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Major issues associated with DOE commercial recycling initiatives (open access)

Major issues associated with DOE commercial recycling initiatives

Major initiatives are underway within DOE to recycle large volumes of scrap material generated during cleanup of the DOE Weapons Complex. These recycling initiatives are driven not only by the desire to conserve natural resources, but also by the recognition that shallow level burial is not a politically acceptable option. The Fernald facility is in the vanguard of a number of major DOE recycling efforts. These early efforts have brought issues to light that can have a major impact on the ability of Fernald and other major DOE sites to expand recycling efforts in the future. Some of these issues are; secondary waste deposition, title to material and radioactive contaminants, mixed waste generated during recycling, special nuclear material possession limits, cost benefit, transportation of waste to processing facilities, release criteria, and uses for beneficially reused products.
Date: July 27, 1994
Creator: Motl, G. P.; Burns, D. D. & Rast, D. M.
System: The UNT Digital Library
Projection Gas Immersion Laser Doping (P-GILD): A resistless, nanosecond thermal doping/diffusion technology (open access)

Projection Gas Immersion Laser Doping (P-GILD): A resistless, nanosecond thermal doping/diffusion technology

Projection Gas Immersion Laser Doping (P-GILD) is an innovative doping process that utilizes finely patterned excimer laser light to thermally process discreet regions within an integrated circuit. By reducing the total temperature cycle to nanoseconds and localizing the thermal energy in depth and area, P-GILD fundamentally changes the junction formation process. This paper first reviews the general characteristics of the P-GILD process and equipment. Two variations of the technique, melt and non-melt, and their resulting junction characteristics are then described in detail. The combination of the two laser processes along with the simplification that a resistless technology brings to the process sequence, enables efficient fabrication of impurity profiles that are ideal for a wide array of transistor applications.
Date: July 27, 1994
Creator: Weiner, K. H.
System: The UNT Digital Library
Quarter-scale close-in blast-loading experiments in support of the planned contained firing facility (open access)

Quarter-scale close-in blast-loading experiments in support of the planned contained firing facility

In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory is proposing to construct a 60-kg firing chamber to provide blast-effects containment for most of its open-air, high-explosive, firing operations. Even though the Laboratory`s operations are within current environmental limits, containment of the blast effects and hazardous debris will drastically reduce emissions to the environment and minimize the generated hazardous waste. One of the main design considerations is the extremely close-in (Z = 0.66 ft/lb{sup l/3}) blast loading on the reinforced concrete ff the chamber. Historically, floor damage due to close-in loading has been a common problem for other blast chambers within the US Department of Energy and Department of Defense (DOE/DoD). Blast-effects testing and computer analysis were conducted on a replica quarter-scale model of the preliminary floor design. Nineteen blast tests ranging from scaled distances of 1.14 ft/lb{sup l/3} (25%) to 0.57ft/lb{sup 1/3} (200%) were performed on the strain-gaged floor model. In response to predicted and measured failures at the 25% level, various state-of-the-art blast attenuation systems were quickly developed and tested. The most effective blast-attenuation system provided a significant improvement by reducing the measured floor stresses to acceptable levels while minimizing, by its reusability, the impact on …
Date: July 27, 1994
Creator: Pastrnak, J. W.; Baker, C. F. & Simmons, L. F.
System: The UNT Digital Library
Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}} (open access)

Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}}

We report on a search for flavor-changing neutral current decays of B mesons into {mu}{mu}K{sup {plus_minus}} using data obtained in the Collider Detector at Fermilab (CDF) 1992--1993 data taking run. To reduce the amount of background in our data we use precise tracking information from the CDF silicon vertex detector to pinpoint the location of the decay vertex of the B candidate, and accept only events which have a large decay time. We compare this data to a B meson signal obtained in a similar fashion, but where the muon pears originate from {psi} decays, and calculate the relative branching ratios. In absence of any indication of flavor-changing neutral current decay we set an upper limit on the branching ratio of 3.2 {times} 10{sup {minus}1}, which is consistent with Standard Model expectations but leaves little room for non-standard physics.
Date: May 27, 1994
Creator: CDF Collaboration
System: The UNT Digital Library
MIC damage in a water coolant header for remote process equipment (open access)

MIC damage in a water coolant header for remote process equipment

Stainless steel water piping used to supply coolant for remote chemical separations equipment developed leaks during low flow conditions resulting from an extended interruption of operations. All the leaks occurred at welds in the bottom zone of the pipe, which was blanketed with silt deposits from the unfiltered well water used for cooling. Ultrasonic, radiographic, and metallographic examinations of leak sites revealed worm hole pitting adjacent to the welds. Seepage at the penetrations was strongly acidic and resulted in corrosion on the external pipe surfaces beneath brown crusty deposits which had developed. Analyses of the water and deposits suggest a strong propensity toward microbiologically influenced corrosion (MIC) and fouling.
Date: September 27, 1994
Creator: Jenkins, C. F.
System: The UNT Digital Library
The Hanford Site Tank Waste Remediation System: An update (open access)

The Hanford Site Tank Waste Remediation System: An update

The U.S. Department of Energy`s Hanford Site, located in southeastern Washington State, has the most diverse and largest amount of highly radioactive waste in the United States. High-level radioactive waste has been stored in large underground tanks since 1944. Approximately 230,000 m{sup 3} (61 Mgal) of caustic liquids, slurries, saltcakes, and sludges have {sup 137}Cs accumulated in 177 tanks. In addition, significant amounts of {sup 90}Sr and were removed from the tank waste, converted to salts, doubly encapsulated in metal containers., and stored in water basins. A Tank Waste Remediation System Program was established by the U.S. Department of Energy in 1991 to safely manage and immobilize these wastes in anticipation of permanent disposal of the high-level waste fraction in a geologic repository. Since 1991, progress has been made resolving waste tank safety issues, upgrading Tank Farm facilities and operations, and developing a new strategy for retrieving, treating, and immobilizing the waste for disposal.
Date: January 27, 1994
Creator: Alumkal, W. T.; Babad, H.; Harmon, H. D. & Wodrich, D. D.
System: The UNT Digital Library
Fabrication options for depleted uranium components in shielded containers (open access)

Fabrication options for depleted uranium components in shielded containers

Depleted uranium (DU) is an attractive material for the gamma-shielding components in containers designed for the storage, transport, and disposal of high-level radioactive wastes or spent nuclear fuel. The size and weight of these components present fabrication challenges. A broad range of technical expertise, capabilities, and facilities for uranium manufacturing and technology development exist at the Department of Energy laboratories and production facilities and within commercial industry. Several cast and wrought processes are available to fabricate the DU components. Integration of the DU fabrication capabilities and physical limitations for handling the DU components into the early design phase will ensure a fabricable product.
Date: January 27, 1994
Creator: Derrington, S. B.; Thompson, J. E. & Coates, C. W.
System: The UNT Digital Library
Warm formability of aluminum-magnesium alloys (open access)

Warm formability of aluminum-magnesium alloys

Manufacturers have become increasingly interested in near-net-shape forming of aluminum alloys as a means to reduce production costs and the weight of aircraft and automotive structures. To achieve the ductilities required for this process, we have examined extended ductility of Al-Mg alloys in the warm forming, or Class I creep, regime. We have studied a high-purity, binary alloy of Al-2.8Mg and ternary alloys of Al-xMg-0.5Mn with Mg concentrations from 1.0 to 6.6 wt. %. Tensile tests, including strain rates-change tests, have been performed with these materials at temperatures of 300 and 400C over a range 10{sup {minus}4} to 2 {times} 10{sup {minus}2} s{sup {minus}1}. A maximum tensile failure strain of 325% for the binary alloy and a maximum of 125% in the ternary alloys have been measured. The experimental results have been used to evaluate the effects of solute concentration, microstructure, temperature, and strain rate on flow stress ({sigma}), elongation to failure (e{sub f}), and strain-rate sensitivity (m) of these alloys.
Date: May 27, 1994
Creator: Taleff, E. M.; Henshall, G. A.; Lesuer, D. R. & Nieh, T. G.
System: The UNT Digital Library
A computerized welder qualification record and tracking system (open access)

A computerized welder qualification record and tracking system

Accurately tracking welder qualification and assigning welders to jobs for which they are qualified is becoming more important as customers increasingly demand improved quality and conformance to industry standards. A computerized welder qualification records and tracking system (WPQ) was developed at the Oak Ridge Y-12 Plant to assist the user in this process. The system enables the user to consistently generate welder qualification records with minimal effort and increased accuracy, relate the welder qualification limits with the limits of the welding procedure specification, generate a printout which reports essential information for selecting qualified welders, and provide a method for updating welders based on process usage as permitted by the codes. Codes addressed by the system include American Society of Mechanical Engineers (ASME) Section IX, American Welding Society (AWS) D1.1, AWS D1.3 and AWS D9.1
Date: April 27, 1994
Creator: Davis, J.N.; Etzler, D.J.; Fletcher, D.R.; Jessee, R.M.; Wilson, L.O.; Evans, J.C. et al.
System: The UNT Digital Library
An automated computer misuse detection system for UNICOS (open access)

An automated computer misuse detection system for UNICOS

An effective method for detecting computer misuse is the automatic monitoring and analysis of on-line user activity. This activity is reflected in the system audit record, in the system vulnerability posture, and in other evidence found through active testing of the system. During the last several years we have implemented an automatic misuse detection system at Los Alamos. This is the Network Anomaly Detection and Intrusion Reporter (NADIR). We are currently expanding NADIR to include processing of the Cray UNICOS operating system. This new component is called the UNICOS Realtime NADIR, or UNICORN. UNICORN summarizes user activity and system configuration in statistical profiles. It compares these profiles to expert rules that define security policy and improper or suspicious behavior. It reports suspicious behavior to security auditors and provides tools to aid in follow-up investigations. The first phase of UNICORN development is nearing completion, and will be operational in late 1994.
Date: September 27, 1994
Creator: Jackson, K. A.; Neuman, M. C.; Simmonds, D. D.; Stallings, C. A.; Thompson, J. L. & Christoph, G. G.
System: The UNT Digital Library
Analysis and optimization of an adsorption air conditioner for electric vehicle applications (open access)

Analysis and optimization of an adsorption air conditioner for electric vehicle applications

This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the overall system weight, which includes the cooling system weight and the weight of the battery necessary to provide energy for air conditioner operation. The system with the minimum overall weight is considered to be the best. The results show the optimum values of all the variables, as well as temperatures and amounts adsorbed, for the adsorption and desorption processes. The results indicate that, for the conditions analyzed in this paper, vapor compression air conditioners are superior to adsorption systems, not only because they are lighter, but also because they have a higher COP and are more compact.
Date: July 27, 1994
Creator: Aceves, S. M.
System: The UNT Digital Library
Rotary capacitance transducers for automotive environments (open access)

Rotary capacitance transducers for automotive environments

Rotary transducers for automotive use are briefly discussed. A transducer based on differential capacitance is described that is robust and simple to manufacture. It has the potential to meet cost targets for automotive use. The design is based on a dielectrically coated rotor with a 240-degree conductive segment, turning over a stator with three 120-degree segments. One of these segments is used to supply drive to the isolated rotor segment. The other two segments act as differential capacitors, driven by the rotor. Linearity over about 105 degrees of rotation is within 4%, although special shaping of the plates can reduce this to less than 1%. A full custom CMOS integrated circuit was designed and implemented to interface to the sensor. It mounts on the back of the stator plate. The combination of a single chip and simple mechanical construction leads to a part which may become cost competitive with present resistive sensors.
Date: July 27, 1994
Creator: Bauer, M. L.; Christopher, A. M.; Ericson, M. N.; Kennedy, E. J. & Ramsey, J. A.
System: The UNT Digital Library
Adsorption air conditioner for electric vehicle applications. Revision 1 (open access)

Adsorption air conditioner for electric vehicle applications. Revision 1

This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the overall system weight, which includes the cooling system weight and the weight of the battery necessary to provide energy for air conditioner operation. The system with the minimum overall weight is considered to be the best, because a lower weight results in an increased vehicle range. The results indicate that, for the conditions analyzed in this paper, vapor compression air conditioners are superior to adsorption systems not only because they are lighter, but also because they have a higher COP and are more compact.
Date: July 27, 1994
Creator: Aceves, S.M.
System: The UNT Digital Library
Computer-controlled radiation monitoring system (open access)

Computer-controlled radiation monitoring system

A computer-controlled radiation monitoring system was designed and installed at the Lawrence Livermore National Laboratory`s Multiuser Tandem Laboratory (10 MV tandem accelerator from High Voltage Engineering Corporation). The system continuously monitors the photon and neutron radiation environment associated with the facility and automatically suspends accelerator operation if preset radiation levels are exceeded. The system has proved reliable real-time radiation monitoring over the past five years, and has been a valuable tool for maintaining personnel exposure as low as reasonably achievable.
Date: September 27, 1994
Creator: Homann, S.G.
System: The UNT Digital Library
Field Quality Improvements in Superconducting Magnets for RHIC (open access)

Field Quality Improvements in Superconducting Magnets for RHIC

A number of techniques have been developed and tested to improve the field quality in the superconducting dipole and quadrupole magnets to be used in the Relativistic Heavy Ion Collider (RHIC). These include adjustment in the coil midplane gap to compensate for the allowed and non-allowed harmonics, inclusion of holes and cutouts in the iron yoke to reduce the saturation-induced harmonics, and magnetic tuning shims to correct for the residual errors. We compare the measurements with the calculations to test the validity of these concepts.
Date: June 27, 1994
Creator: Gupta, R.; Jain, A.; Kahn, S.; Morgan, G.; Thompson, P.; Wanderer, P. et al.
System: The UNT Digital Library