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Use of the GranuFlow Process in Coal Preparation Plants to Improve Energy Recovery and Reduce Coal Processing Wastes (open access)

Use of the GranuFlow Process in Coal Preparation Plants to Improve Energy Recovery and Reduce Coal Processing Wastes

With the increasing use of screen-bowl centrifuges in today's fine coal cleaning circuits, a significant amount of low-ash, high-Btu coal can be lost during the dewatering step due to the difficulty in capturing coal of this size consist (< 100 mesh or 0.15mm). The GranuFlow{trademark} technology, developed and patented by an in-house research group at DOE-NETL, involves the addition of an emulsified mixture of high-molecular-weight hydrocarbons to a slurry of finesized coal before cleaning and/or mechanical dewatering. The binder selectively agglomerates the coal, but not the clays or other mineral matter. In practice, the binder is applied so as to contact the finest possible size fraction first (for example, froth flotation product) as agglomeration of this fraction produces the best result for a given concentration of binder. Increasing the size consist of the fine-sized coal stream reduces the loss of coal solids to the waste effluent streams from the screen bowl centrifuge circuit. In addition, the agglomerated coal dewaters better and is less dusty. The binder can also serve as a flotation conditioner and may provide freeze protection. The overall objective of the project is to generate all necessary information and data required to commercialize the GranuFlow{trademark} Technology. The technology …
Date: December 31, 2005
Creator: Shirey, Glenn A. & Akers, David J.
Object Type: Report
System: The UNT Digital Library
Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations (open access)

Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations

This report summarizes the research efforts on the DOE supported research project Percussion Drilling (DE-FC26-03NT41999), which is to significantly advance the fundamental understandings of the physical mechanisms involved in combined percussion and rotary drilling, and thereby facilitate more efficient and lower cost drilling and exploration of hard-rock reservoirs. The project has been divided into multiple tasks: literature reviews, analytical and numerical modeling, full scale laboratory testing and model validation, and final report delivery. Literature reviews document the history, pros and cons, and rock failure physics of percussion drilling in oil and gas industries. Based on the current understandings, a conceptual drilling model is proposed for modeling efforts. Both analytical and numerical approaches are deployed to investigate drilling processes such as drillbit penetration with compression, rotation and percussion, rock response with stress propagation, damage accumulation and failure, and debris transportation inside the annulus after disintegrated from rock. For rock mechanics modeling, a dynamic numerical tool has been developed to describe rock damage and failure, including rock crushing by compressive bit load, rock fracturing by both shearing and tensile forces, and rock weakening by repetitive compression-tension loading. Besides multiple failure criteria, the tool also includes a damping algorithm to dissipate oscillation energy …
Date: December 31, 2005
Creator: Bruno, Michael S.
Object Type: Report
System: The UNT Digital Library
An Investigation to Resolve the Interaction Between Fuel Cell, Power Conditioning System and Application Loads (open access)

An Investigation to Resolve the Interaction Between Fuel Cell, Power Conditioning System and Application Loads

Development of high-performance and durable solidoxide fuel cells (SOFCs) and a SOFC power-generating system requires knowledge of the feedback effects from the power-conditioning electronics and from application-electrical-power circuits that may pass through or excite the power-electronics subsystem (PES). Therefore, it is important to develop analytical models and methodologies, which can be used to investigate and mitigate the effects of the electrical feedbacks from the PES and the application loads (ALs) on the reliability and performance of SOFC systems for stationary and non-stationary applications. However, any such attempt to resolve the electrical impacts of the PES on the SOFC would be incomplete unless one utilizes a comprehensive analysis, which takes into account the interactions of SOFC, PES, balance-of-plant system (BOPS), and ALs as a whole. SOFCs respond quickly to changes in load and exhibit high part- and full-load efficiencies due to its rapid electrochemistry, which is not true for the thermal and mechanical time constants of the BOPS, where load-following time constants are, typically, several orders of magnitude higher. This dichotomy can affect the lifetime and durability of the SOFCSs and limit the applicability of SOFC systems for load-varying stationary and transportation applications. Furthermore, without validated analytical models and investigative design …
Date: December 31, 2005
Creator: Mazumder, Sudip K.
Object Type: Report
System: The UNT Digital Library
A Strong Hot Spot Theorem (open access)

A Strong Hot Spot Theorem

A real number alpha is said to be b-normal if every m-long string of digits appears in the base-b expansion of alpha with limiting frequency b-m. We prove that alpha is b-normal if and only if it possesses no base-b ''hot spot''. In other words, alpha is b-normal if and only if there is no real number y such that smaller and smaller neighborhoods of y are visited by the successive shifts of the base-b expansion of alpha with larger and larger frequencies, relative to the lengths of these neighborhoods
Date: December 31, 2005
Creator: Bailey, David H. & Misiurewicz, Michal
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1 - December 31, 2005 (open access)

Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1 - December 31, 2005

Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,097.6 hours (0.95 × 2,208 hours this quarter). The OPSMAX for the North Slope of Alaska (NSA) locale is 1,987.2 hours (0.90 × …
Date: December 31, 2005
Creator: Sisterson, D. L.
Object Type: Report
System: The UNT Digital Library
Big Sky Carbon Sequestration Partnership (open access)

Big Sky Carbon Sequestration Partnership

The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I are organized into four areas: (1) Evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; (2) Development of GIS-based reporting framework that links with national networks; (3) Design of an integrated suite of monitoring, measuring, and verification technologies, market-based opportunities for carbon management, and an economic/risk assessment framework; (referred to below as the Advanced Concepts component of the Phase I efforts) and (4) Initiation of a comprehensive education and outreach program. As a result of the Phase I activities, the groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that complements the ongoing DOE research agenda in Carbon Sequestration. The geology of the Big Sky Carbon Sequestration Partnership Region is favorable for the potential sequestration of enormous volume of CO{sub 2}. The United States Geological Survey (USGS 1995) identified …
Date: December 31, 2005
Creator: Capalbo, Susan
Object Type: Report
System: The UNT Digital Library
Rhodium-105 Bombesin Analogs for Prostate Cancer Radiotherapy (open access)

Rhodium-105 Bombesin Analogs for Prostate Cancer Radiotherapy

Over the period of this grant (11/01/2001 to 12/31/2005), the consistent and reproducible production of Rh-105, synthesis and evaluation of three new chelate systems based on hydroxymethyl phosphines, development of a new non-hydroxymethyl phosphine N{sub 2}P{sub 2} chelate system, conjugation of two of the chelates to the bombesin peptide analog BBN[7-14]NH{sub 2}, evaluation of the bombesin conjugates and their Rh-105 complexes for stability, cell binding affinity, and in vivo biodistribution in normal mice has been developed. The BBN analogs bind to GRP receptors that are overexpressed on PC-3 prostate tumor cells. A dedicated glove box is used for the separation and isolation of {sup 105}Rh from the target ({sup 104}Ru). All tubing/connections/valves from the point of the Cl{sub 2} tank are made of Teflon to minimize/eliminate the introduction of any metal into the process (e.g., iron from stainless steel corrosion). The separation of {sup 105}Rh produced from the enriched {sup 104}Ru target involves oxidation of the enriched {sup 104}Ru metal target to ruthenium tetroxide with chlorine gas and sodium hydroxide solution to generate hypochlorite in situ. The RuO4 is removed by distillation and the {sup 105}Rh remaining in the reaction vial is converted into {sup 105}Rh-chloride by acidification with hydrochloric …
Date: December 31, 2005
Creator: Silvia S. Jurisson, PhD
Object Type: Report
System: The UNT Digital Library
Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles (open access)

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows: (1) EMISSIONS--NO{sub x} = 0.50 g/mi; PM = 0.05 g/mi; CO = 2.8 g/mi; and NMHC = 0.07 g/mi. California decided to issue new and even tougher LEV II light truck regulations late in 1999. EPA also issued its lower Tier 2 regulations late in 2000. The net result was that the targets for this diesel engine project were lowered, and these goals were eventually modified by the publication of Federal Tier 2 emission standards early in 2000 to the following: NO{sub x} = 0.07 g/mi; and PM = 0.01 g/mi. (2) FUEL ECONOMY--The fuel economy goal was 50 percent MPG improvement (combined city/highway) over the 1997 gasoline powered light truck or sport utility vehicle in the vehicle class for which this diesel engine is being designed to replace. The goal for fuel economy remained at 50 percent MPG improvement, even …
Date: December 31, 2005
Creator: Stang, John H.
Object Type: Report
System: The UNT Digital Library
Void Coalescence Processes Quantified through Atomistic and Multiscale Simulation (open access)

Void Coalescence Processes Quantified through Atomistic and Multiscale Simulation

Simulation of ductile fracture at the atomic scale reveals many aspects of the fracture process including specific mechanisms associated with void nucleation and growth as a precursor to fracture and the plastic deformation of the material surrounding the voids and cracks. Recently we have studied void coalescence in ductile metals using large-scale atomistic and continuum simulations. Here we review that work and present some related investigations. The atomistic simulations involve three-dimensional strain-controlled multi-million atom molecular dynamics simulations of copper. The correlated growth of two voids during the coalescence process leading to fracture is investigated, both in terms of its onset and the ensuing dynamical interactions. Void interactions are quantified through the rate of reduction of the distance between the voids, through the correlated directional growth of the voids, and through correlated shape evolution of the voids. The critical inter-void ligament distance marking the onset of coalescence is shown to be approximately one void radius based on the quantification measurements used, independent of the initial separation distance between the voids and the strain-rate of the expansion of the system. No pronounced shear flow is found in the coalescence process.
Date: December 31, 2005
Creator: Rudd, R E; Seppala, E T; Dupuy, L M & Belak, J
Object Type: Article
System: The UNT Digital Library
Supported, Alkali-Promoted Cobalt Oxide Catalysts for NOx Removal from Coal Combustion Flue Gases (open access)

Supported, Alkali-Promoted Cobalt Oxide Catalysts for NOx Removal from Coal Combustion Flue Gases

A series of cobalt oxide catalysts supported on alumina ({gamma}-Al{sub 2}O{sub 3}) were synthesized with varying contents of cobalt and of added alkali metals, including lithium, sodium, potassium, rubidium, and cesium. Unsupported cobalt oxide catalysts and several cobalt oxide catalysts supported ceria (CeO{sub 2}) with varying contents of cobalt with added potassium were also prepared. The catalysts were characterized with UV-visible spectroscopy and were examined for NO{sub x} decomposition activity. The CoO{sub x}/Al{sub 2}O{sub 3} catalysts and particularly the CoO{sub x}/CeO{sub 2} catalysts show N{sub 2}O decomposition activity, but none of the catalysts (unsupported Co{sub 3}O{sub 4} or those supported on ceria or alumina) displayed significant, sustained NO decomposition activity. For the Al{sub 2}O{sub 3}-supported catalysts, N{sub 2}O decomposition activity was observed over a range of reaction temperatures beginning about 723 K, but significant (>50%) conversions of N{sub 2}O were observed only for reaction temperatures >900 K, which are too high for practical commercial use. However, the CeO{sub 2}-supported catalysts display N{sub 2}O decomposition rates similar to the Al{sub 2}O{sub 3}-supported catalysts at much lower reaction temperatures, with activity beginning at {approx}573 K. Conversions of >90% were achieved at 773 K for the best catalysts. Catalytic rates per cobalt atom …
Date: December 31, 2005
Creator: Argyle, Morris D.
Object Type: Report
System: The UNT Digital Library
Investigation of Efficiency Improvements During CO2 Injection in Hydraulically and Naturally Fractured Reservoirs (open access)

Investigation of Efficiency Improvements During CO2 Injection in Hydraulically and Naturally Fractured Reservoirs

None
Date: December 31, 2005
Creator: Schechter, David S.
Object Type: Report
System: The UNT Digital Library
Off-Highway Heavy Vehicle Diesel Efficiency Improvement and Emissions Reduction (open access)

Off-Highway Heavy Vehicle Diesel Efficiency Improvement and Emissions Reduction

Cummins Inc. is a world leader in the development and production of diesel engines for on-highway vehicles, off-highway industrial machines, and power generation units. Cummins Inc. diesel products cover a 50-3000 HP range. The power range for this project includes 174-750 HP to achieve EPA's Tier 3 emission levels of 4.0 NOx+NMHC gm/kW-hr and 0.2 PM gm/kWhr and Tier 4 Interim emission levels of 2.0 gm/kW-hr NOx and 0.02 gm/kW-hr PM. Cummins' anticipated product offerings for Tier 4 in this range include the following: QSB6.7, QSC8.3, QSL9, QSM11, QSX15, QSK19. (For reference, numerical values indicate engine displacement in liters, the letter designation ns indicate the product model). A summary of the EPA's mobile off-highway emissions requirements is given in Figure 1.
Date: December 31, 2005
Creator: Rumsey, Jennifer
Object Type: Report
System: The UNT Digital Library
Annual Site Environmental Report Calendar Year 2005 (open access)

Annual Site Environmental Report Calendar Year 2005

This report summarizes the environmental status of Ames Laboratory for calendar year 2005. It includes descriptions of the Laboratory site, its mission, the status of its compliance with applicable environmental regulations, its planning and activities to maintain compliance, and a comprehensive review of its environmental protection, surveillance and monitoring activities. Ames Laboratory is located on the campus of Iowa State University (ISU) and occupies 11 buildings owned by the Department of Energy (DOE). See the Laboratory's Web page at www.external.ameslab.gov for locations and Laboratory overview. The Laboratory also leases space in ISU owned buildings. In 2005, the Laboratory accumulated and disposed of waste under U.S. Environmental Protection Agency (EPA) issued generator numbers. All waste is handled accordingly to all applicable EPA, State, Local and DOE Orders. The most recent RCRA inspection was conducted by EPA Region VII in January 1999. The Laboratory received a notice of violation (NOV) which included five citations. There have been no inspections since then. The citations were minor and were corrected by the Laboratory within the time allocated by the EPA. See correspondence in Appendix D. The Laboratory was in compliance with all applicable federal, state, local and DOE regulations and orders in 2005. There …
Date: December 31, 2005
Creator: Kayser, Dan
Object Type: Report
System: The UNT Digital Library
Assessment of Distributed Energy Adoption in Commercial Buildings:Part 1: An Analysis of Policy, Building Loads, Tariff Design, andTechnology Development (open access)

Assessment of Distributed Energy Adoption in Commercial Buildings:Part 1: An Analysis of Policy, Building Loads, Tariff Design, andTechnology Development

Rapidly growing electricity demand brings into question theability of traditional grids to expand correspondingly while providingreliable service. An alternative path is the wider application ofdistributed energy resource (DER) that apply combined heat and power(CHP). It can potentially shave peak loads and satiate its growing thirstfor electricity demand, improve overall energy efficiency, and lowercarbon and other pollutant emissions. This research investigates a methodof choosing economically optimal DER, expanding on prior studies at theBerkeley Lab using the DER design optimization program, the DistributedEnergy Resources Customer Adoption Model (DER-CAM). DER-CAM finds theoptimal combination of installed equipment from available DERtechnologies, given prevailing utility tariffs, site electrical andthermal loads, and a menu of available equipment. It provides a globaloptimization, albeit idealized, that shows how the site energy loads canbe served at minimum cost by selection and operation of on-sitegeneration, heat recovery, and cooling. Utility electricity and gastariffs are key factors determining the economic benefit of a CHPinstallation, however often be neglected. This paper describespreliminary analysis on CHP investment climate in the U.S. and Japan. DERtechnologies, energy prices, and incentive measures has beeninvestigated.
Date: December 31, 2005
Creator: Zhou, Nan; Nishida, Masaru; Gao, Weijun & Marnay, Chris
Object Type: Article
System: The UNT Digital Library
RECENT REFERENCES: JANUARY 1, 2005 TO DECEMBER 31, 2005 (open access)

RECENT REFERENCES: JANUARY 1, 2005 TO DECEMBER 31, 2005

This document lists experimental references added to Nuclear Science References (NSR) during the period January 1, 2005 to December 31, 2005. The first section lists keynumbers and keywords sorted by mass and nuclide. The second section lists all references, ordered by keynumber.
Date: December 31, 2005
Creator: WINCHELL, D.F.
Object Type: Report
System: The UNT Digital Library
RECENT REFERENCES: OCTOBER 1, 2005 TO DECEMBER 31, 2005 (open access)

RECENT REFERENCES: OCTOBER 1, 2005 TO DECEMBER 31, 2005

This document lists experimental references added to Nuclear Science References (NSR) during the period October 1, 2005 to December 31, 2005. The first section lists keynumbers and keywords sorted by mass and nuclide. The second section lists all references, ordered by keynumber.
Date: December 31, 2005
Creator: WINCHELL, D.F.
Object Type: Report
System: The UNT Digital Library
Onboard Plasmatron Hydrogen Production for Improved Vehicles (open access)

Onboard Plasmatron Hydrogen Production for Improved Vehicles

A plasmatron fuel reformer has been developed for onboard hydrogen generation for vehicular applications. These applications include hydrogen addition to spark-ignition internal combustion engines, NOx trap and diesel particulate filter (DPF) regeneration, and emissions reduction from spark ignition internal combustion engines First, a thermal plasmatron fuel reformer was developed. This plasmatron used an electric arc with relatively high power to reform fuels such as gasoline, diesel and biofuels at an oxygen to carbon ratio close to 1. The draw back of this device was that it has a high electric consumption and limited electrode lifetime due to the high temperature electric arc. A second generation plasmatron fuel reformer was developed. It used a low-current high-voltage electric discharge with a completely new electrode continuation. This design uses two cylindrical electrodes with a rotating discharge that produced low temperature volumetric cold plasma., The lifetime of the electrodes was no longer an issue and the device was tested on several fuels such as gasoline, diesel, and biofuels at different flow rates and different oxygen to carbon ratios. Hydrogen concentration and yields were measured for both the thermal and non-thermal plasmatron reformers for homogeneous (non-catalytic) and catalytic reforming of several fuels. The technology was …
Date: December 31, 2005
Creator: Cohn, Daniel R.; Bromberg, Leslie & Hadidi, Kamal
Object Type: Report
System: The UNT Digital Library
Time-Lapse Modeling and Inversion of CO2 Saturation for Sequestration and Enhanced Oil Recovery (open access)

Time-Lapse Modeling and Inversion of CO2 Saturation for Sequestration and Enhanced Oil Recovery

None
Date: December 31, 2005
Creator: Meadows, Mark A.
Object Type: Report
System: The UNT Digital Library
Assessment of the Groundwater Protection Program Y-12 National Security Complex, Oak Ridge, Tennessee (open access)

Assessment of the Groundwater Protection Program Y-12 National Security Complex, Oak Ridge, Tennessee

The following report contains an assessment of the Y-12 Groundwater Protection Program (GWPP) for the Y-12 National Security Complex at the Oak Ridge Reservation, Tennessee.
Date: December 31, 2005
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Underground Coal Gasification Test Project (open access)

Underground Coal Gasification Test Project

None
Date: December 31, 2005
Creator: Dennis, D. Steve
Object Type: Report
System: The UNT Digital Library
Development of Polymer Gel Systems to Improve Volumetric Sweep and Reduce Producing Water/Oil Ratios (open access)

Development of Polymer Gel Systems to Improve Volumetric Sweep and Reduce Producing Water/Oil Ratios

Gelled polymer treatments are applied to oil reservoirs to increase oil production and to reduce water production by altering the fluid movement within the reservoir. This report describes the results of a 42-month research program that focused on the understanding of gelation chemistry and the fundamental mechanisms that alter the flows of oil and water in reservoir rocks after a gel treatment. Work was conducted on a widely applied system in the field, the partially hydrolyzed polyacrylamide-chromium acetate gel. Gelation occurs by network formation through the crosslinking of polyacrylamide molecules as a result of reaction with chromium acetate. Pre-gel aggregates form and grow as reactions between chromium acetate and polyacrylamide proceed. A rate equation that describes the reaction between chromium acetate and polymer molecules was regressed from experimental data. A mathematical model that describes the crosslinking reaction between two polymer molecules as a function of time was derived. The model was based on probability concepts and provides molecular-weight averages and molecular-weight distributions of the pre-gel aggregates as a function of time and initial system conditions. Average molecular weights of pre-gel aggregates were measured as a function of time and were comparable to model simulations. Experimental methods to determine molecular weight …
Date: December 31, 2005
Creator: Willhite, G. Paul; McCool, Stan; Green, Don W.; Cheng, Min & Chen, Feiyan
Object Type: Report
System: The UNT Digital Library
Direct Measurement of Mercury Reactions In Coal Power Plant Plumes (open access)

Direct Measurement of Mercury Reactions In Coal Power Plant Plumes

Recent field and pilot-scale results indicate that divalent mercury emitted from power plants may rapidly transform to elemental mercury within the power plant plumes. Simulations of mercury chemistry in plumes based on measured rates to date have improved regional model fits to Mercury Deposition Network wet deposition data for particular years, while not degrading model verification fits for remaining years of the ensemble. The years with improved fit are those with simulated deposition in grid cells in the State of Pennsylvania that have matching MDN station data significantly less than the model values. This project seeks to establish a full-scale data basis for whether or not significant reduction or oxidation reactions occur to mercury emitted from coal-fired power plants, and what numerical redox rate should apply for extension to other sources and for modeling of power plant mercury plumes locally, regionally, and nationally. Although in-stack mercury (Hg) speciation measurements are essential to the development of control technologies and to provide data for input into atmospheric fate and transport models, the determination of speciation in a cooling coal combustion plume is more relevant for use in estimating Hg fate and effects through the atmosphere. It is mercury transformations that may occur …
Date: December 31, 2005
Creator: Levin, Leonard
Object Type: Report
System: The UNT Digital Library
Development of Metal Substrate for Denox Catalysts and Particulate Trap (open access)

Development of Metal Substrate for Denox Catalysts and Particulate Trap

The objective of this project was to develop advanced metallic catalyst substrate materials and designs for use in off-highway applications. The new materials and designs will be used as catalyst substrates and diesel particulate traps. They will increase durability, reduce flow resistance, decrease time to light-off, and reduce cost relative to cordierite substrates. Metallic catalyst substrates are used extensively for diesel oxidation catalysts and have the potential to be used in other catalytic systems for diesel engines. Metallic substrates have many advantages over ceramic materials including improved durability and resistance to thermal shock and vibration. However, the cost is generally higher than cordierite. The most common foil material used for metallic substrates is FeCr Alloy, which is expensive and has temperature capabilities beyond what is necessary for diesel applications. The first task in the project was Identification and Testing of New Materials. In this task, several materials were analyzed to determine if a low cost substitute for FeCr Alloy was available or could be developed. Two materials were identified as having lower cost while showing no decrease in mechanical properties or oxidation resistance at the application temperatures. Also, the ability to fabricate these materials into a finished substrate was not …
Date: December 31, 2005
Creator: Pollard, Michael; Habeger, Craig; Frary, Megan; Haines, Scott; Fluharty, Amy; Dakhoul, Youssef et al.
Object Type: Report
System: The UNT Digital Library
Development of a Quantum Cascade Laser-Based Detector for Ammonia and Nitric Acid (open access)

Development of a Quantum Cascade Laser-Based Detector for Ammonia and Nitric Acid

We have developed a compact, robust, atmospheric trace gas detector based on mid-infrared absorption spectroscopy using pulsed quantum cascade (QC) lasers. The spectrometer is suitable for airborne measurements of ammonia, nitric acid, formaldehyde, formic acid, methane, nitrous oxide, carbon monoxide, nitrogen dioxide and other gases that have line-resolved absorption spectra in the mid-infrared spectral region. The QC laser light source operates near room temperature with thermal electric cooling instead of liquid nitrogen which has been previously required for semiconductor lasers in the mid-infrared spectral region. The QC lasers have sufficient output power so that thermal electric cooled detectors may be used in many applications with lower precision requirements. The instrument developed in this program has been used in several field campaigns from both the Aerodyne Mobile Laboratory and from the NOAA WP3 aircraft. The Phase II program has resulted in more than 10 archival publications describing the technology and its applications. Over 12 instruments based on this design have been sold to research groups in Europe and the United States making the program both a commercial as well as a technological success. Anticipated Benefits The development of a sensitive, cryogen-free, mid-infrared absorption method for atmospheric trace gas detection will have …
Date: December 31, 2005
Creator: Zahniser, Mark S.; Nelson, David D.; McManus, J. Barry; Shorter, Joanne H.; Herndon, Scott C. & Jimenez, Rodrigo
Object Type: Report
System: The UNT Digital Library