KSC-2010-5628

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers examine the seal from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

KSC-2010-5624

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the seal from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

KSC-2010-5640

NASA Image and Video Library

2010-11-11

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers move the ground umbilical carrier plate (GUCP) to a location where it can be examined. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Dimitri Gerondidakis

KSC-2010-5642

NASA Image and Video Library

2010-11-11

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers install a cap over the hole in space shuttle Discovery's external fuel tank where the ground umbilical carrier plate (GUCP) was removed. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Dimitri Gerondidakis

KSC-2010-5635

NASA Image and Video Library

2010-11-11

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to remove the ground umbilical carrier plate (GUCP) from space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Dimitri Gerondidakis

KSC-2010-5626

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers examine the seal from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

Testing of heat exchanger systems for reheating flue gases from wet scrubbing desulfurization plants

NASA Astrophysics Data System (ADS)

Than, K.

1982-09-01

Two heat exchanger systems: the cyclic process of GEA and, the plate heat exchanger of Kablitz/Thyssen, for reheating flue gases, which have been cooled to about 50 to 55 C due to wet scrubbing, to the required temperature at the outlet of the stack by extracting the sensible heat of the hot flue gases were tested. The problem of building materials and on keeping clean the heat exchanger surface are emphasized.

Magmatic gas scrubbing: Implications for volcano monitoring

USGS Publications Warehouse

Symonds, R.B.; Gerlach, T.M.; Reed, M.H.

2001-01-01

Despite the abundance of SO2(g) in magmatic gases, precursory increases in magmatic SO2(g) are not always observed prior to volcanic eruption, probably because many terrestrial volcanoes contain abundant groundwater or surface water that scrubs magmatic gases until a dry pathway to the atmosphere is established. To better understand scrubbing and its implications for volcano monitoring, we model thermochemically the reaction of magmatic gases with water. First, we inject a 915??C magmatic gas from Merapi volcano into 25??C air-saturated water (ASW) over a wide range of gas/water mass ratios from 0.0002 to 100 and at a total pressure of 0.1 MPa. Then we model closed-system cooling of the magmatic gas, magmatic gas-ASW mixing at 5.0 MPa, runs with varied temperature and composition of the ASW, a case with a wide range of magmatic-gas compositions, and a reaction of a magmatic gas-ASW mixture with rock. The modeling predicts gas and water compositions, and, in one case, alteration assemblages for a wide range of scrubbing conditions; these results can be compared directly with samples from degassing volcanoes. The modeling suggests that CO2(g) is the main species to monitor when scrubbing exists; another candidate is H2S(g), but it can be affected by reactions with aqueous ferrous iron. In contrast, scrubbing by water will prevent significant SO2(g) and most HCl(g) emissions until dry pathways are established, except for moderate HCl(g) degassing from pH 100 t/d (tons per day) of SO2(g) in addition to CO2(g) and H2S(g) should be taken as a criterion of magma intrusion. Finally, the modeling suggests that the interpretation of gas-ratio data requires a case-by-case evaluation since ratio changes can often be produced by several mechanisms; nevertheless, several gas ratios may provide useful indices for monitoring the drying out of gas pathways. Published by Elsevier Science B.V.

KSC-2010-5622

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers will focus their attention on the ground umbilical carrier plate (GUCP), which is on space shuttle Discovery's orange external fuel tank at the end of the access arm. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

KSC-2010-5741

NASA Image and Video Library

2010-11-30

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the ground umbilical carrier plate (GUCP) of space shuttle Discovery's external fuel tank has been repaired. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Dec. 17 at 8:51 p.m. EST. Until then, engineers will continue to analyze data from the GUCP and stringer crack repairs. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Cory Huston

KSC-2010-5742

NASA Image and Video Library

2010-11-30

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the ground umbilical carrier plate (GUCP) of space shuttle Discovery's external fuel tank has been repaired. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Dec. 17 at 8:51 p.m. EST. Until then, engineers will continue to analyze data from the GUCP and stringer crack repairs. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Cory Huston

KSC-2010-5623

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers are focusing their attention on the ground umbilical carrier plate (GUCP), which is on space shuttle Discovery's orange external fuel tank at the end of the access arm. A hydrogen gas leak at that location during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

Process for separating coal synthesized methane from unreacted intermediate and contaminant gases

DOEpatents

Barker, Ray E.; Scott, Charles D.; Ryon, Allen D.

1982-01-01

Gas produced from coal and containing CH.sub.4, CO, CO.sub.2, H.sub.2 and H.sub.2 S is contacted with CO.sub.2 scrub liquid to form (1) a liquid CO.sub.2 stream containing as solutes CH.sub.4, H.sub.2 S and minor portions of the CO and H.sub.2, and (2) a gas stream containing CO.sub.2 and major portions of the CO and H.sub.2, the CO and H.sub.2 in this stream being recycled to the means which produces gas from coal, and CO.sub.2 in the stream being recycled to the scrub liquid. The solute-bearing liquid CO.sub.2 stream is fractionated into (1) a liquid CO.sub.2 stream containing CH.sub.4 and H.sub.2 S, and (2) a H.sub.2 /CO gas stream which is recycled into contact with the scrub liquid. The last-mentioned liquid CO.sub.2 stream is fractionated into (1) a CH.sub.4 /CO.sub.2 gas stream the CO.sub.2 of which is recycled to the scrub liquid, and (2) a liquid CO.sub.2 stream containing H.sub.2 S, and CO.sub.2 of this stream is also recycled to the scrub liquid.

Process for separating coal synthesized methane from unreacted intermediate and contaminant gases. [Patent application

DOEpatents

Barker, R.E.; Scott, C.D.; Ryon, A.D.

1980-10-27

Gas produced from coal and containing CH/sub 4/, CO, CO/sub 2/, H/sub 2/ and H/sub 2/S is contacted with CO/sub 2/ scrub liquid to form (1) a liquid CO/sub 2/ stream containing as solutes CH/sub 4/, H/sub 2/S and minor portions of the CO and H/sub 2/, and (2) a gas stream containing CO/sub 2/ and major portions of the CO and H/sub 2/, the CO and H/sub 2/ in this stream being recycled to the means which produces gas from coal, and CO/sub 2/ in the stream being recycled to the scrub liquid. The solute-bearing liquid CO/sub 2/ stream is fractionated into (1) a liquid CO/sub 2/ stream containing CH/sub 4/ and H/sub 2/S, and (2) a H/sub 2//CO gas stream which is recycled into contact with the scrub liquid. The last-mentioned liquid CO/sub 2/ stream is fractionated into (1) a CH/sub 4//CO/sub 2/ gas stream the CO/sub 2/ of which is recycled to the scrub liquid, and (2) a liquid CO/sub 2/ stream containing H/sub 2/S, and CO/sub 2/ of this stream is also recycled to the scrub liquid.

Acid gas scrubbing by composite solvent-swollen membranes

DOEpatents

Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

1988-01-01

A composite immobilized liquid membrane suitable for acid gas scrubbing is disclosed. The membrane is a solvent-swollen polymer and a microporous polymeric support, the solvent being selected from a class of highly polar solvents containing at least one atom selected from nitrogen, oxygen, phosphorous and sulfur, and having a boiling point of at least 100.degree. C. and a solubility parameter of from about 7.5 to about 13.5 (cal/cm.sup.3 -atm).sup.1/2. Such solvents are homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. Also disclosed are methods of acid gas scrubbing of high- and low-Btu gas effluents with such solvent-swollen membranes.

Acid gas scrubbing by composite solvent-swollen membranes

DOEpatents

Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

1988-04-12

A composite immobilized liquid membrane suitable for acid gas scrubbing is disclosed. The membrane is a solvent-swollen polymer and a microporous polymeric support, the solvent being selected from a class of highly polar solvents containing at least one atom selected from nitrogen, oxygen, phosphorus and sulfur, and having a boiling point of at least 100 C and a solubility parameter of from about 7.5 to about 13.5 (cal/cm[sup 3]-atm)[sup 1/2]. Such solvents are homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. Also disclosed are methods of acid gas scrubbing of high- and low-Btu gas effluents with such solvent-swollen membranes. 3 figs.

Nebulization reflux concentrator

NASA Technical Reports Server (NTRS)

Collins, V. G.; Cofer, W. R., III

1986-01-01

A nebulization reflux concentrator for removing trace gas contaminants from a sample gas is described. Sample gas from a gas supply is drawn by a suction source into a vessel. The gas enters the vessel through an atomizing nozzle, thereby atomizing and entraining a scrubbing liquid solvent drawn through a siphon tube from a scrubbing liquid reservoir. The gas and entrained liquid rise through a concentrator and impinge upon a solvent phobic filter, whereby purified gas exits through the filter housing and contaminated liquid coalesces on the solvent phobic filter and falls into the reservoir.

PRECIPITATION CHEMISTRY OF MAGNESIUM SULFITE HYDRATES IN MAGNESIUM OXIDE SCRUBBING

EPA Science Inventory

The report gives results of laboratory studies defining the precipitation chemistry of MgSO3 hydrates. The results apply to the design of Mg-based scrubbing processes for SO2 removal from combustion flue gas. In Mg-based scrubbing processes, MgSO3 precipitates as either trihydrat...

KSC-2010-5611

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker begins to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5570

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5608

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5566

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5565

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5609

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker prepares to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5634

NASA Image and Video Library

2010-11-11

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers examine one of the ground umbilical carrier plate's (GUCP) quick disconnects. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

KSC-2010-5567

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5610

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5631

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove one of the ground umbilical carrier plate's (GUCP) quick disconnects. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Jack Pfaller

KSC-2010-5569

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5614

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect has been removed from the external fuel tank. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5568

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP) on space shuttle Discovery's external fuel tank. A hydrogen gas leak at that location during tanking for the STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

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

Microchannel Plates for the UVCS and SUMER Instruments on the SOHO Satellite

NASA Technical Reports Server (NTRS)

Siegmund, O. H. W.; Gummin, M. A.; Sasseen, T.; Jelinsky, P.; Gaines, G. A.; Hull, J.; Stock, J. M.; Edgar, M.; Welsh, B.; Jelinsky, S.;

KSC-2010-5616

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers take photos of the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect, which has been removed from the external fuel tank. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5613

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers take photos of the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect, which has been removed from the external fuel tank. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5595

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5572

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5560

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5564

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5571

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5607

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- As the sun rises over Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect are under way. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5617

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers take photos of the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect, which has been removed from the external fuel tank. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5561

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5598

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5597

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5562

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5563

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5559

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the tip-top of the bright-orange external fuel tank is where workers will prepare to begin removing the quick disconnect from the ground umbilical carrier plate (GUCP). A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is targeted for no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

KSC-2010-5596

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the vent line is detached from the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5606

NASA Image and Video Library

2010-11-10

CAPE CANAVERAL, Fla. -- As the sun begins to rise over Launch Pad 39A at NASA's Kennedy Space Center in Florida, preparations to remove the ground umbilical carrier plate's (GUCP) 7-inch quick disconnect are under way. A hydrogen gas leak at that location on the external fuel tank during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Troy Cryder

Performance of low resistance microchannel plate stacks

NASA Technical Reports Server (NTRS)

Siegmund, O. H. W.; Stock, J.

1991-01-01

Results are presented from an evaluation of three sets of low resistance microchannel plate (MCP) stacks; the tests encompassed gain, pulse-height distribution, background rate, event rate capacity as a function of illuminated area, and performance changes due to high temperature bakeout and high flux UV scrub. The MCPs are found to heat up, requiring from minutes to hours to reach stabilization. The event rate is strongly dependent on the size of the area being illuminated, with larger areas experiencing a gain drop onset at lower rates than smaller areas.

Laboratory Testing of a Fluidized Bed Dry Scrubbing Process for Removal of Sulfur Dioxide and Phosphorous Pentoxide from an Inert Carrier Gas.

DTIC Science & Technology

1988-03-01

flue gas desulfurization . A number of lab-scale studies have been conducted in...data on dry scrubbing of P205 could not be located. However, there is a significant volume of data in the literature on flue gas desulfurization and, to...8217’ ’--- -’ -- ’ -; ’ -’-’ .’ .’’. -’-’ - .".’,-" . ;"> . .. -, " ’. < + i i ,.- F).V A 23 REFERENCE S 1. A. Skopp et al., Fluid Bed Studies of the Limestone Based Flue Gas

Direct energy recovery from primary and secondary sludges by supercritical water oxidation.

PubMed

Svanström, M; Modell, M; Tester, J

2004-01-01

Supercritical water oxidation (SCWO) oxidizes organic and biological materials virtually completely to benign products without the need for stack gas scrubbing. Heavy metals are recovered as stabilized solid, along with the sand and clay that is present in the feed. The technology has been under development for twenty years. The major obstacle to commercialization has been developing reactors that are not clogged by inorganic solid deposits. That problem has been solved by using tubular reactors with fluid velocities that are high enough to keep solids in suspension. Recently, system designs have been created that reduce the cost of processing sewage sludges below that of incineration. At 10 wt- % dry solids, sludge can be oxidized with virtually complete recovery of the sludge heating value as hot water or high-pressure steam. Liquid carbon dioxide of high purity can be recovered from the gaseous effluent and excess oxygen can be recovered for recycle. The net effect is to reduce the stack to a harmless vent with minimal flow rate of a clean gas. Complete simulations have been developed using physical property models that accurately simulate the thermodynamic properties of sub- and supercritical water in mixtures with O2, N2, CO2, and organics. Capital and operating cost estimates are given for sewage sludge treatment, which are less costly than incineration. The scenario of direct recovery of energy from sludges has inherent benefits compared to other gasification or liquefaction options.

Evaluation of a Zirconium Recycle Scrubber System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spencer, Barry B.; Bruffey, Stephanie H.

2017-04-01

A hot-cell demonstration of the zirconium recycle process is planned as part of the Materials Recovery and Waste Forms Development (MRWFD) campaign. The process treats Zircaloy® cladding recovered from used nuclear fuel with chlorine gas to recover the zirconium as volatile ZrCl4. This releases radioactive tritium trapped in the alloy, converting it to volatile tritium chloride (TCl). To meet regulatory requirements governing radioactive emissions from nuclear fuel treatment operations, the capture and retention of a portion of this TCl may be required prior to discharge of the off-gas stream to the environment. In addition to demonstrating tritium removal from amore » synthetic zirconium recycle off-gas stream, the recovery and quantification of tritium may refine estimates of the amount of tritium present in the Zircaloy cladding of used nuclear fuel. To support these objectives, a bubbler-type scrubber was fabricated to remove the TCl from the zirconium recycle off-gas stream. The scrubber was fabricated from glass and polymer components that are resistant to chlorine and hydrochloric acid solutions. Because of concerns that the scrubber efficiency is not quantitative, tests were performed using DCl as a stand-in to experimentally measure the scrubbing efficiency of this unit. Scrubbing efficiency was ~108% ± 3% with water as the scrubber solution. Variations were noted when 1 M NaOH scrub solution was used, values ranged from 64% to 130%. The reason for the variations is not known. It is recommended that the equipment be operated with water as the scrubbing solution. Scrubbing efficiency is estimated at 100%.« less

Method of removing oxides of sulfur and oxides of nitrogen from exhaust gases

DOEpatents

Walker, Richard J.

1986-01-01

A continuous method is presented for removing both oxides of sulfur and oxides of nitrogen from combustion or exhaust gases with the regeneration of the absorbent. Exhaust gas is cleaned of particulates and HCl by a water scrub prior to contact with a liquid absorbent that includes an aqueous solution of bisulfite and sulfite ions along with a metal chelate, such as, an iron or zinc aminopolycarboxylic acid. Following contact with the combustion gases the spent absorbent is subjected to electrodialysis to transfer bisulfite ions into a sulfuric acid solution while splitting water with hydroxide and hydrogen ion migration to equalize electrical charge. The electrodialysis stack includes alternate layers of anion selective and bipolar membranes. Oxides of nitrogen are removed from the liquid absorbent by air stripping at an elevated temperature and the regenerated liquid absorbent is returned to contact with exhaust gases for removal of sulfur oxides and nitrogen oxides.

KSC-2010-5590

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5592

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker begins to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5591

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5594

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5593

NASA Image and Video Library

2010-11-09

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers begin to remove the vent line attached to the ground umbilical carrier plate (GUCP) on the bright-orange external fuel tank. Next, the GUCP's 7-inch quick disconnect will be removed. A hydrogen gas leak at that location during tanking for space shuttle Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP will be examined to determine the cause of the hydrogen leak and then repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Discovery's next launch attempt is no earlier than Nov. 30 at 4:02 a.m. EST. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Frankie Martin

KSC-2010-5745

NASA Image and Video Library

2010-11-30

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the ground umbilical carrier plate (GUCP) and cracks on space shuttle Discovery's external fuel have been repaired. A hydrogen gas leak at the GUCP during tanking for Discovery's STS-133 mission to the International Space Station caused the launch attempt to be scrubbed Nov. 5. The GUCP is the overboard vent to the pad and the flame stack where the excess hydrogen is burned off. Also during initial loading operations, the foam cracked on two of the tank's 108 stringers, which are the composite aluminum ribs located vertically on the intertank area. Discovery's next launch attempt is no earlier than Dec. 17 at 8:51 p.m. EST. Until then, engineers will continue to analyze data from the GUCP and stringer crack repairs. For more information on STS-133, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Cory Huston

Radiation Tolerant Intelligent Memory Stack (RTIMS)

NASA Technical Reports Server (NTRS)

Ng, Tak-kwong; Herath, Jeffrey A.

2006-01-01

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

Application of Modern Coal Technologies to Military Facilities. Volume II. Evaluation of the Applicability and Cost of Current and Emerging Coal Technologies for the Utilization of Coal as a Primary Energy Source

DTIC Science & Technology

1968-05-01

flue gas . Is one. The more popular method Is wet limestone scrubbing. In the limestone Injection system, ground limestone Is mixed with the coal and...is removed. The remainder must be eliminated from the flue gas as SO2 by wet scrubbing. Reduced boiler efficiency, due to ash accumulation on the...use of the fluldlzed-bed boiler, rather than a conventional coal-fired boiler requiring a flue gas cleanup system, will result In an

Modular fuel-cell stack assembly

DOEpatents

Patel, Pinakin [Danbury, CT; Urko, Willam [West Granby, CT

2008-01-29

A modular multi-stack fuel-cell assembly in which the fuel-cell stacks are situated within a containment structure and in which a gas distributor is provided in the structure and distributes received fuel and oxidant gases to the stacks and receives exhausted fuel and oxidant gas from the stacks so as to realize a desired gas flow distribution and gas pressure differential through the stacks. The gas distributor is centrally and symmetrically arranged relative to the stacks so that it itself promotes realization of the desired gas flow distribution and pressure differential.

ECONOMICS OF DISPOSAL OF LIME/LIMESTONE SCRUBBING WASTES: UNTREATED AND CHEMICALLY TREATED WASTES

EPA Science Inventory

The report gives results of a detailed, comparative economic evaluation of four alternatives available to the utility industry for the disposal of wastes from flue gas desulfurization using limestone or lime slurry scrubbing. The alternatives are untreated sludge (pond or landfil...

40 CFR 464.31 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... discrete list of toxic organic pollutants for each process segment where it is regulated, as follows: (1... discrete wet scrubbing devices are employed in series in a single melting furnace exhaust gas stream. The ferrous melting furnace scrubber mass allowance shall be given to each discrete wet scrubbing device that...

System using electric furnace exhaust gas to preheat scrap for steelmaking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takai, K.; Iwasaki, K.

1987-09-08

A method is described for clean preheating of scrap contaminated with oil and organic matter, for steelmaking, using heat from exhaust gas flow from an electric furnace. It consists of: burning any combustibles present in the exhaust gas flow and simultanously separating out dust particles from the exhaust gas flow; heating a predetermined amount of the scrap by heat exchange with a predetermined portion of the exhaust gas flow; removing and collecting dust from the exhaust gas flow after preheating of scrap thereby; sensing the temperature of the exhaust flow; scrubbing the exhaust gas flow with an aqueous solution ofmore » a deodorant solvent flowing at a rate regulated to be in a predetermined relationship related to the exhaust gas temperature sensed prior to scrubbing, thereby generating saturated vapor and reducing the temperature of the exhaust gas flow by a predetermined amount; and electrostatically precipitating out oil mist attached to saturated water vapor and liquid droplets in the exhaust gas flow.« less

Scrubbing masks magmatic degassing during repose at Cascade-Range and Aleutian-Arc volcanoes

USGS Publications Warehouse

Symonds, Robert B.; Janik, C.J.; Evans, William C.; Ritchie, B.E.; Counce, Dale; Poreda, R.J.; Iven, Mark

2003-01-01

Between 1992 and 1998, we sampled gas discharges from ≤173°C fumaroles and springs at 12 quiescent but potentially restless volcanoes in the Cascade Range and Aleutian Arc (CRAA) including Mount Shasta, Mount Hood, Mount St. Helens, Mount Rainier, Mount Baker, Augustine Volcano, Mount Griggs, Trident, Mount Mageik, Aniakchak Crater, Akutan, and Makushin. For each site, we collected and analyzed samples to characterize the chemical (H2O, CO2, H2S, N2, CH4, H2, HCl, HF, NH3, Ar, O2, He) and isotopic (δ13C of CO2, 3He/4He, 40Ar/36Ar, δ34S, δ13C of CH4, δ15N, and δD and δ18O of water) compositions of the gas discharges, and to create baseline data for comparison during future unrest. The chemical and isotopic data show that these gases contain a magmatic component that is heavily modified from scrubbing by deep hydrothermal (150° - 350°C) water (primary scrubbing) and shallow meteoric water (secondary scrubbing). The impact of scrubbing is most pronounced in gas discharges from bubbling springs; gases from boiling-point fumaroles and superheated vents show progressively less impact from scrubbing. The most effective strategies for detecting gas precursors to future CRAA eruptions are to measure periodically the emission rates of CO2 and SO2, which have low and high respective solubilities in water, and to monitor continuously CO2 concentrations in soils around volcanic vents. Timely resampling of fumaroles can augment the geochemical surveillance program by watching for chemical changes associated with drying of fumarolic pathways (all CRAA sites), increases in gas geothermometry temperatures (Mount Mageik, Trident, Mount Baker, Mount Shasta), changes in δ13C of CO2 affiliated with magma movement (all CRAA site), and increases in 3He/4He coupled with intrusion of new magma (Mount Rainier, Augustine Volcano, Makushin, Mount Shasta). Repose magmatic degassing may discharge substantial amounts of S and Cl into the edifices of Mount Baker and several other CRAA volcanoes that is trapped by primary and secondary scrubbing. The consequent acidic fluids produce ongoing alteration in the 0.2- to 3-km-deep hydrothermal systems and in fields of boiling-point fumaroles near the surface. Such alteration may influence edifice stability and contribute to the formation of more-hazardous cohesive debris flows. In particular, we recommend further investigation of the volume, extent, and hazards of hydrothermal alteration at Mount Baker. Other potential hazards associated with the CRAA volcano hydrothermal systems include hydrothermal eruptions and, for deeper systems intruded by magma, deep-seated edifice collapse.

Cooler and particulate separator for an off-gas stack

DOEpatents

Wright, George T.

1992-01-01

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

Mercury sorbent delivery system for flue gas

DOEpatents

Klunder,; Edgar, B [Bethel Park, PA

2009-02-24

The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

Simultaneous removal of nitrogen oxide/nitrogen dioxide/sulfur dioxide from gas streams by combined plasma scrubbing technology.

PubMed

Chang, Moo Been; Lee, How Ming; Wu, Feeling; Lai, Chi Ren

2004-08-01

Oxides of nitrogen (NOx) [nitrogen oxide (NO) + nitrogen dioxide (NO2)] and sulfur dioxide (SO2) are removed individually in traditional air pollution control technologies. This study proposes a combined plasma scrubbing (CPS) system for simultaneous removal of SO2 and NOx. CPS consists of a dielectric barrier discharge (DBD) and wet scrubbing in series. DBD is used to generate nonthermal plasmas for converting NO to NO2. The water-soluble NO2 then can be removed by wet scrubbing accompanied with SO2 removal. In this work, CPS was tested with simulated exhausts in the laboratory and with diesel-generator exhausts in the field. Experimental results indicate that DBD is very efficient in converting NO to NO2. More than 90% removal of NO, NOx, and SO2 can be simultaneously achieved with CPS. Both sodium sulfide (Na2S) and sodium sulfite (Na2SO3) scrubbing solutions are good for NO2 and SO2 absorption. Energy efficiencies for NOx and SO2 removal are 17 and 18 g/kWh, respectively. The technical feasibility of CPS for simultaneous removal of NO, NO2, and SO2 from gas streams is successfully demonstrated in this study. However, production of carbon monoxide as a side-product (approximately 100 ppm) is found and should be considered.

Cocurrent scrubber evaluation TVA's Colbert Lime--Limestone Wet-Scrubbing Pilot Plant. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robards, R.F.; Moore, N.D.; Kelso, T.M.

1979-01-01

The Tennessee Valley Authority (TVA) is actively engaged in a pilot plant program to develop and/or evaluate wet-scrubbing processes for removing sulfur dioxide (SO/sub 2/) from boiler flue gas. The physical size and general arrangement of flue gas scrubbing systems have a major impact on capital investment and operating cost, as do potential operating and maintenance advantages inherent to some systems. The equipment configuration for a cocurrent scrubber reflects some of these advantages. EPRI funded TVA to perform preliminary screening tests of TVA's 1 MW pilot plant (Colbert Steam Plant) to develop operating data on the cocurrent design for usemore » in designing and operating a 10 MW prototype cocurrent scrubber at TVA's Shawnee Scrubber Test Facility. Results of the Colbert tests showed excellent sulfur dioxide removal efficiencies, generally greater than 85%, low pressure drop, and high particulate removal efficiencies. This report covers these screening tests.« less

Cooler and particulate separator for an off-gas stack

DOEpatents

Wright, G.T.

1991-04-08

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

Absorber modeling for NGCC carbon capture with aqueous piperazine.

PubMed

Zhang, Yue; Freeman, Brice; Hao, Pingjiao; Rochelle, Gary T

2016-10-20

A hybrid system combining amine scrubbing with membrane technology for carbon capture from natural gas combined cycle (NGCC) power plants is proposed in this paper. In this process, the CO 2 in the flue gas can be enriched from 4% to 18% by the membrane, and the amine scrubbing system will have lower capture costs. Aqueous piperazine (PZ) is chosen as the solvent. Different direct contact cooler (DCC) options, multiple absorber operating conditions, optimal intercooling designs, and different cooling options have been evaluated across a wide range of inlet CO 2 . Amine scrubbing without DCC is a superior design for NGCC carbon capture. Pump-around cooling at the bottom of the absorber can effectively manage the temperature of the hot flue gas, and still be effective for CO 2 absorption. The absorber gas inlet must be designed to avoid excessive localized temperature and solvent evaporation. When the inlet CO 2 increases from 4% to 18%, total absorber CAPEX decreases by 60%; another 10% of the total absorber CAPEX can be saved by eliminating the DCC. In-and-out intercooling works well for high CO 2 , while pump-around intercooling is more effective for low CO 2 . Dry cooling requires more packing and energy but appears to be technically and economically feasible if cooling water availability is limited.

Wet scrubbing of biomass producer gas tars using vegetable oil

NASA Astrophysics Data System (ADS)

Bhoi, Prakashbhai Ramabhai

The overall aims of this research study were to generate novel design data and to develop an equilibrium stage-based thermodynamic model of a vegetable oil based wet scrubbing system for the removal of model tar compounds (benzene, toluene and ethylbenzene) found in biomass producer gas. The specific objectives were to design, fabricate and evaluate a vegetable oil based wet scrubbing system and to optimize the design and operating variables; i.e., packed bed height, vegetable oil type, solvent temperature, and solvent flow rate. The experimental wet packed bed scrubbing system includes a liquid distributor specifically designed to distribute a high viscous vegetable oil uniformly and a mixing section, which was designed to generate a desired concentration of tar compounds in a simulated air stream. A method and calibration protocol of gas chromatography/mass spectroscopy was developed to quantify tar compounds. Experimental data were analyzed statistically using analysis of variance (ANOVA) procedure. Statistical analysis showed that both soybean and canola oils are potential solvents, providing comparable removal efficiency of tar compounds. The experimental height equivalent to a theoretical plate (HETP) was determined as 0.11 m for vegetable oil based scrubbing system. Packed bed height and solvent temperature had highly significant effect (p0.05) effect on the removal of model tar compounds. The packing specific constants, Ch and CP,0, for the Billet and Schultes pressure drop correlation were determined as 2.52 and 2.93, respectively. The equilibrium stage based thermodynamic model predicted the removal efficiency of model tar compounds in the range of 1-6%, 1-4% and 1-2% of experimental data for benzene, toluene and ethylbenzene, respectively, for the solvent temperature of 30° C. The NRTL-PR property model and UNIFAC for estimating binary interaction parameters are recommended for modeling absorption of tar compounds in vegetable oils. Bench scale experimental data from the wet scrubbing system would be useful in the design and operation of a pilot scale vegetable oil based system. The process model, validated using experimental data, would be a key design tool for the design and optimization of a pilot scale vegetable oil based system.

Probing Temperature Inside Planar SOFC Short Stack, Modules, and Stack Series

NASA Astrophysics Data System (ADS)

Yu, Rong; Guan, Wanbing; Zhou, Xiao-Dong

2017-02-01

Probing temperature inside a solid oxide fuel cell (SOFC) stack lies at the heart of the development of high-performance and stable SOFC systems. In this article, we report our recent work on the direct measurements of the temperature in three types of SOFC systems: a 5-cell short stack, a 30-cell stack module, and a stack series consisting of two 30-cell stack modules. The dependence of temperature on the gas flow rate and current density was studied under a current sweep or steady-state operation. During the current sweep, the temperature inside the 5-cell stack decreased with increasing current, while it increased significantly at the bottom and top of the 30-cell stack. During a steady-state operation, the temperature of the 5-cell stack was stable while it was increased in the 30-cell stack. In the stack series, the maximum temperature gradient reached 190°C when the gas was not preheated. If the gas was preheated and the temperature gradient was reduced to 23°C in the stack series with the presence of a preheating gas and segmented temperature control, this resulted in a low degradation rate.

Regenerable device for scrubbing breathable air of CO2 and moisture without special heat exchanger equipment

NASA Technical Reports Server (NTRS)

Tepper, E. H. (Inventor)

1977-01-01

The device concerns the circulation of cabin air through canisters which absorb and adsorb carbon dioxide, together with excess moisture, and return the scrubbed air to the cabin for recirculation. A coating on an inert substrate in granular form absorbs and adsorbs the impurities at standard temperatures and pressures, but desorbs such impurities at low pressures (vacuum) and standard temperatures. This fact is exploited by making the device in a stack of cells consisting of layers or cells which are isolated from one another flow-wise and are connected to separate manifolds and valving systems into two separate subsets. A first subset may be connected for the flow breathable air therethrough until the polyethyleneimine of its cells is saturated with CO2 and H2O. During the same period the second subset of cells is manifolded to a vacuum source.

System of treating flue gas

DOEpatents

Ziegler, D.L.

1975-12-01

A system is described for treating or cleaning incinerator flue gas containing acid gases and radioactive and fissionable contaminants. Flue gas and a quench solution are fed into a venturi and then tangentially into the lower portion of a receptacle for restricting volumetric content of the solution. The upper portion of the receptacle contains a scrub bed to further treat or clean the flue gas.

Electrochemical cell stack assembly

DOEpatents

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

2010-06-22

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

Chemical-oxidative scrubbing for the removal of hydrogen sulphide from raw biogas: potentials and economics.

PubMed

Miltner, M; Makaruk, A; Krischan, J; Harasek, M

2012-01-01

In the present work chemical-oxidative scrubbing as a novel method for the desulphurisation of raw biogas is presented with a special focus on the process potentials and economics. The selective absorption of hydrogen sulphide from gas streams containing high amounts of carbon dioxide using caustic solutions is not trivial but has been treated in literature. However, the application of this method to biogas desulphurisation has not been established so far. Based on rigorous experimental work, an industrial-scale pilot plant has been designed, erected and commissioned at a biogas plant with biogas upgrading and gas grid injection in Austria. Data collected from the 12-month monitored operation has been used to elaborate performance as well as economic parameters for the novel desulphurisation method. The proposed technology offers significant operational advantages regarding the degree of automation and the flexibility towards fluctuations in process boundary conditions. Furthermore, the economic assessment revealed the high competitiveness of the chemical-oxidative scrubbing process compared with other desulphurisation technologies with the named advantageous operational behaviour.

Multi-component removal in flue gas by aqua ammonia

DOEpatents

Yeh, James T [Bethel Park, PA; Pennline, Henry W [Bethel Park, PA

2007-08-14

A new method for the removal of environmental compounds from gaseous streams, in particular, flue gas streams. The new method involves first oxidizing some or all of the acid anhydrides contained in the gas stream such as sulfur dioxide (SO.sub.2) and nitric oxide (NO) and nitrous oxide (N.sub.2O) to sulfur trioxide (SO.sub.3) and nitrogen dioxide (NO.sub.2). The gas stream is subsequently treated with aqua ammonia or ammonium hydroxide which captures the compounds via chemical absorption through acid-base or neutralization reactions. The products of the reactions can be collected as slurries, dewatered, and dried for use as fertilizers, or once the slurries have been dewatered, used directly as fertilizers. The ammonium hydroxide can be regenerated and recycled for use via thermal decomposition of ammonium bicarbonate, one of the products formed. There are alternative embodiments which entail stoichiometric scrubbing of nitrogen oxides and sulfur oxides with subsequent separate scrubbing of carbon dioxide.

Performance evaluation of poly-urethane foam packed-bed chemical scrubber for the oxidative absorption of NH3 and H2S gases.

PubMed

Nisola, Grace M; Valdehuesa, Kris Niño G; Anonas, Alex V; Ramos, Kristine Rose M; Lee, Won-Keun; Chung, Wook-Jin

2018-01-02

The feasibility of open-pore polyurethane (PU) foam as packing material for wet chemical scrubber was tested for NH 3 and H 2 S removals. The foam is inexpensive, light-weight, highly porous (low pressure drop) and provides large surface area per unit volume, which are desirable properties for enhanced gas/liquid mass transfer. Conventional HCl/HOCl (for NH 3 ) and NaOH/NaOCl (for H 2 S) scrubbing solutions were used to absorb and oxidize the gases. Assessment of the wet chemical scrubbers reveals that pH and ORP levels are important to maintain the gas removal efficiencies >95%. A higher re-circulation rate of scrubbing solutions also proved to enhance the performance of the NH 3 and H 2 S columns. Accumulation of salts was confirmed by the gradual increase in total dissolved solids and conductivity values of scrubbing solutions. The critical elimination capacities at >95% gas removals were found to be 5.24 g NH 3 -N/m 3 -h and 17.2 g H 2 S-S/m 3 -h at an empty bed gas residence time of 23.6 s. Negligible pressure drops (< 4 mm H 2 O) after continuous operation demonstrate the suitability of PU as a practical packing material in wet chemical scrubbers for NH 3 and H 2 S removals from high-volume dilute emissions.

The Gonzaga desulfurization flue gas process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelleher, R.L.; O'Leary, T.J.; Shirk, I.A.

1984-01-01

The Gonzaga desulfurization flue gas process removes sulfur dioxide from a flue by cold water scrubbing. Sulfur dioxide is significantly more soluable in cold water (35/sup 0/F to 60/sup 0/F) than in warm water (100/sup 0/F). Sulfur dioxide reacts in water similarly as carbon dioxide reacts in water, in that both gasses are released from the water as the temperature of the water increases. The researchers at the Gonzaga University developed this process from the observations and techniques used in studying the acid and aldehyde concentrations in flue gasses with varying of fuel to air ratios. The apparatus was fixedmore » to a stationary engine and a gas/oil fired boiler. The flue gas was cooled to the dew point temperature of the air entering the combustion chamber on the pre-air heater. The system is described in two parts: the energies required for cooling in the scrubbing section and the energies required in the treatment section. The cold flue gas is utilized in cooling the scrubber section.« less

Improved aqueous scrubber for collection of soluble atmospheric trace gases

NASA Technical Reports Server (NTRS)

Cofer, W. R., III; Talbot, R. W.; Collins, V. G.

1985-01-01

A new concentration technique for the extraction and enrichment of water-soluble atmospheric trace gases has been developed. The gas scrubbing technique efficiently extracts soluble gases from a large volume flow rate of air sample into a small volume of refluxed trapping solution. The gas scrubber utilizes a small nebulizing nozzle that mixes the incoming air with an aqueous extracting solution to form an air/droplet mist. The mist provides excellent interfacial surface areas for mass transfer. The resulting mist sprays upward through the reaction chamber until it impinges upon a hydrophobic membrane that virtually blocks the passage of droplets but offers little resistance to the existing gas flow. Droplets containing the scrubbed gases coalesce on the membrane and drip back into the reservoir for further refluxing. After a suitable concentration period, the extracting solution containing the analyte can be withdrawn for analysis. The nebulization-reflex concentration technique is more efficient (maximum flow of gas through the minimum volume of extractant) than conventional bubbler/impinger gas extraction techniques and is offered as an alternative method.

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

NASA Technical Reports Server (NTRS)

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

1981-01-01

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

Modular fuel-cell stack assembly

DOEpatents

Patel, Pinakin

2010-07-13

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

Carbon dioxide scrubbing capabilities of two new nonpowered technologies.

PubMed

Norfleet, William; Horn, Wayne

2003-01-01

Current guidance for survivors aboard a disabled submarine (DISSUB) recommends the use of the "stir-and-fan" method of carbon dioxide (CO2) scrubbing in which the contents of canisters of lithium hydroxide (LiOH) are dispersed onto horizontal surfaces. This technique is objectionable because it releases large quantities of fine, caustic LiOH dust and it utilizes LiOH inefficiently. This report presents the results of laboratory studies of the CO2 scrubbing capabilities of two new products that might improve on "stir-and-fan": the Battelle Curtain (BC) and the Micropore Reactive Plastic Curtain (RPC). Experiments took place within a sealed hyperbaric chamber. CO2 was added to the chamber at a known mass flow that reproduced what might be encountered in a "worst-case" DISSUB scenario. Natural convection alone circulated gas within the chamber. The mass of BCs or RPCs necessary to limit CO2 to 3% for about 2 days was determined. The total scrubbing capacity (mass of CO2 scrubbed per unit mass of agent) of the BC was 0.756 +/- 0.012 (mean +/- SD), and the comparable value for the RPC was 0.808 +/- 0.007. Both products provided a scrubbing capacity that is close to the stoichiometric limit of the reaction (0.919). Neither product released sufficient caustic dust to prevent handling by a trained individual wearing no personal protective equipment.

Assessment of Mercury in Soils, Crops, Earthworms, and Water when Soil is Treated with Gypsum

USDA-ARS?s Scientific Manuscript database

Flue gas desulfurization (FGD) gypsum from fossil fuel combustion has many potential uses in agriculture, but there is concern about the potential environmental effects of its elevated mercury (Hg) concentration. The wet limestone scrubbing process that removes sulfur from flue gas (and produces gyp...

Multiscale observations of CO2, 13CO2, and pollutants at Four Corners for emission verification and attribution

PubMed Central

Lindenmaier, Rodica; Dubey, Manvendra K.; Henderson, Bradley G.; Butterfield, Zachary T.; Herman, Jay R.; Rahn, Thom; Lee, Sang-Hyun

2014-01-01

There is a pressing need to verify air pollutant and greenhouse gas emissions from anthropogenic fossil energy sources to enforce current and future regulations. We demonstrate the feasibility of using simultaneous remote sensing observations of column abundances of CO2, CO, and NO2 to inform and verify emission inventories. We report, to our knowledge, the first ever simultaneous column enhancements in CO2 (3–10 ppm) and NO2 (1–3 Dobson Units), and evidence of δ13CO2 depletion in an urban region with two large coal-fired power plants with distinct scrubbing technologies that have resulted in ∆NOx/∆CO2 emission ratios that differ by a factor of two. Ground-based total atmospheric column trace gas abundances change synchronously and correlate well with simultaneous in situ point measurements during plume interceptions. Emission ratios of ∆NOx/∆CO2 and ∆SO2/∆CO2 derived from in situ atmospheric observations agree with those reported by in-stack monitors. Forward simulations using in-stack emissions agree with remote column CO2 and NO2 plume observations after fine scale adjustments. Both observed and simulated column ∆NO2/∆CO2 ratios indicate that a large fraction (70–75%) of the region is polluted. We demonstrate that the column emission ratios of ∆NO2/∆CO2 can resolve changes from day-to-day variation in sources with distinct emission factors (clean and dirty power plants, urban, and fires). We apportion these sources by using NO2, SO2, and CO as signatures. Our high-frequency remote sensing observations of CO2 and coemitted pollutants offer promise for the verification of power plant emission factors and abatement technologies from ground and space. PMID:24843169

Theoretical Evidence for the Stronger Ability of Thymine to Disperse SWCNT than Cytosine and Adenine: self-stacking of DNA bases vs their cross-stacking with SWCNT

PubMed Central

Wang, Yixuan

2008-01-01

Self-stacking of four DNA bases, adenine (A), cytosine (C), guanine (G) and thymine (T), and their cross-stacking with (5,5) as well as (10,0) single walled carbon nanotubes (SWCNTs) were extensively investigated with a novel hybrid DFT method, MPWB1K/cc-pVDZ. The binding energies were further corrected with MP2/6-311++G(d,p) method in both gas phase and aqueous solution, where the solvent effects were included with conductor-like polarized continuum model (CPCM) model and UAHF radii. The strongest self-stacking of G and A takes displaced anti-parallel configuration, but un-displaced or “eclipsed” anti-parallel configuration is the most stable for C and T. In gas phase the self-stacking of nucleobases decreases in the sequence G>A>C>T, while because of quite different solvent effects their self-stacking in aqueous solution exhibits a distinct sequence A>G>T>C. For a given base, cross-stacking is stronger than self-stacking in both gas phase and aqueous solution. Binding energy for cross-stacking in gas phase varies as G>A>T>C for both (10,0) and (5,5) SWCNTs, and the binding of four nucleobases to (10,0) is slightly stronger than to (5,5) SWCNT by a range of 0.1–0.5 kcal/mol. The cross-stacking in aqueous solution varies differently from that gas phase: A>G>T>C for (10,0) SWCNT and G>A>T>C for (5,5) SWCNT. It is suggested that the ability of nucleobases to disperse SWCNT depends on relative strength (ΔΔEbinsol) of self-stacking and cross-stacking with SWCNT in aqueous solution. Of the four investigated nucleobases thymine (T) exhibits the highest (ΔΔEbinsol) which can well explain the experimental finding that T more efficiently functionalizes SWCNT than C and A. PMID:18946514

Compliance Testing of Grissom AFB Central Heating Plant Coal-Fired Boilers 3 and 5, Grissom AFB, Indiana

DTIC Science & Technology

1988-06-01

common breeching and can be routed to the wet-scrubber or to a bypass stack. The scrubber is a double-alkali flue - gas desulfurization system using soda...Illustrations Figure Title Page 1 View of Scrubber and Bypass Stacks 3 2 Scrubber Stacks 4 3 Bypass Stack 5 4 Flue Gas Flow Diagram 6 5 ORSAT Sampling...of gases and to provide a positive static pressure at flue gas exhaust discharge points. The ash system pneumatically removes ash from bottom-ash

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

PubMed

Elsner, Dorothea; Fomin, Anette

2002-01-01

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

The impact of stack geometry and mean pressure on cold end temperature of stack in thermoacoustic refrigeration systems

NASA Astrophysics Data System (ADS)

Wantha, Channarong

2018-02-01

This paper reports on the experimental and simulation studies of the influence of stack geometries and different mean pressures on the cold end temperature of the stack in the thermoacoustic refrigeration system. The stack geometry was tested, including spiral stack, circular pore stack and pin array stack. The results of this study show that the mean pressure of the gas in the system has a significant impact on the cold end temperature of the stack. The mean pressure of the gas in the system corresponds to thermal penetration depth, which results in a better cold end temperature of the stack. The results also show that the cold end temperature of the pin array stack decreases more than that of the spiral stack and circular pore stack geometry by approximately 63% and 70%, respectively. In addition, the thermal area and viscous area of the stack are analyzed to explain the results of such temperatures of thermoacoustic stacks.

SURVEY OF FLUE GAS DESULFURIZATION SYSTEMS: WILL COUNTY STATION, COMMONWEALTH EDISON CO

EPA Science Inventory

The report gives results of a second survey of the flue gas desulfurization (FGD) system on Unit 1 of Commonwealth Edison Co.'s Will County Station. The FGD system, started up in February 1972, uses a limestone slurry in two parallel scrubbing trains. Each train includes a ventur...

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, April--June 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

AQUATECH Systems, a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration.« less

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, October--December 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 2--3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler {number_sign}4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfur ormore » sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL Demonstration Program began September 10, 1991 and is approximately 22 months in duration.« less

Evaluation of gas cooling for pressurized phosphoric acid fuel cell stacks

NASA Technical Reports Server (NTRS)

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

1983-01-01

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

Cryogenic fractionator gas as stripping gas of fines slurry in a coking and gasification process

DOEpatents

DeGeorge, Charles W.

1981-01-01

In an integrated coking and gasification process wherein a stream of fluidized solids is passed from a fluidized bed coking zone to a second fluidized bed and wherein entrained solid fines are recovered by a scrubbing process and wherein the resulting solids-liquid slurry is stripped with a stripping gas to remove acidic gases, at least a portion of the stripping gas comprises a gas comprising hydrogen, nitrogen and methane separated from the coker products.

Aerodynamic improvement of the assembly through which gas conduits are taken into a smoke stack by simulating gas flow on a computer

NASA Astrophysics Data System (ADS)

Prokhorov, V. B.; Fomenko, M. V.; Grigor'ev, I. V.

2012-06-01

Results from computer simulation of gas flow motion for gas conduits taken on one and two sides into the gas-removal shaft of a smoke stack with a constant cross section carried out using the SolidWorks and FlowVision application software packages are presented.

2001 Industry Studies: Energy

DTIC Science & Technology

2001-01-01

standards can retrofit with flue - gas - desulfurization systems, use low sulfur coal, purchase emissions credits, or close. If a power plant’s emissions...a flue gas scrubbing device. IGCC technology is even more environmentally friendly. In an IGCC plant, coal is converted into a gaseous fuel, purified...and natural gas have rocketed this industry into the public’s spotlight and discussion. Secretary Abraham in a recent speech to the U.S. Chamber of

Fluidized Bed Boiler Assessment for Navy Applications

DTIC Science & Technology

1986-11-01

rather than removing it from the flue gas later with "scrubbing" devices. Intro- duction of limestone in the bed will reduce SO emissions; two...boiler in a satisfactory manner, the bed level, combustion temperature, and the flue gas composition and temperature should be continuously monitored...The flue gas composition should be c^-ɝely monitored for pollutants and combustion efficiency. EVOLUTION OF FBC BOILERS The performance of FBC

Design and scale-up of an oxidative scrubbing process for the selective removal of hydrogen sulfide from biogas.

PubMed

Krischan, J; Makaruk, A; Harasek, M

2012-05-15

Reliable and selective removal of hydrogen sulfide (H(2)S) is an essential part of the biogas upgrading procedure in order to obtain a marketable and competitive natural gas substitute for flexible utilization. A promising biogas desulfurization technology has to ensure high separation efficiency regardless of process conditions or H(2)S load without the use or production of toxic or ecologically harmful substances. Alkaline oxidative scrubbing is an interesting alternative to existing desulfurization technologies and is investigated in this work. In experiments on a stirred tank reactor and a continuous scrubbing column in laboratory-scale, H(2)S was absorbed from a gas stream containing large amounts of carbon dioxide (CO(2)) into an aqueous solution prepared from sodium hydroxide (NaOH), sodium bicarbonate (NaHCO(3)) and hydrogen peroxide (H(2)O(2)). The influence of pH, redox potential and solution aging on the absorption efficiency and the consumption of chemicals was investigated. Because of the irreversible oxidation reactions of dissolved H(2)S with H(2)O(2), high H(2)S removal efficiencies were achieved while the CO(2) absorption was kept low. At an existing biogas upgrading plant an industrial-scale pilot scrubber was constructed, which efficiently desulfurizes 180m(3)/h of raw biogas with an average removal efficiency of 97%, even at relatively high and strongly fluctuating H(2)S contents in the crude gas. Copyright © 2012 Elsevier B.V. All rights reserved.

40 CFR 98.173 - Calculating GHG emissions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b... stack gas volumetric flow rate (scfh). %H2O = Hourly moisture percentage in the stack gas. (iii) You... Tier 4 methodology in subpart C of this part, or through the same stack as any combustion unit or...

Flow Characteristics of a Multiple Nozzle Exhaust Gas Eductor System.

DTIC Science & Technology

1981-03-01

these exhaust gases are a temperatures significantly above those of conventionally powered ships. A few of the problems caused by these high temperatures ...systems designed for marine gas turbine applications must substantially cool exhaust gases , present an exterior stack surface temperature which will not...stack in. H 02 R - Gas constant for air, 53.34 ft-lbf/Ibm-R s - Entropy, Btu/Ibm-R S - Primary dimension of mixing stack T - Absolute temperature , R

Performance Testing of Tracer Gas and Tracer Aerosol Detectors for use in Radionuclide NESHAP Compliance Testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuehne, David Patrick; Lattin, Rebecca Renee

The Rad-NESHAP program, part of the Air Quality Compliance team of LANL’s Compliance Programs group (EPC-CP), and the Radiation Instrumentation & Calibration team, part of the Radiation Protection Services group (RP-SVS), frequently partner on issues relating to characterizing air flow streams. This memo documents the most recent example of this partnership, involving performance testing of sulfur hexafluoride detectors for use in stack gas mixing tests. Additionally, members of the Rad-NESHAP program performed a functional trending test on a pair of optical particle counters, comparing results from a non-calibrated instrument to a calibrated instrument. Prior to commissioning a new stack samplingmore » system, the ANSI Standard for stack sampling requires that the stack sample location must meet several criteria, including uniformity of tracer gas and aerosol mixing in the air stream. For these mix tests, tracer media (sulfur hexafluoride gas or liquid oil aerosol particles) are injected into the stack air stream and the resulting air concentrations are measured across the plane of the stack at the proposed sampling location. The coefficient of variation of these media concentrations must be under 20% when evaluated over the central 2/3 area of the stack or duct. The instruments which measure these air concentrations must be tested prior to the stack tests in order to ensure their linear response to varying air concentrations of either tracer gas or tracer aerosol. The instruments used in tracer gas and aerosol mix testing cannot be calibrated by the LANL Standards and Calibration Laboratory, so they would normally be sent off-site for factory calibration by the vendor. Operational requirements can prevent formal factory calibration of some instruments after they have been used in hazardous settings, e.g., within a radiological facility with potential airborne contamination. The performance tests described in this document are intended to demonstrate the reliable performance of the test instruments for the specific tests used in stack flow characterization.« less

Method for removal of nitrogen oxides from stationary combustion sources

NASA Technical Reports Server (NTRS)

Cooper, Charles D. (Inventor); Collins, Michelle M. (Inventor); Clausen, III, Christian A. (Inventor)

2004-01-01

A method for removing NO.sub.X from gas streams emanating from stationary combustion sources and manufacturing plants utilizes the injection of hydrogen peroxide into the gas stream for rapid gas-phase oxidation of NO to NO.sub.2 and water-soluble nitrogen acids HNO.sub.2 and HNO.sub.3. The nitrogen acids may be removed from the oxidized gas stream by wet scrubbing or by contact with a particulate alkaline material to form a nitrite/nitrate salt.

Hazardous Waste Minimization Initiation Decision Report. Volume 2. Appendixes.

DTIC Science & Technology

1988-06-01

remove particulate matter. The scrubber also neutralizes acidic vapors in the flue gas . Finally, the flue gas is neutralized in a packed scrubbing tower. A...of the calciner with the flue gases. The reclaimed grit, free of paint and fines, will be properly sized by adjusting the gas velocity in the...TECH OLOG be closely controlled in the range of 1000°-2000°F. The gas distribution grid in the reactor is a flat plate instead of a conical grid typical

Co-flow planar SOFC fuel cell stack

DOEpatents

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

2004-11-30

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

Electrically insulating and sealing frame

DOEpatents

Guthrie, Robin J.

1983-11-08

A combination gas seal and electrical insulator having a closed frame shape interconnects a fuel cell stack and a reactant gas plenum of a fuel cell generator. The frame can be of rectangular shape including at least one slidable spline connection in each side to permit expansion or contraction consistent with that of the walls of the gas plenum and fuel cell stack. The slidable spline connections in the frame sides minimizes lateral movement between the frame side members and sealing material interposed between the frame and the fuel cell stack or between the frame and the reactant gas plenum.

30 CFR 250.441 - What are the requirements for a surface BOP stack?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the BOP...

30 CFR 250.441 - What are the requirements for a surface BOP stack?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the BOP...

30 CFR 250.441 - What are the requirements for a surface BOP stack?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the BOP...

30 CFR 250.441 - What are the requirements for a surface BOP stack?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the BOP...

Porous coolant tube holder for fuel cell stack

DOEpatents

Guthrie, Robin J.

1981-01-01

A coolant tube holder for a stack of fuel cells is a gas porous sheet of fibrous material adapted to be sandwiched between a cell electrode and a nonporous, gas impervious flat plate which separates adjacent cells. The porous holder has channels in one surface with coolant tubes disposed therein for carrying coolant through the stack. The gas impervious plate is preferably bonded to the opposite surface of the holder, and the channel depth is the full thickness of the holder.

Air Emissions Inventory Guidance Document for Stationary Sources at Air Force Installations.

DTIC Science & Technology

1999-05-01

small stoker-fired boilers). sox Change to lower sulfur coal, Coal Cleaning, Flue Gas Desulfurization (e.g., wet scrubbing, spray drying, furnace...Multiclone Collector. SOx Flue Gas Desulfurization (e.g., wet , semi-dry, or dry scrubbers) NOx Low Excess Air, Burners out of Service, Biased Burner...both flue gas desulfurization spray dryer adsorber (FGD-SDA) and a fabric filter (FF). d Factors apply to boilers equipped with an electrostatic

Performance model of a recirculating stack nickel hydrogen cell

NASA Technical Reports Server (NTRS)

Zimmerman, Albert H.

1994-01-01

A theoretical model of the nickel hydrogen battery cell has been utilized to describe the chemical and physical changes during charge and overcharge in a recirculating stack nickel hydrogen cell. In particular, the movement of gas and electrolyte have been examined as a function of the amount of electrolyte put into the cell stack during cell activation, and as a function of flooding in regions of the gas screen in this cell design. Additionally, a two-dimensional variation on this model has been utilized to describe the effects of non-uniform loading in the nickel-electrode on the movement of gas and electrolyte within the recirculating stack nickel hydrogen cell. The type of nonuniform loading that has been examined here is that associated with higher than average loading near the surface of the sintered nickel electrode, a condition present to some degree in many nickel electrodes made by electrochemical impregnation methods. The effects of high surface loading were examined primarily under conditions of overcharge, since the movement of gas and electrolyte in the overcharging condition was typically where the greatest effects of non-uniform loading were found. The results indicate that significant changes in the capillary forces between cell components occur as the percentage of free volume in the stack filled by electrolyte becomes very high. These changes create large gradients in gas-filled space and oxygen concentrations near the boundary between the separator and the hydrogen electrode when the electrolyte fill is much greater than about 95 percent of the stack free volume. At lower electrolyte fill levels, these gaseous and electrolyte gradients become less extreme, and shift through the separator towards the nickel electrode. Similarly, flooding of areas in the gas screen cause higher concentrations of oxygen gas to approach the platinum/hydrogen electrode that is opposite the back side of the nickel electrode. These results illustrate the need for appropriate pore size distributions, and the maintenance of both convective electrolyte and gas flow paths through the stack, if the recirculating stack nickel hydrogen cell design is to work properly.

Kivihiilivoimalan Sivutuotteiden Maarakennuskaeytoen Elinkaariarviointi

DOT National Transportation Integrated Search

1998-01-01

The goal of this project was to assess the environmental impact of using fly ash and flue gas desulphurization (FGD) residues (produced by pulverized coal-fired power plants which employ semi dry scrubbing technology) in earthworks. The use of fly as...

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

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

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

Deployment Area Selection and Land Withdrawal/Acquisition. M-X/MPS (M-X/Multiple Protective Shelter) Environmental Technical Report. Power and Energy.

DTIC Science & Technology

1981-10-02

acceptable levels under the worst case condition of coal firing. The flue gas desulfurization system would be designed to reduce the sulfer dioxide content...approaches taken. There exists federal statutory authority to implement gas rationing under certain conditions. Thus, federal controls on oil production...such as air quality deterioration, water consumption, P wastewater generation, disposal of flue gas scrubbing sludge, and ash. Another alternative is

Compliance Testing of Grissom AFB Central Heating Plant Coal-Fired Boilers 3, 4, and 5, Grissom AFB, Indiana

DTIC Science & Technology

1989-06-01

to a common breeching and can be routed to the wet -scrubber or to a bypass stack. The scrubber is a double-alkali flue - gas desulfurization system...the ambient air Bw. = proportion by volume of water vapor in F, = a factor representing a ratio of the vol. the stack gas . ume of wet flue gases...Scrubbers and Bypass Stacks 4 3 Flue Gas Flow Diagram 5 4 ORSAT Sampling Train 8 5 ORSAT Apparatus 8 6 Particulate Sampling Train 9 Table 1 Emission

Compliance Testing of Grissom AFB, Central Heating Plant Coal-Fired Boilers 3, 4 and 5 Grissom AFB, Indiana.

DTIC Science & Technology

1991-03-01

common breeching and can be routed to the wet -scrubber or to a bypass stack. The scrubber is a double-alkali flue - gas desulfurization system using...air. B,,., = proportion by volume of water vapor in F, = a factor representing a ratio of the vol- the stack gas . ume of wet flue gases generated to...1 s- .- - Dtstr’, . iii i Illustrations Figure Title Page 1 View of Scrubbers and Bypass Stack 3 2 Flue Gas Flow Diagram 4 3 ORSAT Sampling Train

Comparative analysis between the alveolar recruitment maneuver and breath stacking technique in patients with acute lung injury

PubMed Central

Porto, Elias Ferreira; Tavolaro, Kelly Cristiani; Kumpel, Claudia; Oliveira, Fernanda Augusta; Sousa, Juciaria Ferreira; de Carvalho, Graciele Vieira; de Castro, Antonio Adolfo Mattos

2014-01-01

Objective To compare the effectiveness of the alveolar recruitment maneuver and the breath stacking technique with respect to lung mechanics and gas exchange in patients with acute lung injury. Methods Thirty patients were distributed into two groups: Group 1 - breath stacking; and Group 2 - alveolar recruitment maneuver. After undergoing conventional physical therapy, all patients received both treatments with an interval of 1 day between them. In the first group, the breath stacking technique was used initially, and subsequently, the alveolar recruitment maneuver was applied. Group 2 patients were initially subjected to alveolar recruitment, followed by the breath stacking technique. Measurements of lung compliance and airway resistance were evaluated before and after the use of both techniques. Gas analyses were collected before and after the techniques were used to evaluate oxygenation and gas exchange. Results Both groups had a significant increase in static compliance after breath stacking (p=0.021) and alveolar recruitment (p=0.03), but with no significant differences between the groups (p=0.95). The dynamic compliance did not increase for the breath stacking (p=0.22) and alveolar recruitment (p=0.074) groups, with no significant difference between the groups (p=0.11). The airway resistance did not decrease for either groups, i.e., breath stacking (p=0.91) and alveolar recruitment (p=0.82), with no significant difference between the groups (p=0.39). The partial pressure of oxygen increased significantly after breath stacking (p=0.013) and alveolar recruitment (p=0.04), but there was no significant difference between the groups (p=0.073). The alveolar-arterial O2 difference decreased for both groups after the breath stacking (p=0.025) and alveolar recruitment (p=0.03) interventions, and there was no significant difference between the groups (p=0.81). Conclusion Our data suggest that the breath stacking and alveolar recruitment techniques are effective in improving the lung mechanics and gas exchange in patients with acute lung injury. PMID:25028951

Comparative analysis between the alveolar recruitment maneuver and breath stacking technique in patients with acute lung injury.

PubMed

Porto, Elias Ferreira; Tavolaro, Kelly Cristiani; Kumpel, Claudia; Oliveira, Fernanda Augusta; Sousa, Juciaria Ferreira; Carvalho, Graciele Vieira de; Castro, Antonio Adolfo Mattos de

2014-01-01

To compare the effectiveness of the alveolar recruitment maneuver and the breath stacking technique with respect to lung mechanics and gas exchange in patients with acute lung injury. Thirty patients were distributed into two groups: Group 1 - breath stacking; and Group 2 - alveolar recruitment maneuver. After undergoing conventional physical therapy, all patients received both treatments with an interval of 1 day between them. In the first group, the breath stacking technique was used initially, and subsequently, the alveolar recruitment maneuver was applied. Group 2 patients were initially subjected to alveolar recruitment, followed by the breath stacking technique. Measurements of lung compliance and airway resistance were evaluated before and after the use of both techniques. Gas analyses were collected before and after the techniques were used to evaluate oxygenation and gas exchange. Both groups had a significant increase in static compliance after breath stacking (p=0.021) and alveolar recruitment (p=0.03), but with no significant differences between the groups (p=0.95). The dynamic compliance did not increase for the breath stacking (p=0.22) and alveolar recruitment (p=0.074) groups, with no significant difference between the groups (p=0.11). The airway resistance did not decrease for either groups, i.e., breath stacking (p=0.91) and alveolar recruitment (p=0.82), with no significant difference between the groups (p=0.39). The partial pressure of oxygen increased significantly after breath stacking (p=0.013) and alveolar recruitment (p=0.04), but there was no significant difference between the groups (p=0.073). The alveolar-arterial O2 difference decreased for both groups after the breath stacking (p=0.025) and alveolar recruitment (p=0.03) interventions, and there was no significant difference between the groups (p=0.81). Our data suggest that the breath stacking and alveolar recruitment techniques are effective in improving the lung mechanics and gas exchange in patients with acute lung injury.

Survey of flue gas desulfurization systems: Hawthorn Station, Kansas City Power and Light Co. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isaacs, G.A.; Zada, F.K.

1975-09-01

Results are given of a survey of the flue gas desulfurization (FGD) systems at Kansas City Power and Light Co.'s Hawthorn Power Station. The FGD systems on Hawthorn boilers 3 and 4 were designed to operate by injection of dry limestone in the boiler's furnace, followed by tail gas scrubbing. Because of tube plugging in boiler 4 the mode of operation of the FGD system on that boiler was modified: ground limestone is now introduced into the flue gas near the gas inlet to the scrubber tower. (GRA)

Evaporation of iodine-containing off-gas scrubber solution

DOEpatents

Partridge, J.A.; Bosuego, G.P.

1980-07-14

Mercuric nitrate-nitric acid scrub solutions containing radioiodine may be reduced in volume without excessive loss of volatile iodine. The use of concentrated nitric acid during an evaporation process oxidizes the mercury-iodide complex to a less volatile mercuric iodate precipitate.

REMOVAL OF SO2 FROM INDUSTRIAL WASTE GASES

EPA Science Inventory

The paper discusses technology for sulfur dioxide (SO2) pollution control by flue gas cleaning (called 'scrubbing') in the utility industry, a technology that has advanced significantly during the past 5 years. Federal Regulations are resulting in increasingly large-scale applica...

SO2 SCRUBBING TECHNOLOGIES: A REVIEW

EPA Science Inventory

The paper gives results of a review of commercially available flue gas desulfurization (FGD) technologies that have an established record of performance. Data on worldwide FGD applications reflect that wet FGD technologies have been used at most of the installations. Among the ...

Ambient pressure fuel cell system

DOEpatents

Wilson, Mahlon S.

2000-01-01

An ambient pressure fuel cell system is provided with a fuel cell stack formed from a plurality of fuel cells having membrane/electrode assemblies (MEAs) that are hydrated with liquid water and bipolar plates with anode and cathode sides for distributing hydrogen fuel gas and water to a first side of each one of the MEAs and air with reactant oxygen gas to a second side of each one of the MEAs. A pump supplies liquid water to the fuel cells. A recirculating system may be used to return unused hydrogen fuel gas to the stack. A near-ambient pressure blower blows air through the fuel cell stack in excess of reaction stoichiometric amounts to react with the hydrogen fuel gas.

The Direct FuelCell™ stack engineering

NASA Astrophysics Data System (ADS)

Doyon, J.; Farooque, M.; Maru, H.

FuelCell Energy (FCE) has developed power plants in the size range of 300 kW to 3 MW for distributed power generation. Field-testing of the sub-megawatt plants is underway. The FCE power plants are based on its Direct FuelCell™ (DFC) technology. This is so named because of its ability to generate electricity directly from a hydrocarbon fuel, such as natural gas, by reforming it inside the fuel cell stack itself. All FCE products use identical 8000 cm 2 cell design, approximately 350-400 cells per stack, external gas manifolds, and similar stack compression systems. The difference lies in the packaging of the stacks inside the stack module. The sub-megawatt system stack module contains a single horizontal stack whereas the MW-class stack module houses four identical vertical stacks. The commonality of the design, internal reforming features, and atmospheric operation simplify the system design, reduce cost, improve efficiency, increase reliability and maintainability. The product building-block stack design has been advanced through three full-size stack operations at company's headquarters in Danbury, CT. The initial proof-of-concept of the full-size stack design was verified in 1999, followed by a 1.5 year of endurance verification in 2000-2001, and currently a value-engineered stack version is in operation. This paper discusses the design features, important engineering solutions implemented, and test results of FCE's full-size DFC stacks.

Mercuric iodate precipitation from radioiodine-containing off-gas scrubber solution

DOEpatents

Partridge, Jerry A.; Bosuego, Gail P.

1982-01-01

Mercuric nitrate-nitric acid scrub solutions containing radioiodine may be reduced in volume without excessive loss of volatile iodine. The use of concentrated nitric acid during an evaporation process oxidizes the mercury-iodide complex to a less volatile mercuric iodate precipitate.

Stack Gas Scrubber Makes the Grade

ERIC Educational Resources Information Center

Chemical and Engineering News, 1975

1975-01-01

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

KSC-2009-3839

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – The afternoon sun casts shadows on space shuttle Endeavour's external fuel tank as workers remove the seal from the Ground Umbilical Carrier Plate, or GUCP, on the tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3840

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, work continues on removing the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

COMPUTERIZED SHAWNEE LIME/LIMESTONE SCRUBBING MODEL USERS MANUAL

EPA Science Inventory

The manual gives a general description of a computerized model for estimating design and cost of lime or limestone scrubber systems for flue gas desulfurization (FGD). It supplements PB80-123037 by extending the number of scrubber options which can be evaluated. It includes spray...

The S02 Concern in Developed Nations

ERIC Educational Resources Information Center

Environmental Science and Technology, 1976

1976-01-01

Delegates of a working group on air pollution problems of the Economic Commission for Europe discussed the status of advanced technologies for controlling man-made emissions of sulfur dioxide. Technologies discussed included: coal washing, oil desulfurization, flue gas desulfurization, scrubbing, residual oil desulfurization, fluidized bed…

A System Approach to Navy Medical Education and Training. Appendix 21. Orthopedic Technician.

DTIC Science & Technology

1974-08-31

33 1AMPUTATION SCRUB 34 IDISARTICULATION SCRUB 35 IARTHRODESIS SCRUB 36 ITRIPLE ARTHRODESIS SCRUB 37 IMENISECTOMY SCRUP 38 IOPEN REDUCTION OF...FRACTURES SCRUB 39 ISPINAL FUSION SCRUB 40 IHIP NAILING SCRUB 41 IINSERTION OF ORTHOPEDIC PINS, NAILS SCRUB 42 1EXTRACTION OF ORTHOPEDIC PINS SCRUB 43 IBONE...ITENDON TRANSFER SCRUB 48 IBUNIONECTOMY SCRUB 9 ISOUTHWICK PROCEDURE KNEE SCRUB 50 MAGUSON-STOCK REPAIR OF SHOULDER SCRUB TURN PAGE LEFT PAGE 04 ORTHO

Bio-methane from an-aerobic digestion using activated carbon adsorption.

PubMed

Farooq, Muhammad; Bell, Alexandra H; Almustapha, M N; Andresen, John M

2017-08-01

There is an increasing global demand for carbon-neutral bio-methane from an-aerobic digestion (AD) to be injected into national gas grids. Bio-gas, a methane -rich energy gas, is produced by microbial decomposition of organic matter through an-aerobic conditions where the presence of carbon dioxide and hydrogen sulphide affects its performance. Although the microbiological process in the AD can be tailored to enhance the bio-gas composition, physical treatment is needed to convert the bio-gas into bio-methane. Water washing is the most common method for upgrading bio-gas for bio-methane production, but its large use of water is challenging towards industrial scale-up. Hence, the present study focuses on scale-up comparison of water washing with activated-carbon adsorption using HYSYS and Aspen Process Economic Analyzer. The models show that for plants processing less than 500 m 3 /h water scrubbing was cost effective compared with activated carbon. However, against current fossil natural-gas cost of about 1 p/kWh in the UK both relied heavily on governmental subsidies to become economically feasible. For plants operating at 1000 m 3 /hr, the treatment costs were reduced to below 1.5 p/kWh for water scrubbing and 0.9 p/kWh for activated carbon where the main benefits of activated carbon were lower capital and operating costs and virtually no water losses. It is envisioned that this method can significantly aid the production of sustainable bio-methane. Copyright © 2017 Elsevier Ltd. All rights reserved.

Removal of NO from flue gas by aqueous chlorine-dioxide scrubbing solution in a lab-scale bubbling reactor.

PubMed

Deshwal, Bal Raj; Jin, Dong Seop; Lee, Si Hyun; Moon, Seung Hyun; Jung, Jong Hyeon; Lee, Hyung Keun

2008-02-11

The present study attempts to clean up nitric oxide from the simulated flue gas using aqueous chlorine-dioxide solution in the bubbling reactor. Chlorine-dioxide is generated by chloride-chlorate process. Experiments are carried out to examine the effect of various operating variables like input NO concentration, presence of SO(2), pH of the solution and NaCl feeding rate on the NO(x) removal efficiency at 45 degrees C. Complete oxidation of nitric oxide into nitrogen dioxide occurred on passing sufficient ClO(2) gas into the scrubbing solution. NO is finally converted into nitrate and ClO(2) is reduced into chloride ions. A plausible reaction mechanism concerning NO(x) removal by ClO(2) is suggested. DeNO(x) efficiency increased slightly with the increasing input NO concentration. The presence of SO(2) improved the NO(2) absorption but pH of solution showed marginal effect on NO(2) absorption. NO(x) removal mechanism changed when medium of solution changed from acidic to alkaline. A constant NO(x) removal efficiency of about 60% has been achieved in the wide pH range of 3-11 under optimized conditions.

Exhaust gas clean up process

DOEpatents

Walker, R.J.

1988-06-16

A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ is described. The method involves prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ gas or nitrogen sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt. 4 figs.

Sustainable uses of FGD gypsum in agricultural systems

USDA-ARS?s Scientific Manuscript database

Interest in using gypsum as a management tool to improve crop yields and soil/water quality has recently increased. Abundant supply and availability of flue gas desulfurization (FGD) gypsum, a by-product of scrubbing sulfur (S) from combustion gases at coal-fired power plants, in major agricultural...

Theoretical analysis of stack gas emission velocity measurement by optical scintillation

NASA Astrophysics Data System (ADS)

Yang, Yang; Dong, Feng-Zhong; Ni, Zhi-Bo; Pang, Tao; Zeng, Zong-Yong; Wu, Bian; Zhang, Zhi-Rong

2014-04-01

Theoretical analysis for an online measurement of the stack gas flow velocity based on the optical scintillation method with a structure of two parallel optical paths is performed. The causes of optical scintillation in a stack are first introduced. Then, the principle of flow velocity measurement and its mathematical expression based on cross correlation of the optical scintillation are presented. The field test results show that the flow velocity measured by the proposed technique in this article is consistent with the value tested by the Pitot tube. It verifies the effectiveness of this method. Finally, by use of the structure function of logarithmic light intensity fluctuations, the theoretical explanation of optical scintillation spectral characteristic in low frequency is given. The analysis of the optical scintillation spectrum provides the basis for the measurement of the stack gas flow velocity and particle concentration simultaneously.

Gas stream purifier

NASA Technical Reports Server (NTRS)

Adam, Steven J.

1994-01-01

A gas stream purifier has been developed that is capable of removing corrosive acid, base, solvent, organic, inorganic, and water vapors as well as particulates from an inert mixed gas stream using only solid scrubbing agents. This small, lightweight purifier has demonstrated the ability to remove contaminants from an inert gas stream with a greater than 99 percent removal efficiency. The Gas Stream Purifier has outstanding market and sales potential in manufacturing, laboratory and science industries, medical, automotive, or any commercial industry where pollution, contamination, or gas stream purification is a concern. The purifier was developed under NASA contract NAS9-18200 Schedule A for use in the international Space Station. A patent application for the Gas Stream Purifier is currently on file with the United States Patent and Trademark Office.

Correlation of plume opacity with particles and sulfates from boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lou, J.C.; Lee, M.; Chen, K.S.

1997-07-01

The effects of emission concentrations of particulate matters and sulfates on plume opacity are investigated by in situ measurements. The studies are conducted for three processes of two coal-fired plants and one oil-fired that are all equipped with electrostatic precipitators. Flue-gas sampling and analysis include the concentrations of particles and total water soluble sulfates, particle size distribution, and flue-gas composition; while in-stack and out-of-stack opacities are determined by a transmissometer and certified smoke inspectors, respectively. Experimental results show that plume opacity outside the stack linearly correlates well with the in-stack opacity. The mixing of hot flue gas with cold ambientmore » air would result in the condensation of hygroscopic sulfuric acid aerosols and an increase about 1.6% out of typical 15--25% measured opacity. An empirical equation similar to the Beer-Lambert-Bouger form is derived for predicting the plume opacity in terms of the stack diameter and the concentrations of particles and total water soluble sulfates. Good comparisons are achieved between predictions by the empirical equation and other available field data.« less

DEMONSTRATION OF WELLMAN-LORD/ALLIED CHEMICAL FGD TECHNOLOGY: DEMONSTRATION TEST SECOND YEAR RESULTS

EPA Science Inventory

The report gives results of an evaluation of the performance (over a 2-year period) of a full-scale flue gas desulfurization (FGD) unit to demonstrate the Wellman-Lord/Allied Chemical process. The process is regenerable, employing sodium sulfite wet scrubbing, thermal regeneratio...

40 CFR 60.343 - Monitoring of emissions and operations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... device for the continuous measurement of the pressure loss of the gas stream through the scrubber. The monitoring device must be accurate within ±250 pascals (one inch of water). (2) A monitoring device for continuous measurement of the scrubbing liquid supply pressure to the control device. The monitoring device...

40 CFR 266.105 - Standards to control particulate matter.

Code of Federal Regulations, 2011 CFR

2011-07-01

... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...

40 CFR 266.105 - Standards to control particulate matter.

Code of Federal Regulations, 2013 CFR

2013-07-01

... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...

40 CFR 266.105 - Standards to control particulate matter.

Code of Federal Regulations, 2012 CFR

2012-07-01

... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...

40 CFR 266.105 - Standards to control particulate matter.

Code of Federal Regulations, 2014 CFR

2014-07-01

... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the corrected...

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions... streams, including hazardous waste, fuels, and industrial furnace feed stocks shall not exceed the levels...: terrain-adjusted effective stack height, good engineering practice stack height, terrain type, land use...

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions... streams, including hazardous waste, fuels, and industrial furnace feed stocks shall not exceed the levels...: terrain-adjusted effective stack height, good engineering practice stack height, terrain type, land use...

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions... streams, including hazardous waste, fuels, and industrial furnace feed stocks shall not exceed the levels...: terrain-adjusted effective stack height, good engineering practice stack height, terrain type, land use...

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions... streams, including hazardous waste, fuels, and industrial furnace feed stocks shall not exceed the levels...: terrain-adjusted effective stack height, good engineering practice stack height, terrain type, land use...

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions... streams, including hazardous waste, fuels, and industrial furnace feed stocks shall not exceed the levels...: terrain-adjusted effective stack height, good engineering practice stack height, terrain type, land use...

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... points. (2) Method 2 to determine the volumetric flow rate of the stack gas. (3) Method 3 to determine... matter concentration and volumetric flow rate of the stack gas for positive pressure baghouses without...) Determine the particulate matter concentration and volumetric flow rate using Method 5 or 5D, as applicable...

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... points. (2) Method 2 to determine the volumetric flow rate of the stack gas. (3) Method 3 to determine... matter concentration and volumetric flow rate of the stack gas for positive pressure baghouses without...) Determine the particulate matter concentration and volumetric flow rate using Method 5 or 5D, as applicable...

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... points. (2) Method 2 to determine the volumetric flow rate of the stack gas. (3) Method 3 to determine... matter concentration and volumetric flow rate of the stack gas for positive pressure baghouses without...) Determine the particulate matter concentration and volumetric flow rate using Method 5 or 5D, as applicable...

Efficient control system for low-concentration inorganic gases from a process vent stream: application of surfactants in spray and packed columns.

PubMed

Chein, Hungmin; Aggarwal, Shankar G; Wu, Hsin-Hsien

2004-11-01

Control of low-concentration pollutants from a semiconductor process vent stream using a wet-scrubbing technique is a challenging task to meet Taiwan environmental emission standards. An efficient wet-scrubber is designed on a pilot scale and tested to control low concentration acid and base waste-gas emission. The scrubber system consisted of two columns, i.e., a fine spray column [cutoff diameter (based on volume), Dv(50) = 15.63 microm; Sauter mean diameter (SMD) = 7.62 microm], which is especially efficient for NH3 removal as the pH of the spraying liquid is approximately 7 followed by a packed column with a scrubbing liquid pH approximately 9.0 mainly for acids removal. It is observed that use of the surfactants in low concentration about 10(-4) M and 10(-7) M in the spray liquid and in the scrubbing liquid, respectively, remarkably enhances the removal efficiency of the system. A traditional packed column (without the spray column and the surfactant) showed that the removal efficiencies of NH3, HF, and HCl for the inlet concentration range 0.2 to 3 ppm were (n = 5) 22.6+/-3.4%, 43.4+/-5.5%, and 40.4+/-7.4%, respectively. The overall efficiencies of the proposed system (the spray column and the packed column) in the presence of the surfactant in the spray liquid and in the scrubbing liquid forthese three species were found to increase significantly (n = 5) from 60.3+/-3.6 to 82.8+/-6.8%, 59.1+/-2.7 to 83.4+/-4.2%, and 56.2+/-7.3 to 81.0+/-6.7%, respectively. In this work, development of charge on the gas-liquid interface due to the surfactants has been measured and discussed. It is concluded that the presence of charge on the gas-liquid interface is the responsible factor for enhancement of the removal efficiency (mass-transfer in liquid phase). The effects of the type of surfactants, their chain length, concentration in liquid, etc. on the removal efficiency are discussed. Since the pilot tests were performed under the operating conditions similar to most of the wet-scrubbers operated in semiconductors manufacturing facilities for inorganic pollutants, this study can be applied to modify the existing wet-scrubbers to enhance the removal efficiencies, especially for low-concentration pollutants.

Evaluation of Gas-Cooled Pressurized Phosphoric Acid Fuel Cells for Electric Utility Power Generation

NASA Technical Reports Server (NTRS)

Faroque, M.

1983-01-01

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

Micromotor-Based Biomimetic Carbon Dioxide Sequestration: Towards Mobile Microscrubbers.

PubMed

Uygun, Murat; Singh, Virendra V; Kaufmann, Kevin; Uygun, Deniz A; de Oliveira, Severina D S; Wang, Joseph

2015-10-26

We describe a mobile CO2 scrubbing platform that offers a greatly accelerated biomimetic sequestration based on a self-propelled carbonic anhydrase (CA) functionalized micromotor. The CO2 hydration capability of CA is coupled with the rapid movement of catalytic micromotors, and along with the corresponding fluid dynamics, results in a highly efficient mobile CO2 scrubbing microsystem. The continuous movement of CA and enhanced mass transport of the CO2 substrate lead to significant improvements in the sequestration efficiency and speed over stationary immobilized or free CA platforms. This system is a promising approach to rapid and enhanced CO2 sequestration platforms for addressing growing concerns over the buildup of greenhouse gas. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

KSC-2009-3828

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker examines the location of the quick disconnect on the Ground Umbilical Carrier Plate, or GUCP, being removed from space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3838

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker has removed the seal from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3822

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to remove the 7-inch quick disconnect on the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3824

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove the 7-inch quick disconnect on the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3823

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove the 7-inch quick disconnect on the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3825

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove the 7-inch quick disconnect on the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3837

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker has removed the seal from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3836

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker removes the seal from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3827

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers remove the 7-inch quick disconnect from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3826

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, a worker has removed the 7-inch quick disconnect from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-3835

NASA Image and Video Library

2009-06-24

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, workers prepare to remove the seal from the Ground Umbilical Carrier Plate, or GUCP, on space shuttle Endeavour's external fuel tank. A hydrogen leak at the location during tanking for the STS-127 mission caused the launch attempts to be scrubbed on June 13 and June 17. The GUCP will be examined to determine the cause of the hydrogen leak and repaired. The GUCP is the overboard vent to the pad and the flame stack where the vented hydrogen is burned off. Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT. Photo credit: NASA/Jack Pfaller

KSC-2009-2026

NASA Image and Video Library

2009-03-11

CAPE CANAVERAL, Fla. – Seen in the photo is the hydrogen vent line attached to the Ground Umbilical Carrier Plate on space shuttle Discovery's external fuel tank. The shuttle is on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the location during tanking caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

Season-dependent and independent responses of Mediterranean scrub to light conditions.

PubMed

Zunzunegui, María; Díaz-Barradas, Mari Cruz; Jáuregui, Juan; Rodríguez, Herminia; Álvarez-Cansino, Leonor

2016-05-01

Semi-arid plant species cope with excess of solar radiation with morphological and physiological adaptations that assure their survival when other abiotic stressors interact. At the leaf level, sun and shade plants may differ in the set of traits that regulate environmental stressors. Here, we evaluated if leaf-level physiological seasonal response of Mediterranean scrub species (Myrtus communis, Halimium halimifolium, Rosmarinus officinalis, and Cistus salvifolius) depended on light availability conditions. We aimed to determine which of these responses prevailed independently of the marked seasonality of Mediterranean climate, to define a leaf-level strategy in the scrub community. Thirty six leaf response variables - involving gas exchange, water status, photosystem II photochemical efficiency, photosynthetic pigments and leaf structure - were seasonally measured in sun exposed and shaded plants under field conditions. Physiological responses showed a common pattern throughout the year, in spite of the marked seasonality of the Mediterranean climate and of species-specific differences in the response to light intensity. Variables related to light use, CO2 assimilation, leaf pigment content, and LMA (leaf mass area) presented differences that were consistent throughout the year, although autumn was the season with greater contrast between sun and shade plants. Our data suggest that in Mediterranean scrub shade plants the lutein pool could have an important role in the photoprotection of the photosynthetic tissues. There was a negative linear correlation between the ratio lutein/total chlorophylls and the majority of leaf level variables. The combined effect of abiotic stress factors (light and drought or light and cold) was variable-specific, in some cases enhancing differences between sun and shade plants, while in others leading to unified strategies in all scrub species. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

[Analysis on Mechanism of Rainout Carried by Wet Stack of Thermal Power Plant].

PubMed

Ouyang, Li-hua; Zhuang, Ye; Liu, Ke-wei; Chen, Zhen-yu; Gu, Peng

2015-06-01

Rainout from wet-stack took placed in many thermal power plants with WFGD system. Research on causes of the rainout is important to solve the problem. The objective of this research is to analyze the mechanism of rainout. Field study was performed to collect experimental data in one thermal power plant, including the amount of desulfurization slurry carried by wet flue gas, liquor condensate from wet duct, and droplets from the wet stack. Source apportionment analysis was carried out based on physical and chemical data of liquid sample and solid sample. The result showed that mist eliminator operated well, which met the performance guarantee value. But the total amount of desulfurization slurry in flue gas and the sulfate concentration in liquid condensate discharge from the wet duct/stack increased. The liquid condensate accumulated in the wet duct/stack led to liquid re-entrainment. In conclusion, the rainout in this power plant was caused by the short of wet ductwork or liquid discharge system, the droplets caused by re-entrainment carried by the saturated gas released from the stack. The main undissolved components of the rainout were composite carbonate and aluminosilicate. Although ash concentration in this WFGD met the regulation criteria, source apportionment analysis showed that fly ash contributed to rainout was accounted for 60%. This percentage value was same as the data of solid particles in the condensate. It is important to optimize the wet ductwork, wet stack liner, liquid collectors and drainage. Avoiding the accumulation from saturated vapor thermal condensation is an effective way to solve the wet stack rainout.

IET exhaust gas stack. Section, west elevation, foundation plan, access ...

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

IET exhaust gas stack. Section, west elevation, foundation plan, access ladder, airplane warning light. Ralph M. Parsons 902-5-ANP-712-S 433. Date: May 1954. Approved by INEEL Classification Office for public release. INEEL index code no. 035-0712-60-693-106984 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

30 CFR 250.442 - What are the requirements for a subsea BOP stack?

Code of Federal Regulations, 2010 CFR

2010-07-01

... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...) When you drill with a subsea BOP stack, you must install the BOP system before drilling below surface casing. The District Manager may require you to install a subsea BOP system before drilling below the...

40 CFR 75.15 - Special provisions for measuring Hg mass emissions using the excepted sorbent trap monitoring...

Code of Federal Regulations, 2010 CFR

2010-07-01

... the excepted sorbent trap monitoring methodology. For an affected coal-fired unit under a State or...; (c) A certified flow monitoring system is required; (d) Correction for stack gas moisture content is... proportional to the stack gas volumetric flow rate. (f) At the beginning and end of each sample collection...

Control system adds to precipitator efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gurrole, G.

1978-02-01

An electrostatic precipitator in use at Lion Oil Co., Martinez, Calif., in a fluid catalytic cracking and CO boiler application, was upgraded by mechanical sectionalization of the gas passage and a new electronic control system. The electrostatic precipitator is installed upstream of the CO boiler to handle gas flow up to 4.77 ft/sec, and pressure to 4.5 psi. The independent gas chambers in the electrostatic precipitator were divided by installing gas-tight partition walls to form a total of four electrostatic fields. The precipitator was also equipped with adjustable inlet gas flow-control baffles for even gas distribution. Rows of grounded collectingmore » electrodes are parallel with the flow of gas. The emitting electrode system, powered by separate high-energy transformers for each collecting field, uses silicon-controlled rectifiers and analog electronic networks for rapid response to changing gas and dust conditions. Regulatory requirements call for efficient collection of catalyst fines with no more than 40 lb/hr escaping through the boiler stack. Currently, stack losses average about 38 lb/hr. The installation of two additional control systems with transformers and rectifiers should reduce stack losses to 34 lb/hr.« less

Improve Your Boiler's Combustion Efficiency: Office of Industrial Technologies (OIT) Steam Energy Tips No.4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2002-03-01

Operating your boiler with an optimum amount of excess air will minimize heat loss up the stack and improve combustion efficiency. Combustion efficiency is a measure of how effectively the heat content of a fuel is transferred into usable heat. The stack temperature and flue gas oxygen (or carbon dioxide) concentrations are primary indicators of combustion efficiency. Given complete mixing, a precise or stoichiometric amount of air is required to completely react with a given quantity of fuel. In practice, combustion conditions are never ideal, and additional or ''excess'' air must be supplied to completely burn the fuel. The correctmore » amount of excess air is determined from analyzing flue gas oxygen or carbon dioxide concentrations. Inadequate excess air results in unburned combustibles (fuel, soot, smoke, and carbon monoxide) while too much results in heat lost due to the increased flue gas flow--thus lowering the overall boiler fuel-to-steam efficiency. The table relates stack readings to boiler performance. On well-designed natural gas-fired systems, an excess air level of 10% is attainable. An often stated rule of thumb is that boiler efficiency can be increased by 1% for each 15% reduction in excess air or 40 F reduction in stack gas temperature.« less

The thermal stability of Pt/epitaxial Gd2O3/Si stacks and its dependence on heat-treatment ambient

NASA Astrophysics Data System (ADS)

Lipp, E.; Osten, H. J.; Eizenberg, M.

2009-12-01

The stability of Pt/epitaxial Gd2O3/Si stacks is studied by monitoring the chemical and electrical properties following heat treatments in forming gas and in vacuum at temperatures between 400 and 650 °C. Our results show that stack instability is realized via diffusion of Gd through the Pt grain boundaries, which was observed after forming-gas annealing at 550 °C for 30 min. The Gd diffusion kinetics in forming gas is studied by secondary ion mass spectrometry analysis, showing that the diffusion process occurs according to C-type kinetics with an activation energy of 0.73±0.04 eV. Following vacuum heat treatments at 600 °C for 30 min, Si outdiffusion is observed, in addition to Gd outdiffusion. Si outdiffusion results in the formation of PtSi clusters on the metal surface following vacuum annealing at 650 °C. In contrast, in the case of forming-gas treatments, Si diffusion and silicide formation were detected only after annealing at 700 °C. The better stability of Pt/Gd2O3/Si stacks in forming gas is correlated with the content of oxygen in the Pt layer during the treatment.

Natural gas availability and ambient air quality in the Baton Rouge/New Orleans industrial complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fieler, E.R.; Harrison, D.P.

1978-02-26

Three scenarios were modeled for the Baton Rouge/New Orleans area for 1985: one assumes the substitution of residual oil (0.7% sulfur) for gas to decrease gas-burning stationary sources from 80 to 8% and the use of properly designed stacks for large emitters; the second makes identical gas supply assumptions but adds proper stack dispersion for medium as well as large emitters; and the third is based on 16% gas-burning stationary sources. The Climatological Dispersion Model was used to translate (1974) emission rates into ambient air concentrations. Growth rates for residential, commercial, and transportation sources, but not industry, were considered. Themore » results show that proper policies, which would require not only tall stacks for large oil burning units (and for intermediate units also in the areas of high industrial concentration), but also the careful location of new plants would permit continued industrial expansion without severe air pollution problems.« less

Gas sensor

DOEpatents

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

2014-09-09

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

Use of sulfide-containing liquors for removing mercury from flue gases

DOEpatents

Nolan, Paul S.; Downs, William; Bailey, Ralph T.; Vecci, Stanley J.

2006-05-02

A method and apparatus for reducing and removing mercury in industrial gases, such as a flue gas, produced by the combustion of fossil fuels, such as coal, adds sulfide ions to the flue gas as it passes through a scrubber. Ideally, the source of these sulfide ions may include at least one of: sulfidic waste water, kraft caustic liquor, kraft carbonate liquor, potassium sulfide, sodium sulfide, and thioacetamide. The sulfide ion source is introduced into the scrubbing liquor as an aqueous sulfide species. The scrubber may be either a wet or dry scrubber for flue gas desulfurization systems.

Use of sulfide-containing liquors for removing mercury from flue gases

DOEpatents

Nolan, Paul S.; Downs, William; Bailey, Ralph T.; Vecci, Stanley J.

2003-01-01

A method and apparatus for reducing and removing mercury in industrial gases, such as a flue gas, produced by the combustion of fossil fuels, such as coal, adds sulfide ions to the flue gas as it passes through a scrubber. Ideally, the source of these sulfide ions may include at least one of: sulfidic waste water, kraft caustic liquor, kraft carbonate liquor, potassium sulfide, sodium sulfide, and thioacetamide. The sulfide ion source is introduced into the scrubbing liquor as an aqueous sulfide species. The scrubber may be either a wet or dry scrubber for flue gas desulfurization systems.

Development of on-site PAFC stacks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hotta, K.; Matsumoto, Y.; Horiuchi, H.

1996-12-31

PAFC (Phosphoric Acid Fuel Cell) has been researched for commercial use and demonstration plants have been installed in various sites. However, PAFC don`t have a enough stability yet, so more research and development must be required in the future. Especially, cell stack needs a proper state of three phases (liquid, gas and solid) interface. It is very difficult technology to keep this condition for a long time. In the small size cell with the electrode area of 100 cm{sup 2}, gas flow and temperature distributions show uniformity. But in the large size cell with the electrode area of 4000 cm{supmore » 2}, the temperature distributions show non-uniformity. These distributions would cause to be shorten the cell life. Because these distributions make hot-spot and gas poverty in limited parts. So we inserted thermocouples in short-stack for measuring three-dimensional temperature distributions and observed effects of current density and gas utilization on temperature.« less

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

NASA Astrophysics Data System (ADS)

Kavalis, A. E.

1983-06-01

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

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

NASA Technical Reports Server (NTRS)

Nainiger, J. J.

1980-01-01

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

Exhaust gas clean up process

DOEpatents

Walker, Richard J.

1989-01-01

A method of cleaning an exhaust gas containing particulates, SO.sub.2 and NO.sub.x includes prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO.sub.x and SO.sub.2, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO.sub.x is removed as N.sub.2 or nitrogen-sulfonate ions and the oxides of sulfur are removed as a vaulable sulfate salt.

Gas separation by composite solvent-swollen membranes

DOEpatents

Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

1989-04-25

There is disclosed a composite immobilized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorus or sulfur atom, and having a boiling point of at least 100 C and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation. 3 figs.

Gas separation by composite solvent-swollen membranes

DOEpatents

Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

1989-01-01

There is disclosed a composite immobulized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorous or sulfur atom, and having a boiling point of at least 100.degree. C. and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation.

Nebulization Reflux Concentrator

NASA Technical Reports Server (NTRS)

Cofer, Wesley R., III; Collins, V. G.

1986-01-01

Nebulization reflux concentrator extracts and concentrates trace quantities of water-soluble gases for subsequent chemical analysis. Hydrophobic membrane and nebulizing nozzles form scrubber for removing trace quantities of soluble gases or other contaminants from atmosphere. Although hydrophobic membrane virtually blocks all transport of droplets, it offers little resistance to gas flow; hence, device permits relatively large volumes of gas scrubbed efficiently with very small volumes of liquid. This means analyzable quantities of contaminants concentrate in extracting solutions in much shorter times than with conventional techniques.

40 CFR 60.403 - Monitoring of emissions and operations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... measurement of the pressure loss of the gas stream through the scrubber. The monitoring device must be certified by the manufacturer to be accurate within ±250 pascals (±1 inch water) gauge pressure. (2) A monitoring device for the continuous measurement of the scrubbing liquid supply pressure to the control...

PILOT-SCALE PARAMETRIC TESTING OF SPRAY DRYER SO2 SCRUBBER FOR LOW-TO-MODERATE SULFUR COAL UTILITY APPLICATIONS

EPA Science Inventory

The report gives results of a comprehensive, pilot, dry, SO2 scrubbing test program to determine the effects of process variables on SO2 removal. In the spray dryer, stoichiometric ratio, flue gas temperature approach to adiabatic saturation, and temperature drop across the spray...

40 CFR 60.385 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... performance test of a wet scrubber, and at least weekly thereafter, the owner or operator shall record the measurements of both the change in pressure of the gas stream across the scrubber and the scrubbing liquid flow rate. (c) After the initial performance test of a wet scrubber, the owner or operator shall submit...

40 CFR 60.385 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... performance test of a wet scrubber, and at least weekly thereafter, the owner or operator shall record the measurements of both the change in pressure of the gas stream across the scrubber and the scrubbing liquid flow rate. (c) After the initial performance test of a wet scrubber, the owner or operator shall submit...

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

PubMed

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

2015-01-01

Identifying marker congeners of unintentionally produced polychlorinated naphthalenes (PCNs) from industrial thermal sources might be useful for predicting total PCN (∑2-8PCN) emissions by the determination of only indicator congeners. In this study, potential indicator congeners were identified based on the PCN data in 122 stack gas samples from over 60 plants involved in more than ten industrial thermal sources reported in our previous case studies. Linear regression analyses identified that the concentrations of CN27/30, CN52/60, and CN66/67 correlated significantly with ∑2-8PCN (R(2)=0.77, 0.80, and 0.58, respectively; n=122, p<0.05), which might be good candidates for indicator congeners. Equations describing relationships between indicators and ∑2-8PCN were established. The linear regression analyses involving 122 samples showed that the relationships between the indicator congeners and ∑2-8PCN were not significantly affected by factors such as industry types, raw materials used, or operating conditions. Hierarchical cluster analysis and similarity calculations for the 122 stack gas samples were adopted to group those samples and evaluating their similarity and difference based on the PCN homolog distributions from different industrial thermal sources. Generally, the fractions of less chlorinated homologs comprised of di-, tri-, and tetra-homologs were much higher than that of more chlorinated homologs for up to 111 stack gas samples contained in group 1 and 2, which indicating the dominance of lower chlorinated homologs in stack gas from industrial thermal sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

76. General view looking east showing Rust Co. boiler stacks ...

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

76. General view looking east showing Rust Co. boiler stacks at left, Babcock & Wilcox type boiler stacks at right, Dovel horizontal gas washer in foreground, and No. 1 Furnace in distance. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

Cocurrent scrubber evaluation: TVA's Colbert lime-limestone wet-scrubbing pilot plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hollinden, G.A.; Robards, R.F.; Moore, N.D.

1979-01-01

The Tennessee Valley Authority (TVA) is actively engaged in a pilot plant program to develop and/or evaluate wet-scrubbing processes for removing sulfur dioxide (SO/sub 2/) from boiler flue gas. The physical size and general arrangement of flue gas scrubbing systems have a major impact on capital investment and operating cost, as do potential operating and maintenance advantages inherent to some systems. The equipment configuration for a cocurrent scrubber reflects some of these advantages. EPRI funded TVA to perform preliminary screening tests at TVA's 1 MW pilot plant (Colbert Steam Plant) to develop operating data on the cocurrent design for usemore » in designing and operating a 10 MW prototype cocurrent scrubber at TVA's Shawnee Scrubber Test Facility. Results of Colbert tests showed excellent sulfur dioxide removal efficiencies, generally greater than 85%, low pressure drop, and high particulate removal efficiencies. This report covers these screening tests. The results indicate that commercial application of the cocurrent scrubber concept may save substantial capital investment by reducing the number of scrubber modules and auxiliary equipment. These evaluation tests provided the basis for the design and construction of the 10 MW cocurrent scrubber at the Shawnee Facility. Operation of this scrubber began in August 1978 to develop the scale-up similarities and differences between the Colbert test program (1 MW) and the Shawnee test program (10 MW). It also demonstrated the practicality and reliability of the 10 MW prototype. Detailed results of the prototype test series will be available in late 1979.« less

30 CFR 250.441 - What are the requirements for a surface BOP stack?

Code of Federal Regulations, 2010 CFR

2010-07-01

... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...? (a) When you drill with a surface BOP stack, you must install the BOP system before drilling below... with blind-shear rams. The blind-shear rams must be capable of shearing the drill pipe that is in the...

30 CFR 250.416 - What must I include in the diverter and BOP descriptions?

Code of Federal Regulations, 2010 CFR

2010-07-01

... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Applying for A Permit to Drill § 250.416 What must I include in the diverter and BOP descriptions? You must... rams installed in the BOP stack (both surface and subsea stacks) are capable of shearing the drill pipe...

Variability of passive gas emissions, seismicity, and deformation during crater lake growth at White Island Volcano, New Zealand, 2002-2006

NASA Astrophysics Data System (ADS)

Werner, C.; Hurst, T.; Scott, B.; Sherburn, S.; Christenson, B. W.; Britten, K.; Cole-Baker, J.; Mullan, B.

2008-01-01

We report on 4 years of airborne measurements of CO2, SO2, and H2S emission rates during a quiescent period at White Island volcano, New Zealand, beginning in 2003. During this time a significant crater lake emerged, allowing scrubbing processes to be investigated. CO2 emissions varied from a baseline of 250 to >2000 t d-1 and demonstrated clear annual cycling that was consistent with numbers of earthquake detections and annual changes in sea level. The annual variability was found to be most likely related to increases in the strain on the volcano during sea level highs, temporarily causing fractures to reduce in size in the upper conduit. SO2 emissions varied from 0 to >400 t d-1 and were clearly affected by scrubbing processes within the first year of lake development. Scrubbing caused increases of SO42- and Cl- in lake waters, and the ratio of carbon to total sulphur suggested that elemental sulphur deposition was also significant in the lake during the first year. Careful measurements of the lake level and chemistry allowed estimates of the rate of H2O(g) and HCl(g) input into the lake and suggested that the molar abundances of major gas species (H2O, CO2, SO2, and HCl) during this quiescent phase were similar to fumarolic ratios observed between earlier eruptive periods. The volume of magma estimated from CO2 emissions (0.015-0.04 km3) was validated by Cl- increases in the lake, suggesting that the gas and magma are transported from deep to shallow depths as a closed system and likely become open in the upper conduit region. The absence of surface deformation further leads to a necessity of magma convection to supply and remove magma from the degassing depths. Two models of convection configurations are discussed.

UTC Power/Delphi SECA CBS Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorman, Michael; Kerr, Rich

2013-04-04

The subject report summarizes the results of solid oxide fuel cell development conducted by UTC Power in conjunction with Delphi Automotive Systems under a cost-share program with from October 2008 through March of 2013. Over that period Delphi Automotive Systems developed a nearly four times larger area solid oxide fuel cell stack capable of operating on pre-reformed natural gas and simulated coal gas with durability demonstrated to 5,000 hours and projected to exceed 10,000 hours. The new stack design was scaled to 40-cell stacks with power output in excess of 6.25kW. Delphi also made significant strides in improving the manufacturability,more » yield and production cost of these solid oxide fuel cells over the course of the program. Concurrently, UTC Power developed a conceptual design for a 120 MW Integrated Gasification Fuel Cell (IGFC) operating on coal syngas with as high as 57% Higher Heating Value (HHV) efficiency as a measure of the feasibility of the technology. Subsequently a 400 kW on-site system preliminary design with 55% Lower Heating Value (LHV) efficiency operating on natural gas was down-selected from eighteen candidate designs. That design was used as the basis for a 25kW breadboard power plant incorporating four Delphi cell stacks that was tested on natural gas before the program was discontinued due to the sale of UTC Power in early 2013. Though the program was cut short of the endurance target of 3,000 hours, many aspects of the technology were proven including: large-area, repeatable cell manufacture, cell stack operation on simulated coal gas and natural gas and integrated power plant operation on natural gas. The potential of the technology for high efficiency stationary electric power generation is clear. Acceptable production costs, durability, and reliability in real world environments are the remaining challenges to commercialization.« less

Cell module and fuel conditioner development

NASA Technical Reports Server (NTRS)

Hoover, D. Q., Jr.

1982-01-01

The phosphoric acid fuel cell module (stack) development which culminated in an 80 cell air-cooled stack with separated gas cooling and treed cooling plates is described. The performance of the 80 cell stack was approx. 100 mV per cell higher than that attained during phase 1. The components and materials performed stably for over 8000 hours in a 5 cell stack. The conceptual design of a fuel conditioning system is described.

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, January--March 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration. During the 6 months of scheduled operations period, expected to begin January 1992, data will be collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the absorber; Make-up reagent rates; Product quality including concentrations and compositions; System integration and control philosophy; and Membrane stability and performance with respect to foulants.« less

A high-dispersion molecular gas component in nearby galaxies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caldú-Primo, Anahi; Walter, Fabian; Sandstrom, Karin

2013-12-01

We present a comprehensive study of the velocity dispersion of the atomic (H I) and molecular (H{sub 2}) gas components in the disks (R ≲ R {sub 25}) of a sample of 12 nearby spiral galaxies with moderate inclinations. Our analysis is based on sensitive high-resolution data from the THINGS (atomic gas) and HERACLES (molecular gas) surveys. To obtain reliable measurements of the velocity dispersion, we stack regions several kiloparsecs in size, after accounting for intrinsic velocity shifts due to galactic rotation and large-scale motions. We stack using various parameters: the galactocentric distance, star formation rate surface density, H Imore » surface density, H{sub 2} surface density, and total gas surface density. We fit single Gaussian components to the stacked spectra and measure median velocity dispersions for H I of 11.9 ± 3.1 km s{sup –1} and for CO of 12.0 ± 3.9 km s{sup –1}. The CO velocity dispersions are thus, surprisingly, very similar to the corresponding ones of H I, with an average ratio of σ{sub HI}/σ{sub CO}= 1.0 ± 0.2 irrespective of the stacking parameter. The measured CO velocity dispersions are significantly higher (factor of ∼2) than the traditional picture of a cold molecular gas disk associated with star formation. The high dispersion implies an additional thick molecular gas disk (possibly as thick as the H I disk). Our finding is in agreement with recent sensitive measurements in individual edge-on and face-on galaxies and points toward the general existence of a thick disk of molecular gas, in addition to the well-known thin disk in nearby spiral galaxies.« less

Stack gas treatment

DOEpatents

Reeves, Adam A.

1977-04-12

Hot stack gases transfer contained heat to a gravity flow of pebbles treated with a catalyst, cooled stacked gases and a sulfuric acid mist is withdrawn from the unit, and heat picked up by the pebbles is transferred to air for combustion or other process. The sulfuric acid (or sulfur, depending on the catalyst) is withdrawn in a recovery unit.

40 CFR Table 5 to Subpart Ddddd of... - Performance Testing Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... 2G in appendix A to part 60 of this chapter. c. Determine oxygen and carbon dioxide concentrations of...) (IBR, see § 63.14(i)). d. Measure the moisture content of the stack gas Method 4 in appendix A to part... stack gas Method 2, 2F, or 2G in appendix A to part 60 of this chapter. c. Determine oxygen and carbon...

Exploration of SO[subscript 2] Scrubbers: An Environmental Chemistry Project

ERIC Educational Resources Information Center

Schilling, Amber L.; Leber, Phyllis A.; Yoder, Claude H.

2009-01-01

The remediation of acid rain by SO[subscript 2] scrubbing is integrated into a laboratory project appropriate for first-year chemistry students. By burning a small amount of sulfur and bubbling the gas produced through distilled water, the student first observes one of the reactions that produces acid rain. The student then tests four different…

40 CFR Table 24 to Subpart Uuu of... - Continuous Monitoring Systems for Inorganic HAP Emissions From Catalytic Reforming Units

Code of Federal Regulations, 2011 CFR

2011-07-01

... entering the scrubber during coke burn-off and catalyst rejuvenation; and continuous parameter monitoring system to measure and record gas flow rate entering or exiting the scrubber during coke burn-off and... alkalinity of the water (or scrubbing liquid) exiting the scrubber during coke burn-off and catalyst...

KSC-2009-2027

NASA Image and Video Library

2009-03-11

CAPE CANAVERAL, Fla. – A closeup of the 7-inch quick disconnect that will be replaced on the hydrogen vent line to the Ground Umbilical Carrier Plate of space shuttle Discovery's external fuel tank. The replacement will be made on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the site during fueling caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

Fuel cell separator with compressible sealing flanges

DOEpatents

Mientek, A.P.

1984-03-30

A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

Fuel cell separator with compressible sealing flanges

DOEpatents

Mientek, Anthony P.

1985-04-30

A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

Functional Groups Based on Leaf Physiology: Are they Spatially and Temporally Robust?

NASA Technical Reports Server (NTRS)

Foster, Tammy E.; Brooks, J. Renee

2004-01-01

The functional grouping hypothesis, which suggests that complexity in ecosystem function can be simplified by grouping species with similar responses, was tested in the Florida scrub habitat. Functional groups were identified based on how species in fire maintained Florida scrub regulate exchange of carbon and water with the atmosphere as indicated by both instantaneous gas exchange measurements and integrated measures of function (%N, delta C-13, delta N-15, C-N ratio). Using cluster analysis, five distinct physiologically-based functional groups were identified in the fire maintained scrub. These functional groups were tested to determine if they were robust spatially, temporally, and with management regime. Analysis of Similarities (ANOSIM), a non-parametric multivariate analysis, indicated that these five physiologically-based groupings were not altered by plot differences (R = -0.115, p = 0.893) or by the three different management regimes; prescribed burn, mechanically treated and burn, and fire-suppressed (R = 0.018, p = 0.349). The physiological groupings also remained robust between the two climatically different years 1999 and 2000 (R = -0.027, p = 0.725). Easy-to-measure morphological characteristics indicating functional groups would be more practical for scaling and modeling ecosystem processes than detailed gas-exchange measurements, therefore we tested a variety of morphological characteristics as functional indicators. A combination of non-parametric multivariate techniques (Hierarchical cluster analysis, non-metric Multi-Dimensional Scaling, and ANOSIM) were used to compare the ability of life form, leaf thickness, and specific leaf area classifications to identify the physiologically-based functional groups. Life form classifications (ANOSIM; R = 0.629, p 0.001) were able to depict the physiological groupings more adequately than either specific leaf area (ANOSIM; R = 0.426, p = 0.001) or leaf thickness (ANOSIM; R 0.344, p 0.001). The ability of life forms to depict the physiological groupings was improved by separating the parasitic Ximenia americana from the shrub category (ANOSIM; R = 0.794, p = 0.001). Therefore, a life form classification including parasites was determined to be a good indicator of the physiological processes of scrub species, and would be a useful method of grouping for scaling physiological processes to the ecosystem level.

Cell module and fuel conditioner

NASA Technical Reports Server (NTRS)

Hoover, D. Q., Jr.

1981-01-01

The results of the completed tests on Stack 561 and the on-going tests of 562 (23 cell stacks of the MK-1 and M-2 designs respectively) are reported and their performance is compared. Results of the on-going endurance test of Stack 560 (5 cell, MK-2) are reported. Plans for fabrication of Stacks 563 and 564 (23 cell stacks of the MK-1 and MK-2 design) are summarized. Results of the burner tests are given. Excellent performance was achieved on simulated anode exhaust gas over very wide load and air/fuel ranges.

Fabrication of multiwall carbon nanotube sheet based hydrogen sensor on a stacking multi-layer structure.

PubMed

Yan, Keyi; Toku, Yuhki; Morita, Yasuyuki; Ju, Yang

2018-06-22

In this research, we propose a new simple method to fabricate hydrogen gas sensor by stacking the multiwall carbon nanotube (MWCNT) sheets. MWCNT sheet offers a larger surface area and more CNT contacts, which are key factors for gas sensing, because of its super-high alignment and end-to-end structure comparing to the traditional CNT film. Besides, MWCNT sheet can be directly drawn from the spinnable CNT array in large scales. Therefore, this method is a potential answer for the mass production and commercialization of CNT based sensor with high response. By stacking different layers of sheet, microstructure and CNT interactions in the layers were changed and their influences towards gas sensing were investigated. It was observed that the sample with 3 layers of sheet and functionalized with 3 nm-thick Pd showed the best gas sensing performance with a response of 12.31% at 4% H2 and response time below 200 s. © 2018 IOP Publishing Ltd.

Continuous determination of gaseous ammonia in the ambient atmosphere using fluorescence derivatization

NASA Astrophysics Data System (ADS)

Abbas, Rana; Tanner, Roger L.

A method for continuous determination of ambient ammonia levels employing o-phthalaldehyde fluorescence derivatization is described. A simplified Venturi scrubber and gas-liquid separator have been employed for reproducible measurements of ⩾ 0.1 ppb ambient ammonia with less than 2 min time resolution. The scrubbing efficiency of the ammonia gas collection system was determined to be 29 ± 1 %. During 4 d in August 1979 ambient ammonia levels at the Brookhaven National Laboratory site averaged about 1.5 ± 1.1 ppb during afternoon daylight hours.

Cryolite process for the solidification of radioactive wastes

DOEpatents

Wielang, Joseph A.; Taylor, Larry L.

1976-01-01

An improved method is provided for solidifying liquid wastes containing significant quantities of sodium or sodium compounds by calcining in a fluidized-bed calciner. The formation of sodium nitrate which will cause agglomeration of the fluidized-bed particles is retarded by adding aluminum and a fluoride to the waste in order to produce cryolite during calcination. The off-gas of the calciner is scrubbed with a solution containing aluminum in order to complex any fluoride which may be liberated by subsequent dissolution of cryolite and prevent corrosion in the off-gas cleanup system.

In-ground operation of Geothermic Fuel Cells for unconventional oil and gas recovery

NASA Astrophysics Data System (ADS)

Sullivan, Neal; Anyenya, Gladys; Haun, Buddy; Daubenspeck, Mark; Bonadies, Joseph; Kerr, Rick; Fischer, Bernhard; Wright, Adam; Jones, Gerald; Li, Robert; Wall, Mark; Forbes, Alan; Savage, Marshall

2016-01-01

This paper presents operating and performance characteristics of a nine-stack solid-oxide fuel cell combined-heat-and-power system. Integrated with a natural-gas fuel processor, air compressor, reactant-gas preheater, and diagnostics and control equipment, the system is designed for use in unconventional oil-and-gas processing. Termed a ;Geothermic Fuel Cell; (GFC), the heat liberated by the fuel cell during electricity generation is harnessed to process oil shale into high-quality crude oil and natural gas. The 1.5-kWe SOFC stacks are packaged within three-stack GFC modules. Three GFC modules are mechanically and electrically coupled to a reactant-gas preheater and installed within the earth. During operation, significant heat is conducted from the Geothermic Fuel Cell to the surrounding geology. The complete system was continuously operated on hydrogen and natural-gas fuels for ∼600 h. A quasi-steady operating point was established to favor heat generation (29.1 kWth) over electricity production (4.4 kWe). Thermodynamic analysis reveals a combined-heat-and-power efficiency of 55% at this condition. Heat flux to the geology averaged 3.2 kW m-1 across the 9-m length of the Geothermic Fuel Cell-preheater assembly. System performance is reviewed; some suggestions for improvement are proposed.

Emission and distribution of PCDD/Fs, chlorobenzenes, chlorophenols, and PAHs from stack gas of a fluidized bed and a stoker waste incinerator in China.

PubMed

Wang, Tianjiao; Chen, Tong; Lin, Xiaoqing; Zhan, Mingxiu; Li, Xiaodong

2017-02-01

The concentrations, homologue, and congener profiles, as well as the gas/particle distribution of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), chlorobenzenes (CBzs), chlorophenols (CPhs), and polyaromatic hydrocarbons (PAHs) from stack gas of two different municipal solid waste incinerators in China, were characterized. The incinerators were a stoker furnace incinerator equipped with the advanced air pollution control device (APCD) and a common circulating fluidized bed (CFB) furnace. The concentration of PCDD/Fs in the stack gas of the stoker incinerator ranged 0.011-0.109 ng international toxic equivalent factor (I-TEQ)/Nm 3 and was below the current limit for PCDD/F emissions from the municipal solid waste incinerators (MSWIs) in China (0.1 ng I-TEQ/Nm 3 ) in most of the cases. Moreover, the concentration of PCDD/Fs in the stack gas of the stoker incinerator was significantly lower than that of the CFB incinerator (0.734 to 24.6 ng I-TEQ/Nm 3 ). In both incinerators, the majority of the total PCDD/F emissions (above 90%) ended up in the gas phase. 2,3,4,7,8-PeCDF, which occupied 24.3-43.6 and 32.5-75.6% of I-TEQ contribution in MSWIs A and B, respectively, was the most abundant congener. However, different types of incinerators and APCDs induced different congener and homologue distributions. The total concentration of CBzs from the stoker incinerator (0.05-3.2 μg/Nm 3 ) was also much lower than that formed from the CFB incinerator (10.9-75.2 μg/Nm 3 ). The phase distribution of CBzs followed the same pattern as with the PCDD/Fs. Moreover, the emission level of CBz was 100-1000 times higher than that of the PCDD/Fs, which determines the applicability of CBzs as indicators of PCDD/F emissions. High correlations between the emission concentrations of PCDD/Fs, TeCBz, and PCBz in specific ranges were revealed. Furthermore, high concentrations of CPhs (0.6-141.0 μg/Nm 3 ) and PAHs (148.6-4986.5 μg/Nm 3 ) were detected in the stack gases of MSWI B. In some cases, the concentrations were as high as the concentrations in the fumes exiting the boiler of one foreign stoker without flue gas purification indicating the abundance of CPh and PAH emissions in the stack gas of waste incinerators.

Solid State Energy Conversion Energy Alliance (SECA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hennessy, Daniel; Sibisan, Rodica; Rasmussen, Mike

2011-09-12

The overall objective is to develop a Solid Oxide Fuel Cell (SOFC) stack that can be economically produced in high volumes and mass customized for different applications in transportation, stationary power generation, and military market sectors. In Phase I, work will be conducted on system design and integration, stack development, and development of reformers for natural gas and gasoline. Specifically, Delphi-Battelle will fabricate and test a 5 kW stationary power generation system consisting of a SOFC stack, a steam reformer for natural gas, and balance-of-plant (BOP) components, having an expected efficiency of ≥ 35 percent (AC/LHV). In Phase II andmore » Phase III, the emphasis will be to improve the SOFC stack, reduce start-up time, improve thermal cyclability, demonstrate operation on diesel fuel, and substantially reduce materials and manufacturing cost by integrating several functions into one component and thus reducing the number of components in the system. In Phase II, Delphi-Battelle will fabricate and demonstrate two SOFC systems: an improved stationary power generation system consisting of an improved SOFC stack with integrated reformation of natural gas, and the BOP components, with an expected efficiency of ≥ 40 percent (AC/LHV), and a mobile 5 kW system for heavy-duty trucks and military power applications consisting of an SOFC stack, reformer utilizing anode tailgate recycle for diesel fuel, and BOP components, with an expected efficiency of ≥ 30 percent (DC/LHV). Finally, in Phase III, Delphi-Battelle will fabricate and test a 5 kW Auxiliary Power Unit (APU) for mass-market automotive application consisting of an optimized SOFC stack, an optimized catalytic partial oxidation (CPO) reformer for gasoline, and BOP components, having an expected efficiency of ≥ 30 percent (DC/LHV) and a factory cost of ≤ $400/kW.« less

Solid State Energy Conversion Energy Alliance (SECA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hennessy, Daniel; Sibisan, Rodica; Rasmussen, Mike

2011-09-12

The overall objective is to develop a solid oxide fuel cell (SOFC) stack that can be economically produced in high volumes and mass customized for different applications in transportation, stationary power generation, and military market sectors. In Phase I, work will be conducted on system design and integration, stack development, and development of reformers for natural gas and gasoline. Specifically, Delphi-Battelle will fabricate and test a 5 kW stationary power generation system consisting of a SOFC stack, a steam reformer for natural gas, and balance-of-plant (BOP) components, having an expected efficiency of 35 percent (AC/LHV). In Phase II and Phasemore » III, the emphasis will be to improve the SOFC stack, reduce start-up time, improve thermal cyclability, demonstrate operation on diesel fuel, and substantially reduce materials and manufacturing cost by integrating several functions into one component and thus reducing the number of components in the system. In Phase II, Delphi-Battelle will fabricate and demonstrate two SOFC systems: an improved stationary power generation system consisting of an improved SOFC stack with integrated reformation of natural gas, and the BOP components, with an expected efficiency of ≥40 percent (AC/LHV), and a mobile 5 kW system for heavy-duty trucks and military power applications consisting of an SOFC stack, reformer utilizing anode tailgate recycle for diesel fuel, and BOP components, with an expected efficiency of ≥30 percent (DC/LHV). Finally, in Phase III, Delphi-Battelle will fabricate and test a 5 kW Auxiliary Power Unit (APU) for mass-market automotive application consisting of an optimized SOFC stack, an optimized catalytic partial oxidation (CPO) reformer for gasoline, and BOP components, having an expected efficiency of 30 percent (DC/LHV) and a factory cost of ≤$400/kW.« less

Dynamic model of a micro-tubular solid oxide fuel cell stack including an integrated cooling system

NASA Astrophysics Data System (ADS)

Hering, Martin; Brouwer, Jacob; Winkler, Wolfgang

2017-02-01

A novel dynamic micro-tubular solid oxide fuel cell (MT-SOFC) and stack model including an integrated cooling system is developed using a quasi three-dimensional, spatially resolved, transient thermodynamic, physical and electrochemical model that accounts for the complex geometrical relations between the cells and cooling-tubes. The modeling approach includes a simplified tubular geometry and stack design including an integrated cooling structure, detailed pressure drop and gas property calculations, the electrical and physical constraints of the stack design that determine the current, as well as control strategies for the temperature. Moreover, an advanced heat transfer balance with detailed radiative heat transfer between the cells and the integrated cooling-tubes, convective heat transfer between the gas flows and the surrounding structures and conductive heat transfer between the solid structures inside of the stack, is included. The detailed model can be used as a design basis for the novel MT-SOFC stack assembly including an integrated cooling system, as well as for the development of a dynamic system control strategy. The evaluated best-case design achieves very high electrical efficiency between around 75 and 55% in the entire power density range between 50 and 550 mW /cm2 due to the novel stack design comprising an integrated cooling structure.

Process for control of pollutants generated during coal gasification

DOEpatents

Frumerman, Robert; Hooper, Harold M.

1979-01-01

The present invention is directed to an improvement in the coal gasification process that effectively eliminates substantially all of the environmental pollutants contained in the producer gas. The raw producer gas is passed through a two-stage water scrubbing arrangement with the tars being condensed essentially water-free in the first stage and lower boiling condensables, including pollutant laden water, being removed in the second stage. The pollutant-laden water is introduced into an evaporator in which about 95 percent of the water is vaporized and introduced as steam into the gas producer. The condensed tars are combusted and the resulting products of combustion are admixed with the pollutant-containing water residue from the evaporator and introduced into the gas producer.

Short protection device for stack of electrolytic cells

DOEpatents

Katz, Murray; Schroll, Craig R.

1985-10-22

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

Modeling and measurement of electrostatic spray behavior in a rectangular throat of Pease-Anthony venturi scrubber.

PubMed

Yang, H T; Viswanathan, S; Balachandran, W; Ray, M B

2003-06-01

This paper presents the simulation and experimental results of the distribution of droplets produced by electrostatic nozzles inside a venturi scrubber. The simulation model takes into account initial liquid momentum, hydrodynamic, gravitational and electric forces, and eddy diffusion. The velocity and concentration profile of charged droplets injected from an electrostatic nozzle in the scrubber under the combined influence of hydrodynamic and electric fields were simulated. The effects of operating parameters, such as gas velocity, diameter of the scrubbing droplets, charge-to-mass ratio, and liquid-to-gas ratio on the distribution of the water droplets within the scrubber, were also investigated. The flux distribution of scrubbing liquid in the presence of electric field is improved considerably over a conventional venturi scrubber, and the effect increases with the increase in charge-to-mass ratio. Improved flux distribution using charged droplets increases the calculated overall collection efficiency of the submicron particles. However, the effect of an electric field on the droplet distribution pattern for small drop sizes in strong hydrodynamic field conditions is negligible. Simulated results are in good agreement with the experimental data obtained in the laboratory.

Advanced Flue Gas Desulfurization (AFGD) Demonstration Project, A DOE Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

National Energy Technology Laboratory

2001-08-31

The AFGD process as demonstrated by Pure Air at the Bailly Station offers a reliable and cost-effective means of achieving a high degree of SO{sub 2} emissions reduction when burning high-sulfur coals. Many innovative features have been successfully incorporated in this process, and it is ready for widespread commercial use. The system uses a single-loop cocurrent scrubbing process with in-situ oxidation to produce wallboard-grade gypsum instead of wet sludge. A novel wastewater evaporation system minimizes effluents. The advanced scrubbing process uses a common absorber to serve multiple boilers, thereby saving on capital through economies of scale. Major results of themore » project are: (1) SO{sub 2} removal of over 94 percent was achieved over the three-year demonstration period, with a system availability exceeding 99.5 percent; (2) a large, single absorber handled the combined flue gas of boilers generating 528 MWe of power, and no spares were required; (3) direct injection of pulverized limestone into the absorber was successful; (4) Wastewater evaporation eliminated the need for liquid waste disposal; and (5) the gypsum by-product was used directly for wallboard manufacture, eliminating the need to dispose of waste sludge.« less

A Markov decision process for managing habitat for Florida scrub-jays

USGS Publications Warehouse

Johnson, Fred A.; Breininger, David R.; Duncan, Brean W.; Nichols, James D.; Runge, Michael C.; Williams, B. Ken

2011-01-01

Florida scrub-jays Aphelocoma coerulescens are listed as threatened under the Endangered Species Act due to loss and degradation of scrub habitat. This study concerned the development of an optimal strategy for the restoration and management of scrub habitat at Merritt Island National Wildlife Refuge, which contains one of the few remaining large populations of scrub-jays in Florida. There are documented differences in the reproductive and survival rates of scrubjays among discrete classes of scrub height (<120 cm or "short"; 120-170 cm or "optimal"; .170 cm or "tall"; and a combination of tall and optimal or "mixed"), and our objective was to calculate a state-dependent management strategy that would maximize the long-term growth rate of the resident scrub-jay population. We used aerial imagery with multistate Markov models to estimate annual transition probabilities among the four scrub-height classes under three possible management actions: scrub restoration (mechanical cutting followed by burning), a prescribed burn, or no intervention. A strategy prescribing the optimal management action for management units exhibiting different proportions of scrub-height classes was derived using dynamic programming. Scrub restoration was the optimal management action only in units dominated by mixed and tall scrub, and burning tended to be the optimal action for intermediate levels of short scrub. The optimal action was to do nothing when the amount of short scrub was greater than 30%, because short scrub mostly transitions to optimal height scrub (i.e., that state with the highest demographic success of scrub-jays) in the absence of intervention. Monte Carlo simulation of the optimal policy suggested that some form of management would be required every year. We note, however, that estimates of scrub-height transition probabilities were subject to several sources of uncertainty, and so we explored the management implications of alternative sets of transition probabilities. Generally, our analysis demonstrated the difficulty of managing for a species that requires midsuccessional habitat, and suggests that innovative management tools may be needed to help ensure the persistence of scrub-jays at Merritt Island National Wildlife Refuge. The development of a tailored monitoring program as a component of adaptive management could help reduce uncertainty about controlled and uncontrolled variation in transition probabilities of scrub-height and thus lead to improved decision making.

Control rod system useable for fuel handling in a gas-cooled nuclear reactor

DOEpatents

Spurrier, Francis R.

1976-11-30

A control rod and its associated drive are used to elevate a complete stack of fuel blocks to a position above the core of a gas-cooled nuclear reactor. A fuel-handling machine grasps the control rod and the drive is unlatched from the rod. The stack and rod are transferred out of the reactor, or to a new location in the reactor, by the fuel-handling machine.

Experimental investigations of stability of static liquid fillets and liquid-gas interface in capillary passages for gas-free liquid acquisition in zero gravity

NASA Astrophysics Data System (ADS)

Purohit, Ghanshyam Purshottamdas

Experimental investigations of static liquid fillets formed between small gaps of a cylindrical surface and a flat surface are carried out. The minimum volume of liquid required to form a stable fillet and the maximum liquid content the fillet can hold before becoming unstable are studied. Fillet shapes are captured in photographs obtained by a high speed image system. Experiments were conducted using water, UPA and PF 5060 on two surfaces-stand-blasted titanium and polished copper for different surface inclinations. Experimental data are generalized using appropriate non-dimensional groups. Analytical model are developed to describe the fillet curvature. Fillet curvature data are compared against model predictions and are found to be in close agreement. Bubble point experiments were carried out to measure the capillary pressure difference across the liquid-gas interface in the channels of photo-chemically etched disk stacks. Experiments were conducted using titanium stacks of five different geometrical configurations. Both well wetting liquids (IPA and PF5060) and partially wetting liquid (water) were used during experiments. Test results are found to be in close agreement with analytical predictions. Experiments were carried out to measure the frictional pressure drop across the stack as a function of liquid flow rate using two different liquids (water and IPA) and five stacks of different geometrical configurations. A channel pressure drop model is developed by treating the flow within stack channels as fully developed laminar flow between parallel plates and solving the one-dimensional Navier Stokes equation. An alternate model is developed by treating the flow in channels as flow within porous media. Expressions are developed for effective porosity and permeability for the stacks and the pressure drop is related to these parameters. Pressure drop test results are found to be in close agreement with model predictions. As a specific application of this work, a surface tension propellant management device (PMD) that uses photo-chemically etched disk stacks as capillary elements is examined. These PMDs are used in gas pressurized liquid propellant tanks to supply gas-free propellant to rocket engines in near zero-gravity environment. The experimentally validated models are integrated to perform key analyses for predicting PMD performance in zero gravity.

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, July--September 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

AQUATECH Systems, a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or lower sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 26 months in duration. During the 6 months of scheduled operations, between January and July of 1993, data was collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the absorber; Make-up reagent rates; Product quality including concentrations and compositions; System integration and control philosophy; and Membrane stability and performance with respect to foulants. The program is expected to be concluded in November 1993.« less

Partitioning coefficients of polycyclic aromatic hydrocarbons in stack gas from a municipal incinerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, W.M.G.; Chen, J.C.

1995-12-31

In this study, solid-gas partitioning coefficients of PAHs on fly ash in stack gas from a municipal incinerator were determined according to elution analysis with gas-solid chromatography. The fly ash from the electrostatic precipitator was sieved and packed into a 1/4 inch (6.3 mm) pyrex column. Elution analysis with gas-solid chromatography was conducted for three PAEs, Napthalene, Anthracene, and Pyrene. The temperature for elution analysis was in the range of 100{degrees}C to 300{degrees}C. Vg, specific retention volume obtained from elution analysis, and S, specific surface area of fly ash measured by a surface area measurement instrument were used to estimatemore » the solid-gas partitioning coefficient KR. In addition, the relationships between KR and temperature and KR and PAH concentrations were investigated.« less

Emissions of polycyclic aromatic hydrocarbons from batch hot mix asphalt plants.

PubMed

Lee, Wen-Jhy; Chao, Wen-Hui; Shih, Minliang; Tsai, Cheng-Hsien; Chen, Thomas Jeng-Ho; Tsai, Perng-Jy

2004-10-15

This study was set out to assess the characteristics of polycyclic aromatic hydrocarbon (PAH) emissions from batch hot mix asphalt (HMA) plants and PAH removal efficiencies associated with their installed air pollution control devices. Field samplings were conducted on six randomly selected batch HMA plants. For each selected plant, stack flue gas samples were collected from both stacks of the batch mixer (n = 5) and the preheating boiler (n = 5), respectively. PAH samples were also collected from the field to assess PAHs that were directly emitted from the discharging chute (n = 3). To assess PAH removal efficiencies of the installed air pollution control devices, PAH contents in both cyclone fly ash (n=3) and bag filter fly ash (n = 3) were analyzed. Results show that the total PAH concentration (mean; RSD) in the stack flue gas of the batch mixer (354 microg/Nm3; 78.5%) was higher than that emitted from the discharging chute (107 microg/Nm3; 70.1%) and that in the stack flue gas of the preheating boiler (83.7 microg/Nm3; 77.6%). But the total BaPeq concentration of that emitted from the discharging chute (0.950 microg/Nm3; 84.4%) was higher than contained in the stack flue gas of the batch mixer (0.629 microg/Nm3; 86.8%) and the stack flue gas of the preheating boiler (= 0.112 microg/Nm3; 80.3%). The mean total PAH emission factor for all selected batch mix plants (= 139 mg/ton x product) was much higher than that reported by U.S. EPA for the drum mix asphalt plant (range = 11.8-79.0 mg/ton x product). We found the overall removal efficiency of the installed air pollution control devices (i.e., cyclone + bag filter) on total PAHs and total BaPeq were 22.1% and 93.7%, respectively. This implies that the installed air pollution control devices, although they have a very limited effect on the removal of total PAHs, do significantly reduce the carcinogenic potencies associated with PAH emissions from batch HMA plants.

Performance of PEM fuel cells stack as affected by number of cell and gas flow-rate

NASA Astrophysics Data System (ADS)

Syampurwadi, A.; Onggo, H.; Indriyati; Yudianti, R.

2017-03-01

The proton exchange membrane fuel cell (PEMFC) is a promising technology as an alternative green energy due to its high power density, low operating temperatures, low local emissions, quiet operation and fast start up-shutdown. In order to apply fuel cell as portable power supply, the performance investigation of small number of cells is needed. In this study, PEMFC stacks consisting of 1, 3, 5 and 7-cells with an active area of 25 cm2 per cell have been designed and developed. Their was evaluated in variation of gas flow rate. The membrane electrode assembly (MEA) was prepared by hot-pressing commercial gas diffusion electrodes (Pt loading 0.5 mg/cm2) on pre-treated Nafion 117 membrane. The stacks were constructed using bipolar plates in serpentine pattern and Z-type gas flow configuration. The experimental results were presented as polarization and power output curves which show the effects of varying number of cells and H2/O2 flow-rates on the PEMFC performance. The experimental results showed that not only number of cells and gas flow-rates affected the fuel cells performance, but also the operating temperature as a result of electrochemistry reaction inside the cell.

A Hybrid Seismic Inversion Method for V P/V S Ratio and Its Application to Gas Identification

NASA Astrophysics Data System (ADS)

Guo, Qiang; Zhang, Hongbing; Han, Feilong; Xiao, Wei; Shang, Zuoping

2018-03-01

The ratio of compressional wave velocity to shear wave velocity (V P/V S ratio) has established itself as one of the most important parameters in identifying gas reservoirs. However, considering that seismic inversion process is highly non-linear and geological conditions encountered may be complex, a direct estimation of V P/V S ratio from pre-stack seismic data remains a challenging task. In this paper, we propose a hybrid seismic inversion method to estimate V P/V S ratio directly. In this method, post- and pre-stack inversions are combined in which the pre-stack inversion for V P/V S ratio is driven by the post-stack inversion results (i.e., V P and density). In particular, the V P/V S ratio is considered as a model parameter and is directly inverted from the pre-stack inversion based on the exact Zoeppritz equation. Moreover, anisotropic Markov random field is employed in order to regularise the inversion process as well as taking care of geological structures (boundaries) information. Aided by the proposed hybrid inversion strategy, the directional weighting coefficients incorporated in the anisotropic Markov random field neighbourhoods are quantitatively calculated by the anisotropic diffusion method. The synthetic test demonstrates the effectiveness of the proposed inversion method. In particular, given low quality of the pre-stack data and high heterogeneity of the target layers in the field data, the proposed inversion method reveals the detailed model of V P/V S ratio that can successfully identify the gas-bearing zones.

Impurity of Sulfur Layers and Magmatic Gas Scrubbing: Implications for Gas Monitoring

NASA Astrophysics Data System (ADS)

Scolamacchia, T.

2017-12-01

The evidence of bodies of elemental sulfur (Se) beneath acid crater lakes at the summit of composite active volcanoes has been recognized several decades ago (Oppenheimer and Stevenson, 1989; Christenson and Woods, 1993). But Se accumulation was already hypothesized a century ago at Kusatzu Shirane (Japan) based on the observation of sulfur spherules floating on its crater-lake (Ohashi, 1919). Since these pioneering works, other studies have focused on understanding key aspects of molten sulfur bodies, considered a feature unique of volcanic lakes. Instead, it is reasonable to assume that Se bodies occur in several volcanic settings because a) several reactions may lead to Se deposition from S-bearing gases, and b) crater-lakes, surface expressions of hydrothermal systems, are transient features. The scrubbing of several magmatic gases, some of which critical for volcano monitoring, has been attributed to ground/surface waters (Symonds et al. 2001). Nevertheless, gas scrubbing could reflect viscosity variations of impure Se within hydrothermal systems. Industrial experiments indicated that impurities (organics, H2S, ammonia, HCl, HF, HBr, HI) hinder Se polymerization at T ≥ 160ºC, allowing viscosity to remain low for long time depending on the maximum T achieved and heating rates (Bacon and Fanelli, 1943). However, a prolonged heating destroys the viscosity-modifying substances (e.g. H2Sx formed by reactions with organics, H2S, or ammonia) and dramatic Se viscosity increases occur after a certain number of heating and cooling cycles. A prolonged boiling of Se with organics was observed to release H2S, following H2Sx disruption. Some gases (e.g. SO2) do not affect Se viscosity. In volcanic environments gases such as SO2, CO2 could escape under Selow viscosity regimes. Also, halogens absence in gas emissions could be caused by their participation in reactions within S-layers causing its viscosity to remain low. More data are needed to validate the hypothesis stated above. References Bacon RF, Fanelli R, J Am Chem Soc 65, 639-648 (1943). Christenson BW, Wood CP, Bull Volcan 55, 547-565 (1993). Ohashi R, J. Akita Min. Coll 1, 1-10 (1919) Oppenheimer C, Stevenson D, Nature 342, 790-793 (1989) Symonds RB, Gerlach TM, Reed MH, J. Volc Geot Res 108, 303-341 (2001)

KSC-2009-3714

NASA Image and Video Library

2009-06-14

CAPE CANAVERAL, Fla. – Seen in the photo is the 7-inch quick disconnect that will be repaired on the hydrogen vent line to the Ground Umbilical Carrier Plate on space shuttle Endeavour's external fuel tank on Launch Pad 39A at NASA's Kennedy Space Center in Florida. Teams are removing the hardware to change out seals in the internal connection points. A leak of hydrogen at the location during tanking June 12 for the STS-127 mission caused the mission to be scrubbed at 12:26 a.m. June 13. The GUCP is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Endeavour is scheduled to launch on its STS-127 mission on June 17 at 5:40 a.m. EDT. Photo credit: NASA/Tim Jacobs

Development and implementation of a scrub habitat compensation plan for Kennedy Space Center

NASA Technical Reports Server (NTRS)

Schmalzer, Paul A.; Breininger, David R.; Adrian, Frederic W.; Schaub, Ron; Duncan, Brean W.

1994-01-01

Kennedy Space Center (KSC), located on Merritt Island on the east coast of central Florida, is one of three remaining major populations of the Florida Scrub Jay (Aphelocoma coerulescens coerulescens), listed as threatened by the U.S. Fish and Wildlife Service (USFWS) since 1987. Construction of new facilities by the National Aeronautics and Space Administration (NASA) on KSC over the next five years has the potential to impact up to 193 ac (78.1 ha) of Scrub Jay habitat. Under an early consultation process with the Endangered Species Office of the USFWS, NASA agreed to a compensation plan for loss of Scrub Jay habitat. The compensation plan required NASA to restore or create scrub on KSC at a 2:1 ratio for that lost. The compensation plan emphasized restoration of scrub habitat that is of marginal or declining suitability to Scrub Jays because it has remained unburned. Although prescribed burning has been conducted by the USFWS Merritt Island National Wildlife Refuge (MINWR) for more than ten years, significant areas of scrub remain unburned because they have been excluded from fire management units or because landscape fragmentation and a period of fire suppression allowed scrub to reach heights and diameters that are fire resistant. For such areas, mechanical cutting followed by prescribed burning was recommended for restoration. A second part of the restoration plan is an experimental study of scrub reestablishment (i.e., creation) on abandoned, well drained agricultural sites by planting scrub oaks and other scrub plants. The compensation plan identified 260 ac (105 ha) of scrub restoration in four areas and a 40 ac (16 ha) scrub creation site. Monitoring of restoration sites required under the plan included: establishing permanent vegetation sample transects before treatment and resampling annually for ten years after treatment, and color banding Scrub Jays to determine territories prior to treatment followed by monitoring reproductive success and survival for ten years after treatment. Monitoring scrub creation sites included determining survival of planted material for five years and establishing permanent transects to follow vegetation development for ten years after planting. Scrub Jay monitoring of creation sites is incorporated with that of adjacent restoration sites.

Process for injecting liquid in moving natural gas streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Budke, H.T. Jr.; Rivers, J.B. Jr.

1979-01-02

A simplified, low-cost method of treating pressurized, moving natural gas streams in order to control problems created by entrained water in the gas is provided which facilitates downstream treatment of the gas and increases product yields by lessening the formation of oil and water emulsions and hydrates which can coat and clog processing equipment, while also minimizing corrosion of the latter. The method involves introduction of an agent into the moving gas stream which includes a polymer having recurring quaternized pyridinium groups therein for controlling the emulsion, hydrate, and corrosion problems. The method is especially effective when the entrained watermore » contains surfactants, detergents, soaps, and the like. In preferred forms a low moleuclar weight copolymer of styrene and 2-vinyl pyridine dispersed in water is atomized into the gas stream adjacent cooling and scrubbing stations. 8 claims.« less

Process for injecting liquid in moving natural gas streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rivers, J.B. Jr.; Budke, H.T. Jr.

1979-01-02

Western Chemical Co.'s simplified, low-cost method of treating pressurized, moving natural gas streams in order to control problems created by entrained water facilitates the downstream treatment of the gas and increases product yields by lessening the formation of oil and water emulsions and hydrates that can coat and clog the processing equipment, while also minimizing equipment corrosion. The method involves introducing into the moving gas stream an agent that includes a polymer having recurring quaternized pyridinium groups for controlling the emulsion, hydrate, and corrosion problems. The method is especially effective when the entrained water contains surfactants, detergents, soaps, etc. Inmore » preferred forms, a low-molecular-weight copolymer of styrene and 2-vinyl pyridine dispersed in water is atomized into the gas stream adjacent to cooling and scrubbing stations. The method is particularly useful in connection with natural gas products plants.« less

An experimental approach aiming the production of a gas mixture composed of hydrogen and methane from biomass as natural gas substitute in industrial applications.

PubMed

Kraussler, Michael; Schindler, Philipp; Hofbauer, Hermann

2017-08-01

This work presents an experimental approach aiming the production of a gas mixture composed of H 2 and CH 4 , which should serve as natural gas substitute in industrial applications. Therefore, a lab-scale process chain employing a water gas shift unit, scrubbing units, and a pressure swing adsorption unit was operated with tar-rich product gas extracted from a commercial dual fluidized bed biomass steam gasification plant. A gas mixture with a volumetric fraction of about 80% H 2 and 19% CH 4 and with minor fractions of CO and CO 2 was produced by employing carbon molecular sieve as adsorbent. Moreover, the produced gas mixture had a lower heating value of about 15.5MJ·m -3 and a lower Wobbe index of about 43.4MJ·m -3 , which is similar to the typical Wobbe index of natural gas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Scrubbing liquors for nitrogen tetroxide

NASA Technical Reports Server (NTRS)

Thomas, J. J.

1978-01-01

Once it was determined that the wet scrubbing concept was the most practical solution to the N2O4 emission problem, it became important to optimize the composition of the scrubbing liquor. Several reagents were cited in the literature as being advantageous in scrubbing NO2. Experiments were conducted on a model wet scrubber in order to verify and rank the performances of these scrubbing liquors. The most efficient scrubbing liquor found experimentally was a 10% sodium sulfite solution.

Stacked Average Far-infrared Spectrum of Dusty Star-forming Galaxies from the Herschel/SPIRE Fourier Transform Spectrometer

NASA Astrophysics Data System (ADS)

Wilson, Derek; Cooray, Asantha; Nayyeri, Hooshang; Bonato, Matteo; Bradford, Charles M.; Clements, David L.; De Zotti, Gianfranco; Díaz-Santos, Tanio; Farrah, Duncan; Magdis, Georgios; Michałowski, Michał J.; Pearson, Chris; Rigopoulou, Dimitra; Valtchanov, Ivan; Wang, Lingyu; Wardlow, Julie

2017-10-01

We present stacked average far-infrared spectra of a sample of 197 dusty star-forming galaxies (DSFGs) at 0.005< z< 4 using about 90% of the Herschel Space Observatory SPIRE Fourier Transform Spectrometer (FTS) extragalactic data archive based on 3.5 years of science operations. These spectra explore an observed-frame 447-1568 GHz frequency range, allowing us to observe the main atomic and molecular lines emitted by gas in the interstellar medium. The sample is subdivided into redshift bins, and a subset of the bins are stacked by infrared luminosity as well. These stacked spectra are used to determine the average gas density and radiation field strength in the photodissociation regions (PDRs) of DSFGs. For the low-redshift sample, we present the average spectral line energy distributions of CO and H2O rotational transitions and consider PDR conditions based on observed [C I] 370 and 609 μm, and CO (7-6) lines. For the high-z (0.8< z< 4) sample, PDR models suggest a molecular gas distribution in the presence of a radiation field that is at least a factor of 103 larger than the Milky Way and with a neutral gas density of roughly {10}4.5-{10}5.5 cm-3. The corresponding PDR models for the low-z sample suggest a UV radiation field and gas density comparable to those at high-z. Given the challenges in obtaining adequate far-infrared observations, the stacked average spectra we present here will remain the measurements with the highest signal-to-noise ratio for at least a decade and a half until the launch of the next far-infrared facility. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Hardware simulation of fuel cell/gas turbine hybrids

NASA Astrophysics Data System (ADS)

Smith, Thomas Paul

Hybrid solid oxide fuel cell/gas turbine (SOFC/GT) systems offer high efficiency power generation, but face numerous integration and operability challenges. This dissertation addresses the application of hardware-in-the-loop simulation (HILS) to explore the performance of a solid oxide fuel cell stack and gas turbine when combined into a hybrid system. Specifically, this project entailed developing and demonstrating a methodology for coupling a numerical SOFC subsystem model with a gas turbine that has been modified with supplemental process flow and control paths to mimic a hybrid system. This HILS approach was implemented with the U.S. Department of Energy Hybrid Performance Project (HyPer) located at the National Energy Technology Laboratory. By utilizing HILS the facility provides a cost effective and capable platform for characterizing the response of hybrid systems to dynamic variations in operating conditions. HILS of a hybrid system was accomplished by first interfacing a numerical model with operating gas turbine hardware. The real-time SOFC stack model responds to operating turbine flow conditions in order to predict the level of thermal effluent from the SOFC stack. This simulated level of heating then dynamically sets the turbine's "firing" rate to reflect the stack output heat rate. Second, a high-speed computer system with data acquisition capabilities was integrated with the existing controls and sensors of the turbine facility. In the future, this will allow for the utilization of high-fidelity fuel cell models that infer cell performance parameters while still computing the simulation in real-time. Once the integration of the numeric and the hardware simulation components was completed, HILS experiments were conducted to evaluate hybrid system performance. The testing identified non-intuitive transient responses arising from the large thermal capacitance of the stack that are inherent to hybrid systems. Furthermore, the tests demonstrated the capabilities of HILS as a research tool for investigating the dynamic behavior of SOFC/GT hybrid power generation systems.

Epidemiologic characteristics of scrub typhus on Jeju Island.

PubMed

Lee, Sung Uk

2017-01-01

Scrub typhus is the most common febrile disease in Korea during the autumn. Jeju Island is the largest island in South Korea and has a distinctive oceanic climate. This study aimed to identify epidemiologic characteristics of scrub typhus on Jeju Island. From January 2011 to December 2016, 446 patients were diagnosed with scrub typhus on Jeju Island. The patients' personal data and the environmental factors that might be related to scrub typhus were investigated and retrospectively analyzed. The median age of the patients was 58-years-old (range, 8 to 91) and 43% of them worked in the agricultural, forestry or livestock industry. Regardless of their job, 87% of the patients had a history of either working outdoors or of other activities before developing scrub typhus. The south and southeast regions of Jeju Island, especially Namwon-eup, showed the highest incidence of scrub typhus. Workers in mandarin orange orchards seemed to be the highest risk group for scrub typhus infection. Scrub typhus on Jeju Island showed unique characteristics. To efficiently prevent scrub typhus, each year individual regional approaches should be developed based on the epidemiologic characteristics of the disease.

Integration of stripping of fines slurry in a coking and gasification process

DOEpatents

DeGeorge, Charles W.

1980-01-01

In an integrated fluid coking and gasification process wherein a stream of fluidized solids is passed from a fluidized bed coking zone to a second fluidized bed and wherein entrained solid fines are recovered by a wet scrubbing process and wherein the resulting solids-liquid slurry is stripped to remove acidic gases, the stripped vapors of the stripping zone are sent to the gas cleanup stage of the gasification product gas. The improved stripping integration is particularly useful in the combination coal liquefaction process, fluid coking of bottoms of the coal liquefaction zone and gasification of the product coke.

New design of a PEFC cathode separator of for water management

NASA Astrophysics Data System (ADS)

Sugiura, K.; Takahashi, N.; Kamimura, T.

2017-11-01

Generally, polymer electrolyte fuel cells (PEFCs) need humidifiers to prevent the drying of the membrane, but this use of humidifiers creates water management issues, such as the flooding/plugging phenomena and decreased system efficiency because of an increase in the electric energy needed for auxiliary equipment. Although most researchers have developed high-temperature membranes that do not need humidifiers, a lot of time is necessary for the development of these membranes, and these membranes drive up costs. Therefore, we propose a new cathode separator design that can recycle water generated by power generation in the same cell and a stack structure that can redistribute water collected in the cathode outlet manifold to drying cells. Because the new cathode separator has a bypass channel from the gas outlet to the gas inlet to transport excess water, a dry part in the gas inlet is supplied with excess water in the gas outlet through the bypass channel even if the PEFC is operated under dry conditions. Excess water in the PEFC stack can be transported from the cell with excess water to the drying cell through the cathode outlet manifold with a porous wall. Therefore, we confirm the influence of the plugging phenomenon in the cathode gas outlet manifold on the cell performance of each cell in the stack. As a result, the cell performance of the new cathode separator design is better than that of the standard separator under the low humidity conditions. We confirm that the plugging phenomenon in the cathode outlet manifold affects the cell performance of each cell in the stack.

Co-flow anode/cathode supply heat exchanger for a solid-oxide fuel cell assembly

DOEpatents

Haltiner, Jr., Karl J.; Kelly, Sean M.

2005-11-22

In a solid-oxide fuel cell assembly, a co-flow heat exchanger is provided in the flow paths of the reformate gas and the cathode air ahead of the fuel cell stack, the reformate gas being on one side of the exchanger and the cathode air being on the other. The reformate gas is at a substantially higher temperature than is desired in the stack, and the cathode gas is substantially cooler than desired. In the co-flow heat exchanger, the temperatures of the reformate and cathode streams converge to nearly the same temperature at the outlet of the exchanger. Preferably, the heat exchanger is formed within an integrated component manifold (ICM) for a solid-oxide fuel cell assembly.

Molten carbonate fuel cell

DOEpatents

Kaun, Thomas D.; Smith, James L.

1987-01-01

A molten electrolyte fuel cell with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas, the cell enclosures collectively providing an enclosure for the array and effectively avoiding the problems of electrolyte migration and the previous need for compression of stack components, the fuel cell further including an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

Molten carbonate fuel cell

DOEpatents

Kaun, T.D.; Smith, J.L.

1986-07-08

A molten electrolyte fuel cell is disclosed with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas. The cell enclosures collectively provide an enclosure for the array and effectively avoid the problems of electrolyte migration and the previous need for compression of stack components. The fuel cell further includes an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

Progress in the planar CPn SOFC system design verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elangovan, S.; Hartvigsen, J.; Khandkar, A.

1996-04-01

SOFCo is developing a high efficiency, modular and scaleable planar SOFC module termed the CPn design. This design has been verified in a 1.4 kW module test operated directly on pipeline natural gas. The design features multistage oxidation of fuel wherein the fuel is consumed incrementally over several stages. High efficiency is achieved by uniform current density distribution per stage, which lowers the stack resistance. Additional benefits include thermal regulation and compactness. Test results from stack modules operating in pipeline natural gas are presented.

At-Sea Test and Evaluation Of Oxygen (O2) Analyzers.

DTIC Science & Technology

1981-04-01

Paramagnetic Oxygen Analyzer 2-6 2.4 Thermomagnetic Oxygen Analyzer Sensor 2-8 2.5 Cell Voltage versus Oxygen Concentration at 2-11 Various Cell ...of flue gas out of the stack across the cell and back into the stack. In-situ units place the cell directly in the flue gas path in the uptake. ) The...repetitive failurc of a cell heater temperature control circuit and a control cabinet electron- ic malfunction. Of the five (5) units that remained in

Habitat model for the Florida Scrub Jay on John F. Kennedy Space Center

NASA Technical Reports Server (NTRS)

Breininger, David R.

1992-01-01

The Florida Scrub Jay is endemic to Florida. The John F. Kennedy Space Center (KSC) provides habitat for one of the three largest populations of the Florida Scrub Jay. This threatened bird occupies scrub, slash pine flatwoods, disturbed scrub, and coastal strand on KSC. Densities of Florida Scrub Jays were shown to vary with habitat characteristics but not necessarily with vegetation type. Relationships between Florida Scrub Jay densities and habitat characteristics were used to develop a habitat model to provide a tool to compare alternative sites for new facilities and to quantify environmental impacts. This model is being tested using long term demographic studies of colorbanded Florida Scrub Jays. Optimal habitat predicted by the model has greater than or equal to 50 percent of the shrub canopy comprised of scrub oaks, 20-50 percent open space or scrub oak vegetation within 100 m of a ruderal edge, less than or equal to 15 percent pine canopy cover, a shrub height of 120-170 cm, and is greater than or equal to 100 m from a forest. This document reviews life history, social behavior, food, foraging habitat, cover requirements, characteristics of habitat on KSC, and habitat preferences of the Florida Scrub Jay. Construction of the model and its limitations are discussed.

Preliminary design of a prototype particulate stack sampler. [For stack gas temperature under 300/sup 0/C

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

1978-06-01

A preliminary design of a prototype particulate stack sampler (PPSS) has been prepared, and development of several components is under way. The objective of this Environmental Protection Agency (EPA)-sponsored program is to develop and demonstrate a prototype sampler with capabilities similar to EPA Method 5 apparatus but without some of the more troublesome aspects. Features of the new design include higher sampling flow; display (on demand) of all variables and periodic calculation of percent isokinetic, sample volume, and stack velocity; automatic control of probe and filter heaters; stainless steel surfaces in contact with the sample stream; single-point particle size separationmore » in the probe nozzle; null-probe capability in the nozzle; and lower weight in the components of the sampling train. Design considerations will limit use of the PPSS to stack gas temperatures under approximately 300/sup 0/C, which will exclude sampling some high-temperature stacks such as incinerators. Although need for filter weighing has not been eliminated in the new design, introduction of a variable-slit virtual impactor nozzle may eliminate the need for mass analysis of particles washed from the probe. Component development has shown some promise for continuous humidity measurement by an in-line wet-bulb, dry-bulb psychrometer.« less

40 CFR 503.40 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR... sewage sludge incinerator stack is monitored continuously for carbon monoxide. (2) The monthly average concentration of carbon monoxide in the exit gas from a sewage sludge incinerator stack, corrected for zero...

Pressure Dome for High-Pressure Electrolyzer

NASA Technical Reports Server (NTRS)

Norman, Timothy; Schmitt, Edwin

2012-01-01

A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom segment and is trapped by the flange on the top dome segment when these components are bolted together with high-strength bolts. The pressure dome has several unique features. It is made (to ASME Pressure Vessel guidelines) in a high-strength aluminum alloy with the strength of stainless steel and the weight benefits of aluminum. The flange of the upper dome portion contains specially machined flats for mounting the dome, and other flats dedicated to the special feedthroughs for electrical connections. A pressure dome can be increased in length to house larger stacks (more cells) of the same diameter with the simple addition of a cylindrical segment. To aid in dome assembly, two stainless steel rings are employed. One is used beneath the heads of the high-strength bolts in lieu of individual hardened washers, and another is used instead of individual nuts. Like electrolyzers could be operated at low or high pressures simply by operating the electrolyzer outside or inside a pressurized dome.

Quantification of Induced Hypothermia from Aseptic Scrub Applications during Rodent Surgery Preparation

PubMed Central

Skorupski, Anna M; Zhang, Jingyi; Ferguson, Danielle; Lawrence, Frank

2017-01-01

Laboratory mice (Mus musculus) are prone to develop hypothermia during anesthesia for surgery, thus potentially impeding anesthetic recovery, wound healing, and future health. The core body temperatures of isoflurane-anesthetized mice are influenced by the choice of supplemental heat sources; however, the contribution of various surgical scrubs on the body temperatures of mice under gas anesthesia has not been assessed. We sought to quantify the effect of using alcohol (70% isopropyl alcohol [IPA]) compared with saline to rinse away surgical scrub on the progression of hypothermia in anesthetized mice (n = 47). IPA, room-temperature saline, or warmed saline (37 °C) was combined with povidone–iodine and then assessed for effects on core (rectal) and surface (infrared) temperatures. Agents were applied to a 2×2-cm shaved abdominal area of mice maintained on a water-recirculating blanket (at 38 °C) under isoflurane anesthesia (1.5% to 2.0% at 0.6 L/min) for 30 min. Although all scrub regimens significantly decreased body temperature at the time of application, treatments that included povidone–iodine led to the coldest core temperatures, which persisted while mice were anesthetized. Compared with room-temperature saline and when combined with povidone–iodine, warming of saline did not ameliorate heat loss. IPA alone demonstrated the most dramatic cooling of both surface and core readings at application but generated an unanticipated warming (rebound) phase during which body temperatures equilibrated with those of controls within minutes of application. Although alcohol is inappropriate as a stand-alone agent for surgical skin preparation, IPA is a viable alternative to saline-based rinses in this context, and its use should be encouraged within institutional guidance for rodent surgical procedures without concern for prolonged hypothermia in mice. PMID:28903829

Development and Applications of a Stage Stacking Procedure

NASA Technical Reports Server (NTRS)

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

2012-01-01

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

eRHIC Beam Scrubbing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, S. Y.

We propose using beam scrubbing to mitigate the electron cloud effect in the eRHIC. The bunch number is adjusted below the heat load limit, then it increases with the reduced secondary electron yield resulted from the beam scrubbing, up to the design bunch number. Since the electron density threshold of beam instability is lower at the injection, a preliminary injection scrubbing should go first, where large chromaticity can be used to keep the beam in the ring for scrubbing. After that, the beam can be ramped to full energy, allowing physics scrubbing. Simulations demonstrated that with beam scrubbing in amore » reasonable period of time, the eRHIC baseline design is feasible.« less

One hospital's clinical evaluation of brushless scrubbing.

PubMed

Berman, Mara

2004-02-01

BRUSHLESS SCRUBBING rapidly is becoming an accepted method for surgical hand scrubbing. AN EVALUATION was undertaken at an acute care hospital in the southeastern United States to examine brushless scrubbing before laminectomy, craniotomy, and colectomy procedures. PATIENTS DID NOT SHOW an increase in postoperative surgical site infections when the brushless scrubbing product was used. SATISFACTION AND COMPLIANCE among users of the product was positive.

Epidemiologic characteristics of scrub typhus on Jeju Island

PubMed Central

2017-01-01

OBJECTIVES Scrub typhus is the most common febrile disease in Korea during the autumn. Jeju Island is the largest island in South Korea and has a distinctive oceanic climate. This study aimed to identify epidemiologic characteristics of scrub typhus on Jeju Island. METHODS From January 2011 to December 2016, 446 patients were diagnosed with scrub typhus on Jeju Island. The patients’ personal data and the environmental factors that might be related to scrub typhus were investigated and retrospectively analyzed. RESULTS The median age of the patients was 58-years-old (range, 8 to 91) and 43% of them worked in the agricultural, forestry or livestock industry. Regardless of their job, 87% of the patients had a history of either working outdoors or of other activities before developing scrub typhus. The south and southeast regions of Jeju Island, especially Namwon-eup, showed the highest incidence of scrub typhus. Workers in mandarin orange orchards seemed to be the highest risk group for scrub typhus infection. CONCLUSIONS Scrub typhus on Jeju Island showed unique characteristics. To efficiently prevent scrub typhus, each year individual regional approaches should be developed based on the epidemiologic characteristics of the disease. PMID:28823118

Endangered and Threatened Species at Kennedy Space Center Merritt Island National Wildlife Refuge

NASA Technical Reports Server (NTRS)

Galdolfi, Catherine

2010-01-01

Throughout my internship, I assisted with the long-term monitoring of the Florida Scrub- Jay (Aphelocoma coerulescens), a threatened species endemic to Florida. The Florida Scrub Jay diet consists of insects and small vertebrates throughout most of the year; however, during the winter their primary diet is acorns because the insect population is low. Furthermore, the Florida Scrub-Jay is a habitat specialist that lives in a disappearing plant community called the scrub, which consists of sand live oak, myrtle oak and chapman oak. The Florida Scrub-Jay is considered threatened because its numbers are decreasing primarily due to the loss of habitat that it needs to survive. Scrub habitat is highly desirable for human development because it is high, dry, and sandy. Periodic controlled burns maintain the scrub in a low, open condition favored by Scrub-Jays. Florida Scrub-Jays build their nests approximately 3-5 feet (approximately 1.5 m) above the ground in shrubby oaks (Breininger 153), mate for life and are cooperative breeders; which means that the young jays remain in their natal territory for at least a year to help their parents defend their territory, feed the young, and mob predators. (Breininger 152). I assisted in conducting monthly censuses at long-term monitoring sites and a juvenile in July survey to determine reproductive success for the year. In addition, to Scrub-Jay monitoring, I also had the opportunity to assist with some long term monitoring of ecosystem recovery. Scrub is a fire maintained system. Fire maintains the structure of scrub necessary for many of the threatened species that reside in the scrub habitat.

Associated factors and clinical implications of serum aminotransferase elevation in scrub typhus.

PubMed

Su, Tung-Hung; Liu, Chun-Jen; Shu, Pei-Yun; Fu, Yang-Hsien; Chang, Chi-Hsien; Jao, Ping; Kao, Jia-Horng

2016-12-01

Timely diagnosis and prompt treatment can reduce the complications of scrub typhus. It is thus important to find easy laboratory tests to help in the diagnosis, especially in patients without eschar at initial presentation. Because serum aminotransferase elevation is common in scrub typhus, its associated factors and clinical implications need further investigations. We conducted a retrospective study in Kinmen, Taiwan, to collect clinically suspected scrub typhus patients notified to Taiwan Centers for Disease Control for confirmation during 2005-2010. Scrub typhus was diagnosed and Orientia tsutsugamushi was genotyped by serological or molecular assays. The laboratory data and clinical information were recorded for analysis. Overall, 344 suspected scrub typhus patients were reported to Taiwan Centers for Disease Control and 288 of them were certified scrub typhus. Scrub typhus patients had significantly more thrombocytopenia, serum aminotransferase elevation (76% vs. 54%, p = 0.001), higher frequency of fever, eschar, and lymphadenopathy, compared with nontyphus patients. Hepatic dysfunction in scrub typhus was associated with older age, longer fever duration, and absence of lymphadenopathy, but seemed to be unrelated to the rickettsial genotypes. Multivariate analysis showed that serum aminotransferase elevation (odds ratio: 3.75; p = 0.003; 95% confidence interval: 1.56-9.01) independently predicted scrub typhus. Furthermore, in suspected scrub typhus patients without eschar, 92% of true typhus patients had serum aminotransferase elevation compared with the nontyphus ones (odds ratio: 6.47; p = 0.028, 95% confidence interval: 1.23-34.11). Hepatic dysfunction in scrub typhus patients is associated with older age, longer fever duration, and absence of lymphadenopathy. Serum aminotransferase elevation can aid in the diagnosis of scrub typhus, especially in suspected patients without eschar. Copyright © 2014. Published by Elsevier B.V.

Hemorrhagic Transformation of Scrub Typhus Encephalitis: A Rare Entity.

PubMed

Kim, H-C; Yoon, K-W; Yoo, D-S; Cho, C-S

2015-12-01

Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.

Climate variability, animal reservoir and transmission of scrub typhus in Southern China

PubMed Central

Li, Xiaoning; Ma, Yu; Tao, Xia; Wu, Xinwei

2017-01-01

Objectives We aimed to evaluate the relationships between climate variability, animal reservoirs and scrub typhus incidence in Southern China. Methods We obtained data on scrub typhus cases in Guangzhou every month from 2006 to 2014 from the Chinese communicable disease network. Time-series Poisson regression models and distributed lag nonlinear models (DLNM) were used to evaluate the relationship between risk factors and scrub typhus. Results Wavelet analysis found the incidence of scrub typhus cycled with a period of approximately 8–12 months and long-term trends with a period of approximately 24–36 months. The DLNM model shows that relative humidity, rainfall, DTR, MEI and rodent density were associated with the incidence of scrub typhus. Conclusions Our findings suggest that the incidence scrub typhus has two main temporal cycles. Determining the reason for this trend and how it can be used for disease control and prevention requires additional research. The transmission of scrub typhus is highly dependent on climate factors and rodent density, both of which should be considered in prevention and control strategies for scrub typhus. PMID:28273079

Climate variability, animal reservoir and transmission of scrub typhus in Southern China.

PubMed

Wei, Yuehong; Huang, Yong; Li, Xiaoning; Ma, Yu; Tao, Xia; Wu, Xinwei; Yang, Zhicong

2017-03-01

We aimed to evaluate the relationships between climate variability, animal reservoirs and scrub typhus incidence in Southern China. We obtained data on scrub typhus cases in Guangzhou every month from 2006 to 2014 from the Chinese communicable disease network. Time-series Poisson regression models and distributed lag nonlinear models (DLNM) were used to evaluate the relationship between risk factors and scrub typhus. Wavelet analysis found the incidence of scrub typhus cycled with a period of approximately 8-12 months and long-term trends with a period of approximately 24-36 months. The DLNM model shows that relative humidity, rainfall, DTR, MEI and rodent density were associated with the incidence of scrub typhus. Our findings suggest that the incidence scrub typhus has two main temporal cycles. Determining the reason for this trend and how it can be used for disease control and prevention requires additional research. The transmission of scrub typhus is highly dependent on climate factors and rodent density, both of which should be considered in prevention and control strategies for scrub typhus.

Small stack performance of intermediate temperature-operating solid oxide fuel cells using stainless steel interconnects and anode-supported single cell

NASA Astrophysics Data System (ADS)

Bae, Joongmyeon; Lim, Sungkwang; Jee, Hyunjin; Kim, Jung Hyun; Yoo, Young-Sung; Lee, Taehee

We are developing 1 kW class solid oxide fuel cell (SOFC) system for residential power generation (RPG) application supported by Korean Government. Anode-supported single cells with thin electrolyte layer of YSZ (yttria-stabilized zirconia) or ScSZ (scandia-stabilized zirconia) for intermediate temperature operation (650-750 °C), respectively, were fabricated and small stacks were built and evaluated. The LSCF/ScSZ/Ni-YSZ single cell showed performance of 543 mW cm -2 at 650 °C and 1680 mW cm -2 at 750 °C. The voltage of 15-cell stack based on 5 cm × 5 cm single cell (LSM/YSZ/Ni-YSZ) at 150 mW was 12.5 V in hydrogen as fuel of 120 sccm per cell at 750 °C and decreased to about 10.9 V at 500 h operation time. A 5-cell stack based on the LSCF/YSZ/FL/Ni-YSZ showed the maximum power density of 30 W, 25 W and 20 W at 750 °C, 700 °C and 650 °C, respectively. LSCF/ScSZ/Ni-YSZ-based stack showed better performance than LSCF/YSZ/Ni-YSZ stack from the experiment temperature range. I- V characteristics by using hydrogen gas and reformate gas of methane as fuel were investigated at 750 °C in LSCF/ScSZ/FL/Ni-YSZ-based 5-cell stack.

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

PubMed

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

2012-08-21

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

Is it time for brushless scrubbing with an alcohol-based agent?

PubMed

Gruendemann, B J; Bjerke, N B

2001-12-01

The practice of surgical scrubbing in perioperative settings is changing rapidly. This article presents information about eliminating the traditional scrub brush technique and using an alcohol formulation for surgical hand scrubs. Also covered are antimicrobial agents, relevant US Food and Drug Administration classifications, skin and fingernail care, and implementation of changes. The article challenges surgical team members to evaluate a new and different approach to surgical hand scrubbing.

Plant communities of Santa Rosa Island, Channel Islands National Park

USGS Publications Warehouse

Clark, Ronilee A.; Halvorson, William L.; Sawdo, Andell A.; Danielsen, Karen C.

1990-01-01

A survey of the plant communities on Santa Rosa Island, Channel Islands National Park, was conducted from January through July 1988.  Vegetation data were collected at 296 sites using a releve technique.  The plant communities described include: grassland, coastal marsh, caliche scrub, coastal sage scrub, lupine scrub, baccharis scrub, coastal bluff scrub, coastal dune scrub, mixed chaparral, mixed woodland, torrey pine woodland, closed-cone pine woodland, island oak woodland, riparian woodland, and riparian herbaceous vegetation. The areal extent of each community was mapper on USGS 7.5' topographic maps, and digitized for GIS manipulation.

KSC-2009-1911

NASA Image and Video Library

2009-02-27

CAPE CANAVERAL, Fla. – Close-up of a Florida scrub jay in the woods near NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky

KSC-2009-1909

NASA Image and Video Library

2009-02-27

CAPE CANAVERAL, Fla. – Florida scrub jays scan their territory from a bush at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky

KSC-2009-1910

NASA Image and Video Library

2009-02-27

CAPE CANAVERAL, Fla. – Florida scrub jays scan their territory from a bush at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky

KSC-2009-1908

NASA Image and Video Library

2009-02-27

CAPE CANAVERAL, Fla. – A Florida scrub jay perches on a branch in a wooded area at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky

[Parameters optimization and cleaning efficiency evaluation of attrition scrubbing remediation of Pb-contaminated soil].

PubMed

Yang, Wen; Huang, Jin-lou; Peng, Hui-qing; Li, Si-tuo

2013-09-01

Attrition scrubbing was used to remediate lead contaminated-site soil, and the main purpose was to remove fine particles and lead contaminants from the surface of sand. The optimal parameters of attrition scrubbing were determined by orthogonal experiment, and three soil samples with different lead concentration were subjected to attrition scrubbing experiments. The results showed that the optimal scrubbing parameters were: a solid ratio of 70% dry matter, a temperature of 25 degrees C, an attrition time of 30 min, and an attrition speed of 1200 r x min(-1). Before attrition scrubbing, the screening and analysis of soil showed that in all three soil samples, lead was mainly enriched on sand and fine particles, and the distribution of lead was highly correlated to the organic matter. After attrition scrubbing, the washing efficiency of the original state lead contaminated sand soil in triplicates was 67.61%, 31.71% and 41.01%, respectively, which indicates that attrition scrubbing can remove part of the fine soil and lead contaminants from the surface of sand, to accomplish the purpose of pollutants enrichment. Scanning electron microscopy (SEM) analysis showed that the sand surface became smooth after attrition scrubbing. The results above show that attrition scrubbing has a good washing effect for the remediation of lead contaminated sand soil.

Assessing the effectiveness of scrub management at the landscape scale using rapid field assessment and remote sensing.

PubMed

Redhead, John; Cuevas-Gonzales, Maria; Smith, Geoffrey; Gerard, France; Pywell, Richard

2012-04-30

Controlling scrub encroachment is a major challenge for conservation management on chalk grasslands. However, direct comparisons of scrub removal methods have seldom been investigated, particularly at the landscape scale. Effective monitoring of grassland scrub is problematic as it requires simultaneous information on large scale patterns in scrub cover and fine-scale changes in the grassland community. This study addressed this by combining analysis of aerial imagery with rapid field surveys in order to compare the effectiveness of four scrub management strategies on Defence Training Estate Salisbury Plain, UK. Study plots were sited within areas undergoing management and in unmanaged controls. Controls showed dramatic increases in scrub cover, with encroachment of a mean 1096 m(2) per hectare over ten years. Whilst all management strategies were effective in reducing scrub encroachment, they differed in their ability to influence regeneration of scrub and grassland quality. There was a general trend, evident in both the floral community and scrub levels, of increased effectiveness with increasing management intensity. The dual methodology proved highly effective, allowing rapid collection of data over a range of variables and spatial scales unavailable to each method individually. The methodology thus demonstrates potential for a useful monitoring tool. Copyright © 2011 Elsevier Ltd. All rights reserved.

Development and evaluation of a new alcohol-based surgical hand scrub formulation with persistent antimicrobial characteristics and brushless application.

PubMed

Hobson, D W; Woller, W; Anderson, L; Guthery, E

1998-10-01

Since the introduction in the 1970s of surgical hand scrub formulations that contain 4% chlorhexidine gluconate (CHG), new surgical scrub formulations that have improved efficacy, persistence, or significantly improved use characteristics have not been forthcoming. In addition, the manufacturer's labeling for popular hand scrub products generally requires scrub times in excess of 6 minutes, whereas current practical needs call for products with substantially shorter scrub times. A new alcohol-based surgical scrub formulation, which has ingredients that provide emollient, surfactant, and antimicrobial persistence characteristics to complement the rapid and broad-spectrum antiseptic qualities of alcohol, has been developed in an effort to address these current practical needs. The relative efficacy of a new alcohol-based surgical scrub formulation that contains ingredients that provide surfactant and antimicrobial persistence characteristics was compared with that of commercial 4% CHG and 7.5% povidone iodine (PVPI) formulations with use of human subjects. Hand antimicrobial count sampling was performed by using standardized "glove juice" methodology. The efficacy and persistence results of the new formulation showed statistically significant improvement over both CHG and PVPI at a substantially lessened scrub time (3 minutes). In addition, use of the new formulation without a scrub brush produced results statistically similar to 3-minute applications with either a brush or a sponge. The new alcohol-based formulation demonstrates promise as a new surgical hand scrub formulation with antimicrobial and use characteristics that are significantly improved over current CHG and PVPI formulations. These studies demonstrate the suitability of this formulation for use as a surgical hand scrub and for brushless application.

Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014

PubMed Central

Hu, Wen-Biao; Haque, Ubydul; Weppelmann, Thomas A.; Wang, Yong; Liu, Yun-Xi; Li, Xin-Lou; Sun, Hai-Long; Sun, Yan-Song; Clements, Archie C. A.; Li, Shen-Long; Zhang, Wen-Yi

2016-01-01

Background Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized. Objective This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease. Method Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted. Results During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation. Conclusions The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country. PMID:27479297

Scrub typhus

PubMed Central

Rapsang, Amy G; Bhattacharyya, Prithwis

2013-01-01

Scrub typhus is an acute febrile illness caused by orientia tsutsugamushi, transmitted to humans by the bite of the larva of trombiculid mites. It causes a disseminated vasculitic and perivascular inflammatory lesions resulting in significant vascular leakage and end-organ injury. It affects people of all ages and even though scrub typhus in pregnancy is uncommon, it is associated with increased foetal loss, preterm delivery, and small for gestational age infants. After an incubation period of 6-21 days, onset is characterized by fever, headache, myalgia, cough, and gastrointestinal symptoms. A primary papular lesion which later crusts to form a flat black eschar, may be present. If untreated, serious complications may occur involving various organs. Laboratory studies usually reveal leukopenia, thrombocytopenia, deranged hepatic and renal function, proteinuria and reticulonodular infiltrate. Owing to the potential for severe complications, diagnosis, and decision to initiate treatment should be based on clinical suspicion and confirmed by serologic tests. A therapeutic trial of tetracycline or chloramphenicol is indicated in patients in whom the diagnosis of scrub typhus is suspected. The recommended treatment regimen for scrub typhus is doxycycline. Alternative regimens include tetracycline, chloramphenicol, azithromycin, ciprofloxacin, rifampicin, and roxithromycin. Treatment of pregnant women with azithromycin was successfully done without relapse and with favorable pregnancy outcomes. Hence, early diagnosis and treatment are essential in order to reduce the mortality and the complications associated with the disease. We searched the English-language literature for reports of scrub typhus in children, pregnant women, and non-pregnant patients with scrub typhus, using the MEDLINE/PubMed database, which includes citations from 1945 to the present time. We used the search terms ‘scrub typhus’, ‘scrub typhus’ and ‘pregnancy’, ‘scrub typhus’ and ‘children’, ‘scrub typhus’ and ‘complications’, ‘scrub typhus’ and ‘treatment’. PMID:23825810

Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014.

PubMed

Wu, Yi-Cheng; Qian, Quan; Soares Magalhaes, Ricardo J; Han, Zhi-Hai; Hu, Wen-Biao; Haque, Ubydul; Weppelmann, Thomas A; Wang, Yong; Liu, Yun-Xi; Li, Xin-Lou; Sun, Hai-Long; Sun, Yan-Song; Clements, Archie C A; Li, Shen-Long; Zhang, Wen-Yi

2016-08-01

Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized. This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease. Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted. During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation. The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country.

Modification of the ECAS reference steam power generating plant to comply with the EPA 1979 new source performance standards

NASA Technical Reports Server (NTRS)

Fogelson, S. A.; Chait, I. L.; Bradley, W. J.; Benson, W.

1980-01-01

Detailed capital cost estimates for the ECAS and modified reference plants in mid-1978 dollars for both 250 and 175 F (394 and 353 K) stack gas reheat temperatures based on the cost estimates developed for the ECAS study are presented. The scope of the work included technical assessment of sulfur dioxide scrubber system design, on site calcination versus purchased lime, reheat of stack gas, effect of sulfur dioxide scrubber on particulate emission, and control of nitrogen oxides.

Testing of a Shrouded, Short Mixing Stack Gas Eductor Model Using High Temperature Primary Flow.

DTIC Science & Technology

1982-10-01

problem but of less significance than the heated surfaces of shipboard structure. Various types of electronic equipments and sensors carried by a combatant...here was to validate current procedures by comparison with previous data it was not considered essential to rein- stall these sensors or duplicate...sec) 205 tABLE XIX Mixing Stack Temperatura Data, Model B Thermocouple Axial Mixing Stack Temperature _ mbjr Posii--- .. (I IF) . Uptake 180 850 950

The lived experiences of operating theatre scrub nurses learning technical scrub skills 'I'm doing this right, aren't I? Am I doing this right?'

PubMed

Radford, Eleanor J; Fotis, Theo

2018-01-01

Operating theatre scrub nurses (OTSNs) are not required to have undertaken a secondary or specialist post-registration theatre qualification to work in the operating theatre (OT) setting in the UK. From the systematic review there is only very limited literature or research in how technical scrub skills are acquired. This study explores the lived experiences of OTSNs learning technical scrub skills. The study employed the qualitative methodology of interpretative phenomenological analysis. Data was collected from six participating OTSNs using semi-structured interviews. Four superordinate themes emerged: How technical scrub skills are established, Gatekeepers, How the learner feels whilst learning and, Reflections of the experienced scrub nurse. The study found that the experiences of OTSNs learning technical scrub skills are varied and a variety of teaching and learning methods are utilised. These experiences were influenced by the team, mentor and surgeon within the OT environment. Lived experiences were also influenced by organisational structure and service pressures within the NHS.

The Effects of Surgical Hand Scrubbing Protocols on Skin Integrity and Surgical Site Infection Rates: A Systematic Review.

PubMed

Liu, Liang Qin; Mehigan, Sinead

2016-05-01

This systematic review aimed to critically appraise and synthesize updated evidence regarding the effect of surgical-scrub techniques on skin integrity and the incidence of surgical site infections. Databases searched include the Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Embase, and Cochrane Central. Our review was limited to eight peer-reviewed, randomized controlled trials and two nonrandomized controlled trials published in English from 1990 to 2015. Comparison models included traditional hand scrubbing with chlorhexidine gluconate or povidone-iodine against alcohol-based hand rubbing, scrubbing with a brush versus without a brush, and detergent-based antiseptics alone versus antiseptics incorporating alcohol solutions. Evidence showed that hand rubbing techniques are as effective as traditional scrubbing and seem to be better tolerated. Hand rubbing appears to cause less skin damage than traditional scrub protocols, and scrub personnel tolerated brushless techniques better than scrubbing using a brush. Copyright © 2016 AORN, Inc. Published by Elsevier Inc. All rights reserved.

40 CFR 98.173 - Calculating GHG emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b... basis (% CO2). Q = Hourly stack gas volumetric flow rate (scfh). %H2O = Hourly moisture percentage in... vented through the same stack as any combustion unit or process equipment that reports CO2 emissions...

40 CFR 98.173 - Calculating GHG emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b..., dry basis (% CO2). Q = Hourly stack gas volumetric flow rate (scfh). %H2O = Hourly moisture percentage... reduction furnace are vented through the same stack as any combustion unit or process equipment that reports...

40 CFR 98.173 - Calculating GHG emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b... basis (% CO2). Q = Hourly stack gas volumetric flow rate (scfh). %H2O = Hourly moisture percentage in... vented through the same stack as any combustion unit or process equipment that reports CO2 emissions...

Remote control flare stack igniter for combustible gases

NASA Technical Reports Server (NTRS)

Ray, W. L.

1972-01-01

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

40 CFR 63.11466 - What are the performance test requirements for new and existing sources?

Code of Federal Regulations, 2010 CFR

2010-07-01

... (Appendix A-1) to select sampling port locations and the number of traverse points in each stack or duct... of the stack gas. (iii) Method 3, 3A, or 3B (Appendix A-2) to determine the dry molecular weight of...

RADIATION STABILITY OF ORGANIC LIQUIDS. Semi-Annual Report No. 4 for July 1 to December 31, 1958

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, R.M.; Towle, L.H.

1959-01-01

0 @ 4 2 7 1 8 3 7 1 7 6 TBP from 0 to 100 were irradiated with electrons to 300 to 400 whr/liter. The G(total acid) values obtained indicated that, from 0 to 60 wt, % TBP, the acid produc tion rate is proportional to wt, % TBP; above 60 wt, % TBP the acid production rate is lower. Normalized total acid G values, obtained by partition of the dose on a basis of wt, % TBP, ranged from 2.31 to 3.52. Seven TBP-Amsco solutions, ranging from 5 to 60 wt. % TBP, and samples of puremore » TBP and pure dibutyl phenylphosphorate (DBPP) were irradiated to 400 whr/liter, Five compositions of TBP, DBPP, Amsco, and tetralin were irradiated to 200 whr/liter. The amount of radiationinduced unsataration was measured for each of the above samples. The data indicated that unsaturation varied inversely with wt. % TBP. The DBPP exerted a small protective effect, as did tetralin, in reducing radiation damage to the Amsco. Diethyl carbonate, irradiated to 392 whr/liter, had a G(gas) value of 4.86, a--G (target destruction) value of 5.50, and a --G /sub M/(polymer) value of 2.80. Diethyl carbonate, after irradiation, extracts U better than virgin material and strips equally as well. The irradiated diethyl carbonate exhibited no difference from virgin material in emulsification tendency. Dibutyl phenylphosphorate-Amsco systems, at dose levels of either 200 or 400 whr/liter, showed that acid production is about proportioral to wt. % DBPP. Studies of DBPP-Amsco-tetralin systems at 200 whr/ liter indicated that tetralin is more acceptable than decalin for enhancing the solubility of the DBPP-uranium complex in Amsco, thus suppressing third-phase phenomena. Tetralin also reduced acid production from DBPP under irradiation. Tributyl phosphate, dibutyl phosphoric acid, and di-(2- ethylhexyl) phosphoric acid were irradiated in the pure state to 300 whr/liter. The G(gas) values were 1.9, 3.3, and 3.1, respectively, and the G(total acid) values were 2.3, 2.1, and 1.2. The--G values for target converted to polymer were 0.22 for the DBP, and 0.32 for the D2EHP. Tri-n-octyl phosphine oxide was irradiated in the pure state to 400 whr/liter. The G(gas) value of 1.82 was comparable to a value of 1.45 found previously at 2040 whr/1iter. Values of --G/ sub M/ for target and polymer were approximately double the values previously found at 2040 whr/ liter. Amines, including tri-lauryl amine, n-benzyl heptadecyl amine, tri-iso-octyl amine, Primene JM-T, and tri-oetyl-decyl-t-amine (Alamine) were irradiated to either 200- or 400-whr/liter doses. The Primene produced the lowest --G (polymer) value, (1.50) and the Alamine produced the highest -- G/sub M/(total target destroyed) value (3.49). An Alamine-tridecanol- Amsconitric acid system yielded the lowest G(gas) value (1.89) while the corresponding tri-lauryl amine system produced the highest (3.12). The most extensive emulsification occurred with the 0.5M tri-lauryl amtne-Amscotridecanol system while the n-benzyl heptadecyl amine system exhtbited the lowest emulsification tendency, The most efficient U extractant system observed was the Alamine-Amsco-tridecanol-nitric acid composition, at the 0.5M-Alamine level. A comparison was made of the quantity and composition of material removed from irradiated TBP-Amsco by various scrubbing media. A single scrub with 2M NaOH appears four times more efftcient than does a single scrub with satarated CaOH in removing acidic radiolysis products. The emulsification tendency of the scrubbed organic appears to increase with the quantity of acidic radiolysis products removed. Radiolysis products other than those of acidic natare (polymer) are apparently not removed by the scrubbing media investigated in this study. An ir« less

Acute Cholecystitis in Patients with Scrub Typhus.

PubMed

Lee, Hyun; Ji, Misuk; Hwang, Jeong-Hwan; Lee, Ja-Yeon; Lee, Ju-Hyung; Chung, Kyung Min; Lee, Chang-Seop

2015-11-01

Acute cholecystitis is a rare complication of scrub typhus. Although a few such cases have been reported in patients with scrub typhus, the clinical course is not well described. Of 12 patients, acute cholecystitis developed in 66.7% (8/12) of patients older than 60 yr. The scrub typhus group with acute cholecystitis had marginal significant longer hospital stay and higher cost than the group without cholecystitis according to propensity score matching. Scrub typhus should be kept in mind as a rare etiology of acute cholecystitis in endemic areas because the typical signs of scrub typhus such as skin rash and eschar can present after the abdominal pain.

Scrub Typhus Outbreak in a Remote Primary School, Bhutan, 2014.

PubMed

Tshokey, Tshokey; Graves, Stephen; Tshering, Dorji; Phuntsho, Kelzang; Tshering, Karchung; Stenos, John

2017-08-01

Scrub typhus in Bhutan was first reported in 2009. We investigated an outbreak of scrub typhus in a remote primary school during August-October 2014. Delay in recognition and treatment resulted in 2 deaths from meningoencephalitis. Scrub typhus warrants urgent public health interventions in Bhutan.

Gas block mechanism for water removal in fuel cells

DOEpatents

Issacci, Farrokh; Rehg, Timothy J.

2004-02-03

The present invention is directed to apparatus and method for cathode-side disposal of water in an electrochemical fuel cell. There is a cathode plate. Within a surface of the plate is a flow field comprised of interdigitated channels. During operation of the fuel cell, cathode gas flows by convection through a gas diffusion layer above the flow field. Positioned at points adjacent to the flow field are one or more porous gas block mediums that have pores sized such that water is sipped off to the outside of the flow field by capillary flow and cathode gas is blocked from flowing through the medium. On the other surface of the plate is a channel in fluid communication with each porous gas block mediums. The method for water disposal in a fuel cell comprises installing the cathode plate assemblies at the cathode sides of the stack of fuel cells and manifolding the single water channel of each of the cathode plate assemblies to the coolant flow that feeds coolant plates in the stack.

Method for monitoring stack gases for uranium activity

DOEpatents

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

1985-07-03

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

Method for monitoring stack gases for uranium activity

DOEpatents

Beverly, Claude R.; Ernstberger, Harold G.

1988-01-01

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

Acute pancreatitis associated with scrub typhus.

PubMed

Sv, Padmavathi Devi; M, Aruna; Kumar, Anil Cv; Krishna Reddy, Hari; Bl, Sangeetha; Siva Kumar, V

2017-01-01

Scrub typhus, or tsutsugamushi fever, is a zoonosis of rural Asia and the western Pacific islands. The causative organism, Orientia (formerly Rickettsia) tsutsugamushi, is transmitted to humans by the bite of a larval Leptotrombidium mite (chigger). Scrub typhus may have gastrointestinal presentations, such as acute acalculous cholecystitis, duodenal ulcer perforation, peritonitis and gastric ulceration. Acute pancreatitis with scrub typhus has been reported rarely. We report a patient of scrub typhus complicated by acute pancreatitis and acute kidney injury. © The Author(s) 2016.

Evaluation of toxic and genotoxic potential of a wet gas scrubber effluent obtained from wooden-based biomass furnaces: A case study in the red ceramic industry in southern Brazil.

PubMed

Bortolotto, Tiago; da Silva, Jaqueline; Sant'Ana, Alex Célio; Tomazi, Kamila Osowski; Geremias, Reginaldo; Angioletto, Elídio; Pich, Claus Tröger

2017-09-01

Red ceramic industry in southern Brazil commonly uses wood biomass as furnace fuel generating great amounts of gas emissions and ash. To avoid their impact on atmospheric environment, wet scrubbing is currently being applied in several plants. However, the water leachate formed could be potentially toxic and not managed as a common water-based effluent, since the resulting wastewater could carry many toxic compounds derived from wood pyrolysis. There is a lack of studies regarding this kind of effluent obtained specifically and strictly from wooden-based biomass furnaces. Therefore, we conducted an evaluation of toxic and genotoxic potentials of this particular type of wet gas scrubber effluent. Physical-chemical analysis showed high contents of several contaminants, including phenols, sulphates and ammoniacal nitrogen, as well as the total and suspended solids. The effluent cause significant toxicity towards microcrustacean Artemia sp. (LC 50 = 34.4%) and Daphnia magna (Toxicity Factor = 6 on average) and to higher plants (Lactuca sativa L. and Allium cepa L.) with acute and sub-acute effects in several parameters. Besides, using plasmid DNA, significant damage was observed in concentrations 12.5% and higher. In cellular DNA, concentrations starting from 12.5% and 6.25% showed significant increase in Damage Index (DI) and Damage Frequency (DF), respectively. The results altogether suggest that the effluent components, such phenols, produced by wood combustion can be volatilized, water scrubbed, resulting in a toxic and genotoxic effluent which could contaminate the environment. Copyright © 2017 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gottesfeld, S.

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

Develop and test fuel cell powered on-site integrated total energy system

NASA Technical Reports Server (NTRS)

Kaufman, A.; Feigenbaum, H.; Wang, C. L.; Werth, J.; Whelan, J. A.

1983-01-01

Test results are presented for a 24 cell, two sq ft (4kW) stack. This stack is a precursor to a 25kW stack that is a key milestone. Results are discussed in terms of cell performance, electrolyte management, thermal management, and reactant gas manifolding. The results obtained in preliminary testing of a 50kW methanol processing subsystem are discussed. Subcontracting activities involving application analysis for fuel cell on site integrated energy systems are updated.

The Case for Natural Gas Fueled Solid Oxide Fuel Cell Power Systems for Distributed Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chick, Lawrence A.; Weimar, Mark R.; Whyatt, Greg A.

2015-02-01

Natural-gas-fueled solid oxide fuel cell (NGSOFC) power systems yield electrical conversion efficiencies exceeding 60% and may become a viable alternative for distributed generation (DG) if stack life and manufacturing economies of scale can be realized. Currently, stacks last approximately 2 years and few systems are produced each year because of the relatively high cost of electricity from the systems. If mass manufacturing (10,000 units per year) and a stack life of 15 years can be reached, the cost of electricity from an NGSOFC system is estimated to be about 7.7 ¢/kWh, well within the price of commercial and residential retailmore » prices at the national level (9.9-10¢/kWh and 11-12 ¢/kWh, respectively). With an additional 5 ¢/kWh in estimated additional benefits from DG, NGSOFC could be well positioned to replace the forecasted 59-77 gigawatts of capacity loss resulting from coal plant closures due to stricter emissions regulations and low natural gas prices.« less

Effect of surgical hand scrub time on subsequent bacterial growth.

PubMed

Wheelock, S M; Lookinland, S

1997-06-01

In this experimental study, the researchers evaluated the effect of surgical hand scrub time on subsequent bacterial growth and assessed the effectiveness of the glove juice technique in a clinical setting. In a randomized crossover design, 25 perioperative staff members scrubbed for two or three minutes in the first trial and vice versa in the second trial, after which the wore sterile surgical gloves for one hour under clinical conditions. The researchers then sampled the subjects' nondominant hands for bacterial growth, cultured aliquots from the sampling solution, and counted microorganisms. Scrubbing for three minutes produced lower mean log bacterial counts than scrubbing for two minutes. Although the mean bacterial count differed significantly (P = .02) between the two-minute and three-minute surgical hand scrub times, it fell below 0.5 log, which is the threshold for practical and clinical significance. This finding suggests that a two-minute surgical hand scrub is clinically as effective as a three-minute surgical had scrub. The glove juice technique demonstrated sensitivity and reliability in enumerating bacteria on the hands of perioperative staff members in a clinical setting.

Acoustic streaming related to minor loss phenomenon in differentially heated elements of thermoacoustic devices

NASA Astrophysics Data System (ADS)

Mironov, Mikhail; Gusev, Vitalyi; Auregan, Yves; Lotton, Pierrick; Bruneau, Michel; Piatakov, Pavel

2002-08-01

It is demonstrated that the differentially heated stack, the heart of all thermoacoustic devices, provides a source of streaming additional to those associated with Reynolds stresses in quasi-unidirectional gas flow. This source of streaming is related to temperature-induced asymmetry in the generation of vortices and turbulence near the stack ends. The asymmetry of the hydrodynamic effects in an otherwise geometrically symmetric stack is due to the temperature difference between stack ends. The proposed mechanism of streaming excitation in annular thermoacoustic devices operates even in the absence of thermo-viscous interaction of sound waves with resonator walls. copyright 2002 Acoustical Society of America.

40 CFR 98.173 - Calculating GHG emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b... basis (% CO2). Q = Hourly stack gas volumetric flow rate (scfh). %H2O = Hourly moisture percentage in... furnace are vented through the same stack as any combustion unit or process equipment that reports CO2...

Stacking Oxygen-Separation Cells

NASA Technical Reports Server (NTRS)

Schroeder, James E.

1991-01-01

Simplified configuration and procedure developed for assembly of stacks of solid-electrolyte cells separating oxygen from air electrochemically. Reduces number of components and thus reduces probability of such failures as gas leaks, breakdown of sensitive parts, and electrical open or short circuits. Previous, more complicated version of cell described in "Improved Zirconia Oxygen-Separation Cell" (NPO-16161).

40 CFR Table I-17 to Subpart I of... - Expected and Possible By-Products for Electronics Manufacturinglg

Code of Federal Regulations, 2014 CFR

2014-07-01

... Electronics Manufacturinglg I Table I-17 to Subpart I of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics... for Electronics Manufacturinglg For each stack system for which you use the “stack test method” to...

40 CFR Table I-12 to Subpart I of... - Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Use With the Stack Test Method (300 mm and 450 mm Wafers) I Table I-12 to Subpart I of Part 98... (Bijk) for Semiconductor Manufacturing for Use With the Stack Test Method (300 mm and 450 mm Wafers...

40 CFR Table I-11 to Subpart I of... - Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Use With the Stack Test Method (150 mm and 200 mm Wafers) I Table I-11 to Subpart I of Part 98... (Bijk) for Semiconductor Manufacturing for Use With the Stack Test Method (150 mm and 200 mm Wafers...

Scrub typhus: Clinical spectrum and outcome.

PubMed

Venkategowda, Pradeep M; Rao, S Manimala; Mutkule, Dnyaneshwar P; Rao, Mallela V; Taggu, Alai N

2015-04-01

Scrub typhus is one of the differential diagnoses for fever with thrombocytopenia. ARDS associated with Scrub typhus has high morbidity and mortality. To evaluate clinical features, lab values, and outcome in patients with scrub typhus and comparison in patients with or without ARDS. A prospective observational study was conducted on 109 patients with febrile illness and thrombocytopenia during a period of 12 months. All 109 patients were tested with both Immune-chromatography test and Weil felix test. Patients having either Immune-chromatography test/Weil felix test positive have been included and considered as scrub typhus positive whereas negative for both Immune-chromatography and Weil felix test were excluded. Clinical features, lab parameters, and outcome were evaluated in all patients with scrub typhus. Statistical analysis used in this study was T-test. Among 58 patients who were included (After exclusion of 51 patients among total of 109 patients) 34 patients had no ARDS and 24 patients had ARDS. The clinical feature like dyspnoea, cough, low blood pressure (MAP<65 mmHg), IVC collapsibility (by ultrasound) and laboratory parameters like decreased Hemoglobin, Hematocrit, Serum albumin, and increased serum creatinine, serum total bilirubin, SGOT, SGPT, LDH, CPK, and serum lactate were statistically significant (P < 0.0001) in scrub typhus patients group with ARDS. The higher titers of Weil-felix can be correlated with more severe form of disease according to our observation. All 34 Scrub typhus patients without ARDS recovered completely. Among 24 Scrub typhus patients with ARDS, 22 patients recovered, and 2 patients died. Scrub typhus is an important differential diagnosis in a patients having fever with thrombocytopenia. Scrub typhus associated with ARDS has high morbidity and mortality. Early diagnosis and treatment with doxycycline can prevent the occurrence of ARDS.

A Pilot-Scale Evaluation of a New Technology to Control NO(x) Emissions from Boilers at KSC: Hydrogen Peroxide Injection into Boiler Flue Gases Followed by Wet Scrubbing of Acid Gases

NASA Technical Reports Server (NTRS)

Cooper, C. David

1997-01-01

Emissions of nitrogen oxides NO(x) are a significant problem in the United States. NO(x) are formed in any combustion process, therefore it is not surprising that NO(x) are emitted from the boilers at KSC. Research at UCF has shown (in the laboratory) that injecting H2O2 into hot simulated flue gases can oxidize the NO and NO2 to their acid gas forms, HNO2 and HNO3, respectively. These acid gases are much more water soluble than their counterparts, and theoretically can be removed easily by wet scrubbing. This technology was of interest to NASA, both for their boilers at KSC, and for their combustion sources elsewhere. However, it was necessary to field test the technology and to provide pilot-scale data to aid in design of full-scale facilities. Hence this project was initiated in May of 1996.

Meteorological factors and risk of scrub typhus in Guangzhou, southern China, 2006–2012

PubMed Central

2014-01-01

Background Scrub typhus is becoming the most common vector born disease in Guangzhou, southern China. In this study, we aimed to examine the effect of weather patterns on the incidence of Scrub typhus in the subtropical city of Guangzhou for the period 2006–2012, and assist public health prevention and control measures. Methods Scrub typhus reported cases during the period of 2006–2012 in Guangzhou were obtained from National Notifiable Disease Report System (NNDRS). Simultaneous meteorological data including temperature, relative humidity, atmospheric pressure, sunshine, and rainfall were obtained from the documentation of the Guangzhou Meteorological Bureau. A negative binomial regression was used to identify the relationship between meteorological variables and scrub typhus. Results Annual incidence rates of scrub typhus from 2006 to 2012 were 3.25, 2.67, 3.81, 4.22, 4.41, 5.12, and 9.75 (per 100 000) respectively. Each 1°C rise in temperature corresponded to an increase of 14.98% (95% CI 13.65% to 16.33%) in the monthly number of scrub typhus cases, while a 1 hPa rise in atmospheric pressure corresponded to a decrease in the number of cases by 8.03% (95% CI −8.75% to −7.31%). Similarly, a 1 hour rise in sunshine corresponded to an increase of 0.17% or 0.54%, and a 1 millimeter rise in rainfall corresponded to an increase of 0.05% or 0.10%, in the monthly number of scrub typhus cases, depending on the variables considered in the model. Conclusion Our study provided evidence that climatic factors were associated with occurrence of scrub typhus in Guangzhou city, China. Temperature, duration of sunshine, and rainfall were positively associated with scrub typhus incidence, while atmospheric pressure was inversely associated with scrub typhus incidence. These findings should be considered in the prediction of future patterns of scrub typhus transmission. PMID:24620733

Gas pollutants removal in a single- and two-stage ejector-venturi scrubber.

PubMed

Gamisans, Xavier; Sarrà, Montserrrat; Lafuente, F Javier

2002-03-29

The absorption of SO(2) and NH(3) from the flue gas into NaOH and H(2)SO(4) solutions, respectively has been studied using an industrial scale ejector-venturi scrubber. A statistical methodology is presented to characterise the performance of the scrubber by varying several factors such as gas pollutant concentration, air flowrate and absorbing solution flowrate. Some types of venturi tube constructions were assessed, including the use of a two-stage venturi tube. The results showed a strong influence of the liquid scrubbing flowrate on pollutant removal efficiency. The initial pollutant concentration and the gas flowrate had a slight influence. The use of a two-stage venturi tube considerably improved the absorption efficiency, although it increased energy consumption. The results of this study will be applicable to the optimal design of venturi-based absorbers for gaseous pollution control or chemical reactors.

Wind Tunnel Model Study of the Hot Exhaust Plume from the Compressor Research Facility at Wright-Patterson Air Force Base, Ohio

DTIC Science & Technology

1977-10-01

PLUME FROM THE COMPRESSOR JtESEARCHJAC ILITY AT WRIGHT- /ATTERSON AIR FORCE JBASE, OHIO , r= mrm (.) Gary R./Ludwig 9. PERFORMING ORGANIZATION NAME... ms Mass flux of stack exhaust gas (slugs/sec) nrtfl Mass flux of ambient air and stack exhaust gas mixture st plume cross-section A (slugs/sec...the horizontal momentum flux in the ambient wind be the same in the model as it is in full-scale. /»» Ms M i a. ’ ro P>"S P*» + ’f (3) where 0

Generator stator core vent duct spacer posts

DOEpatents

Griffith, John Wesley; Tong, Wei

2003-06-24

Generator stator cores are constructed by stacking many layers of magnetic laminations. Ventilation ducts may be inserted between these layers by inserting spacers into the core stack. The ventilation ducts allow for the passage of cooling gas through the core during operation. The spacers or spacer posts are positioned between groups of the magnetic laminations to define the ventilation ducts. The spacer posts are secured with longitudinal axes thereof substantially parallel to the core axis. With this structure, core tightness can be assured while maximizing ventilation duct cross section for gas flow and minimizing magnetic loss in the spacers.

Severe Fever with Thrombocytopenia Syndrome in Patients Suspected of Having Scrub Typhus.

PubMed

Wi, Yu Mi; Woo, Hye In; Park, Dahee; Lee, Keun Hwa; Kang, Cheol-In; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon

2016-11-01

To determine prevalence of severe fever with thrombocytopenia syndrome in South Korea, we examined serum samples from patients with fever and insect bite history in scrub typhus-endemic areas. During the 2013 scrub typhus season, prevalence of this syndrome among patients suspected of having scrub typhus was high (23.0%), suggesting possible co-infection.

Neuropsychiatric Manifestations of Scrub Typhus.

PubMed

Mahajan, Sanjay K; Mahajan, Sanyam K

2017-01-01

Scrub typhus is caused by Orientia tsutsugamushi characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system. It was thought to have been eradicated from India. Recently it is being reported from many areas of India. The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are not uncommon but are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillan-Barré syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhus is limited to case reports mainly. This article reviews various neurological manifestations of scrub typhus reported in literature.

Neuropsychiatric Manifestations of Scrub Typhus

PubMed Central

Mahajan, Sanjay K.; Mahajan, Sanyam K.

2017-01-01

Scrub typhus is caused by Orientia tsutsugamushi characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system. It was thought to have been eradicated from India. Recently it is being reported from many areas of India. The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are not uncommon but are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillan-Barré syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhus is limited to case reports mainly. This article reviews various neurological manifestations of scrub typhus reported in literature. PMID:28694624

A theoretical/experimental program to develop active optical pollution sensors: Quantitative remote Raman lidar measurements of pollutants from stationary sources

NASA Technical Reports Server (NTRS)

Poultney, S. K.; Brumfield, M. L.; Siviter, J. S.

1975-01-01

Typical pollutant gas concentrations at the stack exits of stationary sources can be estimated to be about 500 ppm under the present emission standards. Raman lidar has a number of advantages which makes it a valuable tool for remote measurements of these stack emissions. Tests of the Langley Research Center Raman lidar at a calibration tank indicate that night measurements of SO2 concentrations and stack opacity are possible. Accuracies of 10 percent are shown to be achievable from a distance of 300 m within 30 min integration times for 500 ppm SO2 at the stack exits. All possible interferences were examined quantitatively (except for the fluorescence of aerosols in actual stack emissions) and found to have negligible effect on the measurements. An early test at an instrumented stack is strongly recommended.

Nitrogen dioxide absorption in aqueous sodium sulfite

NASA Astrophysics Data System (ADS)

Shen, Chen Hua

The Clean Air Act of 1990 requires additional reduction of acid gases, sulfur dioxide, and nitrogen oxides released into the atmosphere from coal-fired electric power plants. In the case of older existing power plants, a possible retrofit strategy is to oxidize nitric oxide (NO, the major constituent of NOsbX in flue gas) to nitrogen dioxide (NOsb2) by the addition of methanol or other hydrocarbons into the duct at an optimum temperature regime. NOsb2 can then be removed by either modifying existing SOsb2 control equipment or by adding a limestone (CaCOsb3) slurry scrubbing process. Limestone reacts with SOsb2 to from CaSOsb3, and the free sulfite (SO{sb3sp{=}}) in the solution is reactive toward NOsb2. The focus of this research is to study the reaction between NOsb2 and aqueous sulfite at elevated temperature and in the presence of gas phase Osb2. The removal of NOsb2 by limestone slurry scrubbing involves the reaction between NOsb2 and SO{sb3sp{=}}, bisulfite (HSO{sb3sp{-}}) and water. The reactions between NOsb2 and SO{sb3sp{=}}/HSO{sb3sp{-}} are first order in both reactants, while the NOsb2-water reaction is second order in NOsb2 concentration. The rate constants of the above reactions and the NOsb2-thiosulfate (Ssb2O{sb3sp{=}}) reaction were determined at 55sp°C. SO{sb3sp{=}} was found to be the most reactive toward NOsb2, while the contribution of chemical reaction still dominated in the absorption of NOsb2 into water. The effect of gas phase SOsb2 and Osb2, and liquid phase additives such as Ssb2O{sb3sp{=}}, Casp{++}, Mgsp{++}, and Clsp{-} on NOsb2 absorption was also investigated. The absorption of NOsb2 catalyzes free radical reactions that lead to sulfite oxidation. A semi-empirical model was proposed to relate the rate of sulfite oxidation to the rate of NOsb2 absorption. Thiosulfate inhibits sulfite oxidation by providing an alternative route for the termination of the free radical reactions, and a fundamental model was derived to quantify the effect of Ssb2O{sb3sp{=}} on sulfite oxidation. The absorption of NOsb2 into aqueous bisulfide (HSsp{-}) was studied in an attempt to discover alternative scrubbing technologies. The reaction between NOsb2 and HSsp{-} is twice as fast as the NOsb2-SO{sb3sp{=}} reaction at 55sp°C. A semi-empirical model was proposed to relate NOsb2 absorption to HSsp{-} oxidation. This study has shown that acceptable level of NOsb2 removal by a conventional limestone slurry scrubber is not probable. However, aqueous scrubbing of NOsb2 by Nasb2SOsb3 and Nasb2S solutions are viable options. Furthermore, significant reduction in hold tank liquid depth and/or oxidizing air stoichiometry is possible by NOsb2 injection.

Anode protection system for shutdown of solid oxide fuel cell system

DOEpatents

Li, Bob X; Grieves, Malcolm J; Kelly, Sean M

2014-12-30

An Anode Protection Systems for a SOFC system, having a Reductant Supply and safety subsystem, a SOFC anode protection subsystem, and a Post Combustion and slip stream control subsystem. The Reductant Supply and safety subsystem includes means for generating a reducing gas or vapor to prevent re-oxidation of the Ni in the anode layer during the course of shut down of the SOFC stack. The underlying ammonia or hydrogen based material used to generate a reducing gas or vapor to prevent the re-oxidation of the Ni can be in either a solid or liquid stored inside a portable container. The SOFC anode protection subsystem provides an internal pressure of 0.2 to 10 kPa to prevent air from entering into the SOFC system. The Post Combustion and slip stream control subsystem provides a catalyst converter configured to treat any residual reducing gas in the slip stream gas exiting from SOFC stack.

Determination of Fluorine in Fluoro-Organic Compounds in Low Concentrations in Air

DTIC Science & Technology

1944-06-27

Analysis of 2-Fluoroethanol in Air ..... SUMMARY BIBLIOGRAPHY 15 APPENDIX , 16 FIGURE 1 Apparatus PLATE 1 CDS Scrubber SECRET ) SECRET...liter, and 68$ at 1 - 2 mg. per liter. By using two scrubbers in series, 90$ of di-isopropyl fluorophosphate was recovered at a concentration of 1 to 2...chromic acid and detection of HP by etching of the glass container ; (5) scrub- bing the gas with ammonia and decomposing the fluoro-organic compound4

Industrial chimney monitoring - contemporary methods

NASA Astrophysics Data System (ADS)

Kaszowska, Olga; Gruchlik, Piotr; Mika, Wiesław

2018-04-01

The paper presents knowledge acquired during the monitoring of a flue-gas stack, performed as part of technical and scientific surveillance of mining activity and its impact on industrial objects. The chimney is located in an area impacted by mining activity since the 1970s, from a coal mine which is no longer in existence. In the period of 2013-16, this area was subject to mining carried out by a mining entrepreneur who currently holds a license to excavate hard coal. Periodic measurements of the deflection of the 113-meter chimney are performed using conventional geodetic methods. The GIG used 3 methods to observe the stack: landbased 3D laser scanning, continuous deflection monitoring with a laser sensor, and drone-based visual inspections. The drone offered the possibility to closely inspect the upper sections of the flue-gas stack, which are difficult to see from the ground level.

SOLVENT EXTRACTION PROCESS

DOEpatents

Jonke, A.A.

1957-10-01

In improved solvent extraction process is described for the extraction of metal values from highly dilute aqueous solutions. The process comprises contacting an aqueous solution with an organic substantially water-immiscible solvent, whereby metal values are taken up by a solvent extract phase; scrubbing the solvent extract phase with an aqueous scrubbing solution; separating an aqueous solution from the scrubbed solvent extract phase; and contacting the scrubbed solvent phase with an aqueous medium whereby the extracted metal values are removed from the solvent phase and taken up by said medium to form a strip solution containing said metal values, the aqueous scrubbing solution being a mixture of strip solution and an aqueous solution which contains mineral acids anions and is free of the metal values. The process is particularly effective for purifying uranium, where one starts with impure aqueous uranyl nitrate, extracts with tributyl phosphate dissolved in carbon tetrachloride, scrubs with aqueous nitric acid and employs water to strip the uranium from the scrubbed organic phase.

Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea.

PubMed

Kwak, Jaewon; Kim, Soojun; Kim, Gilho; Singh, Vijay P; Hong, Seungjin; Kim, Hung Soo

2015-06-29

Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN) model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered.

Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea

PubMed Central

Kwak, Jaewon; Kim, Soojun; Kim, Gilho; Singh, Vijay P.; Hong, Seungjin; Kim, Hung Soo

2015-01-01

Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN) model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered. PMID:26132479

Multiple eschars in scrub typhus: a case report.

PubMed

Koraluru, Munegowda; Nandigam, Manideep; Bairy, Indira; Vidyasagar, Sudha; Varma, Muralidhar

2017-01-01

Eschar in scrub typhus aids in early diagnosis and institution of appropriate therapy; however, the eschar positivity rates vary greatly in endemic regions. Multiple eschars in scrub typhus are a rare presentation. Our patient presented with fever and multiple eschars and was empirically started on doxycycline. Nested polymerase chain reaction from all the four eschars and from EDTA blood were positive for 56-kDa type-specific antigen which is specific for Orientia tsutsugamushi The patient recovered completely after 7 days of antibiotic treatment. He was from an area where scrub typhus was not observed previously. An eschar in an acute febrile patient from the "tsutsugamushi triangle" is a valuable sign in scrub typhus diagnosis. A search for multiple eschars in scrub typhus must be made by clinicians. © The Author(s) 2016.

A SCREENING LEVEL RISK ASSESSMENT OF THE INDIRECT IMPACTS FROM THE COLUMBUS WASTE TO ENERGY FACILITY IN COLUMBUS, OHIO

EPA Science Inventory

Testing for emissions of dioxins from the stack of the Columbus, Ohio Waste to Energy (WTE) municipal solid waste combustion facility in 1992 implied that dioxin concentrations in stack gas averaged 328 ng TEQ/m3. The incinerator had been in operation since the early 1980s. In ...

40 CFR Table I-9 to Subpart I of... - Methods and Procedures for Conducting Emissions Test for Stack Systems

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Methods and Procedures for Conducting Emissions Test for Stack Systems I Table I-9 to Subpart I of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics...

Conversion of ammonia into hydrogen and nitrogen by reaction with a sulfided catalyst

DOEpatents

Matthews, Charles W.

1977-01-01

A method is provided for removing ammonia from the sour water stream of a coal gasification process. The basic steps comprise stripping the ammonia from the sour water; heating the stripped ammonia to a temperature from between 400.degree. to 1,000.degree. F; passing the gaseous ammonia through a reactor containing a sulfided catalyst to produce elemental hydrogen and nitrogen; and scrubbing the reaction product to obtain an ammonia-free gas. The residual equilibrium ammonia produced by the reactor is recycled into the stripper. The ammonia-free gas may be advantageously treated in a Claus process to recover elemental sulfur. Iron sulfide or cobalt molybdenum sulfide catalysts are used.

Sludge incineration in single stage combustor with gas scrubbing followed by afterburning and heat recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albertson, O.E.; Baturay, A.

1990-04-17

This patent describes the method for disposal of waste organic sludge of the type which contains at least one certain waste material that is either a low melting eutectic that softens or heavy metal that fumes at the highest temperature required to effect incineration of the sludge and cleansing by burning of the resultant gases. It comprises: the steps of combusting the sludge in a single combustion mass overlain by a gas-filled freeboard thereby to effect burning of substantially the entire content of combustible solids while yielding wet gases which contain entrained particulates as well as combustible and non-combustible constituents,more » volatiles and condensible matter.« less

Successfully Managed Acute Transverse Myelitis Related to Scrub Typhus and Serial Image Findings

PubMed Central

Yun, Jae Sung; Song, Ji Soo; Choi, Eun Jung; Hwang, Jeong-Hwan; Lee, Chang-Seop; Park, Eun Hae

2017-01-01

Central nervous system involvement manifesting as meningitis or meningoencephalitis is a known complication of scrub typhus, but very few spinal cord lesions such as acute transverse myelitis (ATM) have been reported in association with this disease. Scrub typhus patients with a spinal lesion present with neurologic symptoms including dysuria, motor, and sensory weakness. Herein, we describe a rare case of ATM associated with scrub typhus. Clinical characteristics, cerebrospinal fluid cytology, Orientia tsutsugamushi serum antibody titer, and serial magnetic resonance imaging scans resulted in a diagnosis of ATM associated with scrub typhus. PMID:28115665

Successfully Managed Acute Transverse Myelitis Related to Scrub Typhus and Serial Image Findings.

PubMed

Yun, Jae Sung; Song, Ji Soo; Choi, Eun Jung; Hwang, Jeong-Hwan; Lee, Chang-Seop; Park, Eun Hae

2017-03-01

AbstractCentral nervous system involvement manifesting as meningitis or meningoencephalitis is a known complication of scrub typhus, but very few spinal cord lesions such as acute transverse myelitis (ATM) have been reported in association with this disease. Scrub typhus patients with a spinal lesion present with neurologic symptoms including dysuria, motor, and sensory weakness. Herein, we describe a rare case of ATM associated with scrub typhus. Clinical characteristics, cerebrospinal fluid cytology, Orientia tsutsugamushi serum antibody titer, and serial magnetic resonance imaging scans resulted in a diagnosis of ATM associated with scrub typhus.

40 CFR Table 2 to Subpart Cccc of... - Requirements for Performance Tests

Code of Federal Regulations, 2010 CFR

2010-07-01

... port's location and the number of traverse points Method 1* 3. Measure volumetric flow rate. Method 2* 4. Perform gas analysis to determine the dry molecular weight of the stack gas Method 3* 5...

Differential diagnosis of scrub typhus meningitis from tuberculous meningitis using clinical and laboratory features.

PubMed

Valappil, Ashraf V; Thiruvoth, Sohanlal; Peedikayil, Jabir M; Raghunath, Praveenkumar; Thekkedath, Manojan

2017-12-01

The involvement of the central nervous system in the form of meningitis or meningoencephalitis is common in scrub typhus and is an important differential diagnosis of other lymphocytic meningitis like tuberculous meningitis (TBM). The aim of this study was to identify the clinical and laboratory parameters that may be helpful in differentiating scrub typhus meningitis from TBM. We compared of the clinical and laboratory features of 57 patients admitted with scrub typhus meningitis or TBM during a 3-year period. Patients who had abnormal cerebrospinal fluid (CSF) and positive scrub typhus enzyme-linked immunosorbent assay serology (n=28) were included in the scrub typhus meningitis group, while the TBM group included those who satisfied the consensus diagnostic criteria of TBM (n=29). Compared with the TBM group, the mean duration of symptoms was less in patients with scrub typhus meningitis, who also had a lower magnitude of neurological deficits, such as altered mental status and cranial nerve and motor deficits. Patients with scrub typhus meningitis had a lower CSF white blood-cell count (WBC) than the TBM group (130.8±213 195±175 cells/mm 3 , P=0.002), lower CSF protein elevation (125±120 vs. 195.2±108.2mg/dl, P=0.002), and higher CSF sugar (70.1±32.4 vs. 48.7±23.4mg/dl, P=0.006). Features predictive of the diagnosis of scrub typhus meningitis included the absence of neurological impairment at presentation, blood serum glutamic-oxaloacetic transaminase>40 international units (IU)/L, serum glutamic-pyruvic transaminase>60 IU/L, total blood leukocyte count>10,000/mm 3 , CSF protein<100mg/dl, CSF sugar>50mg/dl, CSF WBC<100 cells/mm 3 . All patients with scrub typhus meningitis recovered completely following doxycycline therapy CONCLUSIONS: This study suggests that, clinical features, including duration of fever, neurological deficits at presentation and laboratory parameters such as CSF pleocytosis,CSF protein elevation, CSF sugar levels and liver enzyme values are helpful in differentiating scrub typhus meningitis from tuberculous meningits. These features with scrub IgM serology may be helpful in identifying patients with scrub meningitis and in avoiding prolonged empirical antituberculous therapy in cases of lymphocytic meningitis. Copyright © 2017 Elsevier B.V. All rights reserved.

A method for the measurement of atmospheric HONO based on DNPH derivatization and HPLC analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, X.; Qiao, H.; Deng, G.

1999-10-15

A simple measurement technique was developed for atmospheric HONO based on aqueous scrubbing using a coil sampler followed by 2,4-dinitrophenylhydrazine (DNPH) derivatization and high-performance liquid chromatographic (HPLC) analysis. Quantitative sampling efficiency was obtained using a 1 mM phosphate buffer, pH 7.0, as the scrubbing solution at a gas sampling flow rate of 2 L min{sup {minus}1} and a liquid flow rate of 0.24 mL min{sup {minus}1}. Derivation of the scrubbed nitrous acid by DNPH was fast and was completed within 5 min in a derivatization medium containing 300 {micro}M DNPH and 8 mM HCI at 45 C. The azide derivativemore » was separated from DNPH reagent and carbonyl derivatives by reverse-phase HPLC and was detected with an UV detector at 309 nm. The detection limit is {le}5 pptv and may be lowered to 1 pptv with further DNPH purification. Interferences from NO, NO{sub 2} PAN, O{sub 3}, HNO{sub 3}, and HCHO were studied and found to be negligible. Ambient HONO concentration was measured simultaneously in downtown Albany, NY, by this method and by an ion chromatographic technique after sampling using a fritted bubbler. The results, from 70 pptv during the day to 1.7 ppbv in the early morning, were in very good agreement from the two techniques, within {+-} 20%.« less

Surgical scrubbing: can we clean up our carbon footprints by washing our hands?

PubMed

Somner, J E A; Stone, N; Koukkoulli, A; Scott, K M; Field, A R; Zygmunt, J

2008-11-01

A growing scientific consensus states that the global climate is changing and that human activity is responsible for these changes. It folLows that each of us has a responsibility to look at how our own lives impact on the environment. This study aimed to investigate water use during surgical scrubbing. Two water delivery systems were assessed to see whether technological innovation can promote more 'environmentally friendly' scrubbing behaviour. At least 10 different individuals, comprising surgeons, assistants and scrub nurses, were observed at two sites. Twenty-five separate surgical scrubs were observed in each location and the length of time for which the tap was on recorded. The tap was on during surgical scrubbing for a mean of 2 min 23 s at Gartnavel General Hospital (maximum: 4 min 37 s; minimum: 49 s; SD: 55 s) and for a mean of 1 min 7 s at Stobhill Hospital (maximum: 2 min 25 s; minimum: 19 s; SD: 33 s). The mean 'tap on' time (in seconds) at Gartnavel was significantly greater than that at Stobhill [t(39.5)=P<0.001]. A different tap design resulted in a net saving of 5.7 L of hot water, approximately 600 kJ of energy and 80 g of carbon dioxide emitted per surgical scrub. Surgical scrubbing is a ubiquitous procedure performed daily in healthcare settings. A simple technological solution can reduce water and energy use by modifying hand-washing behaviour and thereby reduce the carbon footprint of surgical scrubbing.

A Spatiotemporal Database to Track Human Scrub Typhus Using the VectorMap Application

PubMed Central

Kelly, Daryl J.; Foley, Desmond H.; Richards, Allen L.

2015-01-01

Scrub typhus is a potentially fatal mite-borne febrile illness, primarily of the Asia-Pacific Rim. With an endemic area greater than 13 million km2 and millions of people at risk, scrub typhus remains an underreported, often misdiagnosed febrile illness. A comprehensive, updatable map of the true distribution of cases has been lacking, and therefore the true risk of disease within the very large endemic area remains unknown. The purpose of this study was to establish a database and map to track human scrub typhus. An online search using PubMed and the United States Armed Forces Pest Management Board Literature Retrieval System was performed to identify articles describing human scrub typhus cases both within and outside the traditionally accepted endemic regions. Using World Health Organization guidelines, stringent criteria were used to establish diagnoses for inclusion in the database. The preliminary screening of 181 scrub typhus publications yielded 145 publications that met the case criterion, 267 case records, and 13 serosurvey records that could be georeferenced, describing 13,739 probable or confirmed human cases in 28 countries. A map service has been established within VectorMap (www.vectormap.org) to explore the role that relative location of vectors, hosts, and the pathogen play in the transmission of mite-borne scrub typhus. The online display of scrub typhus cases in VectorMap illustrates their presence and provides an up-to-date geographic distribution of proven scrub typhus cases. PMID:26678263

A Spatiotemporal Database to Track Human Scrub Typhus Using the VectorMap Application.

PubMed

Kelly, Daryl J; Foley, Desmond H; Richards, Allen L

2015-12-01

Scrub typhus is a potentially fatal mite-borne febrile illness, primarily of the Asia-Pacific Rim. With an endemic area greater than 13 million km2 and millions of people at risk, scrub typhus remains an underreported, often misdiagnosed febrile illness. A comprehensive, updatable map of the true distribution of cases has been lacking, and therefore the true risk of disease within the very large endemic area remains unknown. The purpose of this study was to establish a database and map to track human scrub typhus. An online search using PubMed and the United States Armed Forces Pest Management Board Literature Retrieval System was performed to identify articles describing human scrub typhus cases both within and outside the traditionally accepted endemic regions. Using World Health Organization guidelines, stringent criteria were used to establish diagnoses for inclusion in the database. The preliminary screening of 181 scrub typhus publications yielded 145 publications that met the case criterion, 267 case records, and 13 serosurvey records that could be georeferenced, describing 13,739 probable or confirmed human cases in 28 countries. A map service has been established within VectorMap (www.vectormap.org) to explore the role that relative location of vectors, hosts, and the pathogen play in the transmission of mite-borne scrub typhus. The online display of scrub typhus cases in VectorMap illustrates their presence and provides an up-to-date geographic distribution of proven scrub typhus cases.

Factors that influence the non-technical skills performance of scrub nurses: a prospective study.

PubMed

Kang, Evelyn; Massey, Debbie; Gillespie, Brigid M

2015-12-01

To identify and describe the factors that impact on the performance of scrub nurses' non-technical skills performance during the intra-operative phase of surgery. Non-technical skills have been identified as important precursors to errors in the operating room. However, few studies have investigated factors influencing non-technical skills of scrub nurses. Prospective observational study. Structured observations were performed on a sample of 182 surgical procedures across eight specialities by two trained observers from August 2012-April 2013 at two hospital sites. Participants were purposively selected scrub nurses. Bivariate correlations and a multiple linear regression model were used to identify associations among length of surgery, patients' acuity using the American Society of Anesthesiologists classification system, team familiarity, number of occasions scout nurses leave the operating room, change of scout nurse and the outcome, the non-technical skills performance of scrub nurses. Patient acuity and team familiarity were the strongest predictors of scrub nurses' non-technical skills performance at hospital site A. There were no correlations between the predictors and the performance of scrub nurses at hospital site B. A dedicated surgical team and patient acuity potentially influence the performance of scrub nurses' non-technical skills. Familiarity with team members foster advanced planning, thus minimizing distractions and interruptions that impact on scrub nurses' performance. Development of interventions aimed at improving non-technical skills has the potential to make a substantial difference and enhance patient care. © 2015 John Wiley & Sons Ltd.

Analytical methods for toxic gases from thermal degradation of polymers

NASA Technical Reports Server (NTRS)

Hsu, M.-T. S.

1977-01-01

Toxic gases evolved from the thermal oxidative degradation of synthetic or natural polymers in small laboratory chambers or in large scale fire tests are measured by several different analytical methods. Gas detector tubes are used for fast on-site detection of suspect toxic gases. The infrared spectroscopic method is an excellent qualitative and quantitative analysis for some toxic gases. Permanent gases such as carbon monoxide, carbon dioxide, methane and ethylene, can be quantitatively determined by gas chromatography. Highly toxic and corrosive gases such as nitrogen oxides, hydrogen cyanide, hydrogen fluoride, hydrogen chloride and sulfur dioxide should be passed into a scrubbing solution for subsequent analysis by either specific ion electrodes or spectrophotometric methods. Low-concentration toxic organic vapors can be concentrated in a cold trap and then analyzed by gas chromatography and mass spectrometry. The limitations of different methods are discussed.

Evaluation of nitrous oxide as a substitute for sulfur hexafluoride to reduce global warming impacts of ANSI/HPS N13.1 gaseous uniformity testing

NASA Astrophysics Data System (ADS)

Yu, Xiao-Ying; Barnett, J. Matthew; Amidan, Brett G.; Recknagle, Kurtis P.; Flaherty, Julia E.; Antonio, Ernest J.; Glissmeyer, John A.

2018-03-01

The ANSI/HPS N13.1-2011 standard requires gaseous tracer uniformity testing for sampling associated with stacks used in radioactive air emissions. Sulfur hexafluoride (SF6), a greenhouse gas with a high global warming potential, has long been the gas tracer used in such testing. To reduce the impact of gas tracer tests on the environment, nitrous oxide (N2O) was evaluated as a potential replacement to SF6. The physical evaluation included the development of a test plan to record percent coefficient of variance and the percent maximum deviation between the two gases while considering variables such as fan configuration, injection position, and flow rate. Statistical power was calculated to determine how many sample sets were needed, and computational fluid dynamic modeling was utilized to estimate overall mixing in stacks. Results show there are no significant differences between the behaviors of the two gases, and SF6 modeling corroborated N2O test results. Although, in principle, all tracer gases should behave in an identical manner for measuring mixing within a stack, the series of physical tests guided by statistics was performed to demonstrate the equivalence of N2O testing to SF6 testing in the context of stack qualification tests. The results demonstrate that N2O is a viable choice leading to a four times reduction in global warming impacts for future similar compliance driven testing.

Status epilepticus in scrub typhus.

PubMed

Kalita, Jayantee; Mani, Vinita E; Bhoi, Sanjeev K; Misra, Usha K

2016-07-01

Scrub typhus is an emerging infection, and there is little information about status epilepticus (SE) in scrub typhus. We report the clinical spectrum and outcome of SE in scrub typhus. In a 3-year prospective hospital-based observational study, all scrub typhus patients with SE were included. Scrub typhus was diagnosed by immunochromatography assay. SE was defined if convulsions lasted longer than 5 min. The patients' demographic, clinical, computed tomography (CT), magnetic resonance imaging (MRI), and electroencephalography (EEG) findings were noted. Response to antiepileptic drugs (AEDs) and outcome at 1 month and 1 year were recorded. Between 2012 and 2014, there were 66 patients with scrub typhus admitted with central nervous system (CNS) involvement, 10 (15.2%) of whom had SE (generalized convulsions in 5, secondary generalized in one). The median age of the patients was 34 (range 18-71) years and seven were female. The duration of SE ranged between 10 min and 48 h. SE responded to one AED in five patients, two AEDs in three patients, and more than two AEDs in two patients. Cranial MRI findings were normal. All patients recovered completely with doxycycline by 1 month and AED was withdrawn by 8 months in all. Although 15% patients with scrub typhus may have SE, they have good outcome. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

40 CFR 60.715 - Test methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... base film (i.e., the sample shall include any dilution solvent or other VOC added during the... for gas analysis. (f) Method 4 is used for stack gas moisture. (g) Methods 2, 2A, 2C, 2D, 3, and 4...

Scrubbing technique for needleless connectors to minimize contamination risk.

PubMed

Satou, K; Kusanagi, R; Nishizawa, A; Hori, S

2018-03-21

This study aimed to investigate the appropriate scrubbing technique for needleless connectors to minimize contamination risk. To demonstrate a highly effective scrubbing technique to physically eliminate bacteria, needleless connectors were contaminated with Geobacillus stearothermophilus spores and then scrubbed. The study showed that the highest bacterial elimination rate was achieved by scrubbing an access port in a straight line with an alcohol cotton swab, applying a force that was almost equal to an arterial compression haemostasis to the access port, and repeating this procedure once using a new alcohol cotton swab. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Boiler Stack Gas Heat Recovery

DTIC Science & Technology

1987-09-01

flue gas environ- ment. Conventional finned metal (aluminum, copper, stainless steel) tubes should not be used unless controls maintain the outer metal...xý Table 5. Summary of Actual Applications of Fiberglass Reinforced Plastic (FRP) in Corrosive Flue Gas Desulfurization Service Equipment Corrosive...process-steam/water heating. The procedure for estimating the energy potential of a given flue - gas stream is explained in detail with sample plots

Boiler Briquette Coal versus Raw Coal: Part I-Stack Gas Emissions.

PubMed

Ge, Su; Bai, Zhipeng; Liu, Weili; Zhu, Tan; Wang, Tongjian; Qing, Sheng; Zhang, Junfeng

2001-04-01

Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM 10 and PM 2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM 10 , 0.38 for PM 25 , 20.7 for SO 2 , and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM 10 , 0.30 for PM 2 5 , 7.5 for SO 2 , and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM 10 , 0.87 for PM 25 , 46.7 for SO 2 , and 15 for CO, while those of the BB-coal were 2.51 for PM 10 , 0.79 for PM 2.5 , 19.9 for SO 2 , and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/ steam conversion factors, were 0.23 for PM 10 , 0.12 for PM 2.5 , 6.4 for SO 2 , and 2.0 for CO, while those of the BB-coal were 0.30 for PM 10 , 0.094 for PM 2.5 , 2.4 for SO 2 , and 1.7 for CO. PM 10 and PM 2.5 elemental compositions are also presented for both types of coal tested in the study.

Boiler briquette coal versus raw coal: Part I--Stack gas emissions.

PubMed

Ge, S; Bai, Z; Liu, W; Zhu, T; Wang, T; Qing, S; Zhang, J

2001-04-01

Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM2.5, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2.5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM2.5, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.

A comparative study of hepatitis caused by scrub typhus and viral hepatitis A in South Korea.

PubMed

Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Byeon, Yu Mi; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo; Han, Mi Ah

2011-11-01

We compared clinical features and laboratory findings of 104 patients with hepatitis A and 197 patients with scrub typhus. Nausea, vomiting, abdominal pain, hepatomegaly, and jaundice were common in patient with hepatitis A, and fever and headache were significantly more common in patients with scrub typhus. At presentation, an alanine aminotransferase (ALT) level ≥ 500 U/L was observed in 1% of scrub typhus patients and in 87.5% of hepatitis A patients (P < 0.001). A bilirubin level ≥ 1.3 mg/dL was observed in 16.8% of scrub typhus patients and 90.4% of hepatitis A patients. The ALT:lactate dehydrogenase ratio was ≤ 5 in 97.4% of the patients with scrub typhus and > 5 in 95.2% of those with hepatitis A (P < 0.001). Fever, headache, rash, and eschar are findings that indicate scrub typhus. An ALT level ≥ 500 U/L (adjusted odds ratio = 0.011) a bilirubin level ≥ 1.3 (adjusted odds ratio = 0.024), an ALT:lactate dehydrogenase ratio > 5, and hepatomegaly are indications of viral hepatitis A.

A Comparative Study of Hepatitis Caused by Scrub Typhus and Viral Hepatitis A in South Korea

PubMed Central

Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Byeon, Yu Mi; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo; Han, Mi Ah

2011-01-01

We compared clinical features and laboratory findings of 104 patients with hepatitis A and 197 patients with scrub typhus. Nausea, vomiting, abdominal pain, hepatomegaly, and jaundice were common in patient with hepatitis A, and fever and headache were significantly more common in patients with scrub typhus. At presentation, an alanine aminotransferase (ALT) level ≥ 500 U/L was observed in 1% of scrub typhus patients and in 87.5% of hepatitis A patients (P < 0.001). A bilirubin level ≥ 1.3 mg/dL was observed in 16.8% of scrub typhus patients and 90.4% of hepatitis A patients. The ALT:lactate dehydrogenase ratio was ≤ 5 in 97.4% of the patients with scrub typhus and > 5 in 95.2% of those with hepatitis A (P < 0.001). Fever, headache, rash, and eschar are findings that indicate scrub typhus. An ALT level ≥ 500 U/L (adjusted odds ratio = 0.011) a bilirubin level ≥ 1.3 (adjusted odds ratio = 0.024), an ALT:lactate dehydrogenase ratio > 5, and hepatomegaly are indications of viral hepatitis A. PMID:22049041

DECONTAMINATION OF NEUTRON-IRRADIATED REACTOR FUEL

DOEpatents

Buyers, A.G.; Rosen, F.D.; Motta, E.E.

1959-12-22

A pyrometallurgical method of decontaminating neutronirradiated reactor fuel is presented. In accordance with the invention, neutron-irradiated reactor fuel may be decontaminated by countercurrently contacting the fuel with a bed of alkali and alkaine fluorides under an inert gas atmosphere and inductively melting the fuel and tracking the resulting descending molten fuel with induction heating as it passes through the bed. By this method, a large, continually fresh surface of salt is exposed to the descending molten fuel which enhances the efficiency of the scrubbing operation.

PEM fuel cell monitoring system

DOEpatents

Meltser, Mark Alexander; Grot, Stephen Andreas

1998-01-01

Method and apparatus for monitoring the performance of H.sub.2 --O.sub.2 PEM fuel cells. Outputs from a cell/stack voltage monitor and a cathode exhaust gas H.sub.2 sensor are corrected for stack operating conditions, and then compared to predetermined levels of acceptability. If certain unacceptable conditions coexist, an operator is alerted and/or corrective measures are automatically undertaken.

Analyzing the effectiveness of a frame-level redundancy scrubbing technique for SRAM-based FPGAs

DOE PAGES

Tonfat, Jorge; Lima Kastensmidt, Fernanda; Rech, Paolo; ...

2015-12-17

Radiation effects such as soft errors are the major threat to the reliability of SRAM-based FPGAs. This work analyzes the effectiveness in correcting soft errors of a novel scrubbing technique using internal frame redundancy called Frame-level Redundancy Scrubbing (FLR-scrubbing). This correction technique can be implemented in a coarse grain TMR design. The FLR-scrubbing technique was implemented on a mid-size Xilinx Virtex-5 FPGA device used as a case study. The FLR-scrubbing technique was tested under neutron radiation and fault injection. Implementation results demonstrated minimum area and energy consumption overhead when compared to other techniques. The time to repair the fault ismore » also improved by using the Internal Configuration Access Port (ICAP). Lastly, neutron radiation test results demonstrated that the proposed technique is suitable for correcting accumulated SEUs and MBUs.« less

Analyzing the effectiveness of a frame-level redundancy scrubbing technique for SRAM-based FPGAs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tonfat, Jorge; Lima Kastensmidt, Fernanda; Rech, Paolo

Radiation effects such as soft errors are the major threat to the reliability of SRAM-based FPGAs. This work analyzes the effectiveness in correcting soft errors of a novel scrubbing technique using internal frame redundancy called Frame-level Redundancy Scrubbing (FLR-scrubbing). This correction technique can be implemented in a coarse grain TMR design. The FLR-scrubbing technique was implemented on a mid-size Xilinx Virtex-5 FPGA device used as a case study. The FLR-scrubbing technique was tested under neutron radiation and fault injection. Implementation results demonstrated minimum area and energy consumption overhead when compared to other techniques. The time to repair the fault ismore » also improved by using the Internal Configuration Access Port (ICAP). Lastly, neutron radiation test results demonstrated that the proposed technique is suitable for correcting accumulated SEUs and MBUs.« less

40 CFR 98.172 - GHGs to report.

Code of Federal Regulations, 2014 CFR

2014-07-01

... combustion units include, but are not limited to, by-product recovery coke oven battery combustion stacks... flares that burn blast furnace gas or coke oven gas according to the procedures in § 98.253(b)(1) of...)(B) and § 98.253(b)(1)(iii)(C), you must use the default CO2 emission factors for coke oven gas and...

40 CFR 98.172 - GHGs to report.

Code of Federal Regulations, 2012 CFR

2012-07-01

... combustion units include, but are not limited to, by-product recovery coke oven battery combustion stacks... flares that burn blast furnace gas or coke oven gas according to the procedures in § 98.253(b)(1) of...)(B) and § 98.253(b)(1)(iii)(C), you must use the default CO2 emission factors for coke oven gas and...

40 CFR 98.172 - GHGs to report.

Code of Federal Regulations, 2010 CFR

2010-07-01

... combustion units include, but are not limited to, by-product recovery coke oven battery combustion stacks... except you must use the default CO2 emission factors for coke oven gas and blast furnace gas from Table C... flares according to the requirements in § 98.33(c)(2) using the emission factors for coke oven gas and...

40 CFR 98.172 - GHGs to report.

Code of Federal Regulations, 2013 CFR

2013-07-01

... combustion units include, but are not limited to, by-product recovery coke oven battery combustion stacks... flares that burn blast furnace gas or coke oven gas according to the procedures in § 98.253(b)(1) of...)(B) and § 98.253(b)(1)(iii)(C), you must use the default CO2 emission factors for coke oven gas and...

40 CFR 98.172 - GHGs to report.

Code of Federal Regulations, 2011 CFR

2011-07-01

... combustion units include, but are not limited to, by-product recovery coke oven battery combustion stacks... flares that burn blast furnace gas or coke oven gas according to the procedures in § 98.253(b)(1) of...)(B) and § 98.253(b)(1)(iii)(C), you must use the default CO2 emission factors for coke oven gas and...

40 CFR Table 1 to Subpart Bbbbb of... - Requirements for Performance Tests

Code of Federal Regulations, 2014 CFR

2014-07-01

... HAP used as the calibration gas must be the single organic HAP representing the largest percent of... determining compliance with a ppmv concentration limit. c. Conduct gas molecular weight analysis i. Method 3... York, NY 10016-5990) as an alternative to EPA Method 3B. d. Measure moisture content of the stack gas...

PRELIMINARY RESULTS OF THE AGC-4 IRRADIATION IN THE ADVANCED TEST REACTOR AND DESIGN OF AGC-5 (HTR16-18469)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davenport, Michael; Petti, D. A.

The United States Department of Energy’s Advanced Reactor Technologies (ART) Program will irradiate up to six nuclear graphite creep experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The graphite experiments are being irradiated over an approximate eight year period to support development of a graphite irradiation performance data base on the new nuclear grade graphites now available for use in high temperature gas reactors. The goals of the irradiation experiments are to obtain irradiation performance data, including irradiation creep, at different temperatures and loading conditions to support design of the Very High Temperature Gasmore » Reactor (VHTR), as well as other future gas reactors. The experiments each consist of a single capsule that contain six stacks of graphite specimens, with half of the graphite specimens in each stack under a compressive load, while the other half of the specimens are not be subjected to a compressive load during irradiation. The six stacks have differing compressive loads applied to the top half of diametrically opposite pairs of specimen stacks. A seventh specimen stack in the center of the capsule does not have a compressive load. The specimens are being irradiated in an inert sweep gas atmosphere with on-line temperature and compressive load monitoring and control. There are also samples taken of the sweep gas effluent to measure any oxidation or off-gassing of the specimens that may occur during initial start-up of the experiment. The first experiment, AGC-1, started its irradiation in September 2009, and the irradiation was completed in January 2011. The second experiment, AGC-2, started its irradiation in April 2011 and completed its irradiation in May 2012. The third experiment, AGC-3, started its irradiation in late November 2012 and completed in the April of 2014. AGC-4 is currently being irradiated in the ATR. This paper will briefly discuss the preliminary irradiation results of the AGC-4 experiment, as well as the design of AGC-5.« less

Exhaust-stack nozzle area and shape for individual cylinder exhaust-gas jet-propulsion system

NASA Technical Reports Server (NTRS)

Pinkel, Benjamin; Turner, Richard; Voss, Fred; Humble, Leroy V

1943-01-01

This report presents the results of an investigation conducted on the effect of exhaust-stack nozzle area, shape, and length on engine power, jet thrust, and gain in net thrust (engine propeller plus jet). Single-cylinder engine data were obtained using three straight stacks 25, 44, and 108 inches in length; an S-shaped stack, a 90 degree bend, a 180 degree bend, and a short straight stack having a closed branch faired into it. Each stack was fitted with nozzles varying in exit area from 0.91 square inch to the unrestricted area of the stack of 4.20 square inches. The engine was generally operated over a range of engine speeds from 1300 to 2100 r.p.m, inlet-manifold pressures from 22 to 30 inches of mercury absolute, and a fuel-air ratio of 0.08. The loss in engine power, the jet thrust, and the gain in net thrust are correlated in terms of several simple parameters. An example is given for determining the optimum nozzle area and the overall net thrust.

Laser Doppler systems in pollution monitoring

NASA Technical Reports Server (NTRS)

Miller, C. R.; Sonnenschein, C. M.; Herget, W. F.; Huffaker, R. M.

1976-01-01

The paper reports on a program undertaken to determine the feasibility of using a laser Doppler velocimeter (LDV) to measure smoke-stack gas exit velocity, particulate concentration, and mass flow. Measurements made with a CO2 laser Doppler radar system at a coal-burning power plant are compared with in-stack measurements made by a pitot tube. The operational principles of a LDV are briefly described along with the system employed in the present study. Data discussed include typical Doppler spectra from smoke-stack effluents at various laser elevation angles, the measured velocity profile across the stack exit, and the LDV-measured exit velocity as a function of the exit velocity measured by the in-stack instrument. The in-stack velocity is found to be about 14% higher than the LDV velocity, but this discrepancy is regarded as a systematic error. In general, linear relationships are observed between the laser data, the exit velocity, and the particulate concentration. It is concluded that an LDV has the capability of determining both the mass concentration and the mass flow from a power-plant smoke stack.

Bayesian spatial modelling and the significance of agricultural land use to scrub typhus infection in Taiwan.

PubMed

Wardrop, Nicola A; Kuo, Chi-Chien; Wang, Hsi-Chieh; Clements, Archie C A; Lee, Pei-Fen; Atkinson, Peter M

2013-11-01

Scrub typhus is transmitted by the larval stage of trombiculid mites. Environmental factors, including land cover and land use, are known to influence breeding and survival of trombiculid mites and, thus, also the spatial heterogeneity of scrub typhus risk. Here, a spatially autoregressive modelling framework was applied to scrub typhus incidence data from Taiwan, covering the period 2003 to 2011, to provide increased understanding of the spatial pattern of scrub typhus risk and the environmental and socioeconomic factors contributing to this pattern. A clear spatial pattern in scrub typhus incidence was observed within Taiwan, and incidence was found to be significantly correlated with several land cover classes, temperature, elevation, normalized difference vegetation index, rainfall, population density, average income and the proportion of the population that work in agriculture. The final multivariate regression model included statistically significant correlations between scrub typhus incidence and average income (negatively correlated), the proportion of land that contained mosaics of cropland and vegetation (positively correlated) and elevation (positively correlated). These results highlight the importance of land cover on scrub typhus incidence: mosaics of cropland and vegetation represent a transitional land cover type which can provide favourable habitats for rodents and, therefore, trombiculid mites. In Taiwan, these transitional land cover areas tend to occur in less populated and mountainous areas, following the frontier establishment and subsequent partial abandonment of agricultural cultivation, due to demographic and socioeconomic changes. Future land use policy decision-making should ensure that potential public health outcomes, such as modified risk of scrub typhus, are considered.

Burden of Disease Measured by Disability-Adjusted Life Years and a Disease Forecasting Time Series Model of Scrub Typhus in Laiwu, China

PubMed Central

Yang, Li-Ping; Liang, Si-Yuan; Wang, Xian-Jun; Li, Xiu-Jun; Wu, Yan-Ling; Ma, Wei

2015-01-01

Background Laiwu District is recognized as a hyper-endemic region for scrub typhus in Shandong Province, but the seriousness of this problem has been neglected in public health circles. Methodology/Principal Findings A disability-adjusted life years (DALYs) approach was adopted to measure the burden of scrub typhus in Laiwu, China during the period 2006 to 2012. A multiple seasonal autoregressive integrated moving average model (SARIMA) was used to identify the most suitable forecasting model for scrub typhus in Laiwu. Results showed that the disease burden of scrub typhus is increasing yearly in Laiwu, and which is higher in females than males. For both females and males, DALY rates were highest for the 60–69 age group. Of all the SARIMA models tested, the SARIMA(2,1,0)(0,1,0)12 model was the best fit for scrub typhus cases in Laiwu. Human infections occurred mainly in autumn with peaks in October. Conclusions/Significance Females, especially those of 60 to 69 years of age, were at highest risk of developing scrub typhus in Laiwu, China. The SARIMA (2,1,0)(0,1,0)12 model was the best fit forecasting model for scrub typhus in Laiwu, China. These data are useful for developing public health education and intervention programs to reduce disease. PMID:25569248

Acute transverse myelitis following scrub typhus: A case report and review of the literature.

PubMed

Ryu, Hyun-Seung; Moon, Bong Ju; Park, Jae-Young; Kim, Sang-Deok; Seo, Seung-Kwon; Lee, Jung-Kil

2018-01-19

Context Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi. The disease can usually involve the lungs, heart, liver, spleen and brain through hematogenous dissemination. However, very rarely, acute transverse myelitis in the spinal cord develops from scrub typhus. We present a case of acute transverse myelitis following scrub typhus with a review of the literature. Findings A 66-year-old male visited a hospital for general myalgia, mild headache, and fever in October. He was noted to have thick, black papule skin on his abdomen, which was highly suggestive of scrub typhus. To confirm the diagnosis, O. tsutsugamushi antibody titers were examined and detected highly in serum by an indirect fluorescence antibody assay. Doxycycline, the standard treatment for scrub typhus, was administered. However, after seven days of treatment, he rapidly developed weakness in the right leg, paresthesia in both lower limbs, and voiding difficulty. Spinal magnetic resonance imaging (MRI) revealed lesions with high signal intensity involving the spinal cord at the thoracolumbar junction. Paraparesis gradually improved following steroid pulse therapy for five days. At one-year follow-up, he could walk without cane. Conclusions Orientia tsutsugamushi causes scrub typhus, which can affect not only the brain, but also the spinal cord. Although acute transverse myelitis develops rarely from scrub typhus, this should be considered as differential diagnosis in patients of fever with neurological deficit in endemic areas.

ACUTE CHOLECYSTITIS AS AN UNUSUAL PRESENTATION OF SCRUB TYPHUS: A REPORT OF TWO CASES AND REVIEW OF THE LITERATURE.

PubMed

Charoenphak, Sirima; Rattanawong, Pattara; Sungkanuparph, Somnuek

2017-01-01

Scrub typhus rarely presents with acute cholecystitis. We present 2 cases of scrub typhus with cholecystitis. The first patient is a 62 year old female who presented to the hospital with fever and body aches for 1 week and right upper quadrant abdominal pain for 3 days. She gave a history of an insect bite 2 weeks previously. She was diagnosed as having acute cholecystitis and underwent cholecystectomy. She continued with fever post-operatively and physical examination revealed an eschar. She had an immunofluorescence assay (IFA) performed that revealed a high IgM titer for Orientia tsutsugamushi. She was diagnosed as having scrub typhus, treated with doxycycline and she recovered completely. The second patient also presented to the hospital with a 1 week history of fever and upper quadrant abdominal pain. She was diagnosed with having cholecystitis. Her symptoms did not improve with intravenous antibiotics and further investigation revealed elevated titers for O. tsutsugamushi and Leptospira interrogans. She was diagnosed as having a co-infection of scrub typhus and leptospirosis and treated with doxycycline. She recovered completely. Patients from scrub typhus endemic regions who present with acute cholecystitis but do not respond to traditional treatment should be tested for scrub typhus and leptospirosis and should have a careful admission physical examination looking for eschar formation, since scrub typhus may present with acute cholecystitis.

Masticophis flagellum selects florida scrub habitat at multiple spatial scales

USGS Publications Warehouse

Halstead, B.J.; Mushinsky, H.R.; McCoy, E.D.

2009-01-01

The use of space by individual animals strongly influences the spatial extent, abundance, and growth rates of their populations. We analyzed the spatial ecology and habitat selection of Masticophis flagellum (the coachwhip) at three different scales to determine which habitats are most important to this species. Home ranges and mean daily displacements of M. flagellum in Florida were large compared to individuals in other populations of this species. Home ranges contained a greater proportion of Florida scrub habitat than did the study site as a whole, and individuals selected Florida scrub habitat within their home ranges. For both selection of the home range within the study site and selection of habitats within the home range, mesic cutthroat and hydric swamp habitats were avoided. Standardized selection ratios of Florida scrub patches were positively correlated with lizard abundance. Several non-mutually exclusive mechanisms, including foraging success (prey abundance, prey vulnerability, and foraging efficiency), abundance of refugia, and thermoregulatory opportunity may underlie the selection of Florida scrub by M. flagellum. Historic rarity and anthropogenic loss and fragmentation of Florida scrub habitat, coupled with the long-distance movements, large home ranges, and selection of Florida scrub by M. flagellum, indicate that large contiguous tracts of land containing Florida scrub will be essential for the persistence of M. flagellum in central Florida. ?? 2009 by The Herpetologists' League, Inc.

75 FR 56133 - Savannah Coastal Refuges' Complex, GA and SC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-15

..., open waters, forested habitats, scrub/shrub habitats, grasslands, and open lands. All ponds, levees... management programs for impoundments, beaches, wetlands, open waters, forested habitats, scrub/shrub habitats... habitat management strategy. Impoundments, beaches, wetlands, open waters, forested habitats, scrub/shrub...

Device for equalizing molten electrolyte content in a fuel cell stack

DOEpatents

Smith, J.L.

1985-12-23

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

Device for equalizing molten electrolyte content in a fuel cell stack

DOEpatents

Smith, James L.

1987-01-01

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

PEM fuel cell bipolar plate material requirements for transportation applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borup, R.L.; Stroh, K.R.; Vanderborgh, N.E.

1996-04-01

Cost effective bipolar plates are currently under development to help make proton exchange membrane (PEM) fuel cells commercially viable. Bipolar plates separate individual cells of the fuel cell stack, and thus must supply strength, be electrically conductive, provide for thermal control of the fuel stack, be a non-porous materials separating hydrogen and oxygen feed streams, be corrosion resistant, provide gas distribution for the feed streams and meet fuel stack cost targets. Candidate materials include conductive polymers and metal plates with corrosion resistant coatings. Possible metals include aluminium, titanium, iron/stainless steel and nickel.

Estimating the burden of scrub typhus: A systematic review.

PubMed

Bonell, Ana; Lubell, Yoel; Newton, Paul N; Crump, John A; Paris, Daniel H

2017-09-01

Scrub typhus is a vector-borne zoonotic disease that can be life-threatening. There are no licensed vaccines, or vector control efforts in place. Despite increasing awareness in endemic regions, the public health burden and global distribution of scrub typhus remains poorly known. We systematically reviewed all literature from public health records, fever studies and reports available on the Ovid MEDLINE, Embase Classic + Embase and EconLit databases, to estimate the burden of scrub typhus since the year 2000. In prospective fever studies from Asia, scrub typhus is a leading cause of treatable non-malarial febrile illness. Sero-epidemiological data also suggest that Orientia tsutsugamushi infection is common across Asia, with seroprevalence ranging from 9.3%-27.9% (median 22.2% IQR 18.6-25.7). A substantial apparent rise in minimum disease incidence (median 4.6/100,000/10 years, highest in China with 11.2/100,000/10 years) was reported through passive national surveillance systems in South Korea, Japan, China, and Thailand. Case fatality risks from areas of reduced drug-susceptibility are reported at 12.2% and 13.6% for South India and northern Thailand, respectively. Mortality reports vary widely around a median mortality of 6.0% for untreated and 1.4% for treated scrub typhus. Limited evidence suggests high mortality in complicated scrub typhus with CNS involvement (13.6% mortality), multi-organ dysfunction (24.1%) and high pregnancy miscarriage rates with poor neonatal outcomes. Scrub typhus appears to be a truly neglected tropical disease mainly affecting rural populations, but increasingly also metropolitan areas. Rising minimum incidence rates have been reported over the past 8-10 years from countries with an established surveillance system. A wider distribution of scrub typhus beyond Asia is likely, based on reports from South America and Africa. Unfortunately, the quality and quantity of the available data on scrub typhus epidemiology is currently too limited for any economical, mathematical modeling or mapping approaches.

Estimating the burden of scrub typhus: A systematic review

PubMed Central

Bonell, Ana; Lubell, Yoel; Newton, Paul N.; Crump, John A.

2017-01-01

Background Scrub typhus is a vector-borne zoonotic disease that can be life-threatening. There are no licensed vaccines, or vector control efforts in place. Despite increasing awareness in endemic regions, the public health burden and global distribution of scrub typhus remains poorly known. Methods We systematically reviewed all literature from public health records, fever studies and reports available on the Ovid MEDLINE, Embase Classic + Embase and EconLit databases, to estimate the burden of scrub typhus since the year 2000. Findings In prospective fever studies from Asia, scrub typhus is a leading cause of treatable non-malarial febrile illness. Sero-epidemiological data also suggest that Orientia tsutsugamushi infection is common across Asia, with seroprevalence ranging from 9.3%–27.9% (median 22.2% IQR 18.6–25.7). A substantial apparent rise in minimum disease incidence (median 4.6/100,000/10 years, highest in China with 11.2/100,000/10 years) was reported through passive national surveillance systems in South Korea, Japan, China, and Thailand. Case fatality risks from areas of reduced drug-susceptibility are reported at 12.2% and 13.6% for South India and northern Thailand, respectively. Mortality reports vary widely around a median mortality of 6.0% for untreated and 1.4% for treated scrub typhus. Limited evidence suggests high mortality in complicated scrub typhus with CNS involvement (13.6% mortality), multi-organ dysfunction (24.1%) and high pregnancy miscarriage rates with poor neonatal outcomes. Interpretation Scrub typhus appears to be a truly neglected tropical disease mainly affecting rural populations, but increasingly also metropolitan areas. Rising minimum incidence rates have been reported over the past 8–10 years from countries with an established surveillance system. A wider distribution of scrub typhus beyond Asia is likely, based on reports from South America and Africa. Unfortunately, the quality and quantity of the available data on scrub typhus epidemiology is currently too limited for any economical, mathematical modeling or mapping approaches. PMID:28945755

40 CFR 503.44 - Operational standard-total hydrocarbons.

Code of Federal Regulations, 2012 CFR

2012-07-01

... incinerator shall be corrected for zero percent moisture by multiplying the measured total hydrocarbons... the percent moisture in the sewage sludge incinerator exit gas in hundredths. (b) The total... the exit gas from a sewage sludge incinerator stack, corrected for zero percent moisture using the...

40 CFR 503.44 - Operational standard-total hydrocarbons.

Code of Federal Regulations, 2014 CFR

2014-07-01

... incinerator shall be corrected for zero percent moisture by multiplying the measured total hydrocarbons... the percent moisture in the sewage sludge incinerator exit gas in hundredths. (b) The total... the exit gas from a sewage sludge incinerator stack, corrected for zero percent moisture using the...

40 CFR 503.44 - Operational standard-total hydrocarbons.

Code of Federal Regulations, 2013 CFR

2013-07-01

... incinerator shall be corrected for zero percent moisture by multiplying the measured total hydrocarbons... the percent moisture in the sewage sludge incinerator exit gas in hundredths. (b) The total... the exit gas from a sewage sludge incinerator stack, corrected for zero percent moisture using the...

Effect of forming gas annealing on the degradation properties of Ge-based MOS stacks

NASA Astrophysics Data System (ADS)

Aguirre, F.; Pazos, S.; Palumbo, F. R. M.; Fadida, S.; Winter, R.; Eizenberg, M.

2018-04-01

The influence of forming gas annealing on the degradation at a constant stress voltage of multi-layered germanium-based Metal-Oxide-Semiconductor capacitors (p-Ge/GeOx/Al2O3/High-K/Metal Gate) has been analyzed in terms of the C-V hysteresis and flat band voltage as a function of both negative and positive stress fields. Significant differences were found for the case of negative voltage stress between the annealed and non-annealed samples, independently of the stressing time. It was found that the hole trapping effect decreases in the case of the forming gas annealed samples, indicating strong passivation of defects with energies close to the valence band existing in the oxide-semiconductor interface during the forming gas annealing. Finally, a comparison between the degradation dynamics of Germanium and III-V (n-InGaAs) MOS stacks is presented to summarize the main challenges in the integration of reliable Ge-III-V hybrid devices.

PEM fuel cell monitoring system

DOEpatents

Meltser, M.A.; Grot, S.A.

1998-06-09

Method and apparatus are disclosed for monitoring the performance of H{sub 2}--O{sub 2} PEM fuel cells. Outputs from a cell/stack voltage monitor and a cathode exhaust gas H{sub 2} sensor are corrected for stack operating conditions, and then compared to predetermined levels of acceptability. If certain unacceptable conditions coexist, an operator is alerted and/or corrective measures are automatically undertaken. 2 figs.

Co-infection of scrub typhus and leptospirosis in patients with pyrexia of unknown origin in Longding district of Arunachal Pradesh in 2013.

PubMed

Borkakoty, Biswajyoti; Jakharia, Aniruddha; Biswas, Dipankar; Mahanta, Jagadish

2016-01-01

Scrub typhus and leptospirosis are bacterial zoonotic disease causing high morbidity and mortality. The seasonal outbreak of pyrexia is common in Arunachal Pradesh (AP); many times the disease remains undiagnosed. An outbreak of pyrexia of unknown origin (PUO) occurred in Longding district of Arunachal Pradesh in 2013, with 108 deaths, which was investigated to elucidate the cause of illness. Blood samples from the affected region with acute pyrexia were collected, and screened for the malaria parasite, scrub typhus IgM and leptospira IgM. Scrub typhus IgM was reactive in 97% (30/31), and 25% (8/31) cases were co-infected with leptospira. Incidentally, scrub typhus reactive (67%) and leptospira co-infection (62.7%) were higher in females. Record of previous 3 years (2011-2013) from Longding, Community Health Centre showed an increase in indoor pyrexia cases by 2-fold or more during October and November. The present study is the first report of co-infection of scrub typhus with leptospirosis from Northeast India. Medical officers in this region should take scrub typhus and leptospirosis in their differential diagnosis of patients with PUO for early diagnosis and effective treatment.

Meteorological factors affecting scrub typhus occurrence: a retrospective study of Yamagata Prefecture, Japan, 1984-2014.

PubMed

Seto, J; Suzuki, Y; Nakao, R; Otani, K; Yahagi, K; Mizuta, K

2017-02-01

Climate change, by its influence on the ecology of vectors might affect the occurrence of vector-borne diseases. This study examines the effects of meteorological factors in Japan on the occurrence of scrub typhus, a mite-borne zoonosis caused by Orientia tsutsugamushi. Using negative binomial regression, we analysed the relationships between meteorological factors (including temperature, rainfall, snowfall) and spring-early summer cases of scrub typhus in Yamagata Prefecture, Japan, during 1984-2014. The average temperature in July and August of the previous year, cumulative rainfall in September of the previous year, snowfall throughout the winter, and maximum depth of snow cover in January and February were positively correlated with the number of scrub typhus cases. By contrast, cumulative rainfall in July of the previous year showed a negative relationship to the number of cases. These associations can be explained by the life-cycle of Leptotrombidium pallidum, a predominant vector of spring-early summer cases of scrub typhus in northern Japan. Our findings show that several meteorological factors are useful to estimate the number of scrub typhus cases before the endemic period. They are applicable to establish an early warning system for scrub typhus in northern Japan.

Increased level and interferon-γ production of circulating natural killer cells in patients with scrub typhus.

PubMed

Kang, Seung-Ji; Jin, Hye-Mi; Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook

2017-07-01

Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients.

Increased level and interferon-γ production of circulating natural killer cells in patients with scrub typhus

PubMed Central

Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung

2017-01-01

Background Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. Methodology/Principal findings This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. Conclusions This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients. PMID:28750012

Rapid Increase in Scrub Typhus Incidence in Mainland China, 2006-2014.

PubMed

Wu, Yi-Cheng; Qian, Quan; Magalhaes, Ricardo J Soares; Han, Zhi-Hai; Haque, Ubydul; Weppelmann, Thomas A; Hu, Wen-Biao; Liu, Yun-Xi; Sun, Yan-Song; Zhang, Wen-Yi; Li, Shen-Long

2016-03-01

Scrub typhus is a vector-borne disease, which has recently reemerged in China. In this study, we describe the distribution and incidence of scrub typhus cases in China from 2006 to 2014 and quantify differences in scrub typhus cases with respect to sex, age, and occupation. The results of our study indicate that the annual incidence of scrub typhus has increased during the study period. The number of cases peaked in 2014, which was 12.8 times greater than the number of cases reported in 2006. Most (77.97%) of the cases were reported in five provinces (Guangdong, Yunnan, Anhui, Fujian, and Shandong). Our study also demonstrates that the incidence rate of scrub typhus was significantly higher in females compared to males (P < 0.001) and was highest in the 60-69 year age group, and that farmers had a higher incidence rate than nonfarmers (P < 0.001). Different seasonal trends were identified in the number of reported cases between the northern and southern provinces of China. These findings not only demonstrate that China has experienced a large increase in scrub typhus incidence, but also document an expansion in the geographic distribution throughout the country. © The American Society of Tropical Medicine and Hygiene.

SOXAL{trademark} pilot plant demonstration at Niagara Mohawk`s Dunkirk Station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strangway, P.K.

This paper describes a six-month, nominal three megawatt (3 MW) pilot plant demonstration of the SOXAL{trademark} regenerative flue gas desulfurization (FGD) process at Niagara Mohawk Power Corporation`s Dunkirk, NY coal-fired power station. Using a slip-stream of flue gas from an actual coal-fired boiler, the pilot plant successfully demonstrated the absorption of sulfur dioxide and the simultaneous regeneration of sodium-based scrubbing liquor via bipolar membrane electrodialysis. Sulfur dioxide removal efficiency of greater than 98% was routinely achieved. The absorption and regeneration stages were both proven reliable and controllable. The pilot plant was successfully operated in both continuous and decoupled modes ofmore » operation, thus demonstrating the flexibility of this process.« less

Scrubbing intensification for sulphur and ammonia compounds removal.

PubMed

Couvert, A; Sanchez, C; Laplanche, A; Renner, C

2008-02-01

Operating conditions were optimised in a new compact scrubber in order to remove odorous sulphur (H(2)S and CH(3)SH) and ammonia compounds. The influence of the superficial gas and liquid velocities, pH, contactor length, inlet concentrations (sulphur compounds, ammonia, chlorine), and the mixing effects was characterised. Whereas abatement increased with velocities, pH and the chlorine concentration, an increase of inlet CH(3)SH concentration drove to a worse efficiency of process. Moreover, the contactor length and the presence of another pollutant in the gas phase only played a role on the methylmercaptan removal. Finally, the reactive consumptions were estimated at the outlet of the reactor. The chlorination by-product quantification permitted to understand the under-stoichiometry.

Removal of contaminant gases from an electrolytic urine pretreatment process. [in spacecraft life support systems

NASA Technical Reports Server (NTRS)

Colombo, G. V.; Putnam, D. F.

1977-01-01

The effluent gas stream from an electrolytic urine pretreatment process was analyzed by gas chromatography-mass spectroscopy and wet chemical methods to determine its composition. The major constituents were identified as: hydrogen, carbon dioxide, oxygen, nitrogen, water vapor, and chlorine. The trace impurities were chlorinated light hydrocarbons, and a number of other organic impurities in the low ppm range. Several methods of removing all of the undesirable gases to levels acceptable for return to a space cabin atmosphere were investigated experimentally. A subsystem concept comprised of the following sequential unit processes and operations was successfully demonstrated: (1) raw urine scrubbing, (2) silica gel sorption, (3) dilution with cabin air, and (4) catalytic oxidation.

[Spatio-temporal distribution of scrub typhus and related influencing factors in coastal beach area of Yancheng, China].

PubMed

Chen, Y Z; Li, F; Xu, H; Huang, L C; Gu, Z G; Sun, Z Y; Yan, G J; Zhu, Y J; Tang, C

2016-02-01

In order to provide better programs on monitoring, early warning and prevention of Scrub Typhus in the coastal beach area, temporal-spatial distribution characteristics of scrub typhus were summarized. Relationships between temporal-spatial clustering of Scrub Typhus, meteorological factors, rodent distribution and the biological characteristics in coastal beach area of Yancheng city, were studied. Reports on network-based Scrub Typhus epidemics and information on population, weather situation through monitoring those stations, from 2005 to 2014 were collected and processed, in the coastal beach area of Yancheng city. Distribution, density of the population concerned and seasonal fluctuation on rodents were monitored in coastal beach area, from April 2011 to December, 2013. METHODS as descriptive statistics, space-time permutation scantistics, autocorrelation and Cross-correlation analysis etc, were used to analyze the temporal-spatial distribution of Scrub Typhus and correlation with rodent distribution, density fluctuation and meteorological indexes. Zero-inflated Pearson (ZIP) regression model was contributed according to the distribution of related data. All methods were calculated under Excel 2003, SPSS 16.0, Mapinfo 11.0, Satscan 9.0 and Stata/SE 10.0 softwares. (1) The incidence of Scrub Typhus was gradually increasing and the highest incidence of the year was seen in 2014, as 5.81/10 million. There was an autumn peak of Scrub typhus, with the highest incidence rate as 12.02/10 million in November. The incidence rate of Scrub typhus appeared high in Binhai, Dafeng and Xiangshui, with the average incidence rates appeared as 3.30/10 million, 3.21/10 million and 2.79/10 million, respectively. There were 12 towns with high incidence rates in the coastal beach area, with incidence rate showed between 4.41/10 and 10.03/10 million. (2) There were three incidence clusters of Scrub typhus seen in 25 towns, between October 2012 and November 2012 in Dongtai, Dafeng, Sheyang areas and 5 towns between October and November, 2014 in Xiangshui area, together with another 6 towns in November of 2006, in Binhai area. (3) Apodemus agrarius appeared the dominant species in the coastal area, with the constituent ratio as 89.19%. The rodent density appeared two peaks in winter and summer in 2011 and 2013. The winter peak was seen in January and the summer peak lasting for 5-8 months. Scrub Typhus was seen 10-11 months in a year and the incidence was increasing, parallel with the peak of the rodent density. The peak incidence of Scrub Typhus showed a temperature/rainfall-related peak. Rodent density, temperature, rainfalls were correlated with the incidence of Scrub Typhus, under the Cross correlation analysis. Rains, Mean minimum temperature of a 3-month lagging were directly correlated but the duration of sunshine and relative humidity were negatively correlated with the incidence of Scrub Typhus, under the Zero-inflated Pearson (ZIP) regression model. Temporal-spatial clustering and factors as media creature and weather condition of Scrub Typhu were discovered, which provided evidence for effective measures on prevention and control of the disease.

PNNL Report on the Development of Bench-scale CFD Simulations for Gas Absorption across a Wetted Wall Column

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Canhai

This report is prepared for the demonstration of hierarchical prediction of carbon capture efficiency of a solvent-based absorption column. A computational fluid dynamics (CFD) model is first developed to simulate the core phenomena of solvent-based carbon capture, i.e., the CO2 physical absorption and chemical reaction, on a simplified geometry of wetted wall column (WWC) at bench scale. Aqueous solutions of ethanolamine (MEA) are commonly selected as a CO2 stream scrubbing liquid. CO2 is captured by both physical and chemical absorption using highly CO2 soluble and reactive solvent, MEA, during the scrubbing process. In order to provide confidence bound on themore » computational predictions of this complex engineering system, a hierarchical calibration and validation framework is proposed. The overall goal of this effort is to provide a mechanism-based predictive framework with confidence bound for overall mass transfer coefficient of the wetted wall column (WWC) with statistical analyses of the corresponding WWC experiments with increasing physical complexity.« less

Scrub typhus as a possible aetiology of Guillain-Barré syndrome: two cases.

PubMed

Lee, M-S; Lee, J-H; Lee, H-S; Chang, H; Kim, Y-S; Cho, K-H; Ahn, S-H; Song, J-H; Yoo, M; Han, J-K; Park, H-Y

2009-09-01

Neurological complications of scrub typhus are reported to be rare. Peripheral nervous system involvement has been reported in only one case. We present two cases of Guillan-Barré syndrome (GBS) associated with scrub typhus. In both cases, the findings of an elevated indirect immunofluorescent antibody titer for Orientia tsutsugamushi and nerve conduction study showing sensory-motor polyneuropathy, have led us to believe that scrub typhus could be one of the antecedent illnesses associated with GBS.

Activation of the coagulation cascade in patients with scrub typhus.

PubMed

Lee, Hee-Jeong; Park, Chi-Young; Park, Sang-Gon; Yoon, Na-Ra; Kim, Dong-Min; Chung, Choon-Hae

2017-09-01

This retrospective study aimed to evaluate the levels of coagulation factors and presence of disseminated intravascular coagulation (DIC) in patients with scrub typhus. We included patients confirmed to have scrub typhus at the Chosun University Hospital between September 2004 and December 2009. The DIC scores were evaluated in 365 patients and 36 healthy controls. The median concentrations of fibrinogen, d-dimer, and fibrin/fibrinogen degradation products (FDP) were compared between patients and healthy controls (p<0.001 for all tests). Patients with scrub typhus had longer prothrombin time and lower platelet counts than the controls. Major bleeding was observed in 18/365 patients with scrub typhus. Fifty-one (14.0%) patients presented with severe complications of scrub typhus. Overt DIC and thrombocytopenia (<100,000 platelets/mm 3 ) were observed more frequently in patients with bleeding and severe illness. Furthermore, median platelet counts were low in both groups. Approximately 2.7% (n=10) and 16.4% (n=60) patients with scrub typhus had overt DIC, as defined by the International Society on Thrombosis and Hemostasis DIC score (DIC1) and the DIC-scoring template with a fibrinogen/C-reactive protein-ratio (DIC2), respectively. Three (16.7%) and 10 (55.6%) patients with bleeding had overt DIC, as defined by the DIC1 and DIC2, respectively. Seven (13.7%) and 26 (51%) patients with severe illness had overt DIC, as defined by DIC1 and DIC2, respectively. In conclusion, activation of the coagulation system is an important feature of scrub typhus and is correlated with severe disease, including bleeding. This is the first study to report a relationship between DIC and scrub typhus. Copyright © 2017 Elsevier Inc. All rights reserved.

Survey of flue gas desulfurization systems: Duck Creek Station, Central Illinois Light Co. Final report, Jul-Dec 1978

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laseke, B.A. Jr.

The report presents the results of a survey of operational flue gas desulfurization (FGD) systems on coal-fired utility boilers in the United States. The FGD system installed on Unit 1 at the Duck Creek Station of Central Illinois Light Company is described in terms of design and performance. The system consists of four parallel, wet-limestone, rod-deck scrubber modules designed for 25% capacity each, providing a total sulfur dioxide removal efficiency of 85%. The bottom ash, fly ash, and scrubbing wastes are disposed of in a sludge pond lined with a natural impermeable material. The first module of this four modulemore » FGD system was placed in service on July 1, 1976, and operated intermittently throughout the remainder of the year and for approximately one month in early 1977. On July 23, 1978, the three remaining modules were completed and all four modules were placed in the gas path for treatment of high sulfur flue gas.« less

High Temperature Electrolysis Pressurized Experiment Design, Operation, and Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

J.E. O'Brien; X. Zhang; G.K. Housley

2012-09-01

A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate planar cells with dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. It is also suitable for testing other cell and stack geometries including tubular cells.more » The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. Pressurized operation of a ten-cell internally manifolded solid oxide electrolysis stack has been successfully demonstrated up 1.5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this report. Results of initial testing showed the expected increase in open-cell voltage associated with elevated pressure. However, stack performance in terms of area-specific resistance was enhanced at elevated pressure due to better gas diffusion through the porous electrodes of the cells. Some issues such as cracked cells and seals were encountered during testing. Full resolution of these issues will require additional testing to identify the optimum test configurations and protocols.« less

Method of preparing a dimensionally stable electrode for use in a molten carbonate fuel cell

DOEpatents

Swarr, T.E.; Wnuck, W.G.

1986-01-29

A method is disclosed for preparing a dimensionally stable electrode structure, particularly nickel-chromium anodes, for use in a molten carbonate fuel cell stack. A low-chromium to nickel alloy is provided and oxidized in a mildly oxidizing gas of sufficient oxidation potential to oxidize chromium in the alloy structure. Typically, a steam/H/sub 2/ gas mixture in a ratio of about 100/1 and at a temperature below 800/sup 0/C is used as the oxidizing medium. This method permits the use of less than 5 wt % chromium in nickel alloy electrodes while obtaining good resistance to creep in the electrodes of a fuel cell stack.

Method of preparing a dimensionally stable electrode for use in a MCFC

DOEpatents

Swarr, Thomas E.; Wnuck, Wayne G.

1987-12-22

A method is disclosed for preparing a dimensionally stable electrode structure, particularly nickel-chromium anodes, for use in a molten carbonate fuel cell stack. A low-chromium to nickel alloy is provided and oxidized in a mildly oxidizing gas of sufficient oxidation potential to oxidize chromium in the alloy structure. Typically, a steam/H.sub.2 gas mixture in a ratio of about 100/1 and at a temperature below 800.degree. C. is used as the oxidizing medium. This method permits the use of less than 5 weight percent chromium in nickel alloy electrodes while obtaining good resistance to creep in the electrodes of a fuel cell stack.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

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

Experimental Determination of Exhaust Gas Thrust, Special Report

NASA Technical Reports Server (NTRS)

Pinkel, Benjamin; Voss, Fred

1940-01-01

This investigation presents the results of tests made on a radial engine to determine the thrust that can be obtained from the exhaust gas when discharged from separate stacks and when discharged from the collector ring with various discharge nozzles. The engine was provided with a propeller to absorb the power and was mounted on a test stand equipped with scales for measuring the thrust and engine torque. The results indicate that at full open throttle at sea level, for the engine tested, a gain in thrust horsepower of 18 percent using separate stacks, and 9.5 percent using a collector ring and discharge nozzle, can be expected at an air speed of 550 miles per hour.

Evaluation of nitrous oxide as a substitute for sulfur hexafluoride to reduce global warming impacts of ANSI/HPS N13.1 gaseous uniformity testing

DOE PAGES

Yu, Xiao-Ying; Barnett, J. Matthew; Amidan, Brett G.; ...

2017-12-12

The ANSI/HPS N13.1–2011 standard requires gaseous tracer uniformity testing for sampling associated with stacks used in radioactive air emissions. Sulfur hexafluoride (SF 6), a greenhouse gas with a high global warming potential, has long been the gas tracer used in such testing. To reduce the impact of gas tracer tests on the environment, nitrous oxide (N 2O) was evaluated as a potential replacement to SF 6. The physical evaluation included the development of a test plan to record percent coefficient of variance and the percent maximum deviation between the two gases while considering variables such as fan configuration, injection position,more » and flow rate. Statistical power was calculated to determine how many sample sets were needed, and computational fluid dynamic modeling was utilized to estimate overall mixing in stacks. Results show there are no significant differences between the behaviors of the two gases, and SF 6 modeling corroborated N 2O test results. Although, in principle, all tracer gases should behave in an identical manner for measuring mixing within a stack, the series of physical tests guided by statistics was performed to demonstrate the equivalence of N 2O testing to SF 6 testing in the context of stack qualification tests. In conclusion, the results demonstrate that N 2O is a viable choice leading to a four times reduction in global warming impacts for future similar compliance driven testing.« less

Evaluation of nitrous oxide as a substitute for sulfur hexafluoride to reduce global warming impacts of ANSI/HPS N13.1 gaseous uniformity testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Xiao-Ying; Barnett, J. Matthew; Amidan, Brett G.

The ANSI/HPS N13.1–2011 standard requires gaseous tracer uniformity testing for sampling associated with stacks used in radioactive air emissions. Sulfur hexafluoride (SF 6), a greenhouse gas with a high global warming potential, has long been the gas tracer used in such testing. To reduce the impact of gas tracer tests on the environment, nitrous oxide (N 2O) was evaluated as a potential replacement to SF 6. The physical evaluation included the development of a test plan to record percent coefficient of variance and the percent maximum deviation between the two gases while considering variables such as fan configuration, injection position,more » and flow rate. Statistical power was calculated to determine how many sample sets were needed, and computational fluid dynamic modeling was utilized to estimate overall mixing in stacks. Results show there are no significant differences between the behaviors of the two gases, and SF 6 modeling corroborated N 2O test results. Although, in principle, all tracer gases should behave in an identical manner for measuring mixing within a stack, the series of physical tests guided by statistics was performed to demonstrate the equivalence of N 2O testing to SF 6 testing in the context of stack qualification tests. In conclusion, the results demonstrate that N 2O is a viable choice leading to a four times reduction in global warming impacts for future similar compliance driven testing.« less

SHAWNEE LIME/LIMESTONE SCRUBBING COMPUTERIZED DESIGN/COST-ESTIMATE MODEL USERS MANUAL

EPA Science Inventory

The manual gives a general description of the Shawnee lime/limestone scrubbing computerized design/cost-estimate model and detailed procedures for using it. It describes all inputs and outputs, along with available options. The model, based on Shawnee Test Facility scrubbing data...

40 CFR 264.345 - Operating requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... variations in the physical or chemical properties of the waste feed which will not affect compliance with the... (CO) level in the stack exhaust gas; (2) Waste feed rate; (3) Combustion temperature; (4) An appropriate indicator of combustion gas velocity; (5) Allowable variations in incinerator system design or...

[Epidemiology of scrub typhus and influencing factors in Yunnan province, 2006-2013].

PubMed

Sun, Y; Shi, C; Li, X L; Fang, L Q; Cao, W C

2018-01-10

Objective: To understand the epidemiological characteristics of scrub typhu s and influencing factors in Yunnan province, and provide further information for the prevention and control of scrub typhus. Methods: Based on the incidence data of scrub typhus reported in Yunnan from 2006 to 2013, the epidemiological characteristics of scrub typhus were analyzed and related environmental factors were identified with panel negative binomial regression model. Results: A total of 8 980 scrub typhus cases were reported during 2006-2013 in Yunnan. The average annual incidence was 2.46/100 000, with an uptrend observed. Natural focus expansion was found, affecting 71.3% of the counties in 2013. The epidemic mainly occurred in summer and autumn with the incidence peak during July-October. The annual incidence was higher in females than in males. More cases occurred in children and farmers, the proportions of cases in farmers and pre-school aged children showed an obvious increase. Panel negative binomial regression model indicated that the transmission risk of scrub typhus was positive associated with monthly temperature and monthly relative humidity. Furthermore, an "U" pattern between the risk and the increased coverage of cropland and grassland as well as an "inverted-U" pattern between the risk and increased coverage of shrub were observed. Conclusion: It is necessary to strengthen the scrub typhus surveillance in warm and moist areas as well as the areas with high coverage of cropland and grassland in Yunnan, and the health education in children and farmers who are at high risk.

Predictors of Severity in Pediatric Scrub Typhus.

PubMed

Narayanasamy, Dinesh Kumar; Arun Babu, Thirunavukkarasu; Vijayadevagaran, Vijayasankar; Kittu, Devi; Ananthakrishnan, Shanthi

2018-01-24

To identify the factors that can predict the severity of scrub typhus in children. This prospective study was conducted at a tertiary care teaching hospital between November 2014 to October 2016. All children <12y of age admitted with fever for more than 7d and positive IgM ELISA for scrub typhus were included in the study. These children were followed during the hospital course and their laboratory results, response to treatment and complications were documented. Cases of 'severe scrub typhus' were identified based on criteria from published adult and pediatric studies. Out of 930 children with fever for more than 7d, IgM ELISA for scrub typhus was positive in 230 children. Ninety one (40.6%) cases fulfilled the criteria of 'severe scrub typhus' in children. Out of 45 factors, 27 potential factors were studied. The multivariate analysis identified 5 factors, breathlessness (OR: 6.85, 95%CI: 2.69 to 9.87), altered sensorium (OR: 11.48, 95% CI 3.43 to 10.19), leucocytosis (OR: 3.38, 95% CI 1.12 to 10.16), hypoalbuminemia (OR: 10.78, 95% CI 2.66 to 48.76), and hyponatremia (OR: 10.08, 95% CI 2.11 to 23.42) to be significantly associated with the 'severe scrub typhus' cases. Breathlessness, altered sensorium, leucocytosis, hypoalbuminemia, and hyponatremia predict severity in childhood scrub typhus. Presence of these factors should alert the treating physician regarding the need for intensive monitoring, treatment or referral.

Processing of aerosol particles within the Habshan pollution plume

NASA Astrophysics Data System (ADS)

Semeniuk, T. A.; Bruintjes, R.; Salazar, V.; Breed, D.; Jensen, T.; Buseck, P. R.

2015-03-01

The Habshan industrial site in the United Arab Emirates produces a regional-scale pollution plume associated with oil and gas processing, discharging high loadings of sulfates and chlorides into the atmosphere, which interact with the ambient aerosol population. Aerosol particles and trace gas chemistry at this site were studied on two flights in the summer of 2002. Measurements were collected along vertical plume profiles to show changes associated with atmospheric processing of particle and gas components. Close to the outlet stack, particle concentrations were over 10,000 cm-3, dropping to <2000 cm-3 in more dilute plume around 1500 m above the stack. Particles collected close to the stack and within the dilute plume were individually measured for size, morphology, composition, and mixing state using transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy. Close to the stack, most coarse particles consisted of mineral dust and NaCl crystals from burning oil brines, while sulfate droplets dominated the fine mode. In more dilute plume, at least 1500 m above the stack, the particle spectrum was more diverse, with a significant increase in internally mixed particle types. Dilute plume samples consisted of coarse NaCl/silicate aggregates or NaCl-rich droplets, often with a sulfate component, while fine-fraction particles were of mixed cation sulfates, also internally mixed with nanospherical soot or silicates. Thus, both chloride and sulfate components of the pollution plume rapidly reacted with ambient mineral dust to form coated and aggregate particles, enhancing particle size, hygroscopicity, and reactivity of the coarse mode. The fine-fraction sulfate-bearing particles formed in the plume contribute to regional transport of sulfates, while coarse sulfate-bearing fractions locally reduced the SO2 loading through sedimentation. The chloride- and sulfate-bearing internally mixed particles formed in the plume markedly changed the reflectivity and scattering properties of the ambient aerosol population, as well as its hygroscopic and ice nucleation properties.

Hydrogen gas relief valve

DOEpatents

Whittlesey, Curtis C.

1985-01-01

An improved battery stack design for an electrochemical system having at least one cell from which a gas is generated and an electrolyte in communication with the cell is described. The improved battery stack design features means for defining a substantially closed compartment for containing the battery cells and at least a portion of the electrolyte for the system, and means in association with the compartment means for selectively venting gas from the interior of the compartment means in response to the level of the electrolyte within the compartment means. The venting means includes a relief valve having a float member which is actuated in response to the level of the electrolyte within the compartment means. This float member is adapted to close the relief valve when the level of the electrolyte is above a predetermined level and open the relief valve when the level of electrolyte is below this predetermined level.

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. L. Abbott; K. N. Keck; R. E. Schindler

This screening level risk assessment evaluates potential adverse human health and ecological impacts resulting from continued operations of the calciner at the New Waste Calcining Facility (NWCF) at the Idaho Nuclear Technology and Engineering Center (INTEC), Idaho National Engineering and Environmental Laboratory (INEEL). The assessment was conducted in accordance with the Environmental Protection Agency (EPA) report, Guidance for Performing Screening Level Risk Analyses at Combustion Facilities Burning Hazardous Waste. This screening guidance is intended to give a conservative estimate of the potential risks to determine whether a more refined assessment is warranted. The NWCF uses a fluidized-bed combustor to solidifymore » (calcine) liquid radioactive mixed waste from the INTEC Tank Farm facility. Calciner off volatilized metal species, trace organic compounds, and low-levels of radionuclides. Conservative stack emission rates were calculated based on maximum waste solution feed samples, conservative assumptions for off gas partitioning of metals and organics, stack gas sampling for mercury, and conservative measurements of contaminant removal (decontamination factors) in the off gas treatment system. Stack emissions were modeled using the ISC3 air dispersion model to predict maximum particulate and vapor air concentrations and ground deposition rates. Results demonstrate that NWCF emissions calculated from best-available process knowledge would result in maximum onsite and offsite health and ecological impacts that are less then EPA-established criteria for operation of a combustion facility.« less

KEY COMPARISON Final report on international comparison CCQM-K71: Measurement of stack gas

NASA Astrophysics Data System (ADS)

Nieuwenkamp, G.; van der Veen, A. M. H.; Wessel, R. M.; Qiao, Han; Oh, Sang-Hyub; Kim, Byung-Moon; Kim, Kwang-Sub; Pérez Castorena, Alejandro; Ramírez Nambo, Carlos; Koelliker Delgado, Jorge; Serrano Caballero, Victor M.; Rangel Murillo, Francisco; Avila Salas, Manuel de Jesus; Dias, Florbela; Baptista, Gonçalo; Konopelko, L. A.; Kustikov, Y. A.; Pankratov, V. V.; Selyukov, D. N.; Balandovich, V. S.; Vishnyakov, I. M.; Pavlov, M. V.; Maltsev, M. A.; Botha, Angelique; Valkova, Miroslava; Stovcik, Viliam; Musil, Stanislav; Milton, M. J. T.; Uprichard, I. J.; Vargha, G. M.; Guenther, F.; Gameson, L.; da Cunha, V.

2010-01-01

Industrial stack gas emission measurements are important for process control, control of air pollution, and for implementing legislation regarding carbon dioxide emission rights. Measurements are typically performed using a range of process analysers for carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2) and miscellaneous hydrocarbons. The calibration of these analysers is often performed using a series of binary mixtures of each component in nitrogen. For reasons of efficiency as well as a better match with true stack gas, the use of multi-component mixtures for this purpose would be preferred. The aim of this key comparison is to evaluate the measurement capabilities of national metrology institutes for carbon monoxide, carbon dioxide, nitrogen monoxide, sulphur dioxide and propane in nitrogen. Ten laboratories participated in the key comparison and one in the associated study. The key comparison reference value is based on the gravimetric preparation data. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Edge functionalised & Li-intercalated 555-777 defective bilayer graphene for the adsorption of CO2 and H2O

NASA Astrophysics Data System (ADS)

Lalitha, Murugan; Lakshmipathi, Senthilkumar; Bhatia, Suresh K.

2017-04-01

The adsorption of CO2 and H2O on divacanacy (DV) defected graphene cluster, and its bilayer counterpart is investigated using first-principles calculations. Both single and bilayer DV graphene cluster, are functionalised with H and F atoms. On these sheets the gas molecules are physisorbed, and the divacancy defect effectively improves the adsorption of CO2, while fluorination enhances the hydrophobicity of the graphene cluster. Among the convex and concave curvature regions induced due to the DV defect, the adsorption of the gas molecules on the concave meniscus is more favourable. Fluorine termination induces 73% reduction in Henry law constants for H2O, while for the CO2 molecule it increases by 8%, which indicates the DV defective sheet is a better candidate for CO2 capture compared to the STW defective sheet. Besides, both AA and AB divacant defect bilayer sheets are equally stable, wherein AA stacking results in a cavity between the sheets, while in AB stacking, the layers slide one over the other. Nevertheless, both these bilayer sheets are comparatively stabler than the monolayer. However, intercalation of lithium decreases the interlayer separation, particularly in AA stacking, which enhances the CO2 adsorption, but in the Bernal stacking enhances it hydrophobicity.

Low level vapor verification of monomethyl hydrazine

NASA Technical Reports Server (NTRS)

Mehta, Narinder

1990-01-01

The vapor scrubbing system and the coulometric test procedure for the low level vapor verification of monomethyl hydrazine (MMH) are evaluated. Experimental data on precision, efficiency of the scrubbing liquid, instrument response, detection and reliable quantitation limits, stability of the vapor scrubbed solution, and interference were obtained to assess the applicability of the method for the low ppb level detection of the analyte vapor in air. The results indicated that the analyte vapor scrubbing system and the coulometric test procedure can be utilized for the quantitative detection of low ppb level vapor of MMH in air.

Scrub typhus in the northern provinces of Vietnam: an observational study of admissions to a national referral hospital.

PubMed

Nadjm, Behzad; Thuy, Pham T; Trang, Van D; Ha, Le Dang; Kinh, Nguyen V; Wertheim, Heiman F

2014-11-01

Scrub typhus is a common cause of fever in parts of South East and Southern Asia. Little is known about the disease burden in Vietnam. A 2-year observational study of scrub typhus at a tertiary referral hospital in northern Vietnam was carried out. Diagnosis was based on a single serological test in patients with suggestive clinical symptoms. Scrub typhus was diagnosed in 3.5% (251/7226) of admissions. Cases occurred throughout the year, with incidence highest in the summer. Although complications were common, mortality was low (1.2%; 3/251). These data suggest that scrub typhus is common, with a seasonal distribution in northern Vietnam. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

Large scale database scrubbing using object oriented software components.

PubMed

Herting, R L; Barnes, M R

1998-01-01

Now that case managers, quality improvement teams, and researchers use medical databases extensively, the ability to share and disseminate such databases while maintaining patient confidentiality is paramount. A process called scrubbing addresses this problem by removing personally identifying information while keeping the integrity of the medical information intact. Scrubbing entire databases, containing multiple tables, requires that the implicit relationships between data elements in different tables of the database be maintained. To address this issue we developed DBScrub, a Java program that interfaces with any JDBC compliant database and scrubs the database while maintaining the implicit relationships within it. DBScrub uses a small number of highly configurable object-oriented software components to carry out the scrubbing. We describe the structure of these software components and how they maintain the implicit relationships within the database.

A review of the global epidemiology of scrub typhus.

PubMed

Xu, Guang; Walker, David H; Jupiter, Daniel; Melby, Peter C; Arcari, Christine M

2017-11-01

Scrub typhus is a serious public health problem in the Asia-Pacific area. It threatens one billion people globally, and causes illness in one million people each year. Caused by Orientia tsutsugamushi, scrub typhus can result in severe multiorgan failure with a case fatality rate up to 70% without appropriate treatment. The antigenic heterogeneity of O. tsutsugamushi precludes generic immunity and allows reinfection. As a neglected disease, there is still a large gap in our knowledge of the disease, as evidenced by the sporadic epidemiologic data and other related public health information regarding scrub typhus in its endemic areas. Our objective is to provide a systematic analysis of current epidemiology, prevention and control of scrub typhus in its long-standing endemic areas and recently recognized foci of infection.

A review of the global epidemiology of scrub typhus

PubMed Central

Xu, Guang; Jupiter, Daniel; Melby, Peter C.; Arcari, Christine M.

2017-01-01

Scrub typhus is a serious public health problem in the Asia-Pacific area. It threatens one billion people globally, and causes illness in one million people each year. Caused by Orientia tsutsugamushi, scrub typhus can result in severe multiorgan failure with a case fatality rate up to 70% without appropriate treatment. The antigenic heterogeneity of O. tsutsugamushi precludes generic immunity and allows reinfection. As a neglected disease, there is still a large gap in our knowledge of the disease, as evidenced by the sporadic epidemiologic data and other related public health information regarding scrub typhus in its endemic areas. Our objective is to provide a systematic analysis of current epidemiology, prevention and control of scrub typhus in its long-standing endemic areas and recently recognized foci of infection. PMID:29099844

Comparison of Scrub Typhus Meningitis with Acute Bacterial Meningitis and Tuberculous Meningitis.

PubMed

Kakarlapudi, Svas Raju; Chacko, Anila; Samuel, Prasanna; Verghese, Valsan Philip; Rose, Winsley

2018-01-15

To compare scrub typhus meningitis with bacterial and tuberculous meningitis. Children aged <15 years admitted with meningitis were screened and those who fit criteria for diagnosis of scrub typhus meningitis (n=48), bacterial meningitis (n=44) and tuberculous meningitis (n=31) were included for analysis. Clinical features, investigations and outcomes were compared between the three types of meningitis. Mean age, duration of fever at presentation, presence of headache and, altered sensorium and presence of hepatomegaly/splenomegaly were statistically significantly different between the groups. Scrub typhus had statistically significant thrombocytopenia, shorter hospital stay and a better neurological and mortality outcome. Sub-acute presentation of meningitis in older age group children, and good outcome is associated with scrub typhus when compared to bacterial and tuberculous meningitis.

Epidemiology of scrub typhus and the eschars patterns in South Korea from 2008 to 2012.

PubMed

Park, Ji-Hyuk; Kim, Sun-Ja; Youn, Seung-Ki; Park, Kisoo; Gwack, Jin

2014-01-01

In South Korea, scrub typhus is the most common acute febrile illness in autumn. We analyzed scrub typhus cases reported from 2008 to 2012 to describe the epidemiology of scrub typhus as well as eschar patterns. A total of 30,478 cases were reported from 2008 to 2012; the incidence rates were higher in the southern and western regions of South Korea. The common clinical symptoms of confirmed scrub typhus cases from 2010 to 2012 were fever/chills (95.2%), eschars (78.9%), and myalgia (61.7%). The primary sites of eschars were the lower extremities (19.0%), abdomen/waist (13.4%), and axilla (11.5%) in men and the shoulder/frontal chest (15.1%), lower extremities (14.5%), and abdomen/waist (13.6%) in women. Regardless of gender, eschars tended to be more on the lower extremities among the leisure activities group. Among the occupational farm work group, who usually lived in rural areas, eschars appeared most frequently on the abdomen/waist in men and on the shoulder/frontal chest in women. Eschar patterns were influenced by gender and activities. These results could facilitate the prevention of scrub typhus and clarify the current status of scrub typhus in South Korea.

Etiologies of Acute Undifferentiated Fever and Clinical Prediction of Scrub Typhus in a Non-Tropical Endemic Area

PubMed Central

Jung, Ho-Chul; Chon, Sung-Bin; Oh, Won Sup; Lee, Dong-Hyun; Lee, Ho-Jin

2015-01-01

Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960–0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0–98.1%) and 90.9% (86.0–94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule. PMID:25448236

Activation, Impaired Tumor Necrosis Factor-α Production, and Deficiency of Circulating Mucosal-Associated Invariant T Cells in Patients with Scrub Typhus.

PubMed

Kang, Seung-Ji; Jin, Hye-Mi; Won, Eun Jeong; Cho, Young-Nan; Jung, Hyun-Ju; Kwon, Yong-Soo; Kee, Hae Jin; Ju, Jae Kyun; Kim, Jung-Chul; Kim, Uh Jin; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook

2016-07-01

Mucosal-associated invariant T (MAIT) cells contribute to protection against certain microorganism infections. However, little is known about the role of MAIT cells in Orientia tsutsugamushi infection. Hence, the aims of this study were to examine the level and function of MAIT cells in patients with scrub typhus and to evaluate the clinical relevance of MAIT cell levels. Thirty-eight patients with scrub typhus and 53 health control subjects were enrolled in the study. The patients were further divided into subgroups according to disease severity. MAIT cell level and function in the peripheral blood were measured by flow cytometry. Circulating MAIT cell levels were found to be significantly reduced in scrub typhus patients. MAIT cell deficiency reflects a variety of clinical conditions. In particular, MAT cell levels reflect disease severity. MAIT cells in scrub typhus patients displayed impaired tumor necrosis factor (TNF)-α production, which was restored during the remission phase. In addition, the impaired production of TNF-α by MAIT cells was associated with elevated CD69 expression. This study shows that circulating MAIT cells are activated, numerically deficient, and functionally impaired in TNF-α production in patients with scrub typhus. These abnormalities possibly contribute to immune system dysregulation in scrub typhus infection.

Concept-match medical data scrubbing. How pathology text can be used in research.

PubMed

Berman, Jules J

2003-06-01

In the normal course of activity, pathologists create and archive immense data sets of scientifically valuable information. Researchers need pathology-based data sets, annotated with clinical information and linked to archived tissues, to discover and validate new diagnostic tests and therapies. Pathology records can be used for research purposes (without obtaining informed patient consent for each use of each record), provided the data are rendered harmless. Large data sets can be made harmless through 3 computational steps: (1) deidentification, the removal or modification of data fields that can be used to identify a patient (name, social security number, etc); (2) rendering the data ambiguous, ensuring that every data record in a public data set has a nonunique set of characterizing data; and (3) data scrubbing, the removal or transformation of words in free text that can be used to identify persons or that contain information that is incriminating or otherwise private. This article addresses the problem of data scrubbing. To design and implement a general algorithm that scrubs pathology free text, removing all identifying or private information. The Concept-Match algorithm steps through confidential text. When a medical term matching a standard nomenclature term is encountered, the term is replaced by a nomenclature code and a synonym for the original term. When a high-frequency "stop" word, such as a, an, the, or for, is encountered, it is left in place. When any other word is encountered, it is blocked and replaced by asterisks. This produces a scrubbed text. An open-source implementation of the algorithm is freely available. The Concept-Match scrub method transformed pathology free text into scrubbed output that preserved the sense of the original sentences, while it blocked terms that did not match terms found in the Unified Medical Language System (UMLS). The scrubbed product is safe, in the restricted sense that the output retains only standard medical terms. The software implementation scrubbed more than half a million surgical pathology report phrases in less than an hour. Computerized scrubbing can render the textual portion of a pathology report harmless for research purposes. Scrubbing and deidentification methods allow pathologists to create and use large pathology databases to conduct medical research.

Coal-Fired Boilers at Navy Bases, Navy Energy Guidance Study, Phase II and III.

DTIC Science & Technology

1979-05-01

several sizes were performed. Central plants containing four equal-sized boilers and central flue gas desulfurization facilities were shown to be less...Conceptual design and parametric cost studies of steam and power generation systems using coal-fired stoker boilers and stack gas scrubbers in

DETECTION OF MERCURIC BROMIDE IN A GAS PHASE FLOW CELL BY LASER PHOTOFRAGMENT FLUORESCENCE SPECTROSCOPY. (R825380)

EPA Science Inventory

Photofragment fluorescence (PFF) spectroscopy offers real-time monitoring
capability with high-analytical sensitivity and selectivity for volatile mercury
compounds found in process gas streams, such as incinerator stacks. In this
work, low concentrations (6 ppb to...

Study on component interface evolution of a solid oxide fuel cell stack after long term operation

NASA Astrophysics Data System (ADS)

Yang, Jiajun; Huang, Wei; Wang, Xiaochun; Li, Jun; Yan, Dong; Pu, Jian; Chi, Bo; Li, Jian

2018-05-01

A 5-cell solid oxide fuel cell (SOFC) stack with external manifold structure is assembled and underwent a durability test with an output of 250 W for nearly 4400 h when current density and operating temperature are 355 mA/cm2 and 750 °C. Cells used in the stack are anode-supported cells (ASC) with yttria-stabilized zirconia (YSZ) electrolytes, Ni/YSZ hydrogen electrodes, and YSZ based composite cathode. The dimension of the cell is 150 × 150 mm (active area: 130 × 130 mm). Ceramic-glass sealant is used in the stack to keep the gas tightness between cells, interconnects and manifolds. Pure hydrogen and dry air are used as fuel and oxidant respectively. The stack has a maximum output of 340 W at 562 mA/cm2 current density at 750 °C. The stack shows a degradation of 1.5% per 1000 h during the test with 2 thermal cycles to room temperature. After the test, the stack was dissembled and examined. The relationship between microstructure changes of interfaces and degradation in the stack are discussed. The microstructure evolution of interfaces between electrode, contact material and current collector are unveiled and their relationship with the degradation is discussed.

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

DOEpatents

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

1998-04-21

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

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

DOEpatents

Gillett, James E.; Dederer, Jeffrey T.; Zafred, Paolo R.; Collie, Jeffrey C.

1998-01-01

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

ETR COMPLEX. CAMERA FACING EAST. FROM LEFT TO RIGHT: ETRCRITICAL ...

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

ETR COMPLEX. CAMERA FACING EAST. FROM LEFT TO RIGHT: ETR-CRITICAL FACILITY BUILDING, ETR CONTROL BUILDING (ATTACHED TO HIGH-BAY ETR), ETR, ONE-STORY SECTION OF ETR BUILDING, ELECTRICAL BUILDING, COOLING TOWER PUMP HOUSE, COOLING TOWER. COMPRESSOR AND HEAT EXCHANGER BUILDING ARE PARTLY IN VIEW ABOVE ETR. DARK-COLORED DUCTS PROCEED FROM GROUND CONNECTION TO ETR WASTE GAS STACK. OTHER STACK IS MTR STACK WITH FAN HOUSE IN FRONT OF IT. RECTANGULAR STRUCTURE NEAR TOP OF VIEW IS SETTLING BASIN. INL NEGATIVE NO. 56-4102. Unknown Photographer, ca. 1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Enclosed ground-flare incinerator

DOEpatents

Wiseman, Thomas R.

2000-01-01

An improved ground flare is provided comprising a stack, two or more burner assemblies, and a servicing port so that some of the burner assemblies can be serviced while others remain in operation. The burner assemblies comprise a burner conduit and nozzles which are individually fitted to the stack's burner chamber and are each removably supported in the chamber. Each burner conduit is sealed to and sandwiched between a waste gas inlet port and a matching a closure port on the other side of the stack. The closure port can be opened for physically releasing the burner conduit and supplying sufficient axial movement room for extracting the conduit from the socket, thereby releasing the conduit for hand removal through a servicing port. Preferably, the lower end of the stack is formed of one or more axially displaced lower tubular shells which are concentrically spaced for forming annular inlets for admitting combustion air. An upper tubular exhaust stack, similarly formed, admits additional combustion air for increasing the efficiency of combustion, increasing the flow of exhausted for improved atmospheric dispersion and for cooling the upper stack.

Cleaning By Blasting With Pellets Of Dry Ice

NASA Technical Reports Server (NTRS)

Fody, Jody

1993-01-01

Dry process strips protective surface coats from parts to be cleaned, without manual scrubbing. Does not involve use of flammable or toxic solvents. Used to remove coats from variety of materials, including plastics, ceramics, ferrous and nonferrous metals, and composites. Adds no chemical-pollution problem to problem of disposal of residue of coating material. Process consists of blasting solid carbon dioxide (dry ice) pellets at surface to be cleaned. Pellets sublime on impact and pass into atmosphere as carbon dioxide gas. Size, harness, velocity, and quantity of pellets adjusted to suit coating material and substrate.

Avagard hand antisepsis vs. traditional scrub in 3600 pediatric urologic procedures.

PubMed

Weight, Christopher J; Lee, Michael C; Palmer, Jeffrey S

2010-07-01

Avagard is a waterless, scrubless, and brushless hand antiseptic approved by the Food and Drug Administration as a replacement for traditional presurgical brush hand scrubbing. We evaluated the use of Avagard compared with hand brush scrub preparation for inpatient and outpatient pediatric urological operations. We evaluated the first 1800 patients for whom we used Avagard as a preoperative hand antiseptic and compared them with the last 1800 consecutive patients for whom we performed traditional antiseptic-impregnated hand-brush scrubbing. All patients underwent a variety of inpatient and outpatient open, endoscopic, and laparoscopic pediatric urological procedures. Patients were monitored postoperatively for wound infection, and patients and surgeon were monitored for side effects. A cost analysis was performed. The incidence of wound infection was 2/1800 (0.11%) in the Avagard group and 3/1800 (0.17%) in the hand-scrub group (P > .99 Fisher's exact test). All wound infections were successfully treated with a single course of oral antibiotics. No side effects for the patients or surgeon were noted, including skin irritations or allergic reactions in either group. The traditional hand scrub is nearly 2 times more expensive per application than Avagard. The incidence of wound infections in pediatric urological procedures is low (0.09%). We observe that Avagard provides comparable hand antisepsis to the traditional surgical scrub in a variety of pediatric urological procedures. Avagard is superior to the surgical hand scrub in cost-effectiveness and time efficiency. Urologists should consider using Avagard for hand antisepsis before surgery. Copyright 2010 Elsevier Inc. All rights reserved.

Clinical Profile of Scrub Typhus in Pregnancy in Sub-Himalayan Region.

PubMed

Kumar, Ritesh; Thakur, Surinder; Bhawani, Rajesh; Kanga, Anil; Ranjan, Asha

2016-10-01

Scrub typhus is rare in pregnancy, but it has now become an important cause of febrile illness in pregnancy in sub-Himalayan region of India. Only a few case reports have been published so far, and they show adverse maternal and fetal outcomes. No consensus has been reached till now regarding treatment. All the pregnant patients irrespective of period of gestation admitted with febrile illness with positive IgM ELISA for scrub typhus with or without eschar were included. The clinical profile was observed using a detailed history of symptoms, travel, recreation, agricultural activities, treatment record prior to admission, and a detailed examination, and the treatment outcome was noted. Fever workup including cultures, CXR, CSF analysis, serology for scrub was done. IgM scrub typhus was done by kit method manufactured by InBios Intertational, Inc. We observed in total 14 pregnant patients out of which eight were in the the second trimester and six were in the third trimester. The clinical features of the disease observed for pregnant females were the same as for nonpregnant females. There was no difference in the severity of scrub typhus between pregnant and nonpregnant women. No mortality was found in these patients. On follow-up, they had normal peripartum and postpartum periods. All were treated with azithromycin 500 mg once a day for 5 days. Although rare, scrub typhus should be considered in differential diagnosis of fever in pregnant patients especially in scrub season. Azithromycin should be the drug of choice in pregnancy as it has no adverse effect on fetus and pregnancy outcome.

Cytokine network in scrub typhus: high levels of interleukin-8 are associated with disease severity and mortality.

PubMed

Astrup, Elisabeth; Janardhanan, Jeshina; Otterdal, Kari; Ueland, Thor; Prakash, John A J; Lekva, Tove; Strand, Øystein A; Abraham, O C; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M

2014-02-01

Scrub typhus, caused by Orientia tsutsugamushi, is endemic in the Asia-Pacific region. Mortality is high if untreated, and even with treatment as high as 10-20%, further knowledge of the immune response during scrub typhus is needed. The current study was aimed at comparing plasma levels of a variety of inflammatory mediators in scrub typhus patients and controls in South India in order to map the broader cytokine profile and their relation to disease severity and clinical outcome. We examined plasma levels of several cytokines in scrub typhus patients (n = 129) compared to healthy controls (n = 31) and infectious disease controls (n = 31), both in the acute phase and after recovery, by multiplex technology and enzyme immunoassays. Scrub typhus patients were characterized by marked changes in the cytokine network during the acute phase, differing not only from healthy controls but also from infectious disease controls. While most of the inflammatory markers were raised in scrub typhus, platelet-derived mediators such as RANTES were markedly decreased, probably reflecting enhanced platelet activation. Some of the inflammatory markers, including various chemokines (e.g., interleukin-8, monocyte chemoattractant peptide-1 and macrophage inflammatory protein-1β) and downstream markers of inflammation (e.g., C-reactive protein and pentraxin-3), were also associated with disease severity and mortality during follow-up, with a particular strong association with interleukin-8. Our findings suggest that scrub typhus is characterized by a certain cytokine profile that includes dysregulated levels of a wide range of mediators, and that this enhanced inflammation could contribute to disease severity and clinical outcome.

Two decades of change in a coastal scrub community: songbird responses to plant succession

Treesearch

Mary K. Chase; Aaron L. Holmes; Thomas Gardali; Grant Ballard; Geoffrey R. Geupel; Nadav Nur

2005-01-01

Coastal scrub habitats in California are threatened by habitat loss, fragmentation, and degradation. Local and statewide declines have been observed in several birds that breed in coastal scrub, most notably the California Gnatcatcher (Polioptila californica; Atwood 1993), but also include more common species such as the Whitecrowned Sparrow...

Alluvial Scrub Vegetation in Coastal Southern California

Treesearch

Ted L. Hanes; Richard D. Friesen; Kathy Keane

1989-01-01

Certain floodplain systems in southern California sustain a unique scrub vegetation rather than riparian woodlands due to a lack of perennial water. Alluvial scrub occurs on outwash fans and riverine deposits along the coastal side of major mountains of southern California. This vegetation type is adapted to severe floods and erosion, nutrient-poor substrates, and the...

77 FR 77037 - Procurement List; Additions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-31

...-Compatible, 2'' x 8'' NSN: 7920-00-NIB-0545--Scrub Brush, Wire, Knuckle Guard, Long Handle, Ergonomic, 6'' x 1 1/8'', w/built-in scraper NSN: 7920-00-NIB-0547--Scrub Brush, Wire, Stainless, Ergonomic, 5'' NSN: 7920-00-NIB-0558--Scrub Brush, Wire, Black Tempered, Ergonomic, 5'' NSN: 7920-00-NIB-0563--Wire Brush...

The Correlation of Endoscopic Findings and Clinical Features in Korean Patients with Scrub Typhus: A Cohort Study.

PubMed

Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo

2016-01-01

Scrub typhus is an infectious disease caused by Orientia tsutsugamushi-induced systemic vasculitis, but the involvement of the gastrointestinal tract and the endoscopic findings associated with scrub typhus are not well understood. We performed a prospective study and recommend performing esophagogastroduodenoscopy (EGD) for all possible scrub typhus patients, regardless of gastrointestinal symptoms. Gastrointestinal symptoms, endoscopic findings and clinical severity based on organ involvement and ICU admission were analyzed. Gastrointestinal symptoms occurred in up to 76.4% of scrub typhus patients. The major endoscopic findings were ulcers (43/127, 33.9%). Interestingly, 7.1% (9/127) of the patients presented with esophageal candidiasis. There was no correlation between the presence or absence of gastrointestinal symptoms and the endoscopic grade (P = 0.995). However, there was a positive correlation between the clinical severity and the endoscopic findings (P = 0.001). Sixty-three percent of the patients presented with erosion or ulcers on prospectively performed endoscopic evaluations, irrespective of gastrointestinal symptoms. Gastrointestinal symptoms did not reflect the need for endoscopy. Scrub typhus patients could have significant endoscopic abnormalities even in the absence of gastrointestinal symptoms.

Microbiological Evaluation of the Efficacy of Soapy Water to Clean Hands: A Randomized, Non-Inferiority Field Trial

PubMed Central

Amin, Nuhu; Pickering, Amy J.; Ram, Pavani K.; Unicomb, Leanne; Najnin, Nusrat; Homaira, Nusrat; Ashraf, Sania; Abedin, Jaynal; Islam, M. Sirajul; Luby, Stephen P.

2014-01-01

We conducted a randomized, non-inferiority field trial in urban Dhaka, Bangladesh among mothers to compare microbial efficacy of soapy water (30 g powdered detergent in 1.5 L water) with bar soap and water alone. Fieldworkers collected hand rinse samples before and after the following washing regimens: scrubbing with soapy water for 15 and 30 seconds; scrubbing with bar soap for 15 and 30 seconds; and scrubbing with water alone for 15 seconds. Soapy water and bar soap removed thermotolerant coliforms similarly after washing for 15 seconds (mean log10 reduction = 0.7 colony-forming units [CFU], P < 0.001 for soapy water; mean log10 reduction = 0.6 CFU, P = 0.001 for bar soap). Increasing scrubbing time to 30 seconds did not improve removal (P > 0.05). Scrubbing hands with water alone also reduced thermotolerant coliforms (mean log10 reduction = 0.3 CFU, P = 0.046) but was less efficacious than scrubbing hands with soapy water. Soapy water is an inexpensive and microbiologically effective cleansing agent to improve handwashing among households with vulnerable children. PMID:24914003

Effect of Latitude and Seasonal Variation on Scrub Typhus, South Korea, 2001–2013

PubMed Central

Jeung, Ye Sul; Kim, Choon-Mee; Yun, Na Ra; Kim, Seok-Won; Han, Mi Ah; Kim, Dong-Min

2016-01-01

In South Korea, scrub typhus is one of the most common rickettsial diseases. The number of scrub typhus patients has increased in South Korea, a total of 69,210 cases were reported from 2001 to 2013. The seasonality and relation of scrub typhus cases to latitude were analyzed in this article using data obtained from the National Notifiable Diseases Surveillance System website of the Korea Centers for Disease Control and Prevention. The incidence of scrub typhus tended to increase in the later months of the year, especially in October–December. In general, lower latitudes were associated with a later peak incidence. Our results suggest for the first time that the monthly observed incidence tended to increase in the later months of the year as the latitude decreased, and on a yearly basis in Korea. PMID:26503283

Prevalence of scrub typhus in pyrexia of unknown origin and assessment of interleukin-8, tumor necrosis factor-alpha, and interferon-gamma levels in scrub typhus-positive patients.

PubMed

Rizvi, Meher; Sultan, Asfia; Chowdhry, Madhav; Azam, Mohd; Khan, Fatima; Shukla, Indu; Khan, Haris M

2018-01-01

Scrub typhus is lesser known cause of fever of unknown origin in India. Even if there have been reports documenting the prevalence of scrub typhus in different parts of India, it is still an unknown entity, and clinicians usually do not consider it as differential diagnosis. The present study was performed to document the prevalence of scrub typhus among febrile patients in western part of Uttar Pradesh and to assess the clinical profile of infected patients on the one hand and knowledge, attitude, and practices among clinicians on the other. A total of 357 adult patients with fever of more than 5-day duration were recruited. All patients underwent complete physical examination, and detailed clinical history was elicited as per predesigned pro forma. After primary screening to rule out malaria, enteric fever, and leptospirosis infection, secondary screening for scrub typhus was done by rapid screen test and IgM ELISA. Scrub typhus infection was positive in 91 (25.5%) cases. The most common symptoms among the patients were fever (100%), pain in abdomen (79.1%), pedal edema 56 (61.5%), rash 44 (48.3%), headache 44 (48.3%), vomiting 42 (46.1%), constipation 33 (36.2%), cough 28 (30.7%), and lymphadenopathy 20 (21.9%). The median values of interleukin-8, interferon-gamma, and tumor necrosis factor-alpha in healthy controls were 15.54 pg/ml, 7.77 pg/ml, and 54.1 pg/ml, respectively, while the median values of these cytokines in scrub typhus-positive patients were 21.04 pg/ml, 8.74 pg/ml, and 73.8 pg/ml, respectively. Our results highlight that scrub typhus infection is an important cause of pyrexia of unknown origin, and active surveillance is necessary to assess the exact magnitude and distribution of the disease.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lefeuvre, F.E.; Wrolstad, K.H.; Zou, Ke Shan

Total and Unocal estimated sand-shale ratios in gas reservoirs from the upper Tertiary clastics of Myanmar. They separately used deterministic pre-stack and statistical post-stack seismic attribute analysis calibrated at two wells to objectively extrapolate the lithologies and reservoir properties several kilometers away from the wells. The two approaches were then integrated and lead to a unique distribution of the sands and shales in the reservoir which fit in the known regional geological model. For the sands, the fluid distributions (gas and brine) were also estimated as well as the porosity, water saturation, thickness and clay content of the sands. Thismore » was made possible by using precise elastic modeling based on the Biot-Gassmann equation in order to integrate the effects of reservoir properties on seismic signatures.« less

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

NASA Technical Reports Server (NTRS)

Farooque, M.; Maru, H.; Skok, A.

1981-01-01

Two short stacks were pressure tested at 446 kPa (4.4 atm.) and the pressure gains were more than the theoretically predicted gains. Temperature profiles were observed to be independent of operating pressure. The pressure drop was found to be inversely proportional to operating pressure as expected. Continuous pressurized operation of a stack for 1000 hours verified the compatability of the fuel cell component design. A simple pressurization procedure was also developed. Six separate designs, covering two gas cooling schemes (DIGAS and separated) and two cooling channel geometries (straight through and treed), were analysed on the net voltage output basis. Separated cooling with 5 cells per cooler was recognized to be the best among the designs considered.

Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

DTIC Science & Technology

2010-09-01

Korean J Paras/to/. Vol. 48, No. 3: 237-243, September 2010 DOl: JO.J3471kjp.2010.48.J.237 Serosurveillance of Scrub Typhus in Small Mammals...65th Medical BrigadeAJSAMEDDAC-Korea, Unit# 15281, APO AP 96205-5281, USA Abstract: Comprehensive quarterly serosurveillance on scrub typhus in small...rarely observed (prevalence < 1 0%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4

Fuel Cell Power Plant Initiative. Volume 2; Preliminary Design of a Fixed-Base LFP/SOFC Power System

NASA Technical Reports Server (NTRS)

Veyo, S.E.

1997-01-01

This report documents the preliminary design for a military fixed-base power system of 3 MWe nominal capacity using Westinghouse's tubular Solid Oxide Fuel Cell [SOFC] and Haldor Topsoe's logistic fuels processor [LFP]. The LFP provides to the fuel cell a methane rich sulfur free fuel stream derived from either DF-2 diesel fuel, or JP-8 turbine fuel. Fuel cells are electrochemical devices that directly convert the chemical energy contained in fuels such as hydrogen, natural gas, or coal gas into electricity at high efficiency with no intermediate heat engine or dynamo. The SOFC is distinguished from other fuel cell types by its solid state ceramic structure and its high operating temperature, nominally 1000'C. The SOFC pioneered by Westinghouse has a tubular geometry closed at one end. A power generation stack is formed by aggregating many cells in an ordered array. The Westinghouse stack design is distinguished from other fuel cell stacks by the complete absence of high integrity seals between cell elements, cells, and between stack and manifolds. Further, the reformer for natural gas [predominantly methane] and the stack are thermally and hydraulically integrated with no requirement for process water. The technical viability of combining the tubular SOFC and a logistic fuels processor was demonstrated at 27 kWe scale in a test program sponsored by the Advanced Research Projects Agency [ARPA) and carried out at the Southern California Edison's [SCE] Highgrove generating station near San Bernardino, California in 1994/95. The LFP was a breadboard design supplied by Haldor Topsoe, Inc. under subcontract to Westinghouse. The test program was completely successful. The LFP fueled the SOFC for 766 hours on JP-8 and 1555 hours of DF-2. In addition, the fuel cell operated for 3261 hours on pipeline natural gas. Over the 5582 hours of operation, the SOFC generated 118 MVVH of electricity with no perceptible degradation in performance. The LFP processed military specification JP-8 and DF-2 removing the sulfur and reforming these liquid fuels to a methane rich gaseous fuel. Results of this program are documented in a companion report titled 'Final Report-Solid Oxide Fuel Cell/ Logistic Fuels Processor 27 kWe Power System'.

Activation, Impaired Tumor Necrosis Factor-α Production, and Deficiency of Circulating Mucosal-Associated Invariant T Cells in Patients with Scrub Typhus

PubMed Central

Won, Eun Jeong; Cho, Young-Nan; Jung, Hyun-Ju; Kwon, Yong-Soo; Kee, Hae Jin; Ju, Jae Kyun; Kim, Jung-Chul; Kim, Uh Jin; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook

2016-01-01

Background Mucosal-associated invariant T (MAIT) cells contribute to protection against certain microorganism infections. However, little is known about the role of MAIT cells in Orientia tsutsugamushi infection. Hence, the aims of this study were to examine the level and function of MAIT cells in patients with scrub typhus and to evaluate the clinical relevance of MAIT cell levels. Methodology/Principal Findings Thirty-eight patients with scrub typhus and 53 health control subjects were enrolled in the study. The patients were further divided into subgroups according to disease severity. MAIT cell level and function in the peripheral blood were measured by flow cytometry. Circulating MAIT cell levels were found to be significantly reduced in scrub typhus patients. MAIT cell deficiency reflects a variety of clinical conditions. In particular, MAT cell levels reflect disease severity. MAIT cells in scrub typhus patients displayed impaired tumor necrosis factor (TNF)-α production, which was restored during the remission phase. In addition, the impaired production of TNF-α by MAIT cells was associated with elevated CD69 expression. Conclusions This study shows that circulating MAIT cells are activated, numerically deficient, and functionally impaired in TNF-α production in patients with scrub typhus. These abnormalities possibly contribute to immune system dysregulation in scrub typhus infection. PMID:27463223

Scrub Typhus: An Emerging Neglected Tropical Disease in Nepal.

PubMed

Upadhyaya, B P; Shakya, G; Adhikari, S; Rijal, N; Acharya, J; Maharjan, L; Marasini, B R

2016-05-01

Scrub typhus is a neglected tropical disease and is under reported from Nepal. The objective of this study was to investigate the sero-epidemiology of scrub typhus in patients suffering from acute febrile illness. A total of 434 specimens collected from July to November 2015 at National Public Health Laboratory (NPHL) were investigated for detection of immunoglobulin M (IgM) antibody to Orientiatsutsugamushi.The Scrub Typhus Detect TM kit (InBios, USA) was used to detect the antibodies to O.tsutsugamushi in human serum. Randomly selected 10% positive specimens were used for confirmation by dot- enzyme-linked immunosorbent assay and indirect immunofluorescence assay. Of the total, 175 (40.3%) were positive for IgM antibodies to O. tsutsugamushi. Positive results of scrub typhus were highest among female in 11-20 year followed by males in 41-50 years age group. The IgM antibodies to O. tsutusugamushi were positive in specimens of various geographical regions including 30 districts of Nepal. Positive cases were found in various ecological regions of Nepal. Scrub typhus is one of the neglected tropical diseases in Nepal. Patients with acute febrile illness should be investigated for scrub typhus with high priority. There is an urgent need of reliable and affordable diagnostic tests at all level of health facilities of Nepal. Surveillance and public health awareness about the disease transmission and preventive measures needs to be initiated.

Tailor Made Synthesis of T-Shaped and π-STACKED Dimers in the Gas Phase: Concept for Efficient Drug Design and Material Synthesis

NASA Astrophysics Data System (ADS)

Kumar, Sumit; Das, Aloke

2013-06-01

Non-covalent interactions play a key role in governing the specific functional structures of biomolecules as well as materials. Thus molecular level understanding of these intermolecular interactions can help in efficient drug design and material synthesis. It has been found from X-ray crystallography that pure hydrocarbon solids (i.e. benzene, hexaflurobenzene) have mostly slanted T-shaped (herringbone) packing arrangement whereas mixed solid hydrocarbon crystals (i.e. solid formed from mixtures of benzene and hexafluorobenzene) exhibit preferentially parallel displaced (PD) π-stacked arrangement. Gas phase spectroscopy of the dimeric complexes of the building blocks of solid pure benzene and mixed benzene-hexafluorobenzene adducts exhibit similar structural motifs observed in the corresponding crystal strcutures. In this talk, I will discuss about the jet-cooled dimeric complexes of indole with hexafluorobenzene and p-xylene in the gas phase using Resonant two photon ionzation and IR-UV double resonance spectroscopy combined with quantum chemistry calculations. In stead of studying benzene...p-xylene and benzene...hexafluorobenzene dimers, we have studied corresponding indole complexes because N-H group is much more sensitive IR probe compared to C-H group. We have observed that indole...hexafluorobenzene dimer has parallel displaced (PD) π-stacked structure whereas indole...p-xylene has slanted T-shaped structure. We have shown here selective switching of dimeric structure from T-shaped to π-stacked by changing the substituent from electron donating (-CH3) to electron withdrawing group (fluorine) in one of the complexing partners. Thus, our results demonstrate that efficient engineering of the non-covalent interactions can lead to efficient drug design and material synthesis.

Reduction of nitrogen oxides with catalytic acid resistant aluminosilicate molecular sieves and ammonia

DOEpatents

Pence, Dallas T.; Thomas, Thomas R.

1980-01-01

Noxious nitrogen oxides in a waste gas stream such as the stack gas from a fossil-fuel-fired power generation plant or other industrial plant off-gas stream is catalytically reduced to elemental nitrogen and/or innocuous nitrogen oxides employing ammonia as reductant in the presence of a zeolite catalyst in the hydrogen or sodium form having pore openings of about 3 to 10 A.

77 FR 64326 - Procurement List; Proposed Additions and Deletions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-19

...-Compatible, 2'' x 8''. NSN: 7920-00-NIB-0545--Scrub Brush, Wire, Knuckle Guard, Long Handle, Ergonomic, 6'' x 1 1/8'', w/built-in scraper. NSN: 7920-00-NIB-0547--Scrub Brush, Wire, Stainless, Ergonomic, 5''. NSN: 7920-00-NIB-0558--Scrub Brush, Wire, Black Tempered, Ergonomic, 5''. NSN: 7920-00-NIB-0563--Wire...

A Business Case Analysis to Determine the Feasibility of a Scrub Management System at Brooke Army Medical Center

DTIC Science & Technology

2009-03-07

Designated Areas lor Scrub Issue i : FHSI 2. I West ?. Cardiac Cath Lab> 4. Cardiology Radiology 5. Centralized Materiel Services 6. CCUs...Scrub Management System 37 BAMC Memo 52-2 4-. Neiirosnrgciy Clinic 15. Bum Tinuma Unit 46 Cinq Rullis -4". 9J V School -IS. Veterinary Clinic

Steam generation and pollution control system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, D.H.

1979-02-13

The heat and flu gases which are ordinarily expelled through an emission stack of a conventional furnace are instead channeled through a heat exchanger to produce steam for power generation and are subsequently directed through a gas scrubber apparatus to remove all contaminates from the flu gas prior to expelling the gases into atmosphere.

AMMONIA ABSORPTION/AMMONIUM BISULFATE REGENERATION PILOT PLANT FOR FLUE GAS DESULFURIZATION

EPA Science Inventory

The report gives results of a pilot-plant study of the ammonia absorption/ammonium bisulfate regeneration process for removing SO2 from the stack gas of coal-fired power plants. Data were developed on the effects of such operating variable in the absorption of SO2 by ammoniacal l...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Confer, L.; Kramer, K.L.

A condensing type heat exchanger operating at Henkel Corporation's plant in Kankakee, IL, has enabled the plant to save $400,000 in energy costs within the first 22 months of operation, recouping the initial capital investment for the unit within that time frame. The heat exchanger enables the plant to accomplish what historically was considered taboo - to cool boiler stack gas down to 130/sup 0/F, below the dew point, and thus recover both sensible and latent heat from the gas. Traditionally, moisture could not be squeezed out of stack gas below the recommended temperature of 250/sup 0/F because the stackmore » gas close to the heat exchanger tubes would approach the dew point, condense and attack metal surfaces. The condensing type heat exchanger can withstand corrosive conditions, however, because all wetted surfaces on the flue side of the shell and copper-nickel tube design are protected with an extruded Teflon fluorocarbon resin covering (not coating). The waste heat recovery system was installed over a two-month period in 1985. Performance has been above expectations with greater energy savings than originally projected. The amount of operator attention required is minimal.« less

75 FR 33391 - Amendments to the Protocol Gas Verification Program and Minimum Competency Requirements for Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-11

...Recent EPA gas audit results indicate that some gas cylinders used to calibrate continuous emission monitoring systems on stationary sources do not meet EPA's performance specification. Reviews of stack test reports in recent years indicate that some stack testers do not properly follow EPA test methods or do not correctly calculate test method results. Therefore, EPA is proposing to amend its Protocol Gas Verification Program (PGVP) and the minimum competency requirements for air emission testing (formerly air emission testing body requirements) to improve the accuracy of emissions data. EPA is also proposing to amend other sections of the Acid Rain Program continuous emission monitoring system regulations by adding and clarifying certain recordkeeping and reporting requirements, removing the provisions pertaining to mercury monitoring and reporting, removing certain requirements associated with a class-approved alternative monitoring system, disallowing the use of a particular quality assurance option in EPA Reference Method 7E, adding an incorporation by reference that was inadvertently left out of the January 24, 2008 final rule, and clarifying the language and applicability of certain provisions.

Stature of sub-arctic birch in relation to growth rate, lifespan and tree form.

PubMed

Jónsson, Thorbergur Hjalti

2004-11-01

Sub-arctic mountain birch Betula pubescens var. pumila communities in the North Atlantic region are of variable stature, ranging from prostrate scrubs to forests with trees up to 12 m high. Four hypotheses were tested, relating growth and population characteristics of sub-arctic birch woodland and scrub to tree stature; i.e. the variable stature of birch woods is due to differences in (1) the mean growth rate; (2) the age-related patterns of growth rate; (3) the life expectancy of stems; or (4) the tree form. A stratified random sample of 300 birch trees was drawn from the total population of indigenous birch woodlands and scrub in Iceland, yielding 286 valid sample genets. The population was divided into three sub-populations with dominant trees 0-2, 2-4 and 4-12 m tall, referred to as birch scrub, birch scrub-woodland and birch forest, respectively. Trees in the scrub population were of more contorted growth form than birch in the scrub-woodland and forest populations. Mean growth rates, mean age and median life expectancies increased significantly with sub-population of greater tree stature. At the population level, annual increment and longevity of birch stems was apparently interrelated as the stems in vigorously growing birch sub-populations had a longer life expectancy than those of slower growth. However, no difference was observed between sub-populations in age-related patterns of extension growth rate. The results were consistent with hypotheses (1), (3) and (4), but hypothesis (2) was rejected. Hence, mountain birch of more vigorous growth attains a greater stature than birch of lesser increment due to faster extension growth rate and a longer lifespan. In addition, the more contorted stem form of scrub populations contributes to their low stature.

Seroprevalence of Scrub Typhus Infection in Arunachal Pradesh, India.

PubMed

Jakharia, Aniruddha; Borkakoty, Biswajyoti; Biswas, Dipankar; Yadav, Kaushal; Mahanta, Jagadish

2016-10-01

Scrub typhus is a major reason for febrile illness, caused by a bacterium Orientia tsutsugamushi, a rickettsial pathogen. Few outbreaks of scrub typhus have been reported from Arunachal Pradesh in recent past. However, there is lack of seroprevalence data from the region. In this regard, this study was undertaken using archival serum sample available from seven districts of Arunachal Pradesh. This serological study was conducted in Regional Medical Research Center for NE Region, Dibrugarh. Reactivity to IgG class of antibodies against scrub typhus was done using Scrub typhus detect IgG ELISA kit as per manufacturer's protocol. Seroprevalence of scrub typhus in seven districts of Arunachal Pradesh was found to be 40% (120/300). The age-specific scrub typhus seroprevalence rose steadily from 5.6% in children <10 years of age to 61.8% in persons aged ≥40 years (p = 0.0001). Prevalence is lowest in Papumpare (25.9%) and highest in East Siang (72.5%) (p = 0.0001). The seroprevalence in males and females was very similar, however, the female prevalence increases from age group ≥30 years (p = 0.053). Moreover, among the farmers, the seroprevalence is higher (58.3%) (p = 0.0001). As clinical symptoms overlap with other viral/bacterial infections, scrub typhus infection should be considered in differential diagnosis of any acute febrile illness in this part of the country. In view of the high prevalence, empirical therapy of doxycycline/azithromycin may be done in cases of undiagnosed fever. Active surveillance has to be done to understand exact magnitude, epidemiological aspects, and distribution of vector and disease of this reemerging neglected tropical disease.

Predictors of acute myocarditis in complicated scrub typhus: an endemic province in the Republic of Korea.

PubMed

Chin, Jung Yeon; Kang, Ki-Woon; Moon, Kyung Min; Kim, Jongwoo; Choi, Yu Jeong

2018-03-01

Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus. We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn't have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis. Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001). Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed.

Predictors of acute myocarditis in complicated scrub typhus: an endemic province in the Republic of Korea

PubMed Central

Chin, Jung Yeon; Kang, Ki-Woon; Moon, Kyung Min; Kim, Jongwoo; Choi, Yu Jeong

2018-01-01

Background/Aims Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus. Methods We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn’t have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis. Results Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001). Conclusions Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed. PMID:28226202

Tsutsugamushi Disease (Scrub Typhus) Meningoencephalitis in North Eastern India: A Prospective Study.

PubMed

Sharma, S R; Masaraf, H; Lynrah, K G; Lyngdoh, M

2015-01-01

Scrub typhus is rampant in northern, eastern, and southern India. Central nervous system involvement in the form of meningitis or meningoencephalitis is common in scrub typhus. As specific laboratory methods remain inadequate or inaccessible in developing countries, prompt diagnosis is often difficult. The aim of this study was to characterize neurological complications in scrub typhus from northeastern region of India. We did a prospective study of scrub meningoencephalitis at North Eastern Indira Gandhi Regional Institute of Medical Sciences among patients admitted to hospital between October 2009 and November 2011. The diagnosis was made based on the clinical pictures, presence of an eschar, and a positive Weil-Felix test (WFT) with a titer of >1:160 and if required a positive scrub IgM enzyme-linked immunosorbent assay. Lumbar puncture was performed in patients with headache, nuchal rigidity, altered sensorium or cranial nerve deficits, and magnetic resonance imaging (MRI) brain performed if needed. Twenty-three patients of scrub typhus meningitis that were serologically confirmed were included in the study. There were 13 males and 10 females. Fever ≥1 week was the most common manifestation (39.1%). Interestingly, none had an eschar. Median cerebrospinal fluid (CSF) cell count, lymphocyte percentage, CSF protein, CSF glucose/blood glucose, CSF ADA were 17 cells/μL, 90%, 86 mg/dL, 0.6605 and 3.6 U/mL, respectively. All patients were treated with doxycycline. There was no mortality in our study. Absence of Eschar does not rule out scrub typhus. Clinical features and CSF findings can mimic tuberculous meningitis so misdiagnosis may lead to unwarranted prolonged empirical antituberculous therapy in cases of lymphocytic meningoencephalitis. Delay in treatment can be potentially fatal. WFT still serves as a useful and affordable diagnostic tool for this disease in resource-poor countries.

Cytokine Network in Scrub Typhus: High Levels of Interleukin-8 Are Associated with Disease Severity and Mortality

PubMed Central

Astrup, Elisabeth; Janardhanan, Jeshina; Otterdal, Kari; Ueland, Thor; Prakash, John A. J.; Lekva, Tove; Strand, Øystein A.; Abraham, O. C.; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M.

2014-01-01

Background Scrub typhus, caused by Orientia tsutsugamushi, is endemic in the Asia-Pacific region. Mortality is high if untreated, and even with treatment as high as 10–20%, further knowledge of the immune response during scrub typhus is needed. The current study was aimed at comparing plasma levels of a variety of inflammatory mediators in scrub typhus patients and controls in South India in order to map the broader cytokine profile and their relation to disease severity and clinical outcome. Methodology/Principal Findings We examined plasma levels of several cytokines in scrub typhus patients (n = 129) compared to healthy controls (n = 31) and infectious disease controls (n = 31), both in the acute phase and after recovery, by multiplex technology and enzyme immunoassays. Scrub typhus patients were characterized by marked changes in the cytokine network during the acute phase, differing not only from healthy controls but also from infectious disease controls. While most of the inflammatory markers were raised in scrub typhus, platelet-derived mediators such as RANTES were markedly decreased, probably reflecting enhanced platelet activation. Some of the inflammatory markers, including various chemokines (e.g., interleukin-8, monocyte chemoattractant peptide-1 and macrophage inflammatory protein-1β) and downstream markers of inflammation (e.g., C-reactive protein and pentraxin-3), were also associated with disease severity and mortality during follow-up, with a particular strong association with interleukin-8. Conclusions/Significance Our findings suggest that scrub typhus is characterized by a certain cytokine profile that includes dysregulated levels of a wide range of mediators, and that this enhanced inflammation could contribute to disease severity and clinical outcome. PMID:24516677

Air pollution from gas flaring: new emission factor estimates and detection in a West African aerosol remote-sensing climatology

NASA Astrophysics Data System (ADS)

MacKenzie, Rob; Fawole, Olusegun Gabriel; Levine, James; Cai, Xiaoming

2016-04-01

Gas flaring, the disposal of gas through stacks in an open-air flame, is a common feature in the processing of crude oil, especially in oil-rich regions of the world. Gas flaring is a prominent source of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAH), CO, CO2, nitrogen oxides (NOx), SO2 (in "sour" gas only), and soot (black carbon), as well as the release of locally significant amounts of heat. The rates of emission of these pollutants from gas flaring depend on a number of factors including, but not limited to, fuel composition and quantity, stack geometry, flame/combustion characteristics, and prevailing meteorological conditions. Here, we derive new estimated emission factors (EFs) for carbon-containing pollutants (excluding PAH). The air pollution dispersion model, ADMS5, is used to simulate the dispersion of the pollutants from flaring stacks in the Niger delta. A seasonal variation of the dispersion pattern of the pollutant within a year is studied in relation to the movements of the West Africa Monsoon (WAM) and other prevailing meteorological factors. Further, we have clustered AERONET aerosol signals using trajectory analysis to identify dominant aerosol sources at the Ilorin site in West Africa (4.34 oE, 8.32 oN). A 10-year trajectory-based analysis was undertaken (2005-2015, excluding 2010). Of particular interest are air masses that have passed through the gas flaring region in the Niger Delta area en-route the AERONET site. 7-day back trajectories were calculated using the UK Universities Global Atmospheric Modelling Programme (UGAMP) trajectory model which is driven by analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF). From the back-trajectory calculations, dominant sources are identified, using literature classifications: desert dust (DD); Biomass burning (BB); and Urban-Industrial (UI). We use a combination of synoptic trajectories and aerosol optical properties to distinguish a fourth source: that due to gas flaring. We discuss the relative impact of these different aerosol sources on the overall radiative forcing at Ilorin AERONET site.

Fuel cell cooler-humidifier plate

DOEpatents

Vitale, Nicholas G.; Jones, Daniel O.

2000-01-01

A cooler-humidifier plate for use in a proton exchange membrane (PEM) fuel cell stack assembly is provided. The cooler-humidifier plate combines functions of cooling and humidification within the fuel cell stack assembly, thereby providing a more compact structure, simpler manifolding, and reduced reject heat from the fuel cell. Coolant on the cooler side of the plate removes heat generated within the fuel cell assembly. Heat is also removed by the humidifier side of the plate for use in evaporating the humidification water. On the humidifier side of the plate, evaporating water humidifies reactant gas flowing over a moistened wick. After exiting the humidifier side of the plate, humidified reactant gas provides needed moisture to the proton exchange membranes used in the fuel cell stack assembly. The invention also provides a fuel cell plate that maximizes structural support within the fuel cell by ensuring that the ribs that form the boundaries of channels on one side of the plate have ends at locations that substantially correspond to the locations of ribs on the opposite side of the plate.

INL DPAH STAAR 2015 Annual Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterman, Dean Richard

2015-09-15

Research conducted at the INL has demonstrated the synergistic extraction of americium using solvents comprised of bis(o,o-(trifluoromethyl)phenyl) dithiophosphinic acid (DPAH “1”) and trioctylphosphine oxide (TOPO), butyl bis(2,4,4-trimethylpentyl) phosphinate (BuCy272), or dibutyl butylphosphonate (DBBP). One potential drawback of this separations scheme is that soft metals such as silver, cadmium, or palladium and fission products such as zirconium are well extracted by these solvents. Several potential scrubbing reagents were examined. Of the scrubbing reagents studied, cysteine and methione exhibited some ability to scrub soft metals from the loaded solvent. More conventional scrub reagents such as ammonium fluoride or oxalic acid were notmore » effective. Reagents like Bimet and CDTA were not soluble at the acidities used in these studies. Unfortunately, these results indicate that the identification of effective scrubbing reagents for use in a flowsheet based upon the INL DPAH is going to be very difficult.« less

Re-caching by Western scrub-jays (Aphelocoma californica) cannot be attributed to stress.

PubMed

Thom, James M; Clayton, Nicola S

2013-01-01

Western scrub-jays (Aphelocoma californica) live double lives, storing food for the future while raiding the stores of other birds. One tactic scrub-jays employ to protect stores is "re-caching"-relocating caches out of sight of would-be thieves. Recent computational modelling work suggests that re-caching might be mediated not by complex cognition, but by a combination of memory failure and stress. The "Stress Model" asserts that re-caching is a manifestation of a general drive to cache, rather than a desire to protect existing stores. Here, we present evidence strongly contradicting the central assumption of these models: that stress drives caching, irrespective of social context. In Experiment (i), we replicate the finding that scrub-jays preferentially relocate food they were watched hiding. In Experiment (ii) we find no evidence that stress increases caching. In light of our results, we argue that the Stress Model cannot account for scrub-jay re-caching.

Emission control system for nitrogen oxides using enhanced oxidation, scrubbing, and biofiltration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, A.; Cabezas, J.

2009-05-15

Nitric oxide (NO) constitutes about 90% of the nitrogen oxide (NOx) species in the flue gases emitted from combustion processes, but NO is difficult to remove in existing scrubbers due to its low solubility. NO may be oxidized with hydrogen peroxide (H{sub 2}O{sub 2}) into soluble species that can be partially removed in wet scrubbers simultaneously with sulfur dioxide (SO{sub 2}) and biofilters located downstream of the scrubber can increase the removal efficiency. This article presents the results of a bench-scale evaluation of such an integrated system combining enhanced oxidation, scrubbing, and biofiltration. Main components of the bench-scale system consistedmore » of a quartz tube in a furnace to simulate the NO oxidation stage and two vertical packed bed cylinders constituting the scrubber and the biofilter. Inlet synthetic gas had a concentration of 50 mu L/L of NO. Overall removal efficiency by the integrated system was in the range of 53% to 93% with an average of 79%, absorption accounted for 43% and biofiltration for 36% of the total removal. Key parameters in the operation of the system are the H{sub 2}O{sub 2}:NO mole ratio, the reaction temperature, the liquid to gas flow ratio, and the biofilter residence time. Experimental results suggest a path for optimization of the technology focusing simultaneously in minimizing H{sub 2}O{sub 2} use in the enhanced oxidation stage, reducing water consumption in the scrubber stage and balancing the residence times in the three stages of the integrated system.« less

Cross-flow electrochemical reactor cells, cross-flow reactors, and use of cross-flow reactors for oxidation reactions

DOEpatents

Balachandran, Uthamalingam; Poeppel, Roger B.; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Udovich, Carl A.

1994-01-01

This invention discloses cross-flow electrochemical reactor cells containing oxygen permeable materials which have both electron conductivity and oxygen ion conductivity, cross-flow reactors, and electrochemical processes using cross-flow reactor cells having oxygen permeable monolithic cores to control and facilitate transport of oxygen from an oxygen-containing gas stream to oxidation reactions of organic compounds in another gas stream. These cross-flow electrochemical reactors comprise a hollow ceramic blade positioned across a gas stream flow or a stack of crossed hollow ceramic blades containing a channel or channels for flow of gas streams. Each channel has at least one channel wall disposed between a channel and a portion of an outer surface of the ceramic blade, or a common wall with adjacent blades in a stack comprising a gas-impervious mixed metal oxide material of a perovskite structure having electron conductivity and oxygen ion conductivity. The invention includes reactors comprising first and second zones seprated by gas-impervious mixed metal oxide material material having electron conductivity and oxygen ion conductivity. Prefered gas-impervious materials comprise at least one mixed metal oxide having a perovskite structure or perovskite-like structure. The invention includes, also, oxidation processes controlled by using these electrochemical reactors, and these reactions do not require an external source of electrical potential or any external electric circuit for oxidation to proceed.

Method and apparatus for adding electrolyte to a fuel cell stack

DOE Office of Scientific and Technical Information (OSTI.GOV)

Congdon, J.V.; English, J.G.

1986-06-24

A process is described for adding electrolyte to a fuel cell stack, the stack comprising sheet-like elements defining a plurality of fuel cell units disposed one atop the other in abutting relationship, the units defining a substantially flat, vertically extending face, each unit including a cell comprising a pair of sheet-like spaced apart gas porous electrodes with a porous matrix layer sandwiched therebetween for retaining electrolyte during cell operation, each unit also including a sheet-like substantially non-porous separator, the separator being sandwiched between the cells of adjacent units. The improvement described here consists of: extending at least one of themore » sheet-like elements of each of a plurality of the fuel cell units outwardly from the stack face to define horizontal tabs disposed one above the other; depositing dilute electrolyte directly from electrolyte supply means upon substantially the full length, parallel to the stack face, of at least the uppermost tab, the tabs being constructed and arranged such that at least a portion of the deposited electrolyte cascades from tab to tab and down the face of the stack, the deposited electrolyte being absorbed by capillary action into the elements of the stack, the step of depositing continuing until all of the electrodes and matrix layers of the stack are fully saturated with the dilute electrolyte; and thereafter evaporating liquid from the saturated elements under controlled conditions of humidity and temperature until the stack has a desired electrolyte volume and electrolyte concentration therein.« less

Measurements of atmospheric nitrous acid and nitric acid

NASA Astrophysics Data System (ADS)

Huang, Gu; Zhou, Xianliang; Deng, Guohong; Qiao, Huancheng; Civerolo, Kevin

A highly sensitive technique for the measurement of atmospheric HONO and HNO 3 is reported. The technique is based on aqueous scrubbing using two coil samplers, followed by conversion of HNO 3 to nitrite, derivatization of nitrite to a highly light-absorbing azo dye with sulfanilamide (SA) and N-(1-naphthyl) ethylenediamine (NED), and high performance liquid chromatography (HPLC) analysis. HNO 3 concentration was obtained by the difference of the two channels. Two scrubbing solutions were used for sampling the two species: a 1-mM phosphate buffer solution (pH 7) for the measurement of HONO and a 180 mM NH 4Cl/NH 3 buffer solution (pH 8.5) for the measurement of HONO+HNO 3. The scrubbing solution flow rate was 0.24 ml min -1 and the gas sampling flow rate was 2 l min -1. HNO 3 in the NH 4Cl/NH 3 buffer solution was quantitatively reduced to nitrite along an on-line 0.8-cm Cd reductor column. Nitrite in both channels was derivatized with 2 mM SA and 0.2 mM NED in 25 mM HCl. Quantitative derivatization was achieved within 5 min at 55°C. The azo dye derivative was then separated from the SA/NED reagent by reversed-phase HPLC and detected with a UV-vis detector at 540 nm. With an on-line SEP-PAK C-18 cartridge for the reagent purification, the method detection limit is estimated to be better than 1 pptv for HONO and about 20 pptv for HNO 3. The sample integration time was about 2 min and the sampling frequency is every 10 min. Data collected in downtown Albany and Whiteface Mountain, NY, are shown as examples of applications of this technique in both urban and remote clean environments.

Deep magmatic degassing versus scrubbing: Elevated CO2 emissions and C/S in the lead-up to the 2009 eruption of Redoubt Volcano, Alaska

USGS Publications Warehouse

Werner, Cynthia A.; Evans, William C.; Kelly, Peter; McGimsey, Robert G.; Pfeffer, Melissa; Doukas, Michael P.; Neal, Christina

2012-01-01

We report CO2, SO2, and H2S emission rates and C/S ratios during the five months leading up to the 2009 eruption of Redoubt Volcano, Alaska. CO2emission rates up to 9018 t/d and C/S ratios ≥30 measured in the months prior to the eruption were critical for fully informed forecasting efforts. Observations of ice-melt rates, meltwater discharge, and water chemistry suggest that surface waters represented drainage from surficial, perched reservoirs of condensed magmatic steam and glacial meltwater. These fluids scrubbed only a few hundred tonnes/day of SO2, not the >2100 t/d SO2expected from degassing of magma in the mid- to upper crust (3–6.5 km), where petrologic analysis shows the final magmatic equilibration occurred. All data are consistent with upflow of a CO2-rich magmatic gas for at least 5 months prior to eruption, and minimal scrubbing of SO2by near-surface groundwater. The high C/S ratios observed could reflect bulk degassing of mid-crustal magma followed by nearly complete loss of SO2in a deep magmatic-hydrothermal system. Alternatively, high C/S ratios could be attributed to decompressional degassing of low silica andesitic magma that intruded into the mid-crust in the 5 months prior to eruption, thereby mobilizing the pre-existing high silica andesite magma or mush in this region. The latter scenario is supported by several lines of evidence, including deep long-period earthquakes (−28 to −32 km) prior to and during the eruption, and far-field deformation following the onset of eruptive activity.

Factors Affecting Florida Scrub-Jay Nest Survival on Ocala National Forest, Florida

Treesearch

Kathleen Franzreb; Stan Zarnoch

2011-01-01

One of the main populations of the Florida scrub-jay (Aphelocoma coerulescens), a federally threatened species, occurs on Ocala National Forest, Florida. We determined the nest survival rate (DSR) of 474 nests of Florida scrub-jays in stands subject to sand pine reforestation management after timber harvesting or wildfire on Ocala National Forest. We used the...

A multiscale landscape approach to predicting bird and moth rarity hotspots in a threatened pitch pine-scrub oak community

Treesearch

Joanna Grand; John Buonaccorsi; Samuel A. Cushman; Curtice R. Griffin; Maile C. Neel

2004-01-01

In the northeastern United States, pitch pine (Pinus rigida Mill.)-scrub oak (Quercus ilicifolia Wang.) communities are increasingly threatened by development and fire suppression, and prioritization of these habitats for conservation is of critical importance. As a basis for local conservation planning in a pitch pine-scrub oak community in southeastern Massachusetts...

High seroprevalence of antibodies against spotted fever and scrub typhus bacteria in patients with febrile Illness, Kenya.

PubMed

Thiga, Jacqueline W; Mutai, Beth K; Eyako, Wurapa K; Ng'ang'a, Zipporah; Jiang, Ju; Richards, Allen L; Waitumbi, John N

2015-04-01

Serum samples from patients in Kenya with febrile illnesses were screened for antibodies against bacteria that cause spotted fever, typhus, and scrub typhus. Seroprevalence was 10% for spotted fever group, <1% for typhus group, and 5% for scrub typhus group. Results should help clinicians expand their list of differential diagnoses for undifferentiated fevers.

Moisturizing alcohol hand gels for surgical hand preparation.

PubMed

Jones, R D; Jampani, H; Mulberry, G; Rizer, R L

2000-03-01

With the use of novel formulary technology, unique moisturizing hand gels have been developed that offer significant advantages in perioperative and other health care settings. These advantages include the time-saving capabilities of a waterless formulation, the persistence and effectiveness of a surgical scrub, and the moisturization and protective properties of a lotion. Extensive laboratory and clinical studies, involving in vivo antimicrobial activity against resident and transient flora, skin moisturization on normal and dry skin, and compatibility with latex gloves, have supported these advantages. Nondrying alcohol hand gels can be used for antiseptic hand washing, hand scrubs between procedures (i.e., reentry scrubs), brushless surgical scrubs, moisturizers, and glove-donning aids.

A New Population Estimate for the Florida Scrub Jay on Merritt Island National Wildlife Refuge

NASA Technical Reports Server (NTRS)

Breininger, David R.

1989-01-01

The variable circular plot method was used to sample avifauna within different vegetation types determined from aerial imagery. The Florida Scrub Jay (Aphelocoma coerulescens coerulescens) population was estimated to range between 1,415 and 3,603 birds. Approximately half of the scrub and slash pine habitat appeared to be unused by Florida Scrub Jay, probably because the slash pine cover was too dense or the oak cover was too sparse. Results from the study suggest that the entire state population may be much lower than believed because the size of two of the three largest populations may have been overestimated.

Active material for fiber core made by powder-in-tube method: subsequent homogenization by means of stack-and-draw technique

NASA Astrophysics Data System (ADS)

Velmiskin, Vladimir V.; Egorova, Olga N.; Mishkin, Vladimir; Nishchev, Konstantin; Semjonov, Sergey L.

2012-04-01

A procedure for the preparation of optically homogeneous glass for fiber preforms through sintering of coarse oxide particles and further processing of the resultant glass, including several drawing and stacking steps, is described. Reducing the pressure to 10-2 Torr during sintering considerably reduced the amount of gas bubbles in Yb/Al-doped silica glass and decreased the background loss to 100 dB/km after the third drawing-stacking-consolidation cycle. For comparison, a fiber singly doped with alumina was fabricated by the same procedure as above. The level of wavelength- independent losses in that fiber was 65 dB/km.

Effects of fire on composition, biomass, and nutrients in oak scrub vegetation on John F. Kennedy Space Center, Florida

NASA Technical Reports Server (NTRS)

Schmalzer, Paul A.; Hinkle, C. Ross

1987-01-01

Four stands of oak scrub two, four, eight, and 25 years since fire were sampled with permanent 15 m line transects. Percent cover by species was determined. Plant samples were analyzed for a variety of substances. Transects were resurveyed in 1985 for vegetation parameters. Nutrient pools in biomass were calculated from biomass data and tissue nutrient concentrations. Soil nutrient pools were calculated from nutrient concentrations and bulk density. Species distribution and soil chemical properties were found to be closely related to water table depth. The following fire-related conclusions are reached: (1) major structural changes occur in scrub after fire in that shrub height is reduced and requires four to six years to exceed 1 m; (2) reduction in shrub height affects the suitability of scrub for the Florida scrub jay (3) live biomass increases with time since fire; (4) nutrient concentrations in live biomass do not change with time since fire; (5) species composition and richness are little changed after fire; and (6) imposition of a continued regime of burning on a three-year cycle may have adverse impacts not indicated by the recovery of scrub from a single fire.

An Assessment of Fission Product Scrubbing in Sodium Pools Following a Core Damage Event in a Sodium Cooled Fast Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bucknor, M.; Farmer, M.; Grabaskas, D.

The U.S. Nuclear Regulatory Commission has stated that mechanistic source term (MST) calculations are expected to be required as part of the advanced reactor licensing process. A recent study by Argonne National Laboratory has concluded that fission product scrubbing in sodium pools is an important aspect of an MST calculation for a sodium-cooled fast reactor (SFR). To model the phenomena associated with sodium pool scrubbing, a computational tool, developed as part of the Integral Fast Reactor (IFR) program, was utilized in an MST trial calculation. This tool was developed by applying classical theories of aerosol scrubbing to the decontamination ofmore » gases produced as a result of postulated fuel pin failures during an SFR accident scenario. The model currently considers aerosol capture by Brownian diffusion, inertial deposition, and gravitational sedimentation. The effects of sodium vapour condensation on aerosol scrubbing are also treated. This paper provides details of the individual scrubbing mechanisms utilized in the IFR code as well as results from a trial mechanistic source term assessment led by Argonne National Laboratory in 2016.« less

Scrub typhus: radiological and clinical findings in abdominopelvic involvement.

PubMed

Kim, Kun Yung; Song, Ji Soo; Park, Eun Hae; Jin, Gong Yong

2017-03-01

To describe the clinical and radiological findings of abdominopelvic involvement in scrub typhus. Abdominopelvic computed tomography (CT) of 78 patients with scrub typhus were evaluated by two readers. The presence of gallbladder wall thickening, arterial inhomogeneous enhancement of the liver, periportal edema, splenic infarction, hepatomegaly, splenomegaly, ascites, pleural effusion, and sites of lymphadenopathy were evaluated. Patients were divided into four clinical subgroups according to laboratory findings. Association between imaging findings and subgroups was analyzed by Chi squared test or Fisher's exact test. The most common CT finding was hepatomegaly (74.4%), followed by splenomegaly (66.7%). The majority of patients had at least three areas of abdominopelvic lymphadenopathy (71.8%). Pelvic lymphadenopathy was most commonly seen when eschar was found in the ipsilateral lower extremity (left, n = 5/7; right, n = 8/13). Significant association between hepatic dysfunction and perigastric lymphadenopathy was documented (p = 0.03). Scrub typhus has a spectrum of variable clinical and radiological findings mimicking those of acute hepatitis. Diffuse abdominopelvic lymphadenopathy involving the retroperitoneum and pelvic area may aid in early diagnosis of scrub typhus. Perigastric lymphadenopathy could be a sign of severe scrub typhus combined with hepatic dysfunction.

Molecular characterization of Orientia tsutsugamushi serotypes causing scrub typhus outbreak in southern region of Andhra Pradesh, India.

PubMed

Usha, K; Kumar, E; Kalawat, Usha; Kumar, B Siddhartha; Chaudhury, A; Gopal, D V R Sai

2016-10-01

Scrub typhus is a vector-borne zoonotic infection caused by Orientiatsutsugamushi. Local epidemiology of the circulating serotypes of scrub typhus is not available from most parts of India. We conducted this study for the diagnosis of scrub typhus using IgM ELISA and to detect O. tsutsugamushi serotypes circulating in southern Andhra Pradesh, India. Samples were collected from patients clinically suspected to have scrub typhus and were subjected to IgM ELISA to measure IgM antibodies against O. tsutsugamushi. Nested polymerase chain reaction (PCR) was performed targeting strain-specific regions in ELISA-positive samples. Of a total of 663 samples, 258 (38.91%) were found to be positive by IgM ELISA. Serotypes could be detected in 230 (34.69%) samples only. Only two serotypes, Karp and Kawasaki, were found in the serum samples, with the former being predominant. The dual infection of Karp and Kawasaki serotypes was found in seven patients. Other serotypes such as Gilliam, Kuroki and Kato were not detected in the samples. The nested PCR products proved useful in presumptively identifying the endemic O. tsutsugamushi serotypes. The present study could be significant in understanding scrub typhus epidemiology in this region.

Scrub typhus associated hepatic dysfunction and abdominal CT findings

PubMed Central

Park, Man Je; Lee, Hyoun Soo; Shim, Sang Goon; Kim, So Hee

2015-01-01

Objective: This retrospective study investigated abnormal hepatic dysfunction and abdominal computed tomography (CT) findings in scrub typhus. Methods: Three hundred forty nine adult patients were diagnosed with scrub typhus. Ninety four underwent abdominal CT. The CT images were reviewed by the attending radiologist. Patient data of history, symptoms, signs, and results of laboratory tests were collected from the electronic medical records. Results: In 349 patients with scrub typhus, elevation of aspartate aminotransferase (78.5%) and alanine aminotransferase (63.0%) were dominant compared to alkaline phosphatase (27.2%) and total bilirubin (16.1%). Abdominal CT findings of 94 patients were, in descending order of frequency, enlarged lymph node (53.2%), inhomogeneous enhancement of liver (47.9%), splenomegaly (46.8%), ascites (28.7%), low attenuation of periportal areas (27.7%), gallbladder wall thickening (17.0%), and splenic infarct (6.4%). Also, the level of aspartate aminotransferase tended to be elevated according to the number of CT findings (P= 0.028) Conclusions: We found that abdominal CT manifestations of scrub typhus with elevated aminotransferases were varied and not specific. However, knowledge of these findings may evoke the recognition of scrub typhus by clinicians in endemic areas. PMID:26101478

The Correlation of Endoscopic Findings and Clinical Features in Korean Patients with Scrub Typhus: A Cohort Study

PubMed Central

Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo

2016-01-01

Scrub typhus is an infectious disease caused by Orientia tsutsugamushi-induced systemic vasculitis, but the involvement of the gastrointestinal tract and the endoscopic findings associated with scrub typhus are not well understood. We performed a prospective study and recommend performing esophagogastroduodenoscopy (EGD) for all possible scrub typhus patients, regardless of gastrointestinal symptoms. Gastrointestinal symptoms, endoscopic findings and clinical severity based on organ involvement and ICU admission were analyzed. Gastrointestinal symptoms occurred in up to 76.4% of scrub typhus patients. The major endoscopic findings were ulcers (43/127, 33.9%). Interestingly, 7.1% (9/127) of the patients presented with esophageal candidiasis. There was no correlation between the presence or absence of gastrointestinal symptoms and the endoscopic grade (P = 0.995). However, there was a positive correlation between the clinical severity and the endoscopic findings (P = 0.001). Sixty-three percent of the patients presented with erosion or ulcers on prospectively performed endoscopic evaluations, irrespective of gastrointestinal symptoms. Gastrointestinal symptoms did not reflect the need for endoscopy. Scrub typhus patients could have significant endoscopic abnormalities even in the absence of gastrointestinal symptoms. PMID:27195943

Assessing the Greenhouse Gas Emissions from Natural Gas Fired Power Plants

NASA Astrophysics Data System (ADS)

Hajny, K. D.; Shepson, P. B.; Rudek, J.; Stirm, B. H.; Kaeser, R.; Stuff, A. A.

2017-12-01

Natural gas is often discussed as a "bridge fuel" to transition to renewable energy as it only produces 51% the amount of CO2 per unit energy as coal. This, coupled with rapid increases in production fueled by technological advances, has led to a near tripling of natural gas used for electricity generation since 2005. One concern with this idea of a "bridge fuel" is that methane, the primary component of natural gas, is itself a potent greenhouse gas with 28 and 84 times the global warming potential of CO2 based on mass over a 100 and 20 year period, respectively. Studies have estimated that leaks from the point of extraction to end use of 3.2% would offset the climate benefits of natural gas. Previous work from our group saw that 3 combined cycle power plants emitted unburned CH4 from the stacks and leaked additional CH4 from equipment on site, but total loss rates were still less than 2.2%. Using Purdue's Airborne Laboratory for Atmospheric Research (ALAR) we completed additional aircraft based mass balance experiments combined with passes directly over power plant stacks to expand on the previous study. In this work, we have measured at 12 additional natural gas fired power plants including a mix of operation types (baseload, peaking, intermediate) and firing methods (combined cycle, simple thermal, combustion turbine). We have also returned to the 3 plants previously sampled to reinvestigate emissions for each of those, to assess reproducibility of the results. Here we report the comparison of reported continuous emissions monitoring systems (CEMS) data for CO2 to our emission rates calculated from mass balance experiments, as well as a comparison of calculated CH4 emission rates to estimated emission rates based on the EPA emission factor of 1 g CH4/mmbtu natural gas and CEMS reported heat input. We will also discuss emissions from a coal-fired plant which has been sampled by the group in the past and has since converted to natural gas. Lastly, we discuss the ratio of CH4 to CO2 in stack based emissions as it relates to our calculated emission rates and as compared to the same ratio for the emission factors.

Evaluating geophysical lithology determination methods in the central offshore Nile Delta, Egypt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nada, H.; Shrallow, J.

1994-12-31

Two post stack and one prestack geophysical techniques were used to extract lithology and fluid information from seismic data. The purpose of this work was to evaluate the effectiveness of such methods in helping to find more hydrocarbons and reduce exploration risk in Egypt`s Nile Delta. Amplitude Variations with Offset (AVO) was used as a direct hydrocarbon indicator. CDP gathers were sorted into common angle gathers. The angle traces from 0--10 degrees were stacked to form a near angle stack and those from 30--40 degrees were stacked to form a far angle stack. Comparison of the far and near anglemore » stacks indicate areas which have seismic responses that match gas bearing sand models in the Pliocene and Messinian. Seismic Sequence Attribute mapping was used to measure the reflectivity of a seismic sequence. The specific sequence attribute measured in this study was the Maximum Absolute Amplitude of the seismic reflections within a sequence. Post stack seismic inversion was used to convert zero phase final migrated data to pseudo acoustic impedance data to interpret lithology from seismic data. All three methods are useful in the Nile Delta for identifying sand prone areas, but only AVO can be used to detect fluid content.« less

Assessment of the LV-C2 Stack Sampling Probe Location for Compliance with ANSI/HPS N13.1-1999

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glissmeyer, John A.; Antonio, Ernest J.; Flaherty, Julia E.

2015-09-01

This document reports on a series of tests conducted to assess the proposed air sampling location for the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste (LAW) C2V (LV-C2) exhaust stack with respect to the applicable criteria regarding the placement of an air sampling probe. Federal regulations require that a sampling probe be located in the exhaust stack according to the criteria established by the American National Standards Institute/Health Physics Society (ANSI/HPS) N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stack and Ducts of Nuclear Facilities. These criteria address the capability of the sampling probemore » to extract a sample that represents the effluent stream. The tests were conducted on the LV-C2 scale model system. Based on the scale model tests, the location proposed for the air sampling probe in the scale model stack meets the requirements of the ANSI/HPS N13.1-1999 standard for velocity uniformity, flow angle, gas tracer and particle tracer uniformity. Additional velocity uniformity and flow angle tests on the actual stack will be necessary during cold startup to confirm the validity of the scale model results in representing the actual stack.« less

Cold Flow Testing of a Modified Subscale Model Exhaust System for a Space Based Laser

DTIC Science & Technology

2004-06-01

Abstract The aim of this research was a continued study of gas-dynamic phenomena that occurred in a set of stacked nozzles as reported by Captains...join the vacuum and test sections. The goals of this research were two fold; first, modify the original scale-model of the stacked cylindrical...Defense Advanced Research Projects Agency (DARPA), in conjunction with the Airborne Laser Laboratory, have studied the use of an Airborne Laser (ABL

A novel fast-neutron detector concept for energy-selective imaging and imaging spectroscopy.

PubMed

Cortesi, M; Dangendorf, V; Zboray, R; Prasser, H-M

2014-07-01

We present and discuss the operational principle of a new fast-neutron detector concept suitable for either energy-selective imaging or for imaging spectroscopy. The detector is comprised of a series of energy-selective stacks of converter foils immersed in a noble-gas based mixture, coupled to a position-sensitive charge readout. Each foil in the various stacks is made of two layers of different thicknesses, fastened together: a hydrogen-rich (plastic) layer for neutron-to-proton conversion, and a hydrogen-free coating to selectively stop/absorb the recoil protons below a certain energy cut-off. The neutron-induced recoil protons, that escape the converter foils, release ionization electrons in the gas gaps between consecutive foils. The electrons are then drifted towards and localized by a position-sensitive charge amplification and readout stage. Comparison of the images detected by stacks with different energy cut-offs allows energy-selective imaging. Neutron energy spectrometry is realized by analyzing the responses of a sufficient large number of stacks of different energy response and unfolding techniques. In this paper, we present the results of computer simulation studies and discuss the expected performance of the new detector concept. Potential applications in various fields are also briefly discussed, in particularly, the application of energy-selective fast-neutron imaging for nuclear safeguards application, with the aim of determining the plutonium content in Mixed Oxide (MOX) fuels.

Scrub typhus islands in the Taiwan area and the association between scrub typhus disease and forest land use and farmer population density: geographically weighted regression.

PubMed

Tsai, Pui-Jen; Yeh, Hsi-Chyi

2013-04-29

The Taiwan area comprises the main island of Taiwan and several small islands located off the coast of the Southern China. The eastern two-thirds of Taiwan are characterized by rugged mountains covered with tropical and subtropical vegetation. The western region of Taiwan is characterized by flat or gently rolling plains. Geographically, the Taiwan area is diverse in ecology and environment, although scrub typhus threatens local human populations. In this study, we investigate the effects of seasonal and meteorological factors on the incidence of scrub typhus infection among 10 local climate regions. The correlation between the spatial distribution of scrub typhus and cultivated forests in Taiwan, as well as the relationship between scrub typhus incidence and the population density of farm workers is examined. We applied Pearson's product moment correlation to calculate the correlation between the incidence of scrub typhus and meteorological factors among 10 local climate regions. We used the geographically weighted regression (GWR) method, a type of spatial regression that generates parameters disaggregated by the spatial units of analysis, to detail and map each regression point for the response variables of the standardized incidence ratio (SIR)-district scrub typhus. We also applied the GWR to examine the explanatory variables of types of forest-land use and farm worker density in Taiwan in 2005. In the Taiwan Area, scrub typhus endemic areas are located in the southeastern regions and mountainous townships of Taiwan, as well as the Pescadore, Kinmen, and Matou Islands. Among these islands and low-incidence areas in the central western and southwestern regions of Taiwan, we observed a significant correlation between scrub typhus incidence and surface temperature. No similar significant correlation was found in the endemic areas (e.g., the southeastern region and the mountainous area of Taiwan). Precipitation correlates positively with scrub typhus incidence in 3 local climate regions (i.e., Taiwan's central western and southwestern regions, and the Kinmen Islands). Relative humidity correlates positively with incidence in Southwestern Taiwan and the Kinmen Islands. The number of wet days correlates positively with incidence in Southwestern Taiwan. The duration of sunshine correlates positively with incidence in Central Western Taiwan, as well as the Kinmen and Matou Islands. In addition, the 10 local climatic regions can be classified into the following 3 groups, based on the warm-cold seasonal fluctuations in scrub typhus incidence: (a) Type 1, evident in 5 local climate regions (Taiwan's northern, northwestern, northeastern, and southeastern regions, as well as the mountainous area); (b) Type 2 (Taiwan's central western and southwestern regions, and the Pescadore Islands); and (c) Type 3 (the Kinmen and Matou Islands). In the GWR models, the response variable of the SIR-district scrub typhus has a statistically significantly positive association with 2 explanatory variables (farm worker population density and timber management). In addition, other explanatory variables (recreational forests, natural reserves, and "other purpose" areas) show positive or negative signs for parameter estimates in various locations in Taiwan. Negative signs of parameter estimates occurred only for the explanatory variables of national protectorates, plantations, and clear-cut areas. The results of this study show that scrub typhus in Taiwan can be classified into 3 types. Type 1 exhibits no climatic effect, whereas the incidence of Type 2 correlates positively with higher temperatures during the warm season, and the incidence of Type 3 correlates positively with higher surface temperatures and longer hours of sunshine. The results also show that in the mountainous township areas of Taiwan's central and southern regions, as well as in Southeastern Taiwan, higher SIR values for scrub typhus are associated with the following variables: farm worker population density, timber management, and area type (i.e., recreational forest, natural reserve, or other purpose).