Note: This page contains sample records for the topic carbon carbon monoxide from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
1

Carbon monoxide  

PubMed Central

Carbon monoxide (CO), a by-product released during the degradation of heme by heme oxygenases (HOS EC 1.14.99.3) in animals, plays a major role as neurotransmitter, regulator of sinusoidal tone, inhibitor of platelet aggregation and suppressor of acute hypertensive response, and most of above effects are similar to or mediated by nitric oxide (NO), another signal molecule in both the animal and plant kingdoms. Previous result demonstrated that NO could act as a promoter of plant cell elongation, acting similarly to IAA, inducing morphogenetic responses leading to expansion in plant tissues. Recent observations revealed that CO is an inducer of cell expansion in wheat root segments, acting similarly to IAA and NO. Evidence also indicated that IAA could result in either the potent induction of HO-1 transcript or endogenous CO releasing in wheat root segments. Additionally, our results suggested that above CO signaling might be related to NO/cGMP, Ca2+ and even ROS-dependent pathways. In this addendum, combined with other previous results, we further proposed a possible hypothesis for CO signaling role in regulation of plant root development induced by auxin.

Xuan, Wei; Xu, Sheng; Yuan, Xingxing

2008-01-01

2

Carbon Monoxide Information Center  

MedlinePLUS Videos and Cool Tools

... Space Saving Sleep Solutions More CO Blogs Research & Statistics Non-Fire Carbon Monoxide Deaths Associated with the ... Driven Tools, 1999-2011 View All CO Research & Statistics Reports Inside CPSC: Recalls Safety Education Regulations, Laws & ...

3

Carbon monoxide intoxication  

SciTech Connect

Carbon monoxide poisoning usually results from inhalation of exhaust fumes from motor vehicles, smoke from fires or fumes from faulty heating systems. Carbon monoxide has a high affinity for hemoglobin, with which it forms carboxyhemoglobin. The resulting decrease in both oxygen-carrying capacity and oxygen release can lead to end-organ hypoxia. The clinical presentation is nonspecific. Headache, dizziness, fatigue and nausea are common in mild to moderate carbon monoxide poisoning. In more severe cases, tachycardia, tachypnea and central nervous system depression occur. When carbon monoxide intoxication is suspected, empiric treatment with 100 percent oxygen should be initiated immediately. The diagnosis is confirmed by documenting an elevated carboxyhemoglobin level. Hyperbaric oxygen therapy is recommended in patients with neurologic dysfunction, cardiac dysfunction or a history of unconsciousness. 26 refs.

Kales, S.N. (Cambridge Hospital, MA (United States))

1993-11-01

4

Carbon monoxide poisoning  

MedlinePLUS

... Portable propane heaters Stoves (indoor and camp stoves) Water heater that use natural gas Note: This list may ... gas-burning appliances (such as a furnace or water heater). Many carbon monoxide poisonings occur in the winter ...

5

Estimating carbon monoxide exposure  

NASA Technical Reports Server (NTRS)

Method predicts effects of carbon monoxide on astronauts confined in spacecraft cabin atmospheres. Information on need for low toxicity level also applies to confined spaces. Benefits are applicable to industry and public health.

Edgerley, R. H.

1971-01-01

6

Carbon Monoxide (CO)  

MedlinePLUS

... CO are expected for short periods of time. ALERT: Put generators outside. Never use a generator inside ... Security, U.S. Fire Administration's Portable Generator Hazards page ALERT!! Preventing Carbon Monoxide Poisoning from Small Gasoline-Powered ...

7

Solid State Carbon Monoxide Sensor  

NASA Technical Reports Server (NTRS)

A means for detecting carbon monoxide which utilizes an un-heated catalytic material to oxidize carbon monoxide at ambient temperatures. Because this reaction is exothermic, a thermistor in contact with the catalytic material is used as a sensing element to detect the heat evolved as carbon monoxide is oxidized to carbon dioxide at the catalyst surface, without any heaters or external heating elements for the ambient air or catalytic element material. Upon comparison to a reference thermistor, relative increases in the temperature of the sensing thermistor correspond positively with an increased concentration of carbon monoxide in the ambient medium and are thus used as an indicator of the presence of carbon monoxide.

Upchurch, Billy T. (Inventor); Wood, George M. (Inventor); Schryer, David R. (Inventor); Leighty, Bradley D. (Inventor); Oglesby, Donald M. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); DAmbrosia, Christine M. (Inventor)

1999-01-01

8

Mass carbon monoxide poisoning  

PubMed Central

The largest occurrence of carbon monoxide poisoning in Britain demonstrates the potential for mass accidental poisoning. It emphasises the need for strict public health controls and the importance of good liaison between emergency services to ensure that such events are quickly recognised and that the necessary resources are organised.

McGuffie, C; Wyatt, J; Kerr, G; Hislop, W

2000-01-01

9

Transmissivity of carbon monoxide  

NASA Technical Reports Server (NTRS)

The line strengths and self- and nitrogen-broadened half widths for selected lines of the 4.6 micron fundamental band of carbon monoxide were determined. The band strength determined at stp. is higher than previously reported measurements. The half widths agree well with other measurements and calculations.

Drayson, S. R.; Tallamraju, R.; Chaney, L. W.

1973-01-01

10

Carbon Monoxide Sensor  

NASA Technical Reports Server (NTRS)

The fuel cell is a system which employs an electrochemical process to convert gases- J such as hydrogen and oxygen directly into electricity. Under NASA sponsorship, GE's Aircraft Equipment Division developed fuel cells to supply electrical power for the Gemini and Biosatellite spacecraft of the sixties and is currently working on advanced fuel cell development. This long-term effort has resulted in a series of spinoff applications using the same general technology for a variety of purposes, among them the recently marketed Dosimeter. The Dosimeter is designed to help users meet safety requirements for industrial atmospheres, as specified by the Occupational Safety and Health Administration and other regulatory agencies. The compact, pocket-sized sensor measures personnel exposure to carbon monoxide and provides both a visual and an audible alarm if the concentration of the gas exceeds present levels. The Dosimeter offers substantial improvement in measuring accuracy over earlier warning indicators.

1978-01-01

11

Carbon monoxide: Anticoagulant or procoagulant?  

PubMed

Within the past decade there have been several investigations attempting to define the impact of exogenous and endogenous carbon monoxide exposure on hemostasis. Critically, two bodies of literature have emerged, with carbon monoxide mediated platelet inhibition cited as a cause of in vitro human and in vitro/in vivo rodent anticoagulation. In contrast, interaction with heme groups associated with fibrinogen, ??-antiplasmin and plasmin by carbon monoxide has resulted in enhanced coagulation and decreased fibrinolysis in vitro in human and other species, and in vivo in rabbits. Of interest, the ultrastructure of platelet rich plasma thrombi demonstrates an abnormal increase in fine fiber formation and matting that are obtained from humans exposed to carbon monoxide. Further, thrombi obtained from humans and rabbits have very similar ultrastructures, whereas mice and rats have more fine fibers and matting present. In sum, there may be species specific differences with regard to hemostatic response to carbon monoxide. Carbon monoxide may be a Janus-faced molecule, with potential to attenuate or exacerbate thrombophilic disease. PMID:24360115

Nielsen, Vance G; Pretorius, Etheresia

2014-03-01

12

Microbial growth on carbon monoxide  

Microsoft Academic Search

The utilization of carbon monoxide as energy and\\/or carbon source by different physiological groups of bacteria is described and compared. Utilitarian CO oxidation which is coupled to the generation of energy for growth is achieved by aerobic and anaerobic eu- and archaebacteria. They belong to the physiological groups of aerobic carboxidotrophic, facultatively anaerobic phototrophic, and anaerobic acetogenic, methanogenic or sulfate-reducing

Gerhard Mörsdorf; Kurt Frunzke; Dilip Gadkari; Ortwin Meyer

1992-01-01

13

Carbon monoxide in the home environment  

SciTech Connect

This study was designed to evaluate carbon monoxide exposure in homes equipped with vented and unvented heating systems by monitoring air and resident expired breath in order to calculate of blood carbon monoxide levels. Carbon monoxide in air and expired breath data were evaluated utilizing existing exposure assessment models for blood carbon monoxide determinations. Results of the study indicated that carbon monoxide exposure and subsequent uptake by home residents are at levels exceeding that threshold of subjective and objective system response and may attribute to ill health. The mean carbon monoxide level in home air ranged from 3.0 to 105 ppm with calculated blood carbon monoxide values that range from 0.632 to 2.681%. 85% of the vented homes studied had an average daily carbon monoxide level at or below 7.0 ppm in comparison to 83% of the unvented homes with an average daily carbon monoxide level at or below 27.0 ppm.

Love, A.L.

1986-01-01

14

Carbon Monoxide and Population Density  

NSDL National Science Digital Library

This lesson is designed to help students gain knowledge in using the MY NASA DATA Live Access Server (LAS) to specify and download a microset of data, then to use the data to investigate the carbon monoxide level at a fixed latitude. Using the LAS, students will download data, and then will use Excel to create maps of the carbon monoxide level for a particular latitude. They will then look for trends and explore the population density for selected points along the latitude (urban or rural). The lesson provides detailed procedure, related links and sample graphs, follow-up questions and extensions, and Teacher Notes.

2010-03-14

15

(Carbon monoxide metabolism by photosynthetic bacteria)  

SciTech Connect

Research continued on the metabolism of carbon monoxide by Rhodospirillum rubrum. This report discusses progress on the activity, induction, inhibition, and spectroscopic analysis of the enzyme Carbon Monoxide Dehydrogenase. (CBS)

Not Available

1989-01-01

16

Carbon Monoxide from Biomass Burning  

NASA Technical Reports Server (NTRS)

This pair of images shows levels of carbon monoxide at the atmospheric pressure level of 700 millibars (roughly 12,000 feet in altitude) over the continent of South America, as observed by the Measurements Of Pollution In The Troposphere (MOPITT) sensor flying aboard NASA's Terra spacecraft. Data for producing the image on the left were acquired on March 3, 2000, and for the image on the right on September 7, 2000. Blue pixels show low values, yellows show intermediate values, and the red to pink and then white pixels are progressively higher values. In the lefthand image (March 3), notice the fairly low levels of carbon monoxide over the entire continent. The slightly higher equatorial values are the result of burning emissions in sub-Saharan Africa that are convected at the Intertropical Convergence Zone (ITCZ) and spread by the trade winds. Also, notice the effect of the elevated surface topography across the Andes Mountains running north to south along the western coastline. (In this region, white pixels show no data.) In the righthand image (September 7), a large carbon monoxide plume is seen over Brazil, produced primarily by biomass burning across Amazonia and lofted into the atmosphere by strong cloud convection. The generally higher carbon monoxide levels as compared to March are both the result of South American fire emissions and the transport of carbon monoxide across the Atlantic Ocean from widespread biomass burning over Southern Africa. These images were produced using MOPITT data, which are currently being validated. These data were assimilated into an atmospheric chemical transport model using wind vectors provided by the National Center for Environmental Prediction (NCEP). Although there is good confidence in the relative seasonal values and geographic variation measured by MOPITT, that team anticipates their level of confidence will improve further with ongoing intensive validation campaigns and comparisons with in situ and ground-based spectroscopic measurements. Images courtesy David Edwards and John Gille, MOPITT Science Team, NCAR

2002-01-01

17

Anthropogenic emissions of carbon monoxide.  

PubMed

Carbon monoxide (CO) is a colorless, nonirritating, odorless and tasteless gas. Carbon monoxide combines with hemoglobin far more readily than does oxygen, leading to tissue hypoxia. Thousands of people die annually from CO poisoning, and those recovering from acute exposure commonly suffer brain damage. Chronic poisoning is of particular concern to sufferers of coronary heart disease, pregnant women, and people with certain hematological disorders. Indoor emission sources, notably fuel-burning heating appliances, cause most unintentional deaths and cases of illness and should be the main focus of concern. Motor vehicle emissions pose a chronic health risk for occupationally exposed groups. Smoking is a major source of personal exposure. Recent exposure to CO is commonly evaluated by measuring blood carboxyhemoglobin levels, which are related to the concentration of atmospheric CO. Monitoring methods are reviewed here, and monitoring is considered in relation to air quality standards and guidelines. Finally, control measures for motor vehicles and indoor heating appliances are suggested. PMID:11048332

Horner, J M

2000-01-01

18

Molecular Structure of carbon monoxide  

NSDL National Science Digital Library

Carbon monoxide is a colorless, flammable gas that is highly toxic due to its ability to out-compete oxygen to form a complex with hemoglobin. When this happens, oxygen transport in the blood is impeded and unconsciousness and death may result. Carbon monoxide is of great industrial importance (e.g., as a fuel or producer gas) in metallurgic processes that isolate various metals from their oxides by reduction with coke. It is also a key intermediate in the catalytic production of various hydrocarbons by industry, including the production of alcohols, Sabatier methanation, and Fischer-Tropsch hydrogenation. Incomplete combustion of fossil fuels (i.e., oxidation of hydrocarbons in a limited supply of oxygen) in automobiles and industrial activity (e.g., energy production) are major anthropogenic sources of CO to the atmosphere. Other sources of carbon monoxide to the atmosphere are the oxidation of methane by the atmospheric oxidant hydroxyl radical and biomass burning (e.g., slash-and-burn agriculture practices).

2006-03-09

19

Environmental Carbon Monoxide Related to Pregnancy Hypertension  

Microsoft Academic Search

Carbon monoxide pollution frequently occurs due to auto exhaust, industrial emissions, and\\/or cigarette smoke. Exogenous and endogenous carbon monoxide affects blood pressure; however, the relation of carbon monoxide exposure to pregnancy hypertension has not been systematically examined. For the present study the authors recruited a total of 2,707 apparently healthy, non-obese, non-smoking mothers, aged between 15 and 40 years, who

Mohsen Vigeh; Masoud Yunesian; Mamak Shariat; Shireen Niroomanesh; Fateme Ramezanzadeh

2011-01-01

20

Carbon monoxide in school buses.  

PubMed

Following an incident in which eight children became ill from carbon monoxide in a school bus, an investigation was made of CO levels in school buses in the Seattle area. The procedure selected for the evaluation was to test a large number of buses at a nearby ski resort. On the day selected for the sampling, over 200 buses arrived, bringing school children from a number of school districts in the Seattle are for skiing lessons. As they arrived, 33 buses were checked immediately to determine in-transit levels of CO. Four of the 33 buses had CO levels in excess of Environmental Protection Agency maximum allowable concentrations for an 8-hr exposure. As the buses sat idling in the parking lot, 65 of them were tested--during the lunch hour when the students returned to the buses to have their lunch and to rest. Two buses had nearly 3 times the concentration of CO permitted by the EPA for a 1-hr exposure. A total of seven buses (10 per cent) had concentrations of CO not permitted by the EPA for more than a 1-hr period. Altogether there were 24 buses (36 per cent) that had levels of CO in excess of EPA standards for an 8-hr exposure. As a result of these determinations and other observations a number of recommendations were made to reduce the hazard of exposure to carbon monoxide in school buses. PMID:1200196

Johnson, C J; Moran, J; Pekich, R

1975-12-01

21

40 CFR 52.376 - Control strategy: Carbon monoxide.  

Code of Federal Regulations, 2013 CFR

...New York-Northern New Jersey-Long Island carbon monoxide attainment area (period 2011 to 2020...Connecticut has committed to: maintain a continuous carbon monoxide monitoring network in each carbon monoxide maintenance area; implement...

2013-07-01

22

40 CFR 86.122-78 - Carbon monoxide analyzer calibration.  

Code of Federal Regulations, 2010 CFR

... 2009-07-01 false Carbon monoxide analyzer calibration...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...Procedures § 86.122-78 Carbon monoxide analyzer calibration. The NDIR carbon monoxide analyzer shall...

2009-07-01

23

Carbon monoxide poisoning from disposable charcoal barbeques.  

PubMed

Carbon monoxide poisoning is a common cause of accidental death and suicide. This article reports 4 cases of carbon monoxide poisoning following the inhalation of fumes from disposable charcoal barbeques in a confined space. All of the cases occurred within a 2-year period in Northern Ireland. PMID:20139755

Lyness, James R; Crane, Jack

2011-09-01

24

Environmental carbon monoxide related to pregnancy hypertension.  

PubMed

Carbon monoxide pollution frequently occurs due to auto exhaust, industrial emissions, and/or cigarette smoke. Exogenous and endogenous carbon monoxide affects blood pressure; however, the relation of carbon monoxide exposure to pregnancy hypertension has not been systematically examined. For the present study the authors recruited a total of 2,707 apparently healthy, non-obese, non-smoking mothers, aged between 15 and 40 years, who had singleton births, and who lived within two miles of the selected air monitoring stations in Tehran, Iran, to study the relation of ambient carbon monoxide to pregnancy hypertension (>140 mmHg systolic and/or >90 mmHg diastolic after the 20th week of gestation). A relatively small but statistically significant elevation in mean postpartum diastolic blood pressure (mean ± SD, 69.5 ± 9.8 mmHg) was observed in the mothers' who were exposed to relatively high ambient carbon monoxide (mean = 14.1 ppm) compared to mothers exposed to lower carbon monoxide (mean = 1.8 ppm) concentrations (mean ± SD, 68.0 ± 8.3 mmHg, p < 0.01). The authors found twice the rate of pregnancy hypertension in the relatively higher carbon monoxide exposed mothers than the mothers with lower exposure (adjusted odds ratio = 2.02, 95% CI 1.35-3.03). Findings of the present study suggest that high level ambient carbon monoxide exposure is associated with pregnancy hypertension. PMID:22185288

Vigeh, Mohsen; Yunesian, Masoud; Shariat, Mamak; Niroomanesh, Shireen; Ramezanzadeh, Fateme

2011-11-30

25

Miniaturized carbon monoxide sonde for atmospheric measurements.  

PubMed

The design and test results of a simple carbon monoxide detector based on the reducing gas detector principle are presented. This instrument has several features which distinguish it from similar carbon monoxide analyzers, all of which contribute to its usefulness on small airborne platforms such as kites, balloons, and light aircraft. Compact size, battery operation, low cost, and light weight are among the most important improvements made over to earlier systems. The instrument fits a package 10 x 20 x 25 cm, has a mass of 2.0 kg, and consumes an average of 20 W of power. This instrument will, therefore, offer a means of incorporating carbon monoxide measurements in recoverable or disposable balloon sondes. The instrument makes an independent measurement of carbon monoxide every 8 s, with a sensitivity of 3 ppbv carbon monoxide (limit of detection for S/N = 3) and a precision of 4%. PMID:9751027

Bognar, J A; Birks, J W

1998-09-15

26

Device for staged carbon monoxide oxidation  

DOEpatents

A method and apparatus for selectively oxidizing carbon monoxide in a hydrogen rich feed stream. The method comprises mixing a feed stream consisting essentially of hydrogen, carbon dioxide, water and carbon monoxide with a first predetermined quantity of oxygen (air). The temperature of the mixed feed/oxygen stream is adjusted in a first the heat exchanger assembly (20) to a first temperature. The mixed feed/oxygen stream is sent to reaction chambers (30,32) having an oxidation catalyst contained therein. The carbon monoxide of the feed stream preferentially absorbs on the catalyst at the first temperature to react with the oxygen in the chambers (30,32) with minimal simultaneous reaction of the hydrogen to form an intermediate hydrogen rich process stream having a lower carbon monoxide content than the feed stream. The elevated outlet temperature of the process stream is carefully controlled in a second heat exchanger assembly (42) to a second temperature above the first temperature. The process stream is then mixed with a second predetermined quantity of oxygen (air). The carbon monoxide of the process stream preferentially reacts with the second quantity of oxygen in a second stage reaction chamber (56) with minimal simultaneous reaction of the hydrogen in the process stream. The reaction produces a hydrogen rich product stream having a lower carbon monoxide content than the process stream. The product stream is then cooled in a third heat exchanger assembly (72) to a third predetermined temperature. Three or more stages may be desirable, each with metered oxygen injection.

Vanderborgh, Nicholas E. (Los Alamos, NM); Nguyen, Trung V. (College Station, TX); Guante, Jr., Joseph (Denver, CO)

1993-01-01

27

Global Atmospheric Carbon Monoxide in 2000 (WMS)  

NSDL National Science Digital Library

This visualization shows global carbon monoxide concentrations at the 500 millibar altitude in the atmosphere from March 1, 2000 through December 31, 2000. Areas in red have 200 parts per billion of carbon monoxide or more at that altitude (around 5,500 meters), while areas in blue are 50 parts per billion or less. Carbon monoxide is an atmospheric pollutant and the highest concentrations come from grassland and forest fires in Africa and South America, although there is evidence that industrial sources may also be a factor. Atmospheric circulation rapidly moves the carbon monoxide to other parts of the world once it has reached this altitude. This data was measured by the MOPITT instrument on the Terra satellite.

Sokolowsky, Eric; Williams, James; Gille, John; Lamarque, Jean-Francois

2004-02-12

28

Infrared Spectra of High Pressure Carbon Monoxide.  

National Technical Information Service (NTIS)

We report infrared (IR) spectroscopic measurements of carbon monoxide (CO) at high pressures. Although CO is one of the simplest heteronuclear diatomic molecules, it displays surprisingly complex behavior at high pressures and has been the subject of seve...

W. J. Evans M. J. Lipp H. E. Lorenzana

2001-01-01

29

Houseboats Can Carry Hidden Carbon Monoxide Dangers  

MedlinePLUS

... These hazardous conditions were exacerbated when the drive engines were operating, placing employees who worked on or ... to carbon monoxide emissions from generators, stern-drive engines, inboard and outboard engines and personal watercraft. "Controlling ...

30

Carbon Monoxide Poisonings May Rise During Storms  

MedlinePLUS

... Study found indoor use of generators, even deep snow can lead to lethal buildup of the odorless ... This occurs when car tailpipes become clogged with snow. "Lethal concentrations of carbon monoxide can form in ...

31

Hyperbaric Oxygen for Acute Carbon Monoxide Poisoning  

Microsoft Academic Search

Background Patients with acute carbon monoxide poisoning commonly have cognitive sequelae. We conducted a double-blind, randomized trial to evaluate the effect of hyperbaric-oxygen treatment on such cognitive sequelae. Methods We randomly assigned patients with symptomatic acute carbon monoxide poisoning in equal proportions to three chamber sessions within a 24-hour period, consisting of either three hyperbaric-oxygen treatments or one normobaric-oxygen treatment

Lindell K. Weaver; Ramona O. Hopkins; Karen J. Chan; Susan Churchill; C. Gregory Elliott; Terry P. Clemmer; James F. Orme; Frank O. Thomas; Alan H. Morris

2002-01-01

32

Management of carbon monoxide poisoning.  

PubMed

Carbon monoxide poisoning is a major cause of illness and death in the United States. Most cases result from exposure to the internal combustion engine and to stoves burning fossil fuels. Most cases of accidental exposure are preventable if proper precautions are taken; however, when cases arise, their presenting signs and symptoms are nonspecific and often lead to a misdiagnosis resembling a flu-like viral illness. As a result, the incidence of acute CO poisoning is underestimated. The effects of CO poisoning are due to tissue hypoxia, with the CNS and the heart being the most susceptible target organs due to their high oxygen needs. Prolonged hypoxia due to high CO levels may lead to cardiac arrhythmias or arrest (or both) and a variety of neurologic sequelae. Treatment is directed toward the relief of tissue hypoxia and the removal of CO from the body. Severity of poisoning can be divided into three levels based on CO levels in the blood. Administration of normobaric 100 percent oxygen is the therapy of choice for most cases, while hyperbaric oxygen therapy is reserved for severe poisonings. PMID:2403894

Ilano, A L; Raffin, T A

1990-01-01

33

Catalytic hydrogenation of carbon monoxide  

SciTech Connect

This project is focused on developing strategies to accomplish the reduction and hydrogenation of carbon monoxide to produce organic oxygenates at mild conditions. Our approaches to this issue are based on the recognition that rhodium macrocycles have unusually favorable thermodynamic values for producing a series of intermediate implicated in the catalytic hydrogenation of CO. Observations of metalloformyl complexes produced by reactions of H{sub 2} and CO, and reductive coupling of CO to form metallo {alpha}-diketone species have suggested a multiplicity of routes to organic oxygenates that utilize these species as intermediates. Thermodynamic and kinetic-mechanistic studies are used in constructing energy profiles for a variety of potential pathways, and these schemes are used in guiding the design of new metallospecies to improve the thermodynamic and kinetic factors for individual steps in the overall process. Variation of the electronic and steric effects associated with the ligand arrays along with the influences of the reaction medium provide the chemical tools for tuning these factors. Emerging knowledge of the factors that contribute to M-H, M-C and M-O bond enthalpies is directing the search for ligand arrays that will expand the range of metal species that have favorable thermodynamic parameters to produce the primary intermediates for CO hydrogenation. Studies of rhodium complexes are being extended to non-macrocyclic ligand complexes that emulate the favorable thermodynamic features associated with rhodium macrocycles, but that also manifest improved reaction kinetics. Multifunctional catalyst systems designed to couple the ability of rhodium complexes to produce formyl and diketone intermediates with a second catalyst that hydrogenates these imtermediates are promising approaches to accomplish CO hydrogenation at mild conditions.

Wayland, B.B.

1992-12-01

34

CARBON MONOXIDE AND THE NERVOUS SYSTEM  

EPA Science Inventory

Carbon monoxide (CO) is a colorless, tasteless, odorless, and non-irritating gas formed when carbon in fuel is not burned completely. It enters the bloodstream through the lungs and attaches to hemoglobin (Hb), the body's oxygen carrier, forming carboxyhemoglobin (COHb) and there...

35

Enhanced carbon monoxide utilization in methanation process  

DOEpatents

Carbon monoxide - containing gas streams are passed over a catalyst to deposit a surface layer of active surface carbon thereon essentially without the formation of inactive coke. The active carbon is subsequently reacted with steam or hydrogen to form methane. Surprisingly, hydrogen and water vapor present in the feed gas do not adversely affect CO utilization significantly, and such hydrogen actually results in a significant increase in CO utilization.

Elek, Louis F. (Peekskill, NY); Frost, Albert C. (Congers, NY)

1984-01-01

36

Microwave measurements of carbon monoxide on titan.  

PubMed

The ratio of the flux density of Titan was measured in two 200-megahertz bands, one centered on the (1-0) rotation line of carbon monoxide at 115.3 gigahertz and the other 2600 megahertz lower. The measurements were made with a complex-correlation technique on the new millimeter-wavelength interferometer at the Owens Valley Radio Observatory, Big Pine, California. The excess flux in the carbon monoxide band is interpreted as a strong detection of carbon monoxide and a mixing ratio, assumed constant, of 6 x 10(-5). The brightness temperature of Titan at 112.6 gigahertz is 69 +/- 10 kelvins, consistent with atmospheric emission from just below the tropopause. PMID:17829888

Muhleman, D O; Berge, G L; Clancy, R T

1984-01-27

37

Carbon monoxide poisoning secondary to hookah smoking.  

PubMed

Hookah smoking, at one time confined to North Africa, the eastern Mediterranean region, the Arabian peninsula, and Southeast Asia, has begun to spread throughout the world. As some practices of eastern and Arab cultures reach the United States, the number of people using hookah on an experimental or regular basis has increased. Carbon monoxide poisoning can be a common adverse effect, possibly undetected by physicians, in hookah smokers. The authors report a case of carbon monoxide poisoning secondary to smoking tobacco through a hookah. PMID:23055468

Ashurst, John V; Urquhart, Megan; Cook, Matthew D

2012-10-01

38

Carbon Monoxide: An Agent of Change  

NSDL National Science Digital Library

This problem-based learning module places learners in the role of researchers analyzing carbon monoxide's environmental impact. Both vehicle emissions and biomass burning are cited as events producing carbon monoxide that impact the environment. Instructions for accessing NASA data from four different sources are provided along with suggested resources and investigations for classroom use. This module was developed to be used in the Earth System Science Education Alliance (ESSEA) courses for middle and high school teachers and is also available to teachers to adapt for general classroom use.

39

[Carbon monoxide metabolism by photosynthetic bacteria]. Progress report  

SciTech Connect

Research continued on the metabolism of carbon monoxide by Rhodospirillum rubrum. This report discusses progress on the activity, induction, inhibition, and spectroscopic analysis of the enzyme Carbon Monoxide Dehydrogenase. (CBS)

Not Available

1989-12-31

40

40 CFR 86.522-78 - Carbon monoxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...Zero the carbon monoxide analyzer with either zero grade air or zero grade nitrogen...calibrated. (1) Adjust the analyzer to optimize performance...Zero the carbon monoxide analyzer with either zero grade air or zero grade...

2013-07-01

41

40 CFR 90.317 - Carbon monoxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...Zero the carbon monoxide analyzer with either purified synthetic air or zero-grade nitrogen... (1) Adjust the analyzer to optimize performance...Zero the carbon monoxide analyzer with either purified synthetic air or zero-grade...

2013-07-01

42

40 CFR 91.317 - Carbon monoxide analyzer calibration.  

Code of Federal Regulations, 2013 CFR

...Zero the carbon monoxide analyzer with either purified synthetic air or zero-grade nitrogen... (1) Adjust the analyzer to optimize performance...Zero the carbon monoxide analyzer with either purified synthetic air or zero-grade...

2013-07-01

43

40 CFR 52.2089 - Control strategy: carbon monoxide.  

Code of Federal Regulations, 2013 CFR

...committed to year round carbon monoxide monitoring at the East Providence...Photochemical Assessment Monitoring Station (PAMS) site...downtown Providence CO monitoring if criteria specified...that project-level carbon monoxide...

2013-07-01

44

40 CFR 52.2089 - Control strategy: carbon monoxide.  

Code of Federal Regulations, 2010 CFR

...committed to year round carbon monoxide monitoring at the East Providence...Photochemical Assessment Monitoring Station (PAMS) site...downtown Providence CO monitoring if criteria specified...that project-level carbon monoxide...

2009-07-01

45

40 CFR 52.2089 - Control strategy: carbon monoxide.  

Code of Federal Regulations, 2010 CFR

...committed to year round carbon monoxide monitoring at the East Providence...Photochemical Assessment Monitoring Station (PAMS) site...downtown Providence CO monitoring if criteria specified...that project-level carbon monoxide...

2010-07-01

46

Evaluation of Personal Carbon Monoxide Monitors  

Microsoft Academic Search

Carbon monoxide is a chemical asphyxiant found in many working areas and whose toxicity has been known for a long time. It is emitted by incomplete combustion of any organic material, and high concentrations are often measured in metal industries. Despite the fact that it is a well known contaminant, measurement techniques normally used in industrial hygiene in Québec do

Brigitte Roberge; Nicole Goyer

1993-01-01

47

DIRECT CARBON MONOXIDE PHOTOPRODUCTION FROM PLANT MATTER  

EPA Science Inventory

Initial studies to quantify direct carbon monoxide photoproduction from several plant species are reported. n addition to measuring CO emissions from live plant leaves, emission rates from dead leaf matter were also determined. enescent leaf matter photoproduced CO at rates that ...

48

Methane and Carbon Monoxide in Snow  

Microsoft Academic Search

Freshly fallen snow, gathered at Mt. Hood (Oregon), was found to contain a lot of carbon monoxide (CO) but no methane (CHâ). This result will be established in the paper and used to show that the atmospheric concentration of methane many hundreds of years ago was less than half what it is today.Rasmussen and Khalil have recently established that the

R. A. Rasmussen; M. A. K. Khalil; S. D. Hoyt

1982-01-01

49

Neurological manifestation of carbon monoxide poisoning.  

PubMed Central

The clinical signs and post-mortem findings in a case of carbon monoxide poisoning are described, and correlated with the computer tomographic (CT) scan appearances. The value of serial CT scanning as a diagnostic tool is highlighted. Images Figure 1 Figure 2

Hart, I. K.; Kennedy, P. G.; Adams, J. H.; Cunningham, N. E.

1988-01-01

50

Mars in situ propellants: Carbon monoxide and oxygen ignition experiments  

Microsoft Academic Search

Carbon monoxide and oxygen were tested in a standard spark-torch igniter to identify the ignition characteristics of this potential Mars in situ propellant combination. The ignition profiles were determined as functions of mixture ratio, amount of hydrogen added to the carbon monoxide, and oxygen inlet temperature. The experiments indicated that the carbon monoxide and oxygen combination must have small amounts

D. L. Linne; J. Roncace; M. F. Groth

1990-01-01

51

Fermentative production of ethanol from carbon monoxide.  

PubMed

'Too much Carbon Monoxide for me to bear…' are the opening lyrics of the CAKE song Carbon Monoxide (from their 2004 album Pressure Chief), and while this may be the case for most living organisms, several species of bacteria both thrive on this otherwise toxic gas, and metabolize it for the production of fuels and chemicals. Indeed CO fermentation offers the opportunity to sustainably produce fuels and chemicals without impacting the availability of food resources or even farm land. Mounting commercial interest in the potential of this process has in turn triggered greater scrutiny of the molecular and genetic basis for CO metabolism, as well as the challenges associated with the implementation and operation of gas fermentation at scale. PMID:21353524

Köpke, Michael; Mihalcea, Christophe; Bromley, Jason C; Simpson, Séan D

2011-06-01

52

Sensorineural Hearing Loss following Carbon Monoxide Poisoning  

PubMed Central

A case study is presented of a 17-year-old male who sustained an anoxic brain injury and sensorineural hearing loss secondary to carbon monoxide poisoning. Audiological data is presented showing a slightly asymmetrical hearing loss of sensorineural origin and mild-to-severe degree for both ears. Word recognition performance was fair to poor bilaterally for speech presented at normal conversational levels in quiet. Management considerations of the hearing loss are discussed.

Pillion, Joseph P.

2012-01-01

53

The carbon monoxide abundance in interstellar clouds  

NASA Technical Reports Server (NTRS)

The steady-state abundance of carbon monoxide in interstellar clouds is calculated as a function of optical depth, density, and temperature. The molecular reactions which lead to CO can be initiated by the following ion-molecule reactions: H(+) + O yields O(+) + H, C(+) + H2 yields CH2(+) + a photon, and H3(+) + C and O. As the ultraviolet radiation field is attenuated, C(+) is transformed primarily into CO and C I. There are characteristic column densities for the transition to CO corresponding to the optical depths for attenuating this field at different wavelengths. For thick, low-temperature clouds the attenuation of the fields which ionize carbon, sulfur, and heavy metals is important for CO production initiated by H3(+). Complete conversion to CO does not necessarily occur, and considerable neutral carbon may be expected even in optically thick clouds. Comparison of integrated column densities of CO with extinction are in reasonable agreement with observations.

Langer, W.

1976-01-01

54

Carbon monoxide and COHb concentration in blood in various circumstances  

Microsoft Academic Search

On the basis of known medical experiments we find out the correlation between the concentration of carbon monoxide (CO) in inhaling air and the concentration of carboxihemoglobyne (COHb) in human blood. All internal combustion engines produce exhaust gases containing noxious compounds: carbon monoxide, nitrogen oxides (NOx), carbon oxides (CxHy) and smoke. In a living room is important the smoke of

Jurij Modic

2003-01-01

55

Carbon Monoxide Dehydrogenase Activity in Bradyrhizobium japonicum  

PubMed Central

Bradyrhizobium japonicum strain 110spc4 was capable of chemolithoautotrophic growth with carbon monoxide (CO) as a sole energy and carbon source under aerobic conditions. The enzyme carbon monoxide dehydrogenase (CODH; EC 1.2.99.2) has been purified 21-fold, with a yield of 16% and a specific activity of 58 nmol of CO oxidized/min/mg of protein, by a procedure that involved differential ultracentrifugation, anion-exchange chromatography, hydrophobic interaction chromatography, and gel filtration. The purified enzyme gave a single protein and activity band on nondenaturing polyacrylamide gel electrophoresis and had a molecular mass of 230,000 Da. The 230-kDa enzyme was composed of large (L; 75-kDa), medium (M; 28.4-kDa), and small (S; 17.2-kDa) subunits occurring in heterohexameric (LMS)2 subunit composition. The 75-kDa polypeptide exhibited immunological cross-reactivity with the large subunit of the CODH of Oligotropha carboxidovorans. The B. japonicum enzyme contained, per mole, 2.29 atoms of Mo, 7.96 atoms of Fe, 7.60 atoms of labile S, and 1.99 mol of flavin. Treatment of the enzyme with iodoacetamide yielded di(carboxamidomethyl)molybdopterin cytosine dinucleotide, identifying molybdopterin cytosine dinucleotide as the organic portion of the B. japonicum CODH molybdenum cofactor. The absorption spectrum of the purified enzyme was characteristic of a molybdenum-containing iron-sulfur flavoprotein.

Lorite, Maria J.; Tachil, Jorg; Sanjuan, Juan; Meyer, Ortwin; Bedmar, Eulogio J.

2000-01-01

56

Carbon monoxide adsorption on beryllium surfaces  

NASA Astrophysics Data System (ADS)

Density functional calculations are here carried out to study the carbon monoxide molecule adsorption on pristine, hydrogenated and hydroxylated beryllium Be (0001) surfaces. The adsorption energies and structures, the activation barriers to molecular adsorption and dissociation are calculated. These reactions are described in terms of potential energy surfaces and electronic density of states. The quantum results are discussed along two directions: the beryllium surface reactivity in the domain of nuclear fusion devices and the possible usage of beryllium as a catalyst of Fischer-Tropsch-type synthesis.

Allouche, A.

2013-02-01

57

Global decrease in atmospheric carbon monoxide concentration  

NASA Astrophysics Data System (ADS)

CARBON monoxide plays an important role in the oxidizing capacity of the Earth's atmosphere, and may thereby indirectly affect the concentrations of many man-made and natural trace gases, which in turn affect climate, atmospheric chemistry and the ozone layer1. CO is produced in the atmosphere by the oxidation of methane and other hydrocarbons, and is released into the atmosphere from automobiles, agricultural waste and the burning of savanna1-4. Recent estimates1 show that human activities such as these are presently responsible for more than half the annual emissions of CO. During the 1980s there was evidence that atmospheric CO concentrations were increasing at ~1.2+/-0.6% per year, leading to feedbacks that could amplify global warming. Here we present a continuation of these measurements which show that from 1988 to 1992 global CO concentrations have started to decline rapidly at a rate of about -2.6+/-0.8% per year. A recent study5 has verified our findings with data from the past 3-4 years. The rate of decrease is particularly rapid in the Southern Hemisphere; we hypothesize that this may reflect a reduction in tropical biomass burning. The total amount of carbon monoxide in the atmosphere is less now than a decade ago.

Khalil, M. A. K.; Rasmussen, R. A.

1994-08-01

58

40 CFR 52.269 - Control strategy and regulations: Photochemical oxidants (hydrocarbons) and carbon monoxide.  

Code of Federal Regulations, 2013 CFR

...oxidants (hydrocarbons) and carbon monoxide. 52.269 Section...oxidants (hydrocarbons) and carbon monoxide. (a) The...oxidants (hydrocarbons) and carbon monoxide in the San Francisco...The revocation of Rule 412, Organic Liquid Loading, is...

2013-07-01

59

Real World of Industrial Chemistry: Organic Chemicals from Carbon Monoxide.  

ERIC Educational Resources Information Center

Carbon Monoxide obtained from coal may serve as the source for a wide variety of organic compounds. Several of these compounds are discussed, including phosgene, benzaldehyde, methanol, formic acid and its derivatives, oxo aldehydes, acrylic acids, and others. Commercial reactions of carbon monoxide are highlighted in a table. (JN)

Kolb, Kenneth E.; Kolb, Doris

1983-01-01

60

Calculating carbon monoxide emissions from vehicle traffic in Phoenix  

Microsoft Academic Search

Ambient carbon monoxide concentrations in the Phoenix area have exceeded the standard of 9 ppm for an 8-hour average. Like many urban areas in the United States, Phoenix did not meet the December 31, 1987 deadline for attainment of the carbon monoxide (CO) and ozone National Ambient Air Quality Standard (NAAQS) as mandated in the Clean Air Act. Elevated CO

M. C. Dudik; R. G. Ireson

1988-01-01

61

Carbon Monoxide: Its Role in Photochemical Smog Formation  

Microsoft Academic Search

The photochemistry of trace amounts of isobutene and oxides of nitrogen in an atmosphere of air was studied both in the presence and in the absence of small amounts of carbon monoxide. Carbon monoxide accelerates the reaction as measured by nitric oxide oxidation or ozone formation. This finding has relevance to photochemical smog formation.

Karl Westberg; Norman Cohen; K. W. Wilson

1971-01-01

62

Carbon monoxide and exercise tolerance in chronic bronchitis and emphysema  

Microsoft Academic Search

The effects of carbon monoxide on exercise tolerance as assessed by the distance walked in 12 minutes were studied in 15 patients with severe chronic bronchitis and emphysema (mean forced expiratory volume in one second 0.56 1, mean forced vital capacity 1.54 1). Each subject walked breathing air and oxygen before and after exposure to sufficient carbon monoxide to raise

P M Calverley; R J Leggett; D C Flenley

1981-01-01

63

Real time carbon monoxide measurements from 56 UK homes  

Microsoft Academic Search

This paper reports results from the monitoring part of a recent UK Department of Health funded project investigating carbon monoxide (CO) levels in homes during the winter of 2002\\/2003. In all, 56 homes were monitored for carbon monoxide in 3 cities across the UK. The homes were selected as part of the UK government Warm Front evaluation programme (aimed at

Croxford B; Hutchinson E; Leonardi GS; McKenna L; Riddington M; Volans G

64

Fatal carbon monoxide intoxication after acetylene gas welding of pipes.  

PubMed

Acetylene gas welding of district heating pipes can result in exposure to high concentrations of carbon monoxide. A fatal case due to intoxication is described. Measurements of carbon monoxide revealed high levels when gas welding a pipe with closed ends. This fatality and these measurements highlight a new hazard, which must be promptly prevented. PMID:23307861

Antonsson, Ann-Beth; Christensson, Bengt; Berge, Johan; Sjögren, Bengt

2013-06-01

65

Search of medical literature for indoor carbon monoxide exposure  

SciTech Connect

This report documents a literature search on carbon monoxide. The search was limited to the medical and toxicological databases at the National Library of Medicine (MEDLARS). The databases searched were Medline, Toxline and TOXNET. Searches were performed using a variety of strategies. Combinations of the following keywords were used: carbon, monoxide, accidental, residential, occult, diagnosis, misdiagnosis, heating, furnace, and indoor. The literature was searched from 1966 to the present. Over 1000 references were identified and summarized using the following abbreviations: The major findings of the search are: (1) Acute and subacute carbon monoxide exposures result in a large number of symptoms affecting the brain, kidneys, respiratory system, retina, and motor functions. (2) Acute and subacute carbon monoxide (CO) poisonings have been misdiagnosed on many occasions. (3) Very few systematic investigations have been made into the frequency and consequences of carbon monoxide poisonings.

Brennan, T.; Ivanovich, M.

1995-12-01

66

Process for producing carbon monoxide and hydrogen from methanol  

SciTech Connect

A process is described for producing carbon monoxide and hydrogen which comprises contacting methanol vapor at a temperature of 200 degrees to 300 degrees C with an indirectly heated zinc containing catalyst to obtain an effluent gas in which the components of carbon monoxide and hydrogen constitute at least 90% by volume of said gas. At least a part of the impurities from said effluent gas are removed and said effluent gas is deparated into its carbon monoxide and hydrogen components by adsorption. The effluent gas can be separated into its carbon monoxide and hydrogen components by use of a plurality of adsorbers containing zeolite-type molecular sieve material where the zeolite is substantially permeable to hydrogen but sorbs carbon monoxide.

Jockel, H.; Marschner, F.; Moller, F.W.; Mortel, H.

1982-02-23

67

Carbon monoxide exposure of subjects with documented cardiac arrhythmias  

SciTech Connect

The impact of low-level carbon monoxide exposure on ventricular arrhythmia frequency in patients with ischemic heart disease has not been thoroughly studied. The issue is of concern because of the potential proarrhythmic effect of carbon monoxide in patients with ischemic heart disease. We studied 30 subjects with well-documented coronary artery disease who had an average of at least 30 ventricular ectopic beats per hour over a 20-hour monitoring interval. By using appropriate inclusion and exclusion criteria, subjects were selected and enrolled in a randomized double-blind study to determine the effects of carbon monoxide exposure on ventricular arrhythmia frequency at rest, during exercise, and during ambulatory activities. The carbon monoxide exposure was designed to result in 3% or 5% carboxyhemoglobin levels, as measured by gas chromatography. The carbon monoxide exposure protocol produced target levels in 60 minutes, and the levels were maintained for an additional 90 minutes to provide adequate time to assess the impact of carbon monoxide on the frequency of ventricular ectopic beats. The data on total and repetitive ventricular arrhythmias were analyzed for seven specific time intervals: (1) two hours before carbon monoxide exposure; (2) during the two-hour carbon monoxide or air exposure; (3) during a two-hour rest period; (4) during an exercise period; (5) during an exercise recovery period; (6) six hours after carbon monoxide or air exposure; and (7) approximately 10 hours after exposure, or the remaining recording interval on the Holter monitor. There was no increase in ventricular arrhythmia frequency after carbon monoxide exposure, regardless of the level of carboxyhemoglobin or the type of activity.

Chaitman, B.R.; Dahms, T.E.; Byers, S.; Carroll, L.W.; Younis, L.T.; Wiens, R.D. (St. Louis Univ. School of Medicine, MO (United States))

1992-09-01

68

Reduction of carbon monoxide. Past research summary  

SciTech Connect

Research programs for the year on the preparation, characterization, and reactions of binuclear tantalum complexes are described. All evidence to date suggest the following of these dimeric molecules: (1) the dimer does not break into monomers under mild conditions; (2) intermolecular hydride exchange is not negligible, but it is slow; (3) intermolecular non-ionic halide exchange is fast; (4) the ends of the dimers can rotate partially with respect to one another. The binuclear tantalum hydride complexes were found to react with carbon monoxide to give a molecule which is the only example of reduction of CO by a transition metal hydride to give a complex containing a CHO ligand. Isonitrides also reacted in a similar manner with dimeric tantalum hydride. (ATT)

Schrock, R.R.

1981-10-01

69

Carbon monoxide binding to iron porphyrins.  

PubMed Central

The carbon monoxide affinities of iron complexes of meso-tetra (alpha, alpha, alpha, alpha-o-pivalamidophenyl)porphyrin (the "picket fence" porphyrin) and of a "picket fence" porphyrin derivative with an appended axial base have been measured in solution and compared with the CO affinities of various hemoproteins. The model complexes bind CO with much greater affinity than normal hemoproteins; the role of the steric bulk of distal residues in lowering the CO affinities of the hemoproteins is discussed. The significance of this lowered CO affinity is described with regard to endogenous CO. A discussion of mutant hemoglobins lacking distal residues that sterically inhibit the binding of CO is presented. The use of pressure units versus concentration units in equilibrium expressions is analyzed.

Collman, J P; Brauman, J I; Doxsee, K M

1979-01-01

70

Analysis of GASP carbon monoxide data  

NASA Technical Reports Server (NTRS)

Atmospheric carbon monoxide in the upper troposphere and lower stratosphere for the period March 1977 through October 1978 was analyzed. The CO data are summarized and the distribution and variations in space and time of this gas are presented. The data show that the CO mixing ratios are higher in the troposphere than those in the stratosphere. In the Northern Hemisphere the highest value of CO mixing ratio occurs in spring, although more data are needed to verify these findings. Correlation coefficients among CO, O3, air temperature (T) and winds were calculated for different regions under different seasons. It was found that the CO correlates negatively with O3 above 20 degrees latitude and positively below that latitude. Case studies using the data of CO, O3, and T measured simultaneously were performed. Discussions and suggestions are made. Ozone data on seasonal basis is also summarized.

Wu, M. F.

1981-01-01

71

A personal miner's carbon monoxide alarm  

SciTech Connect

Underground miners may be exposed to hazardous quantities of toxic gases, such as carbon monoxide (CO), generated from mine fires or explosions. Every underground miner is required to carry a filter self-rescuer (FSR), which when operated will remove CO from the miner's breathing air. In addition, every underground miner must have a self-contained self-rescuer(SCSR) near the worksite that will supply breathing oxygen. In many situations, miners do not know when to don either rescuer since they do not know if there is a fire in the mine, nor do they carry instrumentation necessary for the detection of the toxic, colorless, and odorless fire product CO. If each miner carried a personal CO alarm, which would respond to high concentrations of CO, the miner would then be alerted when to don either the FSR or SCSR and exit the mine. The authors report on the development of a prototype personal miner's CO alarm called PEMCOAL.

Chilton, J.E.; Carpenter, C.R.

1989-01-01

72

Airborne intercomparisons of carbon monoxide measurement techniques  

NASA Technical Reports Server (NTRS)

Results from an airborne intercomparison of techniques to measure tropospheric levels of carbon monoxide (CO) are discussed. The intercomparison was conducted as part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and included a laser differential absorption method and two grab sample/gas chromatograph methods. Measurements were obtained during approximately 90 flight hours, during which the CO mixing ratios ranged from about 60 to 140 ppbv. The level of agreement observed for the ensemble of measurements was well within the overall accuracy stated for each instrument. The correlation observed between the measurements from the respective pairs of instruments ranged from 0.85 to 0.98, with no evidence for the presence of either a constant or proportional bias between any of the instruments.

Hoell, James M., Jr.; Gregory, Gerald L.; Mcdougal, David S.; Sachse, Glen W.; Hill, Gerald F.; Condon, Estelle P.

1987-01-01

73

Overabundance of carbon monoxide in calorimetry tests  

SciTech Connect

The amount of carbon monoxide recovered from calorimetry tests of high explosives is far larger than the amount predicted by equilibrium calculations. The present kinetics study of PETN [(nitro(oxy)methyl]-propanediol dinitrate) has revealed that the cooling of the calorimetry bomb after detonation of a PETN sample sufficiently slows those reactions that would otherwise lead to equilibrium so that these reactions are effectively frozen in the time scale of recovery of detonation products. Among these reactions, those that can create CH{sub 4} are the most important ones. Their rates are generally slow at all temperatures relevant to calorimetry tests. This and the slowing down of a reaction, CO + H{sub 2}O {yields} H{sub 2} + CO{sub 2} at temperatures below 1500 K are the main caus of the freeze-out of CO. A possible slow rate of the soot formation (i.e., condensed carbon) is not responsible for it. The sensitivity of the present result to the cooling rate of the detonation products and to free radicals is also examined. 10 refs., 5 figs., 2 tabs.

Ree, F.H.; Pitz, W.J.; Thiel, M. van; Souers, P.C. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States)

1996-04-04

74

Methane and carbon monoxide in snow  

SciTech Connect

Freshly fallen snow, gathered at Mt. Hood (Oregon), was found to contain a lot of carbon monoxide (CO) but no methane (CH/sub 4/). This result will be established in the paper and used to show that the atmospheric concentration of methane many hundreds of years ago was less than half what it is today.Rasmussen and Khalil have recently established that the concentration of CH/sub 4/ has been increasing in the earth's atmosphere, at least over the past several years, and that this increase is most likely caused by human activities. If CH/sub 4/ continues to increase, it may warm the earth's atmosphere and thereby disturb the natural environment on a global scale, as well as alter the global balance of ozone in the troposphere and the stratosphere. In terms of global warming, CH/sub 4/ acts similarly to the much publicized effects of increasing carbon dioxide (CO/sub 2/) on the earth's environment. It is, therefore, of considerable important to determine the amount of CH/sub 4/ which existed hundreds of years ago before human activities had any perceptible effect on its atmospheric concentration.

Rasmussen, R.A.; Khalil, M.A.K.; Hoyt, S.D.

1982-02-01

75

Encapsulation kinetics and dynamics of carbon monoxide in clathrate hydrate.  

PubMed

Carbon monoxide clathrate hydrate is a potentially important constituent in the solar system. In contrast to the well-established relation between the size of gaseous molecule and hydrate structure, previous work showed that carbon monoxide molecules preferentially form structure-I rather than structure-II gas hydrate. Resolving this discrepancy is fundamentally important to understanding clathrate formation, structure stabilization and the role the dipole moment/molecular polarizability plays in these processes. Here we report the synthesis of structure-II carbon monoxide hydrate under moderate high-pressure/low-temperature conditions. We demonstrate that the relative stability between structure-I and structure-II hydrates is primarily determined by kinetically controlled cage filling and associated binding energies. Within hexakaidecahedral cage, molecular dynamic simulations of density distributions reveal eight low-energy wells forming a cubic geometry in favour of the occupancy of carbon monoxide molecules, suggesting that the carbon monoxide-water and carbon monoxide-carbon monoxide interactions with adjacent cages provide a significant source of stability for the structure-II clathrate framework. PMID:24936712

Zhu, Jinlong; Du, Shiyu; Yu, Xiaohui; Zhang, Jianzhong; Xu, Hongwu; Vogel, Sven C; Germann, Timothy C; Francisco, Joseph S; Izumi, Fujio; Momma, Koichi; Kawamura, Yukihiko; Jin, Changqing; Zhao, Yusheng

2014-01-01

76

Encapsulation kinetics and dynamics of carbon monoxide in clathrate hydrate  

PubMed Central

Carbon monoxide clathrate hydrate is a potentially important constituent in the solar system. In contrast to the well-established relation between the size of gaseous molecule and hydrate structure, previous work showed that carbon monoxide molecules preferentially form structure-I rather than structure-II gas hydrate. Resolving this discrepancy is fundamentally important to understanding clathrate formation, structure stabilization and the role the dipole moment/molecular polarizability plays in these processes. Here we report the synthesis of structure-II carbon monoxide hydrate under moderate high-pressure/low-temperature conditions. We demonstrate that the relative stability between structure-I and structure-II hydrates is primarily determined by kinetically controlled cage filling and associated binding energies. Within hexakaidecahedral cage, molecular dynamic simulations of density distributions reveal eight low-energy wells forming a cubic geometry in favour of the occupancy of carbon monoxide molecules, suggesting that the carbon monoxide–water and carbon monoxide–carbon monoxide interactions with adjacent cages provide a significant source of stability for the structure-II clathrate framework.

Zhu, Jinlong; Du, Shiyu; Yu, Xiaohui; Zhang, Jianzhong; Xu, Hongwu; Vogel, Sven C.; Germann, Timothy C.; Francisco, Joseph S.; Izumi, Fujio; Momma, Koichi; Kawamura, Yukihiko; Jin, Changqing; Zhao, Yusheng

2014-01-01

77

Sequestration and selective oxidation of carbon monoxide on graphene edges  

Microsoft Academic Search

The versatility of carbon nanostructures makes them attractive as possible catalytic materials, as they can be synthesized in various shapes and chemically modified by doping, functionalization, and the creation of defects in the nanostructure. In this work, we consider the carbon-mediated partial sequestration and selective oxidation of carbon monoxide (CO), an important problem in environmental chemistry and energy conversion. Using

Sujata Paul; Erik E. Santiso; Marco B. Nardelli

2008-01-01

78

Mars in situ propellants: Carbon monoxide and oxygen ignition experiments  

NASA Technical Reports Server (NTRS)

Carbon monoxide and oxygen were tested in a standard spark-torch igniter to identify the ignition characteristics of this potential Mars in situ propellant combination. The ignition profiles were determined as functions of mixture ratio, amount of hydrogen added to the carbon monoxide, and oxygen inlet temperature. The experiments indicated that the carbon monoxide and oxygen combination must have small amounts of hydrogen present to initiate reaction. Once the reaction was started, the combustion continued without the presence of hydrogen. A mixture ratio range was identified where ignition occurred, and this range varied with the oxygen inlet temperature.

Linne, Diane L.; Roncace, James; Groth, Mary F.

1990-01-01

79

Syncope Associated with Carbon Monoxide Poisoning due to Narghile Smoking  

PubMed Central

Narghile smoking is a traditional method of tobacco use, and it has been practiced extensively for 400 years. Traditionally, narghile smoking is a matter of culture mainly in Middle East, Asia, and Africa. In recent years, its use as a social activity has increased worldwide, especially among young people. Narghile smoking is an unusual cause of carbon monoxide poisoning. Narghile smoking, compared to cigarette smoking, can result in more smoke exposure and greater levels of carbon monoxide. We present an acute syncope case of a 19-year-old male patient who had carbon monoxide poisoning after narghile smoking.

Ozkan, Seda; Ozturk, Tayfun; Ozmen, Yavuz; Durukan, Polat

2013-01-01

80

Mars in situ propellants: Carbon monoxide and oxygen ignition experiments  

SciTech Connect

Carbon monoxide and oxygen were tested in a standard spark-torch igniter to identify the ignition characteristics of this potential Mars in situ propellant combination. The ignition profiles were determined as functions of mixture ratio, amount of hydrogen added to the carbon monoxide, and oxygen inlet temperature. The experiments indicated that the carbon monoxide and oxygen combination must have small amounts of hydrogen present to initiate reaction. Once the reaction was started, the combustion continued without the presence of hydrogen. A mixture ratio range was identified where ignition occurred, and this range varied with the oxygen inlet temperature.

Linne, D.L.; Roncace, J.; Groth, M.F.

1990-07-01

81

Carbon monoxide sensor and method of use thereof  

DOEpatents

Carbon monoxide sensors suitable for use in hydrogen feed streams and methods of use thereof are disclosed. The sensors are palladium metal/insulator/semiconductor (Pd-MIS) sensors which may possess a gate metal layer having uniform, Type 1, or non-uniform, Type 2, film morphology. Type 1 sensors display an increased sensor response in the presence of carbon monoxide while Type 2 sensors display a decreased response to carbon monoxide. The methods and sensors disclosed herein are particularly suitable for use in proton exchange membrane fuel cells (PEMFCs).

McDaniel; Anthony H. (Livermore, CA), Medlin; J. Will (Boulder, CO), Bastasz; Robert J. (Livermore, CA)

2007-09-04

82

Quantum molecular dynamic simulations of warm dense carbon monoxide.  

PubMed

Using quantum molecular dynamic simulations, we have studied the thermophysical properties of warm dense carbon monoxide under extreme conditions. The principal Hugoniot pressure up to 286 GPa, which is derived from the equation of state, is calculated and compared with available experimental and theoretical data. The chemical decomposition of carbon monoxide has been predicted at 8 GPa by means of pair correlation function and the charge density distribution. Based on Kubo-Greenwood formula, the dc electrical conductivity and the optical reflectivity are determined, and the nonmetal-metal transition for shock compressed carbon monoxide is observed around 40 GPa. PMID:21842937

Zhang, Yujuan; Wang, Cong; Li, Dafang; Zhang, Ping

2011-08-14

83

40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.  

Code of Federal Regulations, 2013 CFR

...dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers. (b) The use of linearizing circuits is permitted. (c) The minimum water rejection...

2013-07-01

84

Carbon Monoxide Poisoning - Multiple Languages: MedlinePlus  

MedlinePLUS

... Hmoob) Khmer (Khmer) Kurdish (?????) Laotian (Lao) Portuguese (português) Somali (af Soomaali) Spanish (español) Swahili (Kiswahili) Tagalog ( ... Disease Control and Prevention Return to top Portuguese (português) Carbon Monoxide Poisoning English Envenenamento por monóxido de ...

85

Summary Report of Several Ambient Carbon Monoxide Studies.  

National Technical Information Service (NTIS)

The Federal Clean Air Act assigns to the United States Environmental Protection Agency (EPA) the responsibility to promulgate National Ambient Air Quality Standards (NAAQS) regarding carbon monoxide (CO). On August 8, 1980 EPA proposed CO standards of 25 ...

M. Wolcott

1980-01-01

86

The Effect of Carbon Monoxide on Human Performance.  

National Technical Information Service (NTIS)

Carbon monoxide (CO) has become an important byproduct of increasing industrialization. The potential risk of this toxic substance applies not only to the general population, but also to specific subpopulations. This risk is considered extremely important...

P. J. Mikulka R. D. O'Donnell P. E. Heinig J. Theodore

1969-01-01

87

40 CFR 52.349 - Control strategy: Carbon monoxide.  

Code of Federal Regulations, 2010 CFR

...determined that the Denver carbon monoxide...national ambient air quality standard by...Maintenance Plan for Denver, as adopted by the Colorado Air Quality Control Commission...Maintenance Plan for Denver, as adopted by the Colorado Air Quality Control...

2009-07-01

88

40 CFR 52.349 - Control strategy: Carbon monoxide.  

Code of Federal Regulations, 2010 CFR

...determined that the Denver carbon monoxide...national ambient air quality standard by...Maintenance Plan for Denver, as adopted by the Colorado Air Quality Control Commission...Maintenance Plan for Denver, as adopted by the Colorado Air Quality Control...

2010-07-01

89

Measuring Carbon Monoxide in Auto Exhaust by Gas Chromatography.  

ERIC Educational Resources Information Center

Presents a simple and reliable technique using commonly available equipment for monitoring carbon monoxide in automobile exhaust. The experiment utilizes a gas chromatograph and a thermal conductivity detector (TCD). (DDR)

Jaffe, Dan; Herndon, Scott

1995-01-01

90

Atmospheric analyzer, carbon monoxide monitor and toluene diisocyanate monitor  

NASA Technical Reports Server (NTRS)

The purpose of the atmospheric analyzer and the carbon monoxide and toluene diisocyanate monitors is to analyze the atmospheric volatiles and to monitor carbon monoxide and toluene diisocyanate levels in the cabin atmosphere of Skylab. The carbon monoxide monitor was used on Skylab 2, 3, and 4 to detect any carbon monoxide levels above 25 ppm. Air samples were taken once each week. The toluene diisocyanate monitor was used only on Skylab 2. The loss of a micrometeoroid shield following the launch of Skylab 1 resulted in overheating of the interior walls of the Orbital Workshop. A potential hazard existed from outgassing of an isocyanate derivative resulting from heat-decomposition of the rigid polyurethane wall insulation. The toluene diisocyanate monitor was used to detect any polymer decomposition. The atmospheric analyzer was used on Skylab 4 because of a suspected leak in the Skylab cabin. An air sample was taken at the beginning, middle, and the end of the mission.

Shannon, A. V.

1977-01-01

91

Carbon monoxide poisoning in the United Arab Emirates.  

PubMed

Carbon monoxide (CO) poisoning is rare in the Arabian Peninsula and occurs almost exclusively during the winter months. Knowledge and perception of the hazards of carbon monoxide is limited. Migrant workers from warm climates appear particularly at risk. We investigated 46 cases of carbon monoxide poisoning presenting at emergency departments from 2007-2009 of the two main hospitals in Al Ain city, United Arab Emirates. Interviews, hospital records, and administered questionnaires were used to collect the data. Among the 46 cases investigated, 24 (52%) were males. Foreign nationals compromised 80% of the cases and the incidence was 3.1 cases per 100,000 residents per year. Burning charcoal in poorly ventilated residences was the predominant source of the carbon monoxide poisoning. Almost all cases (98%) were admitted during the winter months, most in the early morning hours. Carboxyhaemoglobin (COHb) was significantly increased in cases with loss of consciousness and depressed consciousness. There were no reported fatalities. PMID:21905387

Al Kaabi, Juma M; Wheatley, Andrew D; Barss, Peter; Al Shamsi, Mariam; Lababidi, Anis; Mushtaq, Ahmed

2011-01-01

92

Mechanism of Oxidative Stress from Low Levels of Carbon Monoxide.  

National Technical Information Service (NTIS)

The purpose of this study was to determine whether platelets and vascular endothelial cells liberate nitric oxide (NO) and NO-derived oxidant species after exposure to carbon monoxide (CO). We hypothesized that exposure to environmentally relevant concent...

S. R. Thom H. Ischiropoulos

1997-01-01

93

Carbon Monoxide Poisoning: Death on Mount McKinley,  

National Technical Information Service (NTIS)

Carbon monoxide (CO) poisoning is a common problem encountered in a wide variety of settings, including both suicide attempts and accidental exposures. Fatal CO exposure occurred in two wound, healthy mountain climbers who succumbed to fumes generated by ...

R. G. Foutch

1987-01-01

94

EVALUATION OF CONTINUOUS MONITORS FOR CARBON MONOXIDE IN STATIONARY SOURCES  

EPA Science Inventory

The performance characteristics of five commercially available continuous carbon monoxide monitors were evaluated in a two part program consisting of laboratory and field phases. The laboratory phase involved testing each instrument for response characteristics, precision, noise,...

95

Effects of Inspiratory Oxygen Concentration on Endtidal Carbon Monoxide Concentration  

Microsoft Academic Search

Objective. Carbon monoxide (CO) is eliminated mainly via the lungs so that exhaled carbon monoxide concentration reflects endogenous\\u000a production. In this context, we studied the effects of inspiratory oxygen concentration and endotracheal intubation on endtidal\\u000a CO concentrations. Methods. In patients undergoing general anaesthesia, endtidal CO concentrations were measured while breathing room air, oxygen as\\u000a well as after induction of general

Patrick Schober; Melanie Kalmanowicz; Stephan A. Loer

2006-01-01

96

Carbon Monoxide: An Essential Signalling Molecule  

NASA Astrophysics Data System (ADS)

Carbon monoxide (CO), like nitric oxide (NO), is an essential signalling molecule in humans. It is active in the cardiovascular system as a vasodilator. In addition, CO possesses anti-inflammatory, anti-apoptotic and anti-proliferative properties and protects tissues from hypoxia and reperfusion injury. Some of its applications in animal models include suppression of organ graft rejection and safeguarding the heart during reperfusion after cardiopulmonary bypass surgery. CO also suppresses arteriosclerotic lesions following angioplasty, reverses established pulmonary hypertension and mitigates the development of post-operative ileus in the murine small intestine and the development of cerebral malaria in mice as well as graft-induced intimal hyperplasia in pigs. There have been several clinical trials using air-CO mixtures for the treatment of lung-, heart-, kidney- and abdominal-related diseases. This review examines the research involving the development of classes of compounds (with particular emphasis on metal carbonyls) that release CO, which could be used in clinically relevant conditions. The review is drawn not only from published papers in the chemical literature but also from the extensive biological literature and patents on CO-releasing molecules (CO-RMs).

Mann, Brian E.

97

Where to now with carbon monoxide poisoning?  

PubMed

The controversy regarding the role of hyperbaric oxygen (HBO) in the treatment of carbon monoxide (CO) poisoning has been re-ignited following the publication of a further randomized controlled trial by Weaver et al., the results of which appear to conflict with our findings. Comparative analysis suggests that the apparent outcome differences may be secondary to the design, analysis and interpretation of the results of the two studies. Following careful analysis of these two papers and further results from a study by Raphael et al on 385 CO-poisoned patients, we can still find no convincing evidence favouring HBO therapy. Pending further research to determine optimal oxygen therapy for CO-poisoning, current therapy should involve stratifying patients for risk of a poor outcome. This stratification may be aided by the evolving availability of biochemical markers of brain injury and the finding that patients with transient loss of consciousness and poor performance on neuropsychological tests of the supervisory attention system are at higher risk of neuropsychological sequelae. We propose that those patients most at risk be admitted and receive more prolonged normobaric oxygen therapy whilst those with more minor CO-poisoning should be provided with normobaric oxygen of no less than 6 h duration and certainly until sign and symptom free. PMID:15239731

Scheinkestel, Carlos D; Jones, Kerry; Myles, Paul S; Cooper, D Jamie; Millar, Ian L; Tuxen, David V

2004-04-01

98

Carbon monoxide measurements at Mace Head, Ireland  

NASA Technical Reports Server (NTRS)

The North Atlantic Ocean is bordered by continents which may each, under the influence of seasonal weather patterns, act as sources of natural and anthropogenic trace gas and particulate species. Photochemically active species such as carbon monoxide (CO) react to form ozone (O3), a species of critical importance in global climate change. CO is sparingly soluble in water, and the relatively long lifetime of CO in the troposphere makes this species an ideal tracer of air masses with origin over land. We have measured CO using a nondispersive infrared gas filter correlation analyzer at Mace Head on the west coast of Ireland nearly continuously since August 9, 1991. Measurements of CO were acquired at 20-sec resolution and recorded as 60-sec averages. Daily, monthly, and diurnal variation data characteristics of CO mixing ratios observed at this site are reported. Depending on source regions of air parcels passing over this site, 60-min concentrations of CO range from clean air values of approximately 90 ppbv to values in excess of 300 ppbv. Data characterizing the correlation between 60-min CO and O3 mixing ratio data observed at this site are reported also.

Doddridge, Bruce G.; Dickerson, Russell R.; Spain, T. Gerard; Oltmans, Samuel J.; Novelli, Paul C.

1994-01-01

99

Review: hemodynamic response to carbon monoxide  

SciTech Connect

Historically, and at present, carbon monoxide is a major gaseous poison responsible for widespread morbidity and mortality. From threshold to maximal nonlethal levels, a variety of cardiovascular changes occur, both immediately and in the long term, whose homeostatic function it is to renormalize tissue oxygen delivery. However, notwithstanding numerous studies over the past century, the literature remains equivocal regarding the hemodynamic responses in animals and humans, although CO hypoxia is clearly different in several respects from hypoxic hypoxia. Factors complicating interpretation of experimental findings include species, CO dose level and rate, route of CO delivery, duration, level of exertion, state of consciousness, and anesthetic agent used. Augmented cardiac output usually observed with moderate COHb may be compromised in more sever poisoning for the same reasons, such that regional or global ischemia result. The hypotension usually seen in most animal studies is thought to be a primary cause of CNS damage resulting from acute CO poisoning, yet the exact mechanism(s) remains unproven in both animals and humans, as does the way in which CO produces hypotension. This review briefly summarizes the literature relevant to the short- and long-term hemodynamic responses reported in animals and humans. It concludes by presenting an overview using data from a single species in which the most complete work has been done to date.

Penney, D.G.

1988-04-01

100

Decadal record of satellite carbon monoxide observations  

NASA Astrophysics Data System (ADS)

Atmospheric carbon monoxide (CO) distributions are controlled by anthropogenic emissions, biomass burning, transport and oxidation by reaction with the hydroxyl radical (OH). Quantifying trends in CO is therefore important for understanding changes related to all of these contributions. Here we present a comprehensive record of satellite observations from 2000 through 2011 of total column CO using the available measurements from nadir-viewing thermal infrared instruments: MOPITT, AIRS, TES and IASI. We examine trends for CO in the Northern and Southern Hemispheres along with regional trends for Eastern China, Eastern USA, Europe and India. We find that all the satellite observations are consistent with a modest decreasing trend ~ -1 % yr-1 in total column CO over the Northern Hemisphere for this time period and a less significant, but still decreasing trend in the Southern Hemisphere. Although decreasing trends in the United States and Europe have been observed from surface CO measurements, we also find a decrease in CO over E. China that, to our knowledge, has not been reported previously. Some of the interannual variability in the observations can be explained by global fire emissions, but the overall decrease needs further study to understand the implications for changes in anthropogenic emissions.

Worden, H. M.; Deeter, M. N.; Frankenberg, C.; George, M.; Nichitiu, F.; Worden, J.; Aben, I.; Bowman, K. W.; Clerbaux, C.; Coheur, P. F.; de Laat, A. T. J.; Detweiler, R.; Drummond, J. R.; Edwards, D. P.; Gille, J. C.; Hurtmans, D.; Luo, M.; Martínez-Alonso, S.; Massie, S.; Pfister, G.; Warner, J. X.

2013-01-01

101

Carbon Monoxide Formation in SN 1987A  

NASA Technical Reports Server (NTRS)

The formation of carbon monoxide in the supernova SN 1987A at 200 days is investigated. Rather than the one-zone that have previous been employed, this work utilizes a radially dependent radiative transport model to compute the temperature and ionization structure and the destruction of CO and CO+ by ultraviolet radiation. The CO profile is computed assuming chemical equilibrium. Two models for the density and abundance profiles are examined: model 10H (unmixed) and model 10HMM (mixed) of Pinto & Woosley. Sensitivity to adopted rates and temperature as it might be affected by CO cooling is examined. The models give a total mass of 10-4 M_sun at 200 days for the unmixed model, which is comparable with the estimated observed abundance by Syromilio et al. but nearly 2 orders of magnitude less than the estimated observed and that computed in thermal-chemical models by Liu & Dalgarno. The effect of different model assumptions and results concerning ionization structure and radiative transfer are discussed. We confirm that CO+ is not expected to be produced in significant amounts and that the amount of CO is sensitive to the degree of the mixing of the composition of various elements present in the ejecta.

Gearhart, Rob A.

1999-01-01

102

Effect of carbon monoxide on the cardiorespiratory system: carbon monoxide toxicity, physiology and biochemistry  

SciTech Connect

Exposure to carbon monoxide compromises function of the cardiovascular system primarily by decreasing oxygen-carrying capacity in the blood and decreasing venous and tissue oxygen tension. In normal individuals, with concentrations of approximately 18 to 20% COHb, there is a reduction in the oxygen consumption during high levels of exercise, a higher than predicted cardiac output, and abnormally high concentrations of lactic acid. However, in patients with coronary artery atherosclerosis, concentrations of COHb of 3 to 5% significantly curtailed exercise tolerance before the onset of angina. In addition, there is suggestive evidence in animals that the hypoxia induced by increased levels of COHb induces atherosclerosis.

Turino, G.M.

1981-01-01

103

Demonstration of Oxygen and Carbon Monoxide Propellants for Mars Missions  

NASA Technical Reports Server (NTRS)

Currently, proposed planetary exploration missions must be small, with low costs and a short development time. Relatively high-risk technologies are being accepted for such missions if they meet these guidelines. For a Mars sample-return mission, one of the higher risk technologies is the use of return propellants produced from indigenous materials such as the Martian atmosphere. This consists of 96 percent carbon dioxide, which can be processed into oxygen and carbon monoxide. This year, the NASA Lewis Research Center completed the experimental evaluation and subscale technology development of an oxygen/carbon monoxide propellant combination. Previous research included ignition characterization, combustion performance, and heat transfer characterization with gaseous propellants at room temperature. In this year s tests, we studied the ignition characteristics and combustion of oxygen and carbon monoxide at near liquid temperatures. The mixture ratio boundaries for oxygen and carbon monoxide were determined as a function of propellant temperature in a spark torch igniter. With both propellants at room temperature, the ignition range was between 0.50 and 1.44; and with both propellants chilled to near-liquid temperatures, it was between 2.4 and 3.1. Statistical analysis of the mean value of the ignition boundaries provided models that describe the combination of oxygen temperature, carbon monoxide temperature, and mixture ratio that resulted in ignition. This range is the larger boxed area shown in the figure. The smaller boxed area indicates the range at which there is a 90-percent confidence that ignition will occur. The relatively small range at only 90-percent confidence indicates that using the oxygen/carbon monoxide combination as its own ignition source may not be the best design for a remote engine operating on Mars. Tests also were performed in a simulated small rocket engine that used oxygen/hydrogen combustion gases as the ignition source for oxygen/carbon monoxide. In these experiments, the oxygen/carbon monoxide was successfully ignited in eight of eight tests at a mixture ratio of 0.52. In addition, the oxygen/carbon monoxide maintained steady combustion after the oxygen/hydrogen ignition source was removed, verifying that the oxygen/carbon monoxide rocket engine should continue to be included in mission plans as return propulsion from Mars.

Linne, Diane L.

1997-01-01

104

Mathematical models of the uptake of carbon monoxide on hemoglobin at low carbon monoxide levels.  

PubMed Central

Coburn's differential equation for the uptake of carbon monoxide by hemoglobin and two particular types of solution of this equation were considered and the solutions verified for a group of healthy adults consisting of 73 nonsmoking pedestrians or car passengers exposed to low levels of carbon monoxide as experienced in the city of Lyon. The CO levels at the breathing level and the walking speed of the subjects was continually measured, and the carboxyhemoglobin levels determined at the beginning and the end of each test journey. The values of all the other relevant parameters were also determined. The half-life of carboxyhemoglobin was studied as a function of the degree of activity, the age, the sex and the height of the subjects. Finally a mathematical model was set up to represent a periodic uptake of CO which made it possible to estimate the variations in the carboxyhemoglobin level for any subject during a period of a day or a week without any need to know the initial level.

Joumard, R; Chiron, M; Vidon, R; Maurin, M; Rouzioux, J M

1981-01-01

105

Decadal Record of Satellite Carbon Monoxide Observations  

NASA Astrophysics Data System (ADS)

Atmospheric carbon monoxide (CO) distributions are controlled by anthropogenic emissions, biomass burning, chemical production, transport and oxidation by reaction with the hydroxyl radical (OH). Quantifying trends in CO is therefore important for understanding changes related to all of these contributions. Here we present a comprehensive record of satellite observations from 2000 through 2011 of total column CO using the available measurements from nadir-viewing thermal infrared instruments: MOPITT, AIRS, TES and IASI. We examine trends for CO in the Northern and Southern hemispheres along with regional trends for E. China, E. USA, Europe and India. Measurement and sampling methods for each of the instruments are discussed, and we show diagnostics for systematic errors in MOPITT trends. We find that all the satellite observations are consistent with a modest decreasing trend around -1%/year in total column CO over the Northern hemisphere for this time period. Decreasing trends in total CO column are observed for the United States, Europe and E. China with more than 2? significance. For India, the trend is also decreasing, but smaller in magnitude and less significant. Decreasing trends in surface CO have also been observed from measurements in the U.S. and Europe. Although less information is available for surface CO in China, there is a decreasing trend reported for Beijing. Some of the interannual variability in the observations can be explained by global fire emissions, and there may be some evidence of the global financial crisis in late 2008 to early 2009. But the overall decrease needs further study to understand the implications for changes in anthropogenic emissions.

Worden, Helen; Deeter, Merritt; Frankenberg, Christian; George, Maya; Nichitiu, Florian; Worden, John; Aben, Ilse; Bowman, Kevin; Clerbaux, Cathy; Coheur, Pierre-Francois; de Laat, Jos; Warner, Juying; Drummond, James; Edwards, David; Gille, John; Hurtmans, Daniel; Ming, Luo; Martinez-Alonso, Sara; Massie, Steven; Pfister, Gabriele

2013-04-01

106

Material Processing with Hydrogen and Carbon Monoxide on MARS.  

National Technical Information Service (NTIS)

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydr...

A. F. Hepp G. A. Landis D. L. Linne

1991-01-01

107

Material processing with hydrogen and carbon monoxide on Mars  

Microsoft Academic Search

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol,

Aloysius F. Hepp; Geoffrey A. Landis; Diane L. Linne

1991-01-01

108

The oxidation of carbon monoxide using tin oxide based catalysts  

NASA Technical Reports Server (NTRS)

The preparation conditions for precious metal/tin oxide catalysts were optimized for maximum carbon monoxide/oxygen recombination efficiency. This was achieved by controlling the tin digestion, the peptization to form the sol, the calcination process and the method of adding the precious metals. Extensive studies of the tin oxide structure were carried out over the temperature range 20 to 500 C in air or hydrogen environments using Raman scattering and X ray diffraction. Adsorbed species on tin oxide, generated in an environment containing carbon monoxide, gave rise to a Raman band at about 1600 cm(exp -1) which was assigned to carbonaceous groups, possible carbonate.

Sampson, Christopher F.; Jorgensen, Norman

1990-01-01

109

Acute effects of carbon monoxide on cardiac electrical stability  

SciTech Connect

The objective of this project was to determine the effects of acute carbon monoxide exposure on cardiac electrical stability. To obtain a comprehensive assessment, diverse biological models were employed. These involved cardiac electrical testing in the normal and ischemic heart in anesthetized and conscious dogs. The experimental plan was designed both to examine the direct effects of carbon monoxide exposure on the myocardium and to evaluate possible indirect influences through alterations in platelet aggregability or changes in central nervous system activity in the conscious animal. Our results indicate that exposure to relatively high levels of carbon monoxide, leading to carboxyhemoglobin concentrations of up to 20 percent, is without significant effect on ventricular electrical stability. This appears to be the case in the acutely ischemic heart as well as in the normal heart. It is important to note that the total exposure period was in the range of 90 to 124 minutes. The possibility that longer periods of exposure or exacerbation from nicotine in cigarette smoke could have a deleterious effect cannot be excluded. We also examined whether or not alterations in platelet aggregability due to carbon monoxide exposure could be a predisposing factor for cardiac arrhythmias. A model involving partial coronary artery stenosis was used to simulate the conditions under which platelet plugs could lead to myocardial ischemia and life-threatening arrhythmias. We found no changes either in the cycle frequency of coronary blood flow oscillations or in platelet aggregability during carbon monoxide exposure. Thus, carbon monoxide exposure does not appear to alter platelet aggregability or its effect on coronary blood flow during stenosis. In the final series of experiments, we examined the effects of carbon monoxide exposure in the conscious state.

Verrier, R.L.; Mills, A.K.; Skornik, W.A. (Georgetown Univ. Medical Center, Washington, DC (USA))

1990-10-01

110

CRISM Observations of Water Vapor and Carbon Monoxide  

NASA Technical Reports Server (NTRS)

Near-infrared spectra returned by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM, [1]) on-board the Mars Reconnaissance Orbiter (MRO) contain the clear spectral signature of several atmospheric gases including carbon dioxide (CO2), water vapor (H2O), and carbon monoxide (CO). Here we describe the seasonal and spatial mapping of water vapor and carbon dioxide for one full Martian year using CRISM spectra.

Smith, Michael D.; Wolff, Michael J.; Clancy, R. Todd

2008-01-01

111

Effects of carbon monoxide on myocardial ischemia.  

PubMed Central

The purpose of this study was to determine whether low doses of carbon monoxide (CO) exacerbate myocardial ischemia during a progressive exercise test. The effect of CO exposure was evaluated using the objective measure of time to development of electrocardiographic changes indicative of ischemia and the subjective measure of time to onset of angina. Sixty-three male subjects (41-75 years) with well-documented coronary artery disease, who had exertional angina pectoris and ischemic ST-segment changes in their electrocardiograms, were studied. Results from three randomized, double-blind test visits (room air, low and high CO) were compared. The effect of CO exposure was determined from the percent difference in the end points obtained on exercise tests performed before and after a 1-hr exposure to room air or CO. The exposures resulted in postexercise carboxyhemoglobin (COHb) levels of 0.6% +/- 0.3%, 2.0% +/- 0.1%, and 3.9% +/- 0.1%. The results obtained on the 2%-COHb day and 3.9%-COHb day were compared to those on the room air day. There were 5.1% (p = 0.01) and 12.1% (p less than or equal to 0.0001) decreases in the time to development of ischemic ST-segment changes after exposures producing 2.0 and 3.9% COHb, respectively, compared to the control day. In addition, there were 4.2% (p = 0.027) and 7.1% (p = 0.002) decreases in time to the onset of angina after exposures producing 2.0 and 3.9% COHb, respectively, compared to the control day. A significant dose-response relationship was found for the individual differences in the time to ST end point and angina for the pre- versus postexposure exercise tests at the three carboxyhemoglobin levels. These findings demonstrate that low doses of CO produce significant effects on cardiac function during exercise in subjects with coronary artery disease.

Allred, E N; Bleecker, E R; Chaitman, B R; Dahms, T E; Gottlieb, S O; Hackney, J D; Pagano, M; Selvester, R H; Walden, S M; Warren, J

1991-01-01

112

MY NASA DATA: Carbon Monoxide and Population Density  

NSDL National Science Digital Library

This lesson is designed to help students gain knowledge in using the MY NASA DATA Live Access Server (LAS) to specify and download a microset of data, then use the data to investigate the carbon monoxide level at a fixed latitude. Using the LAS, students will download data, and will then use a spreadsheet program to create maps of the carbon monoxide level for a particular latitude. They will then look for trends and explore the population density for selected points along the latitude (urban or rural). The lesson provides detailed procedure, related links and sample graphs, follow-up questions and extensions, and Teacher Notes.

2006-04-10

113

Studies relevant to the catalytic activation of carbon monoxide  

SciTech Connect

Research activity during the current funding period (December 87 to present) of this grant has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key steps in the relevant catalytic cycles. In addition, new investigations of related processes involved in the catalytic activation of carbon monoxide and other C{sub 1} compounds were initiated. These include the application of fast reaction techniques to prepare and to investigate quantitatively reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and other functionalizations. 39 refs., 7 figs.

Ford, P.C.

1990-05-11

114

Control of hydrocarbons and carbon monoxide via catalytic incineration  

SciTech Connect

Eight commercially available incineration catalysts were evaluated experimentally to assess their application to control hydrocarbon and carbon monoxide emissions in the tail gases from a Lurgi substitute natural gas plant, which were simulated using bottled gas mixtures. Catalysts were evaluated with respect to the effects of temperature, space velocity, and the presence of hydrogen sulfide and carbonyl sulfide on hydrocarbon and carbon monoxide conversion. Results indicate that within the scope of this study the most effective catalysts are a precious-metal-based catalyst on a monolithic substrate and a nonprecious metal oxide deposited on a solid substrate formed into 3.2-mm-diam spheres.

Brown, C.H. Jr.; Klein, J.A.

1981-09-01

115

77 FR 31351 - Adequacy Determination for Aspen PM10 and Fort Collins Carbon Monoxide Maintenance Plans' Motor...  

Federal Register 2010, 2011, 2012, 2013

...for Aspen PM[bdi1][bdi0] and Fort Collins Carbon Monoxide Maintenance Plans' Motor...Carbon Monoxide Maintenance Plan Fort Collins Attainment/Maintenance Area.'' As...transconf/currsips.htm#aspen). Fort Collins (Carbon Monoxide): The State...

2012-05-25

116

The Relationship Between Ambient Carbon Monoxide Levels, Postmortem Carboxyhemoglobin, Sudden Death and Myocardial Infarction.  

National Technical Information Service (NTIS)

The relationship between carbon monoxide exposure and heart attacks was studied in Baltimore, Maryland. Four hypotheses were tested: (1) Is there a relationship between sudden death and myocardial infarction and ambient carbon monoxide levels. (2) Are pos...

L. H. Kuller E. P. Radford D. Swift J. A. Perper R. Fisher

1974-01-01

117

40 CFR 52.1164 - Localized high concentrations-carbon monoxide.  

Code of Federal Regulations, 2013 CFR

...Identify areas of potentially high carbon monoxide concentrations by...meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary...extent and actual levels of carbon monoxide in the area. A...

2013-07-01

118

Carbon monoxide: A quantitative tracer for fossil fuel CO2?  

Microsoft Academic Search

Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon (14CO2) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The observations were compared with model estimates simulated with the regional transport model REMO at

Ulrike Gamnitzer; Ute Karstens; Bernd Kromer; Rolf E. M. Neubert; Harro A. J. Meijer; Hartwig Schroeder; Ingeborg Levin

2006-01-01

119

Catalytic conversion of carbon monoxide from carbonaceous heat sources  

SciTech Connect

A method is described for producing a heat source, comprising the steps of: (a) mixing a carbon component, a catalytic precursor, and a binder, wherein the catalytic precursor is a metal species which upon combustion of the heat source forms a catalyst for converting carbon monoxide produced during combustion of the heat source to a benign substance; (b) forming the mixture into a shape; and (c) supplying heat to the mixture.

Deevi, S.C.; Hajaligol, M.R.; Kellogg, D.S.; Waymack, B.E.

1993-08-31

120

Release of Carbon Monoxide from Acrylic and Polycarbonate Plastics.  

National Technical Information Service (NTIS)

Transparent polycarbonate and acrylic plastics were exposed to air, nitrogen, and oxygen in glass containers at 25C. Carbon monoxide was released from both types of plastic into the gas phase. The amount of CO released from a given plastic sample was simi...

F. L. Rodkey H. A. Collison R. R. Engel

1969-01-01

121

Comparisons of Carbon Monoxide Measurements using Aircraft and Model Data  

Microsoft Academic Search

Carbon Monoxide (CO) is an important trace gas species in the atmosphere and is chiefly produced from biomass burning and transportation emission. CO is one of the few tropospheric gases that can be monitored and simulated successfully using aircraft, satellite and Chemical Transported Models (CTM). In this present study, comparisons of CO observations are made between aircraft and model run

Partha Sarathi Bhattacharjee; Joanna Joiner

122

Integrated Science Assessment for Carbon Monoxide (Second External Review Draft)  

EPA Science Inventory

EPA has announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes have been made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evalu...

123

Integrated Science Assessment for Carbon Monoxide (First External Review Draft)  

EPA Science Inventory

EPA has announced that the First External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes have been made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evalua...

124

Hydrocarbon and carbon monoxide emissions from biomass burning in Brazil  

Microsoft Academic Search

Field measurements of hydrocarbon emissions from biomass burning in the cerrado (grasslands) and selva (tropical forest) regions of Brazil in 1979 and 1980 are characterized and quantified here. Regional consequences of burning activities include increased background mixing ratios of carbon monoxide and ozone, as well as reduced visibility, over extensive areas. Global extrapolation of the emission rate of hydrocarbons from

J. P. Greenberg; P. R. Zimmerman; L. Heidt; W. Pollock

1984-01-01

125

Carbon monoxide detector. [electrochemical gas detector for spacecraft use  

NASA Technical Reports Server (NTRS)

A sensitive carbon monoxide detector, developed specifically for spacecraft use, is described. An instrument range of 0 to 60 ppm CO in air was devised. The fuel cell type detector is used as a highly sensitive electrolysis cell for electrochemically detecting gases. The concept of an electrochemical CO detector is discussed and the CO oxidation behavior in phosphoric and sulfuric acid electrolytes is reported.

Holleck, G. L.; Bradspies, J. L.; Brummer, S. B.; Nelsen, L. L.

1973-01-01

126

21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.  

Code of Federal Regulations, 2013 CFR

...than 30 weight-percent of polymer units derived from carbon monoxide...Conditions of use. (1) The polymers may be safely used as components...food-contact articles. (2) The polymers may be safely used as food-contact...condition E âStandard Test Method for Flow...

2013-04-01

127

Carbon monoxide poisoning: easy to treat but difficult to recognise  

Microsoft Academic Search

Carbon monoxide (CO) poisoning is a common medical emergency and a frequent cause of deliberate or accidental death. It can cause acute and chronic central nervous system damage which may be minimised by prompt treatment with 100% oxygen or hyperbaric oxygen therapy. However, recognition of this intoxication can be difficult. Failure to diagnose it may have disastrous effects on the

M. V. Balzan; G. Agius; A. Galea Debono

1996-01-01

128

CARBOXYHEMOGLOBIN FORMATION DUE TO CARBON MONOXIDE IN RATS  

EPA Science Inventory

The Coburn-Forster-Kane equation (CFKE) ia a well tested model for prediction of COHb formation due to carbon monoxide (CO) exposure in humans. here have been few and relatively poorly tested attempts to implement a CFKE for rats. uch an implementation is of interest because many...

129

Prenatal exposure to carbon monoxide delays postnatal cardiac maturation  

Microsoft Academic Search

Prenatal exposure to toxicants, such as maternal smoking, may impair cardiovascular autonomic maturation in infants. We recently showed that exposure of pregnant rats to a mild concentration of carbon monoxide (CO), a component of cigarette smoke, delays postnatal electrophysiological maturation of ventricular myocytes from newborns rats, likely predisposing to life-threatening arrhythmias. To get a comprehensive view of developmental molecular abnormalities

Laura Sartiani; Francesca Stillitano; Cristina Luceri; Silvia Suffredini; Simona Toti; Carlotta De Filippo; Vincenzo Cuomo; Maria Tattoli; Piero Dolara; Alessandro Mugelli; Elisabetta Cerbai

2010-01-01

130

Carbon Monoxide-Sensitized Decomposition of Hydrogen Peroxide.  

National Technical Information Service (NTIS)

Carbon monoxide accelerates the decomposition of H2O2 because the propagation reaction (1) competes with the termination reaction (2): (1) OH + CO = CO2 + H; (2) OH + H2O2 = H2O + HO2. The accelerating effect of high concentrations of CO requires the intr...

R. R. Baldwin R. W. Walker S. J. Webster

1970-01-01

131

Tita: discovery of carbon monoxide in its atmosphere  

NASA Technical Reports Server (NTRS)

The 3-D rotation-vibration band of carbon monoxide was identified in the near-infrared spectrum of Titan. A preliminary mixing ratio of CO/N2 = 0.00006 was determined. This result supports the probable detection of CO2 by Samuelson et al and strengthens possible analogies between the atmosphere of Titan and conditions on the primitive Earth.

Lutz, B. L.; Debergh, C.; Owen, T.

1982-01-01

132

Carbon monoxide poisoning of proton exchange membrane fuel cells  

Microsoft Academic Search

SUMMARY Proton exchange membrane fuel cell (PEMFC) performance degrades when carbon monoxide (CO) is present in the fuel gas; this is referred to as CO poisoning. This paper investigates CO poisoning of PEMFCs by reviewing work on the electrochemistry of CO and hydrogen, the experimental performance of PEMFCs exhibiting CO poisoning, methods to mitigate CO poisoning and theoretical models of

J. J. Baschuk; Xianguo Li

2001-01-01

133

Neural network application in a carbon monoxide measurement system  

Microsoft Academic Search

Reports an application of neural networks to the measurement of carbon monoxide in air. The measurement system uses a tin film sensor. To increase system performances and capabilities, a microcontroller and complex processing are added to the sensor. Several artificial neural network architectures are designed, tested and implemented in the microcontroller to perform the CO digital readout task with compensation

Octavian POSTOLACHE; P. Girao; Miguel PEREIRA

2001-01-01

134

The combined effect of noise and carbon monoxide on hearing thresholds of exposed workers  

Microsoft Academic Search

Animal models have been used to demonstrate the potentiation of noise-induced hearing loss (NIHL) by carbon monoxide. It has been shown that the addition of carbon monoxide to otherwise safe noise exposure levels produces significant NIHL in rats. However, the effects of chronic exposure to low level of carbon monoxide in a noisy work environment are still unknown. The aim

Adriana Lacerda; Tony Leroux; Jean-Pierre Gagn

2005-01-01

135

Studies relevant to the catalytic activation of carbon monoxide  

SciTech Connect

Research activity during the 1991--1992 funding period has been concerned with the following topics relevant to carbon monoxide activation. (1) Exploratory studies of water gas shift catalysts heterogenized on polystyrene based polymers. (2) Mechanistic investigation of the nucleophilic activation of CO in metal carbonyl clusters. (3) Application of fast reaction techniques to prepare and to investigate reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and to the formation of carbon-carbon bonds via the migratory insertion of CO into metal alkyl bonds.

Ford, P.C.

1992-06-04

136

Rationalizing Burned Carbon with Carbon Monoxide Exported from South America  

NASA Technical Reports Server (NTRS)

We present several estimates cross-checking the fluxes of carbon to the atmosphere from burning, comparing models that are based on simple land-surface parameterizations and atmospheric transport dynamics. Both estimates made by NASA Ames and USP modeling techniques are quite high compared to some detailed satellite/land-use studies of emissions. The flux of carbon liberated to the atmosphere via biomass burning is important for several reasons. This flux is a fundamental statistic for the parameterization of the large-scale flux of gases controlling the reactive greenhouse gases methane and ozone. Similarly, it is central to the estimation of the translocation of nitrogen and pyrodenitrification in the tropics. Thirdly, CO2 emitted from rainforest clearing contributes directly to carbon lost from the rainforest system as it contributes to greenhouse gas forcing. While CO2 from pasturage, agriculture, etc, is considered to be reabsorbed seasonally, and so "off budget" for the carbon cycle, it must also be accounted. CO2 anomalies related to daily weather and interannual climatic variation are strong enough to perturb our scientific perception of long-term carbon storage trends. We compare fluxes deduced from land-use statistics (originally, W.M. Hao) and from satellite hot pixels (A. Setzer) with atmospheric fluxes determined by the mesoscale/continental scale models RAMS and MM5, and point to some new work with highly resolved global models (the NASA Data Assimilation Office's GEOS4). Our simulations are tied to events, so that measured tracers like CO tie the models directly to the burning and meteorology of a specific period. We point out a particular sensitivity in estimates based on CO, and indicate how analysis of CO2 along with other biomass-burning tracers may lead to an improved multi-species estimator of carbon burned.

Chatfield, R.; Freitas, S. R.; SilvaDias, M. A.; SilvaDias, P. O.; Hipskind, R. Stephen (Technical Monitor)

2002-01-01

137

Carbon monoxide metabolism by the photosynthetic bacterium Rhodospirillum rubrum  

SciTech Connect

Research continued on carbon monoxide metabolism by Rhodospirillum rubrum. In the past year, progress was made in: (1) the identification and isolation of the physiological electron carrier from monoxide dehydrogenase (CODH) to hydrogenase in R. rubrum; (2) the isolation, sequencing and mutagenesis of the genes encoding the components of the CO oxidation system in R. rubrum, (3) the purification and characterization of the CO-induced hydrogenase activity of R. rubrum; (4) the spectroscopic investigation of the cobalt-substituted form of the enzyme.

Ludden, P.W.; Roberts, G.P.

1991-01-01

138

Carbon monoxide poisoning during natural disasters: the Hurricane Rita experience.  

PubMed

We report the incidence and mechanisms of carbon monoxide exposure during the first 5 days after Hurricane Rita, as experienced by a Disaster Medical Assistance Team staffing the only open health care facility in the Beaumont, Texas region after the storm. Improper placement of portable generators in indoor locations or proximate to home air conditioning intake systems were completely responsible for the 21 exposures including 5 fatalities, 1 brain dead, 2 transfers for hospitalization, and 13 treated and released. We discuss the clinical presentations and treatment approaches, provide a brief overview of carbon monoxide and offer novel preventive recommendations. Portable generator use after disasters represents a predictable risk to the public. Proper ventilation requirements for generators are not adequately appreciated and engineered safeties should be explored to mitigate illness. PMID:17976553

Cukor, Jeffrey; Restuccia, Marc

2007-10-01

139

Diffusing capacity and anatomic dead space for carbon-18 monoxide.  

NASA Technical Reports Server (NTRS)

Carbon monoxide (CO) is difficult to measure with a respiratory mass spectrometer because of the similar mass numbers of CO and nitrogen, but this is possible using carbon-18 monoxide. The mass resolution, signal-to-noise ratio, linearity, and background were all found to be adequate. The measurement of the single-breath diffusing capacity was examined. Unless the mean alveolar volume during breath holding is used in the calculation, the value for Dco obtained depends on which portion of the alveolar sample is analyzed. The anatomic dead space for CO was found to be almost the same as that for argon suggesting that the diffusion rate at the dead space-alveolar gas interface was not greatly affected by the alveolar concentration of the gas.

Wagner, P. D.; Mazzone, R. W.; West, J. B.

1971-01-01

140

Composite catalyst for carbon monoxide and hydrocarbon oxidation  

DOEpatents

A method and composition for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdnum, copper, cobalt, maganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

Liu, Wei (Cambridge, MA); Flytzani-Stephanopoulos, Maria (Winchester, MA)

1996-01-01

141

Interactions of carbon monoxide and hemoglobin at high altitude  

NASA Astrophysics Data System (ADS)

The health risks to U.S. populations who are exposed to ambient carbon monoxide and live at altitudes (such as Denver, Salt Lake City and Albuquerque) were evaluated using a set of mathematical models. The assumption that a given increase in carboxyhemoglobin would require a more stringent volumetric air quality standard was tested. The results using the model predict that the 8-h or 1-h standards adopted for sea level conditions need not be altered to protect individuals against health risks at altitude, if the standards are in volumetric terms. They would need to be reduced if the standards are left in gravimetric terms. If the guideline is to be based on a given decrement of oxygen tension, many other variables must be specified, but expected differences in ambient carbon monoxide have a small impact compared to the effect of altitude itself.

Collier, Clarence R.; Goldsmith, John R.

142

Effect of carbon monoxide and nitrogen dioxide on ICR mice  

NASA Technical Reports Server (NTRS)

Times to incapacitation and death and LC(50) values were determined for male ICR mice exposed to different concentration of carbon monoxide for 30 min and of nitrogen dioxide for 10 min in a 4.2 liter hemispherical chamber. The data indicate that ICR mice are more resistant to these two toxicants than Swiss albino mice. The carbon monoxide LC(50) for a 30-min exposure was about 8,000 ppm for ICR mice compared to 3,570 ppm for Swiss albino mice. The nitrogen dioxide LC(50) for a 10-min exposure was above 2,000 ppm for ICR mice compared to about 1,000 ppm for Swiss albino mice.

Hilado, C. J.; Cumming, H. J.

1977-01-01

143

Carbon monoxide and methane over Canada: July-August 1990  

SciTech Connect

This article describes the results of a 1990 study of the concentrations of tropospheric methane and carbon monoxide in the troposphere above central and eastern Canada. Gas concentrations were measured in the 0.15 to 6 kilometer range of the troposphere using a tunable diode laser instrument. Variable concentrations of both methane and carbon monoxide were documented at altitudes of 0.15 to 6 kilometers over relatively pristine areas. The variability of gas concentration is explained by meteorological factors and local emission sources. The sources are thought to include uncontrolled wildfires, American industrial and urban emissions, retreat of the polar fronts, and emissions from wetland sources. 22 refs., 11 figs., 1 tab.

Harriss, R.C.; Bartlett, K.B.; Talbot, R.W. [Univ. of New Hampshire, Durham, NH (United States)] [Univ. of New Hampshire, Durham, NH (United States); Sachse, G.W.; Collins, J.E. Jr.; Browell, E.V.; Hill, G.F. [NASA Langley Research Center, Hampton, VA (United States)] [NASA Langley Research Center, Hampton, VA (United States); Wade, L. [Lockheed Engineering and Science, Hampton, VA (United States)] [Lockheed Engineering and Science, Hampton, VA (United States); Barrie, L.A. [Atmospheric Environment Service, Ontario (Canada)] [Atmospheric Environment Service, Ontario (Canada); Burney, L.G. [STC Corp., Hampton, VA (United States)] [STC Corp., Hampton, VA (United States)

1994-01-20

144

Catalyst for the methanation of carbon monoxide in sour gas  

DOEpatents

The invention involves the synergistic effect of the specific catalytic constituents on a specific series of carriers for the methanation of carbon monoxide in the presence of sulfur at relatively high temperatures and at low steam to gas ratios in the range of 0.2:1 or less. This effect was obtained with catalysts comprising the mixed sulfides and oxides of nickel and chromium supported on carriers comprising magnesium aluminate and magnesium silicate. Conversion of carbon monoxide to methane was in the range of from 40 to 80%. Tests of this combination of metal oxides and sulfides on other carriers and tests of other metal oxides and sulfides on the same carrier produced a much lower level of conversion.

Kustes, William A. (Louisville, KY); Hausberger, Arthur L. (Louisville, KY)

1985-01-01

145

Catalysis of carbon monoxide methanation by deep sea manganate minerals.  

PubMed

The catalytic activity of deep sea manganese nodule minerals for the methanation of carbon monoxide was measured with a microcatalytic technique between 200 and 460 degrees C. The manganate minerals were activated at 248 degrees C by immersion into a stream of hydrogen in which pulses of carbon monoxide were injected. Activation energies for the methanation reaction and hydrogen desorption from the manganate minerals were obtained and compared with those of pure nickel. Similar energy values indicate that the activity of the nodule materials for the reaction appears to be related to the amount of reducible transition metals present in the samples (ca. 11 wt.-%). Since the activity of the nodule minerals per gram is comparable to that of pure nickel, most of the transition metal ions located between manganese oxide layers appear to be exposed and available to catalyze the reaction. PMID:11538653

Cabrera, A L; Maple, M B; Arrhenius, G

1990-01-01

146

Catalysis of carbon monoxide methanation by deep sea manganate minerals  

NASA Technical Reports Server (NTRS)

The catalytic activity of deep sea manganese nodule minerals for the methanation of carbon monoxide was measured with a microcatalytic technique between 200 and 460 degrees C. The manganate minerals were activated at 248 degrees C by immersion into a stream of hydrogen in which pulses of carbon monoxide were injected. Activation energies for the methanation reaction and hydrogen desorption from the manganate minerals were obtained and compared with those of pure nickel. Similar energy values indicate that the activity of the nodule materials for the reaction appears to be related to the amount of reducible transition metals present in the samples (ca. 11 wt.-%). Since the activity of the nodule minerals per gram is comparable to that of pure nickel, most of the transition metal ions located between manganese oxide layers appear to be exposed and available to catalyze the reaction.

Cabrera, A. L.; Maple, M. B.; Arrhenius, G.

1990-01-01

147

Synthesis of thiocarbamate salts from amines, sulfur, and carbon monoxide  

SciTech Connect

Sulfur reacts with carbon monoxide and amines without a catalyst at 100-160{degrees}C and 10-100 atm for 1-4 h. The reaction products of primary amines are symmetric ureas. Under the same conditions, secondary amines form thiocarbamic acid salts, which are not converted to tetrasubstituted ureas. In the presence of primary amines at 100-160{degrees}C, they afford trisubstituted ureas, some of whose representatives are pesticides. The same products are formed directly in the carbonylation of a mixture of primary and secondary amines without isolation of intermediate thiocarbamic acid salts. In the presence of catalytic amounts of selenium, the reaction of sulfur with carbon monoxide and amines occurs at atmospheric pressure and affords N-substituted thiocarbamic acid salts from both secondary and primary amines. In the current work the authors present some of the characteristics of these processes. 10 refs., 5 figs., 2 tabs.

Manov-Yuvenskii, V.I.; Kuznetsov, S.L.

1992-05-20

148

Composite catalyst for carbon monoxide and hydrocarbon oxidation  

DOEpatents

A method and composition are disclosed for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdenum, copper, cobalt, manganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

Liu, W.; Flytzani-Stephanopoulos, M.

1996-03-19

149

Multilayer Adsorption of Neon, Hydrogens, and Carbon Monoxide on Graphite  

Microsoft Academic Search

Multilayer adsorption of neon, hydrogens (H _2, HD, and D_2), and carbon monoxide on graphite have been investigated using ellipsometric-coverage vapor-pressure isotherm measurements. Chemical potentials at layer condensations and widths of the layer condensation steps were tabulated, and layer critical points were determined from the temperature dependence of the widths for all five adsorbates. In Ne we do not find

Hong Wu

1995-01-01

150

Carbon monoxide poisoning associated with water pipe smoking.  

PubMed

The water pipe is a means of tobacco consumption widespread in Turkey and Arab countries. We present two patients brought to our emergency department due to a syncopal attack secondary to carbon monoxide toxicity following water pipe use. This rare form of poisoning should be borne in mind by emergency physicians as a differential diagnosis in water pipe smokers. Water pipes should be used where there is adequate ventilation. PMID:21819288

Türkmen, Süha; Eryigit, Umut; Sahin, Aynur; Yeniocak, Selman; Turedi, Suleyman

2011-08-01

151

Acute carbon monoxide poisoning: Emergency management and hyperbaric oxygen therapy  

SciTech Connect

An ice storm in February 1989 resulted in numerous incidences of carbon monoxide poisoning in central Mississippi secondary to exposure to open fires in unventilated living spaces. Sixteen cases were treated during this period at the University of Mississippi Medical Center and 6 received Hyperbaric Oxygen therapy. These 6 cases and the mechanisms of CO poisoning are discussed and recommendations for emergency management are reviewed.10 references.

Severance, H.W.; Kolb, J.C.; Carlton, F.B.; Jorden, R.C.

1989-10-01

152

Severe carbon monoxide poisoning: outcome after hyperbaric oxygen therapy  

Microsoft Academic Search

This paper reports the outcome after carbon monoxide poisoning in 31 consecutive patients treated with mechanical ventilation and hyperbaric oxygen therapy, compared with another study of mechanically ventilated patients treated with normobaric oxygen. We found 16.1% hospital mortality and 3.8% severe short-term memory loss, compared with 30% hospital mortality and 20% incidence of serious neurological deficit after treatment with normobaric

M. Hawkins; J. Harrison; P. Charters

153

Forensic and psychiatric aspects of joint suicide with carbon monoxide.  

PubMed

A case of joint suicide of a young woman and man who became acquainted in a suicide web forum and used this platform to make an appointment to commit suicide together is described. During their investigation, police were able to reconstruct the events by analysing the computer of the deceased women which was also found with the bodies. An indoor charcoal burning unit was used to release carbon monoxide as the method of suicide. PMID:21327571

Laberke, Patrick Johannes; Bock, Horst; Dittmann, Volker; Hausmann, Roland

2011-12-01

154

Quantitative analysis of SCIAMACHY carbon monoxide total column measurements  

Microsoft Academic Search

This paper presents a first quantitative and systematic analysis of one year of SCIAMACHY Carbon Monoxide (CO) total column retrievals from the IMLM algorithm (v6.3) using a chemistry-transport model simulation. The global distribution of modeled and measured CO show similar spatial patterns: a north-south gradient, low CO over mountains, and high CO over emission regions. CO column errors due to

A. T. J. de Laat; A. M. S. Gloudemans; H. Schrijver; J. F. Meirink; I. Aben; M. C. Krol

2006-01-01

155

A rare cause of perinatal asphyxia: maternal carbon monoxide poisoning  

Microsoft Academic Search

Carbon monoxide (CO) intoxication has serious adverse effects to the mother and fetus and a result of intrauterine hypoxia,\\u000a it leads to fetal death or severe neurological sequelae. In this article, a preterm infant who was acutely exposed to CO at\\u000a the 33rd weeks of gestation before delivery was presented. The baby was delivered by emergent cesarean section at the

Hayrettin Yildiz; Esin Aldemir; Emel Altuncu; Muhittin Celik; Sultan Kavuncuoglu

2010-01-01

156

Studies relevant to the catalytic activation of carbon monoxide  

SciTech Connect

Research activity has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key steps in the relevant catalytic cycles. Other investigations of related processes included the application of fast reaction techniques to prepare and to investigate quantitatively reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and other functionalizations. 8 refs.

Ford, P.C.

1991-09-04

157

Continuous monitoring of carbon monoxide in a deep street canyon  

Microsoft Academic Search

The results of a 1-week continuous monitoring campaign of carbon monoxide in a deep street canyon in the city of Naples are reported. CO was selected as a passive pollutant emitted by vehicle exhausts. The geometry of the canyon is: width W=5.8m and height H=33m (aspect ratio AR=H\\/W=5.7). The monitoring campaign was carried out from 14 to 20 June 2006.

Fabio Murena; Giuseppe Favale

2007-01-01

158

Heme oxygenase and carbon monoxide initiate homeostatic signaling  

Microsoft Academic Search

Carbon monoxide (CO), a gaseous second messenger, arises in biological systems during the oxidative catabolism of heme by\\u000a the heme oxygenase (HO) enzymes. Many biological functions of HO, such as regulation of vessel tone, smooth muscle cell proliferation,\\u000a neurotransmission, and platelet aggregation, and anti-inflammatory and antiapoptotic effects have been attributed to its enzymatic\\u000a product, CO. How can such diverse actions

Martin Bilban; Arvand Haschemi; Barbara Wegiel; Beek Y. Chin; Oswald Wagner; Leo E. Otterbein

2008-01-01

159

[Urgent cesarean section in a pregnant woman with carbon monoxide poisoning].  

PubMed

Recognition of carbon monoxide is difficult due to its plain physical-chemical properties. Carbon and gas operating heating systems may cause severe poisoning. Carbon-monoxide intoxication may generate severe hypoxic damage and it may cause death. The authors present the case of severe carbon monoxide poisoning affecting one young child and five adults, including a pregnant woman. Because the availability of hyperbaric oxygen therapy is limited in Hungary, urgent cesarean section was performed to avoid intrauterine hypoxic damage. The authors note that there are no standardized non-invasive methods for measuring fetal carbon-monoxide level and that the level of carbon monoxide accumulation is higher and the clearance is longer in the fetus than in the mother. The pathophysiology of carbon monoxide intoxication and therapeutic options in pregnancy are discussed. Orv. Hetil., 2014, 155(22), 871-875. PMID:24860052

Gara, Edit; Gesztes, Eva; Doroszlai, Richárd; Zacher, Gábor

2014-06-01

160

Carbon monoxide poisoning - Immediate diagnosis and treatment are crucial to avoid complications.  

SciTech Connect

Carbon monoxide is an odorless, colorless, tasteless gas produced by the incomplete combustion of carbon-containing fuels (oil, kerosene, coal, wood) or the inadequate ventilation of natural gas. When carbon monoxide is introduced into the bloodstream, it binds to hemoglobin, reducing the number of binding sites available for oxygen. Carbon monoxide also changes the structure of the hemoglobin molecule, which makes it even more difficult for oxygen that has attached to be released into tissues. The resulting tissue ischemia can lead to organ failure, permanent changes in cognition, or death. Carbon monoxide poisoning is the leading cause of death by poisoning in industrialized countries.

Rosenthal, L.D. [Case Western Reserve University, Cleveland, OH (United States)

2006-03-15

161

Methanation of gas streams containing carbon monoxide and hydrogen  

DOEpatents

Carbon monoxide-containing gas streams having a relatively high concentration of hydrogen are pretreated so as to remove the hydrogen in a recoverable form for use in the second step of a cyclic, essentially two-step process for the production of methane. The thus-treated streams are then passed over a catalyst to deposit a surface layer of active surface carbon thereon essentially without the formation of inactive coke. This active carbon is reacted with said hydrogen removed from the feed gas stream to form methane. The utilization of the CO in the feed gas stream is appreciably increased, enhancing the overall process for the production of relatively pure, low-cost methane from CO-containing waste gas streams.

Frost, Albert C. (Congers, NY)

1983-01-01

162

Atmospheric Trace Gases, Carbon Isotopes, Radionuclides, and Aerosols: Atmospheric Carbon Monoxide Data from the Carbon Dioxide Information Analysis Center (CDIAC)  

DOE Data Explorer

(Scroll down to find Atmospheric Carbon Monoxide, a subheading under the broader heading of Atmospheric Trace Gases, etc.) CDIAC products are indexed and searchable through a customized interface powered by ORNL's Mercury search engine. Products include numeric data packages, publications, trend data, atlases, models, etc. and can be searched for by subject area, keywords, authors, product numbers, time periods, collection sites, spatial references, etc. Some of the collections may also be included in the CDIAC publication Trends Online: A Compendium of Global Change Data. Most data sets, many with numerous data files, are free to download from CDIAC's ftp area. Information related to atmospheric carbon monoxide includes: • Atmospheric CO Concentrations from the CSIRO GASLAB Flask Sampling Network (Trends Online) • MAPS 1994 Correlative Atmospheric CO Mixing Ratios (1998) • Atmospheric Carbon Monoxide Mixing Ratios NOAA Climate Monitoring and Diagnostics Laboratory Cooperative Air Sampling Network, 1988-1993 (1994) Specialized Interface

163

Source and beam performance improvement for carbon implantation with carbon monoxide (CO) gas  

NASA Astrophysics Data System (ADS)

Carbon co-implantation has been widely adopted for better Ultra-Shallow Junction formation in the fabrication of advanced semiconductor devices. Currently, carbon dioxide (CO2) is the primary feed gas for carbon implantation. The primary disadvantage of CO2 is the high oxygen content, which causes significant oxidation of the implant source components resulting in rapid degradation of the source performance. Usually the C+ beam starts to degrade quickly while running continuously with carbon dioxide. Also, some other species' implants, especially boron, are significantly affected after a short duration of CO2 usage. Carbon monoxide (CO) is described here as an alternative carbon source material to CO2. In our testing, CO has demonstrated significant improvements compared to CO2 for both source life and beam performance. Additionally, this paper describes a subatmospheric delivery option for CO. The cylinder package with reliability information is provided.

Tang, Ying; Chambers, Barry; Yedave, Sharad; Sergi, Steve; Sweeney, Joseph; Despres, Joseph; Bishop, Steve

2012-11-01

164

Gas geyser--a cause of fatal domestic carbon monoxide poisoning.  

PubMed

Carbon monoxide is responsible for a large number of accidental domestic poisoning and deaths throughout the world. Domestic carbon monoxide poisoning is rarely reported in India and remains an under recognized problem. The diagnosis of carbon monoxide poisoning is usually based on autopsy findings, circumstantial evidence and estimation of carboxy-haemoglobin in blood. We report a case of fatal accidental carbon monoxide poisoning in a bathroom where an LPG gas water heater was installed recently. Cherry pink discolouration of the body and organs on autopsy suggested carbon monoxide poisoning. Laboratory analysis of blood by UV visible spectrophotometry revealed presence of dangerous levels of carboxy-haemoglobin. Effective preventive measures can help in bringing down the mortality and morbidity associated with carbon monoxide poisoning. PMID:23084315

Mohankumar, T S; Kanchan, Tanuj; Pinakini, K S; Menezes, Ritesh G; Singh, Manisha; Sirohi, Parmendra; Anwar, Naureen

2012-11-01

165

Carbon monoxide fluxes over a managed mountain meadow  

NASA Astrophysics Data System (ADS)

Carbon monoxide (CO) is a toxic trace gas with an atmospheric lifetime of 1-3 months and an average atmospheric concentration of 100 ppb. CO mole fractions exhibit a pronounced seasonal cycle with lows in summer and highs in winter. Carbon monoxide has an indirect global warming potential by increasing the lifetime of methane (CH4), as the main sink of CO is the reaction with the hydroxyl (OH) radical, which in turn is also the main sink for CH4. Regarding the warming potential, it is estimated that 100 kg CO are equivalent to an emission of 5 kg CH4. In addition, carbon monoxide interferes with the building and destruction of ozone. Emission into and uptake from the atmosphere of CO are thus relevant for global climate and regional air quality. Sources and sinks of CO on a global scale are still highly uncertain, mainly due to general scarcity of empirical data and the lack of ecosystem-scale CO exchange measurements, i.e. CO flux data that encompass all sources and sinks within an ecosystem. Here we present eddy covariance CO fluxes over a managed temperate mountain grassland near Neustift, Austria, whereby volume mixing ratios of CO were quantified by a dual-laser mid-infrared quantum cascade laser (QCL). First analyses of fluxes captured in April 2013 showed that the QCL is well able to capture CO fluxes at the study site during springtime. During the same time period, both significant net uptake and deposition of CO were observed, with high emission and deposition fluxes on the order of +/- 5 nmol m-2 s-1, respectively. In addition, CO fluxes exhibited a clear diurnal cycle during certain time periods, indicating a continuous release or uptake of the compound with peak flux rates around noon. In this presentation, we will analyze 12 months of carbon monoxide fluxes between January and December 2013 with regard to possible abiotic and biotic drivers of CO exchange. As an additional step towards a full understanding of the greenhouse gas exchange of the meadow, we will relate observed CO fluxes to concurrently measured CO2, CH4 and N2O exchange rates in terms of CO2-equivalents and - where applicable - carbon.

Hörtnagl, Lukas; Hammerle, Albin; Wohlfahrt, Georg

2014-05-01

166

Material processing with hydrogen and carbon monoxide on Mars  

NASA Astrophysics Data System (ADS)

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol, produced by Fischer-Tropsch chemistry may be useful as a fuel; it is easy to store and handle because it is a liquid at Mars temperatures. The reduction of CO2 to hydrocarbons such as methane or acetylene can be accomplished with hydrogen. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquids. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

Hepp, Aloysius F.; Landis, Geoffrey A.; Linne, Diane L.

167

Material processing with hydrogen and carbon monoxide on Mars  

NASA Astrophysics Data System (ADS)

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol, produced by Fischer-Tropsch chemistry may be useful as a fuel; it is easy to store and handle because it is a liquid at Mars temperatures. The reduction of CO2 to hydrocarbons such as methane or acetylene can be accomplished with hydrocarbons. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquid. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

Hepp, Aloysius F.; Linne, Diane L.; Landis, Geoffrey A.

168

Material processing with hydrogen and carbon monoxide on Mars  

NASA Technical Reports Server (NTRS)

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol, produced by Fischer-Tropsch chemistry may be useful as a fuel; it is easy to store and handle because it is a liquid at Mars temperatures. The reduction of CO2 to hydrocarbons such as methane or acetylene can be accomplished with hydrocarbons. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquid. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

Hepp, Aloysius F.; Linne, Diane L.; Landis, Geoffrey A.

1991-01-01

169

Material processing with hydrogen and carbon monoxide on Mars  

NASA Technical Reports Server (NTRS)

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol, produced by Fischer-Tropsch chemistry may be useful as a fuel; it is easy to store and handle because it is a liquid at Mars temperatures. The reduction of CO2 to hydrocarbons such as methane or acetylene can be accomplished with hydrogen. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquids. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

Hepp, Aloysius F.; Landis, Geoffrey A.; Linne, Diane L.

1991-01-01

170

Application of carbon monoxide diffusing capacity in the mouse lung  

PubMed Central

In the past decade the mouse has become the primary animal model of a variety of lung diseases. To assess various mechanisms underlying such pathologies, it is essential to make functional measurements that can reflect the developing pathology. In this regard, the diffusing capacity for carbon monoxide is a variable that directly reflects structural changes in the lung. Although measurement of single-breath diffusing capacity of the lung for carbon monoxide (DlCO) has also been previously reported in mice by a number of investigators, a number of technical issues have precluded routine and widespread use of this metric in mouse models. In the present report, we describe a means to quickly and simply measure a dimensionless variable closely related to the DlCO in mice, termed a diffusion factor for carbon monoxide (DFCO). The DFCO procedure involves a 9-s lung inflation with tracer gases in an anesthetized mouse, followed by a 1-min gas analysis time. We have tested the approach with two common models of lung pathology, elastase-induced emphysema and bleomycin-induced fibrosis. Results show a significant 15% reduction in DFCO in emphysema, and a 41% reduction in the fibrosis model. Repeat measurements within a mouse were found to be highly reproducible. This pulmonary function test can thus be used to detect structural changes with these pathological models. The method can also be used to measure changes in pulmonary blood volume, since the uptake of CO is highly dependent on this variable in addition to the gas exchange surface area.

Fallica, Jon; Das, Sandhya; Horton, Maureen

2011-01-01

171

Mixing ratios of carbon monoxide in the troposphere  

SciTech Connect

Carbon monoxide (CO) mixing ratios were measured in air samples collected weekly at eight locations. The air was collected as part of the CMDL/NOAA cooperative flask sampling program (Climate Monitoring and Diagnostics Laboratory, formerly Geophysical Monitoring for Climatic Change, Air Resources Laboratory/National Oceanic and Atmospheric Administration) at Point Barrow, Alaska, Niwot Ridge, Colorado, Mauna Loa and Cape Kumakahi, Hawaii, Guam, Marianas Islands, Christmas Island, Ascension Island and American Samoa. Half-liter or 3-L glass flasks fitted with glass piston stopcocks holding teflon O rings were used for sample collection. CO levels were determined within several weeks of collection using gas chromatography followed by mercuric oxide reduction detection, and mixing ratios were referenced against the CMDL/NOAA carbon monoxide standard scale. During the period of study (mid-1988 through December 1990) CO levels were greatest in the high latitudes of the northern hemisphere (mean mixing ratio from January 1989 to December 1990 at Point Barrow was approximately 154 ppb) and decreased towards the south (mean mixing ratio at Samoa over a similar period was 65 ppb). Mixing ratios varied seasonally, the amplitude of the seasonal cycle was greatest in the north and decreased to the south. Carbon monoxide levels were affected by both local and regional scale processes. The difference in CO levels between northern and southern latitudes also varied seasonally. The greatest difference in CO mixing ratios between Barrow and Samoa was observed during the northern winter (about 150 ppb). The smallest difference, 40 ppb, occurred during the austral winter. The annually averaged CO difference between 71[degrees]N and 14[degrees]S was approximately 90 ppb in both 1989 and 1990; the annually averaged interhemispheric gradient from 71[degrees]N to 41[degrees]S is estimated as approximately 95 ppb. 66 refs., 5 figs., 5 tabs.

Novelli, P.C.; Steele, L.P. (Univ. of Colorado, Boulder (United States)); Tans, P.P. (NOAA, Boulder, CO (United States))

1992-12-20

172

Azide binding to carbon monoxide dehydrogenase from Clostridium thermoaceticum  

SciTech Connect

Carbon monoxide dehydrogenase (CODH) plays a central role in a recently discovered pathway of anaerobic CO and CO{sub 2} fixation. In this communication, the EPR properties of a paramagnetic species that results from azide treatment of reduced CODH are explored. Azide, an inhibitor of CO oxidation, was found to dramatically alter the EPR spectrum of center C that is normally observed for untreated samples under reducing conditions. Electron spin echo envelope modulation (ESEEM) measurements show that azide is bound to the new paramagnetic species. 29 refs., 3 figs.

Kumar, M.; Lu, W.P.; Ragsdale, S.W. [Univ. of Nebraska, Lincoln, NE (United States); Smith, A.; McCracken, J. [Michigan State Univ., East Lansing, MI (United States)

1995-03-15

173

Modeling of Carbon Monoxide Removal by Corona Plasma  

NASA Astrophysics Data System (ADS)

Modeling of carbon monoxide (CO) removal by a corona plasma was conducted in this study. The purification efficiency of CO was calculated theoretically and the factors affecting the removal of CO were analyzed. The results showed that the main removal mechanisms of CO were direct dissociation by generated high-energy electrons and indirect oxidation by generated hydroxyl radicals. The purification efficiency of CO was dependent on the plasma parameters, indoor air humidity and initial concentration of CO. Good consistency between the theoretical calculation and the experimental results was observed.

Feng, Jingwei; Sun, Yabing; Zhao, Dayong; Zheng, Zheng; Xu, Yuewu; Yang, Haifeng; Zhu, Hongbiao; Zhou, Xiaoxia

2009-10-01

174

Compact carbon monoxide sensor utilizing a confocal optical cavity.  

NASA Technical Reports Server (NTRS)

The carbon monoxide sensor discussed in this paper utilizes a unique confocal cavity which allows the complete system to be packaged in a small volume suitable for hand-held use. The optical system is the heart of the instrument with equal emphasis placed on the electronics support circuitry, consisting essentially of a thermal infrared pyroelectric detector and lock-in amplifier. The pyroelectric detector offers a major advantage over other thermal detectors, providing a signal-to-noise ratio and detectivity that remain nearly constant over the frequency range from dc to 2000 Hz. Since bias voltage is not required, low frequency noise is not generated in the detector.

Scott, B.; Magyar, J.; Weyant, R.; Hall, J.

1973-01-01

175

Transient PrOx carbon monoxide measurement, control, and optimization  

SciTech Connect

Fuel processing systems for low temperature polymer electrolyte membrane (PEM) fuel cell systems require control of the carbon monoxide concentration to less than 100 ppm to 10 ppm in the anode feed. Conventional hydrocarbon fuel processors use a water-gas shift (WGS) reactor to react CO with water to form H2 and reduce the CO concentration. The CO conversion is limited by equilibrium at the outlet temperature of the WGS reactor. The WGS outlet CO concentration can range from over 1% to 2000 ppm depending on the system and its operating parameters. At these concentrations, CO poisons low temperature PEM fuel cells and the concentrations needs to be reduced further.

Inbody, M. A. (Michael A.); Borup, R. L. (Rodney L.); Tafoya, J. (Jose I.)

2002-01-01

176

Apparent suicidal carbon monoxide poisonings with concomitant prescription drug overdoses.  

PubMed

We report four separate suicides by apparent motor vehicle-related carbon monoxide (CO) poisoning in which complete toxicological analysis showed the absence of, or lower than expected, percent carboxyhemoglobin saturation and high concentrations of concomitant prescription drugs. These cases, within a population of 71 apparent CO suicides from the Wayne County Medical Examiner's Office over 1998-2004, represent cases where additional factors are in play. Multiple modalities (CO poisoning and drug overdose) and/or undetectable carbon dioxide poisoning from the vehicle exhaust of cars manufactured after laws regulating vehicle emissions were enacted are examples of additional factors that require consideration in these selected cases. All four cases demonstrated some degree of decomposition, so the possible loss of CO could not be ruled out. The need for full toxicological analysis in apparent suicidal CO poisoning is emphasized. PMID:16419412

Gupta, Avneesh; Pasquale-Styles, Melissa A; Hepler, Bradford R; Isenschmid, Daniel S; Schmidt, Carl J

2005-10-01

177

Interaction of carbon monoxide and hydrogen with the (1010) face of ruthenium  

SciTech Connect

The interaction was studied at 23.5, 200, and -135/sup 0/C with low energy electron diffraction (LEED) and Auger electron spectroscopy. (AES). Carbon monoxide adsorbs associatively at 23.5/sup 0/C, but is apparently dissociated by the LEED beam and hydrogen adsorbed from the ambient after a few minutes for less than 10 Langmuirs of carbon monoxide. For large doses of carbon monoxide at 23.5/sup 0/C, 10 Langmuirs or more, the LEED beam does not disociate carbon monoxide, but carbon monoxide and hydrogen adsorbed from the ambient do appear to be removed from the surface by the LEED beam. Carbon monoxide and hydrogen on the surface together will react and form surface complexes with distinctive LEED patterns at 23.5/sup 0/C though some of the interactions appear to be LEED beam induced. If sufficient hydrogen is present, some of these complexes are lost from the surface probably as methane and water. Carbon monoxide will react with itself and hydrogen at 23.5/sup 0/C with carbon being lost from the surface probably as carbon dioxide. At 200/sup 0/C, neither carbon monoxide nor hydrogen will absorb on Ru (1010) in significant amounts at the low dose pressures used. However, if the Ru(1010) crystal is allowed to cool below 70/sup 0/C, ambient carbon monoxide and hydrogen will adsorb on Ru (1010) and form LEED patterns like those formed at 23.5/sup 0/C. At -135/sup 0/C, carbon monoxide will react with itself and hydrogen readily most of the time producing surface complexes with distinctive LEED paterns. If a moderate amount of hydrogen is present, some of these complexes are lost from the surface, probably as methane. If a large amount of hydrogen is present, some of these complexes are lost from the surface probably as carbon dioxdie. 17 figures, 8 tables.

Tomcsik, T.L.

1979-01-01

178

Portable device for monitoring consistency of carbon monoxide  

NASA Astrophysics Data System (ADS)

The necessity to nondestructively monitor concentration of carbon monoxide (CO), which is a colorless, tasteless and poisonous gas and is harmful to people, is disclosed. The portable device for monitoring concentration of CO plays an important role in health care and environment supervising for civil and industrial purposes. A basic circuit-based principle for the implementation of the device is presented with a detailed analysis for the key issues in designing. Specifically, the designing for the preamplifier is of great importance to the performance of the device. There is also introduced a method for getting standard voltage value from the micro-ampere current signal outputted from a carbon monoxide sensor and for restraining other gases to exert influence on the CO monitoring. Meanwhile, the paper teaches an anti-jamming technique for eliminating interference between analog and digital circuits within a very small system. In said device, a multi-function alarm circuit, which periodically performing its self-checking function, produces alarm with sound and light if the power of a battery is insufficient or the concentration of CO is detected to be over a set threshold. In addition, the major characteristics and applications for the device are also presented.

Zheng, Qingyu; Liang, Fuping; Liu, Gang; Wang, Xiaofei

2002-06-01

179

Neuroprotective, neurotherapeutic, and neurometabolic effects of carbon monoxide  

PubMed Central

Studies in animal models show that the primary mechanism by which heme-oxygenases impart beneficial effects is due to the gaseous molecule carbon monoxide (CO). Produced in humans mainly by the catabolism of heme by heme-oxygenase, CO is a neurotransmitter important for multiple neurologic functions and affects several intracellular pathways as a regulatory molecule. Exogenous administration of inhaled CO or carbon monoxide releasing molecules (CORM’s) impart similar neurophysiological responses as the endogenous gas. Its’ involvement in important neuronal functions suggests that regulation of CO synthesis and biochemical properties may be clinically relevant to neuroprotection and the key may be a change in metabolic substrate from glucose to lactate. Currently, the drug is under development as a therapeutic agent and safety studies in humans evaluating the safety and tolerability of inhaled doses of CO show no clinically important abnormalities, effects, or changes over time in laboratory safety variables. As an important therapeutic option, inhaled CO has entered clinical trials and its clinical role as a neuroprotective and neurotherapeutic agent has been suggested. In this article, we review the neuroprotective effects of endogenous CO and discuss exogenous CO as a neuroprotective and neurotherapeutic agent.

2012-01-01

180

Bilateral brachial plexus injury following acute carbon monoxide poisoning  

PubMed Central

Background Carbon monoxide (CO) intoxication is a leading cause of severe neuropsychological impairments. Peripheral nerve injury has rarely been reported. It consists usually in a demyelinating polyneuropathy or mononeuropathy affecting mainly the lower limbs. Isolated involvement of both upper extremities has been described in only 4 patients related to root damage. We report the first case of bilateral brachial plexus injury following CO poisoning and review all previous CO-induced neuropathy described in literature. Case presentation After being unconscious for three hours, a 42 years old man experienced bilateral brachial weakness associated with edema of the face and the upper limbs. Neurological examination showed a brachial diplegia, distal vibratory, thermic and algic hypoesthesia, deep tendon areflexia in upper limbs. There was no sensory or motor deficit in lower extremities. No cognitive disturbances were detected. Creatine kinase was elevated. Electroneuromyogram patterns were compatible with the diagnosis of bilateral C5 D1 brachial axonal plexus injury predominant on the left side. Clinical course after hyperbaric oxygen therapy was marked by a complete recovery of neurological disorders. Conclusion Peripheral neuropathy is an unusual complication of CO intoxication. Bilateral brachial plexus impairment is exceptional. Various mechanisms have been implicated including nerve compression secondary to rhabdomyolysis, nerve ischemia due to hypoxia and direct nerve toxicity of carbon monoxide. Prognosis is commonly excellent without any sequelae.

2013-01-01

181

A carbon monoxide passive sampler: Research and development needs  

SciTech Connect

In rare instances, carbon monoxide (CO) levels in houses can reach dangerously high concentrations, causing adverse health effects ranging from mild headaches to, under extreme conditions, death. Hundreds of fatal accidental carbon monoxide poisonings occur each year primarily due to the indoor operation of motor vehicles, the indoor use of charcoal for cooking, the operation of malfunctioning vented and unvented combustion appliances, and the misuse combustion appliances. Because there is a lack of simple, inexpensive, and accurate field sampling instrumentation, it is difficult for gas utilities and researchers to conduct field research studies designed to quantify the concentrations of CO in residences. Determining the concentration of CO in residences is the first step towards identifying the high risk appliances and high-CO environments which pose health risks. Thus, there exists an urgent need to develop and field-validate a CO-quantifying technique suitable for affordable field research. A CO passive sampler, if developed, could fulfill these requirements. Existing CO monitoring techniques are discussed as well as three potential CO-detection methods for use in a CO passive sampler. Laboratory and field research needed for the development and validation of an effective and cost-efficient CO passive sampler are also discussed.

Traynor, G.W.; Apte, M.G.; Diamond, R.C.; Woods, A.L.

1991-11-01

182

Neuroprotective, neurotherapeutic, and neurometabolic effects of carbon monoxide.  

PubMed

Studies in animal models show that the primary mechanism by which heme-oxygenases impart beneficial effects is due to the gaseous molecule carbon monoxide (CO). Produced in humans mainly by the catabolism of heme by heme-oxygenase, CO is a neurotransmitter important for multiple neurologic functions and affects several intracellular pathways as a regulatory molecule. Exogenous administration of inhaled CO or carbon monoxide releasing molecules (CORM's) impart similar neurophysiological responses as the endogenous gas. Its' involvement in important neuronal functions suggests that regulation of CO synthesis and biochemical properties may be clinically relevant to neuroprotection and the key may be a change in metabolic substrate from glucose to lactate. Currently, the drug is under development as a therapeutic agent and safety studies in humans evaluating the safety and tolerability of inhaled doses of CO show no clinically important abnormalities, effects, or changes over time in laboratory safety variables. As an important therapeutic option, inhaled CO has entered clinical trials and its clinical role as a neuroprotective and neurotherapeutic agent has been suggested. In this article, we review the neuroprotective effects of endogenous CO and discuss exogenous CO as a neuroprotective and neurotherapeutic agent. PMID:23270619

Mahan, Vicki L

2012-01-01

183

Carbon monoxide:methylene blue oxidoreductase from Pseudomonas carboxydovorans.  

PubMed Central

The enzyme carbon monoxide:methylene blue oxidoreductase from CO autotrophically grown cells of Pseudomonas carboxydovorans strain OM5, was purified to homogeneity. The enzyme was obtained in 26% yield and was purified 36-fold. The enzyme was stable for at least 6 days, had a molecular weight of 230,000, gave a single protein and activity band on polyacrylamide gel electrophoresis, and was homogeneous by the criterion of sedimentation equilibrium. Sodium dodecyl sulfate gel electrophoresis revealed a single band of molecular weight 107,000. Carbon monoxide:methylene blue oxidoreductase did not catalyze reduction of pyridine or flavin nucleotides but catalyzed the oxidation of CO to CO2 in the presence of methylene blue, thionine, toluylene blue, dichlorophenolindophenol, or pyocyanine under strictly anaerobic conditions. The visible spectrum revealed maxima at 405 and 470 nm. The millimolar extinction coefficients were 43.9 (405 nm) and 395.5 (275 nm), respectively. Absorption at 470 nm decreased in the presence of dithionite, and the spectrum was not affected by the substrate CO. Maximum reaction rates were found at pH 7.0 and 63 degrees C; temperature dependence followed the Arrhenius equation, with an activation energy (delta H degree) of 36.8 kJ/mol (8.8 kcal/mol). The apparent Km was 53 microM for CO. The purified enzyme was incapable of oxidizing methane, methanol, or formaldehyde in the presence of methylene blue as electron acceptor. Images

Meyer, O; Schlegel, H G

1980-01-01

184

Combustion characteristics of hydrogen. Carbon monoxide based gaseous fuels  

NASA Technical Reports Server (NTRS)

An experimental rig program was conducted with the objective of evaluating the combuston performance of a family of fuel gases based on a mixture of hydrogen and carbon monoxide. These gases, in addition to being members of a family, were also representative of those secondary fuels that could be produced from coal by various gasification schemes. In particular, simulated Winkler, Lurgi, and Blue-water low and medium energy content gases were used as fuels in the experimental combustor rig. The combustor used was originally designed as a low NOx rich-lean system for burning liquid fuels with high bound nitrogen levels. When used with the above gaseous fuels this combustor was operated in a lean-lean mode with ultra long residence times. The Blue-water gas was also operated in a rich-lean mode. The results of these tests indicate the possibility of the existence of an 'optimum' gas turbine hydrogen - carbon monoxide based secondary fuel. Such a fuel would exhibit NOx and high efficiency over the entire engine operating range. It would also have sufficient stability range to allow normal light-off and engine acceleration. Solar Turbines Incorporated would like to emphasize that the results presented here have been obtained with experimental rig combustors. The technologies generated could, however, be utilized in future commercial gas turbines.

Notardonato, J. J.; White, D. J.; Kubasco, A. J.; Lecren, R. T.

1981-01-01

185

Prognosis of carbon monoxide poisoning in 15 patients, previously mentally ill  

Microsoft Academic Search

Carbon monoxide poisoning is a problem ilnportant to psychiatrists inasmuch as illuminating gas or motor exhaust gas is frequently used in suicide attempts by mentally ill persons and by others who subsequently require institutional care. The neurological and psychiatric manifestations of carbon monoxide intoxication have been most adequately described. However, there have been but few studies made to determine the

Robert J. van Amberg

1942-01-01

186

Removal of carbon monoxide. Physical adsorption on natural and synthetic zeolites  

NASA Technical Reports Server (NTRS)

The utilization of natural zeolite materials in the elimination of polluting gases is investigated. Carbon monoxide pollution is emphasized because its concentration may reach dangerous levels in places such as vehicle tunnels, underground parking lots, etc. The elimination of carbon monoxide is also of interest in some industrial processes relating to the production of pure gases.

Alfani, F.; Greco, G., Jr.; Iroio, G.

1982-01-01

187

Carbon monoxide and nitrogen dioxide exposures in indoor ice skating rinks  

Microsoft Academic Search

Exposures to carbon monoxide (CO) and nitrogen dioxide (NO2) were determined in seven enclosed ice skating rinks and an outdoor rink. The uptake of CO was also determined by the difference in alveolar CO concentration of the non?smoking hockey players before and after games. Carbon monoxide concentrations in enclosed rinks ranged from 4 to 117 ppm and NO2 concentrations from

Kiyoung Lee; Yukio Yanagisawa; John D. Spengler; Satoshi Nakai

1994-01-01

188

CARBON MONOXIDE CONCENTRATIONS IN FOUR U.S. CITIES DURING THE WINTER OF 1981  

EPA Science Inventory

Portable monitors were used to measure time averaged personal exposures (10-30 min) to carbon monoxide. Data were collected from January through March 1981 in four cities where carbon monoxide ambient levels in excess of National Ambient Air Quality Standards have been reported: ...

189

Carbon Monoxide-Releasing Molecules Characterization of Biochemical and Vascular Activities  

Microsoft Academic Search

Carbon monoxide (CO) is generated in living organisms during the degradation of heme by the enzyme heme oxygenase, which exists in constitutive (HO-2 and HO-3) and inducible (HO-1) isoforms. Carbon monoxide gas is known to dilate blood vessels in a manner similar to nitric oxide and has been recently shown to possess antiinflammatory and antiapoptotic properties. We report that a

Roberto Motterlini; James E. Clark; Roberta Foresti; Padmini Sarathchandra; Brian E. Mann; Colin J. Green

2010-01-01

190

New Physiological Importance of Two Classic Residual Products: Carbon Monoxide and Bilirubin  

Microsoft Academic Search

Heme oxygenase the rate-limiting step in the degradation of heme to bilirubin, generates carbon monoxide. This gaseous molecule plays important roles in neuronal signaling and modulation of vascular tone. Additionally, carbon monoxide is involved in some pathological conditions (e.g., ischemia, endotoxic shock, excitotoxicity) as a protective or toxic factor. Bilirubin, another heme metabolite, exhibits intriguing biological activities as an antioxidant,

Gilca Marilena

1997-01-01

191

Regional studies of potential carbon monoxide sources based on space shuttle and aircraft measurements  

Microsoft Academic Search

Carbon monoxide measurements made from the space shuttle show maxima over South America, central Africa, the eastern Mediterranean, and China. The maxima appear to be associated with either concomitant or prior convection in the air masses which carries boundary layer air into the upper troposphere. Previous aircraft measurements of carbon monoxide and ozone over South America are shown to be

R. E. Newell; S. T. Shipley; V. S. Connors; H. G. Reichle

1988-01-01

192

Photolysis of the Carbon Monoxide Complex of Myoglobin: Nanosecond Time Resolved Crystallography  

Microsoft Academic Search

The biological activity of macromolecules is accompanied by rapid structural changes. The photosensitivity of the carbon monoxide complex of myoglobin was used at the European Synchrotron Radiation Facility to obtain pulsed, Laue x-ray diffraction data with nanosecond time resolution during the process of heme and protein relaxation after carbon monoxide photodissociation and during rebinding. These time-resolved experiments reveal the structures

Vukica Srajer; Tsu-Yi Teng; Thomas Ursby; Claude Pradervand; Zhong Ren; Shin-Ichi Adachi; Wilfried Schildkamp; Dominique Bourgeois; Michael Wulff; Keith Moffat

1996-01-01

193

Secondhand cigarette smoke as a cause of chronic carbon monoxide poisoning  

SciTech Connect

Symptoms of carbon monoxide poisoning in a nonsmoking patient continued for several years until her husband stopped smoking cigarettes near her. Carbon monoxide poisoning should be considered in non-smokers when characteristic toxic symptoms occur (ie, lethargy, irritability, headache, blurred vision, slowed reaction time, and decreased concentration). Toxicity may develop simply from breathing second-hand smoke.

Kachulis, C.J.

1981-07-01

194

Nitric oxide but not carbon monoxide is continuously released in the human nasal airways  

Microsoft Academic Search

Nitric oxide but not carbon monoxide is continuously released in the human nasal airways. J.O.N. Lundberg, J. Palm, K. Alving. #ERS Journals Ltd 2002. ABSTRACT: Results from different laboratories indicate that nitric oxide (NO) and carbon monoxide (CO) coexist in the human airways both in health and disease. These gases are present in exhaled human breath and high concentrations of

J. O. N. Lundberg; J. Palm; K. Alving

2002-01-01

195

Effects of carbon monoxide releasing molecule-liberated CO on severe acute pancreatitis in rats  

Microsoft Academic Search

Recent studies have suggested that exogenously administered carbon monoxide (CO) is beneficial for resolution of acute inflammation. Severe acute pancreatitis (SAP) is an inflammatory condition which leads to a systemic inflammatory response syndrome (SIRS). In this study, we investigated the role of CO liberated from carbon monoxide releasing molecule-2 (CORM-2) in rats with SAP. SAP was induced by retrograde infusion

Ping Chen; Bei Sun; Hua Chen; Gang Wang; Shangha Pan; Rui Kong; Xuewei Bai; Shuangjia Wang

2010-01-01

196

Inhalation Toxicology. 11. The Effect of Elevated Temperature on Carbon Monoxide Toxicity.  

National Technical Information Service (NTIS)

Laboratory rats were exposed (a) to experimental concentrations of carbon monoxide in air at ambient temperature, (b) to elevated temperature atmospheres from 40 deg C to 60 deg C, and (c) to selected carbon monoxide (CO) concentrations at the elevated te...

B. R. Endecott D. C. Sanders

1990-01-01

197

Secondhand cigarette smoke as a cause of chronic carbon monoxide poisoning  

Microsoft Academic Search

Symptoms of carbon monoxide poisoning in a nonsmoking patient continued for several years until her husband stopped smoking cigarettes near her. Carbon monoxide poisoning should be considered in non-smokers when characteristic toxic symptoms occur (ie, lethargy, irritability, headache, blurred vision, slowed reaction time, and decreased concentration). Toxicity may develop simply from breathing second-hand smoke.

Kachulis

1981-01-01

198

METEOROLOGICAL FACTORS RESPONSIBLE FOR HIGH CO (CARBON MONOXIDE) LEVELS IN ALASKAN CITIES  

EPA Science Inventory

High winter carbon monoxide levels in Anchorage, as in Fairbanks, are due to intense nocturnal (ground-based) inversions persisting through the periods of maximum emissions and at times throughout the day. The problem is exacerbated by the large amounts of carbon monoxide emitted...

199

Analysis of Multiplatform CO (Carbon Monoxide) Measurements During Trace-P Mission.  

National Technical Information Service (NTIS)

Carbon monoxide is considered mission critical (TRACE-P NRA) because it is one of the gases involved in controlling the oxidizing power of the atmosphere and, as a tracer gas, is valuable in interpreting mission data sets. Carbon monoxide exhibits interan...

N. S. Pougatchev

2004-01-01

200

A STUDY TO EVALUATE CARBON MONOXIDE AND HYDROGEN SULFIDE CONTINUOUS EMISSION MONITORS AT AN OIL REFINERY  

EPA Science Inventory

An eleven month field evaluation was done on five hydrogen sulfide and four carbon monoxide monitors located at an oil refinery. The hydrogen sulfide monitors sampled a fuel gas feed line and the carbon monoxide monitors sampled the emissions from a fluid cat cracker (FCC). Two o...

201

Methane and Carbon Monoxide Gas Detection system based on semiconductor sensor  

Microsoft Academic Search

One of the most important actual problems in the gas detection field is that there are strong demands for gas methane leak detection and CO (carbon monoxide) detection to prevent explosions or CO poisoning accidents. In this sense, the present paper describes technical characteristics, test results, and a concluding application for methane and carbon monoxide based gas detection using a

E. Cordos; L. Ferenczi; S. Cadar; S. Costiug; G. Pitl; A. Aciu; A. Ghita; M. Chintoanu

2006-01-01

202

Study on reaction rates for methanol synthesis from carbon monoxide, carbon dioxide, and hydrogen  

Microsoft Academic Search

The reaction rates for methanol synthesis from carbon monoxide, carbon dioxide, and hydrogen over a copper-zinc-based catalyst were measured under the following conditions: temperature, 210-300°C; pressure, 4-10 MPa, feed gas composition Hâ\\/CO 2.7-720, Hâ\\/COâ, 4.3-120, COâ\\/CO, 0.05-180 (in moles). It was concluded that direct methanol production from COâ takes place under the above conditions in addition to the two well-known

M. Takagawa; M. Ohsugi

1987-01-01

203

Sublimation rates of carbon monoxide and carbon dioxide from comets at large heliocentric distances  

NASA Technical Reports Server (NTRS)

Using a simple model for outgassing from a small flat surface area, the sublimation rates of carbon monoxide and carbon dioxide, two species more volatile than water ice that are known to be present in comets, are calculated for a suddenly activated discrete source on the rotating nucleus. The instantaneous sublimation rate depends upon the comet's heliocentric distance and the Sun's zenith angle at the location of the source. The values are derived for the constants of CO and CO2 in an expression that yields the local rotation-averaged sublimation rate as a function of the comet's spin parameters and the source's cometocentric latitude.

Sekanina, Zdenek

1992-01-01

204

Air pollution: sensitive detection of ten pollutant gases by carbon monoxide and carbon dioxide lasers.  

PubMed

Detection sensitivities of a few parts per billion for ten gaseous pollutants have been evaluated by measuring the strength of the absorption of infrared radiation from carbon monoxide and carbon dioxide lasers. Ethylene concentrations as small as 5 parts per billion have been detected in air. The measured absorption strengths indicate that in mixtures of pollutants, such as nitrogen dioxide and water vapor, the sensitivity is reduced by overlapping absorption bands. However, calculations indicate that it should be possible to detect nitrogen dioxide concentrations of 0.01 part per million in the presence of water vapor concentrations of 105 parts per million. PMID:5035485

Kreuzer, L B; Kenyon, N D; Patel, C K

1972-07-28

205

Cyclic process for producing methane from carbon monoxide with heat removal  

DOEpatents

Carbon monoxide-containing gas streams are converted to methane by a cyclic, essentially two-step process in which said carbon monoxide is disproportionated to form carbon dioxide and active surface carbon deposited on the surface of a catalyst, and said carbon is reacted with steam to form product methane and by-product carbon dioxide. The exothermic heat of reaction generated in each step is effectively removed during each complete cycle so as to avoid a build up of heat from cycle-to-cycle, with particularly advantageous techniques being employed for fixed bed, tubular and fluidized bed reactor operations.

Frost, Albert C. (Congers, NY); Yang, Chang-lee (Spring Valley, NY)

1982-01-01

206

Carbon monoxide exposure of subjects with documented cardiac arrhythmias. Research report, August 1987-July 1991  

SciTech Connect

The authors studied 30 subjects with well-documented coronary artery disease who had an average of at least 30 ventricular ectopic beats per hour over a 20-hour monitoring interval. Subjects were selected and enrolled in a randomized double-blind study; the carbon monoxide exposure was designed to result in 3% or 5% carboxyhemoglobin levels, as measured by gas chromatography. Total and repetitive ventricular arrhythmias were measured for four specific time intervals: (1) two hours before carbon monoxide exposure; (2) during the two-hour carbon monoxide exposure; (3) six hours after carbon monoxide exposure; and (4) approximately 10 hours after exposure, or the remaining recording interval on the Holter monitor. There was no increase in ventricular arrhythmia frequency after carbon monoxide exposure, regardless of the level of carboxyhemoglobin or the type of activity. During steady-state conditions at rest, the number of ventricular ectopic beats per hour was 115 + or - 153 (SD) for room air exposure (0.7% carboxyhemoglobin), 121 + or - 171 for the lower carbon monoxide exposure (3.2% carboxyhemoglobin), and 94 + or - 129 for the higher carbon monoxide exposure (5.1% carboxyhemoglobin). The frequency of complex ventricular ectopy was not altered at the levels of carbon monoxide studied. Secondary analysis of the impact of carbon monoxide on ventricular ectopic beat frequency stratified by baseline ejection fraction, baseline ventricular ectopic beat frequency, and exercise-induced ST-segment changes did not indicate an effect of carbon monoxide on ventricular arrhythmias. However, patients with symptomatic ventricular arrhythmias and symptomatic myocardial ischemia were excluded from the present study.

Chaitman, B.R.; Dahms, T.E.; Byers, S.; Carroll, L.W.; Younis, L.T.

1992-09-01

207

Carbon monoxide-related deaths from 1984 to 1993 in Vienna, Austria.  

PubMed

Carbon monoxide poisoning occurs frequently in industrialized countries. Between 1970 and 1978 in Vienna, the capital of Austria, carbon-monoxide-rich coal gas was replaced with natural gas. Despite this fact, people still die of unintentional carbon monoxide poisoning. The main purpose of this study was to determine the reasons for unintentional carbon monoxide-related deaths, and further to describe the epidemiology of these fetal poisonings in Vienna between 1984 and 1993. A secondary purpose was to investigate whether intentional carbon monoxide poisoning still plays a role among suicides as was the case up to the 1970s. For this purpose we analyzed carbon monoxide-related deaths in Vienna from 1984 to 1993, based on actual autopsy reports of postmortems performed at the Viennese Institute of Forensic Medicine. Deaths due to fire were excluded. The main reason for unintentional carbon monoxide-related deaths in Vienna between 1984 and 1993 was flueless gas-fueled water heating appliances, overused especially by old people during the cold period of the year. The frequency of unintentional carbon monoxide-related deaths in 1993 was almost as high as in 1984. A total of 53% of deceased persons were over age 60. Most fatal carbon monoxide poisoning occurred during the cold period of the year. Suicides decreased significantly during the investigation period. In 76% of these deaths car exhaust fumes were inhaled, especially by men. In conclusion, we recommend programs to prevent unintentional carbon monoxide-related deaths. These programs should especially target the elderly. Flueless gas boilers should not be overused. Furthermore, apartments should be aired sufficiently, even during the cold period of the year.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7782741

Risser, D; Schneider, B

1995-05-01

208

Reactivity of carbon monoxide dehydrogenase from Rhodospirillum rubrum with carbon dioxide, carbonyl sulfide, and carbon disulfide.  

PubMed

The reactivities of CO2 and the related compounds COS and CS2 with the nickel- and iron- sulfur-containing carbon monoxide dehydrogenase (CODH) from Rhodospirillum rubrum have been investigated. Both CO2 and COS were substrates for CODH in a reductant-dependent reaction resulting in the formation of CO. CO2 was reduced to CO and H2O, while COS was reduced to CO and H2S. CO was a potent inhibitor of CO2 reduction at dissolved concentrations as low as 1 microM, but this inhibition could be prevented by quantitatively trapping CO as it was formed by including reduced hemoglobin in the assays. The addition of hemoglobin to the assays also allowed the formation of CO to be monitored in real time by following the decrease in absorbance at 433 nm resulting from carboxyhemoglobin formation. A variety of low-potential reductants, including dithionite, titanium(III) citrate, and dithionite-reduced viologens (methyl and benzyl), were suitable electron donors for the reduction of CO2 and COS. Dithionite-reduced methyl viologen supported the highest rates of CO2 and COS reduction, and the stimulation of CO2 reduction (170-fold increased rate over dithionite alone) was much more dramatic than the stimulation of COS reduction (2.6-fold increased rate over dithionite alone). CO2 was reduced to CO with a Km for CO2 of 190 microM and a Vmax of 44 mumol of CO formed min-1 (mg of protein)-1, while COS was reduced with a Km for COS of 2.2 microM and a Vmax of 0.51 mumol of CO formed min-1 (mg of protein)-1.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7727395

Ensign, S A

1995-04-25

209

Triton's Summer Sky of Methane and Carbon Monoxide  

NASA Astrophysics Data System (ADS)

According to the first ever infrared analysis of the atmosphere of Neptune's moon Triton, summer is in full swing in its southern hemisphere. The European observing team used ESO's Very Large Telescope and discovered carbon monoxide and made the first ground-based detection of methane in Triton's thin atmosphere. These observations revealed that the thin atmosphere varies seasonally, thickening when warmed. "We have found real evidence that the Sun still makes its presence felt on Triton, even from so far away. This icy moon actually has seasons just as we do on Earth, but they change far more slowly," says Emmanuel Lellouch, the lead author of the paper reporting these results in Astronomy & Astrophysics. On Triton, where the average surface temperature is about minus 235 degrees Celsius, it is currently summer in the southern hemisphere and winter in the northern. As Triton's southern hemisphere warms up, a thin layer of frozen nitrogen, methane, and carbon monoxide on Triton's surface sublimates into gas, thickening the icy atmosphere as the season progresses during Neptune's 165-year orbit around the Sun. A season on Triton lasts a little over 40 years, and Triton passed the southern summer solstice in 2000. Based on the amount of gas measured, Lellouch and his colleagues estimate that Triton's atmospheric pressure may have risen by a factor of four compared to the measurements made by Voyager 2 in 1989, when it was still spring on the giant moon. The atmospheric pressure on Triton is now between 40 and 65 microbars - 20 000 times less than on Earth. Carbon monoxide was known to be present as ice on the surface, but Lellouch and his team discovered that Triton's upper surface layer is enriched with carbon monoxide ice by about a factor of ten compared to the deeper layers, and that it is this upper "film" that feeds the atmosphere. While the majority of Triton's atmosphere is nitrogen (much like on Earth), the methane in the atmosphere, first detected by Voyager 2, and only now confirmed in this study from Earth, plays an important role as well. "Climate and atmospheric models of Triton have to be revisited now, now that we have found carbon monoxide and re-measured the methane," says co-author Catherine de Bergh. Of Neptune's 13 moons, Triton is by far the largest, and, at 2700 kilometres in diameter (or three quarters the Earth's Moon), is the seventh largest moon in the whole Solar System. Since its discovery in 1846, Triton has fascinated astronomers thanks to its geologic activity, the many different types of surface ices, such as frozen nitrogen as well as water and dry ice (frozen carbon dioxide), and its unique retrograde motion [1]. Observing the atmosphere of Triton, which is roughly 30 times further from the Sun than Earth, is not easy. In the 1980s, astronomers theorised that the atmosphere on Neptune's moon might be as thick as that of Mars (7 millibars). It wasn't until Voyager 2 passed the planet in 1989 that the atmosphere of nitrogen and methane, at an actual pressure of 14 microbars, 70 000 times less dense than the atmosphere on Earth, was measured. Since then, ground-based observations have been limited. Observations of stellar occultations (a phenomenon that occurs when a Solar System body passes in front of a star and blocks its light) indicated that Triton's surface pressure was increasing in the 1990's. It took the development of the Cryogenic High-Resolution Infrared Echelle Spectrograph (CRIRES) at the Very Large Telescope (VLT) to provide the team the chance to perform a far more detailed study of Triton's atmosphere. "We needed the sensitivity and capability of CRIRES to take very detailed spectra to look at the very tenuous atmosphere," says co-author Ulli Käufl. The observations are part of a campaign that also includes a study of Pluto [eso0908]. Pluto, often considered a cousin of Triton and with similar conditions, is receiving renewed interest in the light of the carbon monoxide discovery, and astronomers are racing to find this chemical o

2010-04-01

210

Delayed death following carbon monoxide poisoning. A case report.  

PubMed

The body of a deceased woman was found in a car. The circumstances were typical for suicidal carbon monoxide (CO) poisoning by inhalation of exhaust gases, except that the vacuum cleaner hose had become detached from the exhaust. Autopsy revealed only decompositional changes. No CO or other drugs were detected. Hypoxic changes were present in the cortex and hippocampus, with an age of 2-3 days. It is consistent that this woman inhaled sufficient CO to cause coma, at which stage the hose became detached, and that she then exhaled CO over the next 2-3 days before finally dying. Delayed death following CO poisoning is an uncommon occurrence. This case is reported because of its unusual nature. PMID:8166113

Opeskin, K; Drummer, O H

1994-03-01

211

Technique for measuring carbon monoxide uptake in mice  

SciTech Connect

A new method has been developed for measuring carbon monoxide (CO) uptake in mice. Each animal was placed in a syringe and allowed to rebreathe a mixture of CO and helium (He) for 60 s. CO uptake was detemined from a comparison of CO and He concentrations before and after rebreathing. Weight specific CO uptake increased with body weight in CBA mice weighing between 20 to 35 gr. In larger mice, size dependence was less marked, although a slight fall in CO uptake was observed in older animals. Anaesthesia reduced ventilatory rate and CO uptake to a variable extent. The method is reproducible, non-invasive and does not require anaesthesia; consequently, it can be used to study serial changes in lung function. It is sensitive enough to detect lung damage in CBA mice following 16 Gy total body irradiation. Values of diffusing capacity obtained for mice using this method are consistent with published values.

Depledge, M.H.; Collis, C.H.; Chir, B.; Barrett, A.

1981-04-01

212

Size-dependent dissociation of carbon monoxide on cobalt nanoparticles.  

PubMed

In situ soft X-ray absorption spectroscopy (XAS) was employed to study the adsorption and dissociation of carbon monoxide molecules on cobalt nanoparticles with sizes ranging from 4 to 15 nm. The majority of CO molecules adsorb molecularly on the surface of the nanoparticles, but some undergo dissociative adsorption, leading to oxide species on the surface of the nanoparticles. We found that the tendency of CO to undergo dissociation depends critically on the size of the Co nanoparticles. Indeed, CO molecules dissociate much more efficiently on the larger nanoparticles (15 nm) than on the smaller particles (4 nm). We further observed a strong increase in the dissociation rate of adsorbed CO upon exposure to hydrogen, clearly demonstrating that the CO dissociation on cobalt nanoparticles is assisted by hydrogen. Our results suggest that the ability of cobalt nanoparticles to dissociate hydrogen is the main parameter determining the reactivity of cobalt nanoparticles in Fischer-Tropsch synthesis. PMID:23339635

Tuxen, Anders; Carenco, Sophie; Chintapalli, Mahati; Chuang, Cheng-Hao; Escudero, Carlos; Pach, Elzbieta; Jiang, Peng; Borondics, Ferenc; Beberwyck, Brandon; Alivisatos, A Paul; Thornton, Geoff; Pong, Way-Faung; Guo, Jinghua; Perez, Ruben; Besenbacher, Flemming; Salmeron, Miquel

2013-02-13

213

Carbon Monoxide: To Boldly Go Where NO Has Gone Before  

NSDL National Science Digital Library

The discovery that nitric oxide (NO) gas acts as a physiological regulator of blood vessel tone represented a milestone in modern biological research. Carbon monoxide (CO), a similar gas, is produced by living cells as an endogenous by-product of heme degradation. Long thought to represent a metabolic waste, endogenous CO, like NO, has attracted much recent attention as a potential physiological regulator. The processes affected by CO include neurotransmission, vasorelaxation, and the regulation of cell growth or death. The mechanisms by which CO affects such biological processes include the production of cyclic nucleotide second messengers and the modulation of protein kinase–dependent signal transduction cascades. Low concentrations of exogenous CO have been shown to confer potent protection to cells and tissues in a number of disease models, offering the promise of future therapeutic applications for CO.

Stefan W. Ryter (University of Pittsburgh School of Medicine;Department of Medicine REV); Danielle Morse (University of Pittsburgh School of Medicine;Department of Medicine REV); Augustine M. K. Choi (University of Pittsburgh School of Medicine;Department of Medicine REV)

2004-04-27

214

Carbon monoxide measurement in the global atmospheric sampling program  

NASA Technical Reports Server (NTRS)

The carbon monoxide measurement system used in the NASA Global Atmospheric Sampling Program (GASP) is described. The system used a modified version of a commercially available infrared absorption analyzer. The modifications increased the sensitivity of the analyzer to 1 ppmv full scale, with a limit of detectability of 0.02 ppmv. Packaging was modified for automatic, unattended operation in an aircraft environment. The GASP system is described along with analyzer operation, calibration procedures, and measurement errors. Uncertainty of the CO measurement over a 2-year period ranged from + or - 3 to + or - 13 percent of reading, plus an error due to random fluctuation of the output signal + or - 3 to + or - 15 ppbv.

Dudzinski, T. J.

1979-01-01

215

Carbon monoxide expedites metabolic exhaustion to inhibit tumor growth.  

PubMed

One classical feature of cancer cells is their metabolic acquisition of a highly glycolytic phenotype. Carbon monoxide (CO), one of the products of the cytoprotective molecule heme oxygenase-1 (HO-1) in cancer cells, has been implicated in carcinogenesis and therapeutic resistance. However, the functional contributions of CO and HO-1 to these processes are poorly defined. In human prostate cancers, we found that HO-1 was nuclear localized in malignant cells, with low enzymatic activity in moderately differentiated tumors correlating with relatively worse clinical outcomes. Exposure to CO sensitized prostate cancer cells but not normal cells to chemotherapy, with growth arrest and apoptosis induced in vivo in part through mitotic catastrophe. CO targeted mitochondria activity in cancer cells as evidenced by higher oxygen consumption, free radical generation, and mitochondrial collapse. Collectively, our findings indicated that CO transiently induces an anti-Warburg effect by rapidly fueling cancer cell bioenergetics, ultimately resulting in metabolic exhaustion. PMID:24121491

Wegiel, Barbara; Gallo, David; Csizmadia, Eva; Harris, Clair; Belcher, John; Vercellotti, Gregory M; Penacho, Nuno; Seth, Pankaj; Sukhatme, Vikas; Ahmed, Asif; Pandolfi, Pier Paolo; Helczynski, Leszek; Bjartell, Anders; Persson, Jenny Liao; Otterbein, Leo E

2013-12-01

216

Carbon monoxide poisoning in narghile (water pipe) tobacco smokers.  

PubMed

Narghile (water pipe, hookah, shisha, goza, hubble bubble, argeela) is a traditional method of tobacco use. In recent years, its use has increased worldwide, especially among young people. Narghile smoking, compared to cigarette smoking, can result in more smoke exposure and greater levels of carbon monoxide (CO). We present an acutely confused adolescent patient who had CO poisoning after narghile tobacco smoking. She presented with syncope and a carboxyhemoglobin level of 24% and was treated with hyperbaric oxygen. Five additional cases of CO poisoning after narghile smoking were identified during a literature search, with carboxyhemoglobin levels of 20 to 30%. Each patient was treated with oxygen supplementation and did well clinically. In light of the increasing popularity of narghile smoking, young patients presenting with unexplained confusion or nonspecific neurologic symptoms should be asked specifically about this exposure, followed by carboxyhemoglobin measurement. PMID:22417961

La Fauci, Giovanna; Weiser, Giora; Steiner, Ivan P; Shavit, Itai

2012-01-01

217

Effect of carbon monoxide on Mycobacterium tuberculosis pathogenesis  

PubMed Central

The intracellular pathogen Mycobacterium tuberculosis (Mtb) is exposed to multiple host antimicrobial pathways, including toxic gases such as superoxide, nitric oxide and carbon monoxide (CO). To survive, mycobacteria evolved mechanisms to resist the toxic environment, and in this review we focus on a relatively new field, namely, the role of macrophage heme oxygenase and its enzymatic product CO in Mtb pathogenesis. In particular, we focus on (i) the induction of heme oxygenase during Mtb infection and its relevance to Mtb pathogenesis, (ii) the ability of mycobacteria to catabolize CO, (iii) the transcriptional reprogramming of Mtb by exposure to CO, (iv) the general antimicrobial properties of CO and (v) new genetic evidence characterizing the ability of Mtb to resist CO toxicity. Developing a complete molecular and genetic understanding of the pathogenesis of Mtb is essential to its eventual eradication.

2012-01-01

218

The Social Network of Carbon Monoxide in Medicine  

PubMed Central

Networking between cells is critical for proper functioning of the cellular milieu and is mediated by cascades of highly regulated and overlapping signaling molecules. The enzyme heme oxygenase-1 (HO-1) generates three separate signaling molecules through the catalysis of heme – carbon monoxide (CO), biliverdin, and iron – each of which acts via distinct molecular targets to influence cell function, both proximally and distally. This review focuses on state-of-the art developments and insights into the impact of HO-1 and CO on the innate immune response, the effects of which are responsible for an ensemble of functions that help regulate complex immunologic responses to bacterial sepsis and ischemia/reperfusion injury. HO-1 exemplifies an evolutionarily conserved system necessary for the cellular milieu to adapt appropriately, function properly, and ensure survival of the organism.

Wegiel, Barbara; Hanto, Douglas W.; Otterbein, Leo E.

2012-01-01

219

Regulation of ROS Production and Vascular Function by Carbon Monoxide  

PubMed Central

Carbon monoxide (CO) is a gaseous molecule produced from heme by heme oxygenase (HO). CO interacts with reduced iron of heme-containing proteins, leading to its involvement in various cellular events via its production of mitochondrial reactive oxygen species (ROS). CO-mediated ROS production initiates intracellular signal events, which regulate the expression of adaptive genes implicated in oxidative stress and functions as signaling molecule for promoting vascular functions, including angiogenesis and mitochondrial biogenesis. Therefore, CO generated either by exogenous delivery or by HO activity can be fundamentally involved in regulating mitochondria-mediated redox cascades for adaptive gene expression and improving blood circulation (i.e., O2 delivery) via neovascularization, leading to the regulation of mitochondrial energy metabolism. This paper will highlight the biological effects of CO on ROS generation and cellular redox changes involved in mitochondrial metabolism and angiogenesis. Moreover, cellular mechanisms by which CO is exploited for disease prevention and therapeutic applications will also be discussed.

Choi, Yoon Kyung; Por, Elaine D.; Kwon, Young-Guen; Kim, Young-Myeong

2012-01-01

220

Concentration of carbon monoxide in the upper stratosphere  

NASA Technical Reports Server (NTRS)

The concentration of telluric carbon monoxide has been determined in the upper stratosphere from infrared solar spectra recorded by balloon in October 1978 and September 1979, over Texas. The average mixing ratios were found to be (2.1 plus or minus 3) x 10 to the -8th ppv and (3.7 plus or minus 0.4) x 10 the the -8th ppv above the float altitudes of 30.6 and 36.8 km, respectively. The concentration profile deduced from all the measurements indicates that the CO mixing ratio increases in the upper stratosphere, from (1 plus or minus 0.3) x 10 to the -8th ppv at 30.6 km, to about 4 x 10 to the -8th ppv above 41 km.

Zander, R.; Leclercq, H.; Kaplan, L. D.

1981-01-01

221

Carbon monoxide--physiology, detection and controlled release.  

PubMed

Carbon monoxide (CO) is increasingly recognized as a cell-signalling molecule akin to nitric oxide (NO). CO has attracted particular attention as a potential therapeutic agent because of its reported anti-hypertensive, anti-inflammatory and cell-protective effects. We discuss recent progress in identifying new effector systems and elucidating the mechanisms of action of CO on, e.g., ion channels, as well as the design of novel methods to monitor CO in cellular environments. We also report on recent developments in the area of CO-releasing molecules (CORMs) and materials for controlled CO application. Novel triggers for CO release, metal carbonyls and degradation mechanisms of CORMs are highlighted. In addition, potential formulations of CORMs for targeted CO release are discussed. PMID:24556640

Heinemann, Stefan H; Hoshi, Toshinori; Westerhausen, Matthias; Schiller, Alexander

2014-04-11

222

The social network of carbon monoxide in medicine.  

PubMed

Networking between cells is critical for proper functioning of the cellular milieu and is mediated by cascades of highly regulated and overlapping signaling molecules. The enzyme heme oxygenase-1 (HO-1) generates three separate signaling molecules through the catalysis of heme - carbon monoxide (CO), biliverdin, and iron - each of which acts via distinct molecular targets to influence cell function, both proximally and distally. This review focuses on state-of-the art developments and insights into the impact of HO-1 and CO on the innate immune response, the effects of which are responsible for an ensemble of functions that help regulate complex immunological responses to bacterial sepsis and ischemia/reperfusion injury. HO-1 exemplifies an evolutionarily conserved system necessary for the cellular milieu to adapt appropriately, function properly, and ensure survival of the organism. PMID:23140858

Wegiel, Barbara; Hanto, Douglas W; Otterbein, Leo E

2013-01-01

223

Soft fragmentation of carbon monoxide by slow highly charged ions  

NASA Astrophysics Data System (ADS)

The fragmentation pattern and corresponding kinetic energy release distributions from carbon monoxide after collisions with slow, highly charged ions ( C6+ at v=0.8a.u. and Ar11+ at v=0.39a.u. ) are reported. Correlated measurements of the projectile final charge state and all charged molecular fragments were obtained using a coincidence time-of-flight technique coupled to projectile charge state separation. Fragmentation branching ratios for the dominant electron capture processes in these collisions are similar to those resulting from ionization by fast highly charged projectiles. This result can help simplify simulations of astrophysical or artificial plasma environments, as the branching ratio may be considered essentially constant for both electron capture and ionization as long as the relevant impact parameter is large.

Wells, E.; Nishide, T.; Tawara, H.; Watson, R. L.; Carnes, K. D.; Ben-Itzhak, I.

2008-06-01

224

Neuroprotective effects of erythropoietin in patients with carbon monoxide poisoning.  

PubMed

The purpose of this study was to evaluate the efficacy of erythropoietin (EPO) for treating patients with carbon monoxide (CO) poisoning. We conducted a randomized, prospective study of 103 patients with CO poisoning in two groups: an EPO group (n = 54; patients received EPO) and a placebo group (n = 49; patients received normal saline). The study endpoints were the functional outcome at day 30 (the Barthel index and neurologic sequelae), National Institutes of Health Stroke Scale (NIHSS) score, and the levels of S-100?. At 18 days, the NIHSS score improved significantly and S-100? levels significantly decreased in patients in the EPO group. At 30 days, patients in the EPO group had a superior Barthel index and fewer patients had delayed neurologic sequelae (DNS). This study demonstrated that early administration of EPO to patients with CO poisoning improved neurological outcomes and reduced the incidence of DNS. PMID:23554277

Pang, Li; Bian, Miao; Zang, Xiu-Xian; Wu, Yang; Xu, Da-Hai; Dong, Ning; Wang, Zhi-Hao; Yan, Bai-Ling; Wang, Da-Wei; Zhao, Hui-Jie; Zhang, Nan

2013-05-01

225

Prevention of carbon monoxide exposure in general and recreational aviation.  

PubMed

Carbon monoxide exposure is an important public health issue that poses a significant, albeit uncommon risk in aviation. Exposure is most common in single engine piston-driven aircraft where air is passed over the exhaust manifold to serve as cabin heat. Effective primary prevention of this exposure is the regular inspection and maintenance of aircraft exhaust systems, as required by law. For situations at special risk should exposure occur, and where there is concern for the public safety, installation of active warning devices for CO intrusion into cockpits may improve secondary prevention. Modern studies should be performed of occupation-specific abilities to support the 50 ppm FAA CO exposure standard and 50-70 ppm FAA Technical Standard Order (TSO) for CO monitors alerting pilots to the possibility of exhaust gas intrusion into their cockpits. PMID:12182223

Zelnick, Sanford D; Lischak, Michael W; Young, David G; Massa, Thomas V

2002-08-01

226

AANA journal course: update for nurse anesthetists--carbon monoxide poisoning: role of the anesthesia machine's carbon dioxide absorption system.  

PubMed

Carbon monoxide is a colorless, odorless, and tasteless gas that, when inhaled, is toxic to humans. In 1965, Middleton reported the detection of carbon monoxide in the closed anesthetic circuits of patients undergoing surgery. In recent years, anesthesia providers from at least four American hospitals have reported instances of intraoperative carbon monoxide poisoning in anesthetized patients undergoing surgery. Although no deaths were associated with these incidents, carboxyhemoglobin levels ranged from 8.5% to 32%. In virtually all reported cases, the incidents occurred in surgical suites that had not been used for at least 2 days. This facet of the phenomenon advanced the theory that a slow chemical reaction, probably involving soda lime or barium hydroxide lime, was responsible for the liberation of carbon monoxide within the anesthesia circuit. Recent research has attributed this generation of carbon monoxide to the degradation of volatile anesthetic agents by desiccated carbon dioxide absorbents. Although carbon monoxide poisoning of patients undergoing anesthesia with volatile anesthetics is probably a rare occurrence, it is a potential problem for all anesthesia providers. PMID:8928599

Altman, C

1996-02-01

227

Evidence for Horizontal Gene Transfer of Anaerobic Carbon Monoxide Dehydrogenases  

PubMed Central

Carbon monoxide (CO) is commonly known as a toxic gas, yet both cultivation studies and emerging genome sequences of bacteria and archaea establish that CO is a widely utilized microbial growth substrate. In this study, we determined the prevalence of anaerobic carbon monoxide dehydrogenases ([Ni,Fe]-CODHs) in currently available genomic sequence databases. Currently, 185 out of 2887, or 6% of sequenced bacterial and archaeal genomes possess at least one gene encoding [Ni,Fe]-CODH, the key enzyme for anaerobic CO utilization. Many genomes encode multiple copies of [Ni,Fe]-CODH genes whose functions and regulation are correlated with their associated gene clusters. The phylogenetic analysis of this extended protein family revealed six distinct clades; many clades consisted of [Ni,Fe]-CODHs that were encoded by microbes from disparate phylogenetic lineages, based on 16S rRNA sequences, and widely ranging physiology. To more clearly define if the branching patterns observed in the [Ni,Fe]-CODH trees are due to functional conservation vs. evolutionary lineage, the genomic context of the [Ni,Fe]-CODH gene clusters was examined, and superimposed on the phylogenetic trees. On the whole, there was a correlation between genomic contexts and the tree topology, but several functionally similar [Ni,Fe]-CODHs were found in different clades. In addition, some distantly related organisms have similar [Ni,Fe]-CODH genes. Thermosinus carboxydivorans was used to observe horizontal gene transfer (HGT) of [Ni,Fe]-CODH gene clusters by applying Kullback–Leibler divergence analysis methods. Divergent tetranucleotide frequency and codon usage showed that the gene cluster of T. carboxydivorans that encodes a [Ni,Fe]-CODH and an energy-converting hydrogenase is dissimilar to its whole genome but is similar to the genome of the phylogenetically distant Firmicute, Carboxydothermus hydrogenoformans. These results imply that T carboxydivorans acquired this gene cluster via HGT from a relative of C. hydrogenoformans.

Techtmann, Stephen M.; Lebedinsky, Alexander V.; Colman, Albert S.; Sokolova, Tatyana G.; Woyke, Tanja; Goodwin, Lynne; Robb, Frank T.

2012-01-01

228

Carbochlorination kinetics of titanium dioxide with carbon and carbon monoxide as reductant  

NASA Astrophysics Data System (ADS)

Kinetic study of the chlorination of titanium dioxide (rutile and anatase) was carried out in a fixedbed reactor at temperature ranging from 800 °C to 1000 °C and normal pressure. In our experiment, titanium dioxide powder and gaseous chlorine with carbon or carbon monoxide as reductant were used. The products of the reaction are all in gaseous phase under the temperatures and pressure studied. With CO as reductant, reaction is of noncatalytic gas-solid nature and experimental data fit the shrinking core model. When using C as reductant, solid-solid reaction is involved. Reactivity is highly enhanced by solid carbon and it is concluded that an activated C-TiO2-Cl complex contributes to the enhanced reactivity. A reaction model based on phase boundary control applies to the experimental data. Thermodynamic analysis supports the experimental observation.

Yang, Fenglin; Hlavacek, Vladimir

1998-12-01

229

COSMIC: Carbon Monoxide and Soot in Microgravity Inverse Combustion  

NASA Technical Reports Server (NTRS)

Almost seventy percent of deaths in accidental fires are caused by inhalation of toxins such as carbon monoxide (CO) and smoke (soot) that form during underventilated burning. The COSMIC project examines the formation mechanisms of CO and soot during underventilated combustion, achieved presently using laminar, inverse diffusion flames (IDFs) formed between an air jet and surrounding fuel. A major hypothesis of the project is that the IDF mimics underventilated combustion because carbon-containing species that form on the fuel side of the flame (such as CO and soot) can escape without passing through an oxidizing flame tip. An IDF literature review was presented at the last microgravity workshop, and a few additional IDF papers have appeared since that meeting. The COSMIC project is entering the third year of its four-year funding cycle. The first two years have been devoted to designing and constructing a rig for use in the NASA 2.2-second drop tower. A few computations and laboratory experiments have been performed. The goals of this paper are to discuss the use of numerical simulation during burner design, to present computational and experimental results that support the hypothesis that IDFs are similar to underventilated flames, and to delineate future plans.

Blevins, L. G.; Fernandez, M. G.; Mulholland, G. W.; Davis, R. W.; Moore, E. F.; Steel, E. B.; Scott, J. H. J.

2001-01-01

230

The combined effect of noise and carbon monoxide on hearing thresholds of exposed workers  

NASA Astrophysics Data System (ADS)

Animal models have been used to demonstrate the potentiation of noise-induced hearing loss (NIHL) by carbon monoxide. It has been shown that the addition of carbon monoxide to otherwise safe noise exposure levels produces significant NIHL in rats. However, the effects of chronic exposure to low level of carbon monoxide in a noisy work environment are still unknown. The aim of this study was to compare the hearing thresholds of a group of workers exposed to noise and carbon monoxide (Group 1) to another group of workers where carbon monoxide exposure is absent or negligible (Group 2). The analysis was based on 9396 audiograms collected by the Quebec National Public Health Institute between 1983 and 1996. The results show significantly poorer hearing thresholds at high frequencies (3, 4, and 6 kHz) for the carbon monoxide exposed group (p<0.001). The potentiation effect also varied according to years of exposure in work place; a larger effect is observed for workers with between 15 to 20 years of exposure (p<0.001). This study provides the first demonstration of a potentiation effect of NIHL by carbon monoxide in humans.

Lacerda, Adriana; Leroux, Tony; Gagn, Jean-Pierre

2005-04-01

231

Estimating Effects of Brazilian Forest Wildfires on the Carbon Monoxide Concentration  

NASA Astrophysics Data System (ADS)

Forest wildfires have dramatically increased in recent years due to global warming and extreme dry conditions. Forest wildfires spew out a significant amount of atmospheric pollutants, such as carbon monoxide, due to incomplete burning of the biomass. According to United State Environmental Protection Agency (EPA), a high increase of carbon monoxide leads to the formation of carboxyhemoglobin in blood which decreases the oxygen intake capacity of human body and at moderate concentration angina, impaired vision and reduced brain function may occur. As compared to Northern America where significant amount of carbon monoxide released is caused by combustion devices and furnace, the increase of carbon monoxide concentration in Brazilian regions is mainly attributed to the forest fires. In this study, carbon monoxide datasets from the Measurements of pollution in the troposphere (MOPITT) have been analyzed to see the amount of increase in the carbon monoxide concentration after forest wildfires, ire, particularly in summer of 2003. The study reveals that there is a significant increase in the carbon monoxide concentration after forest fires.

Bhoi, S.; Qu, J.; Dasgupta, S.

2004-12-01

232

Autumn photoproduction of carbon monoxide in Jiaozhou Bay, China  

NASA Astrophysics Data System (ADS)

Carbon monoxide (CO) plays a significant role in global warming and atmospheric chemistry. Global oceans are net natural sources of atmospheric CO. CO at surface ocean is primarily produced from the photochemical degradation of chromophoric dissolved organic matter (CDOM). In this study, the effects of photobleaching, temperature and the origin (terrestrial or marine) of CDOM on the apparent quantum yields (AQY) of CO were studied for seawater samples collected from Jiaozhou Bay. Our results demonstrat that photobleaching, temperature and the origin of CDOM strongly affected the efficiency of CO photoproduction. The concentration, absorbance and fluorescence of CDOM exponentially decreased with increasing light dose. Terrestrial riverine organic matter could be more prone to photodegradation than the marine algae-derived one. The relationships between CO AQY and the dissolved organic carbon-specific absorption coefficient at 254 nm for the photobleaching study were nonlinear, whereas those of the original samples were strongly linear. This suggests that: 1) terrestrial riverine CDOM was more efficient than marine algae-derived CDOM for CO photoproduction; 2) aromatic and olefinic moieties of the CDOM pool were affected more strongly by degradation processes than by aliphatic ones. Water temperature and the origin of CDOM strongly affected the efficiency of CO photoproduction. The photoproduction rate of CO in autumn was estimated to be 31.98 ?mol m-2 d-1 and the total DOC photomineralization was equivalent to 3.25%-6.35% of primary production in Jiaozhou Bay. Our results indicate that CO photochemistry in coastal areas is important for oceanic carbon cycle.

Ren, Chunyan; Yang, Guipeng; Lu, Xiaolan

2014-06-01

233

Suppression of carbon monoxide formation in oxide-coated TZM molybdenum X-ray rotating anodes  

Microsoft Academic Search

Higher performance designs for rotating anode X-ray tubes have increased the average rotating anode temperature from below 1100 °C to well above 1300 °C. This temperature increase has accelerated the formation of carbon monoxide by reaction of carbon from the alloy substrate with oxygen from the emissive coating. The dominant carbon source is thought to be Mo2C grain boundary precipitates

T. C. Tiearney

1995-01-01

234

Regional studies of potential carbon monoxide sources based on Space Shuttle and aircraft measurements  

NASA Technical Reports Server (NTRS)

Carbon monoxide measurements made from the Space Shuttle show maxima over South America, central Africa, the eastern Mediterranean, and China. The maxima appear to be associated with either concomitant or prior convection in the air masses which carries boundary layer air into the upper troposphere. Previous aircraft measurements of carbon monoxide and ozone over South America are shown to be consistent with this view. In the tropics the three regions of long-term mean rising motion, which form part of the Walker circulation, are associated with elevated carbon monoxide.

Newell, R. E.; Shipley, S. T.; Connors, V. S.; Reichle, H. G., Jr.

1988-01-01

235

Regional studies of potential carbon monoxide sources based on Space Shuttle and aircraft measurements  

NASA Technical Reports Server (NTRS)

Carbon monoxide measurements made from the space shuttle show maxima over South America, central Africa, the eastern Mediterranean, and China. The maxima appear to be associated with either concomitant or prior convection in the air masses which carries boundary layer air into the upper troposphere. Previous aircraft measurements of carbon monoxide and ozone over South America are shown to be consistent with this view. In the tropics the three regions of long-term mean rising motion, which form part of the Walker circulation, are associated with elevated carbon monoxide.

Newell, R. E.; Shipley, S. T.; Connors, V. S.; Reichle, H. G., Jr.

1988-01-01

236

Increased carbon monoxide production by hemeoxygenase-1 caused by device-mediated hemolysis: thrombotic phantom menace?  

PubMed

Replacement of key components of the circulatory system with artificial devices has become the mainstay of therapy for conditions such as end-stage valvular disease or congestive heart failure. Unfortunately, device thrombosis and thromboembolic morbidity persist despite optimized anticoagulation. This work reviews the commonly known causes of device-associated thrombophilia, introduces recent literature concerning the effect of carbon monoxide on coagulation, and presents new patient data linking endogenously produced carbon monoxide with device-associated thrombosis. A new paradigm involving the interaction of red blood cell lysis-induced upregulation of hemoxygenase-1, increased endogenous carbon monoxide, hyperfibrinogenemia, and contact protein/microparticle-induced thrombin generation is presented. PMID:23865494

Nielsen, Vance G; Pearson, Ellen C; Smith, M Cristina

2013-11-01

237

Diagnosing black carbon trends in large urban areas using carbon monoxide measurements  

NASA Astrophysics Data System (ADS)

The relationship between black carbon (BC) and carbon monoxide (CO) has been analyzed using measurements from two sites in Mexico City and five urban areas in Germany. The correlation coefficient between BC and CO is greater than 0.90 for all sites. The average slope of the linear regression line for BC versus CO is 2.2 ?g mg-1 for German sites and 1.1 ?g mg-1 in Mexico City. The most important factors that affect the BC to CO relationship appear to be the ratio of diesel to gasoline usage and the combustion efficiency of vehicles in a particular area. The results of this analysis suggest that CO measurements in urban areas can be used to estimate BC mass when direct measurements are not available.

Baumgardner, Darrel; Raga, G.; Peralta, O.; Rosas, I.; Castro, T.; Kuhlbusch, T.; John, A.; Petzold, A.

2002-11-01

238

Gold Nanoparticles Supported on Carbon Nitride: Influence of Surface Hydroxyls on Low Temperature Carbon Monoxide Oxidation  

SciTech Connect

This paper reports the synthesis of 2.5 nm gold clusters on the oxygen free and chemically labile support carbon nitride (C3N4). Despite having small particle sizes and high enough water partial pressure these Au/C3N4 catalysts are inactive for the gas phase and liquid phase oxidation of carbon monoxide. The reason for the lack of activity is attributed to the lack of surface OH groups on the C3N4. These OH groups are argued to be responsible for the activation of CO in the oxidation of CO. The importance of basic OH groups explains the well document dependence of support isoelectric point versus catalytic activity.

Singh, Joseph A [ORNL; Dudney, Nancy J [ORNL; Li, Meijun [ORNL; Overbury, Steven {Steve} H [ORNL; Veith, Gabriel M [ORNL

2012-01-01

239

Influence of Oxygen and Carbon Monoxide Concentrations on Blood Carboxyhemoglobin Saturation.  

National Technical Information Service (NTIS)

Blood carboxyhemoglobin has been measured in man and related to existing concentrations of oxygen and carbon monoxide in inspired air. An equation is presented to estimate the quilibrium COHb levels when the inspired air composition is known. A subject on...

F. L. Rodkey H. A. Collison J. D. O'Neal

1971-01-01

240

Residential Carbon Monoxide Exposure due to Indoor Generator Operation: Effects of Source Location and Emission Rate.  

National Technical Information Service (NTIS)

The U.S. Consumer Product Safety Commission (CPSC) and others are concerned about the hazard of acute residential carbon monoxide (CO) exposures from portable gasoline powered generators that can result in death or serious adverse health effects in expose...

A. K. Persily B. Polidoro S. J. Emmerich Y. Wang

2013-01-01

241

Production of carbon monoxide-free hydrogen and helium from a high-purity source  

DOEpatents

The invention provides vacuum swing adsorption processes that produce an essentially carbon monoxide-free hydrogen or helium gas stream from, respectively, a high-purity (e.g., pipeline grade) hydrogen or helium gas stream using one or two adsorber beds. By using physical adsorbents with high heats of nitrogen adsorption, intermediate heats of carbon monoxide adsorption, and low heats of hydrogen and helium adsorption, and by using vacuum purging and high feed stream pressures (e.g., pressures of as high as around 1,000 bar), pipeline grade hydrogen or helium can purified to produce essentially carbon monoxide -free hydrogen and helium, or carbon monoxide, nitrogen, and methane-free hydrogen and helium.

Golden, Timothy Christopher (Allentown, PA); Farris, Thomas Stephen (Bethlehem, PA)

2008-11-18

242

77 FR 8252 - Adequacy Status of the Anchorage, Alaska, Carbon Monoxide Maintenance Plan for Transportation...  

Federal Register 2010, 2011, 2012, 2013

...in the Anchorage, Alaska, Carbon Monoxide (CO...Plan, submitted by the State of Alaska on September 20, 2011...submitted during the State hearing process regarding...sent a letter to the Alaska Department of...

2012-02-14

243

78 FR 48638 - Approval and Promulgation of State Implementation Plans: Alaska; Fairbanks Carbon Monoxide...  

Federal Register 2010, 2011, 2012, 2013

...FRL-9844-7] Approval and Promulgation of State Implementation Plans: Alaska; Fairbanks Carbon Monoxide Limited Maintenance...Transportation Control Program, submitted by the State of Alaska as a revision to its State Implementation Plan dated April 22,...

2013-08-09

244

Carbon Monoxide Production in Response to Increased Reforestation and Traffic in Eastern United States.  

National Technical Information Service (NTIS)

This report presents results from field and theoretical studies designed to evaluate the central research hypothesis that increases in forests and vehicle inventories will augment carbon monoxide levels in eastern United States. In support of this hypothe...

J. D. Fuentes M. Demetsky

2003-01-01

245

Death scene evaluation in a case of fatal accidental carbon monoxide toxicity.  

PubMed

Exposure of humans to high concentrations of carbon monoxide can result in death, due to the formation of carboxyhaemoglobin (COHb), which impairs the oxygen carrying capacity of the haemoglobin. Carbon monoxide is responsible of a great number of accidental domestic poisonings and deaths throughout the world, particularly in homes that have faulty or poorly vented combustion appliances. A case is reported, in which a 21-year-old woman was found dead, due to carbon monoxide poisoning from a gas water heater, despite the puzzling evidence that the heater has been used for more than 10 years without any problem. An evaluation of the exposure to CO was performed, by measuiring the rate of production of CO from the heater, and using the Coburn-Forster-Kane equation to describe the kinetics of the poisoning process. The death was attributed to an accidental poisoning from carbon monoxide due to a sum of unfortunate circumstances. PMID:16439085

Sedda, Antioco Franco; Rossi, Gabriele

2006-12-20

246

Analysis of the Feasibility of an Experiment to Measure Carbon Monoxide in the Atmosphere.  

National Technical Information Service (NTIS)

The feasibility of measuring atmospheric carbon monoxide from a remote platform using the correlation interferometry technique was considered. It has been determined that CO data can be obtained with an accuracy of 10 percent using this technique on the f...

F. N. Alyea G. M. Levy G. R. Liebling M. H. Bortner R. N. Grenda

1973-01-01

247

FIELD SURVEYS OF CARBON MONOXIDE IN COMMERCIAL SETTINGS USING PERSONAL EXPOSURE MONITORS  

EPA Science Inventory

This study employed miniaturized personal exposure monitors (PEMs) to measure carbon monoxide (CO) in 588 different commercial settings (e.g., retail stores, office buildings, hotels, restaurants) in five California cities. Altogether, 5000 CO observations were made by recording ...

248

Molten metal reactor and method of forming hydrogen, carbon monoxide and carbon dioxide using the molten alkaline metal reactor  

DOEpatents

A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbon dioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

Bingham, Dennis N.; Klingler, Kerry M.; Turner, Terry D.; Wilding, Bruce M.

2012-11-13

249

Resonantly enhanced vacuum-ultraviolet generation and multiphoton ionization in carbon monoxide gas  

SciTech Connect

Competition between three-photon resonantly enhanced vacuum ultraviolet third-harmonic generation and six-photon multiphoton ionization using the A state in gaseous carbon monoxide is observed. Excitation spectra of the third-harmonic emission exhibit increasing blue shifts and broadening with increasing pressure due to the phase matching requirements. Estimates for the efficiency and tunability show that third-harmonic generation in carbon monoxide molecules is a promising source for coherent vacuum ultraviolet light.

Glownia, J.H.; Sander, R.K.

1982-01-01

250

Carbon monoxide sensors. (Latest citations from the EI Compendex*plus database). Published Search  

SciTech Connect

The bibliography contains citations concerning the design, manufacture, and evaluation of carbon monoxide sensors. Citations discuss chemical and electrochemical sensors, sensor response, sensor materials, and carbon monoxide measurements in flow and flame environments. Emission monitoring and identification systems, and portable emission analyzers are presented. Applications in automobile emission analysis and control, reactor control, and alarm systems are examined. (Contains a minimum of 191 citations and includes a subject term index and title list.)

NONE

1995-05-01

251

Digital image analysis of fingernail colour in cadavers comparing carbon monoxide poisoning to controls  

Microsoft Academic Search

Carbon monoxide is a component of motor vehicle exhaust fumes, provided a functional catalytic converter is not present. This\\u000a gas binds avidly to the hemoglobin molecule in red blood cells preventing its oxygen transport function, effectively poisoning\\u000a the body by starving it of oxygen. In binding to hemoglobin, carbon monoxide forms carboxyhemoglobin, which has a characteristic\\u000a bright pink color. It

Neil E. I. Langlois

2010-01-01

252

Myocardial findings in fatal carbon monoxide poisoning: a human and experimental morphometric study  

Microsoft Academic Search

The aim of this study was to define the status of the myocardium in selected human cases of acute, fatal carbon monoxide\\u000a intoxication and the myocardial changes in rats exposed to carbon monoxide in relation to the type of cardiac arrest and the\\u000a effects of reoxygenation following pre-fatal CO intoxication. The human study consisted of 26 cases (17 accidental and

Vittorio Fineschi; Eustachio Agricola; Giorgio Baroldi; Giancarlo Bruni; Daniela Cerretani; Sergio Mondillo; Marina Parolini; Emanuela Turillazzi

2000-01-01

253

Study of carbon monoxide distribution determinations for a global transport model. Final report  

SciTech Connect

The primary objective of this grant was to further the development of a global transport/chemistry model that simulates the physico-chemical behavior of methane and carbon monoxide in the troposphere. The computer simulation model is designed to analyze the processes that occur as methane and carbon monoxide are transported from their respective sources to their ultimate fate, e.g., final conversion to CO/sub 2/, transport to the stratosphere, deposition at ground level, etc.

Peters, L.K.

1988-12-01

254

A study of carbon monoxide distribution determinations for a global transport model  

NASA Technical Reports Server (NTRS)

The primary objective of this grant was to further the development of a global transport/chemistry model that simulates the physico-chemical behavior of methane and carbon monoxide in the troposphere. The computer simulation model is designed to analyze the processes that occur as methane and carbon monoxide are transported from their respective sources to their ultimate fate, e.g., final conversion to CO2, transport to the stratosphere, deposition at ground level, etc.

Peters, Leonard K.

1988-01-01

255

Mild carbon monoxide poisoning impairs left ventricular diastolic function  

PubMed Central

Rationale: Carbon monoxide (CO) poisoning is associated with direct cardiovascular toxicity. In mild CO poisoning in which cardiovascular life support is not required, the effects of CO on left and right ventricular functions are unknown in patients without cardiac failure. Objectives: Echocardiography was used to determine whether or not mild CO poisoning impairs ventricular function. Twenty otherwise healthy patients with CO poisoning and 20 age- and gender-matched controls were studied. Echocardiographic examinations were performed at the time of admission and 1 week after poisoning. Results: The impairment observed in the left and right ventricular diastolic function at the time of admission was greater than the impairment 1 week after poisoning. Mild CO poisoning did not have a significant effect on systolic function. Carboxyhemoglobin levels were positively correlated with left ventricular diastolic dysfunction, whereas the levels were not correlated with right ventricular diastolic function. Conclusions: In CO intoxication, the development of left and right ventricular diastolic dysfunction precedes systolic abnormality. Patients with mild CO poisoning do not manifest cardiovascular symptoms; however, it should be borne in mind that most of these patients have myocardial involvement.

Ciftci, Ozgur; Gunday, Murat; Cal?skan, Mustafa; Gullu, Hakan; Dogan, Rafi; Guven, Aytekin; Muderrisoglu, Haldun

2013-01-01

256

Multilayer Adsorption of Neon, Hydrogens, and Carbon Monoxide on Graphite.  

NASA Astrophysics Data System (ADS)

Multilayer adsorption of neon, hydrogens (H _2, HD, and D_2), and carbon monoxide on graphite have been investigated using ellipsometric-coverage vapor-pressure isotherm measurements. Chemical potentials at layer condensations and widths of the layer condensation steps were tabulated, and layer critical points were determined from the temperature dependence of the widths for all five adsorbates. In Ne we do not find evidence for reentrant first -order layering, which was previously found in Ar, Kr, and Xe. The adsorption behavior on graphite of H_2, HD, and D_2 is very similar. We observed temperature-dependent splitting and hysteresis in the fourth, fifth, and sixth layers in all three adsorbates. This may suggest structure changes, possibly between face-centered cubic and hexagonal closed-packed stacking, in these layers. In CO, below the bulk alpha- beta transition temperature, we have seen incomplete wetting with a series of layer-appearance transitions from the third to the tenth layer. Above the alpha-beta transition temperature, the thickness of the film remains around 11 layers. We observed reentrant first-order layering in the condensation of the fourth layer in CO. But the broadening feature is much weaker compared to Ar, Kr, and Xe, and is not observed at all in the higher layers.

Wu, Hong

257

[Subclinical carbon monoxide poisoning in our health area].  

PubMed

We present an observation study on the relatioship between high levels of carboxyhemoglobin (COHB) and subclinical poisoning by carbon monoxide (CO) in our health area. The study was carried out in February and March 2000 in 228 over 18-year-old patients of both sexes who went to the Emergency Room for various reasons. After an informed consent was conceded, a venous blood sample was obtained in order to determine the level of COHB; later, we collected the anthropometric data, the data relative to the tobacco use, and the data of the type of heating at home. The values limit of the COHB obtained were the following: in non smokers, 1.9%; in 1-10 cigarettes/day smokers, 5.2%; in 11-20 cigarettes/day smokers, 6.9%; in >20 cigarettes/day smokers, 9.6%. A COHB high level was observed in 25% of the patients regardless of the smoking habits, being the coal-dust slack brazier the source of most frequent exposure to CO. PMID:12855117

García Arroyo, I; Fernández Testa, A; Ochoa Sangrador, C; Antolín García, M T; Sánchez Berrocal, J L; Ramos Pastor, N; Montero Martín, J; San Norberto García, L; Fernández García, M C; Gutiérrez Maire-Richard, E

2003-08-01

258

Carbon monoxide: present and future indications for a medical gas.  

PubMed

Gaseous molecules continue to hold new promise in molecular medicine as experimental and clinical therapeutics. The low molecular weight gas carbon monoxide (CO), and similar gaseous molecules (e.g., H2S, nitric oxide) have been implicated as potential inhalation therapies in inflammatory diseases. At high concentration, CO represents a toxic inhalation hazard, and is a common component of air pollution. CO is also produced endogenously as a product of heme degradation catalyzed by heme oxygenase enzymes. CO binds avidly to hemoglobin, causing hypoxemia and decreased oxygen delivery to tissues at high concentrations. At physiological concentrations, CO may have endogenous roles as a signal transduction molecule in the regulation of neural and vascular function and cellular homeostasis. CO has been demonstrated to act as an effective anti-inflammatory agent in preclinical animal models of inflammation, acute lung injury, sepsis, ischemia/reperfusion injury, and organ transplantation. Additional experimental indications for this gas include pulmonary fibrosis, pulmonary hypertension, metabolic diseases, and preeclampsia. The development of chemical CO releasing compounds constitutes a novel pharmaceutical approach to CO delivery with demonstrated effectiveness in sepsis models. Current and pending clinical evaluation will determine the usefulness of this gas as a therapeutic in human disease. PMID:23525151

Ryter, Stefan W; Choi, Augustine M K

2013-03-01

259

Nitric Oxide and Carbon Monoxide Production and Metabolism in Preeclampsia  

PubMed Central

Objective: To elucidate the regulation of the nitric oxide (NO) and carbon monoxide (CO) pathways in preeclampsia and to evaluate the ratio of asymmetric dimethylarginine (ADMA) to symmetric dimethylarginine (SDMA) as a marker for preeclampsia. Methods: Maternal plasma and placental samples were obtained from 20 participants with preeclampsia and 23 controls. Enzyme-linked immunosorbent assay was used to measure plasma NO, ADMA, and SDMA as well as placental NO and hemeoxygnase 1 (HO-1). Western blot was used to measure placental dimethylarginine dimethylaminotransferases (DDAH-I and DDAH-II). Results: Placental DDAH-I, placental DDAH-II, placental NO, and placental HO-1 were significantly decreased in participants with preeclampsia. While ADMA and SDMA levels were decreased in preeclampsia, the ADMA-SDMA ratio was not significantly different. Conclusions: Decreased DDAH and HO with preeclampsia suggest that they are important points in the regulatory pathways of NO and CO production that are altered in preeclampsia. The ADMA-SDMA ratio is not a useful test for preeclampsia.

Ehsanipoor, Robert M.; Fortson, Wilbert; Fitzmaurice, Laura E.; Liao, Wu-Xiang; Wing, Deborah A.; Chen, Dong-bao; Chan, Kenneth

2013-01-01

260

Infrared measurement and modeling of tropospheric carbon monoxide  

NASA Astrophysics Data System (ADS)

The purpose of this continued study is to model correctly the concentration of carbon monoxide (CO) in the troposphere of Harrisonburg, VA using an atmospheric modeling software program coupled with an experimental technique. In previous years, multiple raw data sets were collected using a technique known as gas filter correlation radiometry (GFCR) developed at NASA Langley Research Center. This technique utilizes the infrared (IR) radiance of the full moon and combines a ground-based IR data collection system with a blackbody calibration to yield a power value of the radiant stream. The raw data are processed by differencing a radiance stream obtained from the moon as passed through an evacuated cell against a cell containing a fixed concentration of CO. This power value is then compared with those simulated by the atmospheric modeling software HITRAN-PC. HITRAN-PC can simulate the atmosphere of Harrisonburg with a few key changes of input. It can then model the transmittance of the atmosphere, and by applying an algorithm developed in-house, we can correlate this transmission to a corresponding power value. The modeling is performed multiple times with various estimated values of CO, simulating clean and polluted conditions. Once the power value from the data and the power value from the modeling converge, the CO concentration is determined.

Bourne, Jenna E.; Bourne, Stephanie; Jenkins, Chelsea L.; Smith, Christopher M.

2003-04-01

261

Cr(110) oxidation probed by carbon monoxide chemisorption  

NASA Astrophysics Data System (ADS)

High resolution electron energy loss spectroscopy of chemisorbed carbon monoxide is used to distinguish between (1) an annealed, oxidized Cr(110) surface, (2) an intermediate, subsurface Cr(110) oxide, and (3) oxygen-dosed Cr(110). On the annealed oxide, weak signals are observed from both the dissociation-precursor (? 1-CO) and the terminally-bonded (? 2-CO) molecular CO binding states but only after relatively high CO exposures, reflecting greatly reduced sticking probabilities. However, on the surface with subsurface oxygen, both binding states are sequentially populated with sticking probabilities comparable to that of clean Cr(110); also, an increase in vCO from ~1975 to 2035 cm -1 is observed at high coverages of terminally-bonded ? 2-CO. Both the annealed-oxide and subsurface-oxide CO chemisorption results are in contrast to the selective poisoning of only ? 1-CO by chemisorbed atomic oxygen on Cr(110). Comparisons among the three oxygen containing surface (1) show how vibrational spectroscopy of chemically-inequivalent molecular binding states may be used as a probe of surface oxidation and (2) provide insights into the oxygen-CO surface chemistry.

Shinn, Neal D.

1989-04-01

262

Carbon monoxide poisoning in the 21st century  

PubMed Central

The world has experienced some very large shifts in the epidemiology of carbon monoxide poisoning, but it remains one of the most important toxicological global causes of morbidity and mortality. The diagnosis can be quickly confirmed with blood gases (pulse oximeters lack both sensitivity and specificity). Several strong predictors for serious neurological sequelae (prolonged loss of consciousness and elevated S100B) and reduced life expectancy (elevated troponin) are now reasonably well established. Despite this clearly defined high-risk group and extensive research into the pathophysiology, there has been little translation into better treatment. Much of the pathophysiological research has focused on hyperbaric oxygen. Yet it is apparent that clinical trials show little evidence for benefit from hyperbaric oxygen, and the most recent even raises the possibility of harm for repeated courses. More logical and promising potential antidotes have been under-researched, although recently both animal and small human studies suggest that erythropoietin may reduce S100B and prevent neurological sequelae. Major breakthroughs are likely to require further research on this and other treatments that may inhibit post-hypoxic inflammatory responses and apoptosis.

2014-01-01

263

Carbon monoxide fourth positive ultraviolet airglow emissions on Venus  

SciTech Connect

The ultraviolet spectrometer experiment aboard the Pioneer Venus orbiting spacecraft has recorded airglow spectra of the carbon monoxide (CO) fourth positive emission bands in the lambda 1250-1800 A spectra region. Extended duration of the PV mission since the December 4, 1978 orbit insertion has afforded opportunity to obtain many disc spectra, composite disc images and limb emission altitude profiles of the strongest (CO(A'..pi -->..X'..sigma../sup +/) electronic bands. Data have been analyzed in terms of high resolution theoretical synthetic spectra calculated from a detailed multiple scattering radiative transfer model which postulates population of the excited ..pi.. electronic state by the mechanisms of solar resonance absorption and photoelectron impact excitation of CO, excitation by solar ultraviolet photolysis and photoelectron impact dissociation of CO/sub 2/, and dissociative recombinatin of CO/sub 2//sup +/ ions with thermal electrons. The predominant emission sources prove to be solar resonance scattering and dissociative recombination for all bands except those of the v' = 14 vibrational progression which are excited solely by resonance absorption of solar Lyman-alpha. Agreement between theory and observations is quite good with discrepancies attributable to uncertainties in the solar flux and instrument calibration. The density distribution of CO molecules below the 137 km turbopause altitude is inferred from the (14,5) band limb emission profile.

Swanson, R.A.L.

1983-01-01

264

Reductive coupling of carbon monoxide to C sub 2 products  

SciTech Connect

Progress since the initiation of this two year award on May 1, 1988, has been divided into two areas for reporting purposes. We have been working on ideas described in the proposal submitted two years ago, and simultaneously we initiated chemistry in a distinct area in order to provide a springboard for the current proposal. Efforts directed toward reductive coupling of carbon monoxide have continued to focus on carbyne species as the central figure in coupling reactions. At the same time we have attempted to prepare intermediate oxidation state metal imido complexes with an eye to synthetic applications of nitrene transfer reagents. The results of carbyne chemistry, electrophilic addition reactions of anionic carbonyl and isonitrile complexes, and carbyne-carbonyl coupling reactions will be presented in this progress report, while the work with nitrene complexes will be included as preliminary results in the text of the accompanying proposal. The description of published work will be brief in this report; greater detail will be provided for unpublished material.

Templeton, J.L.

1989-11-01

265

Carbon Monoxide Modulates Apoptosis by Reinforcing Oxidative Metabolism in Astrocytes  

PubMed Central

Modulation of cerebral cell metabolism for improving the outcome of hypoxia-ischemia and reperfusion is a strategy yet to be explored. Because carbon monoxide (CO) is known to prevent cerebral cell death; herein the role of CO in the modulation of astrocytic metabolism, in particular, at the level of mitochondria was investigated. Low concentrations of CO partially inhibited oxidative stress-induced apoptosis in astrocytes, by preventing caspase-3 activation, mitochondrial potential depolarization, and plasmatic membrane permeability. CO exposure enhanced intracellular ATP generation, which was accompanied by an increase on specific oxygen consumption, a decrease on lactate production, and a reduction of glucose use, indicating an improvement of oxidative phosphorylation. Accordingly, CO increased cytochrome c oxidase (COX) enzymatic specific activity and stimulated mitochondrial biogenesis. In astrocytes, COX interacts with Bcl-2, which was verified by immunoprecipitation; this interaction is superior after 24 h of CO treatment. Furthermore, CO enhanced Bcl-2 expression in astrocytes. By silencing Bcl-2 expression with siRNA transfection, CO effects in astrocytes were prevented, namely: (i) inhibition of apoptosis, (ii) increase on ATP generation, (iii) stimulation of COX activity, and (iv) mitochondrial biogenesis. Thus, Bcl-2 expression is crucial for CO modulation of oxidative metabolism and for conferring cytoprotection. In conclusion, CO protects astrocytes against oxidative stress-induced apoptosis by improving metabolism functioning, particularly mitochondrial oxidative phosphorylation.

Almeida, Ana S.; Queiroga, Claudia S. F.; Sousa, Marcos F. Q.; Alves, Paula M.; Vieira, Helena L. A.

2012-01-01

266

Hydrogenation of carbon monoxide over nanostructured systems: A mechanochemical approach  

NASA Astrophysics Data System (ADS)

In this study we investigated the mechanochemical hydrogenation of carbon monoxide over nanostructured FeCo- and Mg 2Ni-based catalysts. To this aim powdered materials, prepared by mechanical alloying, were subjected to mechanical treatment under CO + H 2 atmosphere. A methodology to evaluate the activity of the solid catalysts on an absolute basis was developed. Conversion data were, indeed, expressed as turnover frequency, TOF, and related to the occurrence of ball to powder collision events through the mechanochemical turnover frequency parameter, MTOF. Differences in the catalytic activity and selectivity were observed for the two FeCo-based studied systems, the solid solution Fe 50Co 50 and its dispersion on TiO 2 support. As for the Mg 2Ni system, we explored the possibility to estimate the specific role of hydrogen pre-activation step. The catalytic properties of the mechanically alloyed Mg 2Ni system were compared with the conversion data shown by the same system pre-hydrogenated and subsequently milled under CO atmosphere.

Mulas, Gabriele; Campesi, Renato; Garroni, Sebastiano; Delogu, Francesco; Milanese, Chiara

2011-07-01

267

Carbon monoxide over the Amazon basin during the wet season  

SciTech Connect

Measurements of carbon monoxide (CO) were made over the Amazon Basin of Brazil during the 1987 wet season as part of the NASA Global Tropospheric Experiment/Amazon Boundary Layer Experiment (ABLE 2B). The distribution of CO over the altitude range sampled (0.15-4.5 km) was influenced by surface emissions from biological sources, long-range transport of pollutants from northern hemisphere sources, and by transport processes associated with local convective mixing. Surface sources are indicated by a qualitative interpretation of the typical pattern of decreasing concentrations with increasing altitude and increasing concentrations of CO at 0.15-km altitude during a transect from the Atlantic coast to the central basin. Atmospheric convective activity produced irregular patterns of variability at time scales of less than 1 hour over a localized area. The disruption of mixed layer growth and decay processes has a particularly important influence on CO concentrations in the daytime lower troposphere. Intrusions of northern hemisphere air into the central Amazon resulted in increased CO concentrations in the lower and midtroposphere. The correlation of CO with O{sub 3} was positive under conditions interpreted as being influenced by northern hemisphere air, and negative during all other meteorological conditions experienced in ABLE 2B.

Harriss, R.C. (Univ. of New Hampshire, Durham (USA)); Sachse, G.W.; Hill, G.F.; Gregory, G.L. (NASA Langley Research Center, Hampton, VA (USA)); Wade, L.O. (Planning Research Corp., Hampton, VA (USA))

1990-09-20

268

The immunomodulatory role of carbon monoxide during transplantation  

PubMed Central

The number of organ and tissue transplants has increased worldwide in recent decades. However, graft rejection, infections due to the use of immunosuppressive drugs and a shortage of graft donors remain major concerns. Carbon monoxide (CO) had long been regarded solely as a poisonous gas. Ultimately, physiological studies unveiled the endogenous production of CO, particularly by the heme oxygenase (HO)-1 enzyme, recognizing CO as a beneficial gas when used at therapeutic doses. The protective properties of CO led researchers to develop uses for it, resulting in devices and molecules that can deliver CO in vitro and in vivo. The resulting interest in clinical investigations was immediate. Studies regarding the CO/HO-1 modulation of immune responses and their effects on various immune disorders gave rise to transplantation research, where CO was shown to be essential in the protection against organ rejection in animal models. This review provides a perspective of how CO modulates the immune system to improve transplantation and suggests its use as a therapy in the field.

2013-01-01

269

In-utero carbon monoxide poisoning and multiple fetal abnormalities  

SciTech Connect

Carbon monoxide (CO) poisoning during pregnancy can lead to feto-maternal fatalities and stillbirths. Teratogenic effects have been reported. The authors strongly suspected an association between mild but chronic CO poisoning of the mother and major multiple malformations in the baby. Retrospective interviews of the mother disclosed that at 10 weeks' gestation, she had complained of headache and dizziness. At the same time, her 16-month-old daughter had an episode of unconsciousness. A faulty kitchen gas water-heater was suspected but the family did not have it repaired. The mother continued to have headaches regularly. During the 7th month of pregnancy, the daughter was found comatose. In the emergency ward, carboxyhemoglobins levels were 27.5% for the child and 14% for the pregnant mother. Both were treated with hyperbaric oxygen. Investigations by the gas company revealed a highly abnormal CO production from the kitchen and bathroom gas-water heaters: 120 and 100 parts per million, respectively, after 2 minutes of use.

Hennequin, Y.; Blum, D.; Vamos, E.; Steppe, M.; Goedseels, J.; Cavatorta, E. (Free Univ. of Brussels (Belgium). Queen Fabiola Children's Hospital)

1993-01-23

270

Carbon Monoxide in Exhaled Breath Testing and Therapeutics  

PubMed Central

Carbon monoxide (CO), a low molecular weight gas, is a ubiquitous environmental product of organic combustion, which is also produced endogenously in the body, as the byproduct of heme metabolism. CO binds to hemoglobin, resulting in decreased oxygen delivery to bodily tissues at toxicological concentrations. At physiological concentrations, CO may have endogenous roles as a potential signaling mediator in vascular function and cellular homeostasis. Exhaled CO (eCO), similar to exhaled nitric oxide (eNO), has been evaluated as a candidate breath biomarker of pathophysiological states, including smoking status, and inflammatory diseases of the lung and other organs. eCO values have been evaluated as potential indicators of inflammation in asthma, stable COPD and exacerbations, cystic fibrosis, lung cancer, or during surgery or critical care. The utility of eCO as a marker of inflammation, and potential diagnostic value remains incompletely characterized. Among other candidate “medicinal gases” with therapeutic potential, (e.g., NO and H2S), CO has been shown to act as an effective anti-inflammatory agent in preclinical animal models of inflammatory disease, acute lung injury, sepsis, ischemia/reperfusion injury and organ graft rejection. Current and future clinical trials will evaluate the clinical applicability of this gas as a biomarker and/or therapeutic in human disease.

Ryter, Stefan W.; Choi, Augustine M.K.

2013-01-01

271

Color evaluation of carbon monoxide treated porcine blood.  

PubMed

The stability of liquid porcine blood, treated with carbon monoxide (CO) at different pH values (7.40, 6.70, and 6.00) up to its complete saturation, was studied. Lowering the pH from 7.40 to 6.70 resulted in a decrease in the amount of CO necessary to obtain 100% carboxyhemoglobin. Further pH lowering to 6.00 did not result in additional reduction in the amount of gas. During 4 days of refrigerated storage CO treated liquid blood maintained, at every pH, a more stable and attractive red color than fresh blood, which was a result of an increase (P<0.05) of a(*) (redness) and b(*) (yellowness) values and no variation (P>0.05) on L(*) (lightness) value. Hue (h(*)) and chroma (C(*)) decreased in the untreated blood but not in the CO-treated blood. The results indicate that blood saturation with CO yields a product having greater potential for use in meat products without compromising its visual appearance. PMID:22062526

Fontes, P R; Gomide, L A M; Ramos, E M; Stringheta, P C; Parreiras, J F M

2004-12-01

272

Inhaled Carbon Monoxide Provides Cerebral Cytoprotection in Pigs  

PubMed Central

Carbon monoxide (CO) at low concentrations imparts protective effects in numerous preclinical small animal models of brain injury. Evidence of protection in large animal models of cerebral injury, however, has not been tested. Neurologic deficits following open heart surgery are likely related in part to ischemia reperfusion injury that occurs during cardiopulmonary bypass surgery. Using a model of deep hypothermic circulatory arrest (DHCA) in piglets, we evaluated the effects of CO to reduce cerebral injury. DHCA and cardiopulmonary bypass (CPB) induced significant alterations in metabolic demands, including a decrease in the oxygen/glucose index (OGI), an increase in lactate/glucose index (LGI) and a rise in cerebral blood pressure that ultimately resulted in increased cell death in the neocortex and hippocampus that was completely abrogated in piglets preconditioned with a low, safe dose of CO. Moreover CO-treated animals maintained normal, pre-CPB OGI and LGI and corresponding cerebral sinus pressures with no change in systemic hemodynamics or metabolic intermediates. Collectively, our data demonstrate that inhaled CO may be beneficial in preventing cerebral injury resulting from DHCA and offer important therapeutic options in newborns undergoing DHCA for open heart surgery.

Mahan, Vicki L.; Zurakowski, David

2012-01-01

273

Molybdopterin in carbon monoxide oxidase from carboxydotrophic bacteria.  

PubMed Central

The carbon monoxide oxidases (COXs) purified from the carboxydotrophic bacteria Pseudomonas carboxydohydrogena and Pseudomonas carboxydoflava were found to be molybdenum hydroxylases, identical in cofactor composition and spectral properties to the recently characterized enzyme from Pseudomonas carboxydovorans (O. Meyer, J. Biol. Chem. 257:1333-1341, 1982). All three enzymes exhibited a cofactor composition of two flavin adenine dinucleotides, two molybdenums, eight irons and eight labile sulfides per dimeric molecule, typical for molybdenum-containing iron-sulfur flavoproteins. The millimolar extinction coefficient of the COXs at 450 nm was 72 (per two flavin adenine dinucleotides), a value similar to that of milk xanthine oxidase and chicken liver xanthine dehydrogenase at 450 nm. That molybdopterin, the novel prosthetic group of the molybdenum cofactor of a variety of molybdoenzymes (J. Johnson and K. V. Rajagopalan, Proc. Natl. Acad. Sci. U.S.A. 79:6856-6860, 1982) is also a constituent of COXs from carboxydotrophic bacteria is indicated by the formation of identical fluorescent cofactor derivatives, by complementation of the nitrate reductase activity in extracts of Neurospora crassa nit-l, and by the presence of organic phosphate additional to flavin adenine dinucleotides. Molybdopterin is tightly but noncovalently bound to the protein. COX, sulfite oxidase, xanthine oxidase, and xanthine dehydrogenase each contains 2 mol of molybdopterin per mol of enzyme. The presence of a trichloroacetic acid-releasable, so-far-unidentified, phosphorous-containing moiety in COX is suggested by the results of phosphate analysis.

Meyer, O; Rajagopalan, K V

1984-01-01

274

Continuous monitoring of carbon monoxide in a deep street canyon  

NASA Astrophysics Data System (ADS)

The results of a 1-week continuous monitoring campaign of carbon monoxide in a deep street canyon in the city of Naples are reported. CO was selected as a passive pollutant emitted by vehicle exhausts. The geometry of the canyon is: width W=5.8m and height H=33m (aspect ratio AR= H/ W=5.7). The monitoring campaign was carried out from 14 to 20 June 2006. CO concentration level was measured at pedestrian level ( h=2.5m) and roof top level ( h=25m). In the same period traffic flow in the street canyon was manually measured and the CO emission rate from vehicle exhausts was evaluated using the COPERT procedure. Meteorological conditions (wind velocity and direction) are also reported and their effect on CO concentration level in the canyon is discussed. Due to its geometry the street canyon monitored may be considered almost ideal. The results show that the deep street canyon is a "hot spot" compared with roads with high traffic flows in the urban area of Naples, and that significant differences exist between concentration levels at pedestrian and roof top level. Some insights into the effect and relative importance of meteorological parameters on the air quality in the canyon are also given. The monitoring data collected have been made available on the web and can be used by other researchers to test air dispersion models.

Murena, Fabio; Favale, Giuseppe

275

Carbon monoxide and methane over Canada: July - August 1990  

NASA Technical Reports Server (NTRS)

Carbon monoxide (CO) and methane (CH4) were measured in the 0.15- to 6-km portion of the troposphere over subarctic and boreal landscapes of midcontinent and eastern Canada during July - August 1990. In the mid-continent region, Arctic air entering the region was characterized by relatively uniform CO concentrations (86-108 parts per billion by volume (ppbv)) and CH4 concentrations (1729-1764 ppbv). Local biomass burning and long-range transport of CO into the area from industrial/urban sources and distant fires did frequently produce enhanced and variable concentrations. Emissions of CH4 from the Hudson Bay lowlands was the primary source for enhanced and variable concentrations, especially at altitudes of 0.15-1 km. In eastern Canada, most of the observed variability in CO and CH4 was similar in origin to the phenomena described for the midcontinent region. However, unexpectedly low concentrations of CO (51 ppbv) and CH4 (1688 ppbv) were measured in the midtroposphere on several flights. Combined meteorological and chemical data indicated that the low CO-CH4 events were the result of long-range transport of tropical Pacific marine air to subarctic latitudes.

Harriss, R. C.; Sachse, G. W.; Collins, J. E., Jr.; Wade, L.; Bartlett, K. B.; Talbot, R. W.; Browell, E. V.; Barrie, L. A.; Hill, G. F.; Burney, L. G.

1994-01-01

276

A general circulation model study of atmospheric carbon monoxide  

NASA Technical Reports Server (NTRS)

The carbon monoxide cycle is studied by incorporating the known and hypothetical sources and sinks in a tracer model that uses the winds generated by a general circulation model. Photochemical production and loss terms, which depend on OH radical concentrations, are calculated in an interactive fashion. The computed global distribution and seasonal variations of CO are compared with observations to obtain constraints on the distribution and magnitude of the sources and sinks of CO, and on the tropospheric abundance of OH. The simplest model that accounts for available observations requires a low latitude plant source of about 1.3 x 10 to the 15th g/yr, in addition to sources from incomplete combustion of fossil fuels and oxidation of methane. The globally averaged OH concentration calculated in the model is 750,000/cu cm. Models that calculate globally averaged OH concentrations much lower than this nominal value are not consistent with the observed variability of CO. Such models are also inconsistent with measurements of CO isotopic abundances, which imply the existence of plant sources.

Pinto, J. P.; Rind, D.; Russell, G. L.; Lerner, J. A.; Hansen, J. E.; Yung, Y. L.; Hameed, S.

1983-01-01

277

Emergency department visits for carbon monoxide poisoning in LA.  

PubMed

Carbon monoxide (CO) poisoning is preventable, yet it remains one of the most common causes of poisoning in the United States. This analysis was performed to estimate the number of emergency department (ED) visits in 2010 in Louisiana for all-cause (fire-related, non-fire, and unknown) unintentional CO poisoning. Results demonstrate approximately 1,696,746 total ED visits occurred in 2010. Among these, an estimated 116 individuals were diagnosed with CO poisoning (68 CO cases per million ED visits; 26.2 CO cases per million population). Emergency Department visits for CO poisoning occurred most frequently in the winter months. Caddo, Jefferson, and Orleans parishes had the highest numbers of CO poisonings in 2010. The most common symptoms included headache, hypertension, nausea, and dizziness. The ED database presented more cases of the most common CO poisoning cases (non-fatal) than previously used surveillance databases. This study demonstrated the utility and importance of ED data as a surveillance tool. PMID:23431671

Katner, Adrienne; Peak, Kate; Sun, Mei-Hung; Badakhsh, Roshan; Woods, Adrienne; Soileau, Shannon; Dugas, Dianne

2012-01-01

278

Carbon monoxide inhalation increases microparticles causing vascular and CNS dysfunction  

PubMed Central

We hypothesized that circulating microparticles (MPs) play a role in pro-inflammatory effects associated with carbon monoxide (CO) inhalation. Mice exposed for 1 h to 100 ppm CO or more exhibit increases in circulating MPs derived from a variety of vascular cells as well as neutrophil activation. Tissue injury was quantified as 2000 kDa dextran leakage from vessels and as neutrophil sequestration in the brain and skeletal muscle; and central nervous system nerve dysfunction was documented as broadening of the neurohypophysial action potential (AP). Indices of injury occurred following exposures to 1000 ppm for 1 h or to 1000 ppm for 40 min followed by 3000 ppm for 20 min. MPs were implicated in causing injuries because infusing the surfactant MP lytic agent, polyethylene glycol telomere B (PEGtB) abrogated elevations in MPs, vascular leak, neutrophil sequestration and AP prolongation. These manifestations of tissue injury also did not occur in mice lacking myeloperoxidase. Vascular leakage and AP prolongation were produced in naïve mice infused with MPs that had been obtained from CO poisoned mice, but this did not occur with MPs obtained from control mice. We conclude that CO poisoning triggers elevations of MPs that activate neutrophils which subsequently cause tissue injuries.

Xu, Jiajun; Yang, Ming; Kosterin, Paul; Salzberg, Brian M.; Milovanova, Tatyana N.; Bhopale, Veena M.; Thom, Stephen R.

2014-01-01

279

Carbon Monoxide, Reactive Oxygen Signaling, and Oxidative Stress  

PubMed Central

The ubiquitous gas, carbon monoxide (CO), is of substantial biological importance, but apart from its affinity for reduced transition metals, particularly heme-iron, it is surprisingly non-reactive—as is the ferrous-carbonyl—in living systems. CO does form strong complexes with heme proteins for which molecular O2 is the preferred ligand and to which are attributed diverse physiological, adaptive, and toxic effects. Lately, it has become apparent that both exogenous and endogenous CO produced by heme oxygenase engender a pro-oxidant milieu in aerobic mammalian cells which initiates signaling related to reactive oxygen species (ROS) generation. ROS signaling contingent on CO can be segregated by CO concentration-time effects on cellular function, by the location of heme proteins, e.g. mitochondrial or non-mitochondrial sites, or by specific oxidation-reduction (redox) reactions. The fundamental responses to CO involve overt physiological regulatory events, such as activation of redox-sensitive transcription factors or stress-activated kinases, which institute compensatory expression of anti-oxidant enzymes and other adaptations to oxidative stress. In contrast, responses originating from highly elevated or protracted CO exposures tend to be non-specific, produce untoward biological oxidations, and interfere with homeostasis. This brief overview provides a conceptual framework for understanding CO biology in terms of this physiological-pathological hierarchy.

Piantadosi, Claude A.

2008-01-01

280

Partial oxidation of methane, methanol, and mixtures of methane and methanol, methane and ethane, and methane, carbon dioxide, and carbon monoxide  

Microsoft Academic Search

The homogeneous partial oxidation of methane involves the primary reactions of methane oxidation as well as the secondary reactions with the reaction products formaldehyde, methanol, and carbon monoxide. The complex free-radical set of reactions are modeled using a pseudo-first-order reaction parallel-series network of the three reactions: methane to methanol, methane to carbon monoxide, and methanol to carbon monoxide. The secondary

Jinwoo Chun; Rayford G. Anthony

1993-01-01

281

CROSS-CORRELATIONS AS A COSMOLOGICAL CARBON MONOXIDE DETECTOR  

SciTech Connect

We present a new procedure to measure the large-scale carbon monoxide (CO) emissions across cosmic history. As a tracer of large-scale structure (LSS), the CO gas content as a function of redshift can be quantified by its three-dimensional fluctuation power spectra. Furthermore, cross-correlating CO emission with other LSS tracers offers a way to measure the emission as a function of scale and redshift. Here we introduce the model relevant for such a cross-correlation measurement between CO and other LSS tracers, and between different CO rotational lines. We propose a novel use of cosmic microwave background (CMB) data and attempt to extract redshifted CO emissions embedded in the Wilkinson Microwave Anisotropy Probe (WMAP) data set. We cross-correlate the all-sky WMAP7 data with LSS data sets, namely, the photometric quasar sample and the luminous red galaxy sample from the Sloan Digital Sky Survey Data Releases 6 and 7, respectively. We are unable to detect a cross-correlation signal with either CO(1-0) or CO(2-1) lines, mainly due to the instrumental noise in the WMAP data. However, we are able to rule out models more than three times greater than our more optimistic model. We discuss the cross-correlation signal from the thermal Sunyaev-Zeldovich effect and dust as potential contaminants, and quantify their impact for our CO measurements. We discuss forecasts for current CMB experiments and a hypothetical future CO-focused experiment, and propose to cross-correlate CO temperature data with the Hobby-Eberly Telescope Dark Energy Experiment Ly{alpha}-emitter sample, for which a signal-to-noise ratio of 58 is possible.

Pullen, Anthony R.; Dore, Olivier [NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, MS 169-237, Pasadena, CA 91109 (United States); Chang, Tzu-Ching [IAA, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Lidz, Adam, E-mail: anthony.r.pullen@jpl.nasa.gov [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)

2013-05-01

282

Predictors for delayed encephalopathy following acute carbon monoxide poisoning  

PubMed Central

Background In Japan, many carbon monoxide (CO) poisoning cases are transported to emergency settings, making treatment and prognostic assessment an urgent task. However, there is currently no reliable means to predict whether “delayed neuropsychiatric sequelae (DNS)” will develop after acute CO poisoning. This study is intended to find out risk factors for the development of DNS and to characterize the clinical course following the development of DNS in acute CO poisoning cases. Methods This is a retrospective cohort study of 79 consecutive patients treated at a single institution for CO poisoning. This study included 79 cases of acute CO poisoning admitted to our emergency department after attempted suicide, who were divided into two groups consisting of 13 cases who developed DNS and 66 cases who did not. The two groups were compared and analyzed in terms of clinical symptoms, laboratory findings, etc. Results Predictors for the development of DNS following acute CO poisoning included: serious consciousness disturbance at emergency admission; head CT findings indicating hypoxic encephalopathy; hematology findings including high creatine kinase, creatine kinase-MB and lactate dehydrogenase levels; and low Global Assessment Scale scores. The clinical course of the DNS-developing cases was characterized by prolonged hospital stay and a larger number of hyperbaric oxygen (HBO) therapy sessions. Conclusion In patients with the characteristics identified in this study, administration of HBO therapy should be proactively considered after informing their family, at initial stage, of the risk of developing DNS, and at least 5 weeks’ follow-up to watch for the development of DNS is considered necessary.

2014-01-01

283

Cross-correlations as a Cosmological Carbon Monoxide Detector  

NASA Astrophysics Data System (ADS)

We present a new procedure to measure the large-scale carbon monoxide (CO) emissions across cosmic history. As a tracer of large-scale structure (LSS), the CO gas content as a function of redshift can be quantified by its three-dimensional fluctuation power spectra. Furthermore, cross-correlating CO emission with other LSS tracers offers a way to measure the emission as a function of scale and redshift. Here we introduce the model relevant for such a cross-correlation measurement between CO and other LSS tracers, and between different CO rotational lines. We propose a novel use of cosmic microwave background (CMB) data and attempt to extract redshifted CO emissions embedded in the Wilkinson Microwave Anisotropy Probe (WMAP) data set. We cross-correlate the all-sky WMAP7 data with LSS data sets, namely, the photometric quasar sample and the luminous red galaxy sample from the Sloan Digital Sky Survey Data Releases 6 and 7, respectively. We are unable to detect a cross-correlation signal with either CO(1-0) or CO(2-1) lines, mainly due to the instrumental noise in the WMAP data. However, we are able to rule out models more than three times greater than our more optimistic model. We discuss the cross-correlation signal from the thermal Sunyaev-Zeldovich effect and dust as potential contaminants, and quantify their impact for our CO measurements. We discuss forecasts for current CMB experiments and a hypothetical future CO-focused experiment, and propose to cross-correlate CO temperature data with the Hobby-Eberly Telescope Dark Energy Experiment Ly?-emitter sample, for which a signal-to-noise ratio of 58 is possible.

Pullen, Anthony R.; Chang, Tzu-Ching; Doré, Olivier; Lidz, Adam

2013-05-01

284

Carbon monoxide exposures--United States, 2000-2009.  

PubMed

Carbon monoxide (CO) poisoning is a leading cause of unintentional poisoning deaths in the United States. CO is an odorless, colorless gas that usually remains undetectable until exposure results in injury or death. CO poisoning is preventable; nonetheless, unintentional, non--fire-related CO poisoning is responsible for approximately 15,000 emergency department visits and nearly 500 deaths annually in the United States. National estimates of CO exposures have been based on secondary data sources, such as hospital administrative records, and are limited to exposures treated within the health-care system. To describe more completely the national burden of CO exposure and risk factors associated with vulnerable populations, CDC used data from the National Poison Data System (NPDS) to characterize reported unintentional, non--fire-related CO exposures, including those that were managed at the site of exposure and were not treated at a health-care facility. Among 68,316 CO exposures reported to poison centers during 2000--2009, a total of 30,798 (45.1%) were managed at the site of exposure with instructions from the poison center by telephone, 36,691 (53.7%) were treated at a health-care facility, and the management site for the remainder was unknown. Although symptoms varied slightly between persons managed on-site and those treated at a health-care facility, most CO exposures occurred at home and most often involved females, children aged ?17 years, and adults aged 18--44 years. Surveillance and analysis of data from NPDS and secondary sources might provide a more comprehensive description of the burden of CO exposure in the United States and assist in the development of interventions better targeted to high-risk populations. PMID:21814164

2011-08-01

285

Carbon monoxide induces chromatin remodelling to facilitate endothelial cell migration.  

PubMed

Vascular injury to vessel endothelial cells (EC), caused by either mechanical damage or chronic inflammation, is still awaiting effective therapies. In the present study we hypothesised that carbon monoxide (CO) acts on the nuclear receptor Rev-erb? to induce chromatin modification and endothelial cell migration. We demonstrate that administration of low, safe doses of exogenous CO enhances endothelial cell (EC) migration, which occurs in part through chromatin remodelling and histone H3 acetylation. Further, we show that the effects of CO are dependent on inhibition of phosphorylation of glycogen synthase kinase-3 ? (GSK3?), activation of haem synthesis, and increased expression of Rev-erb?. Rev-erb? is a haem-containing transcription factor which in response to CO binds to target DNA, recruits the Histone Deacetylase/nuclear Receptor Corepressor (HDAC/N-CoR) complex, and regulates transcription of genes responsible for endothelial cell migration and angiogenesis. Decreased levels of Rev-erb? in chimeric mice after bone marrow transplant from Rev-erb? following bone marrow transplantation from rev-erb+/- mice resulted in loss of protective effects of CO against neointima formation after wire injury. Collectively, CO modifies chromatin structure through enhanced acetylation of histone H3 via a GSK3?-Rev-erb?-mediated pathway to increase EC migration. We propose that CO enhances vessel repair following injury in part by regulating EPC/EC motility via Rev-erb?. Thus, inhaled CO may be beneficial in the treatment of vascular syndromes associated with dysregulated thrombosis, wound healing, and angiogenesis. PMID:24477332

Li, Mailin; Gallo, David; Csizmadia, Eva; Otterbein, Leo E; Wegiel, Barbara

2014-05-01

286

Monitoring ambient air quality with carbon monoxide sensor-based wireless network  

Microsoft Academic Search

Introduction Carbon Monoxide (CO) is a poisonous air pollutant produced from the incomplete oxidation of carbon during the combustion process. It has a direct effect on the human body due to its affinity for blood hemoglobin, which inhibits the absorption of oxygen to the blood. The formation of carboxyhemoglobin complex can profoundly affect human health both on an acute and

Demin Wang; Dharma P. Agrawal; Wassana Toruksa; Chaichana Chaiwatpongsakorn; Mingming Lu; Tim C. Keener

2010-01-01

287

Mixed metal oxide catalyst for producing low molecular weight hydrocarbons from carbon monoxide and hydrogen  

Microsoft Academic Search

Low molecular weight hydrocarbons are produced by contacting carbon monoxide and hydrogen at elevated temperatures and pressures with a catalyst comprising oxides of chromium, molybdenum and\\/or tungsten, copper, thorium or uranium and at least one alkali or alkaline earth metal. Catalysts are provided which are prepared by the procedure of adding an alkali or alkaline earth metal carbonate to an

M. F. Lemanski; W. R. Kliewer

1984-01-01

288

Process for producing lowmolecular weight hydrocarbons from carbon monoxide and hydrogen  

Microsoft Academic Search

Low molecular weight hydrocarbons are produced by contacting carbon monoxide and hydrogen at elevated temperatures and pressures with a catalyst comprising oxides of chromium, molybdenum and\\/or tungsten, copper, thorium or uranium and at least one alkali or alkaline earth metal. Catalysts are provided which are prepared by the procedure of adding an alkali or alkaline earth metal carbonate to an

M. F. Lemanski; W. R. Kliewer

1985-01-01

289

Compact Reconnaissance Imaging Spectrometer Observations of Water Vapor and Carbon Monoxide  

NASA Technical Reports Server (NTRS)

The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard the Mars Reconnaissance Orbiter (MRO) spacecraft began taking observations in September 2006 and has now collected more than a full Martian year of data. Retrievals performed using the near-infrared spectra obtained by CRISM are used to characterize the seasonal and spatial variation of the column abundance of water vapor and the column-averaged mixing ratio of carbon monoxide. CRISM retrievals show nominal behavior in water vapor during northern hemisphere spring and summer with maximum abundance reaching 50 precipitable micrometers. Water vapor abundance during the southern hemisphere spring and summer appears significantly reduced compared to observations by other instruments taken during previous years. The CRISM retrievals show the seasonally and globally averaged carbon monoxide mixing ratio to be 700 ppm, but with strong seasonal variations at high latitudes. The summertime near-polar carbon monoxide mixing ratio falls to 200 ppm in the south and 400 ppm in the north as carbon dioxide sublimates from the seasonal polar ice caps and dilutes noncondensable species including carbon monoxide. At low latitudes, the carbon monoxide mixing ratio varies in response to the mean seasonal cycle of surface pressure.

Smith, Michael D.; Wolff, Michael J.; Clancy, R. Todd; Murchie, Scott L.

2009-01-01

290

A population-based exposure assessment methodology for carbon monoxide: Development of a carbon monoxide passive sampler and occupational dosimeter  

SciTech Connect

Two devices, an occupational carbon monoxide (CO) dosimeter (LOCD), and an indoor air quality (IAQ) passive sampler were developed for use in population-based CO exposure assessment studies. CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10{sup -4}). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the national ambient air quality standard. No CO exposure measurement technology is presently available for affordable population-based CO exposure assessment studies. The LOCD and IAQ Passive Sampler were tested in the laboratory and field. The palladium-molybdenum based CO sensor was designed into a compact diffusion tube sampler that can be worn. Time-weighted-average (TWA) CO exposure of the device is quantified by a simple spectrophotometric measurement. The LOCD and IAQ Passive Sampler were tested over an exposure range of 40 to 700 ppm-hours and 200 to 4200 ppm-hours, respectively. Both devices were capable of measuring precisely (relative standard deviation <20%), with low bias (<10%). The LOCD was screened for interferences by temperature, humidity, and organic and inorganic gases. Temperature effects were small in the range of 10{degrees}C to 30{degrees}C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.

Apte, M.G.

1997-09-01

291

Theoretical study of the interactions of carbon monoxide with Rh-decorated (8,0) single-walled carbon nanotubes  

Microsoft Academic Search

Recent laboratory studies have shown that metal nanoparticles-decorated single-walled carbon nanotubes (SWCNTs) can be used to detect carbon monoxide (CO) gases at room temperature, which is known not able to be adsorbed on pure SWCNTs. In this paper, we investigated the Rh-decorated (8,0) SWCNT and its interaction with CO gases by using density functional theory (DFT) methods. Upon Rh atom

Jing-Xiang Zhao; Yi-Hong Ding

2008-01-01

292

40 CFR 60.103 - Standard for carbon monoxide.  

Code of Federal Regulations, 2013 CFR

...fluid catalytic cracking unit catalyst regenerator that is subject to the requirements...fluid catalytic cracking unit catalyst regenerator will be operated, or 180 days after...fluid catalytic cracking unit catalyst regenerator any gases that contain carbon...

2013-07-01

293

[Carboxyhemoglobin concentration in carbon monoxide poisoning. Critical appraisal of the predictive value].  

PubMed

In cases of unclear depression of conciousness, arrhythmia and symptoms of cardiac insufficiency inadvertent carbon monoxide intoxication should always be taken into consideration. Rapid diagnosis of acute carbon monoxide intoxication with mostly unspecific symptoms requires an immediate supply of high dose oxygen which enables a distinct reduction of mortality and long-term morbidity. Levels of carboxyhemoglobin, however, should not be used as a parameter to decide whether to supply normobaric or the more efficient hyperbaric oxygen. There is no sufficient coherence between carboxyhemoglobin blood levels and clinical symptoms. Increased carboxyhemoglobin concentrations help to diagnose acute carbon monoxide intoxication but do not allow conclusions to be drawn about possible long-term neuropsychiatric or cardiac consequences. PMID:20442979

Köthe, L; Radke, J

2010-06-01

294

Carbon monoxide-induced suspended animation protects against hypoxic damage in Caenorhabditis elegans.  

PubMed

Oxygen deprivation is a major cause of cellular damage and death. Here we demonstrate that Caenorhabditis elegans embryos, which can survive both in anoxia (<0.001 kPa O(2)) by entering into suspended animation and in mild hypoxia (0.25-1 kPa O(2)) through a hypoxia-inducible factor 1-mediated response, cannot survive in intermediate concentrations of oxygen, between 0.01 and 0.1 kPa O(2). Moreover, we show that carbon monoxide can protect C. elegans embryos against hypoxic damage in this sensitive range. Carbon monoxide can also rescue the hypoxia-sensitive mutant hif-1(ia04) from lethality in hypoxia. This work defines the oxygen tensions over which hypoxic damage occurs in C. elegans embryos and demonstrates that carbon monoxide can prevent this damage by inducing suspended animation. PMID:15184665

Nystul, Todd G; Roth, Mark B

2004-06-15

295

Substantially isotactic, linear, alternating copolymers of carbon monoxide and an olefin  

SciTech Connect

The compound, [Pd(Me-DUPHOS)(MeCN).sub.2 ](BF.sub.4).sub.2, [Me-DUPHOS: 1,2-bis(2,5-dimethylphospholano)benzene] is an effective catalyst for the highly enantioselective, alternating copolymerization of olefins, such as aliphatic .alpha.-olefins, with carbon monoxide to form optically active, isotactic polymers which can serve as excellent starting materials for the synthesis of other classes of chiral polymers. For example, the complete reduction of a propylene-carbon monoxide copolymer resulted in the formation of a novel, optically active poly(1,4-alcohol). Also, the previously described catalyst is a catalyst for the novel alternating isomerization cooligomerization of 2-butene with carbon monoxide to form optically active, isotactic poly(1,5-ketone)

Sen, Ayusman (State College, PA); Jiang, Zhaozhong (State College, PA)

1996-01-01

296

Substantially isotactic, linear, alternating copolymers of carbon monoxide and an olefin  

SciTech Connect

The compound, [Pd(Me-DUPHOS)(MeCN){sub 2}](BF{sub 4}){sub 2}, [Me-DUPHOS: 1,2-bis(2,5-dimethylphospholano)benzene] is an effective catalyst for the highly enantioselective, alternating copolymerization of olefins, such as aliphatic {alpha}-olefins, with carbon monoxide to form optically active, isotactic polymers which can serve as excellent starting materials for the synthesis of other classes of chiral polymers. For example, the complete reduction of a propylene-carbon monoxide copolymer resulted in the formation of a novel, optically active poly(1,4-alcohol). Also, the previously described catalyst is a catalyst for the novel alternating isomerization cooligomerization of 2-butene with carbon monoxide to form optically active, isotactic poly(1,5-ketone).

Sen, A.; Jiang, Z.

1996-05-28

297

Occupational carbon monoxide violations in the State of Washington, 1994-1999.  

PubMed

Occupational exposure to carbon monoxide continues to cause a number of injuries and deaths. This study reviewed the State of Washington OSHA inspection records for occupational safety or health violations related to carbon monoxide for the time period 1994-1999 to assess the agency's efforts and further identify and characterize causative factors. Inspection data were also compared with carbon monoxide claims data from a companion study to determine if the agency was visiting the most at risk work operations. Inspections were identified by searching computerized violation texts for "carbon monoxide" or "CO." The study found 142 inspections with one or more carbon monoxide violations. Inspections were spread over 84 different 4-digit Standard Industrial Classification codes. Most inspections were initiated as a result of a complaint or other informant. Inspections were predominantly in construction and manufacturing, whereas carbon monoxide claims were mores evenly distributed between the major industries. Inspections also may have failed to find violations for some types of equipment responsible for carbon monoxide claims. Forklifts were the source of carbon monoxide most often associated with a violation, followed by compressors for respirators, auto/truck/bus, and temporary heating devices. Inspections in response to poisonings found common factors associated with lack of recognition and failure to use or maintain equipment and ventilation. Some work sites with one or more poisonings were not being inspected. Only 10 of the 51 incidents with industrial insurance claim reports of carboxyhemoglobin at or above 20 percent were inspected. Further, it was found more preventive efforts should be targeted at cold storage operations and certain warehouse and construction activities. It is proposed that more specific standards, both consensus and regulatory, would provide additional risk reduction. Reliance upon safe work practices as a primary method of control in the use of fuel-powered equipment in cold storage or other enclosed and unventilated environments needs to be prohibited. The study further demonstrates how inspection and industrial insurance records can assist with preventive efforts and better focus an agency's efforts. PMID:12083171

Lofgren, Don J

2002-07-01

298

Accidental carbon monoxide poisoning during yagya for faith healing--a case report.  

PubMed

A 20-year-old female and a 45-year-old male were found lying dead on the floor with frothand vomitus stain present over mouth, nose and face in a closed room. An earthen bowl with incomplete burnt woods, flowers, food materials, agarbati, etc, was also found lying near the body of the two deceased. The cause of death, established by autopsy and toxicological examination was carbon monoxide poisoning in both victims. The source of carbon monoxide was incomplete burnt woods used for yagya during puja (a faith healing practice) for bearing children. PMID:24592764

Behera, C; Millo, T M; Jaiswal, A; Dogra, T D

2013-03-01

299

The photochemistry of methane and carbon monoxide in the troposphere in 1950 and 1985  

NASA Technical Reports Server (NTRS)

The roughly 1 percent/year increase in tropospheric methane and roughly 2 percent/year increase in tropospheric carbon monoxide deduced from recent analyses of ground-based solar infrared spectra recorded in 1950 and 1951 have very important implications for the photochemistry and chemistry of the troposphere. Photochemical calculations indicate that as a result of the increase of methane and carbon monoxide since 1950-51, levels of the hydroxyl radical, the key species in the photochemistry of the troposphere, may have decreased by about 25 percent.

Levine, J. S.; Rinsland, C. P.; Tennille, G. M.

1985-01-01

300

On the effect of carbon monoxide addition on soot formation in a laminar ethylene/air coflow diffusion flame  

SciTech Connect

The effect of carbon monoxide addition on soot formation in an ethylene/air diffusion flame is investigated by experiment and detailed numerical simulation. The paper focuses on the chemical effect of carbon monoxide addition by comparing the results of carbon monoxide and nitrogen diluted flames. Both experiment and simulation show that although overall the addition of carbon monoxide monotonically reduces the formation of soot, the chemical effect promotes the formation of soot in an ethylene/air diffusion flame. The further analysis of the details of the numerical result suggests that the chemical effect of carbon monoxide addition may be caused by the modifications to the flame temperature, soot surface growth and oxidation reactions. Flame temperature increases relative to a nitrogen diluted flame, which results in a higher surface growth rate, when carbon monoxide is added. Furthermore, the addition of carbon monoxide increases the concentration of H radical owing to the intensified forward rate of the reaction CO + OH = CO{sub 2} + H and therefore increases the surface growth reaction rates. The addition of carbon monoxide also slows the oxidation rate of soot because the same reaction CO + OH = CO{sub 2} + H results in a lower concentration of OH. (author)

Guo, Hongsheng; Thomson, Kevin A.; Smallwood, Gregory J. [Institute for Chemical Process and Environmental Technology, National Research Council of (Canada)

2009-06-15

301

Hydroxyl, water, ammonia, carbon monoxide and neutral carbon towards the Sgr A complex  

NASA Astrophysics Data System (ADS)

We observed Hydroxyl, water, ammonia, carbon monoxide and neutral carbon towards the +50 km s-1 cloud (M-0.02-0.07), the circumnuclear disk (CND) and the +20 km s-1 (M-0.13-0.08) cloud in the Sgr A complex with the VLA, Odin and SEST. Strong OH absorption, H2O emission and absorption lines were seen at all three positions. Strong C18O emissions were seen towards the +50 and +20 km s-1 clouds. The CND is rich in H2O and OH, and these abundances are considerably higher than in the surrounding clouds, indicating that shocks, star formation and clump collisions prevail in those objects. A comparison with the literature reveals that it is likely that PDR chemistry including grain surface reactions, and perhaps also the influences of shocks has led to the observed abundances of the observed molecular species studied here. In the redward high-velocity line wings of both the +50 and +20 km s-1 clouds and the CND, the very high H2O abundances are suggested to be caused by the combined action of shock desorption from icy grain mantles and high-temperature, gas-phase shock chemistry. Only three of the molecules are briefly discussed here. For OH and H2O three of the nine observed positions are shown, while a map of the C18O emission is provided. An extensive paper was recently published with Open Access (Karlsson et al. 2013, A&A 554, A141).

Karlsson, R.; Sandqvist, Aa.; Hjalmarson, Ã.; Winnberg, A.; Fathi, K.; Frisk, U.; Olberg, M.

2014-05-01

302

Influence of water table on carbon dioxide, carbon monoxide, and methane fluxes from taiga bog microcosms  

SciTech Connect

Hydrological changes, particularly alterations in water table level, may largely overshadow the more direct effects of global temperature increase upon carbon cycling in arctic and subarctic wetlands. Frozen cores (n=40) of intact soils and vegetation were collected from a bog near Fairbanks, Alaska, and fluxes of CO{sub 2}, CH{sub 4}, and Co in response to water table variation were studied under controlled conditions in the Duke University phytotron. Core microcosms thawed to a 20-cm depth over 30 days under a 20 hour photoperiod with a day/night temperature regime of 20/10{degrees}C. After 30 days the water table in 20 microcosms was decreased from the soil surface to -15 cm and maintained at the soil surface in 20 control cores. Outward fluxes of CO{sub 2} (9-16 g m{sup -2}d{sup -1}) and CO (3-4 mg m{sup -2}d{sup -1}) were greatest during early thaw and decreased to near zero for both gases before the water table treatment started. Lower water table tripled CO{sub 2} flux to the atmosphere when compared with control cores. Carbon monoxide was emitted at low rates from high water table cores and consumed by low water table cores. Methane fluxes were low (<1 mg m{sup -2}d{sup -1}) in all cores during thaw. High water table cores increased CH{sub 4} flux to 8-9 mg m{sup -2}d{sup -1} over 70 days and remained high relative to the low water table cores (<0.74 mg m{sup -2}d{sup -1}). Although drying of wetland taiga soils may decrease CH{sub 4} emissions to the atmosphere, the associated increase in CO{sub 2} due to aerobic respiration will likely increase the global warming potential of gas emissions from these soils. 43 refs., 4 figs.

Funk, D.W.; Pullmann, E.R.; Peterson, K.M. [Univ. of Alaska, Anchorage, AK (United States)] [and others] [Univ. of Alaska, Anchorage, AK (United States); and others

1994-09-01

303

The origin of carbon monoxide in Neptunes's atmosphere  

NASA Technical Reports Server (NTRS)

The CO abundance in the observable atmosphere of Neptune can be plausibly explained by rapid vertical mixing from the deeper atmosphere if Neptune has a greater complement of water than Uranus. Thermochemical equilibrium and kinetic calculations reveal that Neptune must and Uranus may have about 10 times more oxygen than carbon, whereas for Jupiter and Saturn equal enrichments of carbon and oxygen are satifactory to explain the observed CO abundances by deep vertical mixing. Relative to hydrogen and solar composition, the respective enrichment factors for carbon and oxygen are 41, 440 (Neptune); 32, less than or equal 260 (Uranus); 6.6, 6.6 (Saturn); and 2.8, 2.8 (Jupiter). Because water ice is the most refractory ice among the ices assumed to be present in the outer solar nebula, the most massive H2O enrichment is expected for the outermost planet of this group. Thus, Neptune can indeed be regarded as the 'god of the seas.'

Lodders, K.; Fegley, B., Jr.

1994-01-01

304

The origin of carbon monoxide in Neptunes's atmosphere  

NASA Astrophysics Data System (ADS)

The CO abundance in the observable atmosphere of Neptune can be plausibly explained by rapid vertical mixing from the deeper atmosphere if Neptune has a greater complement of water than Uranus. Thermochemical equilibrium and kinetic calculations reveal that Neptune must and Uranus may have about 10 times more oxygen than carbon, whereas for Jupiter and Saturn equal enrichments of carbon and oxygen are satifactory to explain the observed CO abundances by deep vertical mixing. Relative to hydrogen and solar composition, the respective enrichment factors for carbon and oxygen are 41, 440 (Neptune); 32, less than or equal 260 (Uranus); 6.6, 6.6 (Saturn); and 2.8, 2.8 (Jupiter). Because water ice is the most refractory ice among the ices assumed to be present in the outer solar nebula, the most massive H2O enrichment is expected for the outermost planet of this group. Thus, Neptune can indeed be regarded as the 'god of the seas.'

Lodders, K.; Fegley, B., Jr.

1994-12-01

305

Critical review of carbon monoxide pressure measurements in the uranium carbon oxygen ternary system  

NASA Astrophysics Data System (ADS)

For high temperature reactors (HTR), the high level of fuel operating temperature in normal and accidental conditions requires to predict the possible chemical interactions between the fuel components. Among the concerns of the TRISO fuel particle thermomechanical behavior, it is necessary to better understand the carbon monoxide formation due to chemical interactions at the UO 2 kernel and graphite buffer's interface. In a first step, the thermodynamic properties of the U-C-O system have to be assessed. The experimental data from literature on the equilibrium CO gas pressure measurements in the UO 2-UC 2-C ternary section of the U-C-O system are critically reviewed. Discrepancies between the different determinations can be explained - (i) by the different gaseous flow regimes in the experiments and - (ii) by the location of the measuring pressure gauge away from the reaction site. Experimental values are corrected - (i) from the gaseous flow type (molecular, transition or viscous) defined by the Knudsen number and - (ii) from the thermomolecular effect due to the temperature gradient inside the experimental vessels. Taking account of the selected and corrected values improves greatly the consistency of the original set of measurements.

Gossé, S.; Guéneau, C.; Chatillon, C.; Chatain, S.

2006-06-01

306

Deactivation of iron catalysts in the hydrogenation of carbon monoxide  

Microsoft Academic Search

Two activation treatments have been applied to iron catalysts studied in the FT synthesis. Reduced catalysts or oxidized catalysts have their surface and bulk composition modified in different ways. In both cases the surface is covered by carbon and a fraction of it is directly involved in the FT reaction with H2 whereas the remainder is transformed into carbide not

J. P. Reymond; B. Pommier

1999-01-01

307

CARBON MONOXIDE FLUXES OF DIFFERENT SOIL LAYERS IN UPLAND CANADIAN BOREAL FORESTS  

EPA Science Inventory

Dark or low-light carbon monoxide fluxes at upland Canadian boreal forest sites were measured on-site with static chambers and with a laboratory incubation technique using cores from different depths at the same sites. Three different upland black spruce sites, burned in 1987,199...

308

Ice Core Data of Atmospheric Carbon Monoxide Over Antarctica During The Last 170 Years  

Microsoft Academic Search

The importance and interest for reconstructing past CO concentrations arises from its significant role on the chemistry of the troposphere. As the major sink for hydroxyl radicals (OH), carbon monoxide is considered to regulate the oxidative capacity of the atmosphere. CO also has a close link with methane which is a main source of CO especially in Southern Hemisphere. Past

Z. Wang; J. Mak; J. Chappellaz

2008-01-01

309

A positron emission tomography study of patients with acute carbon monoxide poisoning treated by hyperbaric oxygen  

Microsoft Academic Search

Seven patients with an acute and severe carbon monoxide intoxication were treated with hyperbaric oxygen and underwent a positron emission tomographic examination 2–5 days after the acute event. Although the final clinical outcome was good in all patients, ischaemic changes were observed. Three patients with temporary sequelae after hyperbaric oxygen treatment showed the most severe changes, mainly in striatum and

J. De Reuck; D. Decoo; I. Lemahieu; K. Strijckmans; P. Boon; G. Maele; W. Buylaert; D. Leys; H. Petit

1993-01-01

310

Quantitating carbon monoxide production from heme by vascular plant preparations in vitro  

Microsoft Academic Search

Heme in animals is mainly degraded enzymatically, producing a predictable amount of carbon monoxide (CO). Under some conditions, alternative sources of CO production are important, such as lipid peroxidation and photo-oxidation. Less is known about CO production in plants as a reflection of enzymatic activity or coupled oxidation, but a sensitive assay for CO production in plants would be a

Hendrik J. Vreman; Ronald J. Wong; David K. Stevenson

2011-01-01

311

The combined effect of heat and carbon monoxide on the performance of motorsport athletes  

Microsoft Academic Search

Two of the major stressors endured by a motorsport athlete (MSA) during a racing event are the effects of heat and carbon monoxide. To date, there has been little research into their combined effect on driving performance. Using an interactive racecar simulator located within an environmental chamber, subjects drove a simulated race (60 min) in environmental conditions similar to those

Scott M Walker; Timothy R Ackland; Brian Dawson

2001-01-01

312

Short-Term Effects of Carbon Monoxide on Mortality: An Analysis within the APHEA Project  

Microsoft Academic Search

OBJECTIVES: We investigated the short-term effects of carbon monoxide on total and cardiovascular mortality in 19 European cities participating in the APHEA-2 (Air Pollution and Health: A European Approach) project. METHODS: We examined the association using hierarchical models implemented in two stages. In the first stage, data from each city were analyzed separately, whereas in the second stage the city-

Evangelia Samoli; Giota Touloumi; Joel Schwartz; Hugh Ross Anderson; Christian Schindler; Bertil Forsberg; Maria Angela Vigotti; Judith Vonk; Mitja Košnik; Jiri Skorkovsky; Klea Katsouyanni

2007-01-01

313

Effects of carbon monoxide on myocardium. Ultrastructural changes in rabbits after moderate, chronic exposure  

Microsoft Academic Search

Exposure chamber experiments were conducted with 16 male albino rabbits to investigate the effects of carbon monoxide on myocardial ultrastructure. Half of the animals were exposed to 180 ppM of CO, while the other half were exposed to atmospheric air for 2 weeks. Local areas of partial or total necrosis of the myofibrils and degenerative changes of the mitochondria were

K. Kjeldsen; H. K. Thomsen; P. Astrup

1974-01-01

314

Method for producing reduction gases consisting essentially of carbon monoxide and hydrogen  

Microsoft Academic Search

A single heat method of producing reduction gases which consist essentially of carbon monoxide and hydrogen for ore-reducing processes, comprises, directing a coal and water suspension into a reactor to generate combustion gases under pressure having a temperature in the range of from 1300* C. To 1500* C. And mixing the combustion gases immediately after they are formed with reduction

Tippmer

1980-01-01

315

Tropospheric carbon monoxide and hydrogen measurements over Kalimantan in Indonesia and northern Australia during October, 1997  

Microsoft Academic Search

During the PACE-5 campaign over Australia and Indonesia in October 1997, we used an aircraft to measure carbon monoxide (CO) and hydrogen (H2). Latitudinal distributions of CO and H2 clearly showed a large increase from northern Australia to Kalimantan in Indonesia. Elevated CO levels over northern Australia were observed only in the smoke plumes of savanna fires. A thick smoke

Yousuke Sawa; Hidekazu Matsueda; Yukitomo Tsutsumi; Jørgen B. Jensen; Hisayuki Y. Inoue; Yukio Makino

1999-01-01

316

Connections between Concepts Revealed by the Electronic Structure of Carbon Monoxide  

ERIC Educational Resources Information Center

Different models for the electronic structure of carbon monoxide are suggested in influential textbooks. Therefore, this electronic structure offers an interesting subject in teaching because it can be used as an example to relate seemingly conflicting concepts. Understanding the connections between ostensibly different methods and between…

Liu, Ying; Liu, Bihui; Liu, Yue; Drew, Michael G. B.

2012-01-01

317

Carbon monoxide in indoor ice skating rinks: Evaluation of absorption by adult hockey players  

Microsoft Academic Search

We evaluated alveolar carbon monoxide (CO) levels of 122 male, adult hockey players active in recreational leagues of the Quebec City region (Canada), before and after 10 weekly 90-minute games in 10 different rinks. We also determined exposure by quantifying the average CO level in the rink during the games. Other variables documented included age, pulmonary function, aerobic capacity, and

B. Levesque; E. Dewailly; R. Lavoie; D. PrudHomme; S. Allaire

1990-01-01

318

Carbon Monoxide and Methane Production in Rats, Guinea Pigs, and Germ-Free Rats.  

National Technical Information Service (NTIS)

A closed rebreathing system was devised to measure trace gas production by individual animals. The apparatus was used to measure the production of carbon monoxide and methane by normal control rats and guinea pigs and by germ-free rats. Total body hemoglo...

F. L. Rodkey H. A. Collison J. D. O'Neal

1971-01-01

319

Standardising analysis of carbon monoxide rebreathing for application in anti-doping  

Microsoft Academic Search

Determination of total haemoglobin mass (Hbmass) via carbon monoxide (CO) depends critically on repeatable measurement of percent carboxyhaemoglobin (%HbCO) in blood with a hemoximeter. The main aim of this study was to determine, for an OSM3 hemoximeter, the number of replicate measures as well as the theoretical change in percent carboxyhaemoglobin required to yield a random error of analysis (Analyser

Anthony C. Alexander; Laura A. Garvican; Caroline M. Burge; Sally A. Clark; James S. Plowman; Christopher J. Gore

2011-01-01

320

COMPUTATIONAL ANALYSES OF THE UPTAKE AND DISTRIBUTION OF CARBON MONOXIDE (CO) IN HUMAN SUBJECTS  

Microsoft Academic Search

Carbon monoxide (CO) is an odorless, colorless, tasteless gas that binds to hemoglobin with high affinity. This property underlies the use of low doses of CO to determine hemoglobin mass (MHb) in the fields of clinical and sports medicine. However, hemoglobin bound to CO is unable to transport oxygen and exposure to high CO concentrations is a significant environmental and

Kinnera Chada

2011-01-01

321

Carbon Monoxide Production from Sevoflurane Breakdown: Modeling of Exposures Under Clinical Conditions  

Microsoft Academic Search

Isoflurane, enflurane, sevoflurane, and especially des- flurane produce carbon monoxide (CO) during reaction with desiccated absorbents. Of these, sevoflurane is the least studied. We investigated the dependence of CO production from sevoflurane on absorbent tempera- ture, minute ventilation (Ve), and fresh gas flow rates. We measured absorbent temperature and in vitro CO concentrations when desiccated Baralyme reacted with 1 minimum

STEVEN J. BARKER

322

Reaction engineering for materials processing in space: Reduction of ilmenite by hydrogen and carbon monoxide  

NASA Technical Reports Server (NTRS)

Oxygen is a consumable material which needs to be produced continuously in most space missions. Its use for propulsion as well as life support makes oxygen one of the largest volume chemicals to be produced in space. Production of oxygen from lunar materials is of particular interest and is very attractive possibility. The kinetics and mechanism of reduction of ilmenite by carbon monoxide and hydrogen at 800 to 1100 C were investigated. The temporal profiles of conversion for carbon monoxide have a sigmoidal shape and indicate the presence of three different stages (induction, acceleration, and deceleration) during the reduction reaction. The apparent activation energy decreases from 18 kcal/mole at 10 percent conversion to 10 kcal/mole at 50 percent conversion. The reaction is first order with respect to carbon monoxide under the experimental conditions studied. Both SEM and EDX analysis show that the diffusion of Fe product away from the reaction front and through the TiO2 phase, followed by the nucleation and growth of a separate Fe phase are important steps affecting the process kinetics. The results from hydrogen reduction show that the mechanism of ilmenite reduction by hydrogen is similar to that by carbon monoxide. However, the titanium dioxide can be further reduced by hydrogen at 800 to 1000 C. The detailed comparison and theoretical modeling of both reduction processes is presented.

Zhao, Y.; Shadman, F.

1991-01-01

323

Effects of Short-Term Low Level Carbon Monoxide Exposure on Human Performance.  

National Technical Information Service (NTIS)

The effects of 0, 50, 125, 200, and 250 ppm of carbon monoxide exposure on human time estimation, tracking, ataxia, galvanic skin response and heart rate were tested in 10 subjects. Mean carboxyhemoglobin levels from .96 to 12.37% were reached after 3 hou...

J. Theodore P. Heinig P. Mikulka R. D. O'Donnell

1970-01-01

324

Use of a One-man, Mobile Pressure Chamber in the Treatment of Carbon Monoxide Poisoning  

PubMed Central

For the past five years a mobile pressure chamber has been used to treat patients suffering from severe carbon monoxide poisoning with oxygen at 2 atmospheres pressure. Of the 25 patients treated, 20 recovered completely and only three died. This apparatus could also be used for hyperbaric oxygen therapy in other conditions for which it is indicated. Imagesp334-a

Norman, J. N.; MacIntyre, J.; Shearer, J. R.; Smith, G.

1970-01-01

325

Carbon Monoxide Reversibly Alters Iron Homeostasis and Respiratory Epithelial Cell Function  

Microsoft Academic Search

The dissociation of iron from heme is a major factor in iron metab- olism and the cellular concentrations of the metal correlate with heme degradation. We tested the hypotheses that (1) exposure to a product of heme catabolism, carbon monoxide (CO), alters iron homeostasis in the lung and in cultured respiratory epithelial cells; (2) this response includes both decreased uptake

Andrew J. Ghio; Jacqueline G. Stonehuerner; Lisa A. Dailey; Judy H. Richards; Michael D. Madden; Zhongping Deng; N.-B. Nguyen; Kimberly D. Callaghan; Funmei Yang; Claude A. Piantadosi

2008-01-01

326

Effect of non-nicotine cigarettes and carbon monoxide on angina.  

PubMed

The effect of smoking five non-nicotine cigarettes and of breathing carbon monoxide on exercise-induced angina was evaluated in 12 patients with angina. Smoking increased venous carboxyhemoglobin from 1.71 to 5.35%, decreased exercise duration until angina 45%, increased ischemic ST-segment depression at angina from 1.33 to 1.52 mm, and decreased systolic blood pressure times heart rate at angina. Breathing carbon monoxide increased venous carboxyhemoglobin from 1.73 to 5.37%, decreased exercise duration until angina 35%, increased ischemic ST-segment depression at angina from 1.31 to 1.50 mm, and decreased systolic blood pressure times heart rate at angina. Greater decreases in exercise duration until angina and in systolic blood pressure times heart rate at angina (p less than 0.001) were observed after smoking than after breathing carbon monoxide. Tobacco components other than nicotine or carbon monoxide are responsible for a small decrease in exercise performance until angina. PMID:7351051

Aronow, W S

1980-02-01

327

Application of the urban airshed model for carbon monoxide (CO) in Phoenix, Arizona  

Microsoft Academic Search

This paper presents an overview of an application of the urban airshed model (UAM) to the study of carbon monoxide (CO) in the Phoenix metropolitan area. The UAM is the EPA-approved and preferred grid model for urban ozone applications, and has recently been applied to the study of CO in urban areas such as Denver. The Phoenix metropolitan area is

J. L. Haney; R. G. Ireson

1988-01-01

328

FINAL SAMPLING REPORT FOR THE STUDY OF PERSONAL CO (CARBON MONOXIDE) EXPOSURE  

EPA Science Inventory

This report describes the sample selection procedures used for a study funded by the EPA and conducted by the Research Triangle Institute in 1982 and 1983 to evaluate methodology for collecting data on personal exposure to carbon monoxide (CO). These data were collected in the me...

329

Predicting Exposure Conditions that Facilitate the Potentiation of Noise-Induced Hearing Loss by Carbon Monoxide  

Microsoft Academic Search

Hearing loss is the most common occupational disease in the United States, with noise serving as the presumed causative agent in most instances. This investigation characterizes the exposure conditions that facilitate the potentiation of noise-induced hearing loss (NIHL) by carbon monoxide (CO). Auditory function was compared in rats exposed 4 weeks earlier to noise alone, CO alone, combined exposure, and

Laurence D. Fechter; Guang-Di Chen; Deepa Rao; Jason Larabee

2000-01-01

330

Pits confined in ultrathin cerium(IV) oxide for studying catalytic centers in carbon monoxide oxidation  

NASA Astrophysics Data System (ADS)

Finding ideal material models for studying the role of catalytic active sites remains a great challenge. Here we propose pits confined in an atomically thin sheet as a platform to evaluate carbon monoxide catalytic oxidation at various sites. The artificial three-atomic-layer thin cerium(IV) oxide sheet with approximately 20% pits occupancy possesses abundant pit-surrounding cerium sites having average coordination numbers of 4.6 as revealed by X-ray absorption spectroscopy. Density-functional calculations disclose that the four- and five-fold coordinated pit-surrounding cerium sites assume their respective role in carbon monoxide adsorption and oxygen activation, which lowers the activation barrier and avoids catalytic poisoning. Moreover, the presence of coordination-unsaturated cerium sites increases the carrier density and facilitates carbon monoxide diffusion along the two-dimensional conducting channels of surface pits. The atomically thin sheet with surface-confined pits exhibits lower apparent activation energy than the bulk material (61.7 versus 122.9?kJ?mol-1), leading to reduced conversion temperature and enhanced carbon monoxide catalytic ability.

Sun, Yongfu; Liu, Qinghua; Gao, Shan; Cheng, Hao; Lei, Fengcai; Sun, Zhihu; Jiang, Yong; Su, Haibin; Wei, Shiqiang; Xie, Yi

2013-11-01

331

Neuropsychologic and Functional Recovery From Severe Carbon Monoxide Poisoning Without Hyperbaric Oxygen Therapy  

Microsoft Academic Search

Study objective: To test the hypothesis that neuropsychologic test results and functional outcome will be abnormal if hyperbaric oxygen (HBO) is not used in patients with severe carbon monoxide (CO) poisoning. Methods: For a 1-year interval, we retrospectively identified all CO-poisoned patients who were comatose on presentation at a large, urban tertiary hospital and did not receive HBO therapy. Prospectively,

Lindell K Weaver; Ramona O Hopkins; Valerie Larson-Lohr

1996-01-01

332

Enhanced field ionization of water adsorbed on a carbon monoxide-covered, platinum field emitter tip  

Microsoft Academic Search

The influence of carbon monoxide, adsorbed on a platinum field emitter tip, on field ionization of adsorbed water was examined. Ramped field desorption (RFD) measurements of water ionization were performed at 108K for water layer thicknesses up to 80ML on a clean or CO-saturated tip surface. In RFD the applied field is ramped linearly in time until water ionization is

R. Manghani; E. M. Stuve

2009-01-01

333

Effects of Exposure to Low-Level Carbon Monoxide at High Altitude in Sensitive Subjects.  

National Technical Information Service (NTIS)

The study involved acute exposures of 18 male non-smokers to air with 100 ppm carbon monoxide (CO) or clean air under sea level and simulated high altitude (2.1 km). The subjects had physician-diagnosed ischemic heart disease and stable angina and were no...

M. T. Kleinman D. Leaf

1991-01-01

334

Remote sensing of global fire patterns, aerosol optical thickness, and carbon monoxide during April 1994  

Microsoft Academic Search

The current study examines global fire patterns, aerosol optical thickness (AOT) and carbon monoxide concentrations during April 9-19, 1994. Recently, global Advanced Very High Resolution Radiometer (AVHRR) data at nadir ground spatial resolution of 1 km are made available through the NASANOAA Pathfinder project. These data from April 9-19, 1994 are used to map fires over the Earth. Daytime data

S. A. Christopher; Min Wang; Donna V. Kliche; Ronald M. Welch; S. Nolf; V. S. Connors

1997-01-01

335

Carbon monoxide-related deaths in a metropolitan county in the USA: an 11-year study  

Microsoft Academic Search

Carbon monoxide (CO) poisoning as a cause of death is well documented in industrialized countries. The objective of this study was to compare demographic data in deaths due to accidents (in fires) and suicides in the same population between 1988 and 1998. Furthermore, the potential effect of a community wide education effort regarding safety in the home was assessed. Postmortem

Cynthia D. Homer; David A. Engelhart; Eric S. Lavins; Amanda J. Jenkins

2005-01-01

336

Emergency department visits for carbon monoxide poisoning in the Pacific Northwest  

Microsoft Academic Search

This study was conducted to determine the annual number of emergency department (ED) visits and rate of hyperbaric oxygen (HBO2) treatment for carbon monoxide (CO) poisoning in Washington, Idaho, and Montana. All hospital emergency departments and hyperbaric treatment facilities in the region were surveyed by mail and telephone regarding their patient treatment experience for calendar year 1994. Results demonstrated that

Neil B Hampson

1998-01-01

337

Role of Carbon Monoxide and Biliverdin in Renal Ischemia\\/Reperfusion Injury  

Microsoft Academic Search

Heme oxygenase (HO) isoforms catalyze the conversion of heme to carbon monoxide (CO) and biliverdin\\/bilirubin with a concurrent release of iron. There is strong evidence that HO activity and products play a major role in renoprotection, however the exact molecular mechanisms underlying the beneficial effects exerted by this pathway are not fully understood. This review is aimed at illustrating the

G. Li Volti; L. F. Rodella; C. Di Giacomo; R. Rezzani; R. Bianchi; E. Borsani; D. Gazzolo; R. Motterlini

2006-01-01

338

[Suicidal carbon monoxide poisoning in an electric car. An unusual case report].  

PubMed

The authors report a case of a man who committed suicide by poisoning with carbon monoxide in his electric vehicle. He applied a small motor generator with no exhaust normally used for charging the vehicle's batteries at home, that was found on the loading space behind the seat. This demonstrates the value of a thorough scene investigation. PMID:7832611

Bohnert, M; Zollinger, U

1994-01-01

339

PREDICTION OF CARBOXYHEMOGLOBIN FORMATION DUE TO TRANSIENT EXPOSURE TO CARBON MONOXIDE  

EPA Science Inventory

Prediction of carboxyhemoglobin formation due to transient xposure to carbon monoxide. . Appl. Physiol. 76(4):1739-1745, 1994.-Fifteen men were exposed to 6,683 ppm C18O for 3.09-6.65 min. rterial and antecubital vein blood samples were drawn at 1-min intervals beginning at the s...

340

[Case of carbon monoxide poisoning with delayed encephalopathy assessed by magnetic resonance imaging].  

PubMed

A 21-year-old man attempted suicide by burning charcoal in a car for more than one day and was admitted to a regional hospital. On admission, his blood carboxyhemoglobin concentration was 4.4%. The patient was transferred to our emergency department because of suspected carbon monoxide poisoning. Hyperbaric oxygen therapy (HBO) was performed 5 times over 3 days. Fluid-attenuation inversion recovery (FLAIR) and diffusion-weighted (DWI) magnetic resonance imaging (MRI) performed on day 3 showed high signal-intensity lesions in the cerebral white matter. Additional HBO was performed once per day until day 16. Wecheler Memory Scale-Reviced (WMS-R) and Mini-Mental State Examination (MMSE) performed on day 17 showed his cognitive impairment. He gradually recovered the cognitive function and was discharged from the hospital without neurological sequelae on day 49. Delayed encephalopathy after acute carbon monoxide poisoning with dementia, mental impairment, and psychosis is a serious complication. Hyperintensity in FLAIR and DWI MRI predicts delayed encephalopathy and indicates cellular edema and demyelination of the white matter. One of the risk factors is prolonged carbon monoxide exposure. This case suggests that the patient, who was exposed to carbon monoxide for many hours, was at a high risk of delayed encephalopathy despite the low blood carboxyhemoglobin concentration and therefore must be monitored using MRI. PMID:23600269

Seino, Keiko; Hayashida, Akiko; Iseki, Ken

2013-03-01

341

Operational carbon monoxide retrieval algorithm and selected results for the MOPITT instrument  

Microsoft Academic Search

Measurements of Pollution in the Troposphere (MOPITT) is a new remote sensing instrument aboard the Earth Observing System (EOS) “Terra” satellite which exploits gas correlation radiometry principles to quantify tropospheric concentrations of carbon monoxide (CO) and methane (CH4). The MOPITT CO retrieval algorithm employs a nonlinear optimal estimation method to iteratively solve for the CO profile which is statistically most

M. N. Deeter; L. K. Emmons; G. L. Francis; D. P. Edwards; J. C. Gille; J. X. Warner; B. Khattatov; D. Ziskin; J.-F. Lamarque; S.-P. Ho; V. Yudin; J.-L. Attié; D. Packman; J. Chen; D. Mao; James R. Drummond

2003-01-01

342

CARBON MONOXIDE REVERSIBLY DISRUPTS IRON HOMEOSTATIS AND RESPIRATORY EPITHELIAL CELLS FUNCTION  

EPA Science Inventory

Iron dissociation from heme is a major factor in iron metabolism and cellular concentrations of the metal correlate inversely with the expression of heme oxygenase (HO). We tested the hypothesis that 1) exposure to a product of HO, carbon monoxide (CO), disturbs iron homeostas...

343

METHODOLOGY FOR DESIGNING AIR QUALITY MONITORING NETWORKS: 2. APPLICATION TO LAS VEGAS, NEVADA, FOR CARBON MONOXIDE  

EPA Science Inventory

An objective methodology presented in a companion paper (Liu et al., 1986) for determining the optimum number and disposition of ambient air quality stations in a monitoring network for carbon monoxide is applied to the Las Vegas, Nevada, area. The methodology utilizes an air qua...

344

Evaluation of Length-of-Stain Gas Indicator Tubes for Measuring Carbon Monoxide in Air.  

ERIC Educational Resources Information Center

Techniques for detection and measurement of carbon monoxide (CO) in air are of interest and utility in many aspects of automotive safety. CO concentrations may range from less than 100 parts per million (ppm), or 0.01 percent, to about 10 percent by volume. Gas indicator tubes have been used for many years primarily as detectors of hazardous gases…

Klaubert, Earl C.; And Others

345

LOW-LEVEL CARBON MONOXIDE EXPOSURE AND WORK CAPACITY AT 1600 METERS  

EPA Science Inventory

At sea level, low-level carbon monoxide (CO) exposure impairs exercise performance. To determine if altitude residence at 1600 m augments this CO effect, two studies of graded treadmill work capacity were done. The Initial Study investigated nine, non-smoking male subjects breath...

346

SEASONAL SOIL FLUXES OF CARBON MONOXIDE IN BURNED AND UNBURNED BRAZILIAN SAVANNAS  

EPA Science Inventory

Soil-atmosphere fluxes of carbon monoxide (CO) were measured from September 1999 through November 2000 in savanna areas in central Brazil (Cerrado) under different fire regimes using transparent and opaque static chambers. Studies focused on two vegetation types, cerrado stricto...

347

Noble metal catalysts for the preferential oxidation of carbon monoxide in the presence of hydrogen (PROX)  

Microsoft Academic Search

Oxide-supported noble metal catalysts were tested in the preferential oxidation of carbon monoxide (PROX) reaction in the temperature range between 50 and 300°C. Both the influence of the noble metal nature (Pt, Ir, Pd), the support physical and chemical properties (redox, acidity, basicity) and the reaction conditions (oxygen stoichiometry) on the catalyst activity and selectivity was evaluated. Platinum and iridium

Fernando Mariño; Claude Descorme; Daniel Duprez

2004-01-01

348

Reducing the Risk of Accidental Death Due to Vehicle-Related Carbon Monoxide Poisoning  

Microsoft Academic Search

Emissions of carbon monoxide (CO) from motor vehicles cause several hundred accidental fatal poisonings annually in the United States. The circumstances that could lead to fatal poisonings in residential settings with motor vehicles as the source of CO were explored. The risk of death in a garage (volume = 90 m) and a single-family dwelling (400 m) was evaluated using

Linsey C. Marr; Glenn C. Morrison; William W. Nazaroff; Robert A. Harley

1998-01-01

349

In-vehicle Exposure to Carbon Monoxide Emissions from Vehicular Exhaust: A Critical Review  

Microsoft Academic Search

Vehicle-induced emissions constitute a major source of air pollutants, particularly in urban areas, where heavy traffic is common occurrence. Contaminated air can flow into enclosed micro-environments, including vehicle compartments. Among various exhaust emissions, carbon monoxide (CO) was the first indicator examined in passenger compartments. This paper presents a critical review of worldwide research work conducted to characterize CO exposure inside

M. El-Fadel; L. Abi-Esber

2009-01-01

350

Double Auger Emission of fixed-in-space Carbon Monoxide following Core-Excitation and Ionization  

NASA Astrophysics Data System (ADS)

Double Auger decay after core-level photo excitation and after ionization through synchrotron radiation in gas phase carbon monoxide has been studied. We report the first experiment where both Auger electrons in double Auger decay have been measured in coincidence with the ionic fragments.

Trinter, F.; Schöffler, M. S.; Jahnke, T.; Bocharova, I. A.; Vredenborg, A.; Guillemin, R.; Sturm, F. P.; Neumann, N.; Cole, K.; Williams, J. B.; Simon, M.; Landers, A.; Weber, T.; Dörner, R.

2012-11-01

351

Observations of Carbon Monoxide and Aerosol From the Terra Satellite: Northern Hemisphere Variability  

Microsoft Academic Search

Measurements from the Terra satellite launched in December of 1999 now provide a global record of the recent inter-annual variability of tropospheric air quality: carbon monoxide (CO) from the Measurement Of Pollution In The Troposphere (MOPITT) instrument, and of aerosol optical depth (AOD) from the Moderate-resolution Imaging Spectroradiometer (MODIS). This paper compares and contrasts these data sets with a view

D. P. Edwards; L. K. Emmons; D. A. Hauglustaine; D. A. Chu; J. C. Gille; Y. J. Kaufman; G. Petron; L. N. Yurganov; J. Drummond; M. N. Deeter; V. Yudin; D. C. Ziskin; J. Warner; J.-F. Lamarque; G. L. Francis; S. P. Ho; D. Mao; J. Chen; E. I. Grechko

2004-01-01

352

CRITICAL HEALTH ISSUES ASSOCIATED WITH REVIEW OF THE SCIENTIFIC CRITERIA FOR CARBON MONOXIDE  

EPA Science Inventory

The Clean Air Act (CAA) requires periodic review of existing criteria that form the basis for carbon monoxide (CO) air quality standards. These air quality criteria are to reflect the latest scientific information useful in indicating the kind and extent of all identifiable effec...

353

Chronic carbon monoxide poisoning resulting in bilateral cataracts and a cystic globus pallidus lesion  

PubMed Central

The authors describe a case of a 43-year-old lady who developed bilateral cataracts, seizures and a unilateral cystic lesion of the basal ganglia following low-dose carbon monoxide (CO) exposure over 7 years. Cataract formation may result from sustained oxidative stress as a result of chronic environmental CO exposure.

Kasbekar, Shivani; Gonzalez-Martin, Jose Argelio

2011-01-01

354

Chronic carbon monoxide poisoning resulting in bilateral cataracts and a cystic globus pallidus lesion.  

PubMed

The authors describe a case of a 43-year-old lady who developed bilateral cataracts, seizures and a unilateral cystic lesion of the basal ganglia following low-dose carbon monoxide (CO) exposure over 7 years. Cataract formation may result from sustained oxidative stress as a result of chronic environmental CO exposure. PMID:22689549

Kasbekar, Shivani; Gonzalez-Martin, Jose Argelio

2011-01-01

355

Carbon Monoxide In-Flight Incapacitation: An Occasional Toxic Problem in Aviation.  

National Technical Information Service (NTIS)

Results from the toxicological study of samples from 4,072 pilots killed in general aviation accidents have revealed that carbon monoxide has been the cause of incapacitation in 21 (0.5 percent) of the cases. Two cases are presented that are typical of ac...

D. J. Lacefield P. A. Roberts P. M. Grape

1982-01-01

356

Low-Level Carbon Monoxide Exposure and Work Capacity at 1600 Meters.  

National Technical Information Service (NTIS)

At sea level, low-level carbon monoxide (CO) exposure impairs exercise performance. To determine if altitude residence at 1600 m augments this CO effect, two studies of graded treadmill work capacity were done. The Initial Study investigated nine, non-smo...

P. C. Weiser G. J. A. Cropp C. G. Morrill T. L. Kurt D. W. Dickey

1979-01-01

357

EDUCATION LEVEL IS GREATEST RISK-FACTOR IN CARBON MONOXIDE POISONING  

EPA Science Inventory

Carbon monoxide (CO) is a toxic by-product of the combustion of fossil fuels. In confined spaces, inefficient combustion sources, such as furnaces, stoves, kerosene heaters and automobiles can generate levels of CO that interrupt oxygen transport throughout the body, potentially ...

358

Measuring Oxygen, Carbon Monoxide and Hydrogen Sulfide Diffusion Coefficient and Solubility in Nafion Membranes  

Microsoft Academic Search

A Devanathan-Stachurski type diffusion cell made from a fuel cell assembly is designed to evaluate the gas transport properties of a proton exchange membrane as a function of cell temperature and gas pressure. Data obtained on this cell using the electrochemical monitoring technique (EMT) is used to estimate solubility and diffusion coefficient of oxygen (O2), carbon monoxide (CO) and hydrogen

Vijay A. Sethuraman; Saahir Khan; Jesse S. Jur; Andrew T. Haug; John W. Weidner

2011-01-01

359

Measuring oxygen, carbon monoxide and hydrogen sulfide diffusion coefficient and solubility in Nafion membranes  

Microsoft Academic Search

A Devanathan–Stachurski type diffusion cell made from a fuel cell assembly is designed to evaluate the gas transport properties of a proton exchange membrane as a function of cell temperature and gas pressure. Data obtained on this cell using the electrochemical monitoring technique (EMT) is used to estimate solubility and diffusion coefficient of oxygen (O2), carbon monoxide (CO) and hydrogen

Vijay A. Sethuraman; Saahir Khan; Jesse S. Jur; Andrew T. Haug; John W. Weidner

2009-01-01

360

Modeling the diurnal cycle of carbon monoxide: Sensitivity to physics, chemistry, biology, and optics  

Microsoft Academic Search

As carbon monoxide within the oceanic surface layer is produced by solar radiation, diluted by mixing, consumed by biota, and outgassed to the atmosphere, it exhibits a diurnal cycle. The effect of dilution and mixing on this cycle is examined using a simple model for production and consumption coupled to three different mixed layer models. The magnitude and timing of

Anand Gnanadesikan

1996-01-01

361

Photobiogeochemical cycling of carbon monoxide in the southeastern Beaufort Sea in spring and autumn  

Microsoft Academic Search

We investigated the distribution, photoproduction, microbial uptake, and air-sea exchange of carbon monoxide (CO), a key photoproduct of chromophoric dissolved organic matter (CDOM), in open waters of the southeastern Beaufort Sea in autumn 2003 and spring 2004. Diurnal cycles of surface water CO concentration ((CO)) occurred in autumn but not in spring. In both seasons (CO) was well above air-equilibrium

Huixiang Xie; Simon Belanger; Serge Demers; Warwick F. Vincent; Tim N. Papakyriakou

2009-01-01

362

Diurnal cycling of carbon monoxide (CO) in the upper ocean near Bermuda  

Microsoft Academic Search

A coupled photochemical–physical model for the upper ocean carbon monoxide concentration is presented. The coupled model uses a spectral optical model and a number of different mixing parameterizations. It is run using the meteorological forcing conditions measured during a 9-day investigation near Bermuda in the Sargasso Sea in March 1993 in the declining phase of the spring bloom. The baseline

A. James Kettle

2005-01-01

363

Daily global maps of carbon monoxide from NASA's Atmospheric Infrared Sounder  

Microsoft Academic Search

We present the first observations of tropospheric carbon monoxide (CO) by the Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua satellite. AIRS daily coverage of ~70% of the planet represents a significant evolutionary advance in satellite trace gas remote sensing. Tropospheric CO abundances are retrieved from AIRS 4.55 mum spectral region using the full AIRS retrieval algorithm run in a research

W. W. McMillan; C. Barnet; L. Strow; M. T. Chahine; M. L. McCourt; J. X. Warner; P. C. Novelli; S. Korontzi; E. S. Maddy; S. Datta

2005-01-01

364

CARBON MONOXIDE EXPOSURES INSIDE AN AUTOMOBILE TRAVELING ON AN URBAN ARTERIAL HIGHWAY  

EPA Science Inventory

Carbon monoxide (CO) exposures were measured inside a motor vehicle during 88 standardized drives on a major urban arterial highway, El Camino Real (traffic volume of 30,500-45,000 vehicles per day), over a 13-1/2 month period. n each trip (lasting between 31 and 61 minutes), the...

365

Fatality Assessment and Control Evaluation (FACE) for Wisconsin: Youth Camp Counselor Dies of Carbon Monoxide Poisoning.  

National Technical Information Service (NTIS)

A 15-year-old male camp counselor (the victim) died of carbon monoxide poisoning when the furnace malfunctioned in the cabin where he was sleeping. The victim had worked as a counselor at the camp for nine weeks, then planned to stay an extra week after t...

2001-01-01

366

Development and application of lightweight instruments for vertical profiling of ozone and carbon monoxide  

NASA Astrophysics Data System (ADS)

This thesis covers the development of low cost, lightweight instrumentation for vertical profiling measurements of ozone and carbon monoxide in the troposphere. These instruments are designed to fly on small, low-payload airborne platforms such as tethered kites and blimps. Thus, they can be used for making measurements from light aircraft as well. Due to their small size and low cost, they are also suitable for use as disposable sondes on released balloons or in dropsondes. The design and test results of a simple single-beam ultraviolet photometer for ozone measurements are presented. A novel airflow system and advanced electronics are among the most important changes from earlier reported systems. The current version of the instrument fits into a package 8 x 8 x 40 cm, weighs under 0.5 kg, and consumes approximately 8 watts of power. Independent measurements of ozone are made every six seconds, with a sensitivity of 0.3 ppbv ozone and a precision of 2%. The design and test results of a simple carbon monoxide detector based on the reducing gas detector principle are also presented. It operates by reacting carbon monoxide with mercuric oxide to produce mercury vapor, which may then be measured via ultraviolet absorption to compute the concentration of carbon monoxide. This instrument has several features which distinguish it from similar carbon monoxide analyzers, all of which contribute to its usefulness on small airborne platforms. It fits a package 10 x 20 x 25 cm, has a mass of 2.0 kg, and consumes an average of 20 watts of power. An independent measurement of carbon monoxide is made every eight seconds, with a sensitivity of 3 ppbv carbon monoxide and a precision of 4%. The packages these instruments are flown in are described, and other associated instruments in the packages are briefly covered. Two major packages are described: one for kites and blimps, and the other for light aircraft. These packages, while having a similar design architecture, have some significant differences regarding the suite of instruments carried in each. Finally, the theory of the extreme miniaturization of instruments such as those developed in this thesis will be discussed. Issues relevant to the miniaturization of instruments will be covered, and a case study proposing an ozone microsonde will be presented.

Bognar, John Andrew

1998-09-01

367

Studies relevant to the catalytic activation of carbon monoxide. Technical progress report, September 1991  

SciTech Connect

Research activity during the 1991--1992 funding period has been concerned with the following topics relevant to carbon monoxide activation. (1) Exploratory studies of water gas shift catalysts heterogenized on polystyrene based polymers. (2) Mechanistic investigation of the nucleophilic activation of CO in metal carbonyl clusters. (3) Application of fast reaction techniques to prepare and to investigate reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and to the formation of carbon-carbon bonds via the migratory insertion of CO into metal alkyl bonds.

Ford, P.C.

1992-06-04

368

Carbon Monoxide as an Electron Donor for the Biological Reduction of Sulphate  

PubMed Central

Several strains of Gram-negative and Gram-positive sulphate-reducing bacteria (SRB) are able to use carbon monoxide (CO) as a carbon source and electron donor for biological sulphate reduction. These strains exhibit variable resistance to CO toxicity. The most resistant SRB can grow and use CO as an electron donor at concentrations up to 100%, whereas others are already severely inhibited at CO concentrations as low as 1-2%. Here, the utilization, inhibition characteristics, and enzymology of CO metabolism as well as the current state of genomics of CO-oxidizing SRB are reviewed. Carboxydotrophic sulphate-reducing bacteria can be applied for biological sulphate reduction with synthesis gas (a mixture of hydrogen and carbon monoxide) as an electron donor.

Parshina, Sofiya N.; Sipma, Jan; Henstra, Anne Meint; Stams, Alfons J. M.

2010-01-01

369

The remote measurement of trace atmospheric species by correlation interferometry. I - Carbon monoxide and methane  

NASA Technical Reports Server (NTRS)

A correlation interferometer has been developed for the measurement of carbon monoxide and methane at 2.35 micrometers in the troposphere and in the stratosphere. This instrument has been tested in laboratory tests, solar-looking outdoor tests, and downward-looking airplane-based tests. The aircraft tests were flown on a Falcon fanjet provided by The Canada Centre for Remote Sensing over both polluted and unpolluted regions of North America. The results of these various tests are discussed. Based on the results obtained for carbon monoxide and methane, a study was undertaken to investigate the feasibility of measuring other atmospheric trace species by correlation interferometry. Results of the feasibility study for carbon dioxide, water vapor, ammonia, nitrous oxide, nitric oxide, nitrogen dioxide, sulfur dioxide, and several hydrocarbons are presented.

Goldstein, H. W.; Bortner, M. H.; Grenda, R. N.; Karger, A. M.; Dick, R.; David, F.; Lebel, P. J.

1973-01-01

370

Partial oxidation of methane, methanol, and mixtures of methane and methanol, methane and ethane, and methane, carbon dioxide, and carbon monoxide  

SciTech Connect

The homogeneous partial oxidation of methane involves the primary reactions of methane oxidation as well as the secondary reactions with the reaction products formaldehyde, methanol, and carbon monoxide. The complex free-radical set of reactions are modeled using a pseudo-first-order reaction parallel-series network of the three reactions: methane to methanol, methane to carbon monoxide, and methanol to carbon monoxide. The secondary reaction of methanol to carbon monoxide increases as the oxygen concentration in the feed increases. For experiments with 100% oxygen conversions, increases in residence time and temperature result in further loss of methane and methanol to CO. For temperatures greater than 710K some oxidative coupling occurs to produce ethane. The selectivity of methanol was 34-55% for feeds of 2.3-4.4% oxygen and 95-98% methane and 50 atm. The selectivity was highest at low conversions and low oxygen feed concentrations.

Chun, Jinwoo; Anthony, R.G. (Texas A and M Univ., College Station (United States))

1993-05-01

371

Photochemical production and microbial consumption of carbon monoxide in the Caribbean Sea as influenced by the Orinoco River  

SciTech Connect

Carbon monoxide is an important trace gas in the surface waters of the marine environment. An understanding of the mechanisms by which this gas is produced and consumed is important to our understanding carbon cycling in the world's oceans. Carbon monoxide is produced by photochemical processes involving dissolved organic material (DOM) and consumed by microorganism. Major rivers greatly influence the DOM content of the oceans. The Orinoco River of Venezuela inputs its waters into the Caribbean Sea and can, thus, influence production and consumption of carbon monoxide. Microbial consumption rates and photoproduction capacity for carbon monoxide were determined along 2 Caribbean cruise tracks during the spring (low river flow) and fall (high river flow) of 1988. Carbon monoxide production capacity was highest during the fall and the Orinoco influenced a greater area of the Caribbean than during the spring. The highest production capacity was observed in the waters of 22 ppt salinity during the fall and 6.5 ppt during the spring. Correlation of microbial consumption with the highest consumption rate occurring in waters with the highest production capacity. Turnover times for carbon monoxide were as low as 2.2 h, indicating the importance of microbial consumption in these waters.

Jones, R.D. (Florida International Univ., Miami (United States))

1990-01-09

372

Cobalt monoxide-doped porous graphitic carbon microspheres for supercapacitor application.  

PubMed

A novel design and facile synthesis process for carbon based hybrid materials, i.e., cobalt monoxide (CoO)-doped graphitic porous carbon microspheres (Co-GPCMs), have been developed. With the synthesis strategy, the mixture of cobalt gluconate, ?-cyclodextrin and poly (ethylene oxide)???-poly (propylene oxide)??-poly (ethylene oxide)??? is treated hydrothermally, followed by pyrolysis in argon. The resultant Co-GPCMs exhibits a porous carbon matrix with localized graphitic structure while CoO nanodots are embedded in the carbon frame. Thus, the Co-GPCMs effectively combine the electric double-layer capacitance and pseudo-capacitance when used as the electrode in supercapacitor, which lead to a higher operation voltage (1.6?V) and give rise to a significantly higher energy density. This study provides a new research strategy for electrode materials in high energy density supercapacitors. PMID:24113335

Yang, Zheng-Chun; Tang, Chun-Hua; Zhang, Yu; Gong, Hao; Li, Xu; Wang, John

2013-01-01

373

Hydrogen component fugacity in binary mixtures with carbon monoxide: Temperature dependence  

NASA Astrophysics Data System (ADS)

The fugacity coefficients of hydrogen in binary mixtures with carbon monoxide were measured using a physical equilibrium technique. This technique involves the use of an experimental chamber which is divided into two regions by a semipermeable membrane through which hydrogen, but not carbon monoxide, can penetrate. Measurement of the gas pressures inside and outside of the membrane allows a direct measurement of the hydrogen component fugacity at a given temperature and binary mixture mole fraction. In this paper, results are reported at 130, 160, and 190°C. In each case, the total pressure of the mixture was maintained at a nominal value of 3.39 MPa. The general qualitative features of the data are discussed, and comparisons are made with predictions obtained from the Redlich-Kwong, Peng-Robinson-Soave, and extended corresponding-state models.

Bruno, T. J.; Schroeder, J. A.

1988-07-01

374

Carbon monoxide and nitrogen dioxide exposures in indoor ice skating rinks.  

PubMed

Exposures to carbon monoxide (CO) and nitrogen dioxide (NO2) were determined in seven enclosed ice skating rinks and an outdoor rink. The uptake of CO was also determined by the difference in alveolar CO concentration of the non-smoking hockey players before and after games. Carbon monoxide concentrations in enclosed rinks ranged from 4 to 117 ppm and NO2 concentrations from 342 to 2729 ppb for 2 h hockey games. The CO uptakes were linearly related to the ambient CO concentrations. Alveolar CO of the hockey players increased on average by 0.53 ppm per 1 ppm CO exposure over 2 h. Considering the CO and NO2 levels currently measured in enclosed ice skating rinks, indoor air quality guidelines or standards should be established. It is recommended that 1 h maximum allowable limits of 20 ppm CO and 250 ppb NO2 be established. PMID:8064974

Lee, K; Yanagisawa, Y; Spengler, J D; Nakai, S

1994-06-01

375

The distribution of middle tropospheric carbon monoxide during early October 1984  

SciTech Connect

The distribution of middle tropospheric carbon monoxide measure by the Measurement of Air Pollution from Satellites (MAPS) instrument carried aboard the space shuttle is reported. The data represent average mixing ratios in the middle troposphere and are presented in the form of maps that show the carbon monoxide mixing ratios averaged for 6 days of the mission. Comparisons with concurrent, direct measurements taken aboard aircraft show that the inferred concentrations are systematically low by from 20 to 40 percent depending upon which direct measurement calibration standard is used. The data show that there are very large CO sources resulting from biomass burning over South America and southern Africa. Measured mixing ratios were high over northeast Asia and were highly variable over Europe.

Reichle, H.G. Jr.; Connors, V.S.; Wallio, H.A.; Holland, J.A.; Sherrill, R.T.; Casas, J.C.; Gormsen, B.B.

1989-01-01

376

Carbon monoxide and oxygen combustion experiments: A demonstration of Mars in situ propellants  

NASA Technical Reports Server (NTRS)

The feasibility of using carbon monoxide and oxygen as rocket propellants was examined both experimentally and theoretically. The steady-state combustion of carbon monoxide and oxygen was demonstrated for the first time in a subscale rocket engine. Measurements of experimental characteristic velocity, vacuum specific impulse, and thrust coefficient efficiency were obtained over a mixture ratio range of 0.30 to 2.0 and a chamber pressures of 1070 and 530 kPa. The theoretical performance of the propellant combination was studied parametrically over the same mixture ratio range. In addition to one dimensional ideal performance predictions, various performance reduction mechanisms were also modeled, including finite-rate kinetic reactions, two-dimensional divergence effects and viscous boundary layer effects.

Linne, Diane L.

1991-01-01

377

Effect of cigarette smoke, nicotine, and carbon monoxide on the permeability of the arterial wall  

SciTech Connect

The association between cigarette smoking and the development of atherosclerosis is well established, but the mechanism that makes cigarettes such a potent risk factor is not understood. There is normally a constant insudation of plasma macromolecules into the arterial wall. Fibrinogen and lipids are two of the large molecules involved in atherosclerosis. Therefore, we studied the effect of cigarette smoke, nicotine, and carbon monoxide on the permeability of the canine arterial wall to /sup 125/I-labeled fibrinogen. The results show that inhaled cigarette smoke significantly and rapidly increases the permeability of the arterial wall to fibrinogen and that this effect can be produced with carbon monoxide alone but not with intravenous nicotine.

Allen, D.R.; Browse, N.L.; Rutt, D.L.; Butler, L.; Fletcher, C.

1988-01-01

378

Selective oxidation of carbon monoxide in the presence of butane and maleic anhydride  

SciTech Connect

The selective oxidation of carbon monoxide in the presence of butane and maleic anhydride has been studied over platinum- and palladium-containing zeolites as well as palladium-on-silica (Pd/SiO[sub 2]) catalysts. The results show that although a zeolite support is needed in many systems to effect a kinetic control to improve selectivity, thermodynamic control using Pd([approximately]2-4 ppm)/SiO[sub 2] is sufficient to give the desired selectivities in this system. In addition, a palladium-containing vanadium-phosphate catalyst was prepared that showed complete oxidation of carbon monoxide, conversion of butane to maleic anhydride, and no observable decomposition of the maleic anhydride. 14 refs., 4 tabs.

Corbin, D.R.; Bonifaz, C. (DuPont Company, Wilmington, DE (United States))

1994-03-01

379

Some effects of argon and helium upon explosions of carbon monoxide and oxygen  

NASA Technical Reports Server (NTRS)

Report presents the results of an investigation conducted to study the effects of the inert gases, argon and helium, upon flame speed and expansion ratio in exploding mixtures of carbon monoxide, oxygen and water.For the particular gas mixtures investigated the results show that: (1) With the possible exception of helium in small amounts the addition of inert gas always produces decreased flame speed and expansion ratio; (2) like volumes of argon and helium have very different effects upon flame speed but practically the same effect upon expansion ratio; and (3) the difference in the effect of these two gases upon speed is independent of the ratio of carbon monoxide to oxygen. A discussion of some possible modes by which inert gases may produce the observed effects is included.

Fiock, Ernst F; Roeder, Carl H

1937-01-01

380

Reductive cyclotrimerization of carbon monoxide to the deltate dianion by an organometallic uranium complex.  

PubMed

Despite the long history of the Fischer-Tropsch reaction, carbon monoxide has proven remarkably resistant to selective homologation under mild conditions. Here, we find that an organouranium(III) complex induces efficient reductive trimerization of carbon monoxide at room temperature and pressure. The result is a triangular, cyclic C3O(2-)3, or deltate, dianion held between two uranium(IV) units. The bonding within the C3O(2-)3 unit and its coordination to the two U centers have been analyzed by x-ray diffraction and density functional theory computational studies, which show a stabilizing C-C agostic interaction between the C3 core and one U center. Solution nuclear magnetic resonance studies reveal a rapid equilibration of the deltate unit between the U centers. PMID:16469921

Summerscales, Owen T; Cloke, F Geoffrey N; Hitchcock, Peter B; Green, Jennifer C; Hazari, Nilay

2006-02-10

381

Time resolved X-ray absorption spectroscopy applied during ignition of oxidation of carbon monoxide  

NASA Astrophysics Data System (ADS)

The structure of supported platinum catalyst (2 wt% Pt/Al2O3) has been determined during the sudden change in the activity of the catalyst, referred as "ignition", during oxidation of carbon monoxide. The catalyst was prepared by incipient wetness impregnation method. The active phase of the catalyst is shown to be a highly disordered platinum oxide. This surface oxide increases with the increase of carbon monoxide conversion during the ignition process, which further increased the conversion, making the process autocatalytic. The QEXAFS spectra collected at Pt L3 edge with a time resolution of 0.5 sec are compared with the standard EXAFS that are generally collected in transmission mode and are shown to be useful to extract valuable information about the changing structure of the catalyst during the ignition.

Singh, J.; Alayon, E. M. C.; Nachtegaal, M.; van Bokhoven, J. A.

2009-11-01

382

Nano-crystalline porous tin oxide film for carbon monoxide sensing  

NASA Technical Reports Server (NTRS)

A tin oxide sol is deposited on platinum electrodes (12) of a sensor (10). The sol is calcined at a temperature of 500 to 800.degree. C. to produce a thin film of tin oxide with a thickness of about 150 nm to 2 .mu. and having a nano-crystalline structure with good stability. The sensor rapidly detects reducing gases, such as carbon monoxide, or hydrocarbons and organic vapors. Sensors using films calcined at around 700.degree. C. have high carbon monoxide selectivity with a response time of around 4 minutes and a recovery time of 1 minute, and therefore provide good detection systems for detection of trace amounts of pollutants such as toxic and flammable gases in homes, industrial settings, and hospitals.

Liu, Chung-Chiun (Inventor); Savinell, Robert F. (Inventor); Jin, Zhihong (Inventor)

2000-01-01

383

Maximal aerobic capacity at several ambient concentrations of carbon monoxide at several altitudes. Research report, April 1984-January 1988  

SciTech Connect

To assess the combined effects of altitude and acute carbon monoxide exposure, 11 male and 12 female subjects, all nonsmokers in good health, were given incremental maximal aerobic-capacity tests. Each subject, after attaining the required altitude and ambient carbon monoxide level, performed the maximal aerobic capacity test. Blood samples were drawn at several points in the aerobic capacity test protocol, and analyzed for hemoglobin, hematocrit, plasma proteins, lactates, and carboxyhemoglobin. Carbon-monoxide-carboxyhemoglobin uptake rates were derived from the submaximal workloads. Despite increases in carboxyhemoglobin, no additional significant decreases in maximal aerobic capacity were observed. Immediately prior to and at maximal workloads, carbon monoxide shifted into extravascular spaces and returned to the vascular space within five minutes after exercise stopped.

Horvath, S.M.; Agnew, J.W.; Wagner, J.A.; Bedi, J.F.

1988-12-01

384

Evaluation of Factors that Might Influence Exhaust Stack Performance to Prevent Carbon Monoxide Poisonings from Houseboat Generator Exhaust.  

National Technical Information Service (NTIS)

On August 4 through 7, 2003, National Institute for Occupational Safety and Health (NIOSH) researchers evaluated control of carbon monoxide (CO) emissions and exposures on houseboats at Lee's Ford Marina on Lake Cumberland, Kentucky. This work was conduct...

D. R. Hammond G. S. Earnest R. M. Hall D. Campbell

2004-01-01

385

Studies relevant to the catalytic activation of carbon monoxide. Technical progress report, December 1, 1987--November 30, 1990.  

National Technical Information Service (NTIS)

Research activity during the current funding period (December 87 to present) of this grant has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key ste...

P. C. Ford

1990-01-01

386

Studies relevant to the catalytic activation of carbon monoxide. Technical progress report, December 1, 1990--1991.  

National Technical Information Service (NTIS)

Research activity has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key steps in the relevant catalytic cycles. Other investigations of related proc...

P. C. Ford

1991-01-01

387

Phase Equilibrium Studies for Methane/Synthesis Gas Separation: The Hydrogen-Carbon Monoxide-Methane System.  

National Technical Information Service (NTIS)

This experimental study completes an extensive investigation of vapor-liquid equilibria for hydrogen-carbon monoxide-methane ternary system and associated binaries. The composite data are of particular benefit to the supplemental gas industry, wherein the...

J. H. Hong R. Kobayashi

1982-01-01

388

Decreased methane formation from the hydrogenation of carbon monoxide using zeolite/cobalt-manganese oxide composite catalysts.  

PubMed

A composite catalyst comprising a physical mixture of a zeolite and a cobalt/manganese oxide Fischer-Tropsch catalyst decreases the formation of methane in the hydrogenation of carbon monoxide without significantly affecting conversion. PMID:12240011

Johns, M; Landon, P; Alderson, T; Hutchings, G J

2001-12-01

389

40 CFR Appendix C to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Carbon Monoxide in the...  

Code of Federal Regulations, 2010 CFR

...Non-Dispersive Infrared Photometry) Measurement Principle 1. Measurements are based on the absorption of infrared radiation by carbon monoxide (CO) in a non-dispersive photometer. Infrared energy from a source is passed...

2010-07-01

390

40 CFR Appendix C to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Carbon Monoxide in the...  

Code of Federal Regulations, 2010 CFR

...Non-Dispersive Infrared Photometry) Measurement Principle 1. Measurements are based on the absorption of infrared radiation by carbon monoxide (CO) in a non-dispersive photometer. Infrared energy from a source is passed...

2009-07-01

391

Carbon monoxide photoproduction from rice and maize leaves  

NASA Astrophysics Data System (ADS)

We investigated CO photoproduction from intact leaves of rice ( Oryza sativa L.) and maize ( Zea mays L.) by laboratory experiments. CO photoproduction showed positive correlation with light intensity and was positively dependent on oxygen concentration. The average CO photoproduction was 2.6±0.3×10 10 molecules cm -2 s -1 from rice leaves and 2.2±0.1×10 10 molecules cm -2 s -1 from maize leaves ( n=5) at a radiation intensity of 49 mW cm -2. CO photoproduction from senescent rice leaves was 9 times greater (25.7±1.5×10 10 molecules cm -2 s -1, n=2) at the same radiation intensity than from live leaves, and responded slowly to changes in oxygen concentration and light intensity. CO photoproduction showed no correlation with CO 2 concentration or humidity. This indicates that CO photoproduction in leaves is not directly controlled by carbon metabolism or stomatal conductance. The lack of dependence on stomatal conductance leads to the conclusion that the diffusion of CO from inside the leaves to the atmosphere is not a controlling factor for CO photoproduction from rice and maize leaves.

Yonemura, S.; Morokuma, M.; Kawashima, S.; Tsuruta, H.

392

DETERMINATION OF THE EXTRAVASCULAR BURDEN OF CARBON MONOXIDE (CO) ON HUMAN HEART  

Microsoft Academic Search

Noninvasive measurements of myocardial carboxymyoglobin levels (%MbCO) and oxygen tensions (PtO2) are difficult to obtain experimentally. We have developed a compartmental model which allows prediction of myocardial %MbCO levels and PtO2 for varied carbon monoxide (CO) exposures. The cardiac compartment in the model consists of vascular subcompartments which contain two tissue subcompartments varying in capillary density. Mass-balance equations for oxygen

Kinnera Erupaka

2008-01-01

393

Preparation of silicon carbide fiber from activated carbon fiber and gaseous silicon monoxide  

Microsoft Academic Search

Crystalline silicon carbide (SiC) fiber was produced by a new, simple procedure. Activated carbon fiber (ACF) was reacted with gaseous silicon monoxide and was converted to SiC fiber at elevated temperatures as low as 1,473 K. The reacted fiber consisted of submicrometer particles which were not observed in the original ACF. The SiC crystal size in the reacted fiber was

Kaoru Okada; Hitoshi Kato; Keihachiro Nakajima

1994-01-01

394

Carbon Monoxide Formation in Dry Soda Lime is Prolonged at Low Gas Flow  

Microsoft Academic Search

When exposed to volatile anesthetics containing a CHF2-group, such as isoflurane, desiccated absorbents produce carbon monoxide (CO). In the anesthesia cir- cuit, the anesthetic flow that passes through the ab- sorber varies with the minute ventilation. We sought to determine CO formation at different levels of test gas flow. Isoflurane 0.5% (series A) or 0.5% isoflurane 1 5% CO2 (series

Erich Knolle; Georg Heinze; Hermann Gilly

2001-01-01

395

Cerebral infarction due to carotid occlusion and carbon monoxide exposure. II. Influence of preganglionic cervical sympathectomy.  

PubMed Central

Unilateral cerebral infarcts were produced in the rat by ligation of one common carotid artery and subsequent exposure to carbon monoxide. The incidence and extension of brain infarcts was increased in animals with additional ipsilateral cervical preganglionic sympathectomy. Sympathectomy did not affect markedly the respiration and systemic circulation. The effect of sympathectomy was attributed to a cutaneous vasodilation, leading to an extracranial steal phenomenon. Images

Igloffstein, J; Laas, R

1983-01-01

396

Experimental study on cellular instabilities in hydrocarbon\\/hydrogen\\/carbon monoxide–air premixed flames  

Microsoft Academic Search

To investigate cell formation in methane (or propane)\\/hydrogen\\/carbon monoxide–air premixed flames, the outward propagation and development of surface cellular instabilities of centrally ignited spherical premixed flames were experimentally studied in a constant pressure combustion chamber at room temperature and elevated pressures. Additionally, unstretched laminar burning velocities and Markstein lengths of the mixtures were obtained by analyzing high-speed schlieren images. In

Tran Manh Vu; Jeong Park; Jeong Soo Kim; Oh Boong Kwon; Jin Han Yun; Sang In Keel

2011-01-01

397

Carbon monoxide-induced adventitious rooting of hypocotyl cuttings from mung bean seedling  

Microsoft Academic Search

In this paper, the regulatory role of exogenous carbon monoxide (CO) during the generation and development of adventitious\\u000a roots in mung bean (Phaseolus radiatus L. cv. Mingguang) hypocotyl cuttings was surveyed. The results indicated that, like nitric oxide (NO), CO donor Hematin induced\\u000a adventitious rooting in dose-and time-dependent manners. These responses were also proven by the addition of gaseous CO

Ji Xu; Wei Xuan; Benkai Huang; Yehua Zhou; Tengfang Ling; Sheng Xu; Wenbiao Shen

2006-01-01

398

Visible-light photocatalytic conversion of carbon monoxide to methane by nickel(II) oxide.  

PubMed

Solar Fuels: Different n- and p-type semiconductors have been investigated for sustainable solar fuel production. p-Type semiconductors, such as NiO, Fe3 O4 , Co3 O4 , and CuO, are able to reduce carbon monoxide by water or hydrogen to methane. The highest CH4 yield achieved was 17.26?mmol of CH4 per gram of catalyst using NiO in an excess of H2 . PMID:24167093

Sastre, Francesc; Corma, Avelino; García, Hermenegildo

2013-12-01

399

Pulmonary excretion of carbon monoxide in the human infant as an index of bilirubin production  

Microsoft Academic Search

A total of 45 infants, including 20 appropriate-size-for-gestational-age infants (AGAs), 19 large-size-for-gestational-age infants (LGAs) and 6 infants of diabetic mothers (IDMs), had determinations of their pulmonary excretion rate of carbon monoxide (VeCO) in the first postnatal week as an index of bilirubin production. We calculated a ratio (Rw) of birth weight to ideal weight (50th percentile for gestational age) as

David K. Stevenson; Clinton R. Ostrander; Ronald S. Cohen; John D. Johnson; Herbert C. Schwartz

1981-01-01

400

Electricity generation from carbon monoxide and syngas in a microbial fuel cell  

Microsoft Academic Search

Electricity generation in microbial fuel cells (MFCs) has been a subject of significant research efforts. MFCs employ the\\u000a ability of electricigenic bacteria to oxidize organic substrates using an electrode as an electron acceptor. While MFC application\\u000a for electricity production from a variety of organic sources has been demonstrated, very little research on electricity production\\u000a from carbon monoxide and synthesis gas

Abid Hussain; Serge R. Guiot; Punita Mehta; Vijaya Raghavan; Boris Tartakovsky

2011-01-01

401

Carbon monoxide poisoning in children riding in the back of pickup trucks  

SciTech Connect

The purpose of this study is to describe the case characteristics of a series of children poisoned with carbon monoxide while traveling in the back of pickup trucks. Pediatric cases referred for treatment of carbon monoxide poisoning with hyperbaric oxygen between 1986 and 1991 were reviewed. Those cases that occurred during travel in the back of pickup trucks were selected. Clinical follow-up by telephone interview ranged from 2 to 55 months. The study took place in a private, urban, tertiary care center in Seattle, Wash. Twenty children ranging from 4 to 16 years of age were studies. All patients were treated with hyperbaric oxygen. Of 68 pediatric patients treated for accidental carbon monoxide poisoning, 20 cases occurred as children rode in the back of pickup trucks. In 17 of these, the children were riding under a rigid closed canopy on the rear of the truck, while three episodes occurred as children rode beneath a tarpaulin. Average carboxyhemoglobin level on emergency department presentation was 18.2% {plus minus} 2.4% (mean {plus minus} SEM; range, 1.6% to 37.0%). Loss of consciousness occurred in 15 of the 20 children. One child died of cerebral edema, one had permanent neurologic deficits, and 18 had no recognizable sequelae related to the episode. In all cases, the truck exhaust system had a previously known leak or a tail pipe that exited at the rear rather than at the side of the pickup truck. Carbon monoxide poisoning is a significant hazard for children who ride in the back of pickup trucks. If possible, this practice should be avoided.

Hampson, N.B.; Norkool, D.M. (Department of Medicine, Virginia Mason Clinic, Seattle, WA (United States))

1992-01-22

402

Inverse modeling of carbon monoxide surface emissions using Climate Monitoring and Diagnostics Laboratory network observations  

Microsoft Academic Search

A three-dimensional (3-D) inverse modeling scheme is used to constrain the direct surface emissions of carbon monoxide CO. A priori estimates of CO emissions are taken from various inventories and are included in the IMAGES model to compute the distribution of CO. The modeled CO mixing ratios are compared with observations at 39 CMDL stations, averaged over the years 1990–1996.

Gabrielle Pétron; Claire Granier; Boris Khattatov; Jean-Francois Lamarque; Valery Yudin; Jean-Francois Müller; John Gille

2002-01-01

403

Inverse modeling of carbon monoxide surface emissions using Climate Monitoring and Diagnostics Laboratory network observations  

Microsoft Academic Search

A three-dimensional (3-D) inverse modeling scheme is used to constrain the direct surface emissions of carbon monoxide CO. A priori estimates of CO emissions are taken from various inventories and are included in the IMAGES model to compute the distribution of CO. The modeled CO mixing ratios are compared with observations at 39 CMDL stations, averaged over the years 1990-1996.

Gabrielle Pétron; Claire Granier; Boris Khattatov; Jean-Francois Lamarque; Valery Yudin; Jean-Francois Müller; John Gille

2002-01-01

404

Carbon monoxide inhibits Fas activating antibody-induced apoptosis in endothelial cells  

Microsoft Academic Search

Background  The extrinsic apoptotic pathway initiates when a death ligand, such as the Fas ligand, interacts with its cell surface receptor\\u000a (ie., Fas\\/CD95), forming a death-inducing signaling complex (DISC). The Fas-dependent apoptotic pathway has been implicated in\\u000a several models of lung or vascular injury. Carbon monoxide, an enzymatic product of heme oxygenase-1, exerts antiapoptotic\\u000a effects at low concentration in vitro and

Xue Wang; Yong Wang; Seon-Jin Lee; Hong Pyo Kim; Augustine MK Choi; Stefan W Ryter

2011-01-01

405

Relation of Hydrogen and Methane to Carbon Monoxide in Exhaust Gases from Internal-Combustion Engines  

NASA Technical Reports Server (NTRS)

The relation of hydrogen and methane to carbon monoxide in the exhaust gases from internal-combustion engines operating on standard-grade aviation gasoline, fighting-grade aviation gasoline, hydrogenated safety fuel, laboratory diesel fuel, and auto diesel fuel was determined by analysis of the exhaust gases. Two liquid-cooled single-cylinder spark-ignition, one 9-cylinder radial air-cooled spark-ignition, and two liquid-cooled single-cylinder compression-ignition engines were used.

Gerrish, Harold C; Tessmann, Arthur M

1935-01-01

406

A new carbon monoxide occupational dosimeter: results from a worker exposure assessment survey  

Microsoft Academic Search

The LBNL\\/QGI occupational carbon monoxide (CO) dosimeter (LOCD), a new, inexpensive CO passive sampler, was field-validated in an occupational exposure assessment study in the Moscone Convention Center (MCC) in San Francisco, CA in January, 1997. The LOCD measures time-weighed-average (TWA) CO exposures from 10 to 800 parts per million hours (ppm h; accuracy ±20%; precision 10 ppm h). This device

MICHAEL G APTE; DANIEL D COX; S KATHARINE HAMMOND; LARA A GUNDEL

1999-01-01

407

Partial oxidation of methane, methanol, formaldehyde, and carbon monoxide over silica: global reaction kinetics  

Microsoft Academic Search

Oxidation of methane (848–898K), methanol (648–748K), formaldehyde (623–673K), and carbon monoxide (673–833K) over a precipitated silica catalyst has been examined over a range of reactant and oxygen partial pressures. Conversion–selectivity relationships are used to assess the reaction network and differential reactor experiments are employed to determine the global reaction kinetics. All reactions exhibited a positive-order dependence on oxygen, partial pressure

Robert L. McCormick; Mohammad B. Al-Sahali; Gokhan O. Alptekin

2002-01-01

408

Intramolecular condensation reactions in protonated dipeptides: Carbon monoxide, water, and ammonia losses in competition  

Microsoft Academic Search

The elimination of carbon monoxide and water from a series of protonated dipeptides, [XxxYyy + H]+, is investigated by tandem mass spectrometry experiments and density functional theory. The combined results show that CO\\u000a loss occurs on the a1-y1 pathway, which begins by rearrangement of the added proton to the amide N-atom and creates the proton-bound dimer of an amino\\u000a acid

Francesco Pingitore; Michael J. Polce; Ping Wang; Chrys Wesdemiotis; Béla Paizs

2004-01-01

409

Measurements of the global distribution of carbon monoxide in the troposphere  

NASA Technical Reports Server (NTRS)

Carbon monoxide and methane grab samples were obtained simultaneously with ozone, aerosol, nitric oxide and DACOM CO measurements. Eighty grab samples were collected at various altitudes up to 19,000 ft. along a north-south flight path from Wallops Flight Center, VA to 11 N. CO and CH were analyzed by flame ionization gas chromatography with cryogenic preconcentration. The relationship between CO and O3 concentrated is examined. A comparative analysis between trends in aerosol and CO concentration is performed.

Hinton, R. R.

1982-01-01

410

Inverting for emissions of carbon monoxide from Asia using aircraft observations over the western Pacific  

Microsoft Academic Search

Abstract. We use aircraft observations of continental outflo w over the western Pacific from the TRACE-P mission (March-April, 2001), in combination with an optimal estimation inverse model, to improve emission estimates of carbon monoxide (CO) from Asia. A priori emissions and their errors are from a customised bottom-up Asian emission inventory for the TRACE-P period. The global 3-D GEOS-CHEM chemical

Paul I. Palmer; Daniel J. Jacob; Dylan B. A. Jones; Colette L. Heald; Robert M. Yantosca; Jennifer A. Logan; Glen W. Sachse; David G. Streets

2003-01-01

411

Targeted Gene Deletion of Heme Oxygenase 2 Reveals Neural Role for Carbon Monoxide  

Microsoft Academic Search

Neuronal nitric oxide synthase (nNOS) generates NO in neurons, and heme-oxygenase-2 (HO-2) synthesizes carbon monoxide (CO). We have evaluated the roles of NO and CO in intestinal neurotransmission using mice with targeted deletions of nNOS or HO-2. Immunohistochemical analysis demonstrated colocalization of nNOS and HO-2 in myenteric ganglia. Nonadrenergic noncholinergic relaxation and cyclic guanosine 3',5' monophosphate elevations evoked by electrical

Randa Zakhary; Kenneth D. Poss; Samie R. Jaffrey; Christopher D. Ferris; Susumu Tonegawa; Solomon H. Snyder

1997-01-01

412

Catalytic oxidation of carbon monoxide over gold\\/iron hydroxide catalyst at ambient conditions  

Microsoft Academic Search

Catalytic oxidation of carbon monoxide at ambient conditions has been studied over gold\\/iron hydroxide catalysts. The catalyst was prepared by a precipitation method, in which the HAuCl4 was precipitated onto a suspension of the iron hydroxide support, with a low calcination temperature. The support was composed of the mixture of iron hydroxide and iron oxide, the specific surface area was

Kuo-Ching Wu; Yu-Lan Tung; Yi-Ling Chen; Yu-Wen Chen

2004-01-01

413

Model analysis of seasonal variations in tropospheric ozone and carbon monoxide over East Asia  

Microsoft Academic Search

Temporal-spatial variations in tropospheric ozone concentrations over East Asia in the period from 1 January 2000 to 31 December\\u000a 2004 were simulated by using the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields\\u000a calculated by the Regional Atmospheric Modeling System (RAMS). The simulated concentrations of ozone and carbon monoxide were\\u000a compared with ground level observations at two

Lijie Gao; Meigen Zhang; Zhiwei Han

2009-01-01

414

Variations in the total column amounts of carbon monoxide and methane in the Antarctic atmosphere  

Microsoft Academic Search

The results of measuring the total contents of carbon monoxide and methane via the method of solar-absorption spectroscopy\\u000a are presented. The measurements were performed at the Molodezhnaya Station in 1977–1978, at the Mirny Observatory from 1982\\u000a to 1992, and at the Novolazarevskaya Station from 2003 to 2006. The character of seasonal variations in the contents of these\\u000a gases in the

F. V. Kashin; V. F. Radionov; E. I. Grechko

2007-01-01

415

Fatal unintended carbon monoxide poisoning in West Virginia from nonvehicular sources.  

PubMed Central

Based on medical examiner reports and state vital records, 1978-84, nonvehicular carbon monoxide (CO) caused 62 unintended deaths, representing 42 percent of all unintended fatal CO poisonings in West Virginia. Sources were almost always heating or cooking appliances associated with incomplete combustion of fuels (methane, butane, or propane) not commonly recognized for their potential to produce CO. Hazards included failure to provide recommended venting, neglected maintenance, or use in small areas without natural ventilation.

Baron, R C; Backer, R C; Sopher, I M

1989-01-01

416

Incidence and causes of carbon monoxide intoxication: results of an epidemiologic survey in a French department.  

PubMed

The purpose of this study was to estimate the incidence, mortality, and causes of carbon monoxide intoxications in France. A survey was conducted in the department of the Hauts-de-Seine, which is representative of the French population. Data were collected through a headquarters that had direct contact with all department emergency organizations and to a technical laboratory. During the 3-y study, 735 cases that were related to 291 events were reported. Thirty-six patients died. The average incidence of carbon monoxide intoxications was 17.5 per 100,000 inhabitants. Poisoning was caused by fires in 36 events and by car exhausts in 12. For the remaining events, causes were determined as follows for 196: water heaters (57%), boiler (20.5%), coal stove (9%), brazier (4%), cooker (2%), heating device (1.5%), and miscellaneous (6%). The main mechanisms of intoxication were a defective device, poor ventilation, or poor evacuation of combustion gases. Carbon monoxide intoxication occurs frequently in France, and preventive actions are warranted. PMID:1772262

Gajdos, P; Conso, F; Korach, J M; Chevret, S; Raphael, J C; Pasteyer, J; Elkharrat, D; Lanata, E; Geronimi, J L; Chastang, C

1991-01-01

417

Reduced tar, nicotine, and carbon monoxide exposure while smoking ultralow- but not low-yield cigarettes  

SciTech Connect

An unresolved public health issue is whether some modern cigarettes are less hazardous than other and whether patients who cannot stop smoking should be advised to switch to lower-yield cigarettes. The authors studied tar (estimated by urine mutagenicity), nicotine, and carbon monoxide exposure in habitual smokers switched from their usual brand to high- (15 mg of tar), low- (5 mg of tar), or ultralow-yield (1 mg of tar) cigarettes. There were no differences in exposure comparing high- or low-yield cigarettes, but tar and nicotine exposures were reduced by 49% and 56%, respectively, and carbon monoxide exposure by 36% while smoking ultralow-yield cigarettes. Similarly, in 248 subjects smoking their self-selected brand, nicotine intake, estimated by blood concentrations of its metabolite continine, was 40% lower in those who smoked ultralow but no different in those smoking higher yields of cigarettes. The data indicate that ultralow-yield cigarettes do deliver substantial doses of tar, nicotine, and carbon monoxide, but that exposure are considerably less than for other cigarettes.

Benowitz, N.L.; Jacob, P. III; Yu, L.; Talcott, R.; Hall, S.; Jones, R.T.

1986-07-11

418

Transient control of carbon monoxide with staged PrOx reactors  

SciTech Connect

Fuel Processor systems generate hydrogen for fuel cell systems from hydrocarbon fuels such as gasoline for automotive fuel cell systems and natural gas for stationary fuel cell systems. These fuel processor systems must remove any contaminants to levels that won't poison the fuel cell before the outlet hydrogen-rich gas stream can be used by the fuel cell to generate electricity. Carbon monoxide is a contaminant that must be removed to levels of < 100 ppm or < 10 ppm depending on the CO tolerance of the fuel cell. Typically, the last unit operation in a fuel processor is a preferential oxidation reactor or a selective oxidation reactor, which removes CO by oxidizing it to form C02. These are catalytic reactors where the catalyst and operating conditions are selected so that the oxidation rate of the carbon monoxide is higher than the oxidation rate of hydrogen, even though the hydrogen is present at much higher concentrations (> 30%) than carbon monoxide which is present at trace concentrations (< 1%).

Inbody, M. A. (Michael A.); Borup, R. L. (Rodney L.); Tafoya, J. (Jose I.)

2002-01-01

419

Correlation between black carbon aerosols, carbon monoxide and tropospheric ozone over a tropical urban site  

NASA Astrophysics Data System (ADS)

Black carbon aerosols plays an important role in the earth's radiative balance and little is known of their concentrations, distributions, source strength, and especially the aerosol chemistry of the developing world. The present study addresses the impact of back carbon aerosols on different atmospheric species like CO and tropospheric ozone over an urban environment, namely Hyderabad, India. Ozone concentration varies from 14 to 63 ppbv over the study area. Diurnal variations of ozone suggest that ozone concentration starts increasing gradually after sunrise, attaining a maximum value by evening time and decreasing gradually thereafter. Black carbon (BC) aerosol mass concentrations varies from 1471 to 11,175 ng m -3. The diurnal variations of BC suggest that the concentrations are increased by a factor of ˜2 during morning (06:00-09:00 h) and evening hours (18:00 to 22:00 h) compared to afternoon hours. Positive correlation has been observed between BC and CO ( r2=0.74) with an average slope of 6.4×10 -3 g BC/g CO. The slope between black carbon aerosol mass concentration and tropospheric ozone suggests that every 1 ?g m -3 increase in black carbon aerosol mass concentration causes a 3.5 ?g m -3 reduction in tropospheric ozone. The results have been discussed in detail in the paper.

Latha, K. Madhavi; Badarinath, K. V. S.

2004-10-01

420

Total secondary ionization coefficients and breakdown potentials of hydrogen, methane, ethylene, carbon monoxide, nitrogen, oxygen and carbon dioxide between mild steel coaxial cylinders  

Microsoft Academic Search

Breakdown potentials of hydrogen, methane, ethylene, carbon monoxide, nitrogen and carbon dioxide were measured at room and at elevated temperatures, and oxygen at 296 °K, using mild steel cylindrical electrodes. The gas pressure was varied over a range of almost four orders of magnitude, and the temperature of both the gas and the metal electrodes from 294-468 °K. Two discharge

R. Hackam

1969-01-01

421

Characterization of the Ni-Fe-C complex formed by reaction of carbon monoxide with the carbon monoxide dehydrogenase from Clostridium thermoaceticum by Q-band ENDOR  

SciTech Connect

Q-Band ENDOR studies on carbon monoxide dehydrogenase (CODH) from the acetogenic bacterium Clostridium thermoaceticum provided unambiguous evidence that the reaction of CO with CODH produces a novel metal center that includes at least one nickel, at least three iron sites, and the carbon of one CO. The {sup 57}Fe hyperfine couplings determined by ENDOR are similar to the values used in simulation of the Mossbauer spectra. EPR simulation using these A{sup Fe} values is equally good for a 4Fe or a 3Fe center. The {sup 13}C ENDOR data are consistent with the binding of a carbon atom to either the Ni or the Fe component of the spin-coupled cluster. The {sup 13}C hyperfine couplings are similar to those determined earlier for the CO-bound form of the H cluster of the Clostridium pasteurianum hydrogenase, proposed to be the active site of hydrogen activation. The {sup 61} Ni ENDOR data are the first nickel ENDOR recorded for an enzyme. The EPR simulation using the ENDOR-derived hyperfine values for {sup 61}Ni is consistent with a single nickel site in the Ni-Fe-C complex. On the basis of our results and the Mossbauer data the authors propose the stoichiometry of the components of the Ni-Fe-C complex to be Ni{sub 1}Fe{sub 3-4}S{sub {ge}}4C{sub 1}, with four acid-labile sulfides.

Fan, Chaoliang; Hoffman, B.M. (Northwestern Univ., Evanston, IL (USA)); Gorst, C.M.; Ragsdale, S.W. (Univ. of Wisconsin, Milwaukee (USA))

1991-01-01

422

Hydrogenation of carbon monoxide over coprecipitated iron-manganese catalysts in a pseudo slurry reactor  

SciTech Connect

The hydrogenation of carbon monoxide to produce low-molecular-weight olefins has been investigated over unsupported iron-manganese catalysts with an approximate manganese-to-iron atomic ratio of 2:100. Temperature distributions in the following reactor modes have been studied: a conventional dense-bed reactor; a dense-bed trickle flow reactor; a dense-bed, pseudo slurry reactor; a diluted-bed reactor; a diluted-bed trickle flow reactor; and a diluted-bed, pseudo slurry reactor. A nearly isothermal temperature distribution was observed in the diluted-bed, pseudo slurry reactor. The n-hexadecane was determined to be a suitable heat transfer liquid for the diluted-bed pseudo slurry operation. The hydrogenation of carbon monoxide in a diluted-bed reactor over coprecipitated iron-manganese catalysts obeys the Schulz-Flory weight distribution law for hydrocarbons having a carbon number of up to 15. A higher chain growth probability was observed for hydrocarbons with carbon numbers greater than 15. A complete process variable investigation was conducted in the diluted-bed reactor and in the diluted-bed, pseudo slurry reactor using n-hexadecane as the heat transfer liquid. The process variables investigated were reaction temperature, reactor pressure, H/sub 2//CO ratio, and reactant gas space velocity. The results of this investigation agreed with the data reported in the literature.

Tai, W.P.

1983-01-01

423

Influence of water table on carbon dioxide, carbon monoxide, and methane fluxes from taiga bog microcosms  

Microsoft Academic Search

Hydrological changes, particularly alterations in water table level, may largely overshadow the more direct effects of global temperature increase upon carbon cycling in arctic and subarctic wetlands. Frozen cores (n=40) of intact soils and vegetation were collected from a bog near Fairbanks, Alaska, and fluxes of COâ, CHâ, and Co in response to water table variation were studied under controlled

Dale W. Funk; E. R. Pullmann; Kim M. Peterson; Patrick M. Crill; W. D. Billings

1994-01-01

424

Interaction and reactivity of nitric oxide and carbon monoxide on ruthenium surfaces  

SciTech Connect

A multifaceted investigation of the reduction of nitric oxide by carbon monoxide using a ruthenium (102) single crystal catalyst in the pressure range 10/sup -3/ to 10 Torr and temperature range of 300 to 475/sup 0/C has been undertaken. Kinetic and isotopic results indicate that the reaction products CO/sub 2/ and N/sub 2/ were produced via two reaction mechanisms. Using a reducing gas mixture (low P/sub NO//P/sub CO/ ratio) a two site mechanism was operative involving NO dissociation. The carbon monoxide kinetic order varied from +1 to -3 and the nitric oxide order varied from +1 to 0. The catalyst under these conditions was determined to be metallic ruthenium with oxygen bonded within the first surface layer. The oxygen was unreactive and formed a (1 x 3)-0 LEED pattern. Under oxidizing conditions (high P/sub NO//P/sub CO/ ratio) the catalyst was ruthenium dioxide and the functional mechanism under these reaction conditions yielded a nitric oxide order of +2 to -4. Inclusion of a site poisoning mechanism under reducing conditions and an RuO/sub 2/ growth mechanism involving ruthenium cation transfer under oxidizing conditions into the kinetic rate laws led to an overall rate law which could be fit to the carbon monoxide and nitric oxide order plots. Using isotopically oxygen labelled reactants, it was observed that the three possible isotopes of carbon dioxide were produced. A ..gamma..-CO surface species is postulated as an intermediate in the exchange process. The reaction was observed to be initially surface structure insensitive and the reaction kinetics were derived using a Langmuir-Hinshelwood formalism.

Quick, E.E.

1980-03-01

425

Process for producing hydrogen and carbonyl sulfide from hydrogen sulfide and carbon monoxide using a heteropolyanionic metal complex catalyst  

SciTech Connect

Hydrogen and carbonyl sulfide are produced by a process comprising contracting gaseous hydrogen sulfide with gaseous carbon monoxide in the presence of a heteropolymolybdate or tungstate complex. Use of these catalysts reduce the amount of by-product carbon dioxide and methane formation and thus enhance the make of hydrogen and carbonyl sulfide.

Kuch, Ph. L.

1984-12-18

426

Short-term effects of carbon monoxide exposure on the exercise performance of subjects with coronary artery disease  

SciTech Connect

Patients with atherosclerotic cardiovascular disease may be adversely affected by the presence of carboxyhemoglobin, even at low concentrations. We investigated the effects of carbon monoxide exposure on myocardial ischemia during exercise in 63 men with documented coronary artery disease. On each test day, subjects performed two symptom-limited incremental exercise tests on a treadmill; the tests were separated by a recovery period and 50 to 70 minutes of exposure to either room air or air containing one of two concentrations of carbon monoxide (117 +/- 4.4 ppm or 253 +/- 6.1 ppm). The order of exposure was assigned randomly. On each occasion, neither the subjects nor the study personnel knew whether the subjects had been exposed to room air or to one of the concentrations of carbon monoxide. Exposure to room air resulted in a mean carboxyhemoglobin level of 0.6 percent, exposure to the lower level of carbon monoxide resulted in a carboxyhemoglobin level of 2.0 percent, and exposure to the higher level of carbon monoxide resulted in a level of 3.9 percent. An effect of carbon monoxide on myocardial ischemia was demonstrated objectively by electrocardiographic changes during exercise. We observed a decrease of 5.1 percent (90 percent confidence interval, 1.5 to 8.7 percent; P = 0.02) and a decrease of 12.1 percent (90 percent confidence interval, 9.0 to 15.3 percent; P less than or equal to 0.0001) in the length of time to a threshold ischemic ST-segment change (ST end point) after carbon monoxide exposures that produced carboxyhemoglobin levels of 2.0 percent and 3.9 percent, respectively. The length of time to the onset of angina decreased by 4.2 percent at the 2.0 percent carboxyhemoglobin level and by 7.1 percent at the 3.9 percent carboxyhemoglobin level.

Allred, E.N.; Bleecker, E.R.; Chaitman, B.R.; Dahms, T.E.; Gottlieb, S.O.; Hackney, J.D.; Pagano, M.; Selvester, R.H.; Walden, S.M.; Warren, J. (Harvard School of Public Health, Boston, MA (USA))

1989-11-23

427

Pressure-induced polymerization of carbon monoxide: disproportionation and synthesis of an energetic lactonic polymer  

SciTech Connect

We have studied pressure-induced chemical reactions in carbon monoxide using both a diamond-anvil cell and a modified large volume press. Our spectroscopic data reveal that carbon monoxide disproportionates into molecular CO{sub 2} and a solid lactone-type polymer; photochemically above 3.2 GPa, thermochemically above 5 GPa at 300K, or at 3 GPa and {approx}2000K as achieved by laser heating. The solid product can be recovered at ambient conditions with a high degree of conversion, measured to be up to 95% of the original CO. Its fundamental chemical structure includes {beta}-lactone and conjugated C=C, which can be considered a severely modified polymeric carbon suboxide with open ladders and smaller five-membered rings. The polymer is metastable at ambient conditions, spontaneously liberating CO{sub 2} gases exothermically. We find that the recovered polymer has a high energy density, 1-8 KJ/g, and is very combustible. We estimate the density of recovered CO polymer to be at least 1.65 g/cm cm{sup 3}.

Evans, W J; Lipp, M J; Yoo, C; Herberg, J L; Maxwell, R S; Nicol, M F

2005-10-04

428

Pressure-Induced Polymerization of Carbon Monoxide: Disproportionation and Synthesis of an Energetic Lactonic Polymer  

SciTech Connect

We have studied pressure-induced chemical reactions in carbon monoxide using both a diamond anvil cell and a modified large volume press. Our spectroscopic data reveal that carbon monoxide disproportionates into molecular CO{sub 2} and a solid lactone-type polymer; photochemically above 3.2 GPa, thermochemically above 5 GPa at 300 K, or at 3 GPa and {approx}2000 K as achieved by laser heating. The solid product can be recovered at ambient conditions with a high degree of conversion, measured to be up to 95% of the original CO. Its fundamental chemical structure includes {beta}-lactone and conjugated C=C, which can be considered a severely modified polymeric carbon suboxide with open ladders and smaller five-membered rings. The polymer is metastable at ambient conditions, spontaneously liberating CO{sub 2} gases exothermically. We find that the recovered polymer has a high energy density, 1-8 kJ/g, and is very combustible. We estimate the density of recovered CO polymer to be at least 1.65 g/cm{sup 3}.

Evans, W.J.; Lipp, M.J.; Yoo, C.-S.; Cynn, H.; Herberg, J.L.; Maxwell, R.S.; Nicol, M.F. (UNLV); (LLNL)

2008-10-02

429

Structural influence of ordered mesoporous carbon supports for the hydrogenation of carbon monoxide to alcohols.  

PubMed

A series of ordered mesoporous carbon materials (OMCs) possessing well-ordered nanoporosity with different mesopore structures were synthesized by the template-synthesis route. Two different pore strucutes (2-dimensional hexagonal and 3-dimensional cubic structures) and two different framework-configurations (rod-type and hollow-type carbon frameworks) are prepared by using the two different silica templates and synthetic conditions. The ordered mesoporous carbon supported promoted-rhodium catalysts were preparted by an incipient wetness method. The promoted Rh-OMC catalysts are tested by a fixed bed reactor for the catalytic conversion of syngas-to-alcohols. The characteristics of the promoted Rh-OMCs catalysts were scrutinized through a series of different techniques, including transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and N2 sorption analysis, and the catalytic performance was tested in a fixed-bed reactor. It was found that the promoted Rh-OMC catalysts exhibited the different catalytic activity and selectivity of alcohols, which could be attributed to the size of metal nanoparticles being confined by the different mesostructure of OMCs. PMID:24245283

Kim, Min-Ji; Chae, Ho-Jeong; Ha, Kyoung Su; Jeong, Kwang-Eun; Kim, Chul-Ung; Jeong, Soon-Yong; Kim, Tae-Wan

2013-11-01

430

The Reactions of Methanimine and Cyanogen with Carbon Monoxide in Prebiotic Molecular Evolution on Earth  

NASA Astrophysics Data System (ADS)

A primeval atmosphere is proposed containing simple molecules such as formaldehyde, ammonia, carbon monoxide, cyanogen and hydrogen cyanide, which have been detected in space. Chemical reactions are described for the formation of aziridine-2-one and di-azirine-3-one derivatives as potential precursors for the original synthesesis of amino-acids, proteins, pyrimidines, purines, nicotinamide and flavin. The reactions have been shown to be kinetically feasible from the overall enthalpy changes in the ZKE approximation at the MP2/6-31G^* level.

Aylward, Nigel; Bofinger, Neville

2001-12-01

431

Carbon monoxide poisoning: Novel magnetic resonance imaging pattern in the acute setting  

PubMed Central

The presentation of carbon monoxide (CO) poisoning is non-specific and highly variable. The diagnosis is made when a compatible history and examination occur in a patient with elevated carboxyhaemoglobin levels. The severity of intoxication is difficult to assess accurately based on laboratory markers alone. Magnetic resonance imaging (MRI) has been shown to have superior sensitivity to computed tomography for the detection of abnormalities post CO poisoning. We report a novel imaging pattern on MRI undertaken in the acute setting in a patient with CO intoxication. We also discuss the management and follow up of patients with CO poisoning.

2012-01-01

432

Unsuccessful suicide by carbon monoxide: a secondary benefit of emissions control  

SciTech Connect

Emission systems and devices are required on automobile engines to reduce air pollution problems. Catalytic converters have been used on most 1975 and newer automobiles to reduce hydrocarbon and carbon monoxide (CO) emissions to a value that meets the Environmental Protection Agency requirements established for 1975 and 1976. The 1980-1981 Boise, Idaho, study shows that with a functioning catalytic converter either unmeasurable or sublethal quantities of CO appear in automobile exhaust. Thus, emissions control has produced a secondary benefit in reducing the number of suicides by CO poisoning from automobile exhaust fumes.

Landers, D.

1981-11-01

433

Crystal field theory analysis of rovibrational spectra of carbon monoxide monomers isolated in solid parahydrogen.  

PubMed

We report the first rotationally resolved and completely assigned rovibrational spectrum for a nonhydride molecule rotating in the solid phase: carbon monoxide (CO) monomers isolated in cryogenic solid parahydrogen (p-H(2)). We employ a modified crystal field theory model, in which the CO molecular spectroscopic constants are taken as adjustable parameters, to make good spectroscopic assignments for all the observed features. We discuss the limitations of this approach and highlight the need for improved theoretical models of molecular rotation dynamics in quantum solids. PMID:19566167

Fajardo, Mario E; Lindsay, C Michael; Momose, Takamasa

2009-06-28

434

Nd:YGG crystal laser at 1110 nm: a potential source for detecting carbon monoxide poisoning.  

PubMed

We demonstrated a laser-diode pumped Nd-doped yttrium gallium garnet crystal laser at 1110 nm for the first time to our knowledge. By suppressing the oscillation at about 1.06 ?m, continuous-wave output power of 2.1 W at 1110 nm was achieved. With a Cr:YAG as the saturable absorber, the passive Q-switching performance at this wavelength was obtained. The shortest pulse width and largest pulse energy were 31.5 ns and 22.7 ?J, respectively. Laser radiation at this wavelength is an important source for detecting carbon monoxide poisoning by simple frequency doubling with a nonlinear crystal. PMID:21479058

Yu, Haohai; Wu, Kui; Zhang, Huaijin; Wang, Zhengping; Wang, Jiyang; Jiang, Minhua

2011-04-01

435

Research and development of a luminol-carbon monoxide flow system  

NASA Technical Reports Server (NTRS)

Adaption of the luminol-carbon monoxide injection system to a flowing type system is reported. Analysis of actual wastewater samples was carried out and revealed that bacteria can be associated with particles greater than 10 microns in size in samples such as mixed liquor. Research into the luminol reactive oxidation state indicates that oxidized iron porphyrins, cytochrome-c in particular, produce more luminol chemiluminescence than the reduced form. Correlation exists between the extent of porphyrin oxidation and relative chemiluminescence. In addition, the porphyrin nucleus is apparently destroyed under the current chemiluminescent reaction conditions.

Thomas, R. R.

1977-01-01

436

Reduction behavior of iron oxides in hydrogen and carbon monoxide atmospheres  

Microsoft Academic Search

The reduction of various iron oxides in hydrogen and carbon monoxide atmospheres has been investigated by temperature programmed reduction (TPRH2 and TPRCO), thermo-gravimetric and differential temperature analysis (TG-DTA-MS), and conventional and “in situ” XRD methods. Five different compounds of iron oxides were characterized: hematite ?-Fe2O3, goethite ?-FeOOH, ferrihydrite Fe5HO8·4H2O, magnetite Fe3O4 and wüstite FeO. In the case of iron oxide-hydroxides,

W. K. Jozwiak; E. Kaczmarek; T. P. Maniecki; W. Ignaczak; W. Maniukiewicz

2007-01-01

437

Unintentional deaths from carbon monoxide poisoning--Michigan, 1987-1989.  

PubMed

Deaths from unintentional carbon monoxide (CO) poisoning in the United States result primarily from exposure to motor-vehicle exhaust and occur more often during the cold months of the year and in northern and midwestern states (1-3). In Michigan, from 1987 through 1989, 103 deaths were related to unintentional CO poisoning. To identify approaches for prevention of unintentional CO poisoning in Michigan, the Michigan Council on Injury Control (MCIC) studied death records and medical examiner (ME) records to determine the manner of deaths related to unintentional CO poisoning in that state from 1987 through 1989. This report summarizes findings of the investigation. PMID:1279372

1992-11-27

438

Metallacarboranes structurally engineered for the reduction of carbon monoxide. Final project report  

SciTech Connect

The research conducted under this Department of Energy contract has involved the development and evaluation of various metallacarborane complexes as homogeneous catalysts for the transformation of carbon monoxide into useful chemical products. The discussions presented herein summarize our results in several areas of primary interest: (1) the evaluation of the activity of certain rhoda- and ruthenacarborane complexes as catalyst precursors for the water gas shift reaction; (2) the synthesis of heterobimetallic metallacarboranes which possess both early and late transition metal vertices; and (3) the preparation of a series of rhodacarborane complexes which have potential for use in catalysis. 18 refs., 13 figs., 1 tab.

Hawthorne, M.F.

1986-01-01

439

Highly ordered magnetic mesoporous silicas for effective elimination of carbon monoxide  

NASA Astrophysics Data System (ADS)

Catalysts based on crystalline nanoparticles of Fe metal supported on mesoporous silica have been developed. The synthetic process involves hydrogen reduction processing for high abundant Fe metal nanoparticles within the mesopores, in which impregnated Fe salt in the inner nanopores of mesoporous silica is thermally treated under hydrogen at 500 °C. Detailed characterization was achieved by XRD, XPS, BET, and HR-TEM techniques. The catalytic efficiency was demonstrated as a function of the used amounts and reaction time. The results show that more than 90% of the carbon monoxide was eliminated at room temperature during a period 80 min with 0.5 g of catalyst.

Lee, Jiho; Ho Chang, Jeong

2012-04-01

440

Detection of the Carbon Monoxide Ion (CO+) in the Interstellar Medium and a Planetary Nebula  

NASA Technical Reports Server (NTRS)

We report detection of the carbon monoxide ion (CO+) in the interstellar medium (Ml7SW) and a planetary nebula (NGC 7027). These detections are based on observations of three millimeter and submillimeter transitions in M17SW and one in NGC 7027. Chemical models suggest that CO+ should be most abundant where complex molecules are least likely to be present. In our search for CO+ we therefore minimized the chance of confusion while maximizing the probability of detection by observing regions whose chemistry is dominated by the effects of ultraviolet radiation.

Latter, William B.; Walker, Christopher K.; Maloney, Philip R.

1993-01-01

441

Performance and heat transfer characteristics of a carbon monoxide/oxygen rocket engine  

NASA Technical Reports Server (NTRS)

The combustion and heat transfer characteristics of a carbon monoxide and oxygen rocket engine were evaluated. The test hardware consisted of a calorimeter combustion chamber with a heat sink nozzle and an eighteen element concentric tube injector. Experimental results are given at chamber pressures of 1070 and 3070 kPa, and over a mixture ratio range of 0.3 to 1.0. Experimental C efficiency was between 95 and 96.5 percent. Heat transfer results are discussed both as a function of mixture ratio and axial distance in the chamber. They are also compared to a Nusselt number correlation for fully developed turbulent flow.

Linne, Diane L.

1993-01-01

442

AIRS Map of Carbon Monoxide Draped on Globe: Time Series from 8/1/2005 to 9/30/2005  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] Click on the image for movie of AIRS Map of Carbon Monoxide Draped on Globe

Forest fires and agricultural burning create large amounts of carbon monoxide. AIRS provides daily global maps of carbon monoxide from space, allowing scientists to follow the global transport of this gas day-to-day. In this image sequence, carbon monoxide pollution from agricultural burning blooms repeatedly over the Amazonian basin. The gas is then transported across the Atlantic Ocean. Carbon monoxide pollution from fires in sub-Saharan Africa is also apparent.

The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.

2007-01-01

443

Oxidation and carbidation of laser-ablated amorphized Ti particles in carbon monoxide  

NASA Astrophysics Data System (ADS)

IR laser ablation of hexagonal titanium in vacuum leads to amorphization of ablated Ti particles and when carried out in gaseous carbon monoxide it proceeds as reactive ablation involving particles amorphization, oxidation and carbidation. The films deposited in vacuum and in the presence of CO were examined by Fourier transform infrared, Raman and X-ray photoelectron spectroscopy, X-ray and electron diffraction and electron microscopy. The Ti films become oxidized upon contact with air and the Ti/C/O films are composed of Ti-O, Ti-C and C-O bonds-containing structures with Ti in Ti2+-Ti4+ state and incorporating crystalline rutile and elemental carbon. The ablation in vacuum represents a new approach to amorphous titanium and it is judged that hot ablated Ti particles are modified by reactions with CO decomposition products into amorphous Ti oxycarbides which undergo rapid post-pulse amorphization.

Jandová, V?ra; Kup?ík, Jaroslav; Bastl, Zden?k; Šubrt, Jan; Pola, Josef

2013-05-01

444

Carbon monoxide and total-hydrocarbon continuous monitoring at hazardous-waste incineration facilities  

SciTech Connect

Incineration is being viewed increasingly as the most practical, least harmful means of disposing of hazardous waste. The EPA has recently proposed continuous monitoring specifications and regulatory requirements which expand those established in 40 CFR Part 264, Subpart 0, and the associated permit rules of 40 CFR Part 270. The regulations are intended to provide additional assurance that the operation of hazardous waste incineration facilities does not pose unacceptable risk to public health. In support of these regulations, commercially-available carbon monoxide (CO) and total hydrocarbon (THC) continuous emissions monitors are being evaluated. Laboratory performance tests were conducted to determine characteristics such as calibration drift, linearity, and response time. Carbon dioxide interference in CO measurements and hydrocarbon instrument sensitivity to various hydrocarbons were also investigated. A field evaluation was conducted at a hazardous waste incinerator.

Cone, L.; Logan, T.; Rollins, R.

1989-11-01

445

Monitoring of endogenous carbon monoxide dynamics in human breath by tunable diode laser  

NASA Astrophysics Data System (ADS)

High sensitive CO gas analyzer based on tunable diode laser (TDL) was used as a real time monitor of endogenous carbon monoxide in a set of breath physiology experiments. The measurements of the CO content dynamics in exhaled air with 10 ppb sensitivity were attended with detection of carbon dioxide and O2 in breath, lung ventilation parameters, heart rate and blood analysis using conventional techniques. Temporal variations of endogenous CO in human breath caused by hyperoxia, hypoxia, hyperventilation and sport loading were first studied in real time. Scattering of the CO variation time constants was observed for different tested persons. Possible reasons for this scattering related with the organisms' physiology peculiarities are discussed.

Stepanov, Eugene V.; Daraselia, Mikhail V.; Zyrianov, Pavel V.; Shulagin, Yurii A.; Skrupskii, Vladimir A.

1996-01-01

446

Biomass burning sources of nitrogen oxides, carbon monoxide, and non-methane hydrocarbons  

SciTech Connect

Biomass burning is an important source of many key tropospheric species, including aerosols, carbon dioxide (CO{sub 2}), nitrogen oxides (NO{sub {times}}=NO+NO{sub 2}), carbon monoxide (CO), methane (CH{sub 4}), nitrous oxide (N{sub 2}O), methyl bromide (CH{sub 3}Br), ammonia (NH{sub 3}), non-methane hydrocarbons (NMHCs) and other species. These emissions and their subsequent products act as pollutants and affect greenhouse warming of the atmosphere. One important by-product of biomass burning is tropospheric ozone, which is a pollutant that also absorbs infrared radiation. Ozone is formed when CO, CH{sub 4}, and NMHCs react in the presence of NO{sub {times}} and sunlight. Ozone concentrations in tropical regions (where the bulk of biomass burning occurs) may increase due to biomass burning. Additionally, biomass burning can increase the concentration of nitric acid (HNO{sub 3}), a key component of acid rain.

Atherton, C.S.

1995-11-01

447

EXAFS of carbon monoxide oxidation on supported Pt fuel cell electrocatalysts  

SciTech Connect

The potential dependence of the extended X-ray absorption fine structure (EXAFS) obtained at the Pt L{sub III} absorption edge for a carbon supported Pt electrocatalyst exposed to carbon monoxide is presented. The data have been analyzed using the difference file method to separate the dominant contributions of the Pt neighbors from contributions to the EXAFS from the adsorbed species. The presence of adsorbed CO is clearly observed with a Pt-C distance of 1.85 {angstrom} at potentials less than 0.5 V vs. RHE. Increasing the potential above 0.5 V resulted first in the removal of the adsorbed CO and at more positive potentials, e.g., 1.05 V, in the formation of an oxide layer, as evidenced by the presence of a Pt-O coordination shell at 2.00 {angstrom}. These results demonstrate that in situ EXAFS of supported Pt electrocatalysts may be used to probe adsorbate structures.

Maniguet, S.; Mathew, R.J.; Russell, A.E.

2000-03-09

448

Manganese monoxide nanoparticles adhered to mesoporous nitrogen-doped carbons for nonaqueous lithium-oxygen batteries  

NASA Astrophysics Data System (ADS)

Manganese monoxide nanoparticles adhered to mesoporous nitrogen-doped carbons (MnO-m-N-C) have been synthesized and their influence on cycle performance of nonaqueous lithium-oxygen (Li-O2) batteries is investigated. It is found that the MnO-m-N-C composites promote both oxygen reduction and oxygen evolution reactions. They lead to reduced charge overpotentials through early decomposition of the Li2O2 particles formed on discharge, especially at the limited depth of discharge during the initial several ten cycles. Such superior activity is attributed to the good coupling between the nanosized MnO particles and the conductive mesoporous nitrogen-doped carbons, which is helpful for improving kinetics of both charge and mass transport during the cathode reactions.

Cui, Z. H.; Guo, X. X.

2014-12-01

449

Shock tube measurements of growth constants in the branched chain formaldehyde-carbon monoxide-oxygen system  

NASA Technical Reports Server (NTRS)

Exponential free radical growth constants were measured for formaldehyde carbon monoxide-oxygen systems by monitoring the growth of oxygen atom concentration as manifested by CO flame band emission. Data were obtained over the temperature range of 1200 to 2000 K. The data were analyzed using a formaldehyde oxidation mechanism involving 12 elementary reaction steps. The computed growth constants are roughly in accord with experimental values, but are much more temperature dependent. The data was also analyzed assuming formaldehyde is rapidly decomposed to carbon monoxide and hydrogen. Growth constants computed for the resulting carbon monoxide hydrogen oxygen mixtures have a temperature dependence similar to experiments; however, for most mixtures, the computed growth constants were larger than experimental values.

Brabbs, T. A.; Brokaw, R. S.

1982-01-01

450

Neuropsychological outcome after carbon monoxide exposure following a storm: a case-control study  

PubMed Central

Background The cognitive consequences of carbon monoxide (CO) poisoning are well described. However, most studies have been carried out without an ad-hoc group of control subjects. The main aim of this study was to evaluate cognitive and psychiatric outcome after CO exposure during the storm Klaus in the South West of France (January 2009) in a homogeneous group of patients compared to a group of 1:1 paired controls. Methods Patients and controls were asked to fill out questionnaires about quality of life and cognitive complaints. They then underwent a cognitive assessment derived from the Carbon Monoxide Neuropsychological Screening Battery. Psychiatric assessment was performed using subtests of the Mini International Neuropsychiatric Interview. Results 38 patients and 38 paired controls were included (mean age 38.8 years) and evaluated 51 days after the poisoning. No difference was found between groups on the cognitive complaint questionnaire but patients had a lower quality of life than controls. Patients showed significantly lower cognitive performance than controls on processing speed, mental flexibility, inhibition and working and verbal episodic memories. Patients were more depressed than controls, and suffered more from post-traumatic stress disorder. Conclusions We report the first study investigating cognitive and psychiatric outcome in consecutive patients after CO poisoning during a natural disaster, using a group comparison method. CO poisoning during storms needs to be dealt with adequately and clinicians should be aware of its possible consequences.

2014-01-01

451

Low temperature coadsorption of hydrogen and carbon monoxide on Ni(100). I. TPD, ?, and UPS studies  

NASA Astrophysics Data System (ADS)

Ultraviolet photoemission (UPS), work function change (?) and temperature programmed desorption (TPD) data are reported for carbon monoxide and hydrogen coadsorbed on Ni(100). Predosed hydrogen and postdosed carbon monoxide are intimately mixed and strongly coupled on Ni(100) at 100 K, but there is no evidence for direct C-H or O-H bonding. TPD shows sharp desorption peaks of both CO and H 2 around 210 K ( ? states). UPS shows that a single type of weakly adsorbed CO, ?-CO, exists on an H-presaturated Ni(100) surface at 100 K. This species is irreversibly converted to ?-CO after heating to 260 K to desorb some CO and H 2. The chemical bonding of the adsorbed CO changes significantly with the conversion from ? to ?-CO. Work function measurements show that the surface dipole associated with ?-CO is nearly zero. The results suggest that ?-CO has an electronic structure readily derivable from chemisorbed CO perturbed by a through-Ni interaction with hydrogen bonded to the same Ni atom or atoms.

Koel, B. E.; Peebles, D. E.; White, J. M.

1983-03-01

452

A Positive Babinski Reflex Predicts Delayed Neuropsychiatric Sequelae in Chinese Patients with Carbon Monoxide Poisoning  

PubMed Central

As the human population increased in China, the carbon monoxide is a serious environmental toxin in public health. However, predicting the delayed neuropsychiatric sequelae (DNS) of carbon monoxide poisoning (COP) has not been well studied. We investigated the independent predictors of DNS in patients with COP. This study was conducted at four hospitals in China. Data were retrospectively collected from 258 patients with COP between November 1990 and October 2011. DNS was the primary endpoint. A positive Babinski reflex was the independent predictor for DNS: sensitivity = 53.8% (95% confidence interval [CI]: 26.1–79.6), specificity = 88.6% (95% CI: 83.7–92.1), positive predictive value (PPV) = 20.0% (95% CI: 9.1–37.5), and negative predictive value (NPV) = 97.3% (95% CI: 94.0–98.9). The area under the receiver operating characteristic curve = 0.712 (95% CI: 0.544–0.880). A positive Babinski reflex was very memorable, immediately available, and applicable in clinical practice. Even when the sensitivity and PPV of a positive Babinski reflex were unsatisfactory, it had a good specificity and NPV for excluding the risk of DNS. In patients without a positive Babinski reflex, the risk for DNS was only 2.7%. This finding may help physicians make decisions about dispositions for patients with COP.

Zou, Jian-Fang; Guo, Qiming; Shao, Hua; Li, Bin; Du, Yuxiu; Liu, Maofeng; Liu, Fengling; Dai, Lixin; Chung, Min-Hsien; Lin, Hung-Jung; Guo, How-Ran; Yang, Tzu-Meng; Huang, Chien-Cheng; Hsu, Chien-Chin

2014-01-01

453

Multiphoton-induced fluorescence and ionization of B/sup 1/. sigma. /sup +/ carbon monoxide  

SciTech Connect

The B/sup 1/..sigma../sup +/ state of carbon monoxide was created by a two-photon absorption of 230-nm laser radiation. The B/sup 1/..sigma../sup +/ state was identified by the positions of the 0-0 absorption band Q-branch and the vibrational bands of B/sup 1/..sigma../sup +/ ..-->.. A/sup 1/PI fluorescence occurring in the 525-nm region. Collision-induced b/sup 3/..sigma../sup +/ ..-->.. a/sup 3/PI emission in the 350-nm region was also observed. The lifetimes of both the B/sup 1/..sigma../sup +/ state and the b/sup 3/..sigma../sup +/ state were measured as well as the self-quenching rate constants and the B/sup 1/..sigma../sup +/ quenching rate by N/sub 2/. In addition to the two-photon-induced fluorescence of B/sup 1/..sigma../sup +/ carbon monoxide, a three-photon ionization was observed. Laser power-dependence studies indicated that ionization of the B/sup 1/..sigma../sup +/ state is readily saturated, implying that most B/sup 1/..sigma../sup +/ state CO is ionized rather than fluorescing. Measurement of the polarization ratio for circularly and linearly polarized excitation of fluorescence and ionization suggests that another three-photon process is occurring and occurs more efficiently for linear polarization.

Loge, G.W.; Tiee, J.J.; Wampler, F.B.

1983-01-01

454

Field surveys of carbon monoxide in commercial settings using personal exposure monitors  

NASA Astrophysics Data System (ADS)

Miniaturized personal exposure monitors (PEMs) were employed to measure carbon monoxide (CO) in 588 different commercial settings (e.g., retail stores, office buildings, hotels, restaurants) in five California cities. Altogether, 5000 CO observations were made by recording the instantaneous instrument reading at 1-minute intervals as the investigators walked along sidewalks and into buildings. For 11 of 15 survey dates, two investigators walked side-by-side, permitting two adjacent PEMs to be compared. Quality assurance tests for 1706 pairs of values showed a very high degree of agreement. CO levels for indoor commercial settings were similar to those measured outdoors on sidewalks, apparently because the pollutant seeps into the structures from traffic outside. Although indoor levels usually were above 0 ppm, they seldom were above 9 ppm (the National Ambient Air Quality Standard for an 8-hour exposure), unless some indoor source could be identified. Carbon monoxide levels on outdoor streets did not vary greatly on different sides of the street, on corners and faces of blocks, and intersections.

Flachsbart, P. G.; Ott, W. R.

1984-02-01

455

New heme-dioxygen and carbon monoxide adducts using pyridyl or imidazolyl tailed porphyrins  

PubMed Central

Inspired by the chemistry relevant to dioxygen storage, transport and activation by metalloproteins, in particular for heme/copper oxidases, and carbon monoxide binding to metal-containing active sites as a probe or surrogate for dioxygen binding, a series of heme derived dioxygen and CO complexes have been designed, synthesized, and characterized with respect to their physical properties and reactivity. The focus of this study is in the description and comparison of three types heme-superoxo and heme-CO adducts. The starting point is in the characterization of the reduced heme complexes, [(F8)FeII], [(PPy)FeII] and [(PIm)FeII], where F8, PPy and PIm are iron(II)-porphyrinates and where PPy and PIm possess a covalently tethered axial base pyridyl or imidazolyl group, respectively. The spin-state properties of these complexes vary with solvent. The low temperature reaction between O2 and these reduced porphyrin FeII complex yield distinctive low spin heme-superoxo adducts. The dioxygen binding properties for all three complexes are shown to be reversible, via alternate argon or O2 bubbling. Carbon monoxide binds to the reduced heme-FeII precursors to form low spin heme-CO adducts. The implications for future investigations of these heme O2 and CO adducts are discussed.

Li, Yuqi; Sharma, Savita K.

2012-01-01

456

Ligand Fluorination to Optimize Preferential Oxidation (PROX) of Carbon Monoxide by Water-Soluble Rhodium Porphyrins  

PubMed Central

Catalytic, low temperature preferential oxidation (PROX) of carbon monoxide by aqueous [5,10,15,20-tetrakis(4-sulfonatophenyl)-2,3,7,8,12,13,17,18-octafluoroporphyrinato]rhodium(III) tetrasodium salt, (1[Rh(III)]) and [5,10,15,20-tetrakis(3-sulfonato-2,6-difluorophenyl)-2,3,7,8,12,13,17,18-octafluoroporphyrinato]rhodium(III) tetrasodium salt, (2[Rh(III)]) is reported. The PROX reaction occurs at ambient temperature in buffered (4 ? pH ? 13) aqueous solutions. Fluorination on the porphyrin periphery is shown to increase the CO PROX reaction rate, shift the metal centered redox potentials, and acidify ligated water molecules. Most importantly, ?-fluorination increases the acidity of the rhodium hydride complex (pKa = 2.2 ± 0.2 for 2[Rh-D]); the dramatically increased acidity of the Rh(III) hydride complex precludes proton reduction and hydrogen activation near neutral pH, thereby permitting oxidation of CO to be unaffected by the presence of H2. This new fluorinated water-soluble rhodium porphyrin-based homogenous catalyst system permits preferential oxidation of carbon monoxide in hydrogen gas streams at 308 °K using dioxygen or a sacrificial electron acceptor (indigo carmine) as the terminal oxidant.

Biffinger, Justin C.; Uppaluri, ShriHarsha; Sun, Haoran

2011-01-01

457

Deletion of the Desulfovibrio vulgaris Carbon Monoxide Sensor Invokes Global Changes in Transcription  

PubMed Central

The carbon monoxide-sensing transcriptional factor CooA has been studied only in hydrogenogenic organisms that can grow using CO as the sole source of energy. Homologs for the canonical CO oxidation system, including CooA, CO dehydrogenase (CODH), and a CO-dependent Coo hydrogenase, are present in the sulfate-reducing bacterium Desulfovibrio vulgaris, although it grows only poorly on CO. We show that D. vulgaris Hildenborough has an active CO dehydrogenase capable of consuming exogenous CO and that the expression of the CO dehydrogenase, but not that of a gene annotated as encoding a Coo hydrogenase, is dependent on both CO and CooA. Carbon monoxide did not act as a general metabolic inhibitor, since growth of a strain deleted for cooA was inhibited by CO on lactate-sulfate but not pyruvate-sulfate. While the deletion strain did not accumulate CO in excess, as would have been expected if CooA were important in the cycling of CO as a metabolic intermediate, global transcriptional analyses suggested that CooA and CODH are used during normal metabolism.

Hillesland, Kristina L.; Zane, Grant M.; Zhou, Aifen; Joachimiak, Marcin P.; He, Zhili; Zhou, Jizhong; Arkin, Adam P.; Wall, Judy D.; Stahl, David A.

2012-01-01

458

A study of carbon monoxide distribution determinations for a global transport model  

NASA Technical Reports Server (NTRS)

A system of programs which model the chemistry and transport of carbon monoxide and methane in the Earth's atmosphere on a global scale was installed onto the NASA-Langley central scientific computer network. This system, the GLOBAL system, consists of a user-friendly set of procedural files which allow for simplified pre-processing, execution, and post-processing for all program elements. The package includes procedures for obtaining the NMC meteorological data, calculating the vertical winds to satisfy mass conservation, determining the boundary layer, and executing the transport/chemical model for carbon monoxide. In addition, plotting, saving to tape, and reading from tape routines were developed. Final modifications to the subprograms for processing the input data for the transport/chemistry model have improved these data to more accurately reflect true atmospheric conditions. The transfer of the transport/chemistry model from the NCAR CRAY system to the NASA-Langley VPS-32 system was completed. The problems encountered during this process and their resolutions are discussed.

Peters, Leonard K.; Manning, James O.

1987-01-01

459

Model analysis of seasonal variations in tropospheric ozone and carbon monoxide over East Asia  

NASA Astrophysics Data System (ADS)

Temporal-spatial variations in tropospheric ozone concentrations over East Asia in the period from 1 January 2000 to 31 December 2004 were simulated by using the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields calculated by the Regional Atmospheric Modeling System (RAMS). The simulated concentrations of ozone and carbon monoxide were compared with ground level observations at two remote sites, Ryori (39.03°N, 141.82°E) and Yonagunijima (24.47°N, 123.02°E). The comparison shows that the model reproduces their seasonal variation patterns reasonably well, and simulated ozone levels are generally in good agreement with the observed ones, but carbon monoxide concentrations are underestimated. Analysis of horizontal distributions of monthly averaged ozone mixing ratios in the surface layer indicates that ozone concentrations have noticeable differences among the four seasons; they are generally higher in the spring and summer while lower in the winter, reflecting the seasonal variation of solar intensity and photochemical activity and the fact that the monsoons over East Asia are playing an important role in ozone distributions.

Gao, Lijie; Zhang, Meigen; Han, Zhiwei

2009-03-01

460

Ozone and carbon monoxide measurements at a remote maritime location, mace head, Ireland, from 1990 to 1992  

NASA Astrophysics Data System (ADS)

Despite the importance of carbon monoxide in controlling the oxidising capacity of the troposphere and as a precursor to ground level ozone in regional scale photochemical episodes, few measurements are available for northwest Europe. Hourly carbon monoxide and ozone measurements are reported here for the Mace Head site on the Atlantic coast of the Republic of Ireland, for the three-year period from 1990 to 1992. Evidence is found for the advection of air masses containing elevated concentrations of carbon monoxide, from the continent of Europe to the Mace Head site, particularly when the wind flow is easterly and southeasterly. Using the simultaneous measurements of man-made halocarbons and daily wind sector allocations, it has been possible to identify the Northern Hemisphere baseline carbon monoxide concentration at 53 N of 128 ± 4 ppb and show that there has been a significant trend to increasing concentrations over the three-year period amounting to about 0.8 ppb yr -1. The European source strength for carbon monoxide has been quantified as 128 kg head of population yr. in excellent agreement with literature emission inventories. A downward trend in European CO emissions of about 13% yr -1 has been detected, presumably reflecting the steady reduction due to motor vehicle emission regulations. Over the period from March 1987 to December 1992, the continent of Europe has been shown to be a small, net ozone sink of 2.6 2.8 ppb over all of those occasions when European air flowed out over the Atlantic Ocean over Mace Head. A ? model analysis of the observed simultaneous summertime carbon monoxide and ozone concentration variations points to between 1.7 and 7 ozone molecules being produced per NO x molecule oxidised.

Derwent, R. G.; Simmonds, P. G.; Collins, W. J.

461

Yields of tar, nicotine, and carbon monoxide in the sidestream smoke from 15 brands of Canadian cigarettes  

SciTech Connect

Sidestream smoke yields for 15 brands of cigarettes were determined under conditions where mainstream yields were approximately equal to those used for determining the values which appear on packages of Canadian cigarettes. Sidestream yields of tar, nicotine, and carbon monoxide were much higher than mainstream yields for all brands tested. The average sidestream-to-mainstream ratios for the 15 brands were 3.5, 6.6, and 6.8 for tar, nicotine, and carbon monoxide, respectively. The highest yields of sidestream were obtained from the brands with the lowest mainstream yields.

Rickert, W.S.; Robinson, J.C.; Collishaw, N.

1984-03-01

462

The effect of ambient conditions on carbon monoxide emissions from an idling gas turbine combustor. M.S. Thesis  

NASA Technical Reports Server (NTRS)

A test program employing a gas turbine combustor is outlined; the results of which quantize the effects of changes in ambient temperature and humidity on carbon monoxide emissions at simulated idle operating conditions. A comparison of the experimental results with analytical results generated by a kinetic model of the combustion process, and reflecting changing ambient conditions, is given. It is demonstrated that for a complete range of possible ambient variations, significant changes do occur in the amount of carbon monoxide emitted by a gas turbine at idle, and that the analytical model is reasonably successful in predicting changes.

Subramanian, A. K.

1977-01-01

463

The effect of ambient temperature and humidity on the carbon monoxide emissions of an idling gas turbine  

NASA Technical Reports Server (NTRS)

Changes in ambient temperature and humidity affect the exhaust emissions of a gas turbine engine. The results of a test program employing a JT8D combustor are presented which quantize the effect of these changes on carbon monoxide emissions at simulated idle operating conditions. Analytical results generated by a kinetic model of the combustion process and reflecting changing ambient conditions are given. It is shown that for a complete range of possible ambient variations, significant changes do occur in the amount of carbon monoxide emitted by a gas turbine engine.

Kauffman, C. W.; Subramaniam, A. K.

1977-01-01

464

The environmental impact on air quality and exposure to carbon monoxide from charcoal production in southern Brazil.  

PubMed

Black wattle silviculture is an important activity in southern Brazil. Much of the wood is used in the production of charcoal and the pyrolysis products impacts on air quality. This paper estimates the level of atmospheric contamination from the production of charcoal in one region of Brazil. We describe a low-cost charcoal kiln that can capture condensable gases and we estimate the levels of exposure of kiln workers to carbon monoxide. The latter results indicated that exposure to carbon monoxide can be reduced from an average of 950 ppm to 907 ppm and the mass of gases reduced by 16.8%. PMID:22541721

Gomes, Gabriel Meneghetti Faé; Encarnação, Fábio

2012-07-01

<