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Nondestructive Evaluation of Ceramic Candle Filters Using Vibration Response

Description: This study aims at the development of an effective nondestructive evaluation technique to predict the remaining useful life of a ceramic candle filter during a power plant's annual maintenance shutdown. The objective of the present on-going study is to establish the vibration signatures of ceramic candle filters at varying degradation levels due to different operating hours, and to study the various factors involving the establishment of the signatures.
Date: July 1, 1997
Creator: Chen, Roger H. L.; Kiriakidis, Alejandro C. & Peng, Steve W.
Partner: UNT Libraries Government Documents Department

Size effect and detonation front curvature

Description: Heat flow in a cylinder with internal heating is used as a basis for deriving a simple theory of detonation front curvature, leading to the prediction of quadratic curve shapes. A thermal conductivity of 50 MW/mm{sup 2} is found for TATB samples.
Date: July 1, 1997
Creator: Souers, P. C., LLNL
Partner: UNT Libraries Government Documents Department

Enhanced Control of Mercury and other HAP by Innovative Modifications to Wet FGD Processes

Description: The overall objective of this project was to learn more about controlling emissions of hazardous air pollutants (HAPs) from coal-fired power plants that are equipped with wet flue gas desulfurization (FGD) systems. The project was included by FETC as a Phase I project in its Mega-PRDA program. Phase I of this project focused on three research areas. These areas in order of priority were: (1) Catalytic oxidation of vapor-phase elemental mercury; (2) Enhanced particulate-phase HAPs removal by electrostatic charging of liquid droplets; and (3) Enhanced mercury removal by addition of additives to FGD process liquor. Mercury can exist in two forms in utility flue gas--as elemental mercury and as oxidized mercury (predominant form believed to be HgCl{sub 2}). Previous test results have shown that wet scrubbers effectively remove the oxidized mercury from the gas but are ineffective in removing elemental mercury. Recent improvements in mercury speciation techniques confirm this finding. Catalytic oxidation of vapor-phase elemental mercury is of interest in cases where a wet scrubber exists or is planned for SO{sub 2} control. If a low-cost process could be developed to oxidize all of the elemental mercury in the flue gas, then the maximum achievable mercury removal across the existing or planned wet scrubber would increase. Other approaches for improving control of HAPs included a method for improving particulate removal across the FGD process and the use of additives to increase mercury solubility. This paper discusses results related only to catalytic oxidation of elemental mercury.
Date: July 1, 1997
Creator: Hargrove, O. W.; Carey, T. R.; Richardson, C. F.; Skarupa, R. C.; Meserole, F. B.; Rhudy, R. G. et al.
Partner: UNT Libraries Government Documents Department

Mercury speciation measurements on a 10 MW{sub e} coal-fired boiler simulator

Description: The current trends towards deregulation of electric utilities, air toxic regulations and stringent fine particulate emissions reflect an increased need for coal-based research. In response, Babcock and Wilcox invested in the state-of-the-art 100 million Btu/hr (10 MW, equivalent) Clean Environment Development Facility (CEDF) located in Alliance, Ohio. The representative combustion conditions, flow patterns and residence times permit direct scale-up of CEDF test results to commercial boilers and pollution control devices. In cooperation with the U.S. Department of Energy and the Ohio Coal Development Office within the Ohio Office of Development, B&W is employing the CEDF to conduct a five-year project aimed at the development of practical, cost-effective strategies for reducing the emissions of hazardous air pollutants from coal-fired boilers. The project specifically targets the control of mercury, the trace element under close scrutiny by the EPA. Due to the various forms of mercury emissions from coal-fired boilers, accurate mercury speciation measurements are required to develop mercury control strategies. Current uncertainty in the accuracy and mercury speciation capability of mercury sampling methods led B&W to use both EPA Method 29 and the Ontario Hydro procedures to measure mercury emissions from CEDF pollution control devices. A comparison of the speciated mercury emissions is presented.
Date: June 1, 1997
Creator: Evans, A.P. & Nevitt, K.D.
Partner: UNT Libraries Government Documents Department

Orbit dynamics for unstable linear motion

Description: A treatment is given of the orbit dynamics for linear unstable motion that allows for the zeros in the beta function and makes no assumptions about the realness of the betatron and phase functions. The phase shift per turn is shown to be related to the beta function and the number of zeros the beta function goes through per turn. The solutions of the equations of motion are found in terms of the beta function.
Date: July 1997
Creator: Parzen, G.
Partner: UNT Libraries Government Documents Department

Ceramic vane demonstration in an industrial turbine

Description: A DOE program with Allison Engine Co. will demonstrate ceramic vanes in an industrial turbine. First-stage ceramic vanes and metallic mounts are to be designed, fabricated, and operated in a short-term engine test (up to 50 hr). The vanes and mounts will then be retrofitted into an existing turbine for operation at a commercial site for up to 8000 hr. They have been designed. Thermal and stress analyses of the vanes have calculated acceptable fast fracture stress levels and probabilities of survival > 99.99% for turbine continuous power and emergency shutdown (thermal shock) conditions. Max calculated steady-state stress is 169 MPa at 1182 C, so currently available ceramics appear to provide acceptable fast fracture strengths for use in industrial turbines. Long-term materials test will evaluate the lifetimes and retained strength of ceramics at stress and temperature levels in the range calculated from the ceramic vane analyses. Results of these tests will support on which vane material will be used in the long duration turbine demonstration. A successful demonstration could provide a basis for incorporating first-stage ceramic vanes into current generation industrial turbines and also the introduction of ceramic airfoils into downstream rows of future high temperature Advanced Turbine System (ATS) engines.
Date: April 1, 1997
Creator: Wenglarz, R.A.; Calcuttawala, S.M. & Pope, J.E.
Partner: UNT Libraries Government Documents Department

Characterization of interphase structure using neutron reflection

Description: Neutron reflection is one of only a few characterization techniques which can be used to study buried interfaces in situ. While restricted to model samples, interfacial density and composition profiles can be obtained with a resolution of {approx}5 {angstrom} using isotopic substitution (typically H/D for organic materials). We are using neutron reflection to address several problems of fundamental importance to the durability of organic/inorganic interphases. One important focus of this study is water adsorption within interphases with and without coupling agents. From the time and temperature dependence of moisture uptake and removal in vacuum, information regarding the nature of the interaction of water with the interphase species can be obtained.
Date: May 1, 1997
Creator: Kent, M.S.; McNamara, W.F. & Domeier, L.
Partner: UNT Libraries Government Documents Department

Bose condensation in {sup 4}He and neutron scattering

Description: The discovery of superfluidity in liquid {sup 4}He below T{sub {lambda}} = 2.17 K, and its phenomenological characterization since then, has been one of the great success stories of condensed matter physics. The relation of superfluidity to the behavior of atoms was conjectured by F. London in 1938. Superfluidity is a manifestation of the Bose condensation of helium atoms, the extensive occupation of the zero momentum state. Ever since {sup 4}He has been the paradigm in the search for Bose condensates in other systems. At the Pune meeting scientists have heard exciting new evidence for Bose condensates of laser cooled alkali atoms in magnetic traps, of excitons in Cu{sub 2}O, and possibly pre-formed Cooper pairs of electrons in the high {Tc} perovskite superconductors. There remains the holy-grail of forming a Bose condensate in spin-polarized hydrogen. In the current excitement for new types of Bose condensates, and new phenomena such as atom lasers, it may be useful to recall the older story of the experimental verification of a relation between superfluidity and Bose condensation in {sup 4}He. This topic has been investigated over many years by neutron scattering experiments and quantum many-body theory. The authors goal is to illustrate the difficulties of establishing the existence of a Bose condensate in a strongly interacting system, even though its macroscopic effects are manifest. The author assumes readers have access to a review by Silver and Sokol which emphasizes the neutron scattering theory through 1990 and a review by Snow and Sokol of the deep inelastic neutron scattering (DINS) experiments through 1995.
Date: April 1, 1997
Creator: Silver, R.N.
Partner: UNT Libraries Government Documents Department

Rare kaon decays

Description: The phenomenology of rare kaon decays is reviewed, with emphasis on tests of standard model flavordynamics.
Date: January 1, 1997
Creator: Buchalla, G.
Partner: UNT Libraries Government Documents Department

Overcoming weak intrinsic depolarizing resonances with energy-jump

Description: In the recent polarized proton runs in the AGS, a 5% partial snake was used successfully to overcome the imperfection depolarizing resonances. Polarized proton beam was accelerated up to the required RHIC injection energy of 25 GeV. However, significant amount of polarization was lost at 0+{nu}{sub y}, 12+{nu}{sub y} and 36+{nu}{sub y}, which is believed to be partially due to the coupling resonances. To overcome the coupling resonance, an energy-jump was generated by rapidly changing the beam circumference using the powerful AGS rf system. It clearly demonstrates that the novel energy-jump method can successfully overcome coupling resonances and weak intrinsic resonances.
Date: July 1, 1997
Creator: Huang, H.; Ahrens, L. & Alessi, J.G.
Partner: UNT Libraries Government Documents Department

Measurement of storage ring motion at the advanced light source

Description: The mechanical stability of the Advanced Light Source storage ring is examined over a period of 1.5 years from the point of view of floor motion. The storage ring beam position monitor stability is examined under various operating conditions.
Date: May 1997
Creator: Krebs, G.F.
Partner: UNT Libraries Government Documents Department

Production-scale LLW and RMW solidification system operational testing at Argonne National Laboratory-East (ANL-E)

Description: Argonne National Laboratory-East (ANL-E) has begun production-scale testing of a low-level waste and radioactive mixed waste solidification system. This system will be used to treat low-level and mixed radioactive waste to meet land burial requirements. The system can use any of several types of solidification media, including a chemically bonded phosphate ceramic developed by ANL-E scientists. The final waste product will consist of a solidified mass in a standard 208-liter drum. The system uses commercial equipment and incorporates several unique process control features to ensure proper treatment. This paper will discuss the waste types requiring treatment, the system configuration, and operation results for these waste streams.
Date: April 1, 1997
Creator: Wescott, J.; Wagh, A.; Singh, D.; Nelson, R. & No, H.
Partner: UNT Libraries Government Documents Department

Importance of emergency response actions to reactor accidents within a probabilistic consequence assessment model

Description: An uncertainty and sensitivity analysis of early health consequences of severe accidents at nuclear power plants as a function of the emergency response parameters has been performed using a probabilistic consequence assessment code. The importance of various emergency response parameters in predicting the consequences for a range of accident source terms was determined through training a neural network algorithm which relates the sensitivity of the output to various choices of the input. Extensions of this approach should be helpful to planners in prioritizing the emergency responses at nuclear power plants.
Date: March 1, 1997
Creator: Mubayi, V. & Neymotin, L.
Partner: UNT Libraries Government Documents Department

Prediction of tilted capillary barrier performance

Description: Capillary barriers, consisting of tilted fine-over-coarse layers under unsaturated conditions, have been suggested as landfill covers to divert water infiltration away from sensitive underground regions, especially for arid and semi-arid regions. The Hydrological Evaluation of Landfill Performance (HELP) computer code is an evaluation tool for landfill covers used by designers and regulators. HELP is a quasi-two-dimensional model that predicts moisture movement into and through the underground soil and waste layers. Processes modeled within HELP include precipitation, runoff, evapotranspiration, unsaturated vertical drainage, saturated lateral drainage, and leakage through liners. Unfortunately, multidimensional unsaturated flow phenomena that are necessary for evaluating tilted capillary barriers are not included in HELP. Differences between the predictions of the HELP and those from a multidimensional unsaturated flow code are presented to assess the two different approaches. Comparisons are presented for the landfill covers including capillary barrier configurations at the Alternative Landfill Cover Demonstration (ALCD) being conducted at Sandia.
Date: April 1, 1997
Creator: Webb, S.W.; McCord, J.T. & Dwyer, S.F.
Partner: UNT Libraries Government Documents Department

Designing a fiber-optic beam delivery system

Description: One of the advantages offered by visible and NIR lasers over CO and CO{sub 2} lasers is that they can be delivered through optical fibers. Fiber-optic beam delivery is ideal when the beam must be delivered along a complex path or processing requires complicated manipulation of the beam delivery optics. Harnessing the power of a high-power laser requires that knowledgeable and prudent choices be made when selecting the laser and its beam delivery system. The purpose of this paper is to discuss a variety of issues important when designing a beam delivery system-data obtained with high power Nd:YAG lasers will be used as illustrative examples. (1) Multimode optical fibers are used for high-power applications. The fiber imposes, to varying degrees, a structure on the beam that is different from the laser output. Fibers degrade the beam quality, although the degree of degradation is dependent on the fiber length, diameter and type. Smaller fibers tend to produce less degradation to beam quality, but the minimum usable fiber size is limited by the quality of the laser beam, focusing optic and the numerical aperture of the fiber. (2) The performance of the beam delivery system is ultimately determined by the quality of the optics. Therefore, well-corrected optics are required to realize the best possible performance. Tests with both homogeneous and GRADIUM{trademark} lenses provide insights into evaluating the benefits offered by improvements in the output optics from gradient-index, aspheric and multi-element lens systems. Additionally, these tests illustrate the origins of variable focused spot size and position with increasing laser power. (3) The physical hardware used in the beam delivery system will have several characteristics which enhance its functionality and ease of use, in addition to facilitating the use of advanced diagnostics and monitoring techniques.
Date: March 1, 1997
Creator: Hunter, B.V.; Leong, K.H. & Sanders, P.G.
Partner: UNT Libraries Government Documents Department

Phase equilibria in the system H{sub 2}O-NaCl-KCl-MgCl{sub 2} relevant to salt cake processing

Description: One waste product in recycling of Al is salt cake, a mixture of Al, salts, and residue oxides. Several methods have been proposed to recycle salt cake, one involving high-temperature leaching of salts from the salt cake. The salt composition can be approximated as a mixture predominantly of NaCl and KCl salts, with lesser amounts of Mg chloride. In order to better assess the feasibility of recycling salt cake, an experimental study was conducted of phase equilibria in the system H{sub 2}O-NaCl-KCl-MgCl{sub 2} at pressure (P), temperature (T), and composition conditions appropriate for high- temperature salt cake recycling. These experiments were designed to evaluate the effect of small amounts (2-10 wt%) of MgCl{sub 2} on solubilities of halite (NaCl) and sylvite (KCl) in saturated solutions (30-50 wt% NaCl+KCl; NaCl:KCl = 1:1 and 3:1) at elevated P and T.
Date: February 1, 1997
Creator: Bodnar, R.J.; Vityk, M.O.; Hryn, J.N. & Mavrogenes, J.
Partner: UNT Libraries Government Documents Department

Optimal measurement of surface shortwave irradiance using current instrumentation -- the ARM experience

Description: Shortwave (solar) measurements of surface irradiance for clear sky conditions disagree with a number of different models. Betts used the European Center for Medium-range Forecasts (ECMWF) shortwave model to calculate surface irradiance that were 5-10 percent higher than measurements. Wild used a different formulation of the ECMWF shortwave model, but found that the model overpredicted clear-sky shortwave and average of 3 percent. Ding and Wang used data from the Atmospheric Radiation Measurement (ARM) program and found that the GENESIS GCM shortwave model, likewise, overpredicted clear-sky irradiance by about 4 percent. To help resolve the measurement dilemma, reference instruments were deployed in April 1996 at the Southern Great Plains ARM site central facility very near the shortwave measurements. The rest of the paper describes the experiment undertaken to ascertain total horizontal shortwave irradiance at the surface, including a separation of the direct normal and diffuse horizontal components. Results and a discussion of same concludes the paper.
Date: March 1, 1997
Creator: Michalsky, J.; Rubes, M.; Stoffel, T.; Wesley, M.; Splitt, M. & DeLuisi, J.
Partner: UNT Libraries Government Documents Department

The interplay of fractures and sedimentary architecture: Natural gas from reservoirs in the Molina sandstones, Piceance Basin, Colorado

Description: The Molina Member of the Wasatch Formation produces natural gas from several fields along the Colorado River in the Piceance Basin, northwestern Colorado. The Molina Member is a distinctive sandstone that was deposited in a unique fluvial environment of shallow-water floods. This is recorded by the dominance of plane-parallel bedding in many of the sandstones. The Molina sandstones crop out on the western edge of the basin, and have been projected into the subsurface and across the basin to correlate with thinner sandy units of the Wasatch Formation at the eastern side of the basin. Detailed study, however, has shown that the sedimentary characteristics of the type-section Molina sandstones are incompatible with a model in which the eastern sandstones are its distal facies equivalent. Rather, the eastern sandstones represent separate and unrelated sedimentary systems that prograded into the basin from nearby source-area highlands. Therefore, only the subsurface {open_quotes}Molina{close_quotes} reservoirs that are in close proximity to the western edge of the basin are continuous with the type-section sandstones. Reservoirs in the Grand Valley and Rulison gas fields were deposited in separate fluvial systems. These sandstones contain more typical fluvial sedimentary structures such as crossbeds and lateral accretion surfaces. Natural fractures play an important role in enhancing the conductivity and permeability of the Molina and related sandstones of the Wasatch Formation.
Date: March 1, 1997
Creator: Lorenz, J.C.
Partner: UNT Libraries Government Documents Department

Modeling and design of a reload PWR core for a 48-month fuel cycle

Description: The objective of this research was to use state-of-the-art nuclear and fuel performance packages to evaluate the feasibility and costs of a 48 calendar month core in existing pressurized water reactor (PWR) designs, considering the full range of practical design and economic considerations. The driving force behind this research is the desire to make nuclear power more economically competitive with fossil fuel options by expanding the scope for achievement of higher capacity factors. Using CASMO/SIMULATE, a core design with fuel enriched to 7{sup w}/{sub o} U{sup 235} for a single batch loaded, 48-month fuel cycle has been developed. This core achieves an ultra-long cycle length without exceeding current fuel burnup limits. The design uses two different types of burnable poisons. Gadolinium in the form of gadolinium oxide (Gd{sub 2}O{sub 3}) mixed with the UO{sub 2} of selected pins is sued to hold down initial reactivity and to control flux peaking throughout the life of the core. A zirconium di-boride (ZrB{sub 2}) integral fuel burnable absorber (IFBA) coating on the Gd{sub 2}O{sub 3}-UO{sub 2} fuel pellets is added to reduce the critical soluble boron concentration in the reactor coolant to within acceptable limits. Fuel performance issues of concern to this design are also outlined and areas which will require further research are highlighted.
Date: May 1997
Creator: McMahon, M. V.; Driscoll, M. J. & Todreas, N. E.
Partner: UNT Libraries Government Documents Department

Development of a database management system for Coal Combustion By-Products (CCBs)

Description: Coal combustion by-products (CCBs) are produced in high volumes worldwide. Utilization of these materials is economically and environmentally advantageous and is expected to increase as disposal costs increase. The American Coal Ash Association (ACAA) is developing a database to contain characterization and utilization information on CCBs. This database will provide information for use by managers, marketers, operations personnel, and researchers that will aid in their decision making and long-term planning for issues related to CCBs. The comprehensive nature of the database and the interactive user application will enable ACAA members to efficiently and economically access a wealth of data on CCBs and will promote the technically sound, environmentally safe, and commercially competitive use of CCBs.
Date: June 1, 1997
Creator: O`Leary, E.M.; Peck, W.D. & Pflughoeft-Hassett, D.F.
Partner: UNT Libraries Government Documents Department

A standard FODO lattice with adjustable momentum compaction

Description: An existing lattice made of identical FODO cells can be modified to have adjustable momentum compaction. The modified lattice consists of repeating superperiods of four FODO cells where every two cells have different horizontal phase advance. In existing FODO cell rings an additional quad bus is required for every two consecutive cells. This allows tuning of the momentum compaction or {gamma}{sub t} could be an imaginary number. A drawback of this modification is relatively large values of the dispersion function (two or three times larger than in the regular FODO cell design).
Date: July 1, 1997
Creator: Trbojevic, D. & Courant, E.
Partner: UNT Libraries Government Documents Department

Analytical prediction of the location of ductility dip cracking in the trans-varestraint test

Description: Some NiCrFe weld metals exhibit decreased ductility over a temperature range known as the {open_quotes}ductility dip{close_quotes} temperature (DDT) range. Ductility dip cracking (DDT) is a phenomenon which occurs in a zone bounded by the DDT range on its sides and a threshold plastic strain on its bottom as shown in figure 1. Figure 1 illustrates how ductility varies as weld metal cools from the solidus temperature for materials with and without a ductility dip. The purpose of this work is to demonstrate the ability to predict the location of the DDC in a Trans-Varestraint Test (TVT) for a specimen machined from a weld deposited EN52 plate. The DDC predictions require a combination of Trans-Varestraint testing and finite element analysis. The test provides the threshold value of externally applied nominal strain below which DDC does not occur. The analysis provides the corresponding threshold local or peak strain. The threshold local plastic strain level and the DDT range are used to predict the location of the DDC. The ultimate purpose of this work is to evaluate susceptibility of highly constrained, component welds to DDC. Test results for Trans-Varestraint Testing for a weld deposited EN52 plate are reported in reference. The ability to predict the location of the DDC in the Trans-Varestraint Test using the techniques reported herein is demonstrated by showing good comparison between the analytical results and the test data.
Date: May 1, 1997
Creator: Singh, I.; Kroenke, W. & Cola, M.
Partner: UNT Libraries Government Documents Department