Science.gov

Sample records for particules par chute

  1. Mécanismes d'éjection de particules par laser impulsionnel

    NASA Astrophysics Data System (ADS)

    Grojo, D.; Cros, A.; Delaporte, Ph.; Sentis, M.; Dubus, H.; Mionetto, R.

    2006-12-01

    L'enlèvement de particules de dimensions nanométriques est l'un des principaux challenges à relever pour atteindre les futurs objectifs de l'industrie microélectronique. Les procédés laser présentent, dans certains cas, des performances très intéressantes, mais les mécanismes d'éjection des particules polluant la surface restent cependant fort mal connus. L'étude de la dynamique d'éjection des particules, par une technique optique, a mis en évidence l'existence de deux mécanismes dont l'importance relative dépend de la fluence d'irradiation. A forte fluence l'ablation locale du substrat sous la particule prédomine, alors que pour les fluences plus faibles le mécanisme semble être lié à l'enlèvement de l'humidité résiduelle à l'interface particule substrat. Contrairement aux modèles précédemment proposés, la contribution de la force d'inertie s'exerçant sur la particule lors de l'expansion thermique rapide des matériaux est négligeable.

  2. Lessons learned in stepped chute research

    USDA-ARS?s Scientific Manuscript database

    Early research on stepped chutes focused on steep gravity style stepped chutes. Today, the research trend has shifted to stepped chutes applied to more moderate slopes like those for aging embankment dams. Research contributions have been made on hydraulic properties of stepped chutes including ai...

  3. 30 CFR 57.9309 - Chute design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Chute design. 57.9309 Section 57.9309 Mineral....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons pulling chutes....

  4. Application de la transformation de Fourier fractionnaire à la restitution numérique des hologrammes des particules éclairées par un faisceau gaussien elliptique astigmate

    NASA Astrophysics Data System (ADS)

    Nicolas, F.; Coëtmellec, S.; Brunel, M.; Allano, D.; Lebrun, D.; Janssen, A. J. E. M.

    2006-10-01

    Cette étude concerne la diffraction d'un faisceau gaussien elliptique astigmate par une particule opaque. Nous montrons que la transformation de Fourier fractionnaire bidimensionnelle est un outil mathématique bien adapté à l'analyse des hologrammes des particules enregistrés par un tel faisceau.

  5. With drag chute deployed

    NASA Technical Reports Server (NTRS)

    1997-01-01

    KENNEDY SPACE CENTER, FLA. -- With drag chute deployed, the Space Shuttle Columbia hurtles down Runway 33 at KSC''';s Shuttle Landing Facility to conclude the Microgravity Science Laboratory-1 (MSL- 1) mission. With main gear touchdown at 2:33:11 p.m. EDT, April 8, the STS-83 mission duration was 3 days, 23 hours, 12 minutes. The planned 16-day mission was cut short by a faulty fuel cell. This is only the third time in Shuttle program history that an orbiter was brought home early due to a mechanical problem. This was also the 36th KSC landing since the program began in 1981. Mission Commander James D. Halsell, Jr. flew Columbia to a perfect landing with help from Pilot Susan L. Still. Other crew members are Payload Commander Janice E. Voss; Mission Specialists Michael L.Gernhardt and Donald A. Thomas; and Payload Specialists Roger K. Crouch and Gregory T. Linteris. In spite of the abbreviated flight, the crew was able to perform MSL-1 experiments. The Spacelab-module-based experiments were used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station and to conduct combustion, protein crystal growth and materials processing investigations.

  6. 30 CFR 56.9310 - Chute hazards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... tools to free material. (c) When broken rock or material is dumped into an empty chute, the chute shall be equipped with a guard or all persons shall be isolated from the hazard of flying rock or material. ...

  7. 30 CFR 56.9310 - Chute hazards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... tools to free material. (c) When broken rock or material is dumped into an empty chute, the chute shall be equipped with a guard or all persons shall be isolated from the hazard of flying rock or material. ...

  8. 30 CFR 57.9310 - Chute hazards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the proper tools to free material. (c) When broken rock or material is dumped into an empty chute, the chute shall be equipped with a guard or all persons shall be isolated from the hazard of flying rock or...

  9. 30 CFR 57.9310 - Chute hazards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the proper tools to free material. (c) When broken rock or material is dumped into an empty chute, the chute shall be equipped with a guard or all persons shall be isolated from the hazard of flying rock or...

  10. 30 CFR 57.9309 - Chute design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

  11. 30 CFR 57.9309 - Chute design.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

  12. 30 CFR 57.9309 - Chute design.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

  13. 30 CFR 57.9309 - Chute design.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

  14. Stepped chute training wall height requirements

    USDA-ARS?s Scientific Manuscript database

    Stepped chutes are commonly used for overtopping protection for embankment dams. Aerated flow is commonly associated with stepped chutes if the chute has sufficient length. The aeration and turbulence of the flow can create a significant amount of splash over the training wall if not appropriately...

  15. 30 CFR 56.9309 - Chute design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Chute design. 56.9309 Section 56.9309 Mineral... Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites § 56.9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

  16. Feeder for particulate material

    SciTech Connect

    Christofer, D.E.; Stock, A.J.

    1981-03-24

    Feeder apparatus for feeding at a controlled variable rate particulate solid material, such as coal, from a supply conduit located above a gravimetric feeder to a discharge chute located below the feeder. The particulate material flows to the feeder from the supply conduit along a path having a generally vertical center line and the discharge chute provides a flow path having a generally vertical center line closely laterally spaced relative to the center line of flow to the feeder. The feeder apparatus has a horizontally extending housing with an upwardly facing inlet through which the material flows to the feeder and a downwardly facing outlet forming part of the discharge chute through which the material flows from the feeder. Within the housing is a main feeder conveyor including an endless belt with a generally horizontal span adapted to receive at one end the particulate material flowing to the feeder and to convey in a layer a measured quantity of material a horizontal distance across weighing means to an exit zone at the opposite end of the belt, the horizontal distance being substantially greater than the spacing between the center lines of flow to the feeder and through such discharge chute. Associated with the main feeder conveyor is a gravimetric control system for controlling the amount of material deposited on the belt. Particulate material that drops off the main conveyor belt at the exit zone is received on a return belt conveyor and carried in a reverse direction a sufficient distance to bring the material to the discharge chute. Cooperation between the main feeder conveyor and the return conveyor permits gravimetric feeding of particulate material to the discharge chute that is closely laterally spaced to the flow path of material to the main conveyor by a distance that is substantially less than the length of travel of the material on the main conveyor.

  17. 30 CFR 56.9309 - Chute design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

  18. 30 CFR 56.9309 - Chute design.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

  19. 30 CFR 56.9309 - Chute design.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

  20. 30 CFR 56.9309 - Chute design.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

  1. 29 CFR 1926.852 - Chutes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (e) Any chute opening, into which workmen dump debris, shall be protected by a substantial guardrail approximately 42 inches above the floor or other surface on which the men stand to dump the material. Any space.... (g) Chutes shall be designed and constructed of such strength as to eliminate failure due to impact...

  2. 29 CFR 1926.852 - Chutes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (e) Any chute opening, into which workmen dump debris, shall be protected by a substantial guardrail approximately 42 inches above the floor or other surface on which the men stand to dump the material. Any space.... (g) Chutes shall be designed and constructed of such strength as to eliminate failure due to impact...

  3. 29 CFR 1926.852 - Chutes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (e) Any chute opening, into which workmen dump debris, shall be protected by a substantial guardrail approximately 42 inches above the floor or other surface on which the men stand to dump the material. Any space.... (g) Chutes shall be designed and constructed of such strength as to eliminate failure due to impact...

  4. 29 CFR 1926.852 - Chutes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... (e) Any chute opening, into which workmen dump debris, shall be protected by a substantial guardrail approximately 42 inches above the floor or other surface on which the men stand to dump the material. Any space.... (g) Chutes shall be designed and constructed of such strength as to eliminate failure due to impact...

  5. 29 CFR 1926.852 - Chutes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (e) Any chute opening, into which workmen dump debris, shall be protected by a substantial guardrail approximately 42 inches above the floor or other surface on which the men stand to dump the material. Any space.... (g) Chutes shall be designed and constructed of such strength as to eliminate failure due to impact...

  6. [Water chutes and traumatic tetraplegia].

    PubMed

    Falktoft, C; Biering-Sørensen, F

    1990-06-25

    Diving into shallow water is unfortunately a well known cause to spinal cord injury (SCI). This case history describes how a 23 year old man, who slid head first into a swimming pool with insufficient depth of water contracted cervical fractures and SCI with complete loss of motor function caudal to the C7 segment. Because this seems to represent a new cause of SCI, we advise the authorities to reassess the security regarding chute construction and the necessary water depth. Furthermore, warning signs and lifeguard supervision to prevent people from sliding head first when the water depth is insufficient should be mandatory.

  7. Access door for coal crusher feed chute

    SciTech Connect

    Cecil, T.W.; Shrum, D.B.; Smith, K.

    1992-04-14

    This patent describes a coal-crushing facility including a coal crusher, and a feed chute for conveying coal to the crusher. This patent describes improvement in door means comprising at least part of a top wall of the feed chute disposed for movement in response to accumulation of coal in the feed chute and wherein the coal acts directly on the door means with sufficient force to move the door means from a closed condition to at least a slightly open condition; and means responsive to movement of the door means to effect interruption of feeding coal to the crusher.

  8. Selectable towline spin chute system

    NASA Technical Reports Server (NTRS)

    Vairo, Daniel M. (Inventor); Whipple, Raymond D. (Inventor)

    1991-01-01

    An emergency spin recovery parachute is presented that is housed within a centrally mounted housing on the aft end of an aircraft and connected to a ring fitting within the housing. Two selectively latching shackles connected to separate towlines are openly disposed adjacent the ring fitting. The towlines extend in opposite directions from the housing along the aircraft wing to attachment points adjacent the wing-tips where the other end of each towline is secured. Upon pilot command, one of the open shackles latches to the ring fitting to attach the towline connected thereto, and a second command signal deploys the parachute. Suitable break-away straps secure the towlines to the aircraft surface until the parachute is deployed and the resulting force on the towline attached to the parachute overcomes the straps and permits the towline to extend to the point of attachment to exert sufficient drag on the spinning aircraft to permit the pilot to regain control of the aircraft. To employ the parachute as a drag chute to reduce landing speeds, both shackles and their respective towlines are latched to the ring fitting.

  9. 21. REMAINS OF HOP BAILING CHUTE ON SECOND FLOOR; THIS ...

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

    21. REMAINS OF HOP BAILING CHUTE ON SECOND FLOOR; THIS CHUTE EXTENDS TO THE GROUND FLOOR. - James W. Seavey Hop Driers, 0.6 mile East from junction of Highway 99 & Alexander Avenue, Corvallis, Benton County, OR

  10. 20. REMAINS OF HOP BAILING CHUTE ON GROUND FLOOR; THIS ...

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

    20. REMAINS OF HOP BAILING CHUTE ON GROUND FLOOR; THIS CHUTE EXTENDS TO THE SECOND FLOOR. - James W. Seavey Hop Driers, 0.6 mile East from junction of Highway 99 & Alexander Avenue, Corvallis, Benton County, OR

  11. Chute the Works. Motivating for Fitness and Movement.

    ERIC Educational Resources Information Center

    Carleton, Nancy L.

    1989-01-01

    Movement activities which utilize a rectangular chute are described. The chute, in addition to its motivational qualities, can be employed in several fitness areas--flexibility, muscular strength and endurance, and cardiorespiratory endurance. (IAH)

  12. Chute the Works. Motivating for Fitness and Movement.

    ERIC Educational Resources Information Center

    Carleton, Nancy L.

    1989-01-01

    Movement activities which utilize a rectangular chute are described. The chute, in addition to its motivational qualities, can be employed in several fitness areas--flexibility, muscular strength and endurance, and cardiorespiratory endurance. (IAH)

  13. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent displacement...

  14. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent displacement...

  15. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent displacement...

  16. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent displacement...

  17. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent displacement...

  18. Space Shuttle Orbiter Drag Chute Summary

    NASA Technical Reports Server (NTRS)

    Lowry, Charles H.

    2013-01-01

    This paper summarizes the development history and technical highlights of the Space Shuttle Orbiter Drag Chute Program. Data and references are given on the design, development, and testing of the system, plus several interesting operational issues and solutions. The last Shuttle flight was completed in 2011 and all the Orbiters have now become museum pieces. Before all the data from system development and the 86 Orbiter Drag Chute (ODC) operational landings is lost or forgotten, it may be useful to summarize it here and to identify data sources for future reference. Much has been written about various aspects of the program, and this summary has attempted to cite many such references to make available more detailed information. The ODC program was a high-visibility NASA program that afforded the opportunity to thoroughly engineer and test the chute system, far beyond so many of today s tight-budget programs. So the ODC program was extremely informative--it provided a wide scope of information including protective door jettison issues and solutions, wind tunnel data and analyses on chute stability and drag behind a huge and rather blunt forebody, component and system reuse, and chute cleaning methods. Technology and data created have aided several current and past parachute programs, and will continue to do so in the future. The original Orbiter preliminary design included a drag parachute-- it was deleted early to save weight. But after the 1987 Challenger accident and during the program redefinition phase that followed, Astronaut John Young presented a strong case for enhancing landing safety by adding nosegear steering, brake improvements, and reviving the drag chute.

  19. Webinar: Stepped chute design for embankment dams

    USDA-ARS?s Scientific Manuscript database

    Changing demographics in the vicinity of dams have led to hazard creep in a number of dams worldwide. Many of these dams now have insufficient spillway capacity as a result of these changes in hazard classification from low to significant or high hazard. Stepped chutes applied to the embankment da...

  20. Chutes and Ladders for the Impatient

    ERIC Educational Resources Information Center

    Cheteyan, Leslie A.; Hengeveld, Stewart; Jones, Michael A.

    2011-01-01

    In this paper, we review the rules and game board for "Chutes and Ladders", define a Markov chain to model the game regardless of the spinner range, and describe how properties of Markov chains are used to determine that an optimal spinner range of 15 minimizes the expected number of turns for a player to complete the game. Because the Markov…

  1. Sediment loads and transport at constructed chutes along the Missouri River - Upper Hamburg Chute near Nebraska City, Nebraska, and Kansas Chute near Peru, Nebraska

    USGS Publications Warehouse

    Densmore, Brenda K.; Rus, David L.; Moser, Matthew T.; Hall, Brent M.; Andersen, Michael J.

    2016-02-04

    Comparisons of concentrations and loads from EWI samples collected from different transects within a study site resulted in few significant differences, but comparisons are limited by small sample sizes and large within-transect variability. When comparing the Missouri River upstream transect to the chute inlet transect, similar results were determined in 2012 as were determined in 2008—the chute inlet affected the amount of sediment entering the chute from the main channel. In addition, the Kansas chute is potentially affecting the sediment concentration within the Missouri River main channel, but small sample size and construction activities within the chute limit the ability to fully understand either the effect of the chute in 2012 or the effect of the chute on the main channel during a year without construction. Finally, some differences in SSC were detected between the Missouri River upstream transects and the chute downstream transects; however, the effect of the chutes on the Missouri River main-channel sediment transport was difficult to isolate because of construction activities and sampling variability.

  2. Simplistic design methods for moderate-sloped stepped chutes

    USDA-ARS?s Scientific Manuscript database

    Numerous contributions have been made on the hydraulic properties of the air entrainment inception point and aerated flow region especially for steep, stepped chutes. Stepped chutes applied to aging embankment dams to address inadequate spillway capacity and to provide overtopping protection is a g...

  3. 15. DETAIL OF FRONT OF HEADFRAME AND STEEL DISCHARGE CHUTE ...

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

    15. DETAIL OF FRONT OF HEADFRAME AND STEEL DISCHARGE CHUTE LOCATED NEAR THE TOP OF THE HEADFRAME. PICTURED AT THE BOTTOM IS THE TIMBER-FRAMED CHUTE SLATED FOR REMOVAL BY THE DEPARTMENT OF STATE LANDS TO FACILITATE BULKHEADING OF SHAFT. VIEW LOOKING NORTH. - Butte Mineyards, Stewart Mine, Intersection of Main & Woolman Streets, Butte, Silver Bow County, MT

  4. Stilling the waters: Stilling basin design for stepped chutes

    USDA-ARS?s Scientific Manuscript database

    Energy dissipation is a desired feature of stepped chute design because it may lead to a shorter length of stilling basin than that of a traditional smooth chute design. Design parameters for stilling basins include Froude number, clear water flow depth, the sequent flow depth, and tailwater. Rese...

  5. 6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER ...

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

    6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER OF LEVEL4; ENTRAILS WERE DROPPED INTO CHUTE, THEN PASSED THROUGH THE FLOOR TO THE GUT SHANTY ON LEVEL 3 TO BE SORTED AND CLEANED - Rath Packing Company, Hog Dressing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  6. 12. Upstream view showing thelower log pond log chute in ...

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

    12. Upstream view showing thelower log pond log chute in the main channel of the Hudson River. The log chute in the dam can be seen in the background. Facing southwest. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  7. 116. Photocopied July 1978. (QMC) DRAWING OF 'SKIPGATE AND CHUTE'. ...

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

    116. Photocopied July 1978. (QMC) DRAWING OF 'SKIP-GATE AND CHUTE'. SHOWS CHUTE LEADING FROM UNDERGROUND STORAGE BIN AND THE MANNER OF DROPPING THE SKIP'S REAR WHEELS IN ORDER TO TIP THE MOUTH OF THE SKIP UP, SO THAT IT CAN BE FILLED TO CAPACITY MORE READILY. C. 1904. - Quincy Mining Company, Hancock, Houghton County, MI

  8. A guide to coal chute replacement

    SciTech Connect

    O'Neil, M.

    2006-11-15

    Good material flow can reduce coal yard maintenance and operational problems. A thorough inspection of the conveyor system can reveal some of the obvious signs of underperforming material transfer points in a power generation facility. The author gives 10 reasons why plant owners may need to look at an engineered transfer solution to improve flow, particularly of Powder River Basin coal. Items are ordered starting from auditing the inside of the chute walls, moving to liners, then to general buildup and outside spillage. 3 photos.

  9. STS-66 Edwards Landing with Drag Chute

    NASA Image and Video Library

    1994-11-14

    The space shuttle Atlantis lands with its drag chute deployed on runway 22 at Edwards, California, to complete the STS-66 mission dedicated to the third flight of the Atmospheric Laboratory for Applications and Science-3 (ATLAS-3), part of NASA's Mission to Planet Earth program. The astronauts also deployed and retrieved a free-flying satellite designed to study the middle and lower thermospheres and perform a series of experiments covering life sciences research and microgravity processing. The landing was at 7:34 a.m. (PST) 14 November 1994, after being waved off from the Kennedy Space Center, Florida, due to adverse weather.

  10. 32. Coffee bean sluiceway on ground floor showing chute bringing ...

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

    32. Coffee bean sluiceway on ground floor showing chute bringing beans from first floor hopper. HAER PR, 6-MAGU, 1B-17 - Hacienda Buena Vista, PR Route 10 (Ponce to Arecibo), Magueyes, Ponce Municipio, PR

  11. 8. SOUTHEAST SIDE OF PUMPING PLANT, TAILRACE, DISCHARGE CHUTE, AND ...

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

    8. SOUTHEAST SIDE OF PUMPING PLANT, TAILRACE, DISCHARGE CHUTE, AND BAFFLE CHAMBER - Outlook Irrigation District, Pumping Plant & Woodstave Pipe, Hudson Road & Snipes Lateral Road vicinity, Outlook, Yakima County, WA

  12. 3. VIEW OF WEST AND SOUTH FACADES, SHOWING CHUTES AND ...

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

    3. VIEW OF WEST AND SOUTH FACADES, SHOWING CHUTES AND PORTION OF SUPPORT STRUCTURE FOR OVERHEAD CONVEYOR, LOOKING NORTHEAST - Marvine Colliery, Dorr Thickener Plant No. 1, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  13. 26. FIRST LEVEL, VIEW OF TRANSFER CHUTES FROM BIN NUMBERS ...

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

    26. FIRST LEVEL, VIEW OF TRANSFER CHUTES FROM BIN NUMBERS 28 AND 32 LEADING TO OUT LEG; LOOKING SOUTHEAST - Northwestern Consolidated Elevator "A", 119 Fifth Avenue South, Minneapolis, Hennepin County, MN

  14. 1. Building 15 west elevation oblique showing coal conveyor, chute ...

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

    1. Building 15 west elevation oblique showing coal conveyor, chute and hopper. Coal feeds boiler in Building 3. View looking SE. - John & James Dobson Carpet Mill (West Parcel), Building No. 15, 4041-4055 Ridge Avenue, Philadelphia, Philadelphia County, PA

  15. Layered granule chute flow near the angle of repose

    SciTech Connect

    Pitts, J.H.; Walton, O.R.

    1985-03-29

    A natural, two-layered gravity flow of sand can be obtained on chutes inclined at angles slightly above the angle of repose of the sand. The top-surface layer is free-flowing, is thin, and moves rapidly at supercritical velocity. The velocity depends mainly on the character of the sand and the chute inclination angle. The bottom layer is thick and moves more slowly, with the flow controlled by adjustable weirs at the chute exit. The velocity profile in the thick bottom layer is curved; as much as an order of magnitude higher velocity occurs in the upper portion of the layer than occurs along the bottom wall of the chute. This study has applications to the cascade inertial fusion concept.

  16. DETAIL VIEW OF CUTTING ROOMS SHOWING CULLETT CHUTES FOR WASTE ...

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

    DETAIL VIEW OF CUTTING ROOMS SHOWING CULLETT CHUTES FOR WASTE GLASS, LOOKING EAST - Chambers Window Glass Company, Cutting Room, North of Drey (Nineteenth) Street, West of Constitution Boulevard, Arnold, Westmoreland County, PA

  17. 1. Mill exterior, high grade chute partially restored on the ...

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

    1. Mill exterior, high grade chute partially restored on the outside of mill building center of picture. Looking northeast from below bridge. - Kennecott Copper Corporation, Concentration Mill, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  18. 17. VIEW FROM OPERATOR DECK, SHOWING TRASH RACKS, CHUTES, AND ...

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

    17. VIEW FROM OPERATOR DECK, SHOWING TRASH RACKS, CHUTES, AND HEADGATE COVERS, LOOKING NORTH - Cabot Station Electric Generating Plant, Gantry Crane, Montague City Road, Turners Falls vicinity, Montague, Franklin County, MA

  19. 8. This metal chute in building #3 carried the cloth ...

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

    8. This metal chute in building #3 carried the cloth bags full of finished tire chains from upper floors to the warehouse on the first floor. - American Chain & Cable Company, East Princess Street (400 Block), York, York County, PA

  20. 23. LOWER END OF HIDE CHUTE, BASEMENT LEVEL; NOTE SORTING ...

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

    23. LOWER END OF HIDE CHUTE, BASEMENT LEVEL; NOTE SORTING TABLE AND HANDCART FOR MOVING HIDES - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  1. Criticality safety analysis of a calciner exit chute

    SciTech Connect

    Haught, C.F.; Basoglu, B.; Brewer, R.W.; Hollenback, D.F.; Wilkinson, A.D.; Dodds, H.L. . Nuclear Engineering Dept.); Oxenham, R.L. )

    1994-01-01

    Calcination of uranyl nitrate into uranium oxide is part of normal operations of some enrichment plants. Typically, a calciner discharges uranium oxide powder (U[sub 3]O[sub 8]) into an exit chute that directs the powder into a receiving can located in a glove box. One possible scenario for a criticality accident is the exit chute becoming blocked with powder near its discharge. The blockage restricts the flow of powder causing the exit chute to become filled with the powder. If blockage does occur, the height of the powder could reach a level that would not be safe from a criticality point of view. In this analysis, the subcritical height limit is examined for 98% enriched U[sub 3]O[sub 8] in the exit chute with full water reflection and optimal water moderation. The height limit for ensuring criticality safety during such an accumulation is 28.2 cm above the top of the discharge pipe at the bottom of the chute. Chute design variations are also evaluated with full water reflection and optimal water moderation. Subcritical configurations for the exit chute variation are developed, but the configurations are not safe when combined with the calciner. To ensure criticality safety, modifications must be made to the calciner tube or safety measures must be implemented if these designs are to be utilized with 98% enriched material. A geometrically safe configuration for the exit chute is developed for a blockage of 20% enriched powder with full water reflection and optimal water moderation, and this configuration is safe when combined with the existing calciner.

  2. 10. DETAIL OF CONDEMNED MATERIAL CHUTE IN NORTHWEST CORNER OF ...

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

    10. DETAIL OF CONDEMNED MATERIAL CHUTE IN NORTHWEST CORNER OF 4TH LEVEL; GOVERNMENT INSPECTORS COULD CONDEMN DISEASED OR CONTAMINATED CARCASSES AT ANY POINT DURING THE DISASSEMBLY PROCESS; CONDEMNED MATERIAL WAS 'SIDETRACKED,' WEIGHED, AND DROPPED THROUGH THE CHUTE INTO A HUGE CHOPPER ON LEVEL 3; NOTE SCALE ON OVERHEAD CONVEYOR RAIL - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  3. STS-70 landing drag chute deploy

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Space Shuttle orbiter Discovery deploys its drag chute after a smooth touchdown on KSC's Runway 33, marking a successful conclusion to the STS-70 mission. Discovery landed on orbit 143, during the second opportunity of the day. Main gear touchdown was unofficially listed at 8:02 a.m. EDT on July 22, 1995. The orbiter traveled some 3.7 million statute miles during the nearly nine-day flight, which included a one-day extension because of fog and low visibility conditions at the KSC Shuttle Landing Facility on July 21. STS-70 was the 24th landing at KSC and the 70th Space Shuttle mission. The five-member crew deployed a Tracking and Data Relay Satellite-G (TDRS-G). Crew members were Commander Terence 'Tom' Henricks, Pilot Kevin R. Kregel, and Mission Specialists Nancy Jane Currie, Donald A. Thomas and Mary Ellen Weber. STS-70 also was the maiden flight of the new Block I orbiter main engine, which flew in the number one position. The other two engines were of the existing Phase II design.

  4. Physical habitat dynamics in four side-channel chutes, lower Missouri River

    USGS Publications Warehouse

    Jacobson, Robert B.; Johnson, Harold E.; Laustrup, Mark S.; D'Urso, Gary J.; Reuter, Joanna M.

    2004-01-01

    Construction of the side-channel chutes has become a popular means to rehabilitate habitate of the Lower Missouri River. We studied various aspects of hydrology, hydraulics, and geomorphology of four side-channel chutes to document a range of existing conditions in the Lower Missouri River. The Cranberry Bend side-channel chute has existed for at least 40 years and is an example of a persistent, minimally engineered chute. The Lisbon Bottom side-channel chute is a young chute, created by extreme floods during 1993-1996, and allowed to evolve with minimum engineering of inlet and outlet structures. The Hamburg Bend and North Overton Bottom side-channel chutes were constructed in 1996 and 2000, respectively, as part of the Missouri River Bank Stabilization and navigation Fish and Wildlife Mitigation Project. These side-channel chutes provide increased areas of sandbars and shallow, slow water -- habitats thought to be substantially diminished in the modern Missouri River. Depths and velocities measured in side-channel chutes are also present in the main channel, but the chutes provide more areas of slow, shallow water and they increase the range of discharges over which shallow, slow water is present. The 3.6 km long Lisbon Bottom chute provides as much as 50% of the entire shallow water habitat that exists in the encompassing 15 km reach of the river. At Cranberry Bend and Lisbon Bottom, the side-channel chutes provided 10-40% of the availabile sandbar area in the reach, depending on discharge. Each of the side-channel chutes shows evidence of continuing erosion and deposition. The longevity and the Cranberry Bend chute attests to dynamic stability -- that is, a chute that maintains form and processes while shifting in position. The Hamburg chute similarly shows evidence of lateral movement and construction of flood plain to compensate for erosion. The Lisbon Bottom chute -- the most intensively studied chute -- appears to have achieved an equilibrium width and

  5. Estimated splash and training wall height requirements for stepped chutes applied to embankment dams

    USDA-ARS?s Scientific Manuscript database

    Aging embankment dams are commonly plagued with insufficient spillway capacity. To provide increased spillway capacity, stepped chutes are frequently applied as an overtopping protection system for embankment dams. Stepped chutes with sufficient length develops aerated flow. The aeration and flow...

  6. DETAIL VIEW OF ORE CHARGING CHUTES OF THE UPPER TRAM ...

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

    DETAIL VIEW OF ORE CHARGING CHUTES OF THE UPPER TRAM TERMINAL,LOOKING NORTHWEST TOWARD THE REAR OF THE STRUCTURE. THE ELECTRIC DRIVE MOTOR IS IN THE BACKGROUND AT UPPER RIGHT JUST BEHIND THE DRIVE GEAR. THE BELT FROM THIS MOTOR CONNECTED TO THE WHEEL AT TOP CENTER,WHICH DROVE THE SMALLER GEAR MESHED WITH THE LARGER ONE. THERE ARE NO CONTROL DOORS FOR THESE CHUTES OTHER THAN THE METAL ONES IN THE FOREGROUND. SEE CA-291-51 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  7. DETAIL VIEW OF ORE CHARGING CHUTES OF THE UPPER TRAM ...

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

    DETAIL VIEW OF ORE CHARGING CHUTES OF THE UPPER TRAM TERMINAL, LOOKING NORTHWEST TOWARD THE REAR OF THE STRUCTURE. THE ELECTRIC DRIVE MOTOR IS IN THE BACKGROUND AT UPPER RIGHT JUST BEHIND THE DRIVE GEAR. THE BELT FROM THIS MOTOR CONNECTED TO THE WHEEL AT TOP CENTER, WHICH DROVE THE SMALLER GEAR MESHED WITH THE LARGER ONE. THERE ARE NO CONTROL DOORS FOR THESE CHUTES OTHER THAN THE METAL ONES IN THE FOREGROUND. SEE CA-291-35 FOR IDENTICAL B&W NEGATIVE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  8. Design, fabrication and testing of a low headroom conveyor transfer chute. Final technical report. [Chutes for transferring material from one conveyor to another

    SciTech Connect

    Douglas, S. B.; Larson, P.

    1980-12-01

    This document contains the results of tests performed on eight one-sixth scale models of low headroom transfer chutes for underground belt conveyors. The models were evaluated using a methodology technique to select one chute for further full-scale testing in an underground mine. The study concludes that the slide chute should be tested in an underground 90/sup 0/ transfer point. The report contains a state-of-the-art survey, a literature search, data from mine visits, test results, evaluation based on the methodology technique, and a set of guidelines for the design of low headroom transfer chutes. Also included are the preliminary designs of the slide and stone box chutes, scaled up from the designs used in the tests. Following the first phase of the program, the contract was terminated for the convenience of the government; therefore, the program did not progress to the Phase II full-scale chute fabrication or Phase III field testing.

  9. 2. DETAIL OF DISCHARGE CHUTES FROM VOGT AUTOMATIC TUBE ICE ...

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

    2. DETAIL OF DISCHARGE CHUTES FROM VOGT AUTOMATIC TUBE ICE MACHINE IN SOUTHWEST CORNER OF LEVEL 5; ICE DROPPED INTO HOLDING BIN BEFORE BEING TRANSFERRED TO RAIL CARS OUTSIDE BUILDING (HENRY VOGT MACHINE COMPANY, LOUISVILLE, USA, PATENT NO. 2,200,424 - Rath Packing Company, Cooler Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  10. 13. DETAIL OF TWOWAY CHUTE AT END OF VISCERA TABLE; ...

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

    13. DETAIL OF TWO-WAY CHUTE AT END OF VISCERA TABLE; HINGED FLAP AT CENTER OF OPENING DISTRIBUTED EDIBLE AND INEDIBLE OFFAL TO APPROPRIATE PROCESSING AREAS ON LEVEL 3 - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  11. 1. VIEW OF EMPIRE MINE AREA WITH TAILINGS, ORE CHUTE, ...

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

    1. VIEW OF EMPIRE MINE AREA WITH TAILINGS, ORE CHUTE, AND COLLAPSED BUILDINGS VISIBLE, AND BARE SWITCHBACK HILLSIDE FROM WHICH #4, #5 AND #6 WERE MADE. CAMERA IS POINTED NORTHWEST. - Florida Mountain Mining Sites, Empire State Mine, West side of Florida Mountain, Silver City, Owyhee County, ID

  12. Looking southwest at the chute leading from the coal elevator ...

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

    Looking southwest at the chute leading from the coal elevator to the conveyor belt feeding the coal storage hopper on the floor below. - Wheeling-Pittsburgh Steel Corporation, Allenport Works, Boiler House, Route 88 on West bank of Monongahela River, Allenport, Washington County, PA

  13. Studies of granular flow down an inclined chute

    SciTech Connect

    Hanes, D.M.

    1992-01-01

    A preliminary series of experiments were run in order to examine the effects sidewalls have on the steady-state mass flow rate of granular material in a rectangular, inclined chute. These experiments also serve to assess the problems associated with the initial operation of the granular flow apparatus. Presumably, the friction between the sidewalls and the flowing material will slow the flow rate of that material. The relative effect of the sidewalls should decrease with increasing width for a given flow entrance condition. For instance, when the width of the chute is at a minimum (one grain diameter), the sidewalls will have a maximum frictional effect. And as the width approaches infinity, the sidewalls will have a minimum frictional effect. It is desired to know at what chute widths the sidewall effects will reasonably approach this minimum, if this condition can even be approached with the existing apparatus. The relationship between chute width and flow rate will be important to know during more involved experiments which will follow this initial investigation. These experiments will include the measurement of localized grain density, local velocity and individual grain dynamics (rotation and translation) and collisions. The secondary objective, to observe and correct problems with the system, is a more general and qualitative goal.

  14. 15. VIEW OF DISCHARGE THROUGH SPILLWAY CHUTE FROM WEST RETAINING ...

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

    15. VIEW OF DISCHARGE THROUGH SPILLWAY CHUTE FROM WEST RETAINING WALL, FACING SOUTH. STANDING WAVES ARE VISIBLE. WATER ELEVATION MEASURED 4.8 FEET ABOVE CREST. December 1933 - Cushman No. 1 Hydroelectric Power Plant, Spillway, North Fork of Skokomish River, 5 miles West of Hood Canal, Hoodsport, Mason County, WA

  15. Studies of granular flow down an inclined chute

    SciTech Connect

    Hanes, D.M.

    1992-01-01

    The driving force for the granular flow in the experimental region is gravity. The vehicle which re-circulates this flow is an 46 cm Corra-Trough belt conveyor manufactured by Buck-El, Inc. A drawing of this conveyor is shown in Figure 3. Entrance and exit chambers were designed to route the flow between the chute and the conveyor. Both devices had to be flexible because the position of the chute relative to the conveyor changes each time the angle of the chute is changed. Finally, to control the entering flow more accurately, an adjustable gate apparatus was constructed. The first step in setting up the chute is angle adjustment. The granular material used in the experiments described in this report are technical quality glass spheres, three millimeters in diameter. These beads are produced by Cataphote, Inc. Cataphote lists the tolerances for the 3mm spheres at [plus minus]0.2 mm. The average mass of a single bead was measured to be 0.034 g which gives an average measured specific gravity of the glass at 2.42 g/cm[sup 3].

  16. La pelade par plaques

    PubMed Central

    Spano, Frank; Donovan, Jeff C.

    2015-01-01

    Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre les schémas thérapeutiques et les résultats des traitements pour la pelade par plaques, de même que les aider à identifier les patients pour qui une demande de consultation en dermatologie pourrait s’imposer. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant le traitement de la pelade par plaques. Message principal La pelade par plaques est une forme auto-immune de perte pileuse qui touche à la fois les enfants et les adultes. Même s’il n’y a pas de mortalité associée à la maladie, la morbidité découlant des effets psychologiques de la perte des cheveux peut être dévastatrice. Lorsque la pelade par plaques et le sous-type de la maladie sont identifiés, un schéma thérapeutique approprié peut être amorcé pour aider à arrêter la chute des cheveux et possiblement faire commencer la repousse. Les traitements de première intention sont la triamcinolone intralésionnelle avec des corticostéroïdes topiques ou du minoxidil ou les 2. Les médecins de famille peuvent prescrire ces traitements en toute sécurité et amorcer ces thérapies. Les cas plus avancés ou réfractaires pourraient avoir besoin de diphénylcyclopropénone topique ou d’anthraline topique. On peut traiter la perte de cils avec des analogues de la prostaglandine. Les personnes ayant subi une perte de cheveux abondante peuvent recourir à des options de camouflage ou à des prothèses capillaires. Il est important de surveiller les troubles psychiatriques en raison des effets psychologiques profonds de la perte de cheveux. Conclusion Les médecins de famille verront de nombreux patients qui perdent leurs cheveux. La reconnaissance de la pelade par plaques et la compréhension du processus pathologique sous-jacent permettent d’amorcer un schéma thérapeutique approprié. Les cas plus graves ou r

  17. Hydrographic surveys at seven chutes and three backwaters on the Missouri River in Nebraska, Iowa, and Missouri, 2011-13

    USGS Publications Warehouse

    Krahulik, Justin R.; Densmore, Brenda K.; Anderson, Kayla J.; Kavan, Cory L.

    2015-01-01

    Discharge was measured at chute survey sites, in both the main channel of the Missouri River upstream from the chute and the chute. Many chute entrances and control structures were damaged by floodwater during the 2011 Missouri River flood, allowing a larger percentage of the total Missouri River discharge to flow through the chute than originally intended in the chute design. Measured discharge split between the main channel and the chute at most chutes was consistent with effects of the 2011 Missouri River flood damages and a larger percent of the total Missouri River discharge was flowing through the chute than originally intended. The U.S. Army Corps of Engineers repaired many of these chutes in 2012 and 2013, and the resulting hydraulic changes are reflected in the discharge splits.

  18. Distributor means for charging particulate material into receptacles

    DOEpatents

    Greaves, Melvin J.

    1977-06-14

    Disclosed are receptacles, such as shaft furnaces illustrated by a blast furnace and an upright oil shale retort, embodying rotatable charge distributor means for distributing particulate charge material in the furnace, which charge distributor means can provide a high uniformity of distribution of various sizes of particles and also can provide and maintain a stock line of desired contour and heighth in the receptacle. The distributor means includes a hopper having rigidly fixed to it a plurality of downwardly extending chutes with lower discharge portions that discharge in concentric circular zones at the stock line. The distributor means includes a segmented portion at the juncture of the hopper and the chutes that divides the charge material discharged into the hopper in proportion to the area of the circular zone at the stock line that is fed by the chute. The distributor means embodies means for providing mass flow of the particulate charge material through the chutes to the stock line and for avoiding segregation between larger and smaller particles of charge material deposited at the stock line.

  19. STS-66 Edwards Landing with Drag Chute

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Atlantis lands with its drag chute deployed on runway 22 at Edwards, California, to complete the STS-66 mission dedicated to the third flight of the Atmospheric Laboratory for Applications and Science-3 (ATLAS-3), part of NASA's Mission to Planet Earth program. The astronauts also deployed and retrieved a free-flying satellite designed to study the middle and lower thermospheres and perform a series of experiments covering life sciences research and microgravity processing. The landing was at 7:34 a.m. (PST) 14 November 1994, after being waved off from the Kennedy Space Center, Florida, due to adverse weather. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to

  20. Weathering processes implied from analysis of small Martian avalanche chutes

    NASA Technical Reports Server (NTRS)

    Sullivan, R.

    1992-01-01

    It has been proposed that the smaller features of martian spur and gully slope morphology, located along the upper walls of Valles Marineris, are avalanche chutes. A three-dimensional stability back-analysis technique was developed and applied to these small avalanche chutes, yielding average values of cohesion and angle of internal friction for the mobile layer materials on these slopes at the time of each slope failure. Generally, the analysis showed that at the time of each slope failure material strengths had been reduced to those of moderately cohesive debris down through depths of tens of meters. These results have implications and possible constraints for the nature and rate of martian weathering processes.

  1. Weathering processes implied from analysis of small Martian avalanche chutes

    NASA Technical Reports Server (NTRS)

    Sullivan, R.

    1992-01-01

    It has been proposed that the smaller features of martian spur and gully slope morphology, located along the upper walls of Valles Marineris, are avalanche chutes. A three-dimensional stability back-analysis technique was developed and applied to these small avalanche chutes, yielding average values of cohesion and angle of internal friction for the mobile layer materials on these slopes at the time of each slope failure. Generally, the analysis showed that at the time of each slope failure material strengths had been reduced to those of moderately cohesive debris down through depths of tens of meters. These results have implications and possible constraints for the nature and rate of martian weathering processes.

  2. Safety assessment of discharge chute isolation barrier preparation and installation

    SciTech Connect

    Meichle, R.H.

    1994-09-29

    The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparison of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions were made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classification.

  3. Advanced transfer chute reduces dust at lower cost

    SciTech Connect

    Blazek, C.

    2005-10-01

    Dominion Resources' Kincaid Generating Station in Illinois is recognized as a leader in handling and burning PRB coal. Since being named the Powder Plant of the Year in 2001 and 2004 by the PRB Coal Users' Group, Kincaid has improved its coal handling by installing an InteliFlo controlled-flow transfer chute from Benetech. The InteliFlo design eliminates the need for skirt boards, conveyor discharge hoods, and complex load bed designs, and reduces O & M costs. 4 figs.

  4. The geomorphic evolution of slopes and sediment chutes on forereefs

    NASA Astrophysics Data System (ADS)

    Hall, Douglas B.

    1999-03-01

    Frequent slope failures of the forereef dropoff occur in living coral reefs on the island of Bonaire in the southern Caribbean. Topographic profiles of ten sites were taken perpendicular to shore, followed by an estimation of coral ages ( M. annularis) along the topographic profiles. The coral ages were estimated from published rates of growth and sizes of the sampled corals. Comparisons of coral age and adjacent slope angle indicated that the steeper slopes are older and that mass failure of the slope reduces the steepness of the forereef front and destroys the coral community along the disturbed slope. Slopes grow until reaching a critical steepness, after which underwater sliding of the over-steepened forereef front results. In observed slides, the mechanical weakness in the reef structure that facilitates a slide failure was the result of a weak mud and coral rubble layer deposited 2 m below the living coral cover. The remaining slide scarp evolves into a sediment chute that conveys the resulting flow of biogenic sands from the shallow forereef terrace down the forereef edge. Because of the constant flow of sand down these channels, no corals can recolonize the sediment chutes and the chutes become stable topographic features. In addition, these indentations in the forereef front also serve as channels for the vertical density mixing of water of varying salinities and temperatures.

  5. Evaluation of structural issues related to isolation of the 100-KE/100-KW discharge chute

    SciTech Connect

    Winkel, B.V.; Hyde, L.L.

    1995-03-10

    The issue of excessive post-seismic leakage in the discharge chute of the K East and K West fuel storage basins was resolved by designing isolation barriers to maintain basin water levels if the discharge chute should drain. This report addresses the structural issues associated with isolation of the discharge chute. The report demonstrates the structural adequacy of the components associated with chute isolation for normal and seismic loading. Associated issues, such as hardware drop accidents and seismic slosh heights are also addressed.

  6. AFTI/F-16 Spin chute close-up

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A close-up photo of the spin chute mounted on the rear fuselage of the AFTI F-16, a safety device designed to prevent the loss of aircraft in spin conditions. Under some circumstances, pilots cannot recover from spins using normal controls. It these instances, the spin chute is deployed, thus 'breaking' the spin and enabling the pilot to recover. The spin chute is held in a metal cylinder attached to the AFTI F-16 by four tubes, a structure strong enough to withstand the shock of the spin chute opening. Unlike the air probe in the last photo, spin chutes are not standard equipment on research or prototype aircraft but are commonly attached expressly for actual spin tests. During the 1980s and 1990s, NASA and the U.S. Air Force participated in a joint program to integrate and demonstrate new avionics technologies to improve close air support capabilities in next-generation aircraft. The testbed aircraft, seen here in flight over the desert at NASA's Dryden Flight Research Center, Edwards, California, was called the Advanced Fighter Technology Integration (AFTI) F-16. The tests demonstrated technologies to improve navigation and the pilot's ability to find and destroy enemy ground targets day or night, including adverse weather. The aircraft--an F-16A Fighting Falcon (Serial #75-0750)--underwent numerous modifications. A relatively low-cost testbed, it evaluated the feasability of advanced, intergrated-sensor, avionics, and flight control technologies. During the first phase of the AFTI/F-16 program, which began in 1983, the aircraft demonstrated voice-actuated commands, helmet-mounted sights, flat turns, and selective fuselage pointing using forward-mounted canards and a triplex digital flight control computer system. The second phase of research, which began in the summer of 1991, demonstrated advanced technologies and capabilities to find and destroy ground targets day or night, and in adverse weather while using maneuverability and speed at low altitude. This

  7. Factors associated with marine injuries during vertical chute evacuation training.

    PubMed

    Harwood, Daniel; Farrow, Alexandra

    2008-09-01

    The use of a vertical chute marine evacuation system (MES) is now established on marine vessels; this system has, however, been associated with injuries during training. To identify risk factors associated with adverse outcomes during vertical chute MES training and to generate hypotheses for research into reducing injuries. Cross-sectional questionnaire study of a cohort of trainees attending vertical chute MES training courses, at two naval training establishments in 2005. Incident data were also collected from both training establishments and from Marine Accident Investigation Branch (MAIB) records. The response rate was 99% (n = 351). Pearson chi square and relative risks (RRs) were calculated for specific outcomes with a number of independent variables. Logistic regression was used to analyse independent variables with a statistically significant (P < 0.05) chi square for the outcome of 'suffering an injury' during training. Injury was associated with body mass index denoting 'overweight', 'obese' or 'morbidly obese' with an odds ratio (OR) of 12.7 (95% CI: 2.2-72.7). Participants below the mean height also had increased risk of suffering an injury during training (OR: 4.8; 95% CI: 1.2-18.5). Phobias and apprehension prior to training increased the risk of injury; reporting of 'some concern over the dark' was statistically significant (OR: 16.6; 95% CI: 1.6-171.5). Life jacket discomfort was also significantly associated with suffering an injury. Policy implications include alteration of the MES design and management of risk through training and informed decision making for choosing an evacuation system for ships and ferries.

  8. Criticality safety analysis and design modifications of a calciner exit chute

    SciTech Connect

    Haught, C.F.; Basoglu, B.; Brewer, R.W.; Hollenbach, D.F.; Wilkinson, A.D.; Dodds, H.L. Jr. ); D'Aquila, D. )

    1992-01-01

    Calcination of uranium solutions into uranium oxide is part of the normal operations of many plants in the uranium fuel cycle. A calciner discharges uranium oxide powder into an exit chute, which directs the flow of powder into a receiving container. An illustration of an existing exit chute is provided. One possible scenario for a criticality accident begins with a discharge pipe that is blocked with powder. If this scenario does occur, the powder in the chute can reach a height that would make the system critical. This work analyzes the effect of the accumulation of powder on the safety of the exit chute and calciner with a full water reflector present. The powder is also assumed to be optimally moderated to account for possible water ingress into the exit chute. The chemical form of the uranium oxide during this hypothetical accident is assumed to be U{sub 3}O{sub 8}.

  9. Fluvial processes and passive rehabilitation of the Lisbon Bottom side-channel chute, Lower Missouri River

    USGS Publications Warehouse

    Jacobson, Robert B.; Laustrup, Mark S.; Chapman, Michael D.

    2001-01-01

    Multiple large floods in 1993-1997 on the Lower Missouri River carved a side-channel chute through the river bottom at Lisbon, Missouri. Although similar in some respects to engineered side-channel chutes designed for habitat rehabilitation projects, the Lisbon Bottom chute has been unique in that it was allowed to evolve for more than four years with minimal stabilization. During the wet years, 1996-1999, the chute was subjected to abnormally high discharges and passed as much as 20% of the total discharge of the Missouri River. Relatively unrestrained fluvial processes during this time created a wide channel with highly diverse habitats. The upper one-half of the chute established a shallow, braided channel morphology similar to the pre-managed Missouri River. The lower half established a dynamically migrating, single-thread channel, and an incipient flood plain. Compared to the adjacent navigation channel, the chute established substantial areas of shallow, slow-velocity aquatic habitat that is considered to be in short supply in the present-day Lower Missouri River. The shortterm biological benefits have been mixed: the chute has fewer waterbird and benthic macroinvertebrate taxa than adjacent riverine habitats, but greater numbers of fish species compared to the navigation channel.

  10. X-29 Number Two in Flight Closeup of Spin Chute Mechanism

    NASA Image and Video Library

    1989-06-27

    Because the number two X-29 at NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center) flew at higher angles of attack than the number one aircraft, it required a spin chute system for safety. The system deployed a parachute for recovery of the aircraft if it inadvertently entered an uncontrolled spin. Most of the components of the spin chute system were located on a truss at the aft end of the aircraft. In addition, there were several cockpit modifications to facilitate use of the chute. The parachute was made of nylon and was of the conical ribbon type.

  11. Safety assessment of discharge chute isolation barrier preparation and installation

    SciTech Connect

    Meichle, R.H.

    1994-10-21

    This analysis examines activities associated with the installation of isolation barriers in the K Basins at the Hanford Reservation. This revision adds evaluation of barrier drops on stored fuel and basin floor, identifies fuel which will be moved and addresses criticality issues with sludge. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparisons of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions was made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classifications.

  12. STS-58 Landing at Edwards with Drag Chute

    NASA Image and Video Library

    1993-11-01

    A drag chute slows the space shuttle Columbia as it rolls to a perfect landing concluding NASA's longest mission at that time, STS-58, at the Ames-Dryden Flight Research Facility (later redesignated the Dryden Flight Research Center), Edwards, California, with a 8:06 a.m. (PST) touchdown 1 November 1993 on Edward's concrete runway 22. The planned 14 day mission, which began with a launch from Kennedy Space Center, Florida, at 7:53 a.m. (PDT), October 18, was the second spacelab flight dedicated to life sciences research. Seven Columbia crewmembers performed a series of experiments to gain more knowledge on how the human body adapts to the weightless environment of space. Crewmembers on this flight included: John Blaha, commander; Rick Searfoss, pilot; payload commander Rhea Seddon; mission specialists Bill MacArthur, David Wolf, and Shannon Lucid; and payload specialist Martin Fettman.

  13. 4. EMPIRE STATE MINE TAILINGS, ORE CHUTE/BIN, COLLAPSED BUILDING FROM ...

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

    4. EMPIRE STATE MINE TAILINGS, ORE CHUTE/BIN, COLLAPSED BUILDING FROM BELOW. CAMERA POINTED NORTHEAST. - Florida Mountain Mining Sites, Empire State Mine, West side of Florida Mountain, Silver City, Owyhee County, ID

  14. Flow, Morphology and Sedimentology of an Evolving Chute Cutoff on the Wabash River, IL-in.

    NASA Astrophysics Data System (ADS)

    Zinger, J. A.; Best, J.; Rhoads, B. L.; Larson, T. H.

    2014-12-01

    The development of chute cutoffs and the resulting abandonment of meander bends have a substantial influence on the sedimentary dynamics of floodplains. The incision of a chute cutoff channel can rapidly mobilize a large volume of floodplain sediment. On the other hand, bar formation during bend abandonment and the subsequent deposition of sediment within the oxbow lake are key processes in the production of a heterogeneous floodplain sedimentary architecture. This paper describes the evolution of two recent chute cutoffs on the Wabash River, IL-IN. We follow these cutoffs from their initial incision in 2008-2009 through the early stages of bend abandonment. The volume of floodplain sediment mobilized by erosion of the two cutoff channels is estimated using channel bankline positions determined from RTK-GPS surveys and aerial orthophotographs; this flux is then assessed within the context of the sediment mobilized by lateral migration of bends. Repeat bathymetric surveys and aerial photography capture the evolution of bar forms associated with the chute cutoff, and data from ground-penetrating radar reveal the subsurface structure of the complex assemblage of bars that developed as the chute cutoff system shifted from a predominantly erosional to a mixed depositional-erosional phase. These results are combined with knowledge of chute cutoff hydrodynamics to develop an understanding of the dynamics of sediment exchange between river channels and floodplains at evolving meander bend cutoffs.

  15. STS-85 Discovery Landing at KSC's SLF (drag chute release)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With drag chute deployed, the Space Shuttle orbiter Discovery touches down on Runway 33 at KSCs Shuttle Landing Facility at 7:07:59 a.m. EDT Aug. 19 to complete the 11-day, 20-hour and 27- minute-long STS-85 mission. At the controls are Commander Curtis L. Brown, Jr. and Pilot Kent V. Rominger. The first landing opportunity on Aug. 18 was waved off due to the potential for ground fog. Also onboard the orbiter are Payload Commander N. Jan Davis, Mission Specialist Robert L. Curbeam, Jr., Mission Specialist Stephen K. Robinson and Payload Specialist Bjarni V. Tryggvason. During the 86th Space Shuttle mission, the crew deployed the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere- Shuttle Pallet Satellite-2 (CRISTA-SPAS-2) free- flyer to conduct research on the Earths middle atmosphere, retrieving it on flight day 9. The crew also conducted investigations with the Manipulator Flight Demonstration (MFD), Technology Applications and Science-1 (TAS-1) and International Extreme Ultraviolet Hitchhiker-2 (IEH-2) experiments. Robinson also made observations of the comet Hale-Bopp with the Southwest Ultraviolet Imaging System (SWIS) while other members of the crew conducted biological experiments in the orbiters crew cabin. This was the 39th landing at KSC in the history of the Space Shuttle program and the 11th touchdown for Discovery at the space center.

  16. STS-94 Columbia Landing at KSC (drag chute deployed)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With its drag chute deployed, the Space Shuttle Orbiter Columbia touches down on Runway 33 at KSCs Shuttle Landing Facility at 6:46:34 a.m. EDT with Mission Commander James D. Halsell Jr. and Pilot Susan L. Still at the controls to complete the STS-94 mission. Also on board are Mission Specialist Donald A. Thomas, Mission Specialist Michael L. Gernhardt , Payload Commander Janice Voss, and Payload Specialists Roger K. Crouch and Gregory T. Linteris. Mission elapsed time for STS-94 was 15 days,16 hours, 44 seconds. During the Microgravity Science Laboratory-1 (MSL-1) mission, the Spacelab module was used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station while the flight crew conducted combustion, protein crystal growth and materials processing experiments. This mission was a reflight of the STS-83 mission that lifted off from KSC in April of this year. That space flight was cut short due to indications of a faulty fuel cell. This was Columbias 11th landing at KSC and the 38th landing at the space center in the history of the Shuttle program.

  17. Characterization of base roughness for granular chute flows.

    PubMed

    Jing, L; Kwok, C Y; Leung, Y F; Sobral, Y D

    2016-11-01

    Base roughness plays an important role in the dynamics of granular flows but is still poorly understood due to the difficulty of its quantification. For a bumpy base made of spheres, at least two factors should be considered in order to characterize its geometric roughness, namely, the size ratio of flow to base particles and the packing arrangement of base particles. In this paper, we propose an alternative definition of base roughness, R_{a}, as a function of both the size ratio and the distribution of base particles. This definition is generalized for random and regular packings of multilayered spheres. The range of possible values of R_{a} is presented, and optimal arrangements for maximizing base roughness are studied. Our definition is applied to granular chute flows in both two- and three-dimensional configurations, and is shown to successfully predict whether slip occurs at the base. A transition is observed from slip to nonslip conditions as R_{a} increases. Critical values of R_{a} are identified for the construction of a nonslip base at various angles of inclination.

  18. STS-49 Landing at Edwards with First Drag Chute Landing

    NASA Image and Video Library

    1992-05-16

    The Space Shuttle Endeavour concludes mission STS-49 at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, with a 1:57 p.m. (PDT) landing 16 May on Edward's concrete runway 22. The planned 7-day mission, which began with a launch from Kennedy Space Center, Florida, at 4:41 p.m. (PFT), 7 May, was extended two days to allow extra time to rescue the Intelsat VI satellite and complete Space Station assembly techniques originally planned. After a perfect rendezvous in orbit and numerous attempts to grab the satellite, space walking astronauts Pierre Thuot, Rick Hieb and Tom Akers successfully rescued it by hand on the third space walk with the support of mission specialists Kathy Thornton and Bruce Melnick. The three astronauts, on a record space walk, took hold of the satellite and directed it to the shuttle where a booster motor was attached to launch it to its proper orbit. Commander Dan Brandenstein and Pilot Kevin Chilton brought Endeavours's record setting maiden voyage to a perfect landing at Edwards AFB with the first deployment of a drag chute on a shuttle mission.

  19. STS-49 Landing at Edwards with First Drag Chute Landing

    NASA Image and Video Library

    1992-05-16

    The Space Shuttle Endeavour concludes mission STS-49 at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, with a 1:57 p.m. (PDT) landing May 16 on Edward's concrete runway 22. The planned 7-day mission, which began with a launch from Kennedy Space Center, Florida, at 4:41 p.m. (PFT), 7 May, was extended two days to allow extra time to rescue the Intelsat VI satellite and complete Space Station assembly techniques originally planned. After a perfect rendezvous in orbit and numerous attempts to grab the satellite, space walking astronauts Pierre Thuot, Rick Hieb and Tom Akers successfully rescued it by hand on the third space walk with the support of mission specialists Kathy Thornton and Bruce Melnick. The three astronauts, on a record space walk, took hold of the satellite and directed it to the shuttle where a booster motor was attached to launch it to its proper orbit. Commander Dan Brandenstein and Pilot Kevin Chilton brought Endeavours's record setting maiden voyage to a perfect landing at Edwards with the first deployment of a drag chute on a shuttle mission.

  20. STS-94 Columbia Landing at KSC (drag chute deployed)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With its drag chute deployed, the Space Shuttle Orbiter Columbia touches down on Runway 33 at KSCs Shuttle Landing Facility at 6:46:34 a.m. EDT with Mission Commander James D. Halsell Jr. and Pilot Susan L. Still at the controls to complete the STS-94 mission. Also on board are Mission Specialist Donald A. Thomas, Mission Specialist Michael L. Gernhardt , Payload Commander Janice Voss, and Payload Specialists Roger K. Crouch and Gregory T. Linteris. Mission elapsed time for STS-94 was 15 days,16 hours, 44 seconds. During the Microgravity Science Laboratory-1 (MSL-1) mission, the Spacelab module was used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station while the flight crew conducted combustion, protein crystal growth and materials processing experiments. This mission was a reflight of the STS-83 mission that lifted off from KSC in April of this year. That space flight was cut short due to indications of a faulty fuel cell. This was Columbias 11th landing at KSC and the 38th landing at the space center in the history of the Shuttle program.

  1. Flood duration and chute cutoff formation in a wandering gravel-bed river

    NASA Astrophysics Data System (ADS)

    Sawyer, A.; Wilcox, A. C.

    2015-12-01

    Chute cutoffs occur when a bypass or "chute" channel incises across a bar or low floodplain area, re-distributing water and sediment. Cutoffs result from a setup and a triggering event, typically during overbank flow, but the combined effect of magnitude and duration on potential erosion in in-channel and overbank areas is still poorly constrained. Here we investigated how overbank flow duration impacts cutoff formation and spatiotemporal shear stress patterns in a wandering gravel-bed river. We applied a two-dimensional hydraulic model to a recently reconstructed reach of the Clark Fork River in western Montana that experienced chute cutoffs during a long-duration flood in 2011. Hydrographs with increasing durations exceeding overbank were simulated; for each magnitude-duration combination, various metrics were quantified for in-channel and overbank areas separately. We confirm the hypothesized importance of floodplain elevation, vegetation presence, chute-channel inlet entrance location, and high overbank shear stress zones at bend apexes on cutoff occurrence. Floodplain width plays an important role in controlling unit discharge such that overbank areas are more competent in a narrower floodplain conveyance corridor. Duration controls cumulative flow exceeding sediment mobility thresholds, having the largest effect in overbank areas. Side channels at the reconstructed study site act like naturally formed incipient chutes. This work describes a complex floodplain system characteristic of wandering gravel-bed rivers with implications for understanding morphodynamic evolution, river restoration, and flow management in regulated rivers.

  2. Mediative adjustment of river dynamics: The role of chute channels in tropical sand-bed meandering rivers

    NASA Astrophysics Data System (ADS)

    Grenfell, M. C.; Nicholas, A. P.; Aalto, R.

    2014-03-01

    This paper examines processes of chute channel formation in four tropical sand-bed meandering rivers; the Strickland and Ok Tedi in Papua New Guinea, the Beni in Bolivia, and the lower Paraguay on the Paraguay/Argentina border. Empirical planform analyses highlight an association between meander bend widening and chute initiation that is consistent with recent physics-based modelling work. GIS analyses indicate that bend widening may be driven by a variety of mechanisms, including scour and cutbank bench formation at sharply-curving bends, point bar erosion due to cutbank impingement against cohesive terrace material, rapid cutbank erosion at rapidly extending bends, and spontaneous mid-channel bar formation. Chute channel initiation is observed to be predominantly associated with two of these widening mechanisms; i) an imbalance between cutbank erosion and point bar deposition associated with rapid bend extension, and ii) bank erosion forced by spontaneous mid-channel bar development. The work extends previous empirical analyses, which highlighted the role of bend extension (elongation) in driving chute initiation, with the observation that the frequency of chute initiation increases once bend extension rates and/or widening ratios exceed a reach-scale threshold. A temporal pattern of increased chute initiation frequency on the Ok Tedi, in response to channel steepening and mid-channel bar development following the addition of mine tailings, mirrors the inter- and intra-reach spatial patterns of chute initiation frequency on the Paraguay, Strickland and Beni Rivers, where increased stream power and sediment load are associated with increased bend extension and chute initiation rates. The process of chute formation is shown to be rate-dependent, and the threshold values of bend extension and widening ratio for chute initiation are shown to scale with measures of river energy, reminiscent of slope-ratio thresholds in river avulsion. Furthermore, Delft3D simulations

  3. Probes into the Actuality of Fantasy: Jean Epstein's "La Chute de la Maison Usher."

    ERIC Educational Resources Information Center

    Harpole, Charles H.

    "La Chute de la Maison Usher" is a film adaptation by Jean Epstein of two stories by Edgar Allan Poe, "The Fall of the House of Usher" and "The Oval Portrait." This film was typical of Epstein's artistic preoccupation with the ambivalence of reality as expressed in fantasy or surrealism, in qualities of movement, and…

  4. Breed group effects for chute exit velocity as an indicator trait for temperament in weaner cattle

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to determine breed group differences in chute exit velocity (CEV) in weaner cattle (n=3176). Data were collected in 2004 through 2008 under procedures of objective 3, Southern Regional Research project S1013 with the following states contributing data: FL, LA, and MS...

  5. Behavioral training and hydraulic chute restraint enables handling of eland antelope (Taurotragus oryx) without general anesthesia.

    PubMed

    Wirtu, Gemechu; Cole, Alexander; Pope, C Earle; Short, Charles R; Godke, Robert A; Dresser, Betsy L

    2005-03-01

    Difficulties and risks associated with restraining large nondomestic ungulates are limiting factors toward developing and applying assisted reproductive technologies, such as artificial insemination and embryo transfer. In this study on 10 female eland (Taurotragus oryx), we evaluated the use of behavioral training and handling handling in a hydraulic chute to perform transvaginal ultrasound-guided oocyte retrieval and other clinical procedures. Nine females were conditioned to associate specific sound cues with food treats. The interval from the audio cue until acceptance of handheld treats varied among females (1.8-58.3 min). Animals also differed in their response to training for voluntary entry into the chute. Handling eland for oocyte retrieval in the hydraulic chute required xylazine sedation. During sedation and handling, eland undergoing oocyte retrieval procedures had higher blood glucose levels (14.4 +/- 3.1) than females handled similarly but without oocyte retrieval (9.3 +/- 2.7 mmol/L). Plasma osmotic pressure, hematocrit, and creatine phosphokinase activity were similar between these two groups. Females that were more difficult to train had higher blood glucose levels than the more cooperative animals. Cooperative females had fewer vertical stripes on their sides. More than 40 procedures were conducted without complications or mortality. The combination of behavioral conditioning-training and restraint of sedated eland in a hydraulic chute was a reliable and repeatable method for performing minimally invasive assisted reproductive techniques.

  6. 29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Chute and hopper openings which present a hazard shall be guarded to prevent employees from falling... until the employee has left the bin. (j) Bin top openings that present a hazard to employees shall be... equipment to be used. The inspection shall include at least the eye bolts, wires, and sheaves. (2) Power...

  7. 29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Chute and hopper openings which present a hazard shall be guarded to prevent employees from falling... until the employee has left the bin. (j) Bin top openings that present a hazard to employees shall be... equipment to be used. The inspection shall include at least the eye bolts, wires, and sheaves. (2) Power...

  8. 29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.49...) Chute and hopper openings which present a hazard shall be guarded to prevent employees from falling... until the employee has left the bin. (j) Bin top openings that present a hazard to employees shall...

  9. Characteristics of suspended and streambed sediment within constructed chutes and the main channel at Upper Hamburg and Glovers Point Bends, Missouri River, Nebraska, 2008

    USGS Publications Warehouse

    Woodward, Brenda K.; Rus, David L.

    2011-01-01

    The U.S. Army Corps of Engineers, Omaha District, as part of the Missouri River Bank Stabilization and Navigation Mitigation Project, has constructed 17 off-channel chutes along the channelized Missouri River, downstream from Sioux City, Iowa, to increase habitat diversity. To better understand characteristics of suspended and streambed sediment within these constructed chutes, the U.S. Geological Survey investigated specific aspects of chute design and function in relation to sediment characteristics including: (1) effects of inlet structures; (2) changes occurring between the inlet and the outlet of a chute; (3) effects of chutes on sediment characteristics in the main channel; and (4) differences in chute dynamics between sampled chutes. Two chutes differing in design, location, and dynamics were studied, Upper Hamburg Bend near Nebraska City, Nebr., and Glovers Point Bend near Winnebago, Nebr. Each site was characterized using five or more sampling transects (two in the chute and three to four in the main channel) designed to bracket sediment exchanges between chutes and the main channel. A sixth transect was included at the Upper Hamburg Bend study site to account for the effects of a nontarget chute having its inlet midway between the inlet and outlet of the primary chute. Representative samples of suspended and streambed sediment were collected at each transect, along with measurements of turbidity and streamflow, between June and November 2008. Four sets of samples were collected at the Glovers Point Bend study site and five sample sets were collected from the Upper Hamburg Bend study site. Results from paired t-tests and standard t-tests indicated that the inlet structure design, passing inflow only from the top of the main-channel water column, reduced the supply of coarse-grained suspended sediment entering the chutes. Statistical comparisons did not indicate differences between the inlet and outlet of either chute; however, anecdotal evidence of recent

  10. Characteristics of Hydraulic Shock Waves in an Inclined Chute Contraction by Using Three Dimensional Numerical Model

    NASA Astrophysics Data System (ADS)

    Hsiao, Kai-Wen; Hsu, Yu-Chao; Jan, Chyan-Deng; Su, Yu-Wen

    2016-04-01

    The inclined rectangular chute construction is a common structure used in hydraulic engineering for typical reasons such as the increase of bottom slope, the transition from side channel intakes to tunnel spillways, the drainage construction, and the reduction of chute width due to bridges, flood diversion structures or irrigation systems. The converging vertical sidewalls of a chute contraction deflect the supercritical flow to form hydraulic shock waves. Hydraulic shock waves have narrow and locally extreme wavy surfaces, which commonly results in the requirement of higher height of sidewalls. Therefore, predicting the possible height and position of maximum hydraulic shock wave are necessary to design the required height of sidewalls to prevent flow overtopping. In this study, we used a three-dimensional computation fluid dynamics model (i.e., FLOW-3D) to simulate the characteristics of hydraulic shock waves in an inclined chute contraction. For this purpose, the parameters of simulated hydraulic shock wave, such as the shock angle, maximum shock wave height and maximum shock wave position in various conditions are compared with those calculated by the empirical relations obtained from literatures. We showed that the simulated results are extremely close to the experimental results. The numerical results validated the applicability of these empirical relations and extend their applicability to higher approach Froude numbers from 3.51 to 7.27. Furthermore, we also applied the Yuan-Shan-Tsu flood diversion channel under 200-year peak flow condition to FLOW-3D model to simulate the hydraulic shock waves and validate the effect of the installation of a diversion pier in the channel on promoting the stability of flow fluid. The results revealed that a diversion pier installed in the Yuan-Shan-Tsu flood diversion channel is helpful for improving the stability of flow field. In summary, this study demonstrates that FLOW-3D model can be used to simulate the

  11. Quantifying flood duration controls on chute cutoff formation in a wandering gravel-bed river

    NASA Astrophysics Data System (ADS)

    Sawyer, A.; Wilcox, A. C.

    2014-12-01

    Chute cutoffs, which occur when a bypass or "chute" channel incises across a point or braid bar, distribute water and sediment, regulate sinuosity, and create off-channel habitat in wandering gravel-bed rivers. Cutoffs have been hypothesized to occur by progressive migration preparing a bend for cutoff, after which overbank flow events provide a trigger to excavate new channels. This trigger may depend on the magnitude and duration of floods and their associated sediment fluxes. Here we investigated how overbank flow duration impacts cutoff formation in a wandering gravel-bed river. To explore this, we applied a two-dimensional hydrodynamic model to a recently reconstructed reach of the Clark Fork River in western Montana that experienced chute cutoffs during a long-duration flood event in 2011. Hydrographs exceeding bankfull and with varying durations were simulated to constrain the role of overbank flow duration on erosional work in chute cutoff channels. For each magnitude-frequency-duration combination, cumulative excess shear stress (i.e., above the threshold of sediment mobilization) was quantified for in-channel and overbank areas. Locations of shear stress divergence associated with morphological change were identified along chute pathways. Preliminary results suggest that overbank areas containing concentrated flowpaths such as swales follow cumulative excess shear stress curve patterns similar to in-channel areas. This work describes a dynamic system characteristic of wandering gravel-bed rivers in the Pacific Northwest, and has implications for understanding morphodynamic evolution, river restoration targeting off-channel habitat for fish, and geomorphic flow regime management in regulated rivers.

  12. Simulation of flow and evaluation of bridge scour at Horse Island Chute Bridge near Chester, Illinois

    USGS Publications Warehouse

    Huizinga, Richard J.; Rydlund, Jr., Paul H.

    2001-01-01

    The evaluation of scour at bridges throughout the State of Missouri has been ongoing since 1991, and most of these evaluations have used one-dimensional hydraulic analysis and application of conventional scour depth equations. Occasionally, the conditions of a site dictate that a more thorough hydraulic assessment is required. To provide the hydraulic parameters required to determine the potential scour depths at the bridge over Horse Island Chute near Chester, Illinois, a two-dimensional finite-element surface-water model (FESWMS-2DH) was used to simulate flood flows in the vicinity of the Missouri State Highway 51 crossing of the Mississippi River and Horse Island Chute. The model was calibrated using flood-flow information collected during the 1993 flood. A flood profile along the Illinois side of the Mississippi River on August 5, 1993, with a corresponding measured discharge of 944,000 cubic feet per second was used to calibrate the model. Two additional flood-flow simulations were run: the flood peak that occurred on August 6, 1993, with a maximum discharge of 1,000,000 cubic feet per second, and the discharge that caused impending overtopping of the road embankment in the vicinity of the Horse Island Chute bridge, with a discharge of 894,000 cubic feet per second (impendent discharge). Hydraulic flow parameters obtained from the simulations were applied to scour depth equations to determine general contraction and local pier and abutment scour depths at the Horse Island Chute bridge. The measured discharge of 944,000 cubic feet per second resulted in 13.3 feet of total combined contraction and local pier scour at Horse Island Chute bridge. The maximum discharge of 1,000,000 cubic feet per second resulted in 15.8 feet of total scour and the impendent discharge of 894,000 cubic feet per second resulted in 11.6 feet of total scour.

  13. Hydraulic and geomorphic processes in an overbank flood along a gravel-bed, meandering river: implications for chute formation

    NASA Astrophysics Data System (ADS)

    Harrison, L.; Dunne, T.; Fisher, G. B.

    2014-12-01

    Hydraulic interactions between rivers and floodplains produce off-channel chutes, whose presence can increase the ecological diversity of the valley floor. Detailed studies of the hydrologic exchanges between channels and floodplains are usually conducted in laboratory facilities, and studies documenting chute development are generally limited to qualitative observations. In this study, we use a reconstructed, gravel-bedded, meandering river as a laboratory for studying these mechanisms at field scale. Using an integrated field and modeling approach, we quantified the flow exchanges between the river channel and its floodplain during an overbank flood, and identified locations where flow had the capacity to erode floodplain chutes. Hydraulic measurements and modeling indicated high rates of flow exchange between the channel and floodplain, with flow rapidly decelerating as water was decanted from the channel onto the floodplain due to the frictional drag provided by substrate and riparian vegetation. Peak shear stresses were greatest downstream of the maxima in bend curvature, along the concave bank, where terrestrial LiDAR scans indicate initial floodplain chute formation. A second chute has developed across the convex bank of a meander bend, in a location where sediment accretion, point bar development and plant colonization have created divergent flow paths between the main channel and floodplain. In both cases, the off-channel chutes are evolving slowly during infrequent floods due to the coarse nature of the floodplain, though rapid chute formation would be more likely in finer-grained floodplains. The controls on chute formation at these locations include the river curvature, cross-stream position of the high velocity core, erodibility of the floodplain sediment, and the density of riparian vegetation.

  14. STS-49 Landing at Edwards with First Drag Chute Landing

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Shuttle Endeavour concludes mission STS-49 at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, with a 1:57 p.m. (PDT) landing 16 May on Edward's concrete runway 22. The planned 7-day mission, which began with a launch from Kennedy Space Center, Florida, at 4:41 p.m. (PFT), 7 May, was extended two days to allow extra time to rescue the Intelsat VI satellite and complete Space Station assembly techniques originally planned. After a perfect rendezvous in orbit and numerous attempts to grab the satellite, space walking astronauts Pierre Thuot, Rick Hieb and Tom Akers successfully rescued it by hand on the third space walk with the support of mission specialists Kathy Thornton and Bruce Melnick. The three astronauts, on a record space walk, took hold of the satellite and directed it to the shuttle where a booster motor was attached to launch it to its proper orbit. Commander Dan Brandenstein and Pilot Kevin Chilton brought Endeavours's record setting maiden voyage to a perfect landing at Edwards AFB with the first deployment of a drag chute on a shuttle mission. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their

  15. STS-58 Landing at Edwards with Drag Chute

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A drag chute slows the space shuttle Columbia as it rolls to a perfect landing concluding NASA's longest mission at that time, STS-58, at the Ames-Dryden Flight Research Facility (later redesignated the Dryden Flight Research Center), Edwards, California, with a 8:06 a.m. (PST) touchdown 1 November 1993 on Edward's concrete runway 22. The planned 14 day mission, which began with a launch from Kennedy Space Center, Florida, at 7:53 a.m. (PDT), October 18, was the second spacelab flight dedicated to life sciences research. Seven Columbia crewmembers performed a series of experiments to gain more knowledge on how the human body adapts to the weightless environment of space. Crewmembers on this flight included: John Blaha, commander; Rick Searfoss, pilot; payload commander Rhea Seddon; mission specialists Bill MacArthur, David Wolf, and Shannon Lucid; and payload specialist Martin Fettman. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space

  16. STS-49 Landing at Edwards with First Drag Chute Landing

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Shuttle Endeavour concludes mission STS-49 at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, with a 1:57 p.m. (PDT) landing May 16 on Edward's concrete runway 22. The planned 7-day mission, which began with a launch from Kennedy Space Center, Florida, at 4:41 p.m. (PFT), 7 May, was extended two days to allow extra time to rescue the Intelsat VI satellite and complete Space Station assembly techniques originally planned. After a perfect rendezvous in orbit and numerous attempts to grab the satellite, space walking astronauts Pierre Thuot, Rick Hieb and Tom Akers successfully rescued it by hand on the third space walk with the support of mission specialists Kathy Thornton and Bruce Melnick. The three astronauts, on a record space walk, took hold of the satellite and directed it to the shuttle where a booster motor was attached to launch it to its proper orbit. Commander Dan Brandenstein and Pilot Kevin Chilton brought Endeavours's record setting maiden voyage to a perfect landing at Edwards with the first deployment of a drag chute on a shuttle mission. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their

  17. Astronaut candidate Koichi Wakata gets assistance with his parachute following a simulated chute

    NASA Technical Reports Server (NTRS)

    1992-01-01

    1992 ASCAN TRAINING --- Astronaut candidate Koichi Wakata gets assistance with his parachute following a simulated chute drop at Vance Air Force Base. Wakata, representing the National Space Development Agency (NASDA) of Japan, is one of seven international mission specialist candidates who joined 19 United States astronaut candidates for the three-day parachute/survival training school at the Oklahoma Base.EDITORS NOTE: Since this photograph was taken, Wakata has been named as mission specialist for the STS-72 mission.

  18. An Innovative Magnetic Charging Chute to Improve Productivity of Sinter Machine at Rourkela Steel Plant

    NASA Astrophysics Data System (ADS)

    Selvam, Sambandham Thirumalai; Chaudhuri, Subhasis; Das, Arunaba; Singh, Mithilesh Kumar; Mahanta, H. K.

    Sintering is a process in sinter machine for agglomeration of iron ore and other raw material fines into a compact porous mass, i.e., sinter, used in Blast Furnaces as an iron bearing input charge material for hot metal production. 'Permeability' of sinter-bed on sinter machine i.e., the porosity in sinter-bed of charged materials, facilitates atmospheric air passes from the top to bottom across the depth of sinter-bed, when suction created from the bottom of the bed, for efficient heat carry over from top to bottom of the bed for complete burning of charged materials for effective sintering process controls the productivity of the sinter machine. The level of 'permeability' in sinter-bed is depending upon the effectiveness of 'charging chute' in size-wise 'segregation' of charge materials across the depth in sinter-bed, achieved due to differences in the sliding velocities of particles during charging into the moving sinter-bed. The permeability achieved by the earlier conventional 'charging chute' was limited due to its design and positional constraints in sinter machine. Improving the productivity of sinter machine, through increased permeability of sinter bed is successfully achieved through implementation of an innovatively designed and developed, "Magnetic Charging Chute" at Sinter Plant no. 2 of Rourkela Steel Plant. The induced magnetic force on the charged materials while the charge materials dropping down through the charge chute has improved the permeability of sinter bed through an unique method of segregating the para-magnetic materials and the finer materials of the charge materials to top layer of sinter bed along with improved size-wise segregation of charge materials. This has increased the productivity of the sinter machine by 3% and also reduced the solid fuel consumption i.e., coke breeze in input charge materials by 1 kg/t of sinter.

  19. Flow Structure and Channel Change in Chute Cutoffs On Meandering Rivers

    NASA Astrophysics Data System (ADS)

    Zinger, J. A.; Rhoads, B. L.; Best, J. L.; Johnson, K. K.

    2011-12-01

    Freely meandering rivers typically exhibit complex, continuously evolving patterns of planform geometry involving elongation of the channel path through lateral migration and shorting of this path through bend cutoffs. Despite the importance of cutoffs in shaping the planform geometry of meandering rivers, the fluvial processes operative immediately after initiation of a cutoff are poorly understood. Two recent chute cutoff events on a single bend on the Wabash River, IL-IN, have provided an unprecedented opportunity to document the morphologic evolution and flow structure of chute cutoffs in a large, unregulated, meandering river. Here, we present results of ADCP measurements of three-dimensional flow velocity and bed topography at these cutoffs and describe a conceptual model for the morphodynamics of chute cutoffs prior to oxbow lake formation. Our results indicate that the flow structure at upstream and downstream ends of cutoff channels, prior to plugging of the entrance and exit of the abandoned bend with sediment, is analogous to flow through diffluence - confluence units. The interaction of this flow structure with an erodible bed and banks can cause rapid widening of the upstream end of the cutoff channel and bar development i) in the main channel where velocities are reduced, and ii) in the separation zone of the cutoff channel. Over time, these patterns of deposition and erosion will lead formation of an oxbow lake and complete capture of the flow by the cutoff channel.

  20. Chute cutoff as a morphological response to stream reconstruction: The possible role of backwater

    NASA Astrophysics Data System (ADS)

    Eekhout, J. P. C.; Hoitink, A. J. F.

    2015-05-01

    Stream restoration efforts often aim at creating new unconstrained meandering channels without weirs and bank revetments. In reconstructed streams, the initial morphological response of the new streams is often rapid, until a dynamic equilibrium is reached. Here we report on a chute cutoff that occurred within 3 months after realization of a stream restoration project, caused by a plug bar that formed in response to a backwater effect. The temporal evolution of the morphology of both the new and the old channels was monitored over a period of nearly 8 months, including precutoff conditions. The observations can be separated into three stages. Stage 1 is the initial period leading to cutoff vulnerability, stage 2 is the actual cutoff, and stage 3 is the morphological adjustment in response to the cutoff. In stage 1, a plug bar was deposited in one of the channel bends. Hydrodynamic model results show the location of the plug bar coincides with a region where bed shear stress decreased in downstream direction due to backwater. Longitudinal channel bed profiles show that the channel slope decreased soon after channel reconstruction. Hence, sediment from upstream was available to form the plug bar. After the plug bar was deposited, an embayment formed in the floodplain at a location where the former channel was located (stage 2). The former channel was filled with sediment prior to channel construction. It is likely that the sediment at this location was less consolidated, and therefore, prone to erosion. The chute channel continued to incise and widen into the floodplain and, after 6 months, acted as the main channel, conveying the discharge during the majority of time (stage 3). The cutoff channel gradually continued to fill with sediment, from the moment the plug bar formed until the chute channel incised into the floodplain. Sedimentary successions of the deposited material show upward fining, which is in agreement with observations of chute cutoffs in rivers

  1. 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...

  2. 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...

  3. Démonstration expérimentale d'une distribution quantique de clé par codage temporel

    NASA Astrophysics Data System (ADS)

    Boucher, W.; Debuisschert, T.

    2006-10-01

    Nous avons démontré expérimentalement la transmission quantique de clé par codage temporel. Alice envoie des impulsions cohérentes atténuées. La clé est codée dans l'instant de détection des photons chez Bob. Une mesure de la durée de cohérence par moyen interférométrique permet d'assurer un fonctionnement en régime quantique. Nous avons mesuré un taux d'erreur quantique de 3.3% et une chute relative de contraste de l'interféromètre de 8.4%. Ces valeurs permettent d'évaluer un avantage d'information de 0.49 bit/impulsion pour Alice et Bob par rapport à un espion éventuel.

  4. Relationships of a novel objective chute score and exit velocity with growth performance of receiving cattle.

    PubMed

    Bruno, K A; Vanzant, E S; Vanzant, K A; McLeod, K R

    2016-11-01

    Animals with excitable temperaments often have decreased gains that have been associated with decreased intake and efficiency. Different temperament measures probably measure different specific underlying traits. Commonly used temperament measures include both objective and subjective measures. Subjective measures present potential difficulties for making across-study comparisons and thus for generalizing quantitative relationships. One objective of this experiment was to evaluate 2 related, but different, measures associated with temperament, where 1 measure is a new, objective measurement based on the common subjective chute score measures. Also, there is reason to believe that RDP requirements of animals may vary with temperament. To examine the relationships between temperament measures and nutrient use, 192 crossbred steers were used in a 58-d randomized complete block design experiment. Temperament treatments (assigned prior to d 1) were chute exit velocity (EV; slow vs. fast) and objective chute score (WSD; low vs. high), a novel temperament measure that was the SD of weights collected at 5 Hz for 10 s while an animal was restrained in a chute with its head caught. Both were measured on d -8, 1, 2, 16, 30, 56, and 58, where d 1 was the day that animals were allotted to treatment groups and began receiving experimental diets. Steers were fed a diet with 1 of 3 RDP levels (75%, 105%, and 120% of RDP requirements). There were no main effects or interactions with RDP ( ≥ 0.12); thus, it was removed from the statistical model for subsequent analyses. There were no interactions between EV and WSD ( ≥ 0.11). Slow EV animals had greater ADG ( = 0.02) and DMI ( ≤ 0.09) than fast EV animals, but there was no effect of EV on G:F ( > 0.14). For d 0 to 58, high WSD animals had greater DMI ( ≤ 0.09) than low WSD animals but no difference in ADG ( = 0.23), whereas low WSD animals tended to have increased G:F ( = 0.11). Results of this study give additional

  5. Safety assessment of discharge chute isolation barrier preparation and installation activities. Revision 3

    SciTech Connect

    Meichle, R.H.

    1994-11-08

    This revision adds a section addressing impacts of dropping surfacing tool and rack cutter on the basin floor, and corrects typographical errors. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparisons of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions was made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classifications.

  6. STS-65 Columbia, OV-102, with drag chute deployed lands at KSC SLF

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Space Shuttle Columbia, Orbiter Vehicle (OV) 102, its drag chute fully deployed, completes a record duration mission as it lands on Runway 33 at the Kennedy Space Center (KSC) Shuttle Landing Facility (SLF). A helicopter flying overhead observes as OV-102's nose landing gear (NLG) and main landing gear (MLG) roll along the runway. Landing occurred at 6:38 am (Eastern Daylight Time (EDT)). STS-65 mission duration was 14 days 17 hours and 56 minutes. Onboard were six NASA astronauts and a Japanese payload specialist who conducted experiments in support of the International Microgravity Laboratory 2 (IML-2) during the mission.

  7. Safety assessment of discharge chute isolation barrier preparation and installation. Revision 1

    SciTech Connect

    Meichle, R.H.

    1994-10-10

    This revision responds to RL comments and increases the discussion of the ``effective hazard categorization`` and the readiness review basis. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparison of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions were made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classification.

  8. Location of equipment in the 105K East discharge chute for installation of isolation barriers (ref USQ 94-0041): Revision 1

    SciTech Connect

    Hull, T.R.

    1994-11-04

    The scope of this report is to document the final location for equipment currently located in the 105 K-East discharge chute before beginning installation of the isolation barriers and equipment that will/may be left after completion of installation. The isolation barriers are to be installed at each basin in the openings between the discharge chute and the main basin. Once installed, the isolation barriers will remain in place, permanently isolating the discharge chute from direct communication with the main basin. After the isolation barriers are installed, the equipment left in the discharge chute will not be able to be moved out of the chute without being totally removed from the water. The equipment that will be addressed by this Supporting Document includes: Crusher, Dump Table, Packager, Seal Conveyor, Old Cofferdam Doors, Joint Cover and Location Bars, Canister Basket, Air Operated Sludge Pump and Discharge Hose, Fuel Segregation Canister Table, Seal Preparation Tool, and Miscellaneous tools and equipment.

  9. Experimental study on improvement effect of guide wall to water flow in bend of spillway chute.

    PubMed

    Zhang, Qinghua; Diao, Yanfang; Zhai, Xingtao; Li, Shuning

    2016-01-01

    In order to improve water flow in a bend of a spillway chute using a guide wall, modeling experiments with or without a guide wall under conditions of three different bend axial radii, three chute bottom slopes and three flow rates were carried out in this study. Two indexes were calculated, which are the improved water surface uniformity and the reduced rate of water surface difference in concave and convex banks of the cross-section. The results show that: (1) setting a guide wall in a bend can improve water flow in the bend because it increased the water surface uniformity of the cross-section and reduced the water surface difference in the concave and convex banks; (2) the smaller the bend axial radius, the better the water surface improvement effect will be using a guide wall; (3) the steeper the bottom slope, the more cross-sections with less water surface difference; and (4) flow rates have a great influence on water surface improvement in the bend, and the guide wall can improve water flow obviously when the water depth in the starting section of the bend is lower than the height of the guide wall. This study has important implications in engineering design of guide walls.

  10. Experiments using non-intrusive particle tracing techniques for granular chute flows. Final report

    SciTech Connect

    Rosato, A.D.; Dave, R.N.; Fischer, I.S.

    1998-12-31

    The objective of this contract was to develop a system capable of non-intrusively tracking the motion of an individual particle for the study of granular flows down inclined chutes. The result of the project is a system capable of following the three-dimensional translational and rotational motion of an individual particle embedded with a flowing granular material. The basic system consists of a sphere embedded with three orthogonal transmitters emitting at different frequencies which induce voltages in an antenna array surrounding the flow regime. Analysis of the induced voltage signals within the framework of a derived model yields both the position and orientation of the sphere. Tests were performed in a small scale model chute as well as in a cylindrical vibrated granular bed, which clearly demonstrates the capability of the system. As a result of discussions at meetings held semi-annually for the Granular Flow Advanced Research Objectives (GFARO) contractors, it was deemed necessary to pursue an additional experimental program as part of this contract related to the measurement of sphere collision properties. The outcome of the work (reported in Appendix C) is the determination of certain properties which are needed for use in computer simulations and theory.

  11. Snow avalanche speed determination using wireless accelerometers at the Weissfluhjoch Snow Chute

    NASA Astrophysics Data System (ADS)

    Vilajosana, I.; Schaefer, M.; Llosa, J.; Suriñach, E.; Marquès, J. M.; Kern, M. A.; Khazaradze, G.

    2009-04-01

    Experiments using a network of wireless accelerometers were carried out at the snow chute operated by the SLF at Weissfluhjoch (Switzerland) with an attempt to study internal dynamics of flowing snow. Several 2D and 3D wireless accelerometers placed in the starting zone prior to the experiments travelled within the flow when the avalanche was released. The characteristics of the sensors (size and density) allow the units to evolve like active particle tracers. Acceleration readings obtained at 85 Hz in 3 different experiments were analysed. The analysis methods used include Empirical Mode Decomposition and Kalman Filtering techniques to obtain reliable speed and position measurements from the single 2D and 3D acceleration measurements. The results are in agreement with those obtained from independent speed measurements from optical sensors and Video Images. The results although preliminary are promising. The information extracted could provide valuable information related to the internal dynamics of the avalanche. Small scale chutes are the ideal scenario for this type of experiment and new experiments using improved sensors are envisaged. Moreover, the potential of wireless technologies and wireless sensors to study natural phenomena such snow avalanches has been demonstrated. JAVA SUN Spot Project and The Spanish Ministerio de Educación y Ciencia Projects: CGL2006-06596/BTE and HU-2007-11 supported this research.

  12. Particulate Matter (PM) Pollution

    MedlinePlus

    ... Environmental Protection Agency Search Search Particulate Matter (PM) Pollution Contact Us Share Most PM particles form in ... and cause serious health effects. Particulate Matter (PM) Pollution PM Basics What is PM, and how does ...

  13. 78 FR 57876 - DeSoto and Boyer Chute National Wildlife Refuges; Washington County, Nebraska, and Harrison and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service DeSoto and Boyer Chute National Wildlife Refuges; Washington County, Nebraska, and Harrison and Pottawattamie Counties, Iowa; Draft Environmental Assessment and Comprehensive...

  14. 75 FR 7289 - Boyer Chute National Wildlife Refuge, NE; Hamden Slough National Wildlife Refuge, MN; and Iowa...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ... Refuge, MN; and Iowa Wetland Management District, IA AGENCY: Fish and Wildlife Service, Interior... documents for the Boyer Chute and Hamden Slough National Wildlife Refuges (NWRs) and the Iowa Wetland... Wildlife Refuge, 26624 N. Tower Road, Detroit Lakes, MN 56501; 3. Attention: Refuge Manager, Iowa...

  15. Studies of granular flow down an inclined chute. Quarterly technical progress report, March 13, 1992--June 12, 1992

    SciTech Connect

    Hanes, D.M.

    1992-09-01

    A preliminary series of experiments were run in order to examine the effects sidewalls have on the steady-state mass flow rate of granular material in a rectangular, inclined chute. These experiments also serve to assess the problems associated with the initial operation of the granular flow apparatus. Presumably, the friction between the sidewalls and the flowing material will slow the flow rate of that material. The relative effect of the sidewalls should decrease with increasing width for a given flow entrance condition. For instance, when the width of the chute is at a minimum (one grain diameter), the sidewalls will have a maximum frictional effect. And as the width approaches infinity, the sidewalls will have a minimum frictional effect. It is desired to know at what chute widths the sidewall effects will reasonably approach this minimum, if this condition can even be approached with the existing apparatus. The relationship between chute width and flow rate will be important to know during more involved experiments which will follow this initial investigation. These experiments will include the measurement of localized grain density, local velocity and individual grain dynamics (rotation and translation) and collisions. The secondary objective, to observe and correct problems with the system, is a more general and qualitative goal.

  16. Studies of granular flow down an inclined chute. Quarterly technical progress report, 13 June 1992--12 September 1992

    SciTech Connect

    Hanes, D.M.

    1992-12-01

    The driving force for the granular flow in the experimental region is gravity. The vehicle which re-circulates this flow is an 46 cm Corra-Trough belt conveyor manufactured by Buck-El, Inc. A drawing of this conveyor is shown in Figure 3. Entrance and exit chambers were designed to route the flow between the chute and the conveyor. Both devices had to be flexible because the position of the chute relative to the conveyor changes each time the angle of the chute is changed. Finally, to control the entering flow more accurately, an adjustable gate apparatus was constructed. The first step in setting up the chute is angle adjustment. The granular material used in the experiments described in this report are technical quality glass spheres, three millimeters in diameter. These beads are produced by Cataphote, Inc. Cataphote lists the tolerances for the 3mm spheres at {plus_minus}0.2 mm. The average mass of a single bead was measured to be 0.034 g which gives an average measured specific gravity of the glass at 2.42 g/cm{sup 3}.

  17. LDSD Chute

    NASA Image and Video Library

    2014-08-08

    Tears are visible in the parachute from NASA Supersonic Disk Sail Parachute, which did not deploy as expected. The photo was obtained by Navy divers during recovery of the LDSD test vehicle and parachute.

  18. Short communication: scoring of digital dermatitis during milking as an alternative to scoring in a hoof trimming chute.

    PubMed

    Thomsen, P T; Klaas, I C; Bach, K

    2008-12-01

    Digital dermatitis is a serious problem in dairy production in many countries. In many settings, it is important to evaluate the digital dermatitis status of individual cows or an entire dairy herd. Such an evaluation has traditionally been done in a hoof trimming chute. An evaluation in the milking parlor can take place without disturbing the cows to a large extent, it can be done using less labor compared with an evaluation in a hoof trimming chute, and is cheaper than using a chute. The objective was to evaluate the sensitivity and specificity of a rapid screening method for digital dermatitis in the milking parlor, without using any specialized tools and taking approximately 15 s/cow. All lactating cows in 3 commercial Danish dairy herds were included. Cows were first scored for the presence of digital dermatitis during milking and the next day all cows were scored during hoof trimming. A 6-point nominal scoring system based on a visual inspection of the digital dermatitis lesions was used. For the analysis, the scores were dichotomized (digital dermatitis positive or digital dermatitis negative). Additionally, lesions were classified as small (diameter 2 cm). Sensitivity and specificity were calculated using observations from the hoof trimming chute as the "gold standard" and observations during milking as the diagnostic test. Relatively large variation was found between herds with an overall sensitivity of 0.65 (95% confidence interval: 0.59 to 0.72) and a specificity of 0.84 (0.81 to 0.87). The sensitivity increased to 0.69 (0.62 to 0.76), when only large lesions were assessed. The method has several advantages compared with evaluation in a chute and may be a useful tool in the daily hoof health management in dairy herds.

  19. THE MEASURES PAR PROJECT

    NASA Astrophysics Data System (ADS)

    Frouin, R. J.; Franz, B.

    2009-12-01

    The solar energy available for photosynthesis, known as PAR, controls the growth of phytoplankton and, therefore, regulates the composition and evolution of marine ecosystems. Knowing the spatial and temporal distribution of PAR over the oceans is critical to understanding biogeochemical cycles of carbon, nutrients, and oxygen, and to address important climate and global change issues such as the fate of anthropogenic atmospheric carbon dioxide. In view of this, a 12-year time series of PAR at the ocean surface, starting in September 1997, is being produced by the NASA Ocean Biology Processing Group from SeaWiFS, MODIS-Terra, and MODIS-Aqua data. The product covers the global oceans, with a spatial resolution of about 9.3x9.3 km (equal area grid) and a temporal resolution of one day. PAR is computed as the difference between the 400-700 nm solar flux incident on the top of the atmosphere (known) and reflected back to space by the atmosphere and surface (derived from satellite radiance), taking into account atmospheric absorption (modeled). Knowledge of pixel composition is not required, eliminating the need for cloud screening and arbitrary assumptions about sub-pixel cloudiness. Combining data from satellite sensors with different equatorial crossing times accounts for the diurnal variability of clouds and, therefore, increases accuracy on a daily time scale. The processing system, including routine check of accuracy and control of quality, is designed to operate during the entire lifetime of SeaWiFS and MODIS, and to accommodate future sensors with ocean-color capabilities. Maps of daily, weekly, and monthly PAR obtained from individual sensors are presented, as well as merged products. Accuracy is quantified in comparisons with other satellite estimates, the National Centers for Environmental Prediction reanalysis product, and in-situ measurements from fixed buoys and platforms. The good statistical performance makes the satellite PAR product suitable for large

  20. Endeavour's drag chute opens as it lands at KSC on first attempt

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Endeavour's drag chute is deployed to slow its speed for landing on Runway 15 at the Shuttle Landing Facility at 6:03 p.m. EST. At the controls is Commander Brent Jett, completing the successful 10-day, 19-hour and 58-minute-long STS-97 mission. Other crew members on board are Pilot Michael Bloomfield and Mission Specialists Joseph Tanner, Carlos Noriega and Marc Garneau, with the Canadian Space Agency. On the 4.4-million-mile mission, Endeavour carried the P6 Integrated Truss Structure with solar arrays to power the International Space Station. The arrays and other equipment were installed during three EVAs that totaled 19 hours, 20 minutes. Endeavour was docked with the Space Station for 6 days, 23 hours, 13 minutes. This is the 16th nighttime landing for a Space Shuttle and the 53rd at Kennedy Space Center.

  1. How large grains increase bulk friction in bi-disperse granular chute flows

    NASA Astrophysics Data System (ADS)

    Staron, Lydie; Phillips, Jeremy C.

    2016-07-01

    In this contribution, we apply contact dynamics discrete simulations to explore how the mechanical properties of simple bi-dimensional granular chute flows are affected by the existence of two grain sizes. Computing partial stress tensors for the phases of small and large grains, we show that the phase of large grain exhibits a much larger shear strength than the phase of small grains. This difference translates in terms of the flow internal friction: adopting the μ (I) dependence to describe the flow frictional properties, we establish that the flow mean friction coefficient increases with the volume fraction of large grains. Hence, while the presence of large grains may induce lubrication in 3D unconfined flows due to the self-channelisation and levées formation, the effect of large grains on the bulk properties is to decrease the flow mobility.

  2. Accuracy of micro powder dosing via a vibratory sieve-chute system.

    PubMed

    Besenhard, M O; Faulhammer, E; Fathollahi, S; Reif, G; Calzolari, V; Biserni, S; Ferrari, A; Lawrence, S M; Llusa, M; Khinast, J G

    2015-08-01

    This paper describes a powder dosing system with a vibratory sieve mounted on a chute that doses particles into a capsule. Vertical vibration occurred with a broad range of frequencies and amplitudes. During dosing events, the fill weight was accurately recorded via a capacitance sensor, covering the capsules and making it possible to analyze filling characteristics, that is, the fill rates and their robustness. The range of frequencies and amplitudes was screened for settings that facilitated reasonable (no blocking, no spilling) fill rates for three lactose powders. The filling characteristics were studied within this operating space. The results reveal similar operating spaces for all investigated powders. The fill rate robustness varied distinctly in the operating space, which is of prime importance for selecting the settings for continuous feeding applications. In addition, we present accurate dosing studies utilizing the knowledge about the filling characteristics of each powder.

  3. Chutes and Ladders in Hepatitis C Nucleoside Drug Development§

    PubMed Central

    Coats, Steven J.; Garnier-Amblard, Ethel C.; Amblard, Franck; Ehteshami, Maryam; Amiralaei, Sheida; Zhang, Hongwang; Zhou, Longhu; Boucle, Sebastien R. L.; Lu, Xiao; Bondada, Lavanya; Shelton, Jadd R.; Li, Hao; Liu, Peng; Li, Chengwei; Cho, Jong Hyun; Chavre, Satish N.; Zhou, Shaoman; Mathew, Judy; Schinazi, Raymond F.

    2014-01-01

    Chutes and Ladders is an exciting up-and-down-again game in which players race to be the first to the top of the board. Along the way, they will find ladders to help them advance, and chutes that will cause them to move backwards. The development of nucleoside analogs for clinical treatment of hepatitis C presents a similar scenario in which taking shortcuts may help quickly advance a program, but there is always a tremendous risk of being sent backwards as one competes for the finish line. In recent years the treatment options for chronic hepatitis C virus (HCV) infection have expand due to the development of a replicon based in vitro evaluation system, allowing for the identification of multiple drugable viral targets along with a concerted and substantial drug discovery effort. Three major drug targets have reached clinical study for chronic HCV infection: the NS3/4A serine protease, the large phosphoprotein NS5A, and the NS5B RNA-dependent RNA polymerase. Recently, two oral HCV protease inhibitors were approved by the FDA and were the first direct acting anti-HCV agents to result from the substantial research in this area. There are currently many new chemical entities from several different target classes that are being evaluated worldwide in clinical trials for their effectiveness at achieving a sustained virologic response (SVR) (Pham et al., 2004; Radkowski et al., 2005). Clearly the goal is to develop therapies leading to a cure that are safe, widely accessible and available, and effective against all HCV genotypes (GT), and all stages of the disease. Nucleoside analogs that target the HCV NS5B polymerase that have reached human clinical trials is the focus of this review as they have demonstrated significant advantages in the clinic with broader activity against the various HCV GT and a higher barrier to the development of resistant viruses when compared to all other classes of HCV inhibitors. PMID:24275341

  4. Diesel particulate control

    SciTech Connect

    Bertelsen, F.I. )

    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.

  5. La pelade par plaques

    PubMed Central

    Spano, Frank; Donovan, Jeff C.

    2015-01-01

    Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre l’épidémiologie, la pathogenèse, l’histologie et l’approche clinique au diagnostic de la pelade par plaques. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant la pathogenèse, le diagnostic et le pronostic de la pelade par plaques. Message principal La pelade par plaques est une forme de perte pileuse auto-immune dont la prévalence durant une vie est d’environ 2 %. Des antécédents personnels ou familiaux de troubles auto-immuns concomitants, comme le vitiligo ou une maladie de la thyroïde, peuvent être observés dans un petit sous-groupe de patients. Le diagnostic peut souvent être posé de manière clinique en se fondant sur la perte de cheveux non cicatricielle et circulaire caractéristique, accompagnée de cheveux en « point d’exclamation » en périphérie chez ceux dont le problème en est aux premiers stades. Le diagnostic des cas plus complexes ou des présentations inhabituelles peut être facilité par une biopsie et un examen histologique. Le pronostic varie largement et de mauvais résultats sont associés à une apparition à un âge précoce, une perte importante, la variante ophiasis, des changements aux ongles, des antécédents familiaux ou des troubles auto-immuns concomitants. Conclusion La pelade par plaques est une forme auto-immune de perte de cheveux périodiquement observée en soins primaires. Les médecins de famille sont bien placés pour identifier la pelade par plaques, déterminer la gravité de la maladie et poser le diagnostic différentiel approprié. De plus, ils sont en mesure de renseigner leurs patients à propos de l’évolution clinique de la maladie ainsi que du pronostic général selon le sous-type de patients.

  6. 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)

  7. Pitch based foam with particulate

    SciTech Connect

    Klett, James W.

    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.

  8. 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)

  9. Airborne particulate discriminator

    DOEpatents

    Creek, Kathryn Louise; Castro, Alonso; Gray, Perry Clayton

    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.

  10. Particulate matter fugitive dusts

    SciTech Connect

    Not Available

    1988-01-01

    Topics covered in this conference include: Review of EPA's cost/benefit analysis for additional regulation of surface coal mines; Particulate monitoring on the Kilauea East Rift, Hawaii, and The MEDUSA sampling system: case histories in the measurement of particulate matter with wide spectrum analysis.

  11. Particulate fracture during deformation

    NASA Astrophysics Data System (ADS)

    Llorca, J.; Martin, A.; Ruiz, J.; Elices, M.

    1993-07-01

    The mechanisms of deformation and failure in a 2618 Al alloy reinforced with 15 vol pct SiC particilates were studied and compared with those of the unreinforced alloy, processed by spray forming as well. Tensile and fracture toughness tests were carried out on naturally aged and peak-aged specimens. The broken specimens were sliced through the middle, and the geometric features of fractured and intact particulates were measured. The experimental observations led to the conclusion that failure took place by the progressive fracture of the particulates until a critical volume fraction was reached. An influence of the particulate size and aspect ratio on the probability of fracture was found, the large and elongated particulates being more prone to fail, and the fracture stress in the particulates seemed to obey the Weibull statistics. The dif- ferences in ductility found between the naturally aged and peak-aged composites were explained in terms of the number of broken particulates as a function of the applied strain. Numerical simulations of the deformation process indicated that the stresses acting on the particulates are higher in the peak-aged material, precipitating the specimen failure. Moreover, the compressive residual stresses induced on the SiC during water quenching delayed the onset of particulate breakage in the naturally aged material.

  12. Fluidizing device for solid particulates

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    A flexible whip suspended in a hopper is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  13. LABORATORY AND FIELD EVALUATION OF INSTRUMENTATION FOR THE SEMI-CONTINUOUS DETERMINATION OF PARTICULATE NITRATE (AND OTHER WATER-SOLUBLE PARTICULATE COMPOUNDS)

    EPA Science Inventory

    Studies conducted at the EPA facility in Research Triangle Park, NC and at a field study in Southern California have demonstrated the capability for the semi-continuous determination of particulate nitrate (and other water soluble ionic species). Two instruments, a R&P 8400N par...

  14. LABORATORY AND FIELD EVALUATION OF INSTRUMENTATION FOR THE SEMI-CONTINUOUS DETERMINATION OF PARTICULATE NITRATE (AND OTHER WATER-SOLUBLE PARTICULATE COMPOUNDS)

    EPA Science Inventory

    Studies conducted at the EPA facility in Research Triangle Park, NC and at a field study in Southern California have demonstrated the capability for the semi-continuous determination of particulate nitrate (and other water soluble ionic species). Two instruments, a R&P 8400N par...

  15. Brulures par Diluant

    PubMed Central

    Benbrahim, A.; Jerrah, H.; Diouri, M.; Bahechar, N.; Boukind, E.H.

    2009-01-01

    Summary La flamme de diluant est une cause non rare de brûlure dans le contexte marocain. Nous avons jugé intéressant de faire une étude épidémiologique sur la brûlure par flamme de diluant (BFD) au centre national des brûlés (CNB) du CHU Ibn-Rochd de Casablanca. Ce travail a été réalisé sur une période de 10 mois (septembre 2007/juin 2008). Le but du travail est de montrer les caractéristiques de ce type de brûlures pour les prévenir et ce par l'information sur le diluant, produit causant ces brûlures, et ses différents dangers, la brûlure notamment. Durant cette période, nous avons colligé 17 cas de BFD sur un total de 356 patients admis au CNB pour brûlures aiguës toute étiologie confondue. La moyenne d'age des patients concernés est de 32 ans. Ils sont presque tous de sexe masculin (16 hommes/1 femme) et ont des antécédents de toxicomanie et/ou de délinquance. Tous nos patients sont de bas niveau socio-économique et habitent dans des bidonvilles pour la plupart. La brûlure est souvent secondaire à une agression dans la rue (92% des cas). Concernant les caractéristiques de la brûlure, la surface cutanée brûlée moyenne est de 23%; elle est souvent profonde et siège surtout au niveau des membres supérieurs et du tronc. PMID:21991179

  16. Mobilization of Floodplain Sediments by Chute Cutoffs on a Large River: Lower Wabash River, Illinois-Indiana

    NASA Astrophysics Data System (ADS)

    Zinger, J. A.; Rhoads, B. L.; Best, J.; Engel, F.; Konsoer, K. M.

    2010-12-01

    Bend cutoffs are a common mechanism of morphologic change in all scales of meandering rivers worldwide. Cutoffs can develop either by progressive migration of an elongated bend onto itself, forming a neck cutoff, or by erosion of a new channel across the neck of a bend, producing a chute cutoff. In contrast to the slow processes of “shaving” of the floodplain by outer bank erosion or formation of neck cutoffs by lateral channel migration, the sudden development of a chute cutoff channel can rapidly introduce a large volume of floodplain sediment into the downstream river channel. Formation of a chute cutoff channel also occurs on much shorter timescales than infilling of the subsequent oxbow lake. The asynchronous nature of such floodplain sediment release and storage resulting from cutoffs has important implications for longer-term floodplain sediment balance and the accurate modeling of floodplain evolution and architecture. In this study, using aerial photography and ground survey, we quantified the quantity of floodplain sediment mobilized by two chute cutoff events on Mackey Bend, a large, elongated meander of the lower Wabash River, IL-IN, located just upstream of the Ohio River confluence. A chute cutoff channel on this bend developed during flooding in June 2008 and was followed by formation of a second cutoff channel in July 2009. Here, we compare the volume of sediment released by these cutoff events to the background flux of sediment generated by lateral migration of the bend in the previous 78 years. Our study also explores the influence of these cutoff events on the morphology of the Wabash-Ohio confluence immediately downstream of the evolving chute cutoff channels. We found that, in just over two years, these cutoffs released c. 3. 6 million cubic meters of floodplain sediment, which is comparable to 4.6% of the annual sediment load of the Mississippi River. According to our calculations, it would take over 60 years of lateral migration of Mackey

  17. Into the deep: A coarse-grained carbonate turbidite thalweg generated by gigantic submarine chutes

    NASA Astrophysics Data System (ADS)

    Mulder, Thierry; Gillet, Hervé; Reijmer, John; Droxler, André; cavailhes, Thibault; Hanquiez, Vincent; Fauquembergue, Kelly; Bujan, Stéphane; Blanck, David; bashah, Sara; Guiastrennec, Léa; Fabregas, Natacha; Recouvreur, Audrey; Seibert, Chloé

    2017-04-01

    New high-resolution multibeam mapping, in the Southeastern Bahamas, images in exquisite details the southern part of Exuma Sound, and its unchartered transition area to the deep abyssal plain of the Western North Atlantic bounded by the Bahama Escarpment (BE) between San Salvador Island and Samana Cay, referred here to the San Salvador abyssal plain. The transition area is locally referred to as Crooked Island Passage, loosely delineated by Crooked, Long, and Conception Islands, Rum and Samana Cays. Surprisingly in such a pure carbonate landscape, the newly established map reveals the detailed and complex morphology of a giant valley formed by numerous gravity flows originated in Exuma Sound itself, in addition to many secondary slope gullies and smaller tributaries draining the surrounding upper slopes. The valley referred here as the Exuma canyon system starts with a perched valley with low sinuosity, characterized by several flow restrictions and knickpoints initiated by the presence of drowned isolated platforms and merging tributaries. The valley abruptly transforms itself into a deep incised canyon, rivaling the depth of the Colorado Grand Canyon, through two major knickpoints with outsized chutes exceeding several hundred of meters in height, a total of 1600-1800 m. The sudden transformation of the wide valley into a deep narrow canyon, occurring when the flows incised deep into an underlying lower Cretaceous drowned carbonate platform, generates a huge hydraulic jump and creates an enormous plunge pool and related deposits with mechanisms comparable to the ones operating along giant subaerial waterfalls. The high kinetic flow energy, constrained by this narrow and deeply incised canyon, formed, when it is released at its mouth in the abyssal plain, a wide deep-sea channel with well-developed levees and fan, made of coarse-grained carbonate defined layers separated by fine carbonate sediments mixed with fine siliciclastics transported along the BE by the

  18. Motion of a Granular Avalanche in an Exponentially Curved Chute: Experiments and Theoretical Predictions

    NASA Astrophysics Data System (ADS)

    Hutter, Kolumban; Koch, Thilo

    1991-01-01

    This paper describes a model to predict the flow of an initially stationary mass of cohesionless granular material down a rough curved bed, and checks it against laboratory experiments that were conducted with several cohesionless granular materials that are released from rest and travel in an exponentially curved chute. This work is of interest in connection with the motion of rock and ice avalanches and dense flow snow avalanches. We use the depth-averaged field equations of balance of mass and linear momentum as presented by Savage & Hutter (1990). These equations are evolution equations for the transversely averaged streamwise velocity and the distribution of avalanche depths and involve two phenomenological parameters, the internal angle of friction, φ , and a bed friction angle, δ , both as constitutive properties of Coulomb-type behaviour. We present the model but do not derive its equations, which are presented in two variants that incorporate weak and strong curvature effects. For granular avalanches which start as parabolic piles, the governing equations (incorporating weak curvature effects) permit similarity solutions. These solutions preserve the parabolic shape and have simple velocity distributions. We present the equations again without detailed explanations. Experiments were performed with seven different granular materials (two classes of glass beads, Vestolen plastic particles, two samples of quartz granules and two types of crunched marmor particles). Piles of finite masses of such granular materials with various initial geometries were released from rest in a 100 mm wide chute having an exponentially curved bed that was lined with Makrolon (a plexiglass), drawing-paper and sandpaper. The granular masses under motion were photographed and video filmed and thus the geometry of the avalanche was recorded as a function of position and time. With all materials and for all the bed linings, the angle of repose and the bed friction angle were

  19. X-29 Number Two in Flight Closeup of Spin Chute Mechanism

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Because the number two X-29 at NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center) flew at higher angles of attack than the number one aircraft, it required a spin chute system for safety. The system deployed a parachute for recovery of the aircraft if it inadvertently entered an uncontrolled spin. Most of the components of the spin chute system were located on a truss at the aft end of the aircraft. In addition, there were several cockpit modifications to facilitate use of the chute. The parachute was made of nylon and was of the conical ribbon type. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field

  20. Void/particulate detector

    DOEpatents

    Claytor, Thomas N.; Karplus, Henry B.

    1985-01-01

    Voids and particulates are detected in a flowing stream of fluid contained in a pipe by a detector which includes three transducers spaced about the pipe. A first transducer at a first location on the pipe transmits an ultrasonic signal into the stream. A second transducer detects the through-transmission of the signal at a second location and a third transducer at a third location upstream from the first location detects the back-scattering of the signal from any voids or particulates. To differentiate between voids and particulates a fourth transducer is positioned at a fourth location which is also upstream from the first location. The back-scattered signals are normalized with the through-transmission signal to minimize temperature fluctuations.

  1. 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.

  2. Microwave regenerated particulate trap

    SciTech Connect

    McDonald, A.C. Jr.; Yonushonis, T.M.; Haberkamp, W.C.; Mako, F.; Len, L.K,; Silberglitt, R.; Ahmed, I.

    1997-12-31

    It has been demonstrated that a fibrous particulate filter can extract particulate matter from the diesel exhaust. However, additional engineering efforts remains to achieve the design target of 90%. It has also be shown that with minor modifications magnetrons produced for home ovens can endure a simulated diesel operating environment. Much work remains to develop a robust product ready to complete extensive engine testing and evaluation. These efforts include: (1) additional environmental testing of magnetrons; (2) vibration testing of the filter in the housing; (3) evaluating alternative methods/designs to seal the center bore; and (4) determining the optimum coating thickness that provides sufficient structural integrity while maintaining rapid heating rates.

  3. Allongement compensatoire de quelques consonnes par suite de la chute du "e" caduc (Compensatory Lengthening of Certain Consonants As a Result of Dropping the Mute "e").

    ERIC Educational Resources Information Center

    Lebel, Jean-Guy

    1968-01-01

    The effect of a mute "e" on preceding consonant pairs was studied in the oscillographic tapings of the pronunciation of three well-educated Frenchmen. The 68 taped phrase pairs, showing the consonant in a primary and secondary (followed by mute "e") position, are listed. The differences betwee n the length of the first consonant, second consonant,…

  4. Flow structure and channel morphodynamics of meander bend chute cutoffs: A case study of the Wabash River, USA

    NASA Astrophysics Data System (ADS)

    Zinger, Jessica A.; Rhoads, Bruce L.; Best, James L.; Johnson, Kevin K.

    2013-12-01

    paper documents the three-dimensional structure of flow and bed morphology of two developing chute cutoffs on a single meander bend on the lower Wabash River, USA, and relates the flow structure to patterns of morphologic change in the evolving cutoff channels. The upstream end of the cutoff channels is characterized by: (1) a zone of flow velocity reduction/stagnation and bar development in the main channel across from the cutoff entrance, (2) flow separation and bar development along the inner (left) bank of the cutoff channel immediately downstream from the cutoff entrance, and (3) helical motion and outward advection of flow momentum entering the cutoff channel, leading to erosion of the outer (right) bank of the cutoff channel. At the downstream end of the cutoff channels, the major hydrodynamic and morphologic features are: (1) flow stagnation along the bank of the main channel immediately upstream of the cutoff channel mouth, (2) convergence of flows from the cutoff and main channels, (3) helical motion of flow from the cutoff, (4) a zone of reduced velocity along the bank of the main channel immediately downstream from the cutoff channel mouth, and (5) development of a prominent bar complex that penetrates into the main channel and extends from the stagnation zone upstream to downstream of the cutoff mouth. These results provide the basis for a conceptual model of chute-cutoff dynamics in which the upstream and downstream ends of a cutoff channel are treated as a bifurcation and confluence, respectively.

  5. Improving CO2 fixation with microalgae by bubble breakage in raceway ponds with up-down chute baffles.

    PubMed

    Cheng, Jun; Yang, Zongbo; Ye, Qing; Zhou, Junhu; Cen, Kefa

    2016-02-01

    The aeration gas was broken into smaller bubbles with enhanced local solution velocity to improve CO2 fixation with microalgae in raceway ponds with up-down chute baffles. A high-speed photography system and online precise pH probes were used to measure bubble generation and residence times, which were affected by paddlewheel speed, aerator orifice diameter, gas flow rate, and solution depth. Bubble generation time (from gas reaching aerator orifice surface to completely escaping from the aerator) decreased because of the enhanced local solution velocity, whereas bubble residence time increased because of the vortex flow field produced by up-down chute baffles. Bubble generation time decreased by 27% and bubble residence time increased by 27% when paddlewheel speed was 10r/min with an aeration gas rate of 0.03vvm. The decreased generation time and increased residence time of aeration bubbles promoted microalgae biomass yield by 29% in optimized flow fields in raceway ponds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Fluidizing device for solid particulates

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    1984-06-27

    A flexible whip or a system of whips with novel attachments is suspended in a hopper and is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  7. Fluidizing device for solid particulates

    DOEpatents

    Diebold, James P.; Scahill, John W.

    1986-01-01

    A flexible whip or a system of whips with novel attachments is suspended in a hopper and is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  8. An integrated management tool for rockfall evaluation along transportation corridors: the ParaChute research project

    NASA Astrophysics Data System (ADS)

    Cloutier, Catherine; Locat, Jacques; Mayers, Mélanie; Noël, François; Turmel, Dominique; Jacob, Chantal; Dorval, Pierre; Bossé, François; Gionet, Pierre; Jaboyedoff, Michel

    2016-04-01

    Rockfall is a significant hazard along linear infrastructures due to the presence of natural and man-made rock slopes. Knowing where the problematic rockfalls source areas are is of primary importance to properly manage and mitigate the risk associated to rockfall along linear infrastructures. The aim of the ParaChute research project is to integrate various technologies into a workflow for rockfall characterization for such infrastructures, using a 220 km-long railroad as the study site which is located on Québec's North Shore, Canada. The objectives of this 3-year project which started in 2014 are: (1) to optimize the use of terrestrial, mobile and airborne laser scanners data into terrain analysis, structural geology analysis and rockfall susceptibility rating, (2) to further develop the use of unmanned aerial vehicles (UAV) for photogrammetry applied to rock cliff characterization, and (3) to integrate rockfall simulation studies into a rock slope classification system similar to the Rockfall Hazard Rating System. Firstly, based on laser scanner data and aerial photographs, the morpho-structural features of the terrain (genetic material, landform, drainage, etc.) are mapped. The result can be used to assess all types of mass movements. Secondly, to guide field work and decrease uncertainty of various parameters, systematic rockfall simulations and a first structural analysis are made from point clouds acquired by mobile and airborne laser scanner. The simulation results are used to recognize the rock slopes that have potentially problematic rockfall paths, meaning they could reach the linear infrastructure. Other rock slopes are not included in the inventory. Field work is carried out to validate and complete the rock slopes characterization previously made from remote sensing technique. Because some or parts of cliffs are not visible or accessible from the railroad, we are currently developing the use of photogrammetry by UAV in order to complete the

  9. Signal processing and statistical descriptive reanalysis of steady state chute-flow experiments

    NASA Astrophysics Data System (ADS)

    truong, hoan; eckert, nicolas; keylock, chris; naaim, mohamed; bellot, hervé

    2014-05-01

    An accurate knowledge of snow rheology is needed for the mitigation against avalanche hazard. Indeed snow avalanches have a significant impact on the livelihoods and economies of alpine communities. To do so, 60 small-scale in-situ flow experiments were performed with various slopes, temperatures and flow depths. The investigation of these data previously seemed to show the dense flow of dry snow may be composed of two layers; a sheared basal layer made of single snow grains and a less sheared upper layer made of large aggregates. These outcomes were mainly based on the mean velocity profile of the flow and on interpretation in terms of rheological behavior of granular materials and snow microstructure [Pierre G. Rognon et al., 2007]. Here, the main objective remains the same, but the rheological and physical viewpoints are put aside to extract as much information contained in the data as possible various using signal processing methods and descriptive statistics methods as the maximum overlap discrete wavelet transform (MODWT), transfer entropy (TE) and maximum cross-correlation (MCC). Specifically, we aim at the improving the velocity estimations as function of the depth particularly the velocity fluctuations around the mean profile to better document the behavior of dense dry snow flows during a steady and uniform chute regime. The data are composed of pairs of voltage signals (right and left), which makes that the velocity is known indirectly only. The MCC method is classically used to determine the time lag between both signals. Previously, the MCC method that showed the mean velocity profile may be fitted by a simple bilinear function [Pierre G. Rognon et al., 2007], but no interesting temporal dynamics could be highlighted. Hence, a new process method was developed to provide velocity series with much better temporal resolution. The process is mainly made of a MODWT-based denoising method and the choice of window size for correlation. The results prove to be

  10. Particulate and multiphase processes

    SciTech Connect

    Ariman, T.; Veziroglu, T.N.

    1987-01-01

    This three-volume set provides information in particulate and multiphase processes. Authorities investigate four key areas of current scientific and engineering interest: aerosol science and technology; contamination analysis and control; suspensions and slurry transport; and fine particle powder science and technology.

  11. Analysis of microsize particulates

    NASA Technical Reports Server (NTRS)

    Blanchard, M. B.; Farlow, N. H.; Ferry, G. V.

    1972-01-01

    Unique methods for analyzing individual particles ranging in size from 0.01 to 1000 micrometers have been developed for investigation of nature of cosmic dust. Methods are applicable to particulate aerosols and contaminants characteristically encountered in studies of air pollution and in experiments designed to abate pollution.

  12. Instructions for Sampling Particulates.

    ERIC Educational Resources Information Center

    Ekman, Frank

    This technical report presents detailed instructions for sampling particulates. The table of contents includes sections on Introduction, Volume Determinations, Apparatus - Assembly and Operation, Sampling Techniques, and Acknowledgment. Six charts, 24 graphs, and one diagram are appended to facilitate sampling, as well as sections on Isokinetic…

  13. Par Pond vegetation status 1996

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-12-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned.

  14. Improved Satellite-based Photosysnthetically Active Radiation (PAR) for Air Quality Studies

    NASA Astrophysics Data System (ADS)

    Pour Biazar, A.; McNider, R. T.; Cohan, D. S.; White, A.; Zhang, R.; Dornblaser, B.; Doty, K.; Wu, Y.; Estes, M. J.

    2015-12-01

    One of the challenges in understanding the air quality over forested regions has been the uncertainties in estimating the biogenic hydrocarbon emissions. Biogenic volatile organic compounds, BVOCs, play a critical role in atmospheric chemistry, particularly in ozone and particulate matter (PM) formation. In southeastern United States, BVOCs (mostly as isoprene) are the dominant summertime source of reactive hydrocarbon. Despite significant efforts in improving BVOC estimates, the errors in emission inventories remain a concern. Since BVOC emissions are particularly sensitive to the available photosynthetically active radiation (PAR), model errors in PAR result in large errors in emission estimates. Thus, utilization of satellite observations to estimate PAR can help in reducing emission uncertainties. Satellite-based PAR estimates rely on the technique used to derive insolation from satellite visible brightness measurements. In this study we evaluate several insolation products against surface pyranometer observations and offer a bias correction to generate a more accurate PAR product. The improved PAR product is then used in biogenic emission estimates. The improved biogenic emission estimates are compared to the emission inventories over Texas and used in air quality simulation over the period of August-September 2013 (NASA's Discover-AQ field campaign). A series of sensitivity simulations will be performed and evaluated against Discover-AQ observations to test the impact of satellite-derived PAR on air quality simulations.

  15. Modelisation des emissions de particules microniques et nanometriques en usinage

    NASA Astrophysics Data System (ADS)

    Khettabi, Riad

    La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

  16. 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.

  17. Rigid particulate matter sensor

    SciTech Connect

    Hall, Matthew

    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.

  18. Regenerable particulate filter

    DOEpatents

    Stuecker, John N.; Cesarano, III, Joseph; Miller, James E.

    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.

  19. Modeling of Particulate Emissions

    DTIC Science & Technology

    2011-12-01

    vaporization CxHy H H2 C2H2 Alkylated- aromatics naphthenes Gas-phase kinetics PAH C2H2 . .... CO inception Surface growth & coalescence ageing...coagulation oxidation.... carbonization 14 Modeling Particulate Emissions Soot Formation Kinetics 2 1016 1 ]HC[kdt dS = Inception: Dimerization of...pyrene (and other 202 amu species), after Appel, et al, 2000. (Full detailed kinetics required!) Surface Growth: Mass growth (via acetylene addition

  20. 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.

  1. Russian Tu-144LL SST Flying Laboratory Landing with Drag Chutes at Zhukovsky Air Development Center

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The modified Tupolev Tu-144 supersonic flying laboratory touches down and deploys a trio of drag chutes following a test flight at the Zhukovsky Air Development Center near Moscow, Russia, in July 1997. NASA teamed with American and Russian aerospace industries for an extended period in a joint international research program featuring the Russian-built Tu-144LL supersonic aircraft. The object of the program was to develop technologies for a proposed future second-generation supersonic airliner to be developed in the 21st Century. The aircraft's initial flight phase began in June 1996 and concluded in February 1998 after 19 research flights. A shorter follow-on program involving seven flights began in September 1998 and concluded in April 1999. All flights were conducted in Russia from Tupolev's facility at the Zhukovsky Air Development Center near Moscow. The centerpiece of the research program was the Tu 144LL, a first-generation Russian supersonic jetliner that was modified by its developer/builder, Tupolev ANTK (aviatsionnyy nauchno-tekhnicheskiy kompleks-roughly, aviation technical complex), into a flying laboratory for supersonic research. Using the Tu-144LL to conduct flight research experiments, researchers compared full-scale supersonic aircraft flight data with results from models in wind tunnels, computer-aided techniques, and other flight tests. The experiments provided unique aerodynamic, structures, acoustics, and operating environment data on supersonic passenger aircraft. Data collected from the research program was being used to develop the technology base for a proposed future American-built supersonic jetliner. Although actual development of such an advanced supersonic transport (SST) is currently on hold, commercial aviation experts estimate that a market for up to 500 such aircraft could develop by the third decade of the 21st Century. The Tu-144LL used in the NASA-sponsored research program was a 'D' model with different engines than were used

  2. Sediment characteristics of the Yellowstone River in the vicinity of a proposed bypass chute near Glendive, Montana, 2011

    USGS Publications Warehouse

    Hanson, Brent R.

    2012-01-01

    In 2011, sediment data were collected by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers on the Yellowstone River at the location of a proposed bypass chute. The sediment data were collected to provide an understanding of the sediment dynamics of the given reach of the Yellowstone River. Suspended-sediment concentrations collected at the three sites generally decreased with decreasing streamflow. In general, the highest suspendedsediment concentrations were found near the channel bed and towards the center of the channel with lower suspendedsediment concentrations near the channel banks and water surface. Suspended sediment was the primary component of the total sediment load for all three sampling locations on the Yellowstone River and contributed at least 98 percent of the total sediment load at each of the three sites. The amount of bedload measured at the three sites was a smaller load in comparison with the suspended-sediment load.

  3. Optimizing gas transfer to improve growth rate of Haematococcus pluvialis in a raceway pond with chute and oscillating baffles.

    PubMed

    Yang, Zongbo; Cheng, Jun; Li, Ke; Zhou, Junhu; Cen, Kefa

    2016-08-01

    Up-down chute and oscillating (UCO) baffles were used to generate vortex and oscillating flow field to improve growth rate of Haematococcus pluvialis in a raceway pond. Effects of gas flow rate, solution velocity, and solution depth on solution mass transfer coefficient and mixing time were evaluated using online pH and dissolved oxygen probes. Mass transfer coefficient increased by 1.3 times and mixing time decreased by 33% when UCO baffles were used in the H. pluvialis solution, resulting in an 18% increase in biomass yield with 2% CO2. The H. pluvialis biomass yield further increased to 1.5g/L, and astaxanthin composition accumulated to 29.7mg/L under relatively higher light intensity and salinity.

  4. Exploration of locomotion in the ParA/ParB system

    NASA Astrophysics Data System (ADS)

    Jindal, Lavisha; Emberly, Eldon

    2015-03-01

    In many bacteria the ParA/ParB system is responsible for actively segregating DNA during replication. ParB precessively moves by hydrolyzing DNA bound ParA-ATP forming a depleted ParA region in its wake. Recent in-vitro experiments have shown that a ParB covered bead can traverse a ParA bound DNA substrate. It has been suggested that the formation of a gradient in ParA leads to diffusion-ratchet like motion of the ParB bead but its origin and potential consequences requires investigation. We have developed a deterministic model for the in-vitro ParA/ParB system and show that any amount of spatial noise in ParA can lead to the spontaneous formation of its gradient. The velocity of the bead is independent of this noise but depends on the scale over which ParA exerts a force on the bead and the scale over which ParB hydrolyzes ParA from the substrate. There is a particular ratio of these scales at which the velocity is a maximum. We also explore the effects of cooperative vs independent rebinding of ParA to the substrate. Our model shows how the driving force for ParB originates and highlights necessary conditions for directed motion in the in-vitro system that may provide insight into the in-vivo behaviour of the ParA/ParB system.

  5. Particulate emission reduction using additives

    SciTech Connect

    Rising, B.

    1998-07-01

    A particulate emission reduction study using a large industrial combustion turbine was undertaken. With heavy oil, both the mass particulate rate and smoke emissions exceeded original emission projections. Extensive particulate (gravimetric) emission tests were conducted to define the problem, and to assess specific corrective actions. Physical characterization of the particulate emissions revealed that the particulates from heavy oil were much larger than those found from lighter distillates. A review of the available literature on the subject was undertaken. Methods that were found to be effective at reducing smoke emissions were selected as a starting point. From this information, various techniques, including water injection, emulsification, and additive injection were evaluated to address both the visible smoke emissions and the particulate emission. Only the use of metal based fuel additives was found to be effective in reducing both visible smoke emissions and particulates. From vendor information, different additive time was selected for evaluation. Because of the complex chemistry of the fuel and additive mixtures, the vendor was required to optimize the additive carrier. Additives reduced particulates produced from the burning of heavy oil, but were found to be relatively ineffective with lighter distillate oils. Extensive chemical and physical characterization of the particulates were undertaken. From heavy oil, the particulates were found to be physically larger, greater than 5 microns. The additive was most effective on the heavy oils, but did not appear to alter the particulate size distribution. Additives did not appear to have any impact on the conversion of fuel bond sulfur into sulfuric acid mist. Additive dosage ratios were found which reduced the total particulate emission signature to meet current environmental requirements, while also nearly eliminating the plume visibility issues.

  6. 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.

  7. The Space Shuttle Endeavour's drag chute deploys to slow the orbiter as it rolls out on Runway 22 at Edwards Air Force Base at the conclusion of its 14-day STS-111 mission to the International Space Station

    NASA Image and Video Library

    2002-06-19

    The Space Shuttle Endeavour's drag chute deploys to slow the orbiter as it rolls out on Runway 22 at Edwards Air Force Base at the conclusion of its 14-day STS-111 mission to the International Space Station.

  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

  9. STS-76 Landing - Space Shuttle Atlantis Lands at Edwards Air Force Base, Drag Chute Deploy

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The space shuttle Atlantis touches down on the runway at Edwards, California, at approximately 5:29 a.m. Pacific Standard Time after completing the highly successful STS-76 mission to deliver Astronaut Shannon Lucid to the Russian Space Station Mir. She was the first American woman to serve as a Mir station researcher. Atlantis was originally scheduled to land at Kennedy Space Center, Florida, but bad weather there both 30 and 31 March necessitated a landing at the backup site at Edwards. This photo shows the drag chute deployed to help the shuttle roll to a stop. Mission commander for STS-76 was Kevin P. Chilton, and Richard A. Searfoss was the pilot. Ronald M. Sega was payload commander and mission specialist-1. Mission specialists were Richard Clifford, Linda Godwin and Shannon Lucid. The mission also featured a spacewalk while Atlantis was docked to Mir and experiments aboard the SPACEHAB module. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be

  10. STS-76 Landing - Space Shuttle Atlantis Lands at Edwards Air Force Base, Drag Chute Deploy

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The space shuttle Atlantis touches down on the runway at Edwards, California, at approximately 5:29 a.m. Pacific Standard Time after completing the highly successful STS-76 mission to deliver Astronaut Shannon Lucid to the Russian Space Station Mir. She was the first American woman to serve as a Mir station researcher. Atlantis was originally scheduled to land at Kennedy Space Center, Florida, but bad weather there both 30 and 31 March necessitated a landing at the backup site at Edwards. This photo shows the drag chute deployed to help the shuttle roll to a stop. Mission commander for STS-76 was Kevin P. Chilton, and Richard A. Searfoss was the pilot. Ronald M. Sega was payload commander and mission specialist-1. Mission specialists were Richard Clifford, Linda Godwin and Shannon Lucid. The mission also featured a spacewalk while Atlantis was docked to Mir and experiments aboard the SPACEHAB module. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be

  11. 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.

  12. 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.

  13. Assessing the representativeness of durability tests for wood pellets by DEM Simulation - Comparing conditions in a durability test with transfer chutes

    NASA Astrophysics Data System (ADS)

    Mahajan, Aditya; Dafnomilis, Ioannis; Hancock, Victoria; Lodewijks, Gabriel; Schott, Dingena

    2017-06-01

    Dust generation when handling wood pellets is related to the durability of the product, in other words the wear rate of particles subject to forces. During transport, storage and handling wood pellets undergo different forces when interacting with different pieces of equipment. This paper assesses the representativeness of the tumbling can test in relation to transfer chutes, by comparing forces acting on wood pellets in durability tests and in transfer chutes using DEM. The study also incorporates effects such as shape and size variations. The results showed that the tumbling can test underestimates compressive and tangential forces. Since the tested material is subject to milder conditions than in reality, it can be concluded that this test is not representative for the conditions in the supply chain of wood pellets.

  14. Evaluation of the in-flight noise signature of a 32-chute suppressor nozzle: Acoustic data report. [outdoor static and 40 x 80 ft. wind tunnel tests

    NASA Technical Reports Server (NTRS)

    Moore, M. T.; Doyle, V. L.

    1977-01-01

    Outdoor static and 40 x 80 FT wind tunnel tests of the J79-15 engine/nacelle system with the conic nozzle and 32-chute exhaust suppressor were conducted to acquire the data necessary to evaluate the simulated in-flight signature of an engine-size 32-chute exhaust nozzle suppressor using the 40 x 80 ft wind tunnel and to study possible engine core noise contamination of the jet signature. The tests are described and and a sampling of the data acquired is presented. Included are aero performance summaries, as-measured and composite 1/3 OBSPL spectra for the 70 ft sideline high and low mics from the outdoor static tests, sideline traverse spectra and internal noise measurements from both the outdoor static and the 40 x 80 ft wind tunnel tests.

  15. Par Pond Fish, Water, and Sediment Chemistry

    SciTech Connect

    Paller, M.H.; Wike, L.D.

    1996-06-01

    The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

  16. Directed and persistent movement arises from mechanochemistry of the ParA/ParB system

    NASA Astrophysics Data System (ADS)

    Hu, Longhua; Vecchiarelli, Anthony G.; Mizuuchi, Kiyoshi; Neuman, Keir C.; Liu, Jian

    The segregation of DNA prior to cell division is essential for faithful genetic inheritance. In many bacteria, segregation of the low-copy-number plasmids involves an active partition system composed of ParA ATPase and its stimulator protein ParB. Recent experiments suggest that ParA/ParB system motility is driven by a diffusion-ratchet mechanism in which ParB-coated plasmid both creates and follows a ParA gradient on the nucleoid surface. However, the detailed mechanism of ParA/ParB-mediated directed and persistent movement remains unknown. We develop a theoretical model describing ParA/ParB-mediated motility. We show that the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent cycling of ParA-nucleoid affinity to the motion of the ParB bound cargo. Paradoxically, the resulting processive motion relies on quenching diffusive plasmid motion through a large number of transient ParA/ParB-mediated tethers to the nucleoid surface. Our work sheds light on a new emergent phenomenon in which non-motor proteins work collectively via mechanochemical coupling to propel cargos -- an ingenious solution shaped by evolution to cope with the lack of processive motor proteins in bacteria.

  17. Hémangiome vertébrale géant révélé par un traumatisme lombaire: à propos d'un cas

    PubMed Central

    Mouhsine, Abdelilah; Essanhaji, Adil; Atmane, El Mehdi; Rokhssi, Radouane; Kadiri, B Ouchaib; Mahfoudi, Mbark; El Fikri, Abdelghani

    2014-01-01

    L'hémangiome vertebral est une tumeur bénigne fréquente, c'est une lésion bénigne habituellement asymptomatique. Les formes évolutives résponsables de compression médullaire sont beaucoup plus rares, une surveillance clinique et radiologique est conseillé. Nous mettons en exergue à travers ce cas revelé par des signes de compression médullaire suite à une chute, l'intérêt de l'imagerie en coupes dans le diagnostic positif; pour déceler les formes compliquées, et pour orienter l'attitude thérapeutique. Les formes neurologiques nécessitent une prise en charge neurochirurgicale. PMID:25574327

  18. Pressure driven particulate flows

    SciTech Connect

    Ingher, M.S.; Mondy, L.A.

    1996-03-01

    Numerical simulations of pressure-driven particulate Stokes flows are performed in cylindrical and rectangular conduits using a parallel boundary element code. Spherical particles are randomly placed in the conduits and a pressure drop between the ends of the conduits is imposed by the boundary conditions to induce a Poiseuille-like flow field. The instantaneous velocities of the particles are then calculated, as well as the additional pressure drop necessary to maintain a constant flow rate. Because the results depend on the spatial distribution of the particles, several random configurations of particles are examined for each case. Depending on two different interpretations of the numerical results, the solid phase can be represented as either leading or lagging the fluid phase. Both of the analyses and interpretations are presented.

  19. Particulate erosion mechanisms

    NASA Technical Reports Server (NTRS)

    Veerabhadrarao, P.; Buckley, D. H.

    1983-01-01

    Particulate damage and erosion of ductile metals are today plaguing design and field engineers in diverse fields of engineering and technology. It was found that too many models and theories were proposed leading to much speculation from debris analysis and failure mechanism postulations. Most theories of solid particle erosion are based on material removal models which do not fully represent the actual physical processes of material removal. The various mechanisms proposed thus far are: melting, low-cycle fatigue, extrusion, delamination, shear localization, adhesive material transfer, etc. The experimental data on different materials highlighting the observed failure modes of the deformation and cutting wear processes using optical and scanning electron microscopy are presented. The most important mechanisms proved from the experimental observations of the specimens exposed to both spherical and angular particles are addressed, and the validity of the earlier theories discussed. Both the initial stages of damage and advanced stages of erosion were studied to gain a fundamental understanding of the process.

  20. From meander bend to oxbow lake: flow, channel morphology and sedimentology of an evolving chute cutoff on the Wabash River, IL-IN

    NASA Astrophysics Data System (ADS)

    Zinger, J. A.; Rhoads, B. L.; Best, J. L.; Johnson, K.

    2012-12-01

    Chute channels develop on meandering rivers in a wide variety of environments, and in many cases result in bend cutoff and formation of an oxbow lake. During the transition from active meander bend to oxbow lake, the chute channel and original bend create a paired bifurcation-confluence unit. Here, we present field documentation of the evolving flow structure within a recent chute cutoff on the Wabash River, IL-IN, focusing on the bifurcation located on the upstream limb of the original bend. Previous studies indicate that this is the location of greatest sedimentation rates prior to complete plugging of the bend (e.g. Shields & Abt, 1989). We seek to isolate the fundamental processes causing rapid sedimentation in the upstream limb of the bend, using repeated hydroacoustic measurements of bed elevation and three-dimensional flow velocity at several key cross-sections. We also employ differential GPS surveys of channel banklines, analysis of aerial photographs and sampling of sediment on exposed bars at low flow, to aid interpretations of the cross-sectional data. This paper will detail the co-evolution of flow structure and channel morphology at this site and examine the coherent patterns of erosion and deposition responsible for oxbow lake formation. Reference: Shields, FD; Abt, SR (1989). Sediment deposition in cutoff meander bends and implications for effective management. Regulated Rivers: Research & Management 4, 381-396.

  1. Parallel Climate Analysis Toolkit (ParCAT)

    SciTech Connect

    Smith, Brian Edward

    2013-06-30

    The parallel analysis toolkit (ParCAT) provides parallel statistical processing of large climate model simulation datasets. ParCAT provides parallel point-wise average calculations, frequency distributions, sum/differences of two datasets, and difference-of-average and average-of-difference for two datasets for arbitrary subsets of simulation time. ParCAT is a command-line utility that can be easily integrated in scripts or embedded in other application. ParCAT supports CMIP5 post-processed datasets as well as non-CMIP5 post-processed datasets. ParCAT reads and writes standard netCDF files.

  2. Magnetic characterization of airborne particulates

    NASA Astrophysics Data System (ADS)

    Kim, W.; Doh, S.; Yu, Y.

    2010-12-01

    Burning fossil fuels from vehicles, domestics, industries and power plants in the large urban or industrial areas emit significant quantity of anthropogenic particulates which become a potential threat to human health. Here, we present temporal variability of particulate pollution associated with compositional differences, using magnetic measurements and electron microscopic observations. Six different grain-sizes of airborne particulates have been collected by filtering from 10 precipitation events in Seoul, Korea from February 2009 to June 2009. Magnetic concentration proxies show relatively better (R2 >0.6) and poorer correlations (R2 <0.3) with the masses of samples filtered by >0.45 μm and <0.45 μm sizes, respectively, suggesting the usefulness of magnetic characterization for the >0.45 μm particulates. Temporally, magnetic concentrations are higher in the cold season than the warm season. In particular, a significant increase of magnetic concentration is observed in 3 μm and 1 μm filters after the Chinese wind-blown dust events, indicating additional influx of fine-grained anthropogenic particulates into Seoul. Microscopic observations identify that increase of magnetic concentration is highly linked with the frequent occurrence of combustion derived particulates (i.e., carbon and/or sulfur mixed particles) than natural alumino-silicates. Overall, the present study demonstrates that magnetic measurements efficiently reflect the concentration of particulates produced from fossil-fuel combustion among the airborne particles from various sources.

  3. Overproduction and localization of Mycobacterium tuberculosis ParA and ParB proteins

    PubMed Central

    Maloney, Erin; Madiraju, Murty; Rajagopalan, Malini

    2011-01-01

    SUMMARY The ParA and ParB family proteins are required for accurate partitioning of replicated chromosomes. The Mycobacterium tuberculosis genome contains parB, parA and two parA homologs, Rv1708 and Rv3213c. It is unknown if parA and its homologs are functionally related. To understand the roles of ParA and ParB proteins in M. tuberculosis cell cycle, we have evaluated the consequences of their overproduction and visualized their localization patterns in M. smegmatis. We show that cells overproducing of ParA, Rv1708 and Rv3213c and ParB are filamentous and multinucleoidal indicating defects in cell cycle progression. Visualization of green-fluorescent protein fusions of ParA and its homologues showed similar localization patterns with foci at poles, quarter-cell, midcell positions and spiral-like structures indicating that they are functionally related. On the other hand, the ParBGFP fusion protein localized only to the cell poles. The cyan and yellow fluorescent fusion proteins of ParA and ParB, respectively, colocalized at the cell poles indicating that these proteins interact and possibly associate with the chromosomal origin of replication. Collectively our results suggest that the M. tuberculosis Par proteins play important roles in cell cycle progression. PMID:20006309

  4. suPAR: The Molecular Crystal Ball

    PubMed Central

    Thunø, Maria; Macho, Betina; Eugen-Olsen, Jesper

    2009-01-01

    soluble urokinase Plasminogen Activator Receptor (suPAR) levels reflect inflammation and elevated suPAR levels are found in several infectious diseases and cancer. suPAR exists in three forms; suPARI-III, suPARII-III and suPARI which show different properties due to structural differences. Studies suggest that full-length suPAR is a regulator of uPAR/uPA by acting as uPA-scavenger, whereas the cleaved suPARII-III act as a chemotactic agent promoting the immune response via the SRSRY sequence in the linker-region. This review focus on the various suPAR fragments and their involvement in inflammation and pathogenic processes. We focus on the molecular mechanisms of the suPAR fragments and the link to the inflammatory process, as this could lead to medical applications in infectious and pathological conditions. PMID:19893210

  5. 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.

  6. Directed and persistent movement arises from mechanochemistry of the ParA/ParB system

    PubMed Central

    Hu, Longhua; Vecchiarelli, Anthony G.; Mizuuchi, Kiyoshi; Neuman, Keir C.; Liu, Jian

    2015-01-01

    The segregation of DNA before cell division is essential for faithful genetic inheritance. In many bacteria, segregation of low-copy number plasmids involves an active partition system composed of a nonspecific DNA-binding ATPase, ParA, and its stimulator protein ParB. The ParA/ParB system drives directed and persistent movement of DNA cargo both in vivo and in vitro. Filament-based models akin to actin/microtubule-driven motility were proposed for plasmid segregation mediated by ParA. Recent experiments challenge this view and suggest that ParA/ParB system motility is driven by a diffusion ratchet mechanism in which ParB-coated plasmid both creates and follows a ParA gradient on the nucleoid surface. However, the detailed mechanism of ParA/ParB-mediated directed and persistent movement remains unknown. Here, we develop a theoretical model describing ParA/ParB-mediated motility. We show that the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent cycling of ParA–nucleoid affinity to the motion of the ParB-bound cargo. Paradoxically, this resulting processive motion relies on quenching diffusive plasmid motion through a large number of transient ParA/ParB-mediated tethers to the nucleoid surface. Our work thus sheds light on an emergent phenomenon in which nonmotor proteins work collectively via mechanochemical coupling to propel cargos—an ingenious solution shaped by evolution to cope with the lack of processive motor proteins in bacteria. PMID:26647183

  7. 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

  8. 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.

  9. Fishes of Missouri River, chute, and flood plain habitats: Chapter 4 in Initial biotic survey of Lisbon Bottom, Big Muddy National Fish and Wildlife Refuge

    USGS Publications Warehouse

    Grady, Joanne; Milligan, Jim; Chapman, Duane C.; Ehrhardt, Ellen A.; Dieterman, Douglas J.; Galat, David L.; Hooker, John; Kubisiak, John; DeLonay, Aaron; Little, Edward E.; Robinson, Jack; Tibbs, John

    1999-01-01

    The Lisbon Bottom Unit of the Big Muddy National Fish and Wildlife Refuge (Refuge) is approximately 2,200 acres and is the first complete unit of the Refuge. Primary objectives of the Refuge are to create and restore diverse riverine aquatic habitats and reconnect the Missouri River to its flood plain where feasible. Management seeks to accomplish these objectives by encouraging natural processes of erosion, deposition, and succession to the greatest extent possible.One of the most salient aquatic features of the Lisbon Bottom Unit is a newly created 2-mile-long free-flowing chute, or side channel (Fig. 1). This chute began forming as a levee breech scour hole during the Great Flood of 1993. The chute continued to develop during the 1995 flood and finally cut through to a flowing side channel during the 1996 flood. Extensive erosion and bank sluffing continued during 1997 due to sustained high flows that occurred throughout most of the year. The chute has progressively become wider and deeper with a developing meander pattern and channel bars have begun to form. Lisbon Bottom also contains several seasonal and permanent wetlands and is subject to periodic flooding at high Missouri River stages.Eight studies have been completed or are ongoing to evaluate Missouri River fishes associated with various habitat components of Lisbon Bottom and adjacent Missouri River reaches (Table 1). Several are part of much larger investigations to evaluate fish use of flood-created habitat features, basinwide fish assessment, and endangered or candidate species concerns.At the Lisbon Bottom Unit or in the Missouri River adjacent to the unit 54 fish species were collected (Table 2). Eight of these species have either a protected status under State or Federal laws or biologists consider them to potentially qualify for protected status. The status of the following fish is listed in Table 2: pallid sturgeon x shovelnose sturgeon hybrid, paddlefish, northern pike, sturgeon chub, sicklefin

  10. 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

  11. [Ambroise Paré, landlord].

    PubMed

    Pion-Graff, Joëlle; Bonnichon, Philippe

    2010-01-01

    Paré is well-known through many papers. His incomes allowed him to have a middle-class Parisian living. It is impossible to have an accurate knowledge of his fortune before his death but we have a good idea of his landed property. In fact as a Parishioner of Saint-Andre-des-Arts Church he probably was a landlord only in Paris and its vicinity with a building (rue de l'Hirondelle), two houses (rue Garancière), Meudon, Cormeille-en-Parisis and La-Ville-Du-Bois which the authors describe the present state of.

  12. 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.

  13. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition

    DOEpatents

    Gonze, Eugene V.; Brown, David B.

    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.

  14. PAR for the Course: A Congruent Pedagogical Approach for a PAR Methods Class

    ERIC Educational Resources Information Center

    Hammond, Joyce D.; Hicks, Maria; Kalman, Rowenn; Miller, Jason

    2005-01-01

    In the past two years, three graduate students and a senior faculty member have co-taught a participatory action research (PAR) course to undergraduate and graduate students. In this article the co-teachers advocate a set of pedagogical principles and practices in a PAR-oriented classroom that establishes congruency with community PAR projects in…

  15. Par Pond vegetation status Summer 1995 -- Summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-01-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

  16. Understanding particulate coating microstructure development

    NASA Astrophysics Data System (ADS)

    Roberts, Christine Cardinal

    How a dispersion of particulates suspended in a solvent dries into a solid coating often is more important to the final coating quality than even its composition. Essential properties like porosity, strength, gloss, particulate order, and concentration gradients are all determined by the way the particles come together as the coating dries. Cryogenic scanning electron microscopy (cryoSEM) is one of the most effective methods to directly visualize a drying coating during film formation. Using this method, the coating is frozen, arresting particulate motion and solidifying the sample so that it be imaged in an SEM. In this thesis, the microstructure development of particulate coatings was explored with several case studies. First, the effect of drying conditions was determined on the collapse of hollow latex particles, which are inexpensive whiteners for paint. Using cryoSEM, it was found that collapse occurs during the last stages of drying and is most likely to occur at high drying temperatures, humidity, and with low binder concentration. From these results, a theoretical model was proposed for the collapse of a hollow latex particle. CryoSEM was also used to verify a theoretical model for the particulate concentration gradients that may develop in a coating during drying for various evaporation, sedimentation and particulate diffusion rates. This work created a simple drying map that will allow others to predict the character of a drying coating based on easily calculable parameters. Finally, the effect of temperature on the coalescence and cracking of latex coatings was explored. A new drying regime for latex coatings was identified, where partial coalescence of particles does not prevent cracking. Silica was shown to be an environmentally friendly additive for preventing crack formation in this regime.

  17. 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...

  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. Process for particulate removal from coal liquids

    DOEpatents

    Rappe, Gerald C.

    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.

  20. 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)…

  1. Particulate matter and preterm birth

    EPA Science Inventory

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  2. Regional Background Fine Particulate Matter

    EPA Science Inventory

    A modeling system composed of the global model GEOS-Chem providing hourly lateral boundary conditions to the regional model CMAQ was used to calculate the policy relevant background level of fine particulate: matter. Simulations were performed for the full year of 2004 over the d...

  3. Particulate matter and preterm birth

    EPA Science Inventory

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  4. 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)…

  5. MODELING PARTICULATE CHARGING IN ESPS

    EPA Science Inventory

    In electrostatic precipitators there is a strong interaction between the particulate space charge and the operating voltage and current of an electrical section. Calculating either the space charge or the operating point when the other is fixed is not difficult, but calculating b...

  6. MODELING PARTICULATE CHARGING IN ESPS

    EPA Science Inventory

    In electrostatic precipitators there is a strong interaction between the particulate space charge and the operating voltage and current of an electrical section. Calculating either the space charge or the operating point when the other is fixed is not difficult, but calculating b...

  7. Particulate emissions from concentrated animal feeding operations

    USDA-ARS?s Scientific Manuscript database

    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. Comparative cactus architecture and par interception

    SciTech Connect

    Geller, G.N.; Nobel, P.S. )

    1987-07-01

    Because CO{sup 2} uptake by cacti can be limited by low levels of photosynthetically active radiation (PAR) and because plant form affects PAR interception, various cactus forms were studied using a computer model, field measurements, and laboratory phototropic studies. Model predictions indicated that CO{sub 2} uptake by individual stems at an equinox was greatest when the stem were vertical, but at the summer and the winter solstice CO{sub 2} uptake was greatest for stems titled 30{degree} away from the equator. Stem tilting depended on form and taxonomic group. Not only can the shape of cacti be affected by PAR, but also shape influences PAR interception and hence CO{sub 2} uptake.

  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

    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.

  11. Improved particulate-sampling filter

    NASA Technical Reports Server (NTRS)

    Hoffman, A. R.; Schneider, H. W.

    1980-01-01

    Small surface indentations entrain larger and more representative sampling than conventional petri-dish smeared with smooth layer adhesive. Filter is assembled from perforated disk and flat backing plate with sticky surface. Due to design-created currents, particulates come in contact with surface for longer time and have greater probability of being trapped. Filter is useful in air-quality monitoring at industrial sites, in mines, and in and around nuclear power plants.

  12. Material Instabilities in Particulate Systems

    NASA Technical Reports Server (NTRS)

    Goddard, J. D.

    1999-01-01

    Following is a brief summary of a theoretical investigation of material (or constitutive) instability associated with shear induced particle migration in dense particulate suspensions or granular media. It is shown that one can obtain a fairly general linear-stability analysis, including the effects of shear-induced anisotropy in the base flow as well as Reynolds dilatancy. A criterion is presented here for simple shearing instability in the absence of inertia and dilatancy.

  13. Ablation de ZnO par laser UV (193 nm) : nano-agrégats en phase gazeuse

    NASA Astrophysics Data System (ADS)

    Ozerov, I.; Bulgakov, A.; Nelson, D.; Castell, R.; Sentis, M.; Marine, W.

    2003-06-01

    La condensation de nano-agrégats d'oxyde de zinc en phase gazeuse est mise en évidence lors de l'ablation de ZnO massif par laser ArF pulsé. Nous comparons l'évolution spatio-temporelle de la forme du panache d'ablation (plume) de ZnO sous vide et sous atmosphère de gaz de couverture (oxygène et/ou hélium) à partir des images CCD et des résultats issus d'analyses spectroscopiques. L'expansion du plasma et la croissance des nano-clusters sont influencées par l'effet du confinement de la plume dû aux collisions entre les particules ablatées et les molécules de gaz ambiant ainsi que par les réactions chimiques dans le cas de l'oxygène. Le spectre de rayonnement du plasma est constitué principalement par l'émission d'atomes excités de Zn neutre. Nous avons observé la photoluminescence des nano-agrégats en suspension dans le gaz ainsi que leur décomposition par laser ArF.

  14. Techniques for measuring intercepted and absorbed PAR in corn canopies

    NASA Technical Reports Server (NTRS)

    Gallo, K. P.; Daughtry, C. S. T.

    1984-01-01

    The quantity of radiation potentially available for photosynthesis that is captured by the crop is best described as absorbed photosynthetically active radiation (PAR). Absorbed PAR (APAR) is the difference between descending and ascending fluxes. The four components of APAR were measured above and within two planting densities of corn (Zea mays L.) and several methods of measuring and estimating APAR were examined. A line quantum sensor that spatially averages the photosynthetic photon flux density provided a rapid and portable method of measuring APAR. PAR reflectance from the soil (Typic Argiaquoll) surface decreased from 10% to less than 1% of the incoming PAR as the canopy cover increased. PAR reflectance from the canopy decreased to less than 3% at maximum vegetative cover. Intercepted PAR (1 - transmitted PAR) generally overestimated absorbed PAR by less than 4% throughout most of the growing season. Thus intercepted PAR appears to be a reasonable estimate of absorbed PAR.

  15. Protease-activated receptor (PAR) 1 and PAR4 differentially regulate factor V expression from human platelets.

    PubMed

    Duvernay, Matthew; Young, Summer; Gailani, David; Schoenecker, Jonathan; Hamm, Heidi E; Hamm, Heidi

    2013-04-01

    With the recent interest of protease-activated receptors (PAR) 1 and PAR4 as possible targets for the treatment of thrombotic disorders, we compared the efficacy of protease-activated receptor (PAR)1 and PAR4 in the generation of procoagulant phenotypes on platelet membranes. PAR4-activating peptide (AP)-stimulated platelets promoted thrombin generation in plasma up to 5 minutes earlier than PAR1-AP-stimulated platelets. PAR4-AP-mediated factor V (FV) association with the platelet surface was 1.6-fold greater than for PAR1-AP. Moreover, PAR4 stimulation resulted in a 3-fold greater release of microparticles, compared with PAR1 stimulation. More robust FV secretion and microparticle generation with PAR4-AP was attributable to stronger and more sustained phosphorylation of myosin light chain at serine 19 and threonine 18. Inhibition of Rho-kinase reduced PAR4-AP-mediated FV secretion and microparticle generation to PAR1-AP-mediated levels. Thrombin generation assays measuring prothrombinase complex activity demonstrated 1.5-fold higher peak thrombin levels on PAR4-AP-stimulated platelets, compared with PAR1-AP-stimulated platelets. Rho-kinase inhibition reduced PAR4-AP-mediated peak thrombin generation by 25% but had no significant effect on PAR1-AP-mediated thrombin generation. In conclusion, stimulation of PAR4 on platelets leads to faster and more robust thrombin generation, compared with PAR1 stimulation. The greater procoagulant potential is related to more efficient FV release from intracellular stores and microparticle production driven by stronger and more sustained myosin light chain phosphorylation. These data have implications about the role of PAR4 during hemostasis and are clinically relevant in light of recent efforts to develop PAR antagonists to treat thrombotic disorders.

  16. ParCAT: Parallel Climate Analysis Toolkit

    SciTech Connect

    Smith, Brian E.; Steed, Chad A.; Shipman, Galen M.; Ricciuto, Daniel M.; Thornton, Peter E.; Wehner, Michael; Williams, Dean N.

    2013-01-01

    Climate science is employing increasingly complex models and simulations to analyze the past and predict the future of Earth s climate. This growth in complexity is creating a widening gap between the data being produced and the ability to analyze the datasets. Parallel computing tools are necessary to analyze, compare, and interpret the simulation data. The Parallel Climate Analysis Toolkit (ParCAT) provides basic tools to efficiently use parallel computing techniques to make analysis of these datasets manageable. The toolkit provides the ability to compute spatio-temporal means, differences between runs or differences between averages of runs, and histograms of the values in a data set. ParCAT is implemented as a command-line utility written in C. This allows for easy integration in other tools and allows for use in scripts. This also makes it possible to run ParCAT on many platforms from laptops to supercomputers. ParCAT outputs NetCDF files so it is compatible with existing utilities such as Panoply and UV-CDAT. This paper describes ParCAT and presents results from some example runs on the Titan system at ORNL.

  17. PAR2 regulates regeneration, transdifferentiation, and death

    PubMed Central

    Piran, Ron; Lee, Seung-Hee; Kuss, Pia; Hao, Ergeng; Newlin, Robbin; Millán, José Luis; Levine, Fred

    2016-01-01

    Understanding the mechanisms by which cells sense and respond to injury is central to developing therapies to enhance tissue regeneration. Previously, we showed that pancreatic injury consisting of acinar cell damage+β-cell ablation led to islet cell transdifferentiation. Here, we report that the molecular mechanism for this requires activating protease-activated receptor-2 (PAR2), a G-protein-coupled receptor. PAR2 modulation was sufficient to induce islet cell transdifferentiation in the absence of β-cells. Its expression was modulated in an islet cell type-specific manner in murine and human type 1 diabetes (T1D). In addition to transdifferentiation, PAR2 regulated β-cell apoptosis in pancreatitis. PAR2's role in regeneration is broad, as mice lacking PAR2 had marked phenotypes in response to injury in the liver and in digit regeneration following amputation. These studies provide a pharmacologically relevant target to induce tissue regeneration in a number of diseases, including T1D. PMID:27809303

  18. ATP-regulated interactions between P1 ParA, ParB and non-specific DNA that are stabilized by the plasmid partition site, parS

    PubMed Central

    Havey, James C.; Vecchiarelli, Anthony G.; Funnell, Barbara E.

    2012-01-01

    Localization of the P1 plasmid requires two proteins, ParA and ParB, which act on the plasmid partition site, parS. ParB is a site-specific DNA-binding protein and ParA is a Walker-type ATPase with non-specific DNA-binding activity. In vivo ParA binds the bacterial nucleoid and forms dynamic patterns that are governed by the ParB–parS partition complex on the plasmid. How these interactions drive plasmid movement and localization is not well understood. Here we have identified a large protein–DNA complex in vitro that requires ParA, ParB and ATP, and have characterized its assembly by sucrose gradient sedimentation and light scattering assays. ATP binding and hydrolysis mediated the assembly and disassembly of this complex, while ADP antagonized complex formation. The complex was not dependent on, but was stabilized by, parS. The properties indicate that ParA and ParB are binding and bridging multiple DNA molecules to create a large meshwork of protein–DNA molecules that involves both specific and non-specific DNA. We propose that this complex represents a dynamic adaptor complex between the plasmid and nucleoid, and further, that this interaction drives the redistribution of partition proteins and the plasmid over the nucleoid during partition. PMID:21965538

  19. Zone heated diesel particulate filter electrical connection

    DOEpatents

    Gonze, Eugene V.; Paratore, Jr., Michael J.

    2010-03-30

    An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

  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. Antithrombotic effects of PAR1 and PAR4 antagonists evaluated under flow and static conditions.

    PubMed

    Hosokawa, Kazuya; Ohnishi, Tomoko; Miura, Naoki; Sameshima, Hisayo; Koide, Takehiko; Tanaka, Kenichi A; Maruyama, Ikuro

    2014-01-01

    Thrombin-mediated activation of human platelets involves the G-protein-coupled protease-activated receptors PAR1 and PAR4. Inhibition of PAR1 and/or PAR4 is thought to modulate platelet activation and subsequent procoagulant reactions. However, the antithrombotic effects of PAR1 and PAR4 antagonism have not been fully elucidated, particularly under flow conditions. A microchip-based flow chamber system was used to evaluate the influence of SCH79797 (PAR1 antagonist) and YD-3 (PAR4 antagonist) on thrombus formation mediated by collagen and tissue thromboplastin at shear rates simulating those experienced in small- to medium-sized arteries (600s(-1)) and large arteries and small veins (240s(-1)). At a shear rate of 600s(-1), SCH79797 (10μM) efficiently reduced fibrin-rich platelet thrombi and significantly delayed occlusion of the flow chamber capillary (1.44 fold of control; P<0.001). The inhibitory activity of SCH79797 was diminished at 240s(-1). YD-3 (20μM) had no significant effect at either shear rate. The antithrombotic effects of SCH79797 were significantly augmented when combined with aspirin and AR-C66096 (P2Y12 antagonist), but not with YD-3. In contrast, no significant inhibition of tissue factor-induced clot formation under static conditions was observed in blood treated with SCH79797 and YD-3, although thrombin generation in platelet-rich plasma was weakly delayed by these antagonists. Our results suggest that the antithrombotic activities of PAR1 and/or PAR4 antagonism is influenced by shear conditions as well as by combined platelet inhibition with aspirin and a P2Y12-antagonist. © 2013.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Particulate Emissions from Gas Turbine Engines. Revision.

    DTIC Science & Technology

    1992-02-01

    with ferrocene additive) Particulate mass emissions from a J79-GE-IOB engine A-48 to A-64 Particulate mass emissions from a J52-P-6B engine A-65 to A...J79-CE-8D engine 4-9 1 with ferrocene additive (Summary of Files 34 through 45) 6 Particulate emissions from the ,J/7-G;E8f) engine 4 - 0l with... ferrocene additive (Summary of Files 46 and 47) 7 Particulate emissions from the J79-GE-8D engine 4-1i with ferrocene additive (Summary of Files 34 through

  8. 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.

  9. 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.

  10. Combustor for fine particulate coal

    DOEpatents

    Carlson, Larry W.

    1988-01-01

    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.

  11. 42 CFR 84.125 - Particulate tests; canisters containing particulate filters; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... filters; minimum requirements. 84.125 Section 84.125 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF... RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.125 Particulate tests; canisters containing particulate filters; minimum requirements. Gas mask canisters containing filters for protection against particulates (e.g...

  12. Humanizing the Protease-Activated Receptor (PAR) Expression Profile in Mouse Platelets by Knocking PAR1 into the Par3 Locus Reveals PAR1 Expression Is Not Tolerated in Mouse Platelets

    PubMed Central

    French, Shauna L.; Paramitha, Antonia C.; Moon, Mitchell J.; Dickins, Ross A.; Hamilton, Justin R.

    2016-01-01

    Anti-platelet drugs are the mainstay of pharmacotherapy for heart attack and stroke prevention, yet improvements are continually sought. Thrombin is the most potent activator of platelets and targeting platelet thrombin receptors (protease-activated receptors; PARs) is an emerging anti-thrombotic approach. Humans express two PARs on their platelets–PAR1 and PAR4. The first PAR1 antagonist was recently approved for clinical use and PAR4 antagonists are in early clinical development. However, pre-clinical studies examining platelet PAR function are challenging because the platelets of non-primates do not accurately reflect the PAR expression profile of human platelets. Mice, for example, express Par3 and Par4. To address this limitation, we aimed to develop a genetically modified mouse that would express the same repertoire of platelet PARs as humans. Here, human PAR1 preceded by a lox-stop-lox was knocked into the mouse Par3 locus, and then expressed in a platelet-specific manner (hPAR1-KI mice). Despite correct targeting and the predicted loss of Par3 expression and function in platelets from hPAR1-KI mice, no PAR1 expression or function was detected. Specifically, PAR1 was not detected on the platelet surface nor internally by flow cytometry nor in whole cell lysates by Western blot, while a PAR1-activating peptide failed to induce platelet activation assessed by either aggregation or surface P-selectin expression. Platelets from hPAR1-KI mice did display significantly diminished responsiveness to thrombin stimulation in both assays, consistent with a Par3-/- phenotype. In contrast to the observations in hPAR1-KI mouse platelets, the PAR1 construct used here was successfully expressed in HEK293T cells. Together, these data suggest ectopic PAR1 expression is not tolerated in mouse platelets and indicate a different approach is required to develop a small animal model for the purpose of any future preclinical testing of PAR antagonists as anti-platelet drugs. PMID

  13. Airborne particulate matter in spacecraft

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Acceptability limits and sampling and monitoring strategies for airborne particles in spacecraft were considered. Based on instances of eye and respiratory tract irritation reported by Shuttle flight crews, the following acceptability limits for airborne particles were recommended: for flights of 1 week or less duration (1 mg/cu m for particles less than 10 microns in aerodynamic diameter (AD) plus 1 mg/cu m for particles 10 to 100 microns in AD); and for flights greater than 1 week and up to 6 months in duration (0.2 mg/cu m for particles less than 10 microns in AD plus 0.2 mg/cu m for particles 10 to 100 microns in AD. These numerical limits were recommended to aid in spacecraft atmosphere design which should aim at particulate levels that are a low as reasonably achievable. Sampling of spacecraft atmospheres for particles should include size-fractionated samples of 0 to 10, 10 to 100, and greater than 100 micron particles for mass concentration measurement and elementary chemical analysis by nondestructive analysis techniques. Morphological and chemical analyses of single particles should also be made to aid in identifying airborne particulate sources. Air cleaning systems based on inertial collection principles and fine particle collection devices based on electrostatic precipitation and filtration should be considered for incorporation into spacecraft air circulation systems. It was also recommended that research be carried out in space in the areas of health effects and particle characterization.

  14. Southern Fine Particulate Monitoring Project

    SciTech Connect

    Ashley Williamson

    2003-05-31

    This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.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. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.

  15. PARTICULATE MATTER, OXIDATIVE STRESS AND ...

    EPA Pesticide Factsheets

    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary disorders. Clinical and experimental studies have historically focused on the cardiopulmonary effects of PM. However, since PM particles carry numerous biocontaminants that are capable of triggering free radical production and cytokine release, the possibility that PM may affect organs systems sensitive to oxidative stress must be considered. Four independent studies that summarize the neurochemical and neuropathological changes found in the brains of PM exposed animals are described here. These were recently presented at two 2007 symposia sponsored by the Society of Toxicology (Charlotte, NC) and the International Neurotoxicology Association (Monterey, CA). Particulates are covered with biocontaminants (e.g., endotoxins, mold, pollen) which convey free radical activity that can damage the lipids, nucleic acids, and proteins of target cells on contact and stimulate inflammatory cytokine release. Although, the historical focus of PM toxicity has been cardiopulmonary targets, it is now appreciated that inhaled nano-size (<100 nm) particles quickly exit the lungs and enter the circulation where they distribute to various organ systems (l.e., liver, kidneys, testes, lymph nodes) (Takenaka et aI

  16. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation.

    PubMed

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta; Jakimowicz, Dagmara

    2016-04-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins.

  17. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation

    PubMed Central

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta

    2016-01-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces. To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins. PMID:27248800

  18. 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.

  19. Testing Students' Use of the Particulate Theory

    ERIC Educational Resources Information Center

    Williamson, Vickie; Huffman, Jason; Peck, Larry

    2004-01-01

    High School students' understanding about the particulate theory of matter and their use of particulate terminology is investigated. The Physical Changes Concepts Test (PCCT) was administered in two forms, an applied version and a theoretical version, to determine whether students scientifically understood the concepts well enough to apply them to…

  20. Air Quality Criteria for Particulate Matter.

    ERIC Educational Resources Information Center

    National Air Pollution Control Administration (DHEW), Washington, DC.

    To assist states in developing air quality standards, this book offers a review of literature related to atmospheric particulates and the development of criteria for air quality. It not only summarizes the current scientific knowledge of particulate air pollution, but points up the major deficiencies in that knowledge and the need for further…

  1. suPAR and Team Nephrology

    PubMed Central

    2014-01-01

    Primary focal segmental glomerulosclerosis (FSGS) accounts for nearly 10 % of patients who require renal replacement therapy. Elevated circulating levels of soluble urokinase receptor (suPAR) have been identified as a biomarker to discriminate primary FSGS from other glomerulopathies. Subsequent reports have questioned the diagnostic utility of this test. In a study in BMC Medicine, Huang et al. demonstrate that urinary soluble urokinase receptor (suPAR) excretion assists in distinguishing primary FSGS from other glomerular diseases, and that high plasma suPAR concentrations are not directly linked to a decline in glomerular filtration rate (GFR). This observation suggests that further investigation of suPAR is warranted in patients with FSGS. It should be interpreted in light of a recent report that B7-1 is expressed in the podocytes of a subset of patients with FSGS, and that blocking this molecule may represent the first successful targeted intervention for this disease. These advances highlight the rapid pace of scientific progress in the field of nephrology. Nephrologists should work together, share resources, and expedite the design of protocols to evaluate these novel biomarkers in a comprehensive and scientifically valid manner. Please see related article http://www.biomedcentral.com/1741-7015/12/81. PMID:24885021

  2. Electrically heated particulate filter propagation support methods and systems

    DOEpatents

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

    2011-06-07

    A control system that controls regeneration of a particulate filter is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate combustion of particulate matter in the particulate filter. A propagation module estimates a propagation status of the combustion of the particulate matter based on a combustion temperature. A temperature adjustment module controls the combustion temperature by selectively increasing a temperature of exhaust that passes through the particulate filter.

  3. Advanced Fine Particulate Characterization Methods

    SciTech Connect

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  4. PAR Corneal Topography System (PAR CTS): the clinical application of close-range photogrammetry.

    PubMed

    Belin, M W; Cambier, J L; Nabors, J R; Ratliff, C D

    1995-11-01

    The PAR Corneal Topography System (CTS) is a computer-driven corneal imaging system which uses close-range photogrammetry (rasterphotogrammetry) to measure and produce a topographic map of the corneal surface. The PAR CTS makes direct point-by-point measurements of surface elevation using a stereo-triangulation technique. The CTS uses a grid pattern composed of horizontal and vertical lines spaced about 0.2 mm (200 microns) apart. Each grid intersection comprises a surface feature which can be located in multiple images and used to generate an (x,y,z) coordinate. Unlike placido disc-based videokeratoscopes, the PAR CTS requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. In addition to surface elevation, the PAR CTS computes axial and tangential curvatures and refractive power. Difference maps are available in all curvatures, refractive power, and in absolute elevation.

  5. Methods for Coating Particulate Material

    NASA Technical Reports Server (NTRS)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2013-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  6. 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.

  7. Ice particulates in the mesosphere

    NASA Technical Reports Server (NTRS)

    Chesworth, E. T.; Hale, L. C.

    1974-01-01

    The observations of noctilucent clouds, the measurements of hydrated and of large immobile ions, and the light-scattering layer detected by the OGO-6 satellite suggest the presence of particulates, probably ice, in the mesosphere. The correlation between temperature and positive ion conductivity where the vapor pressure over ice becomes greater than atmospheric pressure in the stratopause region indicates the presence of ice crystals throughout the mesosphere over a wide range of latitudes during all seasons. Between one and ten billion ice crystals per cubic meter of order 10 nanometers in diameter can dominate ionization loss processes in the mesosphere, and can explain a variety of experimental observations, including observed solar angle dependence and seasonal variability of electron density.

  8. View from west to east of PAR site resident engineer's ...

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

    View from west to east of PAR site resident engineer's office building (REOB) - Stanley R. Mickelsen Safeguard Complex, Resident Engineers Office Building, Southeast of intersection of PAR Access Road & Fourth Avenue, Nekoma, Cavalier County, ND

  9. Time Scales in Particulate Systems

    NASA Astrophysics Data System (ADS)

    Zhang, Duan

    2013-06-01

    While there are many interests of studying interactions of individual particles, macroscopic collective behavior of particles are our main interest in many practical applications. In this talk, I will give a brief overview of the multiscale methods connecting the physics at individual particles to macroscopic quantities and averaged equations. The emphasis will be on dense dissipative particulate systems, such as powders. Unlike conservative particle systems, such as molecular systems, in a dissipative particle system the concept of thermodynamic equilibrium is not very useful unless in very special cases, because the only true thermodynamically equilibrium state in these systems is the state in which nothing moves. Other than idealized simple systems, mesoscale structures are common and important in many practical systems, especially in dissipative systems. Spatial correlations of these mesoscale structures, such as force chains in dense granular system, particle clusters and streamers in fluidized beds have received some recent attentions, partly because they can be visualized. This talk will emphasize the effects of time correlations related to the mesoscale structures. To consider time correlations and history information of the system, I will introduce the mathematical foundation of the Liouville equation, its applicability and limitations. I will derive the generalized Liouville equations for particulate systems with and without interstitial fluids, and then use them to study averaged transport equations and related closures. Interactions among the time scale of particle interactions, the time scale of the mesocale structures, and the time scale of the physical problem as represented by strain rate will be discussed. The effect of these interactions on the closure relations will be illustrated. I will also discuss possible numerical methods of solving the averaged equations, and multiscale numerical algorithms bridging the particle level calculations to

  10. Élaboration de films de molécules organiques par ablation par laser UV

    NASA Astrophysics Data System (ADS)

    Hernandez-Perez, M. A.; Garapon, C.; Champeaux, C.; Coleman, A. W.

    2006-12-01

    Les potentialités des méthodes de dépôt par ablation laser (PLD) pour la préparation de films minces de matériaux organiques sont illustrées par un bref rappel bibliographique et par des résultats expérimentaux concernant des molécules d'intérêt biologique (acides aminés, calix-arènes, protéines). Les films sont préparés par PLD avec un laser KrF sans dégradation de la structure chimique des molécules dans une gamme de fluences de quelques dizaines à quelques centaines de mJ/cm2. Les propriétés structurales et optiques des films sont étudiées en fonction de la fluence du laser et mettent en évidence des arrangements moléculaires particuliers induits par cette méthode de dépôt. Le guidage optique a été obtenu pour des films de toutes ces molécules.

  11. A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition Assembly

    SciTech Connect

    B Chaudhuri; S Gupta; V Urban; M Chance; R DMello; L Smith; K Lyons; J Gee

    2011-12-31

    Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

  12. Kallikrein 6 Signals through PAR1 and PAR2 to Promote Neuron Injury and Exacerbate Glutamate Neurotoxicity

    PubMed Central

    Yoon, Hyesook; Radulovic, Maja; Wu, Jianmin; Blaber, Sachiko I.; Blaber, Michael; Fehlings, Michael G.; Scarisbrick, Isobel A.

    2014-01-01

    CNS trauma generates a proteolytic imbalance contributing to secondary injury, including axonopathy and neuron degeneration. Kallikrein 6 (Klk6) is a serine protease implicated in neurodegeneration and here we investigate the role of protease activated receptors 1 (PAR1) and PAR2 in mediating these effects. First we demonstrate Klk6 and the prototypical activator of PAR1, thrombin, as well as PAR1 and PAR2, are each elevated in murine experimental traumatic spinal cord injury (SCI) at acute or subacute time points. Recombinant Klk6 triggered ERK1/2 signaling in cerebellar granule neurons and in the NSC34 spinal cord motoneuron cell line, in a PI3K and MEK-dependent fashion. Importantly, lipopeptide inhibitors of PAR1 or PAR2, and PAR1 genetic deletion, each reduced Klk6-ERK1/2 activation. In addition, Klk6 and thrombin promoted degeneration of cerebellar neurons and exacerbated glutamate neurotoxicity. Moreover, genetic deletion of PAR1 blocked thrombin-mediated cerebellar neurotoxicity and reduced the neurotoxic effects of Klk6. Klk6 also increased glutamate-mediated Bim signaling, PARP cleavage and lactate dehydrogenase (LDH) release in NSC34 motoneurons and these effects were blocked by PAR1 and PAR2 lipopeptide inhibitors. Taken together these data point to a novel Klk6-signaling axis in CNS neurons that is mediated by PAR1 and PAR2 and is positioned to contribute to neurodegeneration. PMID:23647384

  13. A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition

    SciTech Connect

    Chaudhuri, Barnali; Gupta, Sayan; Urban, Volker S; Chance, Mark; D'Mello, Rhijuta; Smith, Lauren; Lyons, Kelly; Gee, Jessica

    2010-01-01

    Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

  14. Host response biomarker in sepsis: suPAR detection.

    PubMed

    Giamarellos-Bourboulis, Evangelos J; Georgitsi, Marianna

    2015-01-01

    Recent studies of our group have shown that suPAR may complement APACHE II score for risk assessment in sepsis. suPAR may be measured in serum of patients by an enzyme immunosorbent assay developed by Virogates (suPARnostic™). Production of suPAR from circulating neutrophils and monocytes may be assessed after isolation of neutrophils and monocytes and ex vivo culture. This is followed by measurement of suPAR in culture supernatants.

  15. Drosophila 14-3-3/PAR-5 is an essential mediator of PAR-1 function in axis formation.

    PubMed

    Benton, Richard; Palacios, Isabel M; St Johnston, Daniel

    2002-11-01

    PAR-1 kinases are required to determine the anterior-posterior (A-P) axis in C. elegans and Drosophila, but little is known about their molecular function. We identified 14-3-3 proteins as Drosophila PAR-1 interactors and show that PAR-1 binds a domain of 14-3-3 distinct from the phosphoserine binding pocket. PAR-1 kinases phosphorylate proteins to generate 14-3-3 binding sites and may therefore directly deliver 14-3-3 to these targets. 14-3-3 mutants display identical phenotypes to par-1 mutants in oocyte determination and the polarization of the A-P axis. Together, these results indicate that PAR-1's function is mediated by the binding of 14-3-3 to its substrates. The C. elegans 14-3-3 protein, PAR-5, is also required for A-P polarization, suggesting that this is a conserved mechanism by which PAR-1 establishes cellular asymmetries.

  16. Electrically heated particulate filter enhanced ignition strategy

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J

    2012-10-23

    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 applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.

  17. Diesel particulate emission control without engine modifications

    SciTech Connect

    Filowitz, M.S.; Vataru, M.

    1989-01-01

    This paper describes an ashless, fuel supplement which was found to typically reduce diesel particulate emissions by over 30% while significantly improving fuel economy and power output without any modifications to existing diesel engines or fuels. The treating cost is an order of magnitude less than the estimated cost of reducing aromatic content at the refinery to achieve particulate reductions. The particulate reduction is virtually all from the carbon (soot) fraction. The reduced soot formation translates into less abrasives and less soot-loading stress on the engine oil. Diesel tests conducted are also discussed.

  18. Particulate contamination spectrometer. Volume 1: Technical report

    NASA Technical Reports Server (NTRS)

    Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.

    1975-01-01

    A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate (dusts, aerosols, ice particles, etc.) contaminants. Detection of the particulates was achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meter/second. The LPS system was designed to operate in the high vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.

  19. [Ambroise Paré in French literature].

    PubMed

    Dumaitre, P

    1995-01-01

    The 16th century by its passionate side has been the favourite one of authors of historical novels in which among the heroes of "cloak and dagger stories" appears sometime Ambroise Paré. Alexandre Dumas (the father) has shown him at the court of Charles IX in La Reine Margot (1845) where he does not however play a great role. On the contrary, Balzac in Le Martyr calviniste (1842) has given him a capital part close to the dying François II, whom he intended to trepanize but had to give up this idea as a consequence of the opposition of the queen-mother Catherine de Médicis. In the present century, Robert Merle in Paris ma bonne ville (Fortune de France, 3, 1980) shows Paré at the time of the Saint Barthélemy.

  20. [Ambroise Paré and Latin].

    PubMed

    Drouin, Emmanuel

    2010-06-01

    We report a study of a medical book written by Antoine Mizaud (Memorabilium utilium, in ac iucundorum aphorismos Arcanorum omnis generis locupletes, perpulchre digestae), which was written in Latin, but has been extensively annotated in French.The book is from the personal collection of one of the physicians of Napoleon III. There is an oral tradition within his family that one of the works in the book had been annotated by Ambroise Paré. We know very little, apart from a few receipts and his signature, about the writing of the master of French surgery. Did he understand the language of Galen? There are many annotated passages in the works of Pare which are in the book. We examine whether these annotations were actually made by Ambroise Paré or whether they were done for him.

  1. Les Brulures Chimiques Par Le Laurier Rose

    PubMed Central

    Bakkali, H.; Ababou, M.; Nassim Sabah, T.; Moussaoui, A.; Ennouhi, A.; Fouadi, F.Z.; Siah, S.; Ihrai, H.

    2010-01-01

    Summary Le laurier rose ou Nerium oleander est un arbuste qui pousse naturellement dans les régions méditerranéennes. Au Maroc on le trouve dans les lieux humides. Il est réputé par ses risques de toxicité systémique en cas d'empoisonnement à cause de la présence de deux alcaloïdes, surtout l'oléandrine. La littérature illustre des cas d'utilisation locale des feuilles de cette plante contre la gale, les hémorroïdes et les furoncles. Nous rapportons deux cas de brûlures chimiques par le laurier rose de gravité différente. Cela doit aboutir à une information élargie de la population, ainsi qu'une réglementation stricte de sa commercialisation. PMID:21991211

  2. Combined DSEK and Transconjunctival Pars Plana Vitrectomy

    PubMed Central

    Sane, Mona; Shaikh, Naazli

    2016-01-01

    We report here three patients who underwent combined Descemet's stripping with endothelial keratoplasty and transconjunctival pars plana vitrectomy for bullous keratopathy and posterior segment pathology. A surgical technique and case histories are described. Anatomic and visual outcomes of combined Descemet's stripping with endothelial keratoplasty and vitrectomy were excellent. Our experience provides technical guidelines and limitations. The combined minimally invasive techniques allow for rapid anatomical recovery and return of function and visual acuity in a single sitting. PMID:27413563

  3. Par Pond refill water quality sampling

    SciTech Connect

    Koch, J.W. II; Martin, F.D.; Westbury, H.M.

    1996-08-01

    This study was designed to document anoxia and its cause in the event that the anoxia caused a fish kill. However, no fish kill was observed during this study, and dissolved oxygen and nutrient concentrations generally remained within the range expected for southeastern reservoirs. Par Pond water quality monitoring will continue during the second summer after refill as the aquatic macrophytes become reestablished and nutrients in the sediments are released to the water column.

  4. 40 CFR 60.422 - Standards for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for particulate matter. 60... Manufacture § 60.422 Standards for particulate matter. On or after the date on which the performance test... sulfate dryer, particulate matter at an emission rate exceeding 0.15 kilogram of particulate per...

  5. 40 CFR 60.422 - Standards for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for particulate matter. 60... Manufacture § 60.422 Standards for particulate matter. On or after the date on which the performance test... sulfate dryer, particulate matter at an emission rate exceeding 0.15 kilogram of particulate per...

  6. 40 CFR 60.422 - Standards for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for particulate matter. 60... Manufacture § 60.422 Standards for particulate matter. On or after the date on which the performance test... sulfate dryer, particulate matter at an emission rate exceeding 0.15 kilogram of particulate per...

  7. Particulate matter, oxidative stress and neurotoxicity.

    EPA Science Inventory

    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary dis...

  8. OPEN PATH OPTICAL SENSING OF PARTICULATE MATTER

    EPA Science Inventory

    The paper discusses the concepts behind recent developments in optical remote sensing (ORS) and the results from experiments. Airborne fugitive and fine particulate matter (PM) from various sources contribute to exceedances of state and federal PM and visibility standards. Recent...

  9. Particulate matter, oxidative stress and neurotoxicity.

    EPA Science Inventory

    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary dis...

  10. PARTICULATE MATTER, OXIDATIVE STRESS AND NEUROTOXICITY

    EPA Science Inventory

    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary dis...

  11. OPEN PATH OPTICAL SENSING OF PARTICULATE MATTER

    EPA Science Inventory

    The paper discusses the concepts behind recent developments in optical remote sensing (ORS) and the results from experiments. Airborne fugitive and fine particulate matter (PM) from various sources contribute to exceedances of state and federal PM and visibility standards. Recent...

  12. PARTICULATE MATTER, OXIDATIVE STRESS AND NEUROTOXICITY

    EPA Science Inventory

    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary dis...

  13. Contribution of wastewater discharges to ocean surface particulates

    SciTech Connect

    Bracewell, L.W.; Selleck, R.E.; Carter, R.

    1980-08-01

    The results of a survey in the Southern California Bight indicated that much of the floatable particulates in the vicinity of primary treatment outfalls originated in wastewater. Most of the particulates of this origin were composed of grease and wax. These particulates also contained appreciable concentrations of coliform bacteria. The particulates from primary effluents had large proportions of unsaturated 18-carbon fatty acids, whereas secondary effluent particulates resembled open-ocean particulates in proportions of fatty acids. Larger particulates were quickly dispersed. Surface concentrations of 3-mg hexane-extractable matter/m/sup 2/ or less probably are aesthetically acceptable.

  14. New ESP additive controls particulates

    SciTech Connect

    Durham, M.D.; Baldrey, K.E.; Bustard, C.J.; Martin, C.E.; Dharmarajan, N.N.

    1997-06-01

    This article reports that a conditioning agent enhanced precipitator performance after plant switched to low-sulfur coal. Firing low-sulfur coal at a power plant designed for medium- or high-sulfur coal will impact the downstream particulate control device. Since the performance of an electro-static precipitator (ESP) is a strong function of the sulfur content in the coal, switching to a low-sulfur coal will severely impact collection efficiency. Particle resistivity is the dominant parameter affecting the performance of an ESP. When the resistivity is too high, the ESP must be increased in size by a factor of two to three, resulting in proportionally increased capital and operating costs. Fly ash from low-sulfur coal is known to have a typical resistivity one or two orders of magnitude above that for ideal collection efficiency in a well-designed ESP. Therefore, when a utility burning a medium- or high-sulfur coal switches to a low-sulfur coal, the increase in particle resistivity resulting from the reduced SO{sub 3} concentration will lead to severe problems in the ESP. There have been many instances where utilities have switched from a high- to a low-sulfur coal, and the problems caused by the increased resistivity have had such a devastating effect on the performance of the ESP that emissions have increased by a factor of 10.

  15. The Particulate Air Pollution Controversy

    PubMed Central

    Phalen, Robert F.

    2004-01-01

    Scientists, regulators, legislators, and segments of industry and the lay public are attempting to understand and respond to epidemiology findings of associations between measures of modern particulate air pollutants (PM) and adverse health outcomes in urban dwellers. The associations have been interpreted to imply that tens of thousands of Americans are killed annually by small daily increments in PM. These epidemiology studies and their interpretations have been challenged, although it is accepted that high concentrations of air pollutants have claimed many lives in the past. Although reproducible and statistically significant, the relative risks associated with modern PM are very small and confounded by many factors. Neither toxicology studies nor human clinical investigations have identified the components and/or characteristics of PM that might be causing the health-effect associations. Currently, a massive worldwide research effort is under way in an attempt to identify whom might be harmed and by what substances and mechanisms. Finding the answers is important, because control measures have the potential not only to be costly but also to limit the availability of goods and services that are important to public health. PMID:19330148

  16. Shear Jamming in Particulate Media

    NASA Astrophysics Data System (ADS)

    Bertrand, Thibault; O'Hern, Corey S.; Shattuck, Mark D.

    2014-11-01

    More than two decades ago, Liu and Nagel introduced the concept of jamming and proposed a phase diagram for the jamming transition as a function of applied shear stress, density, and temperature. Since then, numerous computational as well as experimental studies have underscored the usefulness of this concept in systems ranging from colloidal glasses to packings of granular materials. Recently, Bi et al. presented experimental results that suggested that jamming via isotropic compression can lead to different packings than those generated via shear. To investigate fundamental aspects of shear-induced jamming, we performed numerical simulations and theoretical analyses of frictionless and frictional particulate media undergoing simple shear. We are able to predict the form of the boundaries in the shear-jamming phase diagram and determine how they change with system size. We also study the relationship between the shear-jamming phase diagram and the fluctuations in the stress versus strain for packings undergoing continuous shear in the context of geometrical families of packings.

  17. Hypocoordinated solids in particulate media.

    PubMed

    Bertrand, Thibault; Schreck, Carl F; O'Hern, Corey S; Shattuck, Mark D

    2014-06-01

    We propose a "phase diagram" for particulate systems with purely repulsive contact forces, such as granular media and colloids. We characterize two classes of behavior as a function of the input kinetic energy per degree of freedom T_{0} and packing fraction deviation from jamming onset Δϕ=ϕ-ϕ_{J} using simulations of frictionless disks. Isocoordinated solids (ICS) exist above jamming; they possess an average contact number equal to the isostatic value z_{iso}. ICS display "strict" harmonic response, where the density of vibrational modes from the Fourier transform of the velocity autocorrelation function is a set of sharp peaks at eigenfrequencies ω_{k}{d} of the dynamical matrix. In contrast, hypocoordinated solids (HCS) occur above and below jamming and possess fluctuating networks of interparticle contacts but do not undergo cage-breaking particle rearrangements. The density of vibrational frequencies for the HCS is not a collection of sharp peaks at ω_{k}{d}, but it does possess a common form over a range of Δϕ and T_{0}.

  18. Hypocoordinated solids in particulate media

    NASA Astrophysics Data System (ADS)

    Bertrand, Thibault; Schreck, Carl F.; O'Hern, Corey S.; Shattuck, Mark D.

    2014-06-01

    We propose a "phase diagram" for particulate systems with purely repulsive contact forces, such as granular media and colloids. We characterize two classes of behavior as a function of the input kinetic energy per degree of freedom T0 and packing fraction deviation from jamming onset Δϕ =ϕ-ϕJ using simulations of frictionless disks. Isocoordinated solids (ICS) exist above jamming; they possess an average contact number equal to the isostatic value ziso. ICS display "strict" harmonic response, where the density of vibrational modes from the Fourier transform of the velocity autocorrelation function is a set of sharp peaks at eigenfrequencies ωkd of the dynamical matrix. In contrast, hypocoordinated solids (HCS) occur above and below jamming and possess fluctuating networks of interparticle contacts but do not undergo cage-breaking particle rearrangements. The density of vibrational frequencies for the HCS is not a collection of sharp peaks at ωkd, but it does possess a common form over a range of Δϕ and T0.

  19. MTCI acoustic agglomeration particulate control

    SciTech Connect

    Chandran, R.R.; Mansour, M.N.; Scaroni, A.W.; Koopmann, G.H.; Loth, J.L.

    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.

  20. SOUTHERN FINE PARTICULATE MONITORING PROJECT

    SciTech Connect

    Unknown

    2002-04-01

    This quarterly report presents results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the January-March, 2002 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. Some instrumental issues were noted with the upgrade of the APS model 3320 are described in the report, as well as preliminary performance indications for the upgraded instrument. During the quarter preliminary data analysis and modeling studies were conducted to test the potential of the North Birmingham site data for source attribution analyses. Our initial assessment has continued to be optimistic in this regard due to the location of the site relative to several important classes of local and midrange emission sources. We anticipate that these analyses will provide good separations of the effects of major source classes and spatial source clusters, and will provide useful information relevant to PM{sub 2.5} implementation strategies.

  1. Sedimentary particulate iron: the missing micronutrients ?

    NASA Astrophysics Data System (ADS)

    Beghoura, Houda; Gorgues, Thomas; Aumont, Olivier; Planquette, Hélène

    2017-04-01

    Iron is known to regulate the marine primary production and to impact the structure of ecosystems. Indeed, iron is the limiting nutrient for the phytoplankton growth over about 30% of the global ocean. However, the nature of the external sources of iron to the ocean and their quantification remain uncertain. Among these external sources, the sediment sources have been recently shown to be underestimated. Besides, since the operationally defined dissolved iron (which is the sum of truly dissolved and colloidal iron) was traditionally assumed to be the only form available to phytoplankton and bacteria, most studies have focused on the supply of dissolved iron to the ocean, the role of the particulate fraction of iron being largely ignored. This traditional view has been recently challenged, noticeably, by observational evidences. Indeed, in situ observations have shown that large amounts of particulate iron are being resuspended from continental margins to the open ocean thanks to fine grained particles' transport over long distances. A fraction of this particulate iron may dissolve and thereby fuel the phytoplankton growth. The magnitude of the sedimentary sources of particulate iron and the releasing processes affecting this iron phase are not yet well constrained or quantified. As a consequence, the role of sedimentary particulate iron in the biogeochemical cycles is still unclear despite its potentially major widespread importance. Here, we propose a modeling exercise to assess the first order impacts of this newly considered particulate sedimentary iron on global ocean biogeochemistry. We designed global experiments with a coupled dynamical-biogeochemical model (NEMO-PISCES). First, a control simulation that includes only a sediment source of iron in the dissolved phase has been run. Then, this control simulation is being compared with simulations, in which we include a sediment source of iron in both phases (dissolved as well as particulate). Those latter

  2. New and Novel Technologies in Particulate Filtration

    DTIC Science & Technology

    2006-01-01

    be stacked up to provide more air as required. The HEPA filter media is a glass and polymer fiber blend, and is pleated to provide more filter ...filtration for Collective Protection Systems (CPS) uses high efficiency particulate air (HEPA) filters . These filters are excellent at removing an extremely...high percentage of biological and particulate material from the air, with relatively low pressure drop and energy consumption. These filters have

  3. Particulate matter in the Venus atmosphere

    NASA Technical Reports Server (NTRS)

    Ragent, B.; Esposito, L. W.; Tomasko, M. G.; Marov, M. IA.; Shari, V. P.

    1985-01-01

    The paper presents a summary of the data currently available (June 1984) describing the planet-enshrouding particulate matter in the Venus atmosphere. A description and discussion of the state of knowledge of the Venus clouds and hazes precedes the tables and plots. The tabular material includes a precis of upper haze and cloud-top properties, parameters for model-size distributions for particles and particulate layers, and columnar masses and mass loadings.

  4. Critical Role for PAR1 in Kallikrein 6-Mediated Oligodendrogliopathy

    PubMed Central

    Burda, Joshua E.; Radulovic, Maja; Yoon, Hyesook; Scarisbrick, Isobel A.

    2014-01-01

    Kallikrein 6 (Klk6) is a secreted serine protease preferentially expressed by oligodendroglia in CNS white matter. Elevated levels of Klk6 occur in actively demyelinating multiple sclerosis (MS) lesions and in cases of spinal cord injury (SCI), stroke and glioblastoma. Taken with recent evidence establishing Klk6 as a CNS-endogenous activator of protease-activated receptors (PARs), we hypothesized that Klk6 activates a subset of PARs to regulate oligodendrocyte physiology and potentially pathophysiology. Here, primary oligodendrocyte cultures derived from wild type or PAR1-deficient mice and the murine oligodendrocyte cell line, Oli-neu, were used to demonstrate that Klk6 mediates loss of oligodendrocyte processes and impedes morphological differentiation of oligodendrocyte progenitor cells (OPCs) in a PAR1-dependent fashion. Comparable gliopathy was also elicited by the canonical PAR1 agonist, thrombin, as well as PAR1-activating peptides (PAR1-APs). Klk6 also exacerbated ATP-mediated oligodendrogliopathy in vitro, pointing to a potential role in augmenting excitotoxicity. In addition, Klk6 suppressed the expression of proteolipid protein (PLP) RNA in cultured oligodendrocytes by a mechanism involving PAR1-mediated Erk1/2 signaling. Microinjection of PAR1 agonists, including Klk6 or PAR1-APs, into the dorsal column white matter of PAR+/+ but not PAR−/− mice promoted vacuolating myelopathy and a loss of immunoreactivity for myelin basic protein (MBP) and CC-1+ oligodendrocytes. These results demonstrate a functional role for Klk6-PAR1 signaling in oligodendroglial pathophysiology and suggest that PAR1 or PAR1-agonists may represent new targets to moderate demyelination and to promote myelin regeneration in cases of CNS white matter injury or disease. PMID:23832758

  5. Ablation d'un film d'or par laser à excimère

    NASA Astrophysics Data System (ADS)

    Sentis, M.; Hermann, J.; Pereira, A.; Delaporte, Ph.; Marine, W.; Perrière, J.; Bianchi, L.; Galli, R.

    2003-06-01

    Ces travaux de recherche ont été réalisés dans le cadre du projet de développement du Laser MégaJoule (LMJ). Parmi les expériences d'interaction laser - matière à très haut flux, certaines conduiront à un dépôt de particules d'or sur les éléments internes de la chambre d'interaction. Pour nettoyer ce dépôt de particules, la possibilité d'utiliser un procédé automatisé basé sur l'ablation laser a été étudiée. Un modèle numérique simplifié a été développé et une étude expérimentale réalisée sur des échantillons d'acier inoxydable ou de B4C recouverts d'un film d'or d'une épaisseur de ~20 nm déposés par PVD. Ces travaux montrent que plus de 95 % du film d'or peuvent être enlevés avec quelques tirs d'un laser XeCI dès que la densité d'énergie dépasse 3 J/cm^2.

  6. The novel PAR2 ligand C391 blocks multiple PAR2 signalling pathways in vitro and in vivo

    PubMed Central

    Boitano, Scott; Hoffman, Justin; Flynn, Andrea N; Asiedu, Marina N; Tillu, Dipti V; Zhang, Zhenyu; Sherwood, Cara L; Rivas, Candy M; DeFea, Kathryn A; Vagner, Josef; Price, Theodore J

    2015-01-01

    Background and Purpose Proteinase-activated receptor-2 (PAR2) is a GPCR linked to diverse pathologies, including acute and chronic pain. PAR2 is one of the four PARs that are activated by proteolytic cleavage of the extracellular amino terminus, resulting in an exposed, tethered peptide agonist. Several peptide and peptidomimetic agonists, with high potency and efficacy, have been developed to probe the functions of PAR2, in vitro and in vivo. However, few similarly potent and effective antagonists have been described. Experimental Approach We modified the peptidomimetic PAR2 agonist, 2-furoyl-LIGRLO-NH2, to create a novel PAR2 peptidomimetic ligand, C391. C391 was evaluated for PAR2 agonist/antagonist activity to PAR2 across Gq signalling pathways using the naturally expressing PAR2 cell line 16HBE14o-. For antagonist studies, a highly potent and specific peptidomimetic agonist (2-aminothiazo-4-yl-LIGRL-NH2) and proteinase agonist (trypsin) were used to activate PAR2. C391 was also evaluated in vivo for reduction of thermal hyperalgesia, mediated by mast cell degranulation, in mice. Key Results C391 is a potent and specific peptidomimetic antagonist, blocking multiple signalling pathways (Gq-dependent Ca2+, MAPK) induced following peptidomimetic or proteinase activation of human PAR2. In a PAR2-dependent behavioural assay in mice, C391 dose-dependently (75 μg maximum effect) blocked the thermal hyperalgesia, mediated by mast cell degranulation. Conclusions and Implications C391 is the first low MW antagonist to block both PAR2 Ca2+ and MAPK signalling pathways activated by peptidomimetics and/or proteinase activation. C391 represents a new molecular structure for PAR2 antagonism and can serve as a basis for further development for this important therapeutic target. PMID:26140338

  7. Ecological effects of particulate matter.

    PubMed

    Grantz, D A; Garner, J H B; Johnson, D W

    2003-06-01

    Atmospheric particulate matter (PM) is a heterogeneous material. Though regulated as un-speciated mass, it exerts most effects on vegetation and ecosystems by virtue of the mass loading of its chemical constituents. As this varies temporally and spatially, prediction of regional impacts remains difficult. Deposition of PM to vegetated surfaces depends on the size distribution of the particles and, to a lesser extent, on the chemistry. However, chemical loading of an ecosystem may be determined by the size distribution as different constituents dominate different size fractions. Coating with dust may cause abrasion and radiative heating, and may reduce the photosynthetically active photon flux reaching the photosynthetic tissues. Acidic and alkaline materials may cause leaf surface injury while other materials may be taken up across the cuticle. A more likely route for metabolic uptake and impact on vegetation and ecosystems is through the rhizosphere. PM deposited directly to the soil can influence nutrient cycling, especially that of nitrogen, through its effects on the rhizosphere bacteria and fungi. Alkaline cation and aluminum availability are dependent upon the pH of the soil that may be altered dramatically by deposition of various classes of PM. A regional effect of PM on ecosystems is linked to climate change. Increased PM may reduce radiation interception by plant canopies and may reduce precipitation through a variety of physical effects. At the present time, evidence does not support large regional threats due to un-speciated PM, though site-specific and constituent-specific effects can be readily identified. Interactions of PM with other pollutants and with components of climate change remain important areas of research in assessment of challenges to ecosystem stability.

  8. Particulate emissions from construction activities.

    PubMed

    Muleski, Gregory E; Cowherd, Chatten; Kinsey, John S

    2005-06-01

    Although it has long been recognized that road and building construction activity constitutes an important source of particulate matter (PM) emissions throughout the United States, until recently only limited research has been directed to its characterization. This paper presents the results of PM10 and PM2.5 (particles < or = 10 microm and < or = 2.5 microm in aerodynamic diameter, respectively) emission factor development from the onsite testing of component operations at actual construction sites during the period 1998-2001. Much of the testing effort was directed at earthmoving operations with scrapers, because earthmoving is the most important contributor of PM emissions across the construction industry. Other sources tested were truck loading and dumping of crushed rock and mud and dirt carryout from construction site access points onto adjacent public paved roads. Also tested were the effects of watering for control of scraper travel routes and the use of paved and graveled aprons at construction site access points for reducing mud and dirt carryout. The PM10 emissions from earthmoving were found to be up to an order of magnitude greater than predicted by AP-42 emission factors drawn from other industries. As expected, the observed PM2.5:PM10 emission factor ratios reflected the relative importance of the vehicle exhaust and the resuspended dust components of each type of construction activity. An unexpected finding was that PM2.5 emissions from mud and dirt carryout were much less than anticipated. Finally, the control efficiency of watering of scraper travel routes was found to closely follow a bilinear moisture model.

  9. Review of PAR parameterizations in ocean ecosystem models

    NASA Astrophysics Data System (ADS)

    Byun, Do-Seong; Wang, Xiao Hua; Hart, Deirdre E.; Zavatarelli, Marco

    2014-12-01

    Commonly-used empirical equations for calculating downward 'photosynthetically available radiation' or PAR were reviewed in order to identify a more theoretically-sound parameterization for application to ocean biogeochemical models. Three different forms of broadband PAR parameterization are currently employed in biogeochemical models, each of them originating from the downward irradiance formulations normally applied to ocean circulation models, which produce poor attenuation estimates for PAR. Two of the PAR formulations, a single-exponential function and a double-exponential function, are parameterized by multiplying surface irradiance by a coefficient determining the portion of underwater PAR. The third formulation uses the second term of the double-exponential function. After elucidating the theoretical problems of modeling PAR using these parameterizations, we suggest an improved, R-modified double-exponential PAR formulation, including Paulson and Simpson's (1977) parameter values. We also newly estimate PAR penetration via least-squares fitting of values digitized from Jerlov's (1976) observations in different oceanic water types, and compare this PAR-observation derived parameterization with our new, theoretical, R-modified parameterization. Finally, we discuss a universal limitation inherent in current theoretical approaches to PAR parameterization.

  10. Modelisation par elements finis du muscle strie

    NASA Astrophysics Data System (ADS)

    Leonard, Mathieu

    Ce present projet de recherche a permis. de creer un modele par elements finis du muscle strie humain dans le but d'etudier les mecanismes engendrant les lesions musculaires traumatiques. Ce modele constitue une plate-forme numerique capable de discerner l'influence des proprietes mecaniques des fascias et de la cellule musculaire sur le comportement dynamique du muscle lors d'une contraction excentrique, notamment le module de Young et le module de cisaillement de la couche de tissu conjonctif, l'orientation des fibres de collagene de cette membrane et le coefficient de poisson du muscle. La caracterisation experimentale in vitro de ces parametres pour des vitesses de deformation elevees a partir de muscles stries humains actifs est essentielle pour l'etude de lesions musculaires traumatiques. Le modele numerique developpe est capable de modeliser la contraction musculaire comme une transition de phase de la cellule musculaire par un changement de raideur et de volume a l'aide des lois de comportement de materiau predefinies dans le logiciel LS-DYNA (v971, Livermore Software Technology Corporation, Livermore, CA, USA). Le present projet de recherche introduit donc un phenomene physiologique qui pourrait expliquer des blessures musculaires courantes (crampes, courbatures, claquages, etc.), mais aussi des maladies ou desordres touchant le tissu conjonctif comme les collagenoses et la dystrophie musculaire. La predominance de blessures musculaires lors de contractions excentriques est egalement exposee. Le modele developpe dans ce projet de recherche met ainsi a l'avant-scene le concept de transition de phase ouvrant la porte au developpement de nouvelles technologies pour l'activation musculaire chez les personnes atteintes de paraplegie ou de muscles artificiels compacts pour l'elaboration de protheses ou d'exosquelettes. Mots-cles Muscle strie, lesion musculaire, fascia, contraction excentrique, modele par elements finis, transition de phase

  11. Small-angle light scattering by airborne particulates: Environnement S.A. continuous particulate monitor

    NASA Astrophysics Data System (ADS)

    Renard, Jean-Baptiste; Thaury, Claire; Mineau, Jean-Luc; Gaubicher, Bertrand

    2010-08-01

    Airborne particulate matter may have an effect on human health. It is therefore necessary to determine and control in real time the evolution of the concentration and mass of particulates in the ambient air. These parameters can be obtained using optical methods. We propose here a new instrument, 'CPM' (continuous particulate monitor), for the measurement of light scattered by ambient particulates at small angles. This geometry allows simultaneous and separate detections of PM10, PM2.5 and PM1 fractions of airborne particulate matter, with no influence of their chemical nature and without using theoretical calculations. The ambient air is collected through a standard sampling head (PM10 inlet according to EN 12341, PM2.5 inlet according to EN 14907; or PM1, TSP inlets, standard US EPA inlets). The analysis of the first measurements demonstrates that this new instrument can detect, for each of the seven defined size ranges, real-time variations of particulate content in the ambient air. The measured concentrations (expressed in number per liter) can be converted into total mass concentrations (expressed in micrograms per cubic meter) of all fractions of airborne particulate matters sampled by the system. Periodic comparison with a beta-attenuation mass monitor (MP101M Beta Gauge Analyzer from Environnement S.A. company) allows the calculation of a calibration factor as a function of the mean particulate density that is used for this conversion. It is then possible to provide real-time relative variations of aerosol mass concentration.

  12. Advanced Hybrid Particulate Collector Project Management Plan

    SciTech Connect

    Miller, S.J.

    1995-11-01

    As the consumption of energy increases, its impact on ambient air quality has become a significant concern. Recent studies indicate that fine particles from coal combustion cause health problems as well as atmospheric visibility impairment. These problems are further compounded by the concentration of hazardous trace elements such as mercury, cadmium, selenium, and arsenic in fine particles. Therefore, a current need exists to develop superior, but economical, methods to control emissions of fine particles. Since most of the toxic metals present in coal will be in particulate form, a high level of fine- particle collection appears to be the best method of overall air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and cannot be collected in particulate control devices. Therefore, this project will focus on developing technology not only to provide ultrahigh collection efficiency of particulate air toxic emissions, but also to capture vapor- phase trace metals such as mercury and selenium. Currently, the primary state-of-the-art technologies for particulate control are fabric filters (baghouses) and electrostatic precipitators (ESPs). However, they both have limitations that prevent them from achieving ultrahigh collection of fine particulate matter and vapor-phase trace metals. The objective of this project is to develop a highly reliable advanced hybrid particulate collector (AHPC) that can provide > 99.99 % particulate collection efficiency for all particle sizes between 0.01 and 50 14m, is applicable for use with all U.S. coals, and is cost-0443competitive with existing technologies. Phase I of the project is organized into three tasks: Task I - Project Management, Reporting, and Subcontract Consulting Task 2 - Modeling, Design, and Construction of 200-acfm AHPC Model Task 3 - Experimental Testing and Subcontract Consulting

  13. A Conserved Mode of Protein Recognition and Binding in a ParD−ParE Toxin−Antitoxin Complex

    SciTech Connect

    Dalton, Kevin M.; Crosson, Sean

    2010-05-06

    Toxin-antitoxin (TA) systems form a ubiquitous class of prokaryotic proteins with functional roles in plasmid inheritance, environmental stress response, and cell development. ParDE family TA systems are broadly conserved on plasmids and bacterial chromosomes and have been well characterized as genetic elements that promote stable plasmid inheritance. We present a crystal structure of a chromosomally encoded ParD-ParE complex from Caulobacter crescentus at 2.6 {angstrom} resolution. This TA system forms an {alpha}{sub 2}{beta}{sub 2} heterotetramer in the crystal and in solution. The toxin-antitoxin binding interface reveals extensive polar and hydrophobic contacts of ParD antitoxin helices with a conserved recognition and binding groove on the ParE toxin. A cross-species comparison of this complex structure with related toxin structures identified an antitoxin recognition and binding subdomain that is conserved between distantly related members of the RelE/ParE toxin superfamily despite a low level of overall primary sequence identity. We further demonstrate that ParD antitoxin is dimeric, stably folded, and largely helical when not bound to ParE toxin. Thus, the paradigmatic model in which antitoxin undergoes a disorder-to-order transition upon toxin binding does not apply to this chromosomal ParD-ParE TA system.

  14. Contribution aux Methodes Analytiques des Substances a L'aide de Faisceaux de Particules Chargees

    NASA Astrophysics Data System (ADS)

    Saidi, Abdelmajid

    Nous avons vu les possibilites d'analyse par particules chargees des aerosols recueillis sur des filtres de type MILLIPORE. La meme technique a ete utilisee pour des filtres ayant servi a la filtration de l'eau du fleuve Saint-laurent. Deux techniques ont ete utilisees: (1) FAST (Forward Alpha Scattering Technique): pour analyser l'hydrogene, le carbone, l'oxygene et puis l'azote. Des alpha de 12 MeV ont ete utilises. (2) PIXE (Particle Induced X-ray Emission): pour analyser les elements moyens et lourds, dans ce cas des protons de 3 MeV ainsi que des ions d'argon de 1 et 1.6 MeV ont ete utilises. Les etudes ont montre que sous vide, la majorite des problemes proviennent des dommages causes par l'echauffement du a l'impact du faisceau sur le filtre. L'analyse quantitative par l'intermediaire du faisceau extrait peut presenter des difficultes en ce qui concerne les elements legers pour lesquels l'absorption des rayonnements caracteristiques dans l'atmosphere externe est importante. Les ions lourds se pretent mal aux analyses des aerosols du fait de leur limite de sensibilite. L'analyse directe de liquides par des protons est particulierement interessante puisqu'elle ne necessite aucune preparation prealable des echantillons. A cet effet, un programme de calcul de concentration des elements dans la solution a analyser a ete mis au point. Nous avons determine la limite de sensibilite de la methode PIXE pour les cibles minces (filtre) et pour le cas ou la matrice est de l'eau. Enfin, la technique FAST peut etre un complement de la technique PIXE.

  15. Comparison of particulate verification techniques study

    NASA Astrophysics Data System (ADS)

    Rivera, Rachel

    2006-08-01

    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 on the coupons and was used to establish a baseline, or basis of comparison, against the five techniques that were studied. The five particulate verification techniques were the Tapelift, the Particulate Solvent Rinse, the GelPak lift, an in-line vacuum filtration probe, and the Infinity Focusing Microscope (IFM). The four types of materials consisted of magnesium flouride (MgF II) coated mirrors, composite coated silver aluminum (CCAg), Z93 and NS43G coated aluminum, and silicon (si) wafers. The vacuum probe was determined to be most effective for Z93, the tapelift or vacuum probe for MgF2, and the GelPak Lift for CCAg and si substrates. A margin of error for each technique, based on experimental data from two experiments, for si wafer substrates, yielded the following: Tapelift - 67%, Solvent Rinse - 58%, GelPak- 26%, Vacuum Probe - 93%, IFM-to be determined.

  16. A new model for estimating boreal forest fPAR

    NASA Astrophysics Data System (ADS)

    Majasalmi, Titta; Rautiainen, Miina; Stenberg, Pauline

    2014-05-01

    Life on Earth is continuously sustained by the extraterrestrial flux of photosynthetically active radiation (PAR, 400-700 nm) from the sun. This flux is converted to biomass by chloroplasts in green vegetation. Thus, the fraction of absorbed PAR (fPAR) is a key parameter used in carbon balance studies, and is listed as one of the Essential Climate Variables (ECV). Temporal courses of fPAR for boreal forests are difficult to measure, because of the complex 3D structures. Thus, they are most often estimated based on models which quantify the dependency of absorbed radiation on canopy structure. In this study, we adapted a physically-based canopy radiation model into a fPAR model, and compared modeled and measured fPAR in structurally different boreal forest stands. The model is based on the spectral invariants theory, and uses leaf area index (LAI), canopy gap fractions and spectra of foliage and understory as input data. The model differs from previously developed more detailed fPAR models in that the complex 3D structure of coniferous forests is described using an aggregated canopy parameter - photon recollision probability p. The strength of the model is that all model inputs are measurable or available through other simple models. First, the model was validated with measurements of instantaneous fPAR obtained with the TRAC instrument in nine Scots pine, Norway spruce and Silver birch stands in a boreal forest in southern Finland. Good agreement was found between modeled and measured fPAR. Next, we applied the model to predict temporal courses of fPAR using data on incoming radiation from a nearby flux tower and sky irradiance models. Application of the model to simulate diurnal and seasonal values of fPAR indicated that the ratio of direct-to-total incident radiation and leaf area index are the key factors behind the magnitude and variation of stand-level fPAR values.

  17. 2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) ...

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

    2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) BARRACKS WITH RADAR ATTACHED. - Nike Hercules Missile Battery Summit Site, Battery Control Administration & Barracks Building, Anchorage, Anchorage, AK

  18. Method for dispersing catalyst onto particulate material

    DOEpatents

    Utz, Bruce R.; Cugini, Anthony V.

    1992-01-01

    A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

  19. PRODUCTION OF SHEET FROM PARTICULATE MATERIAL

    DOEpatents

    Blainey, A.

    1959-05-12

    A process is presented for forming coherent sheet material from particulate material such as granular or powdered metal, granular or powdered oxide, slurries, pastes, and plastic mixes which cohere under pressure. The primary object is to avoid the use of expensive and/ or short lived pressing tools, that is, dies and specially profiled rolls, and so to reduce the cost of the product and to prcvide in a simple manner for the making of the product in a variety of shapes or sizes. The sheet material is formed when the particulate material is laterally confined in a boundary material deformable in all lateral directions under axial pressure and then axially compressing the layer of particulate material together with the boundary material.

  20. Thermogravimetric analysis of diesel particulate matter

    NASA Astrophysics Data System (ADS)

    Lapuerta, M.; Ballesteros, R.; Rodríguez-Fernández, J.

    2007-03-01

    The regulated level of diesel particulate mass for 2008 light-duty diesel on-road engines will be 0.005 g km-1 in Europe. Measurements by weighing and analysis of this low level of particulate mass based on chemical extraction are costly, time consuming and hazardous because of the use of organic solvents, potentially carcinogenic. An alternative to this analysis is proposed here: a thermal mass analyser that measures the volatile fraction (VOF) as well as the soot fraction of the particulate matter (PM) collected on a cleaned fibre glass filter. This paper evaluates this new thermal mass measurement (TGA) as a possible alternative to the conventional chemical extraction method, and presents the results obtained with both methods when testing a diesel engine fuelled with a reference diesel fuel (REF), a pure biodiesel fuel (B100) and two blends with 30% and 70% v/v biodiesel (B30 and B70, respectively).

  1. Etude de L'energie Moyenne de Creation de Paire dans les Detecteurs de Particules AU Silicium Amorphe Hydrogene

    NASA Astrophysics Data System (ADS)

    Dubeau, Jacques

    Ce travail porte sur la mesure et le calcul de l'energie de creation d'une paire electron-trou, epsilon_{p}, par une particule ionisante dans des detecteurs en couches minces au a-Si:H. Cette etude fut realisee a l'aide de dispositifs specialement concus et qui sont de deux types. Le premier emprunte au domaine des cellules photovoltaiques des structures p/i/n qui ont des couches dopees de ~30 nm mais dont on augmente l'epaisseur de la couche sensible, la couche i, a 3 ou 4 mum. Ces dispositifs peuvent etre polarises en inverse jusqu'a 20 V/ mum. Le second type consiste aussi en des structures p/i/n qui cette fois sont adaptees specialement aux applications de detection. Ces nouveaux dispositifs possedent une couche p de plus de 300 nm qui attenue l'injection d'electrons lors de l'application de la tension inverse, prevenant ainsi le claquage premature et permettant l'application de tensions de plus de 60 V/mum. De plus, ils ont une couche i faisant de 4 a 18 mu m. Nous avons soumis ces dispositifs a des protons et des particules alpha couvrant un domaine de dE/dx de 7.5 a 300 keV/mum. On met ainsi en evidence deux regimes d'operations. Premierement, lorsqu'on utilise des particules ayant des dE/dx eleves, a des incidences normales a la surface du detecteur et que la tension appliquee aux bornes du dispositif est faible, le signal est fortement attenue par des effets plasmas. Deuxiemement, a de fortes tensions pour des particules a incidences obliques et dE/dx faibles, l'amplitude du signal est proportionnelle a l'energie deposee dans la zone i du detecteur. Cependant, ce signal n'est pas sature et il semble augmenter avec la tension au-dela de la tension de claquage. De plus, on demontre qu'a des tensions intermediaires le signal est plus eleve si la tension est pulsee et si le temps d'integration de l'electronique est long (~ 20mus). En extrapolant l'amplitude du signal a une tension infinie nous obtenons une valeur de epsilon _{p} affranchie de tout effet de

  2. Particulate matter sensor with a heater

    DOEpatents

    Hall, Matthew

    2011-08-16

    An apparatus to detect particulate matter. The apparatus includes a sensor electrode, a shroud, and a heater. The electrode measures a chemical composition within an exhaust stream. The shroud surrounds at least a portion of the sensor electrode, exclusive of a distal end of the sensor electrode exposed to the exhaust stream. The shroud defines an air gap between the sensor electrode and the shroud and an opening toward the distal end of the sensor electrode. The heater is mounted relative to the sensor electrode. The heater burns off particulate matter in the air gap between the sensor electrode and the shroud.

  3. Much ado about dioxides and particulates

    SciTech Connect

    Doane, F.P.

    1980-02-01

    Technical feature: The effect of carbon dioxide on climate is uncertain, and recent high CO2 levels may not persist. Worldwide warming trends since 1840 are outlined. There is no conclusive evidence that increased burning of fossil fuels has had or will have any ill effect on the climate. While there has been a slight increase in the CO2 content of the atmosphere, the oxidation of humus and bogs rather than fossil fuels seems to be the main source of increased atmospheric CO2 and particulates. Increased plant growth and adsorption of CO2 and particulates by the oceans will maintain an even balance in the atmosphere. (17 references, 2 tables)

  4. Particulate hot gas stream cleanup technical issues

    SciTech Connect

    Pontius, D.H.; Snyder, T.R.

    1999-09-30

    The analyses of hot gas stream cleanup particulate samples and descriptions of filter performance studied under this contract were designed to address problems with filter operation that have been linked to characteristics of the collected particulate matter. One objective of this work was to generate an interactive, computerized data bank of the key physical and chemical characteristics of ash and char collected from operating advanced particle filters and to relate these characteristics to the operation and performance of these filters. The interactive data bank summarizes analyses of over 160 ash and char samples from fifteen pressurized fluidized-bed combustion and gasification facilities utilizing high-temperature, high pressure barrier filters.

  5. Method of dispersing particulate aerosol tracer

    DOEpatents

    O'Holleran, Thomas P.

    1988-01-01

    A particulate aerosol tracer which comprises a particulate carrier of sheet silicate composition having a particle size up to one micron, and a cationic dopant chemically absorbed in solid solution in the carrier. The carrier is preferably selected from the group consisting of natural mineral clays such as bentonite, and the dopant is selected from the group consisting of rare earth elements and transition elements. The tracers are dispersed by forming an aqueous salt solution with the dopant present as cations, dispersing the carriers in the solution, and then atomizing the solution under heat sufficient to superheat the solution droplets at a level sufficient to prevent reagglomeration of the carrier particles.

  6. Modeling of Particulate Behavior in Pinhole Breaches

    SciTech Connect

    Casella, Andrew M.; Loyalka, Sudarshan K.; Hanson, Brady D.

    2014-04-01

    A model is presented for calculating depressurization time for and particulate release from used nuclear fuel dry storage containers that have developed a pinhole breach. Particular attention is given to particulate deposition and transmission within the breach pathway. The model is modular in nature and is developed in a way that allows for more advanced treatments of internal temperature, internal component geometry, or aerosol flow to be readily incorporated. The model can be treated as a basis for addressing concerns associated with monitoring and verification efforts during long-term dry cask storage

  7. Particulate carbon in Los Angeles air.

    PubMed

    Grosjean, D

    1984-01-13

    A selective combustion method has been applied to the determination of total, organic and elemental particulate carbon in Los Angeles air. Carbon concentrations (10-56 micrograms m-3) and their temporal variations are presented for multiday smog episodes. Organic carbon/elemental carbon concentration ratios ranged from approximately 3 during the winter months to approximately 10 during the smog season. Photochemical production of particulate organic carbon is estimated to be approximately 76-118 X 10(3) kg/day, as compared to approximately 31 X 10(3) kg/day from direct emissions. This estimate is also consistent with gas-to-particle conversion considerations for precursor hydrocarbons.

  8. Microstructure development in particulate ceramic coatings

    SciTech Connect

    Kim, Y.J.; Wara, N.M.; Francis, L.F.; Velamakanni, B.V.

    1994-12-31

    Microstructure development in particulate coatings is influenced by the particle-particle interactions and additional mechanisms, such as reaction and phase separation, which are driven by compositional changes in a coating during deposition and drying. The effect of agglomeration rate on microstructure uniformity and pore content is demonstrated using coatings produced from aqueous alumina dispersions. The addition of cellulose acetate and acetone to the alumina dispersion leads to phase separation and a coating with large cylindrical pores. The formation of particles by reactions during deposition is also discussed. The pore content of particulate titania coatings prepared in this way can be varied from 30 to 60% by changing the coating conditions.

  9. [Suspended particulates and lung health].

    PubMed

    Neuberger, Manfred; Moshammer, Hanns

    2004-01-01

    Based on several severe air pollution episodes, a temporal correlation between high concentrations of particulate matter (PM) and SO2 pollution and acute increases in respiratory and cardiopulmonary mortality had been established in Vienna for the 1970's. After air pollution had decreased in Austria in the 1980's--as documented by data on SO2, and total suspended particles (TSP)--no such associations between day-to-day changes of SO2 and TSP and mortality have been documented any more, however, traffic related pollutants like fine particles and NO2 remained a problem. Therefore, short term effects of PM on lung function, morbidity and mortality were investigated in Vienna, Linz, Graz and a rural control area. Long-term exposure and chronic disease--even more important for public health--were studied in repeated cross-sectional, a mixed longitudinal and a birth cohort study on school children in the city of Linz. Lung function growth was found impaired from long-term exposure to air pollutants and improved in districts where ambient air pollution had decreased. Where only TSP and SO2 had decreased, no continuous improvement of small airway function was found and end-expiratory flow rates stayed impaired where NO2-reduction from technical improvements of cars and industry was counterbalanced by increase of motorized (diesel) traffic. Remaining acute effects of ambient air pollution in 2001 from PM, NO2 and co-pollutants found in a time series study also show that continuing efforts are necessary. Active surface of particles inhaled several hours to days before spirometry was found related to short-term reductions in forced vital capacity-FVC (p<0.01), forced expiratory volume in one second-FEV1 (p<0.01) and maximal expiratory flow rate at 50% of vital capacity-MEF50 (p<0.05). In pupils with asthma or previous airway obstruction 4-week-diaries proved that the following symptoms increased with acute exposure to higher active surface of particles: wheezing (p<0

  10. Taare Zameen Par and dyslexic savants

    PubMed Central

    Chakravarty, Ambar

    2009-01-01

    The film Taare Zameen Par (Stars upon the Ground) portrays the tormented life at school and at home of a child with dyslexia and his eventual success after his artistic talents are discovered by his art teacher at the boarding school. The film hints at a curious neurocognitive phenomenon of creativity in the midst of language disability, as exemplified in the lives of people like Leonardo da Vinci and Albert Einstein, both of whom demonstrated extraordinary creativity even though they were probably affected with developmental learning disorders. It has been hypothesized that a developmental delay in the dominant hemisphere most likely ‘disinhibits’ the nondominant parietal lobe, unmasking talents—artistic or otherwise—in some such individuals. It has been suggested that, in remedial training, children with learning disorders be encouraged to develop such hidden talents to full capacity, rather than be subjected to the usual overemphasis on the correction of the disturbed coded symbol operations. PMID:20142854

  11. 40 CFR 230.21 - Suspended particulates/turbidity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles...

  12. 40 CFR 230.21 - Suspended particulates/turbidity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles...

  13. 40 CFR 230.21 - Suspended particulates/turbidity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles...

  14. 40 CFR 230.21 - Suspended particulates/turbidity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles...

  15. 40 CFR 230.21 - Suspended particulates/turbidity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles...

  16. Transcriptome profiling reveals links between ParS/ParR, MexEF-OprN, and quorum sensing in the regulation of adaptation and virulence in Pseudomonas aeruginosa

    PubMed Central

    2013-01-01

    Background The ParS/ParR two component regulatory system plays critical roles for multidrug resistance in Pseudomonas aeruginosa. It was demonstrated that in the presence of antimicrobials, ParR enhances bacterial survival by distinct mechanisms including activation of the mexXY efflux genes, enhancement of lipopolysaccharide modification through the arn operon, and reduction of the expression of oprD porin. Results In this study, we report on transcriptomic analyses of P. aeruginosa PAO1 wild type and parS and parR mutants growing in a defined minimal medium. Our transcriptomic analysis provides the first estimates of transcript abundance for the 5570 coding genes in P. aeruginosa PAO1. Comparative transcriptomics of P. aeruginosa PAO1 and par mutants identified a total of 464 genes regulated by ParS and ParR. Results also showed that mutations in the parS/parR system abolished expression of the mexEF-oprN operon by down-regulating the regulatory gene mexS. In addition to the known effects on drug resistance genes, transcript abundances of the quorum sensing genes (rhlIR and pqsABCDE-phnAB) were higher in both parS and parR mutants. In accordance with these results, a significant portion of the ParS/ParR regulated genes belonged to the MexEF-OprN and quorum sensing regulons. Deletion of the par genes also led to increased phenazine production and swarming motility, consistent with the up-regulation of the phenazine and rhamnolipid biosynthetic genes, respectively. Conclusion Our results link the ParS/ParR two component signal transduction system to MexEF-OprN and quorum sensing systems in P. aeruginosa. These results expand our understanding of the roles of the ParS/ParR system in the regulation of gene expression in P. aeruginosa, especially in the absence of antimicrobials. PMID:24034668

  17. 76 FR 5270 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Particulate Matter...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-31

    ... particulates can cause heart and lung disease. Particulate matter also aggravates asthma. Airborne particulate... more for fine particulates. WPC states that it would be difficult for sources to limit PM 2.5...

  18. TMS suppression of right pars triangularis, but not pars opercularis, improves naming in aphasia

    PubMed Central

    Naeser, Margaret A.; Martin, Paula I.; Theoret, Hugo; Kobayashi, Masahito; Fregni, Felipe; Nicholas, Marjorie; Tormos, Jose M.; Steven, Megan S.; Baker, Errol H.; Pascual-Leone, Alvaro

    2011-01-01

    This study sought to discover if an optimum 1 cm2 area in the non-damaged right hemisphere (RH) was present, which could temporarily improve naming in chronic, nonfluent aphasia patients when suppressed with repetitive transcranial magnetic stimulation (rTMS). Ten minutes of slow, 1 Hz rTMS was applied to suppress different RH ROIs in eight aphasia cases. Picture naming and response time (RT) were examined before, and immediately after rTMS. In aphasia patients, suppression of right pars triangularis (PTr) led to significant increase in pictures named, and significant decrease in RT. Suppression of right pars opercularis (POp), however, led to significant increase in RT, but no change in number of pictures named. Eight normals named all pictures correctly; similar to aphasia patients, RT significantly decreased following rTMS to suppress right PTr, versus right POp. Differential effects following suppression of right PTr versus right POp suggest different functional roles for these regions. PMID:21864891

  19. Tumour-suppression activity of the proapoptotic regulator Par4.

    PubMed

    García-Cao, Isabel; Duran, Angeles; Collado, Manuel; Carrascosa, Maria J; Martín-Caballero, Juan; Flores, Juana M; Diaz-Meco, Maria T; Moscat, Jorge; Serrano, Manuel

    2005-06-01

    The proapoptotic protein encoded by Par4 (prostate apoptosis response 4) has been implicated in tumour suppression, particularly in the prostate. We report here that Par4-null mice are prone to develop tumours, both spontaneously and on carcinogenic treatment. The endometrium and prostate of Par4-null mice were particularly sensitive to the development of proliferative lesions. Most (80%) Par4-null females presented endometrial hyperplasia by 9 months of age, and a significant proportion (36%) developed endometrial adenocarcinomas after 1 year of age. Similarly, Par4-null males showed a high incidence of prostate hyperplasia and prostatic intraepithelial neoplasias, and were extraordinarily sensitive to testosterone-induced prostate hyperplasia. Finally, the uterus and prostate of young Par4-null mice have increased levels of the apoptosis inhibitor XIAP (X-chromosome-linked inhibitor of apoptosis), supporting the previously proposed function of Par4 as an inhibitor of the (zeta)PKC (atypical protein kinase)-NF-(kappa)B (nuclear factor-(kappa)B)-XIAP pathway. These data show that Par4 has an important role in tumour suppression, with a particular relevance in the endometrium and prostate.

  20. Tumour-suppression activity of the proapoptotic regulator Par4

    PubMed Central

    García-Cao, Isabel; Duran, Angeles; Collado, Manuel; Carrascosa, Maria J.; Martín-Caballero, Juan; Flores, Juana M.; Diaz-Meco, Maria T.; Moscat, Jorge; Serrano, Manuel

    2005-01-01

    The proapoptotic protein encoded by Par4 (prostate apoptosis response 4) has been implicated in tumour suppression, particularly in the prostate. We report here that Par4-null mice are prone to develop tumours, both spontaneously and on carcinogenic treatment. The endometrium and prostate of Par4-null mice were particularly sensitive to the development of proliferative lesions. Most (80%) Par4-null females presented endometrial hyperplasia by 9 months of age, and a significant proportion (36%) developed endometrial adenocarcinomas after 1 year of age. Similarly, Par4-null males showed a high incidence of prostate hyperplasia and prostatic intraepithelial neoplasias, and were extraordinarily sensitive to testosterone-induced prostate hyperplasia. Finally, the uterus and prostate of young Par4-null mice have increased levels of the apoptosis inhibitor XIAP (X-chromosome-linked inhibitor of apoptosis), supporting the previously proposed function of Par4 as an inhibitor of the ζPKC (atypical protein kinase)–NF-κB (nuclear factor-κB)–XIAP pathway. These data show that Par4 has an important role in tumour suppression, with a particular relevance in the endometrium and prostate. PMID:15877079

  1. Cranial particulate bone graft ossifies calvarial defects by osteogenesis.

    PubMed

    Hassanein, Aladdin H; Arany, Praveen R; Couto, Rafael A; Clune, James E; Glowacki, Julie; Rogers, Gary F; Mulliken, John B; Greene, Arin K

    2012-05-01

    Cranial particulate bone graft heals inlay calvarial defects and can be harvested as early as infancy. The purpose of this study was to test the hypothesis that particulate bone promotes ossification primarily by osteogenesis. Freshly harvested particulate bone, devitalized particulate bone, and high-speed drilled bone dust from rabbit calvaria were assayed for metabolic activity (resazurin) and viable osteoblasts (alkaline phosphatase). A rabbit cranial defect model was used to test the effect of devitalizing particulate bone on in vivo ossification. A parietal critical-size defect was created and managed in three ways: (1) no implant (n = 6); (2) particulate bone implant (n = 6); and (3) devitalized particulate bone implant (n = 6). Micro-computed tomographic scanning was used to measure ossification 16 weeks later; histology also was studied. Particulate bone contained more viable cells (0.94 percent transmittance per milligram) compared with devitalized particulate bone (0.007 percent) or bone dust (0.21 percent) (p = 0.01). Particulate bone had greater alkaline phosphatase activity (0.13 μU/μg) than devitalized particulate bone (0.000) or bone dust (0.06) (p = 0.01). Critical-size defects treated with particulate bone had more ossification (99.7 percent) compared with devitalized particulate bone implants (42.2 percent) (p = 0.01); no difference was found between devitalized particulate bone and the control (40.8 percent) (p = 0.9). Particulate bone graft contains living cells, including osteoblasts, that are required to heal critical-size cranial defects. These data support the hypothesis that particulate bone promotes ossification primarily by osteogenesis.

  2. FINE PARTICULATE MATTER EMISSIONS FROM CANDLES

    EPA Science Inventory

    The paper gives reulst of testing five types of candles, purchased from local stores, for fine particulate matter (PM) emissions under close-to-realistic conditions in a research house. The test method allows for determination of both the emission and deposition rates. Most tes...

  3. Miniature Sensors for Airborne Particulate Matter

    EPA Science Inventory

    Our group is working to design a small,lightweight, low-cost real-time particulate matter(PM) sensor to enable better monitoring of PMconcentrations in air, with the goal of informingpolicymakers and regulators to provide betterpublic health. The sensor reads the massconcentratio...

  4. Control Techniques for Particulate Air Pollutants.

    ERIC Educational Resources Information Center

    National Air Pollution Control Administration (DHEW), Washington, DC.

    Included is a comprehensive review of the approaches commonly recommended for controlling the sources of particulate air pollution. Not all possible combinations of control techniques that might bring about more stringent control of each individual source are reviewed. The many agricultural, commercial, domestic, industrial, and municipal…

  5. SPATIAL PREDICTION OF FINE PARTICULATE MATTER

    EPA Science Inventory

    A new national monitoring network for the measurement of fine particular matter (PM2.5) is currently under development. A primary goal of this network is to collect monitoring data in residential communities for the evaluation of compliance with particulate air quality standards...

  6. REINVENTING PERSONAL EXPOSURE TO PARTICULATE MATTER

    EPA Science Inventory

    Recent epidemiologic studies of modern air pollution show statistically significant relationships between fluctuations of daily non-trauma mortality and fluctuations of daily ambient particulate matter (PM) levels at low concentrations. A review of historic smoke-fog (smog)episo...

  7. Particulate control system for biomass firing technologies

    SciTech Connect

    Easom, B.H.; Smolensky, L.A.; Wysk, S.R.

    1996-12-31

    The new particulate control equipment, the so-called Core Separator, overcomes most of the limitations inherent in conventional particulate control systems and can be effectively adapted for biomass applications. The Core Separator is a mechanical collector; however, this technology overcomes the performance limitation inherent in cyclones by performing the tasks of separation and collection in two separate components. The separation process is less affected by secondary flows and is much more efficient than the collection process. Also, the components of the system are arranged in such a way that the separation process determines the system efficiency. As a result, particulate emission rates downstream of this system are one fourth of those from the most efficient cyclones. This technology has been demonstrated through commercial unit installations in the U.S. and abroad. It has been used for industrial separations including coal fly ash, minerals, and chemical recovery applications. It is considered a lower-cost alternative to fabric filters and electrostatic precipitators, albeit one that can meet or exceed regulations for particulate emissions. Development of this technology has been funded by the U.S. Department of Energy, Environmental Protection Agency, and Electric Power Research Institute.

  8. Atmospheric particulate measurements in Norfolk, Virginia

    NASA Technical Reports Server (NTRS)

    Storey, R. W., Jr.; Sentell, R. J.; Woods, D. C.; Smith, J. R.; Harris, F. S., Jr.

    1975-01-01

    Characterization of atmospheric particulates was conducted at a site near the center of Norfolk, Virginia. Air quality was measured in terms of atmospheric mass loading, particle size distribution, and particulate elemental composition for a period of 2 weeks. The objectives of this study were (1) to establish a mean level of air quality and deviations about this mean, (2) to ascertain diurnal changes or special events in air quality, and (3) to evaluate instrumentation and sampling schedules. Simultaneous measurements were made with the following instruments: a quartz crystal microbalance particulate monitor, a light-scattering multirange particle counter, a high-volume air sampler, and polycarbonate membrane filters. To assess the impact of meteorological conditions on air quality variations, continuous data on temperature, relative humidity, wind speed, and wind direction were recorded. Particulate elemental composition was obtained from neutron activation and scanning electron microscopy analyses of polycarbonate membrane filter samples. The measured average mass loading agrees reasonably well with the mass loadings determined by the Virginia State Air Pollution Control Board. There are consistent diurnal increases in atmospheric mass loading in the early morning and a sample time resolution of 1/2 hour seems necessary to detect most of the significant events.

  9. REINVENTING PERSONAL EXPOSURE TO PARTICULATE MATTER

    EPA Science Inventory

    Recent epidemiologic studies of modern air pollution show statistically significant relationships between fluctuations of daily non-trauma mortality and fluctuations of daily ambient particulate matter (PM) levels at low concentrations. A review of historic smoke-fog (smog)episo...

  10. Miniature Sensors for Airborne Particulate Matter

    EPA Science Inventory

    Our group is working to design a small,lightweight, low-cost real-time particulate matter(PM) sensor to enable better monitoring of PMconcentrations in air, with the goal of informingpolicymakers and regulators to provide betterpublic health. The sensor reads the massconcentratio...

  11. Indoor particulate reactive oxygen species concentrations.

    PubMed

    Khurshid, Shahana S; Siegel, Jeffrey A; Kinney, Kerry A

    2014-07-01

    Despite the fact that precursors to reactive oxygen species (ROS) are prevalent indoors, the concentration of ROS inside buildings is unknown. ROS on PM2.5 was measured inside and outside twelve residential buildings and eleven institutional and retail buildings. The mean (± s.d.) concentration of ROS on PM2.5 inside homes (1.37 ± 1.2 nmoles/m(3)) was not significantly different from the outdoor concentration (1.41 ± 1.0 nmoles/m(3)). Similarly, the indoor and outdoor concentrations of ROS on PM2.5 at institutional buildings (1.16 ± 0.38 nmoles/m(3) indoors and 1.68 ± 1.3 nmoles/m(3) outdoors) and retail stores (1.09 ± 0.93 nmoles/m(3) indoors and 1.12 ± 1.1 nmoles/m(3) outdoors) were not significantly different and were comparable to those in residential buildings. The indoor concentration of particulate ROS cannot be predicted based on the measurement of other common indoor pollutants, indicating that it is important to separately assess the concentration of particulate ROS in air quality studies. Daytime indoor occupational and residential exposure to particulate ROS dominates daytime outdoor exposure to particulate ROS. These findings highlight the need for further study of ROS in indoor microenvironments. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. FINE PARTICULATE MATTER EMISSIONS FROM CANDLES

    EPA Science Inventory

    The paper gives reulst of testing five types of candles, purchased from local stores, for fine particulate matter (PM) emissions under close-to-realistic conditions in a research house. The test method allows for determination of both the emission and deposition rates. Most tes...

  13. Holographic Investigation of Solid Propellant Particulates.

    DTIC Science & Technology

    1981-12-01

    Science and Engineering Ii ABSTRACT This investigation completed the development process to establish a technique to obtain holographic recordings of...13 C. EXPERIMENTAL TECHNIQUE --------------------------------- 20 0. DISCUSSION...conditions (pressure, etc.) to the behavior of the particulates within the propellant port and through the nozzle. Four experimental techniques are being

  14. [Around Ambroise Paré: his pupils and friends].

    PubMed

    Dumaître, P

    1996-01-01

    The most important pupil of Paré was Jacques Guillemeau (1550-1613), a famous surgeon from Montpellier. He lived at Paré's during eight years and wrote there his first work "Traité des maladies des yeux" (1585) and was really his "spiritual son". The barber-surgeon Martin Boursier, husband of the famous midwife Louise Bourgeois stayed twenty years with Paré and she learned her practice in his works. Attracted by Paré's fame, Melchior Sebiz (1539-1625) who shall become a famous professor of medicine in Strasbourg attended Paré's lessons and "was with him in great friendship". Among his friends, Thierry de Héry (ca. 1505-ca. 1560), companion of his youth as a barber-surgeon and author of the first French book on syphilis seems to have been the dearest and the nearest to his heart.

  15. 40 CFR 60.182 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.182... Smelters § 60.182 Standard for particulate matter. (a) On and after the date on which the performance test... furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

  16. 40 CFR 60.52 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.52... § 60.52 Standard for particulate matter. (a) On and after the date on which the initial performance... atmosphere from any affected facility any gases which contain particulate matter in excess of 0.18 g/dscm...

  17. 40 CFR 60.122 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.122... Smelters § 60.122 Standard for particulate matter. (a) On and after the date on which the performance test... furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  18. 40 CFR 60.282 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.282... § 60.282 Standard for particulate matter. (a) On and after the date on which the performance test...: (i) Contain particulate matter in excess of 0.10 g/dscm (0.044 gr/dscf) corrected to 8 percent...

  19. 40 CFR 60.92 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.92... Facilities § 60.92 Standard for particulate matter. (a) On and after the date on which the performance test... which: (1) Contain particulate matter in excess of 90 mg/dscm (0.04 gr/dscf). (2) Exhibit 20...

  20. 40 CFR 52.2584 - Control strategy; Particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not...

  1. 40 CFR 60.52 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.52... § 60.52 Standard for particulate matter. (a) On and after the date on which the initial performance... atmosphere from any affected facility any gases which contain particulate matter in excess of 0.18 g/dscm...

  2. 40 CFR 52.427 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) Determination of attainment. EPA has determined, as of May 16, 2012, that based on... fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour PM2.5 national...

  3. 40 CFR 52.2584 - Control strategy; Particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not...

  4. 40 CFR 60.382 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.382... Processing Plants § 60.382 Standard for particulate matter. (a) On and after the date on which the... stack emissions that: (1) Contain particulate matter in excess of 0.05 grams per dry standard...

  5. 40 CFR 60.172 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.172... Smelters § 60.172 Standard for particulate matter. (a) On and after the date on which the performance test... contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  6. 40 CFR 52.427 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) Determination of attainment. EPA has determined, as of May 16, 2012, that based on... fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour PM2.5 national...

  7. 40 CFR 52.1476 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter...

  8. 40 CFR 60.182 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.182... Smelters § 60.182 Standard for particulate matter. (a) On and after the date on which the performance test... furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

  9. 40 CFR 60.402 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.402... Plants § 60.402 Standard for particulate matter. (a) On and after the date on which the performance test... which: (i) Contain particulate matter in excess of 0.030 kilogram per megagram of phosphate rock feed...

  10. 40 CFR 60.292 - Standards for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for particulate matter. 60... Manufacturing Plants § 60.292 Standards for particulate matter. (a) On and after the date on which the..., particulate matter at emission rates exceeding those specified in table CC-1, Column 2 and Column...

  11. 40 CFR 52.1476 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter...

  12. 40 CFR 60.162 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.162... Smelters § 60.162 Standard for particulate matter. (a) On and after the date on which the performance test... particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  13. 40 CFR 60.342 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.342... Manufacturing Plants § 60.342 Standard for particulate matter. (a) On and after the date on which the... gases which: (1) Contain particulate matter in excess of 0.30 kilogram per megagram (0.60 lb/ton)...

  14. 40 CFR 52.2584 - Control strategy; Particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not...

  15. 40 CFR 60.302 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.302... § 60.302 Standard for particulate matter. (a) On and after the 60th day of achieving the maximum... a grain dryer any process emission which: (1) Contains particulate matter in excess of 0.023...

  16. 40 CFR 52.776 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for attainment and maintenance of the secondary standards for particulate matter in...

  17. 40 CFR 60.92 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.92... Facilities § 60.92 Standard for particulate matter. (a) On and after the date on which the performance test... which: (1) Contain particulate matter in excess of 90 mg/dscm (0.04 gr/dscf). (2) Exhibit 20...

  18. 40 CFR 52.2584 - Control strategy; Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not...

  19. 40 CFR 60.162 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.162... Smelters § 60.162 Standard for particulate matter. (a) On and after the date on which the performance test... particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  20. 40 CFR 60.272a - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from...

  1. 40 CFR 60.92 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.92... Facilities § 60.92 Standard for particulate matter. (a) On and after the date on which the performance test... which: (1) Contain particulate matter in excess of 90 mg/dscm (0.04 gr/dscf). (2) Exhibit 20...

  2. 40 CFR 60.292 - Standards for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for particulate matter. 60... Manufacturing Plants § 60.292 Standards for particulate matter. (a) On and after the date on which the..., particulate matter at emission rates exceeding those specified in table CC-1, Column 2 and Column...

  3. 40 CFR 60.682 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.682... Insulation Manufacturing Plants § 60.682 Standard for particulate matter. On and after the date on which the... gases which contain particulate matter in excess of 5.5 kg/Mg (11.0 1b/ton) of glass pulled....

  4. 40 CFR 60.182 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.182... Smelters § 60.182 Standard for particulate matter. (a) On and after the date on which the performance test... furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

  5. 40 CFR 60.282 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.282... § 60.282 Standard for particulate matter. (a) On and after the date on which the performance test...: (i) Contain particulate matter in excess of 0.10 g/dscm (0.044 gr/dscf) corrected to 8 percent...

  6. 40 CFR 60.162 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.162... Smelters § 60.162 Standard for particulate matter. (a) On and after the date on which the performance test... particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  7. 40 CFR 60.92 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.92... Facilities § 60.92 Standard for particulate matter. (a) On and after the date on which the performance test... which: (1) Contain particulate matter in excess of 90 mg/dscm (0.04 gr/dscf). (2) Exhibit 20...

  8. 40 CFR 60.342 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.342... Manufacturing Plants § 60.342 Standard for particulate matter. (a) On and after the date on which the... gases which: (1) Contain particulate matter in excess of 0.30 kilogram per megagram (0.60 lb/ton)...

  9. 40 CFR 60.182 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.182... Smelters § 60.182 Standard for particulate matter. (a) On and after the date on which the performance test... furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

  10. 40 CFR 60.282 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.282... § 60.282 Standard for particulate matter. (a) On and after the date on which the performance test...: (i) Contain particulate matter in excess of 0.10 g/dscm (0.044 gr/dscf) corrected to 8 percent...

  11. 40 CFR 60.682 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.682... Insulation Manufacturing Plants § 60.682 Standard for particulate matter. On and after the date on which the... gases which contain particulate matter in excess of 5.5 kg/Mg (11.0 1b/ton) of glass pulled....

  12. 40 CFR 52.1476 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter...

  13. 40 CFR 52.776 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for attainment and maintenance of the secondary standards for particulate matter in...

  14. 40 CFR 52.1476 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Particulate matter... strategy: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for the attainment and maintenance of the national standards for particulate matter...

  15. 40 CFR 60.172 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.172... Smelters § 60.172 Standard for particulate matter. (a) On and after the date on which the performance test... contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  16. 40 CFR 60.162 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.162... Smelters § 60.162 Standard for particulate matter. (a) On and after the date on which the performance test... particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  17. 40 CFR 60.302 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.302... § 60.302 Standard for particulate matter. (a) On and after the 60th day of achieving the maximum... a grain dryer any process emission which: (1) Contains particulate matter in excess of 0.023...

  18. 40 CFR 60.342 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.342... Manufacturing Plants § 60.342 Standard for particulate matter. (a) On and after the date on which the... gases which: (1) Contain particulate matter in excess of 0.30 kilogram per megagram (0.60 lb/ton)...

  19. 40 CFR 60.402 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.402... Plants § 60.402 Standard for particulate matter. (a) On and after the date on which the performance test... which: (i) Contain particulate matter in excess of 0.030 kilogram per megagram of phosphate rock feed...

  20. 40 CFR 60.282 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.282... § 60.282 Standard for particulate matter. (a) On and after the date on which the performance test...: (i) Contain particulate matter in excess of 0.10 g/dscm (0.044 gr/dscf) corrected to 8 percent...

  1. 40 CFR 52.776 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Particulate matter...: Particulate matter. (a) The requirements of subpart G of this chapter are not met since the plan does not provide for attainment and maintenance of the secondary standards for particulate matter in...

  2. 40 CFR 52.776 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Particulate matter...: Particulate matter. Link to an amendment published at 78 FR 28507, May 15, 2013. (a) The requirements of... the secondary standards for particulate matter in the Metropolitan Indianapolis Intrastate Region....

  3. 40 CFR 60.92 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.92... Facilities § 60.92 Standard for particulate matter. (a) On and after the date on which the performance test... which: (1) Contain particulate matter in excess of 90 mg/dscm (0.04 gr/dscf). (2) Exhibit 20...

  4. 40 CFR 60.302 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.302... § 60.302 Standard for particulate matter. (a) On and after the 60th day of achieving the maximum... a grain dryer any process emission which: (1) Contains particulate matter in excess of 0.023...

  5. 40 CFR 60.52 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.52... § 60.52 Standard for particulate matter. (a) On and after the date on which the initial performance... atmosphere from any affected facility any gases which contain particulate matter in excess of 0.18 g/dscm...

  6. 40 CFR 60.292 - Standards for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for particulate matter. 60... Manufacturing Plants § 60.292 Standards for particulate matter. (a) On and after the date on which the..., particulate matter at emission rates exceeding those specified in table CC-1, Column 2 and Column...

  7. 40 CFR 60.162 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.162... Smelters § 60.162 Standard for particulate matter. (a) On and after the date on which the performance test... particulate matter in excess of 50 mg/dscm (0.022 gr/dscf)....

  8. 40 CFR 52.2059 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... Investigating and Controlling Nontraditional Particulate Matter Emissions Task Completion date Scheduled...

  9. 40 CFR 60.182 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.182... Smelters § 60.182 Standard for particulate matter. (a) On and after the date on which the performance test... furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

  10. 40 CFR 60.302 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.302... § 60.302 Standard for particulate matter. (a) On and after the 60th day of achieving the maximum... a grain dryer any process emission which: (1) Contains particulate matter in excess of 0.023...

  11. 40 CFR 60.52 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.52... § 60.52 Standard for particulate matter. (a) On and after the date on which the initial performance... atmosphere from any affected facility any gases which contain particulate matter in excess of 0.18 g/dscm...

  12. 40 CFR 52.2584 - Control strategy; Particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy; Particulate matter... Control strategy; Particulate matter. (a) Part D—Disapproval—USEPA disapproves Regulation NR 154.11(7)(b... control strategy to attain and maintain the standards for particulate matter, because it does not...

  13. 40 CFR 60.132 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.132... and Bronze Production Plants § 60.132 Standard for particulate matter. (a) On and after the date on... reverberatory furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022...

  14. 40 CFR 60.402 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.402... Plants § 60.402 Standard for particulate matter. (a) On and after the date on which the performance test... which: (i) Contain particulate matter in excess of 0.030 kilogram per megagram of phosphate rock feed...

  15. 40 CFR 60.52 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.52... § 60.52 Standard for particulate matter. (a) On and after the date on which the initial performance... atmosphere from any affected facility any gases which contain particulate matter in excess of 0.18 g/dscm...

  16. 40 CFR 60.682 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.682... Insulation Manufacturing Plants § 60.682 Standard for particulate matter. On and after the date on which the... gases which contain particulate matter in excess of 5.5 kg/Mg (11.0 1b/ton) of glass pulled....

  17. 40 CFR 60.292 - Standards for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for particulate matter. 60... Manufacturing Plants § 60.292 Standards for particulate matter. (a) On and after the date on which the..., particulate matter at emission rates exceeding those specified in table CC-1, Column 2 and Column...

  18. 40 CFR 52.2059 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) (b) EPA approves the PM-10 attainment demonstration for the...-Wilmington, PA-NJ-DE fine particulate matter (PM2.5) nonattainment area has attained the 2006 24-hour...

  19. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... equation for particulate mass emissions then reduces to: ER06OC93.075 (6) Vep = total volume of sample... final reported test results for the mass particulate (Mp) in grams/mile shall be computed as follows. Mp = 0.43(Mp1 + Mp2)/(Dct + Ds) + 0.57(Mp3 + Mp2)/(Dht = Ds) where: (1) Mp1 = Mass of particulate...

  20. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... equation for particulate mass emissions then reduces to: ER06OC93.075 (6) Vep = total volume of sample... final reported test results for the mass particulate (Mp) in grams/mile shall be computed as follows. Mp = 0.43(Mp1 + Mp2)/(Dct + Ds) + 0.57(Mp3 + Mp2)/(Dht = Ds) where: (1) Mp1 = Mass of particulate...

  1. 40 CFR 86.1343-88 - Calculations; particulate exhaust emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... = Weighted mass particulate, grams per brake horsepower-hour. (2) PC = Mass particulate measured during the cold-start test, grams. (3) PH = Mass particulate measured during the hot-start test, grams. (4) BHP-hr..., grams per test phase. (PH = Pmass for the hot-start test and PC = Pmass for the cold-start test....

  2. 40 CFR 86.1343-88 - Calculations; particulate exhaust emissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... = Weighted mass particulate, grams per brake horsepower-hour. (2) PC = Mass particulate measured during the cold-start test, grams. (3) PH = Mass particulate measured during the hot-start test, grams. (4) BHP-hr..., grams per test phase. (PH = Pmass for the hot-start test and PC = Pmass for the cold-start test....

  3. 40 CFR 86.1343-88 - Calculations; particulate exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... = Weighted mass particulate, grams per brake horsepower-hour. (2) PC = Mass particulate measured during the cold-start test, grams. (3) PH = Mass particulate measured during the hot-start test, grams. (4) BHP-hr..., grams per test phase. (PH = Pmass for the hot-start test and PC = Pmass for the cold-start test....

  4. 40 CFR 86.1343-88 - Calculations; particulate exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... = Weighted mass particulate, grams per brake horsepower-hour. (2) PC = Mass particulate measured during the cold-start test, grams. (3) PH = Mass particulate measured during the hot-start test, grams. (4) BHP-hr..., grams per test phase. (PH = Pmass for the hot-start test and PC = Pmass for the cold-start test....

  5. Particulate bioluininescence in dinoflagellates: dissociation and partial reconstitution.

    PubMed

    Fuller, C W; Kreiss, P; Seliger, H H

    1972-09-08

    With the same extraction conditions used for Gonyaulax polyedra, soluble and particulate bioluminescence can be isolated from two additional species, Pyrodinium bahamense and Pyrocystis lunula. We have been able, for all three species, to dissociate soluble luciferin and luciferase from the particulate system. Luciferin can be incorporated into both reacted and unreacted particulate systems.

  6. 40 CFR 52.275 - Particulate matter control.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Particulate matter control. 52.275... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control... particulate matter, and because there is no demonstration that their deletion would not interfere with the...

  7. 40 CFR 60.272a - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...

  8. 40 CFR 60.272a - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...

  9. 40 CFR 60.132 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.132... and Bronze Production Plants § 60.132 Standard for particulate matter. (a) On and after the date on... reverberatory furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf...

  10. 40 CFR 52.275 - Particulate matter control.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Particulate matter control. 52.275... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control... particulate matter, and because there is no demonstration that their deletion would not interfere with the...

  11. 40 CFR 60.122 - Standard for particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for particulate matter. 60.122... Smelters § 60.122 Standard for particulate matter. (a) On and after the date on which the performance test... furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf). (2...

  12. 40 CFR 60.382 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.382... Processing Plants § 60.382 Standard for particulate matter. (a) On and after the date on which the... stack emissions that: (1) Contain particulate matter in excess of 0.05 grams per dry standard cubic...

  13. 40 CFR 60.382 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.382... Processing Plants § 60.382 Standard for particulate matter. (a) On and after the date on which the... stack emissions that: (1) Contain particulate matter in excess of 0.05 grams per dry standard cubic...

  14. 40 CFR 60.122 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.122... Smelters § 60.122 Standard for particulate matter. (a) On and after the date on which the performance test... furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf). (2...

  15. 40 CFR 60.272 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.272... Standard for particulate matter. (a) On and after the date on which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). (2) Exit from a...

  16. 40 CFR 60.132 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.132... and Bronze Production Plants § 60.132 Standard for particulate matter. (a) On and after the date on... reverberatory furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf...

  17. 40 CFR 60.532 - Standards for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for particulate matter. 60... Wood Heaters § 60.532 Standards for particulate matter. Unless exempted under § 60.530, each affected... comply with the following particulate matter emission limits as determined by the test methods and...

  18. 40 CFR 60.132 - Standard for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for particulate matter. 60.132... and Bronze Production Plants § 60.132 Standard for particulate matter. (a) On and after the date on... reverberatory furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf...

  19. 40 CFR 60.132 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.132... and Bronze Production Plants § 60.132 Standard for particulate matter. (a) On and after the date on... reverberatory furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf...

  20. 40 CFR 60.272a - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60... Standard for particulate matter. (a) On and after the date of which the performance test required to be... control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf); (2) Exit from a...

  1. 40 CFR 60.532 - Standards for particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for particulate matter. 60... Wood Heaters § 60.532 Standards for particulate matter. Unless exempted under § 60.530, each affected... comply with the following particulate matter emission limits as determined by the test methods and...

  2. 40 CFR 60.122 - Standard for particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for particulate matter. 60.122... Smelters § 60.122 Standard for particulate matter. (a) On and after the date on which the performance test... furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf). (2...

  3. 40 CFR 52.275 - Particulate matter control.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Particulate matter control. 52.275... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control... particulate matter, and because there is no demonstration that their deletion would not interfere with the...

  4. Urban tree effects on fine particulate matter and human health

    Treesearch

    David J. Nowak

    2014-01-01

    Overall, city trees reduce particulate matter and provide substantial health benefits; but under certain conditions, they can locally increase particulate matter concentrations. Urban foresters need to understand how trees affect particulate matter so they can select proper species and create appropriate designs to improve air quality. This article details trees'...

  5. 40 CFR 60.122 - Standard for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for particulate matter. 60.122... Smelters § 60.122 Standard for particulate matter. (a) On and after the date on which the performance test... furnace any gases which: (1) Contain particulate matter in excess of 50 mg/dscm (0.022 gr/dscf). (2...

  6. 40 CFR 60.532 - Standards for particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for particulate matter. 60... Wood Heaters § 60.532 Standards for particulate matter. Unless exempted under § 60.530, each affected... comply with the following particulate matter emission limits as determined by the test methods and...

  7. 40 CFR 52.275 - Particulate matter control.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Particulate matter control. 52.275... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.275 Particulate matter control... particulate matter, and because there is no demonstration that their deletion would not interfere with the...

  8. Electrically heated particulate filter preparation methods and systems

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2012-01-31

    A control system that controls regeneration of a particulate filter is provided. The system generally includes a fuel control module that controls injection of fuel into exhaust that passes through the particulate filter. A regeneration module controls current to the particulate filter to initiate regeneration after the fuel has been injected into the exhaust.

  9. 40 CFR 52.2059 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... and secondary NAAQS for particulates. The schedule for this study is as follows: Schedule for...

  10. 40 CFR 52.2059 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... and secondary NAAQS for particulates. The schedule for this study is as follows: Schedule for...

  11. 40 CFR 52.2059 - Control strategy: Particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Particulate matter... Control strategy: Particulate matter. (a) Pennsylvania has committed to undertake a comprehensive program... and secondary NAAQS for particulates. The schedule for this study is as follows: Schedule for...

  12. Source apportionment of particulate matter in Denmark

    NASA Astrophysics Data System (ADS)

    Moenster, J.; Glasius, M.; Nielsen, O. J.; Bilde, M.; Jensen, F. P.

    2005-12-01

    Atmospheric particulate matter (PM) has received considerable attention over the last decade as an important component of air pollution, particularly due to its health effects on the exposed population. Typically the mass of particles with diameters smaller that 10 μm (PM10) has been used in large cohort studies to estimate health effects such as increase in hospitalization rate, asthma attacks and premature deaths. Particles smaller than 2.5 μm (PM2.5) and ultra fine particles have been used in various epidemiological studies and correlations between exposure to fine and ultra fine particles and health effects have been found. Limits of acceptable concentrations of PM10, PM2.5 and some carcinogenic species have been made, and it is important to find the origin of the particulate matter to prevent exceeds of these limits. This can be done by measuring particle mass, organic/inorganic fractions of particles, the chemical components and other relevant factors, and then use receptor modeling for source apportionment of the particulate matter. We have done measurements at street level and urban background in Copenhagen, Denmark, to determine the origin of different sizes of particulate matter and the toxic organic compounds connected to these particles. We also did measurements in a small village with less traffic and more residential wood combustion for a comparison between traffic and wood combustion generated pollution. Our results show a significant amount of particulate matter coming from non local sources and are dominated by long-range transported inorganic salts. The amount of these is highly depended on the wind direction and thus on the origin of the wind plume. The origin of the carcinogenic organic compound benzo(a)pyrene was found to be local combustion sources. To prevent events of high particulate matter concentration in Copenhagen, Denmark, a reduction of emission from the local traffic will only lead to a minor effect, since the majority of the

  13. Development of Particulates and Aerosols Research

    NASA Technical Reports Server (NTRS)

    DeWitt, Kenneth; Rivera, Monica

    2005-01-01

    During the past year several accomplishments were made for both the Particulate Matter Characterization and Measurement System, (PMCMS) and PAGEMS projects. The PAGEMS focus is to measure particulate emissions as a function of combustor parameters such as inlet temperature, inlet pressure and fuel air ratio. These measurements are used to evaluate combustor performance in hopes of correlating particulate emissions with engine conditions. These measurements have taken place at in-house NASA combustor facilities and off-site facilities. Ths work is unique because particulate measurements at high- pressure conditions are not commonly made. Some calibration of the PAGEMS instrumentation was done as well as minor modifications to the PAGEMS plumbing setup. These led to measurement improvements. The instrumentation and measurement process for PAGEMS was assessed and new instruments such as a thermodenuder, thermal mass flow meters and a cyclone separator were purchased to improve the PAGEMS instrumentation and measurement process. A worksheet was created to simulate varying inlet conditions to the DMA. This worksheet allows the user to assess the error in the measurements when certain conditions exist. Two technical papers were written with the PAGEMS team for the EXCAVATE field project. A paper was also reviewed for an in house publication. Also data was processed and analyzed for another field project (PAX) and will be part of a third PAGEMS paper. Accomplishments were also made with the PMCMS project. The calibration of the radial differential mobility analyzer, (RDMA) in the particle sizing system in the PMCMS was completed and provided satisfactory results. The voltages used for the RDMA depending on the particle of interest were corrected. The measurement capability of the PMCMS was increased by replacing the MetOne CPC with a TSI CPC. Lastly, assistance was provided to three college summer students with calibration of their particulate equipment and Monica Rivera

  14. Development of Particulates and Aerosols Research

    NASA Technical Reports Server (NTRS)

    DeWitt, Kenneth; Rivera, Monica

    2005-01-01

    During the past year several accomplishments were made for both the Particulate Matter Characterization and Measurement System, (PMCMS) and PAGEMS projects. The PAGEMS focus is to measure particulate emissions as a function of combustor parameters such as inlet temperature, inlet pressure and fuel air ratio. These measurements are used to evaluate combustor performance in hopes of correlating particulate emissions with engine conditions. These measurements have taken place at in-house NASA combustor facilities and off-site facilities. Ths work is unique because particulate measurements at high- pressure conditions are not commonly made. Some calibration of the PAGEMS instrumentation was done as well as minor modifications to the PAGEMS plumbing setup. These led to measurement improvements. The instrumentation and measurement process for PAGEMS was assessed and new instruments such as a thermodenuder, thermal mass flow meters and a cyclone separator were purchased to improve the PAGEMS instrumentation and measurement process. A worksheet was created to simulate varying inlet conditions to the DMA. This worksheet allows the user to assess the error in the measurements when certain conditions exist. Two technical papers were written with the PAGEMS team for the EXCAVATE field project. A paper was also reviewed for an in house publication. Also data was processed and analyzed for another field project (PAX) and will be part of a third PAGEMS paper. Accomplishments were also made with the PMCMS project. The calibration of the radial differential mobility analyzer, (RDMA) in the particle sizing system in the PMCMS was completed and provided satisfactory results. The voltages used for the RDMA depending on the particle of interest were corrected. The measurement capability of the PMCMS was increased by replacing the MetOne CPC with a TSI CPC. Lastly, assistance was provided to three college summer students with calibration of their particulate equipment and Monica Rivera

  15. Conception de couches minces tribologiques pour augmenter la resistance a l'erosion par impacts de particules

    NASA Astrophysics Data System (ADS)

    Hassani, Salim

    Solid particle erosion (SPE) is a serious problem in gas turbines, pumps, heat exchangers and piping systems in aircrafts and other applications. Sand and dust ingested by gas turbine engines may cause major damage to compressor gas path components, leading to severe performance degradation, excessive wear, increased maintenance and eventually premature failure of the engines. For the compressor section of aerospace gas turbine engines, in addition to the complex filtration systems used to screen the eroding particles, tribological coatings, such as TiN, Ti/TiN, CrN and TiAlN are used as protective layers of the base titanium alloy (Ti-6Al-4V) or stainless steels (17-4PH and 410) materials (substrates) against erosive wear. Such coatings can extend the service life of the components, but their performance still remains insufficient due to the complexity of failure mechanisms occurring upon SPE. Therefore, aerospace industry seeks to develop high performance coatings for the protection against erosion by solid particles. However, with many new materials used and tested for different applications and operation under different conditions, conducting experiments for each one of them is becoming increasingly difficult. Presently, coating selection criteria to prevent damage caused by erosion are based on trial and error experiments instead of prior design of coating's architecture and properties to maximize erosion resistance. The present work focuses on the use of advanced finite element (FE) methods to design erosion resistant (ER) coatings. It contributes a new methodology based on the analysis of transient stresses generated by a single impact event. Identification of coating architectures in which such stresses are minimized and crack propagation suppressed, allows one to predict and possibly minimize the erosion rate. Erosion mechanisms and governing erosion parameters are investigated to predict the coating behavior in simulated erosion conditions. The calculation variables include impact velocity (in the range of 50--300 m/s), particle size and the mechanical properties of both the target and the impacting particle. Specifically, we investigate the impact response of coatings fabricated by physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD). This includes single and multilayer TiN and nanocomposite nc-TiN/a-SiN1.3 and nc-TiCN/a-SiCN systems on titanium alloy and stainless steel substrates. In particular, we correlate the thickness and the coating macroscopic properties, such as hardness, Young's modulus, and toughness with the erosion. The calculations confirmed earlier findings that for a single layer coating, a combination of low modulus and a high thickness lead to local stress reduction and hence possible erosion resistance enhancement. The FE simulations have further shown that a tensile stress exceeding a critical stress sigmacrit = 3.95 GPa can be easily produced by a single particle impact. For each combination of particle velocity and size, a map of tensile stresses in the TiN coating, corresponding to the predicted erosion performance, was produced. The FE model has then been extended to multilayer coating systems containing superhard nanocomposite materials. These coatings configurations, when combined with tailored mechanical properties have shown to provide an improvement of the performance over comparable single layer configurations. The development of high performance erosion-resistant coatings also requires understanding of stress propagation upon particle impact. In the second part of this work, we apply a finite element methodology to enhance and optimize the resistance of protective coatings to erosion by solid particles with appropriate stress management. A controlled distribution of the initial residual stress in the coating was used to counteract impact stress, while a Young's modulus distribution was applied to optimize impact energy spreading throughout the coating system. Considering both tensile stress reduction and energy absorption, a multi-layer configuration with specific Young's modulus and residual stress distributions along the coating depth is suggested as an optimal coating architecture. In the third part of this work, we propose practical semi-empirical and numerical predictive methods to determine erosion resistance of tribological coatings. The study presents data obtained by FE calculations that can be compared with those obtained by classical theories developed for the erosion of materials. The simulation-based approach allows one to express the functional dependence of erosion on the coating properties, and to quantitatively predict the erosion rate. We determined a proportionality coefficient for a wide range of hard coatings. This coefficient was then used, in combination with the semi-empirical expression derived from FE simulations, to determine the erosion rate of different coatings. The existing erosion theories tend to emphasize hardness, H, and Young's modulus, E, as the main parameters defining erosion resistance. In this context, we specifically focus here on the role of the H/E and H3/E 2 ratios. We demonstrate that the latter characteristics allow one to rank coatings with respect to their erosion performance. Target values for these two ratios were determined for an optimal erosion resistance. We demonstrate that the FE design of the coating architecture, combined with the tailored mechanical properties of individual components of the coating systems, opens new opportunities as a predictive tool for high performance erosion coatings. The present thesis also includes a complementary experimental study of a new kind of ER coatings. We modify the surface profile of hard coatings such as diamond like carbon (DLC) and chrome silicon nitride CrSiN in attempt to correlate the surface characteristics to the functional performance. A specific surface texture (or pattern), designed to enhance erosion resistance, was obtained using a simple and cost effective method consisting of a masking operation, followed by conventional film fabrication techniques PVD or PECVD. Micro-patterned coatings (MPC) possessing specific 3D profiles were produced. In addition to a high potential for several tribological applications, MPC allowed to provide erosion resistance enhancement by a factor of 30 compared to the non-coated stainless steel and of 3--5 times compared to that of the same coating without micro pattern.

  16. Mesure par interférométrie laser du mouvement d'une particule proche d'une paroi

    NASA Astrophysics Data System (ADS)

    Assou, Y.; Joyeux, D.; Azouni, A.; Feuillebois, F.

    1991-02-01

    An experimental technique based on laser interferometry is used to obtain the displacement of a sphere towards a plane wall in a viscous fluid : it consists in inserting the sphere in an interferometric system, in such a way that the displacement of the sphere changes the state of interference. An important feature of the setup is that the shape, the roughness, and the positioning of the sphere in the optical path are relatively uncritical. The spheres used in the experiment are bearing balls, 4 and 5 × 10^{-3} m in diameter. The accuracy on the sphere displacement is of the order of 2 × 10^{-8} m. The interference signal is digitalized and stored in a microcomputer. The data are then processed to yield the friction coefficient f^T_zz of the sphere in its motion very close to the wall. The variation of f^T_zz with the non-dimensional gap \\varepsilon (ratio of the gap to the sphere radius) show three regions: (i) One in which a is small but at least 10 times larger than the non-dimensional rugosity (ratio of the scale of rugosity to the sphere radius) ; there is then a very good agreement with the result valid for a smooth sphere f^T_zz = 1/\\varepsilon from lubrication theory. (ii) When \\varepsilon decreases to the order of the non-dimensional rugosity, the friction coefficient is then smaller than 1/\\varepsilon. The technique thus opens a way to study the effects of rugosity in hydrodynamics. (iii) The technique allows to measure gaps of the order of 10^{-8} m and could thus be used in future studies of short ranges forces. On utilise une technique expérimentale basée sur l'interférométrie laser pour déterminer le déplacement d'une sphère s'approchant d'une paroi plane dans un fluide visqueux: la technique consiste à insérer la sphère dans un système interférométrique, de façon que son déplacement change l'état d'interférence détecté. Une particularité importante du montage utilisé est que la forme, l'état de surface, le positionnement, et l'alignement de la sphère dans le montage optique sont relativement peu critiques. Les sphères utilisées sont des billes de roulements à billes, de 4 et 5 × 10^{-3} m de diamètre. La précision sur le déplacement de la sphère est de l'ordre de 2 × 10^{-8} m. Le signal d'interférence est digitalisé et stocké dans un micro-ordinateur. Le traitement des données permet alors d'obtenir le coefficient de frottement f^T_zz de la sphère en mouvement tout près de la paroi. La variation de f^T_zz avec l'intervalle sans dimension \\varepsilon (rapport de l'intervalle entre la sphère et la paroi au rayon de la sphère) permet de distinguer trois régions: (i) Une région où \\varepsilon est petit mais au moins 10 fois plus grand que la rugosité non dimensionnelle (rapport de l'échelle de la rugosité au rayon de la sphère) ; le résultat expérimental est alors en très bon accord avec la formule f^T_zz = 1/\\varepsilon démontrée en théorie de la lubrification, formule valable pour une sphère lisse. (ii) Lorsque \\varepsilon décroît pour devenir de l'ordre de grandeur de la rugosité non dimensionnelle, le coefficient de frottement est alors inférieur à Il E. La technique ouvre ainsi une nouvelle voie à l'étude des effets de rugosité en hydrodynamique. (iii) La technique permet de mesurer des intervalles de l'ordre de 10^{-8} m et pourrait ainsi être utilisée dans l'étude des forces à courte portée.

  17. Structures of partition protein ParA with nonspecific DNA and ParB effector reveal molecular insights into principles governing Walker-box DNA segregation.

    PubMed

    Zhang, Hengshan; Schumacher, Maria A

    2017-03-01

    Walker-box partition systems are ubiquitous in nature and mediate the segregation of bacterial and archaeal DNA. Well-studied plasmid Walker-box partition modules require ParA, centromere-DNA, and a centromere-binding protein, ParB. In these systems, ParA-ATP binds nucleoid DNA and uses it as a substratum to deliver ParB-attached cargo DNA, and ParB drives ParA dynamics, allowing ParA progression along the nucleoid. How ParA-ATP binds nonspecific DNA and is regulated by ParB is unclear. Also under debate is whether ParA polymerizes on DNA to mediate segregation. Here we describe structures of key ParA segregation complexes. The ParA-β,γ-imidoadenosine 5'-triphosphate (AMPPNP)-DNA structure revealed no polymers. Instead, ParA-AMPPNP dimerization creates a multifaceted DNA-binding surface, allowing it to preferentially bind high-density DNA regions (HDRs). DNA-bound ParA-AMPPNP adopts a dimer conformation distinct from the ATP sandwich dimer, optimized for DNA association. Our ParA-AMPPNP-ParB structure reveals that ParB binds at the ParA dimer interface, stabilizing the ATPase-competent ATP sandwich dimer, ultimately driving ParA DNA dissociation. Thus, the data indicate how harnessing a conformationally adaptive dimer can drive large-scale cargo movement without the requirement for polymers and suggest a segregation mechanism by which ParA-ATP dimers equilibrate to HDRs shown to be localized near cell poles of dividing chromosomes, thus mediating equipartition of attached ParB-DNA substrates. © 2017 Zhang and Schumacher; Published by Cold Spring Harbor Laboratory Press.

  18. Recombination in the Human Pseudoautosomal Region PAR1

    PubMed Central

    Hinch, Anjali G.; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R.

    2014-01-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome. PMID:25033397

  19. Recombination in the human Pseudoautosomal region PAR1.

    PubMed

    Hinch, Anjali G; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R

    2014-07-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome.

  20. Measurements Of Scattered Light From Asbestos Particulate

    NASA Astrophysics Data System (ADS)

    Riis, P.; Ballik, E. A.

    1987-09-01

    Light-scattering techniques are potentially very important for the low-level detection and identification of particulate species such as asbestos in aerosol and liquid suspensions. Low-level detection is essential because asbestos is a known carcinogen, even at very-low exposure levels. At present, most asbestos particulate monitoring is used on optical microscopy. If detailed analysis is required, then electron microscopy is employed. Both of these methods are labour intensive. Furthermore, the optical microscopy method is not very reliable. Although the light-scattering techniques described here have general applicability, the emphasis is on asbestos measurements. Ordinary measurements of Mie scattering from asbestos suspensions can provide only limited information on asbestos content. owever, a more sophisticated technique can be employed which relies on the fact that asbestos particulate is fibrous rather than spherical in shape, and that the fibres align in a strong magnetic field (approximately 0.5 T). Particulate other than asbestos is generally non-fibrous in shape. Measurements have been carried out on liquid suspensions of asbestos contained in a small cell placed between the poles of a rotating magnet. The aligned fibres, which rotate about their centre of mass as they follow the field, are illuminated using a laser source. The Mie-scattering intensity is measured as a function of rotation angle, and the resulting data is then analysed with the aid of a microcomputer. Intensity maxima and minima provide reliable information on asbestos concentration, even in the presence of strong scattering from other particulate. In addition, the angular location of the intensity peaks provides information on the type of asbestos present. Each type has a characteristic alignment behaviour in a strong magnetic field. Using relatively-simple equipment, chrysotile asbestos (the most commonly-used type) has been detected at levels below 30 ng/l.

  1. Megestrol acetate NCD oral suspension -- Par Pharmaceutical: megestrol acetate nanocrystal dispersion oral suspension, PAR 100.2, PAR-100.2.

    PubMed

    2007-01-01

    Par Pharmaceutical has developed megestrol acetate (Megace ES) oral suspension for the treatment of anorexia, cachexia and a significant weight loss associated with AIDS. Par Pharmaceutical used Elan Corporation's NanoCrystal Dispersion (NCD) technology to develop an advanced, concentrated formulation of megestrol acetate with improved bioavailability, more rapid onset of action, more convenient dosing and a lower dosing regimen compared with the original marketed formulation of megestrol acetate oral suspension. Patients are administered a teaspoon (5mL) of the new NCD formulation once daily, compared with a daily 20mL dosage cup of the original formulation. The new megestrol acetate NCD formulation represents a line-extension of Par's megestrol acetate oral suspension (800mg/20mL, Megace O/S) that has been marketed for anorexia, cachexia and AIDS-related weight loss since July 2001. Par's megestrol acetate is the generic version of Bristol-Myers Squibb's Megace Oral Suspension. NanoCrystal Dispersion (NCD) is a trademark of Elan Corporation. Par Pharmaceutical will market megestol acetate NCD oral suspension under the Megace brand name. The company licensed the Megace name from Bristol-Myers Squib in August 2003. The US FDA approved megestrol acetate oral suspension (625 mg/mL) in July 2005 for the treatment of anorexia, cachexia or a significant, unexplained weight loss in patients with AIDS. The NDA for the product was accepted for review by the agency in September 2004, following its submission in June of that year.Par Pharmaceutical commenced the first of two phase III clinical trials of megestrol acetate oral suspension (PAR 100.2) in cancer-induced anorexia in the first quarter of 2006. However, this trial was discontinued in September 2006 because of slow patient enrolment. The company intends to discuss future development options in this indication with the FDA.New formulations or dosage forms of megestrol acetate concentrated suspension are also in

  2. Megestrol acetate NCD oral suspension--Par Pharmaceutical: megestrol acetate nanocrystal dispersion oral suspension, PAR 100.2, PAR-100.2.

    PubMed

    2007-01-01

    Par Pharmaceutical has developed megestrol acetate (Megace ES) oral suspension for the treatment of anorexia, cachexia and a significant weight loss associated with AIDS. Par Pharmaceutical used Elan Corporation's NanoCrystal Dispersion (NCD) technology to develop an advanced, concentrated formulation of megestrol acetate with improved bioavailability, more rapid onset of action, more convenient dosing and a lower dosing regimen compared with the original marketed formulation of megestrol acetate oral suspension. Patients are administered a teaspoon (5mL) of the new NCD formulation once daily, compared with a daily 20mL dosage cup of the original formulation. The new megestrol acetate NCD formulation represents a line-extension of Par's megestrol acetate oral suspension (800mg/20mL, Megace O/S) that has been marketed for anorexia, cachexia and AIDS-related weight loss since July 2001. Par's megestrol acetate is the generic version of Bristol-Myers Squibb's Megace Oral Suspension. NanoCrystal Dispersion (NCD) is a trademark of Elan Corporation. Par Pharmaceutical will market megestol acetate NCD oral suspension under the Megace brand name. The company licensed the Megace name from Bristol-Myers Squib in August 2003. The US FDA approved megestrol acetate oral suspension (625 mg/mL) in July 2005 for the treatment of anorexia, cachexia or a significant, unexplained weight loss in patients with AIDS. The NDA for the product was accepted for review by the agency in September 2004, following its submission in June of that year.Par Pharmaceutical commenced the first of two phase III clinical trials of megestrol acetate oral suspension (PAR 100.2) in cancer-induced anorexia in the first quarter of 2006. However, this trial was discontinued in September 2006 because of slow patient enrolment. The company intends to discuss future development options in this indication with the FDA.New formulations or dosage forms of megestrol acetate concentrated suspension are also in

  3. Détection de particules α à l'aide de charges électriques de surface

    NASA Astrophysics Data System (ADS)

    Charpak, G.; Cordurié, G.; Lewiner, J.; Morisseau, D.; Chabot, M.; Santiard, J.-C.

    La trajectoire d'une ou quelques particules α peut être visualisée en collectant sur un diélectrique les charges libérées dans un gaz le long de son trajet. La quantité de charges obtenue, sans multiplication, est faible et difficile à extraire du bruit de fond. Ce bruit de fond est dû, en particulier, aux charges ou à la polarisation résiduelles a la surface du diélectrique. Nous avons abaissé, de fçon sensible, ce niveau de charges résiduelles en les compensant avec les charges créées par une source de rayons α. La lecture des charges déposées par une seule particule est alors possible avec un dispositif de mesure électrométrique à tête tournante. The trajectory of one or a few α particles can be visualized by collecting on a dielectric the charges released in the gas by ionisation. The charge quantity obtained, without multiplication, is small and difficult to extract from the background noise. This background noise is, in particular, due to the residual charges or polarization near the surface of the dielectric. This residual surface charges have been significantly reduced by balancing them with charges created by a beam of α particles. Then, the reading of charges due to one particle can be performed with an electrometric measuring setup using a rotating head.

  4. Détection de particules α à l'aide de charges électriques de surface

    NASA Astrophysics Data System (ADS)

    Charpak, G.; Cordurié, G.; Lewiner, J.; Morisseau, D.; Chabot, M.; Santiard, J.-C.

    1993-12-01

    The trajectory of one or a few α particles can be visualized by collecting on a dielectric the charges released in the gas by ionisation. The charge quantity obtained, without multiplication, is small and difficult to extract from the background noise. This background noise is, in particular, due to the residual charges or polarization near the surface of the dielectric. This residual surface charges have been significantly reduced by balancing them with charges created by a beam of α particles. Then, the reading of charges due to one particle can be performed with an electrometric measuring setup using a rotating head. La trajectoire d'une ou quelques particules α peut être visualisée en collectant sur un diélectrique les charges libérées dans un gaz le long de son trajet. La quantité de charges obtenue, sans multiplication, est faible et difficile à extraire du bruit de fond. Ce bruit de fond est dû, en particulier, aux charges ou à la polarisation résiduelles à la surface du diélectrique. Nous avons abaissé, de façon sensible, ce niveau de charges résiduelles en les compensant avec les charges créées par une source de rayons α. La lecture des charges déposées par une seule particule est alors possible avec un dispositif de mesure électrométrique à tête tournante.

  5. Condensation and localization of the partitioning protein ParB on the bacterial chromosome.

    PubMed

    Broedersz, Chase P; Wang, Xindan; Meir, Yigal; Loparo, Joseph J; Rudner, David Z; Wingreen, Ned S

    2014-06-17

    The ParABS system mediates chromosome segregation and plasmid partitioning in many bacteria. As part of the partitioning mechanism, ParB proteins form a nucleoprotein complex at parS sites. The biophysical basis underlying ParB-DNA complex formation and localization remains elusive. Specifically, it is unclear whether ParB spreads in 1D along DNA or assembles into a 3D protein-DNA complex. We show that a combination of 1D spreading bonds and a single 3D bridging bond between ParB proteins constitutes a minimal model for a condensed ParB-DNA complex. This model implies a scaling behavior for ParB-mediated silencing of parS-flanking genes, which we confirm to be satisfied by experimental data from P1 plasmids. Furthermore, this model is consistent with experiments on the effects of DNA roadblocks on ParB localization. Finally, we show experimentally that a single parS site is necessary and sufficient for ParB-DNA complex formation in vivo. Together with our model, this suggests that ParB binding to parS triggers a conformational switch in ParB that overcomes a nucleation barrier. Conceptually, the combination of spreading and bridging bonds in our model provides a surface tension ensuring the condensation of the ParB-DNA complex, with analogies to liquid-like compartments such as nucleoli in eukaryotes.

  6. Condensation and localization of the partitioning protein ParB on the bacterial chromosome

    PubMed Central

    Broedersz, Chase P.; Wang, Xindan; Meir, Yigal; Loparo, Joseph J.; Rudner, David Z.; Wingreen, Ned S.

    2014-01-01

    The ParABS system mediates chromosome segregation and plasmid partitioning in many bacteria. As part of the partitioning mechanism, ParB proteins form a nucleoprotein complex at parS sites. The biophysical basis underlying ParB–DNA complex formation and localization remains elusive. Specifically, it is unclear whether ParB spreads in 1D along DNA or assembles into a 3D protein–DNA complex. We show that a combination of 1D spreading bonds and a single 3D bridging bond between ParB proteins constitutes a minimal model for a condensed ParB–DNA complex. This model implies a scaling behavior for ParB-mediated silencing of parS-flanking genes, which we confirm to be satisfied by experimental data from P1 plasmids. Furthermore, this model is consistent with experiments on the effects of DNA roadblocks on ParB localization. Finally, we show experimentally that a single parS site is necessary and sufficient for ParB–DNA complex formation in vivo. Together with our model, this suggests that ParB binding to parS triggers a conformational switch in ParB that overcomes a nucleation barrier. Conceptually, the combination of spreading and bridging bonds in our model provides a surface tension ensuring the condensation of the ParB–DNA complex, with analogies to liquid-like compartments such as nucleoli in eukaryotes. PMID:24927534

  7. Control of cleavage spindle orientation in Caenorhabditis elegans: The role of the genes par-2 and par-3

    SciTech Connect

    Cheng, N.N.; Kirby, C.M.; Kemphues, K.J.

    1995-02-01

    Polarized asymmetric divisions play important roles in the development of plants and animals. The first two embryonic cleavages of Caenorhabditis elegans provide an opportunity to study the mechanisms controlling polarized asymmetric divisions. The first cleavage is unequal, producing daughters with different sizes and fates. The daughter blastomeres divide with different orientations at the second cleavage; the anterior blastomere divides equally across the long axis of the egg, whereas the posterior blastomere divides unequally along the long axis. We report here the results of our analysis of the genes par-2 and par-3 with respect to their contribution to the polarity of these divisions. Strong loss-of-function mutations in both genes lead to an equal first cleavage and an altered second cleavage. Interestingly, the mutations exhibit striking gene-specific differences at the second cleavage. The par-2 mutations lead to transverse spindle orientations in both blastomeres, whereas par-3 mutations lead to longitudinal spindle orientations in both blastomeres. The spindle orientation defects correlate with defects in centrosome movements during both the first and the second cell cycle. Temperature shift experiments with par-2 (it5ts) indicate that the par-2(+) activity is not required after the two-cell stage. Analysis of double mutants shows that par-3 is epistatic to par-2. We propose a model wherein par-2(+) and par-3(+) act in concert during the first cell cycle to affect asymmetric modification of the cytoskeleton. This polar modification leads to different behaviors of centrosomes in the anterior and posterior and leads ultimately to blastomere-specific spindle orientations at the second cleavage. 44 refs., 5 figs., 5 tabs.

  8. Scleral Buckling for Rhegmatogenous Retinal Detachment Associated with Pars Planitis

    PubMed Central

    Ahn, Jae Kyoun

    2016-01-01

    Purpose. To evaluate the surgical outcome of scleral buckling (SB) in rhegmatogenous retinal detachment (RRD) patients associated with pars planitis. Methods. Retrospective review of RRD patients (32 eyes of pars planitis RRD and 180 eyes of primary RRD) who underwent SB. We compared primary and final anatomical success rates and visual outcomes between two groups. Results. Primary and final anatomical success were achieved in 25 (78.1%) and 31 (96.8%) eyes in the pars planitis RRD group and in 167 eyes (92.7%) and 176 eyes (97.7%) in primary RRD group, respectively. Both groups showed significant visual improvement (p < 0.001) and there were no significant differences in final visual acuity. Pars planitis RRD group was associated with higher rate of postoperative proliferative vitreoretinopathy (PVR) development (12.5% versus 2.8%, p = 0.031). Pars planitis and high myopia were significant preoperative risk factors and pseudophakia was borderline risk for primary anatomical failure after adjusting for various clinical factors. Conclusions. Pars planitis associated RRD showed inferior primary anatomical outcome after SB due to postoperative PVR development. However, final anatomical and visual outcomes were favorable. RRD cases associated with pars planitis, high myopia, and pseudophakia might benefit from different surgical approaches, such as combined vitrectomy and SB. PMID:27688907

  9. Particulate Concentration Levels in Chinatown, Oakland, California

    NASA Astrophysics Data System (ADS)

    Chen, B.; Yeung, A.; Yu, J. F.

    2007-12-01

    Chinatown is located near the center of the busy business district of downtown Oakland, California. It is one of the most inhabited and congested areas in the City of Oakland, averaging 4,000 vehicles and 3,000 pedestrians per hour at a key intersection in the center of the neighborhood. Particles produced by automobiles and construction can settle into the bronchi of lungs and induce asthma attacks, irritate cardiovascular tissue, and possibly lead to lung cancer and death. Particulate pollution is a serious problem that is estimated to cause between 20,000 and 50,000 deaths per year in the US alone. Hence, evaluation of the air quality of the Chinatown neighborhood is important, because it helps to address issues that are of great concern to residents of the area. The primary goal of our project was to measure particulate concentration levels at various intersections in Oakland's Chinatown to determine if the air quality met U.S. EPA standards, and to take note of any trends that may occur over a period of months. We were primarily concerned with particles that are 2.5 micrometers diameter and smaller, as smaller particles are easily inhaled and directly affect the respiratory system. We were interested in identifying any intersections that may have had significantly higher levels than other intersections. Using a map of Chinatown, we chose 12 intersections and made measurements at these points over the course of six months, beginning in February and ending in July of 2007. Particulate matter measurements were made using a FLUKE 893 Particle Counter. Measurements recorded on the first day of our study, February 4, 2007, which was the day of an annual street festival, yielded the highest values for particulate matter concentration in our dataset. This was followed by a significant drop in concentration the following week, and then a gradual increase of concentration as the months progressed. No one location yielded values significantly higher than any other, and

  10. The Pars Triangularis in Dyslexia and ADHD

    PubMed Central

    Kibby, Michelle Y.; Kroese, Judith M.; Krebbs, Hillery; Hill, Crystal E.; Hynd, George W.

    2009-01-01

    Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one of the purposes of this study was to examine the structure of the PT in dyslexia and ADHD. The other purposes included examining the PT in relation to overall expressive language ability and in relation to several specific linguistic functions given language functioning often is affected in both dyslexia and ADHD. Participants included 50 children: 10 with dyslexia, 15 with comorbid dyslexia/ADHD, 15 with ADHD, and 10 controls. Using a 2 (dyslexia or not) X 2 (ADHD or not) MANCOVA, findings revealed PT length and shape were comparable between those with and without dyslexia. However, children with ADHD had smaller right PT lengths than those without ADHD, and right anterior ascending ramus length was related to attention problems in the total sample. In terms of linguistic functioning, presence of an extra sulcus in the left PT was related to poor expressive language ability. In those with adequate expressive language functioning, left PT length was related to phonological awareness, phonological short-term memory and rapid automatic naming (RAN). Right PT length was related to RAN and semantic processing. Further work on PT morphology in relation to ADHD and linguistic functioning is warranted. PMID:19356794

  11. Exploring the direct impacts of particulate matter and surface ozone on global crop production

    NASA Astrophysics Data System (ADS)

    Schiferl, L. D.; Heald, C. L.

    2016-12-01

    The current era of rising food demand to feed an increasing population along with expansion of industrialization throughout the globe has been accompanied by deteriorating air quality and an enhancement in agricultural activity. Both air quality and the food supply are vitally important to sustaining human enterprise, and understanding the effects air quality may have on agricultural production is critical. Particulate matter (PM) in the atmosphere decreases the total photosynthetically available radiation (PAR) available to crops through the scattering and absorption of radiation while also increasing the diffuse fraction (DF) of this PAR. Since plants respond positively to a higher DF through the more even distribution of photons to all leaves, the net effect of PM on crop production depends on the magnitudes of these values and the response mechanisms of a specific crop. In contrast, atmospheric ozone always acts to decrease crop production through its phytotoxic properties. While the relationships between ozone and crop production have been readily studied, the effects of PM on crop production and their relative importance compared to ozone is much more uncertain. This study uses the GEOS-Chem chemical transport model linked to the RRTMG radiative transfer model and the DSSAT crop model to explore the impacts of PM and ozone on the globally distributed production of maize, rice, wheat and soybeans. First, we examine how air quality differentially affects total seasonal production by crop and region. Second, we investigate the dependence of simulated production on air quality over different timescales and under varying cloud conditions.

  12. Multi-scale photoacoustic remote sensing (PARS) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Haji Reza, Parsin; Bell, Kevan; Shi, W.; Zemp, Roger J.

    2016-03-01

    We introduce a novel multi-scale photoacoustic remote sensing (PARS) imaging system. Our system can provide optical resolution details for superficial structures as well as acoustic resolution for deep-tissue imaging down to 5 cm, in a non-contact setting. PARS system does not require any contact with the sample or ultrasound coupling medium. The optical resolution PARS (OR-OARS) system uses optically focused pulsed excitation with optical detection of photoacoustic signatures using a long-coherence interrogation beam co-focused and co-scanned with the excitation spot. In the OR-PARS initial pressures are sampled right at their subsurface origin where acoustic pressures are largest. The Acoustic resolution PARS (AR-PARS) picks up the surface oscillation of the tissue caused by generated photoacoustic signal using a modified version of Michelson interferometry. By taking advantage of 4-meters polarization maintaining single-mode fiber and a green fiber laser we have generated a multi-wavelength source using stimulated Raman scattering. Remote functional imaging using this multi-wavelength excitation source and PARS detection mechanism has been demonstrated. The oxygen saturation estimations are shown for both phantom and in vivo studies. Images of blood vessel structures for an In vivo chicken embryo model is demonstrated. The Phantom studies indicates ~3µm and ~300µm lateral resolution for OR-PARS and AR-PARS respectively. To the best of our knowledge this is the first dual modality non-contact optical and acoustic resolution system used for in vivo imaging.

  13. Contribution of mycosporine-like amino acids and colored dissolved and particulate matter to sea ice optical properties and ultraviolet attenuation

    PubMed Central

    Uusikivi, Jari; Vähätalo, Anssi V.; Granskog, Mats A.; Sommaruga, Ruben

    2010-01-01

    In the Baltic Sea ice, the spectral absorption coefficients for particulate matter (PM) were about two times higher at ultraviolet wavelengths than at photosynthetically available radiation (PAR) wavelengths. PM absorption spectra included significant absorption by mycosporine-like amino acids (MAAs) between 320 and 345 nm. In the surface ice layer, the concentration of MAAs (1.37 μg L−1) was similar to that of chlorophyll a, resulting in a MAAs-to-chlorophyll a ratio as high as 0.65. Ultraviolet radiation (UVR) intensity and the ratio of UVR to PAR had a strong relationship with MAAs concentration (R2 = 0.97, n = 3) in the ice. In the surface ice layer, PM and especially MAAs dominated the absorption (absorption coefficient at 325 nm: 0.73 m−1). In the columnar ice layers, colored dissolved organic matter was the most significant absorber in the UVR (< 380 nm) (absorption coefficient at 325 nm: 1.5 m−1). Our measurements and modeling of UVR and PAR in Baltic Sea ice show that organic matter, both particulate and dissolved, influences the optical properties of sea ice and strongly modifies the UVR exposure of biological communities in and under snow-free sea ice. PMID:20585592

  14. Predicted PAR1 inhibitors from multiple computational methods

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Liu, Jinfeng; Zhu, Tong; Zhang, Lujia; He, Xiao; Zhang, John Z. H.

    2016-08-01

    Multiple computational approaches are employed in order to find potentially strong binders of PAR1 from the two molecular databases: the Specs database containing more than 200,000 commercially available molecules and the traditional Chinese medicine (TCM) database. By combining the use of popular docking scoring functions together with detailed molecular dynamics simulation and protein-ligand free energy calculations, a total of fourteen molecules are found to be potentially strong binders of PAR1. The atomic details in protein-ligand interactions of these molecules with PAR1 are analyzed to help understand the binding mechanism which should be very useful in design of new drugs.

  15. Limnological database for Par Pond: 1959 to 1980

    SciTech Connect

    Tilly, L.J.

    1981-03-01

    A limnological database for Par Pond, a cooling reservoir for hot reactor effluent water at the Savannah River Plant, is described. The data are derived from a combination of research and monitoring efforts on Par Pond since 1959. The approximately 24,000-byte database provides water quality, primary productivity, and flow data from a number of different stations, depths, and times during the 22-year history of the Par Pond impoundment. The data have been organized to permit an interpretation of the effects of twenty years of cooling system operations on the structure and function of an aquatic ecosystem.

  16. Atmospheric particulate analysis using angular light scattering

    NASA Technical Reports Server (NTRS)

    Hansen, M. Z.

    1980-01-01

    Using the light scattering matrix elements measured by a polar nephelometer, a procedure for estimating the characteristics of atmospheric particulates was developed. A theoretical library data set of scattering matrices derived from Mie theory was tabulated for a range of values of the size parameter and refractive index typical of atmospheric particles. Integration over the size parameter yielded the scattering matrix elements for a variety of hypothesized particulate size distributions. A least squares curve fitting technique was used to find a best fit from the library data for the experimental measurements. This was used as a first guess for a nonlinear iterative inversion of the size distributions. A real index of 1.50 and an imaginary index of -0.005 are representative of the smoothed inversion results for the near ground level atmospheric aerosol in Tucson.

  17. Face crack reduction strategy for particulate filters

    DOEpatents

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

    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.

  18. NICKEL SPECIATION OF URBAN PARTICULATE MATTER

    SciTech Connect

    Kevin C. Galbreath; Charlene R. Crocker; Carolyn M. Nyberg; Frank E. Huggins; Gerald P. Huffman

    2003-10-01

    A four-step sequential Ni extraction method, summarized in Table AB-1, was evaluated for identifying and quantifying the Ni species occurring in urban total suspended particulate (TSP) matter and fine particulate matter (<10 {micro}m [PM{sub 10}] and <2.5 {micro}m [PM{sub 2.5}] in aerodynamic diameter). The extraction method was originally developed for quantifying soluble, sulfidic, elemental, and oxidic forms of Ni that may occur in industrial atmospheres. X-ray diffraction (XRD) and x-ray absorption fine structure (XAFS) spectroscopy were used to evaluate the Ni species selectivity of the extraction method. Uncertainties in the chemical speciation of Ni in urban PM{sub 10} and PM{sub 2.5} greatly affect inhalation health risk estimates, primarily because of the large variability in acute, chronic, and cancer-causing effects for different Ni compounds.

  19. Particulate contaminant relocation during shuttle ascent

    NASA Technical Reports Server (NTRS)

    Scialdone, J. J.

    1986-01-01

    The dislodgement, venting, and redeposition of particles on a surface in the shuttle bay by the vibroacoustic, gravitational, and aerodynamic forces present during shuttle ascent have been investigated. The particles of different sizes which are displaced, vented, and redistributed have been calculated; and an estimate of the increased number of particles on certain surfaces and the decrease on others has been indicated. The average sizes, velocities, and length of time for certain particles to leave the bay following initial shuttle doors opening and thermal tests have been calculated based on indirect data obtained during several shuttle flights. Suggestions for future measurements and observations to characterize the particulate environment and the techniques to limit the in-orbit particulate contamination of surfaces and environment have been offered.

  20. Sensor Technologies for Particulate Detection and Characterization

    NASA Technical Reports Server (NTRS)

    Greenberg, Paul S.

    2008-01-01

    Planned Lunar missions have resulted in renewed attention to problems attributable to fine particulates. While the difficulties experienced during the sequence of Apollo missions did not prove critical in all cases, the comparatively long duration of impending missions may present a different situation. This situation creates the need for a spectrum of particulate sensing technologies. From a fundamental perspective, an improved understanding of the properties of the dust fraction is required. Described here is laboratory-based reference instrumentation for the measurement of fundamental particle size distribution (PSD) functions from 2.5 nanometers to 20 micrometers. Concomitant efforts for separating samples into fractional size bins are also presented. A requirement also exists for developing mission compatible sensors. Examples include provisions for air quality monitoring in spacecraft and remote habitation modules. Required sensor attributes such as low mass, volume, and power consumption, autonomy of operation, and extended reliability cannot be accommodated by existing technologies.

  1. Glints from particulate media and wavy surfaces

    NASA Astrophysics Data System (ADS)

    Borovoi, Anatoli; Konoshonkin, Alexander; Kolokolova, Ludmilla

    2012-12-01

    Glints are bright light spots created by particulate media like cirrus clouds, glaciers, and wavy water surfaces. They are seen around the specular reflection angle. In this paper, the glints from such scattering/reflecting media are described in a unified manner through the probability density for facet tilts. Various kinds of these probability densities for wavy surfaces are defined and classified. The concept of the differential scattering cross section (DSCS) for rough surfaces instead of the conventional bidirectional reflectance distribution function (BRDF) is introduced for characterization of the glints. The simple equations connecting the DSCS and the probability densities for facet tilts are derived. It is shown that the glints from particulate media and wavy surface are very similar at small incidence angles and they are significantly different at slant incidence.

  2. Lidar measurements of airborne particulate matter

    NASA Astrophysics Data System (ADS)

    Li, Guangkun; Philbrick, C. Russell

    2003-03-01

    Raman lidar techniques have been used in remote sensing to measure the aerosol optical extinction in the lower atmosphere, as well as water vapor, temperature and ozone profiles. Knowledge of aerosol optical properties assumes special importance in the wake of studies strongly correlating airborne particulate matter with adverse health effects. Optical extinction depends upon the concentration, composition, and size distribution of the particulate matter. Optical extinction from lidar returns provide information on particle size and density. The influence of relative humidity upon the growth and size of aerosols, particularly the sulfate aerosols along the northeast US region, has been investigated using a Raman lidar during several field measurement campaigns. A particle size distribution model is being developed and verified based on the experimental results. Optical extinction measurements from lidar in the NARSTO-NE-OPS program in Philadelphia PA, during summer of 1999 and 2001, have been analyzed and compared with other measurements such as PM sampling and particle size measurements.

  3. Particulate models of photosynthesis. Annual progress report

    SciTech Connect

    Seely, G.R.

    1982-09-01

    A program was initiated to study the photochemical and photophysical properties of chlorophyll adsorbed together with various surfactants to particles of polyethylene swollen with low molecular weight diluents, with the eventual objective of establishing conditions for useful conversion of solar energy. The specific objectives of the program are (1) to prepare such particulate systems and characterize them, especially through analysis of their absorption and fluorescence spectra, (2) to investigate quantitatively the photochemistry of pigments in densely scattering media, and (3) to develop an analog of Photosystem II of green plants, in which a strong oxidant is generated in one phase and a mild reductant is accumulated in another. Results to date have shown that chlorophyll association and spectra are characteristic of the surfactant adsorbed with it, and that the particulate systems are capable of a vigorous and sometimes novel photochemistry.

  4. Characterization of iron in airborne particulate matter

    NASA Astrophysics Data System (ADS)

    Tavares, F. V. F.; Ardisson, J. D.; Rodrigues, P. C. H.; Brito, W.; Macedo, W. A. A.; Jacomino, V. M. F.

    2014-01-01

    In this work soil samples, iron ore and airborne atmospheric particulate matter (PM) in the Metropolitan Region of Belo Horizonte (MRBH), State of Minas Gerais, Brazil, are investigated with the aim of identifying if the sources of the particulate matter are of natural origin, such as, resuspension of particles from soil, or due to anthropogenic origins from mining and processing of iron ore. Samples were characterized by powder X-ray diffraction, X-ray fluorescence and 57Fe-Mössbauer spectroscopy. The results showed that soil samples studied are rich in quartz and have low contents of iron mainly iron oxide with low crystallinity. The samples of iron ore and PM have high concentration of iron, predominantly well crystallized hematite. 57Fe-Mössbauer spectroscopy confirmed the presence of similar iron oxides in samples of PM and in the samples of iron ore, indicating the anthropogenic origin in the material present in atmosphere of the study area.

  5. Apparatus for measuring surface particulate contamination

    DOEpatents

    Woodmansee, Donald E.

    2002-01-01

    An apparatus for measuring surface particulate contamination includes a tool for collecting a contamination sample from a target surface, a mask having an opening of known area formed therein for defining the target surface, and a flexible connector connecting the tool to the mask. The tool includes a body portion having a large diameter section defining a surface and a small diameter section extending from the large diameter section. A particulate collector is removably mounted on the surface of the large diameter section for collecting the contaminants. The tool further includes a spindle extending from the small diameter section and a spool slidingly mounted on the spindle. A spring is disposed between the small diameter section and the spool for biasing the spool away from the small diameter section. An indicator is provided on the spindle so as to be revealed when the spool is pressed downward to compress the spring.

  6. Innovations in high-temperature particulate filtration

    SciTech Connect

    Lippert, T.

    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.

  7. Shock Wave Structure in Particulate Composites

    NASA Astrophysics Data System (ADS)

    Rauls, Michael; Ravichandran, Guruswami

    2015-06-01

    Shock wave experiments are conducted on a particulate composite consisting of a polymethyl methacrylate (PMMA) matrix reinforced by glass beads. Such a composite with an impedance mismatch of 4.3 closely mimics heterogeneous solids of interest such as concrete and energetic materials. The composite samples are prepared using a compression molding process. The structure and particle velocity rise times of the shocks are examined using forward ballistic experiments. Reverse ballistic experiments are used to track how the interface density influences velocity overshoot above the steady state particle velocity. The effects of particle size (0.1 to 1 mm) and volume fraction of glass beads (30-40%) on the structure of the leading shock wave are investigated. It is observed that the rise time increases with increasing particle size and scales linearly for the range of particle sizes considered here. Results from numerical simulations using CTH are compared with experimental results to gain insights into wave propagation in heterogeneous particulate composites.

  8. Self-Cleaning Particulate Prefilter Media

    NASA Technical Reports Server (NTRS)

    Weber, Olivia; Lalwani, San-jiv; Sharma, Anjal

    2012-01-01

    A long-term space mission requires efficient air revitalization performance to sustain the crew. Prefilter and particulate air filter media are susceptible to rapid fouling that adversely affects their performance and can lead to catastrophic failure of the air revitalization system, which may result in mission failure. For a long-term voyage, it is impractical to carry replacement particulate prefilter and filter modules due to the usual limitations in size, volume, and weight. The only solution to this problem is to reagentlessly regenerate prefilter and filter media in place. A method was developed to modify the particulate prefilter media to allow them to regenerate reagentlessly, and in place, by the application of modest thermocycled transverse or reversed airflows. The innovation may allow NASA to close the breathing air loop more efficiently, thereby sustaining the vision for manned space exploration missions of the future. A novel, self-cleaning coatings technology was developed for air filter media surfaces that allows reagentless in-place regeneration of the surface. The technology grafts thermoresponsive and nonspecific adhesion minimizing polymer nanolayer brush coatings from the prefilter media. These polymer nanolayer brush architectures can be triggered to contract and expand to generate a "pushing-off" force by the simple application of modestly thermocycled (i.e. cycling from ambient cabin temperature to 40 C) air streams. The nonspecific adhesion-minimizing properties of the coatings do not allow the particulate foulants to adhere strongly to the filter media, and thermocycled air streams applied to the media allow easy detachment and in-place regeneration of the media with minimal impact in system downtime or astronaut involvement in overseeing the process.

  9. Aromatic Radicals-Acetylene Particulate Matter Chemistry

    DTIC Science & Technology

    2011-12-01

    atmosphere1. In addition to acute respiratory problems, long-term effects include lung cancer and cardiopulmonary diseases , as studied by Pope at al...problems such as ischemic heart disease , fatal arrhythmia, and congestive heart failure4,5. Strategies to reduce fine particulate matter (PM...acetylene reaction have been made by Fahr and Stein15, who deduced an Arrhenius expression in a 4 temperature range between 1000 and 1330 K in

  10. PARTICULATE MATTER NAAQS RISK AND EXPOSURE ...

    EPA Pesticide Factsheets

    The PM REA assesses human exposure and health risks for particulate matter. To provide a quantitative assessment of PM exposures and health risks as one of the key information inputs to the Administrator in order to make an informed decision regarding the PM NAAQS. A tiered risk/exposure assessment will be conducted as part of the PM NAAQS review and will be peer reviewed by the Clean Air Scientific Advisory Committee (CASAC) of EPA’s Science Advisory Board.

  11. Particulate debris osteolysis simulating malignant tumor.

    PubMed

    Brand, Richard A; Marsh, J Lawrence

    2004-01-01

    Osteolysis induced by particulate debris from total joint implants is typically confined to bone and benign in radiographic appearance even when extensive. However, they can extend well beyond bone in which case they can simulate malignancies owing either to mass effects and pressure on adjacent tissues or owing to the radiographic appearance. We report two cases which presented as possible malignancy, and review the literature on extensive osteolysis. Recognition of this possibility may aid in interpretation of the clinical presentation and imaging studies.

  12. Generator powered electrically heated diesel particulate filter

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J

    2014-03-18

    A control circuit for a vehicle powertrain includes a switch that selectivity interrupts current flow between a first terminal and a second terminal. A first power source provides power to the first terminal and a second power source provides power to the second terminal and to a heater of a heated diesel particulate filter (DPF). The switch is opened during a DPF regeneration cycle to prevent the first power source from being loaded by the heater while the heater is energized.

  13. Cometary particulate analyzer design definition study

    NASA Technical Reports Server (NTRS)

    Utterback, N. G.

    1981-01-01

    A concept for remotely determining the relative abundance of elements contained in cometary particulates collected by a spacecraft was conducted with very encouraging results. The technique utilizes a short high intensity burst of laser radiation to vaporize and ionize collected particulate material. Ions extracted from this laser-produced plasma are analyzed in a time of flight mass spectrometer to yield an atomic mass spectrum representative of the relative abundance of elements in the particulates. A prototype analyzer system was designed, constructed, and tested. Results show that: (1) energy-time focus performs as predicted in improving resolution; (2) power densities sufficient to produce usable ionization efficiencies can be obtained; (3) complex alloys such as stainless steel can be analyzed; and (4) a tiny, simple and reliable laser used in the demonstration easily meets spacecraft power and mass limitations. A mass resolution of 150 was experimentally demonstrated at mass 108, and an analytical extrapolation predicts a resolution sufficient to separate masses 250 and 251.

  14. Prediction of particulate contamination on aperture window

    NASA Technical Reports Server (NTRS)

    Lee, Aleck L.; Fong, Michael C.

    1994-01-01

    This paper presents an analysis to predict the effects of light scattering by surface particles on the sensor window of a missile during ascent flight. The particulate contaminant distribution on the window is calculated by tallying the number of particles in a set of size ranges. The particulate contamination at the end of the mission is predicted by adding the contributions from the events of ground and flight operations. The surface particle redistributions caused by vibroacoustically induced surface acceleration was found to contribute the most of the particulate surface contamination. The analytical surface obscuration calculation with a set of particle counts was compared to the results of image analyzer measurement. The analytical results, which were calculated with a given function of particle shape depending on the size, were more conservative than the measurement. A scattering calculation using a verified BSDF model showed that the scattering was less than 0.001 at 20 off the direction of the incident light in the mid IR wavelength when the surfaces were at Level 300 initially.

  15. Differential spectroscopic imaging of particulate explosives residue

    NASA Astrophysics Data System (ADS)

    Bernacki, Bruce E.; Hô, Nicolas

    2008-04-01

    We present experimental results showing transmission and reflection imaging of approximately 100 μg quantities of particulate explosives residue using a commercial uncooled microbolometer infrared camera and CO II laser differential wavelength illumination. Fine particulates may be generated during bomb-making activities and these particulates can tenaciously adhere to packing material, as well as to the clothing or skin of the bomb maker and could be detectable during transportation. A rapid screening method that detects this residue can serve as a first-line screening method in conjunction with more sensitive, but invasive, approaches. Explosives exhibit absorption features in the mid-infrared molecular fingerprint region that spans 3 to 15 μm, which can be probed with many high-brightness sources such as fixed wavelength and tunable quantum cascade lasers, CO II, CO, and OPO lasers. Commercial uncooled microbolometer cameras typically have detection sensitivity from 7.5 to 13 μm, spanning an absorption region for explosives detection with adequate signal-to-noise ratio. By illuminating a target on and off its absorption wavelengths, ratio images of suspected residue can be obtained without any sample preparation or cooperation and contact with the target. Our proof-of-principle experiment employed tunable CO II lasers, with a tuning range from 9.2 to 10.6 μm, overlapping minor absorption features of RDX and Tetryl.

  16. Spatial Reasoning and Understanding the Particulate Nature of Matter: A Middle School Perspective

    NASA Astrophysics Data System (ADS)

    Cole, Merryn L.

    This dissertation employed a mixed-methods approach to examine the relationship between spatial reasoning ability and understanding of chemistry content for both middle school students and their science teachers. Spatial reasoning has been linked to success in learning STEM subjects (Wai, Lubinski, & Benbow, 2009). Previous studies have shown a correlation between understanding of chemistry content and spatial reasoning ability (e.g., Pribyl & Bodner, 1987; Wu & Shah, 2003: Stieff, 2013), raising the importance of developing the spatial reasoning ability of both teachers and students. Few studies examine middle school students' or in-service middle school teachers' understanding of chemistry concepts or its relation to spatial reasoning ability. The first paper in this dissertation addresses the quantitative relationship between mental rotation, a type of spatial reasoning ability, and understanding a fundamental concept in chemistry, the particulate nature of matter. The data showed a significant, positive correlation between scores on the Purdue Spatial Visualization Test of Rotations (PSVT; Bodner & Guay, 1997) and the Particulate Nature of Matter Assessment (ParNoMA; Yezierski, 2003) for middle school students prior to and after chemistry instruction. A significant difference in spatial ability among students choosing different answer choices on ParNoMA questions was also found. The second paper examined the ways in which students of different spatial abilities talked about matter and chemicals differently. Students with higher spatial ability tended to provide more of an explanation, though not necessarily in an articulate matter. In contrast, lower spatial ability students tended to use any keywords that seemed relevant, but provided little or no explanation. The third paper examined the relationship between mental reasoning and understanding chemistry for middle school science teachers. Similar to their students, a significant, positive correlation between

  17. Chutes and Fissures in Greenland

    NASA Image and Video Library

    2015-05-12

    Scientists and crew with NASA’s Operation IceBridge, which makes annual aerial surveys of polar ice, are wrapping up their seventh campaign over the Arctic. In spring 2015, the team began using a different research aircraft—an adapted C-130 Hercules. They also added four new high-priority targets in the rapidly changing region of northeast Greenland. Many of the flights, however, were routine. And that’s exactly the point; making measurements over the same path each year provides continuity between NASA’s Ice, Cloud, and Land Elevation Satellite (ICESat) missions—the first of which ended in 2009 and the second of which is scheduled for launch in 2017. Repeat measurements show how a landscape changes over time. One area that has been surveyed repeatedly is northern Greenland’s Ryder Glacier. This photograph, taken during the IceBridge flight on May 6, 2015, shows a large moulin—dozens of meters across—atop this glacier. Moulins are holes in the ice sheet that drain melt water from the ice sheet’s surface to the bottom or out to the sea. Scientists are working to figure out what happens to melt water once it enters a moulin.

  18. LDSD Chute Beneath the Surface

    NASA Image and Video Library

    2014-08-08

    NASA Supersonic Disk Sail Parachute, one of the new technologies being developed as part of NASA Low-Density Supersonic Decelerator LDSD project, floats just below the surface of the Pacific Ocean on June 28, 2014.

  19. Positron Accumulator Ring (PAR) power supply

    SciTech Connect

    Fathizadeh, M.

    1995-08-01

    The Positron Accumulator Ring (PAR) consists of 8 dipole magnets connected in series. These magnets are energized via one 12-pulse dc power supply. The power supply consists of four phase controlled half-wave wye group converters. Each of the two half-wave converters are connected through an interphase transformer to obtain a full-wave converter with 120{degrees} conduction. The input voltage for these two half-wave converters are 180{degrees} apart. The two full-wave converters are connected in parallel through a third interphase transformer. This type of connection of the converters not only provides the required output current, it also improves the input power factor of the power supply. The output of the wye group converters is filtered through a passive L-R-C filter to reduce the ripple content of the output current. At low current values of the power supply the current ripple is high, thus a large filter is needed, which adds to the cost of the power supply, however at high output current levels, the current ripple is less severe. The large size of the filter can be reduced by adding an anti-parallel rectifier diode(D1) to the output of the power supply. A freewheeling diode(D2) is connected before the choke to circulate the current once the power supply is turned off. In order to measure the current in the magnet a high precision, low drift, zero flux current transductor is used. This transductor senses the magnet current which provides a feedback signal to control the gating of the converter`s thyristors. A true 14 bit Digital to Analog Converter (DAC) is programmed by the control computer for the required current value, providing a reference for the current regulator. Fast correction of the line transients is provided by a relatively fast voltage loop controlled by a high gain slow response current loop.

  20. PARS: Programs for Analysis and Resizing of Structures, user manual

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.; Prasad, B.; Tsach, U.

    1979-01-01

    PARS processors and their use, flutter analysis, sensitivity analysis for stresses, and resizing are presented. Design variable definition and interface with finite element model, static constraints and their derivatives, flutter derivatives, and optimization are discussed.