final report, part II (open access)

Seismic risk analysis for General Electric Plutonium Facility, Pleasanton, California. Final report, part II

This report is the second of a two part study addressing the seismic risk or hazard of the special nuclear materials (SNM) facility of the General Electric Vallecitos Nuclear Center at Pleasanton, California. The Part I companion to this report, dated July 31, 1978, presented the seismic hazard at the site that resulted from exposure to earthquakes on the Calaveras, Hayward, San Andreas and, additionally, from smaller unassociated earthquakes that could not be attributed to these specific faults. However, while this study was in progress, certain additional geologic information became available that could be interpreted in terms of the existance of a nearby fault. Although substantial geologic investigations were subsequently deployed, the existance of this postulated fault, called the Verona Fault, remained very controversial. The purpose of the Part II study was to assume the existance of such a capable fault and, under this assumption, to examine the loads that the fault could impose on the SNM facility. This report first reviews the geologic setting with a focus on specifying sufficient geologic parameters to characterize the postulated fault. The report next presents the methodology used to calculate the vibratory ground motion hazard. Because of the complexity of the fault geometry, …
Date: June 27, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
AN ESTIMATE OF THE EFFECT OF NEUTRON-ENERGY SPECTRUM ON RADIATION DAMAGE OF STEEL (open access)

AN ESTIMATE OF THE EFFECT OF NEUTRON-ENERGY SPECTRUM ON RADIATION DAMAGE OF STEEL

The postulate that the average number of lattice displacements is directly proportional to the available energy is carried one step further; it is assumed that damage to steel (particularly in regard to brittle fracture) is proportional to the number of lattice vacancies that occur. The model, although crude, permits estimation of the relative damage resulting from differences in neutron spectra. The results can be used as a rough method of correcting damage data for the effect of the neutron-energy spectrum. Radiation damage calculations for steel, relative to those for a fission spectrum, were made for neutron spectra that result from fission neutrons penetrating water or graphite. The results were plotted as a function of effective distance from the fission source. From this plot it is possible to make a conservative estimate of the correction factor to apply to damage data obtained with different neutron spectra. (auth)
Date: July 27, 1962
Creator: Claiborne, H.C.
Object Type: Report
System: The UNT Digital Library
Fundamental mechanisms in flue gas conditioning (open access)

Fundamental mechanisms in flue gas conditioning

This project is divided into four tasks. The Management Plan was developed in task 1. Task 2, Evaluation of Mechanisms in FGD Sorbent and Ash Interactions, focuses on the characteristics of binary mixtures of these distinct powders. Task 3, Evaluation of Mechanisms in Conditioning Agents and Ash, is designed to examine the effects of various conditioning agents on fine ash particles to determine the mechanisms by which these agents alter the physical properties of the ash. Tasks 2 and 3 began with an extensive literature search and the assembly of existing theories. This phase of the project is now complete. During the past quarter, initial preparations of laboratory equipment for laboratory testing have been made. A plan for initial laboratory tests has been submitted to the Project Manager for review. Laboratory testing will commence once these laboratory plans have been formally approved. The results of the work performed under task 2 and 3 will be included in a Flue Gas Conditioning Model that will be issued under task 4. The Final Report for the project will also be prepared under task 4.
Date: April 27, 1992
Creator: Snyder, T. R.; Robinson, M. S. & Bush, P. V.
Object Type: Report
System: The UNT Digital Library
Subsurface stabilization by grouting of a simulated underground tank (open access)

Subsurface stabilization by grouting of a simulated underground tank

A moisture barrier using water, sodium silicate, formamide, calcium chloride and penechem with a gel time of one-half hour was constructed around a simulated tank 10 feet deep by 10 feet diameter in the subsurface of the 200 West Area. As a test of the moisture barrier integrity, the volume which would normally be occupied by a tank was excavated and filled with water. The barrier was unable to contain the water. The failure to achieve a water-tight barrier was attributed to a leak in the floor grout.
Date: January 27, 1977
Creator: Wiater, P.J. & Higley, B.A.
Object Type: Report
System: The UNT Digital Library
Information systems for engineering sustainable development (open access)

Information systems for engineering sustainable development

The ability of a country to follow sustainable development paths is determined to a large extent by the capacity or capabilities of its people and its institutions. Specifically, capacity-building in the UNCED terminology encompasses the country's human, scientific, technological, organizational, institutional, and resource capabilities. A fundamental goal of capacity-building is to enhance the ability to pose, evaluate and address crucial questions related to policy choices and methods of implementation among development options. As a result the United Nations Conference on Environment and Development (UNCED) Agenda 21 planning process has identified the need for better methods by which information can be transferred between industrialized nations and developing nations. The reasons for better methods of information transfer include facilitating decisions related to sustainable development and building the capacity of developing nations to better plan their future in both an economical and environmentally sound manner. This paper is a discussion on mechanisms for providing information and technologies available for presenting the information to a variety of cultures and levels of technical literacy. Consideration is given to access to information technology as well as to the cost to the user. One concept discussed includes an Engineering Partnership'' which brings together the talents and resources …
Date: February 27, 1992
Creator: Leonard, R.S.
Object Type: Article
System: The UNT Digital Library
Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.
Date: October 27, 1987
Creator: Jha, M. C. & Berggren, M. H.
Object Type: Report
System: The UNT Digital Library
Analysis of well test data---Application of probabilistic models to infer hydraulic properties of fractures. [Contains list of standardized terminology or nomenclatue used in statistical models] (open access)

Analysis of well test data---Application of probabilistic models to infer hydraulic properties of fractures. [Contains list of standardized terminology or nomenclatue used in statistical models]

Statistical and probabilistic methods for estimating the probability that a fracture is nonconductive (or equivalently, the conductive-fracture frequency) and the distribution of the transmissivities of conductive fractures from transmissivity measurements made in single-hole injection (well) tests were developed. These methods were applied to a database consisting of over 1,000 measurements made in nearly 25 km of borehole at five sites in Sweden. The depths of the measurements ranged from near the surface to over 600-m deep, and packer spacings of 20- and 25-m were used. A probabilistic model that describes the distribution of a series of transmissivity measurements was derived. When the parameters of this model were estimated using maximum likelihood estimators, the resulting estimated distributions generally fit the cumulative histograms of the transmissivity measurements very well. Further, estimates of the mean transmissivity of conductive fractures based on the maximum likelihood estimates of the model's parameters were reasonable, both in magnitude and in trend, with respect to depth. The estimates of the conductive fracture probability were generated in the range of 0.5--5.0 percent, with the higher values at shallow depths and with increasingly smaller values as depth increased. An estimation procedure based on the probabilistic model and the maximum likelihood …
Date: September 27, 1991
Creator: Osnes, J. D. (RE/SPEC, Inc., Rapid City, SD (United States)); Winberg, A.; Andersson, J. E. & Larsson, N. A. (Sveriges Geologiska AB, Goeteborg (Sweden))
Object Type: Report
System: The UNT Digital Library
Upper limits on neutron bursts emitted from Ti pressurized D sub 2 gas cells (open access)

Upper limits on neutron bursts emitted from Ti pressurized D sub 2 gas cells

In a search for bursts of neutrons from Ti in pressurized D{sub 2} gas cells, no statistically significant deviations from the background were observed for events where five or more neutrons are detected over a ten day experiment, including 103 hours of counting with cells on, and 28 hours counting of various backgrounds. Up to four cells were used including some 60 grams of 662-Ti fillings in a pressurized cylinder with 40-60 atmosphere of D{sub 2} gas. Other Ti samples were used too. The samples were cooled to liquid nitrogen temperature and placed in front of the neutron detector while warming up to room temperature. Seven cooling cycles were used, for each sample. The neutron detector system included 12 liquid scintillator neutron detectors, arranged in a close packed geometry, with six detectors in the upper hemisphere and six in the lower hemisphere. A central detector placed 2 cm from the cells was used, in each hemisphere, as a scatterer for a time of flight coincidence measurement, yielding the total coincidence efficiency of {epsilon}=2{plus minus}1%. The system was also used in singles mode to allow for counting with large efficiency. A neutron event is characterized by measuring its pulse heights, pulse …
Date: October 27, 1989
Creator: Rugari, S. L.; France, R. H., III; Gai, M.; Lund, B. J.; Smolen, S. D.; Zhao, Z. et al.
Object Type: Report
System: The UNT Digital Library