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Attributes measurements by calorimetry in 15 to 30 minutes

Description: An analysis of the early portion of the power-history data collected with both of the IAEA's air-cooled bulk calorimeters has demonstrated that such calorimeters can measure the power from preheated containers of plutonium oxide with an accuracy of 2 to 5% in 15 to 30 minutes. Material accountancy at plutonium facilities has a need for such a capability for measurement of Pu scrap. Also, the International Atomic Energy Agency (IAEA) could use just two calorimeters and a gamma-ray assay system for reliable variables and attributes measurements of plutonium mass during a two-day physical-inventory verification (PIV) at a mixed-oxide (MOX) fuel-fabrication facility. The assay results would be free of the concerns about sample moisture, impurities, and geometry that previously have limited the accuracy of assays based on neutron measurements.
Date: January 1, 1987
Creator: Fiarman, S. & Perry, R.B.
Partner: UNT Libraries Government Documents Department

Analysis of Fuel Element Core Blanks for Argonne Low Power Reactor by Gamma Counting

Description: A technique based on a determinaiion of the differential counting rate exhibited by the 184-kev gamma radiation associated with the decay of U/sup 235/ was developed for the determination of the U/sup 235/ content in Argonne Low Power Reactor fuel element core blanks. The Argonne Low Power Reactor core blanks were an aluminum-highly enriched uranium alloy containing 17.5 weight per cent uranium (approximately 4 g U/sup 235/) having the following dimensions: length, 6.875 inches, width, 3.31 inches, and thickness, 0.200 inch. The gamma- ray spectrum emitied by uranium is rather complex. Using a scintillation spectrometer and scanning the spectrum, the energy is found to be concentrated primarily in two regions, at 184 and 90 kev. The 184-kev gamma rays result primarily from the decay of U/sup 235/ The gammas in the 90-kev region result from the U/sup 235/ decay and daughter products of U/sup 238/ and U/sup 235/. Using a pulse-height analyzer, it is possibie to select the desired radiation emitted from the source and determine the counting rate for a given source. In this work the 184-kev gamma radiation was counted to determine the amount of U/ sup 235/ present in the individual core blanks. (auth)
Date: December 1, 1959
Creator: McGonnagle, W. J. & Perry, R. B.
Partner: UNT Libraries Government Documents Department

3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

Description: A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predictions will be validated against test data using the ANL bulk calorimeter. 11 refs., 6 figs.
Date: January 1, 1989
Creator: Elias, E.; Kaizermann, S.; Perry, R.B. & Fiarman, S.
Partner: UNT Libraries Government Documents Department

NONDESTRUCTIVE TESTS OF COMPONENTS OF EBR-I, CORE IV

Description: Eddy-current and ultrasonic tests on zirconium rod stock and wire, Zircaloy-2 tubing and rod stock, and stainless steel tubing for use in various core compoments are summarized. Eddy-current tests were also performed on the NaK annulus of assembled blanket elements. (D.C.W.)
Date: October 1, 1963
Creator: Selner, R.H.; Renken, C.J.; Perry, R.B. & Balaramamoorthy, K.
Partner: UNT Libraries Government Documents Department

Calorimetric measurement of afterheat in target materials for the accelerator production of tritium

Description: The estimate of afterheat in a spallation target of lead (Pb) or tungsten (W), by calorimetry, is the purpose of this experiment in support of the Accelerator Production of Tritium (APT). Such measurements are needed to confirm code calculations, these being the only practical way of gaining this type of information in a form suitable to aid the design of the APT machine. Knowledge of the magnitude and duration of afterheat resulting from decay of activation products produced by proton bombardment of the target is necessary to quantify APT safety assumptions, to design target cooling and safety systems, and to reduce technical risk. Direct calorimetric measurement of the afterheat for the appropriate incident proton energies is more reliable than the available alternative, which is indirect, based on data from gamma-ray spectroscopy measurements. The basic concept, a direct measurement of decay afterheat which bypasses the laborious classical way of determining this quantity, has been demonstrated to work. The gamma-ray energy given off by the decay products produced in the activation of lead or tungsten with high-energy protons apparently does represent a significant fraction of the total decay energy. A calorimeter designed for measurement of isotopes decaying by alpha emission must be modified to reduce energy lost with escaping gamma rays. Replacement of the aluminum liner with a tungsten liner in the SSC measurement chamber resulted in a 270% increase in measured heat, proving that the energy loss in the earlier (1992) measurements was significant. Gamma-ray measurements are needed to confirm the gamma-ray absorption calculations for the calorimeter to determine the correction for loss of heat due to transmission of high-energy gamma rays through the calorimeter walls. The experiments at BLIP have shown that calorimetry can be a useful tool in measuring the afterheat in APT target materials.
Date: June 1, 1994
Creator: Perry, R.B. & Zucker, M.S.
Partner: UNT Libraries Government Documents Department

Nondestructive assay system for use in decommissioning a plutonium-handling facility

Description: Argonne National Laboratory is decommissioning a facility used to fabricate reactor fuel elements. The equipment is contaminated with alpha emitters at levels up to 10/sup 12/ dpm/100 cm/sup 2/. The objective of decontamination is to reduce the TRU concentrations below 10 nCi/g of waste. A portable NDA procedure using NaI(T1) gamma-spectrometric techniques was selected to measure the residual Pu and /sup 241/Am in the glove boxes. Assays were performed at different stages in the decontamination process to estimate the detection system sensitivity and the effectiveness of the cleaning efforts.
Date: July 1, 1979
Creator: Roche, C.T.; Vronich, J.J.; Bellinger, F.O. & Perry, R.B.
Partner: UNT Libraries Government Documents Department

ANL small-sample calorimeter system design and operation

Description: The Small-Sample Calorimetric System is a portable instrument designed to measure the thermal power produced by radioactive decay of plutonium-containing fuels. The small-sample calorimeter is capable of measuring samples producing power up to 32 milliwatts at a rate of one sample every 20 min. The instrument is contained in two packages: a data-acquisition module consisting of a microprocessor with an 8K-byte nonvolatile memory, and a measurement module consisting of the calorimeter and a sample preheater. The total weight of the system is 18 kg.
Date: July 1, 1978
Creator: Roche, C.T.; Perry, R.B.; Lewis, R.N.; Jung, E.A. & Haumann, J.R.
Partner: UNT Libraries Government Documents Department

ANL four-meter calorimeter design and operation manual

Description: The four-meter fuel rod calorimetric system measures the thermal power produced by radioactive decay of fuel rods containing Pu. The Pu mass is related to the measured power through the weighted average of the product of the isotopic decay energies and the decay constants of the Pu isotopes present. U content has no effect since the thermal power produced by the U nuclides is insignificant when compared to Pu. Radiations from Pu are alpha particles and low-energy photons. This calorimeter will measure samples producing power up to 1.5 watts at a rate of one sample every 120 min. The instrument consists of a data-acquisition module made up of a microprocessor, with an 8K-byte nonvolatile memory, a control cabinet and the calorimeter chamber. (FS)
Date: February 1, 1980
Creator: Perry, R.B.; Lewis, R.N.; Youngdahl, G.A.; Jung, E.A. & Roche, C.T.
Partner: UNT Libraries Government Documents Department

Test and Evaluation of the Argonne BPAC10 Series Air Chamber Calorimeter Designed for 20 Minute Measurements

Description: This paper is the final report on DOE-OSS Task ANLE88002 Fast Air Chamber Calorimetry.'' The task objective was to design, construct, and test an isothermal air chamber calorimeter for plutonium assay of bulk samples that would meet the following requirements for sample power measurement: average sample measurement time less than 20 minutes. Measurement of samples with power output up to 10 W. Precision of better than 1% RSD for sample power greater than 1 W. Precision better than 0.010 watt SD, for sample power less than 1 W. This report gives a description of the calorimeter hardware and software and discusses the test results. The instrument operating procedure, included as an appendix, gives examples of typical input/output and explains the menu driven software.
Date: October 1990
Creator: Perry, R. B.; Fiarman, Sidney; Jung, Erwin A. & Cremers, Teresa
Partner: UNT Libraries Government Documents Department

Calorimetry measurements in less than 20 minutes

Description: Argonne National Laboratory has developed a new series of 10 watt Bulk Plutonium Assay Calorimeters (BPAC10). The calorimeter measures bulk samples of plutonium bearing material in containers up to 5in. in diameter and 7in. high. The average measurement time is 19.7 minutes compared to 2--9 hours for the same sample measured in a water bath calorimeter. Measurement precision in the range of 1--10 watts is 1% to 0.1% and it is 0.010 watt for sample power less than 1 watt. BPAC10 series calorimeters are in use in two plutonium facilities at the EG G Rocky Flats Plant and at the Los Alamos National Laboratory TA55 Plutonium Facility. The paper presents a description of the calorimeter, discusses operating experience at Los Alamos, and presents a comparison of data on typical samples measured with both types of calorimeters. 5 refs., 5 figs., 1 tab.
Date: January 1, 1991
Creator: Perry, R.B. (Argonne National Lab., IL (United States)) & Cremers, T. (Los Alamos National Lab., NM (United States))
Partner: UNT Libraries Government Documents Department

A Nondestructive Assay System for use in Decommissioning a Plutonium-Handling Facility

Description: Argonne National Laboratory is decommissioning a facility used to fabricate reactor fuel elements. The equipment is contaminated with alpha emitters. The objective of decontamination is to reduce the TRU concentrations below 10 nCi/g of waste. A portable NDA procedure using Na I (TI ) gamma-spectrometric techniques was selected to measure the residual Pu and 2i 1 Am in the glove boxes. Assays were performed at different stages in the decontamination process to estimate the detection system sensitivity and the effectiveness of the cleaning efforts.
Date: July 1979
Creator: Argonne National Laboratory. Special Materials Division. Nondestructive Assay Section.
Partner: UNT Libraries Government Documents Department

Autoradiographic Technique for Rapid Inventory of Plutonium-Containing Fast Critical Assembly Fuel

Description: A nondestructive autoradiographic technique is described which can provide a verification of the piece count and the plutonium content of plutonium-containing fuel elements. This technique uses the spontaneously emitted gamma rays from plutonium to form images of fuel elements on photographic film. Autoradiography has the advantage of providing an inventory verification without the opening of containers or the handling of fuel elements. Missing fuel elements, substitution of nonradioactive material, and substitution of elements of different size are detectable. Results are presented for fuel elements in various storage configurations and for fuel elements contained in a fast critical assembly.
Date: October 1977
Creator: Brumbach, S. B. & Perry, R. B.
Partner: UNT Libraries Government Documents Department

Autoradiography as a Safeguards Inspection Technique for Unirradiated LWR Fuel Assemblies

Description: A nondestructive autoradiographic method is described which can provide a verification that rods in the interior of unirradiated LWR fuel assemblies contain low-enriched uranium. Sufficient absorber must be used to reduce contributions to image density by beta radiation from uranium-238 daughters. When appropriate absorbers are used, the density of the image of a uranium-containing fuel rod is proportional to the uranium-235 enrichment in that rod. Exposure times as short as 1.5 hours can be achieved by using fast film and intensifying screens. Methods are discussed for reducing contributions to the image density of any single rod from radiation produced by all other rods in the assembly. The technique is useful for detecting missing rods, dummy rods, and rods containing depleted uranium. These defects can be detected by visual inspection of the autoradiographs. In its present state of development, the technique is not sensitive enough to reliably detect the difference between the various uranium-235 enrichments encountered in current BWR fuel assemblies. Results are presented for field tests of the technique at BWR and PWR facilities.
Date: May 1978
Creator: Brumbach, S. B. & Perry, R. B.
Partner: UNT Libraries Government Documents Department

Bulk-assay calorimeter: Part 1. System design and operation. Part 2. Calibration and testing

Description: The Bulk-Assay Calorimeter is designed to measure the thermal power emitted by plutonium-containing samples. The sample power range of the instrument is 1.4 to 22.4 W. The instrument package consists of the calorimeter measurement chamber, the control circuit power bin, and the data acquisition system. Two sample preheating chambers and five calorimeter canisters for containing the samples are included. A set of 32 test points which monitor voltages at points within the calorimeter and its control circuitry are accessed by the data acquisition system. The use of the test points is described. System start-up and checkout are described. Sample assay and preheater operation procedures are given. The data acquisition system and data analysis software are described. The calorimeter was calibrated at 23 points with heat sources from 1.4 to 22.4 watts. The combined measurement error varied with sample power from 1.4% to 0.1% over the range of calibration measurements. Circuit diagrams for the calorimeter and schematics for the data acquisition system are included. (LEW)
Date: January 1, 1982
Creator: Perry, R.B.; Roche, C.T.; Harkness, A.L.; Winslow, G.H.; Youngdahl, G.A.; Lewis, R.N. et al.
Partner: UNT Libraries Government Documents Department

Test and evaluation of the Argonne BPAC10 Series air chamber calorimeter designed for 20 minute measurements

Description: This paper is the final report on DOE-OSS Task ANLE88002 Fast Air Chamber Calorimetry.'' The task objective was to design, construct, and test an isothermal air chamber calorimeter for plutonium assay of bulk samples that would meet the following requirements for sample power measurement: average sample measurement time less than 20 minutes. Measurement of samples with power output up to 10 W. Precision of better than 1% RSD for sample power greater than 1 W. Precision better than 0.010 watt SD, for sample power less than 1 W. This report gives a description of the calorimeter hardware and software and discusses the test results. The instrument operating procedure, included as an appendix, gives examples of typical input/output and explains the menu driven software. Sample measurement time of less than 20 minutes was attained by pre-equilibration of the samples in low cost precision preheaters and by prediction of equilibrium measurements. Tests at the TA55 Plutonium Facility at Los Alamos National Laboratory, on typical samples, indicates that the instrument meets all the measurement requirements.
Date: October 1, 1990
Creator: Perry, R.B.; Fiarman, S.; Jung, E.A. (Argonne National Lab., IL (USA)) & Cremers, T. (Los Alamos National Lab., NM (USA))
Partner: UNT Libraries Government Documents Department

Plutonium Calorimetry and SNM Holdup Measurements, Progress Report: March 1976-August 1976

Description: The calorimetric instrumentation developed at Argonne National Laboratory (ANL) for making nondestructive measurements of the plutonium content of fuel rods is discussed. Measurements with these instruments are relatively fast (i.e., 15 to 20 minutes) when compared to the several hours usually required with more conventional calorimeters and for this reason are called ''fast-response.'' Most of the discussion concerns the One-Meter and the Four-Meter Fuel-Rod Calorimeters and the Analytical Small-Sample Calorimeter. However, to provide some background and continuity where needed, a small amount of discussion is devoted to the three earlier calorimeters which have been described previously in the literature. A brief review is presented of the literature on plutonium holdup measurements. The use of gamma-ray techniques for holdup measurements is discussed and results are given for the determination of sample thickness using the ratio of intensities of high- and low-energy gamma rays. The measurements cover the plutonium metal thickness range from 0.001 to 0.120 inches. The design of a gamma-ray collimator with 37 parallel holes is also discussed. Neutron-counting experiments using BF3 proportional counters embedded in two polyethylene slabs are described. This detector configuration is characterized for its sensitivity to sample and background plutonium, counting both coincidence (fission) and total neutrons. In addition, the use of infrared imaging devices to measure small temperature differences is considered for locating large amounts of plutonium holdup and also for performing fast attribute checks for fabricated fuel elements.
Date: February 1977
Creator: Brumbach, S. B.; Finkbeiner, A. M.; Lewis, R. N. & Perry, R. B.
Partner: UNT Libraries Government Documents Department

A Portable Calorimeter System for Nondestructive Assay of Mixed-Oxide Fuels

Description: Calorimetric assay provides a precise, nondestructive method to determine sample plutonium content based on the heat emitted by decaying radionuclides. This measurement, in combination with a gamma-spectrometer analysis of sample isotopic content, yields the total sample plutonium mass. The technique is applicable to sealed containers and is essentially independent of sample matrix configuration and elemental composition. Conventional calorimeter designs employ large water-bath heat sinks and lack the portability needed by inspection personnel. The ANL air-chamber isothermal calorimeters are low-thermal-capacitance devices which eliminate the need for large constant-temperature heat sinks. These instruments are designed to use a feedback system that applies power to maintain the sample chamber at a constant electrical resistance and, therefore, at a constant temperature. The applied-power difference between a plutonium-containing sample and a blank determines the radioactive-decay power. The operating characteristics of a calorimeter designed for assaying mixed-oxide powders, fuel pellets, and plutonium-containing solutions are discussed. This device consists of the calorimeter, sample pre-heater, and a microprocessor-controlled data-acquisition system. The small-sample device weighs 18 kg and has a measurement cycle of 20 min, with a precision of 0.1% at 10 mW. A 100-min gamma-ray measurement gives the specific power with a precision of better than 1% for samples containing 1 to 2 g of plutonium.
Date: 1978
Creator: Roche, C. T.; Perry, R. B.; Lewis, R. N.; Jung, E. A. & Haumann, J. R.
Partner: UNT Libraries Government Documents Department