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Energy Technology Data Exchange (ETDEWEB)
NONE
1994-12-31
The document identifies the main sources of carbon monoxide (CO) in the general outdoor atmosphere, describes methods of measuring and monitoring its concentration levels in the United Kingdom, and discusses the effects of carbon monoxide on human health. Following its review, the Panel has put forward a recommendation for an air quality standard for carbon monoxide in the United Kingdom of 10 ppm, measured as a running 8-hour average. The document includes tables and graphs of emissions of CO, in total and by emission source, and on the increase in blood levels of carboxyhaemoglobin with continuing exposure to CO. 11 refs., 4 figs., 4 tabs.
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Full Text Available ... Education Safety Education Centers Carbon Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as CO, is called the " ...
CO2 Reduction Catalyzed by Nitrogenase: Pathways to Formate, Carbon Monoxide, and Methane
Khadka, Nimesh; Dean, Dennis R.; Smith, Dayle; Hoffman, Brian M.; Raugei, Simone; Seefeldt, Lance C.
2016-01-01
The reduction of N2 to NH3 by Mo-dependent nitrogenase at its active-site metal cluster FeMo-cofactor utilizes reductive elimination (re) of Fe-bound hydrides with obligatory loss of H2 to activate the enzyme for binding/reduction of N2. Earlier work showed that wild type nitrogenase and a nitrogenase having amino acid substitutions in the MoFe protein near FeMo-cofactor can catalytically reduce CO2 by 2 or 8 electrons/protons to carbon monoxide (CO) and methane (CH4) at low rates. Here, it i...
Catalytic activity of Co/SiO2 and Co/TiO2 nanosized systems in the oxidation of carbon monoxide
Kelyp, A. A.; Smirnova, N. P.; Oleksenko, L. P.; Lutsenko, L. V.; Oranskaya, E. I.; Ripko, A. P.
2013-06-01
The effects of the preparation procedure, active component concentration, and conditions of formation of nanosized cobalt-containing systems based on TiO2 and SiO2 mesoporous powders on their catalytic activity in the oxidation of carbon monoxide were studied. The active phase in the systems was cobalt spinel CoCo2O4 found in all samples. High catalytic activity was found in the samples characterized by relatively high contents of surface active centers (cobalt cations with octahedral surroundings).
Directory of Open Access Journals (Sweden)
Alisa Wray
2016-07-01
Full Text Available Audience: This oral boards case is appropriate for all emergency medicine learners (residents, interns, and medical students. Introduction: Carbon monoxide (CO is a colorless and odorless gas that typically results from combustion. It binds hemoglobin, dissociating oxygen, causing headache, weakness, confusion and possible seizure or coma. Pulse oxygen levels may be falsely elevated. Practitioners should maintain a high index of suspicion for carbon monoxide poisoning. If caught early CO poisoning is reversible with oxygen or hyperbaric oxygen therapy. Objectives: The learner will assess a patient with altered mental status and weakness, ultimately identifying that the patient has carbon monoxide poisoning. The learner will treat the patient with oxygen and admit/transfer the patient for hyperbaric oxygenation. Method: Oral boards case
International Nuclear Information System (INIS)
Masuoka, T.; Nakamura, E.
1993-01-01
Single-, double-, and triple-photoionization processes of carbon monoxide (CO) have been studied in the photon-energy region of 37--100 eV by use of time-of-flight mass spectrometry and a photoion-photoion-coincidence method together with synchrotron radiation. The single-, double-, and triple-photoionization cross sections of CO are determined. Ion branching ratios and the partial cross sections for the individual ions respectively produced from the precursors CO + and CO 2+ are determined separately at excitation energies where the molecular and dissociative single- and double-photoionization processes compete. The threshold for the molecular double photoionization was found to be 41.3±0.2 eV. Furthermore, in single photoionization, the production of CO + is dominant whereas with double photoionization dissociation becomes dominant
Bacterium oxidizing carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Kistner, A
1953-01-01
Present-day knowledge of the microbiological oxidation of carbon monoxide is based on doubtful observations and imperfect experimental procedures. By making use of shake cultures in contact with gas mixtures containing high concentrations of CO and by employing liquid enrichment media with a low content of organic matter and solid media of the same composition with not more than 1.2% agar, it proved possible to isolate a co-oxidizing bacterium of the genus hydrogenomonas from sewage sludge. For the first time irrefutable proof has been given of the oxidation of carbon monoxide by a pure culture of a bacterium, both in growing cultures and in resting cell suspensions. 12 references.
Carbon Monoxide Information Center
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Carbon monoxide and carbon dioxide interaction with tantalum
International Nuclear Information System (INIS)
Belov, V.D.; Ustinov, Yu.K.; Komar, A.P.
1978-01-01
The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (α and β' 1 ) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the β' 1 state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10 12 sec -1 , and γ = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively. (Auth.)
Carbon monoxide and carbon dioxide interaction with tantalum
Energy Technology Data Exchange (ETDEWEB)
Belov, V D; USTINOV, YU K; KOMAR, A P [AN SSSR, LENINGRAD. FIZIKO-TEKHNICHESKIJ INST.
1978-03-01
The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (..cap alpha.. and ..beta..'/sub 1/) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the ..beta..'/sub 1/ state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10/sup 12/ sec/sup -1/, and ..gamma.. = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively.
CO2 Reduction Catalyzed by Nitrogenase: Pathways to Formate, Carbon Monoxide, and Methane.
Khadka, Nimesh; Dean, Dennis R; Smith, Dayle; Hoffman, Brian M; Raugei, Simone; Seefeldt, Lance C
2016-09-06
The reduction of N2 to NH3 by Mo-dependent nitrogenase at its active-site metal cluster FeMo-cofactor utilizes reductive elimination of Fe-bound hydrides with obligatory loss of H2 to activate the enzyme for binding/reduction of N2. Earlier work showed that wild-type nitrogenase and a nitrogenase with amino acid substitutions in the MoFe protein near FeMo-cofactor can catalytically reduce CO2 by two or eight electrons/protons to carbon monoxide (CO) and methane (CH4) at low rates. Here, it is demonstrated that nitrogenase preferentially reduces CO2 by two electrons/protons to formate (HCOO(-)) at rates >10 times higher than rates of CO2 reduction to CO and CH4. Quantum mechanical calculations on the doubly reduced FeMo-cofactor with a Fe-bound hydride and S-bound proton (E2(2H) state) favor a direct reaction of CO2 with the hydride ("direct hydride transfer" reaction pathway), with facile hydride transfer to CO2 yielding formate. In contrast, a significant barrier is observed for reaction of Fe-bound CO2 with the hydride ("associative" reaction pathway), which leads to CO and CH4. Remarkably, in the direct hydride transfer pathway, the Fe-H behaves as a hydridic hydrogen, whereas in the associative pathway it acts as a protic hydrogen. MoFe proteins with amino acid substitutions near FeMo-cofactor (α-70(Val→Ala), α-195(His→Gln)) are found to significantly alter the distribution of products between formate and CO/CH4.
Carbon Monoxide Information Center
Full Text Available ... Unites States die every year from accidental non-fire related CO poisoning associated with consumer products, including ... CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of ...
Carbon Monoxide Information Center
Full Text Available ... On Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide ... Related Links Recalls Safety Education Regulations, Laws & Standards Research & Statistics Business & Manufacturing Small Business Resources OnSafety Blogs ...
International Nuclear Information System (INIS)
Muradova, P.A; Djafarova, S.A; Seyfullayeva, Z.M; Efendiyev, M.R; Litvishkov, Yu. N.
2007-01-01
Full text: The results of research laws of reaction of deep oxidation of n-butane and carbon monoxide in the presence of Cu-Cr-Co/AL 2 O 3 /Al-frame catalysts are sited, with the purpose of acknowledgement of stated before assumptions on the physic oxidation-reduction mechanism of observable transformations. It is established, that dependence of an output of carbon monoxide on a degree of transformation of n-butane in an area of its relatively values, has extreme character that is typical for formation and an expenditure of intermediate products under the consecutive circuit. In area of low transformations of hydrocarbon CO and CO 2 are formed by parallel way. The generalized physic circuit of the postulated mechanism of joint transformation of n-butane and CO on three independent reactionary routes and kinetic model of process corresponding to it is offered. With use of settlement methods of optimization the estimation of parameters of the offered kinetic model has been out
Search of medical literature for indoor carbon monoxide exposure
Energy Technology Data Exchange (ETDEWEB)
Brennan, T.; Ivanovich, M.
1995-12-01
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.
Occupational medicine effects of carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Coombs, W.M. [South African Society of Occupational Medicine (South Africa)
1998-10-01
Carbon monoxide can affect the body if it is inhaled or if liquid carbon monoxide comes in contact with the eyes or skin. The effects of overexposure are discussed and a brief explanation of the toxicological effects of CO given. Methods of control of CO from common operations (exhaust fumes of internal combustion engines, the chemical industry and foundries, welding, mines or tunnels, fire damp explosions, industrial heating) are by local exhaust ventilation or use of a respiratory protective device. The South African hazardous chemical substance regulation NO. R. 1179 of 25 August 1995 stipulates maximum safe levels of CO concentration. 4 refs., 1 photo.
Carbon monoxide: The 21st century poison that goes unnoticed
International Nuclear Information System (INIS)
Hoskins, J.A.
1999-01-01
This editorial article describes the effects of carbon monoxide poisoning on human beings and the mechanisms involving carbon monoxide saturation of haemoglobin that are responsible for it. The initial research done in the mid-1800s by Claude Bernard is presented. Methods of treatment for persons poisoned by carbon monoxide are discussed and the experiments made by J.B.S. Haldane on himself by breathing in carbon monoxide are described. Acclimatisation effects observed by Haldane and his co-workers and concerning persons occupationally exposed to carbon monoxide emissions are described
Carbon monoxide: The 21st century poison that goes unnoticed
Energy Technology Data Exchange (ETDEWEB)
Hoskins, J.A. [Reigate, Surrey (United Kingdom)
1999-07-01
This editorial article describes the effects of carbon monoxide poisoning on human beings and the mechanisms involving carbon monoxide saturation of haemoglobin that are responsible for it. The initial research done in the mid-1800s by Claude Bernard is presented. Methods of treatment for persons poisoned by carbon monoxide are discussed and the experiments made by J.B.S. Haldane on himself by breathing in carbon monoxide are described. Acclimatisation effects observed by Haldane and his co-workers and concerning persons occupationally exposed to carbon monoxide emissions are described.
Kinetics of heterogeneous catalysis oxidation of carbon monoxide
International Nuclear Information System (INIS)
Khawaja, Y.; Sadiq, A.
1987-10-01
An irreversible kinetic surface-reaction model, based upon the reaction of carbon monoxide nd oxygen on a catalyst surface is investigated by means of Monte Carlo simulation. The adsorbed molecules/atoms on the surface undergo both first and second order kinetic phase transitions. The first order transition is found to occur at x/sub/co=x/sub/2=0.5255 with an error bar of 0.0003, where x/sub/co is the concentration of carbon monoxide in the gas phase. The time evolution of this catalytic reaction is studied both analytically and by computer simulation. Slightly above x/sub/2, the oxygen coverage relaxation time for the oxygen is found to diverage as the inverse of 3.54 times the absolute of the difference of x/sub/2 and x/sub/co. (orig./A.B.)
International Nuclear Information System (INIS)
2000-03-01
Carbon monoxide can be produced in severe accidents from interaction of ex-vessel molten core with concrete. Depending on the particular core-melt scenario, the type of concrete and geometric factors affecting the interaction, the quantities of carbon monoxide produced can vary widely, up to several volume percent in the containment. Carbon monoxide is a combustible gas. The carbon monoxide thus produced is in addition to the hydrogen produced by metal-water reactions and by radiolysis, and represents a possibly significant contribution to the combustible gas inventory in the containment. Assessment of possible accident loads to containment thus requires knowledge of the combustion properties of both CO and H 2 in the containment atmosphere. Extensive studies have been carried out and are still continuing in the nuclear industry to assess the threat of hydrogen in a severe reactor accident. However the contribution of carbon monoxide to the combustion threat has received less attention. Assessment of scenarios involving ex-vessel interactions require additional attention to the potential contribution of carbon monoxide to combustion loads in containment, as well as the effectiveness of mitigation measures designed for hydrogen to effectively deal with particular aspects of carbon monoxide. The topic of core-concrete interactions has been extensively studied; for more complete background on the issue and on the physical/thermal-hydraulics phenomena involved, the reader is referred to Proceedings of CSNI Specialists Meetings (Ritzman, 1987; Alsmeyer, 1992) and a State-of-Art Report (European Commission, 1995). The exact amount of carbon monoxide present in a reactor pit or in various compartments (or rooms) in a containment building is specific to the type of concrete and the accident scenario considered. Generally, concrete containing limestone and sand have a high percentage of CaCO 3 . Appendix A provides an example of results of estimates of CO and CO 2
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Pulmonary edema in acute carbon monoxide poisoning
International Nuclear Information System (INIS)
Kim, Kun Sang; Chang, Kee Hyun; Lee, Myung Uk
1974-01-01
Acute carbon monoxide poisoning has frequently occurred in Korean, because of the coal briquette being widely used as fuel in Korean residences. Carbon monoxide poisoning has been extensively studied, but it has been sparsely reported that pulmonary edema may develop in acute CO poisoning. We have noticed nine cases of pulmonary edema in acute CO poisoning last year. Other possible causes of pulmonary edema could be exclude in all cases but one. The purpose of this paper is to describe nine cases of pulmonary edema complicated in acute CO poisoning and discuss the pathogenesis and the prognosis
Pulmonary edema in acute carbon monoxide poisoning
Energy Technology Data Exchange (ETDEWEB)
Kim, Kun Sang; Chang, Kee Hyun; Lee, Myung Uk [Seoul National University College of Medicine, Seoul (Korea, Republic of)
1974-10-15
Acute carbon monoxide poisoning has frequently occurred in Korean, because of the coal briquette being widely used as fuel in Korean residences. Carbon monoxide poisoning has been extensively studied, but it has been sparsely reported that pulmonary edema may develop in acute CO poisoning. We have noticed nine cases of pulmonary edema in acute CO poisoning last year. Other possible causes of pulmonary edema could be exclude in all cases but one. The purpose of this paper is to describe nine cases of pulmonary edema complicated in acute CO poisoning and discuss the pathogenesis and the prognosis.
Carbon Monoxide Information Center
Full Text Available ... Español The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible Killer" because it's ... used or incorrectly-vented fuel-burning appliances such as furnaces, stoves, water heaters and fireplaces. Watch This ...
Development of an enzymatic sensor for carbon monoxide
International Nuclear Information System (INIS)
Hurtado, Clara; Gomez, Diana; Larmat, Fernando; Torres, Walter; Cuervo, Raul; Bravo, Enrique; Benitez, Neyla
2003-01-01
The detection and the pursuit of gases that contribute in the increase of the atmospheric contamination are a necessity, for what the electrochemical sensors have potential industrial applications for the control of the quality of the air. The development of amperometric sensor based on enzymes offers advantages, since the use of the biological component provides him high selectivity due to the great specificity of the substrate of the enzyme. The monoxide of carbon (CO) it is a polluting, poisonous gas, taken place during the incomplete combustion of organic materials (natural gas, petroleum, gasoline, coal and vegetable material). The determination of monoxide of carbon (CO) it can be reached by electrochemical mediums using the methylene blue like the electronic mediator for the enzyme monoxide of carbon oxidase (COx)
CARBON MONOXIDE AND THE NERVOUS SYSTEM
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...
Chemical production from waste carbon monoxide: its potential for energy conservation
Energy Technology Data Exchange (ETDEWEB)
Rohrmann, C.A.; Schiefelbein, G.F.; Molton, P.M.; Li, C.T.; Elliott, D.C.; Baker, E.G.
1977-11-01
Results of a study of the potential for energy conservation by producing chemicals from by-product or waste carbon monoxide (CO) from industrial sources are summarized. Extensive compilations of both industrial sources and uses for carbon monoxide were developed and included. Reviews of carbon monoxide purification and concentration technology and preliminary economic evaluations of carbon monoxide concentration, pipeline transportation and utilization of CO in the synthesis of ammonia and methanol are included. Preliminary technical and economic feasibility studies were made of producing ammonia and methanol from the by-product CO produced by a typical elemental phosphorus plant. Methanol synthesis appears to be more attractive than ammonia synthesis when using CO feedstock because of reduced water gas shift and carbon dioxide removal requirements. The economic studies indicate that methanol synthesis from CO appears to be competitive with conventional technology when the price of natural gas exceeds $0.82/million Btu, while ammonia synthesis from CO is probably not competitive until the price of natural gas exceeds $1.90/million Btu. It is concluded that there appears to be considerable potential for energy conservation in the chemical industry, by collecting CO rather than flaring it, and using it to make major chemicals such as ammonia and methanol.
Carbon monoxide, smoking, and atherosclerosis
Energy Technology Data Exchange (ETDEWEB)
Astrup, P
1973-10-01
Studies on the effects of carbon monoxide and smoking on atherosclerosis are reviewed. Nonsmokers do not run the risk of getting significantly elevated carboxyhemoglobin levels from automobile exhaust in the streets, however, they do run the risk of getting elevated carboxyhemoglobin levels from exposure to CO in closed areas such as garages and tunnels. Carboxyhemoglobin levels up to 20 percent may also be found in smokers. The central nervous system seems to be influenced by carboxyhemoglobin concentrations up to 20 percent. The myocardium may also be affected. Experimental work with rabbits exposed to carbon monoxide and cholesterol is described which proved that CO has a damaging effect on arterial walls, leading to increased permeability for various plasma components, to the formation of subendothelial edema, and to increased atheromatosis. The results indicate that the much higher risk of smokers of developing arterial disease in comparison to nonsmokers is mainly due to the inhaled CO in the tobacco smoke and not to nicotine. (Air Pollut. Abstr.)
Directory of Open Access Journals (Sweden)
Kamal Mishra
2016-01-01
Full Text Available Introduction: Carbon monoxide is known as the silent killer, being colorless, odourless, and tasteless. Initially non-irritating, it is very difficult for people to detect Carbon monoxide is a product of incomplete combustion of organic matter due to insufficient oxygen supply that prevents complete oxidation of carbon to C02. During World War II, Nazis used gas vans to kill an estimated over 700,000 prisoners by carbon monoxide poisoning. This method was also used in the gas chambers ofseveral death camps. The true number of incidents of carbon monoxide poisoning is unknown, since many non-lethal exposures go undetected From the available data, carbon monoxide poisoning is the most common cause of injury and death due to poisoning worldwide. Clinical features and management: The signs of carbon monoxide poisoning vary with concentration and length of exposure. Subtle cardiovascular or neurobehavioural effects occur at low concentration. The onset of chronic poisoning is usually insidious and easily mistaken for viral prodrome, depression, or gastroenteritis in children. The classic sign of carbon monoxide poisoning which is actually more often seen in the dead than the living is appearing red-cheeked and healthy. Cherry pink colour develops in nails, skin and mucosa. In acute poisoning, common abnormalities of posture and tone are cogwheel rigidity, opisthotonus, spasticity or flaccidity and seizures. Retinal haemorrhages and the classic cherry red skin colour are seldom seen. Different people andpopulations may have different carbon monoxide tolerance levels. On average, exposures at 100ppm or greater is dangerous to human health. Treatment and prevention: The mainstay of treatment is 100% oxygen administration until the COHb level is normal When the patient is stable enough to be transported, hyperbaric oxygen (HBOT should be considered This treatment is safe and well tolerated Public education about the danger of carbon monoxide, with
Carbon Monoxide Exposure in Youth Ice Hockey.
Macnow, Theodore; Mannix, Rebekah; Meehan, William P
2017-11-01
To examine the effect of ice resurfacer type on carboxyhemoglobin levels in youth hockey players. We hypothesized that players in arenas with electric resurfacers would have normal, stable carboxyhemoglobin levels during games, whereas those in arenas with internal combustion engine (IC) resurfacers would have an increase in carboxyhemoglobin levels. Prospective cohort study. Enclosed ice arenas in the northeastern United States. Convenience sample of players aged 8 to 18 years old in 16 games at different arenas. Eight arenas (37 players) used an IC ice resurfacer and 8 arenas (36 players) an electric resurfacer. Carboxyhemoglobin levels (SpCO) were measured using a pulse CO-oximeter before and after the game. Arena air was tested for carbon monoxide (CO) using a metered gas detector. Players completed symptom questionnaires. The change in SpCO from pregame to postgame was compared between players at arenas with electric versus IC resurfacers. Carbon monoxide was present at 6 of 8 arenas using IC resurfacers, levels ranged from 4 to 42 parts per million. Carbon monoxide was not found at arenas with electric resurfacers. Players at arenas with IC resurfacers had higher median pregame SpCO levels compared with those at electric arenas (4.3% vs 1%, P carboxyhemoglobin during games and have elevated baseline carboxyhemoglobin levels compared with players at arenas with electric resurfacers. Electric resurfacers decrease the risk of CO exposure.
The deployment of carbon monoxide wireless sensor network (CO-WSN) for ambient air monitoring.
Chaiwatpongsakorn, Chaichana; Lu, Mingming; Keener, Tim C; Khang, Soon-Jai
2014-06-16
Wireless sensor networks are becoming increasingly important as an alternative solution for environment monitoring because they can reduce cost and complexity. Also, they can improve reliability and data availability in places where traditional monitoring methods are difficult to site. In this study, a carbon monoxide wireless sensor network (CO-WSN) was developed to measure carbon monoxide concentrations at a major traffic intersection near the University of Cincinnati main campus. The system has been deployed over two weeks during Fall 2010, and Summer 2011-2012, traffic data was also recorded by using a manual traffic counter and a video camcorder to characterize vehicles at the intersection 24 h, particularly, during the morning and evening peak hour periods. According to the field test results, the 1 hr-average CO concentrations were found to range from 0.1-1.0 ppm which is lower than the National Ambient Air Quality Standards (NAAQS) 35 ppm on a one-hour averaging period. During rush hour periods, the traffic volume at the intersection varied from 2,067 to 3,076 vehicles per hour with 97% being passenger vehicles. Furthermore, the traffic volume based on a 1-h average showed good correlation (R2 = 0.87) with the 1-h average CO-WSN concentrations for morning and evening peak time periods whereas CO-WSN results provided a moderate correlation (R2 = 0.42) with 24 hours traffic volume due to fluctuated changes of meteorological conditions. It is concluded that the performance and the reliability of wireless ambient air monitoring networks can be used as an alternative method for real time air monitoring.
... with the Media Fire Protection Technology Carbon monoxide safety outreach materials Keep your community informed about the ... KB | Spanish PDF 592 KB Handout: carbon monoxide safety Download this handout and add your organization's logo ...
Carbon monoxide poisoning from waterpipe smoking: a retrospective cohort study.
Eichhorn, Lars; Michaelis, Dirk; Kemmerer, Michael; Jüttner, Björn; Tetzlaff, Kay
2018-04-01
Waterpipe smoking may increasingly account for unintentional carbon monoxide poisoning, a serious health hazard with high morbidity and mortality. We aimed at identifying waterpipe smoking as a cause for carbon monoxide poisoning in a large critical care database of a specialty care referral center. This retrospective cohort study included patients with a history of exposure to waterpipe smoking and carbon monoxide blood gas levels >10% or presence of clinical symptoms compatible with CO poisoning admitted between January 2013 and December 2016. Patients' initial symptoms and carbon monoxide blood levels were retrieved from records and neurologic status was assessed before and after hyperbaric oxygen treatment. Sixty-one subjects with carbon monoxide poisoning were included [41 males, 20 females; mean age 23 (SD ± 6) years; range 13-45] with an initial mean carboxyhemoglobin of 26.93% (SD ± 9.72). Most common symptoms included syncope, dizziness, headache, and nausea; 75% had temporary syncope. Symptoms were not closely associated with blood COHb levels. CO poisoning after waterpipe smoking may present in young adults with a wide variability of symptoms from none to unconsciousness. Therefore diagnosis should be suspected even in the absence of symptoms.
Conversion of carbon dioxide to carbon monoxide by pulse dielectric barrier discharge plasma
Wang, Taobo; Liu, Hongxia; Xiong, Xiang; Feng, Xinxin
2017-01-01
The conversion of carbon dioxide (CO2) to carbon monoxide (CO) was investigated in a non-thermal plasma dielectric barrier discharge (DBD) reactor, and the effects of different process conditions on the CO2 conversion were investigated. The results showed that the increase of input power could optimize the conversion of CO2 to CO. The CO2 conversion and CO yield were negatively correlated with the gas flow rate, but there was an optimum gas flow rate, that made the CO selectivity best. The carrier gas (N2, Ar) was conducive to the conversion of CO2, and the effect of N2 as carrier gas was better than Ar. The conversion of CO2 to CO was enhanced by addition of the catalyst (5A molecular sieve).
... Animals can also be poisoned by carbon monoxide. People who have pets at home may notice that their animals become ... or unresponsive from carbon monoxide exposure. Often the pets will ... these conditions. This can lead to a delay in getting help.
Kubis, Christoph; Sawall, Mathias; Block, Axel; Neymeyr, Klaus; Ludwig, Ralf; Börner, Armin; Selent, Detlef
2014-09-08
The influence of carbon monoxide concentration on the kinetics of the hydroformylation of 3,3-dimethyl-1-butene with a phosphite-modified rhodium catalyst has been studied for the pressure range p(CO)=0.20-3.83 MPa. Highly resolved time-dependent concentration profiles of the organometallic intermediates were derived from IR spectroscopic data collected in situ for the entire olefin-conversion range. The dynamics of the catalyst and organic components are described by enzyme-type kinetics with competitive and uncompetitive inhibition reactions involving carbon monoxide taken into account. Saturation of the alkyl-rhodium intermediates with carbon monoxide as a cosubstrate occurs between 1.5 and 2 MPa of carbon monoxide pressure, which brings about a convergence of aldehyde regioselectivity. Hydrogenolysis of the acyl intermediate is fast at 30 °C and low pressure of p(CO)=0.2 MPa, but is of minus first order with respect to the solution concentration of carbon monoxide. Resting 18-electron hydrido and acyl complexes that correspond to early and late rate-determining states, respectively, coexist as long as the conversion of the substrate is not complete. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Carbon monoxide (CO) intoxication: Computerized tomography and magnetic resonance
International Nuclear Information System (INIS)
Benitez Gomez, S.; Aguilera Navarro, J.M.; Gonzalez Garcia, A.; Gonzalez Marcos, J.R.; Fernandez Cruz, J.
1993-01-01
We present a case of acute carbon monoxide (CO) intoxication in a previously healthy 13-year-old girl, who was found in the bathroom, unconscious and with the gas-burning hot water thank operating. The neuroradiological study showed bilateral, symmetrical cortical and subcortical parietooccipital and temporal lesions as well as damage to the basal lymph nodes. These lesions were related to the anoxic situation induced by this type of intoxication. Clinicoradiological follow-up included CT and MR sequences over a period of 10 months. In this cases, we stress the greater sensitivity of MR in the early detection of the characteristic lesions in this situation and we analyze the evolution of the process. (Author)
Use of pulse co-oximetry as a screening and monitoring tool in mass carbon monoxide poisoning.
Bledsoe, Bryan E; Nowicki, Kevin; Creel, James H; Carrison, Dale; Severance, Harry W
2010-01-01
Carbon monoxide (CO) poisoning remains a common cause of poisoning in the United States. We describe a case where responding fire department personnel encountered a sick employee with a headache at an automotive brake manufacturing plant. Using both atmospheric CO monitoring and pulse CO-oximetry technology, fire department personnel were able to diagnose the cause of the patient's illness and later identify the source of CO in the plant.
Jans, Elijah R.; Eckert, Zakari; Frederickson, Kraig; Rich, Bill; Adamovich, Igor V.
2017-06-01
Measurements of the vibrational distribution function of carbon monoxide produced via a reaction between carbon vapor and molecular oxygen has shown a total population inversion on vibrational levels 4-7. Carbon vapor, produced using an arc discharge to sublimate graphite, is mixed with an argon oxygen flow. The excited carbon monoxide is vibrationally populated up to level v=14, at low temperatures, T=400-450 K, in a collision-dominated environment, 15-20 Torr, with total population inversions between v=4-7. The average vibrational energy per CO molecule formed by the reaction is 0.6-1.2 eV/molecule, which corresponds to 10-20% of the reaction enthalpy. Kinetic modeling of the flow reactor, including state specific vibrational processes, was performed to infer the vibrational distribution of the products of the reaction. The results show viability of developing of a new chemical CO laser from the reaction of carbon vapor and oxygen.
Energy Technology Data Exchange (ETDEWEB)
Novelli, P.C.; Conway, T.J.; Dlugokencky, E.J.; Tans, P.P. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Climate Monitoring and Diagnostics Lab.
1995-01-01
The article reviews figures for published data on recent changes of atmospheric levels of carbon dioxide, carbon monoxide and methane in terms of their sources and sinks. The largest source of CO{sub 2} is the combustion of fossil fuels, followed by emissions from deforestation and the oxidation of CO to CO{sub 2}. Carbon monoxide has an indirect influence on the earth`s radiative balance, as if levels of CO increase, levels of OH radicals decline which affects removal of other gases oxidised by this radical, notably CH{sub 4}. Major sources of CO are fossil fuel combustion, emissions from biomass, and oxidation of atmospheric CH{sub 4} and other non-methane hydrocarbons. The latest measurements suggest the depressed growth rates of CO{sub 2}, CO and CH{sub 4} have began to recover. Reasons for this are suggested. Future monitoring of atmospheric species in laboratories around the world, coupled with information on the isotopic signature of the trace gases, will improve our understanding of possible causes for trends in these gases. This will be invaluable in making policy decisions regarding future climate change. 34 refs., 4 figs.
Carbon monoxide toxicity. (Latest citations from the Life Sciences Collection database). NewSearch
Energy Technology Data Exchange (ETDEWEB)
1994-10-01
The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains a minimum of 137 citations and includes a subject term index and title list.)
Carbon Monoxide Information Center
Full Text Available ... main content Languages 简体中文 English Bahasa Indonesia 한국어 Español ภาษาไทย Tiếng Việt Text Size: Decrease Font Increase ... Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as ...
Zhou, Zhen; Ma, Shuang; Liu, Jie; Ji, Qiao-Rong; Cao, Cheng-Zhu; Li, Xiao-Na; Tang, Feng; Zhang, Wei
2018-04-25
The present study is aimed to explore the effects of endogenous carbon monoxide on the ischemia-reperfusion in rats. Wistar rats were intraperitoneally injected with protoporphyrin cobalt chloride (CoPP, an endogenous carbon monoxide agonist, 5 mg/kg), zinc protoporphyrin (ZnPP, an endogenous carbon monoxide inhibitor, 5 mg/kg) or saline. Twenty-four hours after injection, the myocardial ischemia-reperfusion model was made by Langendorff isolated cardiac perfusion system, and cardiac function parameters were collected. Myocardial cGMP content was measured by ELISA, and the endogenous carbon monoxide in plasma and myocardial enzymes in perfusate at 10 min after reperfusion were measured by colorimetry. The results showed that before ischemia the cardiac functions of CoPP, ZnPP and control groups were stable, and there were no significant differences. After reperfusion, cardiac functions had significant differences among the three groups (P endogenous carbon monoxide can maintain cardiac function, shorten the time of cardiac function recovery, and play a protective role in cardiac ischemia-reperfusion.
Directory of Open Access Journals (Sweden)
Abdul Hamid Hazrul
2017-01-01
Full Text Available Carbon monoxide (CO is a poisonous, colorless, odourless and tasteless gas. The main source of carbon monoxide is from motor vehicles and carbon monoxide levels in residential areas closely reflect the traffic density. Prediction of carbon monoxide is important to give an early warning to sufferer of respiratory problems and also can help the related authorities to be more prepared to prevent and take suitable action to overcome the problem. This research was carried out using secondary data from Department of Environment Malaysia from 2013 to 2014. The main objectives of this research is to understand the characteristic of CO concentration and also to find the most suitable time series model to predict the CO concentration in Bachang, Melaka and Kuala Terengganu. Based on the lowest AIC value and several error measure, the results show that ARMA (1,1 is the most appropriate model to predict CO concentration level in Bachang, Melaka while ARMA (1,2 is the most suitable model with smallest error to predict the CO concentration level for residential area in Kuala Terengganu.
Occult carbon monoxide poisoning.
Kirkpatrick, J N
1987-01-01
A syndrome of headache, fatigue, dizziness, paresthesias, chest pain, palpitations and visual disturbances was associated with chronic occult carbon monoxide exposure in 26 patients in a primary care setting. A causal association was supported by finding a source of carbon monoxide in a patient's home, workplace or vehicle; results of screening tests that ruled out other illnesses; an abnormally high carboxyhemoglobin level in 11 of 14 patients tested, and abatement or resolution of symptoms when the source of carbon monoxide was removed. Exposed household pets provided an important clue to the diagnosis in some cases. Recurrent occult carbon monoxide poisoning may be a frequently overlooked cause of persistent or recurrent headache, fatigue, dizziness, paresthesias, abdominal pain, diarrhea and unusual spells.
Cardiological aspects of carbon monoxide poisoning.
Marchewka, Jakub; Gawlik, Iwona; Dębski, Grzegorz; Popiołek, Lech; Marchewka, Wojciech; Hydzik, Piotr
2017-01-01
The aim of this study was to assess cardiological manifestations of carbon monoxide (CO) poisoning. Background/introduction: Carbon monoxide intoxication is one of the most important toxicological causes of morbidity and mortality worldwide. Early clinical manifestation of CO poisoning is cardiotoxicity. We enrolled 75 patients (34 males and 41 females, mean age 37.6 ± 17.7 y/o) hospitalized due to CO poisoning. Laboratory tests including troponin I, blood pressure measurements, HR and electrocardiograms (ECG) were collected. Pach's scale scoring and grading system was used to establish severity of poisoning. Grade of poisoning is positively correlated with troponin I levels and systolic blood pressure. Moreover, troponin levels are significantly correlated with exposition time, lactates and are higher in tachycardiac, hypertensive and positive ECG subpopulations. COHb levels are indicative of exposure but do not correlate with grade of poisoning. The main cause of CO poisoning were bathroom heaters - 83%, only 11% of examined intoxicated population were equipped with CO detectors. Complex cardiological screening covering troponin levels, ECG, blood pressure and heart rate measurements as well as complete blood count with particular attention to platelet parameters should be performed in each case where CO intoxication is suspected. More emphasis on education on CO poisoning is needed.
Energy Technology Data Exchange (ETDEWEB)
NONE
1995-10-01
The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)
Energy Technology Data Exchange (ETDEWEB)
NONE
1996-10-01
The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)
Assessment of exposure to carbon monoxide group of firefighters from fire fighting and rescue units
Directory of Open Access Journals (Sweden)
Jadwiga Lembas-Bogaczyk
2011-03-01
Full Text Available Firemen threat during fire burning of chemical substances indicated presence of carbon monoxide (CO in all cases. Carbon monoxide causes death of fire. Inhaled through respiratory system, links with hemoglobin, thus blocking transport and distribution of oxygen in the body. This leads to tissue anoxia, which is a direct threat to firefighters’ life. The purpose of this study was to assess the exposure to carbon monoxide of participating firefighters extinguishing fire. Estimation of carbon monoxide quantity absorbed by firefighters was isolated in a group of 40 firefighters from Fire Extinguishing and Rescue Unit of State Fire in Nysa. The study was conducted by measuring carbon monoxide in exhaled air. For measurement of carbon monoxide concentration in exhaled air Micro CO meter was used. Results were demonstrated separately for nonsmokers (n425 and smokers (n415. Mean COHb[%] levels in nonsmokers, measured prior the rescue action was 0,3950,3% and increased statistically significant after the action to 0,6150,34%, while in the group smokers, this level was 2,1750,64% before the action and increased insignificantly after the action to 2,3350,63%. The average COHb level in the same groups before and after exercise, was respectively: for nonsmokers prior to exercise was 0,4850,28% and after exercise decreased statistically significant to 0,3050,27%. In the group of smokers before exercise was 2,2350,61% and decreased statistically significant up to 1,5450,71%. It was no difference between the group of age and time of employment.
International Nuclear Information System (INIS)
Tong, Liping; Yu, K.N.; Bao, Lingzhi; Wu, Wenqing; Wang, Hongzhi; Han, Wei
2014-01-01
Highlights: • We show the possibility of modulate proliferation induced by radiation-induced bystander effect with low concentration carbon monoxide. • Carbon monoxide inhibited proliferation via modulating the transforming growth factor β1 (TGF-β1)/nitric oxide (NO) signaling pathway. • Exogenous carbon monoxide has potential application in clinical radiotherapy. - Abstract: Radiation-induced bystander effect (RIBE) has been proposed to have tight relationship with the irradiation-caused secondary cancers beyond the irradiation-treated area after radiotherapy. Our previous studies demonstrated a protective effect of low concentration carbon monoxide (CO) on the genotoxicity of RIBE after α-particle irradiation. In the present work, a significant inhibitory effect of low-dose exogenous CO, generated by tricarbonyldichlororuthenium (II) dimer [CO-releasing molecule (CORM-2)], on both RIBE-induced proliferation and chromosome aberration was observed. Further studies on the mechanism revealed that the transforming growth factor β1/nitric oxide (NO) signaling pathway, which mediated RIBE signaling transduction, could be modulated by CO involved in the protective effects. Considering the potential of exogenous CO in clinical applications and its protective effect on RIBE, the present work aims to provide a foundation for potential application of CO in radiotherapy
Energy Technology Data Exchange (ETDEWEB)
Tong, Liping [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); Yu, K.N. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); Bao, Lingzhi; Wu, Wenqing; Wang, Hongzhi [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); Han, Wei, E-mail: hanw@hfcas.cn [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China)
2014-01-15
Highlights: • We show the possibility of modulate proliferation induced by radiation-induced bystander effect with low concentration carbon monoxide. • Carbon monoxide inhibited proliferation via modulating the transforming growth factor β1 (TGF-β1)/nitric oxide (NO) signaling pathway. • Exogenous carbon monoxide has potential application in clinical radiotherapy. - Abstract: Radiation-induced bystander effect (RIBE) has been proposed to have tight relationship with the irradiation-caused secondary cancers beyond the irradiation-treated area after radiotherapy. Our previous studies demonstrated a protective effect of low concentration carbon monoxide (CO) on the genotoxicity of RIBE after α-particle irradiation. In the present work, a significant inhibitory effect of low-dose exogenous CO, generated by tricarbonyldichlororuthenium (II) dimer [CO-releasing molecule (CORM-2)], on both RIBE-induced proliferation and chromosome aberration was observed. Further studies on the mechanism revealed that the transforming growth factor β1/nitric oxide (NO) signaling pathway, which mediated RIBE signaling transduction, could be modulated by CO involved in the protective effects. Considering the potential of exogenous CO in clinical applications and its protective effect on RIBE, the present work aims to provide a foundation for potential application of CO in radiotherapy.
An unusual case of carbon monoxide poisoning.
Auger, P L; Levesque, B; Martel, R; Prud'homme, H; Bellemare, D; Barbeau, C; Lachance, P; Rhainds, M
1999-01-01
Carbon monoxide, a gas originating from incomplete combustion of carbon-based fuels, is an important cause of human deaths. In this paper, we describe an unusual carbon monoxide poisoning in a dwelling without obvious sources of combustion gases, for which two adults had to be treated in a hyperbaric chamber. Carbon monoxide readings were taken in the house and in the neighboring homes. Methane gas and nitrogen oxide levels were also monitored in the house air. Soil samples were collected around the house and tested for hydrocarbon residues. The investigation revealed the presence of a pocket of carbon monoxide under the foundation of the house. The first readings revealed carbon monoxide levels of 500 ppm in the basement. The contamination lasted for a week. The investigation indicated that the probable source of contamination was the use of explosives at a nearby rain sewer construction site. The use of explosives in a residential area can constitute a major source of carbon monoxide for the neighboring populations. This must be investigated, and public health authorities, primary-care physicians, governmental authorities, and users and manufacturers of explosives must be made aware of this problem. Images Figure 1 Figure 2 PMID:10379009
International Nuclear Information System (INIS)
Baldas, J.; Bonnyman, J.; Pojer, P.M.; Williams, G.A.
1981-10-01
Tc(S 2 CNEt 2 ) 3 CO has been prepared by the reduction of NH 4 TcO 4 with formamidinesulphinic acid in the presence of NaS 2 CNEt 2 . It is suggested that the co-ordinated carbon monoxide is formed after co-ordination of formamidinesulphinic acid, or some decomposition product, with technetium. The crystal structure of Tc(S 2 CNEt 2 ) 3 CO has been determined by single-crystal X-ray diffraction methods at 17 deg. C. Diffractometry has provided significant Bragg intensities for 2045 independent reflections and the structure has been refined by full-matrix least-squares methods to R 0.049. The compound is isostructural with the rhenium analogue and consists of discrete Tc(S 2 CNEt 2 ) 3 CO molecules, each containing a terminal linear CO group. The technetium atom has a seven co-ordinate environment which is best described as a distorted pentagonal bipyramid
Energy Technology Data Exchange (ETDEWEB)
1992-08-01
The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains a minimum of 172 citations and includes a subject term index and title list.)
Electrochemical reduction of CO2 to CO over Zn in propylene carbonate/tetrabutylammonium perchlorate
Shen, Feng-xia; Shi, Jin; Chen, Tian-you; Shi, Feng; Li, Qing-yuan; Zhen, Jian-zheng; Li, Yun-fei; Dai, Yong-nian; Yang, Bin; Qu, Tao
2018-02-01
Developing low cost and high efficient electrode for carbon dioxide (CO2) reduction in organic media is essential for practical application. Zn is a cheap metal and has high catalytic effects on CO2 reduction to carbon monoxide (CO) in aqueous solution. However, little attention has been given to investigate the performance of Zn in organic media for CO2 reduction. In present work, we have conducted CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate on Zn due to that propylene carbonate is a widely used industrial absorber, and tetrabutylammonium perchlorate is a commonly used organic supporting electrolyte. In addition, because electrochemical reduction of CO2 to CO naturally produces H2O, we have discussed water effects on CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate+6.8 wt % H2O. Our experiment results reveal that the faradaic efficiency for CO formation reaches to 83%, and the current density remains stable at 6.72 mA/cm2 at voltage -2.3 V for 4 h. Interestingly, Zn presents higher catalytic activity than Ag, and slightly lower than Au. X-ray photoelectron spectroscopy results confirm that no poisonous species is formed and absorbed on the cathode, which is an important advantage in practical application.
Characteristics of exogenous carbon monoxide deliveries
Directory of Open Access Journals (Sweden)
Hui-jun Hu
2016-01-01
Full Text Available Carbon monoxide (CO has long been considered an environmental pollutant and a poison. Exogenous exposure to amounts of CO beyond the physiologic level of the body can result in a protective or adaptive response. However, as a gasotransmitter, endogenous CO is important for multiple physiologic functions. To date, at least seven distinct methods of delivering CO have been utilized in animal and clinical studies. In this mini-review, we summarize the exogenous CO delivery methods and compare their advantages and disadvantages.
Carbon Monoxide Poisoning: Death on Mount McKinley,
1987-05-08
Additionally, studies by Astrup(5) and Thomas(6) have reported decreased erythrocytic 2, 3- diphosphoglycerate (2, 3-DPG) concentrations with acute...Halebian, et al found no significant difference in measured 02 consumption or extraction between dogs subjected to CO poisoning vs nitrogen anoxia .(9...Astrup P: Intraerythrocytic 2,3- diphosphoglycerate and carbon monoxide exposure. Ann NY Acad Sci 1970;174:252-254. 6. Thomas MF, Penny DG: Hematologic
Gas-phase studies of AunOm+ interacting with carbon monoxide
Kimble, M. L.; Castleman, A. W.
2004-04-01
The results of reactions between preformed cationic gold oxide clusters and carbon monoxide have been investigated utilizing a fast-flow reactor mass spectrometer. From these studies, it was found that all AunOm+ produced in the cluster source disappeared with CO addition at the reactant gas inlet. Furthermore, with CO addition, intermediate peaks of the form AunOm(CO)x+ (n=1-2, m=0-3, x=0-2) were produced, with some of the species continuing to react at higher CO flows.
Enzymic oxidation of carbon monoxide. II
Energy Technology Data Exchange (ETDEWEB)
Yagi, T
1959-01-01
An enzyme which catalyzes the oxidation of carbon monoxide into carbon dioxide was obtained in a cell free state from Desulfovibrio desulfuricans. The enzyme activity was assayed manometrically by measuring the rate of gas uptake under the atmosphere of carbon monoxide in the presence of benzyl-viologen as an oxidant. The optimum pH range was 7 to 8. The activity was slightly suppressed by illumination. The enzyme was more stable than hydrogenase or formate dehydrogenase against the heat treatment, suggesting that it is a different entity from these enzymes. In the absence of an added oxidant, the enzyme preparation produced hydrogen gas under the atmosphere of carbon monoxide. The phenomenon can be explained assuming the reductive decomposition of water. 17 references, 4 figures, 2 tables.
Hydrogenation of carbon monoxide over supported palladium catalysts
Energy Technology Data Exchange (ETDEWEB)
Fujimoto, K.; Hashimoto, H.; Kunugi, T.
1978-03-01
An alumina-supported 2% palladium catalyst had higher activity for carbon monoxide hydrogenation than a silica-supported 2% palladium catalyst, at 250/sup 0/-400/sup 0/C and 1 atm. The addition of lanthanum oxide or thorium oxide, but not of potassium oxide, to the silica-supported catalyst increased the conversion at 350/sup 0/C from 1.1% to 81.0% with a selectivity of 56.1% for methane, 1.4% for C/sub 2/ compounds, 0.1% for C/sub 3/ compounds, and 42.5% for carbon dioxide. Temperature-programed desorption of carbon monoxide in a hydrogen stream showed that of two desorption peaks observed for carbon monoxide, the one at higher temperature corresponded to the carbon monoxide species which hydrogenates to methane and that the area of this peak increased with increasing thorium content of the catalyst. Graphs, tables, and 12 references.
National Aeronautics and Space Administration — MAPS Overview The MAPS experiment measures the global distribution of carbon monoxide (CO) mixing ratios in the free troposphere. Because of MAPS' previous flights...
Terpolymerization of ethylene, sulfur dioxide and carbon monoxide
Johnson, R.; Steinberg, M.
This invention relates to high molecular weight terpolymer of ethylene, sulfur dioxide and carbon monoxide stable to 280/sup 0/C and containing as little as 36 mo1% ethylene and about 41 to 51 mo1% sulfur dioxide, and to the method of producing said terpolymer by irradiation of a liquid and gaseous mixture of ethylene, sulfur dioxide and carbon monoxide by means of Co-60 gamma rays or an electron beam, at a temperature of about 10 to 50/sup 0/C, and at a pressure of about 140 to 680 atmospheres, to initiate polymerization.
Forecasting approach of electrochemical valorisation of CO2 in alkali molten carbonates
International Nuclear Information System (INIS)
Chery, Deborah
2015-01-01
Carbon Dioxide is a greenhouse which can be valorised by means of electrochemical valorisation into carbon monoxide. The main goals of the thesis consist in the theoretical determination of the conductive conditions leading to this electrochemical valorisation in alkali molten carbonates along with the study of the feasibility of this electrochemical reduction in binary and ternary eutectics under experimental condition. CO 2 solubility has been determined by manometric measure and increase along with the temperature. CO 2 electrochemical experimental feasibility into CO in eutectics on gold plate electrode and graphite carbon has been proved by cyclic volt-amperometry for temperatures exceeding 550 C, without gold plate electrode pretreatment and with gold plate pretreatment by an pre-electrolysis at potential slightly negative as the CO 2 reduction potential. A global approach of reactional mechanisms implied in CO 2 reduction is proposed. (author)
Energy Technology Data Exchange (ETDEWEB)
Gewitz, H S; Voelker, W
1963-08-01
The experimental subject was the autotroph Chlorella pyrenoidosa. It was found that growth conditions determine whether the alga is inhibited by carbon monoxide or not. Respiration and photosynthesis are inhibited by carbon monoxide if the cells have grown rapidly under high light intensities. The inhibition of respiration and photosynthesis found in such cells is completely reversible. The inhibition depends not only on carbon monoxide pressure, but also on the oxygen pressure prevailing at the same time. 5 references, 1 figure, 3 tables.
Ratio of carbon monoxide to molecular hydrogen in interstellar dark clouds
International Nuclear Information System (INIS)
Dickman, R.L.; Rensselaer Polytechnic Institute; and The Ivan A. Getting Laboratories, The Aerospace Corporation)
1978-01-01
Carbon monoxide and molecular hydrogen column densities are compared at various locations within 38 interstellar dark clouds. CO column densities were obtained from radio observations of the J=1→0 transitions of the 12 C 16 O and 13 C 16 O isotopic species of the molecule. Corresponding H 2 column densities were inferred by means of visual extinctions derived from star counts, since it is argued that the standard gas-to-extinction ratio can be expected to remain valid in the clouds studied. For locations in the sources possessing line-of-sight visual extinctions in the approximate range 1.5 -2 ) = (5.0 +- 2.5) x 10 5 N 13 between molecular hydrogen and 13 CO LTE column densities. The carbon monoxide molecule can therefore be used as a quantitative ''tracer'' for the (directly unobservable) H 2 content of dark clouds. The above relationship implies that at least approx.12% of the gas-phase carbon in the clouds studied is in the form of CO, provided that the clouds are assumed to be chemically homogeneous. Langer's ion-molecule chemistry for dark clouds appears to agree well with the present work if the fractionation channel of Watson, Anicich, and Huntress is included
Borsdorff, Tobias; Andrasec, Josip; aan de Brugh, Joost; Hu, Haili; Aben, Ilse; Landgraf, Jochen
2018-01-01
In the perspective of the upcoming TROPOMI Sentinel-5 Precursor carbon monoxide data product, we discuss the benefit of using CO total column retrievals from cloud-contaminated SCIAMACHY 2.3 µm shortwave infrared spectra to detect atmospheric CO enhancements on regional and urban scales due to emissions from cities and wildfires. The study uses the operational Sentinel-5 Precursor algorithm SICOR, which infers the vertically integrated CO column together with effective cl...
Carbon monoxide mediates heme oxygenase 1 induction via Nrf2 activation in hepatoma cells
International Nuclear Information System (INIS)
Lee, Bok-Soo; Heo, JungHee; Kim, Yong-Man; Shim, Sang Moo; Pae, Hyun-Ock; Kim, Young-Myeong; Chung, Hun-Taeg
2006-01-01
Carbon monoxide (CO) and nitric oxide (NO) are two gas molecules which have cytoprotective functions against oxidative stress and inflammatory responses in many cell types. Currently, it is known that NO produced by nitric oxide synthase (NOS) induces heme oxygenase 1 (HO1) expression and CO produced by the HO1 inhibits inducible NOS expression. Here, we first show CO-mediated HO1 induction and its possible mechanism in human hepatocytes. Exposure of HepG2 cells or primary hepatocytes to CO resulted in dramatic induction of HO1 in dose- and time-dependent manner. The CO-mediated HO1 induction was abolished by MAP kinase inhibitors (MAPKs) but not affected by inhibitors of PI3 kinase or NF-κB. In addition, CO induced the nuclear translocation and accumulation of Nrf2, which suppressed by MAPKs inhibitors. Taken together, we suggest that CO induces Nrf2 activation via MAPKs signaling pathways, thereby resulting in HO1 expression in HepG2 cells
Residential indoor air quality guideline : carbon monoxide
International Nuclear Information System (INIS)
2010-01-01
Carbon monoxide (CO) is a tasteless, odourless, and colourless gas that can be produced by both natural and anthropogenic processes, but is most often formed during the incomplete combustion of organic materials. In the indoor environment, CO occurs directly as a result of emissions from indoor sources or as a result of infiltration from outdoor air containing CO. Studies have shown that the use of specific sources can lead to increased concentrations of CO indoors. This residential indoor air quality guideline examined the factors influencing the introduction, dispersion and removal of CO indoors. The health effects of exposure to low and higher concentrations of CO were discussed. Residential maximum exposure limits for CO were presented. Sources and concentrations in indoor environments were also examined. 17 refs., 2 tabs.
Mixing ratios of carbon monoxide in the troposphere
Energy Technology Data Exchange (ETDEWEB)
Novelli, P.C.; Steele, L.P. (Univ. of Colorado, Boulder (United States)); Tans, P.P. (NOAA, Boulder, CO (United States))
1992-12-20
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.
Cumulative exposure to carbon monoxide during the day
Energy Technology Data Exchange (ETDEWEB)
Joumard, R. (INRETS, 69 - Bron (FR))
The carbon monoxide, CO, has the advantage of being very easily and accurately measured under various conditions. In addition, it allows the translation of CO concentrations into their biological effects. The cumulative CO exposure should be considered according to current environment conditions during a given period of life, e.g. the day. In addition, the translation of concentrations and exposure times of CO fixed on blood haemoglobine (carboxyhaemoglobine) depends on physiological factors such as age, size, sex, or physical activity. This paper gives some examples of CO exposure translated into curves of carboxyhaemoglobine: case of 92 persons whose schedule was studied in details, of customs officers whose exposure was measured during one week, or other theoretical cases. In all the cases studied, smoking is by far the first factor of pollution by carbon monoxide. If not considering this case, the CO contents observed are preoccupying for sensitive subjects (in particular children) only in very rare cases. Furthermore, this approach allows the assessment of maximal allowable concentrations during specific exposures (work, e.g. in a tunnel) by integrating them into normal life conditions and population current exposure.
International Nuclear Information System (INIS)
Adams, J.M.; Haselden, D.A.
1984-01-01
The structure of a carbon monoxide adduct of cobalt-exchanged zeolite A, Co/sub 5.25/Na/sub 1.5/-A x 1.5CO, has been determined by Rietveld neutron profile refinement. All exchangeable cations are located in sites adjacent to the 6-ring; 3.75 of the cobalt cations sit 0.4 A inside the β-cage (Co(2)) and are arranged tetrahedrally about the eight 6-rings sites in the β-cage. The sodium cations (Na(1)) reside just inside the α-cage in sites similar to those found previously for zeolites 3A, 4A, and 5A. The remaining 1.5 cobalt cations (Co(1)) are located in sites similar to those for sodium, but they are also coordinated to the carbon monoxide molecules, which lie on, or close-to, the threefold axis which passes through the 6-ring. Inside the β-cage there is a tetrahedral aluminum complex of AlO 4 type, the oxygen atoms (O*) of which point toward six rings not occupied by cobalt cations, Co(2). Each of the oxygen atoms of this complex is involved in a hydrogen bond (2.83 A) to the 6-ring oxygen O(3). Approximately 2/3 of these bonds are of type O*-H ... O(3) and 1/3 of type O* ...H-O(3)
Carrivain, Olivier; Orain, Mikael; Dorval, Nelly; Morin, Celine; Legros, Guillaume
2017-10-01
Two-photon excitation laser-induced fluorescence of carbon monoxide (CO-LIF) is investigated experimentally in order to determine the applicability of this technique for imaging CO concentration in aeronautical combustors. Experiments are carried out in a high temperature, high-pressure test cell, and in a laminar premixed CH 4 /air flame. Influence of temperature and pressure on CO-LIF spectra intensity and shape is reported. The experimental results show that as pressure increases, the CO-LIF excitation spectrum becomes asymmetric. Additionally, the spectrum strongly shifts to the red with a quadratic dependence of the collisional shift upon pressure, which is different from the classical behavior where the collisional shift is proportional to pressure. Moreover, pressure line broadening cannot be reproduced by a Lorenztian profile in the temperature range investigated here (300-1750 K) and, therefore, an alternative line shape is suggested.
Wilkinson, B.H.P.; Janz, J.A.M.; Morel, P.C.H.; Purchas, R.W.; Hendriks, W.H.
2006-01-01
Modified atmosphere packaging with carbon dioxide is effective for prolonging shelf-life of fresh meat. Addition of carbon monoxide to the system provides the advantage of enhancing meat colour. The study objective was to determine the effect of CO2-MAP + 0.4% CO, vs. 100% CO2-MAP, on the
Carbon monoxide and COHb concentration in blood in various circumstances
Energy Technology Data Exchange (ETDEWEB)
Modic, J. [Faculty of Mechanical Engineering, University of Ljubljana, Ljubljana (Slovenia)
2003-07-01
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 (NO{sub x}), carbon oxides (CxHy) and smoke. In a living room is important the smoke of cigarettes, smoke of furnaces, improper ventilation. In tunnel is most dangerous the carbon monoxide if it exceeds an allowable level. In human blood the carbon monoxide causes increasing the concentration of carboxihemoglobyne and in this case the hypoxia of web. With help of mathematical model the concentrations of some dangerous substances at the end of tunnel were calculated. For this case a differential equation also was developed and it shows the correlation between concentration of carbon monoxide in the air and concentration of carboxihemoglobyne in the blood. The constructed mathematical model shows circumstances in the tunnel (velocity of air moving as effect of induction, concentration of noxious substances and criterial number). Also a corresponding computer program was developed, which makes possible a quick and simple calculation. All the results are proved by experiments. Finally the differential equation was done, which shows a temporal connection between both parameters as a function of tunnel characteristics. (author)
Recent changes in atmospheric carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Novelli, P.C.; Masarie, K.A. (Univ. of Colorado, Boulder, CO (United States)); Tans, P.P.; Lang, P.M. (National Oceanic and Atmospheric Administration, Boulder, CO (United States))
1994-03-18
Measurements of carbon monoxide (CO) in air samples collected from 27 locations between 71[degrees]N and 41[degrees]S show that atmospheric levels of this gas have decreased worldwide over the past 2 to 5 years. During this period, CO decreased at nearly a constant rate in the high northern latitudes. In contrast, in the tropics an abrupt decrease occurred beginning at the end of 1991. In the Northern Hemisphere, CO decreased at a spatially and temporally averaged rate of 7.3 ([+-]0.9) parts per billion per year (6.1 percent per year) from June 1990 to June 1993, whereas in the Southern Hemisphere, CO decreased 4.2 ([+-]0.5) parts per billion per year (7.0 percent per year). This recent change is opposite a long-term trend of a 1 to 2 percent per year increase inferred from measurements made in the Northern Hemisphere during the past 30 years.
Civis, Svatopluk; Babánková, Dagmar; Cihelka, Jaroslav; Sazama, Petr; Juha, Libor
2008-08-07
Large-scale plasma was created in gas mixtures containing carbon monoxide by high-power laser-induced dielectric breakdown (LIDB). The composition of the mixtures used corresponded to a cometary and/or meteoritic impact into the Earth's early atmosphere. A multiple-centimeter-sized fireball was created by focusing a single 85 J, 450 ps near-infrared laser pulse into the center of a 15 L gas cell. The excited reaction intermediates that formed in various stages of the LIDB plasma chemical evolution were investigated by optical emission spectroscopy (OES) with temporal resolution. Special attention was paid to any OES signs of molecular ions. However, carbon monoxide cations were registered only if their production was enhanced by Penning ionization, i.e., excess He was added to the CO. The chemical consequences of laser-produced plasma generation in a CO-N 2-H 2O mixture were investigated using high resolution Fourier-transform infrared absorption spectroscopy (FTIR) and gas chromatography (GC). Several simple inorganic and organic compounds were identified in the reaction mixture exposed to ten laser sparks. H 2 (18)O was used to avoid possible contamination. The large laser spark triggered more complex reactivity originating in carbon monoxide than expected, when taking into account the strong triple bond of carbon monoxide causing typically inefficient dissociation of this molecule in electrical discharges.
Carbon Monoxide Poisoning in a Child: A Case Report | Asani ...
African Journals Online (AJOL)
The exact incidence of carbon monoxide (CO) poisoning in Nigeria is unknown. Globally, CO poisoning is frequently unrecognized and under-reported since the clinical presentation is relatively non-specific. The circumstances usually involve an unsuspected increase of CO in an enclosed environment. We present the ...
Catalytic hydrogenation of carbon monoxide
International Nuclear Information System (INIS)
Wayland, B.B.
1993-12-01
Focus of this project is on developing new approaches for hydrogenation of carbon monoxide to produce organic oxygenates at mild conditions. The strategies to accomplish CO reduction are based on favorable thermodynamics manifested by rhodium macrocycles for producing a series of intermediates implicated in the catalytic hydrogenation of CO. Metalloformyl complexes from reactions of H 2 and CO, and CO reductive coupling to form metallo α-diketone species provide alternate routes to organic oxygenates that utilize these species as intermediates. Thermodynamic and kinetic-mechanistic studies are used in guiding the design of new metallospecies to improve the thermodynamic and kinetic factors for individual steps in the overall process. 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. Non-macrocyclic ligand complexes that emulate the favorable thermodynamic features associated with rhodium macrocycles, but that also manifest improved reaction kinetics are promising candidates for future development
Energy Technology Data Exchange (ETDEWEB)
Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.
1979-05-01
One hundred twenty-one brands of United States commercial cigarettes were analyzed for their deliveries of tar, nicotine, carbon monoxide, and carbon dioxide under standard analytical smoking conditions. The sample included both filter and nonfilter cigarettes. Comparisons of carbon monoxide deliveries over the range of observed tar deliveries indicated a very high correlation between CO and tar for filter cigarettes, but nonfilter cigarettes tended to produce much less CO than would have been predicted from their tar deliveries. Comparison of ORNL nicotine values for specific brands with those determined by the Federal Trade Commission yield no statistically significant differences between laboratories. 4 figures, 6 tables.
Gomółka, Ewa; Gawlikowski, Tomasz
2011-01-01
Carboxyhemoglobin is a specific biomarker of carbon monoxide (CO) exposition. The source of CO indoors are most often gas, oil or carbon furnaces and stoves or bathroom gas heaters. CO intoxication during fire or exposition to car fumes are sporadic. The aim of the study was: to present the frequency of CO intoxications diagnosed in Laboratory of Analytical Toxicology UJ Collegium Medicum in years 2002 - 2010, to present the season trends of CO intoxications, show sex and age structure of CO intoxicated patients. Material were Laboratory of Analytical Toxicology and Drug Monitoring data records from years 2002 - 2010. CO intoxication was confirmed and recognized when COHb blood concentration was higher than 10%. Annual number of CO poisonings was stable in the period of time, varied from 209 to 296 (mean 256,2 CO poisonings per year). Sex structure of CO poisoned patients showed little female dominance (54.6%). Carbon monoxide poisonings distribution was seasonal. The season of intensified CO intoxications lasted from October to March, the highest intensity was in December and January. The CO poisoning problem is still actual. Society education about security, recognition, diagnosis and practice in carbon monoxide exposition is still needful.
New Class of Hybrid Materials for Detection, Capture, and "On-Demand" Release of Carbon Monoxide.
Pitto-Barry, Anaïs; Lupan, Alexandru; Ellingford, Christopher; Attia, Amr A A; Barry, Nicolas P E
2018-04-25
Carbon monoxide (CO) is both a substance hazardous to health and a side product of a number of industrial processes, such as methanol steam reforming and large-scale oxidation reactions. The separation of CO from nitrogen (N 2 ) in industrial processes is considered to be difficult because of the similarities of their electronic structures, sizes, and physicochemical properties (e.g., boiling points). Carbon monoxide is also a major poison in fuel cells because of its adsorption onto the active sites of the catalysts. It is therefore of the utmost economic importance to discover new materials that enable effective CO capture and release under mild conditions. However, methods to specifically absorb and easily release CO in the presence of contaminants, such as water, nitrogen, carbon dioxide, and oxygen, at ambient temperature are not available. Here, we report the simple and versatile fabrication of a new class of hybrid materials that allows capture and release of carbon monoxide under mild conditions. We found that carborane-containing metal complexes encapsulated in networks made of poly(dimethylsiloxane) react with CO, even when immersed in water, leading to dramatic color and infrared signature changes. Furthermore, we found that the CO can be easily released from the materials by simply dipping the networks into an organic solvent for less than 1 min, at ambient temperature and pressure, which not only offers a straightforward recycling method, but also a new method for the "on-demand" release of carbon monoxide. We illustrated the utilization of the on-demand release of CO from the networks by carrying out a carbonylation reaction on an electron-deficient metal complex that led to the formation of the CO-adduct, with concomitant recycling of the gel. We anticipate that our sponge-like materials and scalable methodology will open up new avenues for the storage, transport, and controlled release of CO, the silent killer and a major industrial poison.
National Aeronautics and Space Administration — MAPS OverviewThe MAPS experiment measures the global distribution of carbon monoxide (CO) mixing ratios in the free troposphere. Because of MAPS' previous flights on...
Occult Carbon Monoxide Poisoning
Kirkpatrick, John N.
1987-01-01
A syndrome of headache, fatigue, dizziness, paresthesias, chest pain, palpitations and visual disturbances was associated with chronic occult carbon monoxide exposure in 26 patients in a primary care setting. A causal association was supported by finding a source of carbon monoxide in a patient's home, workplace or vehicle; results of screening tests that ruled out other illnesses; an abnormally high carboxyhemoglobin level in 11 of 14 patients tested, and abatement or resolution of symptoms ...
A carbon monoxide passive sampler: Research and development needs
Energy Technology Data Exchange (ETDEWEB)
Traynor, G.W.; Apte, M.G.; Diamond, R.C.; Woods, A.L.
1991-11-01
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.
Pathways and bioenergetics of anaerobic carbon monoxide fermentation.
Martijn eDiender; Alfons J.M. Stams; Alfons J.M. Stams; Diana Z. Sousa
2015-01-01
Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the potential of converting CO rich gas, such as synthesis gas, into bio-based products. Three main types of fermentative CO metabolism can be distinguished: hydrogenogenesis, methanogenesis and acetogenesis, ...
An unusual case of carbon monoxide poisoning.
Auger, P L; Levesque, B; Martel, R; Prud'homme, H; Bellemare, D; Barbeau, C; Lachance, P; Rhainds, M
1999-07-01
Carbon monoxide, a gas originating from incomplete combustion of carbon-based fuels, is an important cause of human deaths. In this paper, we describe an unusual carbon monoxide poisoning in a dwelling without obvious sources of combustion gases, for which two adults had to be treated in a hyperbaric chamber. Carbon monoxide readings were taken in the house and in the neighboring homes. Methane gas and nitrogen oxide levels were also monitored in the house air. Soil samples were collected around the house and tested for hydrocarbon residues. The investigation revealed the presence of a pocket of carbon monoxide under the foundation of the house. The first readings revealed carbon monoxide levels of 500 ppm in the basement. The contamination lasted for a week. The investigation indicated that the probable source of contamination was the use of explosives at a nearby rain sewer construction site. The use of explosives in a residential area can constitute a major source of carbon monoxide for the neighboring populations. This must be investigated, and public health authorities, primary-care physicians, governmental authorities, and users and manufacturers of explosives must be made aware of this problem.
Gloudemans, A.M.S.; Krol, M.C.; Meirink, J.F.; de Laat, A.T.J.; van der Werf, G.R.; Schrijver, H.; van den Broek, M.M.P.; Aben, I.
2006-01-01
The SCIAMACHY satellite instrument shows enhanced carbon monoxide (CO) columns in the Southern Hemisphere during the local Spring. Chemistry-transport model simulations using the new GFEDv2 biomass-burning emission database show a similar temporal and spatial CO distribution, indicating that the
Ambient carbon monoxide associated with alleviated respiratory inflammation in healthy young adults
International Nuclear Information System (INIS)
Zhao, Zhuohui; Chen, Renjie; Lin, Zhijing; Cai, Jing; Yang, Yingying; Yang, Dandan; Norback, Dan; Kan, Haidong
2016-01-01
There is increasing controversy on whether acute exposure to ambient carbon monoxide (CO) is hazardous on respiratory health. We therefore performed a longitudinal panel study to evaluate the acute effects of ambient CO on fractional exhaled nitric oxide (FeNO), a well-established biomarker of airway inflammation. We completed 4–6 rounds of health examinations among 75 healthy young adults during April to June in 2013 in Shanghai, China. We applied the linear mixed-effect model to investigate the short-term associations between CO and FeNO. CO exposure during 2–72 h preceding health tests was significantly associated with decreased FeNO levels. For example, an interquartile range increase (0.3 mg/m"3) of 2-h CO exposure corresponded to 10.6% decrease in FeNO. This association remained when controlling for the concomitant exposure to co-pollutants. This study provided support that short-term exposure to ambient CO might be related with reduced levels of FeNO, a biomarker of lower airway inflammation. - Highlights: • We completed 4–6 rounds of health examinations among 75 healthy young adults. • Short-term CO exposure was significantly associated with decreased FeNO levels. • The inverse association between CO and FeNO was robust controlling for co-pollutants. - Short-term exposure to ambient carbon monoxide may alleviate the respiratory inflammation.
40 CFR 86.1322-84 - Carbon monoxide analyzer calibration.
2010-07-01
... be used. (2) Zero the carbon monoxide analyzer with either zero-grade air or zero-grade nitrogen. (3... columns is one form of corrective action which may be taken.) (b) Initial and periodic calibration. Prior... calibrated. (1) Adjust the analyzer to optimize performance. (2) Zero the carbon monoxide analyzer with...
Varlet, Vincent; De Croutte, Emma Lagroy; Augsburger, Marc; Mangin, Patrice
2013-07-01
The aim of the study is to present the application of a headspace-gas chromatography-mass spectrometry (HS-GC-MS) method for the determination of the carbon monoxide (CO) blood concentration and to compare it with carboxyhemoglobin (HbCO) saturation. In postmortem cases, the HbCO measured by spectrophotometry frequently leads to inaccurate results due to inadequate samples or analyses. The true role of CO intoxication in the death of a person could be misclassified. The estimation of HbCO from HS-GC-MS CO measurements provides helpful information by determining the total CO levels (CO linked to hemoglobin (HbCO) and CO dissociated from hemoglobin). The CO concentrations were converted in HbCO saturation levels to define cutoff blood CO values. CO limits were defined as less than 1 μmol/mL for living persons, less than 1.5 μmol/mL for dead persons without CO exposure, and greater than 3 μmol/mL for dead persons with clear CO poisoning. © 2013 American Academy of Forensic Sciences.
Pathways and bioenergetics of anaerobic carbon monoxide fermentation
Diender, Martijn; Stams, Fons; Machado de Sousa, Diana
2015-01-01
Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the
Cui, Weiti; Qi, Fang; Zhang, Yihua; Cao, Hong; Zhang, Jing; Wang, Ren; Shen, Wenbiao
2015-03-01
Methane-rich water triggered adventitious rooting by regulating heme oxygenase1/carbon monoxide and calcium pathways in cucumber explants. Heme oxygenase1/carbon monoxide (HO1/CO) and calcium (Ca(2+)) were reported as the downstream signals in auxin-induced cucumber adventitious root (AR) formation. Here, we observed that application of methane-rich water (MRW; 80% saturation) obviously induced AR formation in IAA-depleted cucumber explants. To address the universality, we checked adventitious rooting in soybean and mung bean explants, and found that MRW (50 and 10% saturation, respectively) exhibited the similar inducing results. To further determine if the HO1/CO system participated in MRW-induced adventitious rooting, MRW, HO1 inducer hemin, its activity inhibitor zinc protoporphyrin IX (ZnPP), and its catalytic by-products CO, bilirubin, and Fe(2+) were used to detect their effects on cucumber adventitious rooting in IAA-depleted explants. Subsequent results showed that MRW-induced adventitious rooting was blocked by ZnPP and further reversed by 20% saturation CO aqueous solution. However, the other two by-products of HO1, bilirubin and Fe(2+), failed to induce AR formation. Above responses were consistent with the MRW-induced increases of HO1 transcript and corresponding protein level. Further molecular evidence indicted that expression of marker genes, including auxin signaling-related genes and cell cycle regulatory genes, were modulated by MRW alone but blocked by the cotreatment with ZnPP, the latter of which could be significantly rescued by the addition of CO. By using the Ca(2+)-channel blocker and Ca(2+) chelator, the involvement of Ca(2+) pathway in MRW-induced adventitious rooting was also suggested. Together, our results indicate that MRW might serve as a stimulator of adventitious rooting, which was partially mediated by HO1/CO and Ca(2+) pathways.
Occupational carbon monoxide violations in the State of Washington, 1994-1999.
Lofgren, Don J
2002-07-01
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
Carbon monoxide budget in the northern hemisphere
Energy Technology Data Exchange (ETDEWEB)
Bakwin, P.S.; Tans, P.P. (Climate Monitoring and Diagnostics Lab., Boulder, CO (United States)); Novelli, P.C. (Univ. of Colorado, Boulder, CO (United States))
1994-03-15
To improve urban air quality the major industrialized nations of the West took steps during the 1970s and 1980s to reduce carbon monoxide (CO) emissions from automobiles and other industrial sources. Overall, CO/CO[sub 2] emission ratios from the mix of fossil fuel combustion sources have been reduced by about half during 1976-1990. Also, the tropospheric abundance of hydroxyl radical (OH), which is the main sink for CO, is proposed to have increased globally by about 1.0 [+-] 0.8% yr[sup [minus]1]. The authors use a simple two-box model to examine the impact of shrinking emissions and increasing OH on the global abundance of CO. They find that these factors contribute about equally in reducing CO levels in the Northern Hemisphere troposphere by about 1.8 [+-] 0.8 ppb yr[sup [minus]1] on average. 19 refs., 1 fig.
Yuliusman; Afdhol, M. K.; Sanal, Alristo
2018-03-01
Carbon monoxide and methane gas are widely present in oil refineries. Off-potential gas is used as raw material for the petrochemical industry. In order for this off-gas to be utilized, carbon monoxide and methane must be removed from off-gas. This study aims to adsorb carbon monoxide and methane using activated carbon of palm shells and commercial activated carbon simultaneously. This research was conducted in 2 stages: 1) Preparation and characterization of activated carbon, 2) Carbon monoxide and methane adsorption test. The activation experiments using carbon dioxide at a flow rate of 150 ml/min yielded a surface area of 978.29 m2/g, Nitrogen at flow rate 150 ml/min yielded surface area 1241.48 m2/g, and carbon dioxide and nitrogen at a flow rate 200 ml/min yielded a surface area 300.37 m2/g. Adsorption of carbon monoxide and methane on activated carbon of palm shell systems yielded results in the amount of 0.5485 mg/g and 0.0649 mg/g and using commercial activated carbon yielded results in the amount of 0.5480 mg/g and 0.0650 mg/g
Exhaled carbon monoxide: a non-invasive biomarker of short-term exposure to outdoor air pollution
Directory of Open Access Journals (Sweden)
Herve Lawin
2017-04-01
Full Text Available Abstract Background In urban settings of Africa with rapidly increasing population, traffic-related air pollution is a major contributor to outdoor air pollution (OAP. Although OAP has been identified as a leading cause of global morbidity and mortality, there is however, lack of a simple biomarker to assess levels of exposure to OAP in resource-poor settings. This study evaluated the role of exhaled carbon monoxide (exhCO as a potential biomarker of exposure to ambient carbon monoxide (ambCO from OAP. Methods This was a descriptive study conducted among male commercial motorcycle riders in Cotonou – the economic capital of Benin. The participants’ AmbCO was measured using a portable carbon monoxide (CO data logger for 8 h during the period of their shift. ExhCO was measured just before and immediately after their shift (8-h Participants were asked not to cook or to smoke during the day of the measurements. Linear regression analysis was used to assess the association between ambCO and exhCO for the last 2, 4 and 6 h of their shift. Results Of 170 participants who completed the study, their mean ± SD age was 42.2 ± 8.4 years, and their mean ± SD daily income was 7.3 ± 2.7$. Also, 95% of the participants’ used solid fuels for cooking and only 2% had ever smoked. Average exhCO increased by 5.1 ppm at the end of the shift (p = 0.004. Post-shift exhCO was significantly associated to ambCO, this association was strongest for the last 2 h of OAP exposure before exhCO measurement (β = 0.34, p < 0.001. Conclusion ExhCO level was associated with recent exposure to ambCO from OAP with measurable increase after 8 h of exposure. These findings suggest that ExhCO may be a potential biomarker of short-term exposure to OAP.
Effect of Carbon Monoxide on Active Oxygen Metabolism of Postharvest Jujube
Shaoying Zhang; Qin Li; Yulan Mao
2014-01-01
To prolong the shelf life postharvest jujube, the effect of carbon monoxide (CO) on senescence of postharvest jujube in relation to active oxygen metabolism was investigated. Jujubes were fumigated with CO gas at 5, 10, 20 or 40μmol/L for 1 h, and then stored for 30 days at room temperature. Changes in membrane permeability, malonaldehyde (MDA), H2O2, O2•− content, and activities of active oxygen metabolism associated enzymes including superoxide dismutase (SOD), catalase (CAT) and peroxidase...
Diffusion-weighted MR imaging findings in carbon monoxide poisoning
International Nuclear Information System (INIS)
Teksam, M.; Casey, S.O.; Michel, E.; Liu, H.; Truwit, C.L.
2002-01-01
Diffusion-weighted MR imaging (DWI) of two patients with carbon monoxide (CO) poisoning demonstrated white matter and cortical hyperintensities. In one patient, the changes on the FLAIR sequence were more subtle than those on DWI. The DWI abnormality in this patient represented true restriction. In the second patient, repeated exposure to CO caused restricted diffusion. DWI may be helpful for earlier identification of the changes of acute CO poisoning. (orig.)
Atmospheric analyzer, carbon monoxide monitor and toluene diisocyanate monitor
Shannon, A. V.
1977-01-01
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.
Influence of cation size and surface coverage upon the infrared spectrum of carbon monoxide
Huang, Jimin
1991-01-01
Adsorbed carbon monoxide is utilized as a double layer probe molecule because of its strong absorption in infrared region and because of the high sensitivity of the carbon-oxygen bond to changes in the environment local to the electrode surface. Potential Difference Infrared Spectroscopy was used to investigate the structural behavior of CO adsorbed on a platinum electrode. Carbon monoxide was found to be exclusively linear-bonded on platinum electrode in the presence of tetran...
Health effects of carbon monoxide environmental pollution
Energy Technology Data Exchange (ETDEWEB)
1974-01-01
Carbon monoxide's (CO) chronic effects on man, its sources, and measuring methods are reviewed, and guidelines to determine health criteria are considered. The European data exchange included CO measuring methods in air and blood and their use in survey and experimental work, atmospheric CO pollution and sampling methods in urban thoroughfares and road tunnels in the European countries, a population survey of carboxyhemoglobin levels from cigarette smoking and atmospheric exposure, and physiological kinetics (uptake, distribution, and elimination) of CO inhalation. Additional topics are CO and the central nervous system, effects of moderate CO exposure on the cardiovascular system and on fetal development, and the current views on existing air quality criteria for CO.
Cavity-enhanced quantum-cascade laser-based instrument for carbon monoxide measurements.
Provencal, Robert; Gupta, Manish; Owano, Thomas G; Baer, Douglas S; Ricci, Kenneth N; O'Keefe, Anthony; Podolske, James R
2005-11-01
An autonomous instrument based on off-axis integrated cavity output spectroscopy has been developed and successfully deployed for measurements of carbon monoxide in the troposphere and tropopause onboard a NASA DC-8 aircraft. The instrument (Carbon Monoxide Gas Analyzer) consists of a measurement cell comprised of two high-reflectivity mirrors, a continuous-wave quantum-cascade laser, gas sampling system, control and data-acquisition electronics, and data-analysis software. CO measurements were determined from high-resolution CO absorption line shapes obtained by tuning the laser wavelength over the R(7) transition of the fundamental vibration band near 2172.8 cm(-1). The instrument reports CO mixing ratio (mole fraction) at a 1-Hz rate based on measured absorption, gas temperature, and pressure using Beer's Law. During several flights in May-June 2004 and January 2005 that reached altitudes of 41,000 ft (12.5 km), the instrument recorded CO values with a precision of 0.2 ppbv (1-s averaging time) and an accuracy limited by the reference CO gas cylinder (uncertainty < 1.0%). Despite moderate turbulence and measurements of particulate-laden airflows, the instrument operated consistently and did not require any maintenance, mirror cleaning, or optical realignment during the flights.
21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.
2010-04-01
... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-carbon monoxide copolymers. 177.1312... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1312 Ethylene-carbon monoxide copolymers. The ethylene-carbon monoxide copolymers identified in paragraph (a) of this section may be safely...
Directory of Open Access Journals (Sweden)
Gerrit Jan Schut
2016-01-01
Full Text Available Carbon monoxide (CO is an important intermediate in anaerobic carbon fixation pathways in acetogenesis and methanogenesis. In addition, some anaerobes can utilize CO as an energy source. In the hyperthermophilic archaeon Thermococcus onnurineus, which grows optimally at 80°C, CO oxidation and energy conservation is accomplished by a respiratory complex encoded by a 16-gene cluster containing a carbon monoxide dehydrogenase, a membrane-bound [NiFe]-hydrogenase and a Na+/H+ antiporter module. This complex oxidizes CO, evolves CO2 and H2, and generates a Na+ motive force that is used to conserve energy by a Na+-dependent ATP synthase. Herein we used a bacterial artificial chromosome to insert the 13.2 kb gene cluster encoding the CO-oxidizing respiratory complex of T. onnurineus into the genome of the heterotrophic archaeon, Pyrococcus furiosus, which grows optimally at 100°C. P. furiosus is normally unable to utilize CO, however, the recombinant strain readily oxidized CO and generated H2 at 80°C. Moreover, CO also served as an energy source and allowed the P. furiosus strain to grow with a limiting concentration of sugar or with peptides as the carbon source. Moreover, CO oxidation by P. furiosus was also coupled to the re-utilization, presumably for biosynthesis, of acetate generated by fermentation. The functional transfer of CO utilization between Thermococcus and Pyrococcus species demonstrated herein is representative of the horizontal gene transfer of an environmentally-relevant metabolic capability. The transfer of CO utilizing, hydrogen-producing genetic modules also has applications for biohydrogen production and a CO-based industrial platform for various thermophilic organisms.
Chen, Tsun-Ren; Wu, Fang-Siou; Lee, Hsiu-Pen; Chen, Kelvin H-C
2016-03-23
A pair of diiridium bimetallic complexes exhibit a special type of oxidation-reduction reaction that could directly split carbonate into carbon monoxide and molecular oxygen via a low-energy pathway needing no sacrificial reagent. One of the bimetallic complexes, Ir(III)(μ-Cl)2Ir(III), can catch carbonato group from carbonate and reduce it to CO. The second complex, the rare bimetallic complex Ir(IV)(μ-oxo)2Ir(IV), can react with chlorine to release O2 by the oxidation of oxygen ions with synergistic oxidative effect of iridium ions and chlorine atoms. The activation energy needed for the key reaction is quite low (∼20 kJ/mol), which is far less than the dissociation energy of the C═O bond in CO2 (∼750 kJ/mol). These diiridium bimetallic complexes could be applied as a redox switch to split carbonate or combined with well-known processes in the chemical industry to build up a catalytic system to directly split CO2 into CO and O2.
Ionin, Andrey; Kozlov, Andrey; Seleznev, Leonid; Sinitsyn, Dmitry
2008-10-01
Overtone lasing and fundamental band tuning was for the first time obtained in a carbon monoxide laser excited by repetitively pulsed capacitive slab RF discharge (81.36 MHz). RF discharge pulse repetition rate was 100--500 Hz. The active volume was 3x30x250 cubic mm. Laser electrodes were cooled down to 120 K. Gas mixture CO:air:He at gas pressure 15 Torr was used. The optical scheme ``frequency selective master oscillator - laser amplifier'' was applied for getting fundamental band tuning. Single line lasing with average power up to several tens of mW was observed on about 100 rotational-vibrational transitions of CO molecule within the spectral range 5.0--6.5 micron. Multiline overtone lasing was observed on about 80 spectral lines within the spectral range 2.5-4.0 micron, with maximum single line average output power 12 mW. The total output power of the slab overtone CO laser came up to 0.35 W, with laser efficiency 0.5 percent. The results of parametric studies of capacitive slab RF discharge in carbon monoxide mixtures, and overtone and fundamental band CO laser characteristics are discussed.
International Nuclear Information System (INIS)
Zhao, Yujie; Cao, Maoqi; Li, Yuquan; Shan, Xiaobin; Liu, Fuyi; Sheng, Liusi; Li, Li; Liu, Wanfang
2014-01-01
Highlights: • The high resolution photoionization spectrum of carbon monoxide has been investigated using tunable synchrotron radiation. • This work has investigated comprehensively almost all kinds of photo excitation processes of CO in wide photon region. • The mechanisms of photoionization and dissociative photoionization of CO have been researched in detail. - Abstract: The vacuum-ultraviolet photoionization and dissociative photoionization of carbon monoxide in a region 14–38 eV have been investigated with time-of-flight (TOF) photoionization mass spectrometry (PIMS) using tunable synchrotron radiation (SR). The adiabatic ionization energy (IE) of carbon monoxide and appearance energies (AE) for its fragment ions in different states are determined by measurements of photoionization efficiency spectra (PIES). Ab initio calculations have been performed to investigate the reaction mechanism of dissociative photoionization of carbon monoxide. On the basis of experimental and predicted theoretical results, the mechanisms of photoionization and dissociative photoionization of molecular CO are discussed, and sixteen dissociative photoionization processes are proposed. The equilibrium geometries and harmonic vibrational frequencies of CO molecule, and its parent cation were calculated by using MP2 (full) method. The differences of configurations between them are also discussed on the basis of theoretical calculations. According to our results, the experimental IE of CO molecule, and dissociation energies (E d ) of possible dissociative channels are in reasonable agreement with the calculated values of the proposed photodissociation channels
Carbon monoxide poisoning in Nigeria - it is time to pay attention ...
African Journals Online (AJOL)
Background: Carbon monoxide (CO) is a colourless, odourless gas and a cause of thousands of deaths across the world annually but its lethal consequences often go unrecognized, especially in developing countries. Aim: To discuss the subject of CO poisoning using local examples. Methods: Information was drawn from ...
Performance simulation of planar SOFC using mixed hydrogen and carbon monoxide gases as fuel
Energy Technology Data Exchange (ETDEWEB)
Inui, Y. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)]. E-mail: inui@eee.tut.ac.jp; Urata, A. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Ito, N. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Nakajima, T. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Tanaka, T. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)
2006-08-15
The authors investigate in detail the influence of the mixing ratio of hydrogen and carbon monoxide in the fuel on the cell performance of the SOFC through numerical simulations for a single cell plate of the co-flow type planar cell. It is made clear that the cell performance is almost the same and excellent, independent of the mixing ratio of hydrogen and carbon monoxide under the nominal operating condition. The electromotive force of the hydrogen rich fuel gas is a little higher than that of the carbon monoxide rich fuel gas. The internal voltage drop in the cell decreases as the fraction of carbon monoxide becomes high. Since the value of the single cell voltage is determined by the balance of these two phenomena, the lowering of the electromotive force is dominant and the single cell voltage of the hydrogen rich fuel gas is higher when the inlet gas temperature is high, whereas the voltage drop reduction is dominant and the single cell voltage of the carbon monoxide rich fuel gas is higher when the temperature is low. The effect of the additional gases of water vapor and carbon dioxide is restricted to the single cell voltage shift, and the qualitative dependence of the single cell voltage on the inlet gas temperature is determined by the mixing ratio of hydrogen and carbon monoxide.
Performance simulation of planar SOFC using mixed hydrogen and carbon monoxide gases as fuel
International Nuclear Information System (INIS)
Inui, Y.; Urata, A.; Ito, N.; Nakajima, T.; Tanaka, T.
2006-01-01
The authors investigate in detail the influence of the mixing ratio of hydrogen and carbon monoxide in the fuel on the cell performance of the SOFC through numerical simulations for a single cell plate of the co-flow type planar cell. It is made clear that the cell performance is almost the same and excellent, independent of the mixing ratio of hydrogen and carbon monoxide under the nominal operating condition. The electromotive force of the hydrogen rich fuel gas is a little higher than that of the carbon monoxide rich fuel gas. The internal voltage drop in the cell decreases as the fraction of carbon monoxide becomes high. Since the value of the single cell voltage is determined by the balance of these two phenomena, the lowering of the electromotive force is dominant and the single cell voltage of the hydrogen rich fuel gas is higher when the inlet gas temperature is high, whereas the voltage drop reduction is dominant and the single cell voltage of the carbon monoxide rich fuel gas is higher when the temperature is low. The effect of the additional gases of water vapor and carbon dioxide is restricted to the single cell voltage shift, and the qualitative dependence of the single cell voltage on the inlet gas temperature is determined by the mixing ratio of hydrogen and carbon monoxide
Ma, Ming; Trześniewski, Bartek J.; Xie, Jie; Smith, Wilson A.
2016-01-01
In this work, the selective electrocatalytic reduction of carbon dioxide to carbon monoxide on oxide-derived silver electrocatalysts is presented. By a simple synthesis technique, the overall high faradaic efficiency for CO production on the oxide-derived Ag was shifted by more than 400 mV towards a
Action of carbon monoxide on the affinity of hemoglobin for oxygen
Energy Technology Data Exchange (ETDEWEB)
Vanuxem, D.; Weiller, P.J.; Guillot, C.; Grimaud, C.
1982-01-01
The authors have studied the action of carbon monoxide on the affinity of hemoglobin for oxygen by measuring P50 in whole blood and in stripped hemoglobin before and after exposition of blood samples from heavy smokers and polycythemic patients with high levels of HbCO to hyperbaric oxygen (2.2 ata). The concentration of 2,3-diphosphoglycerate was normal although P50 was significantly lowered, not only in whole blood but also in stripped hemoglobin. Hyperbaric oxygen normalized P50 by removing CO radicals from stripped hemoglobin. This may indicate that CO radicals exert a direct action on the hemoglobin molecule, at least at the HbCO levels studied in this work.
Azieda Mohd Bakri, Nur; Junid, Syed Abdul Mutalib Al; Razak, Abdul Hadi Abdul; Idros, Mohd Faizul Md; Karimi Halim, Abdul
2015-11-01
Nowadays, the increasing level of carbon monoxide globally has become a serious environmental issue which has been highlighted in most of the country globally. The monitoring of carbon monoxide content is one of the approaches to identify the level of carbon monoxide pollution towards providing the solution for control the level of carbon monoxide produced. Thus, this paper proposed a mobile carbon monoxide monitoring system for measuring the carbon monoxide content based on Arduino-Matlab General User Interface (GUI). The objective of this project is to design, develop and implement the real-time mobile carbon monoxide sensor system and interfacing for measuring the level of carbon monoxide contamination in real environment. Four phases or stages of work have been carried out for the accomplishment of the project, which classified as sensor development, controlling and integrating sensor, data collection and data analysis. As a result, a complete design and developed system has been verified with the handheld industrial standard carbon monoxide sensor for calibrating the sensor sensitivity and measurement in the laboratory. Moreover, the system has been tested in real environments by measuring the level of carbon monoxide in three different lands used location; industrial area; residential area and main road (commercial area). In this real environment test, the industrial area recorded the highest reading with 71.23 ppm and 82.59 ppm for sensor 1 and sensor 2 respectively. As a conclusion, the mobile realtime carbon monoxide system based on the Arduino-Matlab is the best approach to measure the carbon monoxide concentration in different land-used since it does not require a manual data collection and reduce the complexity of the existing carbon monoxide level concentration measurement practise at the same time with a complete data analysis facilities.
Energy Technology Data Exchange (ETDEWEB)
Hibbert, D B; Tseung, A C.C.
1979-12-01
A study of the reduction of sulfur dioxide to elemental sulfur by carbon monoxide on a La/sub 0/ /sub 5/ Sr/sub 0/ /sub 5/ CoO/sub 3/ catalyst a perovskite oxide, to determine the effects of oxygen and water on SO2 reduction showed that in the presence of 5 to 16% oxygen, the reaction between sulfur dioxide and carbon monoxide still occurred if there was sufficient carbon monoxide in the gas to react with all the oxygen. At 600C, all the sulfur dioxide was removed at 5 to 16% oxygen levels. Water vapor at 2% did not adversely affect the reaction. The unwanted by-products, hydrogen disulfide and carbonyl sulfide, were reduced at contact times below 0.25 sec. During the reaction, the catalyst itself reacted with sulfur to give metal sulfides. When reagent grade CO/sub 2/O/sub 3/ was substituted for perovskite oxide, the maximum conversion of 98% of sulfur dioxide was attained at 550C, but an unacceptably high concentration of carbonyl sulfide was formed; within 1 hr, the sulfur dioxide conversion fell to 60%. The perovskite oxide reaction may be useful in removing sulfur dioxide from fosill fuel stack gases.
Reactivity of niobium cluster anions with nitrogen and carbon monoxide
Mwakapumba, Joseph; Ervin, Kent M.
1997-02-01
Reactions of small niobium cluster anions, Nbn-(n = 2-7), with CO and N2 are investigated using a flow tube reactor (flowing afterglow) apparatus. Carbon monoxide chemisorption on niobium cluster anions occurs with faster reaction rates than nitrogen chemisorption on corresponding cluster sizes. N2 addition to niobium cluster anions is much more size-selective than is CO addition. These general trends follow those reported in the literature for reactions of neutral and cationic niobium clusters with CO and N2. Extensive fragmentation of the clusters is observed upon chemisorption. A small fraction of the larger clusters survive and sequentially add multiple CO or N2 units without fragmentation. However, chemisorption saturation is not reached at the experimentally accessible pressure and reagent concentration ranges. The thermochemistry of the adsorption processes and the nature of the adsorbed species, molecular or dissociated, are discussed.
Turmuzi, M.; Suryati, I.; Mashaly, E. T.; Batubara, F.
2018-02-01
One source to decrease urban air ambient quality is transportation sector. Important pollutants are released by gas emissions from vehicles are carbon monoxide (CO), hydrocarbons (HC), nitrogen dioxide (NO2), particulate matter and others. The presence of CO pollutants in the ambient air can be predicted by modeling air quality. This study aims to estimate CO concentration resulting from transportation activities using Delhi Finite Line Source (DFLS) model, comparing CO prediction using a DFLS model with CO observation in the field, and determine the suitability of the DFLS model application on the MT Haryono street in Medan City. Research was conducted for 3 days at two sample points with frequency twice daily. Based on research results, the range of CO concentration from observation between 22.903 μg/m3 - 27.484 μg/m3. CO observation is still below the ambient air quality standard. According to the DFLS calculations, the range of CO concentration between 1.499 μg/m3- 2.051 μg/m3. The calculation index of agreement (IOA) validation test obtained value of d = 0.22. The DFLS model is not suitable to be applied on MT Haryono street because many factors affected such as wind direction and wind velocity, ambient air temperature and humidity
Directory of Open Access Journals (Sweden)
Katarzyna Magierowska
Full Text Available The physiological gaseous molecule, carbon monoxide (CO becomes a subject of extensive investigation due to its vasoactive activity throughout the body but its role in gastroprotection has been little investigated. We determined the mechanism of CO released from its donor tricarbonyldichlororuthenium (II dimer (CORM-2 in protection of gastric mucosa against 75% ethanol-induced injury. Rats were pretreated with CORM-2 30 min prior to 75% ethanol with or without 1 non-selective (indomethacin or selective cyclooxygenase (COX-1 (SC-560 and COX-2 (celecoxib inhibitors, 2 nitric oxide (NO synthase inhibitor L-NNA, 3 ODQ, a soluble guanylyl cyclase (sGC inhibitor, hemin, a heme oxygenase (HO-1 inductor or zinc protoporphyrin IX (ZnPPIX, an inhibitor of HO-1 activity. The CO content in gastric mucosa and carboxyhemoglobin (COHb level in blood was analyzed by gas chromatography. The gastric mucosal mRNA expression for HO-1, COX-1, COX-2, iNOS, IL-4, IL-1β was analyzed by real-time PCR while HO-1, HO-2 and Nrf2 protein expression was determined by Western Blot. Pretreatment with CORM-2 (0.5-10 mg/kg dose-dependently attenuated ethanol-induced lesions and raised gastric blood flow (GBF but large dose of 100 mg/kg was ineffective. CORM-2 (5 mg/kg and 50 mg/kg i.g. significantly increased gastric mucosal CO content and whole blood COHb level. CORM-2-induced protection was reversed by indomethacin, SC-560 and significantly attenuated by celecoxib, ODQ and L-NNA. Hemin significantly reduced ethanol damage and raised GBF while ZnPPIX which exacerbated ethanol-induced injury inhibited CORM-2- and hemin-induced gastroprotection and the accompanying rise in GBF. CORM-2 significantly increased gastric mucosal HO-1 mRNA expression and decreased mRNA expression for iNOS, IL-1β, COX-1 and COX-2 but failed to affect HO-1 and Nrf2 protein expression decreased by ethanol. We conclude that CORM-2 released CO exerts gastroprotection against ethanol-induced gastric
Campaign to prevent carbon monoxide poisoning : fall-winter 2007-2008
International Nuclear Information System (INIS)
Lefebvre, B.; Chabot, L.; Gratton, J.; Lacoursiere, D.
2009-01-01
Quebec launched a public health campaign for the Montreal region to prevent carbon monoxide poisoning. The objectives of the campaign were to communicate the dangers of carbon monoxide poisoning, its potential sources, its effects on public health, and the means to prevent poisoning. Its purpose was to inform the public of the risks and strategies to be used in case of carbon monoxide poisoning and to lay out the merits of household carbon monoxide alarms. The communication was done by way of the media, in cooperation with community organizations and school boards. Other tools used in the campaign included the Internet, flyers and press releases. A poll taken in 2008 showed that 59 per cent of the respondents had one or more sources for carbon monoxide in their homes, including fireplaces, and that 28 per cent had a functioning alarm for carbon monoxide detection. A future survey will be held to follow-up on the evolution of the campaign. The development of various activities will help decrease the risk of carbon monoxide poisoning. tabs., figs.
DEFF Research Database (Denmark)
Andersson, Mette F; Møller, Ann M
2010-01-01
Smoking increases perioperative complications. Carbon monoxide concentrations can estimate patients' smoking status and might be relevant in preoperative risk assessment. In smokers, we compared measurements of carbon monoxide in expired air (COexp) with measurements of carboxyhaemoglobin (COHb) ...
A Wireless and Batteryless Intelligent Carbon Monoxide Sensor.
Chen, Chen-Chia; Sung, Gang-Neng; Chen, Wen-Ching; Kuo, Chih-Ting; Chue, Jin-Ju; Wu, Chieh-Ming; Huang, Chun-Ming
2016-09-23
Carbon monoxide (CO) poisoning from natural gas water heaters is a common household accident in Taiwan. We propose a wireless and batteryless intelligent CO sensor for improving the safety of operating natural gas water heaters. A micro-hydropower generator supplies power to a CO sensor without battery (COSWOB) (2.5 W at a flow rate of 4.2 L/min), and the power consumption of the COSWOB is only ~13 mW. The COSWOB monitors the CO concentration in ambient conditions around natural gas water heaters and transmits it to an intelligent gateway. When the CO level reaches a dangerous level, the COSWOB alarm sounds loudly. Meanwhile, the intelligent gateway also sends a trigger to activate Wi-Fi alarms and sends notifications to the mobile device through the Internet. Our strategy can warn people indoors and outdoors, thereby reducing CO poisoning accidents. We also believe that our technique not only can be used for home security but also can be used in industrial applications (for example, to monitor leak occurrence in a pipeline).
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Carbon Monoxide Emission Limits for New... Pt. 60, Subpt. AAAA, Table 2 Table 2 to Subpart AAAA of Part 60—Carbon Monoxide Emission Limits for.... Compliance is determined by continuous emission monitoring systems. b Block averages, arithmetic mean. See...
A Review on Preferential Oxidation of Carbon Monoxide in Hydrogen Rich Gases
Directory of Open Access Journals (Sweden)
A. Mishra
2011-05-01
Full Text Available In this review, recent works on the preferential oxidation of carbon monoxide in hydrogen rich gases for fuel cell applications are summarized. H2 is used as a fuel for polymer-electrolyte membrane fuel cell (PEMFC. It is produced by reforming of natural gas or liquid fuels followed by water gas shift reaction. The produced gas consists of H2, CO, and CO2. In which CO content is around 1%, which is highly poisonous for the Pt anode of the PEMFC so that further removal of CO is needed. Catalytic preferential oxidation of CO (CO-PROX is one of the most suitable methods of purification of H2 because of high CO conversion rate at low temperature range, which is preferable for PEMFC operating conditions. Catalysts used for COPROX are mainly noble metal based; gold based and base metal oxide catalysts among them Copper-Ceria based catalysts are the most appropriate due to its low cost, easy availability and result obtained by these catalysts are comparable with the conventional noble metal catalysts. Copyright © 2011 BCREC UNDIP. All rights reserved(Received: 22nd October 2010, Revised: 12nd January 2011, Accepted: 19th January 2011[How to Cite: A. Mishra, R. Prasad. (2011. A Review on Preferential Oxidation of Carbon Monoxide in Hydrogen Rich Gases. Bulletin of Chemical Reaction Engineering & Catalysis, 6 (1: 1-14. doi:10.9767/bcrec.6.1.191.1-14][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.191.1-14 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/191] | View in
Geostatistical modelling of carbon monoxide levels in Khartoum State (Sudan) - GIS pilot based study
Energy Technology Data Exchange (ETDEWEB)
Alhuseen, A [Comenius University in Bratislava, Faculty of Natural Sciences, Dept. of Landscape Ecology, 84215 Bratislava (Slovakia); Madani, M [Ministry of Environment and Physical Development, 1111 Khartoum (Sudan)
2012-04-25
The objective of this study is to develop a digital GIS model; that can evaluate, predict and visualize carbon monoxide (CO) levels in Khartoum state. To achieve this aim, sample data had been collected, processed and managed to generate a dynamic GIS model of carbon monoxide levels in the study area. Parametric data collected from the field and analysis carried throughout this study show that (CO) emissions were lower than the allowable ambient air quality standards released by National Environment Protection Council (NEPC-USA) for 1998. However, this pilot study has found emissions of (CO) in Omdurman city were the highest. This pilot study shows that GIS and geostatistical modeling can be used as a powerful tool to produce maps of exposure. (authors)
Pathways and bioenergetics of anaerobic carbon monoxide fermentation.
Directory of Open Access Journals (Sweden)
Martijn eDiender
2015-11-01
Full Text Available Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the potential of converting CO rich gas, such as synthesis gas, into bio-based products. Three main types of fermentative CO metabolism can be distinguished: hydrogenogenesis, methanogenesis and acetogenesis, generating hydrogen, methane and acetate, respectively. Here, we review the current knowledge on these three variants of microbial CO metabolism with an emphasis on the potential enzymatic routes and bio-energetics involved.
Pathways and Bioenergetics of Anaerobic Carbon Monoxide Fermentation.
Diender, Martijn; Stams, Alfons J M; Sousa, Diana Z
2015-01-01
Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the potential of converting CO-rich gas, such as synthesis gas, into bio-based products. Three main types of fermentative CO metabolism can be distinguished: hydrogenogenesis, methanogenesis, and acetogenesis, generating hydrogen, methane and acetate, respectively. Here, we review the current knowledge on these three variants of microbial CO metabolism with an emphasis on the potential enzymatic routes and bio-energetics involved.
Pathology of carbon monoxide poisoning in two cats.
Sobhakumari, Arya; Poppenga, Robert H; Pesavento, J Brad; Uzal, Francisco A
2018-03-05
Carbon monoxide (CO), a common cause of poisoning in human beings has also been implicated in the death of animals. Though there are multiple studies on CO poisoning and relevant lethal blood COHb concentrations in humans, there are no reliable reports of diagnostic lethal carboxyhemoglobin percentage of saturation (COHb%) in cats. Additionally, due to shared housing environments, exposures to companion animals can be a surrogate for lethal exposures in human beings and provide valuable information in concurrent forensic investigations. Two adult Singapura brown ticked cats were submitted to the California Animal Health and Food Safety Laboratory (CAHFS) for necropsy and diagnostic work-up. These animals were found dead along with their two deceased owners. Similar lesions were observed in both cats. At necropsy, gross lesions consisted of multifocal, large, irregular, bright red spots on the skin of the abdomen and the inner surface of ear pinnae, bright red muscles and blood. The carcasses, and tissues fixed in formalin retained the bright red discoloration for up to two weeks. Microscopic lesions included diffuse pulmonary congestion and edema, and multifocal intense basophilia of cardiomyocytes mostly affecting whole fibers or occasionally a portion of the fiber. Based on the clinical history,gross and microscopic changes, cyanide or carbon monoxide poisoning was suspected. Blood samples analyzed for carbon monoxide showed 57 and 41% carboxyhemoglobin COHb%. Muscle samples were negative for cyanide. There are no established reference values for lethal COHb concentration in cats. The COHb % values detected in this case which fell within the lethal range reported for other species, along with the gross lesions and unique histological findings in the heart suggest a helpful criteria for diagnosis of CO intoxication associated death in cats. This case demonstrates that since pets share the same environment as human beings and often are a part of their activities
Comparison of measurement capability with 100 μmol/mol of carbon monoxide in nitrogen
Lee, Jeongsoon; Lee, JinBok; Lim, Jeongsik; Tarhan, Tanıl; Liu, Hsin-Wang; Aggarwal, Shankar G.
2018-01-01
Carbon monoxide (CO) in nitrogen was one of the first types of gas mixtures used in an international key comparison. The comparison dates back to 1998 (CCQMK1a) [1]. Since then, many National Metrology Institutes (NMIs) have developed calibration and measurement capabilities (CMCs) for these mixtures. Recently, NMIs in the APMP region have actively participated in international comparisons to provide domestic services. At the 2013 APMP meeting, several NMIs requested a CO comparison to establish CO/N2 certification for industrial applications, which was to be coordinated by KRISS. Consequently, this comparison provides an opportunity for APMP regional NMIs to develop CO/N2 CMC claims. The goal of this supplementary comparison is to support CMC claim for carbon monoxide in the N2 range of 50–2000 μmol/mol. An extended range may be supported as described in the GAWG strategy for comparisons and CMC claims. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Liu, Cong; Yin, Peng; Chen, Renjie; Meng, Xia; Wang, Lijun; Niu, Yue; Lin, Zhijing; Liu, Yunning; Liu, Jiangmei; Qi, Jinlei; You, Jinling; Kan, Haidong; Zhou, Maigeng
2018-01-01
Evidence of the acute health effects of ambient carbon monoxide air pollution in developing countries is scarce and mixed. We aimed to evaluate short-term associations between carbon monoxide and daily cardiovascular disease mortality in China. We did a nationwide time-series analysis in 272 major cities in China from January, 2013, to December, 2015. We extracted daily cardiovascular disease mortality data from China's Disease Surveillance Points system. Data on daily carbon monoxide concentrations for each city were obtained from the National Urban Air Quality Real-time Publishing Platform. City-specific associations between carbon monoxide concentrations and daily mortality from cardiovascular disease, coronary heart disease, and stroke were estimated with over-dispersed generalised linear models. Bayesian hierarchical models were used to obtain national and regional average associations. Exposure-response association curves and potential effect modifiers were evaluated. Two-pollutant models were fit to evaluate the robustness of the effects of carbon monoxide on cardiovascular mortality. The average annual mean carbon monoxide concentration in these cities from 2013 to 2015 was 1·20 mg/m 3 , ranging from 0·43 mg/m 3 to 2·45 mg/m 3 . For a 1 mg/m 3 increase in average carbon monoxide concentrations on the present day and previous day (lag 0-1), we observed significant increments in mortality of 1·12% (95% posterior interval [PI] 0·42-1·83) from cardiovascular disease, 1·75% (0·85-2·66) from coronary heart disease, and 0·88% (0·07-1·69) from stroke. These associations did not vary substantially by city, region, and demographic characteristics (age, sex, and level of education), and the associations for cardiovascular disease and coronary heart disease were robust to the adjustment of criteria co-pollutants. We did not find a threshold below which carbon monoxide exposure had no effect on cardiovascular disease mortality. This analysis is, to our
Forensic aspects of carbon monoxide poisoning by charcoal burning in Denmark, 2008-2012
DEFF Research Database (Denmark)
Nielsen, Pia Rude; Gheorghe, Alexandra; Lynnerup, Niels
2014-01-01
Carbon monoxide (CO) inhalation is a well-known method of committing suicide. There has been a drastic increase in suicide by inhalation of CO, produced from burning charcoal, in some parts of Asia, and a few studies have reported an increased number of these deaths in Europe. CO-related deaths c...
Energy Technology Data Exchange (ETDEWEB)
Gros, V.; Sarda-Esteve, R.; Bonsang, B.; Ramonet, M.
1998-09-01
Although carbon monoxide (CO) is present in trace quantities in the atmosphere (0.1 ppm -or parts per million in volume- on average), the study of this gas is important. Indeed, its impact on human can be dangerous at high level of concentration on the hand and it constitutes one of the main precursor of ozone in presence of concentration on the one hand and it constitutes one of the main precursor of ozone in presence of other pollutants on the other hand. Finally, CO affects the levels of several important greenhouse gases, through its reaction with hydroxyl radicals (OH). CO is measured in the atmosphere since the mid 60's by various methods. Among them, gas chromatography has the advantage to combine a low detection limit with a high precision. This report details the improvements made on the measurement analyser which allowed to perform automatic CO measurements in remote areas with low mixing ratios of carbon monoxide. This report describes some quality tests and the results of various applications. (authors)
Delayed encephalopathy after acute carbon monoxide poisoning
Directory of Open Access Journals (Sweden)
Mehmet İbrahim Turan
2014-03-01
Full Text Available Carbon monoxide poisoning is a major cause of death following attempted suicide and accidental exposures. Although clinical presentation depends on the duration and the intensity of exposure, the assessment of the severity of intoxication is difficult. A small percentage of patients who show complete initial recovery may develop delayed neurological deficits. Delayed encephalopathy after acute carbon monoxide poisoning is a rare and poor prognosis neurologic disorders and there is no specific treatment. We present a case with early onset of delayed encephalopathy after acute carbon monoxide poisoning with typical cranial imaging findings in a child with atypical history and clinical presentation.
Energy Technology Data Exchange (ETDEWEB)
Miura, Y; Yokoyama, H; Takahara, K; Miyamoto, K
1982-01-01
Long-term H/sub 2/ production by a thermophilic and heterocystous blue-green alga (cyanobacterium) Mastigocladus laminosus was studied under the conditions when acetylene and carbon monoxide were supplemented to the gas phase of the culture vessel. The addition of both gases enhanced H/sub 2/ evolution by nitrogen-starved cells. The concentrations of acetylene and carbon monoxide in the gas phase of argon/CO/sub 2/ (97.5/2.5) were 10% and 0.2 to 1%, respectively, for the maximum H/sub 2/ production. Renewals of the gas phase, in addition to the addition of acetylene and carbon monoxide, were necessary for durable H/sub 2/ production. Since the concentrations of both H/sub 2/ and O/sub 2/ accumulated in the gas phase were minimized after the renewals, the H/sub 2/ uptake activity, which was not completely inhibited by acetylene and carbon monoxide, was reduced and thereby H/sub 2/ evolution was restored. Under such conditions, H/sub 2/ production for up to 20 days was observed under argon and N/sub 2/ atmospheres with average rats of 3.9 and 3.3..mu..l/mg dry wt/h, respectively. H/sub 2/ evolution for 15 days was observed even under an air atmosphere containing acetylene and carbon monoxide. It was thus shown that prolonged production of H/sub 2/ was possible by the use of a blue-green alga which exhibits a high activity of H/sub 2/ uptake under nitrogen-starved conditions.
Autumn photoproduction of carbon monoxide in Jiaozhou Bay, China
Ren, Chunyan; Yang, Guipeng; Lu, Xiaolan
2014-06-01
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 μmol 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.
Senanayake, S D; Waterhouse, G I N; Idriss, H; Madey, Theodore E
2005-11-22
While coupling reactions of carbon-containing compounds are numerous in organometallic chemistry, they are very rare on well-defined solid surfaces. In this work we show that the reductive coupling of two molecules of carbon monoxide to C2 compounds (acetylene and ethylene) could be achieved on oxygen-defected UO2(111) single crystal and thin film surfaces. This result allows in situ electron spectroscopic investigation of a typical organometallic reaction such as carbon coupling and extends it to heterogeneous catalysis and solids. By using high-resolution photoelectron spectroscopy (HRXPS) it was possible to track the changes in surface states of the U and O atoms as well as identify the intermediate of the reaction. Upon CO adsorption U cations in low oxidation states are oxidized to U4+ ions; this was accompanied by an increase of the O-to-U surface ratios. The HRXPS C 1s lines show the presence of adsorbed species assigned to diolate species (-OCH=CHO-) that are most likely the reaction intermediate in the coupling of two CO molecules to acetylene and ethylene.
International Nuclear Information System (INIS)
Senanayake, S.; Waterhouse, G.; Idriss, H.; Madey, T.
2005-01-01
While coupling reactions of carbon-containing compounds are numerous in organometallic chemistry, they are very rare on well-defined solid surfaces. In this work we show that the reductive coupling of two molecules of carbon monoxide to C 2 compounds (acetylene and ethylene) could be achieved on oxygen-defected UO 2 (111) single crystal and thin film surfaces. This result allows in situ electron spectroscopic investigation of a typical organometallic reaction such as carbon coupling and extends it to heterogeneous catalysis and solids. By using high-resolution photoelectron spectroscopy (HRXPS) it was possible to track the changes in surface states of the U and O atoms as well as identify the intermediate of the reaction. Upon CO adsorption U cations in low oxidation states are oxidized to U 4+ ions; this was accompanied by an increase of the O-to-U surface ratios. The HRXPS C 1s lines show the presence of adsorbed species assigned to diolate species (-OCH=CHO-) that are most likely the reaction intermediate in the coupling of two CO molecules to acetylene and ethylene
The chest X-ray in pulmonary capillary haemorrhage: correlation with carbon monoxide uptake
International Nuclear Information System (INIS)
Bowley, N.B.; Hughes, J.M.B.; Steiner, R.E.
1979-01-01
Serial changes in carbon monoxide uptake (Ksub(CO) or Dsub(L)CO/VA) were used to monitor episodes of pulmonary capillary haemorrhage in Goodpasture's syndrome (13 cases), immune complex nephritis (three cases) and idiopathic haemosiderosis (one case). Air-space shadowing on the chest X-ray (on a scoring system 0 to 12) was assessed in the light of the changes of Ksub(CO). In 14 out of 27 episodes of bleeding, the rise and fall of Ksub(CO) was matched in time by the appearance and disappearance of air-space shadowing on the chest X-ray. In six episodes the chest X-ray remained normal despite a rise of Ksub(CO). In two cases air-space shadowing appeared up to 48 h after the rise of Ksub(CO). On five occasions chest X-ray abnormalities preceded the rise of Ksub(CO) but chest infection or fluid overload accounted for three of these. In cases with suspected pulmonary capillary haemorrhage, measurements of carbon monoxide uptake will provide additional information and will assist in the interpretation of the chest X-ray. (author)
Microbial fuel cell-based biosensor for toxic carbon monoxide monitoring
DEFF Research Database (Denmark)
Zhou, Shaofeng; Huang, Shaobin; Li, Yi
2018-01-01
This study presents an innovative microbial fuel cell-based biosensor for carbon monoxide (CO) monitoring. The hypothesis for the function of the biosensor is that CO inhibits bacterial activity in the anode and thereby reduces electricity production. A mature electrochemically active biofilm...... increasing CO concentration over 70%. Besides, the response time of the biosensor was 1 h. The compact design and simple operation of the biosensor makes it easy to be integrated in existing CO-based industrial facilities either as a forewarning sensor for CO toxicity or even as an individual on...
Solar cycle variations in mesospheric carbon monoxide
Lee, Jae N.; Wu, Dong L.; Ruzmaikin, Alexander; Fontenla, Juan
2018-05-01
As an extension of Lee et al. (2013), solar cycle variation of carbon monoxide (CO) is analyzed with MLS observation, which covers more than thirteen years (2004-2017) including maximum of solar cycle 24. Being produced primarily by the carbon dioxide (CO2) photolysis in the lower thermosphere, the variations of the mesospheric CO concentration are largely driven by the solar cycle modulated ultraviolet (UV) variation. This solar signal extends down to the lower altitudes by the dynamical descent in the winter polar vortex, showing a time lag that is consistent with the average descent velocity. To characterize a global distribution of the solar impact, MLS CO is correlated with the SORCE measured total solar irradiance (TSI) and UV. As high as 0.8 in most of the polar mesosphere, the linear correlation coefficients between CO and UV/TSI are more robust than those found in the previous work. The photochemical contribution explains most (68%) of the total variance of CO while the dynamical contribution accounts for 21% of the total variance at upper mesosphere. The photochemistry driven CO anomaly signal is extended in the tropics by vertical mixing. The solar cycle signal in CO is further examined with the Whole Atmosphere Community Climate Model (WACCM) 3.5 simulation by implementing two different modeled Spectral Solar Irradiances (SSIs): SRPM 2012 and NRLSSI. The model simulations underestimate the mean CO amount and solar cycle variations of CO, by a factor of 3, compared to those obtained from MLS observation. Different inputs of the solar spectrum have small impacts on CO variation.
40 CFR 51.241 - Nonattainment areas for carbon monoxide and ozone.
2010-07-01
... Intergovernmental Consultation Agency Designation § 51.241 Nonattainment areas for carbon monoxide and ozone. (a... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Nonattainment areas for carbon monoxide and ozone. 51.241 Section 51.241 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...
The effect of carbon monoxide on planetary haze formation
Energy Technology Data Exchange (ETDEWEB)
Hörst, S. M.; Tolbert, M. A, E-mail: sarah.horst@colorado.edu [Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO (United States)
2014-01-20
Organic haze plays a key role in many planetary processes ranging from influencing the radiation budget of an atmosphere to serving as a source of prebiotic molecules on the surface. Numerous experiments have investigated the aerosols produced by exposing mixtures of N{sub 2}/CH{sub 4} to a variety of energy sources. However, many N{sub 2}/CH{sub 4} atmospheres in both our solar system and extrasolar planetary systems also contain carbon monoxide (CO). We have conducted a series of atmosphere simulation experiments to investigate the effect of CO on the formation and particle size of planetary haze analogues for a range of CO mixing ratios using two different energy sources, spark discharge and UV. We find that CO strongly affects both number density and particle size of the aerosols produced in our experiments and indicates that CO may play an important, previously unexplored, role in aerosol chemistry in planetary atmospheres.
Energy Technology Data Exchange (ETDEWEB)
Sokal, J.A.; Majka, J.; Palus, J.
1984-12-01
Tissue carbon monoxide (CO) content was investigated in rats severely intoxicated with CO under various exposure conditions: 1% CO for 4 min, 0.4% CO for 40 min and 0.12% CO for 12 h. Extravascular CO was determined in the heart and skeletal muscles immediately after termination of exposure, and carboxymyoglobin (MbCO) percent saturation was calculated. Total brain CO was estimated immediately after termination of exposure and after the time periods of restitution. After the same exposure conditions, MbCO percent saturation was higher in the heart than in skeletal muscle. In both types of muscle, saturation on myoglobin (Mb) with CO depended on blood carboxyhemoglobin (HbCO) level and not on the duration of exposure. The time course of CO elimination was the same for blood and brain, irrespective of CO exposure conditions. The results obtained showed that acute CO intoxication induced by long duration exposures did not involve CO accumulation in the tissues.
UV-induced carbon monoxide emission from living vegetation
DEFF Research Database (Denmark)
Bruhn, Dan; Albert, Kristian Rost; Mikkelsen, Teis Nørgaard
2013-01-01
The global burden of carbon monoxide (CO) is rather uncertain. In this paper we address the potential for UV-induced CO emission by living terrestrial vegetation surfaces. Real-time measurements of CO concentrations were made with a cavity enhanced laser spectrometer connected in closed loop...... to either an ecosystem chamber or a plant-leaf scale chamber. Leaves of all examined plant species exhibited emission of CO in response to artificial UV-radiation as well as the UV-component of natural solar radiation. The UV-induced rate of CO emission exhibited a rather low dependence on temperature......, indicating an abiotic process. The emission of CO in response to the UV-component of natural solar radiation was also evident at the ecosystem scale....
Carbon Monoxide Information Center
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International Nuclear Information System (INIS)
Maennistoe, J.; Puustinen, T.; Uotila, P.
1985-01-01
Cigarette smoke is known to interfere with the pulmonary metabolism of arachidomic acid and prostaglandin E 2 (PGE 2 ). We investigated the possible role of carbon monoxide in these cigarette smoke-infuced alterations. 4 C-Arachidonic acid (50 nmol) was indused into the pulmonary circulation of isolated perfused hamster lungs and the radioactive metabolites in the perfusion effluent, as well as the distribution of incorporated radioactive arachidonic acid within the lung lipids, were analysed. Carbon monoxide, added into the ventilatory air, had no effect on the oxidative metabolism of arachidonic acid or on the distribution of radioactive arachidonic acid within the lung. In addition, carbon monoxide had no effect on the metabolism of PGE 2 following infusion of 100 nmol of 14 C-PGE 2 into the rat pulmonary circulation. The present study suggests that carbon monoxide is not responsible for the cigarette smoke-induced changes in the pulmonary metabolism of arachidonic acid and PGE 2 . (author)
Oxygen permeation flux through La1-ySryFeO3 limited by the carbon monoxide oxidation rate
van Hassel, B.A.; van Hassel, B.A.; ten Elshof, Johan E.; Bouwmeester, Henricus J.M.
1995-01-01
The oxygen permeation flux through La1-ySryFeO3-δ (y = 0.1, 0.2) in a large oxygen partial pressure gradient (air/CO, CO2 mixture) was found to be limited by the carbon monoxide oxidation rate at the low oxygen partial pressure side of the membrane. The oxygen permeation flux through the membrane
High Resolution Spectra of Carbon Monoxide, Propane and Ammonia for Atmospheric Remote Sensing
Beale, Christopher Andrew
Experiment satellite of carbon monoxide. The effect of the atmosphere's chemistry and physics on this molecule is measured through its isotopologues, primarily 13CO (carbon-13 substituted carbon monoxide). Isotopic chemistry allows a key analysis of the atmosphere as it may be used as a tracer for chemical reactions and dynamical processes. The carbon monoxide fractionation results in Chapter IV present the first global measurements of isotopic fractionation of CO, showing significant fractionation in the upper atmosphere (60-80 km) as a result of the photolysis of carbon dioxide (CO2).
Fetal brain damage following maternal carbon monoxide intoxication: an experimental study
Energy Technology Data Exchange (ETDEWEB)
Ginsberg, M D; Myers, R E
1974-01-01
Techniques of fetal monitoring, including fetal blood sampling in utero, were employed to study the physiological effects of acute maternal carbon monoxide intoxication on nine term-pregnant female rhesus monkeys exposed to 0.1 to 0.3% inspired carbon monoxide over 1 to 3 hr. The mothers tolerated carboxyhemoglobin levels exceeding 60% without clinical sequelae, whereas the fetuses promptly developed profound hypoxia upon exposure of the mothers to CO. The fetal COHb levels rose only gradually over 1 to 3 hr, and thus contributed only slightly to the development of early fetal hypoxia. The fetal hypoxia was associated with bradycardia, hypotension, and metabolic and respiratory acidosis. Severity of intrauterine hypoxia was closely correlated with the appearance of brain damage. Brain swelling associated with hemorrhagic necrosis of the cerebral hemispheres (severe brain damage) appeared only in fetuses whose arterial oxygen content was reduced below 1.0 ml/100 ml for at least 45 min during the maternal CO intoxication.
DEFF Research Database (Denmark)
Gang, Xiao; Li, Qingfeng; Hjuler, Hans Aage
1995-01-01
Hydrogen oxidation has been studied on a carbon-supported platinum gas diffusion electrode in a phosphoric acidelectrolyte in the presence of carbon monoxide and oxygen in the feed gas. The poisoning effect of carbon monoxide presentin the feed gas was measured in the temperature range from 80...... to 150°C. It was found that throughout the temperaturerange, the potential loss due to the CO poisoning can be reduced to a great extent by the injection of small amounts ofgaseous oxygen into the hydrogen gas containing carbon monoxide. By adding 5 volume percent (v/o) oxygen, an almost...
SEASONAL SOIL FLUXES OF CARBON MONOXIDE IN BURNED AND UNBURNED BRAZILIAN SAVANNAS
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...
Carbon Monoxide Nonattainment Areas
U.S. Environmental Protection Agency — This data layer identifies areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standards (NAAQS) for Carbon Monoxide and have...
Optimization of Treatment Policy for Acute Carbon Monoxide Poisoning
Directory of Open Access Journals (Sweden)
R. N. Akalayev
2012-01-01
Full Text Available Objective: to evaluate the efficiency of combination use of hyperbaric oxygenation, succinate-containing solutions, and anti-edematous agents in patients with acute carbon monoxide poisoning. Subjects and methods. The results of treatment were analyzed in 32 patients admitted in 2009—2011 for severe acute carbon monoxide poisoning and a Glasgow coma score of 6—8. The patients were divided into 2 groups: 1 patients whose combination therapy involved hyperbaric oxygenation, Succinasol infusions, and L-lysine-aescinate injections; 2 those who received traditional therapy. All the patients underwent complex clinical, laboratory, and neurophysiologic examinations. Results. Just 24 hours after the combination use of Succinasol and L-lysine-aescinate, Group I patients were observed to have substantially reduced lactate, the content of the latter approached the normal value following 48 hours, which was much below the values in the control group. The similar pattern was observed when endogenous intoxication parameters were examined. During the performed therapy, the level of consciousness and that of intellect according to the MMSE and FAB scales were restored more rapidly in the study group patients than in Group 2. Conclusion. The combination use of hyperbaric oxygenation, the succinate-containing solution Succinasol, and the anti-edematous agent L-lysine-aescinate considerably enhances the efficiency of intensive therapy for acute carbon monoxide poisoning. Key words: carbon monoxide, toxic hypoxic encephalopathy, combination therapy, hyperbaric oxygenation, succinic acid, L-lysine-aescinate.
Carbon Monoxide Information Center
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Bio-Inspired Carbon Monoxide Sensors with Voltage-Activated Sensitivity
Savagatrup, Suchol
2017-09-27
Carbon monoxide (CO) outcompetes oxygen when binding to the iron center of hemeproteins, leading to a reduction in blood oxygen level and acute poisoning. Harvesting the strong specific interaction between CO and the iron porphyrin provides a highly selective and customizable sensor. We report the development of chemiresistive sensors with voltage-activated sensitivity for the detection of CO comprising iron porphyrin and functionalized single-walled carbon nanotubes (F-SWCNTs). Modulation of the gate voltage offers a predicted extra dimension for sensing. Specifically, the sensors show a significant increase in sensitivity toward CO when negative gate voltage is applied. The dosimetric sensors are selective to ppm levels of CO and functional in air. UV/Vis spectroscopy, differential pulse voltammetry, and density functional theory reveal that the in situ reduction of FeIII to FeII enhances the interaction between the F-SWCNTs and CO. Our results illustrate a new mode of sensors wherein redox active recognition units are voltage-activated to give enhanced and highly specific responses.
Forgotten carbon: indirect CO2 in greenhouse gas emission inventories
International Nuclear Information System (INIS)
Gillenwater, Michael
2008-01-01
National governments that are Parties to the United Nations Framework Convention on Climate Change (UNFCCC) are required to submit greenhouse gas (GHG) inventories accounting for the emissions and removals occurring within their geographic territories. The Intergovernmental Panel on Climate Change (IPCC) provides inventory methodology guidance to the Parties of the UNFCCC. This methodology guidance, and national inventories based on it, omits carbon dioxide (CO 2 ) from the atmospheric oxidation of methane, carbon monoxide, and non-methane volatile organic compounds emissions that result from several source categories. The inclusion of this category of 'indirect' CO 2 in GHG inventories increases global anthropogenic emissions (excluding land use and forestry) between 0.5 and 0.7%. However, the effect of inclusion on aggregate UNFCCC Annex I Party GHG emissions would be to reduce the growth of total emissions, from 1990 to 2004, by 0.2% points. The effect on the GHG emissions and emission trends of individual countries varies. The paper includes a methodology for calculating these emissions and discusses uncertainties. Indirect CO 2 is equally relevant for GHG inventories at other scales, such as global, regional, organizational, and facility. Similarly, project-based methodologies, such as those used under the Clean Development Mechanism, may need revising to account for indirect CO 2
Ma, Mingyan; Noei, Heshmat; Mienert, Bernd; Niesel, Johanna; Bill, Eckhard; Muhler, Martin; Fischer, Roland A; Wang, Yuemin; Schatzschneider, Ulrich; Metzler-Nolte, Nils
2013-05-17
Crystals of MIL-88B-Fe and NH2-MIL-88B-Fe were prepared by a new rapid microwave-assisted solvothermal method. High-purity, spindle-shaped crystals of MIL-88B-Fe with a length of about 2 μm and a diameter of 1 μm and needle-shaped crystals of NH2-MIL-88B-Fe with a length of about 1.5 μm and a diameter of 300 nm were produced with uniform size and excellent crystallinity. The possibility to reduce the as-prepared frameworks and the chemical capture of carbon monoxide in these materials was studied by in situ ultrahigh vacuum Fourier-transform infrared (UHV-FTIR) spectroscopy and Mössbauer spectroscopy. CO binding occurs to unsaturated coordination sites (CUS). The release of CO from the as-prepared materials was studied by a myoglobin assay in physiological buffer. The release of CO from crystals of MIL-88B-Fe with t(1/2) = 38 min and from crystals of NH2-MIL-88B-Fe with t(1/2) = 76 min were found to be controlled by the degradation of the MIL materials under physiological conditions. These MIL-88B-Fe and NH2-MIL-88B-Fe materials show good biocompatibility and have the potential to be used in pharmacological and therapeutic applications as carriers and delivery vehicles for the gasotransmitter carbon monoxide. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Marisa R. Myers
2017-12-01
Full Text Available The presence of hydrated salts on Mars indicates that some regions of its surface might be habitable if suitable metabolizable substrates are available. However, several lines of evidence have shown that Mars’ regolith contains only trace levels of the organic matter needed to support heterotrophic microbes. Due to the scarcity of organic carbon, carbon monoxide (CO at a concentration of about 700 parts per million (about 0.4 Pa might be the single most abundant readily available substrate that could support near-surface bacterial activity. Although a variety of electron acceptors can be coupled to CO oxidation, perchlorate is likely the most abundant potential oxidant in Mars’ brines. Whether perchlorate, a potent chaotrope, can support microbial CO oxidation has not been previously documented. We report here the first evidence for perchlorate-coupled CO oxidation based on assays with two distinct euryarchaeal extreme halophiles. CO oxidation occurred readily in 3.8 M NaCl brines with perchlorate concentrations from 0.01 to 1 M. Both isolates were able to couple CO with perchlorate or chlorate under anaerobic conditions with or without nitrate as an inducer for nitrate reductase, which serves as a perchlorate reductase in extreme halophiles. In the presence of perchlorate, CO concentrations were reduced to levels well below those found in Mars’ atmosphere. This indicates that CO could contribute to the survival of microbial populations in hydrated salt formations or brines if water activities are suitably permissive.
CO 2-scrubbing and methanation as purification system for PEFC
Ledjeff-Hey, K.; Roes, J.; Wolters, R.
Hydrogen is usually produced by steam reforming of natural gas in large-scale processes. The reformate consists of hydrogen, carbon dioxide, carbon monoxide, and residues of hydrocarbons. Since the anode catalyst of a polymer electrolyte membrane fuel cell (PEFC) is usually based on platinum, which is easily poisoned by carbon monoxide, the conditioned feed gas should contain less than 100 ppmv CO, and preferably, less than 10 ppmv. Depending on the design and operating conditions of the hydrogen production process, the CO content of a typical reformate gas, even after the CO shift reactor may be in the range of 0.2-1.0 vol.%; this is far higher than a PEFC can tolerate. A CO management system is required to lower the CO concentration to acceptable levels. In many cases, the CO purification system consists of a combination of physical or chemical processes to achieve the necessary reduction in CO content. A promising alternative for hydrogen purification is a combined process consisting of a carbon dioxide scrubber with subsequent methanation to reduce the carbon monoxide content to an acceptable level of less than 10 ppmv.
Analysis of patients presenting to the emergency department with carbon monoxide intoxication
Directory of Open Access Journals (Sweden)
Selim Yurtseven
2015-12-01
Full Text Available Objectives: Carbon monoxide is a potentially fatal form of poisoning. The exact incidence is unclear, due to cases being undiagnosed or reported as fewer than the real number. Hyperbaric oxygen therapy (HBOT is of proven efficacy in the treatment of CO intoxication.The purpose of this study was to describe the general characteristics of carbon monoxide (CO intoxications presenting to the emergency department and to investigate troponin I values and the effectiveness of hyperbaric oxygen therapy (HBOT in these patients. Material and methods: Patients presenting to the emergency department with CO intoxication over one year and patients with such intoxications receiving HBOT were examined retrospectively. Results: One hundred seventy-one patients were included; 140 (81.9% were poisoned by stoves, 18 (10.5% by hot water boilers and 10 in (5.8% by fires. COHb levels were normal in 49 of the 163 patients whose values were investigated, and were elevated in 114 patients. Mean COHb value was 16.6. Troponin I values were investigated in 112 patients. These were normal in 86 patients and elevated in 26. Mean troponin I value was 0.38 ng/ml. One hundred twenty-three of the 171 patients in the study were discharged in a healthy condition after receiving normobaric oxygen therapy, while 48 patients received HBOT. Forty-two (87.5% of the patients receiving HBOT were discharged in a healthy condition while sequelae persisted in five (10.4%. One patient died after 15 session of HBOT. Conclusion: Although elevated carboxyhemoglobin confirms diagnosis of CO intoxication, normal levels do not exclude it. Troponin I levels may rise in CO intoxication. No significant relation was observed between carboxyhemoglobin and receipt of HBOT. A significant correlation was seen, however, between troponin I levels and receipt of HBOT. Keywords: Carbon monoxide intoxication, Hyperbaric oxygen, Troponin I, Echocardiography
Directory of Open Access Journals (Sweden)
Arvand Haschemi
Full Text Available Carbon monoxide (CO dampens pro-inflammatory responses in a peroxisome proliferator-activated receptor-γ (PPARγ and p38 mitogen-activated protein kinase (MAPK dependent manner. Previously, we demonstrated that CO inhibits lipopolysaccharide (LPS-induced expression of the proinflammatory early growth response-1 (Egr-1 transcription factor in macrophages via activation of PPARγ. Here, we further characterize the molecular mechanisms by which CO modulates the activity of PPARγ and Egr-1 repression. We demonstrate that CO enhances SUMOylation of PPARγ which we find was attributed to mitochondrial ROS generation. Ectopic expression of a SUMOylation-defective PPARγ-K365R mutant partially abolished CO-mediated suppression of LPS-induced Egr-1 promoter activity. Expression of a PPARγ-K77R mutant did not impair the effect of CO. In addition to PPARγ SUMOylation, CO-activated p38 MAPK was responsible for Egr-1 repression. Blocking both CO-induced PPARγ SUMOylation and p38 activation, completely reversed the effects of CO on inflammatory gene expression. In primary macrophages isolated form C57/BL6 male mice, we identify mitochondrial ROS formation by CO as the upstream trigger for the observed effects on Egr-1 in part through uncoupling protein 2 (UCP2. Macrophages derived from bone marrow isolated from Ucp2 gene Knock-Out C57/BL6 mice (Ucp2(-/-, produced significantly less ROS with CO exposure versus wild-type macrophages. Moreover, absence of UCP2 resulted in a complete loss of CO mediated Egr-1 repression. Collectively, these results indentify p38 activation, PPARγ-SUMOylation and ROS formation via UCP2 as a cooperative system by which CO impacts the inflammatory response.
The RCK1 high-affinity Ca2+ sensor confers carbon monoxide sensitivity to Slo1 BK channels.
Hou, Shangwei; Xu, Rong; Heinemann, Stefan H; Hoshi, Toshinori
2008-03-11
Carbon monoxide (CO) is a lethal gas, but it is also increasingly recognized as a physiological signaling molecule capable of regulating a variety of proteins. Among them, large-conductance Ca(2+)- and voltage-gated K(+) (Slo1 BK) channels, important in vasodilation and neuronal firing, have been suggested to be directly stimulated by CO. However, the molecular mechanism of the stimulatory action of CO on the Slo1 BK channel has not been clearly elucidated. We report here that CO reliably and repeatedly activates Slo1 BK channels in excised membrane patches in the absence of Ca(2+) in a voltage-sensor-independent manner. The stimulatory action of CO on the Slo1 BK channel requires an aspartic acid and two histidine residues located in the cytoplasmic RCK1 domain, and the effect persists under the conditions known to inhibit the conventional interaction between CO and heme in other proteins. We propose that CO acts as a partial agonist for the high-affinity divalent cation sensor in the RCK1 domain of the Slo1 BK channel.
Carbon Monoxide Information Center
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Effect of vegetation in reducing carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Kimura, J C
1977-01-01
Carbon monoxide is a product of incomplete combustion. Because almost all of this gas is produced by motor vehicles, it is considered to have a line rather than a stationary point source. Greatest concentrations of this lethal gas correspond to periods of peak traffic volume and congestion; therefore, there are two daily periods of maxima and minima. Carbon monoxide cannot be detected by sight or smell. For this reason, this gas is especially deadly. During the summer of 1975, a study involving carbon monoxide concentrations at selected sites in Sendai was undertaken in conjunction with an ongoing investigation of urban pollution under the directorship of Professor Toshio Noh of Tohoku University. This study was made possible by a grant from the Japan Society for the Promotion of Science. 5 references, 5 figures, 1 table.
Wu, Martin; Ren, Qinghu; Durkin, A Scott; Daugherty, Sean C; Brinkac, Lauren M; Dodson, Robert J; Madupu, Ramana; Sullivan, Steven A; Kolonay, James F; Haft, Daniel H; Nelson, William C; Tallon, Luke J; Jones, Kristine M; Ulrich, Luke E; Gonzalez, Juan M; Zhulin, Igor B; Robb, Frank T; Eisen, Jonathan A
2005-11-01
We report here the sequencing and analysis of the genome of the thermophilic bacterium Carboxydothermus hydrogenoformans Z-2901. This species is a model for studies of hydrogenogens, which are diverse bacteria and archaea that grow anaerobically utilizing carbon monoxide (CO) as their sole carbon source and water as an electron acceptor, producing carbon dioxide and hydrogen as waste products. Organisms that make use of CO do so through carbon monoxide dehydrogenase complexes. Remarkably, analysis of the genome of C. hydrogenoformans reveals the presence of at least five highly differentiated anaerobic carbon monoxide dehydrogenase complexes, which may in part explain how this species is able to grow so much more rapidly on CO than many other species. Analysis of the genome also has provided many general insights into the metabolism of this organism which should make it easier to use it as a source of biologically produced hydrogen gas. One surprising finding is the presence of many genes previously found only in sporulating species in the Firmicutes Phylum. Although this species is also a Firmicutes, it was not known to sporulate previously. Here we show that it does sporulate and because it is missing many of the genes involved in sporulation in other species, this organism may serve as a "minimal" model for sporulation studies. In addition, using phylogenetic profile analysis, we have identified many uncharacterized gene families found in all known sporulating Firmicutes, but not in any non-sporulating bacteria, including a sigma factor not known to be involved in sporulation previously.
Directory of Open Access Journals (Sweden)
2005-11-01
Full Text Available We report here the sequencing and analysis of the genome of the thermophilic bacterium Carboxydothermus hydrogenoformans Z-2901. This species is a model for studies of hydrogenogens, which are diverse bacteria and archaea that grow anaerobically utilizing carbon monoxide (CO as their sole carbon source and water as an electron acceptor, producing carbon dioxide and hydrogen as waste products. Organisms that make use of CO do so through carbon monoxide dehydrogenase complexes. Remarkably, analysis of the genome of C. hydrogenoformans reveals the presence of at least five highly differentiated anaerobic carbon monoxide dehydrogenase complexes, which may in part explain how this species is able to grow so much more rapidly on CO than many other species. Analysis of the genome also has provided many general insights into the metabolism of this organism which should make it easier to use it as a source of biologically produced hydrogen gas. One surprising finding is the presence of many genes previously found only in sporulating species in the Firmicutes Phylum. Although this species is also a Firmicutes, it was not known to sporulate previously. Here we show that it does sporulate and because it is missing many of the genes involved in sporulation in other species, this organism may serve as a "minimal" model for sporulation studies. In addition, using phylogenetic profile analysis, we have identified many uncharacterized gene families found in all known sporulating Firmicutes, but not in any non-sporulating bacteria, including a sigma factor not known to be involved in sporulation previously.
Directory of Open Access Journals (Sweden)
Martin Wu
2005-11-01
Full Text Available We report here the sequencing and analysis of the genome of the thermophilic bacterium Carboxydothermus hydrogenoformans Z-2901. This species is a model for studies of hydrogenogens, which are diverse bacteria and archaea that grow anaerobically utilizing carbon monoxide (CO as their sole carbon source and water as an electron acceptor, producing carbon dioxide and hydrogen as waste products. Organisms that make use of CO do so through carbon monoxide dehydrogenase complexes. Remarkably, analysis of the genome of C. hydrogenoformans reveals the presence of at least five highly differentiated anaerobic carbon monoxide dehydrogenase complexes, which may in part explain how this species is able to grow so much more rapidly on CO than many other species. Analysis of the genome also has provided many general insights into the metabolism of this organism which should make it easier to use it as a source of biologically produced hydrogen gas. One surprising finding is the presence of many genes previously found only in sporulating species in the Firmicutes Phylum. Although this species is also a Firmicutes, it was not known to sporulate previously. Here we show that it does sporulate and because it is missing many of the genes involved in sporulation in other species, this organism may serve as a "minimal" model for sporulation studies. In addition, using phylogenetic profile analysis, we have identified many uncharacterized gene families found in all known sporulating Firmicutes, but not in any non-sporulating bacteria, including a sigma factor not known to be involved in sporulation previously.
The study on catalytic performance of CuO/CexZr1-xO2 catalyst in carbon monoxide oxidation
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Huang Jinhua
2017-12-01
Full Text Available A series of CuO/CexZr1-xO2 samples were prepared by incipient-wetness impregnation method with CexZr1-xO2 used as the catalyst carrier which was synthesized by co-precipitation method.The influences of the mass ratio of CeO2:ZrO2 and CuO loading were investigated using catalytic activity test,XRD,BET,H2-TPR,and CO-TPR techniques.The results revealed that with a CeO2:ZrO2 mass ratio of 4:1 and 10% CuO loading,10%CuO/Ce0.815Zr0.185O2 catalyst showed a larger surface area and pore volume,a higher dispersity of CuO particles,better reduction property and CO oxidation property.Thus,10% CuO/Ce0.815Zr0.185O2 catalyst exhibited a high catalytic activity in the carbon monoxide oxidation with 100% CO conversion at the temperature as low as 80℃ under atmospheric pressure.
Gene expression in rat striatum following carbon monoxide poisoning
Directory of Open Access Journals (Sweden)
Shuichi Hara
2017-06-01
Full Text Available Carbon monoxide (CO poisoning causes brain damage, which is attenuated by treatment with hydrogen [1,2], a scavenger selective to hydroxyl radical (·≡OH [3]. This suggests a role of ·≡OH in brain damage due to CO poisoning. Studies have shown strong enhancement of ·≡OH production in rat striatum by severe CO poisoning with a blood carboxyhemoglobin (COHb level >70% due to 3000 ppm CO, but not less severe CO poisoning with a blood COHb level at approximately 50% due to 1000 ppm CO [4]. Interestingly, 5% O2 causes hypoxia comparable with that by 3000 ppm CO and produces much less •OH than 3000 ppm CO does [4]. In addition, cAMP production in parallel with ·≡OH production [5] might contribute to ·≡OH production [6]. It is likely that mechanisms other than hypoxia contribute to brain damage due to CO poisoning [7]. To search for the mechanisms, we examined the effects of 1000 ppm CO, 3000 ppm CO and 5% O2 on gene expression in rat striatum. All array data have been deposited in the Gene Expression Omnibus (GEO database under accession number GSE94780.
A Southern Hemisphere atmospheric history of carbon monoxide from South Pole firn air
Verhulst, K. R.; Aydin, M.; Novelli, P. C.; Holmes, C. D.; Prather, M. J.; Saltzman, E. S.
2013-12-01
Carbon monoxide (CO) is a reactive trace gas and is important to tropospheric photochemistry as a major sink of hydroxyl radicals (OH). Major sources of CO are fossil fuel combustion, linked mostly to automotive emissions, biomass burning, and oxidation of atmospheric methane. Understanding changes in carbon monoxide over the past century will improve our understanding of man's influence on the reactivity of the atmosphere. Little observational information is available about CO levels and emissions prior to the 1990s, particularly for the Southern Hemisphere. The NOAA global flask network provides the most complete instrumental record of CO, extending back to 1988. Annually averaged surface flask measurements suggest atmospheric CO levels at South Pole were relatively stable from 2004-2009 at about 51 nmol mol-1 [Novelli and Masarie, 2013]. In this study, a 20th century atmospheric history of CO is reconstructed from South Pole firn air measurements, using a 1-D firn air diffusion model. Firn air samples were collected in glass flasks from two adjacent holes drilled from the surface to 118 m at South Pole, Antarctica during the 2008/2009 field season and CO analysis was carried out by NOAA/CCG. Carbon monoxide levels increase from about 45 nmol mol-1 in the deepest firn sample at 116 m to 52 nmol mol-1 at 107 m, and remain constant at about 51-52 nmol mol-1 at shallower depths. Atmospheric histories based on the firn air reconstructions suggest that CO levels over Antarctica increased by roughly 40% (from about 36 to 50 nmol mol-1) between 1930-1990, at a rate of about 0.18 nmol mol-1 yr-1. Firn air and surface air results suggest the rate of CO increase at South Pole slowed considerably after 1990. The firn air-based atmospheric history is used to infer changes in Southern Hemisphere CO emissions over the 20th century.
Energy Technology Data Exchange (ETDEWEB)
1989-03-01
This bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include carbon monoxide binding affinity studies with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels as related to tobacco and marijuana smoke, occupational exposure and the NIOSH biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (This updated bibliography contains 221 citations, 19 of which are new entries to the previous edition.)
Carbon monoxide exposure and information processing during perceptual-motor performance
Energy Technology Data Exchange (ETDEWEB)
Mihevic, P.M.; Gliner, J.A.; Horvath, S.M.
1983-01-01
This study examined the influence of exposure to ambient carbon monoxide resulting in final carboxyhemoglobin (COHb) levels of approximately 5.0% on the ability to process information during motor performance. Subjects (n . 16) performed a primary reciprocal tapping task and a secondary digit manipulation task singly and/or concurrently during 2.5 h exposure to room air (0 ppm CO) or 100 ppm CO. Five levels of tapping difficulty and two levels of digit manipulation were employed. Tapping performance was unaffected when COHb levels were as high as 5%. However, at this level of COHb it was noted that CO exposure interacted with task difficulty of both tasks to influence reaction time on the digit manipulation task. It was concluded that motor performance was not influenced by exposure to CO leading to COHb concentrations of 5%. Task difficulty was a significant factor mediating behavioral effects of CO exposure.
Carbon monoxide exposure and information processing during perceptual-motor performance
Energy Technology Data Exchange (ETDEWEB)
Mihevic, P.M.; Gliner, J.A.; Horvath, S.M.
1983-04-01
This study examined the influence of exposure to ambient carbon monoxide resulting in final carboxyhemoglobin (COHb) levels of approximately 5.0% on the ability to process information during motor performance. Subjects (n = 16) performed a primary reciprocal tapping task and a secondary digit manipulation task singly and/or concurrently during 2.5 h exposure to room air (0 ppm CO) or 100 ppm CO. Five levels of tapping difficulty and two levels of digit manipulation were employed. Tapping performance was unaffected when COHb levels were as high as 5%. However, at this level of COHb it was noted that CO exposure interacted with task difficulty of both tasks to influence reaction time on the digit manipulation task. It was concluded that motor performance was not influenced by exposure to CO leading to COHb concentrations of 5%. Task difficulty was a significant factor mediating behavioral effects of CO exposure.
Carbon Monoxide Information Center
Full Text Available ... Investigations Associated with Non-Fire Carbon Monoxide from Engine-Driven Generators and Other Engine-Driven Tools, 2004–2014 JANUARY 08, 2015 Non- ... outside of the Federal Government. CPSC does not control this external site or its privacy policy and ...
Carbon Monoxide: An Essential Signalling Molecule
Mann, Brian E.
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).
Influence of carbon monoxide to the surface layer of uranium metal and its oxides
International Nuclear Information System (INIS)
Wang Xiaoling; Fu Yibei; Xie Renshou; Huang Ruiliang
1996-09-01
The surface structures of uranium metal and triuranium octaoxide (U 3 O 8 ) and the influence of carbon monoxide to the surface layers have been studied by X-ray photoelectron spectroscopy (XPS). After exposure to carbon monoxide, contents of oxygen in the surface oxides of uranium metal and U 3 O 8 are decreased and O/U ratios decrease 7.2%, 8.0% respectively. The investigation indicated the surface layers of uranium metal and its oxides were forbidden to further oxidation in the atmosphere of carbon monoxide. (11 refs., 9 figs., 2 tabs.)
Carbon Monoxide Distribution over Peninsular Malaysia from the Atmospheric Infrared Sounder (AIRS)
Rajab, Jaso M.; MatJafri, M. Z.; Lim, H. S.; Abdullah, K.
2009-07-01
The Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua satellite. It daily coverage of ˜70% of the planet represents a significant evolutionary advance in satellite traces gas remote sensing. AIRS, the part of a large international investment to upgrade the operational meteorological satellite systems, is first of the new generation of meteorological advanced sounders for operational and research use, Providing New Insights into Weather and Climate for the 21st Century. Carbon monoxide (CO) is a ubiquitous, an indoor and outdoor air pollutant, is not a significant greenhouse gas as it absorbs little infrared radiation from the Earth. However, it does have an influence on oxidization in the atmosphere through interaction with hydroxyl radicals (OH), which also react with methane, halocarbons and tropospheric ozone. It produced by the incomplete combustion of fossil fuels and biomass burning, and that it has a role as a smog. The aim of this investigation is to study the (CO) carbon monoxide distribution over Peninsular Malaysia. The land use map of the Peninsular Malaysia was conducted by using CO total column amount, obtained from AIRS data, the map & data was processed and analyzed by using Photoshop & SigmaPlot 11.0 programs and compared for timing of various (day time) (28 August 2005 & 29 August 2007) for both direct comparison and the comparison using the same a priori profile, the CO concentrations in 28/8/2005 higher. The CO maps were generated using Kriging Interpolation technique. This interpolation technique produced high correlation coefficient, R2 and low root mean square error, RMS for CO. This study provided useful information for influence change of CO concentration on varies temperature.
Polyketones as alternating copolymers of carbon monoxide
International Nuclear Information System (INIS)
Belov, Gennady P; Novikova, Elena V
2004-01-01
Characteristic features of the catalytic synthesis of alternating copolymers of carbon monoxide with various olefins, dienes, styrene and its derivatives are considered. The diversity of catalyst systems used for the copolymerisation of carbon monoxide is demonstrated and their influence on the structure and the molecular mass of the resulting copolymers is analysed. The data on the structure and physicochemical and mechanical properties of this new generation of functional copolymers are generalised and described systematically for the first time.
Hearing Loss due to Carbon Monoxide Poisoning
DEFF Research Database (Denmark)
Mehrparvar, Amir Houshang; Davari, Mohammad Hossein; Mollasadeghi, Abolfazl
2013-01-01
Carbon monoxide poisoning is one of the rare causes of hearing loss which may cause reversible or irreversible, unilateral or bilateral hearing loss after acute or chronic exposure. In this report, we present a case of bilateral sensorineural hearing loss in a secondary smelting workshop worker...... after an acute exposure to carbon monoxide. This complication was diagnosed by pure-tone audiometry and confirmed by transient evoked otoacoustic emissions. Hearing loss has not improved after 3 months of followup....
An interesting cause of pulmonary emboli: Acute carbon monoxide poisoning
Energy Technology Data Exchange (ETDEWEB)
Sevinc, A.; Savli, H.; Atmaca, H. [Gaziantep University, Gaziantep (Turkey). School of Medicine
2005-07-01
Carbon monoxide poisoning, a public health problem of considerable significance, is a relatively frequent event today, resulting in thousands of hospitalizations annually. A 70-year-old lady was seen in the emergency department with a provisional diagnosis of carbon monoxide poisoning. The previous night, she slept in a tightly closed room heated with coal ember. She was found unconscious in the morning with poor ventilation. She had a rare presentation of popliteal vein thrombosis, pulmonary emboli, and possible tissue necrosis with carbon monoxide poisoning. Oxygen treatment with low-molecular-weight heparin (nadroparine) and warfarin therapy resulted in an improvement in both popliteal and pulmonary circulations. In conclusion, the presence of pulmonary emboli should be sought in patients with carbon monoxide poisoning.
Integrated Science Assessment (ISA) for Carbon Monoxide (Second External Review Draft, Sep 2009)
EPA announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes was made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evaluation of t...
An Unusual Cause of Supraventricular Tachycardia: Acute Carbon Monoxide Poisoning
Directory of Open Access Journals (Sweden)
Suat Zengin
2014-03-01
Full Text Available Carbon monoxide (CO is a toxic gas produced by the incomplete combustion of carbon-containing compounds. Exposure to high concentrations of CO can be letha and is the most common cause of death from poisoning worldwide. Cardiac manifestations after exposure to CO, including myocardial ischemia, heart failure, and arrhythmias, have been reported. A 28-year-old a patient was admitted to our emergency department with altered consciousness as a consequence of acute domestic exposure to CO from a stove. His carboxyhemoglobin level was 39%. The oxygen treatment was started promptly, and therapeutic red cell exchange was performed. An electrocardiogram revealed supraventricular tachycardia (SVT, and an echocardiographic examination demonstrated normal cardiac functions. To the best of our knowledge, this study is the second to report a case of SVT attack due to acute CO intoxication. This paper discusses the management of this complication in patients poisoned with CO.
International Nuclear Information System (INIS)
Wong, T.T.T.; Sachtler, W.M.H.; Stakheev, A.Yu.
1992-01-01
This paper uses x-ray photoelectron spectroscopy, fourier transform infrared spectroscopy and temperature programmed mass-spectrometric analysis to study the interaction of Na-Y supported rhodium with hydrogen, carbon monoxide, and zeolite protons. This report attempts to clarify the mechanism of dispersive oxidation of reduced Rh particles in the presence of CO, leading to the formation of Rh + (CO) 2 cations
Analysis of carbon monoxide production in multihundred-watt heat sources
International Nuclear Information System (INIS)
Peterson, D.E.; Mulford, R.N.R.
1976-05-01
The production of carbon monoxide observed within Multihundred Watt heat sources placed under storage conditions was analyzed. Results of compositional and isotopic analyses of gas taps performed on eight heat sources are summarized and interpreted. Several proposed CO generation mechanisms are examined theoretically and assessed by applying thermodynamic principles. Outgassing of the heat source graphite followed by oxygen isotopic exchange through the vent assemblies appears to explain the CO production at storage temperatures. Reduction of the plutonia fuel sphere by the CO is examined as a function of temperature and stoichiometry. Experiments that could be performed to investigate possible CO generation mechanisms are discussed
DEFF Research Database (Denmark)
Andersson, Mette F; Møller, Ann M
2010-01-01
Smoking increases perioperative complications. Carbon monoxide concentrations can estimate patients' smoking status and might be relevant in preoperative risk assessment. In smokers, we compared measurements of carbon monoxide in expired air (COexp) with measurements of carboxyhaemoglobin (COHb) ......) in arterial blood. The objectives were to determine the level of correlation and to determine whether the methods showed agreement and evaluate them as diagnostic tests in discriminating between heavy and light smokers....
Energy Technology Data Exchange (ETDEWEB)
1990-03-01
This bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include carbon monoxide binding affinity studies with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels as related to tobacco and marijuana smoke, occupational exposure and the NIOSH biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (This updated bibliography contains 237 citations, 16 of which are new entries to the previous edition.)
Carbon monoxide exposure in households in Ciudad Juárez, México.
Montoya, Teresa; Gurian, Patrick L; Velázquez-Angulo, Gilberto; Corella-Barud, Verónica; Rojo, Analila; Graham, Jay P
2008-03-01
This study assessed exposure to carbon monoxide from gas and wood heater emissions in a sample of 64 households in peri-urban residential areas in Ciudad Juárez, Chihuahua, México. Indoor and outdoor carbon monoxide concentrations and temperatures were monitored for a continuous period of 1 week at 1 and 6-min intervals, respectively. The moving average carbon monoxide concentrations were compared to the World Health Organization (WHO) standards for carbon monoxide. Sixty-seven percent of households with gas heaters and 60% of households with wood heaters exceeded a health-based standard at some point during the monitoring. The difference between indoor and outdoor temperatures was modestly correlated with average carbon monoxide exposure (r=0.35, p-value h standard of 9ppm (odds ratio=5.1, p-value=0.031). These results highlight the need for further efforts to identify and mitigate potentially hazardous carbon monoxide exposures, particularly in moderate-income countries with cooler climates.
Shindell, D.T.; Krol, M.C.
2006-01-01
We analyze present-day and future carbon monoxide (CO) simulations in 26 state-ofthe- art atmospheric chemistry models run to study future air quality and climate change. In comparison with near-global satellite observations from the MOPITT instrument and local surface measurements, the models show
Electrocardiographic Findings and Serum Troponin I in Carbon Monoxide Poisoned Patients
Directory of Open Access Journals (Sweden)
Scott Reza Jafarian Kerman
2012-03-01
Full Text Available Carbon monoxide (CO poisoning, though with different sources, is one of the most deadly emergencies in all countries. CO can threaten men's life by several paths especially cardiac complications, which can mimic other cardiac problems such as myocardial infarction. The objective of this study was to determine ECG findings and serum troponin I levels in CO poisoned patients. In this analytical cross-sectional study, 63 CO poisoning patients were consecutively included from hospital's emergency departments. CO content was measured by a CO-oximeter and an electrocardiography was taken first thing on admission. Arterial blood gas (ABG, troponin I and other data was collected afterwards. Data were divided by age groups (adults and children and gender. CO content was significantly higher only in subjects with normal T wave compared to patients with inverted T wave in their initial ECG (P=0.016. No other significant difference was noticed. None of the ABG findings correlated significantly with CO content. Also no significant correlation was found with CO content after stratification by gender and age groups, but pH in children (r=-0.484, P=0.026. CO content was significantly higher in adults (P=0.023, but other ABG data were not significantly different. Only 3 patients had elevated troponin I. Receiver operating characteristic (ROC analysis showed no significant cutoff points in CO content for ECG changes. No significant specific change in electrocardiograms (ECG could contribute carboxyhemoglobin content in carbon monoxide poisoned patients. In addition, no specific difference was found between adults and pediatric subjects' ECGs. All other findings seemed to be accidental.
Residential carbon monoxide poisoning from motor vehicles.
Hampson, Neil B
2011-01-01
Although morbidity and mortality from accidental carbon monoxide (CO) poisoning are high in the United States, identification of common but poorly recognized sources should help prevention efforts. The study aimed to describe CO poisoning of home occupants due to a vehicle left running in an attached garage. News stories reporting incidents of US CO poisoning were collected daily from March 2007 to September 2009 via a news.Google.com search and data extracted. Patients were individuals reported in the media to have been poisoned with CO in their home by a vehicle running in the attached garage. Main outcome measures were frequency of occurrence, geographic distribution, patient demographics, and mortality. Of 837 CO poisoning incidents reported in US news media over 2 and a half years, 59 (8%) were the result of a vehicle left running in the garage. The elderly were disproportionately affected, with incidents most common in states with larger elderly populations and 29% of cases with age specified occurring in individuals older than 80 years. Among those older than 80 years, 15 of 17 were found dead at the scene. Residential CO poisoning from a vehicle running in the garage is common, disproportionately affects the elderly, has a high mortality rate, and should be preventable with a residential CO alarm. Copyright © 2011 Elsevier Inc. All rights reserved.
Mechanism of obtaining carbon monoxide and hydrogen during brown coal radiolysis. [Gamma radiation
Energy Technology Data Exchange (ETDEWEB)
Rustamov, V R; Kurbanov, M A; Dzantiev, B T; Kerimov, V K; Musaeva, P F
1982-05-01
This article analyzes effects of gamma radiation on the yield of products of coal gasification: hydrogen and carbon monoxide. Samples of brown coal from the Kansk-Achins basin were treated by gamma radiation with cobalt 60 radiation source. Analyses show that accumulation of hydrogen and carbon monoxide in brown coal under influence of gamma radiation is characterized by a constant rate. Yields of carbon monoxide and hydrogen amount to 0.16 molecule/100 electro volt and 0.21 molecule/electro volt respectively. Reducing radiation dose from 2.5 to 0.7 millirad/h reduces yields of hydrogen and carbon monoxide. Increasing temperature of vacuum brown coal pyrolysis from 200 to 600 C causes decrease of hydrogen yield. Hydrogen yield decrease during temperature increase is caused by a high content of aromatic nuclei in the samples used in the radiolysis. (5 refs.)
Carbon monoxide activation via O-bound CO using decamethylscandocinium-hydridoborate ion pairs.
Berkefeld, Andreas; Piers, Warren E; Parvez, Masood; Castro, Ludovic; Maron, Laurent; Eisenstein, Odile
2012-07-04
Ion pairs [Cp*(2)Sc](+)[HB(p-C(6)F(4)R)(3)](-) (R = F, 1-F; R = H, 1-H) were prepared and shown to be unreactive toward D(2) and α-olefins, leading to the conclusion that no back-transfer of hydride from boron to scandium occurs. Nevertheless, reaction with CO is observed to yield two products, both ion pairs of the [Cp*(2)Sc](+) cation with formylborate (2-R) and borataepoxide (3-R) counteranions. DFT calculations show that these products arise from the carbonyl adduct of the [Cp*(2)Sc](+) in which the CO is bonded to scandium through the oxygen atom, not the carbon atom. The formylborate 2-R is formed in a two-step process initiated by an abstraction of the hydride by the carbon end of an O-bound CO, which forms an η(2)-formyl intermediate that adds, in a second step, the borane at the carbon. The borataepoxide 3-R is suggested to result from an isomerization of 2-R. This unprecedented reaction represents a new way to activate CO via a reaction channel emanating from the ephemeral isocarbonyl isomer of the CO adduct.
Wang, Yejun; Kulatilaka, Waruna D.
2018-01-01
Ultrashort-pulse, femtosecond (fs)-duration, two-photon laser-induced fluorescence (fs-TPLIF) measurements of carbon monoxide (CO) are reported in rich, sooting hydrocarbon flames. CO-TPLIF detection using conventional nanosecond or picosecond lasers are often plagued by photochemical interferences, specifically under fuel-rich flames conditions. In the current study, we investigate the commonly used CO two-photon excitation scheme of the B1Σ+ ← X1Σ+ electronic transition, using approximately 100-fs-duration excitation pulses. Fluorescence emission was observed in the Ångström band originating from directly populated B1Σ+ upper state, as well as, in the third positive band from collisionally populated b3Σ+ upper state. The current work was focused on the Ångström band emission. Interference from nascent C2 emissions originating from hot soot particles in the flame could be reduced to a negligible level using a narrower detection gate width. In contrast, avoiding interferences from laser-generated C2 Swan-band emissions required specific narrowband spectral filtering in sooting flame conditions. The observed less than quadratic laser pulse energy dependence of the TPLIF signal suggests the presence of strong three-photon ionization and stimulated emission processes. In a range of CH4/air and C2H4/air premixed flames investigated, the measured CO fluorescence signals agree well with the calculated equilibrium CO number densities. Reduced-interference CO-TPLIF imaging in premixed C2H4/O2/N2 jet flames is also reported.
Elevated carboxyhemoglobin: sources of carbon monoxide exposure.
Buchelli Ramirez, Herminia; Fernández Alvarez, Ramón; Rubinos Cuadrado, Gemma; Martinez Gonzalez, Cristina; Rodriguez Jerez, Francisco; Casan Clara, Pere
2014-11-01
Inhalation of carbon monoxide (CO) can result in poisoning, with symptoms ranging from mild and nonspecific to severe, or even death. CO poisoning is often underdiagnosed because exposure to low concentrations goes unnoticed, and threshold values for normal carboxyhemoglobin vary according to different authors. The aim of our study was to analyze carboxyhemoglobin (COHb) levels in an unselected population and detect sources of CO exposure In a cross-sectional descriptive study, we analyzed consecutive arterial blood gas levels processed in our laboratory. We selected those with COHb≥2.5% in nonsmokers and ≥5% in smokers. In these cases a structured telephone interview was conducted. Elevated levels of COHb were found in 64 (20%) of 306 initial determinations. Of these, data from 51 subjects aged 65±12 years, 31 (60%) of which were men, were obtained. Mean COHb was 4.0%. Forty patients (78%) were non-smokers with mean COHb of 3.2%, and 11 were smokers with COHb of 6.7%. In 45 patients (88.2%) we detected exposure to at least one source of ambient CO other than cigarette smoke. A significant proportion of individuals from an unselected sample had elevated levels of COHb. The main sources of CO exposure were probably the home, so this possibility should be explored. The population should be warned about the risks and encouraged to take preventive measures. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.
Shindell, D.T.; Faluvegi, G.; Stevenson, D.S.; Krol, M.C.; Emmons, L.K.; Lamarque, J.F.; Petron, G.; Dentener, F.J.; Ellingsen, K.; Schultz, M.G.; Wild, O.; Amann, M.; Atherton, C.S.; Bergmann, D.J.; Bey, I.; Butler, T.; Cofala, J.; Collins, W.J.; Derwent, R.G.; Doherty, R.M.; Drevet, J.; Eskes, H.J.; Fiore, A.M.; Gauss, M.; Hauglustaine, D.A.; Horowitz, L.W.; Isaksen, I.S.A.; Lawrence, M.G.; Montanaro, V.; Muller, J.F.; Pitari, G.; Prather, M.J.; Pyle, J.A.; Rast, S.; Rodriguez, J.M.; Sanderson, M.G.; Savage, N.H.; Strahan, S.E.; Sudo, K.; Szopa, S.; Unger, N.; Noije, van T.P.C.; Zeng, G.
2006-01-01
We analyze present-day and future carbon monoxide (CO) simulations in 26 state-of-the-art atmospheric chemistry models run to study future air quality and climate change. In comparison with near-global satellite observations from the MOPITT instrument and local surface measurements, the models show
The relation between carbon monoxide emission and visual extinction in cloud L134
International Nuclear Information System (INIS)
Tucker, K.D.; Dickman, R.L.; Encrenaz, P.J.; Kutner, M.L.
1976-01-01
Emission from the J=1→0 transition of carbon monoxide has been mapped over an area of 40' x 55' in cloud L134, and visual extinctions over the entire cloud have been obtained by means of star counts. Line intensities of > or =2 K are observable down to an extinction level of about one magnitude. From observations of the J=1→0 transition of the 13 CO isotopic species at 18 locations in the cloud, we have found a linear correlation between the local thermodynamic equilibrium (LTE) column densities of 13 CO and magnitudes of visual extinction
Zhang, Yong; Xie, Huixiang; Fichot, CéDric G.; Chen, Guohua
2008-12-01
We investigated the thermal (dark) production of carbon monoxide (CO) from dissolved organic matter (DOM) in the water column of the St. Lawrence estuarine system in spring 2007. The production rate, Qco, decreased seaward horizontally and downward vertically. Qco exhibited a positive, linear correlation with the abundance of chromophoric dissolved organic matter (CDOM). Terrestrial DOM was more efficient at producing CO than marine DOM. The temperature dependence of Qco can be characterized by the Arrhenius equation with the activation energies of freshwater samples being higher than those of salty samples. Qco remained relatively constant between pH 4-6, increased slowly between pH 6-8 and then rapidly with further rising pH. Ionic strength and iron chemistry had little influence on Qco. An empirical equation, describing Qco as a function of CDOM abundance, temperature, pH, and salinity, was established to evaluate CO dark production in the global coastal waters (depth carbon from CO a-1). We speculated the global oceanic (coastal plus open ocean) CO dark production to be in the range from 4.87 to 15.8 Tg CO-C a-1 by extrapolating the coastal water-based results to blue waters (depth > 200 m). Both the coastal and global dark source strengths are significant compared to the corresponding photochemical CO source strengths (coastal: ˜2.9 Tg CO-C a-1; global: ˜50 Tg CO-C a-1). Steady state deepwater CO concentrations inferred from Qco and microbial CO uptake rates are <0.1 nmol L-1.
Electrocatalytic oxidation of carbon monoxide
Directory of Open Access Journals (Sweden)
Manuel de Jesus Santiago Farias
2009-01-01
Full Text Available Este trabalho discute alguns aspectos importantes relacionados à reação de eletrooxidação do monóxido de carbono sobre monocristais de platina, em meio ácido. Aspectos mecanísticos são discutidos em termos da formação das estruturas compactas que o CO forma quando este é adsorvido. As principais idéias aqui apresentadas, levam em consideração as existências dessas estruturas. Os clássicos mecanismos Lagmuir-Hinshelwood e Eley-Rideal são aqui discutidos, especialmente o primeiro considerando a mobilidade do CO e também a nucleação e crescimento de ilhas formadas por espécies adsorvidas contendo oxigênio.////////// This work discusses some important aspects related to the carbon monoxide electrooxidation reaction on Pt single crystal electrodes in acidic media. The mechanistic aspects are discussed in terms of the formation of compact structures developed when CO is adsorbed. The main ideas presented here are focused on the mechanistic aspects that take into account the existence of such structures. The classical kinetic mechanisms of Lagmuir-Hinshelwood and Eley-Rideal are discussed considering the superficial mobility of CO or nucleation-growing of islands formed by oxygen-containing adsorbates.
Carbon monoxide poisoning - Immediate diagnosis and treatment are crucial to avoid complications.
Energy Technology Data Exchange (ETDEWEB)
Rosenthal, L.D. [Case Western Reserve University, Cleveland, OH (United States)
2006-03-15
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.
Selective carbon monoxide oxidation over Ag-based composite oxides
Energy Technology Data Exchange (ETDEWEB)
Guldur, C. [Gazi University, Ankara (Turkey). Chemical Engineering Department; Balikci, F. [Gazi University, Ankara (Turkey). Institute of Science and Technology, Environmental Science Department
2002-02-01
We report our results of the synthesis of 1 : 1 molar ratio of the silver cobalt and silver manganese composite oxide catalysts to remove carbon monoxide from hydrogen-rich fuels by the catalytic oxidation reaction. Catalysts were synthesized by the co-precipitation method. XRD, BET, TGA, catalytic activity and catalyst deactivation studies were used to identify active catalysts. Both CO oxidation and selective CO oxidation were carried out in a microreactor using a reaction gas mixture of 1 vol% CO in air and another gas mixture was prepared by mixing 1 vol% CO, 2 vol% O{sub 2}, 84 vol% H{sub 2}, the balance being He. 15 vol% CO{sub 2} was added to the reactant gas mixture in order to determine the effect of CO{sub 2}, reaction gases were passed through the humidifier to determine the effect of the water vapor on the oxidation reaction. It was demonstrated that metal oxide base was decomposed to the metallic phase and surface areas of the catalysts were decreased when the calcination temperature increased from 200{sup o}C to 500{sup o}C. Ag/Co composite oxide catalyst calcined at 200{sup o}C gave good activity at low temperatures and 90% of CO conversion at 180{sup o}C was obtained for the selective CO oxidation reaction. The addition of the impurities (CO{sub 2} or H{sub 2}O) decreased the activity of catalyst for selective CO oxidation in order to get highly rich hydrogen fuels. (author)
Subclinical carbon monoxide poisoning in our health area
Energy Technology Data Exchange (ETDEWEB)
Arroyo, I.G.; Testa, A.F.; Sangrador, C.O.; Garcia, M.T.A.; Berrocal, J.L.S.; Pastor, N.R.; Martin, J.M.; Garcia, L.S.; Garcia, M.C.F.; Maire-Richard, E.G. [Hospital of Virgen Concha, Zamora (Spain)
2003-08-01
We present an observation study on the relationship 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 {gt}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.
Carbon monoxide measurements at Mace Head, Ireland
Doddridge, Bruce G.; Dickerson, Russell R.; Spain, T. Gerard; Oltmans, Samuel J.; Novelli, Paul C.
1994-01-01
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.
DEFF Research Database (Denmark)
Johansson, Martin; Lytken, Ole; Chorkendorff, Ib
2008-01-01
The sticking probability for H-2 on Ni, Co, Cu, Rh, Ru, Pd, it and Pt metal films supported on graphite has been investigated in a gas mixture consisting of 10 ppm carbon monoxide in hydrogen at a total pressure of 1 bar in the temperature range 40-200 degrees C. Carbon monoxide inhibits the stic......The sticking probability for H-2 on Ni, Co, Cu, Rh, Ru, Pd, it and Pt metal films supported on graphite has been investigated in a gas mixture consisting of 10 ppm carbon monoxide in hydrogen at a total pressure of 1 bar in the temperature range 40-200 degrees C. Carbon monoxide inhibits...... the sticking probability significantly for all the metals, even at 200 degrees C. In the presence of 10 ppm CO, the sticking probability increases in the order It, Pt, Ni, Co, Pd, Rh, Ru, whereas for Cu, it is below the detection limit of the measurement, even in pure H2. The sticking probability for H2...
Li, Ying; Pei, Fei
2014-01-01
Peaches (Prunus persica cv. Yanhong) were fumigated with carbon monoxide (CO) at 0, 0.5, 5, 10, and 20 μmol/L for 2 hours. The result showed that low concentration CO (0.5–10 μmol/L) might delay the decrease of firmness and titrable acid content, restrain the increase of decay incidence, and postpone the variation of soluble solids content, but treating peaches with high concentration CO (20 μmol/L) demonstrated adverse effects. Further research exhibited that exogenous CO could induce the phenylalnine ammonialyase activity, maintain nutrient contents such as Vitamin C, total flavonoid, and polyphenol, and enhance antioxidant activity according to reducing power and 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl radical scavenging activity. Treating peaches with appropriate concentration CO was beneficial to the quality, nutrients, and antioxidant activity of postharvest peaches during storage time. Therefore, CO fumigation might probably become a novel method to preserve postharvest peach and other fruits in the future. PMID:26904651
Four-electron deoxygenative reductive coupling of carbon monoxide at a single metal site
Buss, Joshua A.; Agapie, Theodor
2016-01-01
Carbon dioxide is the ultimate source of the fossil fuels that are both central to modern life and problematic: their use increases atmospheric levels of greenhouse gases, and their availability is geopolitically constrained. Using carbon dioxide as a feedstock to produce synthetic fuels might, in principle, alleviate these concerns. Although many homogeneous and heterogeneous catalysts convert carbon dioxide to carbon monoxide, further deoxygenative coupling of carbon monoxide to generate useful multicarbon products is challenging. Molybdenum and vanadium nitrogenases are capable of converting carbon monoxide into hydrocarbons under mild conditions, using discrete electron and proton sources. Electrocatalytic reduction of carbon monoxide on copper catalysts also uses a combination of electrons and protons, while the industrial Fischer-Tropsch process uses dihydrogen as a combined source of electrons and electrophiles for carbon monoxide coupling at high temperatures and pressures. However, these enzymatic and heterogeneous systems are difficult to probe mechanistically. Molecular catalysts have been studied extensively to investigate the elementary steps by which carbon monoxide is deoxygenated and coupled, but a single metal site that can efficiently induce the required scission of carbon-oxygen bonds and generate carbon-carbon bonds has not yet been documented. Here we describe a molybdenum compound, supported by a terphenyl-diphosphine ligand, that activates and cleaves the strong carbon-oxygen bond of carbon monoxide, enacts carbon-carbon coupling, and spontaneously dissociates the resulting fragment. This complex four-electron transformation is enabled by the terphenyl-diphosphine ligand, which acts as an electron reservoir and exhibits the coordinative flexibility needed to stabilize the different intermediates involved in the overall reaction sequence. We anticipate that these design elements might help in the development of efficient catalysts for
Interannual variability in baseline carbon monoxide (CO) and ozone (O3), defined as mixing ratios under minimal influence of recent and local emissions, was studied for seven rural sites in the Northeast US over 2001–2010. Annual baseline CO exhibited statistically signific...
Ammonia (NH3) and carbon monoxide (CO) are primary pollutants emitted to the Earth's atmosphere from common as well as distinct sources associated with anthropogenic and natural activities. The seasonal and global distributions and correlations of NH3 and CO from the Tropospheric...
Catalytic hydrogenation of carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Wayland, B.B.
1992-12-01
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.
At some level, carboxyhemoglobin (RbCO) due to inhalation of carbon monoxide (CO) reduces maximum exercise duration in normal and ischemic heart patients. At high RbCO levels in normal subjects, brain function is also affected and behavioral performance is impaired. These are fin...
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Weigen Chen
2013-01-01
Full Text Available Pure and M-doped (M = Pt, Fe, and Zn SnO2 nanospheres were successfully synthesized via a simple and facile hydrothermal method and characterized by X-ray powder diffraction, field-emission scanning electron microscopy, and energy dispersive spectroscopy. Chemical gas sensors were fabricated based on the as-synthesized nanostructures, and carbon monoxide sensing properties were systematically measured. Compared to pure, Fe-, and Zn-doped SnO2 nanospheres, the Pt-doped SnO2 nanospheres sensor exhibits higher sensitivity, lower operating temperature, more rapid response and recovery, better stability, and excellent selectivity. In addition, a theoretical study based on the first principles calculation was conducted. All results demonstrate the potential of Pt dopant for improving the gas sensing properties of SnO2-based sensors to carbon monoxide.
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Perez Roberto SGM
2005-06-01
Full Text Available Abstract Background Desflurane and enflurane have been reported to produce substantial amounts of carbon monoxide (CO in desiccated sodalime. Isoflurane is said to produce less CO and sevoflurane and halothane should produce no CO at all. The purpose of this study is to measure the maximum amounts of CO production for all modern volatile anesthetics, with completely dry sodalime. We also tried to establish a relationship between CO production and temperature increase inside the sodalime. Methods A patient model was simulated using a circle anesthesia system connected to an artificial lung. Completely desiccated sodalime (950 grams was used in this system. A low flow anesthesia (500 ml/min was maintained using nitrous oxide with desflurane, enflurane, isoflurane, halothane or sevoflurane. For immediate quantification of CO production a portable gas chromatograph was used. Temperature was measured within the sodalime container. Results Peak concentrations of CO were very high with desflurane and enflurane (14262 and 10654 ppm respectively. It was lower with isoflurane (2512 ppm. We also measured small concentrations of CO for sevoflurane and halothane. No significant temperature increases were detected with high CO productions. Conclusion All modern volatile anesthetics produce CO in desiccated sodalime. Sodalime temperature increase is a poor predictor of CO production.
Jensen, Eric; Bergman, John; Pfister, Leonard; Ueyama, Rei; Kinnison, Doug
2014-01-01
Trajectory calculations with convective influence diagnosed from geostationary-satellite cloud measurements are used to evaluate the relative importance of different Tropical Tropopause Layer (TTL) transport pathways for establishing the distribution of carbon monoxide (CO) at 100 hPa as observed by the Microwave Limb Sounder (MLS) on board the Aura satellite. Carbon monoxide is a useful tracer for investigating TTL transport and convective influence because the CO lifetime is comparable to the time require for slow ascent through the TTL (a couple of months). Offline calculations of TTL radiative heating are used to determine the vertical motion field. The simple trajectory model does a reasonable job of reproducing the MLS CO distributions during Boreal wintertime and summertime. The broad maximum in CO concentration over the Pacific is primarily a result of the strong radiative heating (indicating upward vertical motion) associated with the abundant TTL cirrus in this region. Sensitivity tests indicate that the distinct CO maximum in the Asian monsoon anticyclone is strongly impacted by extreme convective systems with detrainment of polluted air above 360 K potential temperature. The relative importance of different CO source regions will also be discussed.
International Nuclear Information System (INIS)
Kondo-Nakamura, Mihoko; Shintani-Ishida, Kaori; Uemura, Koichi; Yoshida, Ken-ichi
2010-01-01
We examined whether and how pretreatment with carbon monoxide (CO) prevents apoptosis of cardioblastic H9c2 cells in ischemia-reperfusion. Reperfusion (6 h) following brief ischemia (10 min) induced cytochrome c release, activation of caspase-9 and caspase-3, and apoptotic nuclear condensation. Brief CO pretreatment (10 min) or a caspase-9 inhibitor (Z-LEHD-FMK) attenuated these apoptotic changes. Ischemia-reperfusion increased phosphorylation of Akt at Ser472/473/474, and this was enhanced by CO pretreatment. A specific Akt inhibitor (API-2) blunted the anti-apoptotic effects of CO in reperfusion. In normoxic cells, CO enhanced O 2 - generation, which was inhibited by a mitochondrial complex III inhibitor (antimycin A) but not by a NADH oxidase inhibitor (apocynin). The CO-enhanced Akt phosphorylation was suppressed by an O 2 - scavenger (Tiron), catalase or a superoxide dismutase (SOD) inhibitor (DETC). These results suggest that CO pretreatment induces mitochondrial generation of O 2 - , which is then converted by SOD to H 2 O 2 , and subsequent Akt activation by H 2 O 2 attenuates apoptosis in ischemia-reperfusion.
Carbon monoxide: from toxin to endogenous modulator of cardiovascular functions
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R.A. Johnson
1999-01-01
Full Text Available Carbon monoxide (CO is a pollutant commonly recognized for its toxicological attributes, including CNS and cardiovascular effects. But CO is also formed endogenously in mammalian tissues. Endogenously formed CO normally arises from heme degradation in a reaction catalyzed by heme oxygenase. While inhibitors of endogenous CO production can raise arterial pressure, heme loading can enhance CO production and lead to vasodepression. Both central and peripheral tissues possess heme oxygenases and generate CO from heme, but the inability of heme substrate to cross the blood brain barrier suggests the CNS heme-heme oxygenase-CO system may be independent of the periphery. In the CNS, CO apparently acts in the nucleus tractus solitarii (NTS promoting changes in glutamatergic neurotransmission and lowering blood pressure. At the periphery, the heme-heme oxygenase-CO system can affect cardiovascular functions in a two-fold manner; specifically: 1 heme-derived CO generated within vascular smooth muscle (VSM can promote vasodilation, but 2 its actions on the endothelium apparently can promote vasoconstriction. Thus, it seems reasonable that the CNS-, VSM- and endothelial-dependent actions of the heme-heme oxygenase-CO system may all affect cardiac output and vascular resistance, and subsequently blood pressure.
Carbon monoxide and coronary heart disease
Energy Technology Data Exchange (ETDEWEB)
Scheidemandel, V
1974-01-01
Studies on the relationship between increased carboxyhemoglobin levels in the blood and coronary heart disease in smokers and city dwellers are reviewed. The evidence of myocardial infarction is significantly higher in smokers than in nonsmokers which is due, apart from nicotine which promotes coronary arteriosclerosis, to inhaled carbon monoxide which leads to increased carboxyhemoglobin levels and most likely plays a role in the risk of arteriosclerosis and the coronary heart disease. Apart from combining with hemoglobin, CO increases the circulation rate and the coronary blood flow, and reduces the coronary arteriovenous oxygen difference, which is indicative of a reduced rate of oxygen extraction by the myocardium against an increased myocardial oxygen demand. The reduction of the oxygen extraction correlates with the increased COHb level. Inhaled CO lowers the threshold of angina pectoris due to the reduced myocardial oxygen tension. Also, considerable reduction of the oxygen diffusion from the capillaries toward the mitochondria due to the combination of CO with myoglobin is observed. Chronically increased CO levels in the blood and tissues not only accelerate the development of arteriosclerosis, but also induce a process directly injurious to the myocardial metabolism. (Air Pollut. Abstr.)
The immunomodulatory role of carbon monoxide during transplantation
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Amano Mariane
2013-01-01
Full Text Available Abstract 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.
Multi-objective optimisation in carbon monoxide gas management at TRONOX KXN Sands
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Stadler, Johan
2014-08-01
Full Text Available Carbon monoxide (CO is a by-product of the ilmenite smelting process from which titania slag and pig iron are produced. Prior to this project, the CO at Tronox KZN Sands in South Africa was burnt to get rid of it, producing carbon dioxide (CO2. At this plant, unprocessed materials are pre-heated using methane gas from an external supplier. The price of methane gas has increased significantly; and so this research considers the possibility of recycling CO gas and using it as an energy source to reduce methane gas demand. It is not possible to eliminate the methane gas consumption completely due to the energy demand fluctuation, and sub-plants have been assigned either CO gas or methane gas over time. Switching the gas supply between CO and methane gas involves production downtime to purge supply lines. Minimising the loss of production time while maximising the use of CO arose as a multi-objective optimisation problem (MOP with seven decision variables, and computer simulation was used to evaluate scenarios. We applied computer simulation and the multi-objective optimisation cross-entropy method (MOO CEM to find good solutions while evaluating the minimum number of scenarios. The proposals in this paper, which are in the process of being implemented, could save the company operational expenditure while reducing the carbon footprint of the smelter.
Copolymerization of carbon monoxide and styrene catalyzed by resin-supported palladium polymer
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2007-02-01
Full Text Available Polyketone was prepared by the copolymerization of carbon monoxide (CO and styrene (ST catalyzed by o-phenylenediamine resin-supported palladium acetate. Effects of each catalytic system component such as 2,2’-bipyridine, 1,4-quinone and p-toluene-sulphonate on the copolymerization were investigated. The resin-supported catalyst and the copolymerization product were characterized by infrared spectroscopy (IR, differential scanning calorimetry (DSC, thermogravimetry (TG, X-ray photoelectron spectroscopy (XPS, Scanning Electron Microscopy (SEM. Results indicated that the resin-supported catalyst has excellent catalytic property. Furthermore, partial catalytic activity was maintained after the catalyst was used for five times.
Borsdorff, Tobias; De Brugh, Joost Aan; Hu, Haili; Nédélec, Philippe; Aben, Ilse; Landgraf, Jochen
2017-01-01
We discuss the retrieval of carbon monoxide (CO) vertical column densities from clear-sky and cloud contaminated 2311-2338 nm reflectance spectra measured by the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) from January 2003 until the end of the mission in April
Role of carboxydobacteria in consumption of atmospheric carbon monoxide by soil
Energy Technology Data Exchange (ETDEWEB)
Conrad, R. (Max-Planck-Institut fuer Chemie, Mainz, Germany); Meyer, O.; Seiler, W.
1981-08-01
The carbon monoxide consumption rates of the carboxydobacteria Pseudomonas (Seliberia) carboxydohydrogena, P. carboxydovorans, and P. carboxydoflava were measured at high (50%) and low (0.5 ..mu..l liter/sup -1/) mixing ratios of CO in air. CO was only consumed when the bacteria had been grown under CO-autotrophic conditions. At low cell densities the CO comsumption rates measured at low CO mixing ratios were similar in cell suspensions and in mixtures of bacteria in soil. CO consumption observed in natural soil (loess, eolian sand, chernozem) as well as in suspensions or soil mixtures of carboxydobacteria showed Michaelis-Menten kinetics. Considering the difference of the K/sub m/, values and the observed V/sub max/ values, carboxydobacteria cannot contribute significantly to the consumption of atmospheric CO.
Study on the influence of carbon monoxide to the surface oxide layer of uranium metal
International Nuclear Information System (INIS)
Wang Xiaolin; Duan Rongliang; Fu Yibei; Xie Renshou; Zuo Changming; Zhao Chunpei; Chen Hong
1997-01-01
The influence of carbon monoxide to the surface oxide layer of uranium metal has been studied by X-ray photoelectron spectroscopy (XPS) and gas chromatography (GC). Carbon monoxide adsorption on the oxide layer resulted in U4f peak shifting to the lower binding energy. The content of oxygen in the oxide is decreased and the atomic ratio (O/U) is decreased by 7.2%. The amount of carbon dioxide in the atmosphere after the surface reaction is increased by 11.0%. The investigation indicates that the surface layer can prevent the further oxidation uranium metal in the atmosphere of carbon monoxide
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Z. Wang
2012-05-01
Full Text Available We present a 60-year record of the stable isotopes of atmospheric carbon monoxide (CO from firn air samples collected under the framework of the North Greenland Eemian Ice Drilling (NEEM project. CO concentration, δ13C, and δ18O of CO were measured by gas chromatography/isotope ratio mass spectrometry (gc-IRMS from trapped gases in the firn. We applied LGGE-GIPSA firn air models (Witrant et al., 2011 to correlate gas age with firn air depth and then reconstructed the trend of atmospheric CO and its stable isotopic composition at high northern latitudes since 1950. The most probable firn air model scenarios show that δ13C decreased slightly from −25.8‰ in 1950 to −26.4‰ in 2000, then decreased more significantly to −27.2‰ in 2008. δ18O decreased more regularly from 9.8‰ in 1950 to 7.1‰ in 2008. Those same scenarios show CO concentration increased gradually from 1950 and peaked in the late 1970s, followed by a gradual decrease to present day values (Petrenko et al., 2012. Results from an isotope mass balance model indicate that a slight increase, followed by a large reduction, in CO derived from fossil fuel combustion has occurred since 1950. The reduction of CO emission from fossil fuel combustion after the mid-1970s is the most plausible mechanism for the drop of CO concentration during this time. Fossil fuel CO emissions decreased as a result of the implementation of catalytic converters and the relative growth of diesel engines, in spite of the global vehicle fleet size having grown several fold over the same time period.
Almeida, Ana S; Sonnewald, Ursula; Alves, Paula M; Vieira, Helena L A
2016-08-01
The process of cell differentiation goes hand-in-hand with metabolic adaptations, which are needed to provide energy and new metabolites. Carbon monoxide (CO) is an endogenous cytoprotective molecule able to inhibit cell death and improve mitochondrial metabolism. Neuronal differentiation processes were studied using the NT2 cell line, which is derived from human testicular embryonic teratocarcinoma and differentiates into post-mitotic neurons upon retinoic acid treatment. CO-releasing molecule A1 (CORM-A1) was used do deliver CO into cell culture. CO treatment improved NT2 neuronal differentiation and yield, since there were more neurons and the total cell number increased following the differentiation process. CO supplementation enhanced the mitochondrial population in post-mitotic neurons derived from NT2 cells, as indicated by an increase in mitochondrial DNA. CO treatment during neuronal differentiation increased the extent of the classical metabolic change that occurs during neuronal differentiation, from glycolytic to more oxidative metabolism, by decreasing the ratio of lactate production and glucose consumption. The expression of pyruvate and lactate dehydrogenases was higher, indicating an augmented oxidative metabolism. Moreover, these findings were corroborated by an increased percentage of (13) C incorporation from [U-(13) C]glucose into the tricarboxylic acid cycle metabolites malate and citrate, and also glutamate and aspartate in CO-treated cells. Finally, under low levels of oxygen (5%), which enhances glycolytic metabolism, some of the enhancing effects of CO on mitochondria were not observed. In conclusion, our data show that CO improves neuronal and mitochondrial yield by stimulation of tricarboxylic acid cycle activity, and thus oxidative metabolism of NT2 cells during the process of neuronal differentiation. The process of cell differentiation is coupled with metabolic adaptations. Carbon monoxide (CO) is an endogenous cytoprotective
Kinetics of carbon monoxide oxidation over modified supported CuO catalysts
Energy Technology Data Exchange (ETDEWEB)
Loc, Luu Cam; Tri, Nguyen; Cuong, Hoang Tien; Thoang, Ho Si [Vietnam Academy of Science and Technology (VAST), Ho Chi Minh City (Viet Nam). Inst. of Chemical Technology; Agafonov, Yu.A.; Gaidai, N.A.; Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry
2013-11-01
The following supported on {gamma}-Al{sub 2}O{sub 3} catalysts: 10(wt.)%CuO (CuAl), 10%CuO+10%Cr{sub 2}O{sub 3} (CuCrAl) and 10%CuO+20%CeO{sub 2} (CuCeAl) were under the investigation. Physico-chemical characteristics of the catalysts were determined by the methods of BET, X-ray Diffraction (XRD), and Temperature-Programmed Reduction (TPR). A strong interaction of copper with support in CuAl resulted in the formation of low active copper aluminates. The bi-oxide CuCrAl was more active than CuAl owing to the formation of high catalytically active spinel CuCr{sub 2}O{sub 4}. The fact of very high activity of the sample CuCeAl can be explained by the presence of the catalytically active form of CuO-CeO{sub 2}-Al{sub 2}O{sub 3}. The kinetics of CO total oxidation was studied in a gradientless flow-circulating system at the temperature range between 200 C and 270 C. The values of initial partial pressures of carbon monoxide (P{sup o}{sub CO}), oxygen (P{sup o}{sub O2}), and specially added carbon dioxide (P{sup o}{sub CO{sub 2}}) were varied in ranges (hPa): 10 / 45; 33 / 100, and 0 / 30, respectively. (orig.)
Experimental and clinical study of chronic poisoning by carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Thiele, H.; Gohlke, R.; Rothe, R.
1973-01-01
Animal and clinical tests on carbon monoxide-exposed subjects are described in an attempt to demonstrate the specific chronic action of CO. Rabbits exposed to 802 ppM and 284 ppM CO for 103 and 112 days, respectively, for 5 days a week showed carboxyhemoglobin values in the respective ranges of 2.5 to 11.9% and 2.5 to 8.3%. The macroscopic findings and gain in weight were normal, except for an increase by 20% and 14% in the weight of the liver. Dose-dependent increases in the hemoglobin and hematocrit levels, significant increases in the pyruvate level of the first group, and significant reductions of the cholinesterase, inorganic phosphate levels, hepatic lipase, phosphate, phosphatase, and cytochrome-C oxidase were observed. An increased cholinesterase level was found in brain homogenates. Inhibition of the glucose-6-phosphatase was observed. There is a specific damage due to CO in addition to merely the hypoxic effect. Clinical tests in humans with and without acute, subacute, or chronic exposure to CO revealed that acute and subacute poisoning have no additional pathogenic effect in chronic exposure, i.e., indicate the existence of primary chronic poisoning with CO.
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Martin Nnoli
2014-11-01
Full Text Available Background: This toxicological investigation involves a report on the death of four occupants of a sport utility vehicle on one of the major busy Federal roads of Nigeria where they were held for up to three hours in a traffic jam while the car was steaming. Methods: Autopsy was executed using the standard procedure and toxicological analysis was done using simple spectrophotometric method to establish the level of carboxyhaemoglobin (HbCO in peripheral blood in the four occupants. Results: The autopsy report indicated generalized cyanosis, sub-conjuctival hemorrhages, marked laryngo-trachea edema with severe hyperemia with frothy fluid discharges characteristic of carbon monoxide poisoning. Toxicological report of the level of HbCO in part per million (ppm in the peripheral blood of the four occupants was A= 650 ppm; B= 500 ppm; C= 480 ppm, and D= 495 ppm against the maximum permissible level of 50 ppm. Conclusion: The sudden death of the four occupants was due to excessive inhalation of the carbon monoxide gas from the exhaust fumes leaking into the cabin of the car. The poor road network, numerous potholes, and traffic jam in most of roads in Nigeria could have exacerbated a leaky exhaust of the smoky second hand SUV car leading to the acute carbon monoxide poisoning.
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A. T. J. de Laat
2012-09-01
Full Text Available This paper presents a validation study of SCanning Imaging Absorption SpectroMeter for Atmospheric CartograpHY (SCIAMACHY carbon monoxide (CO total column measurements from the Iterative Maximum Likelihood Method (IMLM algorithm using vertically integrated profile aircraft measurements obtained within the MOZAIC project for the six year time period of 2003–2008.
Overall we find a good agreement between SCIAMACHY and airborne measurements for both mean values – also on a year-to-year basis – as well as seasonal variations. Several locations show large biases that are attributed to local effects like orography and proximity of large emission sources. Differences were detected for individual years: 2003, 2004 and 2006 have larger biases than 2005, 2007 and 2008, which appear to be related to SCIAMACHY instrumental issues but require more research. Results from this study are consistent with, and complementary to, findings from a previous validation study using ground-based measurements (de Laat et al., 2010b. According to this study, the SCIAMACHY data, if individual measurements are of sufficient quality – good signal-to-noise, can be used to determine the spatial distribution and seasonal cycles of CO total columns over clean areas. Biases found over areas with strong emissions (Africa, China could be explained by low sensitivity of the instrument in the boundary layer and users are recommended to avoid using the SCIAMACHY data while trying to quantify CO burden and/or retrieve CO emissions in such areas.
Use of carbon monoxide and hydrogen by a bacteria–animal symbiosis from seagrass sediments
Holler, Thomas; Lavik, Gaute; Harder, Jens; Lott, Christian; Littmann, Sten; Kuypers, Marcel M. M.; Dubilier, Nicole
2015-01-01
Summary The gutless marine worm O lavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing carbon dioxide (CO 2) into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O . algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H 2) might also be used as energy sources. We provide direct evidence that the O . algarvensis symbiosis consumes CO and H 2. Single cell imaging using nanoscale secondary ion mass spectrometry revealed that one of the symbionts, the γ3‐symbiont, uses the energy from CO oxidation to fix CO 2. Pore water analysis revealed considerable in‐situ concentrations of CO and H 2 in the O . algarvensis environment, Mediterranean seagrass sediments. Pore water H 2 concentrations (89–2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36‐fold higher than previously known from shallow‐water marine sediments. Pore water CO concentrations (17–51 nM) were twice as high as in the overlying seawater (no literature data from other shallow‐water sediments are available for comparison). Ex‐situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments. PMID:26013766
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Ronaldo Laranjeira
2000-07-01
Full Text Available CONTEXT: Exposure to environmental tobacco smoke is a health risk that is of concern to patrons and of particular concern to employees of restaurants and bars. OBJECTIVE: To assess environmental tobacco smoke exposure (using expired carbon monoxide levels in non-smoking waiters before and after a normal day's shift and to compare pre-exposure levels with non-smoking medical students. DESIGN: An observational study. SETTING: Restaurants with more than 50 tables or 100 places in São Paulo. SUBJECTS: 100 non-smoking restaurant waiters and 100 non-smoking medical students in São Paulo, Brazil. MAIN MEASUREMENTS: Levels of expired carbon monoxide, measured with a Smokerlyser (Bedfont EC 50 Scientific, before and after a normal day's work. RESULTS: Waiters' pre-exposure expired carbon monoxide levels were similar to those of medical students, but after a mean of 9 hours exposure in the workplace, median levels more than doubled (2.0 ppm vs. 5.0 ppm, P <0.001. Post-exposure carbon monoxide levels were correlated with the number of tables available for smokers (Kendall's tau = 0.2, P <0.0001. CONCLUSIONS: Exposure to environmental tobacco smoke is the most likely explanation for the increase in carbon monoxide levels among these non-smoking waiters. These findings can be used to inform the ongoing public health debate on passive smoking.
1H MR spectroscopy of gray and white matter in carbon monoxide poisoning
DEFF Research Database (Denmark)
Kondziella, D.; Danielsen, E.R.; Hansen, K.
2009-01-01
Carbon monoxide (CO) intoxication leads to acute and chronic neurological deficits, but little is known about the specific noxious mechanisms. (1)H magnetic resonance spectroscopy (MRS) may allow insight into the pathophysiology of CO poisoning by monitoring neurochemical disturbances, yet only......, magnetic resonance imaging (MRI) and neuropsychological testing. Five patients suffered from acute high-dose CO intoxication and were in coma for 1-6 days. In these patients, MRI revealed hyperintensities of the white matter and globus pallidus and also showed increased choline (Cho) and decreased N...
Metin Uysalol; Ezgi Paslı Uysalol; Gamze Varol Saraçoğlu; Semra Kayaoğlu
2011-01-01
Objective: The aim of the study is to analyze the general aspects of cases with carbon monoxide intoxication in order to improve the approach to future patients. Material and Methods: The hospital records of 84 children (mean age 4.71±2.64 years; 48 male, 36 female) who had been admitted to Paediatric Emergency Department for carbon monoxide intoxication between October 2007 and February 2009, were retrospectively evaluated in a descriptive analysis.Results: The source of carbon monoxide into...
Poisoning by carbon monoxide in Morocco from 1991 to 2008.
Aghandous, Rachida; Chaoui, Hanane; Rhalem, Naima; Semllali, Ilham; Badri, Mohamed; Soulaymani, Abdelmajid; Ouammi, Lahcen; Soulaymani-Bencheikh, Rachida
2012-04-01
To describe the characteristics relating to the provenance of statements, patients and to evaluate the spatiotemporal evolution of carbon monoxide poisoning reported to Poison Control Center and Pharmacovigilance of Morocco (CAPM). This is a retrospective study over a period of 18 years from 1991 to 2008, for all cases of poisoning by carbon monoxide reported to CAPM. The epidemiological study focused on 12 976 cases of carbon monoxide poisoning reported to CAPM between 1991 and 2008. The average age of patients was 25.5 +/- 15.6 years, sex ratio was 0.5. The poisoning occurred by accident in 98.7% of cases, especially at home (96.7%) and in cold months. The urban population was the most affected (89.0%). The region of Meknes Tafilalt was the most concerned with 16.6% of cases. The symptomatology was characterized by the predominance of gastrointestinal tract diseases (37.1%). Deaths have reached a percentage of 0.9%. These qualitative and quantitative information is useful to highlight warnings and plan a strategy against carbon monoxide poisoning in Morocco.
Variability in hyperbaric oxygen treatment for acute carbon monoxide poisoning.
Byrne, Brendan T; Lu, Jenny J; Valento, Matthew; Bryant, Sean M
2012-01-01
In patients with acute carbon monoxide (CO) poisoning, we have noted wide clinical variability in both criteria for hyperbaric oxygen (HBO2) treatment as well as HBO2 treatment regimens. Our aim was to survey Midwest hyperbaric centers for insight into specific criteria and protocols for treating acute CO toxicity with HBO2. Hyperbaric centers were identified from the published list of the Undersea and Hyperbaric Medical Society. Ninety-three centers from nine Midwestern states were contacted via telephone. A standard script was used to minimize surveyor bias. Thirty centers that treat CO poisonings were identified. One did not participate in the study. Nineteen reported a specific level of carboxyhemoglobin (COHb) that served as an independent indication for initiation of HBO2 treatment. Four centers used the COHb level as the exclusive indication for HBO2 treatment. Ten centers relied solely on reported symptoms, while the remaining centers used a combination of symptoms plus COHb levels. There were 19 separate treatment protocols. No uniform practice for either the initiation or implementation of HBO2 therapy for CO poisoning exists among U.S. Midwest hyperbaric centers responding to a survey. We see opportunity for specific targeted educational programs as well as further study.
Bauduin, Sophie; Clarisse, Lieven; Theunissen, Michael; George, Maya; Hurtmans, Daniel; Clerbaux, Cathy; Coheur, Pierre-François
2017-03-01
Separating concentrations of carbon monoxide (CO) in the boundary layer from the rest of the atmosphere with nadir satellite measurements is of particular importance to differentiate emission from transport. Although thermal infrared (TIR) satellite sounders are considered to have limited sensitivity to the composition of the near-surface atmosphere, previous studies show that they can provide information on CO close to the ground in case of high thermal contrast. In this work we investigate the capability of IASI (Infrared Atmospheric Sounding Interferometer) to retrieve near-surface CO concentrations, and we quantitatively assess the influence of thermal contrast on such retrievals. We present a 3-part analysis, which relies on both theoretical forward simulations and retrievals on real data, performed for a large range of negative and positive thermal contrast situations. First, we derive theoretically the IASI detection threshold of CO enhancement in the boundary layer, and we assess its dependence on thermal contrast. Then, using the optimal estimation formalism, we quantify the role of thermal contrast on the error budget and information content of near-surface CO retrievals. We demonstrate that, contrary to what is usually accepted, large negative thermal contrast values (ground cooler than air) lead to a better decorrelation between CO concentrations in the low and the high troposphere than large positive thermal contrast (ground warmer than the air). In the last part of the paper we use Mexico City and Barrow as test cases to contrast our theoretical predictions with real retrievals, and to assess the accuracy of IASI surface CO retrievals through comparisons to ground-based in-situ measurements.
Ando, Takahiro; Mori, Atsushi; Ito, Rie; Nishiwaki, Kimitoshi
2017-12-01
We investigated whether calcium chloride (CaCl 2 ), a supplementary additive in carbon dioxide (CO 2 ) absorbents, could affect carbon monoxide (CO) production caused by desflurane degradation, using a Japanese alkali-free CO 2 absorbent Yabashi Lime ® -f (YL-f), its CaCl 2 -free and 1% CaCl 2 -added derivatives, and other commercially available alkali-free absorbents with or without CaCl 2 . The reaction between 1 L of desflurane gas (3-10%) and 20 g of desiccated specimen was performed in an artificial closed-circuit anesthesia system for 3 min at 20 or 40 °C. The CO concentration was measured using a gas chromatograph equipped with a semiconductor sensor detector. The systems were validated by detecting dose-dependent CO production with an alkali hydroxide-containing CO 2 absorbent, Sodasorb ® . Compared with YL-f, the CaCl 2 -free derivative caused the production of significantly more CO, while the 1% CaCl 2 -added derivative caused the production of a comparable amount of CO. These phenomena were confirmed using commercially available absorbents AMSORB ® PLUS, an alkali-free absorbent with CaCl 2 , and LoFloSorb™, an alkali-free absorbent without CaCl 2 . These results suggest that CaCl 2 plays an important role in preventing CO generation caused by desflurane degradation with alkali hydroxide-free CO 2 absorbents like YL-f.
International Nuclear Information System (INIS)
Turner, G; Richardson, A J; Maxwell, N S; Pringle, J S M; Ingham, S A; Fudge, B W
2014-01-01
The optimized carbon monoxide (CO) rebreathing method (oCOR-method) is routinely used to measure total haemoglobin mass (tHbmass). The tHbmass measure is subject to a test-retest typical error of ∼2%, mostly from the precision of carboxyhaemoglobin (HbCO) measurement. We hypothesized that tHbmass would be robust to differences in the bolus of CO administered during the oCOR-method. Twelve participants (ten males and two females; age 27 ± 6 yr, height 177 ± 11 cm and mass 73.9 ± 12.1 kg) completed the oCOR-method on four occasions. Different bolus of CO were administered (LOW: 0.6 ml kg −1 ; MED 1 : 1.0 ml kg −1 and HIGH: 1.4 ml kg −1 ); to determine the reliability of MED 1 , a second trial was conducted (MED 2 ). tHbmass was found to be significantly less from the HIGH CO bolus (776 ± 148 g) when compared to the LOW CO (791 ± 149 g) or MED 1 CO (788 ± 149 g) trials. MED 2 CO was 785 ± 150 g. The measurement of tHbmass is repeatable to within 0.8%, but a small and notable difference was seen when using a HIGH CO bolus (1.4 to 1.9% less), potentially due to differences in CO uptake kinetics. Previously, an improved precision of the oCOR-method was thought to require a higher bolus of CO (i.e. larger ▵%HbCO), as commercial hemoximeters only estimate %HbCO levels to a single decimal place (usually ± 0.1%). With the new hemoximeter used in this study, a bolus of 1.0 ml kg −1 allows adequate precision with acceptable safety. (note)
Electroreduction of carbon monoxide to liquid fuel on oxide-derived nanocrystalline copper
Li, Christina W.; Ciston, Jim; Kanan, Matthew W.
2014-04-01
The electrochemical conversion of CO2 and H2O into liquid fuel is ideal for high-density renewable energy storage and could provide an incentive for CO2 capture. However, efficient electrocatalysts for reducing CO2 and its derivatives into a desirable fuel are not available at present. Although many catalysts can reduce CO2 to carbon monoxide (CO), liquid fuel synthesis requires that CO is reduced further, using H2O as a H+ source. Copper (Cu) is the only known material with an appreciable CO electroreduction activity, but in bulk form its efficiency and selectivity for liquid fuel are far too low for practical use. In particular, H2O reduction to H2 outcompetes CO reduction on Cu electrodes unless extreme overpotentials are applied, at which point gaseous hydrocarbons are the major CO reduction products. Here we show that nanocrystalline Cu prepared from Cu2O (`oxide-derived Cu') produces multi-carbon oxygenates (ethanol, acetate and n-propanol) with up to 57% Faraday efficiency at modest potentials (-0.25 volts to -0.5 volts versus the reversible hydrogen electrode) in CO-saturated alkaline H2O. By comparison, when prepared by traditional vapour condensation, Cu nanoparticles with an average crystallite size similar to that of oxide-derived copper produce nearly exclusive H2 (96% Faraday efficiency) under identical conditions. Our results demonstrate the ability to change the intrinsic catalytic properties of Cu for this notoriously difficult reaction by growing interconnected nanocrystallites from the constrained environment of an oxide lattice. The selectivity for oxygenates, with ethanol as the major product, demonstrates the feasibility of a two-step conversion of CO2 to liquid fuel that could be powered by renewable electricity.
Far-ultraviolet fluorescence of carbon monoxide in the red giant Arcturus
International Nuclear Information System (INIS)
Ayres, T.R.; Moos, H.W.; Linsky, J.L.
1981-01-01
We present evidence that many of the weak features observed with the International Ultraviolet Explorer (IUE) in the far-ultraviolet (1150--2000 A) spectrum of the archetype red giant Arcturus (K2 III) are A--X fourth positive bands of carbon monoxide excited by chromospheric emissions of O I, C I, and H I. The appearance of fluorescent CO bands near the wavelengths of commonly used indicators of high-temperature (T>2 x 10 4 K) plasma, such as C II lambda1335 and C IV lambda1548, introduces a serious ambiguity in diagnosing the presence of hot material in the outer atmospheres of the cool giants by means of low-dispersion IUE spectra
Energy Technology Data Exchange (ETDEWEB)
Vranckx, S. [Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB), CP 160/09, B-1050 Brussels (Belgium); Laboratoire de Chimie Physique (UMR 8000), Université Paris-Sud, Orsay 91405 (France); Loreau, J.; Vaeck, N. [Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles (ULB), CP 160/09, B-1050 Brussels (Belgium); Meier, C. [Laboratoire Collisions Agrégats Réactivité, UMR 5589, IRSAMC, Université Toulouse III Paul Sabatier, Bât. 3R1b4, Toulouse (France); Desouter-Lecomte, M., E-mail: michele.desouter-lecomte@u-psud.fr [Laboratoire de Chimie Physique (UMR 8000), Univ. Paris Sud, Université Paris-Saclay, Orsay 91405 (France); Département de Chimie, B6c Université de Liège, Sart Tilman, 4000 Liège (Belgium)
2015-10-28
The photodissociation and laser assisted dissociation of the carbon monoxide dication X{sup 3}Π CO{sup 2+} into the {sup 3}Σ{sup −} states are investigated. Ab initio electronic structure calculations of the adiabatic potential energy curves, radial nonadiabatic couplings, and dipole moments for the X {sup 3}Π state are performed for 13 excited {sup 3}Σ{sup −} states of CO{sup 2+}. The photodissociation cross section, calculated by time-dependent methods, shows that the C{sup +} + O{sup +} channels dominate the process in the studied energy range. The carbon monoxide dication CO{sup 2+} is an interesting candidate for control because it can be produced in a single, long lived, v = 0 vibrational state due to the instability of all the other excited vibrational states of the ground {sup 3}Π electronic state. In a spectral range of about 25 eV, perpendicular transition dipoles couple this {sup 3}Π state to a manifold of {sup 3}Σ{sup −} excited states leading to numerous C{sup +} + O{sup +} channels and a single C{sup 2+} + O channel. This unique channel is used as target for control calculations using local control theory. We illustrate the efficiency of this method in order to find a tailored electric field driving the photodissociation in a manifold of strongly interacting electronic states. The selected local pulses are then concatenated in a sequence inspired by the “laser distillation” strategy. Finally, the local pulse is compared with optimal control theory.
Rich, Alisa L; Patel, Jay T
2015-01-01
Carbon disulfide (CS2) has been historically associated with the production of rayon, cellophane, and carbon tetrachloride. This study identifies multiple mechanisms by which CS2 contributes to the formation of CO2 in the atmosphere. CS2 and other associated sulfide compounds were found by this study to be present in emissions from unconventional shale gas extraction and processing (E&P) operations. The breakdown products of CS2; carbonyl sulfide (COS), carbon monoxide (CO), and sulfur dioxide (SO2) are indirect greenhouse gases (GHGs) that contribute to CO2 levels in the atmosphere. The heat-trapping nature of CO2 has been found to increase the surface temperature, resulting in regional and global climate change. The purpose of this study is to identify five mechanisms by which CS2 and the breakdown products of CS2 contribute to atmospheric concentrations of CO2. The five mechanisms of CO2 formation are as follows: Chemical Interaction of CS2 and hydrogen sulfide (H2S) present in natural gas at high temperatures, resulting in CO2 formation;Combustion of CS2 in the presence of oxygen producing SO2 and CO2;Photolysis of CS2 leading to the formation of COS, CO, and SO2, which are indirect contributors to CO2 formation;One-step hydrolysis of CS2, producing reactive intermediates and ultimately forming H2S and CO2;Two-step hydrolysis of CS2 forming the reactive COS intermediate that reacts with an additional water molecule, ultimately forming H2S and CO2. CS2 and COS additionally are implicated in the formation of SO2 in the stratosphere and/or troposphere. SO2 is an indirect contributor to CO2 formation and is implicated in global climate change.
Protect Yourself from Carbon Monoxide Poisoning
Centers for Disease Control (CDC) Podcasts
2007-11-20
Learn about carbon monoxide - a colorless, odorless gas - and how to protect yourself and your family. Created: 11/20/2007 by CDC National Center for Environmental Health. Date Released: 12/4/2007.
Energy Technology Data Exchange (ETDEWEB)
Kondo-Nakamura, Mihoko [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shintani-Ishida, Kaori, E-mail: kaori@m.u-tokyo.ac.jp [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Uemura, Koichi; Yoshida, Ken-ichi [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
2010-03-12
We examined whether and how pretreatment with carbon monoxide (CO) prevents apoptosis of cardioblastic H9c2 cells in ischemia-reperfusion. Reperfusion (6 h) following brief ischemia (10 min) induced cytochrome c release, activation of caspase-9 and caspase-3, and apoptotic nuclear condensation. Brief CO pretreatment (10 min) or a caspase-9 inhibitor (Z-LEHD-FMK) attenuated these apoptotic changes. Ischemia-reperfusion increased phosphorylation of Akt at Ser472/473/474, and this was enhanced by CO pretreatment. A specific Akt inhibitor (API-2) blunted the anti-apoptotic effects of CO in reperfusion. In normoxic cells, CO enhanced O{sub 2}{sup -} generation, which was inhibited by a mitochondrial complex III inhibitor (antimycin A) but not by a NADH oxidase inhibitor (apocynin). The CO-enhanced Akt phosphorylation was suppressed by an O{sub 2}{sup -} scavenger (Tiron), catalase or a superoxide dismutase (SOD) inhibitor (DETC). These results suggest that CO pretreatment induces mitochondrial generation of O{sub 2}{sup -}, which is then converted by SOD to H{sub 2}O{sub 2}, and subsequent Akt activation by H{sub 2}O{sub 2} attenuates apoptosis in ischemia-reperfusion.
1993-05-01
It has been suggested that passenger protective breathing equipment protect aircraft passengers from smoke for 5 min during an evacuation phase and for 35 min during an in-flight-plus-evacuation phase. Carbon monoxide (CO) is one of the most abundant...
Conversion of carbon monoxide intensities tomolecular hydrogen abundances
International Nuclear Information System (INIS)
Kutner, M.L.; Leung, C.M.
1985-01-01
We present results of theoretical models (static spherical clouds with a microturbulent velocity field) to study the conversion of carbon monoxide (CO) line parameters into molecular hydrogen (H 2 ) column densities, N2. The three potential H 2 tracers that we investigate are the integrated 12 CO and 13 CO intensities, I 12 and I 13 , and the 13 CO LTE column density, N( 13 . We find that I 12 may be a reasonable tracer of N2 under conditions appropriate to the envelopes of giant molecular clouds and for studies involving cloud ensembles of different cloud sizes and velocity dispersions. However, it saturates under higher density conditions. It is important that empirical conversion factors be set using the types of objects to which they will be applied. For this reason, our analysis suggests that the conversion factor N2/I 12 for giant molecular clouds in the molecular ring of our galaxy may be a factor of 2 lower than the average used by many observers. This lower value is supported by some recent empirical determinations. The quantity I 13 is a good tracer of N2 over a wide range of densities but it is more sensitive to the actual 13 CO abundance. The quantity N( 13 is similar to I 13 as a good tracer of N2 except at low densities and temperatures. The ratio I 12 /I 13 may be used to delineate temperature and column density effects. Finally, we find a strong temperature dependence in the various conversion factors, with N2/I 12 scaling with gas temperature (T/sub k/ approximately as (T/sub k/)/sup -1.3/
Investigation of Carbon Monoxide Adsorption on Cationic Gold- Palladium Clusters
Chen, Yang-Mei; Kuang, Xiao-Yu; Sheng, Xiao-Wei; Wang, Huai-Qian; Shao, Peng; Zhong, Min-Ming
2013-11-01
Density functional calculations have been performed for the carbon monoxide molecule adsorption on AunPd+m(n+m ≤ 6) clusters. In the process of CO adsorption, small Au clusters and Pd clusters tend to be an Au atom and three Pd atoms adsorption, respectively. For the mixed Au-Pd clusters, an Au atom, a Pd atom, two atoms consisted of an Au atom and a Pd atom, two Pd atoms, and three Pd atoms adsorption structures are displayed. The highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gaps and natural bond orbital charge population are calculated. Moreover, CO adsorption energy, CO stretching frequency, and CO bond length (upon adsorption) are also analysed in detail. The results predict that the adsorption strength of Au clusters with CO and the C-O vibration strength is enhanced and reduced after doping of Pd in the AunPdmCO+ complexes, respectively
Photoinduced transport in an H64Q neuroglobin antidote for carbon monoxide poisoning
Rydzewski, J.; Nowak, W.
2018-03-01
Carbon monoxide (CO) is a leading cause of poisoning deaths worldwide, without available antidotal therapy. Recently, a potential treatment for CO poisoning was introduced, based on binding of CO by neuroglobin (Ngb) with a mutated distal histidine (H64Q). Here, we present an atomistic mechanism of CO trapping by H64Q Ngb revealed by nonadiabatic molecular dynamics. We focused on CO photodissociation and recombination of CO to wild type (WT) and H64Q Ngb. Our results demonstrate that the distribution of CO within the proteins differs substantially due to rearrangement of amino acids surrounding the distal heme pocket. This leads to the decrease of the distal pocket volume in H64Q Ngb in comparison to WT Ngb, trapping migrating CO molecules in the distal pocket. We show that the mutation implicates the shortening of the time scale of CO geminate recombination, making H64Q Ngb 2.7 times more frequent binder than WT Ngb.
FTIR study of carbon monoxide adsorption on ion-exchanged X, Y and mordenite type zeolites
Directory of Open Access Journals (Sweden)
R. HERCIGONJA
2003-05-01
Full Text Available In this work Fourier transform infrared (FTIR study has been applied to study the adsorption of carbon monoxide on transition metal (Mn+, Co2+, Ni2+ ion-exchanged zeolites type Y, X and mordenites. The adsorption of CO at room temperature produces overlapping IR absorption bands in the 21202200 cm-1 region. The frequency of the band around 2200 cm-1 is found to be dependent not only on the charge-balancing transition metal cation, but also on the framework composition. The frequencies of the band near 1600 cm-1 was found to be dependent on the Si/Al ratio of the investigated zeolites.
PFS/Mars Express first results: water vapour and carbon monoxide global distribution
Ignatiev, N. I.; Titov, D. V.; Formisano, V.; Moroz, V. I.; Lellouch, E.; Encrenaz, Th.; Fouchet, T.; Grassi, D.; Giuranna, M.; Atreya, S.; Pfs Team
Planetary Fourier Spectrometer onboard Mars Express, with its wide spectral range (1.2--45 um) and high spectral resolution (1.4 cm-1), makes it possible to study in a self-consistent manner the Martian atmosphere by means of simultaneous analysis of spectral features in several spectral regions. As concerned small species, we observe 30--50, 6.3, 2.56, 1.87 and 1.38 μ m H2O bands, and 4.7 and 2.35 μ m CO bands. The most favourable, with respect to the instrument performance, 2.56 μ m H2O and 4.7 μ m CO bands, are used to study the variations of column abundance of water vapour and carbon monoxide on a global scale from pole to pole. All necessary atmospheric parameters, namely temperature profiles, surface pressure, and dust density are obtained from the same spectra, whenever possible.
Carbon monoxide poisoning at motels, hotels, and resorts.
Weaver, Lindell K; Deru, Kayla
2007-07-01
Each year, more than 200 people in the United States die from carbon monoxide (CO) poisoning. Poisoning has occurred at motels, hotels, and resorts. Congressional mandate requires smoke alarms in all guest rooms; however, smoke alarms do not detect CO. Data on patients poisoned at hotels, motels, and resorts were evaluated at a hyperbaric medicine service. In 2005, legal databases and online news databanks were searched to discover additional incidents. Only victims evaluated in hospitals or declared dead at the scene were included. Cases of intentional poisoning and poisoning from fires were excluded. Between 1989 and 2004, 68 incidents of CO poisoning occurring at hotels, motels, and resorts were identified, resulting in 772 accidentally poisoned: 711 guests, 41 employees or owners, and 20 rescue personnel. Of those poisoned, 27 died, 66 had confirmed sequelae, and 6 had sequelae resulting in a jury verdict. Lodging-operated, faulty room heating caused 45 incidents, pool/spa boilers 16, CO entrained from outdoors 5, and unreported sources caused 2 incidents. Public verdicts have averaged $4.8 million per incident (range, $1 million to $17.5 million). Poisoning occurred at hotels of all classes. Despite these incidents, most properties did not install CO alarms, and requirements for CO alarms at hotels, motels, and resorts are rare. Guests of motels, hotels, and resorts remain at risk for injury or death from CO poisoning. Measures to prevent CO poisoning of guests and employees of the lodging industry should be evaluated.
International Nuclear Information System (INIS)
Sumijanto; Sriyono
2016-01-01
Carbon monoxide is a species that is difficult to be separated from the reactor coolant helium because it has a relatively small molecular size. So it needs a process of conversion from carbon monoxide to carbondioxide. The rate of conversion of carbon monoxide in the purification system is influenced by several parameters including concentration, temperature and mass flow rate. In this research, optimization of the mass flow rate in coolant purification of RGTT200K for carbon monoxide conversion process was done. Optimization is carried out by using software Super Pro Designer. The rate of reduction of reactant species, the growth rate between the species and the species products in the conversion reactions equilibrium were analyzed to derive the mass flow rate optimization of purification for carbon monoxide conversion process. The purpose of this study is to find the mass flow rate of purification for the preparation of the basic design of the RGTT200K coolant helium purification system. The analysis showed that the helium mass flow rate of 0.6 kg/second resulted in an un optimal conversion process. The optimal conversion process was reached at a mass flow rate of 1.2 kg/second. A flow rate of 3.6 kg/second – 12 kg/second resulted in an ineffective process. For supporting the basic design of the RGTT200K helium purification system, the mass flow rate for carbon monoxide conversion process is suggested to be 1.2 kg/second. (author)
CSIR Research Space (South Africa)
Du Plessis, A
2007-01-01
Full Text Available The four carbon monoxide (CO) isotopomers 12C16O, 13C16O, 12C18O and 12C17O have been detected simultaneously in a CO gas sample of natural isotopic abundance by measuring rovibronic excitation spectra of six vibronic bands in the Fourth Positive...
Directory of Open Access Journals (Sweden)
H. E. Reader
2012-11-01
Full Text Available The photochemical oxidation of oceanic dissolved organic carbon (DOC to carbon monoxide (CO and carbon dioxide (CO2 has been estimated to be a significant process with global photoproduction transforming petagrams of DOC to inorganic carbon annually. To further quantify the importance of these two photoproducts in coastal DOC cycling, 38 paired apparent quantum yield (AQY spectra for CO and CO2 were determined at three locations along the coast of Georgia, USA over the course of one year. The AQY spectra for CO2 were considerably more varied than CO. CO AQY spectra exhibited a seasonal shift in spectrally integrated (260 nm–490 nm AQY from higher efficiencies in the autumn to less efficient photoproduction in the summer. While full-spectrum photoproduction rates for both products showed positive correlation with pre-irradiation UV-B sample absorption (i.e. chromophoric dissolved organic matter, CDOM as expected, we found no correlation between AQY and CDOM for either product at any site. Molecular size, approximated with pre-irradiation spectral slope coefficients, and aromatic content, approximated by the specific ultraviolet absorption of the pre-irradiated samples, were also not correlated with AQY in either data set. The ratios of CO2 to CO photoproduction determined using both an AQY model and direct production comparisons were 23.2 ± 12.5 and 22.5 ± 9.0, respectively. Combined, both products represent a loss of 2.9 to 3.2% of the DOC delivered to the estuaries and inner shelf of the South Atlantic Bight yearly, and 6.4 to 7.3% of the total annual degassing of CO2 to the atmosphere. This result suggests that direct photochemical production of CO and CO2 is a small, yet significant contributor to both DOC cycling and CO2 gas exchange in this coastal system.
TRACING H2 COLUMN DENSITY WITH ATOMIC CARBON (C I) AND CO ISOTOPOLOGS
International Nuclear Information System (INIS)
Lo, N.; Bronfman, L.; Cunningham, M. R.; Jones, P. A.; Lowe, V.; Cortes, P. C.; Simon, R.; Fissel, L.; Novak, G.
2014-01-01
We present the first results of neutral carbon ([C I] 3 P 1 - 3 P 0 at 492 GHz) and carbon monoxide ( 13 CO, J = 1-0) mapping in the Vela Molecular Ridge cloud C (VMR-C) and the G333 giant molecular cloud complexes with the NANTEN2 and Mopra telescopes. For the four regions mapped in this work, we find that [C I] has very similar spectral emission profiles to 13 CO, with comparable line widths. We find that [C I] has an opacity of 0.1-1.3 across the mapped region while the [C I]/ 13 CO peak brightness temperature ratio is between 0.2 and 0.8. The [C I] column density is an order of magnitude lower than that of 13 CO. The H 2 column density derived from [C I] is comparable to values obtained from 12 CO. Our maps show that C I is preferentially detected in gas with low temperatures (below 20 K), which possibly explains the comparable H 2 column density calculated from both tracers (both C I and 12 CO underestimate column density), as a significant amount of the C I in the warmer gas is likely in the higher energy state transition ([C I] 3 P 2 - 3 P 1 at 810 GHz), and thus it is likely that observations of both the above [C I] transitions are needed in order to recover the total H 2 column density
Review: hemodynamic response to carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Penney, D.G.
1988-04-01
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.
Occupational carbon monoxide poisoning in the State of Washington, 1994-1999.
Lofgren, Don J
2002-04-01
Carbon monoxide poisonings continue to be significant and preventable for a number of work operations. This study assesses occupational carbon monoxide morbidity and mortality for the state of Washington based on a review of workers' compensation records for the years 1994-1999. The study characterizes sources, industries, and causative factors, and further attempts to identify work operations most at risk. Records were identified by both injury source and diagnostic codes. The study limits itself to non-fire-related carbon monoxide poisonings and primarily those from acute exposure. A decline in the number of claims was not evident, but the number of incidents per year showed a slight decline. Carbon monoxide poisonings were found to occur throughout all types of industries. The greatest number of claims was found in agriculture, followed by construction and wholesale trade, with these three accounting for more than half the claims and nearly half of the incidents. The more severe poisonings did not necessarily occur in industries with the greatest number of incidents. The major source for carbon monoxide poisoning was forklift trucks, followed by auto/truck/bus, portable saws, and more than 20 other sources. Fruit packing and storage had the highest number of incidents mostly due to fuel-powered forklift activity, with nearly half of the incidents occurring in cold rooms. Adverse health effects as measured by carboxyhemoglobin, hyperbaric oxygen treatment, unconsciousness, and number and cost of claims were indexed by source. Though several specific work operations were identified, the episodic nature of carbon monoxide poisonings, as well as the diverse industries and sources, and the opportunity for a severe poisoning in any number of operations, poses challenges for effective intervention.
Reaction of uranium oxides with chlorine and carbon or carbon monoxide to prepare uranium chlorides
Energy Technology Data Exchange (ETDEWEB)
Haas, P.A.; Lee, D.D.; Mailen, J.C.
1991-11-01
The preferred preparation concept of uranium metal for feed to an AVLIS uranium enrichment process requires preparation of uranium tetrachloride (UCI{sub 4}) by reacting uranium oxides (UO{sub 2}/UO{sub 3}) and chlorine (Cl{sub 2}) in a molten chloride salt medium. UO{sub 2} is a very stable metal oxide; thus, the chemical conversion requires both a chlorinating agent and a reducing agent that gives an oxide product which is much more stable than the corresponding chloride. Experimental studies in a quartz reactor of 4-cm ID have demonstrated the practically of some chemical flow sheets. Experimentation has illustrated a sequence of results concerning the chemical flow sheets. Tests with a graphite block at 850{degrees}C demonstrated rapid reactions of Cl{sub 2} and evolution of carbon dioxide (CO{sub 2}) as a product. Use of carbon monoxide (CO) as the reducing agent also gave rapid reactions of Cl{sub 2} and formation of CO{sub 2} at lower temperatures, but the reduction reactions were slower than the chlorinations. Carbon powder in the molten salt melt gave higher rates of reduction and better steady state utilization of Cl{sub 2}. Addition of UO{sub 2} feed while chlorination was in progress greatly improved the operation by avoiding the plugging effects from high UO{sub 2} concentrations and the poor Cl{sub 2} utilizations from low UO{sub 2} concentrations. An UO{sub 3} feed gave undesirable effects while a feed of UO{sub 2}-C spheres was excellent. The UO{sub 2}-C spheres also gave good rates of reaction as a fixed bed without any molten chloride salt. Results with a larger reactor and a bottom condenser for volatilized uranium show collection of condensed uranium chlorides as a loose powder and chlorine utilizations of 95--98% at high feed rates. 14 refs., 7 figs., 14 tabs.
Zr powder and Zr-16% Al alloy as getters for O sub 2 , H sub 2 , H sub 2 O, CO and CO sub 2 gases
Energy Technology Data Exchange (ETDEWEB)
Garg, S P [CRM Jat Coll., Hisar (India); Gulbransen, E A [Pittsburgh Univ., PA (USA); Vijendran, P [Bhabha Atomic Research Centre, Bombay (India)
1990-01-01
Both zirconium and its 16 wt% aluminium alloy react with the common gases O{sub 2}, H{sub 2}, H{sub 2}O, CO and CO{sub 2} to form zirconium oxide, hydride and carbide or carbon and a thermochemical and stoichiometric analysis has been made of the several reactions. The capacity and reactivity of 30-40 {mu} zirconium powder and pellets of a 16 wt% aluminium-zirconium alloy, ST 101 getter, were studied using a sensitive vacuum microbalance, a mass spectrometer and Debye-Scherrer X-ray diffraction. The direct hydrogen reaction at 400{sup 0}C and 10 torr pressure and a slow oxidation reaction at 250-600{sup 0}C were used to measure the availability of the materials (capacity) for getter reactions. Special care must be taken to remove water vapour and any other reactive gas from the vacuum system in using the hydrogen method. The hydrogen-getter reaction must be carried out well below 400{sup 0}C if hydrogen is to be removed completely. The reactivity of water vapour in the presence of 10 torr of hydrogen gas was studied at 400{sup 0}C. Fourteen micrograms of water vapour in the reaction system could be detected. The carbon monoxide and carbon dioxide-getter reactions were studied at 500{sup 0}C and 600{sup 0}C at 10 torr pressure. Zirconium powder reacts much faster with both gases as compared to that with St 101 getter, activity of which with oxygen has been stabilized by adding aluminium. Carbon monoxide is produced in the carbon dioxide-getter reaction under conditions of excess gas in the reaction. Carbon and carbide were not observed in the carbon monoxide-getter reaction under excess gas conditions. (author).
The Effect of Carbon Monoxide Poisoning on Platelet Volume in Children
Directory of Open Access Journals (Sweden)
Halise Akça
2017-04-01
Full Text Available Introduction: Carbon monoxide poisoning is one of the most important causes of morbidity and mortality. There is increasing evidence supporting the important role of mean platelet volume (MPV as a marker of hypoxia and inflammation. In this study, we aimed to determine changes in MPV values in pediatric patients with carbon monoxide poisoning. Methods: We retrospectively evaluated children who were diagnosed with carbon monoxide poisoning in our hospital between January 2005 and 2014. Results: We included 228 children with carbon monoxide poisoning (49% male in this retrospective, controlled study. The mean age of the patients was 88±56 months. Control group consisted of 200 age-matched healthy children. There was no statistically significant difference in MPV levels between the study and control groups (8.43±1.1 fL and 8.26±0.7 fL, respectively. No correlation of MPV and platelet count with carboxyhemoglobin (COHb was found. Conclusion: In our study, it was determined that MPV value was not a helpful parameter for predicting the diagnosis of acute carbon monoxide poisoning in childhood. The difference between the MPV values and the lack of significance and the absence of correlation between MPV value and COHb level led to the fact that MPV was not a guide indicating the clinical severity of the condition.
National Aeronautics and Space Administration — MAPS Overview The MAPS experiment measures the global distribution of carbon monoxide (CO) mixing ratios in the free troposphere. Because of MAPS' previous flights...
Directory of Open Access Journals (Sweden)
Xiaodan Xu
2017-01-01
Full Text Available Objective. To observe the protective effect of edaravone (Eda on astrocytes after prolonged exposure to carbon monoxide (CO and further to investigate the potential mechanisms of Eda against CO-induced apoptosis. Methods. The rat primary cultured astrocytes were cultured in vitro and exposed to 1% CO for 24 h after being cultured with different concentrations of Eda. MTT assay was used to detect the cytotoxicity of CO. Flow cytometry was used to detect the apoptosis rate, membrane potential of mitochondria, and ROS level. The mRNA and protein expressions of Bcl-2, Bax, and caspase-3 were assessed by real-time PCR and Western blotting analysis, respectively. Results. Eda can significantly suppress cytotoxicity of CO, and it can significantly increase membrane potential of mitochondria and Bcl-2 expressions and significantly suppress the apoptosis rate, ROS level, Bax, and caspase-3 expressions. Conclusion. Eda protects against CO-induced apoptosis in rat primary cultured astrocytes through decreasing ROS production and subsequently inhibiting mitochondrial apoptosis pathway.
International Nuclear Information System (INIS)
Moloy, K.G.; Marks, T.J.
1984-01-01
Reported are results of the synthesis, characterization, and carbon monoxide chemistry of a series of sterically hindered thorium alkyls and hydrides of the type Cp' 2 Th(R)(X) (Cp' = eta 5 -C 5 Me 5 ) where R = H, D, methyl, eta-butyl, and CH 2 -t-Bu and X = OCH-t-Bu 2 , OC 6 H 3 -2,6-t-Bu 2 , and O-t-Bu. In addition, improved syntheses of the known complexes [Cp' 2 Th(μ-H)(H)] 2 , Cp' 2 Th(O-t-Bu)(Cl) and Cp' 2 Th(CH 2 -t-Bu)(Cl) are presented. The alkyl complexes undergo facile, irreversible carbonylation to yield eta 2 -acyls that were characterized by a variety of methods. Infrared Ir and 13 C NMR spectra of these complexes demonstrate that strong meta-(acyl)oxygen bonding takes place, fostering a pronounced carbene-like character. Thus, these complexes are characterized by low C-O Ir infrared stretching frequencies (nu/sub CO/ = 1450-1480 cm -1 ) and low-field 13 C NMR chemical shifts (delta/sub 13 C/ 355-370). The hydrides undergo a rapid, reversible, migratory CO insertion to yield formyls that have been characterized spectroscopically at low temperature. Infrared Ir and 13 C NMR spectra of these species are similar to the corresponding acyls, suggesting an analogous eta 2 structure. Variable-temperature equilibrium data show that the insertion of CO into thorium-hydrogen bonds is exothermic by ca. 5 kcal/mol, and this value is compared to that for the analogous alkyls. The equilibrium was also found to exhibit a distinct equilibrium isotope effect upon deuterium substitution, K/sub H//K/sub D/ = 0.31 at -78 0 C. The carbonylation of the complex Cp' 2 Th(n-Bu)(OCH-t-Bu 2 ) was found to obey a second-order rate law where rate = kP/sub CO/ [complex]. The insertion of CO into the Th-H bond of Cp' 2 Th(H)(OCH-t-Bu 2 ) was found by NMR methods to be first order in metal hydride. 55 references, 3 figures, 6 tables
UV-induced carbon monoxide emission from sand and living vegetation
DEFF Research Database (Denmark)
Bruhn, Dan; Albert, Kristian Rost; Mikkelsen, Teis Nørgaard
2012-01-01
The global burden of carbon monoxide, CO, is rather uncertain. In this paper we address the potential of UV-induced CO emission by terrestrial surfaces. Real-time measurements of [CO] were made with a cavity enhanced laser connected in closed loop to either an ecosystem chamber or a leaf scale...... chamber. Sand and leaves of all examined plant species exhibited emission of CO in response to artificial UV-radiation and the UV-component of natural solar radiation. The UV-induced rate of CO emission exhibited a rather low dependence on temperature, indicating an abiotic process. The emission of CO...... in response to the UV-component of natural solar radiation was also evident at the ecosystem scale. When scaled to the global level, the UV-induced emission of CO by the major types of terrestrial surfaces, living leaves and soil (here represented by sand), amounts up to 28 Tg yr−1. This source has...
General circulation model study of atmospheric carbon monoxide
International Nuclear Information System (INIS)
Pinto, J.P.; Yung, Y.L.; Rind, D.; Russell, G.L.; Lerner, J.A.; Hansen, J.E.; Hameed, S.
1983-01-01
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 15 g yr -1 , in addition to sources from incomplete combustion of fossil fuels and oxidation of methane. The globally averaged OH concentration calculated in the model is 7 x 10 5 cm -3 . Models that calculate globally averaged OH concentrations much lower than our 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
Digit and letter alexia in carbon monoxide poisoning
Institute of Scientific and Technical Information of China (English)
Qingyu Shen; Xiaoming Rong; Rui Pan; Ying Peng; Wei Peng; Yamei Tang
2012-01-01
This study examined a 24-year-old patient with delayed encephalopathy, who was admitted to hospital with complaints of headache and visual impairment 1 week after acute carbon monoxide poisoning. The results of a visual field assessment, electroencephalography and head magnetic resonance imaging indicated damage to the cerebral cortex. After a 2-week treatment period, the patient had recovered from the visual impairment, but exhibited digit- and letter-reading difficulty. The Chinese aphasia battery and the number and letter battery supplement were conducted. The results revealed that the patient exhibited digit and letter alexia, while the ability to read Chinese characters was preserved. In contrast, the patient exhibited a deficit in Chinese character writing, while number and letter writing remained intact. Following treatment, reading and writing ability was improved and electroencephalographic abnormalities were ameliorated. Overall, our experimental findings demonstrated that delayed encephalopathy following acute carbon monoxide poisoning was characterized by digit and letter alexia.
Rella, C.; Jacobson, G.
2012-04-01
The ability to quantify the sources and sinks of carbon dioxide on the urban scale is essential for understanding the atmospheric drivers to global climate change. In the 'top-down' approach, overall carbon fluxes are determined by combining remote measurements of carbon dioxide concentrations with complex atmospheric transport models, and these emissions measurements are compared to "bottoms-up" predictions based on detailed inventories of the sources and sinks of carbon, both anthropogenic and biogenic in nature. This approach, which has been proven to be effective at continental scales, becomes challenging to implement at the urban scale, due to poorly understood micrometeorological atmospheric transport models and high variability of the emissions sources in space (e.g., factories, highways, residences) and time (rush hours, factory shifts and shutdowns, residential energy usage variability during the day and over the year). New measurement and analysis techniques are required to make sense of the carbon dioxide signal in cities. Here we present detailed, high spatial- and temporal-resolution greenhouse gas measurements in Silicon Valley in California. The synthesis of two experimental campaigns is presented: real-time measurements from two ten-meter urban 'towers,' and ground-based mobile mapping measurements. Real-time carbon dioxide data from a nine-month period are combined with real-time carbon monoxide, methane, acetylene, and carbon 13 measurements to partition the observed CO2 concentrations between different anthropogenic sectors (e.g., transport, residential) and biogenic sources. The carbon monoxide to carbon dioxide ratio is shown to vary over more than a factor of two from season to season or even from day to night, indicating rapid and frequent shifts in the balance between different carbon dioxide sources. Clear differences are seen between the two urban sites, which are separated by 7 km. Further information is given by the carbon 13 signature
Carbon monoxide may be an important molecule in migraine and other headaches
DEFF Research Database (Denmark)
Arngrim, Nanna; Schytz, Henrik W; Hauge, Mette K
2014-01-01
INTRODUCTION: Carbon monoxide was previously considered to just be a toxic gas. A wealth of recent information has, however, shown that it is also an important endogenously produced signalling molecule involved in multiple biological processes. Endogenously produced carbon monoxide may thus play...
1994-04-01
During aircraft interior fires, carbon monoxide (CO) and hydrogen cyanide (HCN) are produced in sufficient amounts to cause incapacitation and death. Time-to-incapacitation (ti) is a practical parameter for estimating escape time in fire environments...
Cyclic process for producing methane from carbon monoxide with heat removal
Frost, Albert C.; Yang, Chang-lee
1982-01-01
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.
Energy Technology Data Exchange (ETDEWEB)
Apte, Michael G. [Univ. of California, Berkeley, CA (United States)
1997-09-01
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°C to 30°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.
Retinal venous blood carbon monoxide response to bright light in male pigs: A preliminary study.
Oren, Dan A; Duda, Magdalena; Kozioł, Katarzyna; Romerowicz-Misielak, Maria; Koziorowska, Anna; Sołek, Przemysław; Nowak, Sławomir; Kulpa, Magdalena; Koziorowski, Marek
2017-03-01
The physical mechanism by which light is absorbed in the eye and has antidepressant and energizing effects in Seasonal Affective Disorder and other forms of psychiatric major depression is of scientific interest. This study was designed to explore one specific aspect of a proposed humoral phototransduction mechanism, namely that carbon monoxide (CO) levels increase in retinal venous blood in response to bright light. Eleven mature male pigs approximately six months of age were kept for 7days in darkness and fasted for 12h prior to surgery. Following mild sedation, anesthesia was induced. Silastic catheters were inserted into the dorsal nasal vein through the angular vein of the eye to reach the ophthalmic sinus, from which venous blood outflowing from the eye area was collected. The animals were exposed to 5000lx of fluorescent-generated white light. CO levels in the blood were analyzed by gas chromatography before and after 80min of light exposure. At baseline, mean CO levels in the retinal venous blood were 0.43±0.05(SE)nmol/ml. After bright light, mean CO levels increased to 0.54±0.06nmol/ml (two-tailed t-test plight exposure raises carbon monoxide levels in ophthalmic venous blood. Copyright © 2017 Elsevier B.V. All rights reserved.
Kawagucci, S.; Narita, T.; Obata, H.; Ogawa, H.; Gamo, T.
2009-12-01
Biological nitrogen fixation is a key metabolism controlling marine N-cycling and also known as a main H2 source. Recently, it was proposed that a monitoring of surface H2 concentration could be used quickly to figure out the spatial extent of biological nitrogen fixation activity without onboard incubation required for currently used methods for detecting the activity. However, H2 behavior in ocean water was still unresolved. This study carried out vertical observation of H2 and CO concentrations in south of Japan, western North Pacific. Because carbon monoxide, CO, in seawater has no relation with nitrogen fixation metabolism and is produced dominantly by the photochemical reaction, which is an altanative H2 source, simultaneous observation and comparison of H2 and CO concentration is helpful to investigate H2 behavior in ocean water. Reductive gases in seawater were observed during the R/V Tansei-maru KT-08-14 cruise by using a wired CTD-CMS (CTD-carousel multiple sampling) system to conduct vertical sampling (at most 200 m depth) and by using a plastic bucket for sampling surface seawater. The sample in the Niskin-X bottle was directed to the bottom of a 120 mL brown-colored glass vial allowed to overflow by 2 volumes before the tube was slowly withdrawn. After the addition of 0.5 mL HgCl2-saturated solution for poisoning, the PTFE-lined butyl-gum septum was used to cap the vials. Molecular hydrogen (H2) and carbon monoxide (CO) were analyzed at an onboard laboratory within 6 hours after subsampling. 20 mL of sample water was substituted by 20 mL of H2- and CO-free air using a gas-tight syringe; then the vial was put on an automatic shaker and shaken upside down for 6 minutes to achieve a complete equilibrium between the dissolved and head space gases in the vial. The equilibrated headspace was taken by another gas-tight syringe and then injected into a gas chromatograph equipped with a trace reduced gas detector. Vertical distribution of dissolved H2 and CO
Carbon Monoxide Hydrogenation on Ice Surfaces.
Kuwahata, Kazuaki; Ohno, Kaoru
2018-03-14
We have performed density functional calculations to investigate the carbon monoxide hydrogenation reaction (H+CO→HCO), which is important in interstellar clouds. We found that the activation energy of the reaction on amorphous ice is lower than that on crystalline ice. In the course of this study, we demonstrated that it is roughly possible to use the excitation energy of the reactant molecule (CO) in place of the activation energy. This relationship holds also for small water clusters at the CCSD level of calculation and the two-layer-level ONIOM (CCSD : X3LYP) calculation. Generally, since it is computationally demanding to estimate activation energies of chemical reactions in a circumstance of many water molecules, this relationship enables one to determine the activation energy of this reaction on ice surfaces from the knowledge of the excitation energy of CO only. Incorporating quantum-tunneling effects, we discuss the reaction rate on ice surfaces. Our estimate that the reaction rate on amorphous ice is almost twice as large as that on crystalline ice is qualitatively consistent with the experimental evidence reported by Hidaka et al. [Chem. Phys. Lett., 2008, 456, 36.]. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Adsorption of CO, CO2, H2, and H2O on titania surfaces with different oxidation states
International Nuclear Information System (INIS)
Raupp, G.B.; Dumesic, J.A.
1985-01-01
The adsorptive properties of titania surfaces with different oxidation states were proved by temperature-programmed desorption (TPD) of CO, H 2 , CO 2 , and H 2 O. Auger electron spectroscopy and X-ray photoelectron spectroscopy revealed that vacuum annealing an oxidized titanium foil at temperatures from 300 to 800 K was an effective means of systematically varying the average surface oxidation state from Ti 4+ to Ti 2+ . Carbon monoxide weakly adsorbed (desorption energy of 44-49 kJ x mol -1 ) in a carbonyl fashion on coordinatively unsaturated cation sites. Titania surfaces were inert with respect to H 2 adsorption and dissociation. Carbon dioxide adsorbed in a linear molecular fashion. Water adsorbed both molecularly and dissociatively. Results are discussed in terms of the role of titania oxidation state in CO hydrogenation over titania-supported metal catalysts. 74 references, 7 figures
Generation rate of carbon monoxide from CO2 arc welding.
Ojima, Jun
2013-01-01
CO poisoning has been a serious industrial hazard in Japanese workplaces. Although incomplete combustion is the major cause of CO generation, there is a risk of CO poisoning during some welding operations. The aim of the present study was to evaluate the generation rate of CO from CO2 arc welding under controlled laboratory conditions and estimate the ventilation requirements for the prevention of CO poisoning. Bead on plate welding was carried out with an automatic welding robot on a rolled steel base metal under several conditions. The concentration of emitted CO from the welding was measured by a real-time CO monitor in a well-ventilated laboratory that was free from ambient CO contamination. The generation rate of CO was obtained from the three measurements-the flow rate of the welding exhaust gas, CO concentration in the exhaust gas and the arcing time. Then the ventilation requirement to prevent CO poisoning was calculated. The generation rate of CO was found to be 386-883 ml/min with a solid wire and 331-1,293 ml/min with a flux cored wire respectively. It was found that the CO concentration in a room would be maintained theoretically below the OSHA PEL (50 ppm) providing the ventilation rate in the room was 6.6-25.9 m3/min. The actual ventilation requirement was then estimated to be 6.6-259 m3/min considering incomplete mixing. In order to prevent CO poisoning, some countermeasures against gaseous emission as well as welding fumes should be taken eagerly.
Directory of Open Access Journals (Sweden)
Magdalena Sowa
2015-04-01
owa kluczowe: tlenek węgla, zatrucie, hipoksja. Abstract Introduction: Carbon monoxide (CO is a colorless, odorless, non-irritating and toxic gas, undetectable by the sense organs. CO is a product of incomplete combustion of substances containing hydrocarbon products (industrial gas, coal, wood. Carbon monoxide is one of the most common causes of poisoning inhalation in the world. Aim of the study: The aim of this study was to analyze the routes of exposure, clinical manifestation and treatment of carbon monoxide poisoning. Brief overview of the state of knowledge: The toxicity of carbon monoxide is strongly associated with its high affinity for hemoglobin (approximately 200 times greater than the oxygen. The heart and central nervous system (CNS are the most vulnerable to CO. Pathomechanism of action involves binding of carbon monoxide with iron atom in the heme molecule to form a compound called carboxyhemoglobin (COHb. Inhaling carbon monoxide-rich air may cause anoxia. The oxidative metabolic processes are inhibited. Accumulation of acidic metabolites cause the enlargement of the cerebral arteries and consequently hyperemia of the brain. Summary: The amount of carbon monoxide poisoning in Poland is higher than in other European countries. Significant decrease mortality for carbon monoxide poisoning has observed over the last few years. Thousands of patients who lose their health and their lives, should cause the attention to the effectiveness of preventive measures. Keywords: carbon monoxide, poisoning, hypoxia.
Carbon monoxide poisoning in children riding in the back of pickup trucks.
Hampson, N B; Norkool, D M
OBJECTIVE - To describe the case characteristics of a series of children poisoned with carbon monoxide while traveling in the back of pickup trucks. DESIGN - 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. SETTING - A private, urban, tertiary care center in Seattle, Wash. PATIENTS - Twenty children ranging from 4 to 16 years of age. INTERVENTION - All patients were treated with hyperbaric oxygen. MAIN OUTCOME MEASURES - Characteristics of the poisoning incident and clinical patient outcome. RESULTS - 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% +/- 2.4% (mean +/- 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. CONCLUSIONS - Carbon monoxide poisoning is a significant hazard for children who ride in the back of pickup trucks. If possible, this practice should be avoided.
Catalytic Copolymerization of Ethene and Carbon Monoxide on Nickel Complexes.
Domhöver, Bernd; Kläui, Wolfgang; Kremer-Aach, Andreas; Bell, Ralf; Mootz, Dietrich
1998-11-16
Can palladium be replaced by nickel? For the industrial copolymerization of carbon monoxide and ethene a palladium catalyst is used which cannot be recovered-a cheaper procedure would be desirable. The presented complex 1 is the first structurally characterized nickel compound which does not polymerize ethene but a mixture from carbon monoxide and ethene unter mild conditions to give a perfectly alternating polyketone. © 1998 WILEY-VCH Verlag GmbH, Weinheim, Fed. Rep. of Germany.
CROSS-CORRELATIONS AS A COSMOLOGICAL CARBON MONOXIDE DETECTOR
International Nuclear Information System (INIS)
Pullen, Anthony R.; Doré, Olivier; Chang, Tzu-Ching; Lidz, Adam
2013-01-01
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 Lyα-emitter sample, for which a signal-to-noise ratio of 58 is possible.
Composition and color stability of carbon monoxide treated dried porcine blood.
Fontes, P R; Gomide, L A M; Fontes, E A F; Ramos, E M; Ramos, A L S
2010-07-01
Color stability of swine blood was studied over 12 weeks of storage in plastic bags, after pH (7.40, 6.70, or 6.00) adjustment, saturation with carbon monoxide (CO) and spray-drying. CO-treated dried blood presented a redder color and higher reflectance between 610 and 700 nm, compared to a brownish-red color and lower reflectance of untreated samples. As indicated by reflectance spectra, blood pH adjustment did not influence (P>0.05) the initial color of dried blood but influenced (Pvalues, which was more pronounced in polyethylene (OTR=4130 cm(3)/m(2)/day/atm) packaged samples. After 12 weeks of storage, CO-treated samples packaged in high OTR bags presented color indexes similar to those of the untreated dried samples. CO-treated samples packaged in nylon-polyethylene (OTR=30-60 cm(3)/m(2)/day/atm) bags showed a smaller rate of discoloration and color difference (DeltaE(*)) between the CO-treated and untreated samples. Even with some darkening, packaging CO-treated dry blood in low OTR bags still gives an acceptable reddish color after 12 weeks of storage while untreated dry blood has a brownish color just after drying. Copyright 2010 Elsevier Ltd. All rights reserved.
2010-07-01
....112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission... emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and nonmethane hydrocarbon are measured using... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Oxides of nitrogen, carbon monoxide...
Directory of Open Access Journals (Sweden)
T. L. Rakyts’ka
2015-11-01
Full Text Available In spite of a great number of patented formulas of catalysts for neutralization of carbon monoxide (CO which is the most widespread atmospheric pollutant, only batch-produced hopcalite and alumina supported palladium (Pd/Al2O3 are used in practice. The named catalysts have significant defects: hopcalite is poisonable in the presence of water vapor and Pd/Al2O3 is characterized by the great content of palladium. We have found the possibility of using inexpensive Ukrainian natural sorbents differing by their mineralogical and chemical compositions, i.e. zeolites, bentonites, basalt tuffs, and disperse silicas, as supports for development and subsequent application of palladium(II and copper(II based catalysts for carbon monoxide oxidation. Acid-thermally modified Ukrainian sorbents have been found to be proper for obtaining supported copper-palladium complexes the most catalytically active in the reaction. Application of Ukrainian natural tripolis permitted to avoid the step of acid-thermal modification complicating the technique of catalyst production. As was found, the origin and phase composition of tripolis affect the activity of catalysts supported on them in the reaction of low-temperature Co oxidation. The most active catalyst permitting sanitary purification of air from CO to a level permissible for atmosphere of populated areas have been obtained in the case of insignificantly (thermally or hydrothermally modified tripoli from Konoplianskoe deposit.
Foucault, surveillance, and carbon monoxide testing within stop-smoking services.
Grant, Aimee; Ashton, Kathryn; Phillips, Rhiannon
2015-07-01
Health professionals have adopted proactive testing for early evidence of disease. Researchers have identified that this leads to enumerated understandings and shapes behavior in productive ways. Smoking-cessation advisors regularly test clients for carbon monoxide (CO), but client views of this had not previously been explored. We interviewed 23 clients of a United Kingdom-based stop-smoking service regarding their experiences of CO testing. The majority of participants were successful quitters. We used ATLAS.ti 7 as a data-management tool during structured qualitative analysis. Our findings reveal that clients believed the results of their CO tests. Many became enumerated in their understanding, and thus placed themselves in a hierarchy with other members of their group. Almost all clients found that knowing their CO test score was motivating. We conclude that additional research is needed to understand the experiences of CO testing among clients who do not quit. © The Author(s) 2014.
Carbon monoxide apparent quantum yields and photoproduction in the Tyne estuary
Directory of Open Access Journals (Sweden)
A. Stubbins
2011-03-01
Full Text Available Carbon monoxide (CO apparent quantum yields (AQYs are reported for a suite of riverine, estuarine and sea water samples, spanning a range of coloured dissolved organic matter (CDOM sources, diagenetic histories, and concentrations (absorption coefficients. CO AQYs were highest for high CDOM riverine samples and almost an order of magnitude lower for low CDOM coastal seawater samples. CO AQYs were between 47 and 80% lower at the mouth of the estuary than at its head. Whereas, a conservative mixing model predicted only 8 to 14% decreases in CO AQYs between the head and mouth of the estuary, indicating that a highly photoreactive pool of terrestrial CDOM is lost during estuarine transit. The CDOM absorption coefficient (a at 412 nm was identified as a good proxy for CO AQYs (linear regression r2 > 0.8; n = 12 at all CO AQY wavelengths studied (285, 295, 305, 325, 345, 365, and 423 nm and across environments (high CDOM river, low CDOM river, estuary and coastal sea. These regressions are presented as empirical proxies suitable for the remote sensing of CO AQYs in natural waters, including open ocean water, and were used to estimate CO AQY spectra and CO photoproduction in the Tyne estuary based upon annually averaged estuarine CDOM absorption data. A minimum estimate of annual CO production was determined assuming that only light absorbed by CDOM leads to the formation of CO and a maximum limit was estimated assuming that all light entering the water column is absorbed by CO producing photoreactants (i.e. that particles are also photoreactive. In this way, annual CO photoproduction in the Tyne was estimated to be between 0.99 and 3.57 metric tons of carbon per year, or 0.004 to 0.014% of riverine dissolved organic carbon (DOC inputs to the estuary. Extrapolation of CO photoproduction rates to estimate total DOC photomineralisation indicate that less than 1% of DOC inputs are removed via photochemical processes during
2010-07-01
... carbon monoxide and by-product hydrogen production subcategory. 415.330 Section 415.330 Protection of... MANUFACTURING POINT SOURCE CATEGORY Carbon Monoxide and By-Product Hydrogen Production Subcategory § 415.330 Applicability; description of the carbon monoxide and by-product hydrogen production subcategory. The provisions...
Magnetic resonance imaging of carbon monoxide poisoning in chronic stage
International Nuclear Information System (INIS)
Kojima, Shigeyuki; Kawamura, Mitsuru; Shibata, Noriyuki; Takahashi, Nobuyoshi; Hirayama, Keizo
1986-01-01
Magnetic resonance imaging (MRI) was evaluated in three patients with carbon monoxide (CO) poisoning in chronic stage by comparison with serial X-ray computed tomography (CT). In Case 1 and 3, no pallidal lesions believed to be the most common lesion of the gray matter in CO poisoning were found in the serial X-ray CT scans. In the other case (Case 2), the typical initial bilateral symmetrical low density areas in the globus pallidus were found to have decreased markedly in size and finally disappeared in the latter X-ray CT scan. But MRI using inversion recovery (IR) or spin echo (SE) pulse sequence clearly showed bilateral symmetrical decreased or increased signal intensity areas in the globus pallidus in all three cases. In Case 3, chronic CO poisoning was confirmed by the bilateral symmetrical pallidal lesions on MRI, although differential diagnosis was difficult. Furthermore, in Case 2, with pure alexia, MRI using IR or SE pulse sequence demonstrated a patchy decreased or increased signal intensity area in the subcortical white matter at the left angular gyrus, although X-ray CT scan showed no abnormal findings. MRI is useful in the diagnosis of CO poisoning, especially chronic CO poisoning, because necrosis, cavitation, demyelination, gliosis and so on due to hypoxia of CO poisoning were sensitively detected from changes in the proton density and the T1 or T2 relaxation time value on MRI. (J.P.N.)
Four deaths due to carbon monoxide poisoning in car washes.
Carson, H J; Stephens, P J
1999-09-01
In a period of 13 months, three separate incidents of lethal carbon monoxide (CO) poisoning in closed car wash bays resulted in the deaths of 4 white men aged 20 to 36 years. Each man appears to have been intoxicated with mind-altering substances, which may impair judgment, perception of outside conditions, and self-awareness. All four died in winter months. For three men, the deaths were ruled accidental, and for the remaining man, the previous deaths appear to have provided a model for suicide. Warning signs may not be effective to prevent future CO deaths in car washes because of the possible role of intoxication. Mechanical or electronic methods to prevent a bay door from closing completely may be preferable.
International Nuclear Information System (INIS)
Rappaport, D.S.; Niewoehner, D.E.; Kim, T.H.; Song, C.W.; Levitt, S.H.
1983-01-01
Carbon monoxide uptake (V/sub co/) and ventilation rate (VR) of C3H mice were determined at 14 weeks following either X irradiation of lungs only or total-body irradiation with 60 Co at different dose rates. Following localized X irradiation of lung at 97 /sub c/Gy/min there was a reduction in V/sub co/, which was inversely related to radiation dose, with a small reduction below control levels being detected at 7 Gy, the lowest dose tested. An increase in VR could be detected only at doses of 11 Gy, or more. Another group of animals received 11.5 Gy total-body irradiation at either 26.2 or 4.85 /sub c/Gy/min fllowed by transplantation with syngeneic bone marrow. Following total-body irradiation, V/sub co/ was significantly reduced by about 37% at the higher dose rate and 23% at the lower dose rate. In contrast, a trend toward elevated VR was detected only at the higher dose rate.The results indicate that V/sub co/ is a sensitive indicator of radiation-induced lung injury and that under the experimental conditions used V/sub co/ is a more sensitive indicator of radiation-induced lung injury in C3H mice than VR
Energy Technology Data Exchange (ETDEWEB)
Lefebvre, B.; Chabot, L.; Gratton, J. [Direction de sante publique de Montreal, Montreal, PQ (Canada); Lacoursiere, D. [Quebec Ministere de la Sante et des Services sociaux du Quebec, Quebec, PQ (Canada)
2009-07-01
Quebec launched a public health campaign for the Montreal region to prevent carbon monoxide poisoning. The objectives of the campaign were to communicate the dangers of carbon monoxide poisoning, its potential sources, its effects on public health, and the means to prevent poisoning. Its purpose was to inform the public of the risks and strategies to be used in case of carbon monoxide poisoning and to lay out the merits of household carbon monoxide alarms. The communication was done by way of the media, in cooperation with community organizations and school boards. Other tools used in the campaign included the Internet, flyers and press releases. A poll taken in 2008 showed that 59 per cent of the respondents had one or more sources for carbon monoxide in their homes, including fireplaces, and that 28 per cent had a functioning alarm for carbon monoxide detection. A future survey will be held to follow-up on the evolution of the campaign. The development of various activities will help decrease the risk of carbon monoxide poisoning. tabs., figs.
Henstra, Anne M.; Stams, Alfons J. M.
2011-01-01
Carboxydothermus hydrogenoformans is a thermophilic strictly anaerobic bacterium that catalyses the water gas shift reaction, the conversion of carbon monoxide with water to molecular hydrogen and carbon dioxide. The thermodynamically favorable growth temperature, compared to existing industrial catalytic processes, makes this organism an interesting alternative for production of cheap hydrogen gas suitable to fuel CO-sensitive fuel cells in a future hydrogen economy, provided sufficiently lo...
Composite catalyst for carbon monoxide and hydrocarbon oxidation
Liu, Wei; Flytzani-Stephanopoulos, Maria
1996-01-01
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.
California Environmental Health Tracking Program — This dataset contains case counts, rates, and confidence intervals of unintentional carbon monoxide poisoning (CO) inpatient hospitalizations and emergency...
Energy Technology Data Exchange (ETDEWEB)
Uribe-Godinez, J.; Jimenez-Sandoval, O.; Borja-Arco, E.; Altamirano-Gutierrez, A. [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Queritaro (Mexico); Castellanos, R.H. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Queretaro, Queretaro (Mexico)
2008-07-01
Rhodium (Rh6(CO)16) and novel Rh-based clusters were prepared using thermolysis techniques under different conditions in N2 and H2 reaction media, as well as in n-nonane, o-xylene, 1,2-dichlorobenzene and dimethylsulfoxide. The clusters were used as novel electrocatalysts for oxygen reduction reaction (ORR) in the absence and presence of 1.0 and 2.0 M methanol solutions. The catalysts were also used for hydrogen oxidation reaction (HOR) with pure hydrogen (H2) and in the presence of carbon monoxide (CO). Rotating disk electrode measurements were used to analyze the materials. The study showed that the electrocatalyst support ratio plays a significant role in the electrochemical behaviour of the materials. Rh6(CO)16 and Rh2(1,2-DCB) presented the best electrocatalytic behaviour for ORR and HOR in the absence and presence of methanol and CO. The study demonstrated that the rhodium-based materials are capable of performing ORR and HOR while being tolerant of both methanol and CO. 3 refs., 3 figs.
Metal-Organic-Framework-Mediated Nitrogen-Doped Carbon for CO2 Electrochemical Reduction
Wang, Riming; Sun, Xiaohui; Ould-Chikh, Samy; Osadchii, Dmitrii; Bai, Fan; Kapteijn, Freek; Gascon, Jorge
2018-01-01
A nitrogen-doped carbon was synthesized through the pyrolysis of the well-known metal-organic framework ZIF-8, followed by a subsequent acid treatment, and has been applied as a catalyst in the electrochemical reduction of carbon dioxide. The resulting electrode shows Faradaic efficiencies to carbon monoxide as high as ∼78%, with hydrogen being the only byproduct. The pyrolysis temperature determines the amount and the accessibility of N species in the carbon electrode, in which pyridinic-N and quaternary-N species play key roles in the selective formation of carbon monoxide.
Metal-Organic-Framework-Mediated Nitrogen-Doped Carbon for CO2 Electrochemical Reduction
Wang, Riming
2018-04-11
A nitrogen-doped carbon was synthesized through the pyrolysis of the well-known metal-organic framework ZIF-8, followed by a subsequent acid treatment, and has been applied as a catalyst in the electrochemical reduction of carbon dioxide. The resulting electrode shows Faradaic efficiencies to carbon monoxide as high as ∼78%, with hydrogen being the only byproduct. The pyrolysis temperature determines the amount and the accessibility of N species in the carbon electrode, in which pyridinic-N and quaternary-N species play key roles in the selective formation of carbon monoxide.
The electric dipole moment of cobalt monoxide, CoO.
Zhuang, Xiujuan; Steimle, Timothy C
2014-03-28
A number of low-rotational lines of the E(4)Δ7/2 ← X(4)Δ7/2 (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h7/2, and the electron quadrupole parameter, eQq0, for the E(4)Δ7/2(υ = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, μ(→)(el), for the X(4)Δ7/2 (υ = 0) and E(4)Δ7/2 (υ = 1) states were determined to be 4.18 ± 0.05 D and 3.28 ± 0.05 D, respectively, from the analysis of the observed Stark spectra of F' = 7 ← F″ = 6 branch feature in the Q(7/2) line and the F' = 8 ← F″ = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed.
Place, P., Jr.; Petrenko, V. V.; Vimont, I.; Buizert, C.; Lang, P. M.; Edwards, J.; Harth, C. M.; Hmiel, B.; Mak, J. E.; Novelli, P. C.; Brook, E.; Weiss, R. F.; Vaughn, B. H.; White, J. W. C.
2014-12-01
Carbon Monoxide (CO) is an important atmospheric trace gas that affects the oxidative capacity of the atmosphere and contributes indirectly to climate forcing by being a major sink of tropospheric OH. A good understanding of the past atmospheric CO budget is therefore important for climate models attempting to characterize recent changes in the atmosphere. Previous work at NEEM, Greenland provided the first reconstructions of Arctic atmospheric history of CO concentration and stable isotope ratios (δC18O and δ13CO) from firn air, dating to the 1950s. In this new study, firn air was sampled from eighteen depth levels through the firn column at Summit, Greenland (in May 2013), yielding a second, independent record of Arctic CO concentration and isotopic ratios. Carbon monoxide stable isotope ratios were analyzed on replicate samples and using a newly developed system with improved precision allowing for a more robust reconstruction. The new CO concentration and stable isotope results overall confirm the earlier findings from NEEM, with a CO concentration peak around the 1970s and higher δC18O and δ13CO values associated with peak CO. Modeling and interpretation of the data are in progress.
Magnetic Resonance Imaging Findings in Chronic Carbon Monoxide Intoxication
Energy Technology Data Exchange (ETDEWEB)
Durak, A. C.; Coskun, A.; Yikilmaz, A.; Erdogan, F.; Mavili, E.; Guven, M. [Hospital of Erciyes Univ., Kayseri (Turkey). Dept. of Radiology
2005-05-01
Purpose: To define the cranial magnetic resonance imaging (MRI) features of the chronic stage of carbon monoxide (CO) poisoning in patients with and without neuropsychiatric sequelae. Material and Methods: Eight patients who had neither symptoms nor neurological sequelae and eight patients with neuropsychiatric sequelae were included in the study. Patients aged between 9 to 57 (mean 32.2 years). All patients had been comatose at initial admittance and awoke after normobaric 100% oxygen therapy within 1-7 days. In this study, the patients were being examined with routine cranial MRI between 1 and 10 years (mean 3.4 years) after exposure to CO. Results: The most common finding was bilateral symmetric hyperintensity of the white matter, which was more significant in the centrum semiovale, with relative sparing of the temporal lobes and anterior parts of the frontal lobes on T2-weighted and FLAIR images in all patients. Cerebral cortical atrophy was seen in 10 patients; mild atrophy of cerebellar hemispheres in 8; and vermian atrophy in 11. Corpus callosum was atrophic in one patient. Bilateral globus pallidus lesions were seen in three patients. The lesions were hypointense on T1-weighted images and hyperintense on T2-weighted and FLAIR images. Conclusion: Patients with severe CO intoxication may develop persistent cerebral changes independently of their neuropsychiatric findings in the chronic stage. They may present with characteristic MRI findings as described here, even if asymptomatic. The history of CO exposure is therefore helpful for recognizing and interpreting the MRI findings of chronic stage CO intoxication.
Directory of Open Access Journals (Sweden)
Tursunov Obid
2017-11-01
Full Text Available The thermal behaviour of the Rosa mutiflora biomass by thermogravimetric analysis was studied at heating rate 3 K min−1 from ambient temperature to 950 °C. TGA tests were performed in high purity carbon dioxide (99 998% with a flow rate 200 ml/min and 100 mg of sample, milled and sieved to a particle size below 250 µm. Moreover, yields of gasification products such as hydrogen (H2, carbon monoxide (CO and methane (CH4 were determined based on the thermovolumetric measurements of catalytic (Ni/Al2O3-SiO2 and Ni/Al2O3-SiO2 with K2O promoter catalysts and non-catalytic gasification of the Rosa multiflora biomass. Additionally, carbon conversion degrees are presented. Calculations were made of the kinetic parameters of carbon monoxide and hydrogen formation reaction in the catalytic and non-catalytic CO2 gasification processes. A high temperature of 950 °C along with Ni/Al2O3-SiO2and Ni/Al2O3-SiO2 with K2O promoter catalysts resulted in a higher conversion of Rosa multiflora biomass into gaseous yield production with greatly increasing of H2 and CO contents. Consequently, H2 and CO are the key factors to produce renewable energy and bio-gases (synthesis gas. The parameters obtained during the experimental examinations enable a tentative assessment of plant biomasses for the process of large-scale gasification in industrial sectors.
Pre-Combustion Capture of CO2 in IGCC Plants
Energy Technology Data Exchange (ETDEWEB)
NONE
2011-12-15
Pre-combustion capture involves reacting a fuel with oxygen or air and/or steam to give mainly a 'synthesis gas (syngas)' or 'fuel gas' composed of carbon monoxide and hydrogen. The carbon monoxide is reacted with steam in a catalytic reactor, called a shift converter, to produce CO2 and more hydrogen. CO2 is then separated, usually by a physical or chemical absorption process, resulting in a hydrogen-rich fuel which can be used in many applications, such as boilers, furnaces, gas turbines, engines and fuel cells. Pre-combustion capture is suitable for use in integrated gasification combined cycle (IGCC) plants especially since the CO2 partial pressures in the fuel gas are higher than in the flue gas. After the introduction there follows a short discussion of the water-gas shift (WGS) reaction. This is followed by chapters on the means of CO2 capture by physical and chemical solvents, solid sorbents, and membranes. The results and conclusions of techno-economic studies are introduced followed by a look at some of the pilot and demonstration plants relevant to pre-combustion capture in IGCC plants.
Emissions of CO2, CO, NOx, HC, PM, HFC-134a, N2O and CH4 from the global light duty vehicle fleet
Directory of Open Access Journals (Sweden)
Timothy J. Wallington
2008-04-01
Full Text Available Vehicles emit carbon dioxide (CO2, carbon monoxide (CO, nitrogen oxides (NOx, hydrocarbons (HC, particulate matter (PM, hydrofluorocarbon 134a (HFC-134a, methane (CH4, and nitrous oxide (N2O. An understanding of these emissions is needed in discussions of climate change and local air pollution issues. To facilitate such discussions an overview of past, present, and likely future emissions from light duty vehicles is presented. Emission control technologies have reduced the emissions of CO, VOCs, PM, HFC-134a, CH4, and N2O from modern vehicles to very low levels.
Study on the surface oxidation resistance of uranium metal in the atmosphere of carbon monoxide
International Nuclear Information System (INIS)
Wang Xiaolin; Fu Yibei; Xie Renshou
1999-01-01
The surface reactions of different layers on uranium metal with carbon monoxide at 25, 80 and 200 degree C are studied by X-ray photoelectron spectroscopy (XPS). The experimental results show that the carbon monoxide is adsorbed on the surface oxide layer of uranium and interacted each other. The content of oxygen in the surface oxide and O/U ratio are decreased with increasing the exposure of carbon monoxide to the surface layer. The effect of reduction on the metal surface is more obviously with a higher temperature and increasing of layer thickness. The investigation indicates the uranium metal has resistance to further oxidation in the atmosphere of carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.
1979-05-01
The tar, nicotine, carbon monoxide, and carbon dioxide contents of the smokes of 220 brands of foreign commercial cigarettes are reported. In some instances, filter cigarettes of certain brands were found to deliver as much or more smoke constituents than their nonfilter counterparts. Also, data indicated that there can be a great variation in the tar, nicotine, or carbon monoxide content of the smoke of samples of a given brand of cigarettes, depending on the nation in which they are purchased. 24 tables.
XPS study on the surface reaction of uranium metal with carbon monoxide at 200 degree C
International Nuclear Information System (INIS)
Wang Xiaoling; Fu Yibei; Xie Renshou; Huang Ruiliang
1996-12-01
The surface reaction of uranium metal with carbon monoxide at 200 degree C has been studied by X-ray photoelectron spectroscopy (XPS). The carbon monoxide adsorption on the surface oxide layer resulted in U4f peak shifting to the lower binding energy and the content of oxygen in the oxide is decreased. O/U radio decreases with increasing the exposure of carbon monoxide to the surface layer. The investigation indicated the surface layer of uranium metal was further reduced in the atmosphere of carbon monoxide at high temperature. (3 refs., 5 figs.)
Köthe, L; Radke, J
2010-06-01
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.
International Nuclear Information System (INIS)
Simpson, S.J.; Andersen, R.A.
1981-01-01
The thorium or uranium metallacycles [(Me 2 Si) 2 N] 2 MCH 2 Si(Me) 2 NSiMe 3 (I) react with tert-butyl cyanide to give the six-membered ring compounds [(Me 3 Si) 2 N] 2 MN = C(t-Bu)CH 2 Si(Me) 2 NSiMe 3 . The metallacycles (I) also react with the isoelectronic molecules tert-butyl isocyanide and carbon monoxide to give the unique five-membered ring compounds with exocyclic carbon-carbon double bonds, [(Me 3 Si) 2 N] 2 MXC(=CH 2 )Si(Me) 2 NSiMe 3 , where X is t-BuN or oxygen. The four-membered ring metallacycles (I) give simple coordination complexes of the type [(Me 3 Si) 2 N] 2 MCH 2 Si-(Me) 2 NSiMe 3 (N 3 SiMe 3 ) with trimethylsilyl azide
Kim, Hyo Jeong; Joe, Yeonsoo; Kim, Seul-Ki; Park, Se-Ung; Park, Jeongmin; Chen, Yingqing; Kim, Jin; Ryu, Jinhyun; Cho, Gyeong Jae; Surh, Young-Joon; Ryter, Stefan W; Kim, Uh-Hyun; Chung, Hun-Taeg
2017-09-01
Nonalcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome, has emerged as one of the most common causes of chronic liver disease in developed countries over the last decade. NAFLD comprises a spectrum of pathological hepatic changes, including steatosis, steatohepatitis, advanced fibrosis, and cirrhosis. Autophagy, a homeostatic process for protein and organelle turnover, is decreased in the liver during the development of NAFLD. Previously, we have shown that carbon monoxide (CO), a reaction product of heme oxygenase (HO) activity, can confer protection in NAFLD, though the molecular mechanisms remain unclear. We therefore investigated the mechanisms underlying the protective effect of CO on methionine/choline-deficient (MCD) diet-induced hepatic steatosis. We found that CO induced sestrin-2 (SESN2) expression through enhanced mitochondrial ROS production and protected against MCD-induced NAFLD progression through activation of autophagy. SESN2 expression was increased by CO or CO-releasing molecule (CORM2), in a manner dependent on signaling through the protein kinase R-like endoplasmic reticulum kinase (PERK), eukaryotic initiation factor-2 alpha (eIF2α)/ activating transcription factor-4 (ATF4)-dependent pathway. CO-induced SESN2 upregulation in hepatocytes contributed to autophagy induction through activation of 5'-AMP-activated protein kinase (AMPK) and inhibition of mechanistic target of rapamycin (mTOR) complex I (mTORC1). Furthermore, we demonstrate that CO significantly induced the expression of SESN2 and enhanced autophagy in the livers of MCD-fed mice or in MCD-media treated hepatocytes. Conversely, knockdown of SESN2 abrogated autophagy activation and mTOR inhibition in response to CO. We conclude that CO ameliorates hepatic steatosis through the autophagy pathway induced by SESN2 upregulation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Makoto Onodera
2016-01-01
Full Text Available Objective. This study examined the hypothesis that correlations exist between the carbon monoxide exposure time and the carboxyhemoglobin concentration at the site of carbon monoxide poisoning, using a pulse carbon monoxide oximeter in rural areas or the carboxyhemoglobin concentration measured at a given medical institution. Background. In previous studies, no definitive relationships between the arterial blood carboxyhemoglobin level and the severity of carbon monoxide poisoning have been observed. Method. The subjects included patients treated for acute carbon monoxide poisoning in whom a medical emergency team was able to measure the carboxyhemoglobin level at the site of poisoning. We examined the relationship between the carboxyhemoglobin level at the site of poisoning and carbon monoxide exposure time and the relationships between the arterial blood carboxyhemoglobin level and carbon monoxide exposure time. Results. A total of 10 patients met the above criteria. The carboxyhemoglobin levels at the site of poisoning were significantly and positively correlated with the exposure time (rs = 0.710, p=0.021, but the arterial blood carboxyhemoglobin levels were not correlated with the exposure time. Conclusion. In rural areas, the carboxyhemoglobin level measured at the site of carbon monoxide poisoning correlated with the exposure time.
Onodera, Makoto; Fujino, Yasuhisa; Kikuchi, Satoshi; Sato, Masayuki; Mori, Kiyofumi; Beppu, Takaaki; Inoue, Yoshihiro
2016-01-01
Objective. This study examined the hypothesis that correlations exist between the carbon monoxide exposure time and the carboxyhemoglobin concentration at the site of carbon monoxide poisoning, using a pulse carbon monoxide oximeter in rural areas or the carboxyhemoglobin concentration measured at a given medical institution. Background. In previous studies, no definitive relationships between the arterial blood carboxyhemoglobin level and the severity of carbon monoxide poisoning have been observed. Method. The subjects included patients treated for acute carbon monoxide poisoning in whom a medical emergency team was able to measure the carboxyhemoglobin level at the site of poisoning. We examined the relationship between the carboxyhemoglobin level at the site of poisoning and carbon monoxide exposure time and the relationships between the arterial blood carboxyhemoglobin level and carbon monoxide exposure time. Results. A total of 10 patients met the above criteria. The carboxyhemoglobin levels at the site of poisoning were significantly and positively correlated with the exposure time (rs = 0.710, p = 0.021), but the arterial blood carboxyhemoglobin levels were not correlated with the exposure time. Conclusion. In rural areas, the carboxyhemoglobin level measured at the site of carbon monoxide poisoning correlated with the exposure time.
Kent, Marc; Creevy, Kate E; Delahunta, Alexander
2010-01-01
Three adult Chihuahuas were presented for evaluation after smoke inhalation during a house fire. All three dogs received supportive care and supplemental oxygen. After initial improvement, the dogs developed seizures. Despite anticonvulsant therapy and supportive care, the dogs died. The brains of two dogs were examined. Lesions were identified that were compatible with acute carbon monoxide (CO) toxicity. Lesions were confined to the caudate nucleus, the globus pallidus, and the substantia nigra bilaterally, as well as the cerebellum, cerebral cortex, and dorsal thalamus. This case report describes the clinicopathological sequelae in acute CO toxicity.
Weng, Meng-Hsiung; Ju, Shin-Pon; Chen, Hsin-Tsung; Chen, Hui-Lung; Lu, Jian-Ming; Lin, Ken-Huang; Lin, Jenn-Sen; Hsieh, Jin-Yuan; Yang, Hsi-Wen
2013-02-01
The adsorption and dissociation properties of carbon monoxide (CO) molecule on tungsten W(n) (n = 10-15) nanoparticles have been investigated by density-functional theory (DFT) calculations. The lowest-energy structures for W(n) (n = 10-15) nanoparticles are found by the basin-hopping method and big-bang method with the modified tight-binding many-body potential. We calculated the corresponding adsorption energies, C-O bond lengths and dissociation barriers for adsorption of CO on nanoparticles. The electronic properties of CO on nanoparticles are studied by the analysis of density of state and charge density. The characteristic of CO on W(n) nanoparticles are also compared with that of W bulk.
Rana, Namrata; McLean, Samantha; Mann, Brian E; Poole, Robert K
2014-12-01
Carbon monoxide (CO) is a toxic gas that binds to haems, but also plays critical signalling and cytoprotective roles in mammalian systems; despite problems associated with systemic delivery by inhalation of the gas, it may be employed therapeutically. CO delivered to cells and tissues by CO-releasing molecules (CO-RMs) has beneficial and toxic effects not mimicked by CO gas; CO-RMs are also attractive candidates as novel antimicrobial agents. Salmonella enterica serovar Typhimurium is an enteropathogen causing gastroenteritis in humans. Recent studies have implicated haem oxygenase-1 (HO-1), the protein that catalyses the degradation of haem into biliverdin, free iron and CO, in the host immune response to Salmonella infection. In several studies, CO administration via CO-RMs elicited many of the protective roles of HO-1 induction and so we investigated the effects of a well-characterized water-soluble CO-RM, Ru(CO)3Cl(glycinate) (CORM-3), on Salmonella. CORM-3 exhibits toxic effects at concentrations significantly lower than those reported to cause toxicity to RAW 264.7 macrophages. We demonstrated here, through oxyhaemoglobin assays, that CORM-3 did not release CO spontaneously in phosphate buffer, buffered minimal medium or very rich medium. CORM-3 was, however, accumulated to high levels intracellularly (as shown by inductively coupled plasma MS) and released CO inside cells. Using growing Salmonella cultures without prior concentration, we showed for the first time that sensitive dual-beam integrating cavity absorption spectrophotometry can detect directly the CO released from CORM-3 binding in real-time to haems of the bacterial electron transport chain. The toxic effects of CO-RMs suggested potential applications as adjuvants to antibiotics in antimicrobial therapy. © 2014 The Authors.
Queiroga, Cláudia S F; Alves, Raquel M A; Conde, Sílvia V; Alves, Paula M; Vieira, Helena L A
2016-08-15
The neuroprotective role of carbon monoxide (CO) has been studied in a cell-autonomous mode. Herein, a new concept is disclosed - CO affects astrocyte-neuron communication in a paracrine manner to promote neuroprotection. Neuronal survival was assessed when co-cultured with astrocytes that had been pre-treated or not with CO. The CO-pre-treated astrocytes reduced neuronal cell death, and the cellular mechanisms were investigated, focusing on purinergic signaling. CO modulates astrocytic metabolism and extracellular ATP content in the co-culture medium. Moreover, several antagonists of P1 adenosine and P2 ATP receptors partially reverted CO-induced neuroprotection through astrocytes. Likewise, knocking down expression of the neuronal P1 adenosine receptor A2A-R (encoded by Adora2a) reverted the neuroprotective effects of CO-exposed astrocytes. The neuroprotection of CO-treated astrocytes also decreased following prevention of ATP or adenosine release from astrocytic cells and inhibition of extracellular ATP metabolism into adenosine. Finally, the neuronal downstream event involves TrkB (also known as NTRK2) receptors and BDNF. Pharmacological and genetic inhibition of TrkB receptors reverts neuroprotection triggered by CO-treated astrocytes. Furthermore, the neuronal ratio of BDNF to pro-BDNF increased in the presence of CO-treated astrocytes and decreased whenever A2A-R expression was silenced. In summary, CO prevents neuronal cell death in a paracrine manner by targeting astrocytic metabolism through purinergic signaling. © 2016. Published by The Company of Biologists Ltd.
DEFF Research Database (Denmark)
Dreyer-Andersen, Nanna; Almeida, Ana Sofia; Jensen, Pia
2018-01-01
cells constitute an alternative source of cells for transplantation in Parkinson's disease, but efficient protocols for controlled dopaminergic differentiation need to be developed. Short-term, low-level carbon monoxide (CO) exposure has been shown to affect signaling in several tissues, resulting...... in both protection and generation of reactive oxygen species. The present study investigated the effect of CO produced by a novel CO-releasing molecule on dopaminergic differentiation of human neural stem cells. Short-term exposure to 25 ppm CO at days 0 and 4 significantly increased the relative content...... of β-tubulin III-immunoreactive immature neurons and tyrosine hydroxylase expressing catecholaminergic neurons, as assessed 6 days after differentiation. Also the number of microtubule associated protein 2-positive mature neurons had increased significantly. Moreover, the content of apoptotic cells...
Modeling chemisorption kinetics of carbon monoxide on polycrystalline platinum
Energy Technology Data Exchange (ETDEWEB)
Donnelly, R.G.; Modell, M.; Baddour, R.F.
1978-04-01
Seven distinct desorption surface states of carbon monoxide on polycrystalline platinum were detected by deconvoluting temperature-programed desorption spectra of 4-100% carbon monoxide monolayer coverage. The adstates had fixed activation energies of desorption (22.5-32.6 kcal/mole) over the entire coverage range. Rates of formation and populations were derived. The chemisorption was modeled by a Hinshelwood-type expression which allowed for site creation and suggested that adsorbed molecules are sufficiently mobile during desorption heating to fill ordered states of minimum energy and that chemisorption into these states is noncompetitive and determined by the surface. Spectra, diagrams, graphs, tables, and 49 references.
Kim, Hyun-Jun; Chung, Yun Kyung; Kwak, Kyeong Min; Ahn, Se-Jin; Kim, Yong-Hyun; Ju, Young-Su; Kwon, Young-Jun; Kim, Eun-A
2015-01-01
Acute carbon monoxide poisoning has important clinical value because it can cause severe adverse cardiovascular effects and sudden death. Acute carbon monoxide poisoning due to charcoal is well reported worldwide, and increased use of charcoal in the restaurant industry raises concern for an increase in occupational health problems. We present a case of carbon monoxide poisoning induced cardiomyopathy in a 47-year-old restaurant worker. A male patient was brought to the emergency department to syncope and complained of left chest pain. Cardiac angiography and electrocardiography were performed to rule out acute ischemic heart disease, and cardiac markers were checked. After relief of the symptoms and stabilization of the cardiac markers, the patient was discharged without any complications. Electrocardiography was normal, but cardiac angiography showed up to a 40% midsegmental stenosis of the right coronary artery with thrombotic plaque. The level of cardiac markers was elevated at least 5 to 10 times higher than the normal value, and the carboxyhemoglobin concentration was 35% measured at one hour after syncope. Following the diagnosis of acute carbon monoxide poisoning induced cardiomyopathy, the patient's medical history and work exposure history were examined. He was found to have been exposed to burning charcoal constantly during his work hours. Severe exposure to carbon monoxide was evident in the patient because of high carboxyhemoglobin concentration and highly elevated cardiac enzymes. We concluded that this exposure led to subsequent cardiac injury. He was diagnosed with acute carbon monoxide poisoning-induced cardiomyopathy due to an unsafe working environment. According to the results, the risk of exposure to noxious chemicals such as carbon monoxide by workers in the food service industry is potentially high, and workers in this sector should be educated and monitored by the occupational health service to prevent adverse effects.
2012-09-07
... processes; CO 2 from fermentation during ethanol production or other industrial fermentation processes; CO 2... domestic alternative energy production, enhance forest management and create related employment... control, Carbon monoxide, Intergovernmental relations, Lead, Nitrogen dioxide, Ozone, Particulate matter...
Carbon Monoxide Hazards from Small Gasoline Powered Engines
... DHHS (NIOSH) Publication No. 96-118 (1996) Describes health effects and current standards and guidelines relating to carbon monoxide, as well as recommendations for workers, employers, and manufacturers regarding small gasoline powered engine ...
Energy Technology Data Exchange (ETDEWEB)
Etherton, B.P.
1980-01-01
The adsorption and desorption of hydrogen and carbon monoxide were studied on alumina-supported iridium catalysts which were examined by a scanning transmission electron microscope (STEM). The metal particle size and number of particles per area of catalyst increased with increasing metal loading. The particles were approx. 10 A. in diameter, cubo-octahedral shaped, and approx. 80-90% disperse. The STEM electron beam caused negligible damage to the samples. Hydrogen adsorption measurements showed that the hydrogen-iridium atom ratio was 1.2:1-1.3:1 and increased with decreasing metal loading. Temperature-programed desorption showed four types of adsorbed hydrogen desorbing at -90/sup 0/C (I), 15/sup 0/C (IV), 115/sup 0/C (II), and 245/sup 0/C (III). Types II and IV desorb from single atom sites and Types I and III from multiple atom sites. Type I is in rapid equilibrium with the gas phase. All desorption processes appear to be first order. Carbon monoxide adsorbed nondissociatively at 25/sup 0/C with approx. 0.7:1 CO/Ir atom ratio. It adsorbed primarily in linear forms at low coverage, but a bridged form appeared at high coverage.
Rossner, Alan; Jordan, Carolyn E; Wake, Cameron; Soto-Garcia, Lydia
2017-10-01
The interest in biomass fuel is continuing to expand globally and in the northeastern United States as wood pellets are becoming a primary source of fuel for residential and small commercial systems. Wood pellets for boilers are often stored in basement storage rooms or large bag-type containers. Due to the enclosed nature of these storage areas, the atmosphere may exhibit increased levels of carbon monoxide. Serious accidents in Europe have been reported over the last decade in which high concentrations of carbon monoxide (CO) have been found in or near bulk pellet storage containers. The aim of this study was to characterize the CO concentrations in areas with indoor storage of bulk wood pellets. Data was obtained over approximately 7 months (December 2013 to June 2014) at 25 sites in New Hampshire and Massachusetts: 16 homes using wood pellet boilers with indoor pellet storage containers greater than or equal to 3 ton capacity; 4 homes with wood pellet heating systems with outdoor pellet storage; 4 homes using other heating fuels; and a university laboratory site. CO monitors were set up in homes to collect concentrations of CO in the immediate vicinity of wood pellet storage containers, and data were then compared to those of homes using fossil fuel systems. The homes monitored in this study provided a diverse set of housing stock spanning two and a half centuries of construction, with homes built from 1774 to 2013, representing a range of air exchange rates. The CO concentration data from each home was averaged hourly and then compared to a threshold of 9 ppm. While concentrations of CO were generally low for the homes studied, the need to properly design storage locations for pellets is and will remain a necessary component of wood pellet heating systems to minimize the risk of CO exposure. This paper is an assessment of carbon monoxide (CO) exposure from bulk wood pellet storage in homes in New Hampshire and Massachusetts. Understanding the CO concentrations
Onodera, Makoto; Fujino, Yasuhisa; Kikuchi, Satoshi; Sato, Masayuki; Mori, Kiyofumi; Beppu, Takaaki; Inoue, Yoshihiro
2016-01-01
Objective. This study examined the hypothesis that correlations exist between the carbon monoxide exposure time and the carboxyhemoglobin concentration at the site of carbon monoxide poisoning, using a pulse carbon monoxide oximeter in rural areas or the carboxyhemoglobin concentration measured at a given medical institution. Background. In previous studies, no definitive relationships between the arterial blood carboxyhemoglobin level and the severity of carbon monoxide poisoning have been o...
International Nuclear Information System (INIS)
Zeisler, S.K.; Nader, M.; Theobald, A.; Oberdorfer, F.
1997-01-01
A new method for the efficient conversion of no-carrier-added [ 11 C]carbon dioxide into [ 11 C]carbon monoxide is described. [ 11 C]Carbon dioxide produced by proton bombardment of ultra high purity nitrogen is pre-concentrated in a cryo trap and then passed through a quartz tube filled with a mesh of thin molybdenum wire heated to 850 o C. [ 11 C]Carbon dioxide readily reacts with molybdenum to form [ 11 C]carbon monoxide and molybdenum(IV) oxide. The latter also reduces carbon dioxide to carbon monoxide and helps improve the performance of the converter. [ 11 C]Carbon monoxide is purified from remaining [ 11 C]carbon dioxide and collected in a small silica trap from which it is eluted into a reaction mixture for the palladium-mediated synthesis of a 11 C-labelled aromatic ketone. Radiochemical yields of up to 81% (decay-corrected) for [ 11 C]carbon monoxide were obtained. Radiochemical purity and specific radioactivity of both [ 11 C]carbon monoxide and the 11 C-labelled ketone are sufficient for nuclear medical studies with PET. (Author)
Carbon monoxide poisoning and death in a large enclosed ventilated area.
Huston, Butch; Froloff, Victor; Mills, Kelly; McGee, Michael
2013-11-01
A 55-year-old man with a medical history of tobacco use suddenly collapsed while power washing an empty indoor pool in a hotel. The decedent was transported to the local hospital where he was pronounced. A postmortem examination revealed atherosclerotic heart disease and bilateral pulmonary edema and congestion. A postmortem blood carbon monoxide (CO) level was 27% saturation, and a CO performed on hospital admission blood was 49% saturation. CO poisoning is a common cause of toxicological morbidity and mortality in the United States. The circumstances most often occur in an enclosed environment and may be intentional or unintentional. CO poisoning has been reported in open, well-ventilated spaces, but rarely results in death. A warning label was present on the engine clearly stating the dangers of CO emission. However, there was a false sense of security due to the large size of the pool room and the presence of industrial blowers that were being used for ventilation. © 2013 American Academy of Forensic Sciences.
Carbon monoxide releasing molecule-2 ameliorates IL-1β-induced IL-8 in human gastric cancer cells
International Nuclear Information System (INIS)
Lian, Sen; Xia, Yong; Ung, Trong Thuan; Khoi, Pham Ngoc; Yoon, Hyun Joong; Kim, Nam Ho; Kim, Kyung Keun; Jung, Young Do
2016-01-01
Carbon monoxide (CO), a byproduct of heme oxygenase (HO), presents antioxidant, anti-inflammatory, and anti-tumor properties. Accumulating evidence supports that interleukin (IL)-8 contribute to the vascularity of human gastric cancer. However, the inhibition of IL-8 expression by CO is yet to be elucidated. Here, we utilized CO releasing molecule-2 (CORM-2) to investigate the effect of CO on IL-1β-induced IL-8 expression and the underlying molecular mechanisms in human gastric cancer AGS cells. CORM-2 dose-dependently suppressed IL-1β-induced IL-8 mRNA and protein expression as well as IL-8 promoter activity. IL-1β induced the translocation of p47 phox to activate reactive oxygen species (ROS)-producing NADPH oxidase (NOX). Moreover, IL-1β activated MAPKs (Erk1/2, JNK1/2, and p38 MAPK) and promoted nuclear factor (NF)-kB and activator protein (AP)-1 binding activities. Pharmacological inhibition and mutagenesis studies indicated that NOX, ROS, Erk1/2, and p38 MAPK are involved in IL-1β-induced IL-8 expression. Transient transfection of deletion mutant constructs of the IL-8 promoter in cells suggested that NF-kB and AP-1 are critical for IL-1β-induced IL-8 transcription. NOX-derived ROS and MAPKs (Erk1/2 and p38 MAPK) functioned as upstream activators of NF-κB and AP-1, respectively. CORM-2 pretreatment significantly mitigated IL-1β-induced activation of ROS/NF-kB and Erk1/2/AP-1 cascades, blocking IL-8 expression and thus significantly reducing endothelial cell proliferation in the tumor microenvironment.
The electric dipole moment of cobalt monoxide, CoO
Energy Technology Data Exchange (ETDEWEB)
Zhuang, Xiujuan, E-mail: zhuangxj@hnu.edu.cn [College of Physics and Microelectronics Science, Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China); Steimle, Timothy C. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States)
2014-03-28
A number of low-rotational lines of the E{sup 4}Δ{sub 7/2} ← X{sup 4}Δ{sub 7/2} (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h{sub 7/2}, and the electron quadrupole parameter, eQq{sub 0}, for the E{sup 4}Δ{sub 7/2}(υ = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, μ{sup -vector}{sub el}, for the X{sup 4}Δ{sub 7/2} (υ = 0) and E{sup 4}Δ{sub 7/2} (υ = 1) states were determined to be 4.18 ± 0.05 D and 3.28 ± 0.05 D, respectively, from the analysis of the observed Stark spectra of F′ = 7 ← F″ = 6 branch feature in the Q(7/2) line and the F′ = 8 ← F″ = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed.
Pierik, A.J.; Roseboom, W.; Happe, R.P.; Bagley, K.A.; Albracht, S.P.J.
1999-01-01
Infrared-spectroscopic studies on the [NiFe]-hydrogenase of Chromatium vinosum-enriched in 15N or 13C, as well as chemical analyses, show that this enzyme contains three non-exchangeable, intrinsic, diatomic molecules as ligands to the active site, one carbon monoxide molecule and two cyanide
DEFF Research Database (Denmark)
Lawson-Smith, Pia; Jansen, Erik C; Hilsted, Linda
2010-01-01
Hydrogen cyanide (HCN) and carbon monoxide (CO) may be important components of smoke from fire accidents. Accordingly, patients admitted to hospital from fire accidents may have been exposed to both HCN and CO. Cyanide (CN) intoxication results in cytotoxic hypoxia leading to organ dysfunction...... and animal experiments have shown that in rats exposed to CN intoxication, HBO can increase the concentration of CN in whole blood....
Directory of Open Access Journals (Sweden)
Di Donato Michele
2009-12-01
Full Text Available Abstract Background High levels of exhaled carbon monoxide (eCO are a marker of airway or lung inflammation. We investigated whether hypo- or hyperventilation can affect measured values. Methods Ten healthy volunteers were trained to achieve sustained end-tidal CO2 (etCO2 concentrations of 30 (hyperventilation, 40 (normoventilation, and 50 mmHg (hypoventilation. As soon as target etCO2 values were achieved for 120 sec, exhaled breath was analyzed for eCO with a photoacoustic spectrometer. At etCO2 values of 30 and 40 mmHg exhaled breath was sampled both after a deep inspiration and after a normal one. All measurements were performed in two different environmental conditions: A ambient CO concentration = 0.8 ppm and B ambient CO concentration = 1.7 ppm. Results During normoventilation, eCO mean (standard deviation was 11.5 (0.8 ppm; it decreased to 10.3 (0.8 ppm during hyperventilation (p 2 changes (hyperventilation: 10% Vs 25% decrease; hypoventilation 3% Vs 25% increase. Taking a deep inspiration before breath sampling was associated with lower eCO values (p Conclusions eCO measurements should not be performed during marked acute hyperventilation, like that induced in this study, but the influence of less pronounced hyperventilation or of hypoventilation is probably negligible in clinical practice
Dong, De-Li; Chen, Chang; Huang, Wei; Chen, Yan; Zhang, Xiao-Lan; Li, Zhe; Li, Yue; Yang, Bao-Feng
2008-08-20
Tricarbonyldichlororuthenium (II) dimer (CORM2) has been developed as carbon monoxide (CO) donor. We found that CORM2 activated a type of specific current which was distinct from the big-conductance Ca(2+)-activated K(+) current activated by CO in human umbilical vein endothelial cells (HUVECs). So the aim of the present study was to characterize the CORM2-induced current and to access the relation with CO releasing. CORM2 (100 microM) activated a kind of bi-directional current in HUVECs when the ramp protocol (holding potential 0 mV, from -120 mV to +120 mV) was applied. The current was not blocked by apamin, TRAM-34 and iberiotoxin, the small, intermediate and big-conductance Ca(2+) -activated K(+) channel blockers, and it was not sensitive to the pipette solution chelated with EGTA. CORM2 still activated the current when the chloride in the pipette solution was substituted by equal mol gluconic acid. Substitution of the sodium in the bath with choline significantly reduced the current activated by CORM2. The current was regarded as the non-selective cation current. The current showed slightly inward rectifier property and was not sensitive to Gd(3+) (100 microM), La(3+) (10 microM) or 2-aminoethoxydiphenyl borate (100 microM). CO (10 microM), CORM3 (100, 200 microM) and RuCl(3) (100 microM) were used as controls and showed no effect of the current activation. In conclusion, CORM2 activated the non-selective cation current in HUVECs independently of its CO releasing.
Hearing Loss due to Carbon Monoxide Poisoning
DEFF Research Database (Denmark)
Mehrparvar, Amir Houshang; Davari, Mohammad Hossein; Mollasadeghi, Abolfazl
2013-01-01
Carbon monoxide poisoning is one of the rare causes of hearing loss which may cause reversible or irreversible, unilateral or bilateral hearing loss after acute or chronic exposure. In this report, we present a case of bilateral sensorineural hearing loss in a secondary smelting workshop worker a...
Contributions of distinct gold species to catalytic reactivity for carbon monoxide oxidation
Guo, Li-Wen; Du, Pei-Pei; Fu, Xin-Pu; Ma, Chao; Zeng, Jie; Si, Rui; Huang, Yu-Ying; Jia, Chun-Jiang; Zhang, Ya-Wen; Yan, Chun-Hua
2016-11-01
Small-size (carbon monoxide at room temperature, by the aid of in situ X-ray absorption fine structure analysis and in situ diffuse reflectance infrared Fourier transform spectroscopy. We find that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction.
Florido, E. A.; Dagaas, N. A. C.
2017-05-01
This study was aimed to determine the carbon monoxide (CO) gas sensing capability of zinc oxide (ZnO) film fabricated by successive ionic layer adsorption and reaction (SILAR) on glass substrate. Films consisting of a mixture of flower-like clusters of ZnO nanorods and nanowires were observed using scanning electron microscopy (SEM). Current-voltage characterization of the samples showed an average resistivity of 13.0 Ω-m. Carbon monoxide gas was synthesized by mixing the required amount of formic acid and excess sulfuric acid to produce CO gas concentrations of 100, 200, 300, 400, and 500 parts per million (ppm) v/v with five trials for each concentration. Two sets of data were obtained. One set consisted of the voltage response of the single film sensor while the other set were obtained from the double film sensor. The voltage response for the single film sensor and the double film sensor showed an average sensitivity of 0.0038 volts per ppm and 0.0024 volts per ppm, respectively. The concentration the single film can detect with a 2V output is 526 ppm while the double film sensor can detect up to 833 ppm with a 2V output. This shows that using the double film sensor is advantageous compared to single film sensor, because of its higher concentration range due to the larger surface area for the gas to interact. Moreover, the measured average resistance for the single film sensor was 10 MΩ while for the double film sensor the average resistance was 5 MΩ.
Carbon monoxide exposure enhances arrhythmia after cardiac stress: involvement of oxidative stress.
André, Lucas; Gouzi, Fares; Thireau, Jérôme; Meyer, Gregory; Boissiere, Julien; Delage, Martine; Abdellaoui, Aldja; Feillet-Coudray, Christine; Fouret, Gilles; Cristol, Jean-Paul; Lacampagne, Alain; Obert, Philippe; Reboul, Cyril; Fauconnier, Jérémy; Hayot, Maurice; Richard, Sylvain; Cazorla, Olivier
2011-11-01
Arrhythmias following cardiac stress are a key predictor of death in healthy population. Carbon monoxide (CO) is a ubiquitous pollutant promoting oxidative stress and associated with hospitalization for cardiovascular disease and cardiac mortality. We investigated the effect of chronic CO exposure on the occurrence of arrhythmic events after a cardiac stress test and the possible involvement of related oxidative stress. Wistar rats exposed chronically (4 weeks) to sustained urban CO pollution presented more arrhythmic events than controls during recovery after cardiac challenge with isoprenaline in vivo. Sudden death occurred in 22% of CO-exposed rats versus 0% for controls. Malondialdehyde (MDA), an end-product of lipid peroxidation, was increased in left ventricular tissue of CO-exposed rats. Cardiomyocytes isolated from CO-exposed rats showed higher reactive oxygen species (ROS) production (measured with MitoSox Red dye), higher diastolic Ca(2+) resulting from SR calcium leak and an higher occurrence of irregular Ca(2+) transients (measured with Indo-1) in comparison to control cells after a high pacing sequence. Acute treatment with a ROS scavenger (N-acetylcysteine, 20 mmol/L, 1 h) prevented this sequence of alterations and decreased the number of arrhythmic cells following high pacing. Chronic CO exposure promotes oxidative stress that alters Ca(2+) homeostasis (through RYR2 and SERCA defects) and thereby mediates the triggering of ventricular arrhythmia after cardiac stress that can lead to sudden death.
Carbon Monoxide Emission and Concentration Models for Chiang Mai Urban Area
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
An emission inventory containing emissions from traffic and other sources was complied. Based on the analysis, Carbon Monoxide (CO) emissions from traffic play a very important role in CO levels in Chiang Mai area. Analysis showed that CO emissions from traffic during rush hours contributed approximately 90% of total CO emissions. Regional Atmospheric Modeling System (RAMS) was applied to simulate wind fields and temperatures in the Chiang Mai area, and eight cases were selected to study annual variations in wind fields and temperatures. Model results can reflect major features of wind fields and diurnal variations in temperatures. For evaluating the model performance, model results were compared with observed wind speed, wind direction and temperature, which were monitored at a meteorological tower. Comparison showed that model results are in good agreement with observations, and the model captured many of the observed features. HYbrid Particle And Concentration Transport model (HYPACT) was used to simulate CO concentration in the Chiang Mai area. Model results generally agree well with observed CO concentrations at the air quality monitoring stations, and can explain observed CO diurnal variations.
CT and clinical patterns in suicidal carbon monoxide
Energy Technology Data Exchange (ETDEWEB)
Grobovschek, M.; Geretsegger, C.; Weinberger, R.; Fartacek, R.
1988-12-01
Cranial CT is important to exclude the presence of a mass in the cavum cranii in case of an unclear suicide attempt, particularly a traumatic mass. It can be helpful also in cases of carbon monoxide intoxications.
CO2 Capture by Carbon Aerogel–Potassium Carbonate Nanocomposites
Directory of Open Access Journals (Sweden)
Guang Yang
2016-01-01
Full Text Available Recently, various composites for reducing CO2 emissions have been extensively studied. Because of their high sorption capacity and low cost, alkali metal carbonates are recognized as a potential candidate to capture CO2 from flue gas under moist conditions. However, undesirable effects and characteristics such as high regeneration temperatures or the formation of byproducts lead to high energy costs associated with the desorption process and impede the application of these materials. In this study, we focused on the regeneration temperature of carbon aerogel–potassium carbonate (CA–KC nanocomposites, where KC nanocrystals were formed in the mesopores of the CAs. We observed that the nanopore size of the original CA plays an important role in decreasing the regeneration temperature and in enhancing the CO2 capture capacity. In particular, 7CA–KC, which was prepared from a CA with 7 nm pores, exhibited excellent performance, reducing the desorption temperature to 380 K and exhibiting a high CO2 capture capacity of 13.0 mmol/g-K2CO3, which is higher than the theoretical value for K2CO3 under moist conditions.
Bortner, M. H.; Alyea, F. N.; Grenda, R. N.; Liebling, G. R.; Levy, G. M.
1973-01-01
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 first overtone band of CO at 2.3 mu. That band has been found to be much more suitable than the stronger fundamental band at 4.6 mu. Calculations for both wavelengths are presented which illustrate the effects of atmospheric temperature profiles, inversion layers, ground temperature and emissivity, CO profile, reflectivity, and atmospheric pressure. The applicable radiative transfer theory on which these calculations are based is described together with the principles of the technique.
Photochemistry of Fe2(CO)8(Mu-CH2)
National Research Council Canada - National Science Library
Branan, Daniel
2000-01-01
...), and its deuterated analog. We have determined that it behaves similarly to other dimetallic carbonyls in that it eliminates carbon monoxide upon irradiation with high-intensity UV/Visible light to form distinct single and double CO-loss products...
Retrieval of tropospheric carbon monoxide for the MOPITT experiment
Pan, Liwen; Gille, John C.; Edwards, David P.; Bailey, Paul L.; Rodgers, Clive D.
1998-12-01
A retrieval method for deriving the tropospheric carbon monoxide (CO) profile and column amount under clear sky conditions has been developed for the Measurements of Pollution In The Troposphere (MOPITT) instrument, scheduled for launch in 1998 onboard the EOS-AM1 satellite. This paper presents a description of the method along with analyses of retrieval information content. These analyses characterize the forward measurement sensitivity, the contribution of a priori information, and the retrieval vertical resolution. Ensembles of tropospheric CO profiles were compiled both from aircraft in situ measurements and from chemical model results and were used in retrieval experiments to characterize the method and to study the sensitivity to different parameters. Linear error analyses were carried out in parallel with the ensemble experiments. Results of these experiments and analyses indicate that MOPITT CO column measurements will have better than 10% precision, and CO profile measurement will have approximately three pieces of independent information that will resolve 3-5 tropospheric layers to approximately 10% precision. These analyses are important for understanding MOPITT data, both for application of data in tropospheric chemistry studies and for comparison with in situ measurements.
Energy Technology Data Exchange (ETDEWEB)
Kimura, K; Rikitake, T; Hasegawa, S [Tsukuba Univ., Sakura, Ibaraki Japan; Matsumoto, T; Tateno, Y
1979-06-01
Carbon dioxide and carbon monoxide labelled with carbon-11 have been produced in the remotecontrolled system for a large scale production of short lived radioactive substance with cyclotron in National Institute of Radiological Sciences. The single breath measurement with /sup 11/CO/sub 2/ and /sup 11/CO, using inhalation system and a coincidence positron camera combined with an on-line computer system (TOSBAC 3400 Model 31) has been employed to evaluate regional pulmonary blood flow and diffusing capacity in three normal volunteers and seven patients with chronic obstructive pulmonary disease (COPD), old lung tuberculosis and benign tumor. Regional clearance rate constant (lambda) and distribution index (lambda i/lambda t) were calculated from monoexponential removal curves measured by external counting over the chest in supine position. This process was performed in a short period of breath-holding (10 - 20 sec.) after a single breath of these radioactive gases mixed with room air. These parameters were calculated for each lung fields divided into four zones (bilateral upper and lower lung region). In our method, the activity of the inspired mixture were 5 - 35 mCi/L and each value in lung fields, divided into four zones, can be measured with time interval for one second. While the clearance rate of /sup 11/CO/sub 2/ seemed to be mainly limited by pulmonary blood flow, it was considered that the rate of /sup 11/CO were limited by not only the diffusing capacity but also the perfusion in each lung fields. In normal subjects, the distribution of regional clearance rate was showed approximately even for /sup 11/CO/sub 2/ and /sup 11/CO. It was caused of the measurement in supine position. In contrast, the distribution of these parameter was showed uneven in patients with lung disease, particularly with COPD.
Nitric oxide and carbon monoxide diffusing capacity after a 1-h oxygen dive to 9 m of sea water
van Ooij, P. J. A. M.; van Hulst, R. A.; Houtkooper, A.; Sterk, P. J.
2014-01-01
To prevent extensive pulmonary lesions in submerged oxygen divers lung function like the forced vital capacity (FVC) or the diffusing capacity for carbon monoxide (DL,co) are used to monitor pulmonary oxygen toxicity (POT). As the diffusing capacity for nitric oxide (DL,no) measures more accurately
CT and clinical patterns in suicidal carbon monoxide
International Nuclear Information System (INIS)
Grobovschek, M.; Geretsegger, C.; Weinberger, R.; Fartacek, R.
1988-01-01
Cranial CT is important to exclude the presence of a mass in the cavum cranii in case of an unclear suicide attempt, particularly a traumatic mass. It can be helpful also in cases of carbon monoxide intoxications. (orig.) [de
Evaluation of exposure to carbon monoxide associated with passive smoking
International Nuclear Information System (INIS)
Jo, W.-K.; Oh, J.-W.; Dong, J.-I.
2004-01-01
The current study measured breath carbon monoxide (CO) concentrations prior to and at prescribed time intervals after exposure to passive smoking under controlled conditions, along with the air CO concentration in the exposure room during the exposure periods. The postexposure breath CO levels were 1.4-2.7 times higher than the background breath CO levels after 30 min of exposure, yet only slightly higher after 10 min of exposure, thereby confirming that exposure to CO from passive smoking causes a significant body burden of CO. The air CO concentration gradually increased during the burning of a cigarette(s), regardless of the exposure duration, whereas it slightly decreased after burning. However, the pattern of breath CO decay was similar for the two different types of exposure (during and after a cigarette(s)) in each subject. The decrease in the postexposure alveolar CO concentrations was slow even in the early phase of the decay curves, indicating a monocompartment uptake and elimination model for the human body. The half-lives (78-277 min) estimated in the present study were comparable to those reported in previous studies associated with CO exposure from active smoking or other activities. The current study also evaluated the CO exposure of visitors and workers at three different types of recreation facility (bars, Internet cafes, and billiard halls) typically associated with passive smoking. The results confirmed that passive smoking is the major contributor to the CO exposure of nonsmoking visitors in a recreation environment. In addition, workplace exposure to CO from passive smoking was found to be the most important contributor to the daily CO exposure of nonsmoking recreation workers
Garage carbon monoxide levels from sources commonly used in intentional poisoning.
Hampson, Neil B; Holm, James R; Courtney, Todd G
2017-01-01
The incidence of intentional carbon monoxide (CO) poisoning is believed to have declined due to strict federal CO emissions standards for motor vehicles and the uniform application of catalytic converters (CC). We sought to compare ambient CO levels produced by automobiles with and without catalytic converters in a residential garage, as well as from other CO sources commonly used for intentional poisoning. CO levels were measured inside a freestanding 73 m3 one-car garage. CO sources included a 1971 automobile without CC, 2003 automobile with CC, charcoal grill, electrical generator, lawn mower and leaf blower. After 20 minutes of operation, the CO level in the garage was 253 PPM for the car without a catalytic converter and 30 PPM for the car equipped withone. CO levels after operating or burning the other sources were: charcoal 200 PPM; generator >999 PPM; lawn mower 198 PPM; and leaf blower 580 PPM. While emissions controls on automobiles have reduced intentional CO poisonings, alternate sources may produce CO at levels of the same magnitude as vehicles manufactured prior to the use of catalytic converters. Those involved in the care of potentially suicidal individuals should be aware of this.
Kim, Ock-Joo; Park, Se Hong
2012-08-31
This paper deals with social history of carbon monoxide poisoning in Korea in 1960s. From the mid 1950s, Korean society began to use coal briquettes (Yeontan) for fuel for cooking and heating in the winter, especially in urban area. As the use of coal briquettes replaced fire woods which had been used as fuel in traditional Korean society for centuries, incidence and deaths from carbon monoxide poisoning increased dramatically during the 1960s. The coal briquettes were used to heat the living rooms through "Ondol" arrangement. The coal briquettes at the kitchen place make the heated air and smoke, which pass through the horizontal space under a stone floor of the room and escape through chimney at the opposite site of the kitchen. This Ondol system could make leakage of carbon monoxide easily and thereby kill people who sleep in the room. In the 1960s, carbon monoxide poisoning by briquettes gas was a serious health problem to kill more people than all of the infectious diseases. It was a unique and very serious health hazard in 1960s Korea. No other place in the world has experienced such a high mortality and incidence from the briquettes gas as in Korea. Employing newspaper articles and epidemiological papers, this paper analyzes how the Korean society experienced and perceived carbon monoxide poisoning (CO poisoning) in 1960s. It also follows how the perception changed over time and how the changes affected social responses to CO poisoning. In the early 1960s, the CO poisoning was perceived as an accident due to carelessness of the people who did not fix the leakages of the Ondol system or that of the people who built the Ondol improperly. Mostly CO poisoning was the casualty caused by carelessness and ignorance of the poor class. The prevention measure was mainly education which would enlighten the ignorant so that they care about CO poisoning and their lives. It was the victims who were to be blamed, for they caused the their poisoning with their own
Motterlini, Roberto; Sawle, Philip; Hammad, Jehad; Mann, Brian E; Johnson, Tony R; Green, Colin J; Foresti, Roberta
2013-02-01
Carbon monoxide-releasing molecules (CO-RMs) are a class of organometallo carbonyl complexes capable of delivering controlled quantities of CO gas to cells and tissues thus exerting a broad spectrum of pharmacological effects. Here we report on the chemical synthesis, CO releasing properties, cytotoxicity profile and pharmacological activities of four novel structurally related iron-allyl carbonyls. The major difference among the new CO-RMs tested was that three compounds (CORM-307, CORM-308 and CORM-314) were soluble in dimethylsulfoxide (DMSO), whereas a fourth one (CORM-319) was rendered water-soluble by reacting the iron-carbonyl with hydrogen tetrafluoroborate. We found that despite the fact all compounds liberated CO, CO-RMs soluble in DMSO caused a more pronounced toxic effect both in vascular and inflammatory cells as well as in isolated vessels. More specifically, iron carbonyls soluble in DMSO released CO with a fast kinetic and displayed a marked cytotoxic effect in smooth muscle cells and RAW 247.6 macrophages despite exerting a rapid and pronounced vasorelaxation ex vivo. In contrast, CORM-319 that is soluble in water and liberated CO with a slower rate, preserved smooth muscle cell viability, relaxed aortic tissue and exerted a significant anti-inflammatory effect in macrophages challenged with endotoxin. These data suggest that iron carbonyls can be used as scaffolds for the design and synthesis of pharmacologically active CO-RMs and indicate that increasing water solubility and controlling the rate of CO release are important parameters for limiting their potential toxic effects. Copyright © 2012 Elsevier Ltd. All rights reserved.
On Estimation of Contamination from Hydrogen Cyanide in Carbon Monoxide Line-intensity Mapping
Energy Technology Data Exchange (ETDEWEB)
Chung, Dongwoo T.; Li, Tony Y.; Viero, Marco P.; Church, Sarah E.; Wechsler, Risa H., E-mail: dongwooc@stanford.edu [Kavli Institute for Particle Astrophysics and Cosmology, Physics Department, Stanford University, Stanford, CA 94305 (United States)
2017-09-01
Line-intensity mapping surveys probe large-scale structure through spatial variations in molecular line emission from a population of unresolved cosmological sources. Future such surveys of carbon monoxide line emission, specifically the CO(1-0) line, face potential contamination from a disjointed population of sources emitting in a hydrogen cyanide emission line, HCN(1-0). This paper explores the potential range of the strength of HCN emission and its effect on the CO auto power spectrum, using simulations with an empirical model of the CO/HCN–halo connection. We find that effects on the observed CO power spectrum depend on modeling assumptions but are very small for our fiducial model, which is based on current understanding of the galaxy–halo connection. Given the fiducial model, we expect the bias in overall CO detection significance due to HCN to be less than 1%.
Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during ...
African Journals Online (AJOL)
Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo 2 ) and End Tidal Carbon Dioxide (EtCO 2 ) ... Respiratory adjustments were done for EtCO2 levels above 60mmHg or SPO2 below 92% or adverse haemodynamic changes.
Novelli, P. C.; Collins, J. E., Jr.; Myers, R. C.; Sachse, G. W.; Scheel, H. E.
1994-01-01
The carbon monoxide (CO) reference scale created by the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) is used to quantify measurements of CO in the atmosphere, calibrate standards of other laboratories and to otherwise provide reference gases to the community measuring atmospheric CO. This reference scale was created based upon a set of primary standards prepared by gravimetric methods at CMDL and has been propagated to a set of working standards. In this paper we compare CO mixing ratios assigned to the working standards by three approaches: (1) calibration against the original gravimetric standards, (2) calibration using only working standards as the reference gas, and (3) calibration against three new gravimetric standards prepared to CMDL. The agreement between these values was typically better than 1%. The calibration histories of CMDL working standards are reviewed with respect to expected rates of CO change in the atmosphere. Using a Monte Carlo approach to simulate the effect of drifting standards on calculated mixing ratios, we conclude that the error solely associated with the maintenance of standards will limit the ability to detect small CO changes in the atmosphere. We also report results of intercalibration experiments conducted between CMDL and the Diode Laser Sensor Group (DACOM) at the NASA Langley Research Center (Hampton, Virginia), and CMDL and the Fraunhofer-Institut (Garmisch-Partenkirchen, Germany). Each laboratory calibrated several working standards for CO using their reference gases, and these results were compared to calibrations conducted by CMDL. The intercomparison of eight standards (CO concentrations between approximately 100 and approximately 165 ppb) by CMDL and NASA agreed to better than +/- 2%. The calibration of six standards (CO concentrations between approximately 50 and approximately 210 ppb) by CMDL and the Fraunhofer-Institut agreed to within +/- 2% for four
Ozcan, Namik; Ozcam, Giray; Kosar, Pinar; Ozcan, Ayse; Basar, Hulya; Kaymak, Cetin
2016-01-01
Carbon monoxide is a toxic gas for humans and is still a silent killer in both developed and developing countries. The aim of this case series was to evaluate early radiological images as a predictor of subsequent neuropsychological sequelae, following carbon monoxide poisoning. After carbon monoxide exposure, early computed tomography scans and magnetic resonance imaging findings of a 52-year-old woman showed bilateral lesions in the globus pallidus. This patient was discharged and followed for 90 days. The patient recovered without any neurological sequela. In a 58-year-old woman exposed to carbon monoxide, computed tomography showed lesions in bilateral globus pallidus and periventricular white matter. Early magnetic resonance imaging revealed changes similar to that like in early tomography images. The patient recovered and was discharged from hospital. On the 27th day of exposure, the patient developed disorientation and memory impairment. Late magnetic resonance imaging showed diffuse hyperintensity in the cerebral white matter. White matter lesions which progress to demyelination and end up in neuropsychological sequelae cannot always be diagnosed by early computed tomography and magnetic resonance imaging in carbon monoxide poisoning. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.
Sun, Yutao; Zhou, Xiaocheng; Zheng, Guodong; Li, Jing; Shi, Hongyu; Guo, Zhengfu; Du, Jianguo
2017-11-01
Degassing of carbon monoxide (CO), which plays a significant role in the contribution of deep carbon to the atmosphere, commonly occurs within active fault zones. CO degassing from soil to the atmosphere in the Basin and Range province, west of Beijing (BRPB), China, was investigated by in-situ field measurements in the active fault zones. The measured concentrations of CO in soil gas in the BRPB ranged from 0.29 × 10-6 to 1.1 × 10-6 with a mean value of 0.6 × 10-6, which is approximately twice as large as that in the atmosphere. Net fluxes of CO degassing ranged from -48.6 mg m-2 d-1 to 12.03 mg m-2 d-1. The diffusion of CO from soil to the atmosphere in the BRPB was estimated to be at least 7.6 × 103 ton/a, which is comparable to the corresponding result of about 1.2 × 104 ton/a for CO2. CO concentrations were spatially heterogeneous with clearly higher concentrations along the NE-SW trending in the BRPB. These elevated values of CO concentrations were also coincident with the region with low-velocity and high conductivity in deep mantle, and high Poisson's ratio in the crust, thereby suggesting that CO degassing from the soil might be linked to upwelling of the asthenospheric mantle. Other sources of CO in the soil gas are suggested to be dominated by chemical reactions between deep fluids and carbonate minerals (e.g., dolomite, limestone, and siderite) in country rocks. Biogenic processes may also contribute to the CO in soil gas. The spatial distribution patterns of CO concentrations are coincident with the stress field, suggesting that the concentrations of CO could be a potential indicator for crustal stress field and, hence is potential useful for earthquake monitoring in the BRPB.
The neurotoxicology of carbon monoxide - Historical perspective and review.
Sykes, Oliver T; Walker, Edward
2016-01-01
Carbon monoxide (CO) has been recognized as a poison for centuries, and remains one of the most common causes of both accidental and deliberate poisoning worldwide. Despite this, there are widespread misconceptions with regards to the mechanisms, diagnosis and outcomes of CO induced poisoning such as the idea that CO poisoning is rare; that carboxyhaemoglobin levels above 20% and loss of consciousness are required before nervous system damage ensues; and that the binding of CO to haemoglobin is the only mechanism of toxicity. Prevention and diagnosis of CO poisoning is hampered by the lack of awareness of CO as a cause of illness, among both the general public and healthcare professionals. To complicate matters further there is no standardized definition of CO poisoning. Carboxyhaemoglobin levels are often used as a marker of CO poisoning, yet plasma levels rapidly reduce upon removal of the source and are therefore an unreliable biomarker of exposure and tissue damage. Adverse neuropsychiatric outcomes after CO poisoning are difficult to define, especially as they fluctuate, mimic other non-specific complaints, and are not present in all survivors. This paper challenges a number of misconceptions about CO poisoning which can result in misdiagnosis, and consequently in mismanagement. We illustrate how recent developments in the understanding of CO toxicology explain the particular susceptibility of the central nervous system to the effects of CO exposure. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
Salicio, Marcos Adriano; Mana, Viviane Aparecida Martins; Fett, Waléria Christiane Rezende; Gomes, Luciano Teixeira; Botelho, Clovis
2016-04-01
This article aims to analyze levels of exhaled carbon monoxide, carboxyhemoglobinand cardiopulmonary variables in old people practicing exercise in external environments, and correlate them with climate and pollution factors. Temporal ecological study with118 active elderly people in the city of Cuiabá, in the state of Mato Grosso, Brazil. Data were obtained on use of medication, smoking, anthropometric measurements, spirometry, peak flow, oxygen saturation, heart rate, exhaled carbon monoxide, carboxyhemoglobin, climate, number of farm fires and pollution. Correlations were found between on the one hand environmental temperature, relative humidity of the air and number of farmers' fires, and on the other hand levels of carbon monoxide exhaled and carboxyhemoglobin (p carboxyhemoglobin and heart rate. There is thus a need for these to be monitored during exercise. The use of a carbon monoxide monitor to evaluate exposure to pollutants is suggested.
Hrabovsky, Shari; Yingst, Jessica M; Veldheer, Susan; Hammett, Erin; Foulds, Jonathan
2017-06-01
Exhaled breath carbon monoxide (eBCO) reading is a useful tool for nurse practitioners to evaluate smoking status and other exposures to carbon monoxide (CO) to identify risk for cancer and chronic disease. This study aimed to measure one community's eBCO and identify potential environmental factors that may affect eBCO among nonsmokers. Data collected by convenience sampling at community health events included self-reported tobacco use and potential CO exposure. Means and frequency calculations describe the sample, two-sided t-tests determine differences in continuous variables, and chi-square tests determine differences in frequencies of CO levels between nontobacco users exposed to additional CO from their environment and nontobacco users who were not. As expected, smokers have significantly higher mean eBCO than nonsmokers (20.1 ppm vs. 4.4 ppm, p 6 ppm), although there were no environmental factors that explained a higher eBCO. Measuring eBCO provides an opportunity for the nurse practitioner to engage in a conversation about the impact of smoking and other environmental factors that contribute to eBCO and health. Keeping record of patients' smoking status and eBCO in their medical record is a valuable measure of the nurse practitioner's delivery of this care. ©2017 American Association of Nurse Practitioners.
Energy Technology Data Exchange (ETDEWEB)
Chung, Y.S. [Korea National Univ. of Education, Chongwon (Korea, Republic of); Tans, P.P.; Conway, T.J.; Dlugokencky, E.J. [Climate Monitoring and Diagnostics Lab., Bouler (United States); Novelli, P.C.; Tolier, M. [Colorado Univ. (United States). Cooperative Inst. for Research in Environmental Sciences; Wen, Y. [Chinese Academy of Meteorological Sciences, Beijing (China); Dagvadorj, D. [Mongolian Hydrometeorological Research Inst., Ulaan Batar (Mongolia)
1995-12-31
It has been discussed that the greenhouse gases, e.g. carbon dioxide (CO{sub 2}) methane (CH{sub 4}), enhance warming in the biosphere. Many scientists are therefore interested in monitoring the minor constituents of the atmosphere and in the carbon cycle. In cooperation with the Climate Monitoring and Diagnostics Laboratory (CMDL) of U.S. National Oceanic and Atmospheric Administration (NOAA), CO{sub 2}, CH{sub 4} and carbon monoxide (CO) at the western tip of the Tae-ahn Peninsula (TAP) in central Korea since October 1990 has been measured. Shortly thereafter, two more sites were added for the measurement of greenhouse gases in East Asia; one at Mount Waliguar Qinghai Province (QPC) in China and another at Ulaan Uul (UUM), the Gobi Desert in Mongolia. Also, trace gas data obtained at Mauna Loa (MLO) in Hawaii in the USA has been used. The Hawaiian data represent the world`s longest period of CO{sub 2} monitoring since 1958. The present monitoring is a part of the Global Air Sampling Network the WMO`s Global Atmospheric Watch. The method of collecting and measuring CO{sub 2}, CO and CH{sub 4} have been described else where. Here the four year monitoring of the trace gases at the three sites in East Asia is reported. The results are also compared with the measured values obtained at the free troposphere background site at MLO in Hawaii
Energy Technology Data Exchange (ETDEWEB)
Chung, Y S [Korea National Univ. of Education, Chongwon (Korea, Republic of); Tans, P P; Conway, T J; Dlugokencky, E J [Climate Monitoring and Diagnostics Lab., Bouler (United States); Novelli, P C; Tolier, M [Colorado Univ. (United States). Cooperative Inst. for Research in Environmental Sciences; Wen, Y [Chinese Academy of Meteorological Sciences, Beijing (China); Dagvadorj, D [Mongolian Hydrometeorological Research Inst., Ulaan Batar (Mongolia)
1996-12-31
It has been discussed that the greenhouse gases, e.g. carbon dioxide (CO{sub 2}) methane (CH{sub 4}), enhance warming in the biosphere. Many scientists are therefore interested in monitoring the minor constituents of the atmosphere and in the carbon cycle. In cooperation with the Climate Monitoring and Diagnostics Laboratory (CMDL) of U.S. National Oceanic and Atmospheric Administration (NOAA), CO{sub 2}, CH{sub 4} and carbon monoxide (CO) at the western tip of the Tae-ahn Peninsula (TAP) in central Korea since October 1990 has been measured. Shortly thereafter, two more sites were added for the measurement of greenhouse gases in East Asia; one at Mount Waliguar Qinghai Province (QPC) in China and another at Ulaan Uul (UUM), the Gobi Desert in Mongolia. Also, trace gas data obtained at Mauna Loa (MLO) in Hawaii in the USA has been used. The Hawaiian data represent the world`s longest period of CO{sub 2} monitoring since 1958. The present monitoring is a part of the Global Air Sampling Network the WMO`s Global Atmospheric Watch. The method of collecting and measuring CO{sub 2}, CO and CH{sub 4} have been described else where. Here the four year monitoring of the trace gases at the three sites in East Asia is reported. The results are also compared with the measured values obtained at the free troposphere background site at MLO in Hawaii
Energy Technology Data Exchange (ETDEWEB)
Ge, Jianbang; Wang, Shuai; Zhang, Feng; Zhang, Long; Jiao, Handong [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083 (China); Zhu, Hongmin [Department of Metallurgy, Materials Science, and Materials Processing, Tohoku University, Sendai 980-8579 (Japan); Jiao, Shuqiang, E-mail: sjiao@ustb.edu.cn [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083 (China)
2015-08-30
Highlights: • The electrodeposition of carbon films with a Mo{sub 2}C interlayer. • Carbon diffusion engenders the formation of Mo{sub 2}C interlayer. • The Mo{sub 2}C interlayer has a good adhesion. - Abstract: The electrodeposition of carbon films with a Mo{sub 2}C interlayer was investigated in LiCl-NaCl-Na{sub 2}CO{sub 3} melts at 900 °C. Cyclic voltammetry was applied to study the electrochemical reaction mechanism on Mo and Pt electrodes, indicating that, two reduction reactions including carbon deposition and carbon monoxide evolution, may take place on the two electrodes simultaneously during the cathodic sweep. Carbon films with a continuous Mo{sub 2}C interlayer were prepared by constant voltage electrolysis, showing a good adhesion between Mo substrate and carbon films. The carbon films with a Mo{sub 2}C interlayer were characterized using X-ray diffraction measurement, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The results reveal that carbon materials deposited on the electrodes are mainly composed of graphite and carbon diffusion in Mo (or Mo{sub 2}C) leads to the formation and growth of Mo{sub 2}C interlayer.
Energy Technology Data Exchange (ETDEWEB)
Novelli, P.C.; Collins, J.E. Jr.; Myers, R.C.; Sachse, G.W.; Scheel, H.E. [Univ. of Colordo, Boulder, CO (United States)]|[Science and Technology Corporation, Hampton, VA (United States)]|[NOAA, Boulder, CO (United States)]|[NASA, Langley Research Center, Hampton, VA (United States)]|[Fraunhofer-Inst. fuer Atmospharishce Umweltforschung (Germany)
1994-06-01
The carbon monoxide (CO) reference scale created by the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) is used to quantify measurements of CO in the atmosphere, calibrate standards of other laboratories and to otherwise provide reference gases to the community measuring atmospheric CO. This reference scale was created based upon a set of primary standards prepared by gravimetric methods at CMDL and has been propagated to a set of working standards. In this paper we compare CO mixing ratios assigned to the working standards by three approaches: (1) calibration against the original gravimetric standards, (2) calibration using only working standards as the reference gas, and (3) calibration against three new gravimetric standards prepared to CMDL. The agreement between these values was typically better than 1%. The calibration histories of CMDL working standards are reviewed with respect to expected rates of CO change in the atmosphere. Using a Monte Carlo approach to simulate the effect of drifting standards on calculated mixing ratios, we conclude that the error solely associated with the maintenance of standards will limit the ability to detect small CO changes in the atmosphere. We also report results of intercalibration experiments conducted between CMDL and the Diode Laser Sensor Group (DACOM) at the NASA Langley Research Center (Hampton, Virginia), and CMDL and the Fraunhofer-Institut (Garmisch-Partenkirchen, Germany). Each laboratory calibrated several working standards for CO using their reference gases, and these results were compared to calibrations conducted by CMDL. The intercomparison of eight standards (CO concentrations between approximately 100 and approximately 165 ppb) by CMDL and NASA agreed to better than +/- 2%. (Abstract Truncated)
Acute Carbon Monoxide Poisoning Resulting in ST Elevation Myocardial Infarction: A Rare Case Report
Directory of Open Access Journals (Sweden)
Po-Chao Hsu
2010-05-01
Full Text Available Acute carbon monoxide (CO poisoning with cardiac complications is well documented in the literature. However, ST segment elevation is a rare presentation, and most of these cases with ST elevation have revealed non-occlusive or normal coronary arteries. We report a case of CO poisoning complicated with ST elevation myocardial infarction. Emergency coronary angiography revealed total occlusion of the left anterior descending artery and primary percutaneous coronary intervention was performed. This report of a rare case should remind physicians that cardiovascular investigations, including electrocardiography, must be performed in cases with CO poisoning because mortality might increase if reperfusion therapy or appropriate medical treatments are not performed in patients with acute coronary artery occlusion.
DEFF Research Database (Denmark)
Lawson-Smith, Pia; Jansen, Erik C; Hilsted, Linda
2010-01-01
Hydrogen cyanide (HCN) and carbon monoxide (CO) may be important components of smoke from fire accidents. Accordingly, patients admitted to hospital from fire accidents may have been exposed to both HCN and CO. Cyanide (CN) intoxication results in cytotoxic hypoxia leading to organ dysfunction...... and possibly death. While several reports support the use of hyperbaric oxygen therapy (HBO) for the treatment of severe CO poisoning, limited data exist on the effect of HBO during CN poisoning. HBO increases the elimination rate of CO haemoglobin in proportion to the increased oxygen partial pressure...
Heme oxygenase and carbon monoxide protect from muscle dystrophy.
Chan, Mun Chun; Ziegler, Olivia; Liu, Laura; Rowe, Glenn C; Das, Saumya; Otterbein, Leo E; Arany, Zoltan
2016-11-28
Duchenne muscle dystrophy (DMD) is one of the most common lethal genetic diseases of children worldwide and is 100% fatal. Steroids, the only therapy currently available, are marred by poor efficacy and a high side-effect profile. New therapeutic approaches are urgently needed. Here, we leverage PGC-1α, a powerful transcriptional coactivator known to protect against dystrophy in the mdx murine model of DMD, to search for novel mechanisms of protection against dystrophy. We identify heme oxygenase-1 (HO-1) as a potential novel target for the treatment of DMD. Expression of HO-1 is blunted in the muscles from the mdx murine model of DMD, and further reduction of HO-1 by genetic haploinsufficiency worsens muscle damage in mdx mice. Conversely, induction of HO-1 pharmacologically protects against muscle damage. Mechanistically, HO-1 degrades heme into biliverdin, releasing in the process ferrous iron and carbon monoxide (CO). We show that exposure to a safe low dose of CO protects against muscle damage in mdx mice, as does pharmacological treatment with CO-releasing molecules. These data identify HO-1 and CO as novel therapeutic agents for the treatment of DMD. Safety profiles and clinical testing of inhaled CO already exist, underscoring the translational potential of these observations.
Carbon monoxide induces cardiac arrhythmia via induction of the late Na+ current.
Dallas, Mark L; Yang, Zhaokang; Boyle, John P; Boycott, Hannah E; Scragg, Jason L; Milligan, Carol J; Elies, Jacobo; Duke, Adrian; Thireau, Jérôme; Reboul, Cyril; Richard, Sylvain; Bernus, Olivier; Steele, Derek S; Peers, Chris
2012-10-01
Clinical reports describe life-threatening cardiac arrhythmias after environmental exposure to carbon monoxide (CO) or accidental CO poisoning. Numerous case studies describe disruption of repolarization and prolongation of the QT interval, yet the mechanisms underlying CO-induced arrhythmias are unknown. To understand the cellular basis of CO-induced arrhythmias and to identify an effective therapeutic approach. Patch-clamp electrophysiology and confocal Ca(2+) and nitric oxide (NO) imaging in isolated ventricular myocytes was performed together with protein S-nitrosylation to investigate the effects of CO at the cellular and molecular levels, whereas telemetry was used to investigate effects of CO on electrocardiogram recordings in vivo. CO increased the sustained (late) component of the inward Na(+) current, resulting in prolongation of the action potential and the associated intracellular Ca(2+) transient. In more than 50% of myocytes these changes progressed to early after-depolarization-like arrhythmias. CO elevated NO levels in myocytes and caused S-nitrosylation of the Na(+) channel, Na(v)1.5. All proarrhythmic effects of CO were abolished by the NO synthase inhibitor l-NAME, and reversed by ranolazine, an inhibitor of the late Na(+) current. Ranolazine also corrected QT variability and arrhythmias induced by CO in vivo, as monitored by telemetry. Our data indicate that the proarrhythmic effects of CO arise from activation of NO synthase, leading to NO-mediated nitrosylation of Na(V)1.5 and to induction of the late Na(+) current. We also show that the antianginal drug ranolazine can abolish CO-induced early after-depolarizations, highlighting a novel approach to the treatment of CO-induced arrhythmias.
International Nuclear Information System (INIS)
Chang, Kee Hyun; Suh, Chang Hae; Choo, In Wook
1986-01-01
Eleven magnetic resonance (MR) and computed tomographic (CT) imaging were performed in nine patients with mild to moderate degree of delayed neuropsychiatric symptoms following acute carbon monoxide (CO) poisoning, to evaluate the capability of MR in demonstrating any additional finding to CT. The MR images were obtained using 0.15 Tesla resistive system with various combination of three pulse sequences, including partial saturation recovery, T2-weighted spin echo and inversion recovery. Bilateral white matter abnormalities suggesting demyelination were demonstrated in 4 patients with MR and in only 2 patients with CT. The contrast discrimination between normal and abnormal white matter proved to be better with T2-weighted spin echo and inversion recovery than with partial saturation recovery and CT. But necrosis of the globus pallidus (1 patient) and diffuse atrophy (3 patients) were equally demonstrated on both MR and CT. It is suggested that MR be used as a initial imaging method in the evaluation of the delayed encephalopathy following acute CO poisoning, especially for the detection of the possible white matter lesions. Acute carbon monoxide (CO) poisoning produces hypoxia by displacing oxygen from hemoglobin and preventing its release from hemoglobin in tissues, often resulting in fetal event. Victims who survive acute CO poisoning may have various delayed symptoms and signs. Occasionally, an apparent recovery is followed within two days to three weeks by a sudden neurological deterioration. The degree of neuropsychiatric symptoms depends upon the extent and severity of the pathologic changes in the brain. The pathologic effects of CO poisoning are present in almost all organs of patients. However, the most important changes occur in the brain, which consist of necrosis of the globus pallidus and reticular zone of the substantia nigra, and the degeneration of the cerebral white matter. The diagnostic superiority of magnetic resonance (MR) over CT has already
Selection criteria utilized for hyperbaric oxygen treatment of carbon monoxide poisoning.
Hampson, N B; Dunford, R G; Kramer, C C; Norkool, D M
1995-01-01
Medical directors of North American hyperbaric oxygen (HBO) facilities were surveyed to assess selection criteria applied for treatment of acute carbon monoxide (CO) poisoning within the hyperbaric medicine community. Responses were received from 85% of the 208 facilities in the United States and Canada. Among responders, 89 monoplace and 58 multiplace chamber facilities treat acute CO poisoning, managing a total of 2,636 patients in 1992. A significant majority of facilities treat CO-exposed patients with coma (98%), transient loss of consciousness (LOC) (77%), ischemic changes on electrocardiogram (91%), focal neurologic deficits (94%), or abnormal psychometric testing (91%), regardless of carboxyhemoglobin (COHb) level. Although 92% would use HBO for a patient presenting with headache, nausea, and COHb 40%, only 62% of facilities utilize a specified minimum COHb level as the sole criterion for HBO therapy of an asymptomatic patient. When COHb is used as an independent criterion to determine HBO treatment, the level utilized varies widely between institutions. Half of responding facilities place limits on the delay to treatment for patients with only transient LOC. Time limits are applied less often in cases with persistent neurologic deficits. While variability exists, majority opinions can be derived for many patient selection criteria regarding the use of HBO in acute CO poisoning.
Carbon monoxide from neighbouring restaurants: the need for an integrated multi-agency response.
Keshishian, C; Sandle, H; Meltzer, M; Young, Y; Ward, R; Balasegaram, S
2012-12-01
Carbon monoxide (CO) is a colourless, odourless toxic gas produced during incomplete combustion of carbon-based fuels. Most CO incidents reported to the UK Health Protection Agency (HPA) are due to faulty gas appliances, and legislation exists to ensure gas appliances are properly installed. We present three CO poisoning incidents of unusual origin reported to the HPA. In each, residents living above restaurants were poisoned after workers left charcoal smouldering overnight in specialist or traditional ovens whilst ventilation systems were turned off. This led to production of CO, which travelled through floorboards and built up to dangerous concentrations in the flats. Working with local authorities, these incidents were investigated and resolved, and work was conducted to prevent further occurrences. The novel nature of these CO incidents led to delays in recognition and subsequent remedial action. Although previously undescribed, it is likely that due to the number of residences built above restaurants and the rising popularity of traditional cooking methods, similar incidents may be occurring and could increase in frequency. Multi-agency response and reporting mechanisms could be strengthened. Awareness raising in professional groups and the public on the importance of correct ventilation of such appliances is vital.
Sun, Wu; Kooijmans, Linda M. J.; Maseyk, Kadmiel; Chen, Huilin; Mammarella, Ivan; Vesala, Timo; Levula, Janne; Keskinen, Helmi; Seibt, Ulli
2018-02-01
Soil is a major contributor to the biosphere-atmosphere exchange of carbonyl sulfide (COS) and carbon monoxide (CO). COS is a tracer with which to quantify terrestrial photosynthesis based on the coupled leaf uptake of COS and CO2, but such use requires separating soil COS flux, which is unrelated to photosynthesis, from ecosystem COS uptake. For CO, soil is a significant natural sink that influences the tropospheric CO budget. In the boreal forest, magnitudes and variabilities of soil COS and CO fluxes remain poorly understood. We measured hourly soil fluxes of COS, CO, and CO2 over the 2015 late growing season (July to November) in a Scots pine forest in Hyytiälä, Finland. The soil acted as a net sink of COS and CO, with average uptake rates around 3 pmol m-2 s-1 for COS and 1 nmol m-2 s-1 for CO. Soil respiration showed seasonal dynamics controlled by soil temperature, peaking at around 4 µmol m-2 s-1 in late August and September and dropping to 1-2 µmol m-2 s-1 in October. In contrast, seasonal variations of COS and CO fluxes were weak and mainly driven by soil moisture changes through diffusion limitation. COS and CO fluxes did not appear to respond to temperature variation, although they both correlated well with soil respiration in specific temperature bins. However, COS : CO2 and CO : CO2 flux ratios increased with temperature, suggesting possible shifts in active COS- and CO-consuming microbial groups. Our results show that soil COS and CO fluxes do not have strong variations over the late growing season in this boreal forest and can be represented with the fluxes during the photosynthetically most active period. Well-characterized and relatively invariant soil COS fluxes strengthen the case for using COS as a photosynthetic tracer in boreal forests.
Response of Hepatoma 9618a and Normal Liver to Host Carbogen and Carbon Monoxide Breathing
Directory of Open Access Journals (Sweden)
Simon P. Robinson
1999-12-01
Full Text Available The effects of hyperoxia (induced by host carbogen 95% oxygen/5% carbon dioxide breathing. and hypoxia (induced by host carbon monoxide CO at 660 ppm. breathing were compared by using noninvasive magnetic resonance (MR methods to gain simultaneous information on blood flow/oxygenation and the bioenergetic status of rat Morris H9618a hepatomas. Both carbogen and CO breathing induced a 1.5- to 2-fold increase in signal intensity in blood oxygenation level dependent (BOLD MR images. This was due to a decrease in deoxyhemoglobin (deoxyHb, which acts as an endogenous contrast agent, caused either by formation of oxyhemoglobin in the case of carbogen breathing, or carboxyhemoglobin with CO breathing. The results were confirmed by observation of similar changes in deoxyHb in arterial blood samples examined ex vivo after carbogen or CO breathing. There was no change in nucleoside triphosphates (NTP/PI in either tumor or liver after CO breathing, whereas NTP/Pl increased twofold in the hepatoma (but not in the liver after carbogen breathing. No changes in tumor intracellular pH were seen after either treatment, whereas extracellular pH became more alkaline after CO breathing and more acid after carbogen breathing, respectively. This tumor type and the liver are unaffected by CO breathing at 660 ppm, which implies an adequate oxygen supply.
Pulido, Angeles; Nachtigall, Petr; Rodríguez Delgado, Montserrat; Otero Areán, Carlos
2009-05-11
Carbon monoxide adsorption on LTA (Linde type 5A) zeolite Ca-A is studied by using a combination of variable-temperature infrared spectroscopy and computational methods involving periodic density functional calculations and the correlation between stretching frequency and bond length of adsorbed CO species (nu(CO)/r(CO) correlation). Based on the agreement between calculated and experimental results, the main adsorption species can be identified as bridged Ca(2+)...CO...Ca(2+) complexes formed on dual-cation sites constituted by a pair of nearby Ca(2+) cations. Two types of such species can be formed: One of them has the two Ca(2+) ions located on six-membered rings of the zeolite framework and is characterized by a C-O stretching frequency in the range of 2174-2179 cm(-1) and an adsorption enthalpy of -31 to -33 kJ mol(-1), whereas the other bridged CO species is formed between a Ca(2+) ion located on an eight-membered ring and another one on a nearby six-membered ring and is characterized by nu(CO) in the range 2183-2188 cm(-1) and an adsorption enthalpy of -46 to -50 kJ mol(-1). Ca(2+)...CO monocarbonyl complexes are also identified, and at a relatively high CO equilibrium pressure, dicarbonyl species can also be formed.
Carbon Monoxide Epidemic Among Immigrant Populations: King County, Washington, 2006
Kwan-Gett, Tao; Hampson, Neil B.; Baer, Atar; Shusterman, Dennis; Shandro, Jamie R.; Duchin, Jeffrey S.
2009-01-01
Objectives. We investigated an outbreak of carbon monoxide (CO) poisoning after a power outage to determine its extent, identify risk factors, and develop prevention measures. Methods. We reviewed medical records and medical examiner reports of patients with CO poisoning or related symptoms during December 15 to 24, 2006. We grouped patients into households exposed concurrently to a single source of CO. Results. Among 259 patients with CO poisoning, 204 cases were laboratory confirmed, 37 were probable, 10 were suspected, and 8 were fatal. Of 86 households studied, 58% (n = 50) were immigrant households from Africa (n = 21), Asia (n = 15), Latin America (n = 10), and the Middle East (n = 4); 34% (n = 29) were US-born households. One percent of households was European (n = 1), and the origin for 7% (n = 6) was unknown. Charcoal was the most common fuel source used among immigrant households (82%), whereas liquid fuel was predominant among US-born households (34%). Conclusions. Educational campaigns to prevent CO poisoning should consider immigrants’ cultural practices and languages and specifically warn against burning charcoal indoors and incorrect ventilation of gasoline- or propane-powered electric generators. PMID:19608962
Rapid decline in carbon monoxide emissions and export from East Asia between years 2005 and 2016
Zheng, Bo; Chevallier, Frederic; Ciais, Philippe; Yin, Yi; Deeter, Merritt N.; Worden, Helen M.; Wang, Yilong; Zhang, Qiang; He, Kebin
2018-04-01
Measurements of Pollution in the Troposphere (MOPITT) satellite and ground-based carbon monoxide (CO) measurements both suggest a widespread downward trend in CO concentrations over East Asia during the period 2005–2016. This negative trend is inconsistent with global bottom-up inventories of CO emissions, which show a small increase or stable emissions in this region. We try to reconcile the observed CO trend with emission inventories using an atmospheric inversion of the MOPITT CO data that estimates emissions from primary sources, secondary production, and chemical sinks of CO. The atmospheric inversion indicates a ~ ‑2% yr‑1 decrease in emissions from primary sources in East Asia from 2005–2016. The decreasing emissions are mainly caused by source reductions in China. The regional MEIC inventory for China is the only bottom up estimate consistent with the inversion-diagnosed decrease of CO emissions. According to the MEIC data, decreasing CO emissions from four main sectors (iron and steel industries, residential sources, gasoline-powered vehicles, and construction materials industries) in China explain 76% of the inversion-based trend of East Asian CO emissions. This result suggests that global inventories underestimate the recent decrease of CO emission factors in China which occurred despite increasing consumption of carbon-based fuels, and is driven by rapid technological changes with improved combustion efficiency and emission control measures.
Exhaled carbon monoxide in asthmatics: a meta-analysis
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Huang Mao
2010-04-01
Full Text Available Abstract Background The non-invasive assessment of airway inflammation is potentially advantageous in asthma management. Exhaled carbon monoxide (eCO measurement is cheap and has been proposed to reflect airway inflammation and oxidative stress but current data are conflicting. The purpose of this meta-analysis is to determine whether eCO is elevated in asthmatics, is regulated by steroid treatment and reflects disease severity and control. Methods A systematic search for English language articles published between 1997 and 2009 was performed using Medline, Embase and Cochrane databases. Observational studies comparing eCO in non-smoking asthmatics and healthy subjects or asthmatics before and after steroid treatment were included. Data were independently extracted by two investigators and analyzed to generate weighted mean differences using either a fixed or random effects meta-analysis depending upon the degree of heterogeneity. Results 18 studies were included in the meta-analysis. The eCO level was significantly higher in asthmatics as compared to healthy subjects and in intermittent asthma as compared to persistent asthma. However, eCO could not distinguish between steroid-treated asthmatics and steroid-free patients nor separate controlled and partly-controlled asthma from uncontrolled asthma in cross-sectional studies. In contrast, eCO was significantly reduced following a course of corticosteroid treatment. Conclusions eCO is elevated in asthmatics but levels only partially reflect disease severity and control. eCO might be a potentially useful non-invasive biomarker of airway inflammation and oxidative stress in nonsmoking asthmatics.
Ni–Fe–S Cubanes in CO2 Reduction Electrocatalysis
DEFF Research Database (Denmark)
Varley, J. B.; Hansen, H. A.; Ammitzbøll, Nadia Luciw
2013-01-01
In this work, we perform extensive mechanistic studies of CO2 (electro)reduction by analogs to the active sites of carbon monoxide dehydrogenase (CODH) enzymes. We explore structure–property relationships for different cluster compositions and interpret the results with a model for CO2...... electroreduction we recently developed and applied to transition metal catalysts. Our results validate the effectiveness of the CODH in catalyzing this important reaction and give insight into why specific cluster compositions were adopted by nature....
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Makoto Sawano
2016-01-01
Full Text Available Numerous studies have confirmed the role of endogenous carbon monoxide (CO gas as a signal transmitter. However, CO is considered an intracellular transmitter, as no studies have demonstrated the redistribution of CO from the blood to tissue cells. Tracer analyses of 13 CO 2 production following 13 CO gas inhalation demonstrated that CO is oxidized to carbon dioxide (CO 2 in the body and that CO oxidation does not occur in the circulation. However, these results could not clearly demonstrate the redistribution of CO, because oxidation may have occurred in the airway epithelium. The objective of this study, therefore, was to definitively demonstrate and quantify the redistribution and oxidation of CO using time-course analyses of CO and 13 CO 2 production following 13 CO-hemoglobin infusion. The subject was infused with 0.45 L of 13 CO-saturated autologous blood. Exhaled gas was collected intermittently for 36 hours for measurement of minute volumes of CO/CO 2 exhalation and determination of the 13 CO 2 / 12 CO 2 ratio. 13 CO 2 production significantly increased from 3 to 28 hours, peaking at 8 hours. Of the infused CO, 81% was exhaled as CO and 2.6% as 13 CO 2 . Identical time courses of 13 CO 2 production following 13 CO-hemoglobin infusion and 13 CO inhalation refute the hypothesis that CO is oxidized in the airway epithelium and clearly demonstrate the redistribution of CO from the blood to the tissues. Quantitative analyses have revealed that 19% of CO in the circulating blood is redistributed to tissue cells, whereas 2.6% is oxidized there. Overall, these results suggest that CO functions as a systemic signal transmitter.
Production of Ethylene and Carbon Monoxide by Microorganisms
T. H. Filer; L. R. Brown; S. Brown-Sarobot; S. Martin
1984-01-01
Various quantities of ethylene and carbon monoxide were produced on PDA by Fusicladium effusum, Pestilotia nucicola, Alternaria tenuis, and Fusarium oxysporum subcultured from diseased pecan shucks. Repeated subculturing of these fungi on potato dextrose broth supplemented with iron powder produced ethylene. The production of...
Energy Technology Data Exchange (ETDEWEB)
Apfel, Holger
2012-10-10
In the present work the different power density of anode-supported high-temperature solid oxide fuel cells (ASC-SOFCs) were examined for carbon monoxide-containing fuels. In addition to wet hydrogen / carbon monoxide mixtures the cells were run with synthetic gas mixtures resembling the products of an autothermal reformer, and actual reformate generated by a 2 kW autothermal reformer. It was found that the power-voltage characteristics of an ASC depends primarily on the open circuit voltages of different gas mixtures, but is nearly independent of the hydrogen concentration of the fuel, although the reaction rates of other potential fuels within the gas mixture, namely carbon monoxide and methane, are much lower that the hydrogen reaction rate. The probable reason is that the main fuel for the electrochemical oxidation within the cell is hydrogen, while the nickel in the base layer of the anode acts as a reformer which replenishes the hydrogen by water reduction via carbon monoxide and methane oxidation.
Detection of the J = 6→5 transition of carbon monoxide
International Nuclear Information System (INIS)
Goldsmith, P.F.; Erickson, N.R.; Fetterman, H.R.; Clifton, B.J.; Peck, D.D.; Tannenwald, P.E.; Koepf, G.A.; Buhl, D.; McAvoy, N.
1981-01-01
The J = 6→5 rotational transition of carbon monoxide has been detected in emission from the KL ''plateau source'' in the Orion molecular cloud. The corrected peak antenna temperature is 100 K, and the FWHM line width is 26 km s -1 . These observations were carried out using the 3 m telescope of the NASA IRTF (Infrared Telescope Facility) on Mauna Kea, Hawaii, and constitute the first astronomical data obtained at submillimeter wavelengths with a heterodyne system using a laser local oscillator. Our data support the idea that the high-velocity dispersion CO in Orion is optically thin and set a lower limit to its temperature of approx.180 K
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Katarzyna Magierowska
2016-03-01
Full Text Available Carbon monoxide (CO produced by heme oxygenase (HO-1 and HO-2 or released from the CO-donor, tricarbonyldichlororuthenium (II dimer (CORM-2 causes vasodilation, with unknown efficacy against stress-induced gastric lesions. We studied whether pretreatment with CORM-2 (0.1–10 mg/kg oral gavage (i.g., RuCl3 (1 mg/kg i.g., zinc protoporphyrin IX (ZnPP (10 mg/kg intraperitoneally (i.p., hemin (1–10 mg/kg i.g. and CORM-2 (1 mg/kg i.g. combined with NG-nitro-l-arginine (l-NNA, 20 mg/kg i.p., 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 mg/kg i.p., indomethacin (5 mg/kg i.p., SC-560 (5 mg/kg i.g., and celecoxib (10 mg/kg i.g. affects gastric lesions following 3.5 h of water immersion and restraint stress (WRS. Gastric blood flow (GBF, the number of gastric lesions and gastric CO and nitric oxide (NO contents, blood carboxyhemoglobin (COHb level and the gastric expression of HO-1, HO-2, hypoxia inducible factor 1α (HIF-1α, tumor necrosis factor α (TNF-α, cyclooxygenase (COX-2 and inducible NO synthase (iNOS were determined. CORM-2 (1 mg/kg i.g. and hemin (10 mg/kg i.g. significantly decreased WRS lesions while increasing GBF, however, RuCl3 was ineffective. The impact of CORM-2 was reversed by ZnPP, ODQ, indomethacin, SC-560 and celecoxib, but not by l-NNA. CORM-2 decreased NO and increased HO-1 expression and CO and COHb content, downregulated HIF-1α, as well as WRS-elevated COX-2 and iNOS mRNAs. Gastroprotection by CORM-2 and HO depends upon CO’s hyperemic and anti-inflammatory properties, but is independent of NO.
Cobalt Oxide Nanosheet and CNT Micro Carbon Monoxide Sensor Integrated with Readout Circuit on Chip
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Ching-Liang Dai
2010-03-01
Full Text Available The study presents a micro carbon monoxide (CO sensor integrated with a readout circuit-on-a-chip manufactured by the commercial 0.35 μm complementary metal oxide semiconductor (CMOS process and a post-process. The sensing film of the sensor is a composite cobalt oxide nanosheet and carbon nanotube (CoOOH/CNT film that is prepared by a precipitation-oxidation method. The structure of the CO sensor is composed of a polysilicon resistor and a sensing film. The sensor, which is of a resistive type, changes its resistance when the sensing film adsorbs or desorbs CO gas. The readout circuit is used to convert the sensor resistance into the voltage output. The post-processing of the sensor includes etching the sacrificial layers and coating the sensing film. The advantages of the sensor include room temperature operation, short response/recovery times and easy post-processing. Experimental results show that the sensitivity of the CO sensor is about 0.19 mV/ppm, and the response and recovery times are 23 s and 34 s for 200 ppm CO, respectively.
Atmospheric observations of carbon monoxide and fossil fuel CO2 emissions from East Asia
DEFF Research Database (Denmark)
Turnbull, Jocelyn C.; Tans, Pieter P.; Lehman, Scott J.
2011-01-01
Flask samples from two sites in East Asia, Tae-Ahn Peninsula, Korea (TAP), and Shangdianzi, China (SDZ), were measured for trace gases including CO2, CO and fossil fuel CO2(CO(2)ff, derived from Delta(CO2)-C-14 observations). The five-year TAP record shows high CO(2)ff when local air comes from...... the Korean Peninsula. Most samples, however, reflect air masses from Northeastern China with lower CO(2)ff. Our small set of SDZ samples from winter 2009/2010 have strongly elevated CO(2)ff. Biospheric CO2 contributes substantially to total CO2 variability at both sites, even in winter when non-fossil CO2....../ppm respectively, consistent with recent bottom-up inventory estimates and other observational studies. Locally influenced TAP samples fall into two distinct data sets, ascribed to air sourced from South Korea and North Korea. The South Korea samples have low R-CO:CO2ff of 13 +/- 3 ppb/ppm, slightly higher than...
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M. Buchwitz
2007-01-01
Full Text Available Carbon monoxide (CO is an important atmospheric constituent affecting air quality and climate. SCIAMACHY on ENVISAT is currently the only satellite instrument that can measure the vertical column of CO with nearly equal sensitivity at all altitudes down to the Earth's surface because of its near-infrared nadir observations of reflected solar radiation. Here we present three years' (2003–2005 of SCIAMACHY CO columns consistently retrieved with the latest version of our retrieval algorithm (WFMDv0.6. We describe the retrieval method and discuss the multi-year global CO data set focusing on a comparison with the operational CO column data product of MOPITT. We found reasonable to good agreement (~20% with MOPITT, with the best agreement for 2004. We present detailed results for various regions (Europe, Middle East, India, China and discuss to what extent enhanced levels of CO can be detected over populated areas including individual cities. The expected CO signal from cities is close to or even below the detection limit of individual measurements. We show that cities can be identified when averaging long time series.
Drug-enhanced carbon monoxide production from heme by cytochrome P450 reductase
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Dragic Vukomanovic
2017-01-01
Full Text Available Carbon monoxide (CO formed endogenously is considered to be cytoprotective, and the vast majority of CO formation is attributed to the degradation of heme by heme oxygenases-1 and -2 (HO-1, HO-2. Previously, we observed that brain microsomes containing HO-2 produced many-fold more CO in the presence of menadione and its congeners; herein we explored these observations further. We determined the effects of various drugs on CO production of rat brain microsomes and recombinant human cytochrome P450 reductase (CPR; CO was measured by gas chromatography with reductive detection. Brain microsomes of Sprague-Dawley rats or recombinant human cytochrome P450 reductase (CPR were incubated with NADPH and various drugs in closed vials in phosphate buffer at pH 7.4 and 37°C. After 15 minutes, the reaction was stopped by cooling in dry ice, and the headspace gas was analyzed for CO production using gas chromatography with reductive (mercuric oxide detection. We observed drug-enhanced CO production in the presence of both microsomes and recombinant CPR alone; the presence of HO was not required. A range of structurally diverse drugs were capable of amplifying this CO formation; these molecules had structures consistent with redox cycling capability. The addition of catalase to a reaction mixture, that contained activating drugs, inhibited the production of CO. Drug-enhanced CO formation can be catalyzed by CPR. The mechanism of CPR activation was not through classical drug-receptor mediation. Redox cycling may be involved in the drug-induced amplification of CO production by CPR through the production of reactive oxygen species.
Global carbon monoxide as retrieved from SCIAMACHY by WFM-DOAS
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M. Buchwitz
2004-01-01
Full Text Available First results concerning the retrieval of tropospheric carbon monoxide (CO from satellite solar backscatter radiance measurements in the near-infrared spectral region (~2.3µm are presented. The Weighting Function Modified (WFM DOAS retrieval algorithm has been used to retrieve vertical columns of CO from SCIAMACHY/ENVISAT nadir spectra. We present detailed results for three days from the time periode January to October 2003 selected to have good overlap with the daytime CO measurements of MOPITT onboard EOS Terra. Because the WFM-DOAS Version 0.4 CO columns presented in this paper are scaled by a constant factor of 0.5 to compensate for an obvious overestimation we focus on the variability of the retrieved columns rather than on their absolute values. It is shown that plumes of CO resulting from, e.g. biomass burning in Africa, are detectable with single overpass SCIAMACHY data. Globally, the SCIAMACHY CO columns are in reasonable agreement with the Version 3 CO column data product of MOPITT. For example, for measurements over land, where the quality of the data is typically better than over ocean due to higher surface reflectivity, the standard deviation of the difference with respect to MOPITT is in the range 0.4-0.6x1018 molecules/cm2 and the linear correlation coefficient is between 0.4 and 0.7. The level of agreement between the data of both sensors depends on time and location but is typically within 30% for most latitudes. In the southern hemisphere outside Antarctica SCIAMACHY tends to give systematically higher values than MOPITT. More studies are needed to find out what the reasons for the observed differences with respect to MOPITT are and how the algorithm can be modified to improve the quality of the CO columns as retrieved from SCIAMACHY.
Sources of greenhouse gases and carbon monoxide in central London (UK)
Helfter, Carole; Tremper, Anja; Zazzeri, Giulia; Barlow, Janet F.; Nemitz, Eiko
2015-04-01
Biosphere-atmosphere exchange of carbon dioxide (CO2) has been on the scientific agenda for several decades and new technology now also allows for high-precision, continuous monitoring of fluxes of methane (CH4) and nitrous oxide (N2O). Compared to the natural environment, flux measurements in the urban environment, which is home to over 50% of the population globally, are still rare despite high densities of anthropogenic sources of pollutants. We report on over three years of measurements atop a 192 m tower in central London (UK), Europe's largest city, which started in October 2011. Fluxes of methane, carbon monoxide (CO) and carbon dioxide are measured by eddy-covariance (EC) at the British Telecom tower (51° 31' 17.4' N 0° 8' 20.04' W). In addition to the long-term measurements, EC fluxes of nitrous oxide (N2O) were measured in February 2014. All four trace gases exhibit diurnal trends consistent with anthropogenic activities with minimum emissions at night and early afternoon maxima. Segregating emissions by wind direction reveals heterogeneous source distributions with temporal patterns and source strengths that differ between compounds. The lowest emissions for CO, CO2 and CH4 were recorded for NW winds. The highest emissions of methane were in the SE sector, in the NE for CO2 and in the W for CO. Fluxes of all 3 gases exhibited marked seasonal trends characterised by a decrease in emissions in summer (63% reduction for CO, 36% for CO2 and 22% for CH4). Monthly fluxes of CO and CO2 were linearly correlated to air temperature (R2 = 0.7 and 0.59 respectively); a weaker dependence upon temperature was also observed for CH4 (R2 = 0.31). Diurnal and seasonal emissions of CO and CO2 are mainly controlled by local fossil fuel combustion and vehicle cold starts are thought to account for 20-30% of additional emissions of CO during the winter. Fugitive emissions of CH4 from the natural gas distribution network are thought to be substantial, which is consistent
Ionin, Andrey A.; Kozlov, Andrey Yu.; Seleznev, Leonid V.; Sinitsyn, Dmitry V.
2008-10-01
Overtone lasing and fundamental band tuning was for the first time obtained in a slab carbon monoxide laser. The compact slab CO laser with active volume 3×30×250 mm3 was excited by a repetitively pulsed capacitive RF discharge (81.36 MHz) with pulse repetition rate 100-500 Hz. The laser electrodes were cooled down to 120 K. Gas mixture CO:Air:He at gas pressures 15-22 Torr was used. An optical scheme "frequency selective master oscillator - laser amplifier" was applied for getting fundamental band tuning. Single line lasing with average power up to several tens of mW was observed on ~100 rotational-vibrational transitions of CO molecule within the spectral range ~5.0 - 6.5 micron. Multiline overtone lasing was observed on ~80 spectral lines within the spectral range ~2.5 -4.0 micron, with maximum single line average output power 12 mW. Total output power of the slab overtone CO laser came up to 0.3 W, with maximum laser efficiency 0.5%. Results of parametric studies of the overtone CO laser including complicated time behavior for laser pulses on different overtone vibrational-rotational transitions are discussed.
Luna, Bernadette; Somi, George; Winchester, J. Parker; Grose, Jeffrey; Mulloth, Lila; Perry, Jay L.
2013-01-01
Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. There is also concern about ambient ammonia levels in the absence of a condensing heat exchanger. In addition, new materials and formulations have become commercially available, formulations never evaluated by NASA for purposes of trace contaminant control. The optimal air revitalization system for future missions may incorporate a swing-bed system for carbon dioxide (CO2) and partial trace contaminant control, with a reduced-size, low-power, targeted trace contaminant system supplying the remaining contaminant removal capability. This paper describes the results of a comparative experimental investigation into materials for trace contaminant control that might be part of such a system. Ammonia sorbents and low temperature carbon monoxide (CO) oxidation catalysts are the foci. The data will be useful to designers of AR systems for future flexible path missions. This is a continuation of work presented in a prior year, with extended test results.
Carbon Monoxide (CO) Poisoning Prevention
... family by acting wisely in case of a power outage and learning the symptoms of CO poisoning. How to Recognize CO Poisoning The most common symptoms of CO poisoning are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion. People who are sleeping or who ...
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Akram Pourbakht
2011-06-01
Full Text Available Background and Aim: N-acetylcysteine, a glutathione precursor and reactive oxygen species scavenger, is reported to be effective in reducing noise-induced hearing loss. Many workers in industry are exposed simultaneously to noise and chemical pollutants such as carbon monoxide. We investigated effectiveness of N-acetylcysteine in protecting the cochlea from simultaneous noise and carbon monoxide damages.Methods: Twelve rabbits were exposed simeltaneously to 100 dB sound pressure level of broad band noise and carbon monoxide 8 hours a day for 5 days. One hour before exposure, experimental group received 325 mg/kg of N-acetylcysteine while normal saline was administered for the control group. The protective effect of N-acetylcysteine was evaluated 3 weeks after exposure by histological assessment of the hair cells.Results: Simultaneous exposure to noise and carbon monoxide resulted in a considerable damage to the outer hair cells; however, the inner hair cells and the pillar cells remained intact. Use of N-acetylcysteine in the experimental group significantly reduced the extent of outer hair cell loss.Conclusion: N-acetylcysteine attenuates simultaneous noise and carbon monoxide induced hair cell damage in rabbits.
Ocak, Tarik; Tekin, Erdal; Basturk, Mustafa; Duran, Arif; Serinken, Mustafa; Emet, Mucahit
2016-11-01
There is a lack of specificity of the analgesic agents used to treat headache and underlying acute carbon monoxide poisoning. To compare effectiveness of "oxygen alone" vs "metoclopramide plus oxygen" vs "metamizole plus oxygen" therapy in treating carbon monoxide-induced headache. A prospective, multicenter, double-blind, controlled trial. Three emergency departments in Turkey. Adult carbon monoxide poisoning patients with headache. A total of 117 carbon monoxide-intoxicated patients with headache were randomized into 3 groups and assessed at baseline, 30 minutes, 90 minutes, and 4 hours. The primary outcome was patient-reported improvement rates for headache. Secondary end points included nausea, need for rescue medication during treatment, and reduction in carboxyhemoglobin levels. During observation, there was no statistical difference between drug type and visual analog scale score change at 30 minutes, 90 minutes, or 4 hours, for either headache or nausea. No rescue medication was needed during the study period. The reduction in carboxyhemoglobin levels did not differ among the 3 groups. The use of "oxygen alone" is as efficacious as "oxygen plus metoclopramide" or "oxygen plus metamizole sodium" in the treatment of carbon monoxide-induced headache. Copyright © 2016 Elsevier Inc. All rights reserved.
Xiao, Yuanhua; Zhao, Xiaobing; Jin, Qingxian; Su, Dangcheng; Wang, Xuezhao; Wu, Shide; Zhou, Liming; Fang, Shaoming
2017-10-01
3D Hierarchical porous cobalt monoxide (CoO) nanoplates with a book-like structure derive from Co(CO3)0.5(OH)·0.11H2O by a two-steps oriented attachment mechanism in the solvothermal process. Firstly, nanoplates are formed by oriented attachment of nanorods. Secondly, new nanoplates could be generated on the old nanoplates by a sloped oriented attachment of nanorods with the based nanoplates shape into a 3D hierarchical book-like structure. The CoO nanoplates show superior specific capacitance about 1221.7 F g-1 at 1 A g-1 to most of the Co-based supercapacitor materials up to date. An asymmetric supercapacitor (ASC) based on positive electrode CoO and negative electrode active carbon (AC) exhibits an excellent energy density of 50.1 Wh kg-1 at a power density of 589 W kg-1 and gets a satisfactory cycling stability (86.3% of its initial capacitance retention at 10 A g-1 over 10 000 cycles).
Accidental Carbon Monoxide Poisonings in Adana, Turkey: A 14-year Study
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Murat Darçın
2017-03-01
Full Text Available Aim: Carbon monoxide (CO is often referred to as the “silent killer” because its victims cannot see it, smell it or taste it. CO is responsible for a large percentage of the accidental poisonings and deaths reported throughout the world. CO poisoning therefore is considered a serious global health threat. The aim of the present study was to describe the cases of CO poisoning in a rural areas of Adana, Turkey between 2002 and 2015 based on data collected from incident reports. Methods: The cases of accidental CO poisoning were statistically analyzed. During that period, 74 incidents occurred and 154 people were poisoned by accidental CO poisoning. Results: The results of this analysis indicate that men and adults aged ≥65 years were more likely to die from CO poisoning than others. The number of CO poisoning cases was highest during the heating season. The majority (72% of poisoning resulting in hospitalization with a life-threatening condition or death occurred within the home. Conclusion: CO poisoning is a serious danger. People must be informed about this hazard. By educating risk groups about the dangers of CO poisoning, it is possible to save many lives as well as reduce the health risks.
Ethylene and Carbon Monoxide Production by Septoria musiva
S. Brown-Skrobot; L. R. Brown; T. H. Filer
1984-01-01
An investigation into the mechanism by which Septoria musiva causes the premature defoliation of cottonwood trees was undertaken. Gas-chromatograpic analysis of the atmosphere overlying the original culture indicated that this fungus produced significant quantities of ethylene and carbon monoxide. Subcultures failed to produce either gas on a variety...
Composition of amino acid using carbon monoxide. Amide carbonylation reaction
Energy Technology Data Exchange (ETDEWEB)
Izawa, Kunisuke (Ajinomoto Co., Inc., Tokyo (Japan))
1989-02-01
Amide carbonylation reaction is a method to compose N-acyl-{alpha}-amino acid from aldehyde, carboxylic acid amide, and carbon monoxide in a phase and with high yield. Unlike the conventional Strecker reaction, this method does not use HCN which is in question on public pollution and does not require hydrolysis. This amide carbonylation reaction was discovered by Wakamatsu and others of Ajinomoto Co.,Ltd. Present application examples of this method are the composition of N-acetyl amino acid from the aldehyde class, the composition of N-Acyl amino acid from olefin, the composition of N-acyl or acetyl amino acid from the raw material of alcohol and the halide class, the composition of N-acyl or acetyl amino acid via the isomerization of epoxide and allyl alcohol, the composition of amino dicarboxylic acid, applying deoxidation of ring acid anhydride, the composition of N-acyl amino acid from the raw material of the amine class, the stereoselective composition of -substitution ring-{alpha}-amino acid, and the composition of amino aldehyde. 24 refs., 2 figs., 2 tabs.
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Zhang Weihui
2010-05-01
Full Text Available Abstract Background Hepatic ischemia-reperfusion injury (I/Ri is a serious complication occurring during liver surgery that may lead to liver failure. Hepatic I/Ri induces formation of reactive oxygen species, hepatocyte apoptosis, and release of pro-inflammatory cytokines, which together causes liver damage and organ dysfunction. A potential strategy to alleviate hepatic I/Ri is to exploit the potent anti-inflammatory and cytoprotective effects of carbon monoxide (CO by application of so-called CO-releasing molecules (CORMs. Here, we assessed whether CO released from CORM-2 protects against hepatic I/Ri in a rat model. Methods Forty male Wistar rats were randomly assigned into four groups (n = 10. Sham group underwent a sham operation and received saline. I/R group underwent hepatic I/R procedure by partial clamping of portal structures to the left and median lobes with a microvascular clip for 60 minutes, yielding ~70% hepatic ischemia and subsequently received saline. CORM-2 group underwent the same procedure and received 8 mg/kg of CORM-2 at time of reperfusion. iCORM-2 group underwent the same procedure and received iCORM-2 (8 mg/kg, which does not release CO. Therapeutic effects of CORM-2 on hepatic I/Ri was assessed by measuring serum damage markers AST and ALT, liver histology score, TUNEL-scoring of apoptotic cells, NFkB-activity in nuclear liver extracts, serum levels of pro-inflammatory cytokines TNF-α and IL-6, and hepatic neutrophil infiltration. Results A single systemic infusion with CORM-2 protected the liver from I/Ri as evidenced by a reduction in serum AST/ALT levels and an improved liver histology score. Treatment with CORM-2 also up-regulated expression of the anti-apoptotic protein Bcl-2, down-regulated caspase-3 activation, and significantly reduced the levels of apoptosis after I/Ri. Furthermore, treatment with CORM-2 significantly inhibited the activity of the pro-inflammatory transcription factor NF-κB as measured in
Interactions of carbon monoxide and hemoglobin at high altitude
Energy Technology Data Exchange (ETDEWEB)
Collier, C.R. (Univ. of Southern California Medical Center, Los Angeles); Goldsmith, J.R.
1983-01-01
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 condition 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.
Intra-pulse Cavity Enhanced Measurements of Carbon Monoxide in a Rapid Compression Machine
Nasir, Ehson Fawad; Farooq, Aamir
2018-01-01
A laser absorption sensor for carbon monoxide concentration was developed for combustion studies in a rapid compression machine using a pulsed quantum cascade laser near 4.89 μm. Cavity enhancement reduced minimum detection limit down to 2.4 ppm
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Hueso, J. L.; Martinez-Martinez, D.; Cabalerro, Alfonso; Gonzalez-Elipe, Agustin Rodriguez; Mun, Bongjin Simon; Salmeron, Miquel
2009-07-31
We have studied the oxidation of carbon monoxide over a lanthanum substituted perovskite (La0.5Sr0.5CoO3-d) catalyst prepared by spray pyrolysis. Under the assumption of a first-order kinetics mechanism for CO, it has been found that the activation energy barrier of the reaction changes from 80 to 40 kJ mol-1 at a threshold temperature of ca. 320 oC. In situ XPS near-ambient pressure ( 0.2 torr) shows that the gas phase oxygen concentration over the sample decreases sharply at ca. 300 oC. These two observations suggest that the oxidation of CO undergoes a change of mechanism at temperatures higher than 300 oC.
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Q. Guo
2017-09-01
Full Text Available East Asia is a densely populated region with a myriad of primary emissions of pollutants such as black carbon (BC and carbon monoxide (CO. To characterize primary emissions over the eastern coast of China, a series of field campaigns were conducted in 2011, including measurements from a ship cruise, island, and coastal receptor sites. The relationship between BC and CO is presented here for the first ship cruise (C1, the second ship cruise (C2, an island site (Changdao Island, CD, and a coastal site (Wenling, WL. The average BC mass concentrations were 2.43, 2.73, 1.09, 0.94, and 0.77 µg m−3 for CD, WL, C1-YS (Yellow Sea, C1-ES (East China Sea, and C2-ES, respectively. For those locations, the average CO mixing ratios were 0.55, 0.48, 0.31, 0.36, and 0.27 ppm. The high loadings of both BC and CO imply severe anthropogenic pollution over the eastern coast of China. Additionally, the linear correlation between BC and CO was regressed for each location. The slopes, i.e., the ratios of ΔBC to ΔCO derived from their relationship, correlated well with the ratios of diesel consumption to gasoline consumption in each province/city, which reveals vehicular emission to be the common source for BC and CO and that there are distinct fuel structures between North and South China. The ΔBC/ΔCO values at coastal sites (Changdao Island and Wenling were much higher than those over the Yellow Sea and East China Sea, and the correlation coefficients also showed a decreasing trend from the coast to the sea. Therefore, the quantity of ΔBC/ΔCO and the correlation coefficients are possible indicators for the aging and removal of BC.
Esquivel-Elizondo, Sofia; Maldonado, Juan; Krajmalnik-Brown, Rosa
2018-06-01
Carbon monoxide (CO)-metabolism and phenotypic and phylogenetic characterization of a novel anaerobic, mesophilic and hydrogenogenic carboxydotroph are reported. Strain SVCO-16 was isolated from anaerobic sludge and grows autotrophically and mixotrophically with CO. The genes cooS and cooF, coding for a CO dehydrogenase complex, and genes similar to hycE2, encoding a CO-induced hydrogenase, were present in its genome. The isolate produces H2 and CO2 from CO, and acetate and formate from organic substrates. Based on the 16S rRNA sequence, it is an Alphaproteobacterium most closely related to the genus Pleomorphomonas (98.9%-99.2% sequence identity). Comparison with other previously characterized Pleomorphomonas showed that P. diazotrophica and P. oryzae do not metabolize CO, and P. diazotrophica does not grow anaerobically with organic substrates. Average nucleotide identity values between strain SVCO-16 and P. diazotrophica, P. oryzae or P. koreensis were 86.66 ± 0.21%. These values are below the boundary to define species (95%-96%). Digital DNA-DNA hybridization estimates between strain SVCO-16 and reference strains were also below the 70% threshold for species delineation: 29.1%-34.5%. Based on the differences in CO metabolism, genome analyses and cellular fatty acid composition, the isolate should be classified into the genus Pleomorphomonas as a representative of a novel species, Pleomorphomonas carboxyditropha. The type strain of Pleomorphomonas carboxyditropha is SVCO-16T (strain deposit numbers, DSM 106132T and TSD-119T).
Gold, D; Geater, A; Aiyarak, S; Juengpraert, W
1999-07-01
Approximately 400 indigenous divers live and work on Thailand's west coast. They dive with surface supplied air from primitive compressor units mounted on open boats which measure from seven to 11 meters in length. It was suspected that carbon monoxide was present in the breathing air of at least the gasoline-driven compressor units. To determine the presence of carbon monoxide gas in the breathing air, compressed air from the compressor was pumped through the diver air supply hose through a plenum (monitoring) chamber established on the boat. After a compressor warm-up of 15 minutes, the diving air was measured with the boat at eight different bearings to the wind, each 45 degrees apart at intervals of five minutes. Three of the four gasoline-driven compressor units tested showed presence of carbon monoxide in the breathing air. One diesel-driven unit showed a very low concentration of carbon monoxide (3-4 ppm) and six diesel-driven units showed no detectable carbon monoxide. Although not tested, diesel exhaust emissions could also enter the breathing air by the same route. A locally made modification to the compressor air intake was designed and successfully tested on one gasoline-driven compressor unit. An information sheet on the hazards of carbon monoxide as well as on the modification has been developed for distribution among the villages.
Effects of continuous exposure to carbon monoxide on auditory vigilance in man
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Davies, D.M.; Jolly, E.J.; Pethybridge, R.J.; Colquhoun, W.P.
1981-02-01
Six different groups of non-smoking young male subjcts were stutied separately for 18 consecutive days each in a closed controlled-environment human exposure chamber. Each group was subjected to a 5-day control period in fresh air followed successively by an 8-day period of continuous exposure to 50 ppm, 15 ppm or 0 ppm (controll) by volume of carbon monoxide (CO) in air, and a 5-day recovery period in fresh air. The subjects performed a 1-h auditory vigilance task every day at the same time of day in a fixed qualitative, quantitative, and temporal relationship with food intake, consumption of stimulating beverages, physical activity, and sleep. It was concluded that such CO exposure, involving the continuous carriage of carboxyhaemoglobin loads up to 70%, was without significant effect on auditory vigilance.
CT of the brain in acute carbon monoxide poisoning
International Nuclear Information System (INIS)
Ohno, Masato; Uchino, Akira; Hayashi, Kazuji; Nakata, Hajime.
1988-01-01
Cerebral computed tomographic (CT) findings of acute carbon monoxide (Co) poisoning were analized in thirty-six cases treated with hyperbraric oxygen therapy and their relationship with prognosis was evaluated. The cases were classified into there groups, early stage, interval form, and non-interval form groups. In all groups, the initial abnormality was low density areas presumably due to edema, demyelination and/or softening. It was seen in the globus pallidus and/or white matter. Following these initial changes, cerebral hemorrhage, ventricular dilatation, and cerebral atrophy developed in a few cases. The frequency of abnormal CT findings was higher in the interval form group (85 %) or non-interval group (83 %) than the early stage group (41 %). The prognosis was good in most cases with normal CT findings. The possibility of recovery diminished in the patients with abnormal CT findings. The prognosis was particularly poor in cases showing abnormality both in globus pallidus and white matter. We conclude that CT is useful not only for detecting the pathologic change but also for predicting the prognosis of the patient with acute Co poisoning. (author)
International Nuclear Information System (INIS)
Acimis, N.M.; Bostanci, M.; Ergin, A.; Bozkurt, A.Y.; Ozsahin, A.
2009-01-01
To assess the prevalence of smoking and the effects of passive smoking among bank employees. This cross-sectional study was conducted between 2001 and 2002. Data was collected through questionnaire. The level of Carbon Monoxide (CO) and the percentage of Carboxihemoglobin (COHb) level in the blood were measured by using Bend fond Pico Smokerlyser. Chi-square and ANOVA were used. Six hundred fifty four respondents participated in the study which included 384 (58.7%) male and 267 (40.6%) female. The mean value for CO in the expiration air was 14.57+-11.1 ppm [(18.49 +- 11.21, 7.74 +- 5.71 and 4.85 +- 2.35; for current smokers, non-smokers with current exposure and non-smokers without current exposure, respectively (p<0.001)]. The mean value for COHb % was 2.97 +- 1.9 [(3.60 +- 1.88, 1.80 +- 1.17 and 1.21 +- 0.99; for current smokers, non-smokers with current exposure and non-smokers without current exposure, respectively (p<0.001)]. Passive smoking is still a significant health problem in the work place. Anti-tobacco implementations should be carried out strictly in all work places. (author)
[Carbon monoxide poisoning by a heating system].
Dietz, Eric; Gehl, Axel; Friedrich, Peter; Kappus, Stefan; Petter, Franz; Maurer, Klaus; Püschel, Klaus
2016-01-01
A case of accidental carbon monoxide poisoning in several occupants of two neighboring residential buildings in Hamburg-Harburg (Germany) caused by a defective gas central heating system is described. Because of leaks in one of the residential buildings and the directly adjacent wall of the neighboring house, the gas could spread and accumulated in both residential buildings, which resulted in a highly dangerous situation. Exposure to the toxic gas caused mild to severe intoxication in 15 persons. Three victims died still at the site of the accident. Measures to protect the occupants were taken only with a great delay. As symptoms were unspecific, it was not realized that the various alarms given by persons involved in the accident were related to the same cause. In order to take appropriate measures in time it is indispensible to recognize, assess and check potential risks, which can be done by using carbon monoxide warning devices and performing immediate COHb measurements with special pulse oximeters on site. Moreover, the COHb content in the blood should be routinely determined in all patients admitted to an emergency department with unspecific symptoms.
Accidental carbon monoxide poisoning during yagya for faith healing--a case report.
Behera, C; Millo, T M; Jaiswal, A; Dogra, T D
2013-03-01
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.
Esquivel-Elizondo, Sofia; Miceli, Joseph; Torres, Cesar I; Krajmalnik-Brown, Rosa
2018-02-01
Medium-chain fatty acids (MCFA) are important biofuel precursors. Carbon monoxide (CO) is a sustainable electron and carbon donor for fatty acid elongation, since it is metabolized to MCFA precursors, it is toxic to most methanogens, and it is a waste product generated in the gasification of waste biomass. The main objective of this work was to determine if the inhibition of methanogenesis through the continuous addition of CO would lead to increased acetate or MCFA production during fermentation of ethanol. The effects of CO partial pressures (P CO ; 0.08-0.3 atm) on methanogenesis, fatty acids production, and the associated microbial communities were studied in batch cultures fed with CO and ethanol. Methanogenesis was partially inhibited at P CO ≥ 0.11 atm. This inhibition led to increased acetate production during the first phase of fermentation (0-19 days). However, a second addition of ethanol (day 19) triggered MCFA production only at P CO ≥ 0.11 atm, which probably occurred through the elongation of acetate with CO-derived ethanol and H 2 :CO 2 . Accordingly, during the second phase of fermentation (days 20-36), the distribution of electrons to acetate decreased at higher P CO , while electrons channeled to MCFA increased. Most probably, Acetobacterium, Clostridium, Pleomorphomonas, Oscillospira, and Blautia metabolized CO to H 2 :CO 2 , ethanol and/or fatty acids, while Peptostreptococcaceae, Lachnospiraceae, and other Clostridiales utilized these metabolites, along with the provided ethanol, for MCFA production. These results are important for biotechnological systems where fatty acids production are preferred over methanogenesis, such as in chain elongation systems and microbial fuel cells. © 2017 Wiley Periodicals, Inc.
Bihari, Aurelia; Cepinskas, Gediminas; Sanders, David; Lawendy, Abdel-Rahman
2018-05-01
Acute limb compartment syndrome, a complication of musculoskeletal trauma, results in muscle necrosis and cell death. Carbon monoxide, liberated from the carbon monoxide-releasing molecule-3, has been shown protective in a rat model of compartment syndrome. The purpose of this study was to test the effect of carbon monoxide-releasing molecule-3 in a preclinical large animal model of compartment syndrome, with the ultimate goal of developing a pharmacologic adjunct treatment for compartment syndrome. Animal research study. Basic research laboratory in a hospital setting. Male Yorkshire-Landrace pigs (50-60 kg). Pigs underwent 6 hours of intracompartmental pressure elevation by infusing fluid into the anterior compartment of the right hind limb. Carbon monoxide-releasing molecule-3 was administered systemically (2 mg/kg, IV) at fasciotomy, followed by 3-hour reperfusion. Muscle perfusion, inflammation, injury, and apoptosis were assessed in the skeletal muscle. Systemic leukocyte activation was assessed during compartment syndrome and reperfusion. Elevation of hind limb intracompartmental pressure resulted in significant microvascular perfusion deficits (44% ± 1% continuously perfused capillaries in compartment syndrome vs 76% ± 4% in sham; p molecule-3 at fasciotomy increased the number of continuously perfused capillaries (68% ± 3%; p molecule-3 at fasciotomy offered protection against compartment syndrome-induced microvascular perfusion deficit, tissue injury, and systemic leukocyte activation. The data suggest the potential therapeutic application of carbon monoxide-releasing molecule-3 to patients at risk of developing compartment syndrome.
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Alm, S.; Mukala, K.; Tittanen, P.; Jantunen, M.J. [KTL National Public Health Institute, Kuopio (Finland). Dept. of Environmental Health
2001-07-01
The associations of personal carbon monoxide (CO) exposures with ambient air CO concentrations measured at fixed monitoring sites, were studied among 194 children aged 3-6yr in four downtown and four suburban day-care centers in Helsinki, Finland. Each child carried a personal CO exposure monitor between 1 and 4 times for a time period of between 20 and 24h. CO concentrations at two fixed monitoring sites were measured simultaneously. The CO concentrations measured at the fixed monitoring sites were usually lower (mean maximum 8-h concentration: 0.9 and 2.6mgm{sup -3}) than the personal CO exposure concentrations (mean maximum 8-h concentration: 3.3mgm{sup -3}).The fixed site CO concentrations were poor predictors of the personal CO exposure concentrations. However, the correlations between the personal CO exposure and the fixed monitoring site CO concentrations increased (-0.03 -- -0.12 to 0.13-0.16) with increasing averaging times from 1 to 8h. Also, the fixed monitoring site CO concentrations explained the mean daily or weekly personal CO exposures of a group of simultaneously measured children better than individual exposure CO concentrations. This study suggests that the short-term CO personal exposure of children cannot be meaningfully assessed using fixed monitoring sites. (author)
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Metin Uysalol
2011-09-01
Full Text Available Objective: The aim of the study is to analyze the general aspects of cases with carbon monoxide intoxication in order to improve the approach to future patients. Material and Methods: The hospital records of 84 children (mean age 4.71±2.64 years; 48 male, 36 female who had been admitted to Paediatric Emergency Department for carbon monoxide intoxication between October 2007 and February 2009, were retrospectively evaluated in a descriptive analysis.Results: The source of carbon monoxide intoxication was heaters, waterheaters and fi re in 82.1%, 7.1% and 6% of cases, respectively. There was a statistically signifi cant difference between the carboxyhemoglobin levels of the patients according to the clinical classifi cation (p<0.05. The intoxication caused by heaters was observed signifi cantly in November, December and January (p<0.001, between 16:00-24:00 hours (p<0.001 and among more than one member of a family (p<0.001. A medium level correlation was detected between the treatment approach and clinical classifi cation (r=0.50, p<0.001. Conclusion: Carbon monoxide intoxication, in the presented series, was found to develop accidentally; mostly in the Winter season; during night hours when the family members gathered together. The carboxyhemoglobin levels were appropriate with the developing clinical findings. Carboxyhemoglobin level solely was not enough for achieving the diagnosis and planning the treatment.
Mineral CO2 sequestration by steel slag carbonation
International Nuclear Information System (INIS)
Huijgen, W.J.J.; Comans, R.N.J.; Witkamp, G.J.
2005-12-01
Mineral CO2 sequestration, i.e., carbonation of alkaline silicate Ca/Mg minerals, analogous to natural weathering processes, is a possible technology for the reduction of carbon dioxide emissions to the atmosphere. In this paper, alkaline Ca-rich industrial residues are presented as a possible feedstock for mineral CO2 sequestration. These materials are cheap, available near large point sources of CO2, and tend to react relatively rapidly with CO2 due to their chemical instability. Ground steel slag was carbonated in aqueous suspensions to study its reaction mechanisms. Process variables, such as particle size, temperature, carbon dioxide pressure, and reaction time, were systematically varied, and their influence on the carbonation rate was investigated. The maximum carbonation degree reached was 74% of the Ca content in 30 min at 19 bar pressure, 100C, and a particle size of <38 μm. The two must important factors determining the reaction rare are particle size (<2 mm to <38 μm) and reaction temperature (25-225C). The carbonation reaction was found to occur in two steps: (1) leaching of calcium from the steel slag particles into the solution; (2) precipitation of calcite on the surface of these particles. The first step and, more in particular, the diffusion of calcium through the solid matrix toward the surface appeared to be the rate-determining reaction step, The Ca diffusion was found to be hindered by the formation of a CaCO3-coating and a Ca-depleted silicate zona during the carbonation process. Research on further enhancement of the reaction rate, which would contribute to the development of a cost-effective CO2-sequestration process, should focus particularly on this mechanism
Carbon balance of CO2-EOR for NCNO classification
Energy Technology Data Exchange (ETDEWEB)
Nunez-Lopez, Vanessa [The University of Texas at Austin; Gil-Egui, Ramon; Gonzalez-Nicolas, Ana; Hovorka, Susan D
2017-03-18
The question of whether carbon dioxide enhanced oil recovery (CO2-EOR) constitutes a valid alternative for greenhouse gas emission reduction has been frequently asked by the general public and environmental sectors. Through this technology, operational since 1972, oil production is enhanced by injecting CO2 into depleted oil reservoirs in order displace the residual oil toward production wells in a solvent/miscible process. For decades, the CO2 utilized for EOR has been most commonly sourced from natural CO2 accumulations. More recently, a few projects have emerged where anthropogenic CO2 (A-CO2) is captured at an industrial facility, transported to a depleted oil field, and utilized for EOR. If carbon geologic storage is one of the project objectives, all the CO2 injected into the oil field for EOR could technically be stored in the formation. Even though the CO2 is being prevented from entering the atmosphere, and permanently stored away in a secured geologic formation, a question arises as to whether the total CO2 volumes stored in order to produce the incremental oil through EOR are larger than the CO2 emitted throughout the entire CO2-EOR process, including the capture facility, the EOR site, and the refining and burning of the end product. We intend to answer some of these questions through a DOE-NETL funded study titled “Carbon Life Cycle Analysis of CO2-EOR for Net Carbon Negative Oil (NCNO) Classification”. NCNO is defined as oil whose carbon emissions to the atmosphere, when burned or otherwise used, are less than the amount of carbon permanently stored in the reservoir in order to produce the oil. In this paper, we focus on the EOR site in what is referred to as a gate-to-gate system, but are inclusive of the burning of the refined product, as this end member is explicitly stated in the definition of NCNO. Finally, we use Cranfield, Mississippi, as a case study and come to the conclusion that the incremental oil produced is net carbon negative.
Chen, H.; Karion, A.; Rella, C. W.; Winderlich, J.; Gerbig, C.; Filges, A.; Newberger, T.; Sweeney, C.; Tans, P. P.
2013-04-01
Accurate measurements of carbon monoxide (CO) in humid air have been made using the cavity ring-down spectroscopy (CRDS) technique. The measurements of CO mole fractions are determined from the strength of its spectral absorption in the near-infrared region (~1.57 μm) after removing interferences from adjacent carbon dioxide (CO2) and water vapor (H2O) absorption lines. Water correction functions that account for the dilution and pressure-broadening effects as well as absorption line interferences from adjacent CO2 and H2O lines have been derived for CO2 mole fractions between 360-390 ppm and for reported H2O mole fractions between 0-4%. The line interference corrections are independent of CO mole fractions. The dependence of the line interference correction on CO2 abundance is estimated to be approximately -0.3 ppb/100 ppm CO2 for dry mole fractions of CO. Comparisons of water correction functions from different analyzers of the same type show significant differences, making it necessary to perform instrument-specific water tests for each individual analyzer. The CRDS analyzer was flown on an aircraft in Alaska from April to November in 2011, and the accuracy of the CO measurements by the CRDS analyzer has been validated against discrete NOAA/ESRL flask sample measurements made on board the same aircraft, with a mean difference between integrated in situ and flask measurements of -0.6 ppb and a standard deviation of 2.8 ppb. Preliminary testing of CRDS instrumentation that employs improved spectroscopic model functions for CO2, H2O, and CO to fit the raw spectral data (available since the beginning of 2012) indicates a smaller water vapor dependence than the models discussed here, but more work is necessary to fully validate the performance. The CRDS technique provides an accurate and low-maintenance method of monitoring the atmospheric dry mole fractions of CO in humid air streams.
Directory of Open Access Journals (Sweden)
H. Chen
2013-04-01
Full Text Available Accurate measurements of carbon monoxide (CO in humid air have been made using the cavity ring-down spectroscopy (CRDS technique. The measurements of CO mole fractions are determined from the strength of its spectral absorption in the near-infrared region (~1.57 μm after removing interferences from adjacent carbon dioxide (CO2 and water vapor (H2O absorption lines. Water correction functions that account for the dilution and pressure-broadening effects as well as absorption line interferences from adjacent CO2 and H2O lines have been derived for CO2 mole fractions between 360–390 ppm and for reported H2O mole fractions between 0–4%. The line interference corrections are independent of CO mole fractions. The dependence of the line interference correction on CO2 abundance is estimated to be approximately −0.3 ppb/100 ppm CO2 for dry mole fractions of CO. Comparisons of water correction functions from different analyzers of the same type show significant differences, making it necessary to perform instrument-specific water tests for each individual analyzer. The CRDS analyzer was flown on an aircraft in Alaska from April to November in 2011, and the accuracy of the CO measurements by the CRDS analyzer has been validated against discrete NOAA/ESRL flask sample measurements made on board the same aircraft, with a mean difference between integrated in situ and flask measurements of −0.6 ppb and a standard deviation of 2.8 ppb. Preliminary testing of CRDS instrumentation that employs improved spectroscopic model functions for CO2, H2O, and CO to fit the raw spectral data (available since the beginning of 2012 indicates a smaller water vapor dependence than the models discussed here, but more work is necessary to fully validate the performance. The CRDS technique provides an accurate and low-maintenance method of monitoring the atmospheric dry mole fractions of CO in humid air streams.
CO/sub 2/ carbon cycle and climate interactions
Energy Technology Data Exchange (ETDEWEB)
Grassl, H; Maier-Reimer, E; Degens, E T; Kempe, S; Spitzy, A
1984-03-01
Past and expected emissions of anthropogenic CO/sub 2/ stimulate carbon cycle and climate research. Prognoses of future CO/sub 2/ levels depend on energy scenarios and on the reaction of the biosphere and hydrosphere to elevated atmospheric CO/sub 2/ concentrations. The reaction of the reservoirs vegetation, freshwater and oceans to disturbances of the carbon cycle is reviewed. For the oceans first results of a simple carbon cycle model implanted in a three-dimensional general circulation model are presented. This model allows experiments not possible with previous box models.
Risk and protective behaviours for residential carbon monoxide poisoning.
Rupert, Douglas J; Poehlman, Jon A; Damon, Scott A; Williams, Peyton N
2013-04-01
Unintentional, non-fire-related carbon monoxide (CO) poisoning is a leading cause of poisoning death and injury in the USA. Residential poisonings caused by faulty furnaces are the most common type of CO exposure. However, these poisonings are largely preventable with annual furnace inspections and CO alarm installation. This study aimed to identify the knowledge, attitudes and beliefs that might lead consumers to adopt these protective behaviours. In August 2009, four focus groups (n=29) were conducted with homeowners in Chicago, Illinois, USA, to identify the knowledge, attitudes and beliefs that lead consumers to adopt risk and protective behaviours. Discussions were transcribed and the findings were analysed using an ordered meta-matrix. Focus group participants were aware of CO poisoning and supported the idea of regular furnace inspections. However, few participants consistently scheduled professional inspections for fear of costly repairs and unscrupulous contractors. Participants often owned CO alarms, but many did not locate them properly, nor maintain them. Some participants confused CO and natural gas and were unsure how to react if a CO alarm sounds. Participants stated that incentives, such as discounts and inspector selection tips, would make them more likely to schedule furnace inspections. Participants also identified trustworthy sources for CO education, including realtors, fire departments, home insurance agents and local media outlets. Participants' residential CO risk behaviours are not random but driven by underlying knowledge, attitudes and beliefs. Correcting misperceptions, providing incentives and partnering with trustworthy sources might encourage greater consumer adoption of protective behaviours.
Energy Technology Data Exchange (ETDEWEB)
Sasai, A
1974-03-01
The actual condition of carbon monoxide content in expired air and its relation to life-environmental and physical factors was investigated in 277 pregnant women. Subjects residing in a midtown area of Tokyo have average CO concentrations in the expired air slightly higher than those previously reported. Seventy two women (26%) have CO concentrations over 10 ppM. The concentration of CO in expired air correlates with the CO level in the immediate life environment of the individual. Pregnant women with a history of abnormal gestation and/or abnormal delivery are more frequent in the areas with those exhibiting higher CO concentrations in expired air, compared to regions with women showing lower CO levels.
Jarvis, M J; Russell, M A; Feyerabend, C
1983-01-01
Seven non-smokers were exposed to tobacco smoke under natural conditions for two hours in a public house. Measures of nicotine and cotinine in plasma, saliva, and urine and expired air carbon monoxide all showed reliable increases. The concentrations of carbon monoxide and nicotine after exposure averaged 15.7% and 7.5% respectively of the values found in heavy smokers. Although the increase in expired air carbon monoxide of 5.9 ppm was similar to increases in smokers after a single cigarette, the amount of nicotine absorbed was between a tenth and a third of the amount taken in from one cigarette. Since this represented a relatively extreme acute natural exposure, any health risks of passive smoking probably depend less on quantitative factors than on qualitative differences between sidestream and mainstream smoke. PMID:6648864
Hsu, Der-Jen; Huang, Hsiao-Lin
2009-12-01
Although airborne pollutants in urban buses have been studied in many cities globally, long-distance buses running mainly on highways have not been addressed in this regard. This study investigates the levels of volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO 2) and particulate matter (PM) in the long-distance buses in Taiwan. Analytical results indicate that pollutants levels in long-distance buses are generally lower than those in urban buses. This finding is attributable to the driving speed and patterns of long-distance buses, as well as the meteorological and geographical features of the highway surroundings. The levels of benzene, toluene, ethylbenzene and xylene (BTEX) found in bus cabins exceed the proposed indoor VOC guidelines for aromatic compounds, and are likely attributable to the interior trim in the cabins. The overall average CO level is 2.3 ppm, with higher average level on local streets (2.9 ppm) than on highways (2.2 ppm). The average CO 2 level is 1493 ppm, which is higher than the guideline for non-industrial occupied settings. The average PM level in this study is lower than those in urban buses and IAQ guidelines set by Taiwan EPA. However, the average PM 10 and PM 2.5 is higher than the level set by WHO. Besides the probable causes mentioned above, fewer passenger movements and less particle re-suspension from bus floor might also cause the lower PM levels. Measurements of particle size distribution reveal that more than 75% of particles are in submicron and smaller sizes. These particles may come from the infiltration from the outdoor air. This study concludes that air exchange rates in long-distance buses should be increased in order to reduce CO 2 levels. Future research on long-distance buses should focus on the emission of VOCs from brand new buses, and the sources of submicron particles in bus cabins.
Extension of the code COCOSYS to a dispersion code for smoke and carbon monoxide
International Nuclear Information System (INIS)
Sdouz, Gert; Mayrhofer, Robert
2009-01-01
The code COCOSYS (Containment Code SYStem) was developed by GRS in Germany to simulate processes and nuclear plant states during severe accidents in the containments of light water reactors. It contains several physical models, especially a module for aerosol behaviour. The goal of this work was to extend COCOSYS for applications in more general geometries mainly for complex public buildings. For the application in public buildings models for air condition systems and different boundary conditions according to different environments were developed. The principal application of the extended code COCOSYS is in the area of emergency situations especially in the simulation for carbon monoxide and smoke dispersion. After developing and implementing the new models several test calculations were performed to evaluate the functionality of the extended code. The comparison of the results with those of the original COCOSYS code showed no discrepancies. For the first realistic application several fire emergency scenarios in the Vienna General Hospital (AKH) were selected in agreement with the fire department of the hospital. One of the scenarios addresses the danger of carbon monoxide (CO) and smoke leaking into a fire protection section through a damaged fire protection flap. As a result of the dispersion simulation the CO-concentration in all of the rooms is obtained. Together with additional results as deposition and smoke dispersion the outcome of the simulation can be used for training. Among the next steps are the validation of the new models and the selection of critical scenarios. (author)
Directory of Open Access Journals (Sweden)
Fatma Polat
2012-09-01
Full Text Available Delayed encephalopathy (DE is a neuropsychiatric syndrome that can arise generally within 20 days of acute carbon monoxide (CO intoxication after apparent recovery and involves variable degrees of cognitive deficits, personality changes, movement disorders and focal neurologic deficits. We report a 35-year-old female patient with delayed encephalopathy due to CO intoxication, presenting with cognitive impairment and mild parkinsonism despite receiving hyberbaric oxigen therapy (HBO. Magnetic resonance imaging showed abnormal signal intensity and decreased diffusivity at both caudate nuclei and globus pallidus. She continued to receive additional HBO therapy and complete recovery was reached within six months. The positive effect of early HBO therapy of selected patients in reversing the acute effects of CO intoxication is appearant. We here also review the beneficial effect of HBO in preventing or limitating the late neurocognitive deficits associated with severe CO intoxication
Kinetic study of uranium carburization by different carbonated gases
International Nuclear Information System (INIS)
Feron, Guy
1963-01-01
The kinetic study of the reaction U + CO 2 and U + CO has been performed by a thermogravimetric method on a spherical uranium powder, in temperature ranges respectively from 460 to 690 deg. C and from 570 to 850 deg. C. The reaction with carbon dioxide leads to uranium dioxide. A carbon deposition takes place at the same time. The global reactions is the result of two reactions: U + 2 CO 2 → UO 2 + 2 CO U + CO 2 → UO 2 + C The reaction with carbon monoxide leads to a mixture of dioxide UO 2 , dicarbide UC 2 and free carbon. The main reaction can be written. U + CO → 1/2 UO 2 + 1/2 UC 2 The free carbon results of the disproportionation of the carbon monoxide. A remarkable separation of the two phases UO 2 and UC 2 can be observed. A mechanism accounting for the phenomenon has been proposed. The two reactions U + CO 2 and U + CO begin with a long germination period, after which, the reaction velocity seems to be limited in both cases by the ionic diffusion of oxygen through the uranium dioxide. (author) [fr
Erythropoietin in the treatment of carbon monoxide neurotoxicity in rat.
Moallem, Seyed Adel; Mohamadpour, Amir Hooshang; Abnous, Khalil; Sankian, Mojtaba; Sadeghnia, Hamid Reza; Tsatsakis, Aristidis; Shahsavand, Shabnam
2015-12-01
Erythropoietin (EPO) plays a critical role in the development of the nervous system. In this study, the effects of EPO in carbon monoxide (CO) neurotoxicity were examined. Rats were exposed to 3000 ppm CO for 1 h and then different doses of EPO were administrated intraperitoneally. After 24 h, glial fibrillary acidic protein (GFAP) levels in the serum were determined and water content of brain and the extravasation of a tracer (Evans blue) were measured. Brain lipid peroxidation, myeloperoxidase activity Myelin basic protein (MBP) and BAX/BcL2 protein relative expressions were determined. Cation exchange chromatography was used to evaluate MBP alterations. Seven days after exposure, pathological assessment was performed after Klüver-Barrera staining. EPO reduced malondialdehyde levels at all doses (2500, 5000 and 10,000 u/kg). Lower doses of EPO (625, 1250, 2500 u/kg) significantly decreased the elevated serum levels of GFAP. EPO could not reduce the water content of the edematous poisoned brains. However, at 5000 and 10,000 u/kg it protected the blood brain barrier against integrity loss as a result of CO. EPO could significantly decrease the MPO activity. CO-mediated oxidative stress caused chemical alterations in MBP and EPO could partially prevent these biochemical changes. Fewer vacuoles and demyelinated fibers were found in the EPO-treated animals. EPO (5000 u/kg) could restore the MBP density. CO increased brain BAX/Bcl-2 ratio 38.78%. EPO reduced it 38.86%. These results reveal that EPO could relatively prevent different pathways of neurotoxicity by CO poisoning and thus has the potential to be used as a novel approach to manage this poisoning. Copyright © 2015 Elsevier Ltd. All rights reserved.
Exposure to Elevated Carbon Monoxide Levels at an Indoor Ice Arena--Wisconsin, 2014.
Creswell, Paul D; Meiman, Jon G; Nehls-Lowe, Henry; Vogt, Christy; Wozniak, Ryan J; Werner, Mark A; Anderson, Henry
2015-11-20
On December 13, 2014, the emergency management system in Lake Delton, Wisconsin, was notified when a male hockey player aged 20 years lost consciousness after participation in an indoor hockey tournament that included approximately 50 hockey players and 100 other attendees. Elevated levels of carbon monoxide (CO) (range = 45 ppm-165 ppm) were detected by the fire department inside the arena. The emergency management system encouraged all players and attendees to seek medical evaluation for possible CO poisoning. The Wisconsin Department of Health Services (WDHS) conducted an epidemiologic investigation to determine what caused the exposure and to recommend preventive strategies. Investigators abstracted medical records from area emergency departments (EDs) for patients who sought care for CO exposure during December 13-14, 2014, conducted a follow-up survey of ED patients approximately 2 months after the event, and conducted informant interviews. Ninety-two persons sought ED evaluation for possible CO exposure, all of whom were tested for CO poisoning. Seventy-four (80%) patients had blood carboxyhemoglobin (COHb) levels consistent with CO poisoning; 32 (43%) CO poisoning cases were among hockey players. On December 15, the CO emissions from the propane-fueled ice resurfacer were demonstrated to be 4.8% of total emissions when actively resurfacing and 2.3% when idling, both above the optimal range of 0.5%-1.0%. Incomplete fuel combustion by the ice resurfacer was the most likely source of elevated CO. CO poisonings in ice arenas can be prevented through regular maintenance of ice resurfacers, installation of CO detectors, and provision of adequate ventilation.
Potchter, Oded; Oz, Meirav; Brenner, Shmuel; Yaakov, Yaron; Schnell, Izhak
2014-12-01
Short-term personal exposure of passengers in different types of motor vehicles to carbon monoxide was investigated in an intensively used main road in Israel's Tel Aviv metropolitan area. According to monitoring stations of the Ministry for Environmental Protection (MEP), concentrations of carbon monoxide (CO) along the road, at a height of 3 m above pedestrian level, in the Tel Aviv metropolitan area, are currently very low. However, these measurements do not reflect the actual exposure of commuters, which were the main objective of this study. Four vehicle types/travel modes were investigated: private cars with closed windows, private cars with open windows, motorcycles, and buses. The commuter CO average exposure was the accumulative exposure divided by the duration of the sampling taken along the route, for each type of vehicles. The results showed that commuters in cars with closed windows were exposed to the highest mean CO level, 27.2 ppm, for a period of 38 min; those in a car with open windows, to 19.7 ppm for 38 min; motorcycle riders, to 12.8 ppm, for 17 min; and bus users were exposed to the lowest mean pollution level, of only 3.6 ppm, for 25 min. Thus, CO values of 1 to 3 ppm, as measured at an MEP adjacent monitoring station, may indicate the exposure to CO pollution of area residents, but do not represent the actual exposure of commuters on the congested main road.
Carbon monoxide exposures inside an automobile traveling on an urban arterial highway.
Ott, W; Switzer, P; Willits, N
1994-08-01
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. On each trip (lasting between 31 and 61 minutes), the test vehicle drove the same 5.9-mile segment of roadway in both directions, for a total of 11.8 miles, passing through 20 intersections with traffic lights (10 in each direction) in three California cities (Menlo Park, Palo Alto, and Los Altos). Earlier tests showed that the test vehicle was free of CO intrusion. For the 88 trips, the mean CO concentration was 9.8 ppm, with a standard deviation of 5.8 ppm. Of nine covariates that were examined to explain the variability in the mean CO exposures observed on the 88 trips (ambient CO at two fixed stations, atmospheric stability, seasonal trend function, time of day, average surrounding vehicle count, trip duration, proportion of time stopped at lights, and instrument type), a fairly strong seasonal trend was found. A model consisting of only a single measure of traffic volume and a seasonal trend component had substantial predictive power (R2 = 0.68); by contrast, the ambient CO levels, although partially correlated with average exposures, contributed comparatively little predictive power to the model. The CO exposures experienced while drivers waited at the red lights at an intersection ranged from 6.8 to 14.9 ppm and differed considerably from intersection to intersection.(ABSTRACT TRUNCATED AT 250 WORDS)
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C. Helfter
2016-08-01
Full Text Available We report on more than 3 years of measurements of fluxes of methane (CH4, carbon monoxide (CO and carbon dioxide (CO2 taken by eddy-covariance in central London, UK. Mean annual emissions of CO2 in the period 2012–2014 (39.1 ± 2.4 ktons km−2 yr−1 and CO (89 ± 16 tons km−2 yr−1 were consistent (within 1 and 5 % respectively with values from the London Atmospheric Emissions Inventory, but measured CH4 emissions (72 ± 3 tons km−2 yr−1 were over two-fold larger than the inventory value. Seasonal variability was large for CO with a winter to summer reduction of 69 %, and monthly fluxes were strongly anti-correlated with mean air temperature. The winter increment in CO emissions was attributed mainly to vehicle cold starts and reduced fuel combustion efficiency. CO2 fluxes were 33 % higher in winter than in summer and anti-correlated with mean air temperature, albeit to a lesser extent than for CO. This was attributed to an increased demand for natural gas for heating during the winter. CH4 fluxes exhibited moderate seasonality (21 % larger in winter, and a spatially variable linear anti-correlation with air temperature. Differences in resident population within the flux footprint explained up to 90 % of the spatial variability of the annual CO2 fluxes and up to 99 % for CH4. Furthermore, we suggest that biogenic sources of CH4, such as wastewater, which is unaccounted for by the atmospheric emissions inventories, make a substantial contribution to the overall budget and that commuting dynamics in and out of central business districts could explain some of the spatial and temporal variability of CO2 and CH4 emissions. To our knowledge, this study is unique given the length of the data sets presented, especially for CO and CH4 fluxes. This study offers an independent assessment of "bottom-up" emissions inventories and demonstrates that the urban sources of CO and CO2 are well characterized in
EPIDEMIOLOGY OF CARBON MONOXIDE POISONING IN LJUBLJANA FROM 1990 TO 1999
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Miran Brvar
2002-02-01
Full Text Available Background. Carbon monoxide (CO is the most common lethal poisoning. The incidence of sublethal CO poisoning in Slovenia is not known. The aim of the study was to investigate the epidemiology of sublethal acute CO poisoning in Ljubljana region (Slovenia.Methods. A retrospective study involved CO poisoned patients admited to Poison Control Centre and Centre of Intensive Care Medicine of the University Medical Centre Ljubljana, between January 1, 1990 and December 31, 1999.Results. There were annualy approximately 2.4 cases of sublethal CO poisonings per 100.000 population in Ljubljana region. Of these, 25% were suicide attempts and 75% were unintentional poisonings (28% happened in domestic environment as a result of heating, cooking or bathing, 22% were associated with fire, 11% happened in the working site, 10% happened in the workroom at home and only 3% occurred in the moving vehicle. Among the patients there were 72% male and 28% female. The domestic source of CO was a gas water heater or residential heating device in the 63% of the cases, a coal stove in the 32% and an oil heater in the 6%. In the 18% of the suicide attempts we found also acute drug or alcohol intoxication, and 18% of patients poisoned in the fire were intoxicated with alcohol. Collective poisoning happened in the 25% of cases affecting from 2 to 6 persons.Conclusions. The incidence of sublethal CO poisoning in Ljubljana region appers to be seven times lower than in other countries. The main reason is misdiagnosing of CO poisoning. In the future we should consider CO poisoning more often, particularly in all patients with flu-like symptoms, unexplained headache and worsening of pre-existing diseases. We should always exclude the collective poisoning and the presence of alcohol or other drugs.
Borsdorff, Tobias; Andrasec, Josip; aan de Brugh, Joost; Hu, Haili; Aben, Ilse; Landgraf, Jochen
2018-05-01
In the perspective of the upcoming TROPOMI Sentinel-5 Precursor carbon monoxide data product, we discuss the benefit of using CO total column retrievals from cloud-contaminated SCIAMACHY 2.3 µm shortwave infrared spectra to detect atmospheric CO enhancements on regional and urban scales due to emissions from cities and wildfires. The study uses the operational Sentinel-5 Precursor algorithm SICOR, which infers the vertically integrated CO column together with effective cloud parameters. We investigate its capability to detect localized CO enhancements distinguishing between clear-sky observations and observations with low (Paris, Los Angeles and Tehran as well as the wildfire events in Mexico-Guatemala 2005 and Alaska-Canada 2004. The CO average of the SCIAMACHY full-mission data set of clear-sky observations can detect weak CO enhancements of less than 10 ppb due to air pollution in these cities. For low-cloud conditions, the CO data product performs similarly well. For medium-high clouds, the observations show a reduced CO signal both over Tehran and Los Angeles, while for Paris no significant CO enhancement can be detected. This indicates that information about the vertical distribution of CO can be obtained from the SCIAMACHY measurements. Moreover, for the Mexico-Guatemala fires, the low-cloud CO data captures a strong outflow of CO over the Gulf of Mexico and the Pacific Ocean and so provides complementary information to clear-sky retrievals, which can only be obtained over land. For both burning events, enhanced CO values are even detectable with medium-high-cloud retrievals, confirming a distinct vertical extension of the pollution. The larger number of additional measurements, and hence the better spatial coverage, significantly improve the detection of wildfire pollution using both the clear-sky and cloudy CO retrievals. Due to the improved instrument performance of the TROPOMI instrument with respect to its precursor SCIAMACHY, the upcoming Sentinel-5
SOFT X-RAY IRRADIATION OF PURE CARBON MONOXIDE INTERSTELLAR ICE ANALOGUES
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Ciaravella, A.; Candia, R.; Collura, A. [INAF-Osservatorio Astronomico di Palermo, P.za Parlamento 1, 90134 Palermo (Italy); Jimenez-Escobar, A.; Munoz Caro, G. M. [Centro de Astrobiologia (CSIC-INTA), Carretera de Ajalvir, km 4, Torrejon de Ardoz, 28850 Madrid (Spain); Cecchi-Pestellini, C. [INAF-Osservatorio Astronomico di Cagliari, Strada n.54, Loc. Poggio dei Pini, I-09012 Capoterra (Italy); Giarrusso, S. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, Via U. La Malfa 153, I-90146 Palermo (Italy); Barbera, M., E-mail: aciaravella@astropa.unipa.it [Dipartimento di Scienze Fisiche and Astronomiche, Universita di Palermo, Sezione di Astronomia, Piazza del Parlamento 1, I-90134 Palermo (Italy)
2012-02-10
There is an increasing evidence for the existence of large organic molecules in the interstellar and circumstellar medium. Very few among such species are readily formed in conventional gas-phase chemistry under typical conditions of interstellar clouds. Attention has therefore focused on interstellar ices as a potential source of these relatively complex species. Laboratory experiments show that irradiation of interstellar ice analogues by fast particles or ultraviolet radiation can induce significant chemical complexity. However, stars are sources of intense X-rays at almost every stage of their formation and evolution. Such radiation may thus provide chemical changes in regions where ultraviolet radiation is severely inhibited. After H{sub 2}O, CO is often the most abundant component of icy grain mantles in dense interstellar clouds and circumstellar disks. In this work we present irradiation of a pure carbon monoxide ice using a soft X-ray spectrum peaked at 0.3 keV. Analysis of irradiated samples shows formation of CO{sub 2}, C{sub 2}O, C{sub 3}O{sub 2}, C{sub 3}, C{sub 4}O, and CO{sub 3}/C{sub 5}. Comparison of X-rays and ultraviolet irradiation experiments, of the same energy dose, shows that X-rays are more efficient than ultraviolet radiation in producing new species. With the exception of CO{sub 2}, X-ray photolysis induces formation of a larger number of products with higher abundances, e.g., C{sub 3}O{sub 2} column density is about one order of magnitude higher in the X-ray experiment. To our knowledge this is the first report on X-ray photolysis of CO ices. The present results show that X-ray irradiation represents an efficient photo-chemical way to convert simple ices to more complex species.
The Role of Oxygen Therapies in Carbon Monoxide Poisoning
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Suleyman Metin
2011-08-01
Full Text Available Due to climate and socio-economic issues in Turkey, the incidence of carbon monoxide (CO poisoning is high, especially in winter. Clinical manifestations may vary depending on the type of CO source, concentration and duration of exposure. The symptoms of CO poisoning predominantly manifest in lots of organs and systems with high oxygen utilization, especially the brain and the heart. The primary aim in oxygen therapy is to eliminate CO and to reduce its toxic effects. In this context, normobaric and hyperbaric oxygen therapy are used to achieve these goals. Normobaric oxygen (NBO treatment is an easily accessible and relatively not expensive modality, where hyperbaric oxygen (HBO therapy requires specific equipment, certified staff and is available only in some centers. Additionally, HBO treatment has several additional advantages over NBO treatment. Despite its benefits, it is compulsory to search for some criteria in selecting patients to be treated because of the limited availability and access of hyperbaric facilities. For an effective evaluation and an optimal treatment, advanced education of the healthcare professionals on the use of oxygen delivery modalities in the management of CO poisoning is imperative. In this review, it has been aimed to outline the significance of oxygen treatment modalities and to determine patient selection criteria for HBO treatment in the management of CO poisoning which continues to be an important threat to community health care. [TAF Prev Med Bull 2011; 10(4.000: 487-494
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G. Song
2013-06-01
Full Text Available Spectrally resolved efficiency (i.e. apparent quantum yield, AQY of carbon monoxide (CO photoproduction is a useful indicator of substrate photoreactivity and a crucial parameter for modeling CO photoproduction rates in the water column. Recent evidence has suggested that CO photoproduction from particles in marine waters is significant compared to the well-known CO production from chromophoric dissolved organic matter (CDOM photodegradation. Although CDOM-based CO AQY spectra have been extensively determined, little is known of this information on the particulate phase. Using water samples collected from the Mackenzie estuary, shelf, and Canada Basin in the southeastern Beaufort Sea, the present study for the first time quantified the AQY spectra of particle-based CO photoproduction and compared them with the concomitantly determined CDOM-based CO AQY spectra. CO AQYs of both particles and CDOM decreased with wavelength but the spectral shape of the particulate AQY was flatter in the visible regime. This feature resulted in a disproportionally higher visible light-driven CO production by particles, thereby increasing the ratio of particle- to CDOM-based CO photoproduction with depth in the euphotic zone. In terms of depth-integrated production in the euphotic zone, CO formation from CDOM was dominated by the ultraviolet (UV, 290–400 nm radiation whereas UV and visible light played roughly equal roles in CO production from particles. Spatially, CO AQY of bulk particulate matter (i.e. the sum of organics and inorganics augmented from the estuary and shelf to the basin while CO AQY of CDOM trended inversely. Water from the deep chlorophyll maximum layer revealed higher CO AQYs than did surface water for both particles and CDOM. CO AQY of bulk particulate matter exceeded that of CDOM on the shelf and in the basin, but the sequence reversed in the estuary. Without consideration of the potential role of metal oxides (e.g. iron oxides in particle
Leigh-Smith, Simon; Watt, Ian; McFadyen, Angus; Grant, Stan
2004-01-01
To determine whether using a camping stove to bring a pan of ice to boiling point produces higher carbon monoxide (CO) concentration than would bringing a pan of water to boiling point. The hypothesis was that ice would cause greater CO concentration because of its greater flame-cooling effect and, consequently, more incomplete combustion. This was a randomized, prospective observational study. After an initial pilot study, CO concentration was monitored during 10 trials for each of ice and water. A partially ventilated 200-L cardboard box model was developed and then used inside a chamber at -6 degrees C. Ice temperature and volume, water temperature and volume, pan size, and flame characteristics were all standardized. Temperature of the heated medium was monitored to determine time to boiling point. Carbon monoxide concentration was monitored every 30 seconds for the first 3 minutes, then every minute until the end of each 10-minute trial. There was no significant difference (P > .05) in CO production levels between ice and water. Each achieved a similar mean plateau level of approximately 400 ppm CO concentration with a similar rate of rise. However, significantly higher (P = .014) CO concentration occurred at 4 and 5 minutes when the flame underwent a yellow flare; this occurred only on 3 occasions when ice was the medium. There were no significant differences for CO production between bringing a pan of ice or water to boiling point. In a small number of ice trials, the presence of a yellow flame resulted in high CO concentration. Yellow flares might occur more often with ice or snow melting, but this has not been proven.
Mesoporous carbon composite for CO{sub 2} capture
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Hwang, Chih-Chau; Jin, Zhong; Lu, Wei; Sun, Zhengzong; Alemany, Lawrence; Tour, James M. [Rice University, Houston, TX (United States); Lomeda, Jay R.; Flatt, Austen K. [Nalco Company, Naperville, IL (United States)
2012-07-01
Herein we report a carbon based technology that can be used to rapidly adsorb and release CO{sub 2}. CO{sub 2} uptake by the synthesized composites was determined using a gravimetric method at room temperature and atmospheric pressure. 39% polyethylenimine-mesocarbon (PEI-CMK-3) composite had {approx} 12 wt% CO{sub 2} uptake capacity and a 37% polyvinylamine meso-carbon (PVA-CMK-3) composite had {approx} 13 wt% CO{sub 2} uptake capacity. The sorbents were easily regenerated at 75 deg C and exhibit excellent stability over multiple regeneration cycles. CO{sub 2} uptake was equivalent when using 10% CO{sub 2} in 90% CH{sub 4}, C{sub 2}H{sub 6} and C{sub 3}H{sub 9} mixture, underscoring the efficacy for CO{sub 2} separation from natural gas. (author)
Potential use of hyperoxygenated solution as a treatment strategy for carbon monoxide poisoning.
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Xingxing Sun
Full Text Available AIM: Carbon monoxide (CO poisoning can cause permanent damage in tissues that are sensitive to hypoxia. We explored the feasibility and efficacy of using a hyperoxygenated solution (HOS to treat severe acute CO poisoning in an animal model. METHODS: Male Sprague-Dawley rats were subjected to CO poisoning. The HOS was administered into the femoral vein of these rats through a catheter (10 ml/kg. Carboxyhemoglobin (COHb and blood gases were used to assess the early damage caused by CO poisoning. S100β was measured to predict the development of late cognitive sequelae of CO. The Morris water maze test was performed to assess cognitive function, and Nissl staining was performed to observe histologic change. RESULTS: The COHb concentrations rapidly decreased at 5 min after the HOS administration; however, the PaO2 and SaO2 in rats treated with HOS increased significantly 5 min after the HOS administration. The S100β concentrations, which increased significantly after CO poisoning, increased at a much slower rate in the rats treated with HOS (HOS group compared with the rats treated with O2 inhalation (O2 group. The escape latency in the place navigation test was shortened after CO poisoning on days 11-15 and days 26-30, and the swimming time in quadrant 4 in the spatial probe test on days 15 and 30 after CO poisoning was prolonged in the rats treated with HOS injection compared with the rats treated with oxygen inhalation or normal saline injection. The neuronal degeneration in the HOS group was alleviated than that in the CO or O2 group. CONCLUSION: HOS efficiently alleviates the brain damage in acute CO-poisoned rats and thus may serve as a new way to treat human patients with CO poisoning in clinical practice.
Teerapuncharoen, Krittika; Sharma, Nirmal S; Barker, Andrew B; Wille, Keith M; Diaz-Guzman, Enrique
2015-09-01
Carbon monoxide (CO) is the most common cause of poisoning and poisoning-related death in the United States. It is a tasteless and odorless poisonous gas produced from incomplete combustion of hydrocarbons, such as those produced by cars and heating systems. CO rapidly binds to hemoglobin to form carboxyhemoglobin, leading to tissue hypoxia, multiple-organ failure, and cardiovascular collapse. CO also binds to myocardial myoglobin, preventing oxidative phosphorylation in cardiac mitochondria and resulting in cardiac ischemia or stunning and cardiogenic pulmonary edema. Treatment of CO poisoning is mainly supportive, and supplemental oxygen remains the cornerstone of therapy, whereas hyperbaric oxygen therapy is considered for patients with evidence of neurological and myocardial injury. Extracorporeal membrane oxygenation (ECMO) has been utilized effectively in patients with respiratory failure and hemodynamic instability, but its use has rarely been reported in patients with CO poisoning. We report the successful use of venoarterial ECMO in a patient with severe CO poisoning and multiple-organ failure. Copyright © 2015 by Daedalus Enterprises.
Adsorption and methanation of carbon dioxide on a nickel/silica catalyst
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Falconer, J.L.; Zagli, A.E.
1980-04-01
Temperature-programed desorption and reaction studies showed that increasing amounts of CO/sub 2/ adsorbed on silica-supported 6.9% nickel with increasing temperature to a maximum adsorption at approx. 443/sup 0/K, i.e., that the adsorption was activated; that CO/sub 2/ desorbed partly as CO/sub 2/ with the peak at 543/sup 0/K, and partly as CO with several peaks; that in the presence of hydrogen, nearly all adsorbed CO/sub 2/ desorbed as methane, and a small amount as CO; and that the methane desorption peaks from adsorbed CO and CO/sub 2/ both occurred at 473/sup 0/K. These results suggested that carbon dioxide adsorbed dissociatively as a carbon monoxide and an oxygen species. An observed absence of higher hydrocarbons in the methanation products of carbon dioxide was attributed to a high hydrogen/carbon monoxide surface ratio caused by the activated carbon dioxide adsorption.
Acute wood or coal exposure with carbon monoxide intoxication induces sister chromatid exchange
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Ozturk, S.; Vatansever, S.; Cefle, K.; Palanduz, S.; Guler, K.; Erten, N.; Erk, O.; Karan, M.A.; Tascioglu, C. [University of Istanbul, Istanbul (Turkey). Istanbul Faculty of Medicine
2002-07-01
The object of this study was to investigate the genotoxic effect of acute overexposure to combustion products originating from coal or wood stoves in patients presenting with acute carbon monoxide intoxication. The authors analyzed the frequency of sister chromatid exchange and the carboxyhemoglobin concentration in 20 consecutive patients without a history of smoking or drug use who had been treated in the Emergency Care Unit of Istanbul Medical Faculty due to acute carbon monoxide intoxication. All of these cases were domestic accidents due to dysfunctioning coal or wood stoves. The results were compared with a control group of 20 nonsmoking, nondrug-using healthy individuals matched for age, sex, and absence of other chemical exposure. It was concluded that acute exposure to combustion products of wood or coal is genotoxic to DNA. Potential causes of genotoxicity include known mutagenic compounds present in coal or wood smoke and ash, oxygen radicals formed during combustion, as well as hypoxic and reperfusion injury mechanisms initiated by carbon monoxide intoxication.
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Wenqing Wu
2016-12-01
Full Text Available During radiotherapy procedures, radiation-induced bystander effect (RIBE can potentially lead to genetic hazards to normal tissues surrounding the targeted regions. Previous studies showed that RIBE intensities in cell cluster models were much higher than those in monolayer cultured cell models. On the other hand, low-concentration carbon monoxide (CO was previously shown to exert biological functions via binding to the heme domain of proteins and then modulating various signaling pathways. In relation, our previous studies showed that exogenous CO generated by the CO releasing molecule, tricarbonyldichlororuthenium (CORM-2, at a relatively low concentration (20 µM, effectively attenuated the formation of RIBE-induced DNA double-strand breaks (DSB and micronucleus (MN. In the present work, we further investigated the capability of a low concentration of exogenous CO (CORM-2 of attenuating or inhibiting RIBE in a mixed-cell cluster model. Our results showed that CO (CORM-2 with a low concentration of 30 µM could effectively suppress RIBE-induced DSB (p53 binding protein 1, p53BP1, MN formation and cell proliferation in bystander cells but not irradiated cells via modulating the inducible nitric oxide synthase (iNOS andcyclooxygenase-2 (COX-2. The results can help mitigate RIBE-induced hazards during radiotherapy procedures.
Precipitation of hydrated Mg carbonate with the aid of carbonic anhydrase for CO2 sequestration
Power, I. M.; Harrison, A. L.; Dipple, G. M.
2011-12-01
Strategies for sequestering CO2 directly from the atmosphere are likely required to achieve the desired reduction in CO2 concentration and avoid the most damaging effects of climate change [1]. Numerous studies have demonstrated the accelerated precipitation of calcium carbonate minerals with the aid of carbonic anhydrase (CA) as a means of sequestering CO2 in solid carbonate form; however, no study has examined precipitation of magnesium carbonate minerals using CA. Precipitation of magnesite (MgCO3) is kinetically inhibited [2]; therefore, Mg2+ must be precipitated as hydrated carbonate minerals. In laboratory experiments, the uptake of atmospheric CO2 into brine solutions (0.1 M Mg) was rate-limiting for the precipitation of dypingite [Mg5(CO3)4(OH)2-5H2O] with initial precipitation requiring 15 days [3]. It was also found that dypingite precipitation outpaced the uptake of CO2 gas into solution. CO2 uptake is limited by the hydration of CO2 to form carbonate ions [4]. Carbonic anhydrase (CA) enzymes are among the fastest known in nature and are able to catalyze the hydration of CO2, i.e., converting CO2(aq) to CO32- and HCO3- [5]. CA plays an important role in the carbon concentrating mechanism of photoautotrophic, chemoautotrophic, and heterotrophic prokaryotes and is involved in pH homeostasis, facilitated diffusion of CO2, ion transport, and the interconversion of CO2 and HCO3- [6]. Introducing CA into buffered Mg-rich solutions should allow for more rapid precipitation of hydrated magnesium carbonate minerals. Batch experiments were conducted using 125 mL flasks containing 100 mL of Millipore deionized water with 0.2 M of MgCl2-6H2O. To buffer pH, 1.0 g of pulverized brucite [Mg(OH)2] or 1.0 g of NaOH was added to the systems, which were amended with Bovine carbonic anhydrase (BCA) (Sigma-Aldrich). Solutions were stirred continuously and kept at room temperature (~22°C) with laboratory air introduced by bubbling. Temperature and pH were measured routinely
Ordered nanoporous carbon for increasing CO2 capture
International Nuclear Information System (INIS)
Yoo, Hye-Min; Lee, Seul-Yi; Park, Soo-Jin
2013-01-01
Ordered nanoporous carbons (ONCs) were prepared using a soft-templating method. The prepared ONCs materials were subjected to a controlled carbonization temperature over the temperature range, 700–1000 °C, to increase the specific surface area and total pore volume of ordered nanoporous carbon followed by carbonization of the phenolic resin. ONCs materials synthesized at various carbonization temperatures were used as adsorbents to improve the CO 2 adsorption efficiency. The surface properties of the ONCs materials were examined by X-ray photoelectron spectroscopy. The structural properties of the ONCs materials were analyzed by X-ray diffraction. The textural properties of the ONCs materials were examined using the N 2 /77 K adsorption isotherms according to the Brunauer–Emmett–Teller equation. The CO 2 adsorption capacity was measured by CO 2 isothermal adsorption at 298 K/30 bar and 298 K/1 bar. The carbonization temperature was found to have a major effect on the CO 2 adsorption capacity, resulting from the specific surface area and total pore volumes of the ONCs materials. - Graphical abstract: This schematic diagram described synthesis of ONCs. Highlights: ► ONCs materials can be prepared readily using the direct-triblock-copolymer-templating method. ► The distributions show that prominent development can be observed around the micro-pore region. ► The soft-templating method provides opportunities for controlling the pore structure of ONCs. ► From thermal power plants for CO2 capture by adsorption technology, is a new direction.
Limberg, Christian; Zimmermann, Philipp; Hoof, Santina; Braun-Cula, Beatrice; Herwig, Christian
2018-04-10
Reduced CO2 species are key intermediates in a variety of natural and synthetic processes. In the majority of systems, however, they elude isolation or characterisation due to high reactivity or limited accessibility (heterogeneous systems) and thus formulations often remain uncertain or based on calculations only. We herein report on a Ni-CO22- complex that is unique in many ways. While its structural and electronic features help understanding the CO2 bound state in Ni,Fe carbon monoxide dehydrogenases, its reactivity sheds light on how CO2 can be converted into CO/CO32- by nickel complexes. In addition, the complex has been generated via a rare example of formate β deprotonation, a mechanistical step relevant to nickel catalysed conversion of HxCOyz- at electrodes and formate oxidation in formate dehydrogenases. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Schmidt, Andres; Rella, Chris W.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Law, Beverly E.
2014-11-01
In recent years, measurements of atmospheric carbon dioxide with high precision and accuracy have become increasingly important for climate change research, in particular to inform terrestrial biosphere models. Anthropogenic carbon dioxide emissions from fossil fuel burning have long been recognized to contribute a significant portion of the carbon dioxide in the atmosphere. Here, we present an approach to remove the traffic related carbon dioxide emissions from mole fractions measured at a tall tower by using the corresponding carbon monoxide measurements in combination with footprint analyses and transport modeling. This technique improves the suitability of the CO2 data to be used in inverse modeling approaches of atmosphere-biosphere exchange that do not account for non-biotic portions of CO2. In our study region in Oregon, road traffic emissions are the biggest source of anthropogenic carbon dioxide and carbon monoxide. A three-day mobile campaign covering 1700 km of roads in northwestern Oregon was performed during summer of 2012 using a laser-based Cavity Ring-Down Spectrometer. The mobile measurements incorporated different roads including main highways, urban streets, and back-roads, largely within the typical footprint of a tall CO/CO2 observation tower in Oregon's Willamette Valley. For the first time, traffic related CO:CO2 emission ratios were measured directly at the sources during an on-road campaign under a variety of different driving conditions. An average emission ratio of 7.43 (±1.80) ppb CO per ppm CO2 was obtained for the study region and applied to separate the traffic related portion of CO2 from the mole fraction time series. The road traffic related portion of the CO2 mole fractions measured at the tower site reached maximum values ranging from 9.8 to 12 ppm, depending on the height above the surface, during summer 2012.
Carbon monoxide oxidation using Zn-Cu-Ti hydrotalcite-derived ...
Indian Academy of Sciences (India)
Multioxide catalysts of zinc, copper and titanium with different ratios obtained from layered double hydroxide (LDH) precursors were used in the oxidation of carbon monoxide. The catalysts were characterized by energy-dispersive X-ray spectrometry, X-ray diffraction, thermal analyses (TG, DTG and DTA) and scanning ...
Cervellin, Gianfranco; Comelli, Ivan; Rastelli, Gianni; Picanza, Alessandra; Lippi, Giuseppe
2014-12-01
The aim of this study was to assess the role of blood lactate levels at admission in carbon monoxide (CO)-poisoned patients for establishing severity of poisoning and short term prognosis. All cases of CO poisoning visited in the emergency department during the years 2012 and 2013 were retrieved from the hospital database. The concentration of COHb and lactate was assessed in arterial blood in all patients with suspected CO poisoning, along with the plasma concentration of troponin I (TnI). The control population for TnI results consisted in 125 blood donors. Twenty three (61%) out of 38 CO-poisoned patients underwent hyperbaric oxygen (HBO) treatment, and 10 (26%) were admitted to a hospital ward. A significant correlation was found between lactate and COHb (r=0.54; p99th percentile compared to 2% controls (p=0.003). The odds ratio for detectable TnI and TnI >99th percentile in CO-poisoned patients were 13.1 (p<0.001) and 7.6 (p=0.006), respectively. Initial blood lactate level may be useful for risk stratification of CO-poisoned patients, especially for predicting hospitalization. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Polarity and Nonpolarity of Ionic Liquids Viewed from the Rotational Dynamics of Carbon Monoxide.
Yasaka, Y; Kimura, Y
2015-12-17
The rotational dynamics of carbon monoxide (CO) in a molten salt, ionic liquids (ILs), and alkanes were investigated by (17)O NMR T1 measurements using labeled C(17)O. The molten salt and the studied ILs have the bis(trifluoromethanesulfonyl)imide anion ([NTf2](-)) in common. In hexane near room temperature, the rotational relaxation times are close to the values predicted from the slip boundary condition in the Stokes-Einstein-Debye (SED) theory. However, in contradiction to the theoretical prediction, the rotational relaxation times decrease as the value of η/T increases, where η and T are the viscosity and absolute temperature, respectively. In other alkanes and ILs used in this study, the rotational relaxation times are much faster than those predicted by SED, and show a unique dependence on the number of alkyl carbons. For the same value of η/T, the CO rotational relaxation times in ILs composed of short-alkyl-chain-length imidazolium cations (1-ethyl-3-methylimidazolium and 1-butyl-3-methylimidazolium) are close to those for a molten salt (Cs[NTf2]). On the other hand, the rotational relaxation times in ILs composed of long-chain-length imidazolium (1-methyl-3-octylimidazolium) and phosphonium (tributylmethylphosphonium and tetraoctylphosphonium) cations are much shorter than the SED predictions. This deviation from theory increases as the alkyl chain length increases. We also found that the rotational relaxation times in dodecane and squalane are similar to those in ILs with a similar number of alkyl carbons. These results are discussed in terms of heterogeneous solvation and in comparison with the translational diffusion of CO in ILs.
Carbon Monoxide Poisoning Cases Autopsied in South Marmara Region
Directory of Open Access Journals (Sweden)
Filiz Eren
2014-10-01
Full Text Available Carbonmonoxide (CO related deaths, which are generally preventable accidents that include accidents due to the coal stoves and water heaters in bath at home, the mining accidents, and other accidents. CO accept as the most common cause of poisoning cases in many countries and its prominent feature is being a colorless, odorless and nonirritant gas. In the period from 2007 until the end of 2011, the autopsy records of the ........ of Turkey were reviewed. Over a period of 5 years a total of 5782 autopsies were done of which 218 involved CO poisoning, constituting 3,8 % of total cases. Information regarding age, sex, month, year, and as well as various aspects were examined. Study data were encoded with computer and Statistical analysis was performed using SPSS for windows program. Of the cases 76 were (34,9% female, 142 were (65,1% male and male/female ratio was 1,9. Of the cases average age was 46.8, range between 1 and 90 years. 57,8% of deaths were in winter markedly. The highest carboxyhemoglobin saturation was 92% in the blood. Poisoning due to CO leaks from coal heaters is an important problem in our country and surrounding regions. The mining accidents should be reduced by increasing safety in the workplace. We must more expend efforts to educate the public and prevent CO poisoning. Key words: Carbon monoxide, poisoning, autopsy.
Hydrogenation of carbon monoxide on Co/MgAl2O4 and Ce-Co/MgAl2O4 catalysts
International Nuclear Information System (INIS)
Kondoh, S.; Muraki, H.; Fujitani
1986-01-01
It is well known that various hydrocarbons are obtained by hydrogenation of CO on Fischer-Tropsch catalysts, the products depending on the catalyst components such as Co, Ni, Fe and Ru: and the reaction conditions, particularly, temperature, pressure, space velocity and H 2 /CO ratio. Further, both reactivity and selectivity of catalysts may be improved by suitable selection of support and an additive. The main program of the present work is to develop a catalyst for producing C 5 + liquid hydrocarbons, as an automobile fuel, by the Fischer-Tropsch synthesis. The authors have studied unique CO catalyst systems consisting of various supports - such as Al 2 O 3 (γ, β, α), MgAl 2 O 4 (alumina magnesia spinel), MgO and additives selected from the lanthanoid elements (LE). The composition of spinel-based supports was altered in a range from 28 mol % excess Al 2 O 3 to 28 mol % excess MgO. Particularly, they found that a MgAl 2 O 4 support with 15-18 mol % excess Al 2 O 3 is the most preferable for our purpose and CeO 2 as the additive for Co/spinel catalyst remarkably improves C 5 + yield. Further, it was confirmed that the catalytic activity of Co-base catalysts agree with the oxidation state of Co-oxides on Co and Co-Ce/spinel catalysts. The performance of Co-based catalysts for the production of higher hydrocarbons from syn-gas were described elsewhere. The items described in this report include (a) selection of supports, (b) selection of optimum reaction conditions for Co-Ce/spinel catalyst, (c) redox characteristics of Co-oxides on a spinel surface, and (d) experimental observation of TPD profiles, adsorption capacities and IR spectra relating to adsorbed CO
Sensorineural Hearing Loss following Carbon Monoxide Poisoning
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Joseph P. Pillion
2012-01-01
Full Text Available 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.
Impacts of black carbon and co-pollutant emissions from transportation sector in Mexico City
Zavala, Miguel; Almanza, Victor; Garcia, Agustin; Jazcilevich, Aron; Lei, Wenfang; Molina, Luisa
2016-04-01
Black carbon is one of the most important short-lived climate-forcing agents, which is harmful to human health and also contributes significantly to climate change. Transportation is one of the largest sources of black carbon emissions in many megacities and urban complexes, with diesel vehicles leading the way. Both on-road and off-road vehicles can emit substantial amounts of harmful BC-containing particulate matter (PM) and are also responsible for large emissions of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), and many other co-emitted volatile organic compounds (VOCs). Regionally, black carbon emissions contributions from mobile sources may vary widely depending on the technical characteristics of the vehicle fleet, the quality and chemical properties of the fuels consumed, and the degree of local development and economic activities that foster wider and more frequent or intensive use of vehicles. This presentation will review and assess the emissions of black carbon from the on-road and off-road transportation sector in the Mexico City Metropolitan Area. Viable mitigation strategies, including innovative technological alternatives to reduce black carbon and co-pollutants in diesel vehicles and their impacts on climate, human health and ecosystems will be described.
Fang, Cong; Luo, Jianmin; Jin, Chengbin; Yuan, Huadong; Sheng, Ouwei; Huang, Hui; Gan, Yongping; Xia, Yang; Liang, Chu; Zhang, Jun; Zhang, Wenkui; Tao, Xinyong
2018-05-23
The metal-CO 2 batteries, especially Na-CO 2 , batteries come into sight owing to their high energy density, ability for CO 2 capture, and the abundance of sodium resource. Besides the sluggish electrochemical reactions at the gas cathodes and the instability of the electrolyte at a high voltage, the final discharge product Na 2 CO 3 is a solid and poor conductor of electricity, which may cause the high overpotential and poor cycle performance for the Na-CO 2 batteries. The promotion of decomposition of Na 2 CO 3 should be an efficient strategy to enhance the electrochemical performance. Here, we design a facile Na 2 CO 3 activation experiment to screen the efficient cathode catalyst for the Na-CO 2 batteries. It is found that the Co 2 MnO x nanowire-decorated carbon fibers (CMO@CF) can promote the Na 2 CO 3 decomposition at the lowest voltage among all these metal oxide-decorated carbon fiber structures. After assembling the Na-CO 2 batteries, the electrodes based on CMO@CF show lower overpotential and better cycling performance compared with the electrodes based on pristine carbon fibers and other metal oxide-modified carbon fibers. We believe this catalyst screening method and the freestanding structure of the CMO@CF electrode may provide an important reference for the development of advanced Na-CO 2 batteries.
Cornforth; Rabovitser; Ahuja; Wagner; Hanson; Cummings; Chudnovsky
1998-01-19
Carbon monoxide (CO) and total nitrogen oxide (NO(x)()) levels were monitored during meat cookery with a standard Ovenpak and a new ultralow-NO(x)() (ULN) cyclonic gas burner. With the standard burner, CO varied from 103 to 152 ppm, NO(x)() was 1.3-10.7 ppm, and surface pinking was observed on both beef and turkey. The ULN burner at optimal efficiency produced only 6.7 ppm of CO and 1 ppm of NO(x)(), insufficient to cause surface pinking. To determine the relative contribution of CO and NO(x)() to pinking, trials were also conducted in an electric oven with various pure gases. Pinking was not observed with up to 149 ppm of CO or 5 ppm of NO. However, as little as 0.4 ppm of nitrogen dioxide (NO(2)) caused pinking of turkey rolls. Beef roasts were pink at >2.5 ppm of NO(2). Thus, pinking previously attributed to CO and NO in gas ovens is instead due to NO(2), which has much greater reactivity than NO with moisture at meat surfaces.
Directory of Open Access Journals (Sweden)
Mehmet Kenan KANBUROGLU
2014-09-01
Full Text Available SUMMARY: Differential diagnosis of primary headache disorders can be challenging for physicians. Although the association of headache with acute carbon monoxide intoxication is very well-defined, in refractory nonspecific headaches associated with chronic low dose exposure to carbon monoxide, CO intoxication is usually overlooked, mostly due to vague symptoms. Herein we present a 15-year-old female patient with chronic carbon monoxide poisoning who was undergoing two years of follow-up care for migraines. Chronic carbon monoxide intoxication may mimic the episodic nature and familial predisposition of migraine attacks. Normal carboxyhemoglobin levels do not exclude the diagnosis, and smoking is a confounding factor. In emergency rooms, patients presenting with headaches had higher levels of carboxyhemoglobin, but, as far as we know, there have been no studies investigating carboxyhemoglobin levels in migraine patients. Chronic carbon monoxide poisoning should be suspected in migraine patients, especially if the attacks occur during winter months. ÖZET: Primer baş ağrısında ayırıcı tanının yapılması bazen doktorlar açısından zor olabilmektedir. Literatürde karbon monoksit ile baş ağrısı arasındaki ilişki çok iyi ortaya konulmuş olmasına karşın, dirençli ve nonspesifik başağrısı nedenlerinden biri olan kronik düşük doz karbon monoksit maruziyeti kendine özgü bulgusu olmadığından sıklıkla atlanmaktadır. Bu yazıda, iki yıl migren tanısı ile takip ve tedavi edilen kronik karbon monoksit zehirlenmesi olan bir olgu sunuldu. Kronik karbon monoksit zehirlenmesi epizodik paterni ve aile fertlerinde benzer şikayetlerin olması nedeniyle migren ataklarını andırabilmektedir. Karboksihemoglobin konsantrasyonlarının normal saptanması tanıyı ekarte ettirmemekte, ayrıca sigara kullanımı da karıştırıcı bir faktör olabilmektedir. Acil servislerine baş ağrısı ile başvuran hastalar
Liu, Chenglong; Zhang, Yimin; Yang, Xiaoyin; Liang, Rongrong; Mao, Yanwei; Hou, Xu; Lu, Xiao; Luo, Xin
2014-06-01
The objectives were to compare the effects of packaging methods on color stability, metmyoglobin-reducing-activity (MRA), total-reducing-activity and NADH concentration of different bovine muscles and to explore potential mechanisms in the enhanced color stability by carbon monoxide modified atmosphere packaging (CO-MAP, 0.4% CO/30% CO2/69.6% N2). Steaks from longissimus lumborum (LL), psoas major (PM) and longissimus thoracis (LT) packaged in CO-MAP, high-oxygen modified atmosphere packaging (HiOx-MAP, 80% O2/20% CO2) or vacuum packaging were stored for 0day, 4days, 9days, and 14days or stored for 9days then displayed in air for 0day, 1day, or 3days. The CO-MAP significantly increased red color stability of all muscles, and especially for PM. The PM and LT were more red than LL in CO-MAP, whereas PM had lowest redness in HiOx-MAP. The content of MetMb in CO-MAP was lower than in HiOx-MAP. Steaks in CO-MAP maintained a higher MRA compared with those in HiOx-MAP during storage. After opening packages, the red color of steaks in CO-MAP deteriorated more slowly compared with that of steaks in HiOx-MAP. Copyright © 2014 Elsevier Ltd. All rights reserved.
Acute carbon monoxide intoxication : the relation between MR findings and clinical outcome
International Nuclear Information System (INIS)
Chang, Jin Bae; Jeong, Hae Woong; Kim, Ki Nam; Kim, Dong Wook; Kim, Chang Soo
1999-01-01
To analyse MR findings of various involving sites and the relation between such findings and clinical outcome, the authors retrospectively reviewed MR images of acute carbon monoxide intoxication. In 12 patients, MR images obtained from several hours to 12 days after acute carbon monoxide intoxication were reviewed. The images were analysed with regard to involved sites, symmetricity, signal intensity, and the presence or absence of hemorrhage, and the relationship between MR findings and clinical outcome; the presence of delayed encephalopathy was then determined. The globus pallidus(n=9), white matter(n=3), [centrum semiovale(n=2), periventricular white matter(n=1)] and gyrus(n=6) [inferior temporal gyrus(n=2), cingulate gyrus(n=1), precentral gyrus(n=1), hippocampal gyrus(n=1), parahippocampal gyrus(n=1)] were typically involved, and there was also involvenent of the corpus callosum(n=3), thalamus(n=2) and midbrain(n=2). All lesions of the globus pallidus, thalamus, midbrain and temporal lobe were bilaterally symmetric. In all these cases, subtle or prominent low signal intensity was seen on spin-echo T1WI, and high signal intensity on PDWI and T2WI. Some lesions of the globus pallidus(n=1), thalamus(n=1) and midbrain(n=1) were associated with hemorrhage, which occurred during the early subacute stage and was seen on high/low signal intensity T1/T2WI images. Acute cerebral(n=1) and cerebellar(n=1) infarctions were also seen. Cerebral white matter involvement correlated with poor clinical outcome, and in two cases, delayed encephalopathy developed. In these cases of acute carbon monoxide intoxication, the globus pallidus, white matter, cortex and hippocampus were frequently involved, and there was also involvement of various sites such as the corpus callosum, thalamus and midbrain. Lesions of the temporal lobe, thalamus and midbrain were bilaterally symmetric. The involvement of cerebral white matter and the presence of delayed encephalopathy can influence
Feddern, Vivian; Cunha Junior, Anildo; De Prá, Marina C; Busi da Silva, Marcio L; Nicoloso, Rodrigo da S; Higarashi, Martha M; Coldebella, Arlei; de Abreu, Paulo G
2017-07-01
The effects of two alternative sources of animal fat-derived biodiesel feedstock on CO 2 , CO, NO x tailpipe emissions as well as fuel consumption were investigated. Biodiesel blends were produced from chicken and swine fat waste (FW-1) or floating fat (FW-2) collected from slaughterhouse wastewater treatment processes. Tests were conducted in an unmodified stationary diesel engine operating under idling conditions in attempt to simulate slow traffic in urban areas. Significant reductions in CO (up to 47% for B100; FW-2) and NO x (up to 20% for B5; FW-2 or B100; FW-1) were attained when using biodiesel fuels at the expense of 5% increase in fuel consumption. Principal component analysis (PCA) was performed to elucidate possible associations among gas (CO 2 , CO, and NO x ) emissions, cetane number and iodine index with different sources of feedstock typically employed in the biodiesel industry. NO x , cetane number and iodine index were inversely proportional to CO 2 and biodiesel concentration. High NO x emissions were reported from high iodine index biodiesel derived especially from forestry, fishery and some agriculture feedstocks, while the biodiesel derived from animal sources consistently presented lower iodine index mitigating NO x emissions. The obtained results point out the applicability of biodiesel fuels derived from fat-rich residues originated from animal production on mitigation of greenhouse gas emissions. The information may encourage practitioners from biodiesel industry whilst contributing towards development of sustainable animal production. Emissions from motor vehicles can contribute considerably to the levels of greenhouse gases in the atmosphere. The use of biodiesel to replace or augment diesel can not only decrease our dependency on fossil fuels but also help decrease air pollution. Thus, different sources of feedstocks are constantly being explored for affordable biodiesel production. However, the amount of carbon monoxide (CO), carbon
Reductive coupling of carbon monoxide to C sub 2 products
Energy Technology Data Exchange (ETDEWEB)
Templeton, J.L.
1991-08-01
We first prepared Tp{prime}(CO){sub 2}W{equivalent to}CH from a conversion of the cationic phosphonium carbyne Tp{prime}(CO){sub 2}W{equivalent to}CPMe{sub 3}+ to a neutral carbene by hydride addition at carbon. Removal of PMe{sub 3} with a Lewis acid trap yielded milligram quantities of the desired terminal carbyne. More recently we have prepared a silylcarbyne precursor which reacts with Bu{sub 4}NF in wet THF to form substantial amounts of the CH carbyne. Dimerization to form an unusual vinylidene bridged complex is a facile decomposition route which consumes the Tp{prime}(CO){sub 2}M{equivalent to}CH monometer for both M=MO and M=W,. Preparation of other carbyne complexes has been achieved using Tp{prime}(CO){sub 2}W{equivalent to}C-Cl as a reagent. Another carbyne derivative was synthesized from Tp{prime}(CO){sub 2}M{equivalent to}C-Cl by adding K(CpFe(Co){sub 2}) to displace the chloride. Organometallic products formed from the reaction of an electrophilic iron carbene complex with nitrosoarenes or azobenzene reflect net insertion of the ArN-X moiety into the Fe=CHAr bond. Cp(CO){sub 2}Fe-O-N(Ar{prime})=CHAr+ and Cp(CO){sub 2}FeN(Ph)-N(Pha)=CHAr+ have been isolated and spectroscopically characterized. More promising results for long term progress in building electrophilic nitrene complexes have been achieved with Group VI reagents. Simple methods for generating Tp{prime}(CO){sub 2}W=NHR for R= Ar and Bu{sup t} are encouraging. Furthermore, removal of H{sup minus} from the amido ligand with either I{sub 2} or (Ph{sub 3}C)(BF{sub 4}) provides access to cationic nitrene complexes.
Creswell, Paul D; Vogt, Christy M; Wozniak, Ryan J; Camponeschi, Jenny; Werner, Mark A; Meiman, Jonathan G
In December 2014, the largest carbon monoxide (CO) poisoning in Wisconsin's history occurred at an ice arena. Following this event, the Wisconsin Environmental Public Health Tracking (WI EPHT) Program sought to improve outreach and surveillance efforts. WI EPHT designed and distributed educational materials on CO poisoning prevention and surveyed stakeholders to gauge the effectiveness of outreach efforts. To enhance surveillance, WI EPHT utilized data from the Wisconsin Poison Center (WPC) to generate real-time alerts of anomalous numbers of CO-related calls. WI EPHT found that 42% of stakeholders reviewed the outreach materials, and 1 ice arena had installed a CO detector as a result. CO alerts were developed using WPC data and are now routinely used in statewide public health surveillance. WI EPHT staff improved CO poisoning prevention outreach and saw a positive response among stakeholders. This work demonstrates ways that health agencies can improve outreach and surveillance for CO poisoning. Improvements in these areas can bolster public health response and may prevent CO-related illness and injury.
Anthropogenic emissions and space-borne observations of carbon monoxide over South Asia
Ul-Haq, Zia; Tariq, Salman; Ali, Muhammad
2016-11-01
The focus of this study is to understand anthropogenic emissions, spatiotemporal variability and trends of carbon monoxide (CO) over South Asia by using datasets from MACCity (Monitoring Atmospheric Composition and Climate, MACC and megaCITY - Zoom for the Environment, CityZEN), REAS (Regional Emission inventory in Asia), AIRS (Atmospheric Infrared Sounder) and SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY). MACCity anthropogenic emissions show an overall increase of 16.5% during 2000-2010. Elevated levels of MACCity CO are found in Indo-Gangetic Basin (IGB), eastern mining region of India, Bangladesh and large urban areas. Some of the major contributors of these emissions have been identified as agricultural waste burning, land transport, industrial production, and energy generation and distribution. An area averaged mean value of AIRS CO at 600 hPa is found to be 114 ± 2 ppbv (slope -0.48 ± 0.2 ppbv yr-1, y-intercept 117 ± 1 ppbv and r = 0.68) with a minor declining trend at -0.41 ± 0.18% yr-1 over the region during 2003-2015. A strong seasonality in AIRS CO concentration is observed with spring season peak in March 129 ± 1.9 ppbv, whereas low values have been observed in summer monsoon with sturdy dip in July 99.6 ± 1.94 ppbv. AIRS CO and SCIAMACHY CO Total Column (CO TC) over the study region show spatial patterns similar to MACCity and REAS emissions. An analysis of SCIAMACHY CO TC tendencies has been performed which indicates minor rising trends over some parts of the region. Background CO, Recent Emissions (RE), and spatial anomalies in RE over high anthropogenic activity zones of Indus Basin, Ganges Basin and Eastern Region were analyzed using AIRS and SCIAMACHY CO data.
Carbonation and CO2 uptake of concrete
International Nuclear Information System (INIS)
Yang, Keun-Hyeok; Seo, Eun-A; Tae, Sung-Ho
2014-01-01
This study developed a reliable procedure to assess the carbon dioxide (CO 2 ) uptake of concrete by carbonation during the service life of a structure and by the recycling of concrete after demolition. To generalize the amount of absorbable CO 2 per unit volume of concrete, the molar concentration of carbonatable constituents in hardened cement paste was simplified as a function of the unit content of cement, and the degree of hydration of the cement paste was formulated as a function of the water-to-cement ratio. The contribution of the relative humidity, type of finishing material for the concrete surface, and the substitution level of supplementary cementitious materials to the CO 2 diffusion coefficient in concrete was reflected using various correction factors. The following parameters varying with the recycling scenario were also considered: the carbonatable surface area of concrete crusher-runs and underground phenomena of the decreased CO 2 diffusion coefficient and increased CO 2 concentration. Based on the developed procedure, a case study was conducted for an apartment building with a principal wall system and an office building with a Rahmen system, with the aim of examining the CO 2 uptake of each structural element under different exposure environments during the service life and recycling of the building. As input data necessary for the case study, data collected from actual surveys conducted in 2012 in South Korea were used, which included data on the surrounding environments, lifecycle inventory database, life expectancy of structures, and recycling activity scenario. Ultimately, the CO 2 uptake of concrete during a 100-year lifecycle (life expectancy of 40 years and recycling span of 60 years) was estimated to be 15.5%–17% of the CO 2 emissions from concrete production, which roughly corresponds to 18%–21% of the CO 2 emissions from the production of ordinary Portland cement. - Highlights: • CO 2 uptake assessment approach owing to the
International Nuclear Information System (INIS)
Chien, Peter Tzu-Yu; Lin, Chih-Chung; Hsiao, Li-Der; Yang, Chuen-Mao
2015-01-01
Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE 2 release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression and cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2-induced HO-1
Energy Technology Data Exchange (ETDEWEB)
Chien, Peter Tzu-Yu [Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Lin, Chih-Chung; Hsiao, Li-Der [Department of Anesthetics, Chang Gung Memorial Hospital at Lin-Kou and College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Yang, Chuen-Mao, E-mail: chuenmao@mail.cgu.edu.tw [Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Research Center for Industry of Human Ecology and Graduate Institute of Health Industry Technology, Chang Gung University of Science and Technology, Tao-Yuan, Taiwan (China)
2015-12-01
Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE{sub 2} release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression and cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2-induced HO
International Nuclear Information System (INIS)
Choi, V.W.Y.; Wong, M.Y.P.; Cheng, S.H.; Yu, K.N.
2012-01-01
In the present work, the influence of a low concentration of exogenous carbon monoxide (CO) liberated from tricarbonylchloro(glycinato)ruthenium (II) (CORM-3) on the radiation induced bystander effect (RIBE) in vivo between embryos of the zebrafish was studied. RIBE was assessed through the number of apoptotic signals revealed on embryos at 25 h post fertilization (hpf). A significant attenuation of apoptosis on the bystander embryos induced by RIBE in a CO concentration dependent manner was observed. - Highlights: ► RIBE between zebrafish embryos in vivo was assessed by the level of apoptosis. ► CO from 10 and 20 μM CORM-3 entirely suppressed the RIBE. ► CO from 5 μM CORM-3 significantly attenuated the level of apoptosis. ► Inactive CORM-3 did not lead to suppression of RIBE. ► Suppression of RIBE by CO depended on the concentration of CORM-3.
How much CO2 is trapped in carbonate minerals of a natural CO2 occurrence?
Király, Csilla; Szabó, Zsuzsanna; Szamosfalvi, Ágnes; Cseresznyés, Dóra; Király, Edit; Szabó, Csaba; Falus, György
2017-04-01
Carbon Capture and Storage (CCS) is a transitional technology to decrease CO2 emissions from human fossil fuel usage and, therefore, to mitigate climate change. The most important criteria of a CO2 geological storage reservoir is that it must hold the injected CO2 for geological time scales without its significant seepage. The injected CO2 undergoes physical and chemical reactions in the reservoir rocks such as structural-stratigraphic, residual, dissolution or mineral trapping mechanisms. Among these, the safest is the mineral trapping, when carbonate minerals such as calcite, ankerite, siderite, dolomite and dawsonite build the CO2 into their crystal structures. The study of natural CO2 occurrences may help to understand the processes in CO2 reservoirs on geological time scales. This is the reason why the selected, the Mihályi-Répcelak natural CO2 occurrence as our research area, which is able to provide particular and highly significant information for the future of CO2 storage. The area is one of the best known CO2 fields in Central Europe. The main aim of this study is to estimate the amount of CO2 trapped in the mineral phase at Mihályi-Répcelak CO2 reservoirs. For gaining the suitable data, we apply petrographic, major and trace element (microprobe and LA-ICP-MS) and stable isotope analysis (mass spectrometry) and thermodynamic and kinetic geochemical models coded in PHREEQC. Rock and pore water compositions of the same formation, representing the pre-CO2 flooding stages of the Mihályi-Répcelak natural CO2 reservoirs are used in the models. Kinetic rate parameters are derived from the USGS report of Palandri and Kharaka (2004). The results of petrographic analysis show that a significant amount of dawsonite (NaAlCO3(OH)2, max. 16 m/m%) precipitated in the rock due to its reactions with CO2 which flooded the reservoir. This carbonate mineral alone traps about 10-30 kg/m3 of the reservoir rock from the CO2 at Mihályi-Répcelak area, which is an
Carbon Dioxide (CO2) in Blood: MedlinePlus Lab Test Information
... this page: https://medlineplus.gov/labtests/carbondioxideco2inblood.html Carbon Dioxide (CO2) in Blood To use the sharing features ... this page, please enable JavaScript. What is a Carbon Dioxide (CO2) Blood Test? Carbon dioxide (CO2) is an ...
International Nuclear Information System (INIS)
Yver, C.; Schmidt, M.; Bousquet, P.; Ramonet, M.; Bousquet, P.; Zahorowski, W.
2009-01-01
Since June 2006, simultaneous semicontinuous measurements of tropospheric molecular hydrogen (H 2 ), carbon monoxide (CO), and radon-222 ( 222 Rn) have been performed at Gif-sur-Yvette (Paris region), a suburban atmospheric measurement site in France. Molecular hydrogen mixing ratios range from 500 to 1000 ppb, CO mixing ratios vary from 100 to 1400 ppb, and 222 Rn concentrations fluctuate from 0 to 20 Bq m -3 . The H 2 seasonal cycle shows the expected pattern for the Northern Hemisphere with a maximum in spring and a minimum in autumn. We inferred a mean baseline value of 533 ppb with a peak-to-peak amplitude of 30 ppb. Carbon monoxide exhibits a seasonal cycle with a maximum in winter and a minimum in summer. The mean baseline value reaches 132 ppb with a peak-to-peak amplitude of 40 ppb. Radon-222 presents weak seasonal variations with a maximum in autumn/winter and a minimum in spring/summer. The diurnal cycles of H 2 and CO are dominated by emissions from nearby traffic with two peaks during morning and evening rush hours. The typical H 2 /CO emission ratio from traffic is found to be 0.47 ± 0.08 on a molar basis (ppb/ppb). The radon tracer method is applied to nighttime H 2 observations to estimate the H 2 soil uptake of the nocturnal catchment area of our sampling site. The influences from nocturnal local anthropogenic combustion sources are estimated by parallel measurements of CO at 0.14 * 10 -5 g(H 2 ) m -2 h -1 . The mean inferred dry deposition velocity is 0.024 ± 0.013 cm s -1 with a seasonal amplitude of 40% at Gif-sur-Yvette.
Subhashish Dey; Ganesh Chandra Dhal; Devendra Mohan; Ram Prasad
2017-01-01
Carbon monoxide (CO) is a poisonous gas, recognized as a silent killer. The gas is produced by incomplete combustion of carbonaceous fuel. Recent studies have shown that hopcalite group is one of the promising catalysts for CO oxidation at low temperature. In this study, hopcalite (CuMnOx) catalysts were prepared by KMnO4 co-precipitation method followed by washing, drying the precipitate at different temperatures (22, 50, 90, 110, and 120 oC) for 12 h in an oven and subsequent calcination at...
Directory of Open Access Journals (Sweden)
F. L. Herron-Thorpe
2012-06-01
Full Text Available Results from a regional air quality forecast model, AIRPACT-3, were compared to AIRS carbon monoxide column densities for the spring of 2010 over the Pacific Northwest. AIRPACT-3 column densities showed high correlation (R > 0.9 but were significantly biased (~25% with consistent under-predictions for spring months when there is significant transport from Asia. The AIRPACT-3 CO bias relative to AIRS was eliminated by incorporating dynamic boundary conditions derived from NCAR's MOZART forecasts with assimilated MOPITT carbon monoxide. Changes in ozone-related boundary conditions derived from MOZART forecasts are also discussed and found to affect background levels by ± 10 ppb but not found to significantly affect peak ozone surface concentrations.
Atmospheric CO2 measurements reveal strong drought sensitivity of Amazonian carbon balance
Miller, J. B.; Gatti, L.; Gloor, M.; Doughty, C.; Malhi, Y.; Domingues, L. G.; Basso, L. S.; Martinewski, A.; Correia, C.; Borges, V.; Freitas, S. R.; Braz, R.; Anderson, L.; Rocha, H.; Grace, J.; Phillips, O.; Lloyd, J.
2013-12-01
Potential feedbacks between land carbon pools and climate are one of the largest sources of uncertainty for predicting future global climate, but estimates of their sensitivity to climate anomalies in the tropics and determination of underlying mechanisms are either incomplete or strongly model-based. Amazonia alone stores ~150-200 Pg of labile carbon, and has experienced an increasing trend in temperature and extreme floods and droughts over the last two decades. Here we report the first Amazon Basin-wide seasonal and annual carbon balances based on tropospheric greenhouse gas sampling, during an anomalously dry and a wet year, 2010 and 2011, providing the first whole-system assessment of sensitivity to such conditions. During 2010, the Amazon Basin lost 0.5×0.2 PgCyr-1 while in 2011 it was approximately carbon neutral (0.06×0.1 PgCyr-1). Carbon loss via fire was 0.5×0.1 PgCyr-1 in 2010 and 0.3×0.1 PgCyr-1 in 2011, as derived from Basin-wide carbon monoxide (CO) enhancements. Subtracting fire emissions from total carbon flux to derive Basin net biome exchange (NBE) reveals that in 2010 the non-fire regions of the Basin were carbon neutral; in 2011 they were a net carbon sink of -0.3×0.1 PgC yr-1, roughly consistent with a three-decade long intact-forest biomass sink of ~ -0.5×0.3 PgCyr-1 estimated from forest censuses. Altogether, our results suggest that if the recent trend of precipitation extremes persists, the Amazon region may become an increasing carbon source as a result of both emissions from fires and suppression of NBE by drought.
Chlorination of niobium oxide in the presence of carbon monoxide
International Nuclear Information System (INIS)
Freitas, L.R. de
1984-01-01
The chlorination kinetics of niobium pentoxide in the presence of carbon monoxide between 500-800 0 C of temperature is studied. The following variable that influences on the reaction rate are analysed: gas flow, geometry and volume of the Nb 2 O 5 samples, reaction temperature and composition of the chlorinated mixture. At the same time, two other materials were studied: the CaO.Nb 2 O 5 (synthetized in laboratory) and pyrochlorine concentrates. The three materials are compared for the chlorination method used. (M.A.C.) [pt
Xu, Ruina; Li, Rong; Ma, Jin; He, Di; Jiang, Peixue
2017-09-19
Geological carbon sequestration (GCS) in deep saline aquifers is an effective means for storing carbon dioxide to address global climate change. As the time after injection increases, the safety of storage increases as the CO 2 transforms from a separate phase to CO 2 (aq) and HCO 3 - by dissolution and then to carbonates by mineral dissolution. However, subsequent depressurization could lead to dissolved CO 2 (aq) escaping from the formation water and creating a new separate phase which may reduce the GCS system safety. The mineral dissolution and the CO 2 exsolution and mineral precipitation during depressurization change the morphology, porosity, and permeability of the porous rock medium, which then affects the two-phase flow of the CO 2 and formation water. A better understanding of these effects on the CO 2 -water two-phase flow will improve predictions of the long-term CO 2 storage reliability, especially the impact of depressurization on the long-term stability. In this Account, we summarize our recent work on the effect of CO 2 exsolution and mineral dissolution/precipitation on CO 2 transport in GCS reservoirs. We place emphasis on understanding the behavior and transformation of the carbon components in the reservoir, including CO 2 (sc/g), CO 2 (aq), HCO 3 - , and