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Operating and maintenance experience in tritium environments

Description: This presentation is a summary of practical experience gained over more than twenty years from analyzing failures of process equipment operated in tritium and deuterium environments. Significant improvements have been achieved in design and procurement of new equipment, testing and selection of materials, and gradually more favorable maintenance experience. Preferred materials and inspection methods are described. 6 tabs.
Date: January 1, 1987
Creator: Tuer, G.L.
Partner: UNT Libraries Government Documents Department

Shipping container for tritiated water

Description: A reusable shipping container for Type B and large quantities of tritiated water has been designed and tested at Mound Facility. An inner and an outer container are used for shipping up to 100,000 Ci of tritium in water absorbed on molecular sieve, silica gel or commercial clay absorbent. The package is commonly called configuration-5 of the model AL-M1 shipping containers. It is the newest member of the AL-M1 family which currently also includes configurations 1 and 3. These other configurations are both for plutonium-239 and uranium-235. The common feature uniting the AL-M1 family is the 55-gal outer drum assembly which is the same for all configurations. The inner containers are quite dissimilar. A ''Safety Analysis Report for Packaging'' or SARP was prepared to qualify the new shipping container for DOT/DOE approval. That document is a formal safety analysis of all three AL-M1 insulated drum shipping container configurations. Together these are officially identified as USA/9507/BLF (ERDA-AL). The Certificate of Compliance has been issued and the SARP has been submitted to NRC for review. A description of the configuration-5 inner container is presented. In addition to the prototype used in testing, thirteen of these containers have been fabricated. One is retained at Mound Facility and twelve will be used at Sandia Laboratories, Livermore, to collect tritiated wastewater. This wastewater will be shipped to Mound for recovery or dispoal of the tritium.
Date: January 1, 1978
Creator: Watkins, R.A.; Rhinehammer, T.B. & Griffin, J.F.
Partner: UNT Libraries Government Documents Department

Comparison of the effects of inhaled {sup 239}PuO{sub 2} and {beta}- emitting radionuclides on the incidence of lung carcinomas in laboratory animals

Description: The health effects of inhaling radioactive particles when the lung is the primary organ irradiated were studied in rats and Beagle dogs. The animals were exposed to aerosols of {sup 239}PuO{sub 2} or fission-product radionuclides in insoluble forms and observed for their life span. Lung carcinomas were the primary late-occuring effect. The incidence rate for lung carcinomas was modeled using a proportional hazard rate model. Linear functions predominated below 5 Gy to the lung. The life-time risk for lung carcinomas per 10{sup 4} Gy for beta emitters was 60 for rats and 65 for dogs, and for {sup 239}PuO{sub 2} it was 1500 for rats and 2300 for dogs.
Date: December 31, 1991
Creator: Hahn, F. F.; Griffith, W. C.; Boecker, B. B.; Muggenburg, B. A. & Lundgren, D. L.
Partner: UNT Libraries Government Documents Department

Experiment to measure the electron neutrino mass using a frozen tritium source

Description: We are performing an experiment to determine the electron neutrino mass with the precision of a few eV by measuring the tritium beta decay energy distribution near the endpoint. Key features of the experiment are a 2 eV resolution electrostatic spectrometer and a high-activity frozen tritium source. It is important that the source have electronic wavefunctions which can be accurately calculated. These calculations can be precisely made for tritium and the HeT/sup +/ daughter ion and allow determination of branching fractions to 0.1% and energy of the excited states to 0.1 eV. We discuss the excited final molecular state calculations and describe the experimental apparatus. 2 references, 6 figures.
Date: March 1, 1985
Creator: Fackler, O.; Mugge, M.; Sticker, H.; White, R.M. & Woerner, R.
Partner: UNT Libraries Government Documents Department

Effects of tritium contamination in the FED/INTOR reactor hall

Description: The purpose of this study was to determine the constraints imposed on the FED/INTOR fusion plants by tritium contamination in the reactor hall. Limitations imposed by gamma-radiation levels and the maintenance philosophy adopted were included. The cost (capital and operation) required to maintain 5, 50, and 500 ..mu..Ci/m/sup 3/ was evaluated. Three different maintenance strategies (unsuited worker, suited worker and robotics) were suited to determine if tritium contamination placed a constraint on reactor availability.
Date: January 1, 1983
Creator: Finn, P.A. & Rogers, M.L.
Partner: UNT Libraries Government Documents Department

Measurement control administration for nuclear materials accountability

Description: In 1986 a measurement control program was instituted at Mound to ensure that measurement performance used for nuclear material accountability was properly monitored and documented. The organization and management of various aspects of the program are discussed. Accurate measurements are the basis of nuclear material accountability. The validity of the accountability values depends on the measurement results that are used to determine inventories, receipts, and shipments. With this measurement information, material balances are calculated to determine losses and gains of materials during a specific time period. Calculation of Inventory Differences (ID) are based on chemical or physical measurements of many items. The validity of each term is dependent on the component measurements. Thus, in Figure 1, the measured element weight of 17 g is dependent on the performance of the particular measurement system that was used. In this case, the measurement is performed using a passive gamma ray method with a calibration curve determined by measuring representative standards containing a range of special nuclear materials (Figure 2). One objective of a measurement control program is to monitor and verify the validity of the calibration curve (Figure 3). In 1986 Mound's Nuclear Materials Accountability (NMA) group instituted a formal measurement control program to ensure the validity of the numbers that comprise this equation and provide a measure of how well bulk materials can be controlled. Most measurements used for accountability are production measurements with their own quality assurance programs. In many cases a measurement control system is planned and maintained by the developers and operators of the particular measurement system with oversight by the management responsible for the results. 4 refs., 7 figs.
Date: January 31, 1991
Creator: Rudy, C.R.
Partner: UNT Libraries Government Documents Department

PITR: Princeton Ignition Test Reactor

Description: The principal objectives of the PITR - Princeton Ignition Test Reactor - are to demonstrate the attainment of thermonuclear ignition in deuterium-tritium, and to develop optimal start-up techniques for plasma heating and current induction, in order to determine the most favorable means of reducing the size and cost of tokamak power reactors. This report describes the status of the plasma and engineering design features of the PITR. The PITR geometry is chosen to provide the highest MHD-stable values of beta in a D-shaped plasma, as well as ease of access for remote handling and neutral-beam injection.
Date: December 1, 1978
Partner: UNT Libraries Government Documents Department

Calculated thickness of tungsten alloy required for specified attenuation of gamma radiation from sup 137 CS

Description: The traditional method of evaluating and calibrating health physics instruments is to use a calibrator that consists of a single high-activity gamma radiation source with different attenuators to select the radiation level desired for tesing. To have accurate radiation intensities inside the calibrator cavity, the attenuators must be designed from precise absorption calculations. This paper reports calculations made to determine the thickness of tungsten alloy metal required for specific attenuation. These calculations include the buildup contribution by secondary scattering radiation, and they are compared to values calculated with the buildup factor omitted. 3 refs., 2 figs., 3 tabs.
Date: January 1, 1991
Creator: Chiles, M.M.; Allin, G.W. & Pace, J.V. III.
Partner: UNT Libraries Government Documents Department

(University of California, Davis) annual report for radioimmunotherapy program, Year 4, (1986)

Description: The goal of this program is to answer the fundamental scientific questions for the development of an effective approach to delivering radiation therapy to cancer on antibody-based radiopharmaceuticals. These basic questions refer to the choice of antibody fragments related to their biokinetics, the variation of the biokinetics with variations in the radiochemistry of labeling and the radionuclide used to label, the radionuclide radiation dosimetry, and the feasibility calculated from quantitative imaging in patients and implementation of a proven kinetic model. To approach these problems this program has five discrete, but interrelated aims. Radionuclide choices for effective therapy for solid tumors and bone marrow infiltrating tumor cells; The development of radiochemistry to optimize tumor uptake and increase non-target tissue clearance of the radiopharmaceuticals; Further development and documentation of the peri-fusion system for screening antibodies for human tumor uptake, normal tissue cross-reactivity, and tissue stability of new antibody radiometal linkages; Quantitation in vivo of pharmacokinetics and radiation dosimetry for radioiodinated and radiometal chelate-labeled antibodies and fragments; and Verification of dosimetry predictions and therapy feasibility in patients using selected I-131 and Cu-67 radioimmunopharmaceuticals.
Date: January 28, 1986
Partner: UNT Libraries Government Documents Department

Conceptual design of a self-cooled Flibe blanket

Description: A self-cooled Flibe blanket concept has been developed. The problems associated with tritium breeding, tritium containment, and corrosion have been investigated and potential solutions developed. A highly efficient and compact blanket and power conversion system has been incorporated. The resulting system is low pressure with high thermal efficiency and is inherently safe.
Date: June 1, 1986
Creator: Sze, D.K.; Jung, J.; Cheng, E.T.; Piet, S. & Klein, A.
Partner: UNT Libraries Government Documents Department

Capsule calorimeter development report

Description: A capsule calorimeter has been designed, fabricated, and tested that is capable of measuring the rate of thermal energy generation of a capsule source with an accuracy of plus or minus five percent over a range of 300 watts to 1,000 watts of power. Three operating modes were investigated. The rate of temperature rise mode of operation was found to be the superior operating mode based on accuracy, time cycle, and simplicity of operation. This mode of operation is recommended for use in the encapsulation plant for performing calorimetric determinations on the strontium and cesium capsules that will be produced in the plant. The heat generation data collected by calorimetry will be used for isotopic assay of the capsule sources. The capsule calorimeter is specifically designed for installation into a remotely operated hot cell.
Date: October 2, 1972
Creator: Hall, J.C.
Partner: UNT Libraries Government Documents Department

Activation analysis of the compact ignition tokamak

Description: The US fusion program has completed the conceptual design of a compact tokamak device that achieves ignition. The high neutron wall loadings associated with this compact deuterium-tritium-burning device indicate that radiation-related issues may be significant considerations in the overall system design. Sufficient shielding will be requied for the radiation protection of both reactor components and occupational personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure to permit personnel access into the test cell after shutdown and limit the total activation of the test cell components. This paper describes the conceptual design of the igloo shield system and discusses the major neutronic concerns related to the design of the Compact Ignition Tokamak.
Date: January 1, 1986
Creator: Selcow, E.C.
Partner: UNT Libraries Government Documents Department

Differential gene expression in neurospora crassa cell types: amplification of rRNA genes. Progress report, July 1979-30 June 1980

Description: The significant results obtained during 1979 to 1980 of the current research program are as follows: (1) the differential rRNA gene amplification in germinated conidia of N.crassa was confirmed. N.crassa rDNAs showed differences in degrees of homology with isolated DNAs from other Neurospora species which could be due to heterogeneity in internal spacers. Studies with N.crassa rDNA clones were initiated to study their heterogeneities. The organization of the Institutional Biohazard Committee (IBC) for Recombinant DNA research was completed and necessary certifications for the laboratory and the workers were obtained in accordance with the P/sub 2/EK/sub 1/ containment regulation of N.I.H. Known 17S and 26S N.crassa rDNA probes are being used to detect differences, if any, in restriction cleavage sites in rDNAs of different cell types and developmental mutants of N.crassa. DNAs from these N.crassa cells are restricted with EcoR/sub 1/ and Hind III and cleaved fragments separated by gel electrophoresis are transferred into nitrocellulose papers. Experiments are underway now to see if there are any changes in cleavage sites by annealing with /sup 32/P or /sup 3/H-17S or 26S rDNA probes followed by autoradiography.
Date: January 1, 1980
Creator: Dutta, S.K.
Partner: UNT Libraries Government Documents Department

Development of a continuous duty cryopump

Description: The continuous output of large quantities of gases at low pressure from fusion reactors, principally helium and hydrogen isotopes, dictates the need for a high speed pumping system that operates continuously, efficiently, and automatically. A liquid helium-cooled cryopump operated by a microprocessor controller can meet these requirements. The prototype system described herein features a single cryopump with three distinct pumping units: two units for pumping the vacuum chamber arranged so that one unit is closed for regenerating while the other is pumping the chamber (100% redundancy); and a collector pump, which is a high speed cryopump for receiving the regenerated gas. The unit pumps deuterium but can be changed readily to a sorption pump for helium service.
Date: June 1, 1986
Creator: Sedgley, D.W.; Batger, T.H. & Call, W.R.
Partner: UNT Libraries Government Documents Department

Design study of a falling-liquid-film condenser under flow conditions of the Tritium Systems Test Assembly

Description: A computer code is developed and parametric studies are made for the design of a cryogenic falling liquid film condenser of potential application for separating helium from hydrogen isotopes in the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory (LANL). Pending experimental verification, a condenser suitable for TSTA flows would be approximately 1.5 cm maximum ID, tapering to 0.5 cm ID, by 2.4 m high, requiring 30 W of refrigeration at 19 K, and with a tritium inventory of 2 g.
Date: January 1, 1981
Creator: Kinoshita, M.; Bartlit, J.R. & Sherman, R.H.
Partner: UNT Libraries Government Documents Department

Design of a tritium pellet injector for TFTR

Description: The TFTR tritium pellet injector (TPI) is designed to provide a tritium pellet fueling capability with pellet speeds in the 1{minus} to 3 km/s-range for the TFTR D-T phase. The existing TFTR deuterium pellet injector is being modified at Oak Ridge National Laboratory to provide a fourshot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns a two -stage light gas gun driver. The pipe gun concept has been qualified for tritium operation by the tritium proof-of-principle injector experiments conducted on the Tritium Systems Test Assembly at Los Alamos National Laboratory. In these experiments, tritium and D-T pellets were accelerated to speeds near 1.5 km/s. The TPI is being designed for pellet sizes in the range from 3.43 to 4.0 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation will be controlled by a programmable logic controller. 7 refs., 4 figs.
Date: January 1, 1991
Creator: Milora, S.L.; Gouge, M.J.; Fisher, P.W.; Combs, S.K.; Cole, M.J.; Wysor, R.B. et al.
Partner: UNT Libraries Government Documents Department

Development of a fusion fuel cycle systems code

Description: The tritium inventory in a D-T fusion experiment, like ITER, may be the major hazard onsite. This tritium is distributed throughout various systems and components. A major thrust of safety work has been aimed at reducing these tritium inventories, or at least at minimizing the amount of tritium that could be mobilized. I have developed models for a time-dependent fuel cycle systems code, which will aid in directing designers towards safer, lower inventory designs. The code will provide a self-consistent picture of system interactions and system interdependencies, and provide a better understanding of how tritium inventories are influenced. A systems'' approach is valuable in that a wide range of parameters can be studied, and more promising regions of parameter space can be identified. Ultimately, designers can use this information to specify a machine with minimum tritium inventory, given various constraints. Here, I discuss the models that describe tritium inventory in various components as a function of system parameters, and the unique capabilities of a code that will implement them. The models are time dependent and reflect a level of detail consistent with a systems type of analysis. The models support both a stand-alone Tritium Systems Code, and a module for the SUPERCODE, a time-dependent tokamak systems code. Through both versions, we should gain a better understanding of the interactions among the various components of the fuel cycle systems.
Date: January 1, 1991
Creator: Brereton, S.J. (Lawrence Livermore National Lab., CA (United States))
Partner: UNT Libraries Government Documents Department

Cancer radioimmunotherapy: Development of an effective approach

Description: The objective of this program is the development of effective approaches for delivering radiation therapy to patients with cancer using radiopharmaceuticals produced from monoclonal antibodies. One major achievement of this program has been the development of a new, Cu-67 chelator (Teta). This chelator firmly holds copper even in the presence of competitive serum proteins. Copper has proven to be labile with other chelators. Also, a single photon emission tomographic camera was purchased with University and philanthropic funds specifically for this program. This allows full-time developmental work on quantitative imaging approaches and in vivo kinetics of our various radiopharmaceutical antibody products. The pharmakinetics of I-123 antibody and antibody fragments have been obtained in patients utilizing quantitative imaging and have demonstrated significant differences as well as the need for long- term studies with I-131 and Cu-67.
Date: January 1, 1985
Creator: DeNardo, S.J.
Partner: UNT Libraries Government Documents Department

Low-temperature helium embrittlement of tritium-charged stainless steel

Description: Specimens of Type 21-6-0 stainless steel were charged with tritium or protium to determine the effect of hydrogen isotope exposure on ductility. Specimens charged with either tritium or protium showed a 40% loss in ductility when tested immediately after charging. Protium-charged specimens stored 5.5 years at 250/sup 0/K showed no additional loss in ductility. However, tritium-charged specimens suffered an additional loss of 86% in ductility when similarly stored.
Date: January 1, 1980
Creator: Rawl, D.E. Jr.; Caskey, G.R. Jr. & Donovan, J.A.
Partner: UNT Libraries Government Documents Department

Measurement of the energy dependent beta asymmetry in the decay of /sup 8/Li

Description: Progress is reported on a new measurement of the beta decay asymmetry in /sup 8/Li. Polarized /sup 8/Li is produced via the reaction /sup 7/Li(d,p)/sup 8/Li using vector polarized deuterons from a crossed beam polarized source. Plastic scintillation electron counters are used to measure asymmetry, tensor polarization correlation and to monitor beam current. Results are graphed and systematic error sources are discussed. 4 refs. (LEW)
Date: January 1, 1985
Creator: Bigelow, R.A.; Quin, P.A.; Freedman, S.J. & Napolitano, J.
Partner: UNT Libraries Government Documents Department

Maintainability features of the compact ignition tokamak

Description: The Compact Ignition Tokamak (CIT) is a deuterium-tritium (D-T) device envisaged to be the next experimental reactor in the US Fusion Program. The reactor will initially operate in a nonactivated hydrogen phase for approximately two years. This will permit verification of the integrity of the total system and allow hands-on repair to equipment which has experienced shakedown and early operation failures. Once D-T operations commence, reactor maintenance will require remote handling techniques. An evaluation has been completed to determine what maintenance operations must be performed on the CIT. A maintenance philosophy has been developed which is based upon the use of manipulator systems and robotics in the test cell. Replacement of life-limited equipment will be accomplished using a modular design approach for components, with simple remotely operable interfaces. Examples of operations to be done remotely include: (1) replacing of rf antennae and Faraday shields, (2) uncoupling diagnostic and fueling penetrations, (3) removing of all port covers, and (4) replacing first wall armor tiles, optical mirrors, and vacuum windows.
Date: January 1, 1986
Creator: Spampinato, P.T. & Bushnell, C.W.
Partner: UNT Libraries Government Documents Department

Transient getter scheme for the Tokamak Fusion Test Reactor

Description: The ability of the Tokamak Fusion Test Reactor (TFTR) to attain the largest fusion power gain depends critically on minimizing plasma contamination and controlling the densities of the reacting deuterium and tritium. Experiments on a number of tokamaks have demonstrated that gettering over an appreciable surface area (greater than or equal to 10%) of the vacuum vessel greatly facilitates both of these objectives. One particular problem in implementing a surface pumping system in TFTR, however, is a restriction on the maximum allowable tritium content of the getter. This restriction could require regeneration of the absorbed tritium after as few as 50 machine pulses. We have developed a scheme utilizing SAES Zr/Al getter modules which obviates the need for such frequent interruptions of machine operation by taking advantage of the pulsed operation of TFTR. With the Zr/Al getter at temperatures between 500/sup 0/C to 600/sup 0/C it is possible to achieve a quasi-steady state in the tritium loading where the quantity of tritium desorbed between pulses is equal to the quantity which is absorbed during a pulse. Since frequent thermal cycling is not required, this scheme also reduces the possibility of Zr/Al getter material fatigue.
Date: January 1, 1980
Creator: Cecchi, J.L.; Cohen, S.A. & Sredniawski, J.J.
Partner: UNT Libraries Government Documents Department

Deuterium and tritium fuelding in an ETF/INTOR plasma with divertor

Description: Fueling by pellets and neutral gas in the presence of a divertor is examined with a one-dimensional multispecies transport code. Deuterium, tritium, and alpha particles are treated as independent thermal species. With an efficiently operating divertor, it becomes impossible to maintain high plasma density (anti n approx. 10/sup 14/ cm/sup -3/) with neutral gas fueling alone because of the high probability of the gas being ionized in the scrapeoff layer. Pellet fueling significantly reduces the particle load on the divertor and, with feedback control, can maintain the plasma density at the desired level. A low level of deuterium gas fueling can then be used to maintain the density of the scrapeoff layer and increase shielding against sputtered impurities. Even with an effective shielding divertor, the energy and particle fluxes to the first wall from both charged and neutral particles may be significant. The fluctuations at the plasma edge and in the scrapeoff layer introduced by the pellets cause the particle and energy fluxes to the divertor and first wall to fluctuate. This makes simulation more difficult but may be used to experimentally determine radial and parallel transport properties in the scrapeoff layer. Recommendations for further study are made.
Date: January 1, 1980
Creator: Houlberg, W.A.; Howe, H.C. & Attenberger, S.E.
Partner: UNT Libraries Government Documents Department

Advanced fuel concepts and applications

Description: Despite their more stringent plasma heating and confinement requirements, advanced fuel (AF) fusion cycles potentially offer improved environmental compatibility and lower costs. This comes about by elimination of tritium breeding requirements and by a reduction in neutron flux (hence, activation and radiation damage). Also a larger energy fraction carried by charged particles makes direct energy conversion more suitable. As a first application, a symbiotic system of semi-catalyzed-deuterium fueled hybrid fuel factories, supplying both fissle fuel to light water reactors and /sup 3/He to D-/sup 3/He satellite fusion reactors, is proposed. Subsequently, an evolution into a system of synfuel factories with satellite D-/sup 3/He reactors is envisioned.
Date: January 1, 1981
Creator: Miley, G.H.
Partner: UNT Libraries Government Documents Department