Sample records for stack gas particulate

  1. Cooler and particulate separator for an off-gas stack

    DOEpatents

    Wright, George T. (15 Cherry Hills Dr., Aiken, SC 29803)

    1992-01-01

    An off-gas stack for a melter comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes pervents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

  2. Cooler and particulate separator for an off-gas stack

    DOEpatents

    Wright, G.T.

    1991-04-08

    This report describes an off-gas stack for a melter, furnace or reaction vessel comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes prevents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

  3. STACK GAS REHEAT EVALUATION

    EPA Science Inventory

    The report gives results of technical and economic evaluations of stack gas reheat (SGR) following wet flue gas desulfurization (FGD) for coal-fired power plants. The evaluations were based on information from literature and a survey of FGD users, vendors, and architect/engineer ...

  4. FIELD EVALUATION OF AN AUTOISOKINETIC STACK PARTICULATE SAMPLING SYSTEM

    EPA Science Inventory

    The performance of a prototype autoisokinetic stack particulate sampling system, designed to maintain automatically isokinetic sampling conditions, was evaluated in field tests at stationary sources. Tests were conducted to determine the operating limits and characteristics of th...

  5. Diesel exhaust particulate trap with axially stacked filters

    SciTech Connect

    Smith, R. H.

    1983-12-06

    An elongated particulate trap is disclosed, to fit the area usually occupied by the vertical cylindrical muffler, as on a large diesel truck, consists of rings of axial flow filter elements and a disc-like axial flow end filter element stacked in a trap housing, having an exhaust inlet and outlet at opposite ends, so as to provide a central flow passage for entry of exhaust gases via the exhaust inlet and so as to define with the trap housing and exhaust passage in flow communication with the exhaust outlet. The filter elements are stacked in spaced apart relationship to each other whereby to provide an axial gap therebetween to allow radial flow on one face of the filter elements. The axial gaps are sealed alternately on inner and outer radial ends to define outlet and inlet passages, respectively and to force axial flow through the filter elements whereby particulates will be removed from the exhaust gases.

  6. A new method for the characterisation and quantitative speciation of base metal smelter stack particulates.

    PubMed

    Skeaff, James M; Thibault, Yves; Hardy, David J

    2011-06-01

    Base metal smelters may be a source of particulates containing metals of environmental concern released to the atmosphere. Knowledge of the quantitative chemical speciation of particulate releases from base metal smelters will be of value in smelter emission fingerprinting, site-specific risk assessments, predictions of the behaviour of smelter stack particulates released to the environment and in resolving liability issues related to current and historic releases. Accordingly, we have developed an innovative approach comprising bulk chemical analysis, a leaching procedure, X-ray diffraction analysis and scanning electron microscopy/electron probe microanalysis characterisation in a step-wise apportioning procedure to derive the quantitative speciation of particulate samples from the stacks of three copper smelters designated as A, B and C. For the A smelter stack particulates, the major calculated percentages were 29 CuSO(4), 20 ZnSO(4).H(2)O, 13 (Cu(0.94)Zn(0.06))(2)(AsO(4))(OH), 11 PbSO(4) and four As(2)O(3). For the B smelter stack particulates, the primary calculated percentages were 20 ZnSO(4).H(2)O, 20 PbSO(4), 12 CuSO(4) and nine As(2)O(3). Finally, we calculated that the C smelter stack particulates mostly comprised 34 ZnSO(4).H(2)O, 19 (Cu(0.84)Zn(0.16))(AsO(3)OH), 11 PbSO(4), 10 As(2)O(3) and nine Zn(3)(AsO(4))(2). Between 56% and 67% by weight of the smelter stack particulates, including the As, was soluble in water. For these and other operations, the data and approach may be useful in estimating metals partitioning among water, soil and sediment, as well as predictions of the effects of the stack particulates released to the environment. PMID:20676929

  7. Stack Gas Scrubber Makes the Grade

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Describes a year long test of successful sulfur dioxide removal from stack gas with a calcium oxide slurry. Sludge disposal problems are discussed. Cost is estimated at 0.6 mill per kwh not including sludge removal. A flow diagram and equations are included. (GH)

  8. Gas and solid particulate material heat exchanger

    SciTech Connect

    Kreisberg, A.J.; Warshawsky, J.

    1986-12-16

    This patent describes an apparatus for carrying out heat exchange between a gas and solid particulate material comprising a casing having an upper inlet for particulate material and a lower outlet for particulate material and a lower grate mounted in the casing extending from the upper inlet to the lower outlet for supporting a bed of particulate material for movement from the inlet to the outlet along the lower grate. A means defines an upper grate mounted in the casing and is spaced from the lower grate including generally vertically oriented slats, each spaced from and positioned below a preceding slat in the direction from the inlet toward the outlet for defining the top of the bed of material while permitting the bed of material to expand. The casing includes an inlet for gas on one side of the casing and an outlet for gas on the other side of the casing whereby gas flows from the inlet through the lower grate, the bed of material and through the upper grate to the outlet for gas for carrying out heat exchange between the gas and the solid particulate material. Each of the slats is perforated to permit gas and fine material to pass therethrough while retaining the bed of material on the lower grate.

  9. PROCEEDINGS: SEMINAR ON IN-STACK PARTICLE SIZING FOR PARTICULATE CONTROL DEVICE EVALUATION

    EPA Science Inventory

    The proceedings document discussions during an EPA/IERL-RTP-sponsored seminar on In-stack Particle Sizing for Particulate Control Device Evaluation. The seminar, organized by IERL-RTP's Process Measurements Branch, was held at IERL-RTP in North Carolina on December 3 and 4, 1975....

  10. Removal of Sulfur from Natural Gas to Reduce Particulate Matter Emission from a Turbine Engine

    NASA Astrophysics Data System (ADS)

    Spang, Brent Loren

    The present work investigates the effect of natural gas fuel sulfur on particulate emissions from stationary gas turbine engines used for electricity generation. Fuel sulfur from standard line gas was scrubbed using a system of fluidized reactor beds containing a specially designed activated carbon purpose built for sulfur absorption. A sulfur injection system using sonic orifices was designed and constructed to inject methyl mercaptan into the scrubbed gas stream at varying concentrations. Using these systems, particulate emissions created by various fuel sulfur levels between 0 and 8.3 ppmv were investigated. Particulate samples were collected from a Capstone C65 microturbine generator system using a Horiba MDLT-1302TA micro dilution tunnel and analyzed using a Horiba MEXA-1370PM particulate analyzer. In addition, ambient air samples were collected to determine incoming particulate levels in the combustion air. The Capstone C65 engine air filter was also tested for particulate removal efficiency by sampling downstream of the filter. To further differentiate the particulate entering the engine in the combustion air from particulate being emitted from the exhaust stack, two high efficiency HEPA filters were installed to eliminate a large portion of incoming particulate. Variable fuel sulfur testing showed that there was a strong correlation between total particulate emission factor and fuel sulfur concentration. Using eleven variable sulfur tests, it was determined that an increase of 1 ppmv fuel sulfur will produce an increase of approximately 3.2 microg/m3 total particulate. Also, the correlation also predicted that, for this particular engine, the total particulate emission factor for zero fuel sulfur was approximately 19.1 microg/m3. With the EC and OC data removed, the correlation became 3.1 microg/m3 of sulfur particulate produced for each ppmv of fuel sulfur. The correlation also predicted that with no fuel sulfur present, 6.6 microg/m3 of particulate will be produced by sulfur passing through the engine air filter.

  11. Simultaneous stack-gas scrubbing and waste water treatment

    NASA Technical Reports Server (NTRS)

    Poradek, J. C.; Collins, D. D.

    1980-01-01

    Simultaneous treatment of wastewater and S02-laden stack gas make both treatments more efficient and economical. According to results of preliminary tests, solution generated by stack gas scrubbing cycle reduces bacterial content of wastewater. Both processess benefit by sharing concentrations of iron.

  12. Method for removing particulate matter from a gas stream

    DOEpatents

    Postma, Arlin K. (Benton City, WA)

    1984-01-01

    Particulate matter is removed from a stream of pressurized gas by directing the stream of gas upwardly through a bed of porous material, the porous bed being held in an open ended container and at least partially submerged in liquid. The passage of the gas through the porous bed sets up a circulation in the liquid which cleans the particulate matter from the bed.

  13. Process for off-gas particulate removal and apparatus therefor

    DOEpatents

    Carl, D.E.

    1997-10-21

    In the event of a breach in the off-gas line of a melter operation requiring closure of the line, a secondary vessel vent line is provided with a particulate collector utilizing atomization for removal of large particulates from the off-gas. The collector receives the gas containing particulates and directs a portion of the gas through outer and inner annular channels. The collector further receives a fluid, such as water, which is directed through the outer channel together with a second portion of the particulate-laden gas. The outer and inner channels have respective ring-like termination apertures concentrically disposed adjacent one another on the outer edge of the downstream side of the particulate collector. Each of the outer and inner channels curves outwardly away from the collector`s centerline in proceeding toward the downstream side of the collector. Gas flow in the outer channel maintains the fluid on the channel`s wall in the form of a ``wavy film,`` while the gas stream from the inner channel shears the fluid film as it exits the outer channel in reducing the fluid to small droplets. Droplets formed by the collector capture particulates in the gas stream by one of three mechanisms: impaction, interception or Brownian diffusion in removing the particulates. The particulate-laden droplets are removed from the fluid stream by a vessel vent condenser or mist eliminator. 4 figs.

  14. PARTICULATE HOT GAS STREAM CLEANUP TECHNICAL ISSUES

    SciTech Connect

    NONE

    1999-05-01

    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report includes summaries of analyses performed on particulate samples from Sierra Pacific Power Company's Pinon Pine Power Project. This report also reviews the status of the HGCU data bank of ash and char characteristics, and plans for enhancing the data bank with interactive querying of measured particulate properties. Task 1 plans for the remainder of the project include completion and delivery of the HGCU data bank. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter included preliminary testing of two materials. One material tested was the soft candle filter manufactured by CGC and supplied by ABB. The other material was N610/mullite manufactured by Albany International (AIT).

  15. Process for off-gas particulate removal and apparatus therefor

    DOEpatents

    Carl, Daniel E. (Orchard Park, NY)

    1997-01-01

    In the event of a breach in the off-gas line of a melter operation requiring closure of the line, a secondary vessel vent line is provided with a particulate collector utilizing atomization for removal of large particulates from the off-gas. The collector receives the gas containing particulates and directs a portion of the gas through outer and inner annular channels. The collector further receives a fluid, such as water, which is directed through the outer channel together with a second portion of the particulate-laden gas. The outer and inner channels have respective ring-like termination apertures concentrically disposed adjacent one another on the outer edge of the downstream side of the particulate collector. Each of the outer and inner channels curves outwardly away from the collector's centerline in proceeding toward the downstream side of the collector. Gasflow in the outer channel maintains the fluid on the channel's wall in the form of a "wavy film," while the gas stream from the inner channel shears the fluid film as it exits the outer channel in reducing the fluid to small droplets. Droplets formed by the collector capture particulates in the gas stream by one of three mechanisms: impaction, interception or Brownian diffusion in removing the particulates. The particulate-laden droplets are removed from the fluid stream by a vessel vent condenser or mist eliminator.

  16. Particulate hot gas stream cleanup technical issues

    SciTech Connect

    NONE

    1998-09-01

    This is the tenth in a series of quarterly reports describing the activities performed under Contract No. DE-AC21-94MC31160. Analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic bed filter elements. Task I is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task I during the past quarter, analyses were performed on a particulate sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota Energy and Environmental Research Center. Analyses are in progress on ash samples from the Advanced Particulate Filter (APF) at the Pressurized Fluidized-Bed Combustor (PFBC) that was in operation at Tidd and ash samples from the Pressurized Circulating Fluid Bed (PCFB) system located at Karhula, Finland. A site visit was made to the Power Systems Development Facility (PSDF) to collect ash samples from the filter vessel and to document the condition of the filter vessel with still photographs and videotape. Particulate samples obtained during this visit are currently being analyzed for entry into the Hot Gas Cleanup (HGCU) data base. Preparations are being made for a review meeting on ash bridging to be held at Department of Energy Federal Energy Technology Center - Morgantown (DOE/FETC-MGN) in the near future. Most work on Task 2 was on hold pending receipt of additional funds; however, creep testing of Schumacher FT20 continued. The creep tests on Schumacher FT20 specimens just recently ended and data analysis and comparisons to other data are ongoing. A summary and analysis of these creep results will be sent out shortly. Creep testing of two Refractron 326 specimens is now in progress. Among the tasks expected to be completed this quarter are analysis of the creep data obtained thus far, microstructural analysis of Refractron 326 and Schumacher FT20, definition of bending loads on candle filters, and characterization of additional candle filters from Karhula.

  17. Stack Gas Heat Recovery from 100 to 1200 HP Boilers

    E-print Network

    Judson, T. H.

    1980-01-01

    STACK GAS HEAT RECOVERY FROM 100 TO 1200 HP BOILERS Thomas H. Judson Peabody Gordon-Piatt, Inc. Walnut Creek, CA ABSTRACT With newspaper reports of March 1980 fuel price increases at as much as a 110% annualized rate, ener~y users...quidboller I I more closely at boiler stack gas heat recovery for heat recovery unit, trade marked the HEATMIZER. THe energy conservation ip 1975. unit was "packaged" as a system for ease of applic L Our investigation verified by initial installa tion...

  18. Simultaneous stack gas scrubbing wastewater purification

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Variations of a process for removing sulfur dioxide from stack gases and using it to treat municipal waste water are described. The once-through system lowers the pH of the scrubbing water from minor depressions to a pH of about 2.5 under certain conditions. A recycle system uses iron for catalytic oxidation of sulfurous acid to sulfuric acid allowing very large amounts of sulfur dioxide to be absorbed in a small portion of water. The partial recycle system uses municipal wastewater and iron as a scrubbing medium, followed by neutralization of the wastewater with lime to produce an iron hydroxide precipitation which, when removed, produces tertiary quality treated wastewater. The SO2 scrubber is described, test results are analyzed, and a preliminary capital cost estimate for the three processes is included.

  19. Energy Economizer for Low Temperature Stack Gas: A Case Study

    E-print Network

    Tipton, J. A.

    1979-01-01

    , the burner air supply is preheated by passing through the heat exchanger. Sensitive design problems that had to be resolved were: Overall cost-effectiveness; below dew point cooling of stack gas causing acid corrosion; and selection of an effective heat...

  20. Size distribution and chemical composition of particulate matter stack emissions in and around a copper smelter

    NASA Astrophysics Data System (ADS)

    González-Castanedo, Yolanda; Moreno, Teresa; Fernández-Camacho, Rocío; Sánchez de la Campa, Ana María; Alastuey, Andrés; Querol, Xavier; de la Rosa, Jesús

    2014-12-01

    This paper reports on results from a multi-sampling campaign (stack, fugitive emissions and ambient air measurements) to characterise the geochemical signature of metal and metalloid particles emitted from one of the largest Cu-smelters in the world (in Huelva, SW Spain). Exceptionally high concentrations of very fine particles (<0.33 ?m) bearing As, Cd, Pb, Cu, Bi, Zn (?>100 ?g m-3) are emitted from the Flash Smelting Furnaces, but high levels are also emitted by the other main chimney stacks, namely Refining Furnaces, Sulphuric Plant, Converters Unit, and Crushing Plant. Enhanced concentrations of the same elements are also observed in ground measurements near the industrial complex. During the sampling campaign, the presence of plumes from the Cu-smelter over the nearby city of Huelva was identified based on increased concentrations of gaseous pollutants, particulate metals and ultrafine particle numbers (PN). The results demonstrate that the Cu-smelter is an important source of inhalable toxic elements carried by fine airborne particles. The pollution abatement systems applied so far appear to be relatively ineffective in preventing metalliferous air pollution events, potentially increasing health risks to local and regional populations.

  1. PARTICULATE HOT GAS STREAM CLEANUP TECHNICAL ISSUES

    SciTech Connect

    D.H. Pontius

    1999-08-30

    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report reviews the status of the HGCU data bank of ash and char characteristics, including the interactive querying of measured particulate properties. Task 1 plans for the remainder of the project include completion and delivery of the HGCU data bank, and issuance of a comprehensive final report on activities conducted under Task 1. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter included preliminary testing of two materials. One material tested was the soft candle filter manufactured by CGC and supplied by ABB. The other material was N610/mullite manufactured by Albany International (AIT).

  2. Particulate Hot Gas Stream Cleanup Technical Issues

    SciTech Connect

    None

    1998-08-31

    This is the fifteenth quarterly report describing the activities performed under Contract No. DE-AC21-94MC31160. The analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance studied under this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. Task 1 is designed to generate a data bank of the key characteristics of ashes collected from operating advanced particle filters (APFs) and to relate these ash properties to the operation and performance of these filters and their components. APF operations have also been limited by the strength and durability of the ceramic materials that have served as barrier filters for the capture of entrained HGCU ashes. Task 2 concerns testing and failure analyses of ceramic filter elements currently used in operating APFs and the characterization and evaluation of new ceramic materials. Task 1 research activities during the past quarter included characterizations of samples collected during a site visit on May 18 to the Department of Energy / Southern Company Services Power Systems Development Facility (PSDF) and a particulate sample collected in the Westinghouse filter at Sierra Pacific Power Company?s Piñon Pine Power Project. Analysis of this Piñon Pine sample is ongoing: however, this report contains the results of analyses completed to date. Significant accomplishments were achieved on the HGCU data bank during this reporting quarter. The data bank was prepared for presentation at the Advanced Coal-Based Power and Environmental Systems ?98 Conference scheduled for July, 1998. Task 2 work during the past quarter consisted of testing two Dupont PRD-66C candle filters, one McDermott ceramic composite candle filter, one Blasch 4-270 candle filter, and one Specific Surface cordierite candle filter. Tensile and thermal expansion testing is complete and the rest of the testing is in progress. Also, some 20-inch long Dupont PRD-66C, McDermott ceramic composite, and Westinghouse Techniweave candle filters have been received for testing after their exposure to the gasification environment. One as-manufactured and one exposed element was received of each material and specimens are currently being machined from these candles.

  3. Rotary device for removing particulates from a gas stream

    NASA Technical Reports Server (NTRS)

    Collins, Jr., Earl R. (Inventor)

    1992-01-01

    A rotary particulate separator for removing particulates from a pressurized gas stream such as that emanating from a reactor vessel is disclosed which precharges the particles in the gas stream, and then utilizes the charge on the particles to induce them from the main flow path through an airblock and into the rotary particulate separator. The rotor of the rotary particulate separator has polarized plates which use a first charge opposite that on the charged particles to attract the particles as they enter the rotation chamber, and then use a second charge of the same polarity as the charge on the charged particles to release the particles into a control gas flow vortex which draws the particles radially inwardly into an exit aperture contained in the center of one of the rotor segments and out from the device. Pressure letdown devices are used to drop the pressure of both the control gas flow exiting the separator with the particles and the cleaned gas stream.

  4. CAPSULE REPORT: BAHCO FLUE GAS DESULFURIZATION AND PARTICULATE REMOVAL SYSTEM

    EPA Science Inventory

    This capsule report describes a Research-Cottrell/Bahco scrubber module for sulfur dioxide and particulate emission control located at the central heat plant of Rickenbacker Air Force Base. he report also describes flue gas desulfurization technology using any fuel, including hig...

  5. Prototype particle stack sampler with virtual impactor nozzle and microcomputer calculating/display system. [H5 Stack Particulate Sampler/Calculator

    SciTech Connect

    Elder, J.C.; Littlefield, L.G.; Tillery, M.I.; Ettinger, H.J.

    1981-07-01

    A prototype particle stack sampler (PPSS) was developed to improve on the existing Environmental Protection Agency (EPA) Method 5 sampling apparatus. Primary features of the stack sampler were: higher sampling rate; display (on demand) of all required variables and calculated values by a microcomputer-based calculating and display system; continuous stack gas moisture determination; a virtual impactor nozzle designed to separate fine and coarse particle fractions; a variable-area inlet to maintain isokinetic sampling conditions; and stainless-steel components rather than the glass specified by EPA Method 5. The calculating and display system incorporates a single component microcomputer, a single-chip 16-channel analog-to-digital converter, a programmable keyboard/display interface, and liquid crystal displays. The scientific calculations capability and associated display have been incorporated to perform and display the results of 24 equations. These results allow the operator to maintain isokinetic sampler probe temperatures, to maintain proper flow through the sampler probe, and to make sampler probe position changes when necessary. The basic sampling technique of particle collection on preweighed filters was retained; however, versatility in the form of optional in-stack filters and general modernization of the stack sampler have been provided in the prototype design. Laboratory testing with monodisperse dye aerosols has shown the present variable-inlet, virtual impactor nozzle to have significant wall losses and a collection efficiency that is less than 77%. This is primarily due to lack of symmetry in this rectangular jet impactor and short transition lengths dictated by physical design constraints (required by passage of the nozzle through a 7.6-cm (3-in.) diameter stack port). Electronic components have shown acceptable service in laboratory testing.

  6. TECHNIQUES TO MEASURE VOLUMETRIC FLOW AND PARTICULATE CONCENTRATION IN STACKS WITH CYCLONIC FLOW

    EPA Science Inventory

    The study determined that an in-stack venturi can accurately measure volumetric flow in stacks with a severe cyclonic flow profile. The design requirements of the venturi are described in the report. The report also describes a low head loss, egg crate-shaped device that effectiv...

  7. Direct sampling of gas and particulates from electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Harding, Thomas W.; Kim, Yong W.

    1982-05-01

    During a given arc furnace heat for melting of scrap steel charges and subsequent steel making, considerable amounts of particulates are produced, varying in composition, size distribution and production rates corresponding to several distinct stages of the heat. In an effort to develop a detailed model for the particle production mechanisms, a new program for direct sampling of the furnace gas and particulates from the interior of the furnace has been devised and successfully implemented. It consists of a new high temperature sampling tube, capable of withstanding temperatures up to 1900 C for an indefinite period of time, and an experimental protocol designed to extract certain specific information necessary for development of a theoretical model. The results from two complete runs are described in detail. A theoretical model has been formulated, as guided by the measurements, which facilitates realistic predictions of the growth rate and elemental compositon of the particulates.

  8. Particulate exhaust emissions from an experimental combustor. [gas turbine engine

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Ingebo, R. D.

    1975-01-01

    The concentration of dry particulates (carbon) in the exhaust of an experimental gas turbine combustor was measured at simulated takeoff operating conditions and correlated with the standard smoke-number measurement. Carbon was determined quantitatively from a sample collected on a fiberglass filter by converting the carbon in the smoke sample to carbon dioxide and then measuring the volume of carbon dioxide formed by gas chromatography. At a smoke of 25 (threshold of visibility of the smoke plume for large turbojets) the carbon concentration was 2.8 mg carbon/cu m exhaust gas, which is equivalent to an emission index of 0.17 g carbon/kg fuel.

  9. Engine exhaust particulate and gas phase contributions to vascular toxicity.

    PubMed

    Campen, Matthew; Robertson, Sarah; Lund, Amie; Lucero, Joann; McDonald, Jacob

    2014-05-01

    Cardiovascular health effects of near-roadway pollution appear more substantial than other sources of air pollution. The underlying cause of this phenomenon may simply be concentration-related, but the possibility remains that gases and particulate matter (PM) may physically interact and further enhance systemic vascular toxicity. To test this, we utilized a common hypercholesterolemic mouse model (Apolipoprotein E-null) exposed to mixed vehicle emission (MVE; combined gasoline and diesel exhausts) for 6?h/d?×?50?d, with additional permutations of removing PM by filtration and also removing gaseous species from PM by denudation. Several vascular bioassays, including matrix metalloproteinase-9 protein, 3-nitrotyrosine and plasma-induced vasodilatory impairments, highlighted that the whole emissions, containing both particulate and gaseous components, was collectively more potent than MVE-derived PM or gas mixtures, alone. Thus, we conclude that inhalation of fresh whole emissions induce greater systemic vascular toxicity than either the particulate or gas phase alone. These findings lend credence to the hypothesis that the near-roadway environment may have a more focused public health impact due to gas-particle interactions. PMID:24730681

  10. Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    Wey, Chown Chou (Compiler)

    1999-01-01

    In response to the National Research Council (NRC) recommendations, the Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines was organized by the NASA Lewis Research Center and held on July 29-30, 1997 at the Ohio Aerospace Institute in Cleveland, Ohio. The objective is to develop consensus among experts in the field of aerosols from gas turbine combustors and engines as to important issues and venues to be considered. Workshop participants' expertise included engine and aircraft design, combustion processes and kinetics, atmospheric science, fuels, and flight operations and instrumentation.

  11. PARTICULATE HOT GAS STREAM CLEANUP TECHNICAL ISSUES

    SciTech Connect

    None

    1999-02-26

    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report includes a description of a device developed to harden a filter cake on a filter element so that the element and cake can subsequently be encapsulated in epoxy and studied in detail. This report also reviews the status of the HGCU data base of ash and char characteristics. Task 1 plans for the remainder of the project include characterization of additional samples collected during site visits to the Department of Energy/Southern Company Services Power Systems Development Facility (PSDF), encapsulation of an intact filter cake from the PSDF, and completion and delivery of the HGCU data bank. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter consisted of hoop tensile and axial compressive stress-strain responses of McDermott ceramic composite and hoop tensile testing of Techniweave candle filters as-manufactured and after exposure to the gasification environment.

  12. Particulate hot gas stream cleanup technical issues

    SciTech Connect

    NONE

    1998-09-01

    This is the thirteenth quarterly report describing the activities performed under Contract No. DE-AC21-94MC31160. The analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance studied under this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters and their components. APF operations have also been limited by the strength and durability of the ceramic materials that have served as barrier filters for the capture of entrained HGCU ashes. Task 2 concerns testing and failure analyses of ceramic filter elements currently used in operating APFs and the characterization and evaluation of new ceramic materials. Task I research activities during the past quarter included characterizations of additional ash samples from Pressurized Fluidized-Bed Combustion (PFBC) facilities to the HGCU data base. Task I plans for the next quarter include characterization of samples collected during a site visit on January 20 to the Department of Energy / Southern Company Services Power Systems Development Facility (PSDF). Further work on the HGCU data base is also planned. Task 2 work during the past quarter included creep testing of a Coors P- I OOA- I specimen machined from Candle FC- 007 after 1166 hours in-service at the Karhula Pressurized Circulating Fluid Bed (PCFB) facility. Samples are currently in preparation for microstructural evaluations of Coors P-IOOA-I.Sixteen cordierite rings manufactured by Specific Surfaces were received for testing. Three of the specimens were exposed to the PFBC environment at the PSDF. These specimens are currently being machined for testing.

  13. Remote and cross-stack measurement of stack gas concentrations using a mobile FT-IR system.

    PubMed

    Herget, W F

    1982-02-15

    The EPA remote optical sensing of emissions (ROSE) system consists of a commercial FT-IR system and associated components installed in a van. The ROSE system was recently used to make both single-ended measurements of the emission spectra of the gas plume exiting a cement plant smokestack and also cross-stack measurements of the absorption spectra of the stack gases. The stack gases were also analyzed by conventional extractive techniques. The species NO, CO, CO(2), and NH(3) were observed in emission and absorption at concentrations of the order of 400, 50, 120,000, and 10 ppm, respectively. The species HC1, H(2)CO, HF, and SO(2) (typical concentrations of 20, 6, 0.5, and 40 ppm, respectively) were observed in absorption. Stack plume temperatures determined from the emission spectra agreed with in-stack temperature measurements to within +/-10%; concentration measurements agreed to within about +/-20%. This paper discusses the measurement and calibration procedures and shows the spectral signatures for the various species observed in the emission and absorption measurements. PMID:20372510

  14. Particulate Matter Stack Emission Compliance Test Procedure for Fuel Burning Units.

    ERIC Educational Resources Information Center

    West Virginia Air Pollution Control Commission, Charleston.

    This publication details the particulate matter emissions test procedure that is applicable for conducting compliance tests for fuel burning units required to be tested under Sub-section 7 of Regulation II (1972) as established by the state of West Virginia Air Pollution Control Commission. The testing procedure is divided into five parts:…

  15. Characterization of cotton gin total particulate matter emissions based on EPA stack sampling methodologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A project to characterize cotton gin emissions in terms of stack sampling was conducted during the 2008 through 2011 ginning seasons. The impetus behind the project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. EPA AP-42 emission factors ar...

  16. Characteristics of a four nozzle, slotted mixing stack with slanted shroud, gas eductor system

    Microsoft Academic Search

    N. D. Pritchard Jr.

    1983-01-01

    Cold flow tests were conducted on a four nozzle gas educator system to evaluate the system's performance using a slotted mixing stack with slanted shroud and diffuser rings. The stack length-to-diameter ratios evaluated were 1.5 and 2.25. The nozzles were constructed with a ratio of total area or primary flow to area of mixing stack of 2.5. One set of

  17. A new approach for biological online testing of stack gas condensate from municipal waste incinerators.

    PubMed

    Elsner, Dorothea; Fomin, Anette

    2002-01-01

    A biological testing system for the monitoring of stack gas condensates of municipal waste incinerators has been developed using Euglena gracilis as a test organism. The motility, velocity and cellular form of the organisms were the endpoints, calculated by an image analysis system. All endpoints showed statistically significant changes in a short time when organisms were exposed to samples collected during combustion situations with increased pollutant concentrations. The velocity of the organisms proved to be the most appropriate endpoint. A semi-continuous system with E. gracilis for monitoring stack gas condensate is proposed, which could result in an online system for testing stack gas condensates in the future. PMID:12214718

  18. Characteristics of a four nozzle, slotted mixing stack with slanted shroud, gas eductor system

    NASA Astrophysics Data System (ADS)

    Pritchard, N. D., Jr.

    1983-09-01

    Cold flow tests were conducted on a four nozzle gas educator system to evaluate the system's performance using a slotted mixing stack with slanted shroud and diffuser rings. The stack length-to-diameter ratios evaluated were 1.5 and 2.25. The nozzles were constructed with a ratio of total area or primary flow to area of mixing stack of 2.5. One set of straight nozzles and another set, tilted at 15 degrees, were used. Secondary and tertiary pumping coefficients, and mixing stack pressure distributions were used to evaluate the slant shrouded mixing stacks. Pumping performance of the four straight nozzle shrouded system was found to be comparable to previously tested unshrouded models, showing no specific advantages. Pumping performance of the tilted nozzles and slanted shroud showed an improvement over the straight shroud model, with a noticeable increase in the tertiary pumping.

  19. Gas-particulate separator with pulse-jet cleanable filter elements

    Microsoft Academic Search

    R. A. Graff; M. D. Perry

    1981-01-01

    A vortical-type separator for removing from the gas stream suspended particulates present in the gas stream has an internally generated scavenging gas flow and a pulse jet system for cleaning scavenging gas filter elements. The separator has two or more conduits that are coaxially positioned with an annular clearance at their ends. A gas swirl device creates a swirling motion,

  20. Exposure assessment of particulates of diesel and natural gas fuelled buses in silico.

    PubMed

    Pietikäinen, Mari; Oravisjärvi, Kati; Rautio, Arja; Voutilainen, Arto; Ruuskanen, Juhani; Keiski, Riitta L

    2009-12-15

    Lung deposition estimates of particulate emissions of diesel and natural gas (CNG) fuelled vehicles were studied by using in silico methodology. Particulate emissions and particulate number size distributions of two Euro 2 petroleum based diesel buses and one Euro 3 gas bus were measured. One of the petroleum based diesel buses used in the study was equipped with an oxidation catalyst on the vehicle (DI-OC) while the second had a partial-DPF catalyst (DI-pDPF). The third bus used was the gas bus with an oxidation catalyst on the vehicle (CNG-OC). The measurements were done using a transient chassis dynamometer test cycle (Braunschweig cycle) and an Electric Low Pressure Impactor (ELPI) with formed particulates in the size range of 7 nm to 10 microm. The total amounts of the emitted diesel particulates were 88-fold for DI-OC and 57-fold for DI-pDPF compared to the total amount of emitted CNG particulates. Estimates for the deposited particulates were computed with a lung deposition model ICRP 66 using in-house MATLAB scripts. The results were given as particulate numbers and percentages deposited in five different regions of the respiratory system. The percentages of particulates deposited in the respiratory system were 56% for DI-OC, 51% for DI-pDPF and 77% for CNG-OC of all the inhaled particulates. The result shows that under similar conditions the total lung dose of particulates originating from petroleum diesel fuelled engines DI-OC and DI-pDPF was more than 60-fold and 35-fold, respectively, compared to the lung dose of particulates originating from the CNG fuelled engine. The results also indicate that a majority (35-50%) of the inhaled particulates emitted from the tested petroleum diesel and CNG engines penetrate deep into the unciliated regions of the lung where gas-exchange occurs. PMID:19828175

  1. Evaluation of gas cooling for pressurized phosphoric acid fuel cell stacks

    NASA Astrophysics Data System (ADS)

    Farooque, M.; Skok, A. J.; Maru, H. C.; Kothmann, R. E.; Harry, R. W.

    Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas cooling has already been demonstrated in atmospheric pressure stacks. This paper presents theoretical and experimental investigation of gas cooling for pressurized PAFC. Two approaches to gas cooling, Distributed Gas Cooling (DIGAS) and Separated Gas Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

  2. Evaluation of gas cooling for pressurized phosphoric acid fuel cell stacks

    NASA Technical Reports Server (NTRS)

    Farooque, M.; Skok, A. J.; Maru, H. C.; Kothmann, R. E.; Harry, R. W.

    1983-01-01

    Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas cooling has already been demonstrated in atmospheric pressure stacks. This paper presents theoretical and experimental investigation of gas cooling for pressurized PAFC. Two approaches to gas cooling, Distributed Gas Cooling (DIGAS) and Separated Gas Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

  3. Optical backscatter probe for sensing particulate in a combustion gas stream

    DOEpatents

    Parks, James E; Partridge, William P

    2013-05-28

    A system for sensing particulate in a combustion gas stream is disclosed. The system transmits light into a combustion gas stream, and thereafter detects a portion of the transmitted light as scattered light in an amount corresponding to the amount of particulates in the emissions. Purge gas may be supplied adjacent the light supply and the detector to reduce particles in the emissions from coating or otherwise compromising the transmission of light into the emissions and recovery of scattered light from the emissions.

  4. Characteristics and photochemical potentials of volatile organics emission from stack exhaust gas of industrial processes

    SciTech Connect

    Hsu, Y.C.; Tsai, J.H.; Lin, T.C.; Cheng, C.C.; Huang, Y.H.

    1999-07-01

    The main objective of this project was to measure the main volatile organic compounds (VOCs) in stack gas from the downstream petrochemical plants. Six pollution sources of industrial processes, including Acrylonitrile-Butadiene-Styrene (ABS), Vinyl Chloride(VC), Polyvinyl Chloride (PVC), Acrylic Resin, para-Terephthalic Acid (PTA) and Polyurethane (PU) synthetic manufacturing processes, were measured by using USEPA Method 18. The concentration and emission rate database of twenty-seven VOCs has been established. Fifty-two selected stacks were sampled and analyzed for VOCs. Analysis of emission factors and characteristics of the twenty-seven VOCs in these stacks show that the emission characteristics are various among different industrial processes. The order of the single-stack VOCs average emission factor are ABS (1.109 lbs VOCs/ton-ABS; 22 stacks) {gt} Acrylic Resin (0.651 lbs VOCs/ton-acrylic resin; 7 stacks) {gt} PU Synthetic (0.606 lbs VOCs/ton-PU synthetic; 4 stacks) {gt} PTA (0.054 lbs VOCs/ton-PTA; 4 stacks) {gt} PVC (0.014 lbs VOCs/ton-PVC; 11 stacks) {gt} VC ({lt} 0.001; 4 stacks) manufacturing processes. The emission factors of VOC in AP-42 database for the processes of are 5 to 40 times higher than those of VOCs in this research. Because of the equipment of pollutant control setting up before the emitted exhaust gas, their average emission factors in these measured processes are almost lower than those of VOCs in AP-42 database. Compared with the characteristics of VOCs, there is little similarity in VOC characteristics for the stacks of six processes between the results from this research and the data from US EPA SPECIATE data system. Furthermore, according to maximum incremental reactivities (MIR) of VOCs probed into photochemical reaction potentials, the results show that those of PTA manufacturing process have an ozone formation potential of 2.33 g O{sub 3}/g VOCs, which is higher than other processes.

  5. FACTORS INFLUENCING THE DEPOSITION OF A COMPOUND THAT PARTITIONS BETWEEN GAS AND PARTICULATE PHASES

    EPA Science Inventory

    How will atmospheric deposition behave for a compound when it reversibly sorbs between gas and atmospheric particulate phases? Two factors influence the answer. What physical mechanisms occur in the sorption process? What are the concentration and composition of atmospheric par...

  6. Flue Gas Conditioning to Reduce Particulate Emissions in Industrial Coal-Fired Boilers

    E-print Network

    Miller, B.; Keon, E.

    1980-01-01

    Chemical technology has been used successfully to solve many of the operational and emissions problems that result from burning coal. This paper describes the use of blended chemical flue gas conditioners to significantly reduce particulate...

  7. Automatic system to control radial gas-flow distribution parameters in the blast-furnace stack

    Microsoft Academic Search

    I. A. Rylov; M. M. Shmonin; V. A. Makarychev; V. M. Yanchevskii; O. R. Basargin; A. P. Kalinin

    1980-01-01

    and instruments for controlling the distribution of the gas flow across the stack of blast furnaces. This is because the proportion of indirectly reduced iron represents a significant part of the material and heat balances in blast-furnace smelting, determining the technicoeconomic indices of furnace operation. The importance of this work has increased in recent years in connection with the construction

  8. A four-channel portable solar radiometer for measuring particulate and/or aerosol opacity and concentration of NO2 and SO2 in stack plumes

    NASA Technical Reports Server (NTRS)

    Exton, R. J.; Gregory, R. W.

    1976-01-01

    Solar absorption radiometry has been investigated as a method of measuring stackplume effluents. A simple and inexpensive instrument was constructed for observing the sun at four wavelengths: 800, 600, 400, and 310 nm. Higher wavelength channels measured the effect of the particulates and NO2, and an ultraviolet channel measured the contribution of SO2 to the attenuation. Stack-plume measurements of opacity and concentration of NO2 and SO2 were in basic agreement with in-stack measurements. The major limitation on the use of the radiometer is the requirement for an accessible viewing position which allows the sun-plume-observer relationship to be attained. It was concluded that the solar radiometer offers an inexpensive method for monitoring plume effluents when the viewing position is not restricted.

  9. Effect on combined cycle efficiency of stack gas temperature constraints to avoid acid corrosion

    NASA Technical Reports Server (NTRS)

    Nainiger, J. J.

    1980-01-01

    To avoid condensation of sulfuric acid in the gas turbine exhaust when burning fuel oils contaning sulfur, the exhaust stack temperature and cold-end heat exchanger surfaces must be kept above the condensation temperature. Raising the exhaust stack temperature, however, results in lower combined cycle efficiency compared to that achievable by a combined cycle burning a sulfur-free fuel. The maximum difference in efficiency between the use of sulfur-free and fuels containing 0.8 percent sulfur is found to be less than one percentage point. The effect of using a ceramic thermal barrier coating (TBC) and a fuel containing sulfur is also evaluated. The combined-cycle efficiency gain using a TBC with a fuel containing sulfur compared to a sulfur-free fuel without TBC is 0.6 to 1.0 percentage points with air-cooled gas turbines and 1.6 to 1.8 percentage points with water-cooled gas turbines.

  10. Effect of shroud geometry on the effectiveness of a short mixing stack gas eductor model

    NASA Astrophysics Data System (ADS)

    Kavalis, A. E.

    1983-06-01

    An existing apparatus for testing models of gas eductor systems using high temperature primary flow was modified to provide improved control and performance over a wide range of gas temperature and flow rates. Secondary flow pumping, temperature and pressure data were recorded for two gas eductor system models. The first, previously tested under hot flow conditions, consists of a primary plate with four tilted-angled nozzles and a slotted, shrouded mixing stack with two diffuser rings (overall L/D = 1.5). A portable pyrometer with a surface probe was used for the second model in order to identify any hot spots at the external surface of the mixing stack, shroud and diffuser rings. The second model is shown to have almost the same mixing and pumping performance with the first one but to exhibit much lower shroud and diffuser surface temperatures.

  11. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn C. England

    2004-10-20

    In 1997, the United States Environmental Protection Agency (EPA) promulgated new National Ambient Air Quality Standards (NAAQS) for particulate matter, including for the first time particles with aerodynamic diameter smaller than 2.5 micrometers ({micro}m) referred to as PM2.5. PM2.5 in the atmosphere also contributes to reduced atmospheric visibility, which is the subject of existing rules for siting emission sources near Class 1 areas and new Regional Haze rules. There are few existing data regarding emissions and characteristics of fine aerosols from oil, gas and power generation industry combustion sources, and the information that is available is generally outdated and incomplete. Traditional stationary source air emission sampling methods tend to underestimate or overestimate the contribution of the source to ambient aerosols because they do not properly account for primary aerosol formation, which occurs after the gases leave the stack. Primary aerosol includes both filterable particles that are solid or liquid aerosols at stack temperature plus those that form as the stack gases cool through mixing and dilution processes in the plume downwind of the source. These deficiencies in the current methods can have significant impacts on regulatory decision-making. PM2.5 measurement issues were extensively reviewed by the American Petroleum Institute (API) (England et al., 1998), and it was concluded that dilution sampling techniques are more appropriate for obtaining a representative particulate matter sample from combustion systems for determining PM2.5 emission rate and chemical speciation. Dilution sampling is intended to collect aerosols including those that condense and/or react to form solid or liquid aerosols as the exhaust plume mixes and cools to near-ambient temperature immediately after the stack discharge. These techniques have been widely used in recent research studies. For example, Hildemann et al. (1994) and McDonald et al. (1998) used filtered ambient air to dilute the stack gas sample followed by 80-90 seconds residence time to allow aerosol formation and growth to stabilize prior to sample collection and analysis. More accurate and complete emissions data generated using the methods developed in this program will enable more accurate source-receptor and source apportionment analysis for PM2.5 National Ambient Air Quality Standards (NAAQS) implementation and streamline the environmental assessment of oil, gas and power production facilities. The overall goals of this program were to: (1) Develop improved dilution sampling technology and test methods for PM2.5 mass emissions and speciation measurements, and compare results obtained with dilution and traditional stationary source sampling methods. (2) Develop emission factors and speciation profiles for emissions of fine particulate matter, especially organic aerosols, for use in source-receptor and source apportionment analyses. (3) Identify and characterize PM2.5 precursor compound emissions that can be used in source-receptor and source apportionment analyses.

  12. Adjustment of the flue gas path in small combustion appliances with regard to particulate matter reduction

    NASA Astrophysics Data System (ADS)

    Sulovcová, Katarína; Janda?ka, Jozef; Nosek, Radovan

    2014-08-01

    Concentration of solid particles in ambient atmosphere is increasing in many countries nowadays. Particulate matter pollution in higher concentration has harmful impact on human and animal health. Source of particulate matter are not only industry and traffic. Small heat sources with biomass combustion, especially during winter heating season, are also significant producer of particulate matter emission. There is a huge importance to decrease quantities of solid particles which are getting into the atmosphere in every region of their production in order to decrease environmental pollution and improve air quality. The ability of flue gas emission elimination can influence future using of biomass combustion. Therefore effective and affordable solutions are searching for. The paper deals with the reduction of particulate matter in small heat source with biomass combustion by modification of geometric parameters in flue gas path.

  13. EVALUATION OF STATIONARY SOURCE PARTICULATE MEASUREMENT METHODS. VOLUME III. GAS TEMPERATURE CONTROL DURING METHOD 5 SAMPLING

    EPA Science Inventory

    A study was conducted to measure changes in gas temperature along the length of a Method 5 sampling train due to variations in stack gas temperature, sampling rate, filter box temperature and method for controlling the probe heating element. For each run condition, temperatures w...

  14. Development of a photobioreactor incorporating Chlorella sp. for removal of CO 2 in stack gas

    Microsoft Academic Search

    Yoshitomo Watanabe; Hiroshi Saiki

    1997-01-01

    We developed a new design photobioreactor incorporating Chlorella sp. for removal of CO2 in stack gas. Photosynthetic conversion of CO2 into Chlorella biomass was investigated in a photobioreactor, which we termed a cone-shaped helical tubular photobioreactor. The laboratory scale photobioreactor (0.48 m high × 0.57 m top diameter) was set up with a 0.255 m2 installation area. The photostage was

  15. Boiler stack-gas heat recovery. Final report, October 1984September 1986

    Microsoft Academic Search

    P. C. Lu; T. T. Fu; S. C. Garg; G. Nowakowski

    1987-01-01

    This report is a detailed study of various heat-recovery schemes for Navy shore facilities to use otherwise lost stack heat. The waste heat can be used alternatively to improve the boiler efficiency through feedwater and\\/or combustion-air preheating, or to lighten the boiler load through process-steam\\/water heating. The procedure for estimating the energy potential of a given flue-gas stream is explained

  16. MICROCOMPUTER PROGRAMS FOR PARTICULATE CONTROL: SECTION FAILURE; BAGHOUSE; PLUME OPACITY PREDICTION; AND IN-STACK OPACITY CALCULATOR

    EPA Science Inventory

    IBM-PC usable versions of several computer models useful in particulate control are provided. The models were originally written for the TRS-80 Model I-III series of microcomputers and have been translated to run on the IBM-PC. The documentation for the TRS-80 versions applies to...

  17. Numerical calculation of flow and stack-gas concentration fluctuation around a cubical building

    NASA Astrophysics Data System (ADS)

    Sada, K.; Sato, A.

    A numerical simulation model was developed to predict the instantaneous concentration fluctuation of a plume and applied to stack-gas diffusion around a cubical building. The flow field, including an instantaneous velocity component, was predicted using the large eddy simulation (LES) method in the developed numerical model. Then, the instantaneous concentration fluctuation was predicted using the obtained unsteady flow field. Concentration was calculated using the finite difference method, in which the LES is expanded for concentration, and the puff method, in which small volumes of the tracer gas are divided and combined according to the calculation mesh sizes. In order to avoid numerical viscous effects, a puff method and finite difference method were applied separately in the regions near and far from the stack-gas release point, respectively. Then, the flow field around a cubical building and the diffusion of stack-gas, emitted from an elevated point source at an upstream position of the building, were calculated using the model mentioned above. Numerical calculation results were compared with those obtained in wind tunnel experiments in which concentration fluctuation was measured using high-response flame ionization detectors. Although there were some discrepancies in the flow field between the calculated results and those of wind tunnel experiments, e.g., the calculated windward length of a cavity region behind the building, the calculated mean velocity and turbulent intensity showed good agreement with those of the wind tunnel experiments. Furthermore, the calculated concentration fluctuation showed good agreement with that in the wind tunnel, not only regarding the features of fluctuating concentration signals, but also statistic quantities, viz., mean concentration, fluctuation intensity and high-concentration values.

  18. Electrochemical cell stack assembly

    DOEpatents

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  19. Apparatus for removal of particulate matter from gas streams

    DOEpatents

    Smith, Peyton L. (Baton Rouge, LA); Morse, John C. (Baton Rouge, LA)

    2000-01-01

    An apparatus for the removal of particulate matter from the gaseous product stream of an entrained flow coal gasifier which apparatus includes an initial screen, an intermediate screen which is aligned with the direction of flow of the gaseous product stream and a final screen transversely disposed to the flow of gaseous product and which apparatus is capable of withstanding at least a pressure differential of about 10 psi (68.95 kPa) or greater at the temperatures of the gaseous product stream.

  20. Students' Conceptual Representations of Gas Volume in Relation to Particulate Model of Matter.

    ERIC Educational Resources Information Center

    Hwang, Bao-tyan

    Most high school chemistry curricula contain a unit on gas volume and a unit on the particulate nature of matter. The existence and persistence of adolescent preconceptions about the material nature of gases is an important factor to be considered in the teaching of principles or theories related to gases. The purpose of the study reported in this…

  1. NOVEL CONCEPTS, METHODS AND ADVANCED TECHNOLOGY IN PARTICULATE/GAS SEPARATION

    EPA Science Inventory

    This paper discusses presentations made during a symposium on novel concepts, methods, and advanced technology in particulate/gas separation. The symposium, held at the University of Notre Dame and sponsored by the National Science Foundation and the Environmental Protection Agen...

  2. Particulate flow dynamics and erosion in gas turbines

    Microsoft Academic Search

    A. Hamed; W. Tabakoff

    1987-01-01

    Results of a detailed study of the effect of particle characteristics on the particle dynamics and on the resulting pattern of particle blade impacts and the blade erosion in a two-stage axial-flow gas turbine operating with particle-laden flows are presented. The particle dynamics computations simulate particle\\/gas interactions and particle\\/blade interactions as determined from the experimental rebound characteristics The results show

  3. Probing the gas content of radio galaxies through H I absorption stacking

    NASA Astrophysics Data System (ADS)

    Geréb, K.; Morganti, R.; Oosterloo, T. A.

    2014-09-01

    Using the Westerbork Synthesis Radio Telescope, we carried out shallow H i absorption observations of a flux-selected (S1.4 GHz > 50 mJy) sample of 93 radio active galactic nuclei (AGN), which have available SDSS (Sloan Digital Sky Survey) redshifts between 0.02 < z < 0.23. Our main goal is to study the gas properties of radio sources down to S1.4 GHz flux densities not systematically explored before using, for the first time, stacking of absorption spectra of extragalactic H i. Despite the shallow observations, we obtained a direct detection rate of ~29%, comparable with deeper studies of radio galaxies. Furthermore, detections are found at every S1.4 GHz flux level, showing that H i absorption detections are not biased toward brighter sources. The stacked profiles of detections and non-detections reveal a clear dichotomy in the presence of H i, with the 27 detections showing an average peak ? = 0.02 corresponding to N(H i) ~(7.4 ± 0.2) × 1018 (Tspin/cf) cm-2, while the 66 non-detections remain undetected upon stacking with a peak optical depth upper limit ? < 0.002 corresponding to N(H i) < (2.26 ± 0.06) × 1017 (Tspin/cf) cm-2 (using a FWHM of 62 kms-1, derived from the mean width of the detections). Separating the sample into compact and extended radio sources increases the detection rate, optical depth, and FWHM for the compact sample. The dichotomy for the stacked profiles of detections and non-detections still holds between these two groups of objects. We argue that orientation effects connected to a disk-like distribution of the H i can be partly responsible for the dichotomy that we see in our sample. However, orientation effects alone cannot explain all the observational results, and some of our galaxies must be genuinely depleted of cold gas. A fraction of the compact sources in the sample are confirmed by previous studies as likely young radio sources (compact steep spectrum and gigahertz peaked spectrum sources). These show an even higher detection rate of 55%. Along with their high integrated optical depth and wider profile, this reinforces the idea that young radio AGN are embedded in a medium that is rich in atomic gas. Part of our motivation is to probe for the presence of faint H i outflows at low optical depth using stacking. However, the stacked profiles do not reveal any significant blueshifted wing. We are currently collecting more data to investigate the presence of outflows. The results presented in this paper are particularly relevant for future surveys in two ways. The lack of bias toward bright sources is encouraging for the search for H i in sources with even lower radio fluxes planned by such surveys. The results also represent a reference point when searching for H i absorption at higher redshifts.

  4. Gas and Particulate Sampling of Airborne Polycyclic Aromatic Compounds

    SciTech Connect

    Lane, D.A.; Gundel, L.A.

    1995-10-01

    The denuder surfaces of the gas and particle (GAP) sampler (developed at the Atmospheric Environment Service of Environment Canada) have been modified by coating with XAD-4 resin, using techniques developed at Lawrence Berkeley National Laboratory (LBNL) for the lower capacity integrated organic vapor/particle sampler (IOVPS). The resulting high capacity integrated organic gas and particle sampler (IOGAPS) has been operated in ambient air at 16.7 L min{sup -1} for a 24-hour period in Berkeley, California, USA. Simultaneous measurements were made at the same collection rate with a conventional sampler that used a filter followed by two sorbent beds. Gas and particle partition measurements were determined for 13 polycyclic aromatic hydrocarbons (PAH) ranging from 2-ring to 6-ring species. The IOGAPS indicated a higher particle fraction of these compounds than did the conventional sampler, suggesting that the conventional sampler suffered from 'blow-off' losses from the particles collected on the filter.

  5. Assessment of the Losses Due to Self Absorption by Mass Loading on Radioactive Particulate Air Stack Sample Filters

    SciTech Connect

    Smith, Brian M.; Barnett, J. M.; Ballinger, Marcel Y.

    2011-01-18

    This report discusses the effect of mass loading of a membrane filter on the self absorption of radioactive particles. A relationship between mass loading and percent loss of activity is presented. Sample filters were collected from Pacific Northwest National Laboratory (PNNL) facilities in order to analyze the current self absorption correction factor of 0.85 that is being used for both alpha and beta particles. Over an eighteen month period from February 2009 to July 2010, 116 samples were collected and analyzed from eight different building stacks in an effort coordinated by the Effluent Management group. Eleven unused filters were also randomly chosen to be analyzed in order to determine background radiation. All of these samples were collected and analyzed in order to evaluate the current correction factor being used.

  6. Numerical Simulation of CO and NO Emissions during Converter Off-Gas Combustion in the Cooling Stack

    Microsoft Academic Search

    Sen Li; Xiaolin Wei

    2012-01-01

    Oxygen converter steelmaking produces a large amount of high temperature off-gas. During pre- and post-combustion of converter off-gas in the cooling stack, CO concentration at outlet is always over emission standard, and NO emission is still paid little attention. In the paper, CO and NO emissions are investigated during converter off-gas combustion by CFD. The simulation results indicate that CO

  7. Trace gas and particulate emissions from biomass burning in temperate ecosystems

    NASA Technical Reports Server (NTRS)

    Cofer, Wesley R., III; Levine, Joel S.; Winstead, Edward L.; Stocks, Brian J.

    1991-01-01

    Emissions measured from fires in graminoid wetlands, Mediterranean chaparrals, and boreal forests, suggest that such ecosystemic parameters as fuel size influence combustion emissions in ways that are broadly predictable. The degree of predictability is most noticeable when wetland fire-related results are compared with boreal forest emissions; the inorganic fraction of the particulate emissions is close in composition irrespective of the ecosystem. It is found that both aerosol and trace gas emissions are influenced by the phase of combustion.

  8. Waste Gas And Particulate Control Measures For Laser Cutters In The Automotive Cloth Industry

    NASA Astrophysics Data System (ADS)

    Ball, R. D.; Kulik, B. F.; Stoncel, R. J.; Tan, S. L.

    1986-11-01

    Demands for greater flexibility and accuracy in the manufacture of automobile trim parts has made single-ply laser cutting an attractive proposition. Lasers are able to cut a large variety of cloth types, from vinyls to velours. Unlike mechanically cut parts, which in the case of velours produce rough edges and dust problems, laster cutting of parts produces smooth edges, fumes and fine particulate. A detailed study of the nature of the laser effluent from a cross section of typical synthetic cloth found in an automotive trim plant was undertaken. Most samples were cut by a fast axial flow, 500 Watt, continuous wave CO2 laser. A 254 mm (10-inch) focussing optics package was used. The width of the kerf varied with the material, and values were determined at between 0.2 and 0.7 mm. Particle size distribution analysis and rates of particulate emission for each cloth were determined. Gases were collected in gas sample bags and analyzed using Fourier transform infrared analysis. Low boiling point organics were collected on activated charcoal tubes, identified on a gas chromatograph mass spectrometer, and quantified on a gas chromatograph. Inorganic contaminants were collected on filter paper and analysed on an inductively coupled plasma atomic emission spectrometer. A number of different effluent control systems were evaluated. Due to the very fine and sticky nature of the particulate, filters capable of removing particulate sizes in the 10 ?m or lower range, tend to clog rapidly. Laboratory scale models of wet scrubbers, and electrostatic precipitators were built and tested. The most effective dust and effluent gas control was given by a wet electrostatic precipitator. This system, in conjunction with a scrubber, should maintain emission levels within environmental standards.

  9. Mobile Gas and Particulate Emission Studies of the New York City Transit Bus Fleet

    Microsoft Academic Search

    J. T. Jayne; M. Canagaratna; S. Herndon; J. Shorter; M. Zahniser; Q. Shi; C. Kolb; D. Worsnop; J. Jimenez; F. Drewnick; K. Demerjian; T. Lanni

    2001-01-01

    Emissions from both diesel and gasoline powered motor vehicles are a significant source of particulate (PM2.5) and trace gas pollution, especially in urban environments. Emission characterizations of motor vehicles can be performed using a dynamometer but these studies make fleet characterization impractical. Few studies have been performed which characterize emissions from in-use vehicles using a mobile sampling platform. This work

  10. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...gas meters or flow instrumentation to determine flow through the particulate filters, methanol impingers...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, a laminar flow element or an NBS traceable flow...

  11. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...gas meters or flow instrumentation to determine flow through the particulate filters, methanol impingers...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, a laminar flow element or an NBS traceable flow...

  12. Analysis of benzo(a)pyrene in airborne particulates by gas chromatography

    NASA Technical Reports Server (NTRS)

    Luedecke, E.

    1976-01-01

    A routine method was developed to measure benzo(a)pyrene in airborne particulates. Samples were collected on a filter and the organic portion was extracted with cyclohexane. The polynuclear hydrocarbon (PNHC) fraction was separated from the aliphatics by column chromatography. An internal standard was added to the extract and a portion of it was injected into a gas chromatograph. Although the gas chromatographic method has often been reported in the literature, satisfactory separation of benzo(a)pyrene and benzo(e)pyrene has not been achieved. With the introduction of a nematic liquid crystal as the stationary phase good separation is now possible.

  13. The composition of lignin in estuarine suspended particulates and the distribution of particulate lignin in estuaries as determined by capillary gas chromatography of cupric oxide oxidation products

    NASA Astrophysics Data System (ADS)

    Reeves, A. D.; Preston, M. R.

    1989-12-01

    The contribution of lignin to the estuarine suspended particulate fraction is described in terms of its distribution over a spring tide and a neap tide in the Tamar Estuary, Southwest England and the Mersey Estuary, Northwest England. Suspended particulate samples are treated with CuO?NaOH at 170°C to yield simple, lignin-derived phenolic compounds, which are separated, derived and quantified by capillary gas chromatography with flame ionization detection (GC-FID). Estuarine distributions of particulate lignin are described and the sources and compositional changes of the lignin identified. Comparison of the lignin concentrations in the suspended material with those in the underlying sediment reveals that lignin is preferentially enriched in the suspended material.

  14. The Lockman Hole project: gas and galaxy properties from a stacking experiment

    NASA Astrophysics Data System (ADS)

    Geréb, K.; Morganti, R.; Oosterloo, T. A.; Guglielmino, G.; Prandoni, I.

    2013-10-01

    We perform an H I stacking analysis to study the relation between H I content and optical/radio/IR properties of galaxies located in the Lockman Hole area. In the redshift range covered by the observations (up to z = 0.09), we use the SDSS to separate galaxies with different optical characteristics, and we exploit the deep L-band radio continuum image (with noise 11 ?Jy beam-1) to identify galaxies with radio continuum emission. Infrared properties are extracted from the Spitzer catalog. We detect H I in blue galaxies, but H I is also detected in the group of red galaxies - albeit with smaller amounts than for the blue sample. We identify a group of optically inactive galaxies with early-type morphology that does not reveal any H I and ionized gas. These inactive galaxies likely represent the genuine red and dead galaxies depleted of all gas. Unlike inactive galaxies, H I is detected in red LINER-like objects. Galaxies with radio continuum counterparts mostly belong to the sub-mJy population, whose objects are thought to be a mixture of star-forming galaxies and low-power AGNs. After using several AGN diagnostics, we conclude that the radio emission in the majority of our sub-mJy radio sources stems from star formation. LINERs appear to separate into two groups based on IR properties and H I content. LINERs with a 24 ?m detection show relatively large amounts of H I and are also often detected in radio continuum as a result of ongoing star formation. The LINER galaxies which are not detected at 24 ?m are more like the optically inactive galaxies by being depleted of H I gas and having no sign of star formation. Radio LINERs in the latter group are the best candidates for hosting low-luminosity radio AGN.

  15. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn England; Oliver Chang; Stephanie Wien

    2002-02-14

    This report provides results from the second year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operation. Detailed emission rate and chemical speciation tests results for a gas turbine, a process heater, and a commercial oil/gas fired boiler are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods. A series of pilot tests were conducted to identify the constraints to reduce the size of current research dilution sampler for future stack emission tests. Based on the test results, a bench prototype compact dilution sampler developed and characterized in GE EER in August 2002.

  16. Mobile Gas and Particulate Emission Studies of the New York City Transit Bus Fleet

    NASA Astrophysics Data System (ADS)

    Jayne, J. T.; Canagaratna, M.; Herndon, S.; Shorter, J.; Zahniser, M.; Shi, Q.; Kolb, C.; Worsnop, D.; Jimenez, J.; Drewnick, F.; Demerjian, K.; Lanni, T.

    2001-12-01

    Emissions from both diesel and gasoline powered motor vehicles are a significant source of particulate (PM2.5) and trace gas pollution, especially in urban environments. Emission characterizations of motor vehicles can be performed using a dynamometer but these studies make fleet characterization impractical. Few studies have been performed which characterize emissions from in-use vehicles using a mobile sampling platform. This work describes application of new technology instrumentation for rapid (1-5 second) and real-time characterization of both gas and particulate emissions from in-use vehicles and is part of the PM2.5 Technology Assessment and Characterization Study in New York (PMTACS-NY). An aerosol mass spectrometer (AMS) and a tunable infrared laser differential absorption spectrometer (TILDAS) system were deployed on the Aerodyne Research mobile laboratory designed to "chase" target vehicles in and around the New York City area and measure their emissions under actual driving conditions. The AMS provides particle size and composition information for volatile and semi-volatile matter while the TILDAS system was configured to measure NO, NO2, CO, CH4, SO2 and formaldehyde. In addition to a GPS, an ELPI and a condensation particle counter, the mobile laboratory was also equipped with a CO2 monitor to allow emission ratios to be computed for the targeted vehicles. Emission ratios for both particulate and trace gases are reported for a representative fraction of the NYC Metropolitan Transit Authority (MTA) bus fleet in an effort to characterize new emission control technologies currently implemented by the NYC MTA.

  17. Identification of indicator congeners and evaluation of emission pattern of polychlorinated naphthalenes in industrial stack gas emissions by statistical analyses.

    PubMed

    Liu, Guorui; Cai, Zongwei; Zheng, Minghui; Jiang, Xiaoxu; Nie, Zhiqiang; Wang, Mei

    2015-01-01

    Identifying marker congeners of unintentionally produced polychlorinated naphthalenes (PCNs) from industrial thermal sources might be useful for predicting total PCN (?2-8PCN) emissions by the determination of only indicator congeners. In this study, potential indicator congeners were identified based on the PCN data in 122 stack gas samples from over 60 plants involved in more than ten industrial thermal sources reported in our previous case studies. Linear regression analyses identified that the concentrations of CN27/30, CN52/60, and CN66/67 correlated significantly with ?2-8PCN (R(2)=0.77, 0.80, and 0.58, respectively; n=122, p<0.05), which might be good candidates for indicator congeners. Equations describing relationships between indicators and ?2-8PCN were established. The linear regression analyses involving 122 samples showed that the relationships between the indicator congeners and ?2-8PCN were not significantly affected by factors such as industry types, raw materials used, or operating conditions. Hierarchical cluster analysis and similarity calculations for the 122 stack gas samples were adopted to group those samples and evaluating their similarity and difference based on the PCN homolog distributions from different industrial thermal sources. Generally, the fractions of less chlorinated homologs comprised of di-, tri-, and tetra-homologs were much higher than that of more chlorinated homologs for up to 111 stack gas samples contained in group 1 and 2, which indicating the dominance of lower chlorinated homologs in stack gas from industrial thermal sources. PMID:25218874

  18. Testing of a shrouded, short mixing stack gas eductor model using high temperature primary flow. Master's thesis

    SciTech Connect

    Eick, I.J.

    1982-10-01

    An existing apparatus for testing models of gas eductor systems using high temperature primary flow was redesigned and modified to provide improved control and performance over a wide range of gas temperatures and flow rates. Pumping coefficient, temperature, and pressure data were recorded for two gas eductor system models. The first, previously tested under hot flow conditions, consisted of a primary plate with four straight nozzles and a slotted, shrouded mixing stack with two ring diffuser (L/D=2.5). The second was geometrically similar to a model previously tested in cold flow. This model employed a primary plate with four tilted-angled nozzles and a slotted, shrouded mixing stack with two ring diffuser (L/D=1.5). Thermal imagery was used to generalize the data obtained by direct temperature measurement. The validity of cold flow model testing is confirmed. The short stack with tilted-angled primary nozzles is shown to have superior mixing and pumping performance, but to exhibit significantly higher shroud and diffuser surface temperatures.

  19. ALFALFA HI Data Stacking III. Comparison of environmental trends in HI gas mass fraction and specific star formation rate

    E-print Network

    Fabello, Silvia; Catinella, Barbara; Li, Cheng; Giovanelli, Riccardo; Haynes, Martha P

    2012-01-01

    It is well known that both the star formation rate and the cold gas content of a galaxy depend on the local density out to distances of a few Megaparsecs. In this paper, we compare the environmental density dependence of the atomic gas mass fractions of nearby galaxies with the density dependence of their central and global specific star formation rates. We stack HI line spectra extracted from the Arecibo Legacy Fast ALFA survey centered on galaxies with UV imaging from GALEX and optical imaging/spectroscopy from SDSS. We use these stacked spectra to evaluate the mean atomic gas mass fraction of galaxies in bins of stellar mass and local density. For galaxies with stellar masses less than 10^10.5 M_sun, the decline in mean atomic gas mass fraction with density is stronger than the decline in mean global and central specific star formation rate. The same conclusion does not hold for more massive galaxies. We interpret our results as evidence for ram-pressure stripping of atomic gas from the outer disks of low ...

  20. Separation of particulate from flue gas of fossil fuel combustion and gasification

    DOEpatents

    Yang, W.C.; Newby, R.A.; Lippert, T.E.

    1997-08-05

    The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The fly ash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured fly ash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled. 11 figs.

  1. Separation of particulate from flue gas of fossil fuel combustion and gasification

    DOEpatents

    Yang, Wen-Ching (Murrysville, PA); Newby, Richard A. (Pittsburgh, PA); Lippert, Thomas E. (Murrysville, PA)

    1997-01-01

    The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The flyash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured flyash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled.

  2. Evaluation of a Combined Cyclone and Gas Filtration System for Particulate Removal in the Gasification Process

    SciTech Connect

    Rizzo, Jeffrey J. [Phillips66 Company, West Terre Haute, IN (United States)

    2010-04-30

    The Wabash gasification facility, owned and operated by sgSolutions LLC, is one of the largest single train solid fuel gasification facilities in the world capable of transforming 2,000 tons per day of petroleum coke or 2,600 tons per day of bituminous coal into synthetic gas for electrical power generation. The Wabash plant utilizes Phillips66 proprietary E-Gas (TM) Gasification Process to convert solid fuels such as petroleum coke or coal into synthetic gas that is fed to a combined cycle combustion turbine power generation facility. During plant startup in 1995, reliability issues were realized in the gas filtration portion of the gasification process. To address these issues, a slipstream test unit was constructed at the Wabash facility to test various filter designs, materials and process conditions for potential reliability improvement. The char filtration slipstream unit provided a way of testing new materials, maintenance procedures, and process changes without the risk of stopping commercial production in the facility. It also greatly reduced maintenance expenditures associated with full scale testing in the commercial plant. This char filtration slipstream unit was installed with assistance from the United States Department of Energy (built under DOE Contract No. DE-FC26-97FT34158) and began initial testing in November of 1997. It has proven to be extremely beneficial in the advancement of the E-Gas (TM) char removal technology by accurately predicting filter behavior and potential failure mechanisms that would occur in the commercial process. After completing four (4) years of testing various filter types and configurations on numerous gasification feed stocks, a decision was made to investigate the economic and reliability effects of using a particulate removal gas cyclone upstream of the current gas filtration unit. A paper study had indicated that there was a real potential to lower both installed capital and operating costs by implementing a char cyclonefiltration hybrid unit in the E-Gas (TM) gasification process. These reductions would help to keep the E-Gas (TM) technology competitive among other coal-fired power generation technologies. The Wabash combined cyclone and gas filtration slipstream test program was developed to provide design information, equipment specification and process control parameters of a hybrid cyclone and candle filter particulate removal system in the E-Gas (TM) gasification process that would provide the optimum performance and reliability for future commercial use. The test program objectives were as follows: 1. Evaluate the use of various cyclone materials of construction; 2. Establish the optimal cyclone efficiency that provides stable long term gas filter operation; 3. Determine the particle size distribution of the char separated by both the cyclone and candle filters. This will provide insight into cyclone efficiency and potential future plant design; 4. Determine the optimum filter media size requirements for the cyclone-filtration hybrid unit; 5. Determine the appropriate char transfer rates for both the cyclone and filtration portions of the hybrid unit; 6. Develop operating procedures for the cyclone-filtration hybrid unit; and, 7. Compare the installed capital cost of a scaled-up commercial cyclone-filtration hybrid unit to the current gas filtration design without a cyclone unit, such as currently exists at the Wabash facility.

  3. Characterization of particulate matter emissions from a current technology natural gas engine.

    PubMed

    Thiruvengadam, Arvind; Besch, Marc C; Yoon, Seungju; Collins, John; Kappanna, Hemanth; Carder, Daniel K; Ayala, Alberto; Herner, Jorn; Gautam, Mridul

    2014-07-15

    Experiments were conducted to characterize the particulate matter (PM)-size distribution, number concentration, and chemical composition emitted from transit buses powered by a USEPA 2010 compliant, stoichiometric heavy-duty natural gas engine equipped with a three-way catalyst (TWC). Results of the particle-size distribution showed a predominant nucleation mode centered close to 10 nm. PM mass in the size range of 6.04 to 25.5 nm correlated strongly with mass of lubrication-oil-derived elemental species detected in the gravimetric PM sample. Results from oil analysis indicated an elemental composition that was similar to that detected in the PM samples. The source of elemental species in the oil sample can be attributed to additives and engine wear. Chemical speciation of particulate matter (PM) showed that lubrication-oil-based additives and wear metals were a major fraction of the PM mass emitted from the buses. The results of the study indicate the possible existence of nanoparticles below 25 nm formed as a result of lubrication oil passage through the combustion chamber. Furthermore, the results of oxidative stress (OS) analysis on the PM samples indicated strong correlations with both the PM mass calculated in the nanoparticle-size bin and the mass of elemental species that can be linked to lubrication oil as the source. PMID:24960475

  4. Black carbon particulate matter emission factors for buoyancy-driven associated gas flares.

    PubMed

    McEwen, James D N; Johnson, Matthew R

    2012-03-01

    Flaring is a technique used extensively in the oil and gas industry to burn unwanted flammable gases. Oxidation of the gas can preclude emissions of methane (a potent greenhouse gas); however, flaring creates other pollutant emissions such as particulate matter (PM) in the form of soot or black carbon (BC). Currently available PM emissionfactors for flares were reviewed and found to be questionably accurate, or based on measurements not directly relevant to open-atmosphere flares. In addition, most previous studies of soot emissions from turbulent diffusion flames considered alkene or alkyne based gaseous fuels, and few considered mixed fuels in detail and/or lower sooting propensity fuels such as methane, which is the predominant constituent of gas flared in the upstream oil and gas industry. Quantitative emission measurements were performed on laboratory-scale flares for a range of burner diameters, exit velocities, and fuel compositions. Drawing from established standards, a sampling protocol was developed that employed both gravimetric analysis of filter samples and real-time measurements of soot volume fraction using a laser-induced incandescence (LII) system. For the full range of conditions tested (burner inner diameter [ID] of 12.7-76.2 mm, exit velocity 0.1-2.2 m/sec, 4- and 6-component methane-based fuel mixtures representative of associated gas in the upstream oil industry), measured soot emission factors were less than 0.84 kg soot/10(3) m3 fuel. A simple empirical relationship is presented to estimate the PM emission factor as a function of the fuel heating value for a range of conditions, which, although still limited, is an improvement over currently available emission factors. PMID:22482289

  5. Concept Learning versus Problem Solving: Evaluating a Threat to the Validity of a Particulate Gas Law Question

    ERIC Educational Resources Information Center

    Sanger, Michael J.; Vaughn, C. Kevin; Binkley, David A.

    2013-01-01

    Three different samples of students were asked to answer five multiple-choice questions concerning the properties of a sample of helium gas (particle speed, state of matter, sample volume, sample pressure, and particle distribution), including a particulate question first used by Nurrenbern and Pickering (particle distribution). In the first…

  6. Gas chromatographic analysis of organic marker compounds in fine particulate matter using solid-phase microextraction.

    PubMed

    Lin, Lin; Lee, Milton L; Eatough, Delbert J

    2007-01-01

    A gas chromatographic method that uses solid-phase microextraction for analysis of organic marker compounds in fine particulate matter (PM2.5) is reported. The target marker compounds were selected for specificity toward emission from wood smoke, diesel or gasoline combustion, or meat cooking. Temperature-programmed volatilization analysis was used to characterize the thermal stabilities and volatile properties of the compounds of interest. The compounds were thermally evaporated from a quartz filter, sorbed to a solid phase microextraction (SPME) fiber, and thermally desorbed at 280 degrees C in a gas chromatograph injection port connected via a DB 1701 capillary separating column. Various experimental parameters (fiber type, time, and temperature of sorption) were optimized. It was found that high extraction yield could be achieved using a polyacrylate fiber for polar substances, such as levoglucosan, and a 7-microm polydimethylsiloxane (PDMS)-coated fiber for nonpolar compounds, such as hopanes and polyaromatic hydrocarbon. A compromise was made by selecting a carboxen/PDMS fiber, which can simultaneously extract all of the analytes of interest with moderate-to-high efficiency at 180 degrees C within a 30-min accumulation period. The optimized method was applied to the determination of levoglucosan in pine wood combustion emissions. The simplicity, rapidity, and selectivity of sample collection with a polymer-coated SPME coupled to capillary gas chromatography (GC) made this method potentially useful for atmospheric chemistry studies. PMID:17269230

  7. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, Claude R. (Paducah, KY); Ernstberger, Harold G. (Paducah, KY)

    1988-01-01

    A method for monitoring the stack gases of a purge cascade of a gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases.

  8. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, C.R.; Ernstberger, E.G.

    1985-07-03

    A method for monitoring the stack gases of a purge cascade of gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases. 1 fig.

  9. Comparison of different gas-phase mechanisms and aerosol modules for simulating particulate matter formation.

    PubMed

    Kim, Youngseob; Couvidat, Florian; Sartelet, Karine; Seigneur, Christian

    2011-11-01

    The effects of two gas-phase chemical kinetic mechanisms, Regional Atmospheric Chemistry Mechanism version 2 (RACM2) and Carbon-Bond 05 (CB05), and two secondary organic aerosol (SOA) modules, the Secondary Organic Aerosoi Model (SORGAM) and AER/EPRI/Caltech model (AEC), on fine (aerodynamic diameter < or =2.5 microm) particulate matter (PM2.5) formation is studied. The major sources of uncertainty in the chemistry of SOA formation are investigated. The use of all major SOA precursors and the treatment of SOA oligomerization are found to be the most important factors for SOA formation, leading to 66% and 60% more SOA, respectively. The explicit representation of high-NO, and low-NOx gas-phase chemical regimes is also important with increases in SOA of 30-120% depending on the approach used to implement the distinct SOA yields within the gas-phase chemical kinetic mechanism; further work is needed to develop gas-phase mechanisms that are fully compatible with SOA formation algorithms. The treatment of isoprene SOA as hydrophobic or hydrophilic leads to a significant difference, with more SOA being formed in the latter case. The activity coefficients may also be a major source of uncertainty, as they may differ significantly between atmospheric particles, which contain a myriad of SOA, primary organic aerosol (POA), and inorganic aerosol species, and particles formed in a smog chamber from a single precursor under dry conditions. Significant interactions exist between the uncertainties of the gas-phase chemistry and those of the SOA module. PMID:22168105

  10. On-line analysis of the size distribution of fine and ultrafine aerosol particles in flue and stack gas of a municipal waste incineration plant: effects of dynamic process control measures and emission reduction devices.

    PubMed

    Maguhn, Jürgen; Karg, Erwin; Kettrup, Antonius; Zimmermann, Ralf

    2003-10-15

    The size distribution of particles in the waste gas of a municipal waste incineration plant (23 MW) was measured on-line at two sampling points in the flue-gas duct (700 and 300 degrees C) as well as in the stack gas (80 degrees C). The measurements were performed during both stable combustion conditions and transient operating conditions. The particle measurements were carried out by a mobile system consisting of a home-designed sampling system with dilution device and a scanning mobility particle sizer (SMPS) for the particle size range 17-600 nm as well as an aerodynamic particle sizer (APS) for the size range 500 nm-30 microm. The APS and SMPS data were combined using a special method and a home written software tool. The maximum of the particle-size distribution in the flue gas of the incinerator shifts from about 90 nm at the 700 degrees C sampling point to about 140 nm at the 300 degrees C point, showing the particle growth by coagulation processes and condensation of inorganic and organic gaseous species with decreasing temperature. This finding is consistent with the measured concentration profiles of gaseous organic chemical species in the flue gas. While at flue-gas temperatures of 600-800 degrees C a rich pattern of polycyclic aromatic hydrocarbon species (PAH) is observable, the PAH concentrations are considerably reduced further downstream of the flue-gas channel, where the temperature drops below 500 degrees C. Condensation and reactive bonding of gaseous chemicals onto particulate matter is, among other reasons, responsible for the depletion of gas-phase species. Process control measures, such as firing the backup burners or cleaning of the grate with pressurized air, can cause dynamic changes of the particle-size distribution. Furthermore the flue-gas cleaning measures have great impact onto both the particle concentration and the size distribution. For this reason the impact of one particular emission reduction device, the wet electrostatic dust precipitator (wet-ESP), is evaluated. The wet-ESP reduces considerably the particle concentration over the whole size range. Behind the flue-gas processing units a broad maximum in the particle-size distribution occurs at about 70 nm, but no pronounced particle-size distribution could be observed. The particle concentration level atthis maximum is about 3 magnitudes lower than in the raw flue gas. However, intermittent periods lasting for several minutes of high emissions of ultrafine particles with d < 40 nm were observed. These particles are most likely formed by nucleation processes behind the wet-ESP from gas-phase constituents of the stack gas. PMID:14594389

  11. 23. Brick coke quencher, brick stack, metal stack to right, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Brick coke quencher, brick stack, metal stack to right, coke gas pipe to left; in background, BOF building, limestone piles, Levy's Slag Dump. Looking north/northwest - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

  12. Post-test analysis of 20kW molten carbonate fuel cell stack operated on coal gas. Final report, August 1993--February 1996

    SciTech Connect

    NONE

    1996-05-01

    A 20kW carbonate fuel cell stack was operated with coal gas for the first time in the world. The stack was tested for a total of 4,000 hours, of which 3,900 hours of testing was conducted at the Louisiana Gasification Technology Incorporated, Plaquemine, Louisiana outdoor site. The operation was on either natural gas or coal gas and switched several times without any effects, demonstrating duel fuel capabilities. This test was conducted with 9142 kJ/m{sup 3} (245 Btu/cft) coal gas provided by a slipstream from Destec`s entrained flow, slagging, slurry-fed gasifier equipped with a cold gas cleanup subsystem. The stack generated up to 21 kW with this coal gas. Following completion of this test, the stack was brought to Energy Research Corporation (ERC) and a detailed post-test analysis was conducted to identify any effects of coal gas on cell components. This investigation has shown that the direct fuel cell (DFC) can be operated with properly cleaned and humidified coal-as, providing stable performance. The basic C direct fuel cell component materials are stable and display normal stability in presence of the coal gas. No effects of the coal-borne contaminants are apparent. Further cell testing at ERC 1 17, confirmed these findings.

  13. Sampling of power plant stacks for air toxic emissions: Topical report for Phases 1 and 2

    SciTech Connect

    NONE

    1995-02-21

    Under contract with the US Department of Energy (DE-AC22-92PCO0367), Pittsburgh Energy Technology Center, Radian Corporation has conducted a test program to collect and analyze size-fractionated stack gas particulate samples for selected inorganic hazardous air pollutants (HAPS). Specific goals of the program are (1) the collection of one-gram quantities of size-fractionated stack gas particulate matter for bulk (total) and surface chemical charactization, and (2) the determination of the relationship between particle size, bulk and surface (leachable) composition, and unit load. The information obtained from this program identifies the effects of unit load, particle size, and wet FGD system operation on the relative toxicological effects of exposure to particulate emissions.

  14. [Determination of mono- to tri-chlorinated dibenzo-p-dioxins and dibenzofurans in stack gas using isotope dilution high resolution gas chromatography-high resolution mass spectrometry].

    PubMed

    Tang, Chen; Liu, Qipeng; Tian, Zhenyu; Xie, Huiting; Wang, Mengjing; Liu, Wenbin

    2014-09-01

    A method for the determination of mono- to tri-chlorinated dibenzo-p-dioxins and dibenzofurans (mono- to tri-CDD/Fs) in stack gas using isotope dilution high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) was developed. The sam- ples were extracted by Soxhlet extraction, and then the extracts were concentrated and purified using a multilayer silica gel column and a basic alumina column. The analytes were separated by HRGC on a DB-5MS column (30 m x 0.25 mm x 0.25 ?m) and determined by HRMS. The identi- fication of mono- to tri-CDD/Fs was based on the retention times of 13C-labelled standard and the abundance ratios of the two exacted mass-to-charge ratios. The quantitative analysis was performed using the ratios of the integrated areas of the 13C-labelled standards. This method had the recoveries ranging from 66.6% to 112.5% and the relative standard deviations (RSD) ranging from 19.9% to 40.5% (n = 5). The limits of detection (LODs) of this method for the mono- to tri-CDD/Fs were ranging from 0.027 to 0.485 ?g/L. Three stack gas samples from waste incinerators were measured using this method, with the recoveries ranging from 85.7% to 137.0% and the concentrations ranging from 11.4 to 9,183 pg/Nm3. The results indicated that the method can be applied to the precise determination of mono- to tri-CDD/Fs at trace level in stack gas. PMID:25752087

  15. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...instrumentation calibration; particulate, methanol, and formaldehyde measurement...instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

  16. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...instrumentation calibration; particulate, methanol and formaldehyde measurement. 86...instrumentation calibration; particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

  17. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...instrumentation calibration; particulate, methanol, and formaldehyde measurement...instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

  18. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...instrumentation calibration; particulate, methanol and formaldehyde measurement. 86...instrumentation calibration; particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

  19. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...instrumentation calibration; particulate, methanol and formaldehyde measurement. 86...instrumentation calibration; particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

  20. Gas/solid particulate phthalic esters (PAEs) in Masson pine (Pinus massoniana L.) needles and rhizosphere surface soils.

    PubMed

    Wang, Wen-xin; Fan, Chinbay Q

    2014-07-15

    Phthalic acid esters (PAEs) are used in many branches of industry and are produced in huge amounts throughout the world. An investigation on particulate- and gas-phase distribution of PAEs has been conducted between January 2011 and December 2012 in Nanjing (China). Masson pine (Pinus massoniana L.) needles and rhizosphere surface soils were sampled from urban to suburban/remote sites, to investigate the pine needle/soil distribution of PAEs. The results showed that the average total PAE concentration (gas+particle) was 97.0ngm(-3). The six PAE congeners considered predominantly existed in the gas phase and the average contribution of gas phase to total PAEs ranged from 75.0% to 89.1%. The PAE concentrations in rhizosphere soils and pine needles were positively correlated with their particulate- and gas-phase concentrations, respectively, which suggested that surface soils accumulated PAEs mainly through gravity deposition of particles and pine needle stomata absorbed PAEs mainly from the gas phase. The gas/particle partitioning (KP) and soil-pine needle ratio (Rs/n) were determined. Experimentally determined KP values correlated well with the subcooled liquid vapor pressures (PL). A set of interesting relationships of logRs/n-logKP-logPL was employed to explain the experimental findings of PAEs deposition to surface soils and to needles. This data set offered a unique perspective into the influence that Rs/n played in KP and correlated with PL. PMID:24887117

  1. Effect of shroud geometry on the effectiveness of a short mixing stack gas eductor model

    Microsoft Academic Search

    A. E. Kavalis

    1983-01-01

    An existing apparatus for testing models of gas eductor systems using high temperature primary flow was modified to provide improved control and performance over a wide range of gas temperature and flow rates. Secondary flow pumping, temperature and pressure data were recorded for two gas eductor system models. The first, previously tested under hot flow conditions, consists of a primary

  2. Including impacts of particulate emissions on marine ecosystems in life cycle assessment: the case of offshore oil and gas production.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Rye, Henrik; Hertwich, Edgar G

    2011-10-01

    Life cycle assessment is increasingly used to assess the environmental performance of fossil energy systems. Two of the dominant emissions of offshore oil and gas production to the marine environment are the discharge of produced water and drilling waste. Although environmental impacts of produced water are predominantly due to chemical stressors, a major concern regarding drilling waste discharge is the potential physical impact due to particles. At present, impact indicators for particulate emissions are not yet available in life cycle assessment. Here, we develop characterization factors for 2 distinct impacts of particulate emissions: an increased turbidity zone in the water column and physical burial of benthic communities. The characterization factor for turbidity is developed analogous to characterization factors for toxic impacts, and ranges from 1.4 PAF (potentially affected fraction) · m(3) /d/kg(p) (kilogram particulate) to 7.0 x 10³ [corrected] for drilling mud particles discharged from the rig. The characterization factor for burial describes the volume of sediment that is impacted by particle deposition on the seafloor and equals 2.0 × 10(-1) PAF · m(3) /d/kg(p) for cutting particles. This characterization factor is quantified on the basis of initial deposition layer characteristics, such as height and surface area, the initial benthic response, and the recovery rate. We assessed the relevance of including particulate emissions in an impact assessment of offshore oil and gas production. Accordingly, the total impact on the water column and on the sediment was quantified based on emission data of produced water and drilling waste for all oil and gas fields on the Norwegian continental shelf in 2008. Our results show that cutting particles contribute substantially to the total impact of offshore oil and gas production on marine sediments, with a relative contribution of 55% and 31% on the regional and global scale, respectively. In contrast, the contribution of particulate emissions to the total impact on the marine water column is of minor importance. We conclude that particles are an important stressor in marine ecosystems, particularly for marine sediment, and particulate emissions should therefore be included in a (life cycle) impact assessment of offshore oil and gas production. PMID:21735543

  3. STUDY ON THE FEASIBILITY AND DESIGN OF AUTOMATIC PARTICULATE SIZE DISTRIBUTION ANALYZER FOR SOURCE EMISSIONS

    EPA Science Inventory

    The objective of this program was to evolve a method for the automatic determination of the size distribution of particulates within stack gas effluent streams. This device was designed to cover the typical mass concentration range encountered upstream as well as downstream of em...

  4. Gas dispersion concentration of trace inorganic contaminants from fuel gas and analysis using head-column field-amplified sample stacking capillary electrophoresis.

    PubMed

    Yang, Jianmin; Li, Hai-Fang; Li, Meilan; Lin, Jin-Ming

    2012-08-21

    The presence of inorganic elements in fuel gas generally accelerates the corrosion and depletion of materials used in the fuel gas industry, and even leads to serious accidents. For identification of existing trace inorganic contaminants in fuel gas in a portable way, a highly efficient gas-liquid sampling collection system based on gas dispersion concentration is introduced in this work. Using the constructed dual path gas-liquid collection setup, inorganic cations and anions were simultaneously collected from real liquefied petroleum gas (LPG) and analyzed by capillary electrophoresis (CE) with indirect UV absorbance detection. The head-column field-amplified sample stacking technique was applied to improve the detection limits to 2-25 ng mL(-1). The developed collection and analytical methods have successfully determined existing inorganic contaminants in a real LPG sample in the range of 4.59-138.69 ?g m(-3). The recoveries of cations and anions with spiked LPG samples were between 83.98 and 105.63%, and the relative standard deviations (RSDs) were less than 7.19%. PMID:22733372

  5. Pd-110/108 Ratios and Trace Element Changes in Particulate Palladium Exposed to Deuterium Gas

    NASA Astrophysics Data System (ADS)

    Passell, Thomas O.

    2005-12-01

    Changes in Pd-110/108 ratios as well as the concentration of silver, gold, zinc, cobalt, iridium and lithium-7/6 ratios have been measured using neutron activation analysis (NAA) and time of flight secondary ion mass spectrometry (TOF-SIMS) on a set of four samples of particulate palladium exposed to high-pressure deuterium gas in the hollow core of Arata-Zhang cathodes. Three samples were from cathodes producing excess heat (tens of megajoules) over a period of several-months electrolysis, while the fourth was virgin powder from the same batch as that of the active samples. If a nuclear process is the source of these changes, then multi-isotope elements such as silver, zinc, and iridium should show significant deviations in their isotopic ratios from the natural terrestrial values. Surface trace lithium did indeed show such differences from that of the virgin material. The Ag-109/107 ratio is currently under study by accelerator mass spectroscopy (AMS) for the one sample showing the greatest difference in Ag-109 content from that of the virgin material. Since these variations may have explanations unrelated to nuclear reactions, these results are not yet definitive. The 8% increase in the Pd-110/108 ratio for one of the four samples relative to the virgin material is one of the most difficult for which to find a conventional explanation.

  6. Feasibility of an alpha particle gas densimeter for stack sampling applications

    E-print Network

    Johnson, Randall Mark

    1983-01-01

    , for conceivable ranges of flue gas composition, the maximum error in density due to the uncertainty in gas composition is less than 2%. ACKNOWLEDGEMENTS I wish to express my appreciation to Dr. R. A. Fjeld and Dr. A. R. McFarland for their patience... LISTING APPENDIX C TABULATED RESULTS 58 60 72 VI TA 84 Vi LIST OF TABLES TABLE P age I Typical Flue Gas Compositions II Model Flue Gas Compositions 35 Coeff icients for Alpha particle Stopping Power Functions 59 Computed and Experimental...

  7. Greenhouse Gas and Particulate Emissions and Impacts from Cooking Technologies in Africa

    NASA Astrophysics Data System (ADS)

    Kammen, D. M.; Bailis, R.; Kituyi, E.; Ezzati, M.

    2003-12-01

    In much of Africa, the largest fraction of energy consumption occurs within the residential sector and is derived primarily from woodfuels burned in simple stoves with poor combustion characteristics. Many of the products of incomplete combustion (PICs) are damaging to human health, particularly when they are concentrated in poorly ventilated indoor environments. Incomplete combustion also has potentially harmful impacts on the climate. Prevalent PICs include methane, a potent greenhouse gas (GHG) that is among the pollutants subject to controls under the Kyoto Protocol as well as carbon monoxide (CO), non-methane hydrocarbons (NMHCs) and particulate matter (PM), which can all have an effect on climate, but are not subject to controls under Kyoto. In addition, when woodfuels are used at a rate that reduces standing stocks of trees over the medium or long term, the CO2 released by combustion also has an impact. The choice of stove and fuel technology can have a significant impact on the emission of GHGs as well as on human exposure to health damaging pollutants. In this paper we analyze the emissions of different household energy technologies on a life-cycle basis. We use emission factors to estimate the emissions associated with production, distribution and end-use of common household fuels and assess the likely impacts of these emissions on public health and the global environment. We focus largely on charcoal, a popular fuel in many sub-Saharan African countries. Charcoal is produced by heating wood in the absence of sufficient air for complete combustion to occur. This process removes moisture and most of the volatile compounds. The compounds driven off in the process consist of condensable tars as well as many gaseous hydrocarbons, including ~40 g CH4 per kg of charcoal produced. Combining upstream and end-use emissions, every meal cooked with charcoal has 2-10 times the global warming effect of cooking the same meal with firewood and 5-12 times the effect of cooking the same meal with LPG or kerosene. When charcoal is produced in large quantities, as it is in Africa, the net warming effect can exceed the impact from the "modern energy sector" (transportation and industry) by 50-100 percent, even if charcoal is produced on a sustainable cycle so that all of the wood harvested for charcoal production is allowed to regenerate. However, while charcoal may be worse than firewood with respect to greenhouse gas emissions, it is an improvement with respect to exposure to health damaging pollutants, particularly particulate matter (PM). Levels of PM in households using charcoal are over 90 percent lower than households using open wood fires (316 -(159) mg/m3 for households using charcoal in a common improved stove compared to 3764 (360) mg/m3) for households using wood in open fires: mean (standard error)). These differences in exposure are consistent with 30 and 50 percent reductions in the incidence of acute respiratory infection (ARI) in adults and children under 5 respectively. Reconciling the costs and benefits of different household energy technologies creates a difficult policy challenge, particularly with the severe budgetary and resource constraints that household consumers and government agencies face in sub-Saharan Africa.

  8. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...meters or flow instrumentation to determine flow through the particulate filters. These instruments...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, or a laminar flow element or an NIST traceable flow...

  9. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...meters or flow instrumentation to determine flow through the particulate filters. These instruments...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, or a laminar flow element or an NIST traceable flow...

  10. Study of medical isotope production facility stack emissions and noble gas isotopic signature using automatic gamma-spectra analysis platform

    NASA Astrophysics Data System (ADS)

    Zhang, Weihua; Hoffmann, Emmy; Ungar, Kurt; Dolinar, George; Miley, Harry; Mekarski, Pawel; Schrom, Brian; Hoffman, Ian; Lawrie, Ryan; Loosz, Tom

    2013-04-01

    The nuclear industry emissions of the four CTBT (Comprehensive Nuclear-Test-Ban Treaty) relevant radioxenon isotopes are unavoidably detected by the IMS along with possible treaty violations. Another civil source of radioxenon emissions which contributes to the global background is radiopharmaceutical production companies. To better understand the source terms of these background emissions, a joint project between HC, ANSTO, PNNL and CRL was formed to install real-time detection systems to support 135Xe, 133Xe, 131mXe and 133mXe measurements at the ANSTO and CRL 99Mo production facility stacks as well as the CANDU (CANada Deuterium Uranium) primary coolant monitoring system at CRL. At each site, high resolution gamma spectra were collected every 15 minutes using a HPGe detector to continuously monitor a bypass feed from the stack or CANDU primary coolant system as it passed through a sampling cell. HC also conducted atmospheric monitoring for radioxenon at approximately 200 km distant from CRL. A program was written to transfer each spectrum into a text file format suitable for the automatic gamma-spectra analysis platform and then email the file to a server. Once the email was received by the server, it was automatically analysed with the gamma-spectrum software UniSampo/Shaman to perform radionuclide identification and activity calculation for a large number of gamma-spectra in a short period of time (less than 10 seconds per spectrum). The results of nuclide activity together with other spectrum parameters were saved into the Linssi database. This database contains a large amount of radionuclide information which is a valuable resource for the analysis of radionuclide distribution within the noble gas fission product emissions. The results could be useful to identify the specific mechanisms of the activity release. The isotopic signatures of the various radioxenon species can be determined as a function of release time. Comparison of 133mXe and 133Xe activity ratios showed distinct differences between the closed CANDU primary coolant system and radiopharmaceutical production releases. According to the concept proposed by Kalinowski and Pistner (2006), the relationship between different isotopic activity ratios based on three or four radioxenon isotopes was plotted in a log-log diagram for source characterisation (civil vs. nuclear test). The multiple isotopic activity ratios were distributed in three distinct areas: HC atmospheric monitoring ratios extended to far left; the CANDU primary coolant system ratios lay in the middle; and 99Mo stack monitoring ratios for ANSTO and CRL were located on the right. The closed CANDU primary coolant has the lowest logarithmic mean ratio that represents the nuclear power reactor operation. The HC atmospheric monitoring exhibited a broad range of ratios spreading over several orders of magnitude. In contrast, the ANSTO and CRL stack emissions showed the smallest range of ratios but the results indicate at least two processes involved in the 99Mo productions. Overall, most measurements were found to be shifted towards the reactor domain. The hypothesis is that this is due to an accumulation of the isotope 131mXe in the stack or atmospheric background as it has the longest half-life and extra 131mXe emissions from the decay of 131I. The contribution of older 131mXe to a fresh release shifts the ratio of 133mXe/131mXe to the left. It was also very interesting to note that there were some situations where isotopic ratios from 99Mo production emissions fell within the nuclear test domain. This is due to operational variability, such as shorter target irradiation times. Martin B. Kalinowski and Christoph Pistner, (2006), Isotopic signature of atmospheric xenon released from light water reactors, Journal of Environmental Radioactivity, 88, 215-235.

  11. Compound Specific Concentration and Stable Isotope Ratio Measurements of Atmospheric Particulate Organic Matter and Gas Phase Nitrophenols

    NASA Astrophysics Data System (ADS)

    Busca, R.; Saccon, M.; Moukhtar, S.; Rudolph, J.

    2009-05-01

    Atmospheric particulate organic matter (POM) adversely affects health and climate. One of the still poorly understood sources of secondary organic matter (SOM) is the formation of secondary POM from the photo- oxidation of atmospheric volatile organic compounds (VOC). Nitrophenols, which are toxic semi-volatile compounds, are formed in the atmosphere by OH-radical initiated photo-oxidation of aromatic hydrocarbons, such as toluene. A method was developed to determine concentrations and stable carbon isotope ratios of particulate methyl nitrophenols in the atmosphere. This method has been used to quantify methyl nitrophenols, specifically 2-methyl-4-nitrophenol and 4-methyl-2-nitrophenol, found in atmospheric PM samples in trace quantities. Using this method, we conducted measurements of methyl nitrophenols in atmospheric PM in rural and suburban areas in Southern Ontario. The results of these measurements showed that the concentration of methyl nitrophenols in atmospheric PM is much lower than expected from the extrapolation of laboratory experiments and measured atmospheric toluene concentrations. In order to better understand the reasons for these findings, an analytical method for the analysis of nitrophenols in the gas phase is currently being developed. Similarly, the measurement technique is modified to allow analysis of other phenolic products of the oxidation of aromatic hydrocarbons in PM as well as in the gas phase. In this poster, sampling techniques for collection and GC-MS analysis of nitrophenols in gas phase and PM will be presented along with preliminary results from summer 2008 and spring 2009 studies.

  12. Flue gas conditioning for reducing suspended particulate matter from thermal power stations

    Microsoft Academic Search

    S. Shanthakumar; D. N. Singh; R. C. Phadke

    2008-01-01

    Increased population and industrial development demands sustainable electricity, the majority of which is produced by thermal power stations, which utilize coal as a fuel all over the world. Coal burning results in generation of large quantities of coal residues, which contains very fine particles that tend to become air-borne and which contribute to the formation of suspended particulate matter (SPM).

  13. Carboxylic acids in gas and PM2.5 particulate phase at a rural mountain site in northeastern United States

    NASA Astrophysics Data System (ADS)

    Hussain, M. M.; Khan, A. R.; Khwaja, H. A.

    2009-12-01

    Low molecular weight carboxylic acids are important constituents of the organic fraction of atmospheric particulate matter in rural and polluted regions. The knowledge on their source is sparse, however, and organic aerosols in general need to better characterized. Atmospheric gas- and particle-phase carboxylic acids (formic, acetic, pyruvic, glyoxalic, benzoaic, adipic, succinic, malonic, and oxalic) and related compounds were measured during August 2002 at a rural site, Whiteface Mountain, NY. Formic and acetic acids were present in the PM2.5 fraction and in the gas phase. Other seven carboxylic acids were below the detection limit in all samples. Formic and acetic acid were present in the atmosphere mostly in the gaseous form with less than 10% in the PM2.5 fraction. Concentrations of formic acid and acetic acid were in the 0.5 - 2.4 ppbv and 0.6 - 1.9 ppbv ranges, respectively. Formic-to-acetic acid ratios less than one (0.88) were recorded, likely due to an increase in acetic acid contribution from direct emissions. In the fine particulate mode (PM2.5 ) the concentrations for acetic acid and formic acid were 120 - 400 and 10 - 180 ng/m3 , respectively. Backward trajectory data indicate that air mass originated at midwestern region on August 5th and gradually moved towards north on August 9th. Correlation of formic acid with sulfate was investigated to interpret their possible secondary formation pathways. A strong correlation (0.73) was observed between formic acid and sulfate in PM2.5 particulates. Since the source of sulfate found at Whiteface Mountain widely accepted as anthropogenic, its association with formic acid indicated that the later might have anthropogenic source.

  14. Sampling of power plant stacks for air toxic emissions: Final report for Phases 1 and 2

    SciTech Connect

    NONE

    1995-04-28

    A test program to collect and analyze size-fractionated stack gas particulate samples for selected inorganic hazardous air pollutants (HAPs) was conducted . Specific goals of the program are (1) the collection of one-gram quantities of size-fractionated stack gas particulate matter for bulk (total) and surface chemical characterization, and (2) the determination of the relationship between particle size, bulk and surface (leachable) composition, and unit load. The information obtained from this program identifies the effects of unit load, particle size, and wet FGD system operation on the relative toxicological effects of exposure to particulate emissions. Field testing was conducted in two phases. The Phase I field program was performed over the period of August 24 through September 20, 1992, at the Tennessee Valley Authority Widows Creek Unit 8 Power Station, located near Stevenson (Jackson County), Alabama, on the Tennessee River. Sampling activities for Phase II were conducted from September 11 through October 14, 1993. Widows Creek Unit 8 is a 575-megawatt plant that uses bituminous coal averaging 3.7% sulfur and 13% ash. Downstream of the boiler, a venture wet scrubbing system is used for control of both sulfur dioxide and particulate emissions. There is no electrostatic precipitator (ESP) in this system. This system is atypical and represents only about 5% of the US utility industry. However, this site was chosen for this study because of the lack of information available for this particulate emission control system.

  15. Determination of nitrated polycyclic aromatic hydrocarbons in diesel particulate-related standard reference materials by using gas chromatography/mass spectrometry with negative ion chemical ionization.

    PubMed

    Bezabeh, Dawit Z; Bamford, Holly A; Schantz, Michele M; Wise, Stephen A

    2003-02-01

    Gas chromatography/mass spectrometry (GC/MS) with negative ion chemical ionization (NICI) detection was utilized for quantitative determination of nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) in diesel particulate-related standard reference materials (SRMs). Prior to GC/MS analysis, isolation of the nitro-PAHs from the complex diesel particulate extract was accomplished using solid phase extraction (SPE) and normal-phase liquid chromatographic (LC) fractionation using an amino/cyano stationary phase. Concentrations of eight to ten mononitro-PAHs and three dinitropyrenes were determined in three diesel particulate-related SRMs: SRM 1650a Diesel Particulate Matter, SRM 1975 Diesel Particulate Extract, and SRM 2975 Diesel Particulate Matter (Industrial Forklift). The results from GC/MS NICI using two different columns (5% phenyl methylpolysiloxane and 50% phenyl methylpolysiloxane) were compared to each other and to results from two other laboratories for selected nitro-PAHs. 1-Nitropyrene was the most abundant nitro-PAHs in each of the diesel particulate SRMs (19.8+/-1.1 micro g g(-1) particle in SRM 1650a and 33.1+/-0.6 micro g g(-1) particle in SRM 2975). Three dinitropyrene isomers were measured in SRM 1975 at 0.5-1.4 micro g g(-1) extract and in SRM 2975 at 1-3 micro g g(-1) particle. PMID:12589503

  16. Pyrolysis-gas chromatography/multiphoton ionization/time-of-flight mass spectrometry for the rapid and selective analysis of polycyclic aromatic hydrocarbons in aerosol particulate matter.

    PubMed

    Sakurai, Shunsuke; Uchimura, Tomohiro

    2014-01-01

    Gas chromatography/multiphoton ionization/time-of-flight mass spectrometry (GC/MPI/TOFMS) coupled with a Curie-point pyrolyzer as a sample introduction technique was applied for the rapid and selective analysis of the polycyclic aromatic hydrocarbons (PAHs) that are a part of aerosol particulate matter. Increasing the operating temperature of the pyrolyzer also increased the number of observed peaks, but the peak areas of a few PAHs decreased due to thermal decomposition. In the present study, more than 100 peaks were confirmed using 0.3 mg of an aerosol particulate matter, and further sensitive detection would be achievable. The advantages of MPI/TOFMS, such as optical selectivity and simultaneous determination properties, allowed the trace analysis of highly complicated particulate matter-even in the absence of pretreatment. Therefore, this method would help elucidate the origin of particulate matter when sampling from different points for short periods of time. PMID:25213817

  17. Slip stacking

    SciTech Connect

    Kiyomi Koba and James Steimel

    2002-09-19

    We have started beam studies for ''slip stacking''[1] in the Main Injector in order to increase proton intensity on a target for anti-proton production. It has been verified that the system for slip stacking is working with low intensity beam. For a high intensity operation, we are developing a feedback[2][3] and feedforward system.

  18. Stacked generalization

    Microsoft Academic Search

    David H. Wolpert

    1992-01-01

    : This paper introduces stacked generalization, a scheme for minimizing the generalizationerror rate of one or more generalizers. Stacked generalization works by deducing the biases of thegeneralizer(s) with respect to a provided learning set. This deduction proceeds by generalizing ina second space whose inputs are (for example) the guesses of the original generalizers when taughtwith part of the learning set

  19. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Cornell, L.P.; Keyvani, M.; Neyman, M. (Helipump Corp., Cleveland, OH (USA)); Helfritch, D.J. (Research-Cottrell, Inc., Somerville, NJ (USA). Environmental Services and Technologies Div.)

    1990-04-17

    The process control SO{sub x}, NO{sub x}, and particulate emission from coal combustion flue gases. It is based on a solid-state, electrochemical reactor which converts NO{sub x} and SO{sub 2} to nitrogen, sulfur, and oxygen. Sulfur is condensed downstream at a lower temperature. Particulates are removed with a filter or electrostatic precipitator. The process utilizes no other material input (flue gas is the only fluid), has no moving parts, and produces no sludge(s). The reactor consists of an electrochemical cell where the electrolyte is a solid oxygen ion conducting ceramic such as stabilized ceria or zirconia and the electrodes are electronically conductive material(s). Porous metal such as silver or gold were used as electrodes in the experimental work. Acceptable reduction rates and electric power requirements for sulfur dioxide and nitrogen oxide removal were obtained in up to 1% oxygen with ruthenium and strontium ruthenate electrocatalysts. Electrocatalytic improvements are needed for higher oxygen concentrations, with the NO reduction rates and efficiencies being most sensitive to oxygen concentration. The best electrocatalysts were ruthenium and the perovskite strontium ruthenate. 37 refs., 23 figs., 26 tabs.

  20. Pyrolysis-gas chromatography/mass spectrometry analyses of biological particulates collected during recent space shuttle missions

    NASA Technical Reports Server (NTRS)

    Matney, M. L.; Limero, T. F.; James, J. T.

    1994-01-01

    Biological particulates collected on air filters during shuttle missions (STS-40 and STS-42) were identified using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). A method was developed for identifying the atmospheric particles and their sources through the analysis of standard materials and the selection of "marker" compounds specific to the particle type. Pyrolysis spectra of biological standards were compared with those of airborne particles collected during two space shuttle missions; marker compounds present in the shuttle particle spectra were matched with those of the standards to identify the source of particles. Particles of 0,5--1-mm diameter and weighing as little as 40 micrograms could be identified using this technique. The Py-GC/MS method identified rat food and soilless plant-growth media as two sources of particles collected from the shuttle atmosphere during flight.

  1. GAS CHROMATOGRAPHY/MATRIX ISOLATION-FOURIER TRANSFORM INFRARED SPECTROMETRY FOR THE IDENTIFICATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN URBAN AIR PARTICULATE MATTER

    EPA Science Inventory

    The capabilities of gas chromatography/matrix isolation-Fourier transform infrared (GC/MI-FTIR) spectrometry for detecting and identifying polycyclic aromatic hydrocarbons (PAHs) in urban air particulate matter are demonstrated. he ability of GC/MI-FTIR to discriminate between PA...

  2. Process for cooling particulate coal

    Microsoft Academic Search

    Bonnecaze

    1983-01-01

    A process is disclosed for drying particulate coal by passing a heated gas through the particulate coal in a heating zone and thereafter cooling the dried particulate coal in a cooling zone, an improvement comprising the addition of a controlled quantity of water to the dried coal in the cool zone so that the coal is cooled by evaporation of

  3. Interim Particulate Matter Test Method for the Determination of Particulate Matter from Gas Turbine Engines, SERDP Project WP-1538 Final Report

    EPA Science Inventory

    Under Project No. WP-1538 of the Strategic Environmental Research and Development Program, the U. S. Air Force's Arnold Engineering Development Center (AEDC) is developing an interim test method for non-volatile particulate matter (PM) specifically for the Joint Strike Fighter (J...

  4. Evaluation of methods for measuring particulate matter emissions from gas turbines.

    PubMed

    Petzold, Andreas; Marsh, Richard; Johnson, Mark; Miller, Michael; Sevcenco, Yura; Delhaye, David; Ibrahim, Amir; Williams, Paul; Bauer, Heidi; Crayford, Andrew; Bachalo, William D; Raper, David

    2011-04-15

    The project SAMPLE evaluated methods for measuring particle properties in the exhaust of aircraft engines with respect to the development of standardized operation procedures for particulate matter measurement in aviation industry. Filter-based off-line mass methods included gravimetry and chemical analysis of carbonaceous species by combustion methods. Online mass methods were based on light absorption measurement or used size distribution measurements obtained from an electrical mobility analyzer approach. Number concentrations were determined using different condensation particle counters (CPC). Total mass from filter-based methods balanced gravimetric mass within 8% error. Carbonaceous matter accounted for 70% of gravimetric mass while the remaining 30% were attributed to hydrated sulfate and noncarbonaceous organic matter fractions. Online methods were closely correlated over the entire range of emission levels studied in the tests. Elemental carbon from combustion methods and black carbon from optical methods deviated by maximum 5% with respect to mass for low to medium emission levels, whereas for high emission levels a systematic deviation between online methods and filter based methods was found which is attributed to sampling effects. CPC based instruments proved highly reproducible for number concentration measurements with a maximum interinstrument standard deviation of 7.5%. PMID:21425830

  5. Trace Gas and Particulate Observations at the Marine Boundary Layer Site near Ucluelet on Vancouver Island

    NASA Astrophysics Data System (ADS)

    Schiller, C. L.; Vingarzan, R.; Jones, K.; Leaitch, R.; Macdonald, A.; Mihele, C.; Graham, M.; Reid, K.

    2011-12-01

    In May 2010, a Marine Boundary Layer (MBL) station was established on the west coast of Vancouver Island near Ucluelet, B.C. Prevailing winds at the station are from the E to SE in the fall and winter and from the W to NW in the spring and summer. Observations of both trace gases (CO, O3, NOx, CO2, SO2...) as well as particulate measurements will be examined for background concentration of this MBL site and a number of interesting events including ozone depletion in the MBL and emission ratios from observed ship plumes both fresh and aged. Ozone concentrations have been observed to be reduced to 10-15ppb in the absence of NOx during the depletion events from background levels. The air measured at the site can be impacted by ships in the shipping lanes that converge into the Juan de Fuca Strait headed for Vancouver and Seattle as well as local fishing vessels. Emission ratios of both aged and fresh plumes will be examined.

  6. Particulate Scrubbing Performance of the High Level Caves Off-Gas System

    SciTech Connect

    Wright, G.T.

    2001-08-16

    Performance tests were conducted at the ETF using off-gas from the Small Cylindrical Melter (SCM) -2. The purpose of these tests was to develop data for comparing small and full scale equipment performance. This reports discusses those test results.

  7. Stacking Water

    NSDL National Science Digital Library

    In this lesson, students become familiar with how ocean water forms density-stratified layers in many places. They design and carry out a series of tests to show how water masses of four different densities interact, using clear straws to stack colored water of different salinities. Temperature is varied to increase the differences in density of each water sample.

  8. Stacking Up

    ERIC Educational Resources Information Center

    Naylor, Jim

    2005-01-01

    Chimneys and stacks appear to be strong and indestructible, but chimneys begin to deteriorate from the moment they are built. Early on, no signs are apparent; but deterioration accelerates in subsequent years, and major repairs are soon needed instead of minor maintenance. With proper attention, most structures can be repaired and continue to…

  9. Application of multicriteria decision making methods to compression ignition engine efficiency and gaseous, particulate, and greenhouse gas emissions.

    PubMed

    Surawski, Nicholas C; Miljevic, Branka; Bodisco, Timothy A; Brown, Richard J; Ristovski, Zoran D; Ayoko, Godwin A

    2013-02-19

    Compression ignition (CI) engine design is subject to many constraints, which present a multicriteria optimization problem that the engine researcher must solve. In particular, the modern CI engine must not only be efficient but must also deliver low gaseous, particulate, and life cycle greenhouse gas emissions so that its impact on urban air quality, human health, and global warming is minimized. Consequently, this study undertakes a multicriteria analysis, which seeks to identify alternative fuels, injection technologies, and combustion strategies that could potentially satisfy these CI engine design constraints. Three data sets are analyzed with the Preference Ranking Organization Method for Enrichment Evaluations and Geometrical Analysis for Interactive Aid (PROMETHEE-GAIA) algorithm to explore the impact of (1) an ethanol fumigation system, (2) alternative fuels (20% biodiesel and synthetic diesel) and alternative injection technologies (mechanical direct injection and common rail injection), and (3) various biodiesel fuels made from 3 feedstocks (i.e., soy, tallow, and canola) tested at several blend percentages (20-100%) on the resulting emissions and efficiency profile of the various test engines. The results show that moderate ethanol substitutions (~20% by energy) at moderate load, high percentage soy blends (60-100%), and alternative fuels (biodiesel and synthetic diesel) provide an efficiency and emissions profile that yields the most "preferred" solutions to this multicriteria engine design problem. Further research is, however, required to reduce reactive oxygen species (ROS) emissions with alternative fuels and to deliver technologies that do not significantly reduce the median diameter of particle emissions. PMID:23343018

  10. Environmental assessment of three egg production systems - Part II. Ammonia, greenhouse gas, and particulate matter emissions.

    PubMed

    Shepherd, T A; Zhao, Y; Li, H; Stinn, J P; Hayes, M D; Xin, H

    2015-03-01

    As an integral part of the Coalition for Sustainable Egg Supply (CSES) Project, this study simultaneously monitored air emissions of 3 commercially operated egg production systems at the house level and associated manure storage over 2 single-cycle flocks (18 to 78 wk of age). The 3 housing systems were 1) a conventional cage house (CC) with a 200,000-hen capacity (6 hens in a cage at a stocking density of 516 cm(2)/hen), 2) an enriched colony house (EC) with a 50,000-hen capacity (60 hens per colony at a stocking density of 752 cm(2)/hen), and 3) an aviary house (AV) with a 50,000-hen capacity (at a stocking density of 1253 to 1257 cm(2)/hen). The 3 hen houses were located on the same farm and were populated with Lohmann white hens of the same age. Indoor environment and house-level gaseous (ammonia [NH3] and greenhouse gasses [GHG], including carbon dioxide [CO2], methane [CH4], and nitrous oxide [N2O]) and particulate matter (PM10, PM2.5) emissions were monitored continually. Gaseous emissions from the respective manure storage of each housing system were also monitored. Emission rates (ERs) are expressed as emission quantities per hen, per animal unit (AU, 500 kg live BW), and per kilogram of egg output. House-level NH3 ER (g/hen/d) of EC (0.054) was significantly lower than that of CC (0.082) or AV (0.112) (P < 0.05). The house-level CO2 ER (g/hen/d) was lower for CC (68.3) than for EC and AV (74.4 and 74.0, respectively), and the CH4 ER (g/hen/d) was similar for all 3 houses (0.07 to 0.08). The house-level PM ER (mg/hen/d), essentially representing the farm-level PM ER, was significantly higher for AV (PM10 100.3 and PM2.5 8.8) than for CC (PM10 15.7 and PM2.5 0.9) or EC (PM10 15.6 and PM2.5 1.7) (P < 0.05). The farm-level (house plus manure storage) NH3 ER (g/hen/d) was significantly lower for EC (0.16) than for CC (0.29) or AV (0.30) (P < 0.05). As expected, the magnitudes of GHG emissions were rather small for all 3 production systems. Data from this study enable comparative assessment of conventional vs. alternative hen housing systems regarding air emissions and enhance the U.S. national air emissions inventory for farm animal operations. PMID:25737568

  11. Testing of a shrouded, short mixing stack gas eductor model using high temperature primary flow. Master's thesis

    Microsoft Academic Search

    Eick

    1982-01-01

    An existing apparatus for testing models of gas eductor systems using high temperature primary flow was redesigned and modified to provide improved control and performance over a wide range of gas temperatures and flow rates. Pumping coefficient, temperature, and pressure data were recorded for two gas eductor system models. The first, previously tested under hot flow conditions, consisted of a

  12. Foam formation and mitigation in a three-phase gas-liquid-particulate system.

    PubMed

    Vijayaraghavan, Krishna; Nikolov, Alex; Wasan, Darsh

    2006-11-16

    Foaming is of great concern in a number of industrial processes involving three-phase gas-liquid-finely divided solid systems such as those encountered in the vitrification of highly radioactive nuclear waste slurries and sludges. Recent work has clearly shown that the surface properties of the particles such as hydrophilicity, hydrophobicity or biphilicity (i.e. partially wetted by water) are the cause of foamability and foam stability. The literature data on particles causing foaminess and foam stability in the absence of any surfactant are rather scarce. This paper presents experimental observations on aqueous foams with polyhedral structures containing over 90% air generated due to the presence of irregularly-shaped fine crystalline particles of sodium chloride which were modified into amphiphilic particles by physical adsorption of a cationic surfactant. Cross-polarized light microscopy was used to visualize the physical adsorption of the surfactant on the crystal surface. It is shown that these biphilic or amphiphilic particles attach to the air bubble surface and prevent the coalescence of bubbles, thereby extending the life of the foam. The foaming power of solid particles increases with an increase in the concentration of amphiphilic particles, and a maximum in foaminess is observed which is due to two competing effects. Amphiphilic particles promote foamability by attachment to the bubble surfaces as individual particles and foam inhibition due to the clustering or flocculation of particles in the bulk at high particle concentrations. We studied the adsorption of amphiphilic particles at a planar air-water surface and found that the degree of foamability correlates well with the particle coverage (i.e. adsorption density) at the air-liquid surface. An exploratory study was also conducted using an antifoam recently developed by IIT researchers to mitigate foaming in particle-laden gas-liquid systems. PMID:16997269

  13. Characterization of polycyclic aromatic hydrocarbon emissions in the particulate and gas phase from smoldering mosquito coils containing various atomic hydrogen/carbon ratios.

    PubMed

    Yang, Tzu-Ting; Lin, Shaw-Tao; Lin, Tser-Sheng; Chung, Hua-Yi

    2015-02-15

    The polycyclic aromatic hydrocarbon emissions in particulate and gas phases generated from smoldering mosquito coils containing various atomic H/C ratios were examined. Five types of mosquito coils were burned in a test chamber with a total airflow rate of 8.0 L/min at a constant relative humidity and temperature. The concentrations of individual PAHs were determined using the GC/MS technique. Among the used mosquito coils, the atomic H/C ratio ranged from 1.23 to 1.57, yielding total mass, gaseous, and particulate PAH emission factors of 28.17-78.72 mg/g, 26,139.80-35,932.98 and 5735.22-13,431.51 ng/g, respectively. The various partitions of PAHs in the gaseous and particulate phases were in the ranges, 70.26-83.70% and 16.30-29.74% for the utilized mosquito coils. The carcinogenic potency of PAH emissions in the particulate phase (203.82-797.76 ng/g) was approximately 6.92-25.08 times higher than that of the gaseous phase (26.27-36.07 ng/g). Based on the analyses of PAH emissions, mosquito coils containing the lowest H/C ratio, a low oxygen level, and additional additives (i.e., CaCO3) are recommended for minimizing the production of total PAH emission factors and carcinogenic potency. PMID:25460974

  14. Real-time analysis of metals in stack gas using argon/air inductively coupled plasma with optical emission spectrometry

    NASA Astrophysics Data System (ADS)

    Meyer, Gerhard; Seltzer, Michael D.

    1999-02-01

    The design and operation of an instrument capable of continuous, real-time detection of hazardous air pollutant metals in the effluent of boilers, incinerators, and furnaces is reported. A commercially available inductively coupled argon plasma spectrometer, modified for introduction of sample air, provides sensitivity for several metals comparable to that of EPA-approved manual methods, with an analysis result reported every 1 to 2 minutes. Achievable detection limits for the present list of hazardous air pollutant metals range from 0.1 to 20 (mu) g/dry standard cubic meter. Air is isokinetically extracted from a stack or duct and introduced into the argon plasma through an innovative sample transport interface. Data is reported after every measurement cycle and immediately archived to a control computer, where the information is available to a local area network. The entire instrument is automated, and is enclosed in a shelter that can be placed as near as possible to the stack. The measurement of sample losses in the transport line is also discussed.

  15. Particulate hot gas stream cleanup technical issues. Quarterly report, January--March 1996

    SciTech Connect

    NONE

    1996-05-21

    To identify which ash characteristics can lead to problems with filtration, the authors have assembled 235 ash samples from eleven facilities involved in METC`s HGCU program. They have analyzed many of these ashes with a variety of laboratory tests. Physical attributes of the particles that they have examined include size distribution, specific surface area, particle morphology, and bulk ash cohesivity and permeability. They have also performed a range of chemical analyses on these ashes, as well as characterizations of agglomerates of ash removed from filter vessels at Tidd and Karhula. They are in the process of assembling the data obtained in these studies into an interactive data base which will help the manufacturers and operators of high-temperature barrier filters tailor their designs and operations to the specific characteristics of the ashes they are collecting. In order to understand the thermal and mechanical behavior of the various types of ceramic materials used in hot gas filtration, they have been performing hoop and axial tensile tests, thermal expansion, compression, and creep evaluations of these materials at temperatures up to 1,800 F. Nondestructive testing methods they perform on filter specimens include density and ultrasonic velocity. To date they have evaluated various characteristics of Dupont/Lanxide PRD-66, Dupont composite, 3M composite, IF and P Fibrosics, Refractron, Schumacher, and Blasch alumina mullite materials.

  16. Particulate hot gas stream cleanup technical issues. Quarterly report, April 1 - June 30, 1996

    SciTech Connect

    NONE

    1996-12-31

    This is the seventh in a series of quarterly reports describing the activities performed for this project. Our analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic barrier filter elements. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFs) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task 1 during the past quarter, we received and analyzed a hopper ash sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota`s Energy and Environmental Research Center (UNDEERC). We also received six ash samples from the Ahlstrom 10 MWt Pressurized Fluidized Circulating Fluid Bed (PCFB) facility located at Karhula, Finland. We selected one of the filter cake ashes from this batch of samples for detailed analyses. We continued our work on the HGCU data base we are constructing in Microsoft Access{reg_sign}. We have been entering a variety of information into the data base, including numerical values, short or long text entries, and photographs. Task 2 efforts during the past quarter focused on hoop tensile testing of Schumacher FT20 and Refractron candle filter elements removed from the Karhula APF after {approximately}540 hours of service.

  17. Particulate hot gas stream cleanup technical issues. Quarterly report, January 1--March 31, 1998

    SciTech Connect

    NONE

    1998-08-01

    The analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance studied under this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFs) and to relate these ash properties to the operation and performance of these filters and their components. APF operations have also been limited by the strength and durability of the ceramic materials that have served as barrier filters for the capture of entrained HGCU ashes. Task 2 concerns testing and failure analyses of ceramic filter elements currently used in operating APFs and the characterization and evaluation of new ceramic materials. Task 1 research activities during the past quarter included characterizations of samples collected during a site visit on January 20 to the Department of Energy/Southern Company Services Power Systems Development Facility (PSDF). Comparisons were made between laboratory analyses of these PSDF ashes and field data obtained from facility operation. In addition, selected laboratory techniques were reviewed to assess their reproducibility and the influence of non-ideal effects and differences between laboratory and filter conditions on the quantities measured. Further work on the HGCU data base is planned for the next quarter. Two Dupont PRD-66 candle filters, one McDermott candle filter, one Blasch candle filter, and one Specific Surfaces candle filter were received at SRI for testing. A test plan and cutting plan for these candles was developed. Acquisition of two of the Dupont PRD-66 candle filters will allow candle-to-candle variability to be examined.

  18. Composition, toxicity, and mutagenicity of particulate and semivolatile emissions from heavy-duty compressed natural gas-powered vehicles.

    PubMed

    Seagrave, JeanClare; Gigliotti, Andrew; McDonald, Jacob D; Seilkop, Steven K; Whitney, Kevin A; Zielinska, Barbara; Mauderly, Joe L

    2005-09-01

    Particulate matter (PM) and vapor-phase semivolatile organic compounds (SVOC) were collected from three buses fueled by compressed natural gas. The bus engines included a well-functioning, conventional engine; a "high emitter" engine; and a new technology engine with an oxidation catalyst. Chemical analysis of the emissions showed differences among these samples, with the high emitter sample containing markers of engine oil constituents. PM + SVOC samples were also collected for mutagenicity and toxicity testing. Extraction efficiencies from the collection media were lower than for similarly collected samples from gasoline or diesel vehicles. Responses to the recovered samples were compared on the basis of exhaust volume, to incorporate the emission rates into the potency factors. Mutagenicity was assessed by Salmonella reverse mutation assay. Mutagenicity was greatest for the high emitter sample and lowest for the new technology sample. Metabolic activation reduced mutagenicity in strain TA100, but not TA98. Toxicity, including inflammation, cytotoxicity, and parenchymal changes, was assessed 24 h after intratracheal instillation into rat lungs. Lung responses were generally mild, with little difference between the responses to equivalent volumes of emissions from the normal emitter and the new technology, but greater responses for the high emitter. These emission sample potencies are further compared on the basis of recovered mass with previously reported samples from normal and high-emitter gasoline and diesel vehicles. While mutagenic potencies for the CNG emission samples were similar to the range observed in the gasoline and diesel emission samples, lung toxicity potency factors were generally lower than those for the gasoline and diesel samples. PMID:15976195

  19. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...meters or flow instrumentation to determine flow through the particulate filters, methanol...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, or a laminar flow element or an NBS traceable flow...

  20. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...meters or flow instrumentation to determine flow through the particulate filters, methanol...device in series with the instrument. A critical flow orifice, a bellmouth nozzle, or a laminar flow element or an NBS traceable flow...

  1. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty...not requiring particulate emissions measurements. (a)...

  2. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty...not requiring particulate emissions measurements. (a)...

  3. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty...not requiring particulate emissions measurements. (a)...

  4. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty...not requiring particulate emissions measurements. (a)...

  5. Regenerative process and system for the simultaneous removal of particulates and the oxides of sulfur and nitrogen from a gas stream

    DOEpatents

    Cohen, M.R.; Gal, E.

    1993-04-13

    A process and system are described for simultaneously removing from a gaseous mixture, sulfur oxides by means of a solid sulfur oxide acceptor on a porous carrier, nitrogen oxides by means of ammonia gas and particulate matter by means of filtration and for the regeneration of loaded solid sulfur oxide acceptor. Finely-divided solid sulfur oxide acceptor is entrained in a gaseous mixture to deplete sulfur oxides from the gaseous mixture, the finely-divided solid sulfur oxide acceptor being dispersed on a porous carrier material having a particle size up to about 200 microns. In the process, the gaseous mixture is optionally pre-filtered to remove particulate matter and thereafter finely-divided solid sulfur oxide acceptor is injected into the gaseous mixture.

  6. Regenerative process and system for the simultaneous removal of particulates and the oxides of sulfur and nitrogen from a gas stream

    DOEpatents

    Cohen, Mitchell R. (Troy, NY); Gal, Eli (Lititz, PA)

    1993-01-01

    A process and system for simultaneously removing from a gaseous mixture, sulfur oxides by means of a solid sulfur oxide acceptor on a porous carrier, nitrogen oxides by means of ammonia gas and particulate matter by means of filtration and for the regeneration of loaded solid sulfur oxide acceptor. Finely-divided solid sulfur oxide acceptor is entrained in a gaseous mixture to deplete sulfur oxides from the gaseous mixture, the finely-divided solid sulfur oxide acceptor being dispersed on a porous carrier material having a particle size up to about 200 microns. In the process, the gaseous mixture is optionally pre-filtered to remove particulate matter and thereafter finely-divided solid sulfur oxide acceptor is injected into the gaseous The government of the United States of America has rights in this invention pursuant to Contract No. DE-AC21-88MC 23174 awarded by the U.S. Department of Energy.

  7. Zinc paddlewheel dimers containing a strong ?···? stacking supramolecular synthon: designed single-crystal to single-crystal phase changes and gas/solid guest exchange.

    PubMed

    Reger, Daniel L; Debreczeni, Agota; Smith, Mark D

    2011-11-21

    The ligand 4-(1,8-naphthalimido)benzoate, L(C4)(-), containing a linear link between the strong ?···? stacking 1,8-naphthalimide supramolecular synthon and the carboxylate donor group, reacts with Zn(O(2)CCH(3))(2)(H(2)O)(2) in the presence of dimethylsulfoxide (DMSO) to yield [Zn(2)(L(C4))(4)(DMSO)(2)]·2(CH(2)Cl(2)). This compound contains the "paddlewheel" Zn(2)(O(2)CR)(4) secondary building unit (SBU) that organizes the rigid phenylene and naphthalimide rings of the carboxylate ligands in a square arrangement. The supramolecular architecture is dominated by ?···? stacking interactions between naphthalimide rings of one dimer with four adjacent dimers, essentially at right angles, forming an open three-dimensional network structure. Two symmetry equivalent networks of this type interpenetrate generating overall a densely packed three-dimensional, 2-fold interpenetrated architecture in which the CH(2)Cl(2) solvate molecules are trapped in isolated pockets. Upon cooling, single crystals of [Zn(2)(L(C4))(4)(DMSO)(2)]·2(CH(2)Cl(2)) undergo two distinct crystallographic phase transitions, as characterized by X-ray diffraction at different temperatures, without loss of crystallinity. These two new phases have supramolecular structures very similar to the room temperature structure, but changes in the ordering of the CH(2)Cl(2) solvate cause shifting of the naphthalimide rings and a lowering of the symmetry. Crystals of [Zn(2)(L(C4))(4)(DMSO)(2)]·2(CH(2)Cl(2)) undergo a single-crystal to single-crystal gas/solid guest exchange upon exposure to atmospheric moisture, or faster if placed under vacuum or heated under dry gas to 100 °C, followed by atmospheric moisture, to yield [Zn(2)(L(C4))(4)(DMSO)(2)]·3.9(H(2)O). The molecular and supramolecular structures of this new compound are very similar to the dichloromethane adduct, with now the water molecules encapsulated into the framework. The remarkable feature of both the phase changes and exchange of solvates is that this robust network is not porous; local distortions (ring slippage and tilting changes) of the ?···? stacking interactions of the naphthalimide rings that organize these structures allow these changes to take place without the loss of crystallinity. The complexes [Zn(2)(L(C4))(4)(DMSO)(2)]·2(CH(2)Cl(2)) and [Zn(2)(L(C4))(4)(DMSO)(2)]·3.9(H(2)O) show green emission in the solid state. PMID:22029900

  8. Modular fuel-cell stack assembly

    DOEpatents

    Patel, Pinakin (Danbury, CT)

    2010-07-13

    A fuel cell assembly having a plurality of fuel cells arranged in a stack. An end plate assembly abuts the fuel cell at an end of said stack. The end plate assembly has an inlet area adapted to receive an exhaust gas from the stack, an outlet area and a passage connecting the inlet area and outlet area and adapted to carry the exhaust gas received at the inlet area from the inlet area to the outlet area. A further end plate assembly abuts the fuel cell at a further opposing end of the stack. The further end plate assembly has a further inlet area adapted to receive a further exhaust gas from the stack, a further outlet area and a further passage connecting the further inlet area and further outlet area and adapted to carry the further exhaust gas received at the further inlet area from the further inlet area to the further outlet area.

  9. [Genotoxicity of stack gas condensates of Bavarian waste incineration plants. III. Emission monitoring with a simple UDS assay using the human lung cell lines NCI-H 322 and 358].

    PubMed

    Raabe, F; Wichmann, G; Dautzenberg, D; Lierse, C; Zluticky, J; Metzner, G; Mücke, W

    1999-02-01

    For the validation of the genotoxicity testing on stack gas condensates from waste incineration plants using bacterial short time tests (15), a modified UDS assay with the lung cell lines NCI-H 322 and 358 was developed. The UDS assay is more sensitive than the SOS chromotest and discriminates better between the negative or weakly positive and the clearly positive samples. It has a high sensitive and specificity and also accuracy, is practicable in a comparatively simple, speedy and reasonably priced manner and is therefore appropriate for an emission monitoring similar to simple bacterial short time tests. Especially in strongly concentrated crude and clean gas condensates, maximal induction factors were seen in the range of strong UDS inducers. From 55 samples on 16 incineration plants tested in the years 1992 to 1995, in 48 we found weak to strong UDS inductions in at least one of the two test cell lines. From three plants examined continuously in this period only two emitted stack gases with constantly low genotoxicity at the end of sampling. 5 clean gas condensates, that were taken in random samples from 3 other plants in the period 1994 to 1995, proved to be non-genotoxic in the UDS assay. However, one of these plants emitted stack gases with high cytotoxicity, which might have masked UDS-inducing single substances. It is not possible to make a statement on the human toxicological relevance. However, a clearly positive development towards more harmless stack gas condensates was established. A definite correlation could not be shown between the chemical analysis of the detected cancerogenic organic single substances of the samples and the detected UDS inductions. Further investigations for finding strong UDS inducers from the substance spectrum of municipal stack gas emissions are necessary. PMID:10084205

  10. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Calculations; particulate emissions... § 86.145-82 Calculations; particulate emissions...dilute exhaust sample gas meter or flow instrument, in Hg...at the inlet to the gas meter or flow instrument,...

  11. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Calculations; particulate emissions... § 86.145-82 Calculations; particulate emissions...dilute exhaust sample gas meter or flow instrument, in Hg...at the inlet to the gas meter or flow instrument,...

  12. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Calculations; particulate emissions... § 86.145-82 Calculations; particulate emissions...dilute exhaust sample gas meter or flow instrument, in Hg...at the inlet to the gas meter or flow instrument,...

  13. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Calculations; particulate emissions... § 86.145-82 Calculations; particulate emissions...dilute exhaust sample gas meter or flow instrument, in Hg...at the inlet to the gas meter or flow instrument,...

  14. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Calculations; particulate emissions... § 86.145-82 Calculations; particulate emissions...dilute exhaust sample gas meter or flow instrument, in Hg...at the inlet to the gas meter or flow instrument,...

  15. Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.

    PubMed

    Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C

    2011-01-01

    The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns. PMID:21126058

  16. Reactor for dry flue gas desulfurization

    SciTech Connect

    Camp, J.V.; Baran, S.J.

    1986-04-29

    A method is described for cleansing waste stack gases containing sulfur oxides from a generator of such gases, the generator being operable at a predetermined load and a turndown from such load. The method consists of: introducing the waste stack gases into a reaction zone; introducing an aqueous slurry containing an alkaline reagent into the zone for reaction of the reagent with the sulfur oxides, to produce an effluent stream containing precipitated particulate; passing the effluent stream from the reaction zone to a filter zone and filtering the precipitated particulate from the stream in the filter zone; controlling the ratio of aqueous slurry flow to waste stack gases to maintain a relatively dry flow in the filter zone; determining the level of waste stack gas flow velocity required for optimum mixing in the reaction zone of sulfur oxides and alkaline reagent; and varying the area of flow of waste stack gases at the point of introduction of such gases into the reaction zone with turndown in generator load to maintain the gas flow velocity at or near the level.

  17. Fuel cell stack arrangements

    DOEpatents

    Kothmann, Richard E. (Churchill Boro, PA); Somers, Edward V. (Murrysville, PA)

    1982-01-01

    Arrangements of stacks of fuel cells and ducts, for fuel cells operating with separate fuel, oxidant and coolant streams. An even number of stacks are arranged generally end-to-end in a loop. Ducts located at the juncture of consecutive stacks of the loop feed oxidant or fuel to or from the two consecutive stacks, each individual duct communicating with two stacks. A coolant fluid flows from outside the loop, into and through cooling channels of the stack, and is discharged into an enclosure duct formed within the loop by the stacks and seals at the junctures at the stacks.

  18. Physics and chemistry of E-beam stack gas processing. Final report, 20 September 1982-14 January 1984

    SciTech Connect

    Slater, R.

    1983-10-01

    The purpose of this program is to investigate some of the basic physics and chemistry of the electron beam induced NO/sub x/ and SO/sub x/ removal process. The program involves both kinetic modelling and diagnostic development. The development of an adequate kinetic model is necessary in order to scale the laboratory results, which are currently available, to process conditions closer to those that will be encountered at full scale operation. It is also necessary in order to place the laboratory data on a firm theoretical foundation. The development of real time optical diagnostics is a necessary supporting task for these goals in order to obtain kinetic data on some of the myriad of species that are present in this hostile environment (X-rays present; hot, acidic gas) which is difficult to access by conventional methods. This particular NO/sub x//SO/sub x/ removal process involves the irradiation of combustion products t temperatures around 100/sup 0/C with a beam of high energy electrons. The current study expands upon the mechanistic studies. A detailed kinetic model is described which includes all the necessary assumptions that enter in order to take the very large number of possible processes that occur in e-beam irradiated mixtures and reduce them to some tractable number. Quantitative comparisons are then made between the kinetic model and experimental data. Another phase of this program is the development of laser diagnostics to probe various species in the irradiated flue gas. The experimental phase of program is first described including a discussion of our e-beam facility and the methods used to accurately measure energy deposition. A description of the laser diagnostics follows. 37 references, 22 figures, 7 tables.

  19. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    Microsoft Academic Search

    Glenn C. England

    2004-01-01

    In 1997, the United States Environmental Protection Agency (EPA) promulgated new National Ambient Air Quality Standards (NAAQS) for particulate matter, including for the first time particles with aerodynamic diameter smaller than 2.5 micrometers (μm) referred to as PM2.5. PM2.5 in the atmosphere also contributes to reduced atmospheric visibility, which is the subject of existing rules for siting emission sources near

  20. Determination of nitrated polynuclear aromatic hydrocarbons in particulate extracts by capillary column gas chromatography with nitrogen selective detection

    Microsoft Academic Search

    M. C. Paputa-Peck; R. S. Marano; Dennis. Schuetzle; T. L. Riley; C. V. Hampton; T. J. Prater; L. M. Skewes; T. E. Jensen; P. H. Ruehle; L. C. Bosch

    1983-01-01

    The highly complex matrix of a diesel particulate extract was analyzed for nitrated polynuclear aromatic hydrocarbons (nitro-PAH) by use of fused-silica capillary column GC\\/thermionic nitrogen-phosphorus (GC\\/NPD) analysis of HPLC fractions. These samples were found to contain at least 100 nitro-PAH. Positive isomer identification for 17 nitro-PAH has been made utilizing the GC retention times of authentic standards and low- and

  1. Fine particulate capture device

    NASA Technical Reports Server (NTRS)

    Peterson, V. S.; Siewert, R. D. (inventors)

    1979-01-01

    To capture fine particulate matter in a gas such as air, a dielectric fluid is directed to the center of whichever face of a rotating disc is exposed to the air flow. The disc is comprised of two or more segments which bear opposite electrostatic potentials. As the dielectric fluid is centrifuged towards the periphery of the rotating disc, the fluid becomes charged to the same potential as the segment over which it is passing. Particulate matter is attracted to the charged segment and is captured by the fluid. The fluid then carries the captured particulate matter to a collection device such as a toroidal container disposed around the periphery of the disc. A grounded electrically-conductive ring may be disposed at the outer periphery of the disc to neutralize the captured particles and the fluid before they enter the container.

  2. Stack Monitor Operating Experience Review

    SciTech Connect

    L. C. Cadwallader; S. A. Bruyere

    2009-05-01

    Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative “all modes” failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.

  3. Ion chromatographic separation and quantitation of alkyl methylamines and ethylamines in atmospheric gas and particulate matter using preconcentration and suppressed conductivity detection.

    PubMed

    VandenBoer, T C; Markovic, M Z; Petroff, A; Czar, M F; Borduas, N; Murphy, J G

    2012-08-24

    Two methods based on ion chromatography (IC) were developed for the detection of methyl and ethyl alkyl amines (methylamine (MA), ethylamine (EA), dimethylamine (DMA), diethylamine (DEA), trimethylamine (TMA) and triethylamine (TEA)) and NH(3)/NH(4)(+) in online atmospheric gas-particle and size-resolved particulate samples. The two IC methods were developed to analyze samples collected with an ambient ion monitor (AIM), an online gas-particle collection system, or with a Micro Orifice Uniform Deposit Impactor (MOUDI) for size-resolved particle samples. These methods enable selective and (semi-) quantitative detection of alkyl amines at ambient atmospheric concentrations (pptv and pgm(-3)) in samples where significant interferences can be expected from Na(+) and NH(4)(+), for example marine and rural air masses. Sample pre-concentration using a trace cation column enabled instrumental detection limits on the order of pmol (sub-ng) levels per sample, an improvement of up to 10(2) over current IC methods. Separation was achieved using a methanesulfonic acid gradient elution on Dionex CS12A and CS17 columns. The relative standard deviations in retention times during 3 weeks continuous (hourly) sampling campaigns ranged from 0.1 to 0.5% and 0.2 to 5% for the CS12A and CS17 across a wide dynamic range of atmospheric concentrations. Resolution of inorganic and organic cations is limited to 25min for online samples. Mass-dependent coelution of NH(4)(+)/MA/EA occurred on the CS12A column and DEA/TMA coeluted on both columns. Calibrations of ammonium show a non-linear response across the entire calibration range while all other analytes exhibit high linearity (R(2)=0.984-0.999), except for EA and TEA on the CS12A (R(2)=0.960 and 0.941, respectively). Both methods have high analytical accuracy for the nitrogenous bases ranging from 9.5 to 20% for NH(3) and <5-15% for the amines. Hourly observations of amines at Egbert, ON in October 2010 showed gaseous DMA and TMA+DEA at 1-10pptv in air, while particulate DMA and TMA+DEA were present at 0.5-4ng m(-3). A size-resolved particulate sample collected over 23h was found to contain DMA, TMA+DEA and MEA at 1.78, 8.15 and 0.03ngm(-3) mass loadings, with the amine mass enhanced in particle sizes between 100 and 1000nm. These results highlight a need for very sensitive and selective detection of methyl and ethyl amines in addition to NH(3) in continuous online monitoring strategies. PMID:22784696

  4. Regenerable particulate filter

    DOEpatents

    Stuecker, John N. (Albuquerque, NM); Cesarano, III, Joseph (Albuquerque, NM); Miller, James E. (Albuquerque, NM)

    2009-05-05

    A method of making a three-dimensional lattice structure, such as a filter used to remove particulates from a gas stream, where the physical lattice structure is designed utilizing software simulation from pre-defined mass transfer and flow characteristics and the designed lattice structure is fabricated using a free-form fabrication manufacturing technique, where the periodic lattice structure is comprised of individual geometric elements.

  5. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn C. England; Stephanie Wien; Mingchih O. Chang

    2002-08-01

    This report provides results from the first year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operations. Detailed emission rate and chemical speciation test results for a refinery gas-fired process heater and plans for cogeneration gas turbine tests and pilot-scale tests are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods to compare PM2.5 mass and chemical speciation. Test plans are presented for a gas turbine facility that will be tested in the fourth quarter of 2002. A preliminary approach for pilot-scale tests is presented that will help define design constraints for a new dilution sampler design that is smaller, lighter, and less costly to use.

  6. The development of a cyclonic combustor for high particulate, low caloric value gas produced by a fluidized bed

    E-print Network

    Cardenas, Manuel Moises

    1985-01-01

    for inlet Reynolds number in the range of 4. 5 x 10 to 6. 5 x 10 and equivalence ratio between 0. 7 and 1. 0. The flame length and shape varied greatly at the various operating conditions. High levels of NO/NOx emissions were measured and believed... Static Puel Pressure Cyclone Combustor Dimensionless Pressure Drop Exiting Gas Temperature Manifold Gas Temperature Flame Length Fuel Heating Value Nitrogen Oxide Emissions Percent of Complete Combustion A Comparison of Measured to Calculated Mass...

  7. Polycyclic aromatic hydrocarbons in gas and particulate phases of indoor environments influenced by tobacco smoke: Levels, phase distributions, and health risks

    NASA Astrophysics Data System (ADS)

    Castro, Dionísia; Slezakova, Klara; Delerue-Matos, Cristina; Alvim-Ferraz, Maria da Conceição; Morais, Simone; Pereira, Maria do Carmo

    2011-04-01

    As polycyclic aromatic hydrocarbons (PAHs) have a negative impact on human health due to their mutagenic and/or carcinogenic properties, the objective of this work was to study the influence of tobacco smoke on levels and phase distribution of PAHs and to evaluate the associated health risks. The air samples were collected at two homes; 18 PAHs (the 16 PAHs considered by U.S. EPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) were determined in gas phase and associated with thoracic (PM 10) and respirable (PM 2.5) particles. At home influenced by tobacco smoke the total concentrations of 18 PAHs in air ranged from 28.3 to 106 ng m -3 (mean of 66.7 ± 25.4 ng m -3), ? PAHs being 95% higher than at the non-smoking one where the values ranged from 17.9 to 62.0 ng m -3 (mean of 34.5 ± 16.5 ng m -3). On average 74% and 78% of ? PAHs were present in gas phase at the smoking and non-smoking homes, respectively, demonstrating that adequate assessment of PAHs in air requires evaluation of PAHs in both gas and particulate phases. When influenced by tobacco smoke the health risks values were 3.5-3.6 times higher due to the exposure of PM 10. The values of lifetime lung cancer risks were 4.1 × 10 -3 and 1.7 × 10 -3 for the smoking and non-smoking homes, considerably exceeding the health-based guideline level at both homes also due to the contribution of outdoor traffic emissions. The results showed that evaluation of benzo[a]pyrene alone would probably underestimate the carcinogenic potential of the studied PAH mixtures; in total ten carcinogenic PAHs represented 36% and 32% of the gaseous ? PAHs and in particulate phase they accounted for 75% and 71% of ? PAHs at the smoking and non-smoking homes, respectively.

  8. Co-flow planar SOFC fuel cell stack

    SciTech Connect

    Chung, Brandon W.; Pham, Ai Quoc; Glass, Robert S.

    2004-11-30

    A co-flow planar solid oxide fuel cell stack with an integral, internal manifold and a casing/holder to separately seal the cell. This construction improves sealing and gas flow, and provides for easy manifolding of cell stacks. In addition, the stack construction has the potential for an improved durability and operation with an additional increase in cell efficiency. The co-flow arrangement can be effectively utilized in other electrochemical systems requiring gas-proof separation of gases.

  9. Fifty years of stacking

    NASA Astrophysics Data System (ADS)

    Rashed, Mohamed

    2014-06-01

    Common-Mid-Point (CMP) stacking is a major process to enhance signal-to-noise ratio in seismic data. Since its appearance fifty years ago, CMP stacking has gone through different phases of prosperity and negligence within the geophysical community. During those times, CMP stacking developed from a simple process of averaging into a sophisticated process that involves complicated mathematics and state-of-the-art computation. This article summarizes the basic principles, assumptions, and violations related to the CMP stacking technique, presents a historical overview on the development stages of CMP stacking, and discusses its future potentiality.

  10. Advanced particulate matter control apparatus and methods

    DOEpatents

    Miller, Stanley J. (Grand Forks, ND); Zhuang, Ye (Grand Forks, ND); Almlie, Jay C. (East Grand Forks, MN)

    2012-01-10

    Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.

  11. COMPACT, IN-STACK, THREE SIZE CUT PARTICLE CLASSIFIER

    EPA Science Inventory

    A compact, in-stack, three size cut particle classifier was designed, fabricated and tested. The classifer consists of a two-stage impactor and back-up filter designed to measure the particulate emissions from sources in three size ranges: greater than 3 micrometer, approximately...

  12. Measurement of fine particulate and gas-phase species during the New Year's fireworks 2005 in Mainz, Germany

    Microsoft Academic Search

    Frank Drewnick; Silke S. Hings; Joachim Curtius; Gunter Eerdekens; Jonathan Williams

    2006-01-01

    The chemical composition and chemically resolved size distributions of fine aerosol particles were measured at high time resolution (5min) with a time-of-flight aerosol mass spectrometer (TOF-AMS) during the New Year's 2005 fireworks in Mainz, central Germany. In addition, particle number concentrations and trace gas concentrations were measured using a condensation particle counter (CPC) and a proton transfer reaction mass spectrometer

  13. Effect of operating condition on particulate matter and nitrogen oxides emissions from a heavy-duty direct injection natural gas engine using cooled exhaust gas recirculation

    Microsoft Academic Search

    G P McTaggart-Cowan; S N Rogak; P G Hill; W K Bushe; S R Munshi

    2004-01-01

    Two methods for reducing nitrogen oxides (NOX) emissions from direct injection, compression ignition, heavy-duty engines are exhaust gas recirculation (EGR) and the high-pressure direct injection of natural gas. Tests combining these two techniques were carried out on a single-cylinder research engine (SCRE) based on a modified heavy-duty automotive engine. No attempt was made to optimize the engine's combustion chamber or

  14. Application of an automatic thermal desorption-gas chromatography-mass spectrometry system for the analysis of polycyclic aromatic hydrocarbons in airborne particulate matter.

    PubMed

    Gil-Moltó, J; Varea, M; Galindo, N; Crespo, J

    2009-02-27

    The application of the thermal desorption (TD) method coupled with gas chromatography-mass spectrometry (GC-MS) to the analysis of aerosol organics has been the focus of many studies in recent years. This technique overcomes the main drawbacks of the solvent extraction approach such as the use of large amounts of toxic organic solvents and long and laborious extraction processes. In this work, the application of an automatic TD-GC-MS instrument for the determination of particle-bound polycyclic aromatic hydrocarbons (PAHs) is evaluated. This device offers the advantage of allowing the analysis of either gaseous or particulate organics without any modification. Once the thermal desorption conditions for PAH extraction were optimised, the method was verified on NIST standard reference material (SRM) 1649a urban dust, showing good linearity, reproducibility and accuracy for all target PAHs. The method has been applied to PM10 and PM2.5 samples collected on quartz fibre filters with low volume samplers, demonstrating its capability to quantify PAHs when only a small amount of sample is available. PMID:19150718

  15. Chemical coupling between atmospheric ozone and particulate matter

    Microsoft Academic Search

    Z. Meng; J. H. Seinfeld; D. Dabdub

    1997-01-01

    A major function of ambient particulate matter arises from atmospheric gas-to-particle conversion. Attempts to reduce particulate matter levels require control of the same organic and nitrogen oxide (NOâ) emissions that are precursors to urban and regional ozone formation. Modeling of the gas-aerosol chemical interactions that govern levels of particulate components showed that control of gas-phase organic and NOâ precursors does

  16. Trace gas and particle emissions from open burning of three cereal crop residues: Increase in residue moistness enhances emissions of carbon monoxide, methane, and particulate organic carbon

    NASA Astrophysics Data System (ADS)

    Hayashi, Kentaro; Ono, Keisuke; Kajiura, Masako; Sudo, Shigeto; Yonemura, Seiichiro; Fushimi, Akihiro; Saitoh, Katsumi; Fujitani, Yuji; Tanabe, Kiyoshi

    2014-10-01

    We determined emission factors for open burning of straw of rice, wheat, and barley, as well as rice husks, and we incorporated the effects of moisture content on the emission factors for the straw. A closed system that simulated on-site backfiring of residues on the soil surface under moderate wind conditions was used to measure the gas and particle emissions from open burning of the residues on an upland field. Two moisture content conditions were evaluated: a dry condition (air-dried residues, 11-13% by weight) and a moist condition (20%). When a linear regression model with the initial moisture content of the residue as the explanatory variable showed good correlation between the primary emission data of a substance and the moisture content, the regression model was adopted as a function to give the emission factors. Otherwise, the unmodified primary data were used as the emission factors. The magnitudes of the gas and particle emissions differed among the residue types. For example, carbon monoxide (CO) emissions from straw of rice, wheat, and barley and rice husks burned under the dry condition were 27.2 ± 1.7, 41.8 ± 24.2, 46.9 ± 2.1, and 66.1 g kg-1 dry matter, and emissions of methane (CH4) were 0.75 ± 0.01, 2.01 ± 0.93, 1.47 ± 0.06, and 5.81 g kg-1 dry matter, respectively (n = 2 for straw with the standard deviation; n = 1 for husks). Emissions of carbon-containing gases and particles (e.g., CO, CH4, and particulate organic carbon) were higher under the moist condition than under the dry condition, which suggests that emission factors for open burning should incorporate the effects of moisture content except open burning performed in the dry season or arid zones.

  17. Impact of alternative fuels on emissions characteristics of a gas turbine engine - part 2: volatile and semivolatile particulate matter emissions.

    PubMed

    Williams, Paul I; Allan, James D; Lobo, Prem; Coe, Hugh; Christie, Simon; Wilson, Christopher; Hagen, Donald; Whitefield, Philip; Raper, David; Rye, Lucas

    2012-10-01

    The work characterizes the changes in volatile and semivolatile PM emissions from a gas turbine engine resulting from burning alternative fuels, specifically gas-to-liquid (GTL), coal-to-liquid (CTL), a blend of Jet A-1 and GTL, biodiesel, and diesel, to the standard Jet A-1. The data presented here, compares the mass spectral fingerprints of the different fuels as measured by the Aerodyne high resolution time-of-flight aerosol mass spectrometer. There were three sample points, two at the exhaust exit plane with dilution added at different locations and another probe located 10 m downstream. For emissions measured at the downstream probe when the engine was operating at high power, all fuels produced chemically similar organic PM, dominated by C(x)H(y) fragments, suggesting the presence of long chain alkanes. The second largest contribution came from C(x)H(y)O(z) fragments, possibly from carbonyls or alcohols. For the nondiesel fuels, the highest loadings of organic PM were from the downstream probe at high power. Conversely, the diesel based fuels produced more organic material at low power from one of the exit plane probes. Differences in the composition of the PM for certain fuels were observed as the engine power decreased to idle and the measurements were made closer to the exit plane. PMID:22913312

  18. Impact of alternative fuels on emissions characteristics of a gas turbine engine - part 1: gaseous and particulate matter emissions.

    PubMed

    Lobo, Prem; Rye, Lucas; Williams, Paul I; Christie, Simon; Uryga-Bugajska, Ilona; Wilson, Christopher W; Hagen, Donald E; Whitefield, Philip D; Blakey, Simon; Coe, Hugh; Raper, David; Pourkashanian, Mohamed

    2012-10-01

    Growing concern over emissions from increased airport operations has resulted in a need to assess the impact of aviation related activities on local air quality in and around airports, and to develop strategies to mitigate these effects. One such strategy being investigated is the use of alternative fuels in aircraft engines and auxiliary power units (APUs) as a means to diversify fuel supplies and reduce emissions. This paper summarizes the results of a study to characterize the emissions of an APU, a small gas turbine engine, burning conventional Jet A-1, a fully synthetic jet fuel, and other alternative fuels with varying compositions. Gas phase emissions were measured at the engine exit plane while PM emissions were recorded at the exit plane as well as 10 m downstream of the engine. Five percent reduction in NO(x) emissions and 5-10% reduction in CO emissions were observed for the alternative fuels. Significant reductions in PM emissions at the engine exit plane were achieved with the alternative fuels. However, as the exhaust plume expanded and cooled, organic species were found to condense on the PM. This increase in organic PM elevated the PM mass but had little impact on PM number. PMID:22913288

  19. Continuous particulate monitoring for emission control

    SciTech Connect

    Bock, A.H. (BHA Group, Inc., Kansas City, MO (United States))

    1993-08-01

    An optical continuous particle monitoring system has been developed to overcome common problems associated with emissions monitoring equipment. Opacity monitors generally use a single- or double-pass system to analyze the presence of dust particles in the flue gas stream. The particles scatter and absorb light as it passes through the stack. As the particle content in the gas stream increases due to bag failure or some other problem, the amount of light that is blocked also increases. The opacity monitor compares the amount of lost light energy to the total energy of the light available and translates the signal to percentage of opacity. Opacity monitors are typically installed to meet the requirements set forth by pollution control agencies. Most opacity monitors are designed to meet all of the requirements of the Environmental Protection Agency (EPA) 40 CFR, Part 60, Appendix B, Performance Specification. The new continuous particle monitor (CPM) increases the accuracy of emission monitoring and overcomes typical problems found in conventional emission monitoring devices. The CPM is an optically based, calibratible, continuous dust monitor that uses a microprocessor, transmitter head, and receiver head. When calibrated with an isokinetic sample, a continuous readout of particulate concentration (in mg/m[sup 3]) in the exhaust gas is provided. The system can be used as a filter bag failure system or a long-term emission trend analyzer. Formal testing was conducted to evaluate the effectiveness of the optically based CPM. The monitor was calibrated using particles of a range of compositions, size distributions, and concentrations. The feasibility of using the instrument to measure particle concentration as low as 10 mg/m[sup 3] was examined.

  20. Computational study of Peptide plane stacking with polar and ionizable amino Acid side chains.

    PubMed

    Wang, Yefei; Wang, Jia; Yao, Lishan

    2015-04-01

    Parallel and T-shaped stacking interactions of the peptide plane with polar and ionizable amino acid side chains (including aspartic/glutamic acid, asparagine/glutamine, and arginine) are investigated using the quantum mechanical MP2 and CCSD computational methods. It is found that the electrostatic interaction plays an essential role in determining the optimal stacking configurations for all investigated stacking models. For certain complexes, the dispersion interaction also contributes considerably to stacking. In the gas phase, the stacking interaction of the charged system is stronger than that of the neutral system, and T-shaped stacking is generally more preferred than parallel stacking, with the stacking energy in the range of -4 to -18 kcal/mol. The solvation effect overall weakens stacking, especially for the charged system and the T-shaped stacking configurations. In water, the interaction energies of different stacking models are comparable. PMID:25826573

  1. Interfaces for stack inspection

    Microsoft Academic Search

    Frédéric Besson; Thomas De Grenier De Latour; Thomas P. Jensen

    2005-01-01

    Stack inspection is a mechanism for programming secure applications in the presence of code from various protection domains. Run-time checks of the call stack allow a method to obtain information about the code that (directly or indirectly) invoked it in order to make access control decisions. This mechanism is part of the security architecture of Java and the .NET Common

  2. Short protection device for stack of electrolytic cells

    DOEpatents

    Katz, Murray (Newington, CT); Schroll, Craig R. (West Hartford, CT)

    1985-10-22

    Electrical short protection is provided in an electrolytic cell stack by the combination of a thin, nonporous ceramic shield and a noble metal foil disposed on opposite sides of the sealing medium in a gas manifold gasket. The thin ceramic shield, such as alumina, is placed between the porous gasket and the cell stack face at the margins of the negative end plate to the most negative cells to impede ion current flow. The noble metal foil, for instance gold, is electrically coupled to the negative potential of the stack to collect positive ions at a harmless location away from the stack face. Consequently, corrosion products from the stack structure deposit on the foil rather than on the stack face to eliminate electrical shorting of cells at the negative end of the stack.

  3. Nature and Magnitude of Aromatic Stacking of Nucleic Acid Bases

    SciTech Connect

    Sponer, Jiri; Riley, Kevin E.; Hobza, Pavel

    2008-04-07

    This review summarises recent advances in quantum chemical calculations of base-stacking forces in nucleic acids. We explain in detail the very complex relationship between the gas-phase basestacking energies, as revealed by quantum chemical (QM) calculations, and the highly variable roles of these interactions in nucleic acids. This issue is rarely discussed in quantum chemical and physical chemistry literature. We further extensively discuss methods that are available for basestacking studies, complexity of comparison of stacking calculations with gas phase experiments, balance of forces in stacked complexes of nucleic acid bases, and the relation between QM and force field descriptions. We also review all recent calculations on base-stacking systems, including details analysis of the B-DNA stacking. Specific attention is paid to the highest accuracy QM calculations, to the decomposition of the interactions, and development of dispersion-balanced DFT methods. Future prospects of computational studies of base stacking are discussed.

  4. A REVIEW OF CURRENT METHODS FOR MEASURING PARTICULATE MATTER INCLUDING CONDENSABLES FROM STATIONARY SOURCES

    EPA Science Inventory

    The PM10 ambient air particulate concentration standardhas created a need for updating measurement methods for PM10 emissions (nominally 10 um aerodynamic diameter and smaller) from stationary sources. Condensable emissions can be a significant portion of stack emissions. Further...

  5. Stacked Blocks Tutorial Written by Michael Tonks

    E-print Network

    Stacked Blocks Tutorial For ME 577 Written by Michael Tonks #12;CE/TOL Stacked Blocks TutorialStacked Blocks TutorialStacked Blocks TutorialStacked Blocks Tutorial 2 TABLE OF CONTENTSTABLE OF CONTENTSTABLE:.................................................................................................................15 #12;CE/TOL Stacked Blocks TutorialStacked Blocks TutorialStacked Blocks TutorialStacked Blocks

  6. Particulate technology issues

    SciTech Connect

    Pontius, D.H.; Vann Bush, P.

    1992-12-01

    Advanced systems for power generation based on coal combustion or gasification will require effective particulate control both for protection of equipment in the gas stream and for compliance with environmental regulations. These new classes of systems will require efficient removal of particles from gas streams at high temperature and high pressure. Primary candidates for particulate control are various types of ceramic filter systems; however, the long-term effects of hot gases and fine particles on the structure and filtration effectiveness of potential filter materials require further study. Thermal gradients induced by pulse cleaning are also of concern. Long-term ``patch tests`` will be conducted on ceramic disks of the same materials used in the fabrication of ceramic candles and ceramic crossflow filters. The primary issues to be addressed in these tests are the long-term physical, thermal, and chemical stability of the ceramic materials; long-term pressure drop and filtration characteristics of the ceramic filters; potential for irreversible blinding of filter elements; and long term performance and reliability of auxiliary hardware, such as the tube sheet and pulse cleaning systems. Each long-term patch test will require about 3 to 4 months of nearly continuous operation.

  7. Size Distribution An Gas/particle Partitionig of Particulate Pah and Elements In The Case of The La Defense Road Tunnel Near Paris

    NASA Astrophysics Data System (ADS)

    Quisefit, J.-P.; Garivait, S.; Schwell, M.; Goriaux, M.; Steiner, E.

    The aim of this study is to characterise, in real circulation conditions, the physico- chemistry of the French automotive emissions. Pollutants measured in a road tunnel are not photochemically processed and thus do represent the original emission at its source. Furthermore, the wide distribution of car types encountered in real circula- tion conditions assures representativety of the actual (French) car park. The French automotive emissions are also of particular interest because the proportion of Diesel engines is bigger than in other countries. Particles were sampled in the La Défense Road tunnel using a Dekati 13 stage cascade impactor as well as a total collector with PM10 head. A biphasic collector was used to study the gas/particle partitioning of the PAHs. The concentration of 14 PAHs was determined in each size fraction by using microwave extraction followed by HPLC in connection with a fluorimeter. Par- ticulate concentration of elements (Al,S,Ca,Cl,Pd,Pt,Ce,Rh...) were determined using X-Ray fluorescence. Environmental conditions, such as temperature, pressure, rela- tive humidity, wind speed as well as CO and NOx levels were monitored continuously during the campaign. The results show clearly that light PAHs, such as phenanthrene, acenaphtene or fluorene exhibit a bimodal distribution. They are adsorbed on fine par- ticles (maximum at about 200 nm) as well as on coarse particles (maximum at about 4 micron). In contrast, heavier PAHs, like Benz(a)pyrene or Benzofluoranthene, are found only on fine particles. Due to its elevated vapour pressure, naphtalene is not observed at all in the particulate phase. These results will be discussed in terms of the thermodynamic properties of the compounds and are compared to similar campaigns in other countries.

  8. Emissions of SO2, NOx and particulates from a pipe manufacturing plant and prediction of impact on air quality.

    PubMed

    Bhanarkar, A D; Majumdar, Deepanjan; Nema, P; George, K V

    2010-10-01

    Integrated pipe manufacturing industry is operation intensive and has significant air pollution potential especially when it is equipped with a captive power production facility. Emissions of SO(2), NO(x), and particulate matter (PM) were estimated from the stationary sources in a state-of-the-art pipe manufacturing plant in India. Major air polluting units like blast furnace, ductile iron spun pipe facility, and captive power production facility were selected for stack gas monitoring. Subsequently, ambient air quality modeling was undertaken to predict ground-level concentrations of the selected air pollutants using Industrial Source Complex (ISC 3) model. Emissions of SO(2), NO(x), and particulate matter from the stationary sources in selected facilities ranged from 0.02 to 16.5, 0.03 to 93.3, and 0.09 to 48.3 kg h(-1), respectively. Concentration of SO(2) and NO(x) in stack gas of 1,180-kVA (1 KW = 1.25 kVA) diesel generator exceeded the upper safe limits prescribed by the State Pollution Control Board, while concentrations of the same from all other units were within the prescribed limits. Particulate emission was highest from the barrel grinding operation, where grinding of the manufactured pipes is undertaken for giving the final shape. Particulate emission was also high from dedusting operation where coal dust is handled. Air quality modeling indicated that maximum possible ground-level concentration of PM, SO(2), and NO(x) were to the tune of 13, 3, and 18 microg/m(3), respectively, which are within the prescribed limits for ambient air given by the Central Pollution Control Board. PMID:19888663

  9. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...CFV-EFC-CVS), sample system with heat exchanger connected to a dilution tunnel. The heat exchanger is not required for the CFV-CVS...particulate sample is collected, a heat exchanger is required. (iii) If a...

  10. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...CFV-EFC-CVS), sample system with heat exchanger connected to a dilution tunnel. The heat exchanger is not required for the CFV-CVS...particulate sample is collected, a heat exchanger is required. (iii) If a...

  11. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CFV-EFC-CVS), sample system with heat exchanger connected to a dilution tunnel. The heat exchanger is not required for the CFV-CVS...particulate sample is collected, a heat exchanger is required. (iii) If a...

  12. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...CFV-EFC-CVS), sample system with heat exchanger connected to a dilution tunnel. The heat exchanger is not required for the CFV-CVS...particulate sample is collected, a heat exchanger is required. (iii) If a...

  13. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...CFV-EFC-CVS), sample system with heat exchanger connected to a dilution tunnel. The heat exchanger is not required for the CFV-CVS...particulate sample is collected, a heat exchanger is required. (iii) If a...

  14. Investigation of time-resolved atmospheric conditions and indoor/outdoor particulate matter concentrations in homes with gas and biomass cook stoves in Nogales, Sonora, Mexico.

    PubMed

    Holmes, Heather A; Pardyjak, Eric R

    2014-07-01

    This paper reports findings from a case study designed to investigate indoor and outdoor air quality in homes near the United States-Mexico border During the field study, size-resolved continuous particulate matter (PM) concentrations were measured in six homes, while outdoor PM was simultaneously monitored at the same location in Nogales, Sonora, Mexico, during March 14-30, 2009. The purpose of the experiment was to compare PM in homes using different fuels for cooking, gas versus biomass, and to obtain a spatial distribution of outdoor PM in a region where local sources vary significantly (e.g., highway, border crossing, unpaved roads, industry). Continuous PM data were collected every 6 seconds using a valve switching system to sample indoor and outdoor air at each home location. This paper presents the indoor PM data from each home, including the relationship between indoor and outdoor PM. The meteorological conditions associated with elevated ambient PM events in the region are also discussed. Results indicate that indoor air pollution has a strong dependence on cooking fuel, with gas stoves having hourly averaged median PM3 concentrations in the range of 134 to 157 microg m(-3) and biomass stoves 163 to 504 microg m(-1). Outdoor PM also indicates a large spatial heterogeneity due to the presence of microscale sources and meteorological influences (median PM3: 130 to 770 microg m(-3)). The former is evident in the median and range of daytime PM values (median PM3: 250 microg m(-3), maximum: 9411 microg m(-3)), while the meteorological influences appear to be dominant during nighttime periods (median PM3: 251 microg m(-3), maximum: 10,846 microg m(-3)). The atmospheric stability is quantified for three nighttime temperature inversion episodes, which were associated with an order of magnitude increase in PM10 at the regulatory monitor in Nogales, AZ (maximum increase: 12 to 474 microg m(-3)). Implications: Regulatory air quality standards are based on outdoor ambient air measurements. However, a large fraction of time is typically spent indoors where a variety of activities including cooking, heating, tobacco smoking, and cleaning can lead to elevated PM concentrations. This study investigates the influence of meteorology, outdoor PM, and indoor activities on indoor air pollution (IAP) levels in the United States-Mexico border region. Results indicate that cooking fuel type and meteorology greatly influence the IAP in homes, with biomass fuel use causing the largest increase in PM concentration. PMID:25122950

  15. Analysis of palladium concentrations in airborne particulate matter with reductive co-precipitation, He collision gas, and ID-ICP-Q-MS.

    PubMed

    Alsenz, H; Zereini, F; Wiseman, C L S; Püttmann, W

    2009-11-01

    The concentration of platinum group elements (PGE) in the environment has increased significantly in the last 20 years mainly due to their use as catalysts in automotive catalytic converters. The quantitation of these metals in different environmental compartments is, however, challenging due to their very low concentrations and the presence of interfering matrix constituents when inductively coupled plasma-mass spectrometry (ICP-MS) is used for analysis. Previously, the research focus was on the analysis of platinum (Pt) and rhodium (Rh). However, due to the increasing use of palladium (Pd) in automotive catalytic converters, quantitation of this element in airborne particulate matter (PM) is also needed. Compared to Pt and Rh, measurements of Pd using ICP-MS are plagued by greater molecular interferences arising from elements such as copper (Cu), zinc (Zn) strontium (Sr), yttrium (Y), and zirconium (Zr). The aim of this study was to evaluate the applicability of reductive co-precipitation procedures using both mercury (Hg) and tellurium (Te) for the pre-concentration of Pd from airborne PM. Furthermore, helium (He) was tested as a collision gas for isotope dilution-inductively coupled plasma-quadrupole-mass spectrometry (ID-ICP-Q-MS) to measure Pd in the Hg and Te precipitates. Airborne PM samples (PM10) were collected from Neuglobsow (Brandenburg, north-eastern Germany) and Deuselbach (Rhineland-Palatinate, south-western Germany), considered to represent background levels, and from the city Frankfurt am Main (Hesse, Germany), a high-traffic area. Samples were first digested with aqua regia in a high-pressure asher (HPA) at 320 degrees C and 130 bar prior to the application of reductive co-precipitation procedures. The method was validated with road dust reference material BCR-723 and the CANMET-CCRMP reference material TDB-1 and WPR-1. In airborne PM collected at the background areas Neuglobsow and Deuselbach, Pd was detected with median concentrations values of 0.5 and 0.6 pg/m3, respectively. Much higher median concentration values of 14.8 pg Pd/m3 (detection limit = 0.01 pg Pd/m3) were detected in samples collected in the city of Frankfurt am Main. Results have shown that Hg co-precipitation depletes the concentrations of interfering matrix constituents by at least one order of magnitude more, compared to Te co-precipitation, making it a more effective method for the isolation and pre-enrichment of Pd from airborne PM prior to analysis. The use of a He gas flow of 120 ml/min in the plasma further minimized interferences, particularly those arising from CuAr+, YO+, and ZrO+ during the determination of Pd. The results demonstrate that Hg co-precipitation and the use of He collision gas, in combination with isotope dilution, are highly effective methods for the quantitation of Pd in airborne PM using ICP-MS. PMID:19784830

  16. Water and thermal management for Ballard PEM fuel cell stack

    NASA Astrophysics Data System (ADS)

    Yu, Xiaochen; Zhou, Biao; Sobiesiak, Andrzej

    A water and thermal management model for a Ballard PEM fuel cell stack was developed to investigate its performance. A general calculation methodology was developed to implement this model. Knowing a set of gas feeding conditions (i.e., pressure, temperature, flow rate) and stack physical conditions (i.e., channel geometry, heat transfer coefficients, operating current), the model could provide information regarding the reaction products (i.e., water and heat), stack power, stack temperature, and system efficiency, thereby assisting the designer in achieving the best thermal and water management. Furthermore, if the stack undergoes a perturbation, such as the initial start-up, quick change in current, or a shutdown, the model could predict the dynamic information regarding stack temperature, cell voltage, and power as a function of time.

  17. Stack filter classifiers

    SciTech Connect

    Porter, Reid B [Los Alamos National Laboratory; Hush, Don [Los Alamos National Laboratory

    2009-01-01

    Just as linear models generalize the sample mean and weighted average, weighted order statistic models generalize the sample median and weighted median. This analogy can be continued informally to generalized additive modeels in the case of the mean, and Stack Filters in the case of the median. Both of these model classes have been extensively studied for signal and image processing but it is surprising to find that for pattern classification, their treatment has been significantly one sided. Generalized additive models are now a major tool in pattern classification and many different learning algorithms have been developed to fit model parameters to finite data. However Stack Filters remain largely confined to signal and image processing and learning algorithms for classification are yet to be seen. This paper is a step towards Stack Filter Classifiers and it shows that the approach is interesting from both a theoretical and a practical perspective.

  18. Characterization of flooding and two-phase flow in polymer electrolyte membrane fuel cell stacks

    Microsoft Academic Search

    G. Karimi; F. Jafarpour; X. Li

    2009-01-01

    A partially flooded gas diffusion layer (GDL) model is proposed and solved simultaneously with a stack flow network model to estimate the operating conditions under which water flooding could be initiated in a polymer electrolyte membrane (PEM) fuel cell stack. The models were applied to the cathode side of a stack, which is more sensitive to the inception of GDL

  19. Laser pulse stacking method

    DOEpatents

    Moses, E.I.

    1992-12-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter. 2 figs.

  20. PARTICULATE MATTER RESEARCH 02

    EPA Science Inventory

    2002 PARTICULATE MATTER GPRA Goal 1: Clean Air; Objective 1.1: Ozone, PM, and SO2 NAAQS; Sub-Objective 1.1.5: Particulate Matter Research Description: In July 1997, EPA revised the National Ambient Air Quality Standard (NAAQS) for Particulate Matter (PM), recogniz...

  1. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-01-26

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  2. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-11-08

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  3. Inertia Coin Stack Challenge

    NSDL National Science Digital Library

    2012-07-08

    In this activity, learners experiment with inertia by performing an easy and hands-on investigation with a playing card and a stack of coins. The activity includes an accompanying Mr. O video which explores Newton's First Law of Motion and inertia in greater detail. Suggestions for extra challenge: add more coins, try different cards.

  4. Stacking up the Atmosphere

    NSDL National Science Digital Library

    Betsy Youngman

    In this hands-on activity, participants learn the characteristics of the five layers of the atmosphere and make illustrations to represent them. They roll the drawings and place them in clear plastic cylinders, and then stack the cylinders to make a model column of the atmosphere.

  5. Particulate fuel bed tests

    NASA Astrophysics Data System (ADS)

    Horn, F. L.; Powell, J. R.; Savino, J. M.

    Gas-cooled reactors using packed beds of small-diameter, coated fuel particles have been proposed for compact, high-power systems. To test the thermal-hydraulic performance of the particulate reactor fuel under simulated reactor conditions, a bed of 800-micrometer diameter particles was heated by its electrical resistance current and cooled by flowing helium gas. The specific resistance of the bed composed of pyrocarbon-coated particles was measured at several temperatures, and found to be 0.09 ohm-cm at 1273 K and 0.06 ohm-cm at 1600 K. The maximum bed power density reached was 1500 W/cu cm at 1500 K. The pressure drop followed the packed-bed correlation, typically 100,000 Pa/cm. The various frit materials used to contain the bed were also tested to 2000 K in helium and hydrogen to determine their properties and reactions with the fuel. Rhenium metal, zirconium carbide, and zirconium oxide appeared to be the best candidate materials, while tungsten and tungsten-rhenium lost mass and strength.

  6. Energy Expenditure of Sport Stacking

    ERIC Educational Resources Information Center

    Murray, Steven R.; Udermann, Brian E.; Reineke, David M.; Battista, Rebecca A.

    2009-01-01

    Sport stacking is an activity taught in many physical education programs. The activity, although very popular, has been studied minimally, and the energy expenditure for sport stacking is unknown. Therefore, the purposes of this study were to determine the energy expenditure of sport stacking in elementary school children and to compare that value…

  7. Progress report and technology status development of an EG and G Berthold LB-150 alpha/beta particulate monitor for use on the East Tennessee Technology Park Toxic Substances Control Act Incinerator

    SciTech Connect

    Shor, J.T.; Singh, S.P.N. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.; Gibson, L.V. Jr. [East Tennessee Technology Park, Oak Ridge, TN (United States). ASO Customer Services Div.

    1998-06-01

    The purpose of this project was to modify and evaluate a commercially available EG and G Berthold LB-150 alpha-beta radionuclide particulate monitor for the high-temperature and moisture-saturation conditions of the East Tennessee Technology Park (formerly K-25 Site) Toxic Substances Control Act (TSCA) Incinerator stack. The monitor was originally outfitted for operation at gas temperatures of 150 F on the defunct Los Alamos National Laboratory (LANL) controlled air incinerator, and the objective was to widen its operating envelope. A laboratory apparatus was constructed that simulated the effects of water-saturated air at the TSCA Incinerator stack-gas temperatures, 183 F. An instrumented set of heat exchangers was constructed to then condition the gas so that the radionuclide monitor could be operated without condensation. Data were collected under the conditions of the elevated temperatures and humidities and are reported herein, and design considerations of the apparatus are provided. The heat exchangers and humidification equipment performed as designed, the Mylar film held, and the instrument suffered no ill effects. However, for reasons as yet undetermined, the sensitivity of the radionuclide detection diminishes as the gas temperature is elevated, whether the gas is humidified or not. The manufacturer has had no experience with (a) the operation of the monitor under these conditions and (b) any commercial market that might exist for an instrument that operates under these conditions. The monitor was not installed into the radiologically contaminated environment of the TSCA Incinerator stack pending resolution of this technical issue.

  8. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers § 77.302 Bypass stacks. Thermal dryer systems shall include a bypass stack, relief stack or individual discharge stack provided...

  9. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers § 77.302 Bypass stacks. Thermal dryer systems shall include a bypass stack, relief stack or individual discharge stack provided...

  10. A liquid water management strategy for PEM fuel cell stacks

    E-print Network

    Van Nguyen, Trung; Knobbe, M. W.

    2003-02-25

    for fuel cell stacks consisting of a few cells, can also be used to prevent non-uniform gas distribution [5]. In the serial configuration the gas from the outlet of the first cell is fed to the inlet of the second cell and so on until the last cell... rates, this method was insufficient. Since no other means was readily or economically available, a water displacement method was used. The stack exhaust was connected to a water bottle with an exit submerged in the water to allow the inflow of gas...

  11. Development of internal reforming carbonate fuel cell stack technology

    SciTech Connect

    Farooque, M.

    1990-10-01

    Activities under this contract focused on the development of a coal-fueled carbonate fuel cell system design and the stack technology consistent with the system design. The overall contract effort was divided into three phases. The first phase, completed in January 1988, provided carbonate fuel cell component scale-up from the 1ft{sup 2} size to the commercial 4ft{sup 2} size. The second phase of the program provided the coal-fueled carbonate fuel cell system (CGCFC) conceptual design and carried out initial research and development needs of the CGCFC system. The final phase of the program emphasized stack height scale-up and improvement of stack life. The results of the second and third phases are included in this report. Program activities under Phase 2 and 3 were designed to address several key development areas to prepare the carbonate fuel cell system, particularly the coal-fueled CFC power plant, for commercialization in late 1990's. The issues addressed include: Coal-Gas Related Considerations; Cell and Stack Technology Improvement; Carbonate Fuel Cell Stack Design Development; Stack Tests for Design Verification; Full-Size Stack Design; Test Facility Development; Carbonate Fuel Cell Stack Cost Assessment; and Coal-Fueled Carbonate Fuel Cell System Design. All the major program objectives in each of the topical areas were successfully achieved. This report is organized along the above-mentioned topical areas. Each topical area has been processed separately for inclusion on the data base.

  12. EVALUATION OF CERAMIC FILTERS FOR HIGH-TEMPERATURE/HIGH-PRESSURE FINE PARTICULATE CONTROL

    EPA Science Inventory

    High temperature gas turbines used to generate electric power require gas streams virtually free of particulate matter. Gas streams from high temperature, high pressure coal processes, such as low Btu gasification and pressurized fluidized bed combustion, require considerable par...

  13. Diesel particulate control

    SciTech Connect

    Bertelsen, F.I. (Manufacturers of Emissions Control Association, Washington, DC (US))

    1988-01-01

    Diesel particulates, because of their chemical composition and extremely small size, have raised health and welfare issues. Health experts have expressed concern that they contribute to or aggravate chronic lung diseases such as asthma, bronchitis and emphysema, and there is the lingering issue about the potential cancer risk from exposure to diesel particulate. Diesel particulates impair visibility, soil buildings, contribute to structural damage through corrosion and give off a pungent odor. Diesel trucks, buses and cars together are such a significant and growing source of particulate emissions. Such vehicles emit 30 to 70 times more particulate matter than gasoline vehicles equipped with catalytic converters. Diesel engines currently power the majority of larger trucks and buses. EPA predicted that, if left uncontrolled, diesel particulate from motor vehicles would increase significantly. Diesel particulate emissions from motor vehicles are particularly troublesome because they frequently are emitted directly into the breathing zone where we work and recreate. The U.S. Congress recognized the risks posed by diesel particulate and as part of the 1977 Clean Air Act Amendments established specific, technology-forcing requirements for controlling these emissions. The U.S. Environmental Protection Agency (EPA) in 1980 established particulate standards for automobiles and light trucks and in 1985, heavy trucks and buses. California, concerned that EPA standards would not adequately protect its citizens, adopted its own set of standards for passenger cars and light trucks. This paper discusses emerging technologies proposed to address the problem.

  14. Process for removal of particulates and SO sub 2 from combustion gases

    Microsoft Academic Search

    W. B. Smith; D. V. Giovanni

    1990-01-01

    This patent describes a process for removing pollutants, including particulates and SOâ, from coal fired boiler flue gases. It comprises: electrostatically removing particulates from the flue gas: thereafter reducing the temperature of the flue gas to a temperature approaching the temperature for moisture saturation of the flue gas and being less than 13°F. and thereafter injecting dry calcium based sulfur

  15. CHARACTERIZATION OF STACK EMISSIONS FROM MUNICIPAL REFUSE-TO-ENERGY SYSTEMS

    EPA Science Inventory

    Stack emissions from three municipal refuse-to-energy systems were characterized: refuse-derived fuel (RDF), mass burning (MASS) and modular (MOD). A comprehensive set of measurements was performed at each site to determine the physical and chemical properties of the particulate ...

  16. Remote measurement of power plant smoke stack effluent velocity. Final report

    Microsoft Academic Search

    C. R. Miller; C. M. Sonnenschein

    1975-01-01

    This report describes the successful demonstration of the ability of a CO Laser Doppler Velocimeter (LDV) to measure remotely the velocity of the effluent from a power plant smoke stack. The basis of the technique is that laser radiation backscattered from particulates in the effluent is Doppler shifted infrequency in proportion to the velocity of the effluent. Measurements were made

  17. IN-STACK PLUME OPACITY FROM ELECTROSTATIC PRECIPITATOR/SCRUBBER SYSTEM AT HARRINGTON UNIT 1

    EPA Science Inventory

    The report gives results of theoretical modeling of particulate emission and in-stack plume opacity for the electrostatic precipitator (ESP)/scrubber system at Southwestern Public Service Company's Harrington Unit 1. The theoretical results of an emission rate of 17.8 ng/J and op...

  18. Pitch based foam with particulate

    DOEpatents

    Klett, James W. (Knoxville, TN)

    2001-01-01

    A thermally conductive, pitch based foam composite having a particulate content. The particulate alters the mechanical characteristics of the foam without severely degrading the foam thermal conductivity. The composite is formed by mixing the particulate with pitch prior to foaming.

  19. Particulate Air Pollution: The Particulars

    ERIC Educational Resources Information Center

    Murphy, James E.

    1973-01-01

    Describes some of the causes and consequences of particulate air pollution. Outlines the experimental procedures for measuring the amount of particulate materials that settles from the air and for observing the nature of particulate air pollution. (JR)

  20. Face crack reduction strategy for particulate filters

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2012-01-31

    A system comprises a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion. A control module initiates combustion of PM in the PM filter using a heater and selectively adjusts oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter. A method comprises providing a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion; initiating combustion of PM in the PM filter using a heater; selectively adjusting oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter.

  1. Measurement of heat conduction through stacked screens

    NASA Technical Reports Server (NTRS)

    Lewis, M. A.; Kuriyama, T.; Kuriyama, F.; Radebaugh, R.

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  2. Tensor deep stacking networks.

    PubMed

    Hutchinson, Brian; Deng, Li; Yu, Dong

    2013-08-01

    A novel deep architecture, the tensor deep stacking network (T-DSN), is presented. The T-DSN consists of multiple, stacked blocks, where each block contains a bilinear mapping from two hidden layers to the output layer, using a weight tensor to incorporate higher order statistics of the hidden binary (½0; 1) features. A learning algorithm for the T-DSN’s weight matrices and tensors is developed and described in which the main parameter estimation burden is shifted to a convex subproblem with a closed-form solution. Using an efficient and scalable parallel implementation for CPU clusters, we train sets of T-DSNs in three popular tasks in increasing order of the data size: handwritten digit recognition using MNIST (60k), isolated state/phone classification and continuous phone recognition using TIMIT (1.1 m), and isolated phone classification using WSJ0 (5.2 m). Experimental results in all three tasks demonstrate the effectiveness of the T-DSN and the associated learning methods in a consistent manner. In particular, a sufficient depth of the T-DSN, a symmetry in the two hidden layers structure in each T-DSN block, our model parameter learning algorithm, and a softmax layer on top of T-DSN are shown to have all contributed to the low error rates observed in the experiments for all three tasks. PMID:23267198

  3. Particulate characterization for PFBC filter systems

    SciTech Connect

    Pontius, D.H.

    1993-09-01

    Southern Research Institute is participating, as a subcontractor to Southern Company Services (SCS), in METC`s project to establish a Power Systems Development Facility at Wilsonville, Alabama. This plant will serve as a facility for the development and testing of advanced systems for coal-based power generation. An important part of the program will be to test and evaluate various kinds of particulate control devices and systems for operation at high temperatures and high pressures. The hot gas cleanup technology is a critical factor in achieving the highest levels of energy efficiency in the advanced power systems. In connection with evaluation of particulate control devices to be installed at this facility, SRI has the responsibility for developing methods and equipment to characterize the particulate material suspended in the hot gas streams. Our objectives are to design systems for sampling and monitoring particulate mass loadings and size distributions at appropriate locations in the plant and to develop methods for operating these systems. We will assist SCS in the preparation of test plans for the operation of the plant, and we will participate in carrying out the particulate measurements.

  4. Airborne particulate discriminator

    DOEpatents

    Creek, Kathryn Louise (San Diego, CA); Castro, Alonso (Santa Fe, NM); Gray, Perry Clayton (Los Alamos, NM)

    2009-08-11

    A method and apparatus for rapid and accurate detection and discrimination of biological, radiological, and chemical particles in air. A suspect aerosol of the target particulates is treated with a taggant aerosol of ultrafine particulates. Coagulation of the taggant and target particles causes a change in fluorescent properties of the cloud, providing an indication of the presence of the target.

  5. CONTROLLING EMISSIONS OF PARTICULATES

    EPA Science Inventory

    The report gives a semi-technical overview of the contribution of particulate matter to the overall U.S. air pollution problem. It also discusses contributions of the Particulate Technology Branch of EPA's Industrial Environmental Research Laboratory at Research Triangle Park, N....

  6. SOFC cells and stacks for complex fuels

    SciTech Connect

    Edward M. Sabolsky; Matthew Seabaugh; Katarzyna Sabolsky; Sergio A. Ibanez; Zhimin Zhong

    2007-07-01

    Reformed hydrocarbon and coal (syngas) fuels present an opportunity to integrate solid oxide fuel cells into the existing fuel infrastructure. However, these fuels often contain impurities or additives that may lead to cell degradation through sulfur poisoning or coking. Achieving high performance and sulfur tolerance in SOFCs operating on these fuels would simplify system balance of plant and sequestration of anode tail gas. NexTech Materials, Ltd., has developed a suite of materials and components (cells, seals, interconnects) designed for operation in sulfur-containing syngas fuels. These materials and component technologies have been integrated into an SOFC stack for testing on simulated propane, logistic fuel reformates and coal syngas. Details of the technical approach, cell and stack performance is reported.

  7. Size distribution of metals in particulate matter formed during combustion of residual fuel oil

    SciTech Connect

    Walsh, P. [Pennsylvania State Univ., University Park, PA (United States); Rovesti, W.C. [Electric Power Research Institute, Washington, DC (United States); Freeman, R.F. [Niagara Mohawk Power Corp., Oswego, NY (United States); Olen, K.R.; Washington, K.T.; Patrick, S.T.; Campbell, G.L.; Harper, D.S. [Florida Power & Light Co., West Palm Beach, FL (United States); Teetz, R.D.; Bennett, T.E. [Long Island Lighting Co., Glenwood Landing, NY (United States)] [and others

    1994-08-01

    Between July 1992 and January 1993 three full-scale test programs were performed by Carnot for the Electric Power Research Institute and the Fuel Oil Users` Support (FOUS) Group, as part of a program for development and testing of various stack emissions models. One of the components of the program was determination of the concentrations of individual elements as a function of the size of particles suspended in flue gas. The size distributions of species are important because several aspects of system performance depend upon particulate matter size and composition: (1) the rate of ash deposition in the convection section, and activity of deposits for high temperature corrosion and SO{sub 3} formation, (2) the efficiency of precipitators for collection of individual elements, and (3) scattering of visible light and contribution of particles to stack plume opacity. Size distributions of major ash constituents were measured at the entrance and exit of the dust collectors during each of the field tests. To the authors` knowledge, these are the first reports of such measurements in residual oil-fired utility boilers. The focus, in the present paper, is on the composition of the particles entering the dust collectors.

  8. Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

    SciTech Connect

    Barnett, J. M.; Cullinan, Valerie I.; Barnett, Debra S.; Trang-Le, Truc LT; Bliss, Mary; Greenwood, Lawrence R.; Ballinger, Marcel Y.

    2009-02-17

    Since the mid-1980s, Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as the correction factor for self absorption of activity for particulate radioactive air samples collected from building exhaust for environmental monitoring. This value accounts for activity that cannot be detected by direct counting of alpha and beta particles. Emissions can be degraded or blocked by filter fibers for particles buried in the filter material or by inactive dust particles collected with the radioactive particles. These filters are used for monitoring air emissions from PNNL stacks for radioactive particles. This paper describes an effort to re-evaluate self-absorption effects in particulate radioactive air sample filters (Versapor® 3000, 47 mm diameter) used at PNNL. There were two methods used to characterize the samples. Sixty samples were selected from the archive for acid digestion to compare the radioactivity measured by direct gas-flow proportional counting of filters to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection. Thirty different sample filters were selected for visible light microscopy to evaluate filter loading and particulate characteristics. Mass-loading effects were also considered. Filter ratios were calculated by dividing the initial counts by the post-digestion counts with the expectation that post-digestion counts would be higher because digestion would expose radioactivity embedded in the filter in addition to that on top of the filter. Contrary to expectations, the post digestion readings were almost always lower than initial readings and averaged approximately half the initial readings for both alpha and beta activity. Before and after digestion readings appeared to be related to each other, but with a low coefficient of determination (R^2) value. The ratios had a wide range of values indicating that this method did not provide sufficient precision to quantify self-absorption effects. The microscopy analysis compares different filter loadings and shows that smaller particle sizes (under 10 micron) can readily be seen on the more lightly loaded filters. At higher loadings, however, the particle size is harder to differentiate. This study provides data on actual stack emission samples showing a range of mass loading conditions and visual evidence of particle size and distribution and also presents the difficulties in quantifying self-absorption effects using actual samples.

  9. Zigzag stacks and m-regular linear stacks.

    PubMed

    Chen, William Y C; Guo, Qiang-Hui; Sun, Lisa H; Wang, Jian

    2014-12-01

    The contact map of a protein fold is a graph that represents the patterns of contacts in the fold. It is known that the contact map can be decomposed into stacks and queues. RNA secondary structures are special stacks in which the degree of each vertex is at most one and each arc has length of at least two. Waterman and Smith derived a formula for the number of RNA secondary structures of length n with exactly k arcs. Höner zu Siederdissen et al. developed a folding algorithm for extended RNA secondary structures in which each vertex has maximum degree two. An equation for the generating function of extended RNA secondary structures was obtained by Müller and Nebel by using a context-free grammar approach, which leads to an asymptotic formula. In this article, we consider m-regular linear stacks, where each arc has length at least m and the degree of each vertex is bounded by two. Extended RNA secondary structures are exactly 2-regular linear stacks. For any m ? 2, we obtain an equation for the generating function of the m-regular linear stacks. For given m, we deduce a recurrence relation and an asymptotic formula for the number of m-regular linear stacks on n vertices. To establish the equation, we use the reduction operation of Chen, Deng, and Du to transform an m-regular linear stack to an m-reduced zigzag (or alternating) stack. Then we find an equation for m-reduced zigzag stacks leading to an equation for m-regular linear stacks. PMID:25455155

  10. Particulate carbon and nitrogen determinations in tracer studies: The neglected variables.

    PubMed

    Collos, Yves; Jauzein, Cécile; Hatey, Elise

    2014-12-01

    We address two issues in the determination of particulate carbon and nitrogen in suspended matter of aquatic environments. One is the adsorption of dissolved organic matter on filters, leading to overestimate particulate matter. The second is the material loss during filtration due to fragile algal cells breaking up. Examples from both laboratory cultures and natural samples are presented. We recommend using stacked filters in order to estimate the first and filtering different volumes of water in order to evaluate the second. PMID:25063941

  11. Spherical Torus Center Stack Design

    SciTech Connect

    C. Neumeyer; P. Heitzenroeder; C. Kessel; M. Ono; M. Peng; J. Schmidt; R. Woolley; I. Zatz

    2002-01-18

    The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents center stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next-step ST (NSST) device.

  12. Radiant zone heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  13. Syntheses and characterization of copper(II) carboxylate dimers formed from enantiopure ligands containing a strong ?···? stacking synthon: enantioselective single-crystal to single-crystal gas/solid-mediated transformations.

    PubMed

    Reger, Daniel L; Horger, Jacob J; Debreczeni, Agota; Smith, Mark D

    2011-10-17

    Tri- and tetrafunctional enantiopure ligands have been prepared from 1,8-naphthalic anhydride and the amino acids L-alanine, D-phenylglycine, and L-asparagine to produce (S)-2-(1,8-naphthalimido)propanoic acid (HL(ala)), (R)-2-(1,8-naphthalimido)-2-phenylacetic acid (HL(phg)), and (S)-4-amino-2-(1,8 naphthalimido)-4-oxobutanoic acid (HL(asn)), respectively. Reactions of L(ala)(-) with copper(II) acetate under a variety of solvent conditions has led to the formation and characterization by X-ray crystallography of three similar copper(II) paddlewheel complexes with different axial ligands, [Cu(2)(L(ala))(4)(THF)(2)] (1), [Cu(2)(L(ala))(4)(HL(ala))] (2), and [Cu(2)(L(ala))(4)(py)(THF)] (3). A similar reaction using THF and L(phg)(-) leads to the formation of [Cu(2)(L(phg))(4)(THF)(2)] (4). With the exception of a disordered component in the structure of 4, the naphthalimide groups in all of these compounds are arranged on the same side of the square, central paddlewheel unit, forming what is known as the chiral crown configuration. A variety of ?···? stacking interactions of the 1,8-naphthalimide groups organize all of these complexes into supramolecular structures. The addition of the amide group functionality in the L(asn)(-) ligand leads to the formation of tetrameric [Cu(4)(L(asn))(8)(py)(MeOH)] (5), where reciprocal axial coordination of one of the amide carbonyl oxygen atoms between two dimers leads to the tetramer. Extensive supramolecular interactions in 5, mainly the ?···? stacking interactions of the 1,8-naphthalimide supramolecular synthon, support an open three-dimensional structure containing large pores filled with solvent. When crystals of [Cu(4)(L(asn))(8)(py)(MeOH)] are exposed to (S)-ethyl lactate vapor, the coordinated methanol molecule is replaced by (S)-ethyl lactate, bonding to the copper ion through the carbonyl oxygen, yielding [Cu(4)(L(asn))(8)(py)((S)-ethyl lactate)] (6) without a loss of crystallinity. With the exception of the replacement of the one axial ligand, the molecular structures of 5 and 6 are very similar. In a similar experiment of 5 with vapors of (R)-ethyl lactate, again a change occurs without a loss of crystallinity, but in this case the (R)-ethyl lactate displaces only slightly more than half of the axial methanol molecules forming [Cu(4)(L(asn))(8)(py){((R)-ethyl lactate)(0.58)(MeOH)(0.42)}] (7). Importantly, in 7, the (R)-ethyl lactate coordinates through the hydroxyl group. When crystals of [Cu(4)(L(asn))(8)(py)(MeOH)] are exposed to vapors of racemic ethyl lactate, the coordinated methanol molecule is displaced without a loss of crystallinity exclusively by (S)-ethyl lactate, yielding a new form of the tetramer [Cu(4)(L(asn))(8)(py)((S)-ethyl lactate)], in which the ethyl lactate in the pocket bonds to the copper(II) ion through the carbonyl oxygen as with 6. Exposure of [Cu(4)(L(asn))(8)(py){((R)-ethyl lactate)(0.58)(MeOH)(0.42)}] to racemic ethyl lactate yields a third form of [Cu(4)(L(asn))(8)(py)((S)-ethyl lactate)], where the three forms of [Cu(4)(L(asn))(8)(py)((S)-ethyl lactate)] have differences in the number of ordered (S)-ethyl lactate molecules located in the interstitial sites. These results demonstrate enantioselective bonding to a metal center in the chiral pocket of both 5 and 7 during single-crystal to single-crystal gas/solid-mediated exchange reactions. PMID:21919476

  14. RETORT WATER PARTICULATES

    E-print Network

    2011-01-01

    nickel and calcium were removed, presumably as crystals, during the filtration of waters CS~60, -62 and -63.63, -69, and -70) also have elevated percent particulate values for chromium, selenium and nickel

  15. Seismic qualification of ventilation stack

    SciTech Connect

    Chen, W.W.; Huang, S.N.; Lindquist, M.R.

    1993-10-01

    This paper describes the method to be used to qualify the 105 K ventilation stack at the U.S. Department of Energy`s Hanford Site, near Richland, Washington, under seismic and wind loadings. The stack stands at 175 ft (53.34 m), with a diameter tapering from 22 ft (6.71 m) at the foundation to 12.83 ft (3.91 m) at the top. Although the stack is classified as Safety Class 3 (low hazard), it is treated as a Safety Class 1 (high hazard) component, as failure could damage a Safety Class 1 facility (the irradiated fuel storage basin). The evaluation used U.S. Department of Energy criteria specified in UCRL 15910 (1990). The seismic responses of the stack under earthquake loading were obtained from modal analyses with response spectrum input that used the ANSYS (1989) finite-element computer code. The moments and shear forces from the results of seismic analysis were used to qualify the reinforcement capacity of the stack structure by the ultimate-strength method. The wind forces acting on the stack in both along-wind and crosswind directions were also calculated. Presented are evaluations of the soil bearing pressure, the moment, and the shear capacity of the stack foundation.

  16. Stacking Faults in Cotton Fibers

    NASA Astrophysics Data System (ADS)

    Divakara, S.; Niranjana, A. R.; Siddaraju, G. N.; Somashekar, R.

    2011-07-01

    The stacking faults in different variety of cotton fibers have been quantified using wide-angle X-ray scattering (WAXS) data. Exponential functions for the column length distribution have been used for the determination of microstructural parameters. The crystal imperfection parameters like crystal size , lattice strain (g in %), stacking faults (?d) and twin faults (?) have been determined by profile analysis using Fourier method of Warren. We examined different variety of raw cotton fibers using WAXS techniques. In all these cases we note that, the stacking faults are quite significant in determining the property of cotton fibers.

  17. Inhalation of phosphine gas following a fire associated with fumigation of processed pistachio nuts.

    PubMed

    O'Malley, Michael; Fong, Harvard; Sánchez, Martha E; Roisman, Rachel; Nonato, Yvette; Mehler, Louise

    2013-01-01

    On December 10, 2009, a fumigation stack containing aluminum phosphide became soaked with rain water and caught fire at a pistachio processing plant in Kern County, California. Untrained plant personnel responding to the fire had exposure to pyrolysis by-products, particulates, and extinguisher ingredients. Ten workers taken for medical evaluation had respiratory and nonspecific systemic symptoms consistent with exposure to phosphine gas. Six of the 10 workers had respiratory distress, indicated by chest pain, shortness of breath, elevated respiratory rate, or decreased oxygen saturation. Recommendations are made for the management of similar illnesses and prevention of similar exposures. PMID:23540306

  18. MTCI acoustic agglomeration particulate control

    SciTech Connect

    Chandran, R.R.; Mansour, M.N. [Manufacturing and Technology Conversion International, Inc., Columbia, MD (United States); Scaroni, A.W.; Koopmann, G.H. [Pennsylvania State Univ., University Park, PA (United States); Loth, J.L. [West Virginia Univ., Morgantown, WV (United States)

    1994-10-01

    The overall objective of this project is to demonstrate pulse combination induced acoustic enhancement of coal ash agglomeration and sulfur capture at conditions typical of direct coal-fired turbines and PFBC hot gas cleanup. MTCI has developed an advanced compact pulse combustor island for direct coal-firing in combustion gas turbines. This combustor island comprises a coal-fired pulse combustor, a combined ash agglomeration and sulfur capture chamber (CAASCC), and a hot cyclone. In the MTCI proprietary approach, the pulse combustion-induced high intensity sound waves improve sulfur capture efficiency and ash agglomeration. The resulting agglomerates allow the use of commercial cyclones and achieve very high particulate collection efficiency. In the MTCI proprietary approach, sorbent particles are injected into a gas stream subjected to an intense acoustic field. The acoustic field serves to improve sulfur capture efficiency by enhancing both gas film and intra-particle mass transfer rates. In addition, the sorbent particles act as dynamic filter foci, providing a high density of stagnant agglomerating centers for trapping the finer entrained (in the oscillating flow field) fly ash fractions. A team has been formed with MTCI as the prime contractor and Penn State University and West Virginia University as subcontractors to MTCI. MTCI is focusing on hardware development and system demonstration, PSU is investigating and modeling acoustic agglomeration and sulfur capture, and WVU is studying aerovalve fluid dynamics. Results are presented from all three studies.

  19. HYDRAULIC FRACTURE MODEL SENSITIVITY ANALYSES OF MASSIVELY STACKED LENTICULAR RESERVOIRS

    E-print Network

    HYDRAULIC FRACTURE MODEL SENSITIVITY ANALYSES OF MASSIVELY STACKED LENTICULAR RESERVOIRS that there was an abundant system of micro-scale natural fractures and a less frequent system of macro- scale fractures. In common with most tight gas reservoirs, hydraulic stimulation is required to interconnect the dual

  20. Remote control flare stack igniter for combustible gases

    NASA Technical Reports Server (NTRS)

    Ray, W. L.

    1972-01-01

    Device has been designed and developed for igniting nonrecoverable combustible gases and sustaining combustion of gases evolving from various gas vent stacks. Igniter is superior to existing systems because of simplicity of operation, low cost fabrication, installation, operational and maintainability features, and excellent reliability in all phases of required operations.

  1. Measuring diesel particulate in filters

    SciTech Connect

    Not Available

    1992-06-01

    This paper discusses an on-line soot-load-measurement system, integral part of any diesel particulate filter (DPF) system. Its function is to determine whether either maximum and/or minimum soot load targets have been reached prior to the initiation of the filter regeneration process. There are currently two methods for on-line measurement of soot accumulation in a diesel particulate filter. The first is based on the relationship between DPF back pressure, soot accumulation, and exhaust-gas flow rate. This method requires mapping of the entire engine operating regime to determine the soot load from the pressure data. It also requires transducers capable of such measurements over the full engine operating range. The second method is a more recent innovation based on radio-frequency (RF) technology. Cordierite filters are virtually transparent to RF energy, though soot absorbs it. Thus the decrease in RF signal strength as it passes through a filter can be correlated with the amount of soot present in it. Since the RF-based measurement method is not influenced by exhaust flow rate, it is inherently less complex to calibrate.

  2. 40 CFR 75.16 - Special provisions for monitoring emissions from common, bypass, and multiple stacks for SO2...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...stack. Whenever any portion of the flue gases from an affected unit can be routed...situations (e.g., malfunction of a flue gas desulfurization system), and periods of routine maintenance of the flue gas desulfurization system or...

  3. JV Task 95-Particulate Control Consulting for Minnesota Ore Operations

    SciTech Connect

    Stanley Miller

    2008-10-31

    The purpose of the project was to assist U.S. Steel in the evaluation, selection, planning, design, and testing of potential approaches to help meet U.S. Steel's goal for low-particulate matter emissions and regulatory compliance. The energy-intensive process for producing iron pellets includes treating the pellets in high-temperature kilns in which the iron is converted from magnetite to hematite. The kilns can be fired with either natural gas or a combination of gas and coal or biomass fuel and are equipped with wet venturi scrubbers for particulate control. Particulate measurements at the inlet and outlet of the scrubbers and analysis of size-fractionated particulate samples led to an understanding of the effect of process variables on the measured emissions and an approach to meet regulatory compliance.

  4. Experimental validation of a mathematical model for simulation of SOFC stack performance

    SciTech Connect

    Oedegaard, R. [Statoil R and D, Trondheim (Norway); Karoliussen, H.; Nisancioglu, K. [Norwegian Inst. of Tech., Trondheim (Norway). Dept. of Electrochemistry

    1994-12-31

    A numerical model developed for estimating the temperature, concentration, and current distribution in planar, monolithic SOFC stacks has been used to simulate the performance of a 14-plate, cross flow experimental stack operating with methane as fuel. The numerically-simulated results agree well with the experimental data over a wide range of stack current-voltage characteristics despite uncertainties related to modeling of radiation to the surroundings and the input data for the cell overpotential and methane reforming kinetics. It is shown that, as a result of calibrating the model with experimental results, useful simulations of temperature, current, potential, and gas composition distributions can be carried out for the experimental stack.

  5. Cyclone type air/particulate concentrator and collector

    SciTech Connect

    Haynes, W.R.; Truhan, A.

    1981-01-20

    A cyclone vortex type air cleaner and particulate concentrator is provided having greatly improved air cleaning efficiency as the dirty gas stream is subjected to two distinct skimming operations; one between the gas inlet scroll and the outlet tube and the other at the exit from the gas discharge scroll. The invention may further include means for increasing agglomeration of the particulate by increasing centrifugal separation in an inlet scroll, an outlet scroll and in the outlet tube from the shell or body of the cyclone.

  6. Method for immobilizing particulate materials in a packed bed

    DOEpatents

    Even, Jr., William R. (Livermore, CA); Guthrie, Stephen E. (Livermore, CA); Raber, Thomas N. (Livermore, CA); Wally, Karl (Lafayette, CA); Whinnery, LeRoy L. (Livermore, CA); Zifer, Thomas (Manteca, CA)

    1999-01-01

    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

  7. Method for immobilizing particulate materials in a packed bed

    DOEpatents

    Even, W.R. Jr.; Guthrie, S.E.; Raber, T.N.; Wally, K.; Whinnery, L.L.; Zifer, T.

    1999-02-02

    The present invention pertains generally to immobilizing particulate matter contained in a packed bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that (a) the particulate retains its essential chemical nature, (b) the local movement of the particulate particles is not unduly restricted, (c) bulk powder migration and is prevented, (d) physical and chemical access to the particulate is unchanged over time, and (e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of an individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport. 4 figs.

  8. OVERVIEW OF THE U.S. EPA (ENVIRONMENTAL PROTECTION AGENCY) ELECTROSTATIC PARTICULATE RESEARCH AND DEVELOPMENT PROGRAM

    EPA Science Inventory

    The U.S. EPA's particulate research and development program, divided between an in-house laboratory effort and extramural work at various research institutes, makes use of electrostatics in most of the work associated with stack or ducted emissions. Research facilities which offe...

  9. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Stanley Miller; Rich Gebert; William Swanson

    1999-11-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses. The AHPC is currently being tested at the 2.7-MW scale at the Big Stone power station.

  10. High temperature and pressure particulate flow loop

    Microsoft Academic Search

    Wegrzyn

    1985-01-01

    A 1700°F and 300 psi particulate laden flow loop for flows up to 3000 SCFM has been built at Brookhaven National Laboratory and installed at the Department of Energy's Morgantown Energy Technology Center. The purpose of this test facility is the investigation of multiphase particle\\/gas flow phenomena, high temperature erosion studies, and on-line instrument calibration. The salient features of this

  11. Characterization of cotton gin PM2.5 emissions based on EPA stack sampling methodologies and particle size distributions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A project to characterize cotton gin emissions in terms of stack sampling was conducted during the 2008 through 2011 ginning seasons. The impetus behind the project was the 2006 EPA implementation of a more stringent standard for particulate matter less than or equal to 2.5 µm (PM2.5) and the fact t...

  12. Health Effects of Particulate Matter

    NSDL National Science Digital Library

    Environmental Protection Agency

    This EPA site gives a brief overview of how different sized particulate matter affects human health. It also discusses the environmental impacts of particulate matter, including haze and acid rain. The site also provides links to more in-depth resources about particle pollution and air quality criteria for particulate matter.

  13. Assessment of the 296-S-21 Stack Sampling Probe Location

    SciTech Connect

    Glissmeyer, John A.

    2006-09-08

    Tests were performed to assess the suitability of the location of the air sampling probe on the 296-S-21 stack according to the criteria of ANSI N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. Pacific Northwest National Laboratory conducted most tests on a 3.67:1 scale model of the stack. CH2MHill also performed some limited confirmatory tests on the actual stack. The tests assessed the capability of the air-monitoring probe to extract a sample representative of the effluent stream. The tests were conducted for the practical combinations of operating fans and addressed: (1) Angular Flow--The purpose is to determine whether the velocity vector is aligned with the sampling nozzle. The average yaw angle relative to the nozzle axis should not be more than 20. The measured values ranged from 5 to 11 degrees on the scale model and 10 to 12 degrees on the actual stack. (2) Uniform Air Velocity--The gas momentum across the stack cross section where the sample is extracted should be well mixed or uniform. The uniformity is expressed as the variability of the measurements about the mean, the coefficient of variance (COV). The lower the COV value, the more uniform the velocity. The acceptance criterion is that the COV of the air velocity must be ?20% across the center two-thirds of the area of the stack. At the location simulating the sampling probe, the measured values ranged form 4 to 11%, which are within the criterion. To confirm the validity of the scale model results, air velocity uniformity measurements were made both on the actual stack and on the scale model at the test ports 1.5 stack diameters upstream of the sampling probe. The results ranged from 6 to 8% COV on the actual stack and 10 to 13% COV on the scale model. The average difference for the eight runs was 4.8% COV, which is within the validation criterion. The fact that the scale model results were slightly higher than the actual stack suggests that the other test results on the scale model are conservative relative to the actual stack. (3) Uniform Concentration of Tracer Gases--A uniform contaminant concentration in the sampling plane enables the extraction of samples that represent the true concentration. This was first tested using a tracer gas to represent gaseous effluents. The fan is a good mixer, so injecting the tracer downstream of the fans provides worst-case results. The acceptance criteria are that (1) the COV of the measured tracer gas concentration is ?20% across the center two-thirds of the sampling plane and (2) at no point in the sampling plane does the concentration vary from the mean by >30%. The results on the scale model at the point simulating the sampling probe ranged from 0.3 to 6 %COV, and the maximum single point deviation from the mean was -10%. (4) Uniform Concentration of Tracer Particles--Uniformity in contaminant concentration at the sampling probe was further demonstrated using tracer particles large enough to exhibit inertial effects. Particles of 10-?m aerodynamic diameter were used. The acceptance criterion is that the COV of particle concentration is ?20% across the center two-thirds of the sampling plane. The scale model results ranged form 2 to 9%. Based on these tests, the location of the air sampling probe on the 296-S-21 stack meets the requirements of the ANSI/HPS N13.1-1999 standard.

  14. Studies on the behavior of ammonia and ammonium salts in the atmosphere (1) - Fractional collection of ammonia gas and particulate ammonium

    NASA Technical Reports Server (NTRS)

    Kiin, K.; Fujimura, M.; Hashimoto, Y.

    1981-01-01

    Methods for the fractional collection of trace amounts of atmospheric ammonia gas and ammonium particles on a two staged glass fiber filter are summarized. A standard glass fiber filter washed with distilled water and dried at 120 to 130 C was used. A second filter was impregnated with a mixture of 3% boric acid and 25% glycerin solution. The blank of glass fiber filters impregnated with a mixture of the above solution was very low for ammonia, i.e. 0.06 micrograms in a filter of 47 mm in diameter. The mean concentrations of ammonia and ammonium in air at Kawasaki, a polluted area, were 7.6 and 2.3 micrograms cu m, and those at Sanriku, an unpolluted area 0.9 and 0.2 micrograms cu m, respectively. Ratios of concentration levels of ammonium to total ammonia in the atmosphere were 0.3 and 0.2 for the polluted and unpolluted areas, respectively. Ammonium salts in air at both areas were not correlated with relative humidity. Variations in time of ammonia concentrations and sources in surrounding areas are also considered.

  15. 40 CFR 63.1656 - Performance testing, test methods, and compliance demonstrations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...particulate matter concentration of the stack gas for negative pressure baghouses and positive pressure baghouses with stacks. (6) Method 5D...volumetric flow rate of the stack gas for positive pressure baghouses without stacks. (7) Method...

  16. 40 CFR 63.1656 - Performance testing, test methods, and compliance demonstrations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...particulate matter concentration of the stack gas for negative pressure baghouses and positive pressure baghouses with stacks. (6) Method 5D...volumetric flow rate of the stack gas for positive pressure baghouses without stacks. (7) Method...

  17. 40 CFR 63.1656 - Performance testing, test methods, and compliance demonstrations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...particulate matter concentration of the stack gas for negative pressure baghouses and positive pressure baghouses with stacks. (6) Method 5D...volumetric flow rate of the stack gas for positive pressure baghouses without stacks. (7) Method...

  18. 40 CFR 63.1656 - Performance testing, test methods, and compliance demonstrations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...particulate matter concentration of the stack gas for negative pressure baghouses and positive pressure baghouses with stacks. (6) Method 5D...volumetric flow rate of the stack gas for positive pressure baghouses without stacks. (7) Method...

  19. Seismic attribute for hydrocarbon expressions in stack section

    NASA Astrophysics Data System (ADS)

    Farfour, Mohammed; Yoon, Wang Jung

    2014-12-01

    Stacking process in seismic data processing is a simple and powerful tool commonly used to remove undesired random noise and enhance signal to noise ratio. Basically, the process averages traces from prestack gathers (angles or CDPs) so that they present normal-incidence reflections in stack sections. Experience has showed that hydrocarbons-bearing sediments are generally characterized by anomalous amplitude changes relative to their background from an offset to another. This can result in interesting seismic expressions in the stack section that can help identify reservoirs and delineate their extensions. This paper investigates the conceptual assumptions behind stacking and amplitude variation with offset (AVO). A new attribute is presented and used to detect and extract anomalies associated with hydrocarbon sand reservoirs from their background. The attribute has been examined on real datasets from different fields. The seismic-weighted instantaneous energy attribute showed excellent results in delineating bright spots associated with shallow gas accumulations as well as revealing stratigraphic features of two productive sand-filled channels. Indeed, the paper provides a new insight into seismic stack data analysis and interpretation.

  20. Fine particulate matter (PM) and organic speciation of fireplace emissions

    SciTech Connect

    Purvis, C.R.; McCrillis, R.C.; Kariher, P.H.

    2000-05-01

    This paper presents a summary of fireplace particle size and organic speciation data gathered to date in an ongoing project. Tests are being conducted in a residential wood combustion (RWC) laboratory on three factory-built fireplaces. RWC wood smoke particles <10 {micro}m (PM10) consist primarily of a mixture of organic compounds that have condensed into droplets; therefore, the size distribution and total mass are influenced by temperature of the sample during its collection. During the series 1 tests (15 tests), the dilution tunnel used to cool and dilute the stack gases gave an average mixed gas temperature of 47.3 C and an average dilution ration of 4.3. Averages for the PM2.5 (particles <2.5 {micro}m) and PM10 fractions were 74 and 84%, respectively. For the series 2 tests, the dilution tunnel was modified, reducing the average mixed gas temperatures to 33.8 C and increasing the average dilution ratio to 11.0 in tests completed to date. PM2.5 and PM10 fractions were 83 and 91%, respectively. Since typical winter-time mixed gas temperatures would usually be less than 10 C, these size fraction results probably represent the lower bound; the PM10 and PM2.5 size fraction results might be higher at typical winter temperatures. The particles collected on the first stage were light gray and appeared to include inorganic ash. Particles collected on the remainder of the stages were black and appeared to be condensed organics because there was noticeable lateral bleeding of the collected materials into the filter substrate. Total particulate emission rates ranged from 10.3 to 58.4 g/h; corresponding emission factors ranged from 3.3 to 14.9 g/kg of dry wood burned. A wide range of Environmental Protection Agency (EPA) Method 8270 semivolatile organic compounds were found in the emissions; of the 17 target compounds quantified, major constituents are phenol, 2-methylphenol, 4-methylphenol, 2,4-dimethylphenol, and naphthalene.

  1. Particulate contamination removal from wafers using plasmas and mechanical agitation

    DOEpatents

    Selwyn, G.S.

    1998-12-15

    Particulate contamination removal from wafers is disclosed using plasmas and mechanical agitation. The present invention includes the use of plasmas with mechanical agitation for removing particulate matter from the surface of a wafer. The apparatus hereof comprises a mechanical activator, at least one conducting contact pin for transferring the vibration from the activator to the wafer, clamp fingers that maintain the wafer`s position, and means for generating a plasma in the vicinity of the surface of the wafer, all parts of the cleaning apparatus except the mechanical activator and part of the contact pin being contained inside the processing chamber. By exposing a wafer to a plasma and providing motion thereto in a direction perpendicular to its surface, the bonding between the particulate matter and the surface may be overcome. Once free of the wafer surface, the particulates become charged by electrons from the plasma and are drawn into the plasma by attractive forces which keep them from redepositing. The introduction of a flowing gas through the plasma sweeps the particulates away from the wafer and out of the plasma. The entire surface is cleaned during one cleaning step. The use of an rf plasma to accomplish the particulate removal was found to remove more than 90% of the particulates. 4 figs.

  2. Particulate contamination removal from wafers using plasmas and mechanical agitation

    DOEpatents

    Selwyn, Gary S. (Los Alamos, NM)

    1998-01-01

    Particulate contamination removal from wafers using plasmas and mechanical agitation. The present invention includes the use of plasmas with mechanical agitation for removing particulate matter from the surface of a wafer. The apparatus hereof comprises a mechanical activator, at least one conducting contact pin for transferring the vibration from the activator to the wafer, clamp fingers that maintain the wafer's position, and means for generating a plasma in the vicinity of the surface of the wafer, all parts of the cleaning apparatus except the mechanical activator and part of the contact pin being contained inside the processing chamber. By exposing a wafer to a plasma and providing motion thereto in a direction perpendicular to its surface, the bonding between the particulate matter and the surface may be overcome. Once free of the wafer surface, the particulates become charged by electrons from the plasma and are drawn into the plasma by attractive forces which keep them from redepositing. The introduction of a flowing gas through the plasma sweeps the particulates away from the wafer and out of the plasma. The entire surface is cleaned during one cleaning step. The use of an rf plasma to accomplish the particulate removal was found to remove more than 90% of the particulates.

  3. Respiratory symptoms, lung function and particulate matter pollution in residential indoor environment in Ile-Ife, Nigeria

    PubMed Central

    Ibhafidon, Lawrence I.; Obaseki, Daniel O.; Erhabor, Gregory E.; Akor, Alexander A.; Irabor, Iziegbe; Obioh, IB

    2014-01-01

    Introduction: Particulate air pollution is associated with increased incidence of respiratory symptoms and decreased pulmonary, function but the relative impact of pollution from different domestic energy sources is not well-known or studied. Aim: The study was aimed at assessing the association between particulate concentrations, respiratory symptoms and lung function. Materials and Methods: It was a cross-sectional study comprised of randomly selected residents of three communities. These communities were selected according to the predominant type of fuel used for household cooking which were: firewood, kerosene and liquefied petroleum gas (LPG). Assessment of the indoor PM10 levels was done by filtration using the Gent stacked filter unit sampler for collection of atmospheric aerosol in two size fractions (PM2.5 and PM10). The Medical Research Council (MRC) questionnaire was administered followed by spirometry test. Results: The mean PM10 concentration in participants using LPG, kerosene and firewood was 80.8 ± 9.52 ?g/m3, 236.9 ± 26.5 ?g/m3 and 269 ±93.7 ?g/m3, respectively. The mean age and height-adjusted percent predicted forced expiratory volumes in 1 s (FEV1) for men were 127 ± 7, 109 ± 40 and 91 ± 20 and for women were 129 ± 13, 115 ± 14, 100 ± 14 in users of LPG, kerosene and firewood, respectively. A similar trend was found in the forced vital capacity (FVCs). Users of firewood had significantly lower FEV1 and FVC compared with LPG users (P < 0.05). The participants using firewood had the highest prevalence of pulmonary and non-pulmonary symptoms (57.1%), whereas subjects using LPG had the lowest (23.8%). Conclusion: There are high levels of particulate matter pollutions with respiratory effects in residential indoor environments in Ile-Ife, Nigeria PMID:24970970

  4. Progress Update: Stack Project Complete

    SciTech Connect

    Cody, Tom

    2010-01-01

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  5. Multibeam collimator uses prism stack

    NASA Technical Reports Server (NTRS)

    Minott, P. O.

    1981-01-01

    Optical instrument creates many divergent light beams for surveying and machine element alignment applications. Angles and refractive indices of stack of prisms are selected to divert incoming laser beam by small increments, different for each prism. Angles of emerging beams thus differ by small, precisely-controlled amounts. Instrument is nearly immune to vibration, changes in gravitational force, temperature variations, and mechanical distortion.

  6. Progress Update: Stack Project Complete

    ScienceCinema

    Cody, Tom

    2012-06-14

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  7. Development and Applications of a Stage Stacking Procedure

    NASA Technical Reports Server (NTRS)

    Kulkarni, Sameer; Celestina, Mark L.; Adamczyk, John J.

    2012-01-01

    The preliminary design of multistage axial compressors in gas turbine engines is typically accomplished with mean-line methods. These methods, which rely on empirical correlations, estimate compressor performance well near the design point, but may become less reliable off-design. For land-based applications of gas turbine engines, off-design performance estimates are becoming increasingly important, as turbine plant operators desire peaking or load-following capabilities and hot-day operability. The current work develops a one-dimensional stage stacking procedure, including a newly defined blockage term, which is used to estimate the off-design performance and operability range of a 13-stage axial compressor used in a power generating gas turbine engine. The new blockage term is defined to give mathematical closure on static pressure, and values of blockage are shown to collapse to curves as a function of stage inlet flow coefficient and corrected shaft speed. In addition to these blockage curves, the stage stacking procedure utilizes stage characteristics of ideal work coefficient and adiabatic efficiency. These curves are constructed using flow information extracted from computational fluid dynamics (CFD) simulations of groups of stages within the compressor. Performance estimates resulting from the stage stacking procedure are shown to match the results of CFD simulations of the entire compressor to within 1.6% in overall total pressure ratio and within 0.3 points in overall adiabatic efficiency. Utility of the stage stacking procedure is demonstrated by estimation of the minimum corrected speed which allows stable operation of the compressor. Further utility of the stage stacking procedure is demonstrated with a bleed sensitivity study, which estimates a bleed schedule to expand the compressors operating range.

  8. Manifold seal structure for fuel cell stack

    DOEpatents

    Collins, William P. (South Windsor, CT)

    1988-01-01

    The seal between the sides of a fuel cell stack and the gas manifolds is improved by adding a mechanical interlock between the adhesive sealing strip and the abutting surface of the manifolds. The adhesive is a material which can flow to some extent when under compression, and the mechanical interlock is formed providing small openings in the portion of the manifold which abuts the adhesive strip. When the manifolds are pressed against the adhesive strips, the latter will flow into and through the manifold openings to form buttons or ribs which mechanically interlock with the manifolds. These buttons or ribs increase the bond between the manifolds and adhesive, which previously relied solely on the adhesive nature of the adhesive.

  9. Rigid particulate matter sensor

    DOEpatents

    Hall, Matthew (Austin, TX)

    2011-02-22

    A sensor to detect particulate matter. The sensor includes a first rigid tube, a second rigid tube, a detection surface electrode, and a bias surface electrode. The second rigid tube is mounted substantially parallel to the first rigid tube. The detection surface electrode is disposed on an outer surface of the first rigid tube. The detection surface electrode is disposed to face the second rigid tube. The bias surface electrode is disposed on an outer surface of the second rigid tube. The bias surface electrode is disposed to face the detection surface electrode on the first rigid tube. An air gap exists between the detection surface electrode and the bias surface electrode to allow particulate matter within an exhaust stream to flow between the detection and bias surface electrodes.

  10. Particulate matter dynamics

    E-print Network

    Cionco, Rodolfo G; Caligaris, Marta G

    2012-01-01

    A substantial fraction of the particulate matter released into the atmosphere by industrial or natural processes corresponds to particles whose aerodynamic diameters are greater than 50 mm. It has been shown that, for these particles, the classical description of Gaussian plume diffusion processes, is inadequate to describe the transport and deposition. In this paper we present new results concerning the dispersion of coarse particulate matter. The simulations are done with our own code that uses the Bulirsch Stoer numerical integrator to calculate threedimensional trajectories of particles released into the environment under very general conditions. Turbulent processes are simulated by the Langevin equation and weather conditions are modeled after stable (Monin-Obukhov length L> 0) and unstable conditions (L <0). We present several case studies based on Monte Carlo simulations and discusses the effect of weather on the final deposition of these particles.

  11. Void/particulate detector

    DOEpatents

    Claytor, T.N.; Karplus, H.B.

    1983-09-26

    Apparatus for detecting voids and particulates in a flowing stream of fluid contained in a pipe may comprise: (a) a transducer for transmitting an ultrasonic signal into the stream, coupled to the pipe at a first location; (b) a second transducer for detecting the through-transmission of said signal, coupled to the pipe at a second location; (c) a third transducer for detecting the back-scattering of said signal, coupled to the pipe at a third location, said third location being upstream from said first location; (d) circuit means for normalizing the back-scattered signal from said third transducer to the through-transmitted signal from said second transducer; which normalized signal provides a measure of the voids and particulates flowing past said first location.

  12. Innovations in high-temperature particulate filtration

    SciTech Connect

    Lippert, T. [Westinghouse Science & Technology Center, Pittsburgh, PA (United States)

    1997-05-01

    Fluidized-bed combustion and coal gasification expose sensitive equipment, such as high-speed turbines, to hot combustion offgases. In order to prevent erosion, corrosion, and other damage to sensitive equipment, such systems now incorporate high-temperature particulate filters. One device often considered for such applications uses a design similar to a baghouse (i.e., multiple banks of porous filter bags that remove particulate from gas streams). In this case, however, instead of polyester or teflon fabric, the filter elements are made of rigid ceramic or similar materials. These devices are sometimes called `candle filters,` and the individual ceramic filter elements are frequently called `candles.` Three high-temperature applications of candle filters are described here. 2 refs., 3 figs.

  13. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2012 Fluid and Particulate.zevenhoven@abo.fi 5Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2012 2/84 5.1Overview #12;Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2012 Multi-phase Flow; Two

  14. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham

    2000-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US 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 recollection 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-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

  15. A model for particulate contaminated glow discharges Michael J. t&Caughey and Mark J. Kushner

    E-print Network

    Kushner, Mark

    A model for particulate contaminated glow discharges Michael J. t&Caughey and Mark J. Kushner are often contaminated by particulates resulting from gas phase nucleation or sputtering of surfaces-threshold processes such as ionization may be reduced compared to those in pristine plasmas. If the contamination

  16. CAPSULE REPORT: PARTICULATE CONTROL BY FABRIC FILTRATION ON COAL-FIRED INDUSTRIAL BOILERS

    EPA Science Inventory

    Interest in fabric filtration for boiler particulate control has increased due to the conversion of oil- and gas- to coal-fired boilers and the promulgation of more stringent particulate emission regulations. his report describes the theory, applications, performance, and economi...

  17. Electrostatic precipitator for metal and particulate emission control

    SciTech Connect

    Yang, C.L.; Beltran, M.

    2000-03-01

    Improving air pollution control systems is crucial for incinerators to be an option for sewage sludge disposal. Combinations of venturi and tray tower scrubbers are the most popular air pollution control system for sewage sludge incinerators. Recently wet electrostatic precipitators have been installed downstream of the scrubbing system to ensure the compliance of new regulations. Performance and stack tests were conducted on sludge incinerators at Somerset Raritan Valley Sewage Authority and New England Treatment Company. Efficiencies in terms of heavy metal and particulate removals are presented. This paper also describes sewage sludge incinerators, existing air pollution control systems, design considerations of the wet electrostatic precipitator, as well as sampling and analysis methods.

  18. 40 CFR 86.007-15 - NOX and particulate averaging, trading, and banking for heavy-duty engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Engines, and for 1985 and Later Model Year New Gasoline Fueled, Natural Gas-Fueled, Liquefied Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.007-15 NOX and particulate averaging, trading, and banking for...

  19. MERCURY CONTROL WITH ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller

    2005-05-01

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-00NT40769 and specifically addressed Technical Topical Area 4-Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot Scale. The project team included the Energy & Environmental Research Center (EERC) as the main contractor; W.L. Gore & Associates, Inc., as a technical and financial partner; and the Big Stone Power Plant operated by Otter Tail Power Company, host for the field-testing portion of the research. Since 1995, DOE has supported development of a new concept in particulate control called the advanced hybrid particulate collector (AHPC). The AHPC has been licensed to W.L. Gore & Associates, Inc., and has been marketed as the Advanced Hybrid{trademark} filter by Gore. The Advanced Hybrid{trademark} filter combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The Advanced Hybrid{trademark} filter provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The Advanced Hybrid{trademark} filter also appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas--solid contactor. The objective of the project was to demonstrate 90% total mercury control in the Advanced Hybrid{trademark} filter at a lower cost than current mercury control estimates. The approach included bench-scale batch tests, larger-scale pilot testing with real flue gas on a coal-fired combustion system, and field demonstration at the 2.5-MW (9000-acfm) scale at a utility power plant to prove scale-up and demonstrate longer-term mercury control. An additional task was included in this project to evaluate mercury oxidation upstream of a dry scrubber by using mercury oxidants. This project demonstrated at the pilot-scale level a technology that provides a cost-effective technique to control mercury and, at the same time, greatly enhances fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution for improved fine particulate control combined with effective mercury control for a large segment of the U.S. utility industry as well as other industries.

  20. Space station particulate contamination environment

    NASA Technical Reports Server (NTRS)

    Miller, E. R.; Clifton, K. S.

    1988-01-01

    The origin of particulate contamination on the Space Station will mostly be from pre-launch operations. The adherence and subsequent release of these particles during space flight are discussed. Particle size, release velocity, and release direction are important in determining particle behavior in the vicinity of the vehicle. The particulate environment at the principal science instrument locations is compared to the space shuttle bay environment. Recommendations for possibly decreasing the particulate contamination are presented.

  1. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 Fluid&ParticulateSystems Ã?A424514/2014 Fluid and Particulate systems 424514 /2014 BASIC PRINCIPLES / REVIEW COURSE OVERVIEW Ron Zevenhoven Ã?A Thermal and Flow Engineering ron.zevenhoven@abo.fi 1Fluid&ParticulateSystems 424514

  2. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 Fluid and Particulate and Flow Engineering ron.zevenhoven@abo.fi 4Fluid&ParticulateSystems 424514/2010 Fluid Biskopsgatan 8, FI-20500 Ã?bo / Turku Finland RoNz 2januari 2014 #12;Fluid&ParticulateSystems 424514/2010 Fluid

  3. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems �A424514/2014 Fluid and Particulate" Ron Zevenhoven �A Thermal and Flow Engineering ron.zevenhoven@abo.fi 9Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems �A424514/2014 februari 2014 �bo Akademi University - Värme- och

  4. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems �A424514/2014 Fluid and Particulate Zevenhoven �A Thermal and Flow Engineering ron.zevenhoven@abo.fi 8Fluid&ParticulateSystems 424514/2010 Fluid Strömningsteknik Biskopsgatan 8, FI-20500 �bo / Turku Finland #12;Fluid&ParticulateSystems 424514/2010 Fluid

  5. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems �A424514/2014 Fluid and Particulate Engineering ron.zevenhoven@abo.fi 3Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems �A424514 Strömningsteknik Biskopsgatan 8, FI-20500 �bo / Turku Finland RoNz 2januari 2014 #12;Fluid

  6. PRECISION COSMOGRAPHY WITH STACKED VOIDS

    SciTech Connect

    Lavaux, Guilhem [Department of Physics, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Wandelt, Benjamin D. [UPMC Univ Paris 06, UMR 7095, Institut d'Astrophysique de Paris, 98 bis, boulevard Arago, 75014 Paris (France)

    2012-08-01

    We present a purely geometrical method for probing the expansion history of the universe from the observation of the shape of stacked voids in spectroscopic redshift surveys. Our method is an Alcock-Paczynski (AP) test based on the average sphericity of voids posited on the local isotropy of the universe. It works by comparing the temporal extent of cosmic voids along the line of sight with their angular, spatial extent. We describe the algorithm that we use to detect and stack voids in redshift shells on the light cone and test it on mock light cones produced from N-body simulations. We establish a robust statistical model for estimating the average stretching of voids in redshift space and quantify the contamination by peculiar velocities. Finally, assuming that the void statistics that we derive from N-body simulations is preserved when considering galaxy surveys, we assess the capability of this approach to constrain dark energy parameters. We report this assessment in terms of the figure of merit (FoM) of the dark energy task force and in particular of the proposed Euclid mission which is particularly suited for this technique since it is a spectroscopic survey. The FoM due to stacked voids from the Euclid wide survey may double that of all other dark energy probes derived from Euclid data alone (combined with Planck priors). In particular, voids seem to outperform baryon acoustic oscillations by an order of magnitude. This result is consistent with simple estimates based on mode counting. The AP test based on stacked voids may be a significant addition to the portfolio of major dark energy probes and its potentialities must be studied in detail.

  7. Dust particulate-phonon interaction

    SciTech Connect

    Ishihara, Osamu [Department of Electrical Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409-3102 (United States)

    1998-10-21

    Collective behavior of dust particulates placed in a plasma sheath in the presence of ion acoustic wave is studied. The interaction between dust particulates and ion acoustic wave is treated as a scattering process between dust particulates and phonons (quasi-particles of ion acoustic wave). It is shown that when the streaming of ions becomes supersonic, the system is stable and the ordered structure of plasma crystal is expected to form in the potential of shock-like wake. When the streaming velocity becomes subsonic, the system becomes unstable and the dust particulates are expected to experience phase transition and to show disordered structure.

  8. Airborne Particulate Threat Assessment

    SciTech Connect

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead

    2008-12-31

    Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. government agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our findings and APICD Gen II subsystems for automated collection, deposition and detection of ambient particulate matter. Key findings from the APTA Program include: Ambient biological PM taxonomy; Demonstration of key subsystems needed for autonomous bioaerosol detection; System design; Efficient electrostatic collection; Automated bioagent recognition; Raman analysis performance validating Td<9 sec; Efficient collection surface regeneration; and Development of a quantitative bioaerosol defection model. The objective of the APTA program was to advance the state of our knowledge of ambient background PM composition. Operation of an automated aerosol detection system was enhanced by a more accurate assessment of background variability, especially for sensitive and specific sensing strategies like Raman detection that are background-limited in performance. Based on this improved knowledge of background, the overall threat detection performance of Raman sensors was improved.

  9. Lightweight Stacks of Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  10. Stacks

    ERIC Educational Resources Information Center

    Kimber, Lizzie

    2010-01-01

    Linton Waters and Jayne Kranat ran a session on the Nuffield "Applying Mathematical Processes" (AMP) activities at BCME7 in Manchester in April this year. These 1-2 hour activities are revamps of some of the Graded Assessment in Mathematics (GAIM) resources, developed in the 1980s, and are freely available via the Nuffield website and the original…

  11. A New Approach to Tracing Particulates from Produced Water

    E-print Network

    Taggart, Christopher

    and sink to the bottom, or can coalesce onto microscopic oil droplets and rise to the surface of particulates from oil production platform produced water discharges. Abbreviation MAP magnetically attractive particle 1 Introduction A mixture of oil, gas, and water comes from petroleum reservoirs and is sepa- rated

  12. REGIONAL PARTICULATE MODEL - 1. MODEL DESCRIPTION AND PRELIMINARY RESULTS

    EPA Science Inventory

    The gas-phase chemistry and transport mechanisms of the Regional Acid Deposition Model have been modified to create the Regional Particulate Model, a three-dimensional Eulerian model that simulates the chemistry, transport, and dynamics of sulfuric acid aerosol resulting from pri...

  13. Inductively heated particulate matter filter regeneration control system

    DOEpatents

    Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J

    2012-10-23

    A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.

  14. Toward the Complete Characterization of Atmospheric Organic Particulate Matter: Derivatization and Two-Dimensional Comprehensive Gas Chromatography/Time of Flight Mass Spectrometry as a Method for the Determination of Carboxylic Acids

    NASA Astrophysics Data System (ADS)

    Boris, Alexandra Jeanne

    Understanding the composition of atmospheric organic particulate matter (OPM) is essential for predicting its effects on climate, air quality, and health. However, the polar oxygenated fraction (PO-OPM), which includes a significant mass contribution from carboxylic acids, is difficult to speciate and quantitatively determine by current analytical methods such as gas chromatography-mass spectrometry (GC-MS). The method of chemical derivatization and two-dimensional GC with time of flight MS (GCxGC/TOF-MS) was examined in this study for its efficacy in: 1) quantifying a high percentage of the total organic carbon (TOC) mass of a sample containing PO-OPM; 2) quantitatively determining PO-OPM components including carboxylic acids at atmospherically relevant concentrations; and 3) tentatively identifying PO-OPM components. Two derivatization reagent systems were used in this study: BF3/butanol for the butylation of carboxylic acids, aldehydes, and acidic ketones, and BSTFA for the trimethylsilylation (TMS) of carboxylic acids and alcohols. Three alpha-pinene ozonolysis OPM filter samples and a set of background filter samples were collected by collaborators in a University of California, Riverside environmental chamber. Derivatization/GCxGC TOF-MS was used to tentatively identify some previously unidentified ?-pinene ozonolysis products, and also to show the characteristics of all oxidation products determined. Derivatization efficiencies as measured were 40-70% for most butyl derivatives, and 50-58% for most trimethylsilyl derivatives. A thermal optical method was used to measure the TOC on each filter, and a value of the quantifiable TOC mass using a gas chromatograph was calculated for each sample using GCxGC separation and the mass-sensitive response of a flame ionization detector (FID). The TOC quantified using TMS and GCxGC-FID (TMS/TOCGCxGC FID) accounted for 15-23% of the TOC measured by the thermal-optical method. Using TMS and GCxGC/TOF-MS, 8.85% of the thermal optical TOC was measured and 48.2% of the TMS/TOCGCxGC-FID was semi-quantified using a surrogate standard. The carboxylic acids tentatively identified using TMS and GCxGC/TOF-MS accounted for 8.28% of the TOC measured by thermal optical means. GCxGC TOF-MS chromatograms of derivatized analytes showed reduced peak tailing due in part to the lesser interactions of the derivatized analytes with the stationary phase of the chromatography column as compared to the chromatograms of underivatized samples. The improved peak shape made possible the greater separation, quantification, and identification of high polarity analytes. Limits of detection using derivatization and GCxGC/TOF-MS were <1 ng per ?L injected for a series of C2-C6 di-acids, cis-pinonic acid, and dodecanoic acid using both butylation and TMS. Derivatization with GCxGC/TOF-MS was therefore effective for determining polar oxygenated compounds at low concentrations, for determining specific oxidation products not previously identified in OPM, and also for characterizing the probable functional groups and structures of ?-pinene ozonolysis products.

  15. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 Fluid and Particulate.zevenhoven@abo.fi 2Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 2.1 Flow tube sections-20500 Ã?bo / Turku Finland RoNz 2januari 2014 #12;Fluid&ParticulateSystems 424514/2010 Fluid

  16. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 Fluid and Particulate Engineering ron.zevenhoven@abo.fi 6Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514 8, FI-20500 Ã?bo / Turku Finland RoNz 2januari 2014 #12;Fluid&ParticulateSystems 424514/2010 Fluid

  17. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 10 Fluid Engineering ron.zevenhoven@abo.fi Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514 Ã?bo / Turku Finland RoNz 2/38 #12;Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A

  18. Gas cleaning system and method

    DOEpatents

    Newby, Richard Allen

    2006-06-06

    A gas cleaning system for removing at least a portion of contaminants, such as halides, sulfur, particulates, mercury, and others, from a synthesis gas (syngas). The gas cleaning system may include one or more filter vessels coupled in series for removing halides, particulates, and sulfur from the syngas. The gas cleaning system may be operated by receiving gas at a first temperature and pressure and dropping the temperature of the syngas as the gas flows through the system. The gas cleaning system may be used for an application requiring clean syngas, such as, but not limited to, fuel cell power generation, IGCC power generation, and chemical synthesis.

  19. Apparatus for particulate matter analysis

    DOEpatents

    Gundel, Lara A.; Apte, Michael G.; Hansen, Anthony D.; Black, Douglas R.

    2007-01-30

    The apparatus described herein is a miniaturized system for particle exposure assessment (MSPEA) for the quantitative measurement and qualitative identification of particulate content in gases. The present invention utilizes a quartz crystal microbalance (QCM) or other mass-sensitive temperature compensated acoustic wave resonator for mass measurement. Detectors and probes and light sources are used in combination for the qualitative determination of particulate matter.

  20. Spacecraft particulate sizing spectrometer

    NASA Technical Reports Server (NTRS)

    Miranda, Henry A., Jr.

    1992-01-01

    An evaluation prototype device is described, together with conclusions and several recommendations for follow-on flight hardware. The device detects individual particles crossing an external sensing zone, and produces a histogram displaying the size distribution of particles sensed, over the nominal range of 5 to 50 microns. The output is totally independent of the particle refractive index, and is also largely unaffected by particle shape. The reported diameters are in terms of the equivalent sphere, as judged by the scattered light intercepted by the receiving channels, which develop signals whenever a particle crosses the beam of illumination in the sensing zone. Supporting evidence for the latter assertion is discussed on the basis of experimental test data for non-spherical particulates. Also included is a technical appendix which presents theoretical arguments that provide a firm foundation for this assertion.

  1. Ultra-dark graphene stack metamaterials

    NASA Astrophysics Data System (ADS)

    Chugh, Sunny; Man, Mengren; Chen, Zhihong; Webb, Kevin J.

    2015-02-01

    We present a fabrication method to achieve a graphene stack metamaterial, a periodic array of unit cells composed of graphene and a thin insulating spacer, that allows accumulation of the strong absorption from individual graphene sheets and low reflectivity from the stack. The complex sheet conductivity of graphene from experimental data models the measured power transmitted as a function of wavelength and number of periods in the stack. Simulated results based on the extracted graphene complex sheet conductivity for thicker stacks suggest that the graphene stack reflectivity and the per-unit-length absorption can be controlled to exceed the performance of competing light absorbers. Furthermore, the electrical properties of graphene coupled with the stack absorption characteristics provide for applications in optoelectronic devices.

  2. Hydrogen Embrittlement And Stacking-Fault Energies

    NASA Technical Reports Server (NTRS)

    Parr, R. A.; Johnson, M. H.; Davis, J. H.; Oh, T. K.

    1988-01-01

    Embrittlement in Ni/Cu alloys appears related to stacking-fault porbabilities. Report describes attempt to show a correlation between stacking-fault energy of different Ni/Cu alloys and susceptibility to hydrogen embrittlement. Correlation could lead to more fundamental understanding and method of predicting susceptibility of given Ni/Cu alloy form stacking-fault energies calculated from X-ray diffraction measurements.

  3. Manifold seal for fuel cell stack assembly

    DOEpatents

    Schmitten, Phillip F. (N. Huntingdon, PA); Wright, Maynard K. (Bethel Park, PA)

    1989-01-01

    An assembly for sealing a manifold to a stack of fuel cells includes a first resilient member for providing a first sealing barrier between the manifold and the stack. A second resilient member provides a second sealing barrier between the manifold and the stack. The first and second resilient members are retained in such a manner as to define an area therebetween adapted for retaining a sealing composition.

  4. Particulate distribution function evolution for ejecta transport

    SciTech Connect

    Hammerberg, James Edward [Los Alamos National Laboratory; Plohr, Bradley J [Los Alamos National Laboratory

    2010-01-01

    The time evolution of the ejecta distribution function in a gas is discussed in the context of the recent experiments of W. Buttler and M. Zellner for well characterized Sn surfaces. Evolution equations are derived for the particulate distribution function when the dominant gas-particle interaction in is particulate drag. In the approximation of separability of the distribution function in velocity and size, the solution for the time dependent distribution function is a Fredholm integral equation of the first kind whose kernel is expressible in terms of the vacuum time dependent velocity distribution function measured with piezo probes or Asay foils. The solution of this equation in principle gives the size distribution function. We discuss the solution of this equation and the results of the Buttler - Zellner experiments. These suggest that correlations in velocity and size are necessary for a complete description of the transport dala. The solutions presented also represent an analytic test problem for the calculated distribution function in ejecta transport implementations.

  5. Flexible interconnects for fuel cell stacks

    DOEpatents

    Lenz, David J.; Chung, Brandon W.; Pham, Ai Quoc

    2004-11-09

    An interconnect that facilitates electrical connection and mechanical support with minimal mechanical stress for fuel cell stacks. The interconnects are flexible and provide mechanically robust fuel cell stacks with higher stack performance at lower cost. The flexible interconnects replace the prior rigid rib interconnects with flexible "fingers" or contact pads which will accommodate the imperfect flatness of the ceramic fuel cells. Also, the mechanical stress of stacked fuel cells will be smaller due to the flexibility of the fingers. The interconnects can be one-sided or double-sided.

  6. Micromechanics for particulate reinforced composites

    NASA Technical Reports Server (NTRS)

    Murthy, Pappu L. N.; Goldberg, Robert K.; Mital, Subodh K.

    1996-01-01

    A set of micromechanics equations for the analysis of particulate reinforced composites is developed using the mechanics of materials approach. Simplified equations are used to compute homogenized or equivalent thermal and mechanical properties of particulate reinforced composites in terms of the properties of the constituent materials. The microstress equations are also presented here to decompose the applied stresses on the overall composite to the microstresses in the constituent materials. The properties of a 'generic' particulate composite as well as those of a particle reinforced metal matrix composite are predicted and compared with other theories as well as some experimental data. The micromechanics predictions are in excellent agreement with the measured values.

  7. Scaled Tests and Modeling of Effluent Stack Sampling Location Mixing

    SciTech Connect

    Recknagle, Kurtis P.; Yokuda, Satoru T.; Ballinger, Marcel Y.; Barnett, J. M.

    2009-02-01

    The Pacific Northwest National Laboratory researchers used a computational fluid dynamics (CFD) computer code to evaluate the mixing at a sampling system location of a research and development facility. The facility requires continuous sampling for radioactive air emissions. Researchers sought to determine whether the location would meet the criteria for uniform air velocity and contaminant concentration as prescribed in the American National Standard Institute (ANSI) standard, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. Standard ANSI/HPS N13.1-1999 requires that the sampling location be well-mixed and stipulates specific tests (e.g., velocity, gas, and aerosol uniformity and cyclonic flow angle) to verify the extent of mixing.. The exhaust system for the Radiochemical Processing Laboratory was modeled with a CFD code to better understand the flow and contaminant mixing and to predict mixing test results. The CFD results were compared to actual measurements made at a scale-model stack and to the limited data set for the full-scale facility stack. Results indicated that the CFD code provides reasonably conservative predictions for velocity, gas, and aerosol uniformity. Cyclonic flow predicted by the code is less than that measured by the required methods. In expanding from small to full scale, the CFD predictions for full-scale measurements show similar trends as in the scale model and no unusual effects. This work indicates that a CFD code can be a cost-effective aid in design or retrofit of a facility’s stack sampling location that will be required to meet Standard ANSI/HPS N13.1-1999.

  8. Fluid&ParticulateSystems 424514/2010

    E-print Network

    Zevenhoven, Ron

    Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems Ã?A424514/2014 Fluid&ParticulateSystems Ã?A424514/2014 Fluid and Particulate systems 424514 /2014 LIQUID/SOLID SEPARATIONS Filtration, Sedimentation, Centrifuges Ron Zevenhoven Ã?A Thermal and Flow Engineering ron.zevenhoven@abo.fi 7Fluid

  9. Electrically heated particulate filter restart strategy

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2011-07-12

    A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

  10. Particulate extraction arrangement for automotive turbocharger or the like

    SciTech Connect

    Ishida, N.; Kato, N.; Kawamura, M.

    1988-08-16

    This patent describes an engine system including an exhaust manifold; a turbocharger having a scroll into which exhaust gas from the engine is introduced; a valve for selectively by-passing exhaust gases from the manifold around the scroll into an exhaust conduit; and a particulate separation device operatively interposed between the exhaust manifold, the scroll and the valve, the separation device comprising; a chamber; a first port which establishes fluid communication between the chamber and the manifold; a second port, the second port establishing fluid communication between the chamber and the scroll; and a third port, the third port establishing fluid communication between the chamber and the exhaust conduit via the valve; the chamber including means for inducing particulate matter which is carried thereinto from the manifold through the first port to separate from the exhaust gases and gravitate toward the third port and for inducing particulate matter free exhaust gases to pass through the second port.

  11. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    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 fabric that appeared to be caused by electrical effects. Subsequently, extensive theoretical, bench-scale, and pilot-scale investigations were completed to find an approach to prevent bag damage without compromising AHPC performance. Results showed that the best bag protection and AHPC performance were achieved by using a perforated plate installed between the discharge electrodes and bags. This perforated-plate design was then installed in the 2.5-MW AHPC at Big Stone Power Plant in Big Stone City, South Dakota, and the AHPC was operated from March to June 2001. Results showed that the perforated-plate design solved the bag damage problem and offered even better AHPC performance than the previous design. All of the AHPC performance goals were met, including ultrahigh collection efficiency, high air-to-cloth ratio, reasonable pressure drop, and long bag-cleaning interval.

  12. Stacked graphs--geometry & aesthetics.

    PubMed

    Byron, Lee; Wattenberg, Martin

    2008-01-01

    In February 2008, the New York Times published an unusual chart of box office revenues for 7500 movies over 21 years. The chart was based on a similar visualization, developed by the first author, that displayed trends in music listening. This paper describes the design decisions and algorithms behind these graphics, and discusses the reaction on the Web. We suggest that this type of complex layered graph is effective for displaying large data sets to a mass audience. We provide a mathematical analysis of how this layered graph relates to traditional stacked graphs and to techniques such as ThemeRiver, showing how each method is optimizing a different "energy function". Finally, we discuss techniques for coloring and ordering the layers of such graphs. Throughout the paper, we emphasize the interplay between considerations of aesthetics and legibility. PMID:18988970

  13. Measurement of vehicle particulate emissions.

    PubMed Central

    Beltzer, M

    1975-01-01

    A constant volume sampler (CVS) compatible auto exhaust particulate sampling system has been built which samples exhaust isokinetically at constant temperature. This system yields internally consistent results and is capable of frequent and convenient operation. PMID:50931

  14. A Course in Particulate Processes.

    ERIC Educational Resources Information Center

    Randolph, Alan D.

    1989-01-01

    Provides an overview of a graduate course on particulate processes, especially on crystal size distribution (CSD). Describes the course and includes a list of course topics. Discusses the CSD simulation and manipulation. (YP)

  15. Gas sensor

    DOEpatents

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  16. Electrical diesel particulate filter (DPF) regeneration

    DOEpatents

    Gonze, Eugene V; Ament, Frank

    2013-12-31

    An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

  17. Device for equalizing molten electrolyte content in a fuel cell stack

    DOEpatents

    Smith, J.L.

    1985-12-23

    A device for equalizing the molten electrolyte content throughout the height of a fuel cell stack is disclosed. The device includes a passageway for electrolyte return with electrolyte wettable wicking material in the opposite end portions of the passageway. One end portion is disposed near the upper, negative end of the stack where electrolyte flooding occurs. The second end portion is placed near the lower, positive end of the stack where electrolyte is depleted. Heating means are provided at the upper portion of the passageway to increase electrolyte vapor pressure in the upper wicking material. The vapor is condensed in the lower passageway portion and conducted as molten electrolyte in the lower wick to the positive end face of the stack. An inlet is provided to inject a modifying gas into the passageway and thereby control the rate of electrolyte return.

  18. Device for equalizing molten electrolyte content in a fuel cell stack

    DOEpatents

    Smith, James L. (Lemont, IL)

    1987-01-01

    A device for equalizing the molten electrolyte content throughout the height of a fuel cell stack is disclosed. The device includes a passageway for electrolyte return with electrolyte wettable wicking material in the opposite end portions of the passageway. One end portion is disposed near the upper, negative end of the stack where electrolyte flooding occurs. The second end portion is placed near the lower, positive end of the stack where electrolyte is depleted. Heating means are provided at the upper portion of the passageway to increase electrolyte vapor pressure in the upper wicking material. The vapor is condensed in the lower passageway portion and conducted as molten electrolyte in the lower wick to the positive end face of the stack. An inlet is provided to inject a modifying gas into the passageway and thereby control the rate of electrolyte return.

  19. Stacked optical antennas Dieter W. Pohl,1

    E-print Network

    Novotny, Lukas

    Stacked optical antennas Dieter W. Pohl,1 Sergio G. Rodrigo,2 and Lukas Novotny2,a 1 Institute; published online 13 January 2011 We propose and analyze a stacked optical antenna SOA . It is characterized in microscopy. © 2011 American Institute of Physics. doi:10.1063/1.3541544 Optical antennas are devices

  20. Effective Stack Design in Air Pollution Control.

    ERIC Educational Resources Information Center

    Clarke, John H.

    1968-01-01

    Stack design problems fall into two general caterories--(1) those of building re-entry, and (2) those of general area pollution. Extensive research has developed adequate information, available in the literature, to permit effective stack design. A major roadblock to effective design has been the strong belief by architects and engineers that high…

  1. ESSENTIAL DIMENSION AND ALGEBRAIC STACKS PATRICK BROSNAN

    E-print Network

    that in Definition 1.1 the essential dimension of a depends on the field L. We write ed a instead of ed(a, LESSENTIAL DIMENSION AND ALGEBRAIC STACKS PATRICK BROSNAN , ZINOVY REICHSTEIN , AND ANGELO VISTOLI Abstract. We define and study the essential dimension of an algebraic stack. We compute the essential

  2. Polar stacking of molecules in liquid chloroform.

    PubMed

    Shephard, J J; Soper, A K; Callear, S K; Imberti, S; Evans, J S O; Salzmann, C G

    2015-03-01

    Using neutron diffraction and the isotopic substitution technique we have investigated the local structure of liquid chloroform. A strong tendency for polar stacking of molecules with collinear alignment of dipole moments is found. We speculate that these polar stacks contribute to the performance of chloroform as a solvent. PMID:25562307

  3. Testing of Bluetooth protocol stack using emulator

    Microsoft Academic Search

    Dongxiang Ye; Zhong'ao Jiang; Hong Lin; Qiang Gao

    2001-01-01

    Bluetooth is a promising new technology for short range wireless connectivity between mobile devices. Nevertheless, before the massive products come into the market, reliability of protocol stack and profiles, and interoperability of different Bluetooth products from different vendors are yet to overcome. In this article, we proposed an conformance testing architecture using emulator for different protocol stacks. Our purpose to

  4. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  5. Assaying baseline status of particulate laden polyaromatic hydrocarbon for a grass root level industrial project

    SciTech Connect

    Pandya, G.H.; Chatterjee, N.; Singh, R.; Kashyap, S.; Saheb, S.P.; Wate, S.R. [National Environmental Engineering Research Institute, Nagpur (India)

    2009-02-15

    A study of particulate laden polyaromatic hydrocarbon was conducted at 13 selected locations in a 10 km radial distance of a proposed site for a grass root level industry. Suspended particulate matter samples were continuously monitored for 24 h over a period of 3 months. The Polyaromatic Hydrocarbons (PAHs) were extracted from the particulate samples and analysed using Gas Chromatograph-Mass Spectrometer. Limit of Quantification was also established for individual PAHs. Coal combustion and traffic emission were the major contributors for PAHs in the region. The relative contribution of 2, 3, 4, 5, and 6 ring PAHs in particulates of different sampling sites was also investigated and it is observed that 4 ring (29.76%) and 5 ring (29.06%) compounds are prominent in the particulates measured in the region.

  6. In-situ infrared detection of stack gases

    NASA Astrophysics Data System (ADS)

    Stuart, Derek D.

    1993-03-01

    Infrared measurement using gas-filter correlation (GFC) detection offers an accurate, sensitive, and highly selective technique for the quantitative detection of a number of common industrial gases. A radiative transfer model based on the HITRAN database has been developed to permit the response function of such an instrument to be calculated. The model has been applied to a number of gases, calculating the instrument response to both the target gas and selected interferent species over a broad range of stack temperatures. An optical probe GFC detector has been designed for in-stack measurements of CO and HCl from incinerators and thermal power stations. The probe can be purged with clean air for a true baseline check and a calibration chamber is provided which allows the instrument to be calibrated using bottled gas mixtures. The instrument has completed a successful plant trial during which it measured CO emissions from a coal-fired power station, showing a detection sensitivity of 5 ppm. Detection of HCl has also been demonstrated in the laboratory.

  7. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition

    DOEpatents

    Gonze, Eugene V. (Pinckney, MI); Brown, David B. (Brighton, MI)

    2010-02-02

    A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.

  8. High temperature and pressure particulate flow loop

    SciTech Connect

    Wegrzyn, J.

    1985-04-01

    A 1700/sup 0/F and 300 psi particulate laden flow loop for flows up to 3000 SCFM has been built at Brookhaven National Laboratory and installed at the Department of Energy's Morgantown Energy Technology Center. The purpose of this test facility is the investigation of multiphase particle/gas flow phenomena, high temperature erosion studies, and on-line instrument calibration. The salient features of this flow loop are in its closed loop design, which then permits a low volumetric particle feed rate, in its application of a on-line particle/gas separator and finally in its use of a pneumatic air flow amplifier (eductor). The loop is similar in category to an extrained bed reactor since the feed particles are continuously entrained in the flow and where only a portion of the gas stream is exhausted to maintain a constant pressure level. This presentation discusses the design strategy, the flow and temperature control, as well as the instrumentation that went into the construction of this particle/gas high temperature and pressure test facility.

  9. Mechanisms of accelerated degradation in the front cells of PEMFC stacks and some mitigation strategies

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Pei, Pucheng; He, Yongling; Yuan, Xing; Chao, Pengxiang; Wang, Xizhong

    2013-11-01

    The accelerated degradation in the front cells of a polymer electrolyte membrane fuel cell(PEMFC) stack seriously reduces the reliability and durability of the whole stack. Most researches only focus on the size and configuration of the gas intake manifold, which may lead to the maldistribution of flow and pressure. In order to find out the mechanisms of the accelerated degradation in the front cells, an extensive program of experimental and simulation work is initiated and the results are reported. It is found that after long-term lifetime tests the accelerated degradation in the front cells occurs in all three fuel cell stacks with different flow-fields under the U-type feed configuration. Compared with the rear cells of the stack, the voltage of the front cells is much lower at the same current densities and the membrane electrode assembly(MEA) has smaller active area, more catalyst particle agglomeration and higher ohmic impedance. For further investigation, a series of three dimensional isothermal numerical models are built to investigate the degradation mechanisms based on the experimental data. The simulation results reveal that the dry working condition of the membrane and the effect of high-speed gas scouring the MEA are the main causes of the accelerated degradation in the front cells of a PEM fuel cell stack under the U-type feed configuration. Several mitigation strategies that would mitigate these phenomena are presented: removing cells that have failed and replacing them with those of the same aging condition as the average of the stack; choosing a Z-type feed pattern instead of a U-type one; putting several air flow-field plates without MEA in the front of the stack; or exchanging the gas inlet and outlet alternately at a certain interval. This paper specifies the causes of the accelerated degradation in the front cells and provides the mitigation strategies.

  10. Field measurement of diesel particulate matter emissions.

    PubMed

    Volkwein, Jon C; Mischler, Steven E; Davies, Brian; Ellis, Clive

    2008-03-01

    A primary means to reduce environmental levels of diesel particulate matter (DPM) exposure to miners is to reduce the amount of DPM emission from the engine. A quick and economic method to estimate engine particulate emission levels has been developed. The method relies on the measurement of pressure increase across a filter element that is briefly used to collect a DPM sample directly from the engine exhaust. The method has been refined with the inclusion of an annular aqueous denuder to the tube which permits dry filter samples to be obtained without addition of dilution air. Tailpipe filter samples may then be directly collected in hot and water-supersaturated exhaust gas flows from water bath-cooled coal mine engines without the need for dilution air. Measurement of a differential pressure (DP) increase with time has been related to the mass of elemental carbon (EC) on the filter. Results for laboratory and field measurements of the method showed agreement between DP increase and EC collected on the filter with R(2) values >0.86. The relative standard deviation from replicate samples of DP and EC was 0.16 and 0.11, respectively. The method may also have applications beyond mining, where qualitative evaluation of engine emissions is desirable to determine if engine or control technology maintenance may be required. PMID:18281294

  11. Modeling the Air Flow in the 3410 Building Filtered Exhaust Stack System

    SciTech Connect

    Recknagle, Kurtis P.; Barnett, J. M.; Suffield, Sarah R.

    2013-01-23

    Additional ventilation capacity has been designed for the 3410 Building filtered exhaust stack system. The updated system will increase the number of fans from two to three and will include ductwork to incorporate the new fan into the existing stack. Stack operations will involve running various two-fan combinations at any given time. The air monitoring system of the existing two-fan stack was previously found to be in compliance with the ANSI/HPS N13.1-1999 standard, however it is not known if the modified (three-fan) system will comply. Subsequently, a full-scale three-dimensional (3-D) computational fluid dynamics (CFD) model of the modified stack system has been created to examine the sampling location for compliance with the standard. The CFD modeling results show good agreement with testing data collected from the existing 3410 Building stack and suggest that velocity uniformity and flow angles will remain well within acceptance criteria when the third fan and associated ductwork is installed. This includes two-fan flow rates up to 31,840 cfm for any of the two-fan combinations. For simulation cases in which tracer gas and particles are introduced in the main duct, the model predicts that both particle and tracer gas coefficients of variance (COVs) may be larger than the acceptable 20 percent criterion of the ANSI/HPS N13.1-1999 standard for each of the two-fan, 31,840 cfm combinations. Simulations in which the tracers are introduced near the fans result in improved, though marginally acceptable, COV values for the tracers. Due to the remaining uncertainty that the stack will qualify with the addition of the third fan and high flow rates, a stationary air blender from Blender Products, Inc. is considered for inclusion in the stack system. A model of the air blender has been developed and incorporated into the CFD model. Simulation results from the CFD model that includes the air blender show striking improvements in tracer gas mixing and tracer particle dispersion. The results of these simulations suggest the air blender should be included in the stack system to ensure qualification of the stack.

  12. Evaluation of distributed gas cooling of pressurized PAFC for utility power generation

    NASA Technical Reports Server (NTRS)

    Farooque, M.; Hooper, M.; Maru, H.

    1981-01-01

    A proof-of-concept test for a gas-cooled pressurized phosphoric acid fuel cell is described. After initial feasibility studies in short stacks, two 10 kW stacks are tested. Progress includes: (1) completion of design of the test stations with a recirculating gas cooling loop; (2) atmospheric testing of the baseline stack.

  13. Evaluation of distributed gas cooling of pressurized PAFC for utility power generation

    NASA Astrophysics Data System (ADS)

    Farooque, M.; Hooper, M.; Maru, H.

    1981-03-01

    A proof-of-concept test for a gas-cooled pressurized phosphoric acid fuel cell is described. After initial feasibility studies in short stacks, two 10 kW stacks are tested. Progress includes: (1) completion of design of the test stations with a recirculating gas cooling loop; (2) atmospheric testing of the baseline stack.

  14. Slip stacking experiments at Fermilab main injector

    SciTech Connect

    Kiyomi Koba et al.

    2003-06-02

    In order to achieve an increase in proton intensity, Fermilab Main Injector will use a stacking process called ''slip stacking''. The intensity will be doubled by injecting one train of bunches at a slightly lower energy, another at a slightly higher energy, then bringing them together for the final capture. Beam studies have started for this process and we have already verified that, at least for a low beam intensity, the stacking procedure works as expected. For high intensity operation, development work of the feedback and feedforward systems is under way.

  15. Dynamical stability of slip-stacking particles

    NASA Astrophysics Data System (ADS)

    Eldred, Jeffrey; Zwaska, Robert

    2014-09-01

    We study the stability of particles in slip-stacking configuration, used to nearly double proton beam intensity at Fermilab. We introduce universal area factors to calculate the available phase space area for any set of beam parameters without individual simulation. We find perturbative solutions for stable particle trajectories. We establish Booster beam quality requirements to achieve 97% slip-stacking efficiency. We show that slip-stacking dynamics directly correspond to the driven pendulum and to the system of two standing-wave traps moving with respect to each other.

  16. Particulate emissions from diesel engines: correlation between engine technology and emissions.

    PubMed

    Fiebig, Michael; Wiartalla, Andreas; Holderbaum, Bastian; Kiesow, Sebastian

    2014-01-01

    In the last 30 years, diesel engines have made rapid progress to increased efficiency, environmental protection and comfort for both light- and heavy-duty applications. The technical developments include all issues from fuel to combustion process to exhaust gas aftertreatment. This paper provides a comprehensive summary of the available literature regarding technical developments and their impact on the reduction of pollutant emission. This includes emission legislation, fuel quality, diesel engine- and exhaust gas aftertreatment technologies, as well as particulate composition, with a focus on the mass-related particulate emission of on-road vehicle applications. Diesel engine technologies representative of real-world on-road applications will be highlighted.Internal engine modifications now make it possible to minimize particulate and nitrogen oxide emissions with nearly no reduction in power. Among these modifications are cooled exhaust gas recirculation, optimized injections systems, adapted charging systems and optimized combustion processes with high turbulence. With introduction and optimization of exhaust gas aftertreatment systems, such as the diesel oxidation catalyst and the diesel particulate trap, as well as NOx-reduction systems, pollutant emissions have been significantly decreased. Today, sulfur poisoning of diesel oxidation catalysts is no longer considered a problem due to the low-sulfur fuel used in Europe. In the future, there will be an increased use of bio-fuels, which generally have a positive impact on the particulate emissions and do not increase the particle number emissions.Since the introduction of the EU emissions legislation, all emission limits have been reduced by over 90%. Further steps can be expected in the future. Retrospectively, the particulate emissions of modern diesel engines with respect to quality and quantity cannot be compared with those of older engines. Internal engine modifications lead to a clear reduction of the particulate emissions without a negative impact on the particulate-size distribution towards smaller particles. The residual particles can be trapped in a diesel particulate trap independent of their size or the engine operating mode. The usage of a wall-flow diesel particulate filter leads to an extreme reduction of the emitted particulate mass and number, approaching 100%. A reduced particulate mass emission is always connected to a reduced particle number emission. PMID:24606725

  17. Particulate emissions from diesel engines: correlation between engine technology and emissions

    PubMed Central

    2014-01-01

    In the last 30 years, diesel engines have made rapid progress to increased efficiency, environmental protection and comfort for both light- and heavy-duty applications. The technical developments include all issues from fuel to combustion process to exhaust gas aftertreatment. This paper provides a comprehensive summary of the available literature regarding technical developments and their impact on the reduction of pollutant emission. This includes emission legislation, fuel quality, diesel engine- and exhaust gas aftertreatment technologies, as well as particulate composition, with a focus on the mass-related particulate emission of on-road vehicle applications. Diesel engine technologies representative of real-world on-road applications will be highlighted. Internal engine modifications now make it possible to minimize particulate and nitrogen oxide emissions with nearly no reduction in power. Among these modifications are cooled exhaust gas recirculation, optimized injections systems, adapted charging systems and optimized combustion processes with high turbulence. With introduction and optimization of exhaust gas aftertreatment systems, such as the diesel oxidation catalyst and the diesel particulate trap, as well as NOx-reduction systems, pollutant emissions have been significantly decreased. Today, sulfur poisoning of diesel oxidation catalysts is no longer considered a problem due to the low-sulfur fuel used in Europe. In the future, there will be an increased use of bio-fuels, which generally have a positive impact on the particulate emissions and do not increase the particle number emissions. Since the introduction of the EU emissions legislation, all emission limits have been reduced by over 90%. Further steps can be expected in the future. Retrospectively, the particulate emissions of modern diesel engines with respect to quality and quantity cannot be compared with those of older engines. Internal engine modifications lead to a clear reduction of the particulate emissions without a negative impact on the particulate-size distribution towards smaller particles. The residual particles can be trapped in a diesel particulate trap independent of their size or the engine operating mode. The usage of a wall-flow diesel particulate filter leads to an extreme reduction of the emitted particulate mass and number, approaching 100%. A reduced particulate mass emission is always connected to a reduced particle number emission. PMID:24606725

  18. Gaseous and particulate emission control on industrial solid waste incinerators using wet scrubbers

    Microsoft Academic Search

    J. D. Brady; J. H. Andros

    1983-01-01

    The type of waste which is burned in a solid waste incinerator dictates whether or not secondary air pollution control equipment will be required and the type of air pollution control equipment which must be used. Both gas phase and particulate emissions are produced by these incinerators. The most common emission is HCl gas produced by the combustion of chlorine

  19. Development of a size-fractionating stack sampler for collection of particulate matter

    E-print Network

    Bertch, Russell William

    1983-01-01

    particles is desired. For example, in some centripeter designs particles as small as approx- imately 5 to 8 times the cutpoint size will deposit on the entrance walls of the sampler in unacceptable quantities. These wall losses can agglomerate and become...1ngle-stage centripeter over that required for an inertial impactor, 1t 1s best su1ted for single-stage applications, e. g. the separation of respirable from non-respirable particles. The inertial 1mpactor, which has been designed into compact...

  20. Dry scrubbing: a new concept for removing odor and particulates from kraft recovery furnace stack gases

    Microsoft Academic Search

    Bhatia

    1984-01-01

    In order to meet regulatory standards, existing kraft mills, with direct contact evaporators, have essentially the following three options: installation of a new, larger recovery furnace to replace the existing overloaded furnace; or to build a second recovery furnace to handle the extra load; installation or upgrading of existing weak black and\\/or strong black liquor oxidation system(s); these systems are

  1. The movement of small particulate matter in the early solar system and the formation of satellites

    NASA Technical Reports Server (NTRS)

    Gold, T.

    1974-01-01

    The motions of the abundant small particulate matter in the early solar system are discussed. The effects of gas drag and resonance effects of perturbing forces could have led to accretion and differentiation of the matter. The composition of the moon and the existence of the rings of Saturn can be explained on the basis of the assembly of small particulate matter in satellite orbits around the planets.

  2. Overlap zoned electrically heated particulate filter

    SciTech Connect

    Gonze, Eugene V [Pinckney, MI; Chapman, Mark R [Brighton, MI

    2011-07-19

    A system includes a particulate matter (PM) filter that includes an upstream end for receiving exhaust gas and a downstream end. A zoned heater is arranged spaced from the upstream end and comprises N zones, where N is an integer greater than one, wherein each of the N zones comprises M sub-zones, where M is an integer greater than or equal to one, and wherein the N zones and the M sub-zones are arranged in P layers, where P is an integer greater than one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates non-selected ones of the N zones.

  3. Elemental composition of arctic particulate matter

    NASA Technical Reports Server (NTRS)

    Cahill, T. A.; Eldred, R. A.

    1984-01-01

    Measurements were made of the elemental composition of particulate matter collected in flights in the Arctic in spring 1983 as part of the Arctic Gas and Aerosol Sampling Program (AGASP). Ten samples of size-selected particles were analyzed by four nondestructive techniques at Davis. Concentrations were determined for H, C, N, and O by Forward Alpha Scattering Techniques (FAST) and for elements heavier than fluorine by Particle Induced X-ray Emission (PIXE). Total mass was measured gravimetrically, and optical absorption was measured using the Laser Integrating Plate Method (LIPM). Results of the analyses show dramatic differences in concentrations and elemental ratios from the Alaskan Arctic to the Norwegian Arctic, with indications of wood smoke and sulfuric acid in the arctic atmosphere.

  4. ITP Filter Particulate Decontamination Measurement

    SciTech Connect

    Dworjanyn, L.O. [Westinghouse Savannah River Company, Aiken, SC (United States)

    1993-05-21

    A new test method was developed which showed the installed In- Tank Precipitation Filter Unit {number_sign}3 provided at least 40, 000 x decontamination of the precipitated potassium tetraphenylborate (KTPB) during the cold chemical runs.This filter is expected to meet the needed 40,000 x hot cesium decontamination requirements, assuming that the cesium precipitate, CsTPB, behaves the same as KTPB. The new method permits cold chemicals field testing of installed filters to quantify particulate decontamination and verify filter integrity before going hot. The method involves a 1000 x concentration of fine particulate KTPB in the filtrate to allow direct analysis by counting for naturally radioactive isotope K-40 using the underground SRTC gamma spectroscopy facility. The particulate concentration was accomplished by ultra filtration at Rhone-Poulenc, NJ, using a small cross-flow bench facility, followed by collection of all suspended solids on a small filter disc for K analysis.

  5. Mobile Particulate Emission Studies of New York City Vehicles

    Microsoft Academic Search

    M. Canagaratna; J. Jayne; Q. Shi; C. E. Kolb; D. Worsnop

    2002-01-01

    Emissions from both diesel and gasoline powered motor vehicles are a significant source of urban particulate (PM2.5) and trace gas pollution. Emission characteriza- tions of motor vehicles are typically performed using a dynamometer. Few studies have been performed which characterize emissions from in-use vehicles using a mo- bile sampling platform. This work, which was part of the PM2.5 Technology Assess-

  6. ANGULAR FLOW INSENSITIVE PITOT TUBE SUITABLE FOR USE WITH STANDARD STACK TESTING EQUIPMENT

    EPA Science Inventory

    Five pitot tube designs were tested under various gas flow conditions for accuracy in measuring static and total pressure. The static- and impact-pressure measuring tubes least affected by angular flow were combined and then evaluated in the presence of standard particulate sampl...

  7. Cross-flow, filter-sorbent catalyst for particulate, SO sub 2 and NO sub x control

    SciTech Connect

    Benedek, K. (Little (Arthur D.), Inc., Cambridge, MA (United States)); Flytzani-Stephanopoulos, M. (Massachusetts Inst. of Tech., Cambridge, MA (United States))

    1991-08-01

    This report describes a new concept for integrated pollutant control: a cross-flow filter comprised of layered, gas permeable membranes that act a particulate filter, an SO{sub 2} sorbent, and a NO{sub x} reduction catalyst.

  8. Method and apparatus for transport, introduction, atomization and excitation of emission spectrum for quantitative analysis of high temperature gas sample streams containing vapor and particulates without degradation of sample stream temperature

    DOEpatents

    Eckels, David E. (Ankeny, IA); Hass, William J. (Ames, IA)

    1989-05-30

    A sample transport, sample introduction, and flame excitation system for spectrometric analysis of high temperature gas streams which eliminates degradation of the sample stream by condensation losses.

  9. Influence of the ?–? interaction on the hydrogen bonding capacity of stacked DNA/RNA bases

    PubMed Central

    Mignon, Pierre; Loverix, Stefan; Steyaert, Jan; Geerlings, Paul

    2005-01-01

    The interplay between aromatic stacking and hydrogen bonding in nucleobases has been investigated via high-level quantum chemical calculations. The experimentally observed stacking arrangement between consecutive bases in DNA and RNA/DNA double helices is shown to enhance their hydrogen bonding ability as opposed to gas phase optimized complexes. This phenomenon results from more repulsive electrostatic interactions as is demonstrated in a model system of cytosine stacked offset-parallel with substituted benzenes. Therefore, the H-bonding capacity of the N3 and O2 atoms of cytosine increases linearly with the electrostatic repulsion between the stacked rings. The local hardness, a density functional theory-based reactivity descriptor, appears to be a key index associated with the molecular electrostatic potential (MEP) minima around H-bond accepting atoms, and is inversely proportional to the electrostatic interaction between stacked molecules. Finally, the MEP minima on surfaces around the bases in experimental structures of DNA and RNA–DNA double helices show that their hydrogen bonding capacity increases when taking more neighboring (intra-strand) stacking partners into account. PMID:15788750

  10. Development and demonstration of a higher temperature PEM fuel cell stack

    NASA Astrophysics Data System (ADS)

    Bonville, Leonard J.; Kunz, H. Russell; Song, Ying; Mientek, Anthony; Williams, Minkmas; Ching, Albert; Fenton, James M.

    Research and development was conducted on a proton exchange membrane (PEM) fuel cell stack to demonstrate the capabilities of Ionomem Corporation's composite membrane to operate at 120 °C and ambient pressure for on-site electrical power generation with useful waste heat. The membrane was a composite of polytetrafluoroethylene (PTFE), Nafion ®, and phosphotungstic acid. Studies were first performed on the membrane, cathode catalyst layer, and gas diffusion layer to improve performance in 25 cm 2, subscale cells. This technology was then scaled-up to a commercial 300 cm 2 size and evaluated in multi-cell stacks. The resulting stack obtained a performance near that of the subscale cells, 0.60 V at 400 mA cm -2 at near 120 °C and ambient pressure with hydrogen and air reactants containing water at 35% relative humidity. The water used for cooling the stack resulted in available waste heat at 116 °C. The performance of the stack was verified. This was the first successful test of a higher-temperature, PEM, fuel-cell stack that did not use phosphoric acid electrolyte.

  11. Solid oxide fuel cell generator with removable modular fuel cell stack configurations

    DOEpatents

    Gillett, J.E.; Dederer, J.T.; Zafred, P.R.; Collie, J.C.

    1998-04-21

    A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack. 8 figs.

  12. Solid state marx modulator with blumlein stack for bipolar pulse generation

    Microsoft Academic Search

    J. P. M. Mendes; H. Canacsinh; L. M. Redondo; José O. Rossi

    2011-01-01

    Sub-nanosecond bipolar high voltage pulses are a very important tool for food processing, medical treatment, waste water and exhaust gas processing. A Hybrid Modulator for sub-microsecond bipolar pulse generation, comprising an unipolar solidstate Marx generator connected to a load through a stack Blumlein system that produces bipolar pulses and further multiplies the pulse voltage amplitude, is presented. Experimental results from

  13. THE EFFECTS OF A SQUAT BUILDING ON SHORT STACK EFFLUENTS: A WIND TUNNEL STUDY

    EPA Science Inventory

    In a wind tunnel study, the influence of the highly turbulent region found in the lee of a model building upon plumes emitted from short stacks was examined through smoke visualization and tracer gas concentration mappings. The study was conducted in the Meteorological Wind Tunne...

  14. Stacked vapor fed amtec modules

    DOEpatents

    Sievers, Robert K. (North Huntingdon, PA)

    1989-01-01

    The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

  15. Framed sheaves on projective stacks

    E-print Network

    Ugo Bruzzo; Francesco Sala

    2014-11-05

    Given a normal projective irreducible stack $\\mathscr X$ over an algebraically closed field of characteristic zero we consider framed sheaves on $\\mathscr X$, i.e., pairs $(\\mathcal E,\\phi_{\\mathcal E})$, where $\\mathcal E$ is a coherent sheaf on $\\mathscr X$ and $\\phi_{\\mathcal E}$ is a morphism from $\\mathcal E$ to a fixed coherent sheaf $\\mathcal F$. After introducing a suitable notion of (semi)stability, we construct a projective scheme, which is a moduli space for semistable framed sheaves with fixed Hilbert polynomial, and an open subset of it, which is a fine moduli space for stable framed sheaves. If $\\mathscr X$ is a projective irreducible orbifold of dimension two and $\\mathcal F$ a locally free sheaf on a smooth divisor $\\mathscr D\\subset \\mathscr X$ satisfying certain conditions, we consider $(\\mathscr{D}, \\mathcal{F})$-framed sheaves, i.e., framed sheaves $(\\mathcal E,\\phi_{\\mathcal E})$ with $\\mathcal E$ a torsion-free sheaf which is locally free in a neighborhood of $\\mathscr D$, and ${\\phi_{\\mathcal{E}}}_{| \\mathscr{D}}$ an isomorphism. These pairs are $\\mu$-stable for a suitable choice of a parameter entering the (semi)stability condition, and of the polarization of $\\mathscr X$. This implies the existence of a fine moduli space parameterizing isomorphism classes of $(\\mathscr{D}, \\mathcal{F})$-framed sheaves on $\\mathscr{X}$ with fixed Hilbert polynomial, which is a quasi-projective scheme. In an appendix we develop the example of stacky Hirzebruch surfaces. This is the first paper of a project aimed to provide an algebro-geometric approach to the study of gauge theories on a wide class of 4-dimensional Riemannian manifolds by means of framed sheaves on "stacky" compactifications of them. In particular, in a subsequent paper we will use these results to study gauge theories on ALE spaces of type $A_k$.

  16. SHEAVES ON ALGEBRAIC STACKS 1. Introduction 1

    E-print Network

    de Jong, A. Johan

    4 5. Computing pushforward 6 6. The structure sheaf 8 7. Sheaves of modules 9 8. Representable, it is a problematic beast, because it turns out that a morphism of algebraic stacks does not induce a morphism

  17. Ferromagnetism in ABC-stacked trilayer graphene

    NASA Astrophysics Data System (ADS)

    Olsen, Richard; van Gelderen, Ralph; Smith, C. Morais

    2013-03-01

    In this article we study the ferromagnetic behavior of ABC-stacked trilayer graphene. This is done using a nearest-neighbor tight-binding model, in the presence of long-range Coulomb interactions. For a given electron-electron interaction g and doping level n, we determine whether the total energy is minimized for a paramagnetic or ferromagnetic configuration of our variational parameters. The g versus n phase diagram is first calculated for the unscreened case. We then include the effects of screening using a simplified expression for the fermion bubble diagram. We show that ferromagnetism in ABC-stacked trilayer graphene is more robust than in monolayer, in bilayer, and in ABA-stacked trilayer graphene. Although the screening reduces the ferromagnetic regime in ABC-stacked trilayer graphene, the critical doping level remains one order of magnitude larger than in unscreened bilayer graphene.

  18. StackOverview 2.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

    E-print Network

    Tanaka, Jiro

    17 Web #12;Web Web 81% Web Web Web Web StackOverview #12;1 1 2 Web 3 2.2.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Web . . . . . . . . . . . . . . . . . . . . . . 4 . . . . . . . . . . . . . . . . . . . . . . . . 5 3 Web 6 3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3

  19. Beam loading compensation for slip stacking

    SciTech Connect

    James Steimel; Tim Berenc; Claudio Rivetta

    2003-06-04

    This paper discusses the beam loading compensation requirements to make slip stacking practical in the Fermilab main injector. It also discusses some of the current plans for meeting these requirements with a digital, direct RF feedback system.

  20. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack sampling. (a) Unless a waiver...Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30 days after the...

  1. Wearable solar cells by stacking textile electrodes.

    PubMed

    Pan, Shaowu; Yang, Zhibin; Chen, Peining; Deng, Jue; Li, Houpu; Peng, Huisheng

    2014-06-10

    A new and general method to produce flexible, wearable dye-sensitized solar cell (DSC) textiles by the stacking of two textile electrodes has been developed. A metal-textile electrode that was made from micrometer-sized metal wires was used as a working electrode, while the textile counter electrode was woven from highly aligned carbon nanotube fibers with high mechanical strengths and electrical conductivities. The resulting DSC textile exhibited a high energy conversion efficiency that was well maintained under bending. Compared with the woven DSC textiles that are based on wire-shaped devices, this stacked DSC textile unexpectedly exhibited a unique deformation from a rectangle to a parallelogram, which is highly desired in portable electronics. This lightweight and wearable stacked DSC textile is superior to conventional planar DSCs because the energy conversion efficiency of the stacked DSC textile was independent of the angle of incident light. PMID:24789065

  2. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...subjected to a stacking test. (b) Number of test samples. Three test...packagings constructed of stainless steel, monel, or nickel, only one...required. Exceptions for the number of aluminum and steel sample packagings used...

  3. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless...61.13, each owner or operator processing mercury ore shall test emissions from the source...

  4. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless...61.13, each owner or operator processing mercury ore shall test emissions from the source...

  5. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless...61.13, each owner or operator processing mercury ore shall test emissions from the source...

  6. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless...61.13, each owner or operator processing mercury ore shall test emissions from the source...

  7. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless...61.13, each owner or operator processing mercury ore shall test emissions from the source...

  8. Stacking for Cosmic Magnetism with SKA Surveys

    E-print Network

    Stil, J M

    2015-01-01

    Stacking polarized radio emission in SKA surveys provides statistical information on large samples that is not accessible otherwise due to limitations in sensitivity, source statistics in small fields, and averaging over frequency (including Faraday synthesis). Polarization is a special case because one obvious source of stacking targets is the Stokes I source catalog, possibly in combination with external catalogs, for example an SKA HI survey or a non-radio survey. We point out the significance of stacking sub-samples selected by additional observable parameters to investigate relations that reveal more about the physics of the source. Applications of stacking polarization include, but are not limited to, obtaining in a statistical sense polarization information to the detection limit in total intensity, depolarization as a function of cosmic time at consistent source-frame wavelengths, magnetic field properties in objects with a low radio luminosity such as dwarf and low-surface-brightness galaxies, and in...

  9. 40 CFR 61.44 - Stack sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling...after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given site. All...

  10. 40 CFR 61.44 - Stack sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling...after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given site. All...

  11. 40 CFR 61.44 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling...after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given site. All...

  12. 40 CFR 61.44 - Stack sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling...after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given site. All...

  13. 40 CFR 61.44 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling...after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given site. All...

  14. High strength particulate ceramics

    DOEpatents

    Liles, Kenneth J. (Tuscaloosa, AL); Hoyer, Jesse L. (Tuscaloosa, AL); Mlynarski, Kenneth W. (Gambrills, MD)

    1991-01-01

    This invention relates to new and useful hard, dense, composite materials made from metallic nitrides such as titanium nitride when combined with aluminum oxide and aluminum nitride and a process comprising the steps of: (1) mixing constituent materials using kerosene as a mixing medium; (2) screening, settling, filtering, and washing the mixture in acetone; (3) filling and sealing said materials in a latex mold; (4) isostatically pressing the material into a compacted powder; and (5) sintering the compacted powder in a gas atmosphere at 1,850.degree. C. for two hours.

  15. Modifying Char Dustcake Pressure Drop Using Particulate Additives

    SciTech Connect

    Landham, C.; Dahlin, R.S.; Martin, R.A.; Guan, X.

    2002-09-19

    Coal gasification produces residual particles of coal char, coal ash, and sorbent that are suspended in the fuel gas stream exiting the gasifier. In most cases, these particles (referred to, hereafter, simply as char) must be removed from the stream prior to sending the gas to a turbine, fuel cell, or other downstream device. Currently, the most common approach to cleaning the gas stream at high temperature and pressure is by filtering the particulate with a porous ceramic or metal filter. However, because these dusts frequently have small size distributions, irregular morphology, and high specific surface areas, they can have very high gas flow resistance resulting in hot-gas filter system operating problems. Typical of gasification chars, the hot-gas filter dustcakes produced at the Power Systems Development Facility (PSDF) during recent coal gasification tests have had very high flow resistance (Martin et al, 2002). The filter system has been able to successfully operate, but pressure drops have been high and filter cleaning must occur very frequently. In anticipation of this problem, a study was conducted to investigate ways of reducing dustcake pressure drop. This paper will discuss the efficacy of adding low-flow-resistance particulate matter to the high-flow-resistance char dustcake to reduce dustcake pressure drop. The study had two parts: a laboratory screening study and confirming field measurements at the PSDF.

  16. PAH emission from various industrial stacks

    Microsoft Academic Search

    Hsi-Hsien Yang; Wen-Jhy Lee; Shui-Jen Chen; Soon-Onn Lai

    1998-01-01

    The emission of polycyclic aromatic hydrocarbons (PAHs) from various industrial stacks (blast furnace, basic oxygen furnace, coke oven, electric arc furnace, heavy oil plant, power plant and cement plant) in southern Taiwan were investigated. PAH concentrations (?g\\/N m3) and PAH emission factors (?g\\/kg feedstock) were determined. In addition to these eight stationary industrial stacks, an industrial waste incinerator, a diesel

  17. A novel optical scattering collection system for particulate monitoring applications

    SciTech Connect

    Bernacki, B.E.; Miller, A.C. Jr. [Oak Ridge National Lab., TN (United States); Nuspliger, R.J. [Environmental Systems Corp., Knoxville, TN (United States)

    1996-05-01

    Light collecting systems often require radically different optical surfaces than those commonly found in optical imaging systems. An optical particulate monitor must probe a volume in emission stacks to obtain a good statistical distribution of suspended particles. However, ideal imaging systems map object planes into conjugate image planes and can probe only small volumes. The authors describe the design, fabrication and performance of a novel optical scattering collection system that exploits precision-engineered reflective conical surfaces (axicons) in a telescopic arrangement that maps a line in object space onto the detector plane in image space. Such non-spherical surfaces are nearly impossible to fabricate using traditional methods, but can readily be made using the deterministic method of single-point diamond turning. In addition to complex optical surfaces, single-point diamond turning also makes possible the precision engineering of reference surfaces useful for built-in alignment of multiple surfaces and rapid assembly of the finished system.

  18. PARTICULATE EMISSION MEASUREMENTS FROM CONTROLLED CONSTRUCTION ACTIVITIES

    EPA Science Inventory

    The report summarized the results of field testing of the effectiveness of control measures for sources of fugitive particulate emissions found at construction sites. The effectiveness of watering temporary, unpaved travel surfaces on emissions of particulate matter with aerodyna...

  19. NONFERROUS INDUSTRY PARTICULATE EMISSIONS: SOURCE CATEGORY REPORT

    EPA Science Inventory

    The report gives results of the development of particulate emission factors based on cutoff size for inhalable particles for the nonferrous industry. After a review of available information characterizing particulate emissions from nonferrous plants, the data were summarized and ...

  20. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    SciTech Connect

    Gottesfeld, S. [Los Alamos National Lab., NM (United States)

    1995-09-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

  1. Stacking interactions in PUF?RNA complexes

    SciTech Connect

    Yiling Koh, Yvonne; Wang, Yeming; Qiu, Chen; Opperman, Laura; Gross, Leah; Tanaka Hall, Traci M.; Wickens, Marvin (NIH); (UW)

    2012-07-02

    Stacking interactions between amino acids and bases are common in RNA-protein interactions. Many proteins that regulate mRNAs interact with single-stranded RNA elements in the 3' UTR (3'-untranslated region) of their targets. PUF proteins are exemplary. Here we focus on complexes formed between a Caenorhabditis elegans PUF protein, FBF, and its cognate RNAs. Stacking interactions are particularly prominent and involve every RNA base in the recognition element. To assess the contribution of stacking interactions to formation of the RNA-protein complex, we combine in vivo selection experiments with site-directed mutagenesis, biochemistry, and structural analysis. Our results reveal that the identities of stacking amino acids in FBF affect both the affinity and specificity of the RNA-protein interaction. Substitutions in amino acid side chains can restrict or broaden RNA specificity. We conclude that the identities of stacking residues are important in achieving the natural specificities of PUF proteins. Similarly, in PUF proteins engineered to bind new RNA sequences, the identity of stacking residues may contribute to 'target' versus 'off-target' interactions, and thus be an important consideration in the design of proteins with new specificities.

  2. Evaluating user interfaces for stack mode viewing

    NASA Astrophysics Data System (ADS)

    Atkins, M. Stella; Kirkpatrick, Arthur E.; Knight, Adelle; Forster, Bruce

    2007-03-01

    The goal of this research was to evaluate two different stack mode layouts for 3D medical images - a regular stack mode layout where just the topmost image was visible, and a new stack mode layout, which included the images just before and after the main image. We developed stripped down user interfaces to test the techniques, and designed a look-alike radiology task using 3D artificial target stimuli implanted in the slices of medical image volumes. The task required searching for targets and identifying the range of slices containing the targets. Eight naive students participated, using a within-subjects design. We measured the response time and accuracy of subjects using the two layouts and tracked the eyegaze of several subjects while they performed the task. Eyegaze data was divided into fixations and saccades Subjects were 19% slower with the new stack layout than the standard stack layout, but 5 of the 8 subjects preferred the new layout. Analysis of the eyegaze data showed that in the new technique, the context images on both sides were fixated once the target was found in the topmost image. We believe that the extra time was caused by the difficulty in controlling the rate of scrolling, causing overshooting. We surmise that providing some contextual detail such as adjacent slices in the new stack mode layout is helpful to reduce cognitive load for this radiology look-alike task.

  3. Stacking interactions in PUF-RNA complexes.

    PubMed

    Koh, Yvonne Yiling; Wang, Yeming; Qiu, Chen; Opperman, Laura; Gross, Leah; Tanaka Hall, Traci M; Wickens, Marvin

    2011-04-01

    Stacking interactions between amino acids and bases are common in RNA-protein interactions. Many proteins that regulate mRNAs interact with single-stranded RNA elements in the 3' UTR (3'-untranslated region) of their targets. PUF proteins are exemplary. Here we focus on complexes formed between a Caenorhabditis elegans PUF protein, FBF, and its cognate RNAs. Stacking interactions are particularly prominent and involve every RNA base in the recognition element. To assess the contribution of stacking interactions to formation of the RNA-protein complex, we combine in vivo selection experiments with site-directed mutagenesis, biochemistry, and structural analysis. Our results reveal that the identities of stacking amino acids in FBF affect both the affinity and specificity of the RNA-protein interaction. Substitutions in amino acid side chains can restrict or broaden RNA specificity. We conclude that the identities of stacking residues are important in achieving the natural specificities of PUF proteins. Similarly, in PUF proteins engineered to bind new RNA sequences, the identity of stacking residues may contribute to "target" versus "off-target" interactions, and thus be an important consideration in the design of proteins with new specificities. PMID:21372189

  4. Process for particulate removal from coal liquids

    DOEpatents

    Rappe, Gerald C. (Macungie, PA)

    1983-01-01

    Suspended solid particulates are removed from liquefied coal products by first subjecting such products to hydroclone action for removal in the underflow of the larger size particulates, and then subjecting the overflow from said hydroclone action, comprising the residual finer particulates, to an electrostatic field in an electrofilter wherein such finer particulates are deposited in the bed of beads of dielectric material on said filter. The beads are periodically cleaned by backwashing to remove the accumulated solids.

  5. Removal of mercury from stack gases by activated carbon

    SciTech Connect

    Vidic, R.D. [Univ. of Pittsburgh, PA (United States)

    1995-10-01

    On combustion, the trace elements in the incinerator feed stream are partitioned between the bottom ash (slag) stream, and a flue gas stream containing suspended fly ash and vapors of volatile elements or compounds. A further partitioning of the flue gas stream takes place in the particulate emission control devices that efficiently remove larger fly ash particles but are less efficient for vapors and finer particles. Environmental control agencies, researchers, and general public have become increasingly concerned with the mobilization of trace elements to the environment from solid and hazardous waste incinerators. Mercury is the trace element of particular concern since, during combustion, most of the mercury present in the influent stream is transferred into the vapor phase due to its high volatility. There is a considerable evidence in the literature that currently used pollution abatement technologies (flue gas clean-up and particulate control devices) are not capable of controlling gas phase mercury emissions. Activated carbon adsorption is a unit process that offers great promise for achieving high quality air emissions with respect to mercury and other trace elements that might be present in gases emitted from solid and hazardous waste incinerators. This study is designed to evaluate the rate of vapor-phase mercury removal by virgin and sulfur impregnated activated carbons under various process conditions. The specific process conditions that will be evaluated for their effect on the rate and mechanism of mercury uptake include temperature, moisture content, oxygen partial pressure, and presence of other compounds and trace elements in the vapor-phase. Accurate description of the kinetics of mercury removal by activated carbon is an essential component in establishing design procedures that would ensure successful application of this efficient technology for mercury control.

  6. Comparison of particulate verification techniques study

    Microsoft Academic Search

    Rachel Rivera

    2006-01-01

    The efficacy of five particulate verification techniques on four types of materials was studied. Statistical Analysis Software\\/JMP 6.0 was used to create a statistically valid design of experiments. In doing so, 35 witness coupons consisting of the four types of materials being studied, were intentionally contaminated with particulate fallout. Image Analysis was used to characterize the extent of particulate fallout

  7. Particulate emissions from concentrated animal feeding operations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrated animal feeding operations (CAFOs), including open beef cattle feedlots, swine facilities, and poultry facilities, can emit large amounts of particulate matter, including TSP (total suspended particulates), PM10 (particulate matter with equivalent aerodynamic diameter of 10 mm or less) a...

  8. Apparatus for combustion of solid particulate fuel

    Microsoft Academic Search

    Whitfield

    1990-01-01

    This patent describes an apparatus for the combustion of solid particulate fuel. It comprises: a stationary grate including a perforated plate for receiving the solid particulate fuel; displaceable means positioned in a plane above the grate, movement of the displaceable means displacing spent solid particulate fuel from the stationary grate. The displaceable means including a rotatable member; and a burning

  9. Monitoring of particulate matter outdoors

    Microsoft Academic Search

    W. E. Wilson; Judith C. Chow; Candis Claiborn; Wei Fusheng; Johann Engelbrecht; John G. Watson

    2002-01-01

    Recent studies of the size and composition of atmospheric particulate matter (PM) have demonstrated the usefulness of separating atmospheric PM into its fine and coarse components. The need to measure the mass and composition of fine and coarse PM separately has been emphasized by research in exposure, epidemiology, and toxicology of atmospheric PM. This paper provides a background on the

  10. MONITORING OF PARTICULATE MATTER OUTDOORS

    EPA Science Inventory

    Recent studies of the size and composition of atmospheric particulate matter (PM) have demonstrated the usefulness of separating atmospheric PM into its fine and coarse components. The need to measure the mass and composition of fine and coarse PM separately has been emphasized b...

  11. Source Testing for Particulate Matter.

    ERIC Educational Resources Information Center

    DeVorkin, Howard

    Developed for presentation at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, this outline covers procedures for the testing of particulate matter. These are: (1) basic requirements, (2) information required, (3) collection of samples, (4) processing of samples, (5)…

  12. The Morgantown Energy Technology Center`s particulate cleanup program

    SciTech Connect

    Dennis, R.A.

    1995-12-01

    The development of integrated gasification combined cycle (IGCC) and pressurized fluidized-bed combustion (PFBC) power systems has made it possible to use coal while still protecting the environment. Such power systems significantly reduce the pollutants associated with coal-fired plants built before the 1970s. This superior environmental performance and related high system efficiency is possible, in part, because particulate gas-stream cleanup is conducted at high-temperature and high-pressure process conditions. A main objective of the Particulate Cleanup Program at the Morgantown Energy Technology Center (METC) is to ensure the success of the CCT demonstration projects. METC`s Particulate Cleanup Program supports research, development, and demonstration in three areas: (1) filter-system development, (2) barrier-filter component development, and (3) ash and char characterization. The support is through contracted research, cooperative agreements, Cooperative Research And Development Agreements (CRADAs), and METC`s own in-house research. This paper describes METC`s Particulate Cleanup Program.

  13. Low exhaust temperature electrically heated particulate matter filter system

    DOEpatents

    Gonze, Eugene V. (Pinckney, MI); Paratore, Jr., Michael J. (Howell, MI); Bhatia, Garima (Bangalore, IN)

    2012-02-14

    A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.

  14. Manifold gasket accommodating differential movement of fuel cell stack

    DOEpatents

    Kelley, Dana A. (New Milford, CT); Farooque, Mohammad (Danbury, CT)

    2007-11-13

    A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.

  15. High Voltage Marx Generator Implementation using IGBT Stacks

    Microsoft Academic Search

    Jong-Hyun Kim; Byung-Duk Min; Sergey Shenderey; Geun-Hie Rim

    2007-01-01

    High voltage Marx generator implementation using IGBT (Insulated Gate Bipolar Transistor) stacks is proposed in this paper. To protect the Marx generator at the moment of breakdown, AOCP (Active Over-Current Protection) part is included. The Marx generator is composed of 12 stages and each stage is made of IGBT stacks, two diode stacks, and capacitors. IGBT stack is used as

  16. High voltage pulse power implementation using IGBT stacks

    Microsoft Academic Search

    Jong-Hyun Kim; Myung-Hyo Ryu; Byung-Duk Min; Ju-Won Baek; Jong-Soo Kim; Geun-Hie Rim

    2006-01-01

    High voltage pulse power implementation using IGBT stacks is proposed in this paper. High voltage pulse power implementation uses Marx circuit as the main circuit. The Marx circuit is composed of 12 stages and each stage is made of IGBT stack, two diode stacks, and capacitor. Diode stacks and inductor are used to charge high voltage capacitor of each stage

  17. Stacking in colloidal nanoplatelets: tuning excitonic properties.

    PubMed

    Guzelturk, Burak; Erdem, Onur; Olutas, Murat; Kelestemur, Yusuf; Demir, Hilmi Volkan

    2014-12-23

    Colloidal semiconductor quantum wells, also commonly known as nanoplatelets (NPLs), have arisen among the most promising materials for light generation and harvesting applications. Recently, NPLs have been found to assemble in stacks. However, their emerging characteristics essential to these applications have not been previously controlled or understood. In this report, we systematically investigate and present excitonic properties of controlled column-like NPL assemblies. Here, by a controlled gradual process, we show that stacking in colloidal quantum wells substantially increases exciton transfer and trapping. As NPLs form into stacks, surprisingly we find an order of magnitude decrease in their photoluminescence quantum yield, while the transient fluorescence decay is considerably accelerated. These observations are corroborated by ultraefficient Förster resonance energy transfer (FRET) in the stacked NPLs, in which exciton migration is estimated to be in the ultralong range (>100 nm). Homo-FRET (i.e., FRET among the same emitters) is found to be ultraefficient, reaching levels as high as 99.9% at room temperature owing to the close-packed collinear orientation of the NPLs along with their large extinction coefficient and small Stokes shift, resulting in a large Förster radius of ?13.5 nm. Consequently, the strong and long-range homo-FRET boosts exciton trapping in nonemissive NPLs, acting as exciton sink centers, quenching photoluminescence from the stacked NPLs due to rapid nonradiative recombination of the trapped excitons. The rate-equation-based model, which considers the exciton transfer and the radiative and nonradiative recombination within the stacks, shows an excellent match with the experimental data. These results show the critical significance of stacking control in NPL solids, which exhibit completely different signatures of homo-FRET as compared to that in colloidal nanocrystals due to the absence of inhomogeneous broadening. PMID:25469555

  18. Assessment of the 3420 Building Filtered Exhaust Stack Sampling Probe Location

    SciTech Connect

    Glissmeyer, John A.; Flaherty, Julia E.

    2010-07-16

    Pacific Northwest National Laboratory performed several tests in the exhaust air discharge from the new 3420 Building Filtered Exhaust Stack to determine whether the air sampling probe for emissions monitoring for radionuclides is acceptable. The method followed involved adopting the results of a previously performed test series from a system with a similar configuration, followed by several tests on the actual system to verify the applicability of the previously performed tests. The qualification criteria for these types of stacks include metrics concerning 1) uniformity of air velocity, 2) sufficiently small flow angle with respect to the axis of the duct, 3) uniformity of tracer gas concentration, and 4) uniformity tracer particle concentration.

  19. Assessment of the 3410 Building Filtered Exhaust Stack Sampling Probe Location

    SciTech Connect

    Glissmeyer, John A.; Flaherty, Julia E.

    2010-07-16

    Pacific Northwest National Laboratory performed several tests in the exhaust air discharge from the new 3410 Building Filtered Exhaust Stack to determine whether the air sampling probe for emissions monitoring for radionuclides is acceptable. The method followed involved adopting the results of a previously performed test series from a system with a similar configuration, followed by several tests on the actual system to verify the applicability of the previously performed tests. The qualification criteria for these types of stacks include metrics concerning 1) uniformity of air velocity, 2) sufficiently small flow angle with respect to the axis of the duct, 3) uniformity of tracer gas concentration, and 4) uniformity tracer particle concentration.

  20. Inflatable containment diaphragm for sealing and removing stacks

    DOEpatents

    Meskanick, G.R.; Rosso, D.T.

    1993-04-13

    A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

  1. Crystallographic stacking faults in antiferromagnetically coupled media

    NASA Astrophysics Data System (ADS)

    Zambon, C.; Holloway, L.; Antel, W. J.; Laidler, H.; Girt, E.; Harkness, S. D.

    2002-05-01

    Synchrotron x-ray scattering has been used to examine stacking faults in the constituent layers of an antiferromagnetically coupled (AFC) media film. By varying the x-ray incident angle, we have varied the x-ray penetration depth and, hence, the layer under examination. Three films were studied, one consisting of a full AFC media structure and the other two consisting of a single magnetic layer with the thicknesses of the constituent layers in the AFC medium. The stacking faults in the bottom magnetic layer were investigated using the single layer film. The stacking fault density in the top AFC media layer was measured using careful depth profiling to ensure that the penetration depth of the x rays remained within the top layer. We were unable to estimate the stacking faults in the bottom layer film but the stacking fault densities are constant at approximately 5% for the top layer of the AFC media and the top layer single film within a relatively large error of 3%.

  2. Technical description of Stack 296-B-5

    SciTech Connect

    Ridge, T.M.

    1994-11-15

    Of particular concern to facilities on the Hanford site is Title 40, Code of Federal Regulations, Chapter 40, Part 61, Subpart H, ``National emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities.`` Assessments of facility stacks and potential radionuclide emissions determined whether these stacks would be subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. Stack 296-B-5 exhausts 221-BB building which houses tanks containing B Plant steam condensate and B Plant process condensate from the operation of the low-level waste concentrator. The assessment of potential radionuclide emissions from the 296-B-5 stack resulted in an effective dose equivalent to the maximally exposed individual of less than 0.1 millirem per year. Therefore, the stack is not subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. However, the sampling and monitoring system must be in compliance with the Environmental Compliance Manual, WHC-CM-7-5. Currently, 296-B-5 is sampled continuously with a record sampler and continuous air monitor (CAM).

  3. Method and apparatus for the separation of a gas-solids mixture in a circulating fluidized bed reactor

    DOEpatents

    Vimalchand, Pannalal (Birmingham, AL); Liu, Guohai (Birmingham, AL); Peng, WanWang (Birmingham, AL)

    2010-08-10

    The system of the present invention includes a centripetal cyclone for separating particulate material from a particulate laden gas solids stream. The cyclone includes a housing defining a conduit extending between an upstream inlet and a downstream outlet. In operation, when a particulate laden gas-solids stream passes through the upstream housing inlet, the particulate laden gas-solids stream is directed through the conduit and at least a portion of the solids in the particulate laden gas-solids stream are subjected to a centripetal force within the conduit.

  4. Assessment of hot particulate removal systems for IGCC and PFBC advanced power systems

    SciTech Connect

    Klett, M.G.; Rutkowski, M.D.; Zaharchuk, R. [Parsons Power Group Inc., Reading, PA (United States)

    1996-12-31

    The National Research Council (NRC) Committee on the Strategic Assessment of the DOE Coal Program addressed the future role of DOE in research, development, demonstration, (RD and D) and commercial application programs on coal-based technologies. Parsons Power Group Inc. assisted DOE in assessing expected results of hot gas cleanup systems RD and D for advanced IGCC and PFBC. The technical approach to conducting the assessment consisted of three parts: determination of hot gas cleanup status, determination of hot gas cleanup systems cost and performance sensitivities, and the identification of DOE`s specific goals, stages and time frames. The hot gas cleanup technologies were divided into three categories, particulate collection systems, hot gas desulfurization systems, and trace contaminants removal systems. This presentation covers the assessment of the particulate removal systems. Information was obtained from a literature review, a phone survey of selected key people, and the Parsons Power Information base. Significant tests and results were summarized and development progress noted. To determine the sensitivity of particulate cleanup devices on overall system costs and performance, existing IGCC and PFBC plant designs with hot gas cleanup were used as baselines for analysis. The status of particulate removal system development relative to program goals were compared against testing results, cost/benefits and alternative technologies, and an assessment were made as to the time frame for commercialization. Findings of the assessment will be presented.

  5. Effects of Endwall Geometry and Stacking on Two-Stage Supersonic Turbine Performance

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel J.; Griffin, Lisa W.; Huber, Frank W.; Sondak, Douglas L.; Turner, Jim (Technical Monitor)

    2002-01-01

    The drive towards high-work turbines has led to designs which can be compact, transonic, supersonic, counter rotating, or use a dense drive gas. These aggressive designs can lead to strong secondary flows and airfoil flow separation. In many cases the secondary and separated flows can be minimized by contouring the hub/shroud endwalls and/or modifying the airfoil stacking. In this study, three-dimensional unsteady Navier-Stokes simulations were performed to study three different endwall shapes between the first-stage vanes and rotors, as well as two different stackings for the first-stage vanes. The predicted results indicate that changing the stacking of the first-stage vanes can significantly impact endwall separation (and turbine performance) in regions where the endwall profile changes.

  6. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2005-01-25

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

  7. Radiation Tolerant Intelligent Memory Stack (RTIMS)

    NASA Technical Reports Server (NTRS)

    Ng, Tak-kwong; Herath, Jeffrey A.

    2006-01-01

    The Radiation Tolerant Intelligent Memory Stack (RTIMS), suitable for both geostationary and low earth orbit missions, has been developed. The memory module is fully functional and undergoing environmental and radiation characterization. A self-contained flight-like module is expected to be completed in 2006. RTIMS provides reconfigurable circuitry and 2 gigabits of error corrected or 1 gigabit of triple redundant digital memory in a small package. RTIMS utilizes circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuitries are stacked into a module of 42.7mm x 42.7mm x 13.00mm. Triple module redundancy, current limiting, configuration scrubbing, and single event function interrupt detection are employed to mitigate radiation effects. The mitigation techniques significantly simplify system design. RTIMS is well suited for deployment in real-time data processing, reconfigurable computing, and memory intensive applications.

  8. Intelligent Control System of Stack-boiler

    NASA Astrophysics Data System (ADS)

    Jing, Li; Jingxia, Niu; Jianhua, Lang; Shaofeng, Li; Zhi, Li

    Boiler combustion control system's basic task is to make fuel burn calories adapt to the needs of the water temperature and ensure the economical combustion and the safe operation. In the foundations which have analyzed the stack-boiler's work process and control system structure, the system designed by using the self-learning and self-optimizing fuzzy control system of the PC to make air/coal ratio achieve the best and realize the optimized combustion; through PLC to accelerate the speed of response to the boiler, and speed up the PC to optimize the speed and realize the double loop control system for stack-boiler. The control system in premise of the stack-boiler reaches the goal of the load to achieve the highest efficiency of the boiler combustion.

  9. Polarization signatures of airborne particulates

    NASA Astrophysics Data System (ADS)

    Raman, Prashant; Fuller, Kirk A.; Gregory, Don A.

    2013-07-01

    Exploratory research has been conducted with the aim of completely determining the polarization signatures of selected particulates as a function of wavelength. This may lead to a better understanding of the interaction between electromagnetic radiation and such materials, perhaps leading to the point detection of bio-aerosols present in the atmosphere. To this end, a polarimeter capable of measuring the complete Mueller matrix of highly scattering samples in transmission and reflection (with good spectral resolution from 300 to 1100 nm) has been developed. The polarization properties of Bacillus subtilis (surrogate for anthrax spore) are compared to ambient particulate matter species such as pollen, dust, and soot. Differentiating features in the polarization signatures of these samples have been identified, thus demonstrating the potential applicability of this technique for the detection of bio-aerosol in the ambient atmosphere.

  10. SOUTHERN FINE PARTICULATE MONITORING PROJECT

    SciTech Connect

    Ashley D. Williamson

    2002-01-31

    This quarterly report presents results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October--December, 2001 study period. The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. The persistent daily trends described in the previous quarterly report are seen in the fall particulate data, superimposed on the seasonal trend toward lower concentrations in the cooler months. Some instrumental issues were noted with the APS and the sulfate monitoring instruments, as described in the main report.

  11. Pressurized Testing of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

    SciTech Connect

    J. E. O'Brien; X. Zhang; G. K. Housley; K. DeWall; L. Moore-McAteer; G. Tao

    2012-06-01

    A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate cell dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this paper.

  12. SOUTHERN FINE PARTICULATE MONITORING PROJECT

    SciTech Connect

    Ashley D. Williamson

    2001-07-01

    This is the third quarterly progress report of the ''Southern Fine Particulate Monitoring Project'', funded by the U.S. Department of Energy's National Energy Technology Laboratory under DOE Cooperative Agreement No. DE-FC26-00NT40770 to Southern Research Institute (SRI). In this two year project SRI will conduct detailed studies of ambient fine particulate matter in the Birmingham, AL metropolitan area. Project objectives include: Augment existing measurements of primary and secondary aerosols at an established urban southeastern monitoring site; Make a detailed database of near-continuous measurements of the time variation of fine particulate mass, composition, and key properties (including particle size distribution); Apply the measurements to source attribution, time/transport properties of fine PM, and implications for management strategies for PM{sub 2.5}; and Validate and compare key measurement methods used in this study for applicability within other PM{sub 2.5} research by DOE-FE, EPA, NARSTO, and others. During the third project quarter, the new SRI air monitoring shelter and additional instruments were installed at the site. Details include: Installation of Radiance Research M903 Nephelometer; Installation of SRI air monitoring shelter at North Birmingham Site; Relocation of instruments from SEARCH shelter to SRI shelter; Installation of Rupprecht & Patashnick 8400 Sulfate Monitor; Assembly and initial laboratory testing for particulate sulfate monitor of Harvard design; Efficiency testing of particle sizing instrument package at SRI lab; Preparation for the Eastern Supersite July measurement intensive program; and Continued monitoring with TEOM and particle sizing instruments.

  13. Particulate emissions: Evaluating removal methods

    Microsoft Academic Search

    1997-01-01

    Next month, the US Environmental Protection Agency expects to finalize a new set of regulations for the removal of airborne particulate matter. The so-called PM-2.5 Standard would set thresholds for the removal of particles under 1 micrometer (μm) in diameter. Current EPA rules regulate airborne particles that are 2.5--10 μm dia. The impetus behind the controversial PM-2.5 Standard comes from

  14. Nonlinearly stacked low noise turbofan stator

    NASA Technical Reports Server (NTRS)

    Schuster, William B. (Inventor); Kontos, Karen B. (Inventor); Weir, Donald S. (Inventor); Nolcheff, Nick A. (Inventor); Gunaraj, John A. (Inventor)

    2009-01-01

    A nonlinearly stacked low noise turbofan stator vane having a characteristic curve that is characterized by a nonlinear sweep and a nonlinear lean is provided. The stator is in an axial fan or compressor turbomachinery stage that is comprised of a collection of vanes whose highly three-dimensional shape is selected to reduce rotor-stator and rotor-strut interaction noise while maintaining the aerodynamic and mechanical performance of the vane. The nonlinearly stacked low noise turbofan stator vane reduces noise associated with the fan stage of turbomachinery to improve environmental compatibility.

  15. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2004-02-17

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

  16. Testing of Bluetooth protocol stack using emulator

    NASA Astrophysics Data System (ADS)

    Ye, Dongxiang; Jiang, Zhong'ao; Lin, Hong; Gao, Qiang

    2001-10-01

    Bluetooth is a promising new technology for short range wireless connectivity between mobile devices. Nevertheless, before the massive products come into the market, reliability of protocol stack and profiles, and interoperability of different Bluetooth products from different vendors are yet to overcome. In this article, we proposed an conformance testing architecture using emulator for different protocol stacks. Our purpose to use emulator instead of hardware is to provide a higher degree of control in testing the system for setting various parameters and test the protocol for a large number of nodes.

  17. 21 CFR 868.6885 - Medical gas yoke assembly.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...medical gas yoke assembly is a device intended to connect medical gas cylinders to regulators or needle valves to supply gases for anesthesia or respiratory therapy. The device may include a particulate filter. (b) Classification. Class I (general...

  18. 21 CFR 868.6885 - Medical gas yoke assembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...medical gas yoke assembly is a device intended to connect medical gas cylinders to regulators or needle valves to supply gases for anesthesia or respiratory therapy. The device may include a particulate filter. (b) Classification. Class I (general...

  19. 21 CFR 868.6885 - Medical gas yoke assembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...medical gas yoke assembly is a device intended to connect medical gas cylinders to regulators or needle valves to supply gases for anesthesia or respiratory therapy. The device may include a particulate filter. (b) Classification. Class I (general...

  20. 21 CFR 868.6885 - Medical gas yoke assembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...medical gas yoke assembly is a device intended to connect medical gas cylinders to regulators or needle valves to supply gases for anesthesia or respiratory therapy. The device may include a particulate filter. (b) Classification. Class I (general...

  1. Polychlorinated Biphenyl Recovery Efficiency from Stack Gas and Ambient Air

    Microsoft Academic Search

    Jerry W. Jackson; Daniel P. Y. Chang

    1977-01-01

    Polychlorinated biphenyls (PCBs) are now recognized as presenting a severe environmental hazard because of their toxicity and persistence in the environment. High temperature combustion has been shown to be an effective method for destroying these compounds. Unfortunately, few facilities are available for their destruction. As part of a feasibility study to convert a liquid-waste incinerator designed for waste fuel to

  2. Asymmetrical reverse vortex flow due to induced-charge electro-osmosis around carbon stacking structures.

    PubMed

    Sugioka, Hideyuki

    2011-05-01

    Broken symmetry of vortices due to induced-charge electro-osmosis (ICEO) around stacking structures is important for the generation of a large net flow in a microchannel. Following theoretical predictions in our previous study, we herein report experimental observations of asymmetrical reverse vortex flows around stacking structures of carbon posts with a large height (~110 ?m) in water, prepared by the pyrolysis of a photoresist film in a reducing gas. Further, by the use of a coupled calculation method that considers boundary effects precisely, the experimental results, except for the problem of anomalous flow reversal, are successfully explained. That is, unlike previous predictions, the precise calculations here show that stacking structures accelerate a reverse flow rather than suppressing it for a microfluidic channel because of the deformation of electric fields near the stacking portions; these structures can also generate a large net flow theoretically in the direction opposite that of a previous prediction for a standard vortex flow. Furthermore, by solving the one-dimensional Poisson-Nernst-Plank (PNP) equations in the presence of ac electric fields, we find that the anomalous flow reversal occurs by the phase retardation between the induced diffuse charge and the tangential electric field. In addition, we successfully explain the nonlinearity of the flow velocity on the applied voltage by the PNP analysis. In the future, we expect to improve the pumping performance significantly by using stacking structures of conductive posts along with a low-cost process. PMID:21728661

  3. MERCURY CONTROL WITH THE ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller; Grant E. Dunham; Michelle R. Olderbak

    2002-02-01

    Since 1995, DOE has supported development of a new concept in particulate control, called the advanced hybrid particulate collector (AHPC). The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas-solid contactor. The objective of the three-task project is to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach includes bench-scale batch testing that ties the new work to previous results and links results with larger-scale pilot testing with real flue gas on a coal-fired combustion system, pilot-scale testing on a coal-fired combustion system with both a pulse-jet baghouse and an AHPC to prove or disprove the research hypotheses, and field demonstration pilot-scale testing at a utility power plant to prove scaleup and demonstrate longer-term mercury control. This project, if successful, will demonstrate at the pilot-scale level a technology that would provide a cost-effective technique to accomplish control of mercury emissions and, at the same time, greatly enhance fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution to a large segment of the U.S. utility industry as well as other industries requiring mercury control.

  4. Stacking of SKA data: comparing uv-plane and image-plane stacking

    E-print Network

    Knudsen, K K; Vlemmings, W; Conway, J; Marti-Vidal, I

    2015-01-01

    Stacking as a tool for studying objects that are not individually detected is becoming popular even for radio interferometric data, and will be widely used in the SKA era. Stacking is typically done using imaged data rather than directly using the visibilities (the uv-data). We have investigated and developed a novel algorithm to do stacking using the uv-data. We have performed exten- sive simulations comparing to image-stacking, and summarize the results of these simulations. Furthermore, we disuss the implications in light of the vast data volume produced by the SKA. Having access to the uv-stacked data provides a great advantage, as it allows the possibility to properly analyse the result with respect to calibration artifacts as well as source properties such as size. For SKA the main challenge lies in archiving the uv-data. For purposes of robust stacking analysis, it would be strongly desirable to either keep the calibrated uv-data at least in an aver- age form, or implement a stacking queue where stacki...

  5. Preventing Molecular and Particulate Infiltration in a Confined Volume

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.

    1999-01-01

    Contaminants from an instrument's self-generated sources or from sources external to the instrument may degrade its critical surfaces and/or create an environment which limits the instrument's intended performance. Analyses have been carried out on a method to investigate the required purging flow of clean, dry gas to prevent the ingestion of external contaminants into the instrument container volume. The pressure to be maintained and the required flow are examined in terms of their effectiveness in preventing gaseous and particulate contaminant ingestion and abatement of self-generated contaminants in the volume. The required venting area or the existing volume venting area is correlated to the volume to be purged, the allowable pressure differential across the volume, the external contaminant partial pressure, and the sizes of the ambient particulates. The diffusion of external water vapor into the volume while it was being purged was experimentally obtained in terms of an infiltration time constant. That data and the acceptable fraction of the outside pressure into the volume indicate the required flow of purge gas expressed in terms of volume change per unit time. The exclusion of particulates is based on the incoming velocity of the particles and the exit flow speed and density of the purge gas. The purging flow pressures needed to maintain the required flows through the vent passages are indicated. The purge gas must prevent or limit the entrance of the external contaminants to the critical locations of the instrument. It should also prevent self- contamination from surfaces, reduce material outgassing, and sweep out the outgassed products. Systems and facilities that can benefit from purging may be optical equipment, clinical facilities, manufacturing facilities, clean rooms, and other systems requiring clean environments.

  6. TEST RESULTS OF HIGH TEMPERATURE STEAM/CO2 CO-ELECTROLYSIS IN A 10-CELL STACK

    SciTech Connect

    James E. O'Brien; Joseph J. Hartvigsen

    2007-06-01

    High temperature coelectrolysis experiments with CO2 / H2O mixtures were performed in a 10-cell planar solid oxide stack. Results indicated that stack apparent ASR values were shown not to vary significantly between pure steam electrolysis and steam / CO2 coelectrolysis values. Product gas compositions measured via an online micro gas chromatograph (GC) showed excellent agreement to predictions obtained from a chemical equilibrium coelectrolysis model developed for this study. Experimentally determined open cell potentials and thermal neutral voltages for coelectrolysis compared favorably to predictions obtained from a chemical equilibrium coelectrolysis and energy balance model, also developed for this study.

  7. 40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

  8. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

  9. 40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

  10. 40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  11. 40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  12. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  13. 40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  14. 40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  15. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  16. 40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  17. 40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  18. 40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  19. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  20. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  1. 40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

  2. Gas sampling system for reactive gas-solid mixtures

    DOEpatents

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1989-01-01

    An apparatus and method for sampling a gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extend in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  3. Gas sampling system for reactive gas-solid mixtures

    DOEpatents

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1990-01-01

    An apparatus and method for sampling gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extends in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  4. YIELD IMPROVEMENT CASE STUDY: STACKED SPRING CAPS

    E-print Network

    Beckermann, Christoph

    ), and the total height is 1.7". The cap is cast from WCB steel in a no-bake sand mold, with a final casting weight mold box stacking arrangements. In this paper, `yield' is defined as the total weight of the castings produced by a mold assembly divided by the total weight of the melt poured to produce the castings

  5. Explosive demolition of K East Reactor Stack

    ScienceCinema

    None

    2010-09-02

    Using $420,000 in Recovery Act funds, the Department of Energy and contractor CH2M HILL Plateau Remediation Company topped off four months of preparations when they safely demolished the exhaust stack at the K East Reactor and equipment inside the reactor building on July 23, 2010.

  6. ESSENTIAL DIMENSION AND ALGEBRAIC STACKS PATRICK BROSNAN

    E-print Network

    Brosnan, Patrick

    that in Definition 1.1 the essential dimension of a depends on the field L. We write ed a instead of ed(a, LESSENTIAL DIMENSION AND ALGEBRAIC STACKS PATRICK BROSNAN , ZINOVY REICHSTEIN , AND ANGELO VISTOLI Abstract. Essential dimension is a numerical invariant of an algebraic group G introduced by J. Buhler

  7. Development of stacked multiple bandgap solar cells

    Microsoft Academic Search

    R. P. Ruth; J. J. Coleman; S. W. Zehr; R. D. Dupuis; H. T. Yang; D. L. Miller; P. D. Dapkus

    1979-01-01

    Stacked multiple bandgap solar cells utilize separate junctions or solar cells or selected properties which are combined in series both optically and electrically to obtain higher conversion efficiencies than can be achieved by any of the cells individually. Basic requirements for the successful fabrication of high efficiency tandem structures will be defined, and the apparent practical limitations on the formation

  8. Arrays of stacked metal coordination compounds

    DOEpatents

    Bulkowski, J.E.

    1986-10-21

    A process is disclosed for preparing novel arrays of metal coordination compounds characterized by arrangement of the metal ions, separated by a linking agent, in stacked order one above the other. The process permits great flexibility in the design of the array. For example, layers of different composition can be added to the array at will. 3 figs.

  9. A study of flow through stacked screens

    Microsoft Academic Search

    1992-01-01

    This paper describes numerical and experimental studies on the pressure loss characteristics of the flow through stacked screens. The flow through each screen is simulated as a core outside a boundary layer developing along the surface of the wire consisting of the screen. Within the core, the flow is modeled as one?dimensional for simplicity, and as two?dimensional for a more

  10. Protocols stack & connection establishment in Bluetooth radio

    Microsoft Academic Search

    M. A. R. Chaudhry; M. I. Sheikh

    2002-01-01

    Some of the issues to be considered in the design of the higher layers of its protocol stack are those that allow the Bluetooth module to be easily integrated into any existing device that may benefit from being connected. Further, for rapid acceptance into the market, it should be possible for existing applications developed over conventional protocols to be easily

  11. SRS reactor stack plume marking tests

    SciTech Connect

    Petry, S.F.

    1992-03-01

    Tests performed in 105-K in 1987 and 1988 demonstrated that the stack plume can successfully be made visible (i.e., marked) by introducing smoke into the stack breech. The ultimate objective of these tests is to provide a means during an emergency evacuation so that an evacuee can readily identify the stack plume and evacuate in the opposite direction, thus minimizing the potential of severe radiation exposure. The EPA has also requested DOE to arrange for more tests to settle a technical question involving the correct calculation of stack downwash. New test canisters were received in 1988 designed to produce more smoke per unit time; however, these canisters have not been evaluated, because normal ventilation conditions have not been reestablished in K Area. Meanwhile, both the authorization and procedure to conduct the tests have expired. The tests can be performed during normal reactor operation. It is recommended that appropriate authorization and procedure approval be obtained to resume testing after K Area restart.

  12. Removing Sulphur Dioxide From Stack Gases

    ERIC Educational Resources Information Center

    Slack, A. V.

    1973-01-01

    Process types, process concepts, claims and counterclaims, cost factors, and the level of developed technology for sulfur dioxide control in stack gases are focused upon and evaluated. Wet and dry processes as well as recovery and throwaway processes are compared. (BL)

  13. Development of mechanically stacked tandem concentrator cells

    SciTech Connect

    Cape, J.A.; Fraas, L.M.; McLeod, P.S.; Partain, L.D.

    1987-10-01

    Mechanically stacked, multijunction (MSMJ) solar cells offer an excellent prospect for significantly increased efficiencies in the near term. In this work, we examine several new concepts for a MSMJ solar cell. These MSMJ cell concepts include the following: A GaAsP cell grown on a GaP substrate for stacking onto a silicon cell; a GaSb cell grown lattice-matched on a GaSb substrate for stacking beneath a GaAs cell; and a Ge cell for stacking beneath a GaAs cell. The growth of GaAsP and of GaSb by vacuum chemical epitaxy and the development of GaSb solar cells are described. The development of a germanium solar cell and of a 26.1% GaAs/Ge MSMJ cell is also described. Finally, this work has identified approaches for achieving efficiencies with a MSMJ cell in excess of 30%. 19 refs., 18 figs., 7 tabs.

  14. Mercury Control With The Advanced Hybrid Particulate Collector

    SciTech Connect

    Stanley J. Miller; Ye Zhuang; Jay C. Almlie

    2004-12-31

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory Program Solicitation DE-FC26-01NT41184 and specifically addresses Technical Topical Area 4 - Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot Scale. The project team included the Energy & Environmental Research Center as the main contractor; W.L. Gore & Associates, Inc., as a technical and financial partner; and the Big Stone Plant operated by Otter Tail Power Company, host for the field-testing portion of the research. Since 1995, DOE has supported development of a new concept in particulate control called the advanced hybrid particulate collector (AHPC). The AHPC has been licensed to W.L. Gore and Associates, Inc., and is marketed as the Advanced Hybrid{trademark} filter by Gore. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC also appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas--solid contactor. The objective of the original five-task project was to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach included benchscale batch tests, larger-scale pilot testing with real flue gas on a coal-fired combustion system, and field demonstration at the 2.5-MW scale at a utility power plant to prove scale-up and demonstrate longer-term mercury control. The scope of work was modified to include an additional sixth task, initiated in April 2003. The objective of this task was to evaluate the mercury capture effectiveness of the AHPC when used with elemental mercury oxidation additives. This project, which is now in the final report phase, demonstrated at the pilot-scale level a technology that provides a cost-effective technique to control mercury and, at the same time, greatly enhances fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution for improved fine particulate control combined with effective mercury control for a large segment of the U.S. utility industry as well as other industries.

  15. Comparative analysis between the alveolar recruitment maneuver and breath stacking technique in patients with acute lung injury

    PubMed Central

    Porto, Elias Ferreira; Tavolaro, Kelly Cristiani; Kumpel, Claudia; Oliveira, Fernanda Augusta; Sousa, Juciaria Ferreira; de Carvalho, Graciele Vieira; de Castro, Antonio Adolfo Mattos

    2014-01-01

    Objective To compare the effectiveness of the alveolar recruitment maneuver and the breath stacking technique with respect to lung mechanics and gas exchange in patients with acute lung injury. Methods Thirty patients were distributed into two groups: Group 1 - breath stacking; and Group 2 - alveolar recruitment maneuver. After undergoing conventional physical therapy, all patients received both treatments with an interval of 1 day between them. In the first group, the breath stacking technique was used initially, and subsequently, the alveolar recruitment maneuver was applied. Group 2 patients were initially subjected to alveolar recruitment, followed by the breath stacking technique. Measurements of lung compliance and airway resistance were evaluated before and after the use of both techniques. Gas analyses were collected before and after the techniques were used to evaluate oxygenation and gas exchange. Results Both groups had a significant increase in static compliance after breath stacking (p=0.021) and alveolar recruitment (p=0.03), but with no significant differences between the groups (p=0.95). The dynamic compliance did not increase for the breath stacking (p=0.22) and alveolar recruitment (p=0.074) groups, with no significant difference between the groups (p=0.11). The airway resistance did not decrease for either groups, i.e., breath stacking (p=0.91) and alveolar recruitment (p=0.82), with no significant difference between the groups (p=0.39). The partial pressure of oxygen increased significantly after breath stacking (p=0.013) and alveolar recruitment (p=0.04), but there was no significant difference between the groups (p=0.073). The alveolar-arterial O2 difference decreased for both groups after the breath stacking (p=0.025) and alveolar recruitment (p=0.03) interventions, and there was no significant difference between the groups (p=0.81). Conclusion Our data suggest that the breath stacking and alveolar recruitment techniques are effective in improving the lung mechanics and gas exchange in patients with acute lung injury. PMID:25028951

  16. 3-D CFD MODEL OF A MULTI-CELL HIGH TEMPERATURE ELECTROLYSIS STACK

    SciTech Connect

    Grant Hawkes; James O'Brien; Carl Stoots; Brian Hawkes

    2009-05-01

    A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis stack performance and steam electrolysis in the Idaho National Laboratory (INL) Integrated Lab Scale (ILS) experiment. The model is made of 60 planar cells stacked on top of each other operated as Solid Oxide Electrolysis Cells (SOEC). Details of the model geometry are specific to a stack that was fabricated by Ceramatec, Inc. and tested at INL. Inlet and outlet plenum flow and distribution are considered. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density, and hydrogen production over a range of stack operating conditions. Variations in flow distribution and species concentration are discussed. End effects of flow and per-cell voltage are also considered.

  17. 3D CFD Model of a Multi-Cell High Temperature Electrolysis Stack

    SciTech Connect

    G.L. Hawkes; J. E. O'Brien; C. M. Stoots

    2007-11-01

    A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis stack performance and steam electrolysis in the Idaho National Laboratory Integrated Lab Scale (ILS) experiment. The model is made of 60 planar cells stacked on top of each other operated as Solid Oxide Electrolysis Cells (SOEC). Details of the model geometry are specific to a stack that was fabricated by Ceramatec, Inc1. and tested at the Idaho National Laboratory. Inlet and outlet plenum flow and distribution are considered. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT2. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC userdefined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation overpotential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Variations in flow distribution, and species concentration are discussed. End effects of flow and per-cell voltage are also considered.

  18. Role Of A TAS AOTF In A Commercial Stack Analyzer

    NASA Astrophysics Data System (ADS)

    Nelson, Robert L.

    1987-06-01

    A recent breakthrough in the growth of excellent quality single crystal thallium arsenic selenide (TAS) on a production basis has made it possible to build an electronically controlled acousto optic tunable filter (AOTF) capable of operating in the infrared. Such a filter with integral ultrasonic transducer can be used in place of mechanical filter wheels, spinning gas cells, moving mirrors, diffraction gratings and mechanical light choppers. The TAS AOTF produces an electronically controllable narrow band infrared filter capable of being tuned to any infrared frequency desired. It provides a chopped and tuned IR source that can be directed across the stack on any combustion process to measure the concentrations of CO, CO2, SO2, C2H6, CH4, NO, NO2, H2O, etc., simultaneously.

  19. FEASIBILITY OF A STACK INTEGRATED SOFC OPTICAL CHEMICAL SENSOR

    SciTech Connect

    Michael A. Carpenter

    2004-03-30

    The work performed during the UCR Innovative Concepts phase I program was designed to demonstrate the chemical sensing capabilities of nano-cermet SPR bands at solid oxide fuel cell operating conditions. Key to this proposal is that the materials choice used a YSZ ceramic matrix which upon successful demonstration of this concept, will allow integration directly onto the SOFC stack. Under the Innovative Concepts Program the University at Albany Institute for Materials (UAIM)/UAlbany School of NanoSciences and NanoEngineering synthesized, analyzed and tested Pa, and Au doped YSZ nano-cermets as a function of operating temperature and target gas exposure (hydrogen, carbon monoxide and 1-dodecanethiol). During the aforementioned testing procedure the optical characteristics of the nano-cermets were monitored to determine the sensor selectivity and sensitivity.

  20. Diesel particulate filter with zoned resistive heater

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-03-08

    A diesel particulate filter assembly comprises a diesel particulate filter (DPF) and a heater assembly. The DPF filters a particulate from exhaust produced by an engine. The heater assembly has a first metallic layer that is applied to the DPF, a resistive layer that is applied to the first metallic layer, and a second metallic layer that is applied to the resistive layer. The second metallic layer is etched to form a plurality of zones.

  1. An ultraviolet video technique for visualization of stack plumes and for measuring sulfur dioxide concentration and effluent velocity

    NASA Technical Reports Server (NTRS)

    Exton, R. J.

    1977-01-01

    Absorption spectroscopy utilizing a video sensing technique was investigated as a means of visualizing SO2 in power plant stack plumes and for measuring SO2 concentration and effluent velocity in these plumes. The absorption of SO2 is measured in the ultraviolet region by using the sky as a background source. An additional spectral channel is used to correct for particulate scattering encountered in coal fired power plant plumes. The video system also tracks fluctuations in the SO2 concentration which leads to the determination of an eddy convection velocity. Field measurements were performed to show that the eddy convection velocity is proportional to the average in-stack velocity and to empirically determine their relationship. It was concluded that the video absorption technique is an attractive method for remotely determining both SO2 concentration and plume velocity with the same instrument.

  2. Fuel gas desulfurization

    Microsoft Academic Search

    Ralph T. Yang; Ming-Shing Shen

    1981-01-01

    A method for removing sulfurous gases such as H.sub.2 S and COS from a fuel gas is disclosed wherein limestone particulates containing iron sulfide provide catalytic absorption of the H.sub.2 S and COS by the limestone. The method is effective at temperatures of 400.degree. C. to 700.degree. C. in particular.

  3. ADVANCED HOT GAS FILTER DEVELOPMENT

    Microsoft Academic Search

    E. S. Connolly; G. D. Forsythe

    1998-01-01

    Advanced, coal-based power plants will require durable and reliable hot gas filtration systems to remove particulate contaminants from the gas streams to protect downstream components such as turbine blades from erosion damage. It is expected that the filter elements in these systems will have to be made of ceramic materials to withstand goal service temperatures of 1600 F or higher.

  4. ADVANCED FLUE GAS CONDITIONING AS A RETROFIT UPGRADE TO ENHANCE PM COLLECTION FROM COAL-FIRED ELECTRIC UTILITY BOILERS

    SciTech Connect

    Kenneth E. Baldrey

    2003-02-01

    The U.S. Department of Energy and ADA Environmental Solutions are engaged in a project to develop commercial flue gas conditioning additives. The objective is to develop conditioning agents that can help improve particulate control performance of smaller or under-sized electrostatic precipitators on utility coal-fired boilers. The new chemicals will be used to control both the electrical resistivity and the adhesion or cohesivity of the fly ash. There is a need to provide cost-effective and safer alternatives to traditional flue gas conditioning with SO{sub 3} and ammonia. During this reporting quarter, two cohesivity-specific additive formulations, ADA-44C and ADA-51, were evaluated in a full-scale trial at the American Electric Power Conesville plant. Ammonia conditioning was also evaluated for comparison. ADA-51 and ammonia conditioning significantly reduced rapping and non-rapped particulate re-entrainment based on stack opacity monitor data. Based on the successful tests to date, ADA-51 will be evaluated in a long-term test.

  5. Control of NOx and particulate emissions from spreader-stokers fired with hogged wood

    SciTech Connect

    Munro, J.M.; Bradshaw, F.W.; Pershing, D.W.

    1987-06-01

    The formation and emission of nitrogen oxides and particulate carry-over were studied from spreader-stoker combustion of nogged Douglas-fir, with a focus on optimizing the combustion conditions in each of the two distinct combustion zones, the bed phase and the suspension phase. Local oxygen availability was the controlling parameter for nitric oxide formation. Minimum nitric oxide emissions were found when local air: fuel stoichiometric ratios were held at 0.70-0.85, with emissions reduced as much as 39%. Long first-stage residence times allowed intermediate nitrogenous species to decay to molecular nitrogen, if there was sufficient oxygen for first-stage formation of nitric oxide. Entrainment of large particulates was a function of furnace gas velocities in the bed zone. Operation of the furnace at low stoichiometric ratios (fuel rich) in the bed zone reduced these gas velocities and thus reduced particulate emissions. (Refs. 12).

  6. Experimental study on the influence of the porosity of parallel plate stack on the temperature decrease of a thermoacoustic refrigerator

    NASA Astrophysics Data System (ADS)

    Setiawan, Ikhsan; Bambang Setio Utomo, Agung; Mitrayana; Katsuta, Masafumi; Nohtomi, Makoto

    2013-04-01

    Thermoacoustic refrigerators are cooling devices which are environmentally friendly because they don't use hazardous gases like chlorofuorocarbons (CFCs) or hydrofuorocarbons (HFCs) but rather air or inert gases as working medium. They apply sound wave with high intensity to pump heat from the cold to hot the regions through a stack in a resonator tube. One of the important parameters of thermoacoustic refrigerators is the porosity (blockage ratio) of stack which is a fraction of cross sectional area of the resonator unblocked for the gas movement by the stack. This paper describes an experimental study on how the porosity of parallel plate stack affects the temperature decrease of a thermoacoustic refrigerator. The porosity of parallel plate stack is specified by the thickness of plates and the spacing between plates. We measured the maximum temperature decreases of thermacoustic refrigerator using stacks with various porosities in the range of 0.5 - 0.85, with plate spacing from 0.5 mm to 1.5 mm and plate thicknesses 0.3 mm, 0.4 mm, and 0.5 mm. The measurements were done with two resonators with length of 0.8 m and 1.0 m, with air at atmospheric pressure and room temperature, correspond to thermal penetration depths (??) of 0.26 mm and 0.29 mm, respectively. It was found that there is an optimum porosity which gives the largest temperature decreases, and there is a tendency that the optimum porosity shifts to a larger value and the temperature decrease become larger when we used a stack with thinner plates. On the other hand, the study on the dependence of the temperature decrease on the plate thickness and the plate spacing reveals more useful information than that on the stack porosity itself. We found that stack with thinner plates tends to give larger temperature decrease, and the plate spacing of around 4?? leads to the largest temperature decrease.

  7. TI-59 programmable calculator programs for in-stack opacity, venturi scrubbers, and electrostatic precipitators. User manual Jul 78-Jul 79

    SciTech Connect

    Cowen, S.J.; Ensor, D.S.; Sparks, L.E.

    1980-05-01

    The report explains the basic concepts of in-stack opacity as measured by in-stack opacity monitors. Also included are calculator programs that model the performance of venturi scrubbers and electrostatic precipitators. The effect of particulate control devices on in-stack opacity can be predicted by using these programs. The size distribution data input can be either in lognormal or histogram format. The opacity is calculated using Deirmendjian's approximation to Mie series to obtain extinction efficiencies. An alternative opacity program employing the exact Mie series solution is also described. The running time for this program is about 8 hours; that for the approximation program is 30 minutes. The accuracy of these programs is as good as the measured data input.

  8. Measurement of Particulate Pollutants in the Atmosphere

    NASA Technical Reports Server (NTRS)

    Ckuan, Raymond L.

    1971-01-01

    Representative measurements of the mass concentration of particulate matter in the atmosphere are presented, to demonstrate the application of a new type of instrument evolved from aerospace research to various types of particulate pollution and their dynamics. The instrument employs aerodynamic impaction of particles onto an adhesive-coated piezo-electric crystal whose resonant frequency decreases with mass accretion on its surface, with a resulting particulate mass resolution of 10(exp -11) gram. Applications include air basin with aerial measurement of particulate mass concentration, jet aircraft wake, stationary industrial sources, direct on-line measurement of automobile exhaust, and techniques for source detection.

  9. Powder and particulate production of metallic alloys

    NASA Technical Reports Server (NTRS)

    Grant, N. J.

    1982-01-01

    Developments of particulate metallurgy of alloyed materials where the final products is a fully dense body are discussed. Particulates are defined as powders, flakes, foils, silvers, ribbons and strip. Because rapid solidification is an important factor in particulate metallurgy, all of the particulates must have at least one dimension which is very fine, sometimes as fine as 10 to 50 microns, but move typically up to several hundred microns, provided that the dimension permits a minimum solidification rate of at least 100 K/s.

  10. Particulate residue separators for harvesting devices

    DOEpatents

    Hoskinson, Reed L.; Kenney, Kevin L.; Wright, Christopher T.; Hess, John R.

    2010-06-29

    A particulate residue separator and a method for separating a particulate residue stream may include a plenum borne by a harvesting device, and have a first, intake end and a second, exhaust end; first and second particulate residue air streams which are formed by the harvesting device and which travel, at least in part, along the plenum and in a direction of the second, exhaust end; and a baffle assembly which is located in partially occluding relation relative to the plenum, and which substantially separates the first and second particulate residue air streams.

  11. Methods of separating particulate residue streams

    DOEpatents

    Hoskinson, Reed L. (Rigby, ID); Kenney, Kevin L. (Idaho Falls, ID); Wright, Christopher T. (Idaho Falls, ID); Hess, J. Richard (Idaho Falls, ID)

    2011-04-05

    A particulate residue separator and a method for separating a particulate residue stream may include an air plenum borne by a harvesting device, and have a first, intake end and a second, exhaust end; first and second particulate residue air streams that are formed by the harvesting device and that travel, at least in part, along the air plenum and in a direction of the second, exhaust end; and a baffle assembly that is located in partially occluding relation relative to the air plenum and that substantially separates the first and second particulate residue air streams.

  12. Electrically heated particulate filter using catalyst striping

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J; Ament, Frank

    2013-07-16

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating is applied to the PF that increases a temperature of the combustion of the particulates within the PF.

  13. Electrically heated particulate filter embedded heater design

    DOEpatents

    Gonze, Eugene V.; Chapman, Mark R.

    2014-07-01

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine and wherein an upstream surface of the particulate filter includes machined grooves. A grid of electrically resistive material is inserted into the machined grooves of the exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF.

  14. 40 CFR 52.2347 - Stack height regulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Utah § 52.2347 Stack height regulations. The State of Utah has committed to revise its stack height...EPA's modified requirements. The State of Utah agrees to process appropriate...

  15. 40 CFR 52.2347 - Stack height regulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Utah § 52.2347 Stack height regulations. The State of Utah has committed to revise its stack height...EPA's modified requirements. The State of Utah agrees to process appropriate...

  16. 40 CFR 52.2347 - Stack height regulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Utah § 52.2347 Stack height regulations. The State of Utah has committed to revise its stack height...EPA's modified requirements. The State of Utah agrees to process appropriate...

  17. 40 CFR 52.2347 - Stack height regulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Utah § 52.2347 Stack height regulations. The State of Utah has committed to revise its stack height...EPA's modified requirements. The State of Utah agrees to process appropriate...

  18. 40 CFR 52.2347 - Stack height regulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Utah § 52.2347 Stack height regulations. The State of Utah has committed to revise its stack height...EPA's modified requirements. The State of Utah agrees to process appropriate...

  19. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...52.2633 Stack height regulations. In a letter dated December 9, 1988, to Douglas M. Skie, EPA, from Charles A. Collins, Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in accordance with...

  20. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...52.2633 Stack height regulations. In a letter dated December 9, 1988, to Douglas M. Skie, EPA, from Charles A. Collins, Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in accordance with...

  1. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...52.2633 Stack height regulations. In a letter dated December 9, 1988, to Douglas M. Skie, EPA, from Charles A. Collins, Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in accordance with...

  2. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...52.2633 Stack height regulations. In a letter dated December 9, 1988, to Douglas M. Skie, EPA, from Charles A. Collins, Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in accordance with...

  3. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...52.2633 Stack height regulations. In a letter dated December 9, 1988, to Douglas M. Skie, EPA, from Charles A. Collins, Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in accordance with...

  4. VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO THE FAR RIGHT. WAREHOUSE WITH ITS RIDGELINE ROTARY VENTS TO RIGHT OF STACK. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  5. 40 CFR 52.1832 - Stack height regulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...IMPLEMENTATION PLANS (CONTINUED) North Dakota § 52.1832 Stack height regulations. The State of North Dakota has committed to revise its stack...modified requirements. The State of North Dakota agrees to make the...

  6. 40 CFR 52.1832 - Stack height regulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...IMPLEMENTATION PLANS (CONTINUED) North Dakota § 52.1832 Stack height regulations. The State of North Dakota has committed to revise its stack...modified requirements. The State of North Dakota agrees to make the...

  7. 40 CFR 52.1832 - Stack height regulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...IMPLEMENTATION PLANS (CONTINUED) North Dakota § 52.1832 Stack height regulations. The State of North Dakota has committed to revise its stack...modified requirements. The State of North Dakota agrees to make the...

  8. 40 CFR 52.1832 - Stack height regulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...IMPLEMENTATION PLANS (CONTINUED) North Dakota § 52.1832 Stack height regulations. The State of North Dakota has committed to revise its stack...modified requirements. The State of North Dakota agrees to make the...

  9. 40 CFR 52.1832 - Stack height regulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...IMPLEMENTATION PLANS (CONTINUED) North Dakota § 52.1832 Stack height regulations. The State of North Dakota has committed to revise its stack...modified requirements. The State of North Dakota agrees to make the...

  10. Project W-420 Stack Monitoring system upgrades conceptual design report

    SciTech Connect

    TUCK, J.A.

    1998-11-06

    This document describes the scope, justification, conceptual design, and performance of Project W-420 stack monitoring system upgrades on six NESHAP-designated, Hanford Tank Farms ventilation exhaust stacks.

  11. 40 CFR 52.1388 - Stack height regulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...OF IMPLEMENTATION PLANS (CONTINUED) Montana § 52.1388 Stack height regulations. The State of Montana has committed to revise its stack height...EPA's modified requirements. The State of Montana agrees to make the appropriate...

  12. Diagnosis of PEMFC Stack Failures via Electrochemical Impedance Spectroscopy.

    E-print Network

    Victoria, University of

    i Diagnosis of PEMFC Stack Failures via Electrochemical Impedance Spectroscopy. by Walter Roberto on a PEMFC stack under real operating conditions. They are also the basis of ongoing research, development

  13. Measuring Particulate Emissions from Autos

    NSDL National Science Digital Library

    Willey, Babe

    This learning activity from the Advanced Technology Environmental and Energy Center (ATEEC) is intended to help environmental science or biology students connect a real-world problem to the application of math, science, technical and critical thinking knowledge and skill concepts; the lesson specifically focuses on particulate emissions from automobiles and their impact on air pollution. The activity should take about one class period to complete (plus time for students to complete analysis outside of class), and requires a few easily obtainable materials. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

  14. Investigation of the relationship between particulate-bound mercury and properties of fly ash in a full-scale 100 MWe pulverized coal combustion boiler

    SciTech Connect

    Sen Li; Chin-Min Cheng; Bobby Chen; Yan Cao; Jacob Vervynckt; Amanda Adebambo; Wei-Ping Pan [Western Kentucky University, Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology

    2007-12-15

    The properties of fly ash in coal-fired boilers influence the emission of mercury from power plants into the environment. In this study, seven different bituminous coals were burned in a full-scale 100 MWe pulverized coal combustion boiler and the derived fly ash samples were collected from a mechanical hopper (MH) and an electrostatic precipitator hopper (ESP). The mercury content, specific surface area (SSA), unburned carbon, and elemental composition of the fly ash samples were analyzed to evaluate the correlation between the concentration of particulate-bound mercury and the properties of coal and fly ash. For a given coal, it was found that the mercury content in the fly ash collected from the ESP was greater than in the fly ash samples collected from the MHP. This phenomenon may be due to a lower temperature of flue gas at the ESP (about 135{sup o}C) compared to the temperature at the air preheater (about 350{sup o}C). Also, a significantly lower SSA observed in MH ash might also contribute to the observation. A comparison of the fly ash samples generated from seven different coals using statistical methods indicates that the mercury adsorbed on ESP fly ashes has a highly positive correlation with the unburned carbon content, manganese content, and SSA of the fly ash. Sulfur content in coal showed a significant negative correlation with the Hg adsorption. Manganese in fly ash is believed to participate in oxidizing volatile elemental mercury (Hg{sup 0}) to ionic mercury (Hg{sup 2+}). The oxidized mercury in flue gas can form a complex with the fly ash and then get removed before the flue gas leaves the stack of the boiler.

  15. Method of making polymer powders and whiskers as well as particulate products of the method and atomizing apparatus

    DOEpatents

    Otaigbe, Joshua U. (Ames, IA); McAvoy, Jon M. (Moline, IL); Anderson, Iver E. (Ames, IA); Ting, Jason (Ames, IA); Mi, Jia (Pittsburgh, PA); Terpstra, Robert (Ames, IA)

    2001-01-09

    Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.

  16. 40 CFR 86.004-15 - NOX plus NMHC and particulate averaging, trading, and banking for heavy-duty engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Engines, and for 1985 and Later Model Year New Gasoline Fueled, Natural Gas-Fueled, Liquefied Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.004-15 NOX plus NMHC and particulate averaging, trading, and banking for...

  17. Wafer warpage analysis of stacked wafers for 3D integration

    Microsoft Academic Search

    Youngrae Kim; Sung-Keun Kang; Sung-Dong Kim; Sarah Eunkyung Kim

    The demand for wafer stacking technology has been increasing significantly. Although many technical challenges of wafer stacking have improved greatly, there are still many processing issues to be resolved. One of them is wafer warpage since it causes process and product failures such as delamination, cracking, mechanical stresses, and even electrical failure. In this study the warpage of multi-stacked wafers

  18. Take It From The Top: How Does This Stack Up?

    NSDL National Science Digital Library

    The Exploratorium

    2012-06-26

    In this activity, learners explore center of gravity, or balance point, of stacked blocks. Simple wooden blocks can be stacked so that the top block extends completely past the end of the bottom block, seemingly in a dramatic defiance of gravity. A mathematical pattern can be noted in the stacking.

  19. A simple machine simulator for teaching stack frames

    Microsoft Academic Search

    Dino Schweitzer; Jeff Boleng

    2010-01-01

    Stack frames are a fundamental concept in computer science often taught in an operating systems or an assembly language programming course. Computer security courses also rely on an understanding of stack frame concepts when teaching buffer overflow attacks. To assist students in learning the fundamentals of stack frames and related concepts, we have developed an interactive Simple Machine Simulator tool

  20. High-temperature deformation of alumina/yttria tetragonal zirconia polycrystals particulate composites and particulate laminates

    NASA Astrophysics Data System (ADS)

    Wang, Jue

    Al2O3/Y-TZP particulate composites consisting of 20--80 vol% Al2O3 and Al2O3/Y-TZP particulate laminates with varying composition and ratios of layer thickness were fabricated, respectively, by tapecasting, lamination, and sintering. The resulting particulate composites and particulate laminates were tested in compression and tension at 1300--1450°C over strain rates from 1.00 x 10-5 to 3.16 x 10-4 s-1. The high temperature behaviors of Al2O 3/Y-TZP particulate composites and particulate laminates were characterized under conditions in which changes to the microstructure during testing were deliberately minimized. Results show that stress exponents are approximately two for both particulate composites and particulate laminates when tested in compression and tension, consistent with a grain-boundary sliding mechanism. Particulate laminates are stronger than particulate composites with the same overall composition due to the constraint imposed by the hard layer on the soft layer during the deformation. This hard layer dominates the resistance to deformation of the particulate laminates. A limited number of elongation-to-failure tests were also conducted at 1350°C at a true strain rate of 1.00 x 10-4 s-1. Although grain growth and cavitaton occurred during the elongation-to-failure tests, superplasticity was observed for Al2O3/Y-TZP particulate composites and particulate laminates. In addition, models of composite creep behavior were compared to the experimental data. A constrained isostrain model was found to provide a good prediction for the high-temperature deformation of Al2O3/Y-TZP particulate composites and particulate laminates.