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Neutron diffraction study of NiTi during compressive deformation and after shape-memory recovery

Description: Neutron diffraction measurements of internal elastic strains and texture were performed during compressive deformation of martensitic NiTi deforming by twinning. Rietveld refinement of the diffraction spectrum was performed in order to obtain lattice parameter variations and preferred orientation of martensitic variants. The elastic internal strains, are proportional to the externally applied stress but strongly dependent on crystallographic orientation. Plastic deformation by matrix twinning is consistent with type I (1-1-1) twinning, whereby (100) and (011) planes tend to align perpendicular and parallel to the stress axis, respectively. The preferred orientation ratio r according to the model by March and Dollase is proportional to the macroscopic plastic strain for (100) and (011) planes for loading, unloading and shape-memory recovery. To the best of our knowledge, this is the first in situ bulk measurement of reversible twinning in NiTi. Finally, shape-memory recovery results in a marked change of NiTi cell parameters.
Date: September 1995
Creator: Dunand, D. C.; Mari, D.; Bourke, M. A. M. & Goldstone, J. A.
Partner: UNT Libraries Government Documents Department

Medical imaging with coded apertures

Description: Now algorithms were investigated for image reconstruction in emission tomography which could incorporate complex instrumental effects such as might be obtained with a coded aperture system. The investigation focused on possible uses of the wavelet transform to handle non-stationary instrumental effects and analytic continuation of the Radon transform to handle self-absorption. Neither investigation was completed during the funding period and whether such algorithms will be useful remains an open question.
Date: June 16, 1995
Creator: Keto, E. & Libby, S.
Partner: UNT Libraries Government Documents Department

Single Bunch Stability to Monopole Excitation

Description: We study single bunch stability with respect to monopole longitudinal oscillations in electron storage rings. Our analysis is different from the standard approach based on the linearized Vlasov equation. Rather, we reduce the full nonlinear Fokker-Planck equation to a Schroedinger-like equation which is subsequently analyzed by perturbation theory. We show that the Haissinski solution [3] may become unstable with respect to monopole oscillations and derive a stability criterion in terms of the ring impedance. We then discuss this criterion and apply it to a broad band resonator impedance model.
Date: January 19, 1999
Creator: Podobedov, Boris
Partner: UNT Libraries Government Documents Department

Maintenance Action Work Plan for Waste Area Grouping 1 inactive tanks 3001-B, 3004-B, T-30, and 3013 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

Description: This Maintenance Action Work Plan has been prepared to document the activities and procedures for the remediation of four inactive, low-level radioactive tanks at Waste Area Grouping 1, from the Category D list of tanks in the Federal Facility Agreement for the Oak Ridge Reservation (EPA et al. 1994). The four tanks to remediated are tanks 3001-B, 3004-B, T-30, and 3013. Three of the tanks (3001-B, 3004-B, and T-30) will be physically removed from the ground. Because of logistical issues associted with excavation and site access, the fourth tank (3013) will be grouted in place and permanently closed.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

The LCLS X-Ray FEL at SLAC

Description: The design status and R and D plan of a 1.5 Angstrom SASE-FEL at SLAC, called the Linac Coherent Light Source (LCLS), are described. The LCLS utilizes one third of the SLAC linac for the acceleration of electrons to about 15 GeV. The FEL radiation is produced in a long undulator and is directed to an experimental area for its utilization. The LCLS is designed to produce 300 fsec long radiation pulses at the wavelength of 1.5 Angstrom with 9 GW peak power. This radiation has much higher brightness and coherence, as well as shorter pulses, than present 3rd generation sources. It is shown that such leap in performance is now within reach, and is made possible by the advances in the physics and technology of photo-injectors, linear accelerators, insertion devices and free-electron lasers.
Date: February 9, 1999
Creator: Cornacchia, Massimo
Partner: UNT Libraries Government Documents Department

Superlattice Photocathodes for Accelerator-Based Polarized Electron Source Applications

Description: A major improvement in the performance of the SLC was achieved with the introduction of thin strained-layer semiconductor crystals. After some optimization, polarizations of 75-85% became standard with lifetimes that were equal to or better than that of thick unstrained crystals. Other accelerators of polarized electrons, generally operating with a much higher duty factor, have now successfully utilized similar photocathodes. For future colliders, the principal remaining problem is the limit on the total charge that can be extracted in a time scale of 10 to 100 ns. In addition, higher polarization is critical for exploring new physics, especially supersymmetry. However, it appears that strained-layer crystals have reached the limit of their optimization. Today strained superlattice crystals are the most promising candidates for better performance. The individual layers of the superlattice can be designed to be below the critical thickness for strain relaxation, thus in principle improving the polarization. Thin layers also promote high electron conduction to the surface. In addition the potential barriers at the surface for both emission of conduction-band electrons to vacuum and for tunneling of valence-band holes to the surface can be significantly less than for single strained-layer crystals, thus enhancing both the yield at any intensity and also decreasing the limitations on the total charge. The inviting properties of the recently developed AlInGaAs/GaAs strained superlattice with minimal barriers in the conduction band are discussed in detail.
Date: March 22, 1999
Creator: Clendenin, James E
Partner: UNT Libraries Government Documents Department

Results of design calculations. Specification of a prototype zone plate for focusing hard x-rays

Description: A zone plate capable of focusing hard x-rays to less than 1 {mu}m spot size is designed and specified. This design is based on the state-of-art fabrication technology available today. This zone plate consists of Cu/Al layers sputtered alternatively on a round stainless steel core. Parameters of this zone plate are given. The focal length f is given for 8Kev x-rays and the thickness is optimized for focusing efficiency of the same x-ray energy.
Date: January 1991
Creator: Yun, W. B.; Chrzas, J. & Viccaro, P. J.
Partner: UNT Libraries Government Documents Department

Solid Waste Assurance Program Implementation Plan

Description: On June 6, 1995, a waiver to Hanford Site Solid Waste Acceptance Criteria, was approved by the US Department of Energy Richland Operations Office (RL) to replace the low-level, mixed, and transuranic (TRU) generator assessment programs with the Solid Waste Assurance Program (SWAP). This is associated with a waiver that was approved on March 16, 1995 to replace the Storage/Disposal Approval Record (SDAR) requirements with the Waste Specification System (WSS). This implementation plan and the SWAP applies to Solid Waste Disposal (SWD) functions, facilities, and personnel who perform waste acceptance, verification, receipt, and management functions of dangerous, radioactive, and mixed waste from on- and off-site generators who ship to or within the Hanford Site for treatment, storage, and/or disposal (TSD) at SWD TSD facilities.
Date: June 19, 1995
Creator: Irons, L.G.
Partner: UNT Libraries Government Documents Department

Preliminary design and estimate of capital and operating costs for a production scale application of laser decontamination technology

Description: The application of laser ablation technology to the decontamination of radioactive metals, particularly the surfaces of equipment, is discussed. Included is information related to the design, capital and operating costs, and effectiveness of laser ablation technology, based on commercial excimer and Nd:YAG lasers, for the decontamination of production scale equipment.
Date: August 6, 1994
Creator: Pang, Ho-ming & Edelson, M.C.
Partner: UNT Libraries Government Documents Department

Functional design criteria for the self-installing liquid observation well

Description: This document presents the functional design criteria for installing liquid observation wells (LOWs) into single-shell tanks containing ferrocyanide wastes. The LOWs will be designed to accommodate the deployment of gamma, neutron, and electromagnetic induction probes and to interface with the existing tank structure and environment.
Date: June 16, 1995
Creator: Parra, S.A.
Partner: UNT Libraries Government Documents Department

K-Basins S/RIDS

Description: The Standards/Requirements Identification Document (S/RID) is a list of the Environmental, Safety, and Health (ES{ampersand}H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility.
Date: August 1, 1997
Creator: Watson, D.J.
Partner: UNT Libraries Government Documents Department

World nuclear outlook 1995

Description: As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.
Date: September 29, 1995
Partner: UNT Libraries Government Documents Department

Microwave melt and offgas analysis results from a Ferro Corporation{reg_sign} glass frit

Description: In support of the Residue Treatment Technology (RTT) Microwave Solidification project, Waste Projects and Surface Water personnel conducted a series of experiments to determine the feasibility of encapsulating a surrogate sludge waste using the microwave melter. The surrogate waste was prepared by RTT and melted with five varying compositions of low melting glass frit supplied by the Ferro Corporation. Samples were melted using a 50% waste/50% glass frit and a 47.5% waste/47.5% glass frit/5% carbon powder. This was done to evaluate the effectiveness of carbon at reducing a sulfate-based surface scale which has been observed in previous experiments and in full-scale testing. These vitrified samples were subsequently submitted to Environmental Technology for toxicity characteristic leaching procedure (TCLP) testing. Two of the five frits tested in this experiment merit further evaluation as raw materials for the microwave melter. Ferro frit 3110 with and without carbon powder produced a crystalline product which passed TCLP testing. The quality of the melt product could be improved by increasing the melting temperature from 900{degrees}C to approximately 1150-1200{degrees}C. Ferro frit 3249 produced the optimal quality of glass based on visual observations, but failed TCLP testing for silver when melted without carbon powder. This frit requires a slightly higher melting temperature ({ge} 1200{degrees}C) compared to frit 3110 and produces a superior product. In conjunction with this work, Surface Water personnel conducted offgas analyses using a Thermal Desorption Mass Spectrometer (TDMS) on selected formulations. The offgas analyses identified and quantified water vapor (H{sub 2}O), oxygen (O{sub 2}) and carbon oxides (CO and CO{sub 2}), sulfur (S) and sulfur oxides (SO and SO{sub 2}), and nitrogen (N{sub 2}) and nitrogen oxides (NO and NO{sub 2}) that volatilized during glass formation.
Date: March 1, 1995
Creator: Phillips, J.A.; Hoffman, C.R. & Knutson, P.T.
Partner: UNT Libraries Government Documents Department

500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, second quarter 1994, April 1994--June 1994

Description: This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NOx combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NOx reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NOx burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NOx reductions of each technology and evaluate the effects of those reductions on other combustion parameters. Results are described.
Date: September 1, 1995
Partner: UNT Libraries Government Documents Department

HFBR: Review of the technical specifications against the FSAR

Description: The purpose of this review is to determine the adequacy of the High Flux Beam Reactor (HFBR) Technical Specifications for 40 MW operation by comparison with the HFBR Final Safety Analysis Report, particularly the accident analyses chapter. Specifically, the Technical Specifications were compared against the Design Basis Accident (DBA) Analyses presented in the Addendum to the HFBR FSAR for 60 MW Operation. The 60 MW DBA analyses was used since it is more current and complete than the analyses presented in the original FSAR which is considered obsolete. A listing of the required systems and equipment was made for each of the accidents analyzed. Additionally, the Technical Specification instrument setpoints were compared to the DBA analyses parametric values. Also included in this review was a comparison of the Technical Specification Bases against the FSAR and the identification of any differences. The HFBR Operations Procedures Manual (OPM) was also reviewed for any inconsistencies between the FSAR or the Technical Specifications. Upon completion of this review it was determined that the Technical Specifications are well written and the items commented on should not delay the low power restart (40 MW). Additionally, the OPM is also well written and does not require further modification before restart.
Date: January 25, 1990
Creator: Rao, D.V.; Ross, S.B.; Claiborne, E.R.; Darby, J.L. & Clark, R.A.
Partner: UNT Libraries Government Documents Department

Fire modeling of the Heiss Dampf Reaktor containment

Description: This report summarizes Sandia National Laboratories` participation in the fire modeling activities for the German Heiss Dampf Reaktor (HDR) containment building, under the sponsorship of the United States Nuclear Regulatory Commission. The purpose of this report is twofold: (1) to summarize Sandia`s participation in the HDR fire modeling efforts and (2) to summarize the results of the international fire modeling community involved in modeling the HDR fire tests. Additional comments, on the state of fire modeling and trends in the international fire modeling community are also included. It is noted that, although the trend internationally in fire modeling is toward the development of the more complex fire field models, each type of fire model has something to contribute to the understanding of fires in nuclear power plants.
Date: September 1995
Creator: Nicolette, V. F. & Yang, K. T.
Partner: UNT Libraries Government Documents Department

The Carnol process for CO{sub 2} mitigation from power plants and the transportation sector

Description: A CO{sub 2} mitigation process is developed which converts waste CO{sub 2}, primarily recovered from coal-fired power plant stack gases with natural gas, to produce methanol as a liquid fuel and coproduct carbon as a materials commodity. The Carnol process chemistry consists of methane decomposition to produce hydrogen which is catalytically reacted with the recovered waste CO{sub 2} to produce methanol. The carbon is either stored or sold as a materials commodity. A process design is modelled and mass and energy balances are presented as a function of reactor pressure and temperature conditions. The Carnol process is a viable alternative to sequestering CO{sub 2} in the ocean for purposes of reducing CO{sub 2} emissions from coal burning power plants. Over 90% of the CO{sub 2} from the coal burning plant is used in the process which results in a net CO{sub 2} emission reduction of over 90% compared to that obtained for conventional methanol production by steam reforming of methane. Methanol as an alternative liquid fuel for automotive engines and for fuel cells achieves additional CO{sub 2} emission reduction benefits. The economics of the process is greatly enhanced when carbon can be sold as a materials commodity. Improvement in process design and economics should be achieved by developing a molten metal (tin) methane decomposition reactor and a liquid phase, slurry catalyst, methanol synthesis reactor directly using the solvent saturated with CO{sub 2} scrubbed from the power plant stack gases. The benefits of the process warrant its further development.
Date: August 1, 1995
Creator: Steinberg, M.
Partner: UNT Libraries Government Documents Department

Analysis of the effects of corrosion probe on riser 241-AN-102-WST-16 during seismic event

Description: This analysis supports the installation activity of the corrosion probe in Tank 241-AN-102. The probe is scheduled to be installed in Riser 241-AN-102-WST-16 (formerly known as Riser 15B). The purpose of this analysis is to evaluate the potential effect of the corrosion probe on the riser during a credible seismic event. The previous analysis (HNF 1997a) considered only pump jet impingement loading.
Date: November 6, 1998
Creator: ZIADA, H.H.
Partner: UNT Libraries Government Documents Department

Removal of mixing pump in tank 102-AP -- pump drop onto central pit

Description: The mixing pump, if dropped in the pump pit following its removal from the tank, is incapable of compromising the tank structure either locally or in a structural displacement mode to an extent which might allow dispersion of the contents. A drop from 10 ft above the pit floor (considered the maximum credible height) of a pump which is considered perfectly rigid does not approach the required perforation velocity. The velocity required to perforate requires a drop height which is physically impossible to attain with existing cranes. An analysis of the location of the deposition of the strain energy required to match the pump`s impact kinetic energy, the results of which are shown in Table 2, verifies that there is no credible chance for compromise of the tank roof by such a drop.
Date: June 20, 1995
Creator: Jimenez, R. F.
Partner: UNT Libraries Government Documents Department

Controlling incipient oxidation of pyrite for improved rejection. Technical progress report for the ninth quarter, October 1--December 31, 1994

Description: The major objectives of this work are (1) to determine the Eh-pH conditions under which pyrite is stable, (2) to determine the mechanism of the initial stages of pyrite oxidation, and (3) to determine if the semi-conducting properties of pyrite effects its oxidation behavior. It is known that moderate oxidation of pyrite produces a hydrophobic surface product. This hydrophobic product makes it extremely difficult to depress pyrite in coal flotation circuits. The eventual objective of this work is to prevent pyrite oxidation in order to better depress pyrite in coal flotation circuits. It has been shown that by holding the potential of pyrite at its stable potential during fracture, pyrite undergoes neither oxidation nor reduction. It has also been found that fresh pyrite surfaces created by fracture in an electrochemical begin to oxidize at potentials that are about 200 mV more negative than the potentials reported in the literature for pyrite oxidation. This report period, electrochemical impedance spectroscopy (EIS) studies were continued. As discussed in the seventh quarterly progress report, the impedance of pyrite does not show the characteristics expected for either semi-conducting or metallic electrodes. Additional studies were conducted to confirm the anomalous impedance behavior. For this purpose, freshly fractured surfaces were progressively polished on 600 and 1,200 grit silicon carbide paper, and with 0.3 {micro} {alpha}-alumina and 0.05 {micro} {gamma}-alumina micropolish. Polishing is known to introduce defects in the lattice structure of semi-conducting electrodes and it was anticipated that the defects would effect the interfacial capacitance.
Date: July 1, 1995
Creator: Yoon, R.H. & Richardson, P.E.
Partner: UNT Libraries Government Documents Department

Integrated development and testing plan for the plutonium immobilization project

Description: This integrated plan for the DOE Office of Fissile Materials Disposition (MD) describes the technology development and major project activities necessary to support the deployment of the immobilization approach for disposition of surplus weapons-usable plutonium. The plan describes details of the development and testing (D&T) tasks needed to provide technical data for design and operation of a plutonium immobilization plant based on the ceramic can-in-canister technology (''Immobilization Fissile Material Disposition Program Final Immobilization Form Assessment and Recommendation'', UCRL-ID-128705, October 3, 1997). The plan also presents tasks for characterization and performance testing of the immobilization form to support a repository licensing application and to develop the basis for repository acceptance of the plutonium form. Essential elements of the plant project (design, construction, facility activation, etc.) are described, but not developed in detail, to indicate how the D&T results tie into the overall plant project. Given the importance of repository acceptance, specific activities to be conducted by the Office of Civilian Radioactive Waste Management (RW) to incorporate the plutonium form in the repository licensing application are provided in this document, together with a summary of how immobilization D&T activities provide input to the license activity. The ultimate goal of the Immobilization Project is to develop, construct, and operate facilities that will immobilize from about 18 to 50 tonnes (MT) of U.S. surplus weapons usable plutonium materials in a manner that meets the ''spent fuel'' standard (Fissile Materials Storage and Disposition Programmatic Environmental Impact Statement Record of Decision, ''Storage and Disposition Final PEIS'', issued January 14, 1997, 62 Federal Register 3014) and is acceptable for disposal in a geologic repository. In the can-in-canister technology, this is accomplished by encapsulating the plutonium-containing ceramic forms within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2006 and be ...
Date: July 1, 1998
Creator: Kan, T.
Partner: UNT Libraries Government Documents Department

Laser tabbed die: A repairable, high-speed die-interconnection technology. 1994 LDRD final report 93-SR-089

Description: A unique technology for multichip module production is presented. The technology, called Laser Tabbed Die (L-TAB), consists of a method for forming surface-mount-type {open_quotes}gull wing{close_quotes} interconnects on bare dice. The dice are temporarily bonded to a sacrificial substrate which has a polymer thin film coated onto it. The gull wings are formed on the side of the die with a direct-write laser patterning process which allows vertical as well as horizontal image formation. Using the laser patterning system, trenches are formed in a positive electrodeposited photoresist (EDPR) which is plated onto a metal seed layer, allowing copper to be electroplated through the resultant mask. After stripping the resist and the metal seed layer, the polymer film on the substrate is dissolved, releasing the chip with the {open_quotes}gull wings{close_quotes} intact. The chips are then bonded onto a circuit board or permanent substrate with solder or conductive adhesive.
Date: September 1, 1995
Creator: Malba, V. & Bernhardt, A.F.
Partner: UNT Libraries Government Documents Department

Process modeling of hydrothermal treatment of municipal solid waste to form high solids slurries in a pilot scale system

Description: Two models are developed for characterizing the hydrothermal decomposition of municipal solid waste (MSW) in a pilot scale facility. The process modeled involves the use of high pressure steam to directly heat surrogate MSW, newspaper, to temperatures and pressures where decomposition reactions breakdown the organic matter to form a coal like solid having properties which make it suitable as a feedstock for a commercial gasifier. One model uses the ASPEN steady-state simulator. This model is only capable of computing a limited number of process variables. To more adequately deal with the transient behavior of the inherently batch process a second transient model is formulated. The model allows important process temperatures, pressures, gas flows and compositions to be calculated as a function of time. The model has been used to scope possible operating scenarios for proposed pilot scale experiments and these results are presented. Based on computed results a recommendation is made that the first pilot experiment use a dampened feed material containing a water-to-dry newspaper ratio of 0.5 to 1. The transient model predicts that this will result in a slurry product in the reactor vessel after cooldown containing 57 wt.% water.
Date: February 16, 1995
Creator: Thorsness, C.B.
Partner: UNT Libraries Government Documents Department