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Proceedings -- US Russian workshop on fuel cell technologies

Description: On September 26--28, 1995, Sandia National Laboratories sponsored the first Joint US/Russian Workshop on Fuel Cell Technology at the Marriott Hotel in Albuquerque, New Mexico. This workshop brought together the US and Russian fuel cell communities as represented by users, producers, R and D establishments and government agencies. Customer needs and potential markets in both countries were discussed to establish a customer focus for the workshop. Parallel technical sessions defined research needs and opportunities for collaboration to advance fuel cell technology. A desired outcome of the workshop was the formation of a Russian/American Fuel Cell Consortium to advance fuel cell technology for application in emerging markets in both countries. This consortium is envisioned to involve industry and national labs in both countries. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: April 1, 1996
Creator: Baker, B. & Sylwester, A.
Partner: UNT Libraries Government Documents Department

Status of the uranium upgrade of ATLAS

Description: The ATLAS Positive Ion Injector (PII) is designed to replace the tandem injector for the ATLAS heavy-ion facility. When the PII project is complete, ATLAS will be able to accelerate all ions through uranium to energies above the Coulomb barrier. PII consists of an ECR ion source on a 350 KV platform and a very low-velocity superconducting linac. The linac is composed of an independently-phased array of superconducting four-gap interdigital resonators which accelerate over a velocity range of .007c to .05c. the PII project is approximately 75% complete. Beam tests and experiments using the partially completed PII have demonstrated that the technical design goals are being met. The design, construction status, and results of recent operational experience using the PII will be discussed. 10 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Bollinger, L.M.; Billquist, P.J.; Bogaty, J.M.; Clifft, B.E.; Markovich, P.; Munson, F.H. et al.
Partner: UNT Libraries Government Documents Department

Comparison of effectiveness of sub-slab ventilation systems for indoor radon mitigation: A numerical study; Comparaison a l`aide d`un outil numerique de l`efficacite des systemes de ventilation active du sol limitant la penetration du radon dans l`habitat

Description: The functioning of an active sub-slab ventilation system (SVS) has been studied successfully with the help of a previously evaluated numerical model. The parameters explored are the permeability of the sub-slab and the gravel placed beneath it, the amplitude of applied pressure at the installation point of the system and the functioning method: depressurization or pressurization. The mechanisms contributing to the success of the two systems are identified. This numerical study shows that the presence of a layer of gravel beneath the sub-slab considerably improves the performance of the SVS. Considered separately from the extremely permeable sub-slabs, the depressurization systems perform better than the pressurization systems. 17 refs. [Francais] Le fonctionnement des Systemes de Ventilation active du Sol (SVS) a ete etudie a l`aide d`un outil numerique precedemment evalue avec succes. Les parametres explores sont les permeabilites du sol et du gravier place sous plancher bas, l`amplitude de la pression appliquee au point d`installation du systeme, et le mode de fonctionnement: Depressurisation ou Pressurisation. Les mecanismes contribuant au succes des deux systemes sont identifies. Cette etude numerique montre que la presence d`une couche de gravier sous plancher bas ameliore de facon considerable les performances des SVS. Mis a part le cas des sols extremement permeables, les systemes de Depressurisation ont de meilleures performances que les systemes de Pressurisation. 17 refs.
Date: April 1, 1992
Creator: Bonnefous, Y. C.; Gadgil, A. J. & Allard, F.
Partner: UNT Libraries Government Documents Department

Evolution of Sarcoma 37 in cf1 Rats. Biological Aspects of the Spontaneous Cure of Tumors Studied After Irradiation and Administration of Immune Serum. Evolucao Do Sarcoma 37 Em Muganhos cf1. Aspectos Biologicos Da Cura Espontianea Do Tumor Estudados Apos Irradiacao E Administracao De Soro Imune

Description: Transplants of sarcoma 37 were studied in regard to spontaneous regression of the tumor after irradiation and after the administration of immune serum. The following results were obtained: 1. Of 809 animals, 99% developed the tumor after transplantation; 2. The number of cells transplanted did not influence the growth rate, the percentage of spontaneous regressions, or the life spans of the animals; 3. Reimplantation of the tumor into mice which had previously rejected the tumor resulted in very few successful transplants; 4. The resistance of these mice to further attempts at implantation could not be altered by previous irradiation; 5. Animals transplanted for the first time suffer a faster evolution of the tumor, shortened life span, and a diminution of spontaneous regressions if they have been irradiated prior to transplantation (400r whole body); and, 6. Resistance to tumor growth could not be transferred passively in serum of mice which had rejected the tumor.
Date: December 1, 1965
Creator: Clode, William H.
Partner: UNT Libraries Government Documents Department

Thermophotovoltaic Spectral Control

Description: Spectral control is a key technology for thermophotovoltaic (TPV) direct energy conversion systems because only a fraction (typically less than 25%) of the incident thermal radiation has energy exceeding the diode bandgap energy, E{sub g}, and can thus be converted to electricity. The goal for TPV spectral control in most applications is twofold: (1) Maximize TPV efficiency by minimizing transfer of low energy, below bandgap photons from the radiator to the TPV diode. (2) Maximize TPV surface power density by maximizing transfer of high energy, above bandgap photons from the radiator to the TPV diode. TPV spectral control options include: front surface filters (e.g. interference filters, plasma filters, interference/plasma tandem filters, and frequency selective surfaces), back surface reflectors, and wavelength selective radiators. System analysis shows that spectral performance dominates diode performance in any practical TPV system, and that low bandgap diodes enable both higher efficiency and power density when spectral control limitations are considered. Lockheed Martin has focused its efforts on front surface tandem filters which have achieved spectral efficiencies of {approx}83% for E{sub g} = 0.52 eV and {approx}76% for E{sub g} = 0.60 eV for a 950 C radiator temperature.
Date: June 9, 2004
Creator: DePoy, DM; Fourspring, PM; Baldasaro, PF; Beausang, JF; Brown, EJ; Dashiel, MW et al.
Partner: UNT Libraries Government Documents Department

Processing and waste disposal representative for fusion breeder blanket systems

Description: This study is an evaluation of the waste handling concepts applicable to fusion breeder systems. Its goal is to determine if breeder blanket waste can be disposed of in shallow land burial, the least restrictive method under US Nuclear Regulatory regulations. The radionuclides expected in the materials used in fusion reactor blankets are described, as are plans for reprocessing and disposal of the components of different breeder blankets. An estimate of the operating costs involved in waste disposal is made.
Date: January 1, 1987
Creator: Finn, P.A. & Vogler, S.
Partner: UNT Libraries Government Documents Department

THE ATOMIC WEIGHTS COMMISSION AND ISOTOPIC ABUNDANCE RATIO DETERMINATIONS.

Description: Following Thomson's discovery of stable isotopes in non-radioactive chemical elements, the derivation of atomic weight values from mass spectrometric measurements of isotopic abundance ratios moved very slowly. Forty years later, only 3 1/2 % of the recommended values were based on mass spectrometric measurements and only 38% in the first half century. It might be noted that two chemical elements (tellurium and mercury) are still based on chemical measurements, where the atomic weight value calculated from the relative isotopic abundance measurement either agrees with the value from the chemical measurement or the atomic weight value calculated from the relative isotopic abundance measurement falls within the uncertainty of the chemical measurement of the atomic weight. Of the 19 chemical elements, whose atomic weight is based on non-corrected relative isotopic abundance measurements, five of these are two isotope systems (indium, iridium, lanthanum, lutetium and tantalum) and one is a three-isotope system (oxygen).
Date: August 7, 2005
Creator: HOLDEN, N. E.
Partner: UNT Libraries Government Documents Department

Solutions for Summer Electric Power Shortages: Demand Response andits Applications in Air Conditioning and Refrigerating Systems

Description: Demand response (DR) is an effective tool which resolves inconsistencies between electric power supply and demand. It further provides a reliable and credible resource that ensures stable and economical operation of the power grid. This paper introduces systematic definitions for DR and demand side management, along with operational differences between these two methods. A classification is provided for DR programs, and various DR strategies are provided for application in air conditioning and refrigerating systems. The reliability of DR is demonstrated through discussion of successful overseas examples. Finally, suggestions as to the implementation of demand response in China are provided.
Date: November 30, 2007
Creator: Han, Junqiao & Piette, Mary Ann
Partner: UNT Libraries Government Documents Department

Proceedings of the Chornobyl phytoremediation and biomass energy conversion workshop

Description: Many concepts, systems, technical approaches, technologies, ideas, agreements, and disagreements were vigorously discussed during the course of the 2-day workshop. The workshop was successful in generating intensive discussions on the merits of the proposed concept that includes removal of radionuclides by plants and trees (phytoremediation) to clean up soil in the Chornobyl Exclusion Zone (CEZ), use of the resultant biomass (plants and trees) to generate electrical power, and incorporation of ash in concrete casks to be used as storage containers in a licensed repository for low-level waste. Twelve years after the Chornobyl Nuclear Power Plant (ChNPP) Unit 4 accident, which occurred on April 26, 1986, the primary 4radioactive contamination of concern is from radioactive cesium ({sup 137}Cs) and strontium ({sup 90}Sr). The {sup 137}Cs and {sup 90}Sr were widely distributed throughout the CEZ. The attendees from Ukraine, Russia, Belarus, Denmark and the US provided information, discussed and debated the following issues considerably: distribution and characteristics of radionuclides in CEZ; efficacy of using trees and plants to extract radioactive cesium (Cs) and strontium (Sr) from contaminated soil; selection of energy conversion systems and technologies; necessary infrastructure for biomass harvesting, handling, transportation, and energy conversion; radioactive ash and emission management; occupational health and safety concerns for the personnel involved in this work; and economics. The attendees concluded that the overall concept has technical and possibly economic merits. However, many issues (technical, economic, risk) remain to be resolved before a viable commercial-scale implementation could take place.
Date: June 1, 1998
Creator: Hartley, J. & Tokarevsky, V.
Partner: UNT Libraries Government Documents Department

Multiprocessor data acquisition system

Description: A multiprocessor data acquisition system has been built to replace the single processor systems at the Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory. The multiprocessor system was needed to accommodate the higher data rates at IPNS brought about by improvements in the source and changes in instrument configurations. This paper describes the hardware configuration of the system and the method of task sharing and compares results to the single processor system.
Date: January 1, 1987
Creator: Haumann, J.R. & Crawford, R.K.
Partner: UNT Libraries Government Documents Department

Comparison of electric and magnetic quadrupole focusing for the low energy end of an induction-linac-ICF (Inertial-Confinement-Fusion) driver

Description: This report compares two physics designs of the low energy end of an induction linac-ICF driver: one using electric quadrupole focusing of many parallel beams followed by transverse combining; the other using magnetic quadrupole focusing of fewer beams without beam combining. Because of larger head-to-tail velocity spread and a consequent rapid current amplification in a magnetic focusing channel, the overall accelerator size of the design using magnetic focusing is comparable to that using electric focusing.
Date: April 1, 1987
Creator: Kim, C.H.
Partner: UNT Libraries Government Documents Department

Reactivity of biogenic manganese oxide for metal sequestration and photochemistry: Computational solid state physics study

Description: Many microbes, including both bacteria and fungi, produce manganese (Mn) oxides by oxidizing soluble Mn(II) to form insoluble Mn(IV) oxide minerals, a kinetically much faster process than abiotic oxidation. These biogenic Mn oxides drive the Mn cycle, coupling it with diverse biogeochemical cycles and determining the bioavailability of environmental contaminants, mainly through strong adsorption and redox reactions. This mini review introduces recent findings based on quantum mechanical density functional theory that reveal the detailed mechanisms of toxic metal adsorption at Mn oxide surfaces and the remarkable role of Mn vacancies in the photochemistry of these minerals.
Date: February 1, 2010
Creator: Kwon, K.D. & Sposito, G.
Partner: UNT Libraries Government Documents Department

Spatially fractionated microirradiation of normal CNS and gliosarcomas of the rat with synchrotron photons: Cell and tissue lesions; Raeumlich fraktionierte Mikrobestrahlung von normalem ZNS und Gliosarkomen der Ratte mit Synchrotron-Photonen: Zell- und Gewebelaesionen

Description: Rats were implanted intracerebrally with 9L gliosarcoma cells were used to experimentally determine the curative effectiveness of synchrotron radiation produced by the National Synchrotron Radiation Source. Radiation was delivered in beams with each ray 25 micrometers thick and arranged in an array of 4 mm corners. All experimental animals receiving the gliosarcoma cells and not treated died within four weeks. Treated animals surviving 113 days were sacrificed and their brains were examined histologically.
Date: December 31, 1995
Creator: Laissue, J.A.; Spanne, P.; Dilmanian, F.A.; Nawrocky, M.N.; Slatkin, D.N.; Joel, D.D. et al.
Partner: UNT Libraries Government Documents Department

Hanford/Tomsk reciprocal site visit: Plutonium agreement compliance talks

Description: The objective of the visit to Hanford Site was to: demonstrate equipment, technology, and methods for calculating Pu production, measuring integrated reactor power, and storing and safeguarding PuO{sub 2}; demonstrate the shutdown of Hanford production reactors; and foster openness and transparency of Hanford operations. The first day`s visit was an introduction to Hanford and a review of the history of the reactors. The second day consisted of discussions on the production reactors, reprocessing operations, and PuO{sub 2} storage. The group divided on the third day to tour facilities. Group A toured the N reactor, K-West reactor, K-West Basins, B reactor, and participated in a demonstration and discussion of reactor modeling computer codes. Group B toured the Hanford Pu Storage Facility, 200-East Area, N-cell (oxide loadout station), the Automated Storage Facility, and the Nondestructive Assay Measurement System. Group discussions were held during the last day of the visit, which included scheduling of a US visit to Russia.
Date: November 1, 1994
Creator: Libby, R.A.; Sorenson, R.; Six, D. & Schiegel, S.C.
Partner: UNT Libraries Government Documents Department

Computational study of one aspect of autoresonant accelerator

Description: Excitation and suppression of zero-frequency cyclotron waves on a relativistic electron beam in a parameter regime appropriate to autoresonant collective ion acceleration are examined through numerical simulation. The excitation mechanism considered is that of anode shorting, while suppression is achieved through a combination of nonadiabatic change in the guide magnetic field and the introduction of a finite radial velocity divergence in the beam. Some brief remarks are included concerning the effect of a scattered beam distribution.
Date: January 1, 1979
Creator: Shanahan, W.R.; Faehl, R.J. & Godfrey, B.B.
Partner: UNT Libraries Government Documents Department

Millimeter wave tokamak heating and current drive with a high power free electron laser

Description: Experiments on microwave generation using a free electron laser (FEL) have shown this to be an efficient way to generate millimeter wave power in short, intense pulses. Short pulse FEL's have several advantages that make them attractive for application to ECR heating of tokamak fusion reactors. This paper reports on plans made to demonstrate the technology at the Microwave Tokamak Experiment (MTX) Facility.
Date: January 1, 1987
Creator: Thomassen, K.I.
Partner: UNT Libraries Government Documents Department