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Equation of State measurements of hydrogen isotopes on Nova

Description: High intensity lasers can be used to perform measurements of materials at extremely high pressures if certain experimental issues can be overcome. We have addressed those issues and used the Nova laser to shock-compress liquid deuterium and obtain measurements of density and pressure on the principal Hugoniot at pressures from 300 kbar to more than 2 Mbar. The data are compared with a number of equation of state models. The data indicate that the effect of molecular dissociation of the deuterium into a monatomic phase may have a significant impact on the equation of state near 1 Mbar.
Date: November 1, 1997
Creator: Collins, G. W., LLNL
Partner: UNT Libraries Government Documents Department

Cryogenic Distillation: a Fuel Enrichment System for Near-Term Tokamak-Type D-T Fusion Reactors

Description: The successful operation and economic viability of deuterium-tritium- (D-T-) fueled tokamak-type commercial power fusion reactors will depend to a large extent on the development of reliable tritium-containment and fuel-recycle systems. Of the many operating steps in the fuel recycle scheme, separation or enrichment of the isotropic species of hydrogen by cryogenic distillation is one of the most important. A parametric investigation was carried out to study the effects of the various operating conditions and the composition of the spent fuel on the degree of separation. A computer program was developed for the design and analysis of a system of interconnected distillation columns for isotopic separation such that the requirements of near-term D-T-fueled reactors are met. The analytical results show that a distillation cascade consisting of four columns is capable of reprocessing spent fuel varying over a wide range of compositions to yield reinjection-grade fuel with essentially unlimited D/T ratio.
Date: February 1980
Creator: Misra, B. & Davis, J. F.
Partner: UNT Libraries Government Documents Department

COMMENTS ON ANOMALOUS EFFECTS IN CHARGING OF PD POWDERS WITH HIGH DENSITY HYDROGEN ISOTOPES

Description: In Kitamura, et al, Pd-containing materials are exposed to isotopes of hydrogen and anomalous results obtained. These are claimed to be a replication of another experiment conducted by Arata and Zhang. Erroneous basic assumptions are pointed out herein that alter the derived conclusions significantly. The final conclusion is that the reported results are likely normal chemistry combined with noise. Thus the claim to have proven that cold fusion is occurring in these systems is both premature and unlikely.
Date: October 1, 2009
Creator: Shanahan, K.
Partner: UNT Libraries Government Documents Department

Raman spectroscopic and mass spectrometric investigations of the hydrogen isotopes and isotopically labelled methane

Description: Suitable analytical methods must be tested and developed for monitoring the individual process steps within the fuel cycle of a fusion reactor and for tritium accountability. The utility of laser-Raman spectroscopy accompanied by mass spectrometry with an Omegatron was investigated using the analysis of all hydrogen isotopes and isotopically labeled methanes as an example. The Omegatron is useful for analyzing all hydrogen isotopes mixed with the stable helium isotopes. The application of this mass spectrometer were demonstrated by analyzing mixtures of deuterated methanes. In addition, it was employed to study the radiochemical Witzbach exchange reaction between tritium and methanes. A laser-Raman spectrometer was designed for analysis of tritium-containing gases and was built from individual components. A tritium-compatible, metal-sealed Raman cuvette having windows with good optical properties and additional means for measuring the stray light was first used successfully in this work. The Raman spectra of the hydrogen isotopes were acquired in the pure rotation mode and in the rotation-vibration mode and were used for on. The deuterated methanes were measured by Raman spectroscopy, the wavenumbers determined were assigned to the corresponding vibrations, and the wavenumbers for the rotational fine-structure were summarized in tables. The fundamental Vibrations of the deuterated methanes produced Witzbach reactions were detected and assigned. The fundamental vibrations of the molecules were obtained with Raman spectroscopy for the first time in this work. The @-Raman spectrometer assembled is well suited for the analysis of tritium- containing gases and is practical in combination with mass spectrometry using an Omegatron, for studying gases used in fusion.
Date: February 24, 1997
Creator: Jewett, J.R., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department

Tritium Separation Using Metal Hydrides

Description: This paper discusses some of the metal hydride and intermetallic compounds which readily absorb the hydrogen gas by a simple contact to form metal hydrides. Metal hydrides have several important properties for the hydrogen isotope separation.
Date: March 9, 2001
Creator: Lee, M.W.
Partner: UNT Libraries Government Documents Department

A new global hydrogen equation of state model

Description: Simple statistical mechanics models have been assembled into a wide-range equation of state for the hydrogen isotopes. The solid is represented by an Einstein-Grtineisen model delimited by a Lindemann melting curve. The fluid is represented by an ideal gas plus a soft-sphere fluid configurational term. Dissociation and ionization are approximated by modifying the ideal gas chemical-equilibrium formulation. The T = 0 isotherm and dissociation models have been fitted to new diamond-anvil isotherm and laser-generated shock data. The main limitation of the model is in ionization at high compression.
Date: June 25, 1999
Creator: Young, D
Partner: UNT Libraries Government Documents Department

Tritium-Management Requirements for D-T Fusion Reactors (ETF, INTOR, FED)

Description: The successful operation of D-T fusion reactors will depend on the development of safe and reliable tritium-containment and fuel-recycle systems. The tritium handling requirements for D-T reactors were analyzed. The reactor facility was then designed from the viewpoint of tritium management. Recovery scenarios after a tritium release were generated to show the relative importance of various scenarios. A fusion-reactor tritium facility was designed which would be appropriate for all types of plants from the Engineering Test Facility (ETF), the International Tokamak Reactor (INTOR), and the Fusion Engineering Device (FED) to the full-scale power plant epitomized by the STARFIRE design.
Date: October 1981
Creator: Finn, P. A.; Clemmer, Robert G. & Misra, B.
Partner: UNT Libraries Government Documents Department

Deuterium Retention in NSTX with Lithium Conditioning

Description: High (≈ 90%) deuterium retention was observed in NSTX gas balance measurements both withand without lithiumization of the carbon plasma facing components. The gas retained in ohmic discharges was measured by comparing the vessel pressure rise after a discharge to that of a gasonly pulse with the pumping valves closed. For neutral beam heated discharges the gas input and gas pumped by the NB cryopanels were tracked. The discharges were followed by outgassing of deuterium that reduced the retention. The relationship between retention and surface chemistry was explored with a new plasma-material interface probe connected to an in-vacuo surface science station that exposed four material samples to the plasma. XPS and TDS analysis showed that the binding of D atoms is fundamentally changed by lithium - in particular atoms are weakly bonded in regions near lithium atoms bound to either oxygen or the carbon matrix.
Date: June 2, 2010
Creator: C.H. Skinner, J.P. Allain, W. Blanchard, H.W. Kugel, R. Maingi, L. Roquemore, V. Soukhanovskii, C.N. Taylor
Partner: UNT Libraries Government Documents Department

3HE RECOVERY FROM A TRITIUM-AGED LANA75 SAMPLE

Description: {sup 3}He recovery is a topic of recent interest. One potential recovery source is from metal hydride materials once used to store tritium, as the decay product, {sup 3}He, is primarily trapped in the metal lattice, usually in bubbles, with such materials. In 2001, a Tritium Exposure Program (TEP) sample known as LANA75-SP1 was retired and the material was removed from the test cell and stored. Subsequently scoping temperature programmed desorption (TPD) experiments were conducted on that material to see what it might take to drive out He and residual H isotopes (the heel). Two experiments consisted of heating the sample in the presence of an excess of tin (the so-called Sn fusion experiment), and one was a simple TPD with no additives. Prior data on the so-called '21-month bed' material in the 1980's had produced {approx}21 cc of gas per gram of a LANA30 material (LaNi4.7Al0.3), with approximately 67% of that being {sup 3}He and the rest being D{sub 2} (Fig.3). However, the material had to be heated in excess of 850 C to obtain that level. Heating to less produced approximately half that amount of gas. The data also showed that {sup 3}He was released at different temperatures than the residual hydrogen isotopes. Unfortunately this implies full {sup 3}He recovery will be a difficult process. Therefore, it seemed advisable to attempt to extract as much information from the 3 scoping experiments from 2001-2 as possible.
Date: December 1, 2010
Creator: Shanahan, K.
Partner: UNT Libraries Government Documents Department

ENCAPSULATION OF PALLADIUM IN POROUS WALL HOLLOW GLASS MICROSPHERES

Description: A new encapsulation method was investigated in an attempt to develop an improved palladium packing material for hydrogen isotope separation. Porous wall hollow glass microspheres (PWHGMs) were produced by using a flame former, heat treating and acid leaching. The PWHGMs were then filled with palladium salt using a soak-and-dry process. The palladium salt was reduced at high temperature to leave palladium inside the microspheres.
Date: April 9, 2008
Creator: Heung, L.; George Wicks, G. & Ray Schumacher, R.
Partner: UNT Libraries Government Documents Department

Recent high-speed ballistics experiments at ORNL

Description: Oak Ridge National Laboratory (ORNL) has been developing pellet injectors for plasma fueling experiments on magnetic confinement devices for almost 20 years. With these devices, pellets (1 to 8 mm in diameter) composed of hydrogen isotopes are formed (at temperatures <20 K) and typically accelerated to speeds of {approximately} 1.0 to 2.0 km/s for injection into plasmas of experimental fusion devices. A variety of pellet injector designs have been developed at ORNL, including repeating pneumatic injectors (single- and multiple-barrel light gas guns) that can inject up to hundreds of pellets for long-pulse plasma operation. The repeating pneumatic injectors are of particular importance because long-pulse fueling is required for present large experimental fusion devices, with steady-state operation the objective for future fusion reactors. In this paper, recent advancements in the development of repeating pneumatic injectors are described, including (1) a small-bore (1.8-mm), high-firing-rate (10-Hz) version of a single-stage light gas gun; (2) a repeating single-stage light gas gun for 8-mm-diam tritium pellets; (3) a repeating two-stage light gas gun for operation at higher pellet velocities; and (4) a steady-state hydrogen extruder feed system.
Date: December 31, 1994
Creator: Combs, S.K.; Gouge, M.J.; Baylor, L.R.; Fisher, P.W.; Foster, C.A.; Foust, C.R. et al.
Partner: UNT Libraries Government Documents Department

Advanced Mass Spectrometers for Hydrogen Isotope Analyses

Description: This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.
Date: August 1, 2001
Creator: Chastagner, P.
Partner: UNT Libraries Government Documents Department

Diffuse II -- A hydrogen isotope diffusion and trapping simulation program upgrade

Description: Diffuse is a finite difference computer program which may be used to calculate the one-dimensional diffusion and trapping of atoms in a host material under general initial, source, and boundary conditions. Diffuse was originally written in Fortran prior to 1980, and rewritten in 1983 in order to run on the Sandia Cray computers in use through the early 1990's. When the mainframe computers were retired, the Gas Transfer System (GM) Development Department ported the code to the PC platform, where it ran as a simple console application. All graphical output was lost during this port. GM code developers have completed an upgrade that provides a Windows 95/NT Diffuse application and restores all of the original graphical output. This upgrade is called Diffuse II version 1.0. This report serves both as a users manual for Diffuse II version 1.0 and as a general software development reference.
Date: November 1, 1998
Creator: Hardwick, M. F. & Robinson, S. L.
Partner: UNT Libraries Government Documents Department

Exotic atoms. Technical progress report, February 1, 1995--January 31, 1996

Description: A variety of hydrogen isotopic mixtures form solid targets to produce muonic hydrogen isotope atoms. The method relies on muon capture by a proton and transfer of the muon from the proton to a deuteron or a triton. The resulting muonic deuterium or muonic tritium will not immediately thermalize because of the very low elastic cross sections of the Ramsauer-Townsend effect, and are emitted from the surface of the layer and escape into a vacuum region. A second solid hydrogen isotopic target is produced downstream on which the muonic hydrogen atom can react and the time of flight measured.
Date: November 1, 1995
Creator: Kunselman, R.
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M : Report for 1989

Description: The results of the environmental monitoring program conducted at Site A/Plot M in the Palos Park Forest Preserve area for CY 1989 are presented. The monitoring program is the ongoing remedial action that resulted from the 1976-1978 radiological characterization of the site. That study had determined that very low levels of hydrogen-3 (as tritiated water) migrated from the burial ground and was present in two nearby hand-pumped picnic wells. The current program consists of sample collection and analysis of air, surface and subsurface water, and bottom sediment.
Date: April 1990
Creator: Golchert, N. W.
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M : Report for 1990

Description: The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for CY 1990 are presented. The surveillance program is the ongoing remedial action that resulted from the 1976-1978 radiological characterization of the site.
Date: May 1991
Creator: Golchert, N. W.
Partner: UNT Libraries Government Documents Department

TSOAK-M1 : a Computer Code to Determine Tritium Reaction/Adsorption/Release Parameters from Experimental Results of Air-Detritiation Tests

Description: A computer code has been developed which permits the determination of tritium reaction (T2 to HTO)/adsorption/release and instrument correction parameters from enclosure (building) - detritiation test data. The code is based on a simplified model which treats each parameter as a normalized time-independent constant throughout the data-unfolding steps. Because of the complicated four-dimensional mathematical surface generated by the resulting differential equation system, occasional local-minima effects are observed, but these effects can be overcome in most instances by selecting a series of trial guesses for the initial parameter values and observing the reproducibility of final parameter values for cases where the best overall fit to experimental data is achieved. The code was then used to analyze existing small-cubicle test data with good success, and the resulting normalized parameters were employed to evaluate hypothetical reactor-building detritiation scenarios. It was concluded from the latter evaluation that the complications associated with moisture formation, adsorption, and release, particularly in terms of extended cleanup times, may not be as great as was previously thought. It is recommended that the validity of the TSOAK-M1 model be tested using data from detritiation tests conducted on large experimental enclosures (5 to 10 cu cm) and, if possible, actual facility buildings.
Date: 1979?
Creator: Land, Robert H.; Land, Robert H.; Maroni, V. A. & Minkoff, Michael
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M : Report for 1991

Description: The results of the environmental surveillance program conducted at Site A/plot M in the Palos Forest Preserve area for CY 1991 are presented. The surveillance program is the ongoing remedial action that resulted from the 1976-1978 radiological characterization of the site. That study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells. The current program consists of sample collection and analysis of air, surface and subsurface water, and bottom sediment.
Date: May 1992
Creator: Golchert, N. W.
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M : Report for 1992

Description: The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for CY 1992 are presented. The surveillance program is the ongoing remedial action that resulted from the 1976-1978 radiological characterization of the site. That study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells. The current program consists of sample collection and analysis of air, surface and subsurface water, and bottom sediment.
Date: May 1993
Creator: Golchert, N. W.
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M : Report for 1993

Description: The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for CY 1993 are presented. The surveillance program is the ongoing remedial action that resulted from the 1976-1978 radiological characterization of the site. That study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells.
Date: May 1994
Creator: Golchert, N. W.
Partner: UNT Libraries Government Documents Department