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Status of /sup 241/Am recovery and purification at Los Alamos Scientific Laboratory

Description: Americium recovery was initiated at Los Alamos Scientific Laboratory (LASL) in the late 1940's. The early procedures separated gram quantities of americium from large amounts of impurities including plutonium and the rare earths. Ion exchange procedures were developed for further purification. Until recently, no routine processing of americium has been done at LASL for several years. The increasing demand for americium in oil-well logging instruments and other uses led LASL to develop and install a process to recover larger quantities of americium. The LASL process was developed around the chemistry of americium that had been elucidated both at LASL and at other facilities. Presently, the americium feed is obtained as a by-product from a plutonium purification process at the new plutonium facility at LASL. This feed filtrate from a peroxide precipitation process is precipitated as a slurry of hydroxides, filtered, dissolved in nitric acid, and passed through an anion exchange column to remove any residual plutonium. The americium, contained in the effluent, is precipitated as the oxalate and calcined to the oxide. Americium is also available in other highly salted acidic process streams. These should lend themselves to solvent extraction. Developmental work has been promising, and a dibutyl butyl phosphate-kerosene extraction process is being brought on-line.
Date: January 1, 1980
Creator: Ramsey, H.D.; Clifton, D.G.; Hayter, S.W.; Penneman, R.A. & Christensen, E.L.
Partner: UNT Libraries Government Documents Department

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

Novel 15. 9-micron source. [/sup 15/ND/sub 3/ laser]

Description: Laser emission has been generated in /sup 15/ND/sub 3/ by pumping at 860.4 cm/sup -1/. Strong laser action has been observed at 123 cm/sup -1/, 109 cm/sup -1/ and, with up to 10 millijoules extracted, at 628.1 cm/sup -1/. Spectroscopic analysis indicates that the pumping arises from, and the 628.1-cm/sup -1/ emission terminates on, the same rotational state. Analysis of the time histories of the three laser emissions as well as studies of laser output energies indicates that 15.9-micron output arises from a 4-wave type process. This system, in addition, clarifies the interpretation of earlier studies of CO/sub 2/-laser-pumped ammonia lasers.
Date: January 1, 1983
Creator: Buchwald, M.I.; Jones, C.R. & Nelson, L.Y.
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

Production of einsteinium and fermium in nuclear explosions

Description: Efforts devoted to searches for short-lived nuclides in the debris from large thermonuclear explosions are reviewed along with reactor production of Es and Fm. Results of underground tests are discussed along with odd-even yield variations, and future directions for heavy-element synthesis. (JRD)
Date: August 21, 1978
Creator: Hoff, R.W.
Partner: UNT Libraries Government Documents Department

Structural studies of polypeptides: Mechanism of immunoglobin catalysis and helix propagation in hybrid sequence, disulfide containing peptides

Description: Catalytic immunoglobin fragments were studied Nuclear Magnetic Resonance spectroscopy to identify amino acid residues responsible for the catalytic activity. Small, hybrid sequence peptides were analyzed for helix propagation following covalent initiation and for activity related to the protein from which the helical sequence was derived. Hydrolysis of p-nitrophenyl carbonates and esters by specific immunoglobins is thought to involve charge complementarity. The pK of the transition state analog P-nitrophenyl phosphate bound to the immunoglobin fragment was determined by [sup 31]P-NMR to verify the juxtaposition of a positively charged amino acid to the binding/catalytic site. Optical studies of immunoglobin mediated photoreversal of cis, syn cyclobutane thymine dimers implicated tryptophan as the photosensitizing chromophore. Research shows the chemical environment of a single tryptophan residue is altered upon binding of the thymine dimer. This tryptophan residue was localized to within 20 [Angstrom] of the binding site through the use of a nitroxide paramagnetic species covalently attached to the thymine dimer. A hybrid sequence peptide was synthesized based on the bee venom peptide apamin in which the helical residues of apamin were replaced with those from the recognition helix of the bacteriophage 434 repressor protein. Oxidation of the disufide bonds occured uniformly in the proper 1-11, 3-15 orientation, stabilizing the 434 sequence in an [alpha]-helix. The glycine residue stopped helix propagation. Helix propagation in 2,2,2-trifluoroethanol mixtures was investigated in a second hybrid sequence peptide using the apamin-derived disulfide scaffold and the S-peptide sequence. The helix-stop signal previously observed was not observed in the NMR NOESY spectrum. Helical connectivities were seen throughout the S-peptide sequence. The apamin/S-peptide hybrid binded to the S-protein (residues 21-166 of ribonuclease A) and reconstituted enzymatic activity.
Date: August 1, 1992
Creator: Storrs, R.W.
Partner: UNT Libraries Government Documents Department

Selection and breeding of corn to enhance associative bacterial nitrogen fixation

Description: We have increased, through screening and breeding, the ability of corn (maize, Zea mays L.) to support bacterial nitrogen fixation in or on corn roots. Isotopic N fixed from /sup 15/N/sub 2/ was found on the roots. Even though the nitrogen-fixing association depends on germ plasm from tropical corn, the activity can be bred into corn currently used in midwestern United States agriculture.
Date: January 1, 1980
Creator: Ela, S.W.; Anderson, M.A. & Brill, W.J.
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

Effect of interacting particles on primordial nucleosynthesis

Description: We modify the standard model for big-bang nucleosynthesis to allow for the presence of a generic particle species, i.e., one which maintains good thermal contact with either the photons or the light neutrino species throughout the epoch of primordial nucleosynthesis. The production of D, /sup 3/He, /sup 4/He, and /sup 7/Li is calculated as a function of the mass, degrees of freedom, and spin statistics of the generic particle. We show that in general, the effect of an additional generic species cannot simply be parameterized as the equivalent number of additional light neutrino species. The presence of generic particles also affects the predicted value for the neutrino-to-photon temperature ratio.
Date: May 1, 1986
Creator: Kolb, E.W.; Turner, M.S. & Walker, T.P.
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

An assessment of the base blanket for ITER

Description: Ideally, the ITER base blanket would provide the necessary tritium for the reactor to be self-sufficient during operation, while having minimal impact on the overall reactor cost, reliability and safety. A solid breeder blanket has been developed in CDA phase in an attempt to achieve such objectives. The reference solid breeder base blanket configurations at the end of the CDA phase has many attractive features such as a tritium breeding ratio (TBR) of 0.8--0.9 and a reasonably low tritium inventory. However, some concerns regarding the risk, cost and benefit of the base blanket have been raised. These include uncertainties associated with the solid breeder thermal control and the potentially high cost of the amount of Be used to achieve high TBR and to provide the necessary thermal barrier between the high temperature solid breeder and low temperature coolant. This work addresses these concerns. The basis for the selection of a breeding blanket is first discussed in light of the incremental risk, cost and benefits relative to a non-breeding blanket. Key issues associated with the CDA breeding blanket configurations are then analyzed. Finally, alternative schemes that could enhance the attractiveness and flexibility of a breeding blanket are explored.
Date: January 1, 1991
Creator: Raffray, A.R.; Abdou, M.A. & Ying, A.
Partner: UNT Libraries Government Documents Department