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Advanced Air Distribution Strategies Improve Performance of Palm Harbor Homes: Building America System Fact Sheet

Description: Palm Harbor Homes (PHH), one of the nations largest producers of manufactured homes, and Building Americas Industrialized Housing Partnership have teamed together to develop air-distribution and duct-sealing strategies that reduce energy use and increase comfort.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department
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ADVANCED HYBRID PARTICULATE COLLECTOR

Description: A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the …
Date: December 1, 2001
Creator: Zhuang, Ye; Miller, Stanley J.; Olderbak, Michelle R. & Gebert, Rich
Partner: UNT Libraries Government Documents Department
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Aspects of Three-Dimensional Imaging by Classical Tomography for Dual Detector Positron Emission Mammography (PEM)

Description: Images from dual detector positron emission mammography (PEM) systems are commonly reconstructed by backprojection methods of classical tomography. Characteristics of three-dimensional (3-D) PEM images were investigated using analytic models, computer simulations, and experimental acquisitions with compact pixellated detectors, in particular depth resolution normal to the detectors. An analytic formula was developed using circular image pixels that models blurring normal to the detectors. The amount of blurring is dependent on the acceptance angle for coincidence events and may vary across the field of view due to geometric limitations on the maximum angle of lines of response normal to the detectors. For experimental acquisitions with line sources and a pixellated lutetium gadolinium oxyorthosilicate (LGSO) detector, depth resolution is broader than predicted by numerical simulations, possibly due to uncorrected randoms or scatter within the scintillator arrays. Iterative image reconstruction with the maximum likelihood expectation maximization (MLEM) algorithm of a compressed breast phantom acquisition with a pixellated gadolinium oxyorthosilicate (GSO) detector shows improved contract compared with backprojection reconstruction. Image reconstruction for dual detector PEM with static detectors represents a case of limited angle tomography with truncated projection data, and there is the opportunity to improve three-dimensional PEM imaging by the use of more sophisticated image reconstruction techniques.
Date: December 1, 2001
Creator: Smith, Mark F.; Majewski, Stan; Weisenberger, Andrew G.; Raylman, Raymond R.; Kieper, Douglas A.; Kalen, Joseph D. et al.
Partner: UNT Libraries Government Documents Department
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Assessing multizone airflow software

Description: Multizone models form the basis of most computer simulations of airflow and pollutant transport in buildings. In order to promote computational efficiency, some multizone simulation programs, such as COMIS and CONTAM, restrict the form that their flow models may take. While these tools allow scientists and engineers to explore a wide range of building airflow problems, increasingly their use has led to new questions not answerable by the current generation of programs. This paper, directed at software developers working on the next generation of building airflow models, identifies structural aspects of COMIS and related programs that prevent them from easily incorporating desirable new airflow models. The paper also suggests criteria for evaluating alternate simulation environments for future modeling efforts.
Date: December 1, 2001
Creator: Lorenzetti, D.M.
Partner: UNT Libraries Government Documents Department
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Biodiesel Blends in Space Heating Equipment.

Description: Biodiesel is a diesel-like fuel that is derived from processing vegetable oils from various sources, such as soy oil, rapeseed or canola oil, and also waste vegetable oils resulting from cooking use. Brookhaven National laboratory initiated an evaluation of the performance of blends of biodiesel and home heating oil in space heating applications under the sponsorship of the Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL). This report is a result of this work performed in the laboratory. A number of blends of varying amounts of a biodiesel in home heating fuel were tested in both a residential heating system and a commercial size boiler. The results demonstrate that blends of biodiesel and heating oil can be used with few or no modifications to the equipment or operating practices in space heating. The results also showed that there were environmental benefits from the biodiesel addition in terms of reductions in smoke and in Nitrogen Oxides (NOx). The latter result was particularly surprising and of course welcome, in view of the previous results in diesel engines where no changes had been seen. Residential size combustion equipment is presently not subject to NOx regulation. If reductions in NOx similar to those observed here hold up in larger size (commercial and industrial) boilers, a significant increase in the use of biodiesel-like fuel blends could become possible.
Date: December 1, 2001
Creator: Krishna, C. R.
Partner: UNT Libraries Government Documents Department
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Building America Developments, September 2000, Information Bulletin Number 1 (Revised)

Description: Building America Developments on-line newsletter highlights the Erie-Ellington Homes publicly-funded housing project in Boston, Massachusetts. A Building America and industry partnership that produced energy-efficient manufactured homes built with foam core panels is featured. Also, Habitat for Humanity dedicates two energy-efficient test houses in East Tennessee, and affordable, healthy homes are offered in metro Atlanta. Upcoming events in the Building America Program are also listed.
Date: December 1, 2001
Creator: Hendron, R.; Anderson, J. & Epstein, K.
Partner: UNT Libraries Government Documents Department
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CATALYTIC GASIFICATION OF COAL USING EUTECTIC SALT MIXTURES

Description: The Gas Research Institute (GRI) estimates that by the year 2010, 40% or more of U.S. gas supply will be provided by supplements including substitute natural gas (SNG) from coal. These supplements must be cost competitive with other energy sources. The first generation technologies for coal gasification e.g. the Lurgi Pressure Gasification Process and the relatively newer technologies e.g. the KBW (Westinghouse) Ash Agglomerating Fluidized-Bed, U-Gas Ash Agglomerating Fluidized-Bed, British Gas Corporation/Lurgi Slagging Gasifier, Texaco Moving-Bed Gasifier, and Dow and Shell Gasification Processes, have several disadvantages. These disadvantages include high severities of gasification conditions, low methane production, high oxygen consumption, inability to handle caking coals, and unattractive economics. Another problem encountered in catalytic coal gasification is deactivation of hydroxide forms of alkali and alkaline earth metal catalysts by oxides of carbon (CO{sub x}). To seek solutions to these problems, a team consisting of Clark Atlanta University (CAU, a Historically Black College and University, HBCU), the University of Tennessee Space Institute (UTSI) and Georgia Institute of Technology (Georgia Tech) proposed to identify suitable low melting eutectic salt mixtures for improved coal gasification. The research objectives of this project were to: Identify appropriate eutectic salt mixture catalysts for coal gasification; Assess agglomeration tendency of catalyzed coal; Evaluate various catalyst impregnation techniques to improve initial catalyst dispersion; Determine catalyst dispersion at high carbon conversion levels; Evaluate effects of major process variables (such as temperature, system pressure, etc.) on coal gasification; Evaluate the recovery, regeneration and recycle of the spent catalysts; and Conduct an analysis and modeling of the gasification process to provide better understanding of the fundamental mechanisms and kinetics of the process.
Date: December 1, 2001
Creator: Yeboah, Dr. Yaw D.; Xu, Dr. Yong; Sheth, Dr. Atul & Agrawal, Dr. Pradeep
Partner: UNT Libraries Government Documents Department
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Closure Report for Corrective Action Unit 407: Roller Coaster RADSAFE Area, Tonopah Test Range, Nevada

Description: This closure report (CR) provides documentation for the closure of the Roller Coaster RADSAFE Area (RCRSA) Corrective Action Unit (CAU) 407 identified in the Federal Facility Agreement and Consent Order (FFACO) (Nevada Division of Environmental Protection [NDEP] et al., 1996). CAU 407 is located at the Tonopah Test Range (TTR), Nevada. The TTR is approximately 225 kilometers (km) (140 miles [mi]) northwest of Las Vegas, Nevada (Figure 1). The RCRSA is located on the northeast comer of the intersection of Main Road and Browne's Lake Road, which is approximately 8 km (5 mi) south of Area 3 (Figure 1). The RCRSA was used during May and June of 1963 to decontaminate vehicles, equipment, and personnel from the Double Tracks and Clean Slate tests. Investigation of the RCRSA was conducted from June through November of 1998. A Corrective Action Decision Document (CADD) (U.S. Department of Energy, Nevada Operations Office [DOEN], 1999) was approved in October of 1999. The purpose of this CR is to: Document the closure activities as proposed in the Corrective Action Plan (CAP) (DOEM, 2000). Obtain a Notice of Completion from the NDEP. Recommend the movement of CAU 407 from Appendix III to Appendix IV of the FFACO. The following is the scope of the closure actions implemented for CAU 407: Removal and disposal of surface soils which were over three times background for the area. Soils identified for removal were disposed of at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS). Excavated areas were backfilled with clean borrow soil located near the site. A soil cover was constructed over the waste disposal pit area, where subsurface constituents of concern remain. The site was fenced and posted as an ''Underground Radioactive Material'' area.
Date: December 1, 2001
Creator: Fitzmaurice, T. M.
Partner: UNT Libraries Government Documents Department
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The Computational Complexity of the Minimum Degree Algorithm

Description: The Minimum Degree algorithm, one of the classical algorithms of sparse matrix computations, is widely used to order graphs to reduce the work and storage needed to solve sparse systems of linear equations. There has been extensive research involving practical implementations of this algorithm over the past two decades. However, little has been done to establish theoretical bounds on the computational complexity of these implementations. We study the Minimum Degree algorithm, and prove time complexity bounds for its widely used variants.
Date: December 1, 2001
Creator: Heggernes, P; Eisenstat, S C; Kumfert, G & Pothen, A
Partner: UNT Libraries Government Documents Department
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Connecting Structure Functions on the Lattice with Phenomenology

Description: We examine the extraction of moments of parton distributions from lattice data, focusing in particular on the chiral extrapolation as a function of the quark mass. Inclusion of the correct chiral behavior of the spin-averaged isovector distribution resolves a long-standing discrepancy between the lattice moments and experiment. We extract the x-dependence of the valence u-d distribution from the lowest few lattice moments, and discuss the implications for the quark mass dependence of meson masses lying on the a{sub 2} Regge trajectory. The role of chiral symmetry in spin-dependent distributions, and in particular the lattice axial vector charge, g{sub A}, is discussed.
Date: December 1, 2001
Creator: Detmold, W.; Melnitchouk, W. & Thomas, A. W.
Partner: UNT Libraries Government Documents Department
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Data Management Guide for FEMIS Version 1.5

Description: The Federal Emergency Management System (FEMIS) is an emergency management planning and response tool. The FEMIS Data Management Guide provides the information needed to manage the data used to support the administrative, user-environment, database management, and operational capabilities of FEMIS.
Date: December 1, 2001
Creator: Bower, John C.; Burnett, Robert A.; Carter, Richard J.; Holter, Nancy A.; Hoza, Mark; Johnson, Daniel M. et al.
Partner: UNT Libraries Government Documents Department
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Decreases in Human Semen Quality with Age Among Healthy Men

Description: The objective of this report is to characterize the associations between age and semen quality among healthy active men after controlling for identified covariates. Ninety-seven healthy, nonsmoking men between 22 and 80 years without known fertility problems who worked for or retired from a large research laboratory. There was a gradual decrease in all semen parameters from 22-80 years of age. After adjusting for covariates, volume decreased 0.03 ml per year (p = 0.001); sperm concentration decreased 2.5% per year (p = 0.005); total count decreased 3.6% per year of age (p < 0.001); motility decreased 0.7% per year (P < 0.001); progressive motility decreased 3.1% per year (p < 0.001); and total progressively motile sperm decreased 4.8% per year (p < 0.001). In a group of healthy active men, semen volume, sperm concentration, total sperm count, and sperm motility decrease continuously between 22-80 years of age, with no evidence of a threshold.
Date: December 1, 2001
Creator: Eskenazi, B.; Wyrobek, A.J.; Kidd, S.A.; Moore, L.; Young, S.S. & Moore, D.
Partner: UNT Libraries Government Documents Department
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Design of High Sensitivity, High Resolution Compact Single Photon Imaging Devices for Small Animal and Dedicated Breast Imaging

Description: Imaging the biodistribution of single photon emitting radiotracers in small animals and in the breast with high resolution and high sensitivity is an important challenge. Recent work has shown that single photon emission computed tomography (SPECT) imaging of small objects with coded aperture collimators and iterative image reconstruction may provide an order of magnitude increase in sensitivity yet maintain high spatial resolution. We propose a new system design with compact detectors for single photon small animal and breast imaging. Key features are (1) mulitpinhole masks for improved sensitivity, (2) pixellated NaI(Tl) scintillator arrays with small crystals for high resolution and (3) flat panel or flangeless compact position sensitive photomultiplier tubes. Analyses for a multipinhole small animal device with four 10 cm x 20 cm detectors and 1.5 mm detector resolution indicate that 0.9-1.3 mm resolution in image space could be achieved for 0.5-0.8 mm diameter pinholes with geometric sensitivity of 0.2-0.6%, where a point in the brain is imaged through 20 pinholes/mask. A design for a multipinhole breast imager incorporates 20 cm x 20 cm pixellated detectors and lower magnification. Predicted image resolution in the center of the field of view is 1.9 mm for 0.8 mm pinholes, with sensitivity of about 0.045% in the center of the field of view for breast tissue imaged through 20 pinholes/mask. Additional modeling, iterative image reconstruction, device component and phantom tests are desirable to optimize device specifications.
Date: December 1, 2001
Creator: Smith, Mark F.; Majewski, Stan; Meikle, Steven R.; Weisenberger, Andrew G.; Popov, Vladmimir & Wojcik, Randolph F.
Partner: UNT Libraries Government Documents Department
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Detection of Methyl Salicylate Transforted by Honeybees (Apis mellifera) Using Solid Phase Microextration (SPME) Fibers

Description: The ultimate goal of many environmental measurements is to determine the risk posed to humans or ecosystems by various contaminants. Conventional environmental monitoring typically requires extensive sampling grids covering several media including air, water, soil and vegetation. A far more efficient, innovative and inexpensive tactic has been found using honeybees as sampling mechanisms. Members from a single bee colony forage over large areas ({approx}2 x 10{sup 6} m{sup 2}), making tens of thousands of trips per day, and return to a fixed location where sampling can be conveniently conducted. The bees are in direct contact with the air, water, soil and vegetation where they encounter and collect any contaminants that are present in gaseous, liquid and particulate form. The monitoring of honeybees when they return to the hive provides a rapid method to assess chemical distributions and impacts (1). The primary goal of this technology is to evaluate the efficiency of the transport mechanism (honeybees) to the hive using preconcentrators to collect samples. Once the extent and nature of the contaminant exposure has been characterized, resources can be distributed and environmental monitoring designs efficiently directed to the most appropriate locations. Methyl salicylate, a chemical agent surrogate was used as the target compound in this study.
Date: December 1, 2001
Creator: BENDER, SUSAN FAE ANN; RODACY, PHILIP J.; BARNETT, JAMES L. & BENDER, GARY L.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF AN IN SITU INSTRUMENT FOR MEASURING MERCURY IN A GAS STREAM

Description: As part of its overall Environmental Management Program, the U.S. Department of Energy (DOE) has developed thermal and incineration processes for treating hazardous mixed wastes. These mixed wastes often contain mercury that is released into the atmosphere during the incineration process. The U.S. Environmental Protection Agency (EPA), as well as many states, clearly views mercury emissions from incinerators and combustion systems as a potential human health problem (1). Although validated batch measurement methods such as EPA Method 29, the Ontario Hydro mercury speciation method, and EPA Method 101A exist for total and speciated mercury, they are difficult and costly to perform. In addition, the data are not available for use until several days later. Continuous emission monitors (CEMs) are a very attractive option because the data are in near real-time, allowing the data to be used as feedback control for mercury control strategies. Also, a properly designed analyzer should require minimal operator input. However, based on the current state of the art, mercury CEMs are not without problems, as demonstrated in recent field tests (2). In addition, they are often bulky and costly to purchase. Sensor Research and Development Corporation (SRD) was contracted by DOE's National Energy Technology Laboratory (formerly the Federal Energy Technology Center [FETC]) to develop a prototype instrument for thermal treatment process continuous emission monitoring applications. The work by SRD for DOE on the mercury CEM was conducted under two different contracts. Work under the first contract began October 1, 1997, and ended June 2000, with a second contract continuing until June 2001. The SRD process has the potential to be the basis for a very low-cost mercury CEM. The initial cost estimates provided by SRD are an order of magnitude lower than any other proposed mercury CEM. Although the instrument will be low-cost, it still has …
Date: December 1, 2001
Creator: Laudal, Dennis L.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF HIGH ACTIVITY, CATALYTIC SYSTEMS FOR NOx REDUCTION

Description: This project was directed at an investigation of catalytic NO{sub x} reduction on carbonaceous supports at low temperatures. The experimental work was conducted primarily in a packed bed reactor/gas flow system that was constructed for this work. The analytical techniques employed were mass spectrometry, NO{sub x} chemiluminescence, and gas chromatography. The experimental plan was focused on steady-state reactivity experiments, followed by temperature programmed desorption (TPD) of surface intermediates, and also selected temperature-programmed reaction (TPR) experiments. Both uncatalyzed and catalyzed (potassium-promoted) phenolic resin char, were investigated as well as the catalytic effect of additional CO in the gas phase.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department
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EARLY ENTRANCE CO-PRODUCTION PLANT - DECENTRALIZED GASIFICATION COGENERATION TRANSPORTATION FUELS AND STEAM FROM AVAILABLE FEEDSTOCKS

Description: Waste Processors Management, Inc. (WMPI), along with its subcontractors Texaco Power & Gasification, SASOL Technology Ltd., and Nexant Inc. entered into a Cooperative Agreement DE-FC26-00NT40693 with the US Department of Energy (DOE), National Energy Technology Laboratory (NETL) to assess the techno-economic viability of building an Early Entrance Co-Production Plant (EECP) in the US to produce ultra clean Fischer-Tropsch (FT) transportation fuels with either power or steam as the major co-product. The EECP designs emphasize on recovery and gasification of low-cost coal waste (culm) from coal clean operations and will assess blends of the culm and coal or petroleum coke as feedstocks. The project is being carried out in three phases. Phase I involves definition of concept and engineering feasibility study to identify areas of technical, environmental and financial risk. Phase II consists of an experimental testing program designed to validate the coal waste mixture gasification performance. Phase III involves updating the original EECP design, based on results from Phase II, to prepare a preliminary engineering design package and financial plan for obtaining private funding to build a 5,000 BPD coal gasification/liquefaction plant next to an existing co-generation plant in Gilberton, Schuylkill County, Pennsylvania.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department
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Ecological Monitoring and Compliance Program Fiscal Year 2001

Description: The Ecological Monitoring and Compliance program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office, monitors the ecosystem of the Nevada Test Site (NTS) and ensures compliance with laws and regulations pertaining to NTS biota. This report summarizes the program's activities conducted by Bechtel Nevada during fiscal year 2001. Program activities included: (1) biological surveys at proposed construction sites, (2) desert tortoise compliance, (3) ecosystem mapping and data management, (4) sensitive species and unique habitat monitoring, and (5) biological monitoring at the HAZMAT Spill Center. Biological surveys for the presence of sensitive species were conducted for 23 NTS projects. Eleven sites were in desert tortoise habitat. These projects have the potential to disturb a total of 588 acres, where 568 acres of disturbance would be off-road driving. No tortoises were found in or displaced from project areas, and no tortoise s were accidentally injured or killed at project areas. One tortoise was crushed by a vehicle on a paved road. A topical report describing the classification of habitat types on the NTS was completed and distributed. The report is the culmination of three years of field vegetation mapping and the analysis of vegetation data from over 1,500 ecological landform units. Compilation of historical wildlife data was initiated. A long-term monitoring plan for important plant species that occur on the NTS was completed. Site-wide monitoring was conducted for the western burrowing owl, bat species of concern, wild horses, and raptor nests. Sixty-nine of 77 known owl burrows were monitored. As in previous years, some owls were present year round on the NTS. An overall decrease in active owl burrows was observed within all three ecoregions (Mojave Desert, Transition, Great Basin Desert) from October through January. An increase in active owl burrows was observed from mid March …
Date: December 1, 2001
Creator: Wills, C. A.
Partner: UNT Libraries Government Documents Department
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