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Recent Developments in Nuclear Waste Management in Canada

Description: This paper describes recent developments in the field of nuclear waste management in Canada with a focus on management of nuclear fuel waste. Of particular significance is the April 2001 tabling in the Canadian House of Commons of Bill C-27, An Act respecting the long-term management of nuclear fuel waste. At the time of finalizing this paper (January 15, 2002), Bill C-27 is in Third Reading in the House of Commons and is expected to move to the Senate in February. The Nuclear Fuel Waste Act is expected to come into force later in 2002. This Act requires the three nuclear utilities in Canada owning nuclear fuel waste to form a waste management organization and deposit funds into a segregated fund for nuclear fuel waste long-term management. The waste management organization is then required to perform a study of long-term management approaches for nuclear fuel waste and submit the study to the federal government within three years. The federal government will select an approach for implementation by the waste management organization. The paper discusses the activities that the nuclear fuel waste owners currently have underway to prepare for the formation of the waste management organization. As background, the paper reviews the status of interim storage of nuclear fuel waste in Canada, and describes previous initiatives related to the development of a national strategy for nuclear fuel waste long-term management.
Date: February 27, 2002
Creator: King, F.
Partner: UNT Libraries Government Documents Department

Design bases for U. S. Department of Energy storage basin

Description: Bases were developed for the conceptual design of a water basin to store 5000 MT of irradiated light water reactor fuel. The basin, which could be operational by 1983, is designed to receive over 2000 MT per year of spent fuel and to provide interim storage of US and some foreign fuel in support of U.S. policy of receiving and taking title to spent fuel rather than reprocessing this fuel. The bases for various design decisions are discussed.
Date: January 1, 1978
Creator: King, F.D.
Partner: UNT Libraries Government Documents Department

Comparison of alternative NPR fuel cycles

Description: It is likely that the proposals for the new heavy water production reactor will include at least one design incorporating a low-enriched uranium (LEU) fuel cycle while other designs will incorporate the traditional high enriched uranium (HEU) fuel. The LEU option would offer small advantages in reactor safety. On the other hand, as shown in this evaluation, using LEU rather than HEU in the new heavy water rector would decrease tritium production by 25% for comparable power-level reactors and would increase the annual throughput of total uranium about 10-fold. This would increase capital cost by $275 million and annual operating costs by $27 million, and would require several modifications to fuel fabrication, fuel reprocessing, and waste management facilities. Furthermore, the estimated four-fold increase in high-level waste from the LEU fuel cycle would run counter to DOE's long range goal of waste minimization. 18 refs., 6 figs., 7 tabs.
Date: April 1, 1989
Creator: King, F.D.
Partner: UNT Libraries Government Documents Department

Preparation and characterization of composite membrane for high temperature gas separation

Description: A new class of perm-selective inorganic membrane was developed by electroless deposition of palladium thin-film on a microporous {alpha}-alumina ceramic substrate ({phi}39 mm x 2 mm thickness, nominal pore size 150 nm and open porosity {approx} 42 %). The new membrane was characterized by Scanning Electron Micrography (SEM), Energy Dispersive X-ray Analysis (EDX) and conducting permeability experiments with hydrogen, helium, argon and carbon dioxide at temperatures from 473 K to 673 K and feed pressures from 136 kPa to 274 kPa. The results indicate that the membrane has both high permeability and selectivity for hydrogen. The hydrogen transport through the Pd-composite membrane closely followed Sievert's law. A theoretical model is presented to describe the performance of a single-stage permeation process. The model uses a unified mathematical formulation and calculation methods for two flow patterns (cocurrent and countercurrent) with two permeable components and a nonpermeable fraction in the feed and a sweep stream in the permeate. The countercurrent flow pattern is always better than the cocurrent flow pattern with respect to stage cut and membrane area. The effect of flow configuration decreases with increasing membrane selectivity or with decreasing permeate/feed ratio.
Date: March 26, 1998
Creator: Ilias, S. & King, F.G.
Partner: UNT Libraries Government Documents Department

Preparation and characterization of composite membrane for high temperature gas separation. Quarterly technical report, September 1--November 30, 1994

Description: To develop a new class of permselective inorganic membranes, the authors have identified electroless plating as a potential route to deposit a thin metal film on a porous substrate. Electroless plating is a controlled autocatalytic deposition of continuous film on the surface of a substrate by the interactions of a metal salt and a chemical reducing agent. This method can give thin films of metals, alloys and composites on both conducting and nonconducting surfaces. The objective of this project is to develop thin film palladium membranes for separation of hydrogen in high temperature applications. The authors plan to use electroless plating to deposit thin palladium films on microporous ceramic and silver substrates. They plan to characterize the membrane in terms of permeability and selectivity for gas separation. To accomplish the research objective, the project requires three tasks: Development of a process for composite membrane formation; Characterization of fabricated composite membrane; and Development of theoretical model for hydrogen gas separation. During this quarter, the authors attempted to measure the diffusivity and permeability of hydrogen gas through the palladium composite membrane. While running the diffusion measurements at elevated temperature and pressure, leakage of hydrogen was observed. This is a serious problem and it needs to be resolved. Currently, they are working on this problem. During this quarter, they also designed a diffusion cell to test thin-film palladium membrane in tubular structure. The diffusion cell is being fabricated and assembled by a local machine shop.
Date: December 31, 1994
Creator: Ilias, S. & King, F.G.
Partner: UNT Libraries Government Documents Department

Quantum Efficiency and Topography of Heated and Plasma-Cleaned Copper Photocathode Surfaces

Description: We present measurements of photoemission quantum efficiency (QE) for copper photocathodes heated and cleaned by low energy argon and hydrogen ion plasma. The QE and surface roughness parameters were measured before and after processing and surface chemical composition was tracked in-situ with x-ray photoelectron spectroscopy (XPS). Thermal annealing at 230 C was sufficient to improve the QE by 3-4 orders of magnitude, depending on the initial QE. Exposure to residual gas slowly reduced the QE but it was easily restored by argon ion cleaning for a few minutes. XPS showed that the annealing or ion bombardment removed surface water and hydrocarbons.
Date: August 4, 2005
Creator: Palmer, Dennis T.; PSD, /Titan; Kirby, R.E.; King, F.K. & /SLAC
Partner: UNT Libraries Government Documents Department

Residual Oxygen on Nb Heated to 500 C

Description: The superconducting accelerating cavities for the International Linear Collider will be constructed of high-residual resistivity ratio (RRR) niobium sheet. Excessive oxygen within the skin depth (several microns) will reduce the RRR and increase resistive losses. We measure the thickness of this oxide layer, following bakeout simulation, to be about 0.5 nm thick. The results suggest that this layer will very slowly disappear from the top five nm at 500 C.
Date: June 10, 2005
Creator: Kirby, R.; King, F. K. & Padamsee, H.
Partner: UNT Libraries Government Documents Department

Preparation and characterization of composite membrane for high temperature gas separation. Quarterly technical report, December 1, 1996--February 28, 1997

Description: To develop a new class of permselective inorganic membranes, the authors have identified electroless plating as a potential route to deposit a thin metal film on a porous substrate. Electroless plating is a controlled autocatalytic deposition of continuous film on the surface of a substrate by the interactions of a metal salt and a chemical reducing agent. This method can give thin films of metals, alloys and composites on both conducting and nonconducting surfaces. The objective of this project is to develop thin film palladium membranes for separation of hydrogen in high temperature applications. The authors plan to use electroless plating to deposit thin palladium films on microporous ceramic and silver substrates. They plan to characterize the membrane in terms of permeability and selectivity for gas separation. To accomplish the research objective, the project requires three tasks: (1) development of a process for composite membrane formation; (2) characterization of fabricated composite membrane; and (3) development of theoretical model for hydrogen gas separation. During this quarter they extended their single-staged complete-mixing and cross-flow models to design a Two-Unit-Series (TUS), a Two-Stage Counter-Current Recycle Membrane Cascade (CRMC) and a Five-Stage CRMC arrangement. These designs have been used to study the performance of membrane modules for the separation of hydrogen through Palladium-ceramic composite membranes. The results show that for high-selective membrane, the effect of flow arrangement is of no consequence. Multi-staged cascading significantly improve the product purity and product separation.
Date: December 31, 1997
Creator: Ilias, S. & King, F.G.
Partner: UNT Libraries Government Documents Department

Continued development of an atmospheric monitoring mass spectrometry system - task 2.2. Topical report, January 1, 1995--December 31, 1995

Description: The objective of this project was the development of a mass spectrometric methodology applicable to the field determination of Volatile Organic Compounds (VOC`s), such as BTEX components (Benzene, Toluene, Ethylbenzene, and Xylenes). A combination of chemical ionization, selective ion storage, and tandem mass spectrometry was planned to be employed with an ion trap mass spectrometry system. The Gas Chromatography Mass Spectrometry (GC-MS) interface on the ion trap system was modified to permit direct atmospheric monitoring. Through the use of tandem mass spectrometry methods the need for chromatographic separation would be eliminated reducing the overall size and complexity of the system.
Date: December 31, 1998
Creator: King, F.L.
Partner: UNT Libraries Government Documents Department

Preparation and Char Characterization of Composite Membrane for High Temperature Gas Separation.

Description: A palladium-ceramic composite membrane was developed by electroless deposition of palladium on microporous ceramic substrate. By measuring the permeation characteristics of pure and mixed gases, it was found that the new membrane has a very high permeability and selectivity for hydrogen. During this reporting period, a concurrent flow model for a membrane module was developed to study the performance of palladium-ceramic composite membranes for hydrogen separation in terms of product purity under various operating conditions. The model neglects mass transfer resistance but it was found that the difference between the predicted and actual hydrogen composition was less than 12%.
Date: July 31, 1997
Creator: Illias, S. & King, F.G.
Partner: UNT Libraries Government Documents Department

Separation of hydrogen using thin film palladium-ceramic composite membrane

Description: The primary objective of this study was to prepare and characterize a hydrogen permselective palladium-ceramic composite membrane for high temperature gas separations and catalytic membrane reactors. Electroless plating method was used as a potential route to deposit a thin palladium film on microporous ceramic substrate. The objectives of the work presented here were to characterize the new Pd-ceramic composite membrane by SEM and EDX analysis and to carry out fundamental permeability measurements of the membrane at elevated temperatures and pressures. The potential application of membranes in high temperature gas separation and reactor technology have been recognized by many investigators. In the coal gasification process, the exit gases are normally hydrogen, carbon monoxide, carbon dioxide, hydrogen sulfide, and water vapor. The objective is to obtain hydrogen from this gas mixture.
Date: November 1, 1995
Creator: Ilias, S.; King, F.G.; Su, N. & Udo-Aka, U.I.
Partner: UNT Libraries Government Documents Department

The Relationship Between Answers on Individual Items of the California Test of Personality and Position and in the Group as Measured by the North Texas Sociometric Scale

Description: First of all an attempt is made to determine whether or not the individual items on the California Test of Personality will successfully differentiate between persons of low and high peer acceptance. Secondly, research of this nature would establish a basis for construction of a self-rating test which would measure peer acceptance, or at least measure traits which presumably make for peer acceptance, in situations where it would not be possible to administer the regular sociometric scales.
Date: 1950
Creator: King, F. J.
Partner: UNT Libraries

Irrigation in Humid Climates

Description: Report discussing and promoting irrigation practices in the eastern United States, which, although its climate is humid, does not have sufficient soil moisture in drier seasons to produce a maximum crop yield.
Date: 1896
Creator: King, F. H. (Franklin Hiram), 1848-1911
Partner: UNT Libraries Government Documents Department

Test of the electronic structure of Fe(100) by absorbed current spectroscopy

Description: The absorbed electron current for a clean Fe(100) surface as a function of energy rises step-like at the vacuum-energy cutoff with an absorption close to 1. The smooth decrease of absorbed current at higher electron energy due to secondary electron emission is superimposed by a considerable amount of fine structure, the amplitude of which decreases with increasing energy. These features are found in good agreement with the results of a calculation of the elastic part of the electron reflection coefficient. Further, they are compared with the ferromagnetic electronic bulk bandstructure calculated above the vacuum energy. From the comparison with the experimental data, the energy dependence of the real and imaginary parts of the inner potential is determined.
Date: October 1, 1984
Creator: Kisker, E.; Kirby, R.E.; Garwin, E.L. & King, F.K.
Partner: UNT Libraries Government Documents Department

Surface properties of metal-nitride and metal-carbide films deposited on Nb for RF superconductivity

Description: Various effects occur which can prevent attainment of the high Q's and/or the high gradient fields necessary for the operation of rf superconducting cavities. One of these effects, multipactor, both causes the cavity to detune during filling due to resonant secondary electron emission at the cavity walls, and lowers the Q by dissipative processes. TiN deposited onto the high field regions of room temperature Al cavities has been used at SLAC to successfully reduce multipactor in the past. We have therefore studied TiN and its companion materials, NbN, NbC, and TiC, all on Nb substrates under several realistic conditions: (1) as deposited, (2) exposed to air, and (3) 1 keV electron-bombarded. The studied films (up to 14 nm thickness) were sputter deposited onto sputter-cleaned Nb substrates. Results indicate that the materials tested gave substantially the same results. The maximum secondary electron yields for as-deposited films was about 1.0 to 1.2. These yields rose to greater than 1.5 upon air-exposure and were reduced to nearly the pre-oxidized values after electron bombardment (about 3 x 10/sup 17/ electrons-cm/sup -2/ in the case of NbN and NbC). XPS analysis showed that the oxides (e.g. TiO/sub 2/ in the case of TiN films) formed during air exposure were only slightly reduced (converted to lower oxides) by the electron beam exposure. AES showed a slight reduction in the surface O concentration following beam exposure. The results indicate that any of these films would be poor choices if simply deposited and exposed to air, but, in fact, the in-situ electron bombardment which occurs in cavities serves to reduce the effective secondary electron yield and thereby causes a substantial reduction in multipacting.
Date: September 1, 1983
Creator: Garwin, E.L.; King, F.K.; Kirby, R.E. & Aita, O.
Partner: UNT Libraries Government Documents Department

The Effect of Gas Ion Bombardment on the Secondary Electron Yield of TiN, TiCN and TiZrV Coatings For Suppressing Collective Electron Effects in Storage Rings

Description: In many accelerator storage rings running positively charged beams, ionization of residual gas and secondary electron emission (SEE) in the beam pipe will give rise to an electron cloud which can cause beam blow-up or loss of the circulating beam. A preventative measure that suppresses electron cloud formation is to ensure that the vacuum wall has a low secondary emission yield (SEY). The SEY of thin films of TiN, sputter deposited Non-Evaporable Getters and a novel TiCN alloy were measured under a variety of conditions, including the effect of re-contamination from residual gas.
Date: January 25, 2006
Creator: Le Pimpec, F.; /PSI, Villigen; Kirby, R.E.; King, F.K.; Pivi, M. & /SLAC
Partner: UNT Libraries Government Documents Department

In-Situ Cleaning of Metal Cathodes using a Hydrogen Ion Beam

Description: Metal photocathodes are commonly used in high-field RF guns because they are robust, straightforward to implement and tolerate relatively poor vacuum compared to semi-conductor cathodes. However these cathodes have low quantum efficiency (QE) even at UV wavelengths, and still require some form of cleaning after installation in the gun. A commonly used process for improving the QE is laser cleaning. In this technique the UV drive laser is focused to a small diameter close to the metal's damage threshold and then moved across the surface to remove contaminants. This method does improve the QE, but can produce non-uniform emission and potentially damage the cathode. Ideally an alternative process which produces an atomically clean, but unaltered surface is needed. In this paper we explore using a hydrogen ion (H-ion) beam to clean a copper cathode. We describe QE measurements over the wavelength range of interest as a function of integrated exposure to an H-ion beam. We also describe the data analysis to obtain the work function and derive a formula of the QE for metal cathodes. Our measured work function for the cleaned sample is in good agreement with published values, and the theoretical QE as a function of photon wavelength is in excellent agreement with the cleaned copper experimental results. Finally, we propose an in-situ installation of an H-ion gun compatible with existing s-band RF guns.
Date: March 29, 2006
Creator: Dowell, D.H.; King, F.K.; Kirby, R.E.; Schmerge, J.F. & /SLAC
Partner: UNT Libraries Government Documents Department

In-Situ Cleaning of Metal Cathodes Using a Hydrogen Ion Beam

Description: Improving and maintaining the quantum efficiency (QE) of a metal photocathode in an s-band RF gun requires a process for cleaning the surface. In this type of gun, the cathode is typically installed and the system is vacuum baked to {approx}200 degrees C. If the QE is too low, the cathode is usually cleaned with the UV-drive laser. While laser cleaning does increase the cathode QE, it requires fluences close to the damage threshold and rastering the small diameter beam, both of which can produce nonuniform electron emission and potentially damage the cathode. This paper investigates the efficacy of a low energy hydrogen ion beam to produce high-QE metal cathodes. Measurements of the QE vs. wavelength, surface contaminants using x-ray photoelectron spectroscopy and surface roughness were performed on a copper sample, and the results showed a significant increase in QE after cleaning with a 1keV hydrogen ion beam. The H-ion beam cleaned an area approximately 1cm in diameter and had no effect on the surface roughness while significantly increasing the QE. These results and a comparison with theory as well as a scheme for installing an H-ion cleaner on an s-band gun are presented.
Date: September 1, 2005
Creator: Dowell, D.H.; King, F.K.; Kirby, R.E.; Schmerge, J.F. & /SLAC
Partner: UNT Libraries Government Documents Department

Comparison Between H-Ion and Heat Cleaning of Cu-Metal Cathodes

Description: Understanding the quantum efficiency (QE) of a metal photocathode in an s-band RF gun is important to limit the drive laser energy requirement and provide the best quality electron beam. Systematic measurements of the qe vs. wavelength for varying surface contamination have been performed on copper samples using x-ray photoelectron spectroscopy (XPS). The sample is first cleaned to the theoretical limit of QE using a 1 keV hydrogen ion beam. The H-ion beam cleans an area approximately 1cm in diameter and has no effect on the surface roughness while removing essentially all contaminants and lowering the work function to 4.3eV[1]. The sample is then exposed to atmospheric contaminants (nitrogen and oxygen) and measured again with XPS to determine the degree of contamination and their effect on the QE. These results and comparison with theory are presented.
Date: August 18, 2006
Creator: Dowell, D.H.; King, F.K.; Kirby, R.E.; /SLAC; Schmerge, J.F. & /SLAC, SSRL
Partner: UNT Libraries Government Documents Department

Separation of Hydrogen Using an Electroless Deposited Thin-Film Palladium-Ceramic Composite Membrane

Description: The primary objective of this project was to prepare and characterize a hydrogen permselective palladium-ceramic composite membrane for high temperature gas separations and catalytic membrane reactors. Electroless plating method was used to deposit a thin palladium film on microporous ceramic substrate. The objective of this paper is to discuss the preparation and characterization of a thin-film palladium-ceramic composite membrane for selective separation of hydrogen at elevated temperatures and pressures. In this paper, we also present a model to describe the hydrogen transport through the palladium-ceramic composite membrane in a cocurrent flow configuration.
Date: December 31, 1996
Creator: Ilias, S.; King, F.G.; Fan, Ting-Fang & Roy, S.
Partner: UNT Libraries Government Documents Department

RF superconducting properties of thin films on niobium

Description: We are investigating the RF properties of thin films of materials which are known to have low secondary emission coefficients, such as NbC, NbN and TiN. Preliminary measurements on the latter material have been performed by depositing a 15 nm film on parts of a doubly re-entrant Nb cavity designed to favor electron multipacting which, in the uncoated cavity, occurs copiously between the posts' tips. The measurements performed with TiN films sputtered onto Nb indicate that the RF current losses are increased by the presence of the films while the dielectric losses are negligible, within the measurement sensitivity of the system. The electron multipacting cannot be excited between the posts coated with the material tested.
Date: March 1, 1983
Creator: Campisi, I.E.; Deruyter, H.; Farkas, Z.D.; Garwin, E.L.; Hogg, H.A.; King, F. et al.
Partner: UNT Libraries Government Documents Department

Sharp Reduction of the Secondary Electron Emission Yield from Grooved Surfaces

Description: The effect of an artificially-enhanced rough surface on the secondary electron emission yield (SEY) was investigated both theoretically and experimentally. Analytical studies on triangular and rectangular grooved surfaces show the connection between the characteristic parameters of a given geometry to the SEY reduction. The effect of a strong magnetic field is also discussed. SEY of grooved samples have been measured and the results agree with Monte-Carlo simulations.
Date: November 28, 2007
Creator: Pivi, M.T.F.; King, F.K.; Kirby, R.E.; Ruabenheimer, T.O.; Stupakov, G.; /SLAC et al.
Partner: UNT Libraries Government Documents Department