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Sample records for monoxide diffusing capacity

  1. Placental diffusing capacities at varied carbon monoxide tensions.

    PubMed Central

    Bissonnette, J M; Wickham, W K; Drummond, W H

    1977-01-01

    To test the hypothesis that carbon monoxide transfer across the placenta is, in part, a facilitated process, we have looked for evidence of saturation kinetics for carbon monoxide. In eight pregnant ewes, fetal to maternal carbon monoxide transfer was examined in a preparation in which the fetal side of the placenta was perfused with blood. The carboxyhemoglobin concentrations on the fetal side of the placenta were varied from 4.8 to 70% in 23 measurements. At increased carbon monoxide tensions, the transfer from fetus to mother always decreased. The slope of log rate of carbon monoxide transfer vs. log partial pressure gradient across the placenta was significantly different from 1. Placental membrane diffusing capacity was calculated separately from total placental diffusing capacity which includes hemoglobin reaction rates and erythrocyte membrane diffusion. Placental membrane diffusing capacity decreased at increased carbon monoxide tensions. Placental permeability for urea did not change with increasing carbon monoxide tensions. These results are consistent with the hypothesis that carbon monoxide diffusion in the placenta is, in part, carrier mediated. PMID:864001

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

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

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

  3. Predicting diffusive alveolar oxygen transfer from carbon monoxide-diffusing capacity in exercising foxhounds

    PubMed Central

    Hsia, Connie C. W.; Wagner, Peter D.; Dane, D. Merrill; Wagner, Harrieth E.; Johnson, Robert L.

    2008-01-01

    Although lung diffusing capacity for carbon monoxide (DlCO) is a widely used test of diffusive O2 transfer, few studies have directly related DlCO to O2-diffusing capacity (DlO2); none has used the components of DlCO, i.e., conductance of alveolar membrane and capillary blood, to predict DlO2 from rest to exercise. To understand the relationship between DlCO and DlO2 at matched levels of cardiac output, we analyzed cumulative data from rest to heavy exercise in 43 adult dogs, with normal lungs or reduced lung capacity following lung resection, that were studied by two techniques. 1) A rebreathing (RB) technique was used to measure DlCO and pulmonary blood flow at two O2 tensions, independent of O2 exchange. DlCO was partitioned into CO-diffusing capacity of alveolar membrane and pulmonary capillary blood volume using the Roughton-Forster equation and converted into an equivalent DlO2, [DlO2(RB)]. 2) A multiple inert-gas elimination technique (MIGET) was used to measure ventilation-perfusion distributions, O2 and CO2 exchange under hypoxia, to derive DlO2 [DlO2(MIGET)] by the Lilienthal-Riley technique and Bohr integration. For direct comparisons, DlO2(RB) was interpolated to the cardiac output measured by the Fick principle corresponding to DlO2(MIGET). The DlO2-to-DlCO ratio averaged 1.61. Correlation between DlO2(RB) and DlO2(MIGET) was similar in normal and post-resection groups. Overall, DlO2(MIGET) = 0.975 DlO2(RB); mean difference between the two techniques was under 5% for both animal groups. We conclude that, despite various uncertainties inherent in these two disparate methods, the Roughton-Forster equation adequately predicts diffusive O2 transfer from rest to heavy exercise in canines with normal, as well as reduced, lung capacities. PMID:18719238

  4. A simultaneous single breath measurement of pulmonary diffusing capacity with nitric oxide and carbon monoxide.

    PubMed

    Borland, C D; Higenbottam, T W

    1989-01-01

    Pulmonary diffusing capacity (DL) for carbon monoxide (CO) and nitric oxide (NO) were simultaneously measured in man using the single breath method, by adding 4O ppm of NO to the inspired gas and analysing the expirate for NO by a chemiluminescent method. The mean ratio of DLNO to DLCO in thirteen subjects was 4.3 (SD 0.3), mean DLNO = 49 mmol.min-1.kPa-1 (SD 10) and mean DLCO = 11 mmol.min-1.kPa-1 (SD 2). An increase in alveolar oxygen concentration from a mean of 18 to 68% in five subjects was associated with a 54% fall in DLCO but no change in DLNO. A reduction of lung volume from total lung capacity (TLC) (mean of 7 l) to a mean volume of 3.9 l in five subjects caused a fall in both DLNO (by 34%) and DLCO (by 8%). With 175 watts cycle exercise in three subjects the DLCO rose by 45% and DLNO by 25%. Since NO reacts much faster with haemoglobin than CO, DLNO should be influenced much less by reaction with haemoglobin, and perhaps represents a better index for the diffusing capacity of the alveolar-capillary membrane (Dm) than DLCO.

  5. Effect of varying alveolar oxygen partial pressure on diffusing capacity for nitric oxide and carbon monoxide, membrane diffusing capacity and lung capillary blood volume.

    PubMed

    Borland, C D; Cox, Y

    1991-12-01

    1. To examine the effect of varying oxygen partial pressure (PAO2) on nitric oxide (DLNO) and carbon monoxide (DLCO) diffusing capacity (transfer factor), 10 subjects performed combined DLCO/DLNO measurements with the inspired mixture made up with three different oxygen concentrations (25%, 18% and 15%) to give PAO2 values of 12-20 kPa. 2. A novel method is described for calculating membrane diffusing capacity (DM) and pulmonary capillary volume (Qc) from DLNO and DLCO. 3. The mean DMCO was 52.89 mmol min-1 kPa-1 and Qc was 0.056 litre. Reducing PAO2 from 20 to 12 kPa resulted in an increase in DLCO = -0.124 (O2%) + 11.67 (P less than 0.001) and a fall in DLNO = 0.538 (O2%) + 32.01 (P less than 0.001) and a fall in DLNO/DLCO = 0.107 (O2%) + 2.52 (P less than 0.001). DM (P = 0.59) and Qc (P = 0.64) also tended to fall with falling PAO2. 4. It appears more likely that the minor reduction in DLNO that we have observed with falling PAO2 is due to diffusion rather than reaction limitation.

  6. Historical review: the carbon monoxide diffusing capacity (DLCO) and its membrane (DM) and red cell (Theta.Vc) components.

    PubMed

    Hughes, J M B; Bates, D V

    2003-11-14

    The single breath carbon monoxide diffusing capacity (DLCO sb), also called the transfer factor (TLCO), was introduced by Marie and August Krogh in two papers (Krogh and Krogh, Skand. Arch. Physiol. 23, 236-247, 1909; Krogh, J. Physiol., Lond. 49, 271-296, 1915). Physiologically, their measurements showed that sufficient oxygen (by extrapolation from CO) diffused passively from gas to blood without the need to postulate oxygen secretion, a popular theory at the time. Their DLCO sb technique was neglected until the advent of the infra-red CO meter in the 1950s. Ogilvie et al., J. Clin. Invest. 36, 1-17, 1957 published a standardized technique for a 'modified Krogh' single breath DLCO, which eventually became the method of choice in pulmonary function laboratories. The Roughton-Forster equation (J. Appl. Physiol. 1957, 11, 290-302) was an important step conceptually; it partitioned alveolar-capillary diffusion of oxygen (O2) and carbon monoxide (CO) into a membrane component (DM) and a red cell component (theta.Vc) where theta is the DLCO (or DL(O2)) per ml of blood (measured in vitro), and Vc is the pulmonary capillary volume. This equation was based on the kinetics of O2 and CO with haemoglobin (Hb) in solution and with whole blood Hartridge and Roughton, Nature, 1923, 111, 325-326; Proc. R. Soc. Lond. Ser. A, 1923, 104, 376-394; (Proc. R. Soc. Lond. Ser. B, 1923, 94, 336-367; Proc. R. Soc. Lond. Ser. A 1923, 104, 395-430; J. Physiol., Lond. 1927, 62, 232-242; Roughton, Proc. R. Soc. Lond. Ser. B 1932, 111, 1-36) and on the relationship between alveolar P(O2) and 1/DLCO. Subsequently, the relationship between DL(O2) (Lilienthal et al., Am. J. Physiol. 147, 199-216, 1946) and DL(CO) was defined. More recently, the measurement of the nitric oxide diffusing capacity (DLNO) has been introduced. For DL(O2) and DLNO the membrane component (as 1/DM) is an important part of the overall diffusion (transfer) resistance. For the DLCO, 1/theta.Vc probably plays the greater

  7. Pulmonary diffusing capacities for nitric oxide and carbon monoxide determined by rebreathing in dogs.

    PubMed

    Meyer, M; Schuster, K D; Schulz, H; Mohr, M; Piiper, J

    1990-06-01

    Pulmonary diffusing capacities (DL) of NO and CO were determined simultaneously from rebreathing equilibration kinetics in anesthetized paralyzed supine dogs (mean body wt 20 kg) after denitrogenation (replacement of N2 by Ar). During rebreathing the dogs were ventilated in closed circuit with a gas mixture containing 0.06% NO, 0.06% 13C18O, and 1% He in Ar for 15 s, with tidal volume of 0.5 liter and frequency of 60/min. The partial pressures of NO, 13C18O, 16O18O, N2, Ar, CO2, and He in the trachea were continuously analyzed by mass spectrometry. Measurements were performed at various O2 levels characterized by the mean end-expired PO2 during rebreathing (PE'O2). In control conditions ("normoxia," PE'O2 = 67 +/- 8 Torr) the following mean +/- SD values were obtained (in ml.min-1.Torr-1): DLNO = 52.4 +/- 11.0 and DLCO = 15.4 +/- 2.9. In hypoxia (PE'O2 = 24 +/- 7 Torr) DLNO increased by 11 +/- 8% and DLCO by 19 +/- 10%, and in hyperoxia (PE'O2 = 390 +/- 26 Torr) DLNO decreased to 87 +/- 3% and DLCO to 56 +/- 8% with respect to values in normoxia. DLNO/DLCO of 3.24 +/- 0.06 (hypoxia), 3.38 +/- 0.31 (normoxia), and 5.54 +/- 1.04 (hyperoxia) were significantly higher than the NO/CO Krogh diffusion constant ratio (1.92) predicted for simple diffusion through aqueous layers. With increasing O2 uptake elicited by 2,4-dinitrophenol, DLNO and DLCO increased and DLNO/DLCO remained close to unchanged. The results suggest that the combined effects of diffusion and chemical reaction with hemoglobin limit alveolar-capillary transport of CO. If it is assumed that reaction kinetics of NO with hemoglobin (known to be extremely fast) are not rate limiting for NO uptake, the contribution of the slow chemical reaction with hemoglobin to the total CO uptake resistance (= 1/DLCO) was estimated to be 38% in hypoxia, 41% in normoxia, and 64% in hyperoxia. The various factors expected to restrict the validity of this analysis are discussed, in particular the effects of functional

  8. Lung diffusion capacity for nitric oxide and carbon monoxide is impaired similarly following short-term graded exercise.

    PubMed

    Zavorsky, Gerald S; Lands, Larry C

    2005-02-01

    Study aimed to determine whether short-term graded exercise affects single-breath lung diffusion capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) similarly, and whether the DLNO/DLCO ratios during rest are altered post-exercise compared to pre-exercise. Eleven healthy subjects (age=29+/-6 years; weight=76.6+/-13.2 kg; height=177.9+/-13.2 cm; and maximal oxygen uptake or V(.-)(O(2max) = 52.7 +/- 9.3 ml kg(-1) min(-1))performed simultaneous single-breath DLNO and DLCO measurements at rest (inspired NO concentration=43.2+/-4.1 ppm, inspired CO concentration=0.30%) 15 min before and 2h after a graded exercise test to exhaustion (exercise duration=593+/-135 s). Resting DLNO and DLCO was similarly reduced 2h post-exercise (DLNO=-7.8+/-3.5%, DLCO=-10.3+/-6.9%, and P<0.05) due to reductions in pulmonary capillary blood volume (-11.3+/-9.0%, P<0.05) and membrane diffusing capacity for CO (-7.8+/-3.5%; P<0.05). The change in DLCO was reflected by the change in DLNO post-exercise such that 68% of the variance in the change in DLCO was accounted for by the variance in the change in DLNO (P<0.05). The DLNO/DLCO ratio was not altered post-exercise (5.87+/-0.37) compared to pre-exercise (5.70+/-0.34). We conclude that the decrease in single-breath DLNO and DLCO from pre- to post-exercise is similar, the magnitude of the change in DLCO closely reflects that of the change in DLNO, and single-breath DLNO/DLCO ratios are independent of the timing of measurement suggesting that using NO and CO transfer gases are valid in looking at short-term changes in lung diffusional conductance.

  9. Lung diffusing capacity for nitric oxide and carbon monoxide in relation to morphological changes as assessed by computed tomography in patients with cystic fibrosis

    PubMed Central

    Dressel, Holger; Filser, Laura; Fischer, Rainald; Marten, Katharina; Müller-Lisse, Ullrich; de la Motte, Dorothea; Nowak, Dennis; Huber, Rudolf M; Jörres, Rudolf A

    2009-01-01

    Background Due to large-scale destruction, changes in membrane diffusion (Dm) may occur in cystic fibrosis (CF), in correspondence to alterations observed by computed tomography (CT). Dm can be easily quantified via the diffusing capacity for nitric oxide (DLNO), as opposed to the conventional diffusing capacity for carbon monoxide (DLCO). We thus studied the relationship between DLNO as well as DLCO and a CF-specific CT score in patients with stable CF. Methods Simultaneous single-breath determinations of DLNO and DLCO were performed in 21 CF patients (mean ± SD age 35 ± 9 y, FEV1 66 ± 28%pred). Patients also underwent spirometry and bodyplethysmography. CT scans were evaluated via the Brody score and rank correlations (rS) with z-scores of functional measures were computed. Results CT scores correlated best with DLNO (rS = -0.83; p < 0.001). Scores were also related to the volume-specific NO transfer coefficient (KNO; rS = -0.63; p < 0.01) and to DLCO (rS = -0.79; p < 0.001) but not KCO. Z-scores for DLNO were significantly lower than for DLCO (p < 0.001). Correlations with spirometric (e.g., FEV1, IVC) or bodyplethysmographic (e.g., SRaw, RV/TLC) indices were weaker than for DLNO or DLCO but most of them were also significant (p < 0.05 each). Conclusion In this cross sectional study in patients with CF, DLNO and DLCO reflected CT-morphological alterations of the lung better than other measures. Thus the combined diffusing capacity for NO and CO may play a future role for the non-invasive, functional assessment of structural alterations of the lung in CF. PMID:19531222

  10. Diffusion capacity of the lung for carbon monoxide - A potential marker of impaired gas exchange or of systemic deconditioning in chronic obstructive lung disease?

    PubMed

    Weinreich, Ulla Møller; Thomsen, Lars Pilegaard; Brock, Christina; Karbing, Dan Stieper; Rees, Stephen Edward

    2015-11-01

    Gas exchange impairment is primarily caused by ventilation-perfusion mismatch in chronic obstructive pulmonary disease (COPD), where diffusing capacity of the lungs for carbon monoxide (DLCO) remains the clinical measure. This study investigates whether DLCO: (1) can predict respiratory impairment in COPD, that is, changes in oxygen and carbon dioxide (CO2); (2) is associated with combined risk assessment score for COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) score); and (3) is associated with blood glucose and body mass index (BMI). Fifty patients were included retrospectively. DLCO; arterial blood gas at inspired oxygen (FiO2) = 0.21; oxygen saturation (SpO2) at FiO2 = 0.21 (SpO2 (21)) and FiO2 = 0.15 (SpO2 (15)) were registered. Difference between arterial and end-tidal CO2 (ΔCO2) was calculated. COPD severity was stratified according to GOLD score. The association between DLCO, SpO2, ΔCO2, GOLD score, blood glucose, and BMI was investigated. Multiple regression showed association between DLCO and GOLD score, BMI, and glucose level (R (2) = 0.6, p < 0.0001). Linear and multiple regression showed an association between DLCO and SpO2 (21) (R (2) = 0.3, p = 0.001 and p = 0.03, respectively) without contribution from SpO2 (15) or ΔCO2. A stronger association between DLCO and GOLD score than between DLCO and SpO2 could indicate that DLCO is more descriptive of systemic deconditioning than gas exchange in COPD patients. However, further larger studies are needed. A weaker association is seen between DLCO and SpO2 (21) without contribution from SpO2 (15) and ΔCO2. This could indicate that DLCO is more descriptive of systemic deconditioning than gas exchange in COPD patients. However, further larger studies are needed.

  11. Carbon Monoxide and Soot Formation in Inverse Diffusion Flames

    NASA Technical Reports Server (NTRS)

    Blevins, L. G.; Mulholland, G. W.; Davis, R. W.

    1999-01-01

    The objective of this project is to study carbon monoxide (CO) and soot formation in laminar, inverse diffusion flames (IDFs). The IDF is used because it is a special case of underventilated combustion. The microgravity environment is crucial for this study because buoyancy-induced instabilities impede systematic variation of IDF operating conditions in normal gravity. The project described in this paper is just beginning, and no results are available. Hence, the goals of this paper are to establish the motivation for the research, to review the IDF literature, and to briefly introduce the experimental and computational plan for the research.

  12. Recruitment of lung diffusing capacity: update of concept and application.

    PubMed

    Hsia, Connie C W

    2002-11-01

    Lung diffusing capacity (DL) for carbon monoxide (DLCO), nitric oxide (DLNO) or oxygen (DLO2) increases from rest to peak exercise without reaching an upper limit; this recruitment results from interactions among alveolar volume (VA), and cardiac output (q), as well as changing physical properties and spatial distribution of capillary erythrocytes, and is critical for maintaining a normal arterial oxygen saturation. DLCO and DLNO can be used to interpret the effectiveness of diffusive oxygen transport and track structural alterations of the alveolar-capillary barrier, providing sensitive noninvasive indicators of microvascular integrity in health and disease. Clinical interpretation of DL should take into account Q in addition to VA and hemoglobin concentration.

  13. The rise in carboxyhemoglobin from repeated pulmonary diffusing capacity tests.

    PubMed

    Zavorsky, Gerald S

    2013-03-01

    The purpose of this study determined the rise in carboxyhemoglobin percentage (COHb) from repeated pulmonary diffusing capacity tests using 5 or 10s single breath-hold maneuvers. Five male and four female non-smokers [baseline COHb=1.2 (SD 0.5%)] performed repeated pulmonary diffusing capacity testing on two separate days. The days were randomized to either repeated 10s (0.28% CO), or 5s (0.28% CO, 55ppm NO) breath-hold maneuvers. Twenty-two 5s breath-hold maneuvers, each separated by 4min rest, raised COHb to 11.1 (1.4)% and minimally raised the methemoglobin percentage (METHb) by 0.3 (0.2)% to a value of 0.8 (0.2)%. After the 22nd test, pulmonary diffusing capacity for carbon monoxide (DLCO) was reduced by about 4mL/min/mmHg, equating to a 0.44% increase in COHb per 5s breath-hold maneuver and a concomitant 0.35mL/min/mmHg decrease in DLCO. Pulmonary diffusing capacity for nitric oxide (DLNO) was not altered after 22 tests. On another day, the 10s single breath-hold maneuver increased COHb by 0.64% per test, and reduced DLCO by 0.44mL/min/mmHg per test. In conclusion, 5s breath-hold maneuvers do not appreciably raise METHb or DLNO, and DLCO is only significantly reduced when COHb is at least 6%.

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

    SciTech Connect

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

    1988-12-01

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

  15. An Urban Diffusion Simulation Model for Carbon Monoxide

    ERIC Educational Resources Information Center

    Johnson, W. B.; And Others

    1973-01-01

    A relatively simple Gaussian-type diffusion simulation model for calculating urban carbon (CO) concentrations as a function of local meteorology and the distribution of traffic is described. The model can be used in two ways: in the synoptic mode and in the climatological mode. (Author/BL)

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

    SciTech Connect

    Guo, Hongsheng; Thomson, Kevin A.; Smallwood, Gregory J.

    2009-06-15

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

  17. Pulmonary diffusing capacity after maximal exercise.

    PubMed

    Manier, G; Moinard, J; Stoïcheff, H

    1993-12-01

    To determine the effect of maximal exercise on alveolocapillary membrane diffusing capacity (Dm), 12 professional handball players aged 23.4 +/- 3.3 (SD) yr were studied before and during early recovery from a progressive maximal exercise [immediately (t0), 15 min, and 30 min (t30) after exercise]. Lung capillary blood volume and Dm were determined in a one-step maneuver by simultaneous measurement of CO and NO lung transfer (DLCO and DLNO, respectively) with use of the single-breath breath-hold method. At t0, DLCO was elevated (13.1 +/- 12.0%; P < 0.01) but both DLNO and Dm for CO remained unchanged. Between t0 and t30, both DLCO and DLNO decreased significantly. At t30, DLCO was not different from the control resting value. DLNO (and consequently Dm for CO) was significantly lower than the control value at t30 (-8.9 +/- 8.1%; P < 0.01). Lung capillary blood volume was elevated at t0 (18.0 +/- 19.0%; P < 0.01) but progressively decreased to near control resting values at t30. Differences in the postexercise kinetics of both DLCO and DLNO point to a role of the transient increase in pulmonary vascular recruitment during the recovery period. We concluded that Dm was somewhat decreased in the 30 min after maximal exercise of short duration, but the exact pulmonary mechanisms involved remain to be elucidated.

  18. Pulmonary tissue volume, cardiac output, and diffusing capacity in sustained microgravity

    NASA Technical Reports Server (NTRS)

    Verbanck, S.; Larsson, H.; Linnarsson, D.; Prisk, G. K.; West, J. B.; Paiva, M.

    1997-01-01

    In microgravity (microG) humans have marked changes in body fluids, with a combination of an overall fluid loss and a redistribution of fluids in the cranial direction. We investigated whether interstitial pulmonary edema develops as a result of a headward fluid shift or whether pulmonary tissue fluid volume is reduced as a result of the overall loss of body fluid. We measured pulmonary tissue volume (Vti), capillary blood flow, and diffusing capacity in four subjects before, during, and after 10 days of exposure to microG during spaceflight. Measurements were made by rebreathing a gas mixture containing small amounts of acetylene, carbon monoxide, and argon. Measurements made early in flight in two subjects showed no change in Vti despite large increases in stroke volume (40%) and diffusing capacity (13%) consistent with increased pulmonary capillary blood volume. Late in-flight measurements in four subjects showed a 25% reduction in Vti compared with preflight controls (P < 0.001). There was a concomittant reduction in stroke volume, to the extent that it was no longer significantly different from preflight control. Diffusing capacity remained elevated (11%; P < 0.05) late in flight. These findings suggest that, despite increased pulmonary perfusion and pulmonary capillary blood volume, interstitial pulmonary edema does not result from exposure to microG.

  19. Pulmonary diffusing capacity for nitric oxide during exercise in morbid obesity.

    PubMed

    Zavorsky, Gerald S; Kim, Do J; McGregor, Elspeth R; Starling, Jennifer M; Gavard, Jeffrey A

    2008-11-01

    Morbidly obese individuals may have altered pulmonary diffusion during exercise. The purpose of this study was to examine pulmonary diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) during exercise in these subjects. Ten morbidly obese subjects (age = 38 +/- 9 years, BMI = 47 +/- 7 kg/m(2), peak oxygen consumption or VO(2peak) = 2.4 +/- 0.4 l/min) and nine nonobese controls (age = 41 +/- 9 years, BMI = 23 +/- 2 kg/m(2), VO(2peak) = 2.6 +/- 0.9 l/min) participated in two sessions: the first measured resting O(2) and VO(2peak) for determination of wattage equating to 40, 75, and 90% oxygen uptake reserve (VO(2)R). The second session measured pulmonary diffusion from single-breath maneuvers of 5 s each, as well as heart rate (HR) and VO(2) over three workloads. DLNO, DLCO, and pulmonary capillary blood volume were larger in obese compared to nonobese groups (P diffusion, whether or not expressed to VA, were not different between groups (P > 0.10). The morbidly obese have increased pulmonary diffusion per unit increase in VA compared with nonobese controls which may be due to a lower rise in VA per unit increase in VO(2) in the obese during exercise.

  20. Alveolar-Membrane Diffusing Capacity Limits Performance in Boston Marathon Qualifiers

    PubMed Central

    Lavin, Kaleen M.; Straub, Allison M.; Uhranowsky, Kathleen A.; Smoliga, James M.; Zavorsky, Gerald S.

    2012-01-01

    Purpose (1) to examine the relation between pulmonary diffusing capacity and marathon finishing time, and (2), to evaluate the accuracy of pulmonary diffusing capacity for nitric oxide (DLNO) in predicting marathon finishing time relative to that of pulmonary diffusing capacity for carbon monoxide (DLCO). Methods 28 runners [18 males, age = 37 (SD 9) years, body mass = 70 (13) kg, height = 173 (9) cm, percent body fat = 17 (7) %] completed a test battery consisting of measurement of DLNO and DLCO at rest, and a graded exercise test to determine running economy and aerobic capacity prior to the 2011 Steamtown Marathon (Scranton, PA). One to three weeks later, all runners completed the marathon (range: 2∶22:38 to 4∶48:55). Linear regressions determined the relation between finishing time and a variety of anthropometric characteristics, resting lung function variables, and exercise parameters. Results In runners meeting Boston Marathon qualification standards, 74% of the variance in marathon finishing time was accounted for by differences in DLNO relative to body surface area (BSA) (SEE = 11.8 min, p<0.01); however, the relation between DLNO or DLCO to finishing time was non-significant in the non-qualifiers (p = 0.14 to 0.46). Whereas both DLCO and DLNO were predictive of finishing time for all finishers, DLNO showed a stronger relation (r2 = 0.30, SEE = 33.4 min, p<0.01) compared to DLCO when considering BSA. Conclusion DLNO is a performance-limiting factor in only Boston qualifiers. This suggests that alveolar-capillary membrane conductance is a limitation to performance in faster marathoners. Additionally, DLNO/BSA predicts marathon finishing time and aerobic capacity more accurately than DLCO. PMID:22984520

  1. Does lung diffusion impairment affect exercise capacity in patients with heart failure?

    PubMed Central

    Agostoni, P G; Bussotti, M; Palermo, P; Guazzi, M

    2002-01-01

    Objective: To determine whether there is a relation between impairment of lung diffusion and reduced exercise capacity in chronic heart failure. Design: 40 patients with heart failure in stable clinical condition and 40 controls participated in the study. All subjects underwent standard pulmonary function tests plus measurements of resting lung diffusion (carbon monoxide transfer, Tlco), pulmonary capillary volume (Vc), and membrane resistance (Dm), and maximal cardiopulmonary exercise testing. In 20 patients and controls, the following investigations were also done: (1) resting and constant work rate Tlco; (2) maximal cardiopulmonary exercise testing with inspiratory O2 fractions of 0.21 and 0.16; and (3) rest and peak exercise blood gases. The other subjects underwent Tlco, Dm, and Vc measurements during constant work rate exercise. Results: In normoxia, exercise induced reductions of haemoglobin O2 saturation never occurred. With hypoxia, peak exercise uptake (peak V̇o2) decreased from (mean (SD)) 1285 (395) to 1081 (396) ml/min (p < 0.01) in patients, and from 1861 (563) to 1771 (457) ml/min (p < 0.05) in controls. Resting Tlco correlated with peak V̇o2 in heart failure (normoxia < hypoxia). In heart failure patients and normal subjects, Tlco and peak V̇o2 correlated with O2 arterial content at rest and during peak exercise in both normoxia and hypoxia. Tlco, Vc, and Dm increased during exercise. The increase in Tlco was greater in patients who had a smaller reduction of exercise capacity with hypoxia. Alveolar–arterial O2 gradient at peak correlated with exercise capacity in heart failure during normoxia and, to a greater extent, during hypoxia. Conclusions: Lung diffusion impairment is related to exercise capacity in heart failure. PMID:12381630

  2. Combined effects of inspired oxygen, carbon dioxide, and carbon monoxide on oxygen transport and aerobic capacity.

    PubMed

    Crocker, George H; Toth, Balazs; Jones, James H

    2013-09-01

    We hypothesized that breathing hypoxic, hypercapnic, and CO-containing gases together reduces maximal aerobic capacity (Vo2max) as the sum of each gas' individual effect on Vo2max. To test this hypothesis, goats breathed combinations of inspired O2 fraction (FiO2) of 0.06-0.21 and inspired CO2 fraction of 0.00 or 0.05, with and without inspired CO that elevated carboxyhemoglobin fraction (FHbCO) to 0.02-0.45, while running on a treadmill at speeds eliciting Vo2max. Individually, hypoxia and elevated FHbCO decreased fractional Vo2max (FVo2max, fraction of a goat's Vo2max breathing air) in linear, dose-dependent manners; hypercapnia did not change Vo2max. Concomitant hypoxia and elevated FHbCO decreased Vo2max less than the individual gas effects summed, indicating their combined effects on Vo2max are attenuated, fitting the following regression: FVo2max = 4.24 FiO2 + 0.519 FHbCO - 8.22 (FiO2 × FHbCO) + 0.117, (R(2) = 0.965, P < 0.001). The FVo2max correlated highly with total cardiopulmonary O2 delivery, not peripheral diffusing capacity, and with arterial O2 concentration (CaO2), not cardiac output. Hypoxia and elevated FHbCO decreased CaO2 by different mechanisms: hypoxia decreased arterial O2 saturation (SaO2), whereas elevated FHbCO decreased O2 capacitance {concentration of hemoglobin (Hb) available to bind O2 ([Hbavail])}. When breathing hypoxic gas (FiO2 0.12), CaO2 did not change with increasing FHbCO up to 0.30 because higher SaO2 of Hbavail offset decreased [Hbavail] due to the following: 1) hyperventilation with hypoxia and/or elevated FHbCO; 2) increased Hb affinity for O2 due to both Bohr and direct carboxyhemoglobin effects; and 3) the sigmoid relationship between O2 saturation and partial pressure elevating SaO2 more with hypoxia than normoxia.

  3. [Measurement of CO diffusion capacity (II): Standardization and quality criteria].

    PubMed

    Salcedo Posadas, A; Villa Asensi, J R; de Mir Messa, I; Sardón Prado, O; Larramona, H

    2015-08-01

    The diffusion capacity is the technique that measures the ability of the respiratory system for gas exchange, thus allowing a diagnosis of the malfunction of the alveolar-capillary unit. The most important parameter to assess is the CO diffusion capacity (DLCO). New methods are currently being used to measure the diffusion using nitric oxide (NO). There are other methods for measuring diffusion, although in this article the single breath technique is mainly referred to, as it is the most widely used and best standardized. Its complexity, its reference equations, differences in equipment, inter-patient variability and conditions in which the DLCO is performed, lead to a wide inter-laboratory variability, although its standardization makes this a more reliable and reproductive method. The practical aspects of the technique are analyzed, by specifying the recommendations to carry out a suitable procedure, the calibration routine, calculations and adjustments. Clinical applications are also discussed. An increase in the transfer of CO occurs in diseases in which there is an increased volume of blood in the pulmonary capillaries, such as in the polycythemia and pulmonary hemorrhage. There is a decrease in DLCO in patients with alveolar volume reduction or diffusion defects, either by altered alveolar-capillary membrane (interstitial diseases) or decreased volume of blood in the pulmonary capillaries (pulmonary embolism or primary pulmonary hypertension). Other causes of decreased or increased DLCO are also highlighted.

  4. [Measurement of CO diffusion capacity (II): Standardization and quality criteria].

    PubMed

    Salcedo Posadas, A; Villa Asensi, J R; de Mir Messa, I; Sardón Prado, O; Larramona, H

    2015-08-01

    The diffusion capacity is the technique that measures the ability of the respiratory system for gas exchange, thus allowing a diagnosis of the malfunction of the alveolar-capillary unit. The most important parameter to assess is the CO diffusion capacity (DLCO). New methods are currently being used to measure the diffusion using nitric oxide (NO). There are other methods for measuring diffusion, although in this article the single breath technique is mainly referred to, as it is the most widely used and best standardized. Its complexity, its reference equations, differences in equipment, inter-patient variability and conditions in which the DLCO is performed, lead to a wide inter-laboratory variability, although its standardization makes this a more reliable and reproductive method. The practical aspects of the technique are analyzed, by specifying the recommendations to carry out a suitable procedure, the calibration routine, calculations and adjustments. Clinical applications are also discussed. An increase in the transfer of CO occurs in diseases in which there is an increased volume of blood in the pulmonary capillaries, such as in the polycythemia and pulmonary hemorrhage. There is a decrease in DLCO in patients with alveolar volume reduction or diffusion defects, either by altered alveolar-capillary membrane (interstitial diseases) or decreased volume of blood in the pulmonary capillaries (pulmonary embolism or primary pulmonary hypertension). Other causes of decreased or increased DLCO are also highlighted. PMID:25488028

  5. The Single-Breath Diffusing Capacity of CO and NO in Healthy Children of European Descent

    PubMed Central

    Thomas, Astrid; Hanel, Birgitte; Marott, Jacob L.; Buchvald, Frederik; Mortensen, Jann; Nielsen, Kim G.

    2014-01-01

    Rationale The diffusing capacity (DL) of the lung can be divided into two components: the diffusing capacity of the alveolar membrane (Dm) and the pulmonary capillary volume (Vc). DL is traditionally measured using a single-breath method, involving inhalation of carbon monoxide, and a breath hold of 8–10 seconds (DL,CO). This method does not easily allow calculation of Dm and Vc. An alternative single-breath method (DL,CO,NO), involving simultaneous inhalation of carbon monoxide and nitric oxide, and traditionally a shorter breath hold, allows calculation of Dm and Vc and the DL,NO/DL,CO ratio in a single respiratory maneuver. The clinical utility of Dm, Vc, and DL,NO/DL,CO in the pediatric age range is currently unknown but also restricted by lack of reference values. Objectives The aim of this study was to establish reference ranges for the outcomes of DL,CO,NO with a 5 second breath hold, including the calculated outcomes Dm, Vc, and the DL,NO/DL,CO ratio, as well as to establish reference values for the outcomes of the traditional DL,CO method, with a 10 second breath hold in children. Methods DL,CO,NO and DL,CO were measured in healthy children, of European descent, aged 5–17 years using a Jaeger Masterscreen PFT. The data were analyzed using the Generalized Additive Models for Location Scale and Shape (GAMLSS) statistical method. Measurements and Main Results A total of 326 children were eligible for diffusing capacity measurements, resulting in 312 measurements of DL,CO,NO and 297 of DL,CO, respectively. Reference equations were established for the outcomes of DL,CO,NO and DL,CO, including the calculated values: Vc, Dm, and the DL,NO/DL,CO ratio. Conclusion These reference values are based on the largest sample of children to date and may provide a basis for future studies of their clinical utility in differentiating between alterations in the pulmonary circulation and changes in the alveolar membrane in pediatric patients. PMID:25514246

  6. Genetic Variation of SCNN1A Influences Lung Diffusing Capacity in Cystic Fibrosis

    PubMed Central

    Baker, Sarah E.; Wong, Eric C.; Wheatley, Courtney M.; Foxx-Lupo, William T.; Martinez, Marina G.; Morgan, Mary A.; Sprissler, Ryan; Morgan, Wayne J.; Snyder, Eric M.

    2012-01-01

    Introduction Epithelial Na+ Channels (ENaC) play a crucial role in ion and fluid regulation in the lung. In cystic fibrosis (CF) Na+ hyperabsorption results from ENaC over activity, leading to airway dehydration. Previous work has demonstrated functional genetic variation of SCNN1A (the gene encoding the ENaC α-subunit), manifesting as an alanine (A) to threonine (T) substitution at amino acid 663, with the αT663 variant resulting in a more active channel. Methods We assessed the influence of genetic variation of SCNN1A on the diffusing capacity of the lungs for carbon monoxide (DLCO) and nitric oxide (DLNO), together with alveolar capillary membrane conductance (DM), pulmonary capillary blood volume (VC), and alveolar volume (VA) at rest and during peak exercise in 18 patients with CF [10 homozygous for αA663 (AA group) and 8 with at least one T663 allele (AT/TT group)]. Due to the more active channel we hypothesized that the AT/TT group would show a greater increase in DLCO, DLNO, and DM with exercise due to exercise-mediated ENaC inhibition and subsequent attenuation of Na+ hyperabsorption. Results The AT/TT group had significantly lower pulmonary function, weight and BMI than the AA group. Both groups had similar peak workloads, relative peak oxygen consumptions, and cardiopulmonary responses to exercise. The AT/TT group demonstrated a greater increase in DLNO, DLNO/VA, and DM in response to exercise (% increases: DLNO= 18±11vs.41±38; DLNO/VA= 14±21vs.40±37; DM= 15±11vs.41±38, AAvs.AT/TT, respectively). There were no differences between groups in absolute diffusing capacity measures at peak exercise. Conclusion These results suggest that genetic variation of the alpha-subunit of ENaC differentially affects the diffusing capacity response to exercise in patients with CF. PMID:22776878

  7. Loss of alveolar membrane diffusing capacity and pulmonary capillary blood volume in pulmonary arterial hypertension

    PubMed Central

    2013-01-01

    Background Reduced gas transfer in patients with pulmonary arterial hypertension (PAH) is traditionally attributed to remodeling and progressive loss of pulmonary arterial vasculature that results in decreased capillary blood volume available for gas exchange. Methods We tested this hypothesis by determination of lung diffusing capacity (DL) and its components, the alveolar capillary membrane diffusing capacity (Dm) and lung capillary blood volume (Vc) in 28 individuals with PAH in comparison to 41 healthy individuals, and in 19 PAH patients over time. Using single breath simultaneous measure of diffusion of carbon monoxide (DLCO) and nitric oxide (DLNO), DL and Dm were respectively determined, and Vc calculated. Dm and Vc were evaluated over time in relation to standard clinical indicators of disease severity, including brain natriuretic peptide (BNP), 6-minute walk distance (6MWD) and right ventricular systolic pressure (RVSP) by echocardiography. Results Both DLCO and DLNO were reduced in PAH as compared to controls and the lower DL in PAH was due to loss of both Dm and Vc (all p < 0.01). While DLCO of PAH patients did not change over time, DLNO decreased by 24 ml/min/mmHg/year (p = 0.01). Consequently, Dm decreased and Vc tended to increase over time, which led to deterioration of the Dm/Vc ratio, a measure of alveolar-capillary membrane functional efficiency without changes in clinical markers. Conclusions The findings indicate that lower than normal gas transfer in PAH is due to loss of both Dm and Vc, but that deterioration of Dm/Vc over time is related to worsening membrane diffusion. PMID:23339456

  8. Risk of COPD with obstruction in active smokers with normal spirometry and reduced diffusion capacity.

    PubMed

    Harvey, Ben-Gary; Strulovici-Barel, Yael; Kaner, Robert J; Sanders, Abraham; Vincent, Thomas L; Mezey, Jason G; Crystal, Ronald G

    2015-12-01

    Smokers are assessed for chronic obstructive pulmonary disease (COPD) using spirometry, with COPD defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) as airflow limitation that is not fully reversible with bronchodilators. There is a subset of smokers with normal spirometry (by GOLD criteria), who have a low diffusing capacity of the lung for carbon monoxide (DLCO), a parameter linked to emphysema and small airway disease. The natural history of these "normal spirometry/low DLCO" smokers is unknown.From a cohort of 1570 smokers in the New York City metropolitian area, all of whom had normal spirometry, two groups were randomly selected for lung function follow-up: smokers with normal spirometry/normal DLCO (n=59) and smokers with normal spirometry/low DLCO (n=46). All had normal history, physical examination, complete blood count, urinalysis, HIV status, α1-antitrypsin level, chest radiography, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and total lung capacity. Throughout the study, all continued to be active smokers.In the normal spirometry/normal DLCO group assessed over 45±20 months, 3% developed GOLD-defined COPD. In contrast, in the normal spirometry/low DLCO group, followed over 41±31 months, 22% developed GOLD-defined COPD.Despite appearing "normal" according to GOLD, smokers with normal spirometry but low DLCO are at significant risk of developing COPD with obstruction to airflow.

  9. The effect of increased physical activity on pulmonary diffusing capacity in unfit women.

    PubMed

    Flaherty, Joseph M; Smoliga, James M; Zavorsky, Gerald S

    2014-03-01

    The purpose of the study was to determine whether short-term high-intensity aerobic interval training improves resting pulmonary diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO). Twenty-eight sedentary women [mean (SD) age 32 (11) years, body mass index 24.3 (5.7) kg m(-2)] were randomly assigned to either a self-directed moderate-intensity physical activity (n = 14) group or a supervised high-intensity aerobic interval training group (n = 14). The moderate physical activity group and the aerobic interval training group increased weekly physical activity energy expenditure by 800 and 1600 kcal week(-1), respectively. After 6 weeks, aerobic capacity increased to a similar exent in both groups (mean improvement 8%, effect size 0.39). The DLNO, but not DLCO, increased to a similar extent in both groups, by 4% or 3.0 (5.7) [95% confidence interval 0.8, 5.2] ml min(-1) mmHg(-1) m(-2) from pre- to post-training (effect size 0.27). There was no correlation between the change in aerobic capacity and the change in DLNO (P > 0.05) or between the change in aerobic capacity and the change in total weekly physical activity energy expenditure (P > 0.05). Interval training does not provide additional improvements in DLNO or aerobic capacity compared with self-directed moderate-intensity physical activity (4-6 metabolic equivalent tasks, 800 kcal week(-1), for 6 weeks) in unfit women. Despite the slight improvement in both DLNO and aerobic capacity, true meaningful physiological changes in these parameters remain questionable.

  10. Lung diffusing capacity for nitric oxide as a marker of fibrotic changes in idiopathic interstitial pneumonias.

    PubMed

    Barisione, Giovanni; Brusasco, Claudia; Garlaschi, Alessandro; Baroffio, Michele; Brusasco, Vito

    2016-05-01

    Lung diffusing capacity for carbon monoxide (DLCO) is decreased in both usual interstitial pneumonia-idiopathic pulmonary fibrosis (UIP-IPF) and nonspecific interstitial pneumonia (NSIP), but is moderately related to computed tomography (CT)-determined fibrotic changes. This may be due to the relative insensitivity of DLCO to changes in alveolar membrane diffusive conductance (DMCO). The purpose of this study was to determine whether measurement of lung diffusing capacity for nitric oxide (DLNO) better reflects fibrotic changes than DLCO DLNO-DLCO were measured simultaneously in 30 patients with UIP-IPF and 30 with NSIP. Eighty-one matched healthy subjects served as a control group. The amount of pulmonary fibrosis was estimated by CT volumetric analysis of visually bounded areas showing reticular opacities and honeycombing. DMCO and pulmonary capillary volume (VC) were calculated. DLNO was below the lower limit of normal in all patients irrespective of extent and nature of disease, whereas DLCO was within the normal range in a nonnegligible number of patients. Both DLNO and DLCO were significantly correlated with visual assessment of fibrosis but DLNO more closely than DLCO DMCO was also below the lower limit of normal in all UIP-IPF and NSIP patients and significantly correlated with fibrosis extent in both diseases, whereas VC was weakly correlated with fibrosis in UIP-IPF and uncorrelated in NSIP, with normal values in half of patients. In conclusion, measurement of DLNO may provide a more sensitive evaluation of fibrotic changes than DLCO in either UIP-IPF or NSIP, because it better reflects DMCO.

  11. Abnormal Gas Diffusing Capacity and Portosystemic Shunt in Patients With Chronic Liver Disease

    PubMed Central

    Park, Moon-Seung; Lee, Min-Ho; Park, Yoo-Sin; Kim, Shin-Hee; Kwak, Min-Jung; Kang, Ju-Seop

    2012-01-01

    Background Pulmonary dysfunctions including the hepatopulmonary syndrome and portosystemic shunt are important complications of hepatic cirrhosis. To investigate the severity and nature of abnormal gas diffusing capacity and its correlation to portosystemic shunt in patients with chronic liver disease. Methods Forty-four patients with chronic liver disease (15 chronic active hepatitis (CAH), 16 Child-Pugh class A, and 13 Child-Pugh class B) without other diseases history were enrolled in the study. Evaluation of liver function tests, arterial blood gases analysis, ultrasonography, pulmonary function test including lung diffusing capacity of carbon monoxide (DLco), forced vital capacity(FVC), forced expiratory volume 1 seconds(FEV1), total lung capacity(TLC), DLco/AV(alveolar volume) and thallium-201 per rectum scintigraphy were performed. We were analyzed correlations between pulmonary function abnormalities and heart/liver (H/L) ratio in patients with chronic liver diseases. Results In CAH, percentage of patients with DLco and DLco/VA (< 80%) was 22.2 % but it was significantly increased to 47.2-54.5% in Child-Pugh class A and B patients. The means of DLco and DLco/VA were significantly (P < 0.05) decreased in Child-Pugh class. The mean H/L ratio in Child-Pugh class B increased markedly (P < 0.01) than those with CAH and Child-Pugh class A. The frequency of specific pulmonary function abnormality in patients with Child-Pugh class B was significantly (P < 0.01) greater than those with Child-Pugh class A and CAH. There was a inverse linear correlation between H/L ratio and DLco (r = -0.339, P < 0.05) and DLco/VA (r = -0.480, P < 0.01). Conclusion A total of 62% of patients with advanced liver disease have abnormal pulmonary diffusion capacity with a reduced DLco or DLco/VA and abnormal portosystemic shunt (increased H/L ratio) is common hemodynamic abnormality. Therefore, inverse linear correlation between DLco or DLco/VA and H/L ratio may be an important factor in

  12. Associations of autophagy with lung diffusion capacity and oxygen saturation in severe COPD: effects of particulate air pollution

    PubMed Central

    Lee, Kang-Yun; Chiang, Ling-Ling; Ho, Shu-Chuan; Liu, Wen-Te; Chen, Tzu-Tao; Feng, Po-Hao; Su, Chien-Ling; Chuang, Kai-Jen; Chang, Chih-Cheng; Chuang, Hsiao-Chi

    2016-01-01

    Although traffic exposure has been associated with the development of COPD, the role of particulate matter <10 μm in aerodynamic diameter (PM10) in the pathogenesis of COPD is not yet fully understood. We assessed the 1-year effect of exposure to PM10 on the pathogenesis of COPD in a retrospective cohort study. We recruited 53 subjects with COPD stages III and IV and 15 healthy controls in a hospital in Taiwan. We estimated the 1-year annual mean levels of PM10 at all residential addresses of the cohort participants. Changes in PM10 for the 1-year averages in quintiles were related to diffusion capacity of the lung for carbon monoxide levels (r=−0.914, P=0.029), changes in the pulse oxygen saturation (ΔSaO2; r=−0.973, P=0.005), receptor for advanced glycation end-products (r=−0.881, P=0.048), interleukin-6 (r=0.986, P=0.002), ubiquitin (r=0.940, P=0.017), and beclin 1 (r=0.923, P=0.025) in COPD. Next, we observed that ubiquitin was correlated with ΔSaO2 (r=−0.374, P=0.019). Beclin 1 was associated with diffusion capacity of the lung for carbon monoxide (r=−0.362, P=0.028), ΔSaO2 (r=−0.354, P=0.032), and receptor for advanced glycation end-products (r=−0.471, P=0.004). Autophagy may be an important regulator of the PM10-related pathogenesis of COPD, which could cause deterioration in the lung diffusion capacity and oxygen saturation. PMID:27468231

  13. Assessing recruitment of lung diffusing capacity in exercising guinea pigs with a rebreathing technique

    PubMed Central

    Yilmaz, Cuneyt; Dane, D. Merrill; Hsia, Connie C. W.

    2008-01-01

    Noninvasive techniques for assessing cardiopulmonary function in small animals are limited. We previously developed a rebreathing technique for measuring lung volume, pulmonary blood flow, diffusing capacity for carbon monoxide (DlCO) and its components, membrane diffusing capacity (DmCO) and pulmonary capillary blood volume (Vc), and septal volume, in conscious nonsedated guinea pigs at rest. Now we have extended this technique to study guinea pigs during voluntary treadmill exercise with a sealed respiratory mask attached to a body vest and a test gas mixture containing 0.5% SF6 or Ne, 0.3% CO, and 0.8% C2H2 in 40% or 98% O2. From rest to exercise, O2 uptake increased from 12.7 to 25.5 ml·min−1·kg−1 while pulmonary blood flow increased from 123 to 239 ml/kg. The measured DlCO, DmCO, and Vc increased linearly with respect to pulmonary blood flow as expected from alveolar microvascular recruitment; body mass-specific relationships were consistent with those in healthy human subjects and dogs studied with a similar technique. The results show that 1) cardiopulmonary interactions from rest to exercise can be measured noninvasively in guinea pigs, 2) guinea pigs exhibit patterns of exercise response and alveolar microvascular recruitment similar to those of larger species, and 3) the rebreathing technique is widely applicable to human (∼70 kg), dog (20–30 kg), and guinea pig (1–1.5 kg). In theory, this technique can be extended to even smaller animals provided that species-specific technical hurdles can be overcome. PMID:18483171

  14. Vertical Distributions of Pulmonary Diffusing Capacity and Capillary Blood Flow in Man

    PubMed Central

    Michaelson, Edward D.; Sackner, Marvin A.; Johnson, Robert L.

    1973-01-01

    In six normal upright subjects, a 100 mol bolus—composed of equal parts of neon, carbon monoxide, and acetylene (Ne, CO, and C2H2)—was inspired from either residual volume (RV) or functional residual capacity (FRC) during a slow inspiration from RV to total lung capacity (TLC). After breath holding and subsequent collection of the exhalate, diffusing capacity and pulmonary capillary blood flow per liter of lung volume (DL/VA and Q̇C/VA) were calculated from the rates of CO and C2H2 disappearances relative to Ne. The means: DL/VA = 5.26 ml/min × mm Hg per liter (bolus at RV), 6.54 ml/min × mm Hg per liter (at FRC); Q̇C/VA 0.537 liters/minute per liter (bolus at RV), 0.992 liters/minute per liter (at FRC). Similar maneuvers using Xenon-133 confirmed that, during inspiration, more of the bolus goes to the upper zone if introduced at RV and more to the lower, if at FRC. A lung model has been constructed which describes how DL/VA and Q̇C/VA must be distributed to satisfy the experimental data. According to this model, there is a steep gradient of Q̇C/VA, increasing from apex to base, similar to that previously determined by other techniques—and also a gradient in the same direction, although not as steep, for DL/VA. This more uniform distribution of DL/VA compared with Q̇C/VA indicates a vertical unevenness of diffusing capacity with respect to blood flow (DL/Q̇C). However, the relative degree of vertical unevenness of DL/VA compared with Q̇C/VA can account only in part for previous observations attributed to the inhomogeneity of DL/VA and Q̇C/VA. Thus, a more generalized unevennes of these ratios must exist throughout the lung, independent of gravitation. Images PMID:4683876

  15. CO and NO pulmonary diffusing capacity during pregnancy: Safety and diagnostic potential

    PubMed Central

    Zavorsky, Gerald S.; Blood, Arlin B.; Power, Gordon G.; Longo, Lawrence D.; Artal, Raul; Vlastos, Emanuel J.

    2013-01-01

    This paper reviews the scientific evidence for the safety of carbon monoxide (CO) and nitric oxide (NO) inhalation to measure pulmonary diffusing capacity (DLCO and DLNO) in pregnant women and their fetuses. In eight earlier studies, 650 pregnant women had DLCO measurements performed at various times during pregnancy, with a minimum of two to four tests per session. Both pregnant subjects that were healthy and those with medical complications were tested. No study reported adverse maternal, fetal, or neonatal outcomes from the CO inhalation in association with measuring DLCO. Eleven pregnant women, chiefly with pulmonary hypertension, and 1105 pre-term neonates, mostly with respiratory failure, were administered various dosages of NO (5–80 ppm for 4 weeks continuously in pregnant women, and 1–20 ppm for 15 min to 3 weeks for the neonates). NO treatment was found to be an effective therapy for pregnant women with pulmonary hypertension. In neonates with respiratory failure and pulmonary hypertension, NO therapy improved oxygenation and survival and has been associated with only minor, transient adverse effects. In conclusion, maternal carboxyhemoglobin ([HbCO]) levels can safely increase to 5% per testing session when the dose-exposure limit is 0.3% CO inhalation for ≤3 min, and for NO, 80 ppm for ≤ 3 min. The risk of late fetal or neonatal death from increased HbCO from diffusion testing is considerably less than the risk of death from all causes reported by the Centers for Disease Control, and is therefore considered “minimal risk”. PMID:20149901

  16. Prediction equations for diffusing capacity (transfer factor) of lung for North Indians

    PubMed Central

    Chhabra, Sunil Kumar; Kumar, Rajeev; Gupta, Uday A

    2016-01-01

    Background: Prediction equations for diffusing capacity of lung for carbon monoxide (DLCO), alveolar volume (VA), and DLCO/VA using the current standardization guidelines are not available for Indian population. The present study was carried out to develop equations for these parameters for North Indian adults and examine the ethnic diversity in predictions. Materials and Methods: DLCO was measured by single-breath technique and VA by single-breath helium dilution using standardized methodology in 357 (258 males, 99 females) normal nonsmoker adult North Indians and DLCO/VA was computed. The subjects were randomized into training and test datasets for development of prediction equations by multiple linear regressions and for validation, respectively. Results: For males, the following equations were developed: DLCO, −7.813 + 0.318 × ht −0.624 × age + 0.00552 × age2; VA, −8.152 + 0.087 × ht −0.019 × wt; DLCO/VA, 7.315 − 0.037 × age. For females, the equations were: DLCO, −44.15 + 0.449 × ht −0.099 × age; VA, −6.893 + 0.068 × ht. A statistically acceptable prediction equation was not obtained for DLCO/VA in females. It was therefore computed from predicted DLCO and predicted VA. All equations were internally valid. Predictions of DLCO by Indian equations were lower than most Caucasian predictions in both males and females and greater than the Chinese predictions for males. Conclusion: This study has developed validated prediction equations for DLCO, VA, and DLCO/VA in North Indians. Substantial ethnic diversity exists in predictions for DLCO and VA with Caucasian equations generally yielding higher values than the Indian or Chinese equations. However, DLCO/VA predicted by the Indian equations is slightly higher than that by other equations. PMID:27625439

  17. Prediction equations for diffusing capacity (transfer factor) of lung for North Indians

    PubMed Central

    Chhabra, Sunil Kumar; Kumar, Rajeev; Gupta, Uday A

    2016-01-01

    Background: Prediction equations for diffusing capacity of lung for carbon monoxide (DLCO), alveolar volume (VA), and DLCO/VA using the current standardization guidelines are not available for Indian population. The present study was carried out to develop equations for these parameters for North Indian adults and examine the ethnic diversity in predictions. Materials and Methods: DLCO was measured by single-breath technique and VA by single-breath helium dilution using standardized methodology in 357 (258 males, 99 females) normal nonsmoker adult North Indians and DLCO/VA was computed. The subjects were randomized into training and test datasets for development of prediction equations by multiple linear regressions and for validation, respectively. Results: For males, the following equations were developed: DLCO, −7.813 + 0.318 × ht −0.624 × age + 0.00552 × age2; VA, −8.152 + 0.087 × ht −0.019 × wt; DLCO/VA, 7.315 − 0.037 × age. For females, the equations were: DLCO, −44.15 + 0.449 × ht −0.099 × age; VA, −6.893 + 0.068 × ht. A statistically acceptable prediction equation was not obtained for DLCO/VA in females. It was therefore computed from predicted DLCO and predicted VA. All equations were internally valid. Predictions of DLCO by Indian equations were lower than most Caucasian predictions in both males and females and greater than the Chinese predictions for males. Conclusion: This study has developed validated prediction equations for DLCO, VA, and DLCO/VA in North Indians. Substantial ethnic diversity exists in predictions for DLCO and VA with Caucasian equations generally yielding higher values than the Indian or Chinese equations. However, DLCO/VA predicted by the Indian equations is slightly higher than that by other equations.

  18. Change in pulmonary diffusion capacity in a general population sample over 9 years

    PubMed Central

    Storebø, Michael L.; Eagan, Tomas M. L.; Eide, Geir E.; Gulsvik, Amund; Thorsen, Einar; Bakke, Per S.

    2016-01-01

    Rationale Data on the change in diffusion capacity of the lung for carbon monoxide (DLCO) over time are limited. We aimed to examine change in DLCO (ΔDLCO) over a 9-year period and its predictors. Methods A Norwegian community sample comprising 1,152 subjects aged 18–73 years was examined in 1987 and 1988. Of the 1,109 subjects still alive, 830 (75%) were re-examined in 1996/97. DLCO was measured with the single breath-holding technique. Covariables recorded at baseline included sex, age, height, weight, smoking status, pack years, occupational exposure, educational level, and spirometry. Generalized estimating equations analyses were performed to examine relations between ΔDLCO and the covariables. Results At baseline, mean [standard deviation (SD)] DLCO was 10.8 (2.4) and 7.8 (1.6) mmol·min−1·kPa−1 in men and women, respectively. Mean (SD) ΔDLCO was −0.24 (1.31) mmol·min−1·kPa−1. ΔDLCO was negatively related to baseline age, DLCO, current smoking, and pack years, and positively related to forced expiratory volume in 1 second (FEV1) and weight. Sex, occupational exposure, and educational level were not related to ΔDLCO. Conclusions In a community sample, more rapid decline in DLCO during 9 years of observation time was related to higher age, baseline current smoking, more pack years, larger weight, and lower FEV1. PMID:27600696

  19. Carbon monoxide intoxication

    SciTech Connect

    Kales, S.N. )

    1993-11-01

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

  20. Lower diffusing capacity with chronic bronchitis predicts higher risk of acute exacerbation in chronic obstructive lung disease

    PubMed Central

    Lee, Hwa Young; Kim, Jin Woo; Lee, Sang Haak; Yoon, Hyoung Kyu; Shim, Jae Jeong; Park, Jeong-Woong; Lee, Jae-Hyung; Yoo, Kwang Ha; Jung, Ki-Suck

    2016-01-01

    Background This study was designed to evaluate the effect of chronic bronchitis (CB) symptoms and degree of emphysema in a multicenter Korean cohort. Methods From April 2012 to May 2015, patients diagnosed with chronic obstructive lung disease (COPD) who were aged above 40 years at 46 hospitals throughout Korea were enrolled. All of the patients were classified according to CB symptoms and the diffusing capacity of the lung for carbon monoxide (DLCO); demographic data, symptom scores, and the result of lung function tests and exacerbations were then analyzed. Results A total of 812 patients were enrolled. Among these patients, 285 (35.1%) had CB symptoms. A total of 51% of patients had high DLCO without CB symptoms [CB (−) high DLCO], 24.9% had CB symptoms only [CB (+) high DLCO], 14.2% had low DLCO only [CB (−) low DLCO], and 10.2% had both low DLCO and CB [CB (+) low DLCO]. Patients with CB (+) low DLCO showed a significantly lower post-bronchodilator (BD) forced expiratory volume for 1 second (FEV1) and more severe dyspnea than patients with CB (−) high DLCO. On multivariate analysis, the risk of acute exacerbation was two times higher [odds ratio (OR) 2.06; 95% confidence interval (CI): 1.18–3.62; P=0.01] in the CB (+) low DLCO group than in the CB (−) high DLCO group. Conclusions In this COPD cohort, patients showed distinct clinical characteristics and outcomes according to the presence of CB and degree of DLCO. CB and low DLCO were associated with the risk of acute exacerbation. PMID:27293847

  1. Pulmonary diffusing capacity, capillary blood volume, and cardiac output during sustained microgravity

    NASA Technical Reports Server (NTRS)

    Prisk, G. K.; Guy, Harold J. B.; Elliott, Ann R.; Deutschman, Robert A., III; West, John B.

    1993-01-01

    We measured pulmonary diffusing capacity (DL), diffusing capacity per unit lung volume, pulmonary capillary blood volume (Vc), membrane diffusing capacity (Dm), pulmonary capillary blood flow or cardiac output (Qc), and cardiac stroke volume (SV) in four subjects exposed to nine days of microgravity. DL in microgravity was elevated compared with preflight standing values and was higher than preflight supine because of the elevation of both Vc and Dm. The elevation in Vc was comparable to that measured supine in 1 G, but the increase in Dm was in sharp contrast to the supine value. We postulate that, in 0 G, pulmonary capillary blood is evenly distributed throughout the lung, providing for uniform capillary filling, leading to an increase in the surface area available for diffusion. By contrast, in the supine 1-G state, the capillaries are less evenly filled, and although a similar increase in blood volume is observed, the corresponding increase in surface area does not occur. DL and its subdivisions showed no adaptive changes from the first measurement 24 h after the start of 0 G to eight days later. Similarly, there were no trends in the postflight data, suggesting that the principal mechanism of these changes was gravitational. The increase in Dm suggests that subclinical pulmonary edema did not result from exposure to 0 G. Qc was modestly increased inflight and decreased postflight compared with preflight standing. Compared with preflight standing, SV was increased 46 percent inflight and decreased 14 percent in the 1st week postflight. There were temporal changes in Qc and SV during 0 G, with the highest values recorded at the first measurement, 24 h into the flight. The lowest values of Qc and SV occurred on the day of return.

  2. Breakdown of lung framework and an increase in pores of Kohn as initial events of emphysema and a cause of reduction in diffusing capacity

    PubMed Central

    Yoshikawa, Akira; Sato, Shuntaro; Tanaka, Tomonori; Hashisako, Mikiko; Kashima, Yukio; Tsuchiya, Tomoshi; Yamasaki, Naoya; Nagayasu, Takeshi; Yamamoto, Hiroshi; Fukuoka, Junya

    2016-01-01

    Purpose Pulmonary emphysema is the pathological prototype of chronic obstructive pulmonary disease and is also associated with other lung diseases. We considered that observation with different approaches may provide new insights for the pathogenesis of emphysema. Patients and methods We reviewed tissue blocks of the lungs of 25 cases with/without emphysema and applied a three-dimensional observation method to the blocks. Based on the three-dimensional characteristics of the alveolar structure, we considered one face of the alveolar polyhedron as a structural unit of alveoli and called it a framework unit (FU). We categorized FUs based on their morphological characteristics and counted their number to evaluate the destructive changes in alveoli. We also evaluated the number and the area of pores of Kohn in FUs. We performed linear regression analysis to estimate the effect of these data on pulmonary function tests. Results In multivariable regression analysis, a decrease in the number of FUs without an alveolar wall led to a significant decrease in the diffusing capacity of the lung for carbon monoxide (DLCO) and DLCO per unit alveolar volume, and an increase in the area of pores of Kohn had a significant effect on an increase in residual capacity. Conclusion A breakdown in the lung framework and an increase in pores of Kohn are associated with a decrease in DLCO and DLCO per unit alveolar volume with/without emphysema. PMID:27695315

  3. Breakdown of lung framework and an increase in pores of Kohn as initial events of emphysema and a cause of reduction in diffusing capacity

    PubMed Central

    Yoshikawa, Akira; Sato, Shuntaro; Tanaka, Tomonori; Hashisako, Mikiko; Kashima, Yukio; Tsuchiya, Tomoshi; Yamasaki, Naoya; Nagayasu, Takeshi; Yamamoto, Hiroshi; Fukuoka, Junya

    2016-01-01

    Purpose Pulmonary emphysema is the pathological prototype of chronic obstructive pulmonary disease and is also associated with other lung diseases. We considered that observation with different approaches may provide new insights for the pathogenesis of emphysema. Patients and methods We reviewed tissue blocks of the lungs of 25 cases with/without emphysema and applied a three-dimensional observation method to the blocks. Based on the three-dimensional characteristics of the alveolar structure, we considered one face of the alveolar polyhedron as a structural unit of alveoli and called it a framework unit (FU). We categorized FUs based on their morphological characteristics and counted their number to evaluate the destructive changes in alveoli. We also evaluated the number and the area of pores of Kohn in FUs. We performed linear regression analysis to estimate the effect of these data on pulmonary function tests. Results In multivariable regression analysis, a decrease in the number of FUs without an alveolar wall led to a significant decrease in the diffusing capacity of the lung for carbon monoxide (DLCO) and DLCO per unit alveolar volume, and an increase in the area of pores of Kohn had a significant effect on an increase in residual capacity. Conclusion A breakdown in the lung framework and an increase in pores of Kohn are associated with a decrease in DLCO and DLCO per unit alveolar volume with/without emphysema.

  4. Diffusing capacity and spirometry following a 60-minute dive to 4.5 meters.

    PubMed

    Koehle, M S; Hodges, A N H; Lynn, B M; Rachich, M F; McKenzie, D C

    2006-01-01

    The purpose of this study was to assess the contribution of SCUBA to the pulmonary effects of diving to 4.5 meters depth in healthy subjects using a randomized crossover control condition. Ten healthy divers performed two 60-minute 'dives' using SCUBA in a swimming pool. The non-immersed 1 ATA SCUBA control exposure took place at ambient pressure in the laboratory. Thirty minutes prior to, and 30 and 90 minutes post-exposure, FVC (forced vital capacity), FEV1.0 (forced expired volume), peak expiratory flow rate (PEFR), diffusing capacity (DL(co)), heart rate (HR) and temperature were measured. No significant differences were noted in HR, temperature or spirometry between the two conditions. A significant reduction in diffusing capacity occurred at 30 and 90 minutes after the pool dive (9.3% and 15.1%, respectively, p < 0.05). There was no concordant change in DL(co) following the non-immersed 1 ATA SCUBA control. Thus, a pool dive to 4.5 meters for 60 minutes causes a decrease in DL(co), without a change in spirometry, while breathing from SCUBA equipment without immersion causes no significant change in lung function.

  5. Single-breath diffusing capacity of NO independent of inspiratory NO concentration in rabbits.

    PubMed

    Heller, H; Schuster, K D

    1997-12-01

    Pulmonary diffusing capacity of NO (DLNO) was determined by performing single-breath experiments on six anesthetized paralyzed supine rabbits, applying inspiratory concentrations of NO (FINO) within a range of 10 parts per million (ppm) < or = FINO < or = 800 ppm. Starting from residual volume, the rabbit lungs were inflated by 50 ml of a NO-nitrogen-containing indicator gas mixture. Breath-holding time was set at 0.1, 1, 3, 5, and 7 s. Alveolar partial pressure of NO was determined by analyzing the end-tidal portion from expirates, with the use of respiratory mass spectrometry. In the six animals, pulmonary diffusing capacity of NO averaged DLNO = 1.92 +/- 0.21 ml.mmHg-1.min-1 (mean +/- SD value). Despite extreme variations in FINO, we found very similar DLNO values, and in three rabbits we found identical values even at such different FINO levels of 80 ppm or 500, 20, or 200 ppm as well as 10 or 800 ppm. There was also no dependence of DLNO on the respective duration of the single-breath maneuvers. In addition, the time course of NO removal from alveolar space was independent of applied FINO levels. These results suggest that DLNO determinations are neither affected by chemical reactions of NO in alveolar gas phase as well as in lung tissue nor biased by endogenous release of NO from pulmonary tissue. It is our conclusion that the single-breath diffusing capacity of NO is able to provide a measure of alveolar-capillary gas conductance that is not influenced by the biochemical reactions of NO.

  6. Severe dyspnoea with alteration of the diffusion capacity of the lung associated with fingolimod treatment.

    PubMed

    Bianco, Assunta; Patanella, Agata Katia; Nociti, Viviana; De Fino, Chiara; Lucchini, Matteo; Savio, Francesco Lo; Rossini, Paolo Maria; Mirabella, Massimiliano

    2016-09-01

    In phase II clinical trial, fingolimod at a dose of 5.0mg (ten times higher than the currently approved dose) induced dyspnoea and decreased forced expiratory flow in some patients, probably trought an airways constriction S1P4-mediated. In phase III trials, respiratory adverse events associated with fingolimod treatment as dyspnoea, cough, oropharingeal pain and nasal congestion are reported with the same incidence of placebo. Here we report two cases of severe dyspnoea with alteration of the diffusion capacity of the lung associated with fingolimod treatment, which led to permanent treatment withdrawal. PMID:27645336

  7. Gas exchange: large surface and thin barrier determine pulmonary diffusing capacity.

    PubMed

    Weibel, E R

    1999-06-01

    The lung is characterized by its diffusing capacity for oxygen, DLO2, which is estimated from morphometric information as a theoretical capacity. It is determined by the large gas exchange surface, the thin tissue barrier, and the amount of capillary blood. The question is asked whether DLO2 could be a limiting factor for O2 uptake in heavy exercise, particularly in athletes with their 50% higher O2 demand. This is answered by studying the relation between DLO2 and maximal O2 consumption in different sedentary and athletic mammals, comparing horse and cow, dog and goat, and, finally, the most athletic mammal, the pronghorn antelope of the Rocky Mountains. It is concluded that in athletic species the lung is just sufficient to satisfy the O2 needs and can therefore be a limiting factor for aerobic work. PMID:10394805

  8. Modeling carbon monoxide uptake during work

    SciTech Connect

    Bernard, T.E.; Duker, J.

    1981-05-01

    Acute carbon monoxide poisoning is the result of a diminished capacity of the blood to transport oxygen and sustain a level of metabolic activity. The diminished capacity is expressed in terms of the carboxyhemoglobin (COHb) level in the blood which is dependent upon the concentration of CO in the inhaled air. The rate of CO uptake or elimination is dependent upon the concentration of CO in the air as well as pulmonary diffusion capacity and alveolar ventilation which change with different metabolic rates. Coburn, Forster, and Kane (CFK) developed a mathematical model to describe the uptake and elimination kinetics of CO in sedentary individuals. The CFK model was used in a mathematical simulation of CO uptake and elimination where the independent variables were inhaled CO concentration and metabolic rate. The metabolic rate was used to specify pulmonary diffusing capacity and alveolar ventilation. As the level of COHb increased the metabolic rate was decreased to a level compatible with the impaired oxygen transport. A physical fatigue limit was also included. The theoretical model was used to simulate conditions beyond the range of exposures permissible under experimental laboratory conditions.

  9. Morphological respiratory diffusion capacity of the lungs of ball pythons (Python regius).

    PubMed

    Starck, J Matthias; Aupperle, Heike; Kiefer, Ingmar; Weimer, Isabel; Krautwald-Junghanns, Maria-Elisabeth; Pees, Michael

    2012-08-01

    This study aims at a functional and morphological characterization of the lung of a boid snake. In particular, we were interested to see if the python's lungs are designed with excess capacity as compared to resting and working oxygen demands. Therefore, the morphological respiratory diffusion capacity of ball pythons (Python regius) was examined following a stereological, hierarchically nested approach. The volume of the respiratory exchange tissue was determined using computed tomography. Tissue compartments were quantified using stereological methods on light microscopic images. The tissue diffusion barrier for oxygen transport was characterized and measured using transmission electron micrographs. We found a significant negative correlation between body mass and the volume of respiratory tissue; the lungs of larger snakes had relatively less respiratory tissue. Therefore, mass-specific respiratory tissue was calculated to exclude effects of body mass. The volume of the lung that contains parenchyma was 11.9±5.0mm(3)g(-1). The volume fraction, i.e., the actual pulmonary exchange tissue per lung parenchyma, was 63.22±7.3%; the total respiratory surface was, on average, 0.214±0.129m(2); it was significantly negatively correlated to body mass, with larger snakes having proportionally smaller respiratory surfaces. For the air-blood barrier, a harmonic mean of 0.78±0.05μm was found, with the epithelial layer representing the thickest part of the barrier. Based on these findings, a median diffusion capacity of the tissue barrier ( [Formula: see text] ) of 0.69±0.38ml O(2)min(-1)mmHg(-1) was calculated. Based on published values for blood oxygen concentration, a total oxygen uptake capacity of 61.16mlO(2)min(-1)kg(-1) can be assumed. This value exceeds the maximum demand for oxygen in ball pythons by a factor of 12. We conclude that healthy individuals of P. regius possess a considerable spare capacity for tissue oxygen exchange. PMID:22770588

  10. Morphological respiratory diffusion capacity of the lungs of ball pythons (Python regius).

    PubMed

    Starck, J Matthias; Aupperle, Heike; Kiefer, Ingmar; Weimer, Isabel; Krautwald-Junghanns, Maria-Elisabeth; Pees, Michael

    2012-08-01

    This study aims at a functional and morphological characterization of the lung of a boid snake. In particular, we were interested to see if the python's lungs are designed with excess capacity as compared to resting and working oxygen demands. Therefore, the morphological respiratory diffusion capacity of ball pythons (Python regius) was examined following a stereological, hierarchically nested approach. The volume of the respiratory exchange tissue was determined using computed tomography. Tissue compartments were quantified using stereological methods on light microscopic images. The tissue diffusion barrier for oxygen transport was characterized and measured using transmission electron micrographs. We found a significant negative correlation between body mass and the volume of respiratory tissue; the lungs of larger snakes had relatively less respiratory tissue. Therefore, mass-specific respiratory tissue was calculated to exclude effects of body mass. The volume of the lung that contains parenchyma was 11.9±5.0mm(3)g(-1). The volume fraction, i.e., the actual pulmonary exchange tissue per lung parenchyma, was 63.22±7.3%; the total respiratory surface was, on average, 0.214±0.129m(2); it was significantly negatively correlated to body mass, with larger snakes having proportionally smaller respiratory surfaces. For the air-blood barrier, a harmonic mean of 0.78±0.05μm was found, with the epithelial layer representing the thickest part of the barrier. Based on these findings, a median diffusion capacity of the tissue barrier ( [Formula: see text] ) of 0.69±0.38ml O(2)min(-1)mmHg(-1) was calculated. Based on published values for blood oxygen concentration, a total oxygen uptake capacity of 61.16mlO(2)min(-1)kg(-1) can be assumed. This value exceeds the maximum demand for oxygen in ball pythons by a factor of 12. We conclude that healthy individuals of P. regius possess a considerable spare capacity for tissue oxygen exchange.

  11. Calibration of High Temperature Thermal Conductivity System: New Algorithm to Measure Heat Capacity Using Flash Thermal Diffusivity in Thermoelectric Materials

    NASA Technical Reports Server (NTRS)

    Deb, Rahul; Snyder, Jeff G.

    2005-01-01

    A viewgraph presentation describing thermoelectric materials, an algorithm for heat capacity measurements and the process of flash thermal diffusivity. The contents include: 1) What are Thermoelectrics?; 2) Thermoelectric Applications; 3) Improving Thermoelectrics; 4) Research Goal; 5) Flash Thermal Diffusivity; 6) Background Effects; 7) Stainless Steel Comparison; 8) Pulse Max Integral; and 9) Graphite Comparison Algorithm.

  12. Carbon Monoxide Information Center

    MedlinePlus

    ... Monoxide Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible Killer" because it's a colorless, odorless, poisonous gas. ...

  13. Mechanisms for reduced pulmonary diffusing capacity in haematopoietic stem-cell transplantation recipients.

    PubMed

    Barisione, Giovanni; Bacigalupo, Andrea; Brusasco, Claudia; Scanarotti, Chiara; Penco, Susanna; Bassi, Anna Maria; Lamparelli, Teresa; Garlaschi, Alessandro; Pellegrino, Riccardo; Brusasco, Vito

    2014-04-01

    Lung diffusing capacity for CO (DLCO) is compromised in haematopoietic stem-cell transplantation (HSCT) recipients. We derived alveolar-capillary membrane conductance (DM,CO) and pulmonary capillary volume (VC) from DLCO and diffusing capacity for NO (DLNO). Forty patients were studied before and 6 weeks after HSCT. Before HSCT, DLNO and DLCO were significantly lower than in 30 healthy controls. DM,CO was ∼40% lower in patients than in controls (p<0.001), whereas VC did not differ significantly. After HSCT, DLNO and DM,CO further decreased, the latter by ∼22% from before HSCT (p<0.01) while VC did not change significantly. Lung density, serum CRP and reactive oxygen metabolites were significantly increased, with the latter being correlated (R2=0.71, p<0.001) with the decrement in DLNO. We conclude that DLNO and, to a lesser extent, DLCO are compromised before HSCT mainly due to a DM,CO reduction. A further reduction of DM,CO without VC loss occurs after HSCT, possibly related to development of oedema, or interstitial fibrosis, or both.

  14. Nitric oxide diffusing capacity versus spirometry in the early diagnosis of emphysema in smokers.

    PubMed

    van der Lee, I; Gietema, H A; Zanen, P; van Klaveren, R J; Prokop, M; Lammers, J-W J; van den Bosch, J M M

    2009-12-01

    The diffusion capacity for nitric oxide (DLNO) is independent of pulmonary capillary blood volume and equals the membrane diffusing capacity. Therefore the DLNO could be more sensitive in detecting alveolar destruction than the DLCO. We measured flow-volumes curves, DLNO, DLCO, the transfer coefficients KNO (DLNO/VA) and KCO (DLCO/VA) and performed computed tomography (CT) scans in 263 randomly selected heavy smokers. Subjects with areas > or =1% of the total lung volume showing an attenuation <-950 Hounsfield Units were considered to have emphysema. In 36 subjects emphysema was diagnosed with CT, a low KNO was present in 94 subjects, and in 95 subjects a FEV1/FVC ratio <70% was seen. The area under the ROC curve for detection CT-based emphysema was 0.894 for the KNO, 0.822 for the KCO and 0.795 for FEV1/FVC, meaning that the KNO has a slightly higher sensitivity to detect emphysema than the KCO and FEV1/FVC. The positive predictive value of KNO however was low (34.7%), while the negative predictive value of KNO was very high (98.2%), indicating an emphysema exclusion test. The DLNO/DLCO ratio is significantly higher in the study group compared to normal subjects.

  15. Structure-function correlation in the human placenta: the morphometric diffusing capacity for oxygen at full term.

    PubMed Central

    Mayhew, T M; Joy, C F; Haas, J D

    1984-01-01

    A combination of stereology and physiology is used to estimate the morphometric diffusing capacity for oxygen of the normal human placenta at term. The morphometric diffusing capacity is found to be higher than published values determined by physiological methods. The most likely explanation for this discrepancy is that physiological values are too low because of the effects of shunts, placental oxygen consumption and uneven diffusion:perfusion ratios. Despite the discrepancy, morphometry of histological sections offers a valuable and practicable alternative for comparing the functional potential of the placenta in different species, during normal gestation, disease, experimental treatment and environmental hypoxic stress. Images Fig. 2 PMID:6526720

  16. Trap-governed hydrogen diffusivity and uptake capacity in ultrahigh-strength AERMET 100 steel

    NASA Astrophysics Data System (ADS)

    Thomas, Richard L. S.; Li, Daoming; Gangloff, Richard P.; Scully, John R.

    2002-07-01

    The hydrogen-uptake capacity and mobility in ultrahigh-strength AERMET 100 are characterized for various electrochemical charging and baking conditions. From thermal desorption spectroscopy, the apparent hydrogen diffusivity ( D H < 3 × 10-8 cm2/s at 23 °C) is over tenfold less than the values typical of tempered martensitic steels such as AISI 4130. The value of D H decreases with decreasing temperature below 200 °C, with a relatively high apparent activation energy for diffusion of 17.7 to 18.8 ± 0.2 kJ/mol at the 95 pct confidence level. The value of D H also decreases with decreasing diffusible H concentration from less-severe charging or increased baking. Potentiostatic charging in saturated Ca(OH)2 produced total and diffusible H concentrations in AERMET 100 which increase with (H+/H) overpotential and are significantly higher than results for AISI 4130 steel under the same conditions. A significant H concentration was produced by zero overpotential deposition. These characteristics are explained by extensive reversible and irreversible H trapping involving at least three unique trap states in the ultrafine AERMET 100 microstructure. The former likely include coherent M2C carbides, soluble Ni, or precipitated austenite, and the latter include larger incoherent M x C y or martensite lathed-packet interfaces. Baking at 23 °C and 200 °C removes H from the lowest binding-energy sites, but results in reduced D H levels to prolong outgassing time. Additionally, substantial H was retained in stronger trap states. These trapping effects are pertinent to hydrogen embrittlement of AERMET 100 steel.

  17. Carbon monoxide intoxication.

    PubMed

    Bleecker, Margit L

    2015-01-01

    Carbon monoxide (CO) is a colorless, odorless, nonirritant gas that accounts for numerous cases of CO poisoning every year from a variety of sources of incomplete combustion of hydrocarbons. These include poorly functioning heating systems, indoor propane-powered forklifts, indoor burning of charcoal burning briquettes, riding in the back of pick-up trucks, ice skating rinks using propane-powered resurfacing machines, and gasoline-powered generators that are not in correct locations. Once CO is inhaled it binds with hemoglobin to form carboxyhemoglobin (COHb) with an affinity 200 times greater than oxygen that leads to decreased oxygen-carrying capacity and decreased release of oxygen to tissues leading to tissue hypoxia. Ischemia occurs with CO poisoning when there is loss of consciousness that is accompanied by hypotension and ischemia in the arterial border zones of the brain. Besides binding to many heme-containing proteins, CO disrupts oxidative metabolism leading to the formation of free radicals. Once hypotension and unconsciousness occur with CO poisoning, lipid peroxidation and apoptosis follow. Because COHb has a short half-life, examination of other biomarkers of CO neurotoxicity that reflect inflammation or neuronal damage has not demonstrated consistent results. The initial symptoms with CO exposure when COHb is 15-30% are nonspecific, namely, headache, dizziness, nausea, fatigue, and impaired manual dexterity. However individuals with ischemic heart disease may experience chest pain and decreased exercise duration at COHb levels between 1% and 9%. COHb levels between 30% and 70% lead to loss of consciousness and eventually death. Following resolution of acute symptoms there may be a lucid interval of 2-40 days before the development of delayed neurologic sequelae (DNS), with diffuse demyelination in the brain accompanied by lethargy, behavior changes, forgetfulness, memory loss, and parkinsonian features. Seventy-five percent of patients with DNS

  18. Lung diffusing capacity for nitric oxide at lowered and raised ambient pressures.

    PubMed

    Linnarsson, Dag; Hemmingsson, Tryggve E; Frostell, Claes; Van Muylem, Alain; Kerckx, Yannick; Gustafsson, Lars E

    2013-12-01

    Lung diffusing capacity for NO (DLNO) was determined in eight subjects at ambient pressures of 505, 1015, and 4053hPa (379, 761 and 3040mmHg) as they breathed normoxic gases. Mean values were 116.9±11.1 (SEM), 113.4±11.1 and 99.3±10.1mlmin(-1)hPa(-1)at 505, 1015, and 4053hPa, with a 13% difference between the two higher pressures (P=0.017). The data were applied to a model with two serially coupled conductances; the gas phase (DgNO, variable with pressure), and the alveolo-capillary membrane (DmNO, constant). The data fitted the model well and we conclude that diffusive transport of NO in the peripheral lung is inversely related to gas density. At normal pressure DmNO was approximately 5% larger than DLNO, suggesting that the Dg factor then is not negligible. We also conclude that the density of the breathing gas is likely to impact the backdiffusion of naturally formed NO from conducting airways to the alveoli.

  19. Cerebrovascular ischaemia after carbon monoxide intoxication.

    PubMed

    Kara, Hasan; Bayir, A; Ak, Ahmet; Degirmenci, Selim

    2015-02-01

    Carbon monoxide intoxication is the most prevalent cause of death from carbon monoxide poisoning. We herein report the case of a 56-year-old man who was found unconscious and smelled of smoke after exposure to carbon monoxide from a heater. He scored 5 on the Glasgow Coma Scale, and had respiratory insufficiency and elevated troponin I, creatine kinase-MB fraction and carboxyhaemoglobin levels. He was treated by mechanical ventilation. After regaining consciousness, brain magnetic resonance imaging showed diffusion restriction in the left occipital lobe; there was a loss of vision (right temporal hemianopsia), which improved by the follow-up session. Carbon monoxide intoxication may cause neurologic and cardiac sequelae, and the initial treatment includes oxygen therapy. Acute carbon monoxide poisoning can cause serious injury to the brain, heart and other organs; the most severe damages that could be inflicted to the brain include cerebral ischaemia and hypoxia, oedema, and neural cell degeneration and necrosis. PMID:25715861

  20. Cerebrovascular ischaemia after carbon monoxide intoxication.

    PubMed

    Kara, Hasan; Bayir, A; Ak, Ahmet; Degirmenci, Selim

    2015-02-01

    Carbon monoxide intoxication is the most prevalent cause of death from carbon monoxide poisoning. We herein report the case of a 56-year-old man who was found unconscious and smelled of smoke after exposure to carbon monoxide from a heater. He scored 5 on the Glasgow Coma Scale, and had respiratory insufficiency and elevated troponin I, creatine kinase-MB fraction and carboxyhaemoglobin levels. He was treated by mechanical ventilation. After regaining consciousness, brain magnetic resonance imaging showed diffusion restriction in the left occipital lobe; there was a loss of vision (right temporal hemianopsia), which improved by the follow-up session. Carbon monoxide intoxication may cause neurologic and cardiac sequelae, and the initial treatment includes oxygen therapy. Acute carbon monoxide poisoning can cause serious injury to the brain, heart and other organs; the most severe damages that could be inflicted to the brain include cerebral ischaemia and hypoxia, oedema, and neural cell degeneration and necrosis.

  1. The predictive capacity of apparent diffusion coefficient (ADC) in response assessment of brain metastases following radiation.

    PubMed

    Jakubovic, Raphael; Zhou, Stephanie; Heyn, Chris; Soliman, Hany; Zhang, Liyang; Aviv, Richard; Sahgal, Arjun

    2016-03-01

    To investigate the predictive capacity of the apparent diffusion coefficient (ADC) as a biomarker of radiation response in brain metastases. Seventy brain metastases from 42 patients treated with either stereotactic radiosurgery or whole brain radiotherapy were imaged at baseline, 1 week, and 1 month post-treatment using diffusion-weighted MRI. Mean and median relative ADC for metastases was calculated by normalizing ADC measurements to baseline ADC. At 1 year post-treatment, or last available follow-up MRI, volume criteria determined final tumour response status. Uni- and multivariate analysis was used to account for factors associated with tumour response at 1 week and 1 month. A generalized estimating equations model took into consideration multiple tumours per subject. Optimal thresholds that distinguished responders from non-responders, as well as sensitivity and specificity were determined by receiver operator characteristic analysis and Youden's index. Lower relative ADC values distinguished responders from non-responders at 1 week and 1 month (P < 0.05). Optimal cut-off values for response were 1.060 at 1 week with a sensitivity and specificity of 75.0 and 56.3 %, respectively. At 1 month, the cut-off was 0.971 with a sensitivity and specificity of 70.0 and 68.8 %, respectively. A multivariate general estimating equations analysis identified no prior radiation [odds ratio (OR) 0.211 and 0.137, P = 0.033 and 0.0177], and a lower median relative ADC at 1 week and 1 month (OR 0.619 and 0.694, P = 0.0036 and 0.005), as predictors of tumour response. Lower relative ADC values at 1 week and 1 month following radiation distinguished responders from non-responders and may be a promising biomarker of early radiation response.

  2. Effects of environmental O2 on blood flow and diffusing capacity in amphibian skin.

    PubMed

    Malvin, G M; Hlastala, M P

    1989-05-01

    The effects of local environmental PO2 on cutaneous blood flow (Q) and the membrane diffusing capacity of the skin (D) were investigated in the leopard frog, Rana pipiens, and the lungless salamander, Desmognathus quadramaculatus. Halothane anesthetized animals were equilibrated with Freon-22 (Fr) and acetylene (Ac) in a box. A gas mixture containing either 0, 20 or 40% O2, respectively, in N2 and initially free of Fr and Ac was drawn through a small sample chamber on the abdomen. The excretion of Fr and Ac into the chamber was analyzed with a mass spectrometer. These conditions allowed the determination of the cutaneous conductance to Fr (GFr) and Ac (GAc) at the 3 levels of local environmental O2. GFr and GAc of the isolated skin and the blood solubilities of the 2 gases were also determined. To estimate Q, DAc and DFr, the data were analyzed with a homogeneous single capillary model. In the frog, Q varied directly with sample chamber [O2], but chamber [O2] had no effect on D. In the salamander, O2 had no effect on either Q or D. The results indicate that regulation of cutaneous gas exchange in the frog by local environmental O2 only involves alterations in Q. Similar control of cutaneous gas exchange is absent in the lungless salamander.

  3. Change in Diffusing Capacity After Radiation as an Objective Measure for Grading Radiation Pneumonitis in Patients Treated for Non-Small-Cell Lung Cancer

    SciTech Connect

    Lopez Guerra, Jose Luis; Gomez, Daniel; Zhuang Yan; Levy, Lawrence B.; Eapen, George; Liu Hongmei; Mohan, Radhe; Komaki, Ritsuko; Cox, James D.; Liao Zhongxing

    2012-08-01

    Purpose: Scoring of radiation pneumonitis (RP), a dose-limiting toxicity after thoracic radiochemotherapy, is subjective and thus inconsistent among studies. Here we investigated whether the extent of change in diffusing capacity of the lung for carbon monoxide (DLCO) after radiation therapy (RT) for non-small-cell lung cancer (NSCLC) could be used as an objective means of quantifying RP. Patients and Methods: We analyzed potential correlations between DLCO and RP in 140 patients who received definitive RT ({>=}60 Gy) with or without chemotherapy for primary NSCLC. All underwent DLCO analysis before and after RT. Post-RT DLCO values within 1 week of the RP diagnosis (Grade 0, 1, 2, or 3) were selected and compared with that individual's preradiation values. Percent reductions in DLCO and RP grade were compared by point biserial correlation in the entire patient group and in subgroups stratified according to various clinical factors. Results: Patients experiencing Grade 0, 1, 2, or 3 RP had median percentage changes in DLCO after RT of 10.7%, 13%, 22.1%, or 35.2%. Percent reduction in DLCO correlated with RP Grade {<=}1 vs. {>=}2 (p = 0.0004). This association held for the following subgroups: age {>=}65 years, advanced stage, smokers, use of chemotherapy, volume of normal lung receiving at least 20 Gy {>=}30%, and baseline DLCO or forced expiratory volume in 1 second {>=}60%. Conclusions: By correlating percent change in DLCO from pretreatment values at the time of diagnosis of RP with RP grade, we were able to identify categories of RP based on the change in DLCO. These criteria provide a basis for an objective scoring system for RP based on change in DLCO.

  4. Reference values of pulmonary diffusing capacity for nitric oxide in an adult population.

    PubMed

    Zavorsky, Gerald S; Cao, Jiguo; Murias, Juan M

    2008-02-01

    Our objective was to create reference values for single-breath DLNO based on a sample of non-smoking healthy males and females using a short breath-hold time. The sample included 130 individuals varied in age (18-85 yr), height (149-190 cm), and weight (49.4-102.6 kg). The subjects performed single-breath-hold maneuvers at rest inhaling 41 +/- 6 ppm NO and a standard diffusion mixture. The breath-hold time was 5.5 +/ -0.6 s. Multiple linear regression with backward elimination of the independent variables age, weight, gender, and either measured lung volume (called alveolar volume or VA) or height revealed specific prediction equations for DLNO. Inserting VA instead of height into the regression equation determined how much of an abnormality of DLNO was due to gas exchange versus low lung volume. The predicted DLNO adjusted for lung volume (ml/min/mmHg) = DLNO = 73.1 + 17.26 x (VA)+17.56 x (gender) - 1.0 x (age). The predicted DLNO unadjusted for lung volume (ml/min/mmHg) = -20.1 + 1.167 x (height)+31.81 x (gender) - 1.21 x (age). For gender, 1 = males, 0 = females; VA = liters; height = cm. Age, gender and VA (lung volume) were the best predictors of DLNO and DLCO. Weight was not a good independent predictor of DLNO or DLCO. When normalizing for height and age, women have 650 ml lower forced vital capacity, 660 ml lower VA, and a 6 and 32 ml/min/mmHg lower DLCO and DLNO, respectively, compared to men. Normalizing for lung volume and age, women have, on average, a 3.2 and 18 ml/min/mmHg lower DLCO and DLNO, respectively, compared to men.

  5. Dynamic modelling of the effects of ion diffusion and side reactions on the capacity loss for vanadium redox flow battery

    NASA Astrophysics Data System (ADS)

    Tang, Ao; Bao, Jie; Skyllas-Kazacos, Maria

    The diffusion of vanadium ions across the membrane along with side reactions can have a significant impact on the capacity of the vanadium redox flow battery (VFB) over long-term charge-discharge cycling. Differential rates of diffusion of the vanadium ions from one half-cell into the other will facilitate self-discharge reactions, leading to an imbalance between the state-of-charge of the two half-cell electrolytes and a subsequent drop in capacity. Meanwhile side reactions as a result of evolution of hydrogen or air oxidation of V 2+ can further affect the capacity of the VFB. In this paper, a dynamic model is developed based on mass balances for each of the four vanadium ions in the VFB electrolytes in conjunction with the Nernst Equation. This model can predict the capacity as a function of time and thus can be used to determine when periodic electrolyte remixing or rebalancing should take place to restore cell capacity. Furthermore, the dynamic model can be potentially incorporated in the control system of the VFB to achieve long term optimal operation. The performance of three different types of membranes is studied on the basis of the above model and the simulation results together with potential operational issues are analysed and discussed.

  6. Postural variation of pulmonary diffusing capacity as a marker of lung microangiopathy in Indian patients with type 2 diabetes mellitus

    PubMed Central

    Kumar, Avinash; Bade, Geetanjali; Trivedi, Anjali; Jyotsna, Viveka P.; Talwar, Anjana

    2016-01-01

    Introduction: Diabetes mellitus (DM) is characterized by the presence of chronic hyperglycemia and formation of advanced glycation end products (AGEs). Interaction between AGE and its receptor leads to endothelial damage and microangiopathy. This study was undertaken to investigate the possibility of using a postural variation of diffusing capacity as an early marker of lung microangiopathy and its correlation with the level of adhesion molecules, HbA1c, duration of diabetes, and insulin resistance in type 2 DM (T2DM) patients with and without microangiopathy. Materials and Methods: Forty patients having T2DM without any microangiopathy (n = 20) as well as with microangiopathy (n = 20), and 22 age and sex matched healthy controls were enrolled in this cross-sectional study. Measurement of lung volumes and capacities were done. DLco was measured in sitting and supine position. Levels of vascular cell adhesion molecule-1 (VCAM-1), E-selectin, fasting glucose, and insulin were estimated in plasma of the patients and compared with controls. Results: Restrictive type of ventilatory change was observed in DM patients. Diffusing capacity (% predicted) in the supine position (P < 0.0001), postural change in DLco (P < 0.0001), and coefficient of diffusion were significantly less in DM patients as compared to controls. Plasma levels of VCAM-1 were significantly higher in DM patients without microangiopathy and negatively correlated (r = −0.4054, P = 0.0094) with Δ DLco in all diabetic subjects. All patients had significantly higher insulin resistance. Conclusion: Lack of postural increase in diffusing capacity in type 2 diabetic patients along with increased VCAM-1 levels could reflect the presence of an early microangiopathy of the small pulmonary vessels. PMID:27042422

  7. Carbon monoxide in rainwater.

    PubMed

    Swinnerton, J W; Lamontagne, R A; Linnenbom, V J

    1971-05-28

    Concentrations of carbon monoxide in rainwater collected at widely diverse locations show up to a 200-fold supersaturation relative to the partial pressure of the gas in the atmosphere. These results indicate the existence of an additional natural source of carbon monoxide not heretofore considered. Production of carbon monoxide in clouds is tentatively attributed to the photochemical oxidation of organic matter or the slight dissociation of carbon dioxide induced by electrical discharges, or both. Methane concentrations measured in the same rainwater show that the partitioning of this gas, unlike that of carbon monoxide, is very close to a state of equilibrium.

  8. Carbon Monoxide Toxicity

    PubMed Central

    Aniol, Michael J.

    1992-01-01

    Of all fatal poisonings in the United States, an estimated half are due to carbon monoxide. The number of non-lethal poisonings due to carbon monoxide is difficult to estimate because signs and symptoms of carbon monoxide poisoning cover a wide spectrum and mimic other disorders. Misdiagnosis is serious, as the patient often returns to the contaminated environment. Those not receiving proper treatment are at significant risk, as high as 10% to 12%, of developing late neurological sequelae. The diagnosis of carbon monoxide poisoning depends upon precise history taking, careful physical examination, and a high index of suspicion. ImagesFigure 2 PMID:21221282

  9. Total Antioxidant Capacity of Serum Determined Using the Potassium Permanganate Agar Method Based on Serum Diffusion in Agar

    PubMed Central

    Zhou, Ying; Zhang, Meijuan; Liu, Hui

    2015-01-01

    Objectives. To develop a new method for determining total antioxidants in serum and to evaluate the total antioxidant capacity of organisms. Design and Methods. Sodium hyposulfite (Na2S2O3) and serum were used to evaluate the linearity and precision of the potassium permanganate agar method. The area of serum diffusion in samples from 30 intensive care unit (ICU) patients compared with 44 healthy subjects was determined by the potassium permanganate agar method. Results. The linearity (R2 in the linear experiment of Na2S2O3 was 0.994; R2 in the linear experiment of serum was 0.987) and precision (coefficient of variation of area of high level serum diffusion within-run, between-run, and between-day and coefficient of variation of area of low serum diffusion within-run, between-run, and between-day were all less than 10%) were acceptable using the potassium permanganate agar method. Total antioxidants of serum between the ICU group and the healthy group were different (p = 0.002, two tailed). Conclusions. Total antioxidants in serum can be determined by the potassium permanganate agar method. The total antioxidant capacity of an organism can be evaluated by the amount of total antioxidants in serum. PMID:26347595

  10. Multigenerational Effects of Rearing Atmospheric Oxygen Level on the Tracheal Dimensions and Diffusing Capacities of Pupal and Adult Drosophila melanogaster.

    PubMed

    Klok, C Jaco; Kaiser, Alexander; Socha, John J; Lee, Wah-Keat; Harrison, Jon F

    2016-01-01

    Insects are small relative to vertebrates, and were larger in the Paleozoic when atmospheric oxygen levels were higher. The safety margin for oxygen delivery does not increase in larger insects, due to an increased mass-specific investment in the tracheal system and a greater use of convection in larger insects. Prior studies have shown that the dimensions and number of tracheal system branches varies inversely with rearing oxygen in embryonic and larval insects. Here we tested whether rearing in 10, 21, or 40 kPa atmospheric oxygen atmospheres for 5-7 generations affected the tracheal dimensions and diffusing capacities of pupal and adult Drosophila. Abdominal tracheae and pupal snorkel tracheae showed weak responses to oxygen, while leg tracheae showed strong, but imperfect compensatory changes. The diffusing capacity of leg tracheae appears closely matched to predicted oxygen transport needs by diffusion, perhaps explaining the consistent and significant responses of these tracheae to rearing oxygen. The reduced investment in tracheal structure in insects reared in higher oxygen levels may be important for conserving tissue PO2 and may provide an important mechanism for insects to invest only the space and materials necessary into respiratory structure. PMID:27343104

  11. Multigenerational Effects of Rearing Atmospheric Oxygen Level on the Tracheal Dimensions and Diffusing Capacities of Pupal and Adult Drosophila melanogaster.

    PubMed

    Klok, C Jaco; Kaiser, Alexander; Socha, John J; Lee, Wah-Keat; Harrison, Jon F

    2016-01-01

    Insects are small relative to vertebrates, and were larger in the Paleozoic when atmospheric oxygen levels were higher. The safety margin for oxygen delivery does not increase in larger insects, due to an increased mass-specific investment in the tracheal system and a greater use of convection in larger insects. Prior studies have shown that the dimensions and number of tracheal system branches varies inversely with rearing oxygen in embryonic and larval insects. Here we tested whether rearing in 10, 21, or 40 kPa atmospheric oxygen atmospheres for 5-7 generations affected the tracheal dimensions and diffusing capacities of pupal and adult Drosophila. Abdominal tracheae and pupal snorkel tracheae showed weak responses to oxygen, while leg tracheae showed strong, but imperfect compensatory changes. The diffusing capacity of leg tracheae appears closely matched to predicted oxygen transport needs by diffusion, perhaps explaining the consistent and significant responses of these tracheae to rearing oxygen. The reduced investment in tracheal structure in insects reared in higher oxygen levels may be important for conserving tissue PO2 and may provide an important mechanism for insects to invest only the space and materials necessary into respiratory structure.

  12. Factors affecting expired waveform for carbon monoxide

    SciTech Connect

    Rubin, D.Z.; Lewis, S.M.; Mittman, C.

    1984-01-01

    The authors previously presented a method based on a computer lung model for determining the distribution of both specific ventilation and specific diffusing capacity. These argon and carbon monoxide (CO) washin and washout studies were obtained in 12 normal subjects and 24 patients with varying degrees of obstructive lung disease. In addition to end-tidal and mixed expired gas concentrations, the expired waveform for both gases was sampled. In patients we found that this method failed to adequately describe CO dynamics during the early part of expiration; predicted concentrations were higher than actual data. Modifications of the original model that satisfy all data are presented. This new model suggests that CO uptake occurs in spaces with ventilatory properties of dead space. The accuracy and reliability of these observations were established by computer simulation studies as well as by repeated testing in one subject. These proved to be highly reproducible over a period of 5 mo. Standard parameter sensitivity tests showed parameters to vary by less than 10% and to be stable even when realistic levels of noise were added to the data. We conclude that studies involving ventilation of insoluble gases are insufficient to describe gas exchange in the lung. The addition of an exchangeable gas adds significant understanding of lung function, particularly in disease.

  13. Adjustments of the oxygen diffusing capacity to energetic demands during the development of the quail (Coturnix coturnix japonica).

    PubMed

    Canals, M; Martinez, B B; Figueroa, D; Sabat, P

    2011-07-01

    One of the hypotheses that attempt to explain physiological limitations of energy budgets is the symmorphosis hypothesis, which proposes that if matching structures to functional needs were combined with the strict economy of energy and materials, the result would be an optimal organ design for the specific function it serves. Evidence in favor of symmorphosis in adults is as abundant as evidence against it, but the plasticity of some morphological traits may be dependent on the ontogenetic stage at which acclimation acts. Thus, here we studied the adjustment of structure and function in lungs at different stages of development in the quail Coturnix coturnix japonica under two thermal regimes. Our main results show that i) resting metabolic rate, maximum thermogenic oxygen consumption and oxygen diffusion capacity did not exhibit developmental plasticity for two thermal environments; and ii) oxygen diffusion capacity fully adjusted to resting metabolic rate and maximum oxygen consumption during development. C. coturnix has a low safety factor close to 1 which is consistent with the symmorphosis hypothesis.

  14. Estimating carbon monoxide exposure

    NASA Technical Reports Server (NTRS)

    Edgerley, R. H.

    1971-01-01

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

  15. Carbon Monoxide Poisoning

    MedlinePlus

    ... colorless gas created when fuels (such as gasoline, wood, coal, natural gas, propane, oil, and methane) burn incompletely. ** Carbon Monoxide can have different effects on people based on its concentration in the ...

  16. Red cell CO partial pressure during CO uptake; implications for CO diffusing capacity

    SciTech Connect

    Reeves, R.B.; Hae Kun Park )

    1991-03-11

    The authors used the naked thin blood film technique of Heidelberger and Reeves for measuring gas uptake kinetics to test the hypothesis that intracellular CO partial pressure (P{sub e}) is in equilibrium with Co partial pressure around the cell (P{sub c}) during CO uptake by the CO for O{sub 2} displacement reaction. Only if P{sub e} = P{sub c} will observed initial CO uptake rates be predicted by the Gibson-Roughton equation: ({Delta}S/{Delta}t){sup {minus}1} = 2.54 {times} 10{sup {minus}2} + .0945 (P{sub o2}/P{sub co}), where S is COHb saturation. Using combinations of P{sub co} values of 2.1, 7, 21 and 70 Torr and P{sub o2} values of 100, 153, 214, 285, and 428 Torr, ({Delta}S/{Delta}t) was determined for 19 gas tension ratios. The weighted least squares regression line slope was not different from theoretical. The authors conclude that diffusion equilibrium is reached early in the CO uptake process. Therefore, the classical Bohr-Krogh assumption that P{sub co} {approx} 0 during CO uptake is in error and that all published values of D{sub Lco} are underestimates.

  17. Calculation of thermal conductivity, thermal diffusivity and specific heat capacity of sedimentary rocks using petrophysical well logs

    NASA Astrophysics Data System (ADS)

    Fuchs, Sven; Balling, Niels; Förster, Andrea

    2015-12-01

    In this study, equations are developed that predict for synthetic sedimentary rocks (clastics, carbonates and evapourates) thermal properties comprising thermal conductivity, specific heat capacity and thermal diffusivity. The rock groups are composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities of 0-30 per cent. Petrophysical properties and their well-logging-tool-characteristic readings were assigned to these rock-forming minerals and to pore-filling fluids. Relationships are explored between each thermal property and other petrophysical properties (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) using multivariate statistics. The application of these relations allows computing continuous borehole profiles for each rock thermal property. The uncertainties in the prediction of each property vary depending on the selected well-log combination. Best prediction is in the range of 2-8 per cent for the specific heat capacity, of 5-10 per cent for the thermal conductivity, and of 8-15 for the thermal diffusivity, respectively. Well-log derived thermal conductivity is validated by laboratory data measured on cores from deep boreholes of the Danish Basin, the North German Basin, and the Molasse Basin. Additional validation of thermal conductivity was performed by comparing predicted and measured temperature logs. The maximum deviation between these logs is <3 °C. The thermal-conductivity calculation allowed an evaluation of the depth range in which the palaeoclimatic effect on the subsurface temperature field can be observed in the North German Basin. This effect reduces the surface heat-flow density by 25 mW m-2.

  18. Morphological Pulmonary Diffusion Capacity for Oxygen of Burmese Pythons (Python molurus): a Comparison of Animals in Healthy Condition and with Different Pulmonary Infections.

    PubMed

    Starck, J M; Weimer, I; Aupperle, H; Müller, K; Marschang, R E; Kiefer, I; Pees, M

    2015-11-01

    A qualitative and quantitative morphological study of the pulmonary exchange capacity of healthy and diseased Burmese pythons (Python molurus) was carried out in order to test the hypothesis that the high morphological excess capacity for oxygen exchange in the lungs of these snakes is one of the reasons why pathological processes extend throughout the lung parenchyma and impair major parts of the lungs before clinical signs of respiratory disease become apparent. Twenty-four Burmese pythons (12 healthy and 12 diseased) were included in the study. A stereology-based approach was used to quantify the lung parenchyma using computed tomography. Light microscopy was used to quantify tissue compartments and the respiratory exchange surface, and transmission electron microscopy was used to measure the thickness of the diffusion barrier. The morphological diffusion capacity for oxygen of the lungs and the anatomical diffusion factor were calculated. The calculated anatomical diffusion capacity was compared with published values for oxygen consumption of healthy snakes, and the degree to which the exchange capacity can be obstructed before normal physiological function is impaired was estimated. Heterogeneous pulmonary infections result in graded morphological transformations of pulmonary parenchyma involving lymphocyte migration into the connective tissue and thickening of the septal connective tissue, increasing thickness of the diffusion barrier and increasing transformation of the pulmonary epithelium into a columnar pseudostratified or stratified epithelium. The transformed epithelium developed by hyperplasia of ciliated cells arising from the tip of the faveolar septa and by hyperplasia of type II pneumocytes. These results support the idea that the lungs have a remarkable overcapacity for oxygen consumption and that the development of pulmonary disease continuously reduces the capacity for oxygen consumption. However, due to the overcapacity of the lungs, this

  19. Transmissivity of carbon monoxide

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

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

  20. The photosynthetic capacity in 35 ferns and fern allies: mesophyll CO2 diffusion as a key trait.

    PubMed

    Tosens, Tiina; Nishida, Keisuke; Gago, Jorge; Coopman, Rafael Eduardo; Cabrera, Hernán Marino; Carriquí, Marc; Laanisto, Lauri; Morales, Loreto; Nadal, Miquel; Rojas, Roke; Talts, Eero; Tomas, Magdalena; Hanba, Yuko; Niinemets, Ülo; Flexas, Jaume

    2016-03-01

    Ferns and fern allies have low photosynthetic rates compared with seed plants. Their photosynthesis is thought to be limited principally by physical CO2 diffusion from the atmosphere to chloroplasts. The aim of this study was to understand the reasons for low photosynthesis in species of ferns and fern allies (Lycopodiopsida and Polypodiopsida). We performed a comprehensive assessment of the foliar gas-exchange and mesophyll structural traits involved in photosynthetic function for 35 species of ferns and fern allies. Additionally, the leaf economics spectrum (the interrelationships between photosynthetic capacity and leaf/frond traits such as leaf dry mass per unit area or nitrogen content) was tested. Low mesophyll conductance to CO2 was the main cause for low photosynthesis in ferns and fern allies, which, in turn, was associated with thick cell walls and reduced chloroplast distribution towards intercellular mesophyll air spaces. Generally, the leaf economics spectrum in ferns follows a trend similar to that in seed plants. Nevertheless, ferns and allies had less nitrogen per unit DW than seed plants (i.e. the same slope but a different intercept) and lower photosynthesis rates per leaf mass area and per unit of nitrogen.

  1. Solid State Carbon Monoxide Sensor

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

  2. [Pulmonary diffusion test to NO and CO time course during thoracic radiotherapy for lung cancer: the CONORT prospective study protocol].

    PubMed

    Zarza, V; Couraud, S; Hassouni, A; Prévost, C; Souquet, P-J; Letanche, G; Hammou, Y; Girard, N; Viart-Ferber, C; Mornex, F

    2014-10-01

    Thoracic radiotherapy is a usual treatment for lung cancer. Early-stages may be treated in stereotactic mode while locally advanced stages are usually treated with conventional radiotherapy mode. Pulmonary function tests show that thoracic irradiation has no impact on lung volume such as forced expiratory volume in one second (FEV1) or forced vital capacity (FCV). However, some studies found that CO (carbon monoxide) diffusing capacity (TLCO) may be altered under thoracic radiotherapy. DLCO alteration is usually symptomatic of either a lesion in the alveolar membrane or a pulmonary capillary alteration. Pulmonary diffusion may be also appreciated by the NO (azote monoxide) diffusion capacity. Moreover, using a double measurement of NO and CO diffusing capacities permit to assess which lung compartment (capillary or membrane) is affected. CONORT is an observational prospective monocentric study, aiming to assess the CO and NO diffusing capacity (as well as other pulmonary function tests) during thoracic radiotherapy. Inclusion criteria are patients with lung cancer, treated by thoracic radiotherapy (conformational or stereotactic), who signed consent. Pulmonary function tests are performed before, during, at the end and six weeks and six months after thoracic irradiation. To estimate a difference of 15% in diffusing capacity test, we have to include 112 patients with a 90% power and a 5% alpha risk. Four months after beginning, 36 patients were included. Preliminary data will be presented at the SFRO meeting.

  3. Analysis of Carbon Monoxide in Blood

    NASA Astrophysics Data System (ADS)

    Huddle, Benjamin P.; Stephens, Joseph C.

    2003-04-01

    Forensic tests used to perform the qualitative and quantitative analyses of carbon monoxide in blood are described. The qualitative test uses the diffusion of CO, which is released from blood by reaction with H2SO4, into a PdCl2 solution in a Conway cell and the resultant formation of a palladium mirror. The quantitative analysis is based on the absorption of visible light by carboxyhemoglobin at 541 nm and reduced hemoglobin at 555 nm. Both procedures are suitable for undergraduate chemistry experiments.

  4. Disulfur monoxide: production by Desulfovibrio.

    PubMed

    Iverson, W P

    1967-05-26

    Desulfovibrio desulfuricans growing on agar surfaces produces a gas that appears to be identical to "Schenk's sulfur monoxide," which was later identified as disulfur monoxide The gas stimulates surface growth of Desulfovibrio on an agar medium and is used by the cells as an electron donor for the reduction of benzyl viologen.

  5. Carbon Monoxide Sensor

    NASA Technical Reports Server (NTRS)

    1978-01-01

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

  6. [Acute carbon monoxide poisoning].

    PubMed

    Raphaël, Jean-Claude

    2008-04-30

    Carbon monoxide (CO) poisoning is still complicated by a high mortality and morbidity rate. Diagnosis can be obvious but is most of time difficult and sometimes remained unknown. It is usually based on clinical signs and must be confirmed by assessment of CO level in room air or in patient's expired breathing or blood and detection of a source. Mild neurological sequelae are very common. Normobaric oxygen is the first line treatment. Comatose and pregnant patients must undergo hyperbaric oxygen. All CO poisoning has to be declared to sanitary authority, which will in turn conduct a technical inspection to remove the source. The patient must be informed that he is at risk of new poisoning and of neurological complications. Progress in prevention and research in therapeutics are needed in order to reduce CO related morbidity.

  7. Carbon monoxide: Anticoagulant or procoagulant?

    PubMed

    Nielsen, Vance G; Pretorius, Etheresia

    2014-03-01

    Within the past decade there have been several investigations attempting to define the impact of exogenous and endogenous carbon monoxide exposure on hemostasis. Critically, two bodies of literature have emerged, with carbon monoxide mediated platelet inhibition cited as a cause of in vitro human and in vitro/in vivo rodent anticoagulation. In contrast, interaction with heme groups associated with fibrinogen, α₂-antiplasmin and plasmin by carbon monoxide has resulted in enhanced coagulation and decreased fibrinolysis in vitro in human and other species, and in vivo in rabbits. Of interest, the ultrastructure of platelet rich plasma thrombi demonstrates an abnormal increase in fine fiber formation and matting that are obtained from humans exposed to carbon monoxide. Further, thrombi obtained from humans and rabbits have very similar ultrastructures, whereas mice and rats have more fine fibers and matting present. In sum, there may be species specific differences with regard to hemostatic response to carbon monoxide. Carbon monoxide may be a Janus-faced molecule, with potential to attenuate or exacerbate thrombophilic disease.

  8. [Carbon monoxide poisoning].

    PubMed

    Jaeger, K; Ruschulte, H; Heine, J; Piepenbrock, S

    2000-01-01

    Carbon monoxide (CO) is a product of incomplete burning of coals and carbon compounds and is a gas without any typical taste, colour or smell. Defective radiators or gas pipes, open fireplaces, fires and explosions are sources of unintended CO production and inhalation. CO bonds with haemoglobin much more readily than oxygen does. CO toxicity causes impaired oxygen delivery and utilisation at cellular level. It affects different sites within the body, but has its most profound impact on the organs with the highest oxygen requirement. CO concentration and the intensity and duration of inhalation determine the extent of intoxication. Following basic life support, assisted or controlled ventilation with 100% oxygen is essential during emergency care. Hyperbaric oxygenation (HBO) is the preferred therapeutic option for releasing CO from its binding to haemoglobin. It has been shown that CO may cause lipid peroxidation and leukocyte-mediated inflammatory changes in the brain, a process that may be inhibited by HBO. Patients with neurological symptoms including loss of consciousness and expectant mothers should undergo HBO treatment, no matter how high their CO levels are. Neonates and in-utero fetuses are more vulnerable due to the natural leftward shift of the dissociation curve of fetal haemoglobin, a lower baseline pO2 and carboxyhaemoglobin levels at equilibration that are 10-15% higher than maternal levels. Physicians need to be aware of the potential occurrence of this life threatening hazard so that appropriate emergency treatment can be administered and fatalities prevented. PMID:10920484

  9. Carbon monoxide in the home environment

    SciTech Connect

    Love, A.L.

    1986-01-01

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

  10. A review on engineering of cellulosic cigarette paper to reduce carbon monoxide delivery of cigarettes.

    PubMed

    Shen, Jing; Li, Jinsong; Qian, Xueren; Ren, Wanshan; Fatehi, Pedram

    2014-01-30

    In cigarette production, the cellulosic paper essentially derived from flax fibers or other fiber materials is used as the wrapping material. During smoking of cigarettes, the highly toxic carbon monoxide is produced. To decrease the amount of carbon monoxide emission in the mainstream smoke, the engineering of all cigarette components including cellulosic cigarette paper and tobacco column is critical. This review summarizes the concepts related to engineering of cigarette paper. These mainly include permeability control, increased use of burn additives, optimization of fiber basis weight, engineering of calcium carbonate fillers, and incorporation of catalysts/oxidants. In particular, catalytic and/or oxidative conversion of carbon monoxide to carbon dioxide has been very widely reported. The control of permeability/diffusivity of cigarette paper is also of critical importance for enhanced diffusion of carbon monoxide out of the cigarette. The development of new concepts and combination of various concepts may lead to breakthroughs in this area.

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

    SciTech Connect

    Turino, G.M.

    1981-01-01

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

  12. Effects of a Basketball Activity on Lung Capillary Blood Volume and Membrane Diffusing Capacity, Measured by NO/CO Transfer in Children.

    PubMed

    Dridi, Rim; Glenet, Stephane; Tabka, Zouhair; Amri, Mohamed; Guénard, Hervé

    2006-01-01

    In both children and adults, acute exercise increases lung capillary blood volume (Vc) and membrane factor (DmCO). We sought to determine whether basketball training affected this adaptation to exercise in children. The purpose of this study was to determine the effects of two years sport activity on the components of pulmonary gas transfer in children. Over a 2-yr period, we retested 60 nine year old boys who were initially separated in two groups: 30 basketball players (P) (9.0 ± 1.0 yrs; 35.0 ± 5.2 kg; 1.43 ± 0.05 m), and matched non players controls (C) (8.9 ± 1.0 yrs; 35.0 ± 6.0 kg; 1.44 ± 0.06 m) who did not perform any extracurricular activity, Vc and DmCO were measured by the NO/CO transfer method at rest and during sub-maximal exercise. Maximal aerobic power and peak power output was 12% higher in the trained group compared to matched controls (p < 0.05). Nitric oxide lung transfer (TLNO) per unit lung volume and thus, DmCO per unit of lung volume (VA) were higher at rest and during exercise in the group which had undergone regular basketball activity compared to matched controls (p < 0.05). Neither lung capillary blood volume nor total lung transfer for carbon monoxide (TLCO) were significantly different between groups. These results suggest that active sport can alter the properties of the lung alveolo-capillary membrane by improving alveolar membrane conductance in children. Key PointsTrained children had greater DmCO/VA and DmCO/Vc ratios compared with control children during exercise.The mechanisms by which basketball playing children were thought to improve lung diffusion are speculative.Further work will be required to determine the kinetics of the alteration in Dm when children switch from non players to players status or vice-versa.

  13. (Carbon monoxide metabolism by photosynthetic bacteria)

    SciTech Connect

    Not Available

    1989-01-01

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

  14. Role of reaction resistance in limiting carbon monoxide uptake in rabbit lungs.

    PubMed

    Heller, H; Schuster, K

    1998-06-01

    The contribution of reaction resistance to overall resistance to pulmonary carbon monoxide (CO) uptake [DLCO/(ThetaCO . Vc), where DLCO is lung CO diffusing capacity, ThetaCO is CO uptake conductance of erythrocytes, and Vc is pulmonary capillary blood volume] was determined in 10 anesthetized, paralyzed, and artificially ventilated rabbits. On the basis of the classical double-reciprocal equation of F. G. W. Roughton and R. E. Forster (J. Appl. Physiol. 11: 290-302, 1957), DLCO/(ThetaCO . Vc) was obtained by solving the relation DLCO/(ThetaCO . Vc) = 1 - 2/(DLNO/DLCO), where DLNO/DLCO represents the ratio between the respective single-breath diffusing capacities (DL) of nitric oxide (NO) and CO pulmonary capillary blood. The lungs of eight rabbits were inflated, starting from residual volume, by using 55 ml of indicator gas mixture (0.2% CO and 0.05% NO in nitrogen). DL values were calculated by taking the end-tidal partial pressures of CO and NO as analyzed by using a respiratory mass spectrometer. The overall value was DLCO/(ThetaCO . Vc) = 0.4 +/- 0.025 (mean +/- SD). Because of the use of O2-free indicator gas mixtures, the end-tidal O2 partial pressures were approximately 21 Torr. In one other rabbit, the application of 0.2% CO and 0.001% NO yielded DLCO/(ThetaCO . Vc) = 0.39; in the tenth rabbit, however, inspiratory volume was varied, and an identical value was found at functional residual capacity. We conclude that the contribution of reaction resistance to overall resistance to pulmonary CO uptake is independent of the inspiratory NO concentration used, including, with respect to the pertinent literature, the conclusion that in rabbits, dogs, and humans this contribution amounts to 40% when determined at functional residual capacity.

  15. Open air carbon monoxide poisoning.

    PubMed

    Jumbelic, M I

    1998-01-01

    An unusual manner of carbon monoxide poisoning claimed the lives of two adults in two separate incidents. In the first case, a young man was four wheeling in a swampy area when his jeep became stuck in the mud as he continued to floor the accelerator. Carbon monoxide fumes entered the vehicle through the rusted floorboards, killing the driver. In the second case, two teens were skinny dipping behind a motor boat when they became affected by the boat exhaust. One of the youths was overcome and submerged into the lake. Both incidents were initially attributed to incorrect causes--a car accident and a drowning--because of the false notion that carbon monoxide is not a hazard in a ventilated area. The carboxyhemoglobin levels in these victims were 78 and 62% respectively. It was only through laboratory testing that carbon monoxide poisoning was identified as the cause of their demise. Physicians as well as the public need to be aware of the potential for this life threatening hazard to occur so that there can be proper emergency treatment and the prevention of fatalities.

  16. Simultaneous Measurements of Eight Oxyanions Using High-Capacity Diffusive Gradients in Thin Films (Zr-Oxide DGT) with a High-Efficiency Elution Procedure.

    PubMed

    Ding, Shiming; Xu, Di; Wang, Yanping; Wang, Yan; Li, Yangyang; Gong, Mengdan; Zhang, Chaosheng

    2016-07-19

    A zirconium oxide binding gel-based diffusive gradients in thin films (Zr-oxide DGT) was developed for simultaneous measurements of P(V), As(V), Cr(VI), Mo(VI), Sb(V), Se(VI), V(V), and W(VI). All of the oxyanions were rapidly bound to Zr-oxide gel with differences in binding affinity. The eight bound oxyanions were successfully recovered by one-step elution using a mild reagent of 0.2 M NaOH-0.5 M H2O2 by overcoming the problems in analyses of the oxyanions. The optimized elution time was reduced to 3-5 h from 24-48 h required by other DGTs. DGT uptakes of all the oxyanions were independent of pH (4.42-8.45) and ionic strength (0.1-500 mM). The DGT capacities for six oxyanions detected in multioxyanion solution were only 0.19 to 0.35 times of those detected in single-oxyanion solution, reflecting a strong competition among the oxyanions during DGT uptake. Except for Se(VI) in seawater, Zr-oxide DGT accurately measured all of the oxyanions in synthetic freshwater and seawater, with the capacities ∼29 to >2397 times and ∼7.5 to 232 times those of two commonly used DGTs (Metsorb and precipitated ferrihydrite (PF) DGTs) in freshwater and seawater, respectively. Measurements by Zr-oxide DGT in contaminated sediments were in agreement with only two oxyanions with the two commonly used DGTs; the two DGTs accumulated less or no mass of other oxyanions. This study demonstrates significant advantage of Zr-oxide DGT over the other DGTs in simultaneous measurements of the eight oxyanions due to the former's high capacity and a wide tolerance to environmental interferences, together with a high efficiency in elution. PMID:27303914

  17. Diffusible gas transmitter signaling in the copepod crustacean Calanus finmarchicus: identification of the biosynthetic enzymes of nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) using a de novo assembled transcriptome

    PubMed Central

    Christie, Andrew E.; Fontanilla, Tiana M.; Roncalli, Vittoria; Cieslak, Matthew C.; Lenz, Petra H.

    2014-01-01

    Neurochemical signaling is a major component of physiological/behavioral control throughout the animal kingdom. Gas transmitters are perhaps the most ancient class of molecules used by nervous systems for chemical communication. Three gases are generally recognized as being produced by neurons: nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S). As part of an ongoing effort to identify and characterize the neurochemical signaling systems of the copepod Calanus finmarchicus, the biomass dominant zooplankton in much of the North Atlantic Ocean, we have mined a de novo assembled transcriptome for sequences encoding the neuronal biosynthetic enzymes of these gases, i.e. nitric oxide synthase (NOS), heme oxygenase (HO) and cystathionine β-synthase (CBS), respectively. Using Drosophila proteins as queries, two NOS-, one HO-, and one CBS-encoding transcripts were identified. Reverse BLAST and structural analyses of the deduced proteins suggest that each is a true member of its respective enzyme family. RNA-Seq data collected from embryos, early nauplii, late nauplii, early copepodites, late copepodites and adults revealed the expression of each transcript to be stage specific: one NOS restricted primarily to the embryo and the other was absent in the embryo but expressed in all other stages, no CBS expression in the embryo, but present in all other stages, and HO expressed across all developmental stages. Given the importance of gas transmitters in the regulatory control of a number of physiological processes, these data open opportunities for investigating the roles these proteins play under different life-stage and environmental conditions in this ecologically important species. PMID:24747481

  18. Carbon Monoxide from Biomass Burning

    NASA Technical Reports Server (NTRS)

    2002-01-01

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

  19. Carbon monoxide and lethal arrhythmias

    SciTech Connect

    Farber, J.P.; Schwartz, P.J.; Vanoli, E.; Stramba-Badiale, M.; De Ferrari, G.M. )

    1990-12-01

    The effect of acute exposure to carbon monoxide on ventricular arrhythmias was studied in a previously described chronically maintained animal model of sudden cardiac death. In 60 percent of dogs with a healed anterior myocardial infarction, the combination of mild exercise and acute myocardial ischemia induces ventricular fibrillation. The events in this model are highly reproducible, thus allowing study by internal control analysis. Dogs that develop ventricular fibrillation during the test of exercise and acute myocardial ischemia are considered at high risk for sudden death and are defined as 'susceptible'; dogs that survive the test without a fatal arrhythmia are considered at low risk for sudden death and are defined as 'resistant.' In the current study, the effects of carboxyhemoglobin levels ranging from 5 to 15 percent were tested in resistant and susceptible dogs. A trend toward higher heart rates was observed at all levels of carboxyhemoglobin, although significant differences were observed only with 15 percent carboxyhemoglobin. This trend was observed at rest and during exercise in both resistant and susceptible dogs. In resistant animals, in which acute myocardial ischemia is typically associated with bradycardia even under the control condition, this reflex response occurred earlier and was augmented after exposure to carbon monoxide. This effect may depend on the increased hypoxic challenge caused by carbon monoxide, and thus on an augmentation of the neural reflex activation or a sensitization of the sinus node to acetylcholine induced by hypoxia. In both resistant and susceptible dogs, carbon monoxide exposure induced a worsening of ventricular arrhythmias in a minority of cases. This worsening was not reproducible in subsequent trials. These data indicate that acute exposure to carbon monoxide is seldom arrhythmogenic in dogs that have survived myocardial infarction. (Abstract Truncated)

  20. A sulfur host based on titanium monoxide@carbon hollow spheres for advanced lithium–sulfur batteries

    PubMed Central

    Li, Zhen; Zhang, Jintao; Guan, Buyuan; Wang, Da; Liu, Li-Min; Lou, Xiong Wen (David)

    2016-01-01

    Lithium–sulfur batteries show advantages for next-generation electrical energy storage due to their high energy density and cost effectiveness. Enhancing the conductivity of the sulfur cathode and moderating the dissolution of lithium polysulfides are two key factors for the success of lithium–sulfur batteries. Here we report a sulfur host that overcomes both obstacles at once. With inherent metallic conductivity and strong adsorption capability for lithium-polysulfides, titanium monoxide@carbon hollow nanospheres can not only generate sufficient electrical contact to the insulating sulfur for high capacity, but also effectively confine lithium-polysulfides for prolonged cycle life. Additionally, the designed composite cathode further maximizes the lithium-polysulfide restriction capability by using the polar shells to prevent their outward diffusion, which avoids the need for chemically bonding all lithium-polysulfides on the surfaces of polar particles. PMID:27762261

  1. Estimating Effects of Brazilian Forest Wildfires on the Carbon Monoxide Concentration

    NASA Astrophysics Data System (ADS)

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

    2004-12-01

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

  2. Combining Natural Attenuation Capacity and use of Targeted Technological Mitigation Measures for Reducing Diffuse Nutrient Emissions to Surface Waters: The Danish Way

    NASA Astrophysics Data System (ADS)

    Kronvang, B.; Højberg, A. L.; Hoffmann, C. C.; Windolf, J.; Blicher-Mathiesen, G.

    2015-12-01

    Excess nitrogen (N) and phosphorus (P) emissions to surface waters are a high priority environmental problem worldwide for protection of water resources in times of population growth and climate change. As clean water is a scarce resource the struggle for reducing nutrient emissions are an ongoing issue for many countries and regions. Since the mid1980s a wide range of national regulatory general measures have been implemented to reduce land based nitrogen (N) and phosphorus (P) loadings of the Danish aquatic environment. These measures have addressed both point source emissions and emissions from diffuse sources especially from agricultural production. Following nearly 4 decades of combating nutrient pollution our surface waters such as lakes and estuaries are only slowly responding on the 50% reduction in N and 56% reduction in P. Therefore, the implementation of the EU Water Framework Directive in Danish surface waters still call for further reductions of N and P loadings. Therefore, a new era of targeted implemented measures was the outcome of a Commission on Nature and Agriculture established by the Danish Government in 2013. Their White Book points to the need of increased growth and better environment through more targeted and efficient regulation using advanced technological mitigation methods that are implemented intelligently according to the local natural attenuation capacity for nutrients in the landscape. As a follow up a national consensus model for N was established chaining existing leaching, 3D groundwater and surface water models that enable a calculation of the N dynamics and attenuation capacity within a scale of 15 km2. Moreover, several research projects have been conducted to investigate the effect of a suite of targeted mitigation measures such as restored natural wetlands, constructed wetlands, controlled drainage, buffer strips and constructed buffer strips. The results of these studies will be shared in this presentation.

  3. Contributors to diffusion impairment in HIV-infected persons.

    PubMed

    Gingo, Matthew R; He, Jiayan; Wittman, Catherine; Fuhrman, Carl; Leader, Joseph K; Kessinger, Cathy; Lucht, Lorrie; Slivka, William A; Zhang, Yingze; McMahon, Deborah K; Sciurba, Frank C; Morris, Alison

    2014-01-01

    Abnormal diffusing capacity is common in HIV-infected individuals, including never smokers. Aetiologies for diffusing capacity impairment in HIV are not understood, particularly in those without a history of cigarette smoking. Our study was a cross-sectional analysis of 158 HIV-infected individuals without acute respiratory symptoms or infection with the aim to determine associations between a diffusing capacity of the lung for carbon monoxide (D(LCO)) % predicted and participant demographics, pulmonary spirometric measures (forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity), radiographic emphysema (fraction of lung voxels < -950 Hounsfield units), pulmonary vascular/cardiovascular disease (echocardiographic tricuspid regurgitant jet velocity, N-terminal pro-brain natriuretic peptide) and airway inflammation (induced sputum cell counts), stratified by history of smoking. The mean D(LCO) was 65.9% predicted, and 55 (34.8%) participants had a significantly reduced D(LCO) (<60% predicted). Lower D(LCO) % predicted in ever-smokers was associated with lower post-bronchodilator FEV1 % predicted (p<0.001) and greater radiographic emphysema (p=0.001). In never-smokers, mean±SD D(LCO) was 72.7±13.4% predicted, and D(LCO) correlated with post-bronchodilator FEV1 (p=0.02), sputum neutrophils (p=0.03) and sputum lymphocytes (p=0.009), but not radiographic emphysema. Airway obstruction, emphysema and inflammation influence D(LCO) in HIV. Never-smokers may have a unique phenotype of diffusing capacity impairment. The interaction of multiple factors may account for the pervasive nature of diffusing capacity impairment in HIV infection.

  4. Carbon monoxide kinetics following simulated cigarette smoking

    SciTech Connect

    Karnik, A.S.; Coin, E.J.

    1980-05-01

    Carbon monoxide kinetics were measured in the blood (% carboxyhemoglobin) and alveolar phase (ppM carbon monoxide) after simulated cigarette smoking. Cigarette smoking was siumlated using the same amount of carbon monoxide that 2R1F cigarettes manufactured by the Tobacco Research Institute would contain. Ten boluses of air containing carbon monoxide equivalent to smoking one cigarette were inhaled by six healthy nonsmoker volunteers. Carbon monoxide in the air phase was measured by an Ecolyzer and carboxyhemoglobin was measured by a CO-Oximeter. The mean rise in alveolar carbon monoxide immediately and 20 min after inhaling the last bolus was 3.3 and 3.1 ppM, respectively (p<.005). The mean rise in carboxyhemoglobin immediately and 20 min after inhalation of the last bolus was 0.8 and 0.5% respectively (P<.005). The changes in carboxyhemoglobin were found to be similar to changes that occur when one cigarette is actually smoked.

  5. 21 CFR 862.3220 - Carbon monoxide test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon monoxide test system. 862.3220 Section 862....3220 Carbon monoxide test system. (a) Identification. A carbon monoxide test system is a device intended to measure carbon monoxide or carboxyhemoglobin (carbon monoxide bound to the hemoglobin in...

  6. 21 CFR 862.3220 - Carbon monoxide test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon monoxide test system. 862.3220 Section 862....3220 Carbon monoxide test system. (a) Identification. A carbon monoxide test system is a device intended to measure carbon monoxide or carboxyhemoglobin (carbon monoxide bound to the hemoglobin in...

  7. 21 CFR 862.3220 - Carbon monoxide test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon monoxide test system. 862.3220 Section 862....3220 Carbon monoxide test system. (a) Identification. A carbon monoxide test system is a device intended to measure carbon monoxide or carboxyhemoglobin (carbon monoxide bound to the hemoglobin in...

  8. 21 CFR 862.3220 - Carbon monoxide test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon monoxide test system. 862.3220 Section 862....3220 Carbon monoxide test system. (a) Identification. A carbon monoxide test system is a device intended to measure carbon monoxide or carboxyhemoglobin (carbon monoxide bound to the hemoglobin in...

  9. 21 CFR 862.3220 - Carbon monoxide test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon monoxide test system. 862.3220 Section 862....3220 Carbon monoxide test system. (a) Identification. A carbon monoxide test system is a device intended to measure carbon monoxide or carboxyhemoglobin (carbon monoxide bound to the hemoglobin in...

  10. Coupling of Carbon Monoxide with Nitrogen Monoxide at a Frustrated Lewis Pair Template.

    PubMed

    Ye, Ke-Yin; Kehr, Gerald; Daniliuc, Constantin G; Liu, Lei; Grimme, Stefan; Erker, Gerhard

    2016-08-01

    Coupling of carbon monoxide with nitrogen monoxide was achieved at a frustrated Lewis pair template. This unique reaction uses hydride as an auxiliary, which reductively activates carbon monoxide at the frustrated Lewis pair. The CO/NO coupling reaction then takes place through a pathway involving a radical reaction in which the hydrogen atom auxiliary is eventually removed again.

  11. On the origin of the heat capacity feature of annealed ices and ice clathrates, and interpreting water's diffusivity in terms of the entropy

    NASA Astrophysics Data System (ADS)

    Johari, G. P.

    2000-08-01

    In order to investigate the origins of (i) the spontaneous temperature rise on annealing pure hexagonal and cubic ices and ice clathrates and (ii) the sigmoid-shape increase in the heat capacity, C p, on heating the annealed samples, the enthalpy and entropy decrease on annealing of pure cubic ice and one ice clathrate have been determined from their C p data. This decrease is found to be much higher than that expected from orientational relaxation of H 2O molecules and that calculated from the spontaneous decrease in the Bjerrum or orientational defects concentrations. On this basis and the known observation that dopants not only decrease the relaxation time of the ices and ice clathrates but also modify the shape of the C p-increase feature, it is concluded that the spontaneous temperature rise on annealing occurs when some of the H 2O molecules achieve a preferential orientation, which is equivalent to their partial proton ordering. The sigmoid-shape C p-feature observed on heating the annealed samples is therefore due to the time- and temperature-dependent recovery of their random orientations or complete proton disorder. This is fundamentally different from structural relaxation in glasses whose entropy of disorder itself increases on heating. In a second aspect of the study, the known temperature dependence of the self-diffusion coefficient of water is used to calculate two fundamental quantities of the configurational entropy theory: (i) the size of the cooperatively rearranging regions, which is 4.7 molecules at 150 K, and (ii) the temperature-invariant energy, which is 7.4 kJ mol -1. These seem plausible and similar to those observed for other liquids. Finally, it is pointed out that a comparison of bulk water's dielectric properties with those of the ions afflicted, two-molecule thick water layer between the platelets of sodium vermiculite clay [R. Bergman, J. Sweson, Nature 403 (2000) 283], is inappropriate on fundamental grounds.

  12. A case-study of water transport in co-occurring ring- versus diffuse-porous trees: contrasts in water-status, conducting capacity, cavitation and vessel refilling.

    PubMed

    Taneda, Haruhiko; Sperry, John S

    2008-11-01

    Recent work has suggested that the large earlywood vessels of ring-porous trees can be extraordinarily vulnerable to cavitation making it necessary that these trees maintain a consistent and favorable water status. We compared cavitation resistance, vessel refilling, transport capacity and water status in a study of ring-porous Quercus gambelii Nutt. (oak) and diffuse-porous Acer grandidentatum Nutt. (maple). These species co-dominate summer-dry foothills in the western Rocky Mountains of the USA. Native embolism measurements, dye perfusions and balance pressure exudation patterns indicated that the large earlywood vessels of 2-3-year-old oak stems cavitated extensively on a daily basis as predicted from laboratory vulnerability curves, resulting in a more than 80% reduction in hydraulic conductivity. Maple branches showed virtually no cavitation. Oak vessels refilled on a daily basis, despite negative xylem pressure in the transpiration stream, indicating active pressurization of embolized vessels. Conductivity and whole-tree water use in oak were between about one-half and two-thirds that in maple on a stem-area basis; but were similar or greater on a leaf-area basis. Oak maintained steady and modest negative xylem pressure potentials during the growing season despite little rainfall, indicating isohydric water status and reliance on deep soil water. Maple was markedly anisohydric and developed more negative pressure potentials during drought, suggesting use of shallower soil water. Although ring porosity may have evolved as a mechanism for coping with winter freezing, this study suggests that it also has major consequences for xylem function during the growing season. PMID:18765369

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

    SciTech Connect

    Jones, R.D. )

    1990-01-09

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

  14. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... using gas detector tube units certified by NIOSH under 30 CFR part 11 or other measuring instruments... 29 Labor 7 2014-07-01 2014-07-01 false Carbon monoxide. 1917.24 Section 1917.24 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.24 Carbon monoxide. (a) Exposure limits. The...

  15. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... using gas detector tube units certified by NIOSH under 30 CFR part 11 or other measuring instruments... 29 Labor 7 2012-07-01 2012-07-01 false Carbon monoxide. 1917.24 Section 1917.24 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.24 Carbon monoxide. (a) Exposure limits. The...

  16. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... using gas detector tube units certified by NIOSH under 30 CFR part 11 or other measuring instruments... 29 Labor 7 2010-07-01 2010-07-01 false Carbon monoxide. 1917.24 Section 1917.24 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.24 Carbon monoxide. (a) Exposure limits. The...

  17. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... using gas detector tube units certified by NIOSH under 30 CFR part 11 or other measuring instruments... 29 Labor 7 2011-07-01 2011-07-01 false Carbon monoxide. 1917.24 Section 1917.24 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.24 Carbon monoxide. (a) Exposure limits. The...

  18. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... using gas detector tube units certified by NIOSH under 30 CFR part 11 or other measuring instruments... 29 Labor 7 2013-07-01 2013-07-01 false Carbon monoxide. 1917.24 Section 1917.24 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.24 Carbon monoxide. (a) Exposure limits. The...

  19. Method of removing carbon monoxide from gases

    DOEpatents

    Gerstein, Bernard C.; Macaulay, David B.

    1976-06-01

    A process and catalyst are disclosed for purifying an atmosphere containing carbon monoxide by passing the atmosphere through a bed of a catalyst of TbO.sub.x, where x = 1.8 to 1.5, which oxidizes the carbon monoxide to carbon dioxide.

  20. Electronic Transitions of Yttrium Monoxide

    NASA Astrophysics Data System (ADS)

    Ng, Y. W.; Wang, Na; Clark, Andrew B.; Cheung, A. S.-C.

    2013-06-01

    The electronic transition spectrum of yttrium monoxide (YO) in the spectral region between 284nm and 307nm has been recorded using laser ablation/reaction free-jet expansion and laser induced fluorescence (LIF) spectroscopy. The YO molecule was produced by reacting laser-ablated yttrium atoms with O_{2} seeded in argon. Twenty transition bands were observed in that region and a few bands were selected for further study using optical-optical double resonance (OODR) spectroscopy. The excited C^{2} Π state has been reached via the intermediate B^{2} Σ^{+} state from the ground X^{2} Σ^{+} state. The excited sub-states observed so far have Ω = 0.5 and 1.5. A least squares fit of the measured rotational lines yielded molecular constants for the newly observed excited states.

  1. Carbon monoxide and the burning earth

    SciTech Connect

    Newell, R.E.; Reichle, H.G. Jr.; Seiler, W.

    1989-10-01

    Carbon monoxide is one of many gases whose presence in the atmosphere is blamed largely on industrial activity in the Northern Hemisphere. Data collected by the authors show that the gas is also abundant in the Southern Hemisphere, where it comes mainly from the burning of tropical rain forests and savannas. The high levels of carbon monoxide confirm other evidence that the rain forests are being diminished rapidly, which may affect the climates of these regions as well as globally. Increases in carbon monoxide could also encourage the accumulation of pollutant gases such as ozone and methane. The first is highly toxic to plants and the second would add to the greenhouse effect.

  2. Tests confirm gas heat as monoxide source

    SciTech Connect

    Besch, E.

    1984-03-01

    Six tests were conducted to demonstrate the potential for natural gas or oil-fired forced warm air heating equipment to produce carbon monoxide emission when the combustion process is impeded by typical causes found in households. In the case of the gas-fired units, impeded combustion produced a smell of aldehyde and various levels of carbon monoxide emission; all within the level dangerous to health. It was concluded that oil-fired warm air systems do not pose a carbon monoxide danger but that natural gas warm air systems do pose a real danger and should be so identified.

  3. Effects of carbon monoxide on isolated heart muscle cells. Research report, March 1989-February 1992

    SciTech Connect

    Wittenberg, B.A.; Wittenberg, J.B.

    1993-01-01

    By sequestering intracellular myoglobin of cardiac muscle cells in the nonfunctioning carboxymyoglobin form, carbon monoxide blocks myoglobin-facilitated diffusion of oxygen, as well as myoglobin-mediated oxidative phosphorylation. The authors explored the hypothesis that the carbon monoxide blockade of myoglobin function may be responsible at the cellular level for a component of the cardiotoxicity of carbon monoxide observed during exercise. At physiological oxygen pressures no greater than 5 torr, after sequestration of approximately 50% of the myoglobin, steady-state oxygen uptake decreased significantly less than the respiration of cell groups for which the fraction of carboxymyoglobin was 0% to 40%. When respiration is diminished, the rate of oxidative phosphorylation also decreases. Thus, they concluded that sequestering intracellular myoglobin as carboxymyoglobin significantly decreased the rate of oxidative phosphorylation of isolated cardiac myocytes. They estimate that intracellular myoglobin-dependent oxidative phosphorylation will be inhibited when approximately 20% to 40% of the arterial hemoglobin in the whole animal is carboxyhemoglobin.

  4. 40 CFR 52.1237 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) The base year carbon monoxide emission inventory requirement of section 187... Metropolitan Area and Minneapolis-St. Paul Metropolitan Area. (b) Approval—The 1993 carbon monoxide...

  5. 40 CFR 52.2353 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. Determination. EPA has determined that the Provo carbon monoxide “moderate” nonattainment area attained the carbon monoxide national ambient air quality standard by December 31, 1995....

  6. 40 CFR 52.1237 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) The base year carbon monoxide emission inventory requirement of section 187... Metropolitan Area and Minneapolis-St. Paul Metropolitan Area. (b) Approval—The 1993 carbon monoxide...

  7. 40 CFR 52.2353 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. Determination. EPA has determined that the Provo carbon monoxide “moderate” nonattainment area attained the carbon monoxide national ambient air quality standard by December 31, 1995....

  8. 40 CFR 52.1682 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Approval—The November 13, 1992 revision to the carbon monoxide state implementation... attainment of the National Ambient Air Quality Standard for carbon monoxide through the year 2003....

  9. 40 CFR 52.2353 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. Determination. EPA has determined that the Provo carbon monoxide “moderate” nonattainment area attained the carbon monoxide national ambient air quality standard by December 31, 1995....

  10. 40 CFR 52.2353 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. Determination. EPA has determined that the Provo carbon monoxide “moderate” nonattainment area attained the carbon monoxide national ambient air quality standard by December 31, 1995....

  11. 40 CFR 91.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration... Provisions § 91.317 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR carbon monoxide analyzer... service and annually thereafter, check the NDIR carbon monoxide analyzer for response to water vapor...

  12. 40 CFR 52.1237 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) The base year carbon monoxide emission inventory requirement of section 187... Metropolitan Area and Minneapolis-St. Paul Metropolitan Area. (b) Approval—The 1993 carbon monoxide...

  13. 40 CFR 52.1682 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Approval—The November 13, 1992 revision to the carbon monoxide state implementation... attainment of the National Ambient Air Quality Standard for carbon monoxide through the year 2003....

  14. 40 CFR 52.2353 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. Determination. EPA has determined that the Provo carbon monoxide “moderate” nonattainment area attained the carbon monoxide national ambient air quality standard by December 31, 1995....

  15. 40 CFR 52.1682 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Approval—The November 13, 1992 revision to the carbon monoxide state implementation... attainment of the National Ambient Air Quality Standard for carbon monoxide through the year 2003....

  16. 40 CFR 52.1682 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Approval—The November 13, 1992 revision to the carbon monoxide state implementation... attainment of the National Ambient Air Quality Standard for carbon monoxide through the year 2003....

  17. 40 CFR 52.1682 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Approval—The November 13, 1992 revision to the carbon monoxide state implementation... attainment of the National Ambient Air Quality Standard for carbon monoxide through the year 2003....

  18. 40 CFR 52.1237 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) The base year carbon monoxide emission inventory requirement of section 187... Metropolitan Area and Minneapolis-St. Paul Metropolitan Area. (b) Approval—The 1993 carbon monoxide...

  19. 40 CFR 52.1237 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) The base year carbon monoxide emission inventory requirement of section 187... Metropolitan Area and Minneapolis-St. Paul Metropolitan Area. (b) Approval—The 1993 carbon monoxide...

  20. Room-temperature carbon monoxide oxidation by oxygen over Pt/Al2O3 mediated by reactive platinum carbonates

    PubMed Central

    Newton, Mark A.; Ferri, Davide; Smolentsev, Grigory; Marchionni, Valentina; Nachtegaal, Maarten

    2015-01-01

    Room-temperature carbon monoxide oxidation, important for maintaining clean air among other applications, is challenging even after a century of research into carbon monoxide oxidation. Here we report using time-resolved diffuse reflectance infrared spectroscopy, X-ray absorption fine structure spectroscopy and mass spectrometry a platinum carbonate-mediated mechanism for the room-temperature oxidation of carbon monoxide. By applying a periodic reduction–oxidation mode of operation we further show that this behaviour is reversible and can be formed into a catalytic cycle that requires molecular communication between metallic platinum nanoparticles and highly dispersed oxidic platinum centres. A new possibility for the attainment of low-temperature oxidation of carbon monoxide is therefore demonstrated. PMID:26489669

  1. Room-temperature carbon monoxide oxidation by oxygen over Pt/Al2O3 mediated by reactive platinum carbonates.

    PubMed

    Newton, Mark A; Ferri, Davide; Smolentsev, Grigory; Marchionni, Valentina; Nachtegaal, Maarten

    2015-01-01

    Room-temperature carbon monoxide oxidation, important for maintaining clean air among other applications, is challenging even after a century of research into carbon monoxide oxidation. Here we report using time-resolved diffuse reflectance infrared spectroscopy, X-ray absorption fine structure spectroscopy and mass spectrometry a platinum carbonate-mediated mechanism for the room-temperature oxidation of carbon monoxide. By applying a periodic reduction-oxidation mode of operation we further show that this behaviour is reversible and can be formed into a catalytic cycle that requires molecular communication between metallic platinum nanoparticles and highly dispersed oxidic platinum centres. A new possibility for the attainment of low-temperature oxidation of carbon monoxide is therefore demonstrated.

  2. Polymer-Based Carbon Monoxide Sensors

    NASA Technical Reports Server (NTRS)

    Homer, M. L.; Shevade, A. V.; Zhou, H.; Kisor, A. K.; Lara, L. M.; Yen, S.-P. S.; Ryan, M. A.

    2010-01-01

    Polymer-based sensors have been used primarily to detect volatile organics and inorganics; they are not usually used for smaller, gas phase molecules. We report the development and use of two types of polymer-based sensors for the detection of carbon monoxide. Further understanding of the experimental results is also obtained by performing molecular modeling studies to investigate the polymer-carbon monoxide interactions. The first type is a carbon-black-polymer composite that is comprised of a non-conducting polymer base that has been impregnated with carbon black to make it conducting. These chemiresistor sensors show good response to carbon monoxide but do not have a long lifetime. The second type of sensor has a non-conducting polymer base but includes both a porphyrin-functionalized polypyrrole and carbon black. These sensors show good, repeatable and reversible response to carbon monoxide at room temperature.

  3. Protecting Children from Carbon Monoxide Poisoning

    MedlinePlus

    ... monoxide poisoning increases after disasters when gasoline- or diesel-powered generators may be more frequently used to ... can mimic symptoms of sea sickness. Schedule regular engine and exhaust system maintenance. Consider installing a carbon ...

  4. Carbon-monoxide Indicators for Aircraft

    NASA Technical Reports Server (NTRS)

    Womack, S H J; Peterson, J B

    1936-01-01

    Several improvements that have been made on commercially available carbon-monoxide indicators to make them more suitable for aircraft use are described. These improvements include an automatic flow regulator, which permits the use of a simplified instrument on aircraft where a source of suction is available, and a more reliable alarm attachment. A field method for testing instruments on standard samples of carbon monoxide is described. Performance data and instructions in operation and maintenance are given.

  5. An unusual case of carbon monoxide poisoning.

    PubMed Central

    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

  6. Device for staged carbon monoxide oxidation

    DOEpatents

    Vanderborgh, Nicholas E.; Nguyen, Trung V.; Guante, Jr., Joseph

    1993-01-01

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

  7. Therapeutic Applications of Carbon Monoxide

    PubMed Central

    Knauert, Melissa; Vangala, Sandeep; Haslip, Maria; Lee, Patty J.

    2013-01-01

    Heme oxygenase-1 (HO-1) is a regulated enzyme induced in multiple stress states. Carbon monoxide (CO) is a product of HO catalysis of heme. In many circumstances, CO appears to functionally replace HO-1, and CO is known to have endogenous anti-inflammatory, anti-apoptotic, and antiproliferative effects. CO is well studied in anoxia-reoxygenation and ischemia-reperfusion models and has advanced to phase II trials for treatment of several clinical entities. In alternative injury models, laboratories have used sepsis, acute lung injury, and systemic inflammatory challenges to assess the ability of CO to rescue cells, organs, and organisms. Hopefully, the research supporting the protective effects of CO in animal models will translate into therapeutic benefits for patients. Preclinical studies of CO are now moving towards more complex damage models that reflect polymicrobial sepsis or two-step injuries, such as sepsis complicated by acute respiratory distress syndrome. Furthermore, co-treatment and post-treatment with CO are being explored in which the insult occurs before there is an opportunity to intervene therapeutically. The aim of this review is to discuss the potential therapeutic implications of CO with a focus on lung injury and sepsis-related models. PMID:24648866

  8. Electronic Transitions of Ruthenium Monoxide

    NASA Astrophysics Data System (ADS)

    Wang, Na; Ng, Y. W.; Cheung, A. S.-C.

    2013-06-01

    The electronic transition spectrum of ruthenium monoxide (RuO) molecule in the spectral region between 545nm to 640nm has been recorded and analyzed using laser ablation/reaction free-jet expansion and laser induced fluorescence spectroscopy. The RuO molecule was produced by reacting laser- ablated ruthenium atoms with N_{2}O seeded in argon. Nine vibrational bands were recorded and they are identified to be belonging to four electronic transition systems, namely the [18.1]Ω = 4 - X^{5} Δ_4 transition, [16.0]^{5} Φ_5 - X^{5} Δ_4 transition, [18.1]Ω = 3 - X^{5} Δ_3, and [15.8] ^{5} Φ_4 - X^{5} Δ_3 transition. RuO has been determined to have a X^{5} Δ_4 ground state. A least squares fit of the measured rotational lines yielded molecular constants for the ground and the low-lying electronic states. A molecular orbital energy level diagram has been used to help with the assignment of the observed electronic states.

  9. Management of carbon monoxide poisoning.

    PubMed

    Ilano, A L; Raffin, T A

    1990-01-01

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

  10. Observing iodine monoxide from satellite

    NASA Astrophysics Data System (ADS)

    Schoenhardt, Anja; Richter, Andreas; Begoin, Mathias; Wittrock, Folkard; Burrows, John P.

    Iodine and iodine monoxide (IO) belong to the group of reactive halogen species, and they may impact on atmospheric chemical composition and the radiation budget. Vice versa, sur-rounding conditions may influence the emissions and pathways of iodine compounds. Although atmospheric amounts of iodine are typically fairly small, the impact may still be substantial. Iodine radicals are photolytically released from precursors and may then cause catalytic ozone depletion. In this reaction with ozone, IO is produced, a molecule which plays a central role in the iodine cycling. Via self reactions of IO, higher iodine oxides form and initiate the formation of new particles, which may change the atmospheric radiation balance. Apart from that, many living species, including human beings, vertebrates in general, but also micro-and macroalgae species, e.g., depend on the supply with iodine. Consequently, it is necessary to understand the cycling of iodine through the different components of the Earth system. Although increas-ing research effort in the form of field, laboratory and modeling studies has strongly improved our knowledge and understanding of iodine abundances and impact, still many open questions remain. The relevance of iodine on a global scale is not well known yet; sources are not well quantified and release processes are not fully understood. Since recently, IO may be observed from space by the SCIAMACHY instrument on the EN-VISAT satellite, which is in a near-polar, sun-synchronous orbit. Nadir observations from SCIAMACHY have been analysed for the IO absorption signature in the visible wavelength range for several mission years. IO amounts are typically close to the limit of detectability of SCIAMACHY. Detecting such small quantities, careful attention needs to be paid to system-atic errors, spectral correlations and resulting retrieval artefacts. Subsequently, appropriate temporal averaging is utilised to improve the signal-to-noise ratio. The resulting

  11. Catalytic hydrogenation of carbon monoxide

    SciTech Connect

    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.

  12. [Carbon monoxide contamination: an environmental health problem].

    PubMed

    Téllez, Jairo; Rodríguez, Alba; Fajardo, Alvaro

    2006-01-01

    Carbon monoxide is considered to be a major factor contaminating earth's atmosphere. The main sources producing this contamination are cars using gasoline or diesel fuel and industrial processes using carbon compounds; these two are responsible for 80% of carbon monoxide being emitted to the atmosphere. This substance has a well-known toxic effect on human beings and its acute poisonous effects (including death) have been widely studied; however, its long-term chronic effects are still not known. During the last few years, experimental research on animals and studies of human epidemiology have established the relationship between chronic exposure to low and middle levels of carbon monoxide in breathable air and adverse effects on human health, especially on organs consuming large amounts of oxygen such as the heart and brain. Harmful cardiovascular and neuropsychological effects have been documented in carbon monoxide concentration in air of less than 25 ppm and in carboxyhaemoglobin levels in blood of less than 10%. The main cardiac damage described to date has been high blood pressure, cardiac arrhythm and electrocardiograph signs of ischemia. Lack of memory, attention, concentration and Parkinson-type altered movement are the neuropsychological changes most frequently associated with chronic exposure to low levels of carbon monoxide and carboxyhaemoglobin. PMID:16703967

  13. Carbon monoxide sensor and method of use

    DOEpatents

    Dutta, Prabir K.; Swartz, Scott L.; Holt, Christopher T.; Revur, Ramachandra Rao

    2006-01-10

    A sensor and method of use for detection of low levels of carbon monoxide in gas mixtures. The approach is based on the change in an electrical property (for example: resistance) that occurs when carbon monoxide is selectively absorbed by a film of copper chloride (or other metal halides). The electrical property change occurs rapidly with both increasing and decreasing CO contents, varies with the amount of CO from the gas stream, and is insensitive to the presence of hydrogen. To make a sensor using this approach, the metal halide film will deposited onto an alumina substrate with electrodes. The sensor may be maintained at the optimum temperature with a thick film platinum heater deposited onto the opposite face of the substrate. When the sensor is operating at an appropriate (and constant) temperature, the magnitude of the electrical property measured between the interdigital electrodes will provide a measure of the carbon monoxide content of the gas.

  14. CPSC Warns of Carbon Monoxide Poisoning with Camping Equipment

    MedlinePlus

    ... Warns of Carbon Monoxide Poisoning Hazard with Camping Equipment The U.S. Consumer Product Safety Commission (CPSC) warns ... about the carbon monoxide (CO) hazard with camping equipment. CO can kill you! From 2002–2006, CPSC ...

  15. [Carbon monoxide metabolism by photosynthetic bacteria]. Progress report

    SciTech Connect

    Not Available

    1989-12-31

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

  16. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Carbon monoxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.522-78 Carbon monoxide analyzer... thereafter the NDIR carbon monoxide analyzer shall be checked for response to water vapor and CO2: (1)...

  17. 40 CFR 52.1132 - Control strategy: Carbon Monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon Monoxide. 52... strategy: Carbon Monoxide. (a) Approval—On November 13, 1992, the Massachusetts Department of Environmental Protection submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base...

  18. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.522-78 Carbon monoxide analyzer... thereafter the NDIR carbon monoxide analyzer shall be checked for response to water vapor and CO2: (1)...

  19. 40 CFR 86.122-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon monoxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.122-78 Carbon monoxide analyzer calibration. The NDIR carbon monoxide analyzer shall receive the following initial and periodic calibrations: (a) Initial...

  20. 40 CFR 52.1528 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) Approval—On February 1, 1999, the New Hampshire Department of Environmental... program for carbon monoxide that ceased operating on January 1, 1995. The Nashua...

  1. 40 CFR 52.1373 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) On July 8, 1997, the Governor of Montana submitted revisions to the SIP narrative for the Missoula carbon monoxide control plan. (b) Revisions to the Montana State Implementation...

  2. 40 CFR 52.1373 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) On July 8, 1997, the Governor of Montana submitted revisions to the SIP narrative for the Missoula carbon monoxide control plan. (b) Revisions to the Montana State Implementation...

  3. 40 CFR 52.1887 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Part D—Approval—The following portions of the Ohio plan are approved: (1) The carbon...) The carbon monoxide attainment and reasonable further progress demonstrations for the following...

  4. 40 CFR 52.1887 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Part D—Approval—The following portions of the Ohio plan are approved: (1) The carbon...) The carbon monoxide attainment and reasonable further progress demonstrations for the following...

  5. 40 CFR 60.103 - Standard for carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for carbon monoxide. 60.103... Refineries § 60.103 Standard for carbon monoxide. Each owner or operator of any fluid catalytic cracking unit... regenerator any gases that contain carbon monoxide (CO) in excess of 500 ppm by volume (dry basis)....

  6. 40 CFR 52.1528 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) Approval—On February 1, 1999, the New Hampshire Department of Environmental... program for carbon monoxide that ceased operating on January 1, 1995. The Nashua...

  7. 40 CFR 52.1528 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) Approval—On February 1, 1999, the New Hampshire Department of Environmental... program for carbon monoxide that ceased operating on January 1, 1995. The Nashua...

  8. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.522-78 Carbon monoxide analyzer... thereafter the NDIR carbon monoxide analyzer shall be checked for response to water vapor and CO2: (1)...

  9. 40 CFR 52.1132 - Control strategy: Carbon Monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon Monoxide. 52... strategy: Carbon Monoxide. (a) Approval—On November 13, 1992, the Massachusetts Department of Environmental Protection submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base...

  10. 40 CFR 52.1528 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) Approval—On February 1, 1999, the New Hampshire Department of Environmental... program for carbon monoxide that ceased operating on January 1, 1995. The Nashua...

  11. 40 CFR 52.1887 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Part D—Approval—The following portions of the Ohio plan are approved: (1) The carbon...) The carbon monoxide attainment and reasonable further progress demonstrations for the following...

  12. 40 CFR 52.1132 - Control strategy: Carbon Monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon Monoxide. 52... strategy: Carbon Monoxide. (a) Approval—On November 13, 1992, the Massachusetts Department of Environmental Protection submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base...

  13. 40 CFR 86.122-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Carbon monoxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.122-78 Carbon monoxide analyzer calibration. The NDIR carbon monoxide analyzer shall receive the following initial and periodic calibrations: (a) Initial...

  14. 40 CFR 52.1373 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) On July 8, 1997, the Governor of Montana submitted revisions to the SIP narrative for the Missoula carbon monoxide control plan. (b) Revisions to the Montana State Implementation...

  15. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon monoxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.522-78 Carbon monoxide analyzer... thereafter the NDIR carbon monoxide analyzer shall be checked for response to water vapor and CO2: (1)...

  16. 40 CFR 52.1132 - Control strategy: Carbon Monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon Monoxide. 52... strategy: Carbon Monoxide. (a) Approval—On November 13, 1992, the Massachusetts Department of Environmental Protection submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base...

  17. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Carbon monoxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.522-78 Carbon monoxide analyzer... thereafter the NDIR carbon monoxide analyzer shall be checked for response to water vapor and CO2: (1)...

  18. 40 CFR 60.103 - Standard for carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for carbon monoxide. 60.103... Refineries § 60.103 Standard for carbon monoxide. Each owner or operator of any fluid catalytic cracking unit... regenerator any gases that contain carbon monoxide (CO) in excess of 500 ppm by volume (dry basis)....

  19. 40 CFR 60.103 - Standard for carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for carbon monoxide. 60.103... Refineries § 60.103 Standard for carbon monoxide. Each owner or operator of any fluid catalytic cracking unit... regenerator any gases that contain carbon monoxide (CO) in excess of 500 ppm by volume (dry basis)....

  20. 40 CFR 52.1373 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) On July 8, 1997, the Governor of Montana submitted revisions to the SIP narrative for the Missoula carbon monoxide control plan. (b) Revisions to the Montana State Implementation...

  1. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration... Emission Test Equipment Provisions § 90.317 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR carbon monoxide analyzer as described in this section. (b) Initial and periodic interference. Prior...

  2. 40 CFR 52.1528 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... strategy: Carbon monoxide. (a) Approval—On February 1, 1999, the New Hampshire Department of Environmental... program for carbon monoxide that ceased operating on January 1, 1995. The Nashua...

  3. 40 CFR 52.1373 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) On July 8, 1997, the Governor of Montana submitted revisions to the SIP narrative for the Missoula carbon monoxide control plan. (b) Revisions to the Montana State Implementation...

  4. 40 CFR 52.1887 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52...: Carbon monoxide. (a) Part D—Approval—The following portions of the Ohio plan are approved: (1) The carbon...) The carbon monoxide attainment and reasonable further progress demonstrations for the following...

  5. 40 CFR 52.1132 - Control strategy: Carbon Monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon Monoxide. 52... strategy: Carbon Monoxide. (a) Approval—On November 13, 1992, the Massachusetts Department of Environmental Protection submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base...

  6. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  7. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  8. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  9. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  10. 40 CFR 52.376 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... monitoring network in each carbon monoxide maintenance area; implement contingency measures in the event of... three maintenance areas; coordinate with EPA in the event the carbon monoxide design value(s) in any... maintenance plan 8-hour carbon monoxide design value criterion of 7.65 parts per million. If the...

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

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

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

    NASA Technical Reports Server (NTRS)

    Zhao, Y.; Shadman, F.

    1991-01-01

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

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

    PubMed

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

    2013-01-01

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

  14. Carbon monoxide poisoning associated with narghile use.

    PubMed

    Cavus, Umut Yucel; Rehber, Zehra Hamiyet; Ozeke, Ozcan; Ilkay, Erdogan

    2010-05-01

    The case history is presented of a healthy 25-year-old man who was admitted to hospital after two syncopal episodes caused by carbon monoxide poisoning after smoking narghile. Clinicians should be aware of this association when they evaluate syncope in the emergency department, especially in narghile users. PMID:20442182

  15. Selective Oxidizer For Removal Of Carbon Monoxide

    NASA Technical Reports Server (NTRS)

    Trocciola, John C.; Schroll, Craig R.; Lesieur, Roger R.

    1996-01-01

    Catalytic apparatus selectively oxidizes most of carbon monoxide (without oxidizing hydrogen) in stream of reformed fuel gas fed to low-temperature fuel cell. Multiple catalytic stages at progressively lower temperatures operate without becoming poisoned. Catalysts used to oxidize CO selectively include platinum on alumina and commercial catalyst known as "Selectoxo."

  16. Carbon Monoxide, A Bibliography With Abstracts.

    ERIC Educational Resources Information Center

    Cooper, Anna Grossman

    Included is a review of the carbon monoxide related literature published from 1880 to 1966. The 983 references with abstracts are grouped into these broad categories: Analysis, Biological Effects, Blood Chemistry, Control, Criteria and Standards, Instruments and Techniques, Sampling and Network Operations, and Sources. The Biological Effects group…

  17. Carbon Monoxide Poisoning in an Elementary School

    ERIC Educational Resources Information Center

    Comfort, Robert J.; Daveler, Jay

    1977-01-01

    Described is an investigation conducted by municipal inspection and code enforcement personnel following an episode of carbon monoxide poisoning among elementary school children in a small eastern Pennsylvania community in 1975. The need for a reevaluation of existing building code standards is emphasized. (BT)

  18. Method and apparatus for selective removal of carbon monoxide

    DOEpatents

    Borup, Rodney L.; Skala, Glenn W.; Brundage, Mark A.; LaBarge, William J.

    2000-01-01

    There is provided a method and apparatus for treatment of a hydrogen-rich gas to reduce the carbon monoxide content thereof by reacting the carbon monoxide in the gas with an amount of oxygen sufficient to oxidize at least a portion of the carbon monoxide in the presence of a catalyst in a desired temperature range without substantial reaction of hydrogen. The catalyst is an iridium-based catalyst dispersed on, and supported on, a carrier. In the presence of the catalyst, carbon monoxide in a hydrogen-rich feed gas is selectively oxidized such that a product stream is produced with a very low carbon monoxide content.

  19. An indicator to map diffuse chemical river pollution considering buffer capacity of riparian vegetation--a pan-European case study on pesticides.

    PubMed

    Weissteiner, Christof J; Pistocchi, Alberto; Marinov, Dimitar; Bouraoui, Fayçal; Sala, Serenella

    2014-06-15

    Vegetated riparian areas alongside streams are thought to be effective at intercepting and controlling chemical loads from diffuse agricultural sources entering water bodies. Based on a recently compiled European map of riparian zones and a simplified soil chemical balance model, we propose a new indicator at a continental scale. QuBES (Qualitative indicator of Buffered Emissions to Streams) allows a qualitative assessment of European rivers exposed to pesticide input. The indicator consists of normalised pesticide loads to streams computed through a simplified steady-state fate model that distinguishes various chemical groups according to physico-chemical behaviour (solubility and persistence). The retention of pollutants in the buffer zone is modelled according to buffer width and sorption properties. While the indicator may be applied for the study of a generic emission pattern and for a chemical of generic properties, we demonstrate it to the case of agricultural emissions of pesticides. Due to missing geo-spatial data of pesticide emissions, a total pesticide emission scenario is assumed. The QuBES indicator is easy to calculate and requires far less input data and parameterisation than typical chemical-specific models. At the same time, it allows mapping of (i) riparian buffer permeability, (ii) chemical runoff from soils, and (iii) the buffered load of chemicals to the stream network. When the purpose of modelling is limited to identifying chemical pollution patterns and understanding the relative importance of emissions and natural attenuation in soils and stream buffer strips, the indicator may be suggested as a screening level, cost-effective alternative to spatially distributed models of higher complexity.

  20. Enhanced carbon monoxide utilization in methanation process

    DOEpatents

    Elek, Louis F.; Frost, Albert C.

    1984-01-01

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

  1. Particulate, carbon monoxide, and acid emission factors for residential wood burn stoves

    SciTech Connect

    Burnet, P.G.; Edmisten, N.G.; Tiegs, P.E.; Houck, J.E.; Yoder, R.A.

    1986-09-01

    Emissions from residential wood burning stoves are of increasing concern in many areas. This concern is due to the magnitude of the emissions and the toxic and chemical characteristics of the pollutants. Recent testing of standard and new technology woodstoves has provided data for developing a family of particulate and carbon monoxide emission factor curves. This testing has also provided data illustrating the acidity of woodstove emissions. The particulate and carbon monoxide curves relate the actual stove emissions to the stove size and operating parameters of burn rate, fuel loading, and fuel moisture. Curves relating stove types to the acidity of emissions have also been constructed. Test data show actual emissions vary from 3 to 50 grams per kilogram for particles and from 50 to 300 grams per kilogram for carbon monoxide. Since woodstove emissions are the largest single category of particulate emissions in many area, it is essential that these emissions be quantified specifically for geographic regions, allowing meaningful impact analysis modeling to be accomplished. Emission factors for particles and carbon monoxide are presented from several stove sizes and burn rates. The acidic nature of woodstove emissions has been clearly demonstrated. Tests indicate woodstove flue gas condensate solutions to be predominantly in the 2.8 to 4.2 pH range. Condensate solutions from conventional woodstoves exhibited the characteristic buffering capacity of carboxylic acids when titrations were performed with a strong base. The environmental impact of buffered acidic woodstove emissions is not currently well understood; however, it is possible with the data presented here to make semi-quantitative estimates of acid emission from particulate and carbon monoxide emission factors and wood use inventories.

  2. Cognitive severity-specific neuronal degenerative network in charcoal burning suicide-related carbon monoxide intoxication: a multimodality neuroimaging study in Taiwan.

    PubMed

    Chen, Nai-Ching; Huang, Chi-Wei; Huang, Shu-Hua; Chang, Wen-Neng; Chang, Ya-Ting; Lui, Chun-Chung; Lin, Pin-Hsuan; Lee, Chen-Chang; Chang, Yen-Hsiang; Chang, Chiung-Chih

    2015-05-01

    While carbon monoxide (CO) intoxication often triggers multiple intraneuronal immune- or inflammatory-related cascades, it is not known whether the pathological processes within the affected regions evolve equally in the long term. To understand the neurodegenerative networks, we examined 49 patients with a clinical diagnosis of CO intoxication related to charcoal burning suicide at the chronic stage and compared them with 15 age- and sex-matched controls. Reconstructions of degenerative networks were performed using T1 magnetic resonance imaging, diffusion-tensor imaging, and fluorodeoxyglucose positron emission tomography (PET). Tract-specific fractional anisotropy (FA) quantification of 11 association fibers was performed while the clinical significance of the reconstructed structural or functional networks was determined by correlating them with the cognitive parameters. Compared with the controls, the patients had frontotemporal gray matter (GM) atrophy, diffuse white matter (WM) FA decrement, and axial diffusivity (AD) increment. The patients were further stratified into 3 groups based on the cognitive severities. The spatial extents within the frontal-insular-caudate GM as well as the prefrontal WM AD increment regions determined the cognitive severities among 3 groups. Meanwhile, the prefrontal WM FA values and PET signals also correlated significantly with the patient's Mini-Mental State Examination score. Frontal hypometabolic patterns in PET analysis, even after adjusted for GM volume, were highly coherent to the GM atrophic regions, suggesting structural basis of functional alterations. Among the calculated major association bundles, only the anterior thalamic radiation FA values correlated significantly with all chosen cognitive scores. Our findings suggest that fronto-insular-caudate areas represent target degenerative network in CO intoxication. The topography that occurred at a cognitive severity-specific level at the chronic phase suggested the

  3. Identical linkage and cooperativity of oxygen and carbon monoxide binding to Octopus dofleini hemocyanin.

    PubMed

    Connelly, P R; Gill, S J; Miller, K I; Zhou, G; van Holde, K E

    1989-02-21

    Employment of high-precision thin-layer methods has enabled detailed functional characterization of oxygen and carbon monoxide binding for (1) the fully assembled form with 70 binding sites and (2) the isolated chains with 7 binding sites of Octopus dofleini hemocyanin. The striking difference in the cooperativities of the two ligands for the assembled decamer is revealed through an examination of the binding capacities and the partition coefficient, determined as functions of the activities of both ligands. A global analysis of the data sets supported a two-state allosteric model assuming an allosteric unit of 7. Higher level allosteric interactions were not indicated. This contrasts to results obtained for arthropod hemocyanins. Oxygen and carbon monoxide experiments performed on the isolated subunit chain confirmed the presence of functional heterogeneity reported previously [Miller, K. (1985) Biochemistry 24, 4582-4586]. The analysis shows two types of binding sites in the ratio of 4:3. PMID:2719937

  4. Identical linkage and cooperativity of oxygen and carbon monoxide binding to Octopus dofleini hemocyanin

    SciTech Connect

    Connelly, P.R.; Gill, S.J.; Miller, K.I.; Zhou, G.; van Holde, K.E. )

    1989-02-21

    Employment of high-precision thin-layer methods has enabled detailed functional characterization of oxygen and carbon monoxide binding for (1) the fully assembled form with 70 binding sites and (2) the isolated chains with 7 binding sites of octopus dofleini hemocyanin. The striking difference in the cooperativities of the two ligands for the assembled decamer is revealed through an examination of the binding capacities and the partition coefficient, determined as functions of the activities of both ligands. A global analysis of the data sets supported by a two-state allosteric model assuming an allosteric unit of 7. Higher level allosteric interactions were not indicated. This contrasts to results obtained for arthropod hemocyanins. Oxygen and carbon monoxide experiments performed on the isolated subunit chain confirmed the presence of functional heterogeneity reported previously. The analysis shows two types of binding sites in the ratio of 4:3.

  5. Effects of xenobiotics on total antioxidant capacity

    PubMed Central

    2012-01-01

    The objective of this article was to review the effects of xenobiotics on total antioxidant capacity (TAC). Measurement of TAC is appropriate for evaluation of the total antioxidant defenses of blood, cells, and different kinds of tissues and organs. TAC is reduced by alcoholism, smoking, and exposure to radiation, herbicides, carbon monoxide, carbon tetrachloride, lead, arsenic, mercury, cadmium, aluminum, and other toxic elements. The test is also an important tool in evaluating environmental and occupational exposure. PMID:23554550

  6. An explanatory model of functional exercise capacity in patients with systemic sclerosis: considerations for rehabilitation programs

    PubMed Central

    Lopes, Agnaldo José; Ferreira, Arthur de Sá; Lima, Tatiana Rafaela Lemos; Menezes, Sara Lucia Silveira; Guimarães, Fernando Silva

    2016-01-01

    [Purpose] This study aimed to evaluate the impact of lung function and peripheral muscle function on the six-minute walking distance (6MWD) in systemic sclerosis (SS) patients and, thereby, to develop an explanatory model of functional exercise capacity for these individuals. [Methods] In a cross-sectional study, 31 SS patients underwent pulmonary function testing (including spirometry, diffusing capacity for carbon monoxide [DLCO], and respiratory muscle strength), isometric dynamometry with surface electromyography, and the 6MWD. [Results] There was a significant correlation between the 6MWD (% predicted, 6MWD%) and the following parameters: height (r = 0.427) and DLCO (r = 0.404). In contrast, no other independent variable showed a significant correlation with the 6MWD% (r ≤ 0.257). The final prediction model for 6MWD% (adjusted R2 = 0.456, SE of bias=12%) was 6MWD% Gibbons = −131.3 + 1.16 × heightcm + 0.33 × DLCO% predicted. [Conclusion] In SS patients, body height and pulmonary diffusion are the main determinants of the 6MWD. Our results justify further investigation of the performance of SS patients during exercise, which may increase the understanding of the pathophysiological mechanisms involved in the disease. The impact of these findings in SS patients may be useful for evaluating the effects of rehabilitation programs. PMID:27065545

  7. CO (Carbon Monoxide Mixing Ratio System) Handbook

    SciTech Connect

    Biraud, S

    2011-02-23

    The main function of the CO instrument is to provide continuous accurate measurements of carbon monoxide mixing ratio at the ARM SGP Central Facility (CF) 60-meter tower (36.607 °N, 97.489 °W, 314 meters above sea level). The essential feature of the control and data acquisition system is to record signals from a Thermo Electron 48C and periodically calibrate out zero and span drifts in the instrument using the combination of a CO scrubber and two concentrations of span gas (100 and 300 ppb CO in air). The system was deployed on May 25, 2005.

  8. Carbon copy deaths: carbon monoxide gas chamber.

    PubMed

    Patel, F

    2008-08-01

    The news media can exert a powerful influence over suicidal behaviour. It has been observed that like-minded individuals are able to preplan a group suicide method using modern communication technology in the form of websites and online chatrooms and mobile phone texting. A case of carbon monoxide (CO) poisoning is presented to illustrate the recent phenomenon of cyber suicides by suffocation from a burning barbecue (charcoal burner) in 'gas chamber' conversions. Although barbecues (BBQ) are very popular in Britain and widely available, there have been relatively few reported cases of copycat deaths from CO gas suffocation. PMID:18586213

  9. Carbon monoxide safety systems for gas appliances

    SciTech Connect

    Goldstein, M.K.; Anderson, T.G.; Palmer, J.G.

    1986-01-01

    Progress in the development of a self-powered carbon monoxide safety control system for application to gas appliances is reported. A comparison of the various possible technologies is made, and the relative strengths and weaknesses of each are discussed. Results of an experimental study of a chemioptical sensor, describing its CO sensitivity, dose response time, reusibility, and dependence on temperature and humidity are presented. The effects of four interfering gasses, ammonia, hydrogen sulfide, acrolein, and formic acid, are also included. Details are shown for a safety control system now undergoing field tests in gas room heaters.

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

    DOEpatents

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

    2012-11-13

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

  11. COSMIC: Carbon Monoxide and Soot in Microgravity Inverse Combustion

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  12. A new interstellar molecule: tricarbon monoxide.

    PubMed

    Matthews, H E; Irvine, W M; Friberg, P; Brown, R D; Godfrey, P D

    1984-07-12

    The cold dark interstellar Taurus Molecular Cloud One (TMC-1) is a rich source of acetylenic and polyacetylenic molecular species. As well as linear closed-shell molecules (H(C triple bond C)nCN) and symmetric rotors (CH3C triple bond CH, CH3C triple bond CCN), several radicals (C triple bond CH, C triple bond CCN, (C triple bond C2H) have also been identified, many of which had not been studied previously in the laboratory. Whether the observed abundances can be understood in terms of purely gas-phase ion-molecule chemical schemes, which produce reasonable agreement for the simplest polyatomic species, is unclear; alternative models involving the particulate interstellar grains as catalysts or sources have also been suggested. We now report the detection in TMC-1 of a new molecule, tricarbon monoxide (C3O), whose pure rotational spectrum has only very recently been studied in the laboratory. As C3O is the first known interstellar carbon chain molecule to contain oxygen, its existence places an important new constraint on chemical schemes for cold interstellar clouds. In fact, the observed abundance of tricarbon monoxide fits quite well into our model of galactochemistry.

  13. Boron monoxide-hydrogen peroxide fuel cell

    SciTech Connect

    Struthers, R.C.

    1985-01-08

    A primary fuel cell including an elongate case defining a central ion exchange compartment with opposite ends and containing a liquid ionolyte. The case next defines an anode section at one end of the case and including a gas compartment containing boron monoxide gas fuel, a liquid compartment between the gas compartment and the ion exchange compartment and containing a liquid anolyte. The ionolyte and anolyte are separated by a cationic membrane. The gas and liquid compartments are separated by an anode plate including an electron collector part, a catalyst material carried by said part and a gas permeable hydrophobic membrane between the boron monoxide gas and the catalyst material. The cell further includes a cathode section at the other end of the case defining a cathode fuel compartment containing a fluid cathode fuel and a cathode plate between and separating the cathode fuel and the ionolyte in the ion exchange compartment. The cathode plate includes an electron distributor part and a catalyst material carried by the distributor part. If the cathode fuel is a gas fuel, the cathode plate also includes a gas permeable hydrophobic membrane between the catalyst material carried by the distributor part and the cathode fuel. The cathode and anode plates have terminals connected with a related external electric circuit.

  14. [Carbon monoxide poisoning by a heating system].

    PubMed

    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.

  15. Volcanic iodine monoxide observed from satellite

    NASA Astrophysics Data System (ADS)

    Schönhardt, Anja; Richter, Andreas; Theys, Nicolas; Burrows, John P.

    2016-04-01

    Halogen species are injected into the atmosphere by volcanic eruptions. Previous studies have reported observations of chlorine and bromine oxides in volcanic plumes. These emissions have a significant impact on the chemistry within the plume as well as on upper troposphere and lower stratosphere composition, e.g. through ozone depletion. Volcanic halogen oxides have been observed from different platforms, from ground, aircraft and from satellite. The present study reports on satellite observations of iodine monoxide, IO, following the eruption of the Kasatochi volcano, Alaska, in August 2008. Satellite measurements from the SCIAMACHY sensor onboard ENVISAT are used. In addition, the volcanic IO plume is also retrieved from GOME-2 / MetOP-A measurements. Largest IO column amounts reach up to more than 4×1013 molec/cm2, the results from both instruments being consistent. The IO plume has a very similar shape as the BrO plume and is observed for several days following the eruption. The present observations are the first evidence that besides chlorine and bromine oxides also iodine oxides can be emitted by volcanic eruptions. This has important implications for atmospheric composition and background iodine levels. Together with the simultaneous observations of BrO and SO2, iodine monoxide columns can possibly provide insights into the composition of the magma.

  16. Hyperbaric oxygen therapy for carbon monoxide poisoning.

    PubMed

    Weaver, Lindell K

    2014-01-01

    Despite established exposure limits and safety standards, and the availability of carbon monoxide (CO) alarms, each year 50,000 people in the United States visit emergency departments for CO poisoning. Carbon monoxide poisoning can occur from brief exposures to high levels of CO, or from longer exposures to lower levels. Common symptoms include headaches, nausea and vomiting, dizziness, general malaise, and altered mental status. Some patients may have chest pain, shortness of breath and myocardial ischemia, and may require mechanical ventilation and treatment of shock. Individuals poisoned by CO often go on to develop neurological problems, including cognitive sequelae, anxiety and depression, persistent headaches, dizziness, sleep problems, motor weakness, vestibular and balance problems, gaze abnormalities, peripheral neuropathies, hearing loss, tinnitus and Parkinsonian-like syndrome. While breathing oxygen hastens the removal of carboxyhemoglobin (COHb), hyperbaric oxygen (HBO2) hastens COHb elimination and favorably modulates inflammatory processes instigated by CO poisoning, an effect not observed with breathing normobaric oxygen. Hyperbaric oxygen improves mitochondrial function, inhibits lipid peroxidation transiently, impairs leukocyte adhesion to injured microvasculature, and reduces brain inflammation caused by the CO-induced adduct formation of myelin basic protein. Based upon three supportive randomized clinical trials in humans and considerable evidence from animal studies, HBO2 should be considered for all cases of acute symptomatic CO poisoning. Hyperbaric oxygen is indicated for CO poisoning complicated by cyanide poisoning, often concomitantly with smoke inhalation.

  17. Fatal carbon monoxide intoxication after acetylene gas welding of pipes.

    PubMed

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

    2013-06-01

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

  18. 40 CFR 52.376 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.376 Control strategy: Carbon... submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base year...

  19. 40 CFR 52.1179 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52.1179 Section 52.1179 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. (a) Approval—On March 18, 1999, the Michigan Department of Environmental...

  20. 40 CFR 52.1340 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52.1340 Section 52.1340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. Approval—A maintenance plan and redesignation request for the St. Louis, Missouri,...

  1. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... interference, system check, and calibration test procedures specified in 40 CFR part 1065 may be used in lieu... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Carbon monoxide analyzer calibration... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR...

  2. 40 CFR 52.2089 - Control strategy: carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: carbon monoxide. 52... strategy: carbon monoxide. (a) Approval—On September 22, 2008, the Rhode Island Department of Environmental Management submitted a request to establish a limited maintenance plan for the Providence Rhode Island...

  3. 40 CFR 52.1340 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52.1340 Section 52.1340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. Approval—A maintenance plan and redesignation request for the St. Louis, Missouri,...

  4. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... interference, system check, and calibration test procedures specified in 40 CFR part 1065 may be used in lieu... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Carbon monoxide analyzer calibration... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR...

  5. 40 CFR 52.785 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Indiana § 52.785 Control strategy: Carbon... for attainment and maintenance of the national standards for carbon monoxide in the...

  6. 40 CFR 60.263 - Standard for carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for carbon monoxide. 60.263... Production Facilities § 60.263 Standard for carbon monoxide. (a) On and after the date on which the... furnace any gases which contain, on a dry basis, 20 or greater volume percent of carbon...

  7. 40 CFR 60.263 - Standard for carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for carbon monoxide. 60.263... Production Facilities § 60.263 Standard for carbon monoxide. (a) On and after the date on which the... furnace any gases which contain, on a dry basis, 20 or greater volume percent of carbon...

  8. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... interference, system check, and calibration test procedures specified in 40 CFR part 1065 may be used in lieu... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR...

  9. 40 CFR 52.376 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.376 Control strategy: Carbon... submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base year...

  10. 40 CFR 52.1340 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52.1340 Section 52.1340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. Approval—A maintenance plan and redesignation request for the St. Louis, Missouri,...

  11. 40 CFR 52.1340 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52.1340 Section 52.1340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. Approval—A maintenance plan and redesignation request for the St. Louis, Missouri,...

  12. 40 CFR 52.785 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Indiana § 52.785 Control strategy: Carbon... for attainment and maintenance of the national standards for carbon monoxide in the...

  13. 40 CFR 52.376 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.376 Control strategy: Carbon... submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base year...

  14. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the American Society for... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ethylene-carbon monoxide copolymers. 177.1312... Use Food Contact Surfaces § 177.1312 Ethylene-carbon monoxide copolymers. The ethylene-carbon...

  15. 40 CFR 52.729 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Illinois> § 52.729 Control strategy: Carbon..., Illinois be granted a carbon monoxide (CO) state implementation plan (SIP) revision with...

  16. 40 CFR 52.376 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.376 Control strategy: Carbon... submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base year...

  17. 40 CFR 52.729 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Illinois> § 52.729 Control strategy: Carbon..., Illinois be granted a carbon monoxide (CO) state implementation plan (SIP) revision with...

  18. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... interference, system check, and calibration test procedures specified in 40 CFR part 1065 may be used in lieu... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Carbon monoxide analyzer calibration... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR...

  19. 40 CFR 52.1179 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52.1179 Section 52.1179 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. (a) Approval—On March 18, 1999, the Michigan Department of Environmental...

  20. 40 CFR 60.263 - Standard for carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for carbon monoxide. 60.263... Production Facilities § 60.263 Standard for carbon monoxide. (a) On and after the date on which the... furnace any gases which contain, on a dry basis, 20 or greater volume percent of carbon...

  1. 40 CFR 52.2089 - Control strategy: carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: carbon monoxide. 52... strategy: carbon monoxide. (a) Approval—On September 22, 2008, the Rhode Island Department of Environmental Management submitted a request to establish a limited maintenance plan for the Providence Rhode Island...

  2. 40 CFR 52.1179 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52.1179 Section 52.1179 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. (a) Approval—On March 18, 1999, the Michigan Department of Environmental...

  3. 40 CFR 52.785 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Indiana § 52.785 Control strategy: Carbon... for attainment and maintenance of the national standards for carbon monoxide in the...

  4. 40 CFR 52.1179 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52.1179 Section 52.1179 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. (a) Approval—On March 18, 1999, the Michigan Department of Environmental...

  5. 40 CFR 52.729 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Illinois> § 52.729 Control strategy: Carbon..., Illinois be granted a carbon monoxide (CO) state implementation plan (SIP) revision with...

  6. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... interference, system check, and calibration test procedures specified in 40 CFR part 1065 may be used in lieu... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR...

  7. 40 CFR 52.1340 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52.1340 Section 52.1340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. Approval—A maintenance plan and redesignation request for the St. Louis, Missouri,...

  8. 40 CFR 52.2089 - Control strategy: carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: carbon monoxide. 52... strategy: carbon monoxide. (a) Approval—On September 22, 2008, the Rhode Island Department of Environmental Management submitted a request to establish a limited maintenance plan for the Providence Rhode Island...

  9. 40 CFR 52.2089 - Control strategy: carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: carbon monoxide. 52... strategy: carbon monoxide. (a) Approval—On September 22, 2008, the Rhode Island Department of Environmental Management submitted a request to establish a limited maintenance plan for the Providence Rhode Island...

  10. 40 CFR 52.2089 - Control strategy: carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: carbon monoxide. 52... strategy: carbon monoxide. (a) Approval—On September 22, 2008, the Rhode Island Department of Environmental Management submitted a request to establish a limited maintenance plan for the Providence Rhode Island...

  11. 40 CFR 60.263 - Standard for carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for carbon monoxide. 60.263... Production Facilities § 60.263 Standard for carbon monoxide. (a) On and after the date on which the... furnace any gases which contain, on a dry basis, 20 or greater volume percent of carbon...

  12. 40 CFR 52.785 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Indiana § 52.785 Control strategy: Carbon... for attainment and maintenance of the national standards for carbon monoxide in the...

  13. 40 CFR 60.263 - Standard for carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for carbon monoxide. 60.263... Production Facilities § 60.263 Standard for carbon monoxide. (a) On and after the date on which the... furnace any gases which contain, on a dry basis, 20 or greater volume percent of carbon...

  14. 40 CFR 52.1179 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52.1179 Section 52.1179 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Carbon monoxide. (a) Approval—On March 18, 1999, the Michigan Department of Environmental...

  15. 40 CFR 52.785 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Indiana § 52.785 Control strategy: Carbon... for attainment and maintenance of the national standards for carbon monoxide in the...

  16. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868.1430 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer....

  17. 40 CFR 52.1581 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New Jersey § 52.1581 Control... New Jersey Department of Environmental Protection as a revision to the carbon monoxide State... carbon monoxide state implementation plan for the New Jersey portion of the New York—Northern New...

  18. 40 CFR 52.1581 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New Jersey § 52.1581 Control... New Jersey Department of Environmental Protection as a revision to the carbon monoxide State... carbon monoxide state implementation plan for the New Jersey portion of the New York—Northern New...

  19. 40 CFR 52.1581 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New Jersey § 52.1581 Control... New Jersey Department of Environmental Protection as a revision to the carbon monoxide State... carbon monoxide state implementation plan for the New Jersey portion of the New York—Northern New...

  20. 40 CFR 52.1581 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New Jersey § 52.1581 Control... New Jersey Department of Environmental Protection as a revision to the carbon monoxide State... carbon monoxide state implementation plan for the New Jersey portion of the New York—Northern New...

  1. 40 CFR 52.1581 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) New Jersey § 52.1581 Control... New Jersey Department of Environmental Protection as a revision to the carbon monoxide State... carbon monoxide state implementation plan for the New Jersey portion of the New York—Northern New...

  2. 40 CFR 86.1322-84 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration... (CONTINUED) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1322-84 Carbon monoxide analyzer calibration. The NDIR carbon...

  3. 40 CFR 86.122-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration... Regulations for 1977 and Later Model Year New Light-Duty Vehicles and New Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles; Test Procedures § 86.122-78 Carbon monoxide analyzer calibration. The...

  4. Carbon monoxide oxidation rates computed for automobile thermal reactor conditions

    NASA Technical Reports Server (NTRS)

    Brokaw, R. S.; Bittker, D. A.

    1972-01-01

    Carbon monoxide oxidation rates in thermal reactors for exhaust manifolds are computed by integrating differential equations for system of twenty-nine reversible chemical reactions. Reactors are noncatalytic replacements for conventional exhaust manifolds and are a system for reducing carbon monoxide and hydrocarbons in automobile exhausts.

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

    ERIC Educational Resources Information Center

    Kolb, Kenneth E.; Kolb, Doris

    1983-01-01

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

  6. Atomic-scale disproportionation in amorphous silicon monoxide

    NASA Astrophysics Data System (ADS)

    Hirata, Akihiko; Kohara, Shinji; Asada, Toshihiro; Arao, Masazumi; Yogi, Chihiro; Imai, Hideto; Tan, Yongwen; Fujita, Takeshi; Chen, Mingwei

    2016-05-01

    Solid silicon monoxide is an amorphous material which has been commercialized for many functional applications. However, the amorphous structure of silicon monoxide is a long-standing question because of the uncommon valence state of silicon in the oxide. It has been deduced that amorphous silicon monoxide undergoes an unusual disproportionation by forming silicon- and silicon-dioxide-like regions. Nevertheless, the direct experimental observation is still missing. Here we report the amorphous structure characterized by angstrom-beam electron diffraction, supplemented by synchrotron X-ray scattering and computer simulations. In addition to the theoretically predicted amorphous silicon and silicon-dioxide clusters, suboxide-type tetrahedral coordinates are detected by angstrom-beam electron diffraction at silicon/silicon-dioxide interfaces, which provides compelling experimental evidence on the atomic-scale disproportionation of amorphous silicon monoxide. Eventually we develop a heterostructure model of the disproportionated silicon monoxide which well explains the distinctive structure and properties of the amorphous material.

  7. Unintentional carbon monoxide poisoning in Colorado, 1986 through 1991.

    PubMed Central

    Cook, M; Simon, P A; Hoffman, R E

    1995-01-01

    Unintentional carbon monoxide poisonings were identified through death certificates, by hyperbaric chambers, and by laboratories required to report carboxyhemoglobin levels greater than 12%. From 1986 to 1991, 981 cases were reported, including 174 deaths. Deaths most often resulted from fire-related carbon monoxide intoxication (36.2%), followed by motor vehicle exhaust (34.5%), and furnaces (10.3%). Among nonfatal cases, furnaces were the leading source of carbon monoxide exposure (44.3%), followed by motor vehicle exhaust (22.8%). The importance of furnaces and other home heating devices in carbon monoxide intoxication may be underappreciated if only mortality data are examined. Surveillance of carbon monoxide-related morbidity is a useful adjunct to mortality surveillance in guiding prevention efforts. PMID:7604927

  8. Search of medical literature for indoor carbon monoxide exposure

    SciTech Connect

    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.

  9. Atomic-scale disproportionation in amorphous silicon monoxide.

    PubMed

    Hirata, Akihiko; Kohara, Shinji; Asada, Toshihiro; Arao, Masazumi; Yogi, Chihiro; Imai, Hideto; Tan, Yongwen; Fujita, Takeshi; Chen, Mingwei

    2016-05-13

    Solid silicon monoxide is an amorphous material which has been commercialized for many functional applications. However, the amorphous structure of silicon monoxide is a long-standing question because of the uncommon valence state of silicon in the oxide. It has been deduced that amorphous silicon monoxide undergoes an unusual disproportionation by forming silicon- and silicon-dioxide-like regions. Nevertheless, the direct experimental observation is still missing. Here we report the amorphous structure characterized by angstrom-beam electron diffraction, supplemented by synchrotron X-ray scattering and computer simulations. In addition to the theoretically predicted amorphous silicon and silicon-dioxide clusters, suboxide-type tetrahedral coordinates are detected by angstrom-beam electron diffraction at silicon/silicon-dioxide interfaces, which provides compelling experimental evidence on the atomic-scale disproportionation of amorphous silicon monoxide. Eventually we develop a heterostructure model of the disproportionated silicon monoxide which well explains the distinctive structure and properties of the amorphous material.

  10. Atomic-scale disproportionation in amorphous silicon monoxide

    PubMed Central

    Hirata, Akihiko; Kohara, Shinji; Asada, Toshihiro; Arao, Masazumi; Yogi, Chihiro; Imai, Hideto; Tan, Yongwen; Fujita, Takeshi; Chen, Mingwei

    2016-01-01

    Solid silicon monoxide is an amorphous material which has been commercialized for many functional applications. However, the amorphous structure of silicon monoxide is a long-standing question because of the uncommon valence state of silicon in the oxide. It has been deduced that amorphous silicon monoxide undergoes an unusual disproportionation by forming silicon- and silicon-dioxide-like regions. Nevertheless, the direct experimental observation is still missing. Here we report the amorphous structure characterized by angstrom-beam electron diffraction, supplemented by synchrotron X-ray scattering and computer simulations. In addition to the theoretically predicted amorphous silicon and silicon-dioxide clusters, suboxide-type tetrahedral coordinates are detected by angstrom-beam electron diffraction at silicon/silicon-dioxide interfaces, which provides compelling experimental evidence on the atomic-scale disproportionation of amorphous silicon monoxide. Eventually we develop a heterostructure model of the disproportionated silicon monoxide which well explains the distinctive structure and properties of the amorphous material. PMID:27172815

  11. Carbon monoxide exposure of subjects with documented cardiac arrhythmias

    SciTech Connect

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

    1992-09-01

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

  12. Forced vital capacity predicts long-term survival for curative-resected NSCLC.

    PubMed

    Guo, Xi; Cao, Hongxin; Xu, Jun; Yu, Jianyu; Zheng, Chunlong; Meng, Long; Du, Jiajun

    2014-09-01

    We conducted a retrospective study in patients with non-small cell lung cancer (NSCLC) who underwent curative lung resection to seek for better lung function parameters associated with long-term survival after lung resection. From January 2006 to December 2008, 470 patients who underwent lung resection with a postoperative diagnosis of NSCLC were studied. Median survival time was 60 months. Patients with pulmonary function values <80 % of predicted were defined as lung function impairment. Patients with impaired vital capacity, maximal voluntary ventilation, forced vital capacity (FVC), forced expiratory volume in one second (FEV1) or diffusion capacity for carbon monoxide (DLCO) had significant shorter overall survival time (P = 0.024; P = 0.026; P < 0.001; P = 0.027; P = 0.007). In univariate analysis, VC, FVC, FEV1 and DLCO were found to have significant effect on overall survival. In multivariate analysis, FVC (HR, 2.029; 95 % CI 1.126-3.659; P = 0.019) was found to be an independent prognostic predictor of long-term overall survival. For cancer-specific survival, FVC (HR 2.404; 95 % CI 1.300-4.445; P = 0.005) was also found to be an independent prognostic predictor in multivariable analysis. Preoperative FVC, rather than FEV1 or DLCO, is an independent prognostic predictor for long-term survival. FVC is not only an indicator of lung function but also of great value for surgeons to predict survival after lung resection.

  13. Improvement in lung diffusion by endothelin A receptor blockade at high altitude.

    PubMed

    de Bisschop, Claire; Martinot, Jean-Benoit; Leurquin-Sterk, Gil; Faoro, Vitalie; Guénard, Hervé; Naeije, Robert

    2012-01-01

    Lung diffusing capacity has been reported variably in high-altitude newcomers and may be in relation to different pulmonary vascular resistance (PVR). Twenty-two healthy volunteers were investigated at sea level and at 5,050 m before and after random double-blind intake of the endothelin A receptor blocker sitaxsentan (100 mg/day) vs. a placebo during 1 wk. PVR was estimated by Doppler echocardiography, and exercise capacity by maximal oxygen uptake (Vo(2 max)). The diffusing capacities for nitric oxide (DL(NO)) and carbon monoxide (DL(CO)) were measured using a single-breath method before and 30 min after maximal exercise. The membrane component of DL(CO) (Dm) and capillary volume (Vc) was calculated with corrections for hemoglobin, alveolar volume, and barometric pressure. Altitude exposure was associated with unchanged DL(CO), DL(NO), and Dm but a slight decrease in Vc. Exercise at altitude decreased DL(NO) and Dm. Sitaxsentan intake improved Vo(2 max) together with an increase in resting and postexercise DL(NO) and Dm. Sitaxsentan-induced decrease in PVR was inversely correlated to DL(NO). Both DL(CO) and DL(NO) were correlated to Vo(2 max) at sea level (r = 0.41-0.42, P < 0.1) and more so at altitude (r = 0.56-0.59, P < 0.05). Pharmacological pulmonary vasodilation improves the membrane component of lung diffusion in high-altitude newcomers, which may contribute to exercise capacity.

  14. Carbon monoxide levels during indoor sporting events -- Cincinnati, 1992--1993

    SciTech Connect

    Not Available

    1994-11-01

    Carbon monoxide (CO) produced by internal combustion engines is an indoor health hazard. High CO levels can occur during indoor sporting events--such as tractor pulls--that involve vehicles modified to achieve high horsepower. In January and March 1992 and January 1993, the Cincinnati Health Department evaluated CO levels during tractor pulls, monster-truck jumps, and a mud race event held in an indoor arena with a seating capacity of approximately 16,000 persons. This report summarizes findings from the evaluations.

  15. Infrared Spectra of High Pressure Carbon Monoxide

    SciTech Connect

    Evans, W J; Lipp, M J; Lorenzana, H E

    2001-09-21

    We report infrared (IR) spectroscopic measurements of carbon monoxide (CO) at high pressures. Although CO is one of the simplest heteronuclear diatomic molecules, it displays surprisingly complex behavior at high pressures and has been the subject of several studies [1-5]. IR spectroscopic studies of high pressures phases of CO provide data complementing results from previous studies and elucidating the nature of these phases. Though a well-known and widely utilized diagnostic of molecular systems, IR spectroscopy presents several experimental challenges to high pressure diamond anvil cell research. We present measurements of the IR absorption bands of CO at high pressures and experimentally illustrate the crucial importance of accurate normalization of IR spectra specially within regions of strong absorptions in diamond.

  16. Airborne intercomparisons of carbon monoxide measurement techniques

    NASA Technical Reports Server (NTRS)

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

    1987-01-01

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

  17. Reduction of Carbon Monoxide. Past Research Summary

    DOE R&D Accomplishments Database

    Schrock, R. R.

    1982-01-01

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

  18. Carbon monoxide exposure from aircraft fueling vehicles.

    PubMed

    McCammon, C S; Halperin, W F; Lemen, R A

    1981-01-01

    Investigators from the National Institute for Occupational Safety and Health observed deficiencies in maintenance of fueling trucks at an international airport. The exhaust system is vented under the front bumper, a standard design on fueling trucks which is intended to minimize the proximity of the exhaust system to the jet fuel in the vehicles. Carbon monoxide levels were measured in the cabs of 17 fueling trucks with windows closed, heaters on, and in different positions relative to the wind. One truck had an average CO level of 300 ppm, two exceeded 100 ppm, five others exceeded 50 ppm, while levels in the other nine averaged less than or equal to 500 ppm. Levels of CO depended on the mechanical condition of the vehicle and the vehicle's orientation to the wind. Stringent maintenance is required as the exhaust design is not fail-safe.

  19. Analysis of GASP carbon monoxide data

    NASA Technical Reports Server (NTRS)

    Wu, M. F.

    1981-01-01

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

  20. Carbon monoxide in the treatment of sepsis.

    PubMed

    Nakahira, Kiichi; Choi, Augustine M K

    2015-12-15

    Carbon monoxide (CO), a low-molecular-weight gas, is endogenously produced in the body as a product of heme degradation catalyzed by heme oxygenase (HO) enzymes. As the beneficial roles of HO system have been elucidated in vitro and in vivo, CO itself has also been reported as a potent cytoprotective molecule. Whereas CO represents a toxic inhalation hazard at high concentration, low-dose exogenous CO treatment (~250-500 parts per million) demonstrates protective functions including but not limited to the anti-inflammatory and antiapoptotic effects in preclinical models of human diseases. Of note, CO exposure confers protection in animal models of sepsis by inhibiting inflammatory responses and also enhancing bacterial phagocytosis in leukocytes. These unique functions of CO including both dampening inflammation and promoting host defense mechanism are mediated by multiple pathways such as autophagy induction or biosynthesis of specialized proresolving lipid mediators. We suggest that CO gas may represent a novel therapy for patients with sepsis.

  1. The atmospheric chemistry of iodine monoxide

    SciTech Connect

    Laszlo, B.; Huie, R.E.

    1995-12-01

    The possible role of iodine on tropospheric ozone arid, more recently, stratospheric ozone has been of considerable interest. There have been, however relatively few experimental determination of the chemistry of the important radical, IO. Laser flash photolysis with two-wavelength transient absorption experiments were performed on N{sub 2}O/I{sub 2}+X{sub 2}/N{sub 2} mixtures (X{sub 2} = halogen) at room temperature and total pressure between 8 and 80 kPa. An extended IO absorption spectrum, experimental rate coefficients of IO+IO, IO+O({sup 3}P), IO+BrO, BrO+I and IO+ClO reactions will be presented. Preliminary results show the atmospheric importance of reaction between alkylperoxy radicals and iodine atoms or iodine monoxide radicals. These reactions seem to be important tropospheric iodine sinks.

  2. Syncope Associated with Carbon Monoxide Poisoning due to Narghile Smoking.

    PubMed

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

    2013-01-01

    Narghile smoking is a traditional method of tobacco use, and it has been practiced extensively for 400 years. Traditionally, narghile smoking is a matter of culture mainly in Middle East, Asia, and Africa. In recent years, its use as a social activity has increased worldwide, especially among young people. Narghile smoking is an unusual cause of carbon monoxide poisoning. Narghile smoking, compared to cigarette smoking, can result in more smoke exposure and greater levels of carbon monoxide. We present an acute syncope case of a 19-year-old male patient who had carbon monoxide poisoning after narghile smoking. PMID:23585971

  3. Carbon monoxide sensor and method of use thereof

    DOEpatents

    McDaniel; Anthony H. , Medlin; J. Will , Bastasz; Robert J.

    2007-09-04

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

  4. Mars in situ propellants: Carbon monoxide and oxygen ignition experiments

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  5. Modeling of exposure to carbon monoxide in fires

    SciTech Connect

    Cagliostro, D.E.

    1980-11-01

    A mathematical model is developed to predict carboxyhemoglobin concentrations in regions of the body for short exposures to carbon monoxide levels expected during escape from aircraft fires. The model includes the respiratory and circulatory dynamics of absorption and distribution of carbon monoxide and carboxyhemoglobin. Predictions of carboxyhemoglobin concentrations are compared to experimental values obtained for human exposures to constant high carbon monoxide levels. Predictions are within 20% of experimental values. For short exposure times, transient concentration effects are predicted. The effect of stress is studied and found to increase carboxyhemoglobin levels substantially compared to a rest state.

  6. 49 CFR 392.66 - Carbon monoxide; use of commercial motor vehicle when detected.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Carbon monoxide; use of commercial motor vehicle... SAFETY REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.66 Carbon monoxide... monoxide; (2) Where carbon monoxide has been detected in the interior of the commercial motor vehicle;...

  7. Measuring Carbon Monoxide in Auto Exhaust by Gas Chromatography.

    ERIC Educational Resources Information Center

    Jaffe, Dan; Herndon, Scott

    1995-01-01

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

  8. An interesting cause of pulmonary emboli: Acute carbon monoxide poisoning

    SciTech Connect

    Sevinc, A.; Savli, H.; Atmaca, H.

    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.

  9. Carbon monoxide poisoning and nonoliguric acute renal failure.

    PubMed Central

    Bessoudo, R.; Gray, J.

    1978-01-01

    Carbon monoxide poisoning in a 37-year-old man was complicated by neurologic damage, skin changes, muscle necrosis and nonoliguric renal failure. The relation between nontraumatic rhabdomyolysis and acute renal failure in carbon monoxide poisoning is reviewed. Recognition of the acute renal failure in such cases is important, for this complication can be fatal; the prognosis is excellent, however, if proper medical management is provided. PMID:679099

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

    SciTech Connect

    Apte, M.G.

    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{degrees}C to 30{degrees}C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.

  11. Iodine Monoxide in the Antarctic Marine Boundary Layer: Recent Discoveries

    NASA Astrophysics Data System (ADS)

    Friess, Udo; Zielcke, Johannes; Pöhler, Denis; Nasse, Jan-Marcus; Platt, Ulrich

    2015-04-01

    Iodine monoxide (IO) is thought to play an important role in the chemistry of the Antarctic marine boundary layer (MBL). Produced either by organic precursors or by inorganic processes, large areas of enhanced IO were detected by satellite not only around the coast of Antarctica, but also over the continent far from the coastal source regions. In the past, several active and passive remote sensing measurements at coastal stations confirmed the presence of IO, which is expected to have a significant impact on the oxidative capacity and the ozone budget in the MBL. We present a summary of recent findings regarding IO in the Antarctic MBL, with a focus on two measurement campaigns conducted at the German Research Station Neumayer (70°S, 8°W), the New Zealand Station Scott Base (177°E, 78°S) and in the marginal sea ice zone of the Wedell Sea onboard the German research vessel Polarstern in austral summer 2011, spring 2012, and winter/spring 2013, respectively. During all three campaigns, IO was measured using a combination of active and passive DOAS remote sensing instruments, including a newly developed mobile open-path cavity-enhanced DOAS instrument. Satellite measurements indicate that the area around Scott Base in the Ross Sea, but also the marginal sea ice zone, are subject to particularly high levels of IO. However, in contrast to previous ground-based and satellite borne observations, we find surprisingly low IO concentrations at Neumayer, Scott Base and in the marginal sea ice zone, with IO being below the detection limit (< 0.5 ppt) of the active DOAS instruments at all times. This raises the question to what extent IO is of importance for the chemistry of the Antarctic MBL.

  12. Carbon monoxide exposure in blast furnace workers.

    PubMed

    Lewis, S; Mason, C; Srna, J

    1992-09-01

    This study investigated the occupational exposure to carbon monoxide (CO) of a group of blast furnace workers from an integrated steelworks, compared to a control group having no significant occupational CO exposure from other areas in the same works. The study was undertaken in 1984 at Port Kembla, New South Wales. Carboxyhaemoglobin (COHb) levels before and after an eight-hour work shift were measured in 98 male steelworkers: 52 from two CO-exposed iron blast furnaces and 46 controls from production areas in the same steelworks. The sample was stratified by smoking habits. Environmental air CO levels had been found to be consistently higher on one furnace than on the other. Absorption of CO from the working environment occurred in workers on the blast furnace with higher CO levels, regardless of smoking habits. On this blast furnace, some readings of COHb levels after a workshift in nonsmokers approached the proposed Australian occupational limit of 5 per cent COHb saturation. Overall, workers with the highest occupational exposure who smoked most heavily had the highest absorption of CO over a work shift. Biological monitoring gives an accurate measure of individual worker 'dose' of CO from all sources. Both environmental monitoring and biological monitoring need to be included as part of a program for controlling occupational CO exposure. PMID:1482718

  13. Carbon monoxide exposure in blast furnace workers.

    PubMed

    Lewis, S; Mason, C; Srna, J

    1992-09-01

    This study investigated the occupational exposure to carbon monoxide (CO) of a group of blast furnace workers from an integrated steelworks, compared to a control group having no significant occupational CO exposure from other areas in the same works. The study was undertaken in 1984 at Port Kembla, New South Wales. Carboxyhaemoglobin (COHb) levels before and after an eight-hour work shift were measured in 98 male steelworkers: 52 from two CO-exposed iron blast furnaces and 46 controls from production areas in the same steelworks. The sample was stratified by smoking habits. Environmental air CO levels had been found to be consistently higher on one furnace than on the other. Absorption of CO from the working environment occurred in workers on the blast furnace with higher CO levels, regardless of smoking habits. On this blast furnace, some readings of COHb levels after a workshift in nonsmokers approached the proposed Australian occupational limit of 5 per cent COHb saturation. Overall, workers with the highest occupational exposure who smoked most heavily had the highest absorption of CO over a work shift. Biological monitoring gives an accurate measure of individual worker 'dose' of CO from all sources. Both environmental monitoring and biological monitoring need to be included as part of a program for controlling occupational CO exposure.

  14. Review: hemodynamic response to carbon monoxide

    SciTech Connect

    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.

  15. Vehicle occupant exposure to carbon monoxide

    SciTech Connect

    Koushki, P.A.; al-Dhowalia, K.H.; Niaizi, S.A. )

    1992-12-01

    This paper focuses on the auto commuting micro-environment and presents typical carbon monoxide (CO) concentrations to which auto commuters in central Riyadh, Saudi Arabia were exposed. Two test vehicles traveling over four main arterial roadways were monitored for inside and outside CO levels during eighty peak and off-peak hours extending over an eight-month period. The relative importance of several variables which explained the variability in CO concentrations inside autos was also assessed. It was found that during peak hours auto commuters were exposed to mean CO levels that ranged from 30 to 40 ppm over trips that typically took between 25 to 40 minutes. The mean ratio of inside to outside CO levels was 0.84. Results of variance component analyses indicated that the most important variables affecting CO concentrations inside autos were, in addition to the smoking of vehicle occupants, traffic volume, vehicle speed, period of day and wind velocity. An increase in traffic volume from 1,000 to 5,000 vehicles per hour (vph) increased mean CO level exposure by 71 percent. An increase in vehicle speed from 14 to 55 km/h reduced mean CO exposure by 36 percent. The number of traffic interruptions had a moderate effect on mean concentrations of CO inside vehicles.

  16. Carbon Monoxide: An Essential Signalling Molecule

    NASA Astrophysics Data System (ADS)

    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).

  17. Mapping carbon monoxide using GPS tracked sensors.

    PubMed

    Milton, Richard; Steed, Anthony

    2007-01-01

    In this paper we discuss a pilot study where we have mapped urban air pollution using mobile carbon monoxide (CO) sensors. Our objective is to use inexpensive Global Positioning System (GPS) receivers to track the sensors and explore CO variations at a fine geographic scale. The critical issue in data processing is the treatment of the imprecise logs from the GPS. By using knowledge about the route and the geometry of the buildings, we are able to increase the position accuracy significantly, while at the same time showing that certain events, such as CO profiles while crossing roads, can be detected with a high degree of accuracy. Comparisons between data from our own mobile sensors and a fixed sensor site show good agreement in the vicinity of the fixed sensor, while at the same time identifying significant CO peaks within 100 m of this location. Using the mobile sensors to collect data along two of the main roads in the area, we are able to show CO variations along an urban canyon for parallel and perpendicular wind directions. Finally, a number of significant sources of CO were discovered during the course of the study, which suggest possible locations for fixed sensor sites in the future. We conclude by discussing the results in the context of the push towards large sensor networks and mobile communications. The potential for ad hoc mobile sensor networks may be very large.

  18. Carbon monoxide measurements at Mace Head, Ireland

    NASA Technical Reports Server (NTRS)

    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.

  19. Myth busting in carbon monoxide poisoning.

    PubMed

    Hampson, Neil B

    2016-02-01

    The evidence supporting many beliefs in medicine is based upon opinion, personal experience, hearsay, or "common knowledge." When one searches for the data supporting oft-quoted facts in medicine, they are sometimes found to be old, incorrect, or nonexistent. Such unsupported facts or beliefs can be termed myths. This minireview will summarize 4 examples of "myth busting" by the author when he has discovered widely held beliefs regarding carbon monoxide (CO) poisoning to be untrue during a 25-year career of research in the field. These include the mistaken beliefs that (1) symptoms correlate with presenting blood carboxyhemoglobin levels, (2) residents are safe from CO poisoning if their home does not contain fuel-burning appliances, (3) carboxyhemoglobin levels must be measured rapidly and on arterial blood, and (4) CO poisoning predisposes to premature long-term death from cardiac disease. In addition to providing the evidence disproving these myths, the importance of going back to the original reference when citing prior work is emphasized.

  20. Effects of carbon monoxide on myocardial ischemia

    SciTech Connect

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

    1991-02-01

    The purpose of this study was to determine whether low doses of carbon monoxide (CO) exacerbate myocardial ischemia during a progressive exercise test. The effect of CO exposure was evaluated using the objective measure of time to development of electrocardiographic changes indicative of ischemia and the subjective measure of time to onset of angina. Sixty-three male subjects (41-75 years) with well-documented coronary artery disease, who had exertional angina pectoris and ischemic ST-segment changes in their electrocardiograms, were studied. Results from three randomized, double-blind test visits (room air, low and high CO) were compared. The effect of CO exposure was determined from the percent difference in the end points obtained on exercise tests performed before and after a 1-hr exposure to room air or CO. A significant dose-response relationship was found for the individual differences in the time to ST end point and angina for the pre-versus postexposure exercise test at the three carboxyhemoglobin levels. These findings demonstrate that low doses of CO produce significant effects on cardiac function during exercise in subjects with coronary artery disease.

  1. A Southern Hemisphere atmospheric history of carbon monoxide from South Pole firn air

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed Central

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

    1981-01-01

    Coburn's differential equation for the uptake of carbon monoxide by hemoglobin and two particular types of solution of this equation were considered and the solutions verified for a group of healthy adults consisting of 73 nonsmoking pedestrians or car passengers exposed to low levels of carbon monoxide as experienced in the city of Lyon. The CO levels at the breathing level and the walking speed of the subjects was continually measured, and the carboxyhemoglobin levels determined at the beginning and the end of each test journey. The values of all the other relevant parameters were also determined. The half-life of carboxyhemoglobin was studied as a function of the degree of activity, the age, the sex and the height of the subjects. Finally a mathematical model was set up to represent a periodic uptake of CO which made it possible to estimate the variations in the carboxyhemoglobin level for any subject during a period of a day or a week without any need to know the initial level. PMID:7333242

  3. Diffusion MRI

    NASA Astrophysics Data System (ADS)

    Fukuyama, Hidenao

    Recent advances of magnetic resonance imaging have been described, especially stressed on the diffusion sequences. We have recently applied the diffusion sequence to functional brain imaging, and found the appropriate results. In addition to the neurosciences fields, diffusion weighted images have improved the accuracies of clinical diagnosis depending upon magnetic resonance images in stroke as well as inflammations.

  4. Carbon Monoxide Oxidation by Clostridium thermoaceticum and Clostridium formicoaceticum

    PubMed Central

    Diekert, Gabriele B.; Thauer, Rudolf K.

    1978-01-01

    Cultures of Clostridium formicoaceticum and C. thermoaceticum growing on fructose and glucose, respectively, were shown to rapidly oxidize CO to CO2. Rates up to 0.4 μmol min−1 mg of wet cells−1 were observed. Carbon monoxide oxidation by cell suspensions was found (i) to be dependent on pyruvate, (ii) to be inhibited by alkyl halides and arsenate, and (iii) to stimulate CO2 reduction to acetate. Cell extracts catalyzed the oxidation of carbon monoxide with methyl viologen at specific rates up to 10 μmol min−1 mg of protein−1 (35°C, pH 7.2). Nicotinamide adenine dinucleotide, nicotinamide adenine dinucleotide phosphate and ferredoxin from C. pasteurianum were ineffective as electron acceptors. The catalytic mechanism of carbon monoxide oxidation was “ping-pong,” indicating that the enzyme catalyzing carbon monoxide oxidation can be present in an oxidized and a reduced form. The oxidized form was shown to react reversibly with cyanide, and the reduced form was shown to react reversibly with alkyl halides: cyanide inactivated the enzyme only in the absence of carbon monoxide, and alkyl halides inactivated it only in the presence of carbon monoxide. Extracts inactivated by alkyl halides were reactivated by photolysis. The findings are interpreted to indicate that carbon monoxide oxidation in the two bacteria is catalyzed by a corrinoid enzyme and that in vivo the reaction is coupled with the reduction of CO2 to acetate. Cultures of C. acidi-urici and C. cylindrosporum growing on hypoxanthine were found not to oxidize CO, indicating that clostridia mediating a corrinoid-independent total synthesis of acetate from CO2 do not possess a CO-oxidizing system. PMID:711675

  5. Acute effects of carbon monoxide on cardiac electrical stability

    SciTech Connect

    Verrier, R.L.; Mills, A.K.; Skornik, W.A. )

    1990-10-01

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

  6. Carbon Monoxide Production Associated with Ineffective Erythropoiesis*

    PubMed Central

    White, Peter; Coburn, Ronald F.; Williams, William J.; Goldwein, Manfred I.; Rother, Mary L.; Shafer, Brenda C.

    1967-01-01

    The rate of endogenous carbon monoxide production (˙Vco), determined by the closed rebreathing system technique, was elevated above the normal range in four of five patients studied with ineffective erythropoiesis (four patients with primary refractory anemia, one with thalassemia). The mean molar ratio of ˙Vco to ˙Vheme (rate of circulating heme catabolism, determined from 51Cr red cell survival curves) was 3.0 ± 0.6 (SE), indicating that most of the CO originated from sources other than circulating erythrocyte hemoglobin, in contrast to previous findings in patients with hemolytic anemia, where ˙Vco paralleled ˙Vheme closely. After administration of glycine-2-14C to these patients, endogenous CO was isolated by washout of body CO stores at high pO2 or by reacting peripheral venous blood samples with ferricyanide. The CO was then oxidized to CO2 by palladium chloride and trapped for counting in a liquid scintillation spectrometer. “Early labeled” peaks of 14CO were demonstrated which paralleled “early labeled” peaks of stercobilin and preceded maximal labeling of circulating heme. Production of “early labeled” 14CO in patients with ineffective erythropoiesis was greatly increased, up to 14 times that found in a normal subject. The increased ˙Vco and “early 14CO” production shown by these patients are presumably related mainly to heme catabolism in the marrow. The possibility exists that hepatic heme and porphyrin compounds may also contribute significantly to ˙Vco, as suggested by the finding of a high ˙Vco in an additional patient with porphyria cutanea tarda. PMID:6074003

  7. Decadal Record of Satellite Carbon Monoxide Observations

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  8. Carbon monoxide and the nervous system.

    PubMed

    Raub, J A; Benignus, V A

    2002-12-01

    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 thereby reducing oxygen (O(2)) delivery to the body's organs and tissues. High COHb concentrations are poisonous. Central nervous system (CNS) effects in individuals suffering acute CO poisoning cover a wide range, depending on severity of exposure: headache, dizziness, weakness, nausea, vomiting, disorientation, confusion, collapse, and coma. At lower concentrations, CNS effects include reduction in visual perception, manual dexterity, learning, driving performance, and attention level. Earlier work is frequently cited to justify the statement that CO exposure sufficient to produce COHb levels of ca. 5% would be sufficient to produce visual sensitivity reduction and various neurobehavioral performance deficits. In a recent literature re-evaluation, however, the best estimate was that [COHb] would have to rise to 15-20% before a 10% reduction in any behavioral or visual measurement could be observed. This conclusion was based on (1) critical review of the literature on behavioral and sensory effects, (2) review and interpretation of the physiological effects of COHb on the CNS, (3) extrapolation from the effects of hypoxic hypoxia to the effects of CO hypoxia, and (4) extrapolation from rat behavioral effects of CO to humans. Also covered in this review article are effects of chronic CO exposure, the discovery of neuroglobin, a summary of the relatively new role for endogenous CO in neurotransmission and vascular homeostasis, groups which might be especially sensitive to CO, and recommendations on further research. The interested reader is directed to other published reviews of the literature on CO and historically seminal references that form our understanding of this ubiquitous gas. PMID

  9. [Assessment of legal capacity and testamentary capacity].

    PubMed

    Dreßing, H; Foerster, K; Leygraf, J; Schneider, F

    2014-11-01

    The assessment of legal capacity and testamentary capacity require thorough knowledge of the legal framework and the relevant case law. This paper explains the concept of the legal capacity to contract and the concept of testamentary capacity with respect to German civil law. The relevance of major mental disorders for the assessment of legal capacity and testamentary capacity is discussed.

  10. Encapsulation kinetics and dynamics of carbon monoxide in clathrate hydrate

    PubMed Central

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

    2014-01-01

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

  11. One-dimensional turbulence model simulations of autoignition of hydrogen/carbon monoxide fuel mixtures in a turbulent jet

    SciTech Connect

    Gupta, Kamlesh G.; Echekki, Tarek

    2011-02-15

    The autoignition of hydrogen/carbon monoxide in a turbulent jet with preheated co-flow air is studied using the one-dimensional turbulence (ODT) model. The simulations are performed at atmospheric pressure based on varying the jet Reynolds number and the oxidizer preheat temperature for two compositions corresponding to varying the ratios of H{sub 2} and CO in the fuel stream. Moreover, simulations for homogeneous autoignition are implemented for similar mixture conditions for comparison with the turbulent jet results. The results identify the key effects of differential diffusion and turbulence on the onset and eventual progress of autoignition in the turbulent jets. The differential diffusion of hydrogen fuels results in a reduction of the ignition delay relative to similar conditions of homogeneous autoignition. Turbulence may play an important role in delaying ignition at high-turbulence conditions, a process countered by the differential diffusion of hydrogen relative to carbon monoxide; however, when ignition is established, turbulence enhances the overall rates of combustion of the non-premixed flame downstream of the ignition point. (author)

  12. Effects of carbon monoxide on myocardial ischemia.

    PubMed Central

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

    1991-01-01

    The purpose of this study was to determine whether low doses of carbon monoxide (CO) exacerbate myocardial ischemia during a progressive exercise test. The effect of CO exposure was evaluated using the objective measure of time to development of electrocardiographic changes indicative of ischemia and the subjective measure of time to onset of angina. Sixty-three male subjects (41-75 years) with well-documented coronary artery disease, who had exertional angina pectoris and ischemic ST-segment changes in their electrocardiograms, were studied. Results from three randomized, double-blind test visits (room air, low and high CO) were compared. The effect of CO exposure was determined from the percent difference in the end points obtained on exercise tests performed before and after a 1-hr exposure to room air or CO. The exposures resulted in postexercise carboxyhemoglobin (COHb) levels of 0.6% +/- 0.3%, 2.0% +/- 0.1%, and 3.9% +/- 0.1%. The results obtained on the 2%-COHb day and 3.9%-COHb day were compared to those on the room air day. There were 5.1% (p = 0.01) and 12.1% (p less than or equal to 0.0001) decreases in the time to development of ischemic ST-segment changes after exposures producing 2.0 and 3.9% COHb, respectively, compared to the control day. In addition, there were 4.2% (p = 0.027) and 7.1% (p = 0.002) decreases in time to the onset of angina after exposures producing 2.0 and 3.9% COHb, respectively, compared to the control day. A significant dose-response relationship was found for the individual differences in the time to ST end point and angina for the pre- versus postexposure exercise tests at the three carboxyhemoglobin levels. These findings demonstrate that low doses of CO produce significant effects on cardiac function during exercise in subjects with coronary artery disease. PMID:2040254

  13. Carbon monoxide on Jupiter and implications for atmospheric convection

    NASA Technical Reports Server (NTRS)

    Prinn, R. G.; Barshay, S. S.

    1977-01-01

    A study of the equilibrium and disequilibrium thermochemistry of the recently discovered carbon monoxide on Jupiter suggests that the presence of this gas in the visible atmosphere is a direct result of very rapid upward mixing from levels in the deep atmosphere where the temperature is about 1100 K and where carbon monoxide is thermodynamically much more stable. As a consequence the observed carbon monoxide mixing ratio is a sensitive function of the vertical eddy mixing coefficient. We infer a value for this latter coefficient which is about three to four orders of magnitude greater than that in the earth's troposphere. This result directly supports existing structural and dynamical theories implying very rapid convection in the deep Jovian atmosphere, driven by an internal heat source.

  14. Carbon Monoxide in the Earth's Atmosphere: Increasing Trend.

    PubMed

    Khalil, M A; Rasmussen, R A

    1984-04-01

    The results of an analysis of more than 60,000 atmospheric measurements of carbon monoxide taken over 3(1/2) years at Cape Meares, Oregon (45 degrees N, 125 degrees W), indicate that the background concentration of this gas is increasing. The rate of increase, although uncertain, is about 6 percent per year on average. Human activities are the likely cause of a substantial portion of this observed increase; however, because of the short atmospheric lifetime of carbon monoxide and the relatively few years of observations, fluctuations of sources and sinks related to the natural variability of climate may have affected the observed trend. Increased carbon monoxide may deplete tropospheric hydroxyl radicals, slowing down the removal of dozens of man-made and anthropogenic trace gases and thus indirectly affecting the earth's climate and possibly the stratospheric ozone layer.

  15. Biological significance of fluctuating concentrations of carbon monoxide

    SciTech Connect

    Saltzman, B.E.; Fox, S.H.

    1986-09-01

    The biological significance of fluctuating concentrations is not well understood. Fluctuation patterns can be approximated as a Fourier series of sine waves of different amplitudes, periods, and phases. A theoretical equation was developed for relating carboxyhemoglobin levels in blood to sine wave exposure patterns of carbon monoxide. It was experimentally validated for rabbits exposed to 50-350 ppm of CO in sine waves of periods from 37 to 280 min. Higher frequency carbon monoxide concentration fluctuations were more highly attenuated in the blood in accordance with the equation. The response may be viewed in a new perspective as a modification of the original fluctuation pattern by the transmittance of the biological window. A simplified method of evaluating biologically effective concentrations for different carbon monoxide fluctuation patterns is proposed.

  16. Terpolymerization of ethylene, sulfur dioxide and carbon monoxide

    DOEpatents

    Johnson, Richard; Steinberg, Meyer

    1981-01-01

    This invention relates to a high molecular weight terpolymer of ethylene, sulfur dioxide and carbon monoxide stable to 280.degree. C. and containing as little as 36 mol % ethylene and about 41-51 mol % 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.degree.-50.degree. C., and at a pressure of about 140 to 680 atmospheres, to initiate polymerization.

  17. Terpolymerization of ethylene, sulfur dioxide and carbon monoxide

    DOEpatents

    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.

  18. The oxidation of carbon monoxide using tin oxide based catalysts

    NASA Technical Reports Server (NTRS)

    Sampson, Christopher F.; Jorgensen, Norman

    1990-01-01

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

  19. An Unusual Cause of Carbon Monoxide Poisoning: Narghile Smoking

    PubMed Central

    Ateş, Alpay; Arikan, Müge; Özgök, Ayşegül

    2016-01-01

    Patient: Male, 27 Final Diagnosis: Carbon monoxide poisoning Symptoms: Dizziness • nausea • Syncope Medication: — Clinical Procedure: O2 treatment Specialty: Anesthesiology Objective: Challenging differential diagnosis Background: Carbon monoxide (CO) poisoning is commonly seen during the winter season in Turkey due to use of charcoal stoves and water heaters, but narghile smoking is a rare cause of CO poisoning. Case Report: In this paper, we report a CO poisoning case caused by narghile smoking. The patient was admitted to the ED with nausea, dizziness, vertigo, and syncope. Conclusions: The diagnosis of CO poisoning depends on suspicious anamnesis. The major treatment of CO poisoning is oxygen supply. PMID:27618983

  20. Severe neurologic impairment and uncommon magnetic resonance imaging findings after carbon monoxide poisoning.

    PubMed

    Hoffmann, Clément; Bouix, Julien; Poyat, Chrystelle; Alhanati, Laure; Tourtier, Jean-Pierre; Falzone, Elisabeth

    2016-01-01

    Carbon monoxide poisoning is the most common cause of fatal poisoning worldwide and can lead to severe brain damages. We report a delayed encephalopathy after a severe carbon monoxide poisoning with uncommon magnetic resonance imaging findings. PMID:26078257

  1. Severe neurologic impairment and uncommon magnetic resonance imaging findings after carbon monoxide poisoning.

    PubMed

    Hoffmann, Clément; Bouix, Julien; Poyat, Chrystelle; Alhanati, Laure; Tourtier, Jean-Pierre; Falzone, Elisabeth

    2016-01-01

    Carbon monoxide poisoning is the most common cause of fatal poisoning worldwide and can lead to severe brain damages. We report a delayed encephalopathy after a severe carbon monoxide poisoning with uncommon magnetic resonance imaging findings.

  2. 40 CFR 52.1627 - Control strategy and regulations: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Carbon monoxide. 52.1627 Section 52.1627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1627 Control strategy and regulations: Carbon monoxide. (a) Part D Approval. The Albuquerque/Bernalillo County carbon monoxide maintenance plan as adopted on April 13, 1995, meets the requirements...

  3. 40 CFR 52.1627 - Control strategy and regulations: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: Carbon monoxide. 52.1627 Section 52.1627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1627 Control strategy and regulations: Carbon monoxide. (a) Part D Approval. The Albuquerque/Bernalillo County carbon monoxide maintenance plan as adopted on April 13, 1995, meets the requirements...

  4. 40 CFR 52.1627 - Control strategy and regulations: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: Carbon monoxide. 52.1627 Section 52.1627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1627 Control strategy and regulations: Carbon monoxide. (a) Part D Approval. The Albuquerque/Bernalillo County carbon monoxide maintenance plan as adopted on April 13, 1995, meets the requirements...

  5. 40 CFR 52.1627 - Control strategy and regulations: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: Carbon monoxide. 52.1627 Section 52.1627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1627 Control strategy and regulations: Carbon monoxide. (a) Part D Approval. The Albuquerque/Bernalillo County carbon monoxide maintenance plan as adopted on April 13, 1995, meets the requirements...

  6. 40 CFR 52.1627 - Control strategy and regulations: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: Carbon monoxide. 52.1627 Section 52.1627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1627 Control strategy and regulations: Carbon monoxide. (a) Part D Approval. The Albuquerque/Bernalillo County carbon monoxide maintenance plan as adopted on April 13, 1995, meets the requirements...

  7. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon monoxide and carbon dioxide... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers....

  8. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Carbon monoxide and carbon dioxide... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers....

  9. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon monoxide and carbon dioxide... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers....

  10. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Carbon monoxide and carbon dioxide... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers....

  11. TES/Aura L2 Carbon Monoxide (CO) Lite Nadir (TL2COLN)

    Atmospheric Science Data Center

    2015-06-16

    TES/Aura L2 Carbon Monoxide (CO) Lite Nadir (TL2COLN) News:  TES News ... Level:  L2 Instrument:  TES/Aura L2 Carbon Monoxide Spatial Coverage:  5.3 km nadir ... OPeNDAP Access:  OPeNDAP Parameters:  Carbon Monoxide Order Data:  Reverb:   Order Data ...

  12. 40 CFR 50.8 - National primary ambient air quality standards for carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standards for carbon monoxide. 50.8 Section 50.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... ambient air quality standards for carbon monoxide. (a) The national primary ambient air quality standards for carbon monoxide are: (1) 9 parts per million (10 milligrams per cubic meter) for an 8-hour...

  13. 40 CFR 50.8 - National primary ambient air quality standards for carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards for carbon monoxide. 50.8 Section 50.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... ambient air quality standards for carbon monoxide. (a) The national primary ambient air quality standards for carbon monoxide are: (1) 9 parts per million (10 milligrams per cubic meter) for an 8-hour...

  14. 40 CFR 52.243 - Interim approval of the Carbon Monoxide plan for the South Coast.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Interim approval of the Carbon Monoxide... § 52.243 Interim approval of the Carbon Monoxide plan for the South Coast. The Carbon Monoxide plan for... such earlier date the State has submitted as a SIP revision a demonstration that the carbon...

  15. 40 CFR 52.243 - Interim approval of the Carbon Monoxide plan for the South Coast.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Interim approval of the Carbon Monoxide... § 52.243 Interim approval of the Carbon Monoxide plan for the South Coast. The Carbon Monoxide plan for... such earlier date the State has submitted as a SIP revision a demonstration that the carbon...

  16. 40 CFR 60.103 - Standard for carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Refineries § 60.103 Standard for carbon monoxide. Each owner or operator of any fluid catalytic cracking unit... the fluid catalytic cracking unit catalyst regenerator will be operated, or 180 days after initial... discharge or cause the discharge into the atmosphere from any fluid catalytic cracking unit...

  17. 40 CFR 60.103 - Standard for carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Refineries § 60.103 Standard for carbon monoxide. Each owner or operator of any fluid catalytic cracking unit... the fluid catalytic cracking unit catalyst regenerator will be operated, or 180 days after initial... discharge or cause the discharge into the atmosphere from any fluid catalytic cracking unit...

  18. AIR QUALITY CRITERIA CARBON MONOXIDE, EXTERNAL REVIEW DRAFT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) promulgates the National Ambient Air Quality Standards (NAAQS) on the basis of scientific information contained in criteria documents. The last air quality criteria document for carbon monoxide (CO) was completed by EPA in 1991. This...

  19. 40 CFR 86.1322-84 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate... be used. (2) Zero the carbon monoxide analyzer with either zero-grade air or zero-grade nitrogen. (3... either zero-grade air or zero-grade nitrogen. (3) Calibrate on each used operating range with a...

  20. 40 CFR 86.1322-84 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate... be used. (2) Zero the carbon monoxide analyzer with either zero-grade air or zero-grade nitrogen. (3... either zero-grade air or zero-grade nitrogen. (3) Calibrate on each used operating range with a...

  1. 40 CFR 52.1185 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or local level in accordance with 40 CFR part 51, subpart T—Conformity to State or Federal... local level in accordance with 40 CFR part 93, subpart B—Determining Conformity of General Federal... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide....

  2. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...,” which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene-carbon monoxide copolymers. 177.1312... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1312 Ethylene-carbon...

  3. 40 CFR 86.222-94 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration. 86.222-94 Section 86.222-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.222-94 Carbon...

  4. 40 CFR 86.222-94 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration. 86.222-94 Section 86.222-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.222-94 Carbon...

  5. 40 CFR 52.1185 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... or local level in accordance with 40 CFR part 51, subpart T—Conformity to State or Federal... local level in accordance with 40 CFR part 93, subpart B—Determining Conformity of General Federal... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide....

  6. 40 CFR 52.349 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SIP. The Clean Air Campaign was approved into the SIP at 40 CFR 52.320(c)(43)(i)(A). (d) Revisions to... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.349 Control strategy:...

  7. 40 CFR 52.1185 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or local level in accordance with 40 CFR part 51, subpart T—Conformity to State or Federal... local level in accordance with 40 CFR part 93, subpart B—Determining Conformity of General Federal... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Carbon monoxide....

  8. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...,” which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-carbon monoxide copolymers. 177.1312... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1312 Ethylene-carbon...

  9. 40 CFR 52.349 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SIP. The Clean Air Campaign was approved into the SIP at 40 CFR 52.320(c)(43)(i)(A). (d) Revisions to... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.349 Control strategy:...

  10. 40 CFR 52.1185 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or local level in accordance with 40 CFR part 51, subpart T—Conformity to State or Federal... local level in accordance with 40 CFR part 93, subpart B—Determining Conformity of General Federal... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Carbon monoxide....

  11. 40 CFR 52.349 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SIP. The Clean Air Campaign was approved into the SIP at 40 CFR 52.320(c)(43)(i)(A). (d) Revisions to... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.349 Control strategy:...

  12. 40 CFR 52.349 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SIP. The Clean Air Campaign was approved into the SIP at 40 CFR 52.320(c)(43)(i)(A). (d) Revisions to... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.349 Control strategy:...

  13. 40 CFR 52.349 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SIP. The Clean Air Campaign was approved into the SIP at 40 CFR 52.320(c)(43)(i)(A). (d) Revisions to... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Carbon monoxide. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.349 Control strategy:...

  14. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...,” which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-carbon monoxide copolymers. 177.1312... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1312 Ethylene-carbon...

  15. 40 CFR 86.222-94 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Carbon monoxide analyzer calibration. 86.222-94 Section 86.222-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.222-94 Carbon...

  16. 40 CFR 52.1185 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or local level in accordance with 40 CFR part 51, subpart T—Conformity to State or Federal... local level in accordance with 40 CFR part 93, subpart B—Determining Conformity of General Federal... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Carbon monoxide....

  17. Cross Sections for Electron Collisions with Carbon Monoxide

    SciTech Connect

    Itikawa, Yukikazu

    2015-03-15

    Cross section data are collected and reviewed for electron collisions with carbon monoxide. Collision processes included are total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational and electronic states, ionization, and dissociation. For each process, recommended values of the cross sections are presented, when possible. The literature has been surveyed through to the end of 2013.

  18. Photoproduction of Carbon Monoxide from Natural Organic Matter

    EPA Science Inventory

    Pioneering studies by Valentine provided early kinetic results that used carbon monoxide (CO) production to evaluate the photodecomposition of aquatic natural organic matter (NOM) . (ES&T 1993 27 409-412). Comparatively few kinetic studies have been conducted of the photodegradat...

  19. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... carbon monoxide analyzer as described in this section. (b) Initial and periodic interference. Prior to... corrective action which may be taken.) (c) Initial and periodic calibration. Prior to its initial use and... (64 percent) is required (see following table). Example calibration points (%) Acceptable...

  20. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... carbon monoxide analyzer as described in this section. (b) Initial and periodic interference. Prior to... corrective action which may be taken.) (c) Initial and periodic calibration. Prior to its initial use and... (64 percent) is required (see following table). Example calibration points (%) Acceptable...

  1. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... carbon monoxide analyzer as described in this section. (b) Initial and periodic interference. Prior to... corrective action which may be taken.) (c) Initial and periodic calibration. Prior to its initial use and... (64 percent) is required (see following table). Example calibration points (%) Acceptable...

  2. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... carbon monoxide analyzer as described in this section. (b) Initial and periodic interference. Prior to... corrective action which may be taken.) (c) Initial and periodic calibration. Prior to its initial use and... (64 percent) is required (see following table). Example calibration points (%) Acceptable...

  3. 40 CFR 86.222-94 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon monoxide analyzer calibration. 86.222-94 Section 86.222-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.222-94 Carbon...

  4. 40 CFR 86.1522 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Carbon monoxide analyzer calibration...) Emission Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and...

  5. 40 CFR 86.1522 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Carbon monoxide analyzer calibration...) Emission Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and...

  6. 40 CFR 86.1522 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Carbon monoxide analyzer calibration...) Emission Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and...

  7. 40 CFR 86.1522 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Carbon monoxide analyzer calibration... Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...

  8. 40 CFR 86.1522 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Carbon monoxide analyzer calibration...) Emission Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and...

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

    EPA Science Inventory

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

  10. School Bus Carbon Monoxide Intrusion. NHTSA Technical Report.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This report presents the findings of a voluntary program conducted over a 10-month period during which school buses were tested for carbon monoxide (CO) levels under different climatological conditions. The objective of the test program was to determine whether or not there are any serious CO intrusion problems or indications of potential problems…

  11. 2010 Final Assessment: Integrated Science Assessment for Carbon Monoxide

    EPA Science Inventory

    Cover of the Integrated Science Assessment (ISA) for Carbon <span class=Monoxide" vspace = "5" hspace="5" align="right" border="1" /> EPA has released the final Integrated Science Assessment (ISA) for ...

  12. Carbon Monoxide Poisoning - Multiple Languages: MedlinePlus

    MedlinePlus

    ... JavaScript. Amharic (amarunya) Arabic (العربية) Chinese - Traditional (繁體中文) French (français) German (Deutsch) Haitian Creole (Kreyol) Hmong (Hmoob) ... Traditional) PDF Centers for Disease Control and Prevention French (français) Carbon Monoxide Poisoning English Fiche d'information ...

  13. 40 CFR 52.1887 - Control strategy: Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Administrative Code. (2) The transportation control plans for the following urban areas: Akron (ozone component... areas: Cincinnati, Cleveland, Columbus and Youngstown. (b) (c) Part D—No Action—USEPA at this time takes no action on the carbon monoxide portions of the plan submitted for the urban areas of Akron...

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

    EPA Science Inventory

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

  15. Effect of carbon monoxide on Swiss albino mice

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

    Times to incapacitation and death and LC50 values were determined for male Swiss albino mice exposed to different concentrations of carbon monoxide in a 4.2 liter hemispherical chamber. These values are compared to values reported in the literature. The LC50 for a 30 minute exposure was 3570 ppm CO.

  16. CARBON MONOXIDE POISONING--A PUBLIC HEALTH PERSPECTIVE.

    EPA Science Inventory

    Carbon monoxide (CO) may be the cause of more than one-half of the fatal poisonings reported in many countries: fatal cases also are grossly under-reported or mis-diagnosed by medical professionals. Therefore, the precise number of individuals who have suffered from CO intoxicat...

  17. Vaneless diffusers

    NASA Astrophysics Data System (ADS)

    Senoo, Y.

    The influence of vaneless diffusers on flow in centrifugal compressors, particularly on surge, is discussed. A vaneless diffuser can demonstrate stable operation in a wide flow range only if it is installed with a backward leaning blade impeller. The circumferential distortion of flow in the impeller disappears quickly in the vaneless diffuser. The axial distortion of flow at the diffuser inlet does not decay easily. In large specific speed compressors, flow out of the impeller is distorted axially. Pressure recovery of diffusers at distorted inlet flow is considerably improved by half guide vanes. The best height of the vanes is a little 1/2 diffuser width. In small specific speed compressors, flow out of the impeller is not much distorted and pressure recovery can be predicted with one-dimensional flow analysis. Wall friction loss is significant in narrow diffusers. The large pressure drop at a small flow rate can cause the positive gradient of the pressure-flow rate characteristic curve, which may cause surging.

  18. Diffuse radiation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A diffuse celestial radiation which is isotropic at least on a course scale were measured from the soft X-ray region to about 150 MeV, at which energy the intensity falls below that of the galactic emission for most galactic latitudes. The spectral shape, the intensity, and the established degree of isotropy of this diffuse radiation already place severe constraints on the possible explanations for this radiation. Among the extragalactic theories, the more promising explanations of the isotropic diffuse emission appear to be radiation from exceptional galaxies from matter antimatter annihilation at the boundaries of superclusters of galaxies of matter and antimatter in baryon symmetric big bang models. Other possible sources for extragalactic diffuse gamma radiation are discussed and include normal galaxies, clusters of galaxies, primordial cosmic rays interacting with intergalactic matter, primordial black holes, and cosmic ray leakage from galaxies.

  19. Diffusion barriers

    NASA Technical Reports Server (NTRS)

    Nicolet, M. A.

    1983-01-01

    The choice of the metallic film for the contact to a semiconductor device is discussed. One way to try to stabilize a contact is by interposing a thin film of a material that has low diffusivity for the atoms in question. This thin film application is known as a diffusion barrier. Three types of barriers can be distinguished. The stuffed barrier derives its low atomic diffusivity to impurities that concentrate along the extended defects of a polycrystalline layer. Sacrificial barriers exploit the fact that some (elemental) thin films react in a laterally uniform and reproducible fashion. Sacrificial barriers have the advantage that the point of their failure is predictable. Passive barriers are those most closely approximating an ideal barrier. The most-studied case is that of sputtered TiN films. Stuffed barriers may be viewed as passive barriers whose low diffusivity material extends along the defects of the polycrystalline host.

  20. [Evaluation of the indication of carbon monoxide in exhaled air].

    PubMed

    Woźniak, Krzysztof; Moes, Alicja; Chadzyński, Radosław; Domagała-Kulawik, Joanna

    2009-01-01

    In spite of intensified antitobacco campaigns and decrease in social acceptance for smoking it is still an important issue. In prevention there is a need to make smokers and non-smoking people aware of a level of exposure to tobacco smoke. One of the objective methods to evaluate this exposition is to measure a concentration of the carbon monoxide in exhaled air. The aim of our study was to evaluate the indication of carbon monoxide in exhaled air. The research was based on examination of 67 patients admitted to admission room in SP CSK, Warsaw. The level of carbon monoxide was measured with Smokerlyzer device in 56 cases (34 women, 22 men). Everyone in this group answered questions concerning a reason of admission to hospital, concomitant diseases, and addiction to smoking and ways of fight against the addiction as far as smokers are concerned. Current smokers answered also questions about their attitude to smoking and filled in Fagerström and Schneider tests. In a group of 67 patients 11 were not able to proceed the test with Smokerlyzer, 5 (45.5%) due to dyspnea, 4 (36.4%) due to lack of a verbal contact. In the group of 56 investigated patients 20 (35.7%) have never smoked, 32 (57.1%) were ex-smokers and 4 (7.1%) were current smokers. 3 (75%) of the smokers have tried to give up smoking 3 times on average. In the Fagerström test their mean came to 3.5 points, what indicates a low level of addiction. The Schneider test averaged out 8 points, what indicates a good motivation to give up smoking. The average of concentration of carbon monoxide in exhaled air came to 8 ppm (1.87% Hb) in this group. In the group of non-smoking patients the level of carbon monoxide came to 1.4 ppm (0.67%Hb). In the group of nonsmoking patients exposed to the tobacco smoke, the level of carbon monoxide came to 3 ppm (1.15%), but the difference was not statistically significant (p > 0.05). The increased CO level in exhaled air is usually caused by smoking cigarettes and exposure to

  1. Alterations of tumor microenvironment by carbon monoxide impedes lung cancer growth

    PubMed Central

    Nemeth, Zsuzsanna; Csizmadia, Eva; Vikstrom, Lisa; Li, Mailin; Bisht, Kavita; Feizi, Alborz; Otterbein, Sherrie; Zuckerbraun, Brian; Costa, Daniel B.; Pandolfi, Pier Paolo; Fillinger, Janos; Döme, Balazs; Otterbein, Leo E.; Wegiel, Barbara

    2016-01-01

    We hypothesized that tumor-associated macrophages (TAMs) are controlled by the diffusible gas carbon monoxide (CO). We demonstrate that induction of apoptosis in lung tumors treated with low doses of CO is associated with increased CD86 expression and activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases (Erk) 1/2 pathway in tumor microenvironment. Presence of CD86-positive cells was required for the anti-tumoral effects of CO in established A549 xenografts. We show that the effects of CO on tumor stroma and reprogramming of macrophages towards the anti-tumoral phenotype is mediated by reactive oxygen species (ROS)-dependent activation of MAPK/Erk1/2-c-myc pathway as well as Notch 1-dependent negative feedback on the metabolic enzyme heme oxygenase-1 (HO-1). We find a similar negative correlation between HO-1 and active MAPK-Erk1/2 levels in human lung cancer specimens. In summary, we describe novel non-cell autonomous mechanisms by which the diffusible gas CO dictates changes in the tumor microenvironment through the modulation of macrophages. PMID:26993595

  2. [Occurrence of carbon monoxide, carbon dioxide and nitrogen oxides during the use of gas stoves].

    PubMed

    Prescher, K E

    1982-01-01

    The concentrations of carbon monoxide, carbon dioxide, nitrogen monoxide and nitrogen dioxide arising from gas burning have been measured under experimental and field conditions. In the test room propane, butane and town-gas have been burned, whereas in the apartments investigated only town-gas has been used. The most important influence on the concentration of the four substances arises from the changes in the burning conditions of the flame. Laboratory experiments have been carried out in the test room with open flames and with an aluminum block or a kettle on the flame. The following results have been obtained: (a) for CO the lowest concentration is obtained with open flames irrespective of the type of gas burned. Higher concentrations have been found with aluminum blocks, whereas the highest concentrations were associated with the use of kettles and pots, (b) the experimental conditions have only a small influence on the CO2 concentration, (c) NO concentrations are influenced by the gas type and by the experimental conditions. They are low with kettles but high with open flames, (d) NO2 concentrations are less influenced by the experimental conditions than are NO concentrations. The results of more than 1000 paired determinations of NO2 in kitchen and other rooms are presented. The concentrations which have been measured using diffusion tubes according to Palmes which were exposed for 48 h, were highest in kitchens of dwellings fully equipped with gas devices (heating, cooking, warming water). The mean value of the concentrations was about 50 micrograms/m3, whereas the mean for dwellings without any gas device has been found to be lower than 20 micrograms/m3. PMID:6820854

  3. Composite catalyst for carbon monoxide and hydrocarbon oxidation

    DOEpatents

    Liu, W.; Flytzani-Stephanopoulos, M.

    1996-03-19

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

  4. Composite catalyst for carbon monoxide and hydrocarbon oxidation

    DOEpatents

    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.

  5. Exergy parametric study of carbon monoxide oxidation in moist air

    NASA Astrophysics Data System (ADS)

    Souidi, Ferhat; Benmalek, Toufik; Yesaad, Billel; Baik, Mouloud

    2015-12-01

    This study aims to analyze the oxidation of carbon monoxide in moist air from the second thermodynamic law aspect. A mathematical model of laminar premixed flame in a stagnation point flow has been achieved by numerical solution of the boundary layer equation using a self-made code. The chemical kinetic mechanism for flameless combustion of fuel, which is a mixture of carbon monoxide, oxygen, and water vapor, is modeled by 34 elementary reactions that incorporate (09) nine chemical species: CO, O, CO2, O2, H2O, H, H2, HO2, and OH. The salient point is that for all the parameters we considered, the exergy of the process is completely destroyed by irreversibilities. From the chemical viewpoint, the OH radical plays an essential role in CO oxidation. This latter point has already been mentioned by previous investigators.

  6. Epidemiological bases for the current ambient carbon monoxide standards.

    PubMed Central

    Kuller, L H; Radford, E P

    1983-01-01

    Carbon monoxide is widely distributed in the environment, and acute or chronic toxic effects may be of considerable public health significance. A review of the basis for current ambient standards is given. Mortality and morbidity studies have been negative or equivocal in relating carbon monoxide levels to health effects, but studies in human subjects with compromised coronary or peripheral circulation support an effect of acute exposure to CO at blood levels equivalent to about 20 ppm over several hours. It is possible that some of the cardiovascular effects of smoking may be related to the high levels of CO in cigarette smoke, but it has been difficult to isolate the contribution of CO independent of the effects of other smoke constituents. PMID:6418540

  7. Stability of a new cubic monoxide of Thorium under pressure

    PubMed Central

    Sun, Weiwei; Luo, Wei; Ahuja, Rajeev

    2015-01-01

    Density functional theory has been applied to elucidate the stability of thorium monoxide (ThO). It is found out that the pressure can stabilize the rocksalt phase of ThO, and the transition pressure is estimated between 14 and 22 GPa. The stability of ThO can be attributed due to the gradually filling 5f orbitals at the expense of 7s and 6d electrons in Th metal. For ThO, the pressure induces stronger Th-O bond reflected by the newly established 6d-2p hybridization which is the dominant cause of its stability. The phonon dispersion curves of the rocksalt phase show the positive frequencies which indicates its dynamical stability. Our successful prediction of the stabilization of the metallic ThO has proposed a route to synthesize novel actinide monoxides. PMID:26337015

  8. Carbon monoxide and methane over Canada: July-August 1990

    SciTech Connect

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

    1994-01-20

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

  9. Catalyst for the methanation of carbon monoxide in sour gas

    DOEpatents

    Kustes, William A.; Hausberger, Arthur L.

    1985-01-01

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

  10. Effect of carbon monoxide and nitrogen dioxide on ICR mice

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

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

  11. Catalysis of carbon monoxide methanation by deep sea manganate minerals

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  12. A METHOD FOR THE DETERMINATION OF DIFFUSION CONSTANTS AND THE CALCULATION OF THE RADIUS AND WEIGHT OF THE HEMOGLOBIN MOLECULE

    PubMed Central

    Northrop, John H.; Anson, M. L.

    1929-01-01

    A method is described for determining the diffusion coefficient of solutes by determining the rate of passage of the solute through a thin porous membrane between two solutions of different concentration. The method has been used to determine the diffusion coefficient of carbon monoxide hemoglobin. This was found to be 0.0420 ± 0.0005 cm.2 per day at 5°C. The molecular weight of carbon monoxide hemoglobin calculated by means of Einstein's equation from this quantity is 68,600 ± 1,000. PMID:19872481

  13. CRISM Observations of Water Vapor and Carbon Monoxide

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

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

  14. An Unusual Cause of Carbon Monoxide Poisoning: Narghile Smoking.

    PubMed

    Ateş, Alpay; Arikan, Müge; Özgök, Ayşegul

    2016-01-01

    BACKGROUND Carbon monoxide (CO) poisoning is commonly seen during the winter season in Turkey due to use of charcoal stoves and water heaters, but narghile smoking is a rare cause of CO poisoning. CASE REPORT In this paper, we report a CO poisoning case caused by narghile smoking. The patient was admitted to the ED with nausea, dizziness, vertigo, and syncope. CONCLUSIONS The diagnosis of CO poisoning depends on suspicious anamnesis. The major treatment of CO poisoning is oxygen supply. PMID:27618983

  15. Acute carbon monoxide poisoning: Emergency management and hyperbaric oxygen therapy

    SciTech Connect

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

    1989-10-01

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

  16. Gas adsorption capacity of wood pellets

    DOE PAGES

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; Lau, A.; Bi, X. T.

    2016-02-03

    In this paper, temperature-programmed desorption (TPD) analysis was used to measure and analyze the adsorption of off-gases and oxygen by wood pellets during storage. Such information on how these gases interact with the material helps in the understanding of the purging/stripping behavior of off-gases to develop effective ventilation strategies for wood pellets. Steam-exploded pellets showed the lowest carbon dioxide (CO2) uptake compared to the regular and torrefied pellets. The high CO2 adsorption capacity of the torrefied pellets could be attributed to their porous structure and therefore greater available surface area. Quantifying the uptake of carbon monoxide by pellets was challengingmore » due to chemical adsorption, which formed a strong bond between the material and carbon monoxide. The estimated energy of desorption for CO (97.8 kJ/mol) was very high relative to that for CO2 (7.24 kJ/mol), demonstrating the mechanism of chemical adsorption and physical adsorption for CO and CO2, respectively. As for oxygen, the strong bonds that formed between the material and oxygen verified the existence of chemical adsorption and formation of an intermediate material.« less

  17. Mobile Carbon Monoxide Monitoring System Based on Arduino-Matlab for Environmental Monitoring Application

    NASA Astrophysics Data System (ADS)

    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.

  18. Demonstrating Diffusion

    ERIC Educational Resources Information Center

    Foy, Barry G.

    1977-01-01

    Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

  19. Relativistic diffusion

    NASA Astrophysics Data System (ADS)

    Haba, Z.

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  20. Defusing Diffusion

    ERIC Educational Resources Information Center

    Dou, Remy; Hogan, DaNel; Kossover, Mark; Spuck, Timothy; Young, Sarah

    2013-01-01

    Diffusion has often been taught in science courses as one of the primary ways by which molecules travel, particularly within organisms. For years, classroom teachers have used the same common demonstrations to illustrate this concept (e.g., placing drops of food coloring in a beaker of water). Most of the time, the main contributor to the motion…

  1. Relativistic diffusion.

    PubMed

    Haba, Z

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  2. Heat capacity in weakly correlated liquids

    SciTech Connect

    Khrustalyov, Yu. V.; Vaulina, O. S.; Koss, X. G.

    2012-12-15

    Previously unavailable numerical data related to the heat capacity in two- and three-dimensional liquid Yukawa systems are obtained by means of fluctuation theory. The relations between thermal conductivity and diffusion constants are numerically studied and discussed. New approximation for heat capacity dependence on non-ideality parameter for weakly correlated systems of particles is proposed. Comparison of the obtained results to the existing theoretical and numerical data is discussed.

  3. Pulmonary mechanics and diffusion after 'shock lung'.

    PubMed Central

    Yernault, J C; Englert, M; Sergysels, R; De Coster, A

    1975-01-01

    Pulmonary function studies performed in seven patients who had recovered from 'shock lung' showed a highly significant decrease of diffusing properties of the lung, a slight loss of lung recoil pressure, and a borderline increase of residual volume with normal vital capacity and total lung capacity. Pulmonary compliance was normal. The interpretation of these findings is discussed. PMID:1145529

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

    PubMed

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

    2012-11-01

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

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

    PubMed

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

    2012-11-01

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

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

    PubMed

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

    2014-06-01

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

  7. Experimental evaluation of the ignition process of carbon monoxide and oxygen in a rocket engine

    NASA Technical Reports Server (NTRS)

    Linne, Diane L.

    1996-01-01

    Carbon monoxide and oxygen ignition boundaries were determined in a spark torch igniter as a function of propellant inlet temperatures. The oxygen temperature was varied from ambient to -258 F, and the carbon monoxide temperature was varied from ambient to -241 F. With the oxygen and carbon monoxide at -253 F and -219 F, respectively, they successfully ignited between mixture ratios of 2.42 and 3.10. Analysis of the results indicated that the lower ignition boundary was more sensitive to oxygen temperature than to carbon monoxide temperature. Another series of tests was performed in a small simulated rocket engine with oxygen at -197 F and carbon monoxide at -193 F. An oxygen/hydrogen flame was used to initiate combustion of the oxygen and carbon monoxide. Tests performed at the optimum operating mixture ratio of 0.55 obtained steady-state combustion in every test.

  8. Carbon monoxide absorption through the oral and nasal mucosae of cynomolgus monkeys

    SciTech Connect

    Schoenfisch, W.H.; Hoop, K.A.

    1980-05-01

    Previous studies have shown that blood levels of carbon monoxide increase during cigarette smoking. It has genrally been assumed that increases in blood levels of carbon monoxide could be interpreted as evidence that deep lung penetration of cigarette smoke had occurred. This study was designed to examine whether increased blood levels of carbon monoxide could result from absorption in the nasal and oral cavitites. The nasal and oral cavities of cynomolgus monkeys were exposed, independently of the lungs, to cigarette smoke under rigorous smoking conditions. Pre- and post-exposure blood levels of carbon monoxide were measured. As a positive control, similar volumes of cigarette smoke were passed directly into the lungs, thus bypassing the oral and nasal cavities, and blood levels of carbon monoxide were again measured. The results inidcate that absorption of carbon monoxide in the oral and nasal cavities is negligible under the heavy smoking regimen employed here, and hence, would be negligible under normal smoking conditions.

  9. [Acute coronary syndrome with impaired left ventricular function in a carbon monoxide poisoning].

    PubMed

    Capilla, E; Pons, F; Poyet, R; Kerebel, S; Jego, C; Louge, P; Cellarier, G-R

    2016-02-01

    Carbon monoxide poisoning is the leading cause of death by poisoning in France. Neuropsychological symptoms are most common. We report on a patient with acute coronary syndrome and transient left ventricular dysfunction in carbon monoxide poisoning. Patient improved under hyperbaric oxygen therapy. Coronary angiography shows no significant lesion leading to myocardial stunning diagnose. Patients exposed to carbon monoxide must have systematic cardiac evaluation with electrocardiogram and dosage of biomarkers.

  10. Deaths caused by carbon monoxide poisoning in an open environment (outdoors)

    SciTech Connect

    DiMaio, V.J.; Dana, S.E.

    1987-11-01

    Three deaths as a result of inhalation of carbon monoxide from the exhaust fumes of automobiles are reported. All deaths occurred outside and not in a structure. The individuals were white males, ages 24 to 26 years. Blood carboxyhemoglobin concentrations ranged from 58 (in a decomposing body) to 81%. The three cases illustrate the fact that even in the outdoors death from carbon monoxide inhalation can occur if an individual is in close proximity to a rich source of carbon monoxide.

  11. Cardiovascular effects of chronic carbon monoxide and high-altitude exposure

    SciTech Connect

    McGrath, J.J. )

    1989-07-01

    At higher altitudes, ambient carbon monoxide levels are increasing with the number of residents and tourists and their use of motor vehicles and heating devices (such as fireplaces, furnaces, and stoves). Although chronic exposure to carbon monoxide or high altitude causes pronounced cardiovascular changes in humans as well as in animals, there is little information on the effects elicited by these stressors combined. Data from acute studies and theoretical considerations suggest that carbon monoxide inhaled at altitude may be more detrimental than carbon monoxide inhaled at sea level. It is not known, however, if the cardiovascular system adapts or deteriorates with continuous, concurrent exposure to carbon monoxide and high altitude. Male laboratory rats were exposed for six weeks in steel barometric chambers to altitudes ranging from 3,300 ft (ambient) to 18,000 ft and to concentrations ranging from 0 to 500 parts per million (ppm)2. Carbon monoxide had no effect on body weight at any altitude. There was a tendency for hematocrit to increase even at the lowest concentration of carbon monoxide (9 ppm), but the increase did not become significant until 100 ppm. At 10,000 ft, there was a tendency for total heart weight to increase in rats inhaling 100 ppm carbon monoxide. Although its effects on the heart at altitude are complex, carbon monoxide, in concentrations of 500 ppm or less, had little effect on the right ventricle; it did not exacerbate any effects due to altitude. There was a tendency for the left ventricle weight to increase with exposure to 35 ppm carbon monoxide at altitude, but the increase was not significant until 100 ppm carbon monoxide. Heart rate, blood pressure, cardiac output, and peripheral resistance were unaffected by exposure to 35 ppm carbon monoxide or 10,000-ft altitude singly or in combination.

  12. Abnormal fingernail beds following carbon monoxide poisoning: a case report and review of the literature

    PubMed Central

    2014-01-01

    Introduction Carbon monoxide poisoning is a very common cause of death in accidental, suicidal, or homicidal cases throughout the world. Fingernail bed manifestation is reported in survivors of carbon monoxide poisoning. Case presentation A 40-year-old Caucasian woman was exposed to carbon monoxide when she was sleeping alone in her one-bedroom apartment; fortunately, the beeps from her First Alert combination smoke and carbon monoxide detector woke her and she was saved from any extensive health issues. The most indicative symptoms experienced were a severe headache, blurred vision, agitation, and confusion. Following contact with the Emergency Responses Services, she was promptly transferred to the hospital via ambulance and was treated with high-flow oxygen on the way. She was discharged from the emergency department on the same day, but carbon monoxide exposure had already had adverse effects on her fingernail beds. The fingernail tips were altered and appeared as if a bite had been taken out of their distal borders. The changes in the tips of her fingernails were significant, but they completely disappeared eight weeks later without any additional treatment. Conclusions Worldwide, carbon monoxide poisoning is a potentially lethal condition that is preventable with educational programs and installation of carbon monoxide detectors in the home setting. Exposure to carbon monoxide frequently goes unrecognized until it is too late and causes silent death. To the best of the authors’ knowledge, this is the first report in the literature of fingernail bed manifestations in a survivor of carbon monoxide poisoning. PMID:25073414

  13. Carbon monoxide poisoning in our homes - report of two survivors from North India.

    PubMed

    Sharma, Amit

    2016-06-01

    Carbon monoxide poisoning can result from, e.g., the use of unvented coal-burning heaters, indoor barbecues, or inhalation of exhaust of vehicles. The latter is sometimes used to commit suicide. The most common presentation of carbon monoxide poisoning is cerebral hypoxia. Despite frequent use of indoor coal-burning heaters and stoves during winter months in the northern part of India, carbon monoxide poisoning has been infrequently reported. We describe two cases of carbon monoxide poisoning who reported to the Emergency Department in the early morning of a winter season with un-witnessed, unexplained development of altered level of consciousness.

  14. Ambient carbon monoxide and the risk of hospitalization due to chronic obstructive pulmonary disease.

    PubMed

    Tian, Linwei; Ho, Kin-fai; Wang, Tong; Qiu, Hong; Pun, Vivian C; Chan, Chi Sing; Louie, Peter K K; Yu, Ignatius T S

    2014-12-15

    Data from recent experimental and clinical studies have indicated that lower concentrations of inhaled carbon monoxide might have beneficial antiinflammatory effects. Inhaled carbon monoxide has the potential to be a therapeutic agent for chronic obstructive pulmonary diseases (COPD). However, population-based epidemiologic studies of environmentally relevant carbon monoxide exposure have generated mixed findings. We conducted a time-series study in Hong Kong to estimate the association of short-term exposure to ambient carbon monoxide with emergency hospitalizations for COPD. We collected daily emergency hospital admission data and air pollution data from January 2001 to December 2007. We used log-linear Poisson models to estimate the associations between daily hospital admissions for COPD and the average daily concentrations of carbon monoxide while controlling for the traffic-related co-pollutants nitrogen dioxide and particulate matter with an aerodynamic diameter less than 2.5 μm. Results showed that ambient carbon monoxide was negatively associated with the risk of hospitalizations for COPD. After adjustment for levels nitrogen dioxide or particulate matter with an aerodynamic diameter less than 2.5 μm, the negative associations of carbon monoxide with COPD hospitalizations became stronger. The risk estimates were similar for female and male subjects. In conclusion, short-term exposure to ambient carbon monoxide was associated with a decreased risk of hospitalization for COPD, which suggests that carbon monoxide exposure provides some acute protection of against exacerbation of COPD.

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

    SciTech Connect

    Rosenthal, L.D.

    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.

  16. Diffusion bonding

    DOEpatents

    Anderson, Robert C.

    1976-06-22

    1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

  17. Genetic Variation of αENaC Influences Lung Diffusion During Exercise in Humans

    PubMed Central

    Baker, Sarah E.; Wheatley, Courtney M.; Cassuto, Nicholas A.; Foxx-Lupo, William T.; Sprissler, Ryan; Snyder, Eric M.

    2011-01-01

    Exercise, decompensated heart failure, and exposure to high altitude have been shown to cause symptoms of pulmonary edema in some, but not all, subjects, suggesting a genetic component to this response. Epithelial Na+ Channels (ENaC) regulate Na+ and fluid reabsorption in the alveolar airspace in the lung. An increase in number and/or activity of ENaC has been shown to increase lung fluid clearance. Previous work has demonstrated common functional genetic variants of the α-subunit of ENaC, including an A→T substitution at amino acid 663 (αA663T). We sought to determine the influence of the T663 variant of αENaC on lung diffusion at rest and at peak exercise in healthy humans. Thirty healthy subjects were recruited for study and grouped according to their SCNN1A genotype [n= 17vs.13, age=25±7vs.30±10yrs., BMI= 23±4vs.25±4kg/m2, V̇O2peak= 95±30vs.100±31%pred., mean±SD, for AA (homozygous for αA663) vs. AT/TT groups (at least one αT663), respectively]. Measures of the diffusing capacity of the lungs for carbon monoxide (DLCO), the diffusing capacity of the lungs for nitric oxide (DLNO), alveolar volume (VA), and alveolar-capillary membrane conductance (DM) were taken at rest and at peak exercise. Subjects expressing the AA polymorphism of ENaC showed a significantly greater percent increase in DLCO and DLNO, and a significantly greater decrease in systemic vascular resistance from rest to peak exercise than those with the AT/TT variant (DLCO=51±12vs.36±17%, DLNO=51±24vs.32±25%, SVR=−67±3vs.−50±8%, p<0.05). The AA ENaC group also tended to have a greater percent increase in DLCO/VA from rest to peak exercise, although this did not reach statistical significance (49±26vs.33±26%, p=0.08). These results demonstrate that genetic variation of the α-subunit of ENaC at amino acid 663 influences lung diffusion at peak exercise in healthy humans, suggesting differences in alveolar Na+ and, therefore, fluid handling. These findings could be important

  18. Mixing ratios of carbon monoxide in the troposphere

    SciTech Connect

    Novelli, P.C.; Steele, L.P. ); Tans, P.P. )

    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.

  19. Membrane topography of anaerobic carbon monoxide oxidation in Rhodocyclus gelatinosus.

    PubMed Central

    Champine, J E; Uffen, R L

    1987-01-01

    Rhodocyclus gelatinosus 1 grows anaerobically in the dark at the expense of carbon monoxide. Topographical studies with methyl viologen as the membrane probe indicated that CO oxidation and H2 production sites were on the cytoplasmic side of the cell membrane. Membrane-associated hydrogen gas production appeared to be a unidirectional reaction. In the dark, strain 1 whole cells oxidized CO and incorporated about 306 pmol of 32Pi into ATP per min per mg of protein. With CO as the sole energy-yielding substrate, cells grew with a low growth yield coefficient of 3.7 g (dry weight) of cells per mg of CO oxidized. PMID:3308854

  20. Carbon Monoxide Retrievals From Short Wave Infrared Observations Of Sciamachy

    NASA Astrophysics Data System (ADS)

    Schreier, Franz; Gimeno-Garcia, Sebastian; Lihtenberg, Gunter; Hess, Michael

    2013-12-01

    For the estimation of vertical column densities from short-wave near infrared nadir observations from SCIA- MACHY (and similar instruments like GOSAT) the “Beer InfraRed Retrieval Algorithm” BIRRA has been developed that performs a nonlinear or separable least squares fit of concentration profile scaling factors along with some auxiliary parameters. Our recent work focuses on improvements with respect to wavelength calibration, a more flexible multiwindow fitting scheme, and a better modeling of SCIAMACHY's channel 8 spectral response function. Here we present results from carbon monoxide retrevials from SCIAMACHY's channel 8 indicating the significant impact of fitting the wavelength shift.

  1. Shock-tube study of carbon monoxide dissociation kinetics

    NASA Technical Reports Server (NTRS)

    Hanson, R. K.

    1974-01-01

    Carbon monoxide dissociation-rate data were obtained over the temperature range 5600-12,000 K. The experiments were conducted with undiluted CO to emphasize rate constants applicable to molecular gas systems. Data were obtained as time-resolved pressure measurements on the end wall of a shock tube and, in some cases, as emission histories of the C2 Swan system (0-0 band) behind incident shock waves. Results confirm the presence of C2 as an intermediate species in CO decomposition.

  2. Pathways and Bioenergetics of Anaerobic Carbon Monoxide Fermentation

    PubMed Central

    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. PMID:26635746

  3. [Severe recurrent carbon monoxide poisoning caused by smoking].

    PubMed

    Rasmussen, Daniel Bech; Jacobsen, Villads Bønding

    2015-01-26

    Carbon monoxide (CO) is an odourless, colourless and toxic gas. Sources of CO include car exhaust, charcoal and tobacco smoke. CO binds to haemoglobin forming carboxyhaemoglobin (COHb). Heavy smokers have COHb levels up to 15%. There are reports of COHb levels of 24,2% caused by tobacco use and 28,7% after narghile smoking. A 54-year-old woman with schizophrenia was admitted at the intensive care unit with COHb levels as high as 35% caused by cigarillo smoking. She also presented with severe thiazide-induced hyponatriaemia and high haemoglobin levels. PMID:25612978

  4. Carbon monoxide fluxes over a managed mountain meadow

    NASA Astrophysics Data System (ADS)

    Hörtnagl, Lukas; Hammerle, Albin; Wohlfahrt, Georg

    2014-05-01

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

  5. Carbon monoxide binding to a fish hemoglobin under photostationary conditions.

    PubMed

    Torkelson, S J; Gibson, Q H

    1978-10-25

    Determinations of carbon monoxide binding curves for hemoglobin from Brevoortia tyrannus under equilibrium and photostationary conditions show that in the light, the curve is shifted to the right and altered in shape. The Bohr effect is much less in the light. The kinetics of the transition between equilibrium and photostationary states has been examined. All of the results are satisfactorily described using the two-state model of Monod, J. Wyman, J., and Changeux, J.P. (1965) J. Mol. Biol. 12, 88-118 with the assumption that light produces an additive increase in the rate of dissociation of ligand from the R and T states. PMID:701255

  6. Detecting the dipole moment of a single carbon monoxide molecule

    SciTech Connect

    Schwarz, A. Köhler, A.; Grenz, J.; Wiesendanger, R.

    2014-07-07

    Using non-contact atomic force microscopy with metallic tips enabled us to detect the electrostatic dipole moment of single carbon monoxide (CO) molecules adsorbed on three very different substrates. The observed distance dependent contrast can be explained by an interplay between the attractive van der Waals interaction and the repulsive electrostatic interaction, respectively, with the latter stemming from antiparallel aligned dipoles in tip and molecule. Our results suggest that metallic as well as CO-functionalized tips are able to probe electrostatic properties of polar molecules and that repulsive dipole-dipole interactions have to be considered when interpreting complex contrast patterns.

  7. Thermal Degradation of Lead Monoxide Filled Polymer Composite Radiation Shields

    SciTech Connect

    Harish, V.; Nagaiah, N.

    2011-07-15

    Lead monoxide filled Isophthalate resin particulate polymer composites were prepared with different filler concentrations and investigated for physical, thermal, mechanical and gamma radiation shielding characteristics. This paper discusses about the thermo gravimetric analysis of the composites done to understand their thermal properties especially the effect of filler concentration on the thermal stability and degradation rate of composites. Pristine polymer exhibits single stage degradation whereas filled composites exhibit two stage degradation processes. Further, the IDT values as well as degradation rates decrease with the increased filler content in the composite.

  8. A 40-year record of Northern Hemisphere atmospheric carbon monoxide concentration and isotope ratios from the firn at Greenland Summit.

    NASA Astrophysics Data System (ADS)

    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.

  9. Influence of surface vacancy defects on the carburisation of Fe 110 surface by carbon monoxide.

    PubMed

    Chakrabarty, Aurab; Bouhali, Othmane; Mousseau, Normand; Becquart, Charlotte S; El-Mellouhi, Fedwa

    2016-07-28

    Adsorption and dissociation of gaseous carbon monoxide (CO) on metal surfaces is one of the most frequently occurring processes of carburisation, known as primary initiator of metal dusting corrosion. Among the various factors that can significantly influence the carburisation process are the intrinsic surface defects such as single surface vacancies occurring at high concentrations due to their low formation energy. Intuitively, adsorption and dissociation barriers of CO are expected to be lowered in the vicinity of a surface vacancy, due to the strong attractive interaction between the vacancy and the C atom. Here the adsorption energies and dissociation pathways of CO on clean and defective Fe 110 surface are explored by means of density functional theory. Interestingly, we find that the O adatom, resulting from the CO dissociation, is unstable in the electron-deficit neighbourhood of the vacancy due to its large electron affinity, and raises the barrier of the carburisation pathway. Still, a full comparative study between the clean surface and the vacancy-defected surface reveals that the complete process of carburisation, starting from adsorption to subsurface diffusion of C, is more favourable in the vicinity of a vacancy defect. PMID:27475389

  10. Influence of surface vacancy defects on the carburisation of Fe 110 surface by carbon monoxide

    NASA Astrophysics Data System (ADS)

    Chakrabarty, Aurab; Bouhali, Othmane; Mousseau, Normand; Becquart, Charlotte S.; El-Mellouhi, Fedwa

    2016-07-01

    Adsorption and dissociation of gaseous carbon monoxide (CO) on metal surfaces is one of the most frequently occurring processes of carburisation, known as primary initiator of metal dusting corrosion. Among the various factors that can significantly influence the carburisation process are the intrinsic surface defects such as single surface vacancies occurring at high concentrations due to their low formation energy. Intuitively, adsorption and dissociation barriers of CO are expected to be lowered in the vicinity of a surface vacancy, due to the strong attractive interaction between the vacancy and the C atom. Here the adsorption energies and dissociation pathways of CO on clean and defective Fe 110 surface are explored by means of density functional theory. Interestingly, we find that the O adatom, resulting from the CO dissociation, is unstable in the electron-deficit neighbourhood of the vacancy due to its large electron affinity, and raises the barrier of the carburisation pathway. Still, a full comparative study between the clean surface and the vacancy-defected surface reveals that the complete process of carburisation, starting from adsorption to subsurface diffusion of C, is more favourable in the vicinity of a vacancy defect.

  11. Ischemic colitis associated with acute carbon monoxide poisoning--a case report.

    PubMed

    Weaver, Lindell K; Deru, Kayla

    2016-01-01

    Carbon monoxide (CO) poisoning is common, but it has rarely been reported to cause ischemic colitis. In this case, a 34-year-old female with depression presented to an emergency department after a period of unconsciousness, with urinary and bowel incontinence, following exposure to car exhaust. Her carboxyhemoglobin level was 23%. She had metabolic acidosis. She was transferred to our facility for hyperbaric oxygen treatment, where she had intractable nausea/vomiting with abdominal pain and bright-red bleeding per rectum. She exhibited lower abdominal tenderness and hypoactive bowel sounds. Vital signs were: temperature 36.8 degrees C; blood pressure 137/ 86 mmHg; heart rate 114 beats/minute; respiratory rate 28 breaths/minute. The patient's electrocardiogram showed sinus tachycardia with T-wave inversions in leads I, aVL and V3-V6. The troponin I level peaked at 3.7 ng/ml. Echocardiogram showed a reduced ejection fraction of 30%-35%, with akinesis in the posterior lateral and distal anterior distributions. Computed tomography of the abdomen revealed diffuse colonic mural thickening, supporting mesenteric ischemia. Sigmoidoscopy showed edematous friable pale mucosa from rectum to distal sigmoid colon. Hyperbaric oxygen was deferred based on the patient's status. Over three days, the initial hematochezia progressed to melena and then resolved. Adenosine cardiac stress MRI was normal. She was transferred to the psychiatry service and discharged four days later. Four years later, she has no gastrointestinal, cardiac or cognitive problems. PMID:27265995

  12. Ischemic colitis associated with acute carbon monoxide poisoning--a case report.

    PubMed

    Weaver, Lindell K; Deru, Kayla

    2016-01-01

    Carbon monoxide (CO) poisoning is common, but it has rarely been reported to cause ischemic colitis. In this case, a 34-year-old female with depression presented to an emergency department after a period of unconsciousness, with urinary and bowel incontinence, following exposure to car exhaust. Her carboxyhemoglobin level was 23%. She had metabolic acidosis. She was transferred to our facility for hyperbaric oxygen treatment, where she had intractable nausea/vomiting with abdominal pain and bright-red bleeding per rectum. She exhibited lower abdominal tenderness and hypoactive bowel sounds. Vital signs were: temperature 36.8 degrees C; blood pressure 137/ 86 mmHg; heart rate 114 beats/minute; respiratory rate 28 breaths/minute. The patient's electrocardiogram showed sinus tachycardia with T-wave inversions in leads I, aVL and V3-V6. The troponin I level peaked at 3.7 ng/ml. Echocardiogram showed a reduced ejection fraction of 30%-35%, with akinesis in the posterior lateral and distal anterior distributions. Computed tomography of the abdomen revealed diffuse colonic mural thickening, supporting mesenteric ischemia. Sigmoidoscopy showed edematous friable pale mucosa from rectum to distal sigmoid colon. Hyperbaric oxygen was deferred based on the patient's status. Over three days, the initial hematochezia progressed to melena and then resolved. Adenosine cardiac stress MRI was normal. She was transferred to the psychiatry service and discharged four days later. Four years later, she has no gastrointestinal, cardiac or cognitive problems.

  13. Prediction of the Rate of Uptake of Carbon Monoxide From Blood by Extravascular Tissues

    PubMed Central

    Bruce, Eugene N.; Bruce, Margaret C.; Erupaka, Kinnera

    2008-01-01

    Uptake of environmental carbon monoxide (CO) via the lungs raises the CO content of blood and of myoglobin (Mb)-containing tissues, but the blood-to-tissue diffusion coefficient for CO (DmCO) and tissue CO content are not easily measurable in humans. We used a multicompartment mathematical model to predict the effects of different values of DmCO on the time courses and magnitudes of CO content of blood and Mb-containing tissues when various published experimental studies were simulated. The model enhances our earlier model by adding mass balance equations for oxygen and by dividing the muscle compartment into 2 subcompartments. We found that several published experimental findings are compatible with either fast or slow rates of blood-tissue transfer of CO, whereas others are only compatible with slow rates of tissue uptake of CO. We conclude that slow uptake is most consistent with all of the experimental data. Slow uptake of CO by tissue is primarily due to the very small blood-to-tissue partial pressure gradients for CO. PMID:18313993

  14. DIFFUSION PUMP

    DOEpatents

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  15. Uncovering a dynamically formed substrate access tunnel in carbon monoxide dehydrogenase/acetyl-CoA synthase.

    PubMed

    Wang, Po-hung; Bruschi, Maurizio; De Gioia, Luca; Blumberger, Jochen

    2013-06-26

    The transport of small ligands to active sites of proteins is the basis of vital processes in biology such as enzymatic catalysis and cell signaling, but also of more destructive ones including enzyme inhibition and oxidative damage. Here, we show how a diffusion-reaction model solved by means of molecular dynamics and density functional theory calculations provides novel insight into the transport of small ligands in proteins. In particular, we unravel the existence of an elusive, dynamically formed gas channel, which CO2 takes to diffuse from the solvent to the active site (C-cluster) of the bifunctional multisubunit enzyme complex carbon monoxide dehydrogenase/acetyl-CoA synthase (CODH/ACS). Two cavities forming this channel are temporarily created by protein fluctuations and are not apparent in the X-ray structures. The ligand transport is controlled by two residues at the end of this tunnel, His113 and His116, and occurs on the same time scale on which chemical binding to the active site takes place (0.1-1 ms), resulting in an overall binding rate on the second time scale. We find that upon reduction of CO2 to CO, the newly formed Fe-hydroxy ligand greatly strengthens the hydrogen-bond network, preventing CO from exiting the protein through the same way that CO2 takes to enter the protein. This is the basis for directional transport of CO from the production site (C-cluster of CODH subunit) to the utilization site (A-cluster of ACS subunit). In view of these results, a general picture emerges of how large proteins guide small ligands toward their active sites.

  16. Uncovering a dynamically formed substrate access tunnel in carbon monoxide dehydrogenase/acetyl-CoA synthase.

    PubMed

    Wang, Po-hung; Bruschi, Maurizio; De Gioia, Luca; Blumberger, Jochen

    2013-06-26

    The transport of small ligands to active sites of proteins is the basis of vital processes in biology such as enzymatic catalysis and cell signaling, but also of more destructive ones including enzyme inhibition and oxidative damage. Here, we show how a diffusion-reaction model solved by means of molecular dynamics and density functional theory calculations provides novel insight into the transport of small ligands in proteins. In particular, we unravel the existence of an elusive, dynamically formed gas channel, which CO2 takes to diffuse from the solvent to the active site (C-cluster) of the bifunctional multisubunit enzyme complex carbon monoxide dehydrogenase/acetyl-CoA synthase (CODH/ACS). Two cavities forming this channel are temporarily created by protein fluctuations and are not apparent in the X-ray structures. The ligand transport is controlled by two residues at the end of this tunnel, His113 and His116, and occurs on the same time scale on which chemical binding to the active site takes place (0.1-1 ms), resulting in an overall binding rate on the second time scale. We find that upon reduction of CO2 to CO, the newly formed Fe-hydroxy ligand greatly strengthens the hydrogen-bond network, preventing CO from exiting the protein through the same way that CO2 takes to enter the protein. This is the basis for directional transport of CO from the production site (C-cluster of CODH subunit) to the utilization site (A-cluster of ACS subunit). In view of these results, a general picture emerges of how large proteins guide small ligands toward their active sites. PMID:23713976

  17. Comparative Analysis of Carbon Monoxide Tolerance among Thermoanaerobacter Species.

    PubMed

    Alves, Joana I; Alves, M Madalena; Plugge, Caroline M; Stams, Alfons J M; Sousa, Diana Z

    2016-01-01

    An anaerobic thermophilic strain (strain PCO) was isolated from a syngas-converting enrichment culture. Syngas components cannot be used by strain PCO, but the new strain is very tolerant to carbon monoxide (pCO = 1.7 × 10(5) Pa, 100% CO). 16S rRNA gene analysis and DNA-DNA hybridization revealed that strain PCO is a strain of Thermoanaerobacter thermohydrosulfuricus. The physiology of strain PCO and other Thermoanaerobacter species was compared, focusing on their tolerance to carbon monoxide. T. thermohydrosulfuricus, T. brockii subsp. finnii, T. pseudethanolicus, and T. wiegelii were exposed to increased CO concentrations in the headspace, while growth, glucose consumption and product formation were monitored. Remarkably, glucose conversion rates by Thermoanaerobacter species were not affected by CO. All the tested strains fermented glucose to mainly lactate, ethanol, acetate, and hydrogen, but final product concentrations differed. In the presence of CO, ethanol production was generally less affected, but H2 production decreased with increasing CO partial pressure. This study highlights the CO resistance of Thermoanaerobacter species. PMID:27621723

  18. Combustion characteristics of hydrogen. Carbon monoxide based gaseous fuels

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

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

  19. Comparative Analysis of Carbon Monoxide Tolerance among Thermoanaerobacter Species

    PubMed Central

    Alves, Joana I.; Alves, M. Madalena; Plugge, Caroline M.; Stams, Alfons J. M.; Sousa, Diana Z.

    2016-01-01

    An anaerobic thermophilic strain (strain PCO) was isolated from a syngas-converting enrichment culture. Syngas components cannot be used by strain PCO, but the new strain is very tolerant to carbon monoxide (pCO = 1.7 × 105 Pa, 100% CO). 16S rRNA gene analysis and DNA-DNA hybridization revealed that strain PCO is a strain of Thermoanaerobacter thermohydrosulfuricus. The physiology of strain PCO and other Thermoanaerobacter species was compared, focusing on their tolerance to carbon monoxide. T. thermohydrosulfuricus, T. brockii subsp. finnii, T. pseudethanolicus, and T. wiegelii were exposed to increased CO concentrations in the headspace, while growth, glucose consumption and product formation were monitored. Remarkably, glucose conversion rates by Thermoanaerobacter species were not affected by CO. All the tested strains fermented glucose to mainly lactate, ethanol, acetate, and hydrogen, but final product concentrations differed. In the presence of CO, ethanol production was generally less affected, but H2 production decreased with increasing CO partial pressure. This study highlights the CO resistance of Thermoanaerobacter species. PMID:27621723

  20. Comparative Analysis of Carbon Monoxide Tolerance among Thermoanaerobacter Species

    PubMed Central

    Alves, Joana I.; Alves, M. Madalena; Plugge, Caroline M.; Stams, Alfons J. M.; Sousa, Diana Z.

    2016-01-01

    An anaerobic thermophilic strain (strain PCO) was isolated from a syngas-converting enrichment culture. Syngas components cannot be used by strain PCO, but the new strain is very tolerant to carbon monoxide (pCO = 1.7 × 105 Pa, 100% CO). 16S rRNA gene analysis and DNA-DNA hybridization revealed that strain PCO is a strain of Thermoanaerobacter thermohydrosulfuricus. The physiology of strain PCO and other Thermoanaerobacter species was compared, focusing on their tolerance to carbon monoxide. T. thermohydrosulfuricus, T. brockii subsp. finnii, T. pseudethanolicus, and T. wiegelii were exposed to increased CO concentrations in the headspace, while growth, glucose consumption and product formation were monitored. Remarkably, glucose conversion rates by Thermoanaerobacter species were not affected by CO. All the tested strains fermented glucose to mainly lactate, ethanol, acetate, and hydrogen, but final product concentrations differed. In the presence of CO, ethanol production was generally less affected, but H2 production decreased with increasing CO partial pressure. This study highlights the CO resistance of Thermoanaerobacter species.

  1. Material processing with hydrogen and carbon monoxide on Mars

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

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

  2. A carbon monoxide passive sampler: Research and development needs

    SciTech Connect

    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.

  3. Characterization and purification of carbon monoxide dehydrogenase from Methanosarcina barkeri.

    PubMed Central

    Krzycki, J A; Zeikus, J G

    1984-01-01

    Carbon monoxide-dependent production of H2, CO2, and CH4 was detected in crude cell extracts of acetate-grown Methanosarcina barkeri. This metabolic transformation was associated with an active methyl viologen-linked CO dehydrogenase activity (5 to 10 U/mg of protein). Carbon monoxide dehydrogenase activity was inhibited 85% by 10 microM KCN and was rapidly inactivated by O2. The enzyme was nearly homogeneous after 20-fold purification, indicating that a significant proportion of soluble cell protein was CO dehydrogenase (ca. 5%). The native purified enzyme displayed a molecular weight of 232,000 and a two-subunit composition of 92,000 and 18,000 daltons. The enzyme was shown to contain nickel by isolation of radioactive CO dehydrogenase from cells grown in 63Ni. Analysis of enzyme kinetic properties revealed an apparent Km of 5 mM for CO and a Vmax of 1,300 U/mg of protein. The spectral properties of the enzyme were similar to those published for CO dehydrogenase from acetogenic anaerobes. The physiological functions of the enzyme are discussed. Images PMID:6425262

  4. Carbon monoxide and ST-elevation myocardial infarction: case reports.

    PubMed

    Sward, Douglas G; Sethuraman, Kinjal N; Wong, Jennifer S; Rosenthal, Robert E

    2016-01-01

    We describe two cases of myocardial infarction with ST-segment elevation on electrocardiogram associated with carbon monoxide (CO) poisoning, a condition rarely reported in the literature. The first was a 62-year-old woman who experienced chest pain in the emergency department (ED) while being assessed for exposure to carbon monoxide in her home. The second was an 80-year-old man who fainted at home and was found to have ST elevation during the ED workup. After hospitalization, he returned home and soon thereafter had difficulty walking and speaking. The responding paramedics detected a very high CO level in the home. Both patients received hyperbaric oxygen therapy within the first several hours of presentation. For this combination of conditions, it is difficult to derive evidence-based management recommendations, given the paucity of cases reported to date. We conclude that rapid consultation with interventional cardiology and consideration of angioplasty or stenting are appropriate, especially when electrocardiographic findings and echocardiography point to a specific coronary distribution. Hyperbaric oxygen therapy might have a role in the treatment, based on its effects on myocardial ischemia and injury in other models.

  5. Secondhand cigarette smoke as a cause of chronic carbon monoxide poisoning

    SciTech Connect

    Kachulis, C.J.

    1981-07-01

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

  6. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Localized high concentrations-carbon... Localized high concentrations—carbon monoxide. (a) Not later than October 1, 1975, the Commonwealth shall... quality standards for carbon monoxide. Once such localized areas have been identified, the...

  7. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Localized high concentrations-carbon... Localized high concentrations—carbon monoxide. (a) Not later than October 1, 1975, the Commonwealth shall... quality standards for carbon monoxide. Once such localized areas have been identified, the...

  8. 77 FR 8252 - Adequacy Status of the Anchorage, Alaska, Carbon Monoxide Maintenance Plan for Transportation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... AGENCY Adequacy Status of the Anchorage, Alaska, Carbon Monoxide Maintenance Plan for Transportation... budget (MVEB) in the Anchorage, Alaska, Carbon Monoxide (CO) Maintenance Plan, submitted by the State of... notice of EPA's adequacy finding regarding the motor vehicle emissions budget (MVEB) in the...

  9. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Localized high concentrations-carbon... Localized high concentrations—carbon monoxide. (a) Not later than October 1, 1975, the Commonwealth shall... quality standards for carbon monoxide. Once such localized areas have been identified, the...

  10. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Localized high concentrations-carbon... Localized high concentrations—carbon monoxide. (a) Not later than October 1, 1975, the Commonwealth shall... quality standards for carbon monoxide. Once such localized areas have been identified, the...

  11. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Localized high concentrations-carbon... Localized high concentrations—carbon monoxide. (a) Not later than October 1, 1975, the Commonwealth shall... quality standards for carbon monoxide. Once such localized areas have been identified, the...

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

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

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

  13. 40 CFR 415.440 - Applicability; description of the lead monoxide production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 30 2012-07-01 2012-07-01 false Applicability; description of the lead... CATEGORY Lead Monoxide Production Subcategory § 415.440 Applicability; description of the lead monoxide... of pollutants into treatment works which are publicly owned resulting from the production of...

  14. 40 CFR 415.440 - Applicability; description of the lead monoxide production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Applicability; description of the lead... CATEGORY Lead Monoxide Production Subcategory § 415.440 Applicability; description of the lead monoxide... of pollutants into treatment works which are publicly owned resulting from the production of...

  15. Tristetraprolin mediates anti-inflammatory effects of carbon monoxide on lipopolysaccharide-induced acute lung injury.

    PubMed

    Joe, Yeonsoo; Kim, Seul-Ki; Chen, Yingqing; Yang, Jung Wook; Lee, Jeong-Hee; Cho, Gyeong Jae; Park, Jeong Woo; Chung, Hun Taeg

    2015-11-01

    Low-dose inhaled carbon monoxide is reported to suppress inflammatory responses and exhibit a therapeutic effect in models of lipopolysaccharide (LPS)-induced acute lung injury (ALI). However, the precise mechanism by which carbon monoxide confers protection against ALI is not clear. Tristetraprolin (TTP; official name ZFP36) exerts anti-inflammatory effects by enhancing decay of proinflammatory cytokine mRNAs. With the use of TTP knockout mice, we demonstrate here that the protection by carbon monoxide against LPS-induced ALI is mediated by TTP. Inhalation of carbon monoxide substantially increased the pulmonary expression of TTP. carbon monoxide markedly enhanced the decay of mRNA-encoding inflammatory cytokines, blocked the expression of inflammatory cytokines, and decreased tissue damage in LPS-treated lung tissue. Moreover, knockout of TTP abrogated the anti-inflammatory and tissue-protective effects of carbon monoxide in LPS-induced ALI. These results suggest that carbon monoxide-induced TTP mediates the protective effect of carbon monoxide against LPS-induced ALI by enhancing the decay of mRNA encoding proinflammatory cytokines.

  16. Iron and carbon monoxide enhance coagulation and attenuate fibrinolysis by different mechanisms.

    PubMed

    Nielsen, Vance G; Pretorius, Etheresia

    2014-10-01

    Two parallel lines of investigation elucidating novel mechanisms by which iron (scanning electron microscopy-based) and carbon monoxide (viscoelastic-based) enhance coagulation and diminish fibrinolysis have emerged over the past few years. However, a multimodal approach to ascertain the effects of iron and carbon monoxide remained to be performed. Such investigation could be important, as iron and carbon monoxide are two of the products of heme catabolism via heme oxygenase-1, an enzyme upregulated in a variety of disease states associated with thrombophilia. Human plasma was exposed to ferric chloride, carbon monoxide derived from carbon monoxide-releasing molecule-2, or their combination. Viscoelastic studies demonstrated ferric chloride and carbon monoxide mediated enhancement of velocity of growth, and final clot strength, with the combination of the two molecules noted to have all the prothrombotic kinetic effects of either separately. Parallel ultrastructural studies demonstrated separate types of fibrin polymer cross-linking and matting in plasma exposed to ferric chloride and carbon monoxide, with the combination sharing features of each molecule. In conclusion, we present the first evidence that iron and carbon monoxide interact with key coagulation and fibrinolytic processes, resulting in thrombi that begin to form more quickly, grow faster, become stronger, and are more resistant to lysis.

  17. 40 CFR 51.241 - Nonattainment areas for carbon monoxide and ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Intergovernmental Consultation Agency Designation § 51.241 Nonattainment areas for carbon monoxide and ozone. (a... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Nonattainment areas for carbon monoxide and ozone. 51.241 Section 51.241 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  18. 76 FR 54293 - Review of National Ambient Air Quality Standards for Carbon Monoxide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-31

    ... August 31, 2011 Part II Environmental Protection Agency 40 CFR Parts 50, 53 and 58 Review of National..., 53 and 58 RIN 2060-AI43 Review of National Ambient Air Quality Standards for Carbon Monoxide AGENCY... and the national ambient air quality standards (NAAQS) for carbon monoxide (CO). Based on its...

  19. Method of removing nitrogen monoxide from a nitrogen monoxide-containing gas using a water-soluble iron ion-dithiocarbamate, xanthate or thioxanthate

    DOEpatents

    Liu, D. Kwok-Keung; Chang, Shih-Ger

    1987-08-25

    The present invention relates to a method of removing of nitrogen monoxide from a nitrogen monoxide-containing gas which method comprises contacting a nitrogen oxide-containing gas with an aqueous solution of water soluble organic compound-iron ion chelate complex. The NO absorption efficiency of ferrous urea-dithiocarbamate and ferrous diethanolamine-xanthate as a function of time, oxygen content and solution ph is presented. 3 figs., 1 tab.

  20. Adsorption of carbon monoxide by samples of soils and peat-sand mixtures

    NASA Astrophysics Data System (ADS)

    Smagin, A. V.; Sadovnikova, N. B.; Mazanova, V. S.; Dolzhich, A. R.

    2009-11-01

    The adsorption of carbon monoxide (CO) by loose samples of natural soils and artificial organomineral mixtures depending on the water content was studied in laboratory experiments. The highest adsorption of CO was found for the samples of 100% organic soil modifier and its 80% mixture with sand (200 µg of CO/kg per hour and more). The lowest CO adsorption (10-15 µg of CO/kg per hour) was observed for an Arenosol. The addition of 5 wt % of the modifier to the desert sand increased the adsorption of CO to 50-55 µg of CO/kg per hour, as was typical for the chernozem and soddy-podzolic soil. The adsorption of CO as depending on the water content in the samples was a unimodal function, and the adsorption levels corresponded to the optimum soil water content (about 0.4-0.6 of the maximum water capacity). On the basis of the results, the Arid Grow soil modifier was recommended as a highly efficient agent for the regulation of the gas function of soils in urban areas subjected to increased CO emissions from vehicles and industrial enterprises.

  1. Toxicological approach to setting spacecraft maximum allowable concentrations for carbon monoxide

    NASA Technical Reports Server (NTRS)

    Wong, K. L.; Limero, T. F.; James, J. T.

    1992-01-01

    The Spacecraft Maximum Allowable Concentrations (SMACs) are exposure limits for airborne chemicals used by NASA in spacecraft. The aim of these SMACs is to protect the spacecrew against adverse health effects and performance decrements that would interfere with mission objectives. Because of the 1 and 24 hr SMACs are set for contingencies, minor reversible toxic effects that do not affect mission objectives are acceptable. The 7, 30, or 180 day SMACs are aimed at nominal operations, so they are established at levels that would not cause noncarcinogenic toxic effects and more than one case of tumor per 1000 exposed individuals over the background. The process used to set the SMACs for carbon monoxide (CO) is described to illustrate the approach used by NASA. After the toxicological literature on CO was reviewed, the data were summarized and separated into acute, subchronic, and chronic toxicity data. CO's toxicity depends on the formation of carboxyhemoglobin (COHb) in the blood, reducing the blood's oxygen carrying capacity. The initial task was to estimate the COHb levels that would not produce toxic effects in the brain and heart.

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

    SciTech Connect

    Levesque, B.; Dewailly, E.; Lavoie, R.; Prud'Homme, D.; Allaire, S. )

    1990-05-01

    We evaluated alveolar carbon monoxide (CO) levels of 122 male, adult hockey players active in recreational leagues of the Quebec City region (Canada), before and after 10 weekly 90-minute games in 10 different rinks. We also determined exposure by quantifying the average CO level in the rink during the games. Other variables documented included age, pulmonary function, aerobic capacity, and smoking status. Environmental concentrations varied from 1.6 to 131.5 parts per million (ppm). We examined the absorption/exposure relationship using a simple linear regression model. In low CO exposure levels, physical exercise lowered the alveolar CO concentration. However, we noted that for each 10 ppm of CO in the ambient air, the players had adsorbed enough CO to raise their carboxyhemoglobin (COHb) levels by 1 percent. This relationship was true both for smokers and non-smokers. We suggest that an average environmental concentration of 20 ppm of CO for the duration of a hockey game (90 minutes) should be reference limit not to be exceeded in indoor skating rinks.

  3. TERRA/MOPITT Measurements of Tropospheric Carbon Monoxide Distributions in Support of INTEX

    NASA Technical Reports Server (NTRS)

    Edwards, D. P.; Gille, J. C.; Emmons, L. K.; Ziskin, D.

    2005-01-01

    Interaction with the ongoing satellite measurements programs was an important goal of INTEX- A. The Terra/MOPITT instrument had been making global measurements of the tropospheric carbon monoxide (CO) distribution for 4 years, and was in a unique position to provide valuable support during the field campaign. Remote sensing of CO directly addressed the scientific questions motivating the IXTEX-A strategy and deployment, and measurement of this gas was rated as being mission critical. CO is an important trace gas in tropospheric chemistry due to its role in determining the atmospheric oxidizing capacity, as an ozone precursor, and as an indicator and tracer of both natural and anthropogenic pollution arising from incomplete combustion. The satellite perspective provided the more general temporal and spatial context to the aircraft and ground-based measurements during the subsequent scientific analysis. We proposed to build on the experience of supplying MOPITT data to previous field campaigns, such as TRACE-P. We provided expedited MOPITT data processing in near real-time, along with basic analysis of the measurements to indicate, where possible, the origin of the CO plumes that impacted the regions of flight operations and other in situ measurement activities. To ensure maximum exploitation of the satellite information, we will also had a scientist in the field to present and interpret the MOPITT data for the INTEX team, and to help ensure its utility in flight planning.

  4. Bromine monoxide / sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006-2009

    NASA Astrophysics Data System (ADS)

    Bobrowski, N.; Giuffrida, G.

    2012-12-01

    Over a 3-yr period, from 2006 to 2009, frequent scattered sunlight DOAS measurements were conducted at Mt. Etna at a distance of around 6 km downwind from the summit craters. During the same period and in addition to these measurements, volcanic observations were made by regularly visiting various parts of Mt. Etna. Here, results from these measurements and observations are presented and their relation is discussed. The focus of the investigation is the bromine monoxide/sulphur dioxide (BrO / SO2) ratio, and its variability in relation to volcanic processes. That the halogen/sulphur ratio can serve as a precursor or indicator for the onset of eruptive activity was already proposed by earlier works (e.g. Noguchi and Kamiya 1963; Menyailov, 1975; Pennisi and Cloarec, 1998; Aiuppa et al., 2002). However, there is still a limited understanding today because of the complexity with which halogens are released, depending on magma composition and degassing conditions. Our understanding of these processes is far from complete, for example of the rate and mechanism of bubble nucleation, growth and ascent in silicate melts (Carroll and Holloway, 1994), the halogen vapour-melt partitioning and the volatile diffusivity in the melt (Aiuppa et al., 2009). With this study we aim to add one more piece to the puzzle of what halogen/sulphur ratios might tell about volcanic activities. Our data set shows an increase of the BrO / SO2 ratio several weeks prior to an eruption, followed by a decline before and during the initial phase of eruptive activities. Towards the end of activity or shortly thereafter, the ratio increases to baseline values again and remains more or less constant during quiet phases. To explain the observed evolution of the BrO / SO2 ratio, a first empirical model is proposed. This model suggests that bromine, unlike chlorine and fluorine, is less soluble in the magmatic melt than sulphur. By using the DOAS method to determine SO2, we actually observe most of the

  5. Carbon Monoxide Poisoning In Children: Diagnosis And Management In The Emergency Department.

    PubMed

    Macnow, Theodore E; Waltzman, Mark L

    2016-09-01

    Approximately 5000 children present to the emergency department annually with unintentional carbon monoxide poisoning. Children may be more vulnerable to carbon monoxide poisoning because of their increased metabolic demand and their inability to vocalize symptoms or recognize a dangerous exposure, and newborn infants are more vulnerable to carbon monoxide poisoning because of the persistence of fetal hemoglobin. Mild carbon monoxide poisoning may present as viral symptoms in the absence of fever. While headache, nausea, and vomiting are the most common presenting symptoms in children, the most common symptom in infants is consciousness disturbance. This review discusses the limitations of routine pulse oximetry and carboxyhemoglobin measurement in determining carbon monoxide exposure, and notes effects of co-ingestions and comorbidities. Although the mainstay of treatment is 100% oxygen, the current evidence and controversies in the use of hyperbaric oxygen therapy in pediatric patients is reviewed, along with its possible benefit in preventing delayed neurologic sequelae. PMID:27547917

  6. Minimal risk of carbon monoxide exposure with oil heat: Part I

    SciTech Connect

    Batey, J.E.

    1995-04-01

    What is carbon monoxide? Carbon monoxide (CO) is an odorless, colorless, and tasteless gas that can be produced by all heating equipment used in homes that burn natural gas, propane, fueloil, wood, coal or other home heating fuels. Carbon monoxide is extremely hazardous even in very small concentrations and can produce injury or death when it reaches only a fraction of one percent in the air. The recent reports of injury and death by exposure to carbon monoxide have alerted homeowners to the serious nature of exposure to this gaseous byproduct of fuel burning. The U.S. Environmental Protection Agency (USEPA) has set 9 parts per million carbon monoxide are shown as its concentration in air increases. CO replaces the oxygen in blood and causes hypoxia (lack of oxygen) which can damage the body`s circulatory and central nervous systems leading to injury or death depending on the time of exposure and CO concentration.

  7. Carbon Monoxide Poisoning In Children: Diagnosis And Management In The Emergency Department.

    PubMed

    Macnow, Theodore E; Waltzman, Mark L

    2016-09-01

    Approximately 5000 children present to the emergency department annually with unintentional carbon monoxide poisoning. Children may be more vulnerable to carbon monoxide poisoning because of their increased metabolic demand and their inability to vocalize symptoms or recognize a dangerous exposure, and newborn infants are more vulnerable to carbon monoxide poisoning because of the persistence of fetal hemoglobin. Mild carbon monoxide poisoning may present as viral symptoms in the absence of fever. While headache, nausea, and vomiting are the most common presenting symptoms in children, the most common symptom in infants is consciousness disturbance. This review discusses the limitations of routine pulse oximetry and carboxyhemoglobin measurement in determining carbon monoxide exposure, and notes effects of co-ingestions and comorbidities. Although the mainstay of treatment is 100% oxygen, the current evidence and controversies in the use of hyperbaric oxygen therapy in pediatric patients is reviewed, along with its possible benefit in preventing delayed neurologic sequelae.

  8. A case of carbon monoxide poisoning with thrombus in the heart: a case report.

    PubMed

    Yildirim, Cuma; Günay, Nurullah; Büyükaslan, Hasan; Küçükdurmaz, Zekeriya; Bozkurt, Selim

    2005-12-15

    Carbon monoxide is a nonirritant, odorless, colorless gas, and is lighter than air. It is an end product of the incomplete combustion of hydrocarbons. Its effects are most prominent in organs sensitive to oxygen deprivation, such as the heart, brain, and kidney. Carbon monoxide poisoning becomes more abundant in winter and at cold places. In Turkey, every year we see several deaths due to poisonous gas leaks from coal or wood stoves. Deaths particularly due to hypoxia-related central nervous system damage and ventricular dysrhythmias are observed. On the other hand, an association between thromboembolic accidents and carbon monoxide poisoning has been shown in literature. Thromboembolic accidents in the mesenteric, central nervous system, and extremities are reported. However, no atrial thrombus has been mentioned. In this study, a case of an atrial thrombus associated with carbon monoxide poisoning following a diagnosis of carbon monoxide poisoning and treatment in the emergency room is reported and the literature is revisited. PMID:16282157

  9. Analysis of offshore atmospheric diffusion characteristics

    SciTech Connect

    Hiraga, Kunio; Omoto, Akira; Takahashi, Keiichi; Momoi, Kazuyoshi

    1994-12-31

    Although almost all of the thermal and nuclear power stations in Japan are located on the coastline to take advantage of seawater available to condense steam, offshore siting is one of the candidates for the future plant sitting. Figures developed by Pasquill-Gifford model has been conventionally utilized in analyzing atmospheric diffusion of gaseous effluent from power plants. However, there are limitations to apply this to offshore plants because these figures are based on inland diffusion experiments and this model does not specifically take into consideration the effects of thermal capacity of seawater, its surface roughness and so on. Even in the case of coastline sitting, atmospheric diffusion of gaseous effluent might be affected by atmospheric diffusion characteristics above seawater. With this background gaseous, diffusion experiments were conducted at one of TEPCo`s (Tokyo Electric Power Company) coastline power station and empirical formula to model atmospheric diffusion above seawater has been developed.

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

    SciTech Connect

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

    1992-09-01

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

  11. 40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Oxides of nitrogen, carbon monoxide....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...

  12. 40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Oxides of nitrogen, carbon monoxide....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...

  13. 40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Oxides of nitrogen, carbon monoxide....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...

  14. 40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Oxides of nitrogen, carbon monoxide....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...

  15. 40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Oxides of nitrogen, carbon monoxide....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...

  16. 40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

    Code of Federal Regulations, 2010 CFR

    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...

  17. 40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

  18. 40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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...

  19. 40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 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...

  20. 40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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...

  1. Can carbon monoxide-poisoned victims be organ donors?

    PubMed

    Fujisaki, Noritomo; Nakao, Atsunori; Osako, Takaaki; Nishimura, Takeshi; Yamada, Taihei; Kohama, Keisuke; Sakata, Hiroyuki; Ishikawa-Aoyama, Michiko; Kotani, Joji

    2014-01-01

    The increasing demand for organ allografts to treat end-stage organ failure has driven changes in traditional donor criteria. Patients who have succumbed to carbon monoxide (CO) poisoning, a common cause of toxicological mortality, are usually rejected as organ donors. To fulfill the increasing demand, selection criteria must be expanded to include CO-poisoned donors. However, the use of allografts exposed to high CO concentrations is still under debate. Basic research and literature review data suggest that patients with brain death caused by CO poisoning should be considered appropriate organ donors. Accepting organs from CO-poisoned victims could increase the number of potential donors and lower the death rate of patients on the waiting lists. This review and reported cases may increase awareness among emergency department physicians, as well as transplant teams, that patients dying of CO exposure may be acceptable organ donors.

  2. Size Effect of Ruthenium Nanoparticles in Catalytic Carbon Monoxide Oxidation

    SciTech Connect

    Joo, Sang Hoon; Park, Jeong Y.; Renzas, J. Russell; Butcher, Derek R.; Huang, Wenyu; Somorjai, Gabor A.

    2010-04-04

    Carbon monoxide oxidation over ruthenium catalysts has shown an unusual catalytic behavior. Here we report a particle size effect on CO oxidation over Ru nanoparticle (NP) catalysts. Uniform Ru NPs with a tunable particle size from 2 to 6 nm were synthesized by a polyol reduction of Ru(acac){sub 3} precursor in the presence of poly(vinylpyrrolidone) stabilizer. The measurement of catalytic activity of CO oxidation over two-dimensional Ru NPs arrays under oxidizing reaction conditions (40 Torr CO and 100 Torr O{sub 2}) showed an activity dependence on the Ru NP size. The CO oxidation activity increases with NP size, and the 6 nm Ru NP catalyst shows 8-fold higher activity than the 2 nm catalysts. The results gained from this study will provide the scientific basis for future design of Ru-based oxidation catalysts.

  3. Reduction of carbon monoxide emissions with regenerative thermal oxidizers

    SciTech Connect

    Firmin, S.M.; Lipke, S.; Baturay, A.

    1996-09-01

    Regenerative thermal oxidizers (RTOs) have been extensively used for the control of volatile organic compound (VOC) emissions from various sources. However, very little information is available on the ability of RTOs to control carbon monoxide (CO) emissions. This paper presents the results of extensive tests conducted on two RTOs to determine their VOC and CO control efficiencies. The inlet gas stream to the RTOs includes VOC and CO concentrations as high as 2,000 ppm and 3,600 ppm, respectfully. The testing demonstrated that both RTOs were capable of controlling greater than 98% of both inlet VOCs and CO. While the destruction efficiencies within the combustion chambers exceeded 99.9%, direct leakage past valves accounted for the lower control efficiencies. The tests indicated that the overall VOC and CO control efficiencies of the RTOs may be limited by valve leakage. The design and permitting of a RTO should include conservative control estimates which account for possible valve leakage.

  4. Detection of Carbon Monoxide Using Polymer-Carbon Composite Films

    NASA Technical Reports Server (NTRS)

    Homer, Margie L.; Ryan, Margaret A.; Lara, Liana M.

    2011-01-01

    A carbon monoxide (CO) sensor was developed that can be incorporated into an existing sensing array architecture. The CO sensor is a low-power chemiresistor that operates at room temperature, and the sensor fabrication techniques are compatible with ceramic substrates. Sensors made from four different polymers were tested: poly (4-vinylpryridine), ethylene-propylene-diene-terpolymer, polyepichlorohydrin, and polyethylene oxide (PEO). The carbon black used for the composite films was Black Pearls 2000, a furnace black made by the Cabot Corporation. Polymers and carbon black were used as received. In fact, only two of these sensors showed a good response to CO. The poly (4-vinylpryridine) sensor is noisy, but it does respond to the CO above 200 ppm. The polyepichlorohydrin sensor is less noisy and shows good response down to 100 ppm.

  5. The dissociation of shock-heated carbon monoxide

    NASA Technical Reports Server (NTRS)

    Hanson, R. K.

    1973-01-01

    Investigation of the dissociation kinetics of undiluted carbon monoxide over the 5,600 to 12,000 K temperature range. Data are presented that have been obtained as time-resolved pressure measurements on the end wall of a shock tube and radiation emission of a C2 Swan system (0-0 band) behind incident shock waves. The decomposition of CO is complex and includes a chain with C2 as an intermediate species. The dissociation rate for the overall process has been found to be independent of the proportions of the collision partners M = CO, C, and O. The rate constant found is on the average about 10 times that previously measured with argon as the collision partner.

  6. Carbon Monoxide as a Signaling Molecule in Plants

    PubMed Central

    Wang, Meng; Liao, Weibiao

    2016-01-01

    Carbon monoxide (CO), a gaseous molecule, has emerged as a signaling molecule in plants, due to its ability to trigger a series of physiological reactions. This article provides a brief update on the synthesis of CO, its physiological functions in plant growth and development, as well as its roles in abiotic stress tolerance such as drought, salt, ultraviolet radiation, and heavy metal stress. CO has positive effects on seed germination, root development, and stomatal closure. Also, CO can enhance plant abiotic stress resistance commonly through the enhancement of antioxidant defense system. Moreover, CO shows cross talk with other signaling molecules including NO, phytohormones (IAA, ABA, and GA) and other gas signaling molecules (H2S, H2, CH4). PMID:27200045

  7. Carbon Monoxide as a Signaling Molecule in Plants.

    PubMed

    Wang, Meng; Liao, Weibiao

    2016-01-01

    Carbon monoxide (CO), a gaseous molecule, has emerged as a signaling molecule in plants, due to its ability to trigger a series of physiological reactions. This article provides a brief update on the synthesis of CO, its physiological functions in plant growth and development, as well as its roles in abiotic stress tolerance such as drought, salt, ultraviolet radiation, and heavy metal stress. CO has positive effects on seed germination, root development, and stomatal closure. Also, CO can enhance plant abiotic stress resistance commonly through the enhancement of antioxidant defense system. Moreover, CO shows cross talk with other signaling molecules including NO, phytohormones (IAA, ABA, and GA) and other gas signaling molecules (H2S, H2, CH4). PMID:27200045

  8. Detection of the J = 6. -->. 5 transition of carbon monoxide

    SciTech Connect

    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.

    1981-01-15

    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/sup -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.

  9. The effect of carbon monoxide on planetary haze formation

    SciTech Connect

    Hörst, S. M.; Tolbert, M. A

    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.

  10. A divalent rare earth oxide semiconductor: Yttrium monoxide

    NASA Astrophysics Data System (ADS)

    Kaminaga, Kenichi; Sei, Ryosuke; Hayashi, Kouichi; Happo, Naohisa; Tajiri, Hiroo; Oka, Daichi; Fukumura, Tomoteru; Hasegawa, Tetsuya

    2016-03-01

    Rare earth oxides are usually widegap insulators like Y2O3 with closed shell trivalent rare earth ions. In this study, solid phase rock salt structure yttrium monoxide, YO, with unusual valence of Y2+ (4d1) was synthesized in a form of epitaxial thin film by pulsed laser deposition method. YO has been recognized as gaseous phase in previous studies. In contrast with Y2O3, YO was dark-brown colored and narrow gap semiconductor. The tunable electrical conductivity ranging from 10-1 to 103 Ω-1 cm-1 was attributed to the presence of oxygen vacancies serving as electron donor. Weak antilocalization behavior observed in magnetoresistance indicated significant role of spin-orbit coupling as a manifestation of 4d electron carrier.

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

    PubMed

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

    2012-01-01

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

  12. Carbon Monoxide Expedites Metabolic Exhaustion to Inhibit Tumor Growth

    PubMed Central

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

    2013-01-01

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

  13. The therapeutic potential of carbon monoxide for inflammatory bowel disease.

    PubMed

    Takagi, Tomohisa; Uchiyama, Kazuhiko; Naito, Yuji

    2015-01-01

    Inflammatory bowel disease (IBD), encompassing ulcerative colitis and Crohn's disease, are chronic, relapsing and remitting inflammatory disorders of the intestinal tract. Because the precise pathogenesis of IBD remains unclear, it is important to investigate the pathogenesis of IBD and to evaluate new anti-inflammatory strategies. Recent accumulating evidence has suggested that carbon monoxide (CO) may act as an endogenous defensive gaseous molecule to reduce inflammation and tissue injury in various organ injury models, including intestinal inflammation. Furthermore, exogenous CO administration at low concentrations is protective against intestinal inflammation. These data suggest that CO may be a novel therapeutic molecule in patients with IBD. In this review, we present what is currently known regarding the therapeutic potential of CO in intestinal inflammation.

  14. Anesthesia-Related Carbon Monoxide Exposure: Toxicity and Potential Therapy.

    PubMed

    Levy, Richard J

    2016-09-01

    Exposure to carbon monoxide (CO) during general anesthesia can result from volatile anesthetic degradation by carbon dioxide absorbents and rebreathing of endogenously produced CO. Although adherence to the Anesthesia Patient Safety Foundation guidelines reduces the risk of CO poisoning, patients may still experience subtoxic CO exposure during low-flow anesthesia. The consequences of such exposures are relatively unknown. In contrast to the widely recognized toxicity of high CO concentrations, the biologic activity of low concentration CO has recently been shown to be cytoprotective. As such, low-dose CO is being explored as a novel treatment for a variety of different diseases. Here, we review the concept of anesthesia-related CO exposure, identify the sources of production, detail the mechanisms of overt CO toxicity, highlight the cellular effects of low-dose CO, and discuss the potential therapeutic role for CO as part of routine anesthetic management. PMID:27537758

  15. Exchange coupling in transition metal monoxides: Electronic structure calculations

    SciTech Connect

    Fischer, Guntram; Daene, Markus W; Ernst, Arthur; Bruno, Patrick; Lueders, Martin; Szotek, Zdzislawa; Temmerman, Walter M; Wolfam, Hergert

    2009-01-01

    An ab initio study of magnetic-exchange interactions in antiferromagnetic and strongly correlated 3d transition metal monoxides is presented. Their electronic structure is calculated using the local self-interaction correction approach, implemented within the Korringa-Kohn-Rostoker band-structure method, which is based on multiple scattering theory. The Heisenberg exchange constants are evaluated with the magnetic force theorem. Based on these the corresponding Neel temperatures TN and spin-wave dispersions are calculated. The Neel temperatures are obtained using mean-field approximation, random-phase approximation and Monte Carlo simulations. The pressure dependence of TN is investigated using exchange constants calculated for different lattice constants. All the calculated results are compared to experimental data.

  16. UV-induced carbon monoxide emission from living vegetation

    NASA Astrophysics Data System (ADS)

    Bruhn, D.; Albert, K. R.; Mikkelsen, T. N.; Ambus, P.

    2013-12-01

    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 a chamber on a field of grass or a plant-leaf scale chamber. Leaves of all plant species that were examined 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 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 natural grassland scale.

  17. Catalytic removal of carbon monoxide over carbon supported palladium catalyst.

    PubMed

    Srivastava, Avanish Kumar; Saxena, Amit; Shah, Dilip; Mahato, T H; Singh, Beer; Shrivastava, A R; Gutch, P K; Shinde, C P

    2012-11-30

    Carbon supported palladium (Pd/C) catalyst was prepared by impregnation of palladium chloride using incipient wetness technique, which was followed by liquid phase reduction with formaldehyde. Thereafter, Pd/C catalyst was characterized using X-ray diffractometery, scanning electron microscopy, atomic absorption spectroscopy, thermo gravimetry, differential scanning calorimetry and surface characterization techniques. Catalytic removal of carbon monoxide (CO) over Pd/C catalyst was studied under dynamic conditions. Pd/C catalyst was found to be continuously converting CO to CO(2) through the catalyzed reaction, i.e., CO+1/2O(2)→CO(2). Pd/C catalyst provided excellent protection against CO. Effects of palladium wt%, CO concentration, humidity, space velocity and reaction environment were also studied on the breakthrough behavior of CO. PMID:23083941

  18. [Etiology of combined inhalational hydrocyanic acid and carbon monoxide poisoning].

    PubMed

    Sigrist, T; Dirnhofer, R

    1979-01-01

    A young man was found dead in a kitchen, that was partly burnt. Autopsy revealed, as cause of death, a combined intoxication following inhalation of carbon monoxide and hydrocyanic acid. Own investigations on the pyrolysis of pieces of furniture found in the kitchen (plastic plates containing melamine and plates containing formaldehyde) showed, that hydrocyanic acid was liberated through combustion of such substances and inhaled by the victim. The poisoning picture is discussed, and discussion includes especially considerations on the peculiar sensitivity of the brain toward the action of hydrocyanic acid and the relative insensitivity of the heart muscle. It is thought that the cause of such sensitivity difference lies in the physiological differences of the intracellular energy production. Finally the dangers of combustion gases developing from burning plastic materials are reemphasized.

  19. Multiple targets of carbon monoxide gas in the intestinal inflammation.

    PubMed

    Naito, Yuji; Takagi, Tomohisa; Uchiyama, Kazuhiko; Katada, Kazuhiro; Yoshikawa, Toshikazu

    2016-04-01

    Inflammatory bowel diseases (IBDs) such as ulcerative colitis and Crohn's disease are chronic relapsing and remitting inflammatory disorders of the intestinal tract. It is important to investigate the precise pathogenesis of IBD, to evaluate new anti-inflammatory agents, and to develop novel drugs. Carbon monoxide (CO) has emerged as an important regulator of acute and chronic inflammation of the gastrointestinal tract. The mechanism underlying its anti-inflammatory effects is only partially understood. Recent reports have demonstrated that CO could play a role in the functional modulation of epithelial and immunological cells in the intestine. In this short review, we have highlighted the recent findings that CO stimulates the epithelial cell restitution and FGF production from myofibroblasts. CO was also shown to regulate T cell activation and differentiation, and to activate macrophages. Finally, we have discussed the direction of translational research with respect to launching a novel agent for releasing CO in the intestine.

  20. A possible carbon monoxide shuttle in the lung.

    PubMed

    Coburn, Ronald F

    2016-08-01

    The Coburn, Forster, Kane Equation (CFKE) describes a current understanding of the physiology of lung uptake and excretion of carbon monoxide (CO). The lung mean capillary PCO is an important term in this equation because it drives CO excretion and functions as "back-pressure" during uptake of exogenous CO. Results of previous studies have indicated that the mean capillary PCO of normal human lungs is equal to values calculated using the Haldane Equation, as described by the CFKE. The physiological explanation of how this parameter is set at this level is unknown. As a possible explanation, this study tested a hypothesis that a CO shuttle could be involved. Results of calculation-simulations indicate that a CO shuttle operates in a single alveolus model and imply that it could function as a determinant of the lung mean capillary PCO.