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Sample records for monoxide diffusing capacity

  1. 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.

  2. Can the measurement of pulmonary diffusing capacity for nitric oxide replace the measurement of pulmonary diffusing capacity for carbon monoxide?

    PubMed

    Zavorsky, Gerald S; van der Lee, Ivo

    2016-11-21

    Pulmonary diffusing capacity for carbon monoxide (DLCO) has been an important pulmonary function test used since the 1950's. It measures the uptake of CO from the alveolar space into pulmonary capillary blood, following the same path as oxygen. It's used to evaluate/follow the progress of various lung diseases. In the eighties, a new test was developed similar to the DLCO test: pulmonary diffusing capacity for nitric oxide (DLNO). About 81-90% of the variance in DLNO is shared by DLCO in patients with cardiopulmonary disease and in healthy subjects. When DLNO is abnormally low, so is DLCO, and when DLNO is normal, so is DLCO (Kappa Statistic=0.69, n=251). The probability that DLNO and DLCO will be abnormally low when a cardiopulmonary disease is present (sensitivity) is 79% and 68%, respectively. The DLNO test avoids many technical issues associated with the measurement of DLCO: (1) DLNO is relatively unaffected by inspired oxygen concentration or ambient pressure, (2) DLNO is unaffected by carboxyhemoglobin, (3) DLNO is minimally affected by hemoglobin (Hb) concentration, thus correcting for Hb is not needed. (4) DLNO is more affected by lung volume compared to DLCO, thus DLNO divided by alveolar volume (KNO) is a better measure than KCO in those with restrictive lung disease, and (5) DLNO is a more stable measure over time compared to DLCO. Therefore, DLNO has several advantages over DLCO in the management of patients and could replace the DLCO test in most cases moving forward.

  3. Effects of increasing carboxyhemoglobin on the single breath carbon monoxide diffusing capacity.

    PubMed

    Graham, Brian L; Mink, Joseph T; Cotton, David J

    2002-06-01

    Although carboxyhemoglobin (COHb) is often increased in smokers, American Thoracic Society recommendations for adjusting the single breath carbon monoxide (CO) diffusing capacity (DL(CO)(SB)) for COHb remain optional. Using a previously described 3-equation technique, we measured DL(CO)(SB) and an index of diffusion inhomogeneity (DI) in 10 healthy, nonsmoking subjects who performed DL(CO)(SB) maneuvers both before and after increasing COHb. CO backpressure (FA(CO)) was measured from the exhaled gas of a standardized deep breath of room air that immediately preceded each DL(CO)(SB) and was validated by measurement of FA(CO) from an identical "sham" maneuver without inhaling CO. Without adjustments for FA(CO) or COHb, DL(CO)(SB) decreased with increasing COHb. This effect persisted when DL(CO)(SB) was adjusted only for FA(CO), but it was eliminated with further adjustment for the anemia effect of increasing COHb. The anemia adjustment was proportional to the fractional COHb. DI, adjusted for FA(CO), was unaffected by increasing COHb. We conclude that DL(CO)(SB) must be adjusted for both the buildup of CO backpressure and the anemia effect of increasing COHb. Adequate corrections of DL(CO)(SB) can be implemented using FA(CO) measured during a standardized deep breath immediately preceding the DL(CO)(SB) maneuver. Current American Thoracic Society recommendations for DL(CO)(SB) standardization do not adequately compensate for COHb.

  4. 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

  5. Rest and exercise cardiac output and diffusing capacity assessed by a single slow exhalation of methane, acetylene, and carbon monoxide.

    PubMed

    Ramage, J E; Coleman, R E; MacIntyre, N R

    1987-07-01

    To study rest and exercise pulmonary capillary blood flow (Qc) and diffusing capacity (DLexh) assessed by the rapid analysis of methane, acetylene, and carbon monoxide during a single, slow exhalation, we evaluated 36 subjects during first-pass radionuclide angiography (RNA). At rest (N = 36) and at exercise (N = 21) there was no difference in the respective measurements of cardiac output (Qc = 6.0 +/- 1.7 and CORNA = 6.9 +/- 2.5 at rest; Qc = 13.7 +/- 3.2 and CORNA = 14.5 +/- 4.1 at exercise, L/min, mean +/- SD, r = .80). Mild maldistribution of ventilation, as manifested by an increased phase 3 alveolar slope for methane (CH4 slope), did not significantly influence the results. CH4 slope and DLexh did increase significantly with exercise, while total lung capacity remained unchanged (CH4 slope: 6.2 +/- 5.0 vs 12.5 +/- 6.8% delta CH4/L, mean +/- SD, p less than 0.001; Dsb: 27.7 +/- 9.2 vs 42.0 +/- 17.9 ml/min/mm Hg, mean +/- SD, p less than 0.001; TLC: 5.47 +/- .20 vs 5.96 +/- 1.20 L, mean +/- SD). DLexh was related to CORNA (r = .68) and RNA stroke volume (r = .50). Qc was significantly less than CORNA in the subset of studies with valvular regurgitation (VHD) (N = 7). On the other hand, Qc was significantly greater than CORNA in the setting of coronary artery disease (CAD) and severe wall motion abnormalities (N = 7). These differences may be attributed to regurgitant fractions in VHD, and the influence of wall motion abnormalities on the estimation of left ventricular volume by the area-length method in CAD. These two noninvasive methods compare well at rest and exercise in clinical subjects and may provide complementary information in certain cardiopulmonary diseases.

  6. Single breath diffusing capacity for carbon monoxide: effects of adjustment for inspired volume dead space, carbon dioxide, hemoglobin and carboxyhemoglobin.

    PubMed

    Viegi, G; Baldi, S; Begliomini, E; Ferdeghini, E M; Pistelli, F

    1998-01-01

    In order to assess the additive effects of taking into account dead space volume (VD), carbon dioxide, hemoglobin (Hb) and carboxyhemoglobin on computation of single breath carbon monoxide diffusing capacity (DLCOsb), we sequentially applied all the corrections recommended by the 1987 American Thoracic Society (ATS) document on DLCOsb standardization. We used data from 739 men (333 nonsmokers and 406 current smokers) and 475 women (403 nonsmokers and 72 current smokers) who underwent measurement of DLCOsb in the decade 1985-1994 at the Lung Function Laboratory of our institute. With respect to the unadjusted DLCOsb value, significant small differences were found for all the corrected formulas, ranging from -0.18 to 1.48 ml/min/mm Hg in men and from -0.24 to 1.57 ml/min/mm Hg in women. After computing the percent change of DLCOsb [(unadjusted-adjusted value) x 100/unadjusted value], we observed that the correction for VD caused an underestimation of DLCOsb of about 5.8% in men and 7.7% in women. However, when all the corrections were considered, these figures decreased to about 0.9% in males and 2.9% in females. Regarding specifically the correction for Hb, the adjusted value was slightly lower in men, while it was some-what higher in women, with respect to the unadjusted DLCOsb. In conclusion, the corrections suggested by ATS in the computation of DLCOsb, when considered altogether, seem to account for a limited proportion of test variability in usual clinical conditions, especially in males.

  7. Short-term effect of cold provocation on single-breath carbon monoxide diffusing capacity in subjects with and without Raynaud's phenomenon.

    PubMed

    Gastaud, M; Dolisi, C; Bermon, S; Gaudin, P; Defauw, G; Ardisson, J L

    1995-01-01

    The lung diffusing capacity for carbon monoxide was determined by the single breath method (DLCOsb) before, during, and after immersion of the left hand in cold water in four groups of subjects: (i) normal individuals; (ii) subjects with idiopathic Raynaud's disease; (iii) patients with progressive systemic sclerosis without associated Raynaud's phenomenon; and (iv) patients with connective tissue disease associated with Raynaud's phenomenon. Our results showed significant differences in the evolution of DLCOsb after cold stimulation between the groups. Control subjects (group one) showed a transient but significant reduction in DLCOsb at the end of two minutes of cold stimulation, normalizing ten minutes later. Subjects with primary Raynaud's phenomenon (group two) showed on the contrary a transient but significant rise in DLCOsb after 2 minutes, while subjects with an isolated connective tissue disease without Raynaud's phenomenon (group three) showed a significant decrease in DLCOsb at both observation times. Patients with Raynaud's phenomenon associated with a connective tissue disease (group four) showed a delayed decrease in DLCOsb ten minutes after cold stimulation. This latter result appeared as an addition to the effects of cold stimulation observed in groups two and three.

  8. Reference values for pulmonary diffusing capacity for adult native Finns.

    PubMed

    Kainu, Annette; Toikka, Jyri; Vanninen, Esko; Timonen, Kirsi L

    2017-04-01

    Measurement standards for pulmonary diffusing capacity were updated in 2005 by the ATS/ERS Task Force. However, in Finland reference values published in 1982 by Viljanen et al. have been used to date. The main aim of this study was to produce updated reference models for single-breath diffusing capacity for carbon monoxide for Finnish adults. Single-breath diffusing capacity for carbon monoxide was measured in 631 healthy non-smoking volunteers (41.5% male). Reference values for diffusing capacity (DLCO), alveolar volume (VA), diffusing capacity per unit of lung volume (DLCO/VA), and lung volumes were calculated using a linear regression model. Previously used Finnish reference values were found to produce too low predicted values, with mean predicted DLCO 111.0 and 104.4%, and DLCO/VA of 103.5 and 102.7% in males and females, respectively. With the European Coalition for Steel and Coal (ECSC) reference values there was a significant sex difference in DLCO/VA with mean predicted 105.4% in males and 92.8% in females (p < .001). New reference values for DLCO, DLCO/VA, VA, vital capacity (VC), inspiratory vital capacity (IVC), and inspiratory capacity (IC) are suggested for clinical use to replace technically outdated reference values for clinical applications.

  9. 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.

  10. Regional diffusing capacity in normal lungs during a slow exhalation.

    PubMed

    MacIntyre, N R; Nadel, J A

    1982-06-01

    From an analysis of carbon monoxide uptake and xenon-133 distribution after two bolus inhalations of these gases, we calculated regional diffusing capacity in the upper and lower volume halves of the lungs during the middle 60% of an exhaled vital capacity in five seated normal subjects. We found that the regional diffusing capacity of the upper half of the lungs was 11.6 +/- 4.2 (mean +/- SD) ml.min-1.Torr-1 and that the regional diffusing capacity of the lower half of the lungs was 24.4 +/- 2.4 ml.min-1.Torr-1 after 25% of the vital capacity had been exhaled. These values remained relatively constant as lung volume decreased from 25 to 75% of the exhaled vital capacity. Diffusing capacity in the upper half of the lungs ranged from 9.4 to 12.4 ml.min-1.Torr-1 during exhalation, and in the lower half of the lungs from 21.0 to 28.6 ml.min-1.Torr-1 during exhalation. These results suggest that total lung diffusing capacity remains relatively constant over this midrange of lung volumes and that this occurs because the regional diffusing capacities in both the upper and lower halves of the lungs remain relatively constant.

  11. 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)

  12. 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.

  13. 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)

  14. Molecular simulation of diffusion of hydrogen, carbon monoxide, and water in heavy n-alkanes.

    PubMed

    Makrodimitri, Zoi A; Unruh, Dominik J M; Economou, Ioannis G

    2011-02-17

    The self-diffusion and mutual diffusion coefficients of hydrogen (H(2)), carbon monoxide (CO), and water (H(2)O) in n-alkanes were studied by molecular dynamics simulation. n-Alkane molecules were modeled based on the TraPPE united atom force field. NPT molecular dynamics (MD) simulations were performed for n-C(12) to n-C(96) at different temperature and pressure values to validate the accuracy of the force field. In all cases, good agreement was obtained between literature experimental data and model predictions for the density and structure properties of the n-alkanes. Subsequently, the self-diffusion coefficient of the three light components in the various n-alkanes was calculated at different temperatures. Model predictions were in very good agreement with limited experimental data. Furthermore, the Maxwell-Stefan diffusion coefficients of H(2) and CO in two n-alkanes, namely n-C(12) and n-C(28), were calculated based on long MD NVT simulations for different solute concentrations in the n-alkanes. Finally, the Fick diffusion coefficient of the components was calculated as a product of the Maxwell-Stefan diffusion coefficient and a thermodynamic factor. The latter was estimated from the statistical associating fluid theory (SAFT). The Fick diffusion coefficient was found to be higher than the Maxwell-Stefan diffusion coefficient for H(2) and CO in n-C(28). The empirical Darken equation was used to estimate the Maxwell-Stefan diffusion coefficient, and calculations were found to be in good agreement with simulation results.

  15. Longitudinal study of carbon monoxide intoxication by diffusion tensor imaging with neurospsychiatric correlation

    PubMed Central

    Chang, Chiung-Chih; Chang, Wen-Neng; Lui, Chun-Chung; Wang, Jiun-Jie; Chen, Chih-Feng; Lee, Yu-Chang; Chen, Shun-Sheng; Lin, Yu-Ting; Huang, Chi-Wei; Chen, Ching

    2010-01-01

    Background White matter damage is common after carbon monoxide (CO) intoxication, but in vivo follow-up studies about the mechanism of white matter damage are not possible in pathology series. Diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) can quantify diffusion parameters and volumetric changes in white matter that can be correlated with neuropsychological performances in longitudinal studies. Methods We examined 9 patients with CO intoxication using DTI, VBM and neuropsychologic tests at an average of 3 and 10 months after CO exposure. We used data from 18 age- and sex-matched controls for comparison. Results We found that cognitive recovery at 10 months after CO intoxication was not significant, although it was after 3 months. The neuropsychologic tests correlated better for the fibre tract of the semicentrum ovale and not the periventricular fibres. Diffusion measures suggest increases in fractional anisotropy, mean diffusivity and axial eigenvalues over time, while increases in radial eigenvalue were evident at 3 months compared with controls. Periventricular white matter atrophy was observed 10 months after CO intoxication Limitations Our study included few cases, and the interpretation of the putative changes on neuroimaging findings cannot be confirmed by histology. Conclusion Our study showed that the evolution of white matter injury in CO encephalopathy occurred over time. Cognitive recovery was not evident in the follow-up period because of white matter injuries. PMID:20184809

  16. [Post mortem diffusion of carbon monoxide to muscles and blood--preliminary examinations].

    PubMed

    Teresiński, Grzegorz; Buszewicz, Grzegorz; Madro, Roman

    2004-01-01

    The purpose of the study was to determine whether the postmortem diffusion of carbon monoxide (CO) significantly affected the results of carboxyhemoglobin (COHb) and carboxymyoglobin (COMb) determinations. The musculocutaneous and muscular specimens collected from adult cadavers were used. The specimens were treated with CO for 24 h at room temperature. COHb and COMb were determined using gas chromatography. It was demonstrated that the skin substantially limited the diffusion of CO which slightly penetrated only the superficial layers of the muscle and did not change the blood level of COHb in the 4.5-cm layer of the muscle located underneath. The CO diffusion through the superficially charred and thermally coagulated muscle did not differ from that observed in the intact integuments. On the other hand, the membrane of the skin completely deprived of the adipose layer was not the barrier to moderate diffusion into the blood layer situated below. Thus, in charred corpses the results pf COHb and COMb determinations in the material collected under the layer of charred and coagulated tissues enable us to determine whether the victim was alive at the moment of the outbreak.

  17. Phenotyping mouse pulmonary function in vivo with the lung diffusing capacity.

    PubMed

    Limjunyawong, Nathachit; Fallica, Jonathan; Ramakrishnan, Amritha; Datta, Kausik; Gabrielson, Matthew; Horton, Maureen; Mitzner, Wayne

    2015-01-06

    The mouse is now the primary animal used to model a variety of lung diseases. To study the mechanisms that underlie such pathologies, phenotypic methods are needed that can quantify the pathologic changes. Furthermore, to provide translational relevance to the mouse models, such measurements should be tests that can easily be done in both humans and mice. Unfortunately, in the present literature few phenotypic measurements of lung function have direct application to humans. One exception is the diffusing capacity for carbon monoxide, which is a measurement that is routinely done in humans. In the present report, we describe a means to quickly and simply measure this diffusing capacity in mice. The procedure involves brief lung inflation with tracer gases in an anesthetized mouse, followed by a 1 min gas analysis time. We have tested the ability of this method to detect several lung pathologies, including emphysema, fibrosis, acute lung injury, and influenza and fungal lung infections, as well as monitoring lung maturation in young pups. Results show significant decreases in all the lung pathologies, as well as an increase in the diffusing capacity with lung maturation. This measurement of lung diffusing capacity thus provides a pulmonary function test that has broad application with its ability to detect phenotypic structural changes with most of the existing pathologic lung models.

  18. Diffusion capacity of the lung in young and old endurance athletes.

    PubMed

    Degens, H; Rittweger, J; Parviainen, T; Timonen, K L; Suominen, H; Heinonen, A; Korhonen, M T

    2013-12-01

    Lung diffusion capacity (D LCO) declines with age. A significant proportion of older endurance athletes develop exercise-induced hypoxemia (SaO2<95%). We hypothesised that master endurance athletes have a lower D LCO than age-matched non-athletes. We recruited 33 control (16 young; 17 old) and 29 male endurance athletes (13 young; 16 old) during the World Masters Athletics Indoor Championships, 2012 (Jyväskylä, Finland). To measure D LCO the participant exhaled to residual volume and then quickly inhaled to ≥ 90% total lung capacity from a gas source with 0.3% carbon monoxide. The D LCO and transfer coefficient (K CO) were corrected for the actual haemoglobin concentration. Spirometric function was similar in athletes and age-matched controls. D LCO and K CO were 33% and 25% lower in old and young controls, respectively (P<0.001). Although predicted D LCO and K CO were 11%-points higher in athletes than age-matched controls (P<0.001), they were 23% and 16% lower in old athletes than young controls, respectively (P<0.001). D LCO did not correlate with age-graded performance or weekly training hours. The better lung diffusion capacity in male endurance athletes than age-matched controls might be an adaptation to training, self-selection and/or attrition bias. However, the diffusion capacity of the older athlete is lower than that of the young non-athlete.

  19. 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.

  20. Pulmonary diffusing capacity in healthy African-American and Caucasian children.

    PubMed

    Kim, Young-Jee; Christoph, Kathy; Yu, Zhangsheng; Eigen, Howard; Tepper, Robert S

    2016-01-01

    Previous studies of pulmonary diffusing capacity in healthy children primarily focused upon Caucasian (C) subjects. Since lung volumes in African-Americans (AA) are smaller than lung volumes in C subjects of the same height, diffusing capacity values in AA children might be interpreted as low or abnormal using currently available equations without adjusting for race. Healthy AA (N = 151) and C (N = 301) children between 5 and 18 years of age performed acceptable measurements of single breath pulmonary diffusing capacity for carbon monoxide (DLCO ) and alveolar volume (VA ) according to current ATS/ERS guidelines. The natural log of DLCO and VA were associated with height, gender, age, and race; AA children had lower DLCO and VA compared to C children. Adjustment of DLCO for Hemoglobin (Hgb) resulted in no significant difference in DLCO among these healthy subjects with normal Hgb. In summary, we report prediction equations for DLCO and VA that include adjustment for race (C; AA) demonstrating that AA have lower DLCO and VA compared to C children for the same height, gender, and age.

  1. A rebreathing method for measuring lung volume, diffusing capacity and cardiac output in conscious small animals.

    PubMed

    Yilmaz, Cuneyt; Johnson, Robert L; Hsia, Connie C W

    2005-04-15

    We developed a multiple gas rebreathing technique for measuring lung diffusing capacity (DL(CO)), lung volume (V(L)) and cardiac output simultaneously in conscious spontaneously breathing small animals. Lung volume was measured from the dilution of methane (CH4) or sulfur hexafluoride (SF6) and verified independently by a helium washout technique. Cardiac output and DL(CO) were estimated from the uptake of acetylene and carbon monoxide, respectively. We tested guinea pigs at two levels of alveolar oxygen tension in order to estimate membrane diffusing capacity and pulmonary capillary blood volume by the Roughton-Forster technique. Results show that measured DL(CO) are consistent with reported values in anesthetized guinea pigs as well as with allometric comparison across species. Lung volume estimated from SF6 dilution agreed closely with that estimated independently from helium washout; however, lung volume estimated from CH4 dilution was systematically lower due to the addition of endogenously produced CH4 to the rebreathing system. We conclude that this technique can be used to measure resting lung function in conscious unsedated small animals.

  2. [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.

  3. 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.

  4. Universality of Viscosity Dependence of Translational Diffusion Coefficients of Carbon Monoxide, Diphenylacetylene, and Diphenylcyclopropenone in Ionic Liquids under Various Conditions.

    PubMed

    Kimura, Y; Kida, Y; Matsushita, Y; Yasaka, Y; Ueno, M; Takahashi, K

    2015-06-25

    Translational diffusion coefficients of diphenylcyclopropenone (DPCP), diphenylacetylene (DPA), and carbon monoxide (CO) in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIm][NTf2]) and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([EMIm][NTf2]) were determined by the transient grating (TG) spectroscopy under pressure from 0.1 to 200 MPa at 298 K and from 298 to 373 K under 0.1 MPa. Diffusion coefficients of these molecules at high temperatures in tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide ([P4441][NTf2]), and tetraoctylphosphonium bis(trifluoromethanesulfonyl)imide ([P8888][NTf2]), and also in the mixtures of [BMIm][NTf2], N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide ([Pp13][NTf2]), and trihexyltetradecylphosphonium bis(trifluoromethanesulfonyl)imide ([P66614][NTf2]) with ethanol or chloroform have been determined. Diffusion coefficients except in ILs of phosphonium cations were well scaled by the power law of T/η, i.e., (T/η)(P), where T and η are the absolute temperature and the viscosity, irrespective of the solvent species, pressure and temperature, and the compositions of mixtures. The values of the exponent P were smaller for the smaller size of the molecules. On the other hand, the diffusion coefficients in ILs of phosphonium cations with longer alkyl chains were larger than the values expected from the correlation obtained by other ILs and conventional liquids. The deviation becomes larger with increasing the number of carbon atoms of alkyl-chain of cation, and with decreasing the molecular size of diffusing molecules. The molecular size dependence of the diffusion coefficient was correlated by the ratio of the volume of the solute to that of the solvent as demonstrated by the preceding work (Kaintz et al., J. Phys. Chem. B 2013 , 117 , 11697 ). Diffusion coefficients have been well correlated with the power laws of both T/η and the relative volume of the solute to the solvent.

  5. Lung diffusing capacity in sub-Saharan Africans versus European Caucasians.

    PubMed

    Simaga, Bamodi; Forton, Kevin; Motoji, Yoshiki; Naeije, Robert; Faoro, Vitalie

    2017-01-10

    Single breath measurements of lung diffusing capacity (DL) for carbon monoxide (CO) and nitric oxide (NO) were performed in age-, sex-, weight- and height-matched 32 sub-Saharan Africans (13 women) and 32 Caucasian Europeans, and repeated in 14 of each group at 80% of maximum exercise capacity. In Africans versus Caucasians respectively, DLNO was 153±31 vs 176±38ml/mmHg/min at rest (P<0.001) and 210±48 vs 241±52ml/mmHg/min at exercise (P<0.01) while hemoglobin-adjusted DLCO was 29±6 vs 34±6ml/mmHg/min at rest (P<0.001), and 46±11 vs 51±13ml/mmHg/min at exercise (P<0.01). However there were no differences in DLCO/alveolar volume(VA) (KCO) and DLNO/VA(KNO). The sitting-to-standing height ratio was lower in the Africans. Differences in lung volume with respect to body height explain lower DLNO and DLCO in sub-Saharan Africans as compared to Caucasian Europeans.

  6. 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

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

    PubMed

    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.

  8. Pulmonary mechanical function and diffusion capacity after deep saturation dives.

    PubMed Central

    Thorsen, E; Segadal, K; Myrseth, E; Påsche, A; Gulsvik, A

    1990-01-01

    To assess the effects of deep saturation dives on pulmonary function, static and dynamic lung volumes, transfer factor for carbon monoxide (T1CO), delta-N2, and closing volume (CV) were measured before and after eight saturation dives to pressures of 3.1-4.6 MPa. The atmospheres were helium-oxygen mixtures with partial pressures of oxygen of 40-60 kPa. The durations of the dives were 14-30 days. Mean rate of decompression was 10.5-13.5 kPa/hour. A total of 43 divers were examined, six of whom took part in two dives, the others in one only. Dynamic lung volumes did not change significantly but total lung capacity (TLC) increased significantly by 4.3% and residual volume (RV) by 14.8% (p less than 0.05). CV was increased by 16.7% (p less than 0.01). The T1CO was reduced from 13.0 +/- 1.6 to 11.8 +/- 1.7 mmol/min/kPa (p less than 0.01) when corrected to a haemoglobin concentration of 146 g/l. Effective alveolar volume was unchanged. The increase in TLC and decrease in T1CO were correlated (r = -0.574, p less than 0.02). A control examination of 38 of the divers four to six weeks after the dives showed a partial normalisation of the changes. The increase in TLC, RV, and CV, and the decrease in T1CO, could be explained by a loss of pulmonary elastic tissue caused by inflammatory reactions induced by oxygen toxicity or venous gas emboli. PMID:2337532

  9. Molecular simulation and macroscopic modeling of the diffusion of hydrogen, carbon monoxide and water in heavy n-alkane mixtures.

    PubMed

    Makrodimitri, Zoi A; Unruh, Dominik J M; Economou, Ioannis G

    2012-03-28

    The self-diffusion coefficient of hydrogen (H(2)), carbon monoxide (CO) and water (H(2)O) in n-alkanes was studied by molecular dynamics simulation. Diffusion in a few pure n-alkanes (namely n-C(8), n-C(20), n-C(64) and n-C(96)) was examined. In addition, binary n-C(12)-n-C(96) mixtures with various compositions as well as more realistic five- and six-n-alkane component mixtures were simulated. In all cases, the TraPPE united atom force field was used for the n-alkane molecules. The force field for the mixture of n-alkanes was initially validated against experimental density values and was shown to be accurate. Moreover, macroscopic correlations for predicting diffusion coefficient of H(2), CO and H(2)O in n-alkanes and mixtures of n-alkanes were developed. The functional form of the correlation was based on the rough hard sphere theory (RHS). The correlation was applied to simulation data and an absolute average deviation (AAD) of 5.8% for pure n-alkanes and 3.4% for n-alkane mixtures was obtained. Correlation parameters vary in a systematic way with carbon number and so they can be used to provide predictions in the absence of any experimental or molecular simulation data. Finally, in order to reduce the number of adjustable parameters, for the n-alkane mixtures the "pseudo-carbon number" approach was used. This approach resulted in relatively higher deviation from MD simulation data (AAD of 18.2%); however, it provides a convenient and fast method to predict diffusion coefficients. The correlations developed here are expected to be useful for engineering calculations related to the design of the Gas-to-Liquid process.

  10. Diffusion capacity and CT measures of emphysema and airway wall thickness – relation to arterial oxygen tension in COPD patients

    PubMed Central

    Saure, Eirunn Waatevik; Bakke, Per Sigvald; Eagan, Tomas Mikal Lind; Aanerud, Marianne; Jensen, Robert Leroy; Grydeland, Thomas Blix; Johannessen, Ane; Nilsen, Roy Miodini; Thorsen, Einar; Hardie, Jon Andrew

    2016-01-01

    Background Decreased diffusing capacity of the lung for carbon monoxide (DLCO) is associated with emphysema. DLCO is also related to decreased arterial oxygen tension (PaO2), but there are limited data on associations between PaO2 and computed tomography (CT) derived measures of emphysema and airway wall thickness. Objective To examine whether CT measures of emphysema and airway wall thickness are associated with level of arterial oxygen tension beyond that provided by measurements of diffusion capacity and spirometry. Methods The study sample consisted of 271 smoking or ex-smoking COPD patients from the Bergen COPD Cohort Study examined in 2007–2008. Emphysema was assessed as percent of low-attenuation areas<−950 Hounsfield units (%LAA), and airway wall thickness as standardised measure at an internal perimeter of 10 mm (AWT-Pi10). Multiple linear regression models were fitted with PaO2 as the outcome variable, and %LAA, AWT-Pi10, DLCO and carbon monoxide transfer coefficient (KCO) as main explanatory variables. The models were adjusted for sex, age, smoking status, and haemoglobin concentration, as well as forced expiratory volume in one second (FEV1). Results Sixty two per cent of the subjects were men, mean (SD) age was 64 (7) years, mean (SD) FEV1 in percent predicted was 50 (15)%, and mean PaO2 (SD) was 9.3 (1.1) kPa. The adjusted regression coefficient (CI) for PaO2 was –0.32 (−0.04–(−0.019)) per 10% increase in %LAA (p<0.01). When diffusion capacity and FEV1 were added to the model, respectively, the association lost its statistical significance. No relationship between airway wall thickness and PaO2 was found. Conclusion CT assessment of airway wall thickness is not associated with arterial oxygen tension in COPD patients. Emphysema score measured by chest CT, is related to decreased PaO2, but cannot replace measurements of diffusion capacity in the clinical evaluation of hypoxaemia. PMID:27178139

  11. Emphysema Distribution and Diffusion Capacity Predict Emphysema Progression in Human Immunodeficiency Virus Infection

    PubMed Central

    Leung, Janice M; Malagoli, Andrea; Santoro, Antonella; Besutti, Giulia; Ligabue, Guido; Scaglioni, Riccardo; Dai, Darlene; Hague, Cameron; Leipsic, Jonathon; Sin, Don D.; Man, SF Paul; Guaraldi, Giovanni

    2016-01-01

    Background Chronic obstructive pulmonary disease (COPD) and emphysema are common amongst patients with human immunodeficiency virus (HIV). We sought to determine the clinical factors that are associated with emphysema progression in HIV. Methods 345 HIV-infected patients enrolled in an outpatient HIV metabolic clinic with ≥2 chest computed tomography scans made up the study cohort. Images were qualitatively scored for emphysema based on percentage involvement of the lung. Emphysema progression was defined as any increase in emphysema score over the study period. Univariate analyses of clinical, respiratory, and laboratory data, as well as multivariable logistic regression models, were performed to determine clinical features significantly associated with emphysema progression. Results 17.4% of the cohort were emphysema progressors. Emphysema progression was most strongly associated with having a low baseline diffusion capacity of carbon monoxide (DLCO) and having combination centrilobular and paraseptal emphysema distribution. In adjusted models, the odds ratio (OR) for emphysema progression for every 10% increase in DLCO percent predicted was 0.58 (95% confidence interval [CI] 0.41–0.81). The equivalent OR (95% CI) for centrilobular and paraseptal emphysema distribution was 10.60 (2.93–48.98). Together, these variables had an area under the curve (AUC) statistic of 0.85 for predicting emphysema progression. This was an improvement over the performance of spirometry (forced expiratory volume in 1 second to forced vital capacity ratio), which predicted emphysema progression with an AUC of only 0.65. Conclusion Combined paraseptal and centrilobular emphysema distribution and low DLCO could identify HIV patients who may experience emphysema progression. PMID:27902753

  12. Effect of yoga regimen on lung functions including diffusion capacity in coronary artery disease patients: A randomized controlled study

    PubMed Central

    Yadav, Asha; Singh, Savita; Singh, KP; Pai, Preeti

    2015-01-01

    Background: Lung functions are found to be impaired in coronary artery disease (CAD), congestive heart failure, left ventricular dysfunction, and after cardiac surgery. Diffusion capacity progressively worsens as the severity of CAD increases due to reduction in lung tissue participating in gas exchange. Aims and Objectives: Pranayama breathing exercises and yogic postures may play an impressive role in improving cardio-respiratory efficiency and facilitating gas diffusion at the alveolo-capillary membrane. This study was done to see the effect of yoga regimen on lung functions particularly diffusion capacity in CAD patients. Materials and Methods: A total of 80 stable CAD patients below 65 years of age of both sexes were selected and randomized into two groups of 40 each. Group I CAD patients were given yoga regimen for 3 months which consisted of yogic postures, pranayama breathing exercises, dietary modification, and holistic teaching along with their conventional medicine while Group II CAD patients were put only on conventional medicine. Lung functions including diffusion capacity were recorded thrice in both the groups: 0 day as baseline, 22nd day and on 90th day by using computerized MS medisoft Cardio-respiratory Instrument, HYP’AIR Compact model of cardio-respiratory testing machine was manufactured by P K Morgan, India. The recorded parameters were statistically analyzed by repeated measures ANOVA followed by Tukey's test in both the groups. Cardiovascular parameters were also compared before and after intervention in both the groups. Results: Statistically significant improvements were seen in slow vital capacity, forced vital capacity, peak expiratory flow rate, maximum voluntary ventilation, and diffusion factor/ transfer factor of lung for carbon monoxide after 3 months of yoga regimen in Group I. Forced expiratory volume in 1st sec (FEV1), and FEV1 % also showed a trend toward improvement although not statistically significant. HR, SBP and DBP also

  13. Normal diffusing capacity in patients with PiZ alpha(1)-antitrypsin deficiency, severe airflow obstruction, and significant radiographic emphysema.

    PubMed

    Wilson, J S; Galvin, J R

    2000-09-01

    alpha(1)-Antitrypsin deficiency is usually suspected clinically in young adults with irreversible airflow obstruction that is out of proportion to their smoking history. Many patients with alpha(1)-antitrypsin deficiency receive an initial diagnosis of asthma or chronic bronchitis. Measurement of the diffusing capacity of the lung for carbon monoxide (DLCO) has been recommended as a way to help distinguish emphysema from asthma and chronic bronchitis. In this article, we describe four patients with severe alpha(1)-antitrypsin deficiency, each of whom had a repeatedly normal DLCO despite having a significant component of fixed airway obstruction and prominent panacinar emphysema on high-resolution CT scan (HRCT). Each patient also demonstrated significant bronchodilator responsiveness, and two patients received an initial diagnosis of asthma. Potential explanations for these findings are discussed. We report these findings to illustrate the limitations of DLCO in this setting. alpha(1)-Antitrypsin deficiency should be considered in patients with fixed airway obstruction that is out of proportion to their age and smoking history, regardless of their diffusing capacity and response to bronchodilators.

  14. 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

  15. 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

  16. 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.

  17. An infant with pulmonary interstitial glycogenosis: clinical improvement is associated with improvement in the pulmonary diffusion capacity.

    PubMed

    Ehsan, Zarmina; Montgomery, Gregory S; Tiller, Christina; Kisling, Jeffrey; Chang, Daniel V; Tepper, Robert S

    2014-03-01

    Pulmonary interstitial glycogenosis (PIG) is an idiopathic interstitial lung disease of infants. The underlying pulmonary pathophysiology of PIG has not been well characterized. Herein we report a term-gestation infant who presented with persistent tachypnea and hypoxia. A chest CT scan demonstrated a diffuse ground glass appearance and lung biopsy demonstrated increased alveolar septae cellularity with glycogen-containing cells, consistent with a diagnosis of PIG. At 3 months of age, pulmonary function testing included: pre- and post-bronchodilator forced expiratory flows using the raised-volume technique and the ratio of pulmonary diffusing capacity for carbon monoxide to alveolar volume (DLCO /VA ). He was prescribed 5 days of oral prednisolone (2mg/kg/day) and pulmonary function testing (PFT) was repeated at 5, 13, and 20 months of age. Initial PFTs demonstrated reduced forced vital capacity (FVC: Z-score = -2.36) and an increased ratio of forced expiratory volume in 0.5 sec to FVC (FEV0.5/FVC: Z-score = 1.15) with no significant change following an inhaled bronchodilator. There was also a marked reduction in DLCO /VA (Z-score = -4.74) compared to age-matched controls. Follow-up demonstrated progressive clinical improvement as well as an increase in Z-FVC and normalization of DLCO /VA . Our in vivo physiological findings are consistent with previous reports that symptom resolution correlated with histological thinning of the alveolar septae upon repeat lung biopsy. The restrictive lung disease we observed is consistent with expected reduced compliance of an alveolar interstitial lung process like PIG, whereas the absence of a reduction in FEV0.5/FVC confirms the absence of obstructive airway disease.

  18. Effect of the cold pressor test on diffusing capacity. Comparison of normal subjects and those with Raynaud's disease and progressive systemic sclerosis.

    PubMed

    Miller, M J

    1983-09-01

    Single-breath carbon monoxide diffusing capacity (Dsb) was measured before and during immersion of one hand in ice water (cold pressor test) in the following three groups of subjects: (1) normal subjects; (2) patients with isolated Raynaud's disease; and (3) patients with Raynaud's phenomenon and progressive systemic sclerosis. No change in Dsb was found in normal subjects or patients with progressive systemic sclerosis. Patients with isolated Raynaud's disease showed a rise in Dsb during cold pressor testing, the mean increase being 8 percent. These results suggest that a rise in Dsb during exposure to cold is a response unique to patients with isolated Raynaud's disease or Raynaud's phenomenon without progressive systemic sclerosis, and not a normal physiologic response to cold. The lack of change in Dsb in response to cold in progressive systemic sclerosis, interpreted by other authors as an indicator of pulmonary vascular disease, resembles the normal response to a challenge with cold.

  19. On evolutionary stability of carrying capacity driven dispersal in competition with regularly diffusing populations.

    PubMed

    Korobenko, L; Braverman, E

    2014-11-01

    Two competing populations in spatially heterogeneous but temporarily constant environment are investigated: one is subject to regular movements to lower density areas (random diffusion) while the dispersal of the other is in the direction of the highest per capita available resources (carrying capacity driven diffusion). The growth of both species is subject to the same general growth law which involves Gilpin-Ayala, Gompertz and some other equations as particular cases. The growth rate, carrying capacity and dispersal rate are the same for both population types, the only difference is the dispersal strategy. The main result of the paper is that the two species cannot coexist (unless the environment is spatially homogeneous), and the carrying capacity driven diffusion strategy is evolutionarily stable in the sense that the species adopting this strategy cannot be invaded by randomly diffusing population. Moreover, once the invasive species inhabits some open nonempty domain, it would spread over any available area bringing the native species diffusing randomly to extinction. One of the important technical results used in the proofs can be interpreted in the form that the limit solution of the equation with a regular diffusion leads to lower total population fitness than the ideal free distribution.

  20. A Monte Carlo-based model for steady-state diffuse reflectance spectrometry in human skin: estimation of carbon monoxide concentration in livor mortis.

    PubMed

    Bohnert, M; Walther, R; Roths, T; Honerkamp, J

    2005-11-01

    In terms of physics, the skin can be regarded as an optically turbid medium in which the light is mainly scattered by the collagen fibers, mitochondria and cell nuclei, whereas the absorption is determined by the content of reduced hemoglobin, oxyhemoglobin, bilirubin, and melanin. When the measuring geometry and the illumination spectrum are known, the optical characteristics of the skin can be approximately described by the diffusion and absorption coefficients. These values define the diffusion and absorption probability per unit distance traveled for each wavelength. Based on these parameters, a mathematical skin model was developed with the help of Monte Carlo simulations. By implementing the absorption coefficient of carbon monoxide hemoglobin (CO-Hb) into the skin model, the authors wanted to investigate whether this method is suitable to determine the CO-Hb concentration from spectral reflectance curves of livores. The investigations performed on 28 deaths from CO poisoning so far showed that this is generally possible. In almost all cases, the actual CO-Hb values could be estimated correctly by using the Monte Carlo simulations.

  1. The effect of aging and cardiorespiratory fitness on the lung diffusing capacity response to exercise in healthy humans.

    PubMed

    Coffman, Kirsten E; Carlson, Alex R; Miller, Andrew D; Johnson, Bruce D; Taylor, Bryan Joseph

    2017-03-23

    Aging is associated with deterioration in the structure and function of the pulmonary circulation. We characterized the lung diffusing capacity for carbon monoxide (DLCO), alveolar-capillary membrane conductance (DmCO), and pulmonary-capillary blood volume (VC) response to discontinuous incremental exercise at 25, 50, 75, and 90% of peak work (Wpeak) in four groups: 1) Young [27 ± 3 y, maximal oxygen consumption (V̇O2max) 110 ± 18% age-predicted]; 2) Young Highly-Fit (27 ± 3 y, V̇O2max 147 ± 8% age-predicted); 3) Old (69 ± 5 y, V̇O2max 116 ± 13% age-predicted); and 4) Old Highly-Fit (65 ± 5 y, V̇O2max 162 ± 18% age-predicted). At rest and at 90% Wpeak, DLCO, DmCO, and VC were decreased with age. At 90% Wpeak, DLCO, DmCO and VC were greater in Old Highly-Fit vs. Old adults. The slope of the DLCO-cardiac output (Q̇) relationship from rest to end-exercise at 90% Wpeak was not different between Young, Young Highly-Fit, Old and Old Highly-Fit (1.35 vs. 1.44 vs. 1.10 vs. 1.35 mlCO·mmHg(-1)·Lblood(-1), P = 0.388), with no evidence of a plateau in this relationship during exercise; this was also true for DmCO-Q̇ and VC-Q̇. V̇O2max was positively correlated with: 1) DLCO, DmCO, and VC at rest; 2) the rest to end-exercise change in DLCO, DmCO, and VC In conclusion, these data suggest that despite the age-associated deterioration in the structure and function of the pulmonary circulation, expansion of the pulmonary capillary network does not become limited during exercise in healthy individuals regardless of age or cardiorespiratory fitness level.

  2. 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

  3. 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.

  4. 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

  5. Capacity and Delay Spread in Multilayer Diffusion-Based Molecular Communication (DBMC) Channel.

    PubMed

    Md Mustam, Saizalmursidi; Syed-Yusof, Sharifah K; Zubair, Suleiman

    2016-10-01

    In nanoscale communication, diffusion-based molecular communication (DBMC) in which information is encoded into molecule patterns by a transmitter nanomachine, has emerged as a promising communication system, particularly for biomedical and healthcare applications. Although, numerous studies have been conducted to evaluate and analyze DBMC systems, investigation on DBMC system through a multilayer channel has received less attention. The aims of this paper are to formulate channel characteristics and to evaluate the performance of multilayer DBMC channel in terms of delay spread and capacity. In this paper, the propagation of molecules over an n- layer channel is assumed to follow the Brownian motion and subjected to Fick's law of diffusion. Fourier transform is used to convert time to frequency domain functions. Besides, the multilayer channel is considered as a linear and deterministic channel. For the performance evaluation, the air-water-blood plasma medium representing the simplified multilayer diffusion model in the respiratory system was chosen. It was found that a high channel capacity can be achieved with wide transmission bandwidth, short transmission distance, and high averaged transmitted power. In addition, the findings showed that channel delay spread increases as both the transmission distance, and the pulse duration increased. By setting the symbol duration greater than the pulse duration or delay spread, an inter-symbol interference problem due to previous molecules transmission can be mitigated. These findings can be used as a guide in the development and fabrication of future artificial nanocommunication and nanonetworks systems involving multilayer transmission medium.

  6. Effect of aerobic fitness on capillary blood volume and diffusing membrane capacity responses to exercise

    PubMed Central

    Tedjasaputra, Vincent; Bouwsema, Melissa M.

    2016-01-01

    Key points Endurance trained athletes exhibit enhanced cardiovascular function compared to non‐athletes, although it is considered that exercise training does not enhance lung structure and function.An increased pulmonary capillary blood volume at rest is associated with a higher V˙O2 max .In the present study, we compared the diffusion capacity, pulmonary capillary blood volume and diffusing membrane capacity responses to exercise in endurance‐trained males compared to non‐trained males.Exercise diffusion capacity was greater in athletes, secondary to an increased membrane diffusing capacity, and not pulmonary capillary blood volume.Endurance‐trained athletes appear to have differences within the pulmonary membrane that facilitate the increased O2 demand needed for high‐level exercise. Abstract Endurance‐trained athletes exhibit enhanced cardiovascular function compared to non‐athletes, allthough it is generally accepted that exercise training does not enhance lung structure and function. Recent work has shown that an increased resting pulmonary capillary blood volume (V C) is associated with a higher maximum oxygen consumption (V˙O2 max ), although there have been no studies to date examining how aerobic fitness affects the V C response to exercise. Based on previous work, we hypothesized that endurance‐trained athletes will have greater V C compared to non‐athletes during cycling exercise. Fifteen endurance‐trained athletes (HI: V˙O2 max 64.6 ± 1.8 ml kg−1 min−1) and 14 non‐endurance trained males (LO: V˙O2 max 45.0 ± 1.2 ml kg−1 min−1) were matched for age and height. Haemoglobin‐corrected diffusion capacity (DLCO), V C and diffusing membrane capacity (D M) were determined using the Roughton and Forster (1957) multiple fraction of inspired O2 (FIO2)‐DLCO method at baseline and during incremental cycle exercise up to 90% of peak O2 consumption. During exercise, both groups exhibited increases in DLCO, D M and V C

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. Carbon Monoxide (CO)

    MedlinePlus

    ... United States Environmental Protection Agency Search Search Indoor Air Quality (IAQ) Share Facebook Twitter Google+ Pinterest Contact Us Carbon Monoxide's Impact on Indoor Air Quality On this page: Overview Sources of Carbon Monoxide ...

  13. Instrumental carbon monoxide dosimetry.

    PubMed

    Stetter, J R; Rutt, D R

    1980-10-01

    Modern technology for the ambient monitoring of carbon monoxide has been developed to produce a portable electrochemical instrument capable of the personal exposure to carbon monoxide. The performance characteristics of this device have been studied so that the unambiguous interpretation of field data could be performed. A study of the carbon monoxide exposure in a light manufacturing facility illustrate that effective dosimetry can be performed with expectations of accuracy typically better than +/- 15%, and that voluntary carbon monoxide exposures such as smoking were a significant contribution to the individual's exposure. Significant definition of the carbon monoxide exposure profile can be achieved with an instrument approach to the collection of the dosimetric data.

  14. Nitrogen monoxide and carbon monoxide transfer interpretation: state of the art.

    PubMed

    Martinot, Jean Benoit; Guénard, Hervé; Dinh-Xuan, Anh-Tuan; Gin, Henri; Dromer, Claire

    2015-11-17

    Just a few clinicians routinely measure the subcomponents of the lung diffusing capacity for Carbone monoxide (DLCO ). This is because the measurement of membrane and blood conductances for CO (DmCO and DbCO  = θCO  × Vc , respectively) by the classic Roughton and Forster method is complicated and time consuming. In addition, it mistakenly assumes a close relationship between alveolar oxygen partial pressure (PAO2 ) and mean intracapillary oxygen partial pressure (PcapO2 ) which is the true determinant of specific conductance of haemoglobin for CO (θCO ). Besides that, the critical multistep oxygenation method along with different linear equations relating 1/θCO to PcapO2 gave highly scattered DmCO and Vc values. The Dm and Vc can also be derived from a simultaneous measurement of DLNO and DLCO with the blood resistance for NO assumed to be negligible. However, recent in vitro and in vivo experiments point towards a finite value of θNO (about 4·5 mlNO  × mlblood(-1)  × min(-1)  × mmHg(-1) ). Putting together the arguments and our clinical data allows us to report here the state of the art in partitioning the CO diffusing capacity into its constitutive components, with the goal to encourage further studies examining the sensitivity of DmCO and Vc to alterations observed in parenchymal diseases.

  15. 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

  16. Accidental carbon monoxide poisoning.

    PubMed

    Zeller, W P; Miele, A; Suarez, C; Hannigan, J; Hurley, R M

    1984-12-01

    In this case report of an accidental automobile carbon monoxide poisoning, we identify the following risk factors: freezing temperature, young passenger age, location in the rear of the auto, smaller patient mass, and auto disrepair. The pathogenesis of carbon monoxide poisoning is reviewed. Emergency treatment and suggested criteria for hyperbaric oxygen use in pediatric patients are discussed.

  17. Lifetime Occupational Exposure to Dusts, Gases and Fumes Is Associated with Bronchitis Symptoms and Higher Diffusion Capacity in COPD Patients

    PubMed Central

    Rodríguez, Esther; Ferrer, Jaume; Zock, Jan-Paul; Serra, Ignasi; Antó, Josep M.; de Batlle, Jordi; Kromhout, Hans; Vermeulen, Roel; Donaire-González, David; Benet, Marta; Balcells, Eva; Monsó, Eduard; Gayete, Angel; Garcia-Aymerich, Judith

    2014-01-01

    Background Occupational exposure to dusts, gases and fumes has been associated with reduced FEV1 and sputum production in COPD patients. The effect of occupational exposure on other characteristics of COPD, especially those reflecting emphysema, has not been studied in these patients. Methods We studied 338 patients hospitalized for a first exacerbation of COPD in 9 Spanish hospitals, obtaining full occupational history in a face-to-face interview; job codes were linked to a job exposure matrix for semi-quantitative estimation of exposure to mineral/biological dust, and gases/fumes for each job held. Patients underwent spirometry, diffusing capacity testing and analysis of gases in stable conditions. Quality of life, dyspnea and chronic bronchitis symptoms were determined with a questionnaire interview. A high- resolution CT scan was available in 133 patients. Results 94% of the patients included were men, with a mean age of 68(8.5) years and a mean FEV1% predicted 52 (16). High exposure to gases or fumes was associated with chronic bronchitis, and exposure to mineral dust and gases/fumes was associated with higher scores for symptom perception in the St. George’s questionnaire. No occupational agent was associated with a lower FEV1. High exposure to all occupational agents was associated with better lung diffusion capacity, in long-term quitters. In the subgroup with CT data, patients with emphysema had 18% lower DLCO compared to those without emphysema. Conclusions In our cohort of COPD patients, high exposure to gases or fumes was associated with chronic bronchitis, and high exposure to all occupational agents was consistently associated with better diffusion capacity in long-term quitters. PMID:24516659

  18. 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.

  19. Carbon monoxide poisoning

    MedlinePlus

    ... any major gas-burning appliances (such as a furnace or water heater). Many carbon monoxide poisonings occur in the winter months when furnaces, gas fireplaces, and portable heaters are being used ...

  20. Normal values for single exhalation diffusing capacity and pulmonary capillary blood flow in sitting, supine positions, and during mild exercise.

    PubMed

    Huang, Y C; Helms, M J; MacIntyre, N R

    1994-02-01

    Previous approaches to the measurements of pulmonary diffusing capacity (DL) and pulmonary capillary blood flow (QC) utilized either the rebreathing or the single inhalation technique in conjunction with radioisotope gas and mass spectrometry. In the present study, we utilized a newly developed rapid infrared analyzer in conjunction with the slow single exhalation technique on 100 healthy volunteers to establish normal values for DL and QC under sitting, supine, and exercise conditions. The exercise level was determined by a target heart rate: HRex = ([HRmax - HRrest]/3) + HRrest. Prediction equations based on regressions on age, sex, height, or weight were then computed for sitting, supine, and exercise values. We found that mean DL and QC increased by approximately 12 percent and 8 percent, respectively, from sitting to supine posture, and by approximately 30 percent and 100 percent, respectively, from sitting (rest) to mild exercise. These results provided a database for further studies in the single exhalation method in various clinical settings.

  1. Reconstruction of thermal property distributions of tissue phantoms from temperature measurements--thermal conductivity, thermal capacity and thermal diffusivity.

    PubMed

    Sumi, Chikayoshi; Yanagimura, Hiroyuki

    2007-05-21

    We report robust noninvasive techniques for reconstructing the thermal properties of living tissues, such as thermal conductivity, thermal capacity and thermal diffusivity, for the diagnosis, monitoring and planning of thermal treatments. Internal temperature distributions can be measured using ultrasonic imaging or magnetic resonance imaging. Provided that the reference thermal properties are given in the region of interest as initial conditions, by solving bioheat transfer equations as simultaneous first-order partial differential equations having temperature distributions as inhomogeneous coefficients, we can determine thermal property distributions. A novel regularized numerical solution is also presented to realize useful, unique, stable reconstructions of the thermal property distributions. To verify the feasibility of the numerical solution, simulations and ultrasonic phantom experiments are conducted. The reconstruction of perfusion by blood flow and thermal source/sink by this approach is also addressed.

  2. Carbon Monoxide (CO) Poisoning Prevention

    MedlinePlus

    ... What's this? Submit Button Past Emails CDC Features Carbon Monoxide (CO) Poisoning Prevention Language: English Español (Spanish) ... tornadoes), using alternative sources of power can cause carbon monoxide (CO) to build up in a home ...

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. Analysis of carbon monoxide.

    PubMed

    Widdop, Brian

    2002-07-01

    The degree of exposure to carbon monoxide is most often assessed by measuring the blood carboxyhaemoglobin saturation. This measurement is relevant to investigations of acute accidental or deliberate poisoning and of chronic exposure in a domestic or work place environment. Simple spectrophotometric methods based on differential protein precipitation or dithionite reduction are prone to interference from other haemoglobin pigments and are imprecise for low-level estimations. Automated spectrophotometric devices (CO-oximeters) that estimate simultaneously total haemoglobin, percentage oxyhaemoglobin and percentage carboxyhaemoglobin have acceptable accuracy for carboxyhaemoglobin saturation levels of > 5% and are recommended for most clinical purposes. For the investigation of low-level exposure and the detection of increased haemolysis in neonates, more sensitive methods involving the release of carbon monoxide and its measurement by gas chromatography are required. Gas chromatographic methods are also appropriate when examining post-mortem blood samples where putrefaction or heat stress has resulted in a significant change in haemoglobin composition.

  8. Carbon Monoxide Targeting Mitochondria

    PubMed Central

    Queiroga, Cláudia S. F.; Almeida, Ana S.; Vieira, Helena L. A.

    2012-01-01

    Mitochondria present two key roles on cellular functioning: (i) cell metabolism, being the main cellular source of energy and (ii) modulation of cell death, by mitochondrial membrane permeabilization. Carbon monoxide (CO) is an endogenously produced gaseoustransmitter, which presents several biological functions and is involved in maintaining cell homeostasis and cytoprotection. Herein, mitochondrion is approached as the main cellular target of carbon monoxide (CO). In this paper, two main perspectives concerning CO modulation of mitochondrial functioning are evaluated. First, the role of CO on cellular metabolism, in particular oxidative phosphorylation, is discussed, namely, on: cytochrome c oxidase activity, mitochondrial respiration, oxygen consumption, mitochondrial biogenesis, and general cellular energetic status. Second, the mitochondrial pathways involved in cell death inhibition by CO are assessed, in particular the control of mitochondrial membrane permeabilization. PMID:22536507

  9. [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.

  10. Medical helicopters: carbon monoxide risk?

    PubMed

    Poulton, T J

    1987-02-01

    Carbon monoxide exposure of medical personnel working beneath the turning rotor of a medical helicopter appeared to cause mild clinical illness. We measured the carbon monoxide levels found in various locations beneath the rotor of a jet helicopter under two different conditions. Carbon monoxide levels ranged from 8-76 ppm depending on location of sampling and speed of operation of the engine. This level of carbon monoxide is potentially a problem, as is the inhalation of jet fuel vapor, when working beneath the rotors of an operating helicopter.

  11. Carbon monoxide poisoning.

    PubMed

    Guzman, Jorge A

    2012-10-01

    Carbon monoxide (CO) poisoning is the leading cause of death as a result of unintentional poisoning in the United States. CO toxicity is the result of a combination of tissue hypoxia-ischemia secondary to carboxyhemoglobin formation and direct CO-mediated damage at a cellular level. Presenting symptoms are mostly nonspecific and depend on the duration of exposure and levels of CO. Diagnosis is made by prompt measurement of carboxyhemoglobin levels. Treatment consists of the patient's removal from the source of exposure and the immediate administration of 100% supplemental oxygen in addition to aggressive supportive measures. The use of hyperbaric oxygen is controversial.

  12. Relation between Dopamine Synthesis Capacity and Cell-Level Structure in Human Striatum: A Multi-Modal Study with Positron Emission Tomography and Diffusion Tensor Imaging

    PubMed Central

    Kawaguchi, Hiroshi; Obata, Takayuki; Takano, Harumasa; Nogami, Tsuyoshi; Suhara, Tetsuya; Ito, Hiroshi

    2014-01-01

    Positron emission tomography (PET) study has shown that dopamine synthesis capacity varied among healthy individuals. This interindividual difference might be due to a difference in the cell-level structure of presynaptic dopaminergic neurons, i.e., cellular density and/or number. In this study, the relations between the dopamine synthesis capacity measured by PET and the parameter estimates in diffusion tensor imaging (DTI) in striatal subregions were investigated in healthy human subjects. DTI and PET studies with carbon-11 labeled L-DOPA were performed in ten healthy subjects. Age-related changes in the above parameters were also considered. Fractional anisotropy showed a significant positive correlation with age in the posterior caudate. There was significant negative correlation between dopamine synthesis capacity and mean diffusivity in the posterior caudate and putamen. Assuming that mean diffusivity reflects the density of wide-spreading axonal terminals in the striatum, the result suggests that dopamine synthesis may be related to the density of dopaminergic neuronal fibers. It is evident that PET/DTI combined measurements can contribute to investigations of the pathophysiology of neuropsychiatric diseases involving malfunction of dopaminergic neurons. PMID:24498218

  13. Diffusion Profiles of Health Beneficial Components from Goji Berry (Lyceum barbarum) Marinated in Alcohol and Their Antioxidant Capacities as Affected by Alcohol Concentration and Steeping Time.

    PubMed

    Song, Yang; Xu, Baojun

    2013-01-25

    The fruit (goji berry) of Lycium barbarum, a traditional Chinese medicine, has been widely used in health diets due to its potential role in the prevention of chronic diseases. One of the most popular applications of goji berry is to make goji wine in China by steeping goji berry in grain liquor. However, how the steeping process affects antioxidant capacities and phytochemicals of goji berry is not yet fully understood. Therefore, to provide scientific data for the utilization of goji berry in the nutraceutical industry, the diffusion rate of betaine, β-carotene, phenolic compounds in goji berry and their antioxidant capacities affected by alcohol concentration and steeping time were determined by UV-Visible spectrophotometer. The results showed that low alcohol concentration (15% or 25%) would promote the diffusion of betaine and increase antioxidant activity, while high concentration (55% or 65%) would generally increase the diffusion of flavonoids and reduce antioxidant activity. The steeping time had no significant effect on the diffusion of phenolic compounds and antioxidant activities. However, all goji berry wine steeped for 14 days with different alcohol concentrations exhibited the highest betaine concentration. Current findings provide useful information for the nutraceutical industries to choose proper steeping time and alcohol concentration to yield desired health promotion components from goji.

  14. Diffusion Profiles of Health Beneficial Components from Goji Berry (Lyceum barbarum) Marinated in Alcohol and Their Antioxidant Capacities as Affected by Alcohol Concentration and Steeping Time

    PubMed Central

    Song, Yang; Xu, Baojun

    2013-01-01

    The fruit (goji berry) of Lycium barbarum, a traditional Chinese medicine, has been widely used in health diets due to its potential role in the prevention of chronic diseases. One of the most popular applications of goji berry is to make goji wine in China by steeping goji berry in grain liquor. However, how the steeping process affects antioxidant capacities and phytochemicals of goji berry is not yet fully understood. Therefore, to provide scientific data for the utilization of goji berry in the nutraceutical industry, the diffusion rate of betaine, β-carotene, phenolic compounds in goji berry and their antioxidant capacities affected by alcohol concentration and steeping time were determined by UV-Visible spectrophotometer. The results showed that low alcohol concentration (15% or 25%) would promote the diffusion of betaine and increase antioxidant activity, while high concentration (55% or 65%) would generally increase the diffusion of flavonoids and reduce antioxidant activity. The steeping time had no significant effect on the diffusion of phenolic compounds and antioxidant activities. However, all goji berry wine steeped for 14 days with different alcohol concentrations exhibited the highest betaine concentration. Current findings provide useful information for the nutraceutical industries to choose proper steeping time and alcohol concentration to yield desired health promotion components from goji. PMID:28239094

  15. [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.

  16. A MoO2 sheet as a promising electrode material: ultrafast Li-diffusion and astonishing Li-storage capacity

    NASA Astrophysics Data System (ADS)

    Zhou, Yungang; Geng, Cheng

    2017-03-01

    The potential of MoO2 crystal as an electrode material is reported, and nanostructural MoO2 systems, including nanoparticles, nanospheres, nanobelts and nanowires, were synthesized and proved to be advanced electrode materials. A two-dimensional (2D) geometric structure represents an extreme of surface-to-volume ratio, and thus is more suitable as an electrode material in general. Stimulated by the recent fabrication of 2D MoO2, we adopted an ab initio molecular dynamics simulation and density functional theory calculation to study the stability and electrochemical properties of a MoO2 sheet. Identified by a phonon dispersion curve and potential energy curve calculations, the MoO2 sheet proved to be dynamically and thermally stable. After lithiation, similar to most promising 2D structures, we found that a Li atom can strongly adsorb on a MoO2 sheet, and the lithiated MoO2 sheet presented excellent metallic properties. Note that, compared with most promising 2D structures, we unexpectedly revealed that the diffusion barrier of the Li atom on the MoO2 sheet was much lower and the storage capacity of the MoO2 sheet was much larger. The calculated energy barrier for the diffusion of Li on the MoO2 sheet was only 75 meV, and, due to multilayer adsorption, the theoretical capacity of the MoO2 sheet can reach up to 2513 mA h g‑1. Benefiting from general properties, such as strong Li-binding and excellent conductivity, and unique phenomena, such as ultrafast diffusion capacity and astonishing storage capacity, we highlight a new promising electrode material for the Li-ion battery.

  17. Relationship between water departure and capacity loss of α and β-PbO 2 using an all solid-state system: Estimation of proton diffusion coefficient

    NASA Astrophysics Data System (ADS)

    Zerroual, L.; Fitas, R.; Djellouli, B.; Chelali, N.

    The proton diffusion coefficient for both fresh and heat-treated (140 and 230 °C, respectively) α and β-PbO 2 electrodes was estimated at room temperature using Galvanostatic Intermittent Titration Technique (GITT). PbO 2 samples were prepared by electroformation of cured plates. HSbO 3· xH 2O with a conductivity of 3.29 × 10 -3 Ω -1 cm -1, was used as solid protonic conductor (SPC) electrolyte. It was found that when structural water is removed, the capacity of both α and β-PbO 2 electrodes decreases and the ohmic drop increases. The departure of structural water affects considerably the value of proton diffusion coefficient.

  18. An evaluation of ferrihydrite- and Metsorb™-DGT techniques for measuring oxyanion species (As, Se, V, P): effective capacity, competition and diffusion coefficients.

    PubMed

    Price, Helen L; Teasdale, Peter R; Jolley, Dianne F

    2013-11-25

    This study investigated several knowledge gaps with respect to the diffusive gradients in thin films (DGT) technique for measurement of oxyanions (As(III), As(V), Se(IV), Se(VI), PO4(3-), and V(V)) using the ferrihydrite and Metsorb™ binding layers. Elution efficiencies for each binding layer were higher with 1:20 dilutions, as analytical interferences for ICP-MS were minimised. Diffusion coefficients measured by diffusion cell and by DGT time-series experiments were found to agree well and generally agreed with previously reported values, although a range of diffusion coefficients have been reported for inorganic As and Se species. The relative binding affinity for both ferrihydrite and Metsorb™ was PO4(3-) ≈ As(V)>V(V) ≈ As(III)>Se(IV) > Se(VI) and effective binding capacities were measured in single ion solutions, and spiked synthetic freshwater and seawater, advising practical decisions about DGT monitoring. Under the conditions tested the performance of both ferrihydrite and Metsorb™ binding layers was directly comparable for As(V), As(III) Se(IV), V(V) and PO4(3-) over a deployment spanning ≤ 2 days for both freshwater and seawater. In order to return quantitative data for several analytes we recommend that the DGT method using either ferrihydrite or Metsorb™ be deployed for a maximum of 2 days in marine waters likely to contain high levels of the most strongly adsorbing oxyanions contaminants. The high pH, the competitive ions present in seawater and the identity of co-adsorbing ions affect the capacity of each binding layer for the analytes of interest. In freshwaters, longer deployment times can be considered but the concentration and identity of co-adsorbing ions may impact on quantitative uptake of Se(IV). This study found ferrihydrite-DGT outperformed Metsorb-DGT while previous studies have found the opposite, with variation in binding materials masses used being a likely reason. Clearly, preparation of both binding layers should always be

  19. A MoO2 sheet as a promising electrode material: ultrafast Li-diffusion and astonishing Li-storage capacity.

    PubMed

    Zhou, Yungang; Geng, Cheng

    2017-03-10

    The potential of MoO2 crystal as an electrode material is reported, and nanostructural MoO2 systems, including nanoparticles, nanospheres, nanobelts and nanowires, were synthesized and proved to be advanced electrode materials. A two-dimensional (2D) geometric structure represents an extreme of surface-to-volume ratio, and thus is more suitable as an electrode material in general. Stimulated by the recent fabrication of 2D MoO2, we adopted an ab initio molecular dynamics simulation and density functional theory calculation to study the stability and electrochemical properties of a MoO2 sheet. Identified by a phonon dispersion curve and potential energy curve calculations, the MoO2 sheet proved to be dynamically and thermally stable. After lithiation, similar to most promising 2D structures, we found that a Li atom can strongly adsorb on a MoO2 sheet, and the lithiated MoO2 sheet presented excellent metallic properties. Note that, compared with most promising 2D structures, we unexpectedly revealed that the diffusion barrier of the Li atom on the MoO2 sheet was much lower and the storage capacity of the MoO2 sheet was much larger. The calculated energy barrier for the diffusion of Li on the MoO2 sheet was only 75 meV, and, due to multilayer adsorption, the theoretical capacity of the MoO2 sheet can reach up to 2513 mA h g(-1). Benefiting from general properties, such as strong Li-binding and excellent conductivity, and unique phenomena, such as ultrafast diffusion capacity and astonishing storage capacity, we highlight a new promising electrode material for the Li-ion battery.

  20. 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.

  1. Limitations to oxygen transport and utilization during sprint exercise in humans: evidence for a functional reserve in muscle O2 diffusing capacity.

    PubMed

    Calbet, José A L; Losa-Reyna, José; Torres-Peralta, Rafael; Rasmussen, Peter; Ponce-González, Jesús Gustavo; Sheel, A William; de la Calle-Herrero, Jaime; Guadalupe-Grau, Amelia; Morales-Alamo, David; Fuentes, Teresa; Rodríguez-García, Lorena; Siebenmann, Christoph; Boushel, Robert; Lundby, Carsten

    2015-10-15

    To determine the contribution of convective and diffusive limitations to V̇(O2peak) during exercise in humans, oxygen transport and haemodynamics were measured in 11 men (22 ± 2 years) during incremental (IE) and 30 s all-out cycling sprints (Wingate test, WgT), in normoxia (Nx, P(IO2): 143 mmHg) and hypoxia (Hyp, P(IO2): 73 mmHg). Carboxyhaemoglobin (COHb) was increased to 6-7% before both WgTs to left-shift the oxyhaemoglobin dissociation curve. Leg V̇(O2) was measured by the Fick method and leg blood flow (BF) with thermodilution, and muscle O2 diffusing capacity (D(MO2)) was calculated. In the WgT mean power output, leg BF, leg O2 delivery and leg V̇(O2) were 7, 5, 28 and 23% lower in Hyp than Nx (P < 0.05); however, peak WgT D(MO2) was higher in Hyp (51.5 ± 9.7) than Nx (20.5 ± 3.0 ml min(-1) mmHg(-1), P < 0.05). Despite a similar P(aO2) (33.3 ± 2.4 and 34.1 ± 3.3 mmHg), mean capillary P(O2) (16.7 ± 1.2 and 17.1 ± 1.6 mmHg), and peak perfusion during IE and WgT in Hyp, D(MO2) and leg V̇(O2) were 12 and 14% higher, respectively, during WgT than IE in Hyp (both P < 0.05). D(MO2) was insensitive to COHb (COHb: 0.7 vs. 7%, in IE Hyp and WgT Hyp). At exhaustion, the Y equilibration index was well above 1.0 in both conditions, reflecting greater convective than diffusive limitation to the O2 transfer in both Nx and Hyp. In conclusion, muscle V̇(O2) during sprint exercise is not limited by O2 delivery, O2 offloading from haemoglobin or structure-dependent diffusion constraints in the skeletal muscle. These findings reveal a remarkable functional reserve in muscle O2 diffusing capacity.

  2. 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.

  3. Diffuse myocardial fibrosis by T1-mapping in children with subclinical anthracycline cardiotoxicity: relationship to exercise capacity, cumulative dose and remodeling

    PubMed Central

    2013-01-01

    Background The late cardiotoxic effects of anthracycline chemotherapy influence morbidity and mortality in the growing population of childhood cancer survivors. Even with lower anthracycline doses, evidence of adverse cardiac remodeling and reduced exercise capacity exist. We aim to examine the relationship between cardiac structure, function and cardiovascular magnetic resonance (CMR) tissue characteristics with chemotherapy dose and exercise capacity in childhood cancer survivors. Methods Thirty patients (15 ± 3 years), at least 2 years following anthracycline treatment, underwent CMR, echocardiography, and cardiopulmonary exercise testing (peak VO2). CMR measured ventricular function, mass, T1 and T2 values, and myocardial extracellular volume fraction, ECV, a measure of diffuse fibrosis based on changes in myocardial T1 values pre- and post-gadolinium. Cardiac function was also assessed with conventional and speckle tracking echocardiography. Results Patients had normal LVEF (59 ± 7%) but peak VO2 was 17% lower than age-predicted normal values and were correlated with anthracycline dose (r = −0.49). Increased ECV correlated with decreased mass/volume ratio (r = −0.64), decreased LV wall thickness/height ratio (r = −0.72), lower peak VO2(r = −0.52), and higher cumulative dose (r = 0.40). Echocardiographic measures of systolic and diastolic function were reduced compared to normal values (p < 0.01), but had no relation to ECV, peak VO2 or cumulative dose. Conclusions Myocardial T1 and ECV were found to be early tissue markers of ventricular remodeling that may represent diffuse fibrosis in children with normal ejection fraction post anthracycline therapy, and are related to cumulative dose, exercise capacity and myocardial wall thinning. PMID:23758789

  4. (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)

  5. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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 carbon... employees shall be removed from the enclosed space if the carbon monoxide concentration exceeds a ceiling...

  6. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 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 carbon... employees shall be removed from the enclosed space if the carbon monoxide concentration exceeds a ceiling...

  7. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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 carbon... employees shall be removed from the enclosed space if the carbon monoxide concentration exceeds a ceiling...

  8. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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 carbon... employees shall be removed from the enclosed space if the carbon monoxide concentration exceeds a ceiling...

  9. 29 CFR 1917.24 - Carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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 carbon... employees shall be removed from the enclosed space if the carbon monoxide concentration exceeds a ceiling...

  10. 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

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

    2014-06-01

    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.

  11. 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)

  12. 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

  13. Self-diffusion nuclear magnetic resonance, microstructure transitions, and solubilization capacity of phytosterols and cholesterol in Winsor IV food-grade microemulsions.

    PubMed

    Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham; Hoffman, Roy E; Garti, Nissim

    2003-04-09

    Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phytosterols, cholesterol-lowering agents, in food products is of great interest to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12 times more than the dissolution capacity of the oil [R-(+)-limonene] for the same compounds. The solubilization capacity of phytosterols and cholesterol along a dilution line in a pseudo-ternary phase diagram [on this dilution line the weight ratio of R-(+)-limonene/ethanol/Tween 60 is constant at 1:1:3] was correlated to the microstructure transitions along the dilution line. Structural aspects were studied by self-diffusion NMR spectroscopy. The ability of phytosterols to compete with cholesterol for penetration into bile salt micelles in the gut may be limited to rich aqueous systems (O/W microemulsion).

  14. Effect of yoga practices on pulmonary function tests including transfer factor of lung for carbon monoxide (TLCO) in asthma patients.

    PubMed

    Singh, Savita; Soni, Ritu; Singh, K P; Tandon, O P

    2012-01-01

    Prana is the energy, when the self-energizing force embraces the body with extension and expansion and control, it is pranayama. It may affect the milieu at the bronchioles and the alveoli particularly at the alveolo-capillary membrane to facilitate diffusion and transport of gases. It may also increase oxygenation at tissue level. Aim of our study is to compare pulmonary functions and diffusion capacity in patients of bronchial asthma before and after yogic intervention of 2 months. Sixty stable asthmatic-patients were randomized into two groups i.e group 1 (Yoga training group) and group 2 (control group). Each group included thirty patients. Lung functions were recorded on all patients at baseline, and then after two months. Group 1 subjects showed a statistically significant improvement (P<0.001) in Transfer factor of the lung for carbon monoxide (TLCO), forced vital capacity (FVC), forced expiratory volume in 1st sec (FEV1), peak expiratory flow rate (PEFR), maximum voluntary ventilation (MVV) and slow vital capacity (SVC) after yoga practice. Quality of life also increased significantly. It was concluded that pranayama & yoga breathing and stretching postures are used to increase respiratory stamina, relax the chest muscles, expand the lungs, raise energy levels, and calm the body.

  15. 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

  16. Pharmacokinetics of perfluorobutane following intravenous bolus injection and continuous infusion of sonazoid in healthy volunteers and in patients with reduced pulmonary diffusing capacity.

    PubMed

    Landmark, Kristin Eitrem; Johansen, Per Wiik; Johnson, Judith A; Johansen, Bjørn; Uran, Steinar; Skotland, Tore

    2008-03-01

    The ultrasound contrast agent Sonazoidtrade mark was administered as an i.v. bolus injection of 0.6 microL microbubbles/kg body weight or as a continuous infusion over 30 min at a rate of 1.2 microL microbubbles/kg body weight to healthy volunteers and patients with reduced pulmonary diffusing capacity. Expired air and blood samples were collected from 32 subjects and perfluorobutane (PFB) gas was analyzed using validated gas chromatography mass spectrometry methods. Blood concentrations of PFB declined biphasicly with a distribution half-life (t(0.5 to 15)) of 2 to 3 min and an elimination half-life (t(15 to 120)) of 30 to 45 min. Area under the curve (AUC) values in patients with impaired gas diffusion were significantly larger than those in healthy volunteers. The exhalation kinetics were somewhat variable with a PFB elimination half-life (t(15 to 120)) of 28 to 111 min. Clearance of PFB was independent of study population and mode of administration. There were no deaths and no serious adverse events that resulted in the withdrawal of a subject from the study. With the exception that arthralgia predominated in healthy volunteers, healthy volunteers and diseased subjects did not show a different adverse event profile whether Sonazoid was administered as a bolus injection or as an infusion. Assessment of laboratory parameters (serum biochemistry, haematology and urinalysis), vital signs, oxygen saturation and electrocardiograms (ECGs) showed no changes which caused safety concern. (E-mail: Kristin.Landmark@ge.com).

  17. 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.

  18. 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.

  19. The Albuquerque carbon monoxide source apportionment study

    SciTech Connect

    Einfeld, W.

    1988-07-01

    At the request of the New Mexico Environmental Improvement Division, a study was carried out to examine, in detail, the relative contribution of various combustion sources to ambient carbon monoxide in Albuquerque during the winter season evening hours. The two-month field study (January--February 1985) included aerosol and gas monitoring at two sites in the Albuquerque area. Source contributions to ambient carbon monoxide were determined by regression techniques using tracer elements and by carbon isotope measurements on collected carbon monoxide. Results from isotopic carbon analysis of carbon monoxide show that, on average, mobile sources contributed 68 percent and wood burning sources 32 percent to ambient carbon monoxide levels during winter season evening hours. Good agreement was found between results from carbon isotope and linear regression techniques used to estimate average source strengths. The study results point to the significance of both mobile and residential wood burning sources as contributors to ambient carbon monoxide levels. 1 ref., 10 figs., 19 tabs.

  20. 40 CFR 52.1581 - 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—The September 28, 1995 revision to the carbon monoxide state... Quality Standard for carbon monoxide through the year 2007. (b) The base year carbon monoxide...

  1. 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...

  2. 40 CFR 52.1581 - 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—The September 28, 1995 revision to the carbon monoxide state... Quality Standard for carbon monoxide through the year 2007. (b) The base year carbon monoxide...

  3. 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...

  4. 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...

  5. 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...

  6. 40 CFR 52.1581 - 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—The September 28, 1995 revision to the carbon monoxide state... Quality Standard for carbon monoxide through the year 2007. (b) The base year carbon monoxide...

  7. 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...

  8. 40 CFR 52.1581 - 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—The September 28, 1995 revision to the carbon monoxide state... Quality Standard for carbon monoxide through the year 2007. (b) The base year carbon monoxide...

  9. 40 CFR 52.1581 - 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—The September 28, 1995 revision to the carbon monoxide state... Quality Standard for carbon monoxide through the year 2007. (b) The base year carbon monoxide...

  10. 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.

  11. Simultaneous measurements of capillary filtration and diffusion capacities during graded infusions of noradrenaline (NA) and 5-hydroxytryptamine (5-HT) into the rat hindquarter vascular bed.

    PubMed

    Rippe, B; Folkow, B

    1980-07-01

    The relationships between capillary diffusion capacity (PS) for Cr-EDTA respective capillary filtration capacity (CFC) and vascular resistance during graded intraarterial infusions of NA and 5-HT into the artificially constant flow perfused rat hindquarter vascular bed were investigated. During maximal vasodilatation PS for Cr-EDTA was some 5.5--5.7 ml/min x 100 g, CFC some 0.04 ml/min x mmHg x 100 g, while vascular resistance was 2.8 mmHg x ml-1 x min x 100 g (PRU100) and isogravimetric capillary pressure 12.8 mmHg on an average. Setting out from maximal vasodilatation, increasing doses of NA and 5-HT produced graded reductions in capillary surface area as reflected by progressive decreases in both PS for Cr-EDTA and CFC. These changes occurred simultaneously with progressive increases in both pre- and postcapillary resistances, causing elevations in both arterial and capillary hydrostatic pressures and hance in capillary fluid filtration at constant flow. Capillary hydrostatic pressure increased maximally to 45 mmHg (calculated for NA) and vascular resistance to some 21 mmHg x ml-1 x min x 100 g on an average. PS for Cr-EDTA decreased maximally to some 0.7--1 ml/min x 100 g for both NA and 5-HT and furthermore, the relationships between PS for Cr-EDTA and PRU100 for NA respective 5-HT were almost identical. This was taken to indicate that capillary surface area for nutritional exchange is affected similarly by both drugs. However, the CFU-PRU100 relationship was shifted towards some 30--50% higher CFC values for 5-HT than for NA at almost every level of vasoconstriction. This might suggest that 5-HT besides reducing capillary surface area also induced moderate increases in capillary permeability though increases in number and/or radius of large pores (gaps) (cf. Rippe, Kamiya & Folkow 1978). Even during NA-induced vasoconstriction, when virtually no changes in capillary permeability occurred, PS for Cr-EDTA was reduced to a relatively greater extent than CFC, the

  12. Environmental carbon monoxide related to pregnancy hypertension.

    PubMed

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

    2011-11-30

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

  13. 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.

  14. Mars - Microwave detection of carbon monoxide

    NASA Technical Reports Server (NTRS)

    Kakar, R. K.; Walters, J. W.; Wilson, W. J.

    1977-01-01

    The 115-gigahertz microwave line of carbon monoxide has been detected in the spectrum of Mars. The measurement is sensitive to carbon monoxide between the surface and an altitude of approximately 50 kilometers in the Martian atmosphere. This extends the altitude region to well above that previously sensed.

  15. 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.

  16. The Carbon Monoxide Tape Recorder

    NASA Technical Reports Server (NTRS)

    Schoeberl, M. R.; Duncan, B. N.; Douglass, A. R.; Waters, J.; Livesey, N.; Read, W.; Filipiak, M.

    2006-01-01

    Using Aura MLS data we have identified the stratospheric tape recorder in carbon monoxide (CO). Unlike the water vapor tape recorder, which is controlled by upper troposphere processes, the CO tape recorder is linked to seasonal biomass burning. Since CO has a lifetime of only a few months, the CO tape recorder barely extends above 20 km. The tape head for CO appears to be close to 360K near the same location as the water vapor tape head [Read et al, 20041. Both tape heads are below the equatorial cold point tropopause but above the base of the tropical tropopause layer. The tape recorder signal becomes more distinct from 360K to 380K suggesting that convective detrainment of plays a decreasingly important role with altitude. The Global Modeling Initiative chemical transport model forced by the climatology of biomass burning reproduces the CO tape recorder.

  17. 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.

  18. Engineering evidence for carbon monoxide toxicity cases.

    PubMed

    Galatsis, Kosmas

    2016-07-01

    Unintentional carbon monoxide poisonings and fatalities lead to many toxicity cases. Given the unusual physical properties of carbon monoxide-in that the gas is odorless and invisible-unorganized and erroneous methods in obtaining engineering evidence as required during the discovery process often occurs. Such evidence gathering spans domains that include building construction, appliance installation, industrial hygiene, mechanical engineering, combustion and physics. In this paper, we attempt to place a systematic framework that is relevant to key aspects in engineering evidence gathering for unintentional carbon monoxide poisoning cases. Such a framework aims to increase awareness of this process and relevant issues to help guide legal counsel and expert witnesses.

  19. 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.

  20. Conversion of carbon-containing materials to carbon monoxide

    SciTech Connect

    Davis, G. D.; Hill, J. C.; Mcminn, T. D.; Rooks, C. W.

    1981-06-09

    Carbon-containing materials are gasified to produce high purity carbon monoxide in a three zone unified system (Oxidizer, reducer and gasifier) using a metal oxide as the oxygen and heat source for the gasification with carbon monoxide. Carbon monoxide contacts the metal oxide prior to the gasification to release the oxygen and convert the carbon monoxide to carbon dioxide as the gasification medium.

  1. 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...

  2. 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....

  3. 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....

  4. 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...

  5. 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...

  6. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 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 monoxide... of this section, ethylene-carbon monoxide copolymers (CAS Reg. No. 25052-62-4) consist of the...

  7. 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....

  8. 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...

  9. 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....

  10. 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....

  11. 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....

  12. 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....

  13. 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....

  14. 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....

  15. 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...

  16. 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...

  17. 40 CFR 91.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 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...

  18. 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....

  19. 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.

  20. Aging Factsheets: Carbon Monoxide Poisoning Prevention

    EPA Pesticide Factsheets

    Everyone is at risk of being poisoned by carbon monoxide exposure. Older adults with pre-existing conditions, such as chronic heart disease, anemia, or respiratory problems, are even more susceptible to the effects of this odorless, colorless gas.

  1. A Fluorescent Source NDIR Carbon Monoxide Analyzer

    NASA Technical Reports Server (NTRS)

    Link, W. T.; McClatchie, E. A.; Watson, D. A.; Compher, A. B.

    1971-01-01

    This paper describes a new technique for measuring trace quantities of carbon monoxide by the nondispersive infrared (NDIR) methods. The technique uses the property of infrared fluorescence in a gas to generate a specific source of radiation which is an exact match of the absorption spectrum of the fundamental band of carbon monoxide. This results in an instrument with high sensitivity and specificity for CO. A novel method of referencing using an isotopic species of CO confers great stability on the instrument.

  2. 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.

  3. 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.

  4. 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.

  5. Developmental changes in mesophyll diffusion conductance and photosynthetic capacity under different light and water availabilities in Populus tremula: how structure constrains function.

    PubMed

    Tosens, Tiina; Niinemets, Ulo; Vislap, Vivian; Eichelmann, Hillar; Castro Díez, Pilar

    2012-05-01

    Finite mesophyll diffusion conductance (g(m) ) significantly constrains net assimilation rate (A(n) ), but g(m) variations and variation sources in response to environmental stresses during leaf development are imperfectly known. The combined effects of light and water limitations on g(m) and diffusion limitations of photosynthesis were studied in saplings of Populus tremula L. An one-dimensional diffusion model was used to gain insight into the importance of key anatomical traits in determining g(m) . Leaf development was associated with increases in dry mass per unit area, thickness, density, exposed mesophyll (S(mes) /S) and chloroplast (S(c) /S) to leaf area ratio, internal air space (f(ias) ), cell wall thickness and chloroplast dimensions. Development of S(mes) /S and S(c) /S was delayed under low light. Reduction in light availability was associated with lower S(c) /S, but with larger f(ias) and chloroplast thickness. Water stress reduced S(c) /S and increased cell wall thickness under high light. In all treatments, g(m) and A(n) increased and CO(2) drawdown because of g(m) , C(i) -C(c) , decreased with increasing leaf age. Low light and drought resulted in reduced g(m) and A(n) and increased C(i) -C(c) . These results emphasize the importance of g(m) and its components in determining A(n) variations during leaf development and in response to stress.

  6. [Carbon monoxide poisoning in children: never trivialize].

    PubMed

    Scalfaro, P; Haenggi, M H; Roulet, E; Gehri, M; Stucki, P; Schaller, M D; Cotting, J

    2000-03-01

    The risks linked to tissular hypoxemia after carbon monoxide (CO) poisoning are well known. Unawareness of CO exposure and of its complex pathophysiology may delay appropriate treatment and lead to long term neuropsychological sequelae. We report two cases of children treated in our institution and review the main issues regarding the optimal management. A high index of suspicion for carbon monoxide poisoning when dealing with an unclear neurological clinical presentation is mandatory. Classical therapy with normobaric 100% oxygen has to be instaured immediately. Hyperbaric oxygen therapy must be considered when anamnestic symptoms or clinical signs suggest neurological involvement even when carboxyhemoglobin values are low or already normalized.

  7. [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)

  8. 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 ...

  9. Graphite cloth facilitates vacuum evaporation of silicon monoxide

    NASA Technical Reports Server (NTRS)

    Carithers, M. D.

    1968-01-01

    Woven graphite cloth facilitates the vacuum deposition of thin films of silicon monoxide on substrate surfaces. The cloth serves both as a container and electric heating element for the silicon monoxide. It minimizes and prevents the silicon monoxide particle ejection, provides uniform heat distribution, and cools rapidly by radiation.

  10. 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...

  11. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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 carbon... introduction into service and annually thereafter, the NDIR carbon monoxide analyzer shall be checked...

  12. 40 CFR 52.1185 - 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—On November 24, 1994, the Michigan Department of Natural Resources submitted a revision to the carbon monoxide State Implementation Plan. The submittal pertained to a plan...

  13. 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...

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

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-carbon monoxide copolymers. 177.1312... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1312 Ethylene-carbon monoxide copolymers. The ethylene-carbon monoxide copolymers identified in paragraph (a) of this section may be...

  15. 40 CFR 52.349 - 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 Colorado § 52.349 Control strategy: Carbon monoxide. (a) Revisions to the Colorado State Implementation Plan, Carbon Monoxide Redesignation...

  16. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 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 monoxide copolymers. The ethylene-carbon monoxide copolymers identified in paragraph (a) of this section may be...

  17. 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...

  18. 40 CFR 52.1185 - 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—On November 24, 1994, the Michigan Department of Natural Resources submitted a revision to the carbon monoxide State Implementation Plan. The submittal pertained to a plan...

  19. 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...

  20. 75 FR 4815 - Integrated Science Assessment for Carbon Monoxide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-29

    ... AGENCY Integrated Science Assessment for Carbon Monoxide AGENCY: Environmental Protection Agency (EPA... availability of a final document titled, ``Integrated Science Assessment for Carbon Monoxide'' (EPA/600/R-09... standards (NAAQS) for carbon monoxide. DATES: The document will be available on January 29, 2010....

  1. 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...

  2. 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...

  3. 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)...

  4. 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...

  5. 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)...

  6. 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...

  7. 40 CFR 52.349 - 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 Colorado § 52.349 Control strategy: Carbon monoxide. (a) Revisions to the Colorado State Implementation Plan, Carbon Monoxide Redesignation...

  8. 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...

  9. 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...

  10. 40 CFR 52.1185 - 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—On November 24, 1994, the Michigan Department of Natural Resources submitted a revision to the carbon monoxide State Implementation Plan. The submittal pertained to a plan...

  11. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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 carbon... introduction into service and annually thereafter, the NDIR carbon monoxide analyzer shall be checked...

  12. 40 CFR 89.320 - 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... Test Equipment Provisions § 89.320 Carbon monoxide analyzer calibration. (a) Calibrate the NDIR carbon... introduction into service and annually thereafter, the NDIR carbon monoxide analyzer shall be checked...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 40 CFR 52.1887 - 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) 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...

  19. 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...

  20. 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...

  1. 40 CFR 52.1185 - 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—On November 24, 1994, the Michigan Department of Natural Resources submitted a revision to the carbon monoxide State Implementation Plan. The submittal pertained to a plan...

  2. 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...

  3. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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 carbon... introduction into service and annually thereafter, the NDIR carbon monoxide analyzer shall be checked...

  4. 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)...

  5. 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...

  6. 40 CFR 52.1185 - 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—On November 24, 1994, the Michigan Department of Natural Resources submitted a revision to the carbon monoxide State Implementation Plan. The submittal pertained to a plan...

  7. 40 CFR 52.349 - 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 Colorado § 52.349 Control strategy: Carbon monoxide. (a) Revisions to the Colorado State Implementation Plan, Carbon Monoxide Redesignation...

  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 52.349 - 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 Colorado § 52.349 Control strategy: Carbon monoxide. (a) Revisions to the Colorado State Implementation Plan, Carbon Monoxide Redesignation...

  10. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 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...

  11. 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...

  12. 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...) 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...

  13. 40 CFR 86.1322-84 - 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... Exhaust Test Procedures § 86.1322-84 Carbon monoxide analyzer calibration. The NDIR carbon monoxide... interference check. Prior to its introduction into service and annually thereafter, the NDIR carbon...

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

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 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 monoxide copolymers. The ethylene-carbon monoxide copolymers identified in paragraph (a) of this section may be...

  15. 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...

  16. 40 CFR 52.349 - 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 Colorado § 52.349 Control strategy: Carbon monoxide. (a) Revisions to the Colorado State Implementation Plan, Carbon Monoxide Redesignation...

  17. 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...

  18. 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...

  19. 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...

  20. 40 CFR 89.320 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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 carbon... introduction into service and annually thereafter, the NDIR carbon monoxide analyzer shall be checked...

  1. 21 CFR 177.1312 - Ethylene-carbon monoxide copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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 monoxide copolymers. The ethylene-carbon monoxide copolymers identified in paragraph (a) of this section may be...

  2. 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...

  3. 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.

  4. 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.

  5. Carbon Monoxide Metabolism in Roadside Soils

    PubMed Central

    Spratt, Henry G.; Hubbard, Jerry S.

    1981-01-01

    Air-dried soils which were equilibrated under relative humidities greater than 93% or moistened with liquid water showed marked increases in their capacities to oxidize CO to CO2. Liquid water addition in excess of saturation resulted in lower CO oxidation rates, reflecting the limited diffusion of CO through the aqueous phase. After 35 days' storage under 100% relative humidity, the capacity for CO oxidation decreased to 21% of the value observed with a freshly collected sample. Incubation of this stored soil under an atmosphere containing 200 ppm of CO (250 mg/m3) for 21 days resulted in a sevenfold increase in CO oxidation. A correlation was noted between the CO oxidative activity and the history of previous exposure of soils to high ambient levels of CO. The organisms responsible for CO oxidation apparently comprise a small fraction of the microbial population in the soils. With a roadside soil the oxidation of CO provided the driving force for the assimilation of CO2. The stoichiometry of the oxidative and assimilatory reactions in soil was in the range of values reported from laboratory studies with CO chemoautotrophs (carboxydobacteria). It is proposed that the population and activity of CO-oxidizing microorganisms increase in response to increasing levels of CO in the environment. PMID:16345770

  6. Removing Silicon Monoxide From Nickel Mirrors

    NASA Technical Reports Server (NTRS)

    Zaniewski, John J.

    1987-01-01

    Combination of polishing tool and polishing mixture used to remove adherent fragments of silicon monoxide protective coatings from nickel/aluminum mirrors without altering shapes or harming polishes of mirror surfaces. Polishing technique developed to prepare stained mirrors for recoating to restore high reflectance.

  7. 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…

  8. Neurological manifestation of carbon monoxide poisoning.

    PubMed Central

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

    1988-01-01

    The clinical signs and post-mortem findings in a case of carbon monoxide poisoning are described, and correlated with the computer tomographic (CT) scan appearances. The value of serial CT scanning as a diagnostic tool is highlighted. Images Figure 1 Figure 2 PMID:3174539

  9. 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.

  10. Contributions of distinct gold species to catalytic reactivity for carbon monoxide oxidation

    NASA Astrophysics Data System (ADS)

    Guo, Li-Wen; Du, Pei-Pei; Fu, Xin-Pu; Ma, Chao; Zeng, Jie; Si, Rui; Huang, Yu-Ying; Jia, Chun-Jiang; Zhang, Ya-Wen; Yan, Chun-Hua

    2016-11-01

    Small-size (<5 nm) gold nanostructures supported on reducible metal oxides have been widely investigated because of the unique catalytic properties they exhibit in diverse redox reactions. However, arguments about the nature of the gold active site have continued for two decades, due to the lack of comparable catalyst systems with specific gold species, as well as the scarcity of direct experimental evidence for the reaction mechanism under realistic working conditions. Here we report the determination of the contribution of single atoms, clusters and particles to the oxidation of carbon monoxide at room temperature, by the aid of in situ X-ray absorption fine structure analysis and in situ diffuse reflectance infrared Fourier transform spectroscopy. We find that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction.

  11. Contributions of distinct gold species to catalytic reactivity for carbon monoxide oxidation

    PubMed Central

    Guo, Li-Wen; Du, Pei-Pei; Fu, Xin-Pu; Ma, Chao; Zeng, Jie; Si, Rui; Huang, Yu-Ying; Jia, Chun-Jiang; Zhang, Ya-Wen; Yan, Chun-Hua

    2016-01-01

    Small-size (<5 nm) gold nanostructures supported on reducible metal oxides have been widely investigated because of the unique catalytic properties they exhibit in diverse redox reactions. However, arguments about the nature of the gold active site have continued for two decades, due to the lack of comparable catalyst systems with specific gold species, as well as the scarcity of direct experimental evidence for the reaction mechanism under realistic working conditions. Here we report the determination of the contribution of single atoms, clusters and particles to the oxidation of carbon monoxide at room temperature, by the aid of in situ X-ray absorption fine structure analysis and in situ diffuse reflectance infrared Fourier transform spectroscopy. We find that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction. PMID:27848964

  12. 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.

  13. 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.

  14. Effect of pattern and severity of respiratory muscle weakness on carbon monoxide gas transfer and lung volumes.

    PubMed

    Hart, N; Cramer, D; Ward, S P; Nickol, A H; Moxham, J; Polkey, M I; Pride, N B

    2002-10-01

    In clinical practice, an elevated carbon monoxide (CO) transfer coefficient (KCO) and restrictive ventilatory defect are taken as features of respiratory muscle weakness (RMW). However, the authors hypothesised that both pattern and severity of RMW effect gas transfer and lung volumes. Measurements of CO transfer and lung volumes were performed in patients with isolated diaphragm weakness (n=10), inspiratory muscle weakness (n=12), combined inspiratory and expiratory muscle weakness (n=5) and healthy controls (n=6). Patients with diaphragm weakness and inspiratory muscle weakness had reduced total lung capacity (TLC) (83.6% predicted and 68.9% pred, respectively), functional residual capacity (FRC) (83.9% pred and 83.6% pred) and transfer factor of the lung for CO (TL,CO) (86.2% pred and 66.2% pred) with increased KCO (114.1% pred and 130.2% pred). Patients with combined inspiratory and expiratory muscle weakness had reduced TLC (80.9% pred) but increased FRC (109.9% pred) and RV (157.4% pred) with decreased TL,CO (58.0% pred) and KCO (85.5% pred). In patients with diaphragm weakness, the increase in carbon monoxide transfer coefficient was similar to that of normal subjects when alveolar volume was reduced. However, the increase in carbon monoxide transfer coefficient in inspiratory muscle weakness was often less than expected, while in combined inspiratory and expiratory muscle weakness, the carbon monoxide transfer coefficient was normal/reduced despite further reductions in alveolar volume, which may indicate subtle abnormalities of the lung parenchyma or pulmonary vasculature. Thus, this study demonstrates the limitations of using carbon monoxide transfer coefficient in the diagnosis of respiratory muscle weakness, particularly if no account is taken of the alveolar volume at which the carbon monoxide transfer coefficient is made.

  15. The oxidation of carbon monoxide on polycrystalline rhodium under knudsen conditions. II. Reaction with nitrogen monoxide

    NASA Astrophysics Data System (ADS)

    Lintz, Hans-Günther; Weisker, Tilman

    1985-09-01

    The reaction between carbon monoxide and nitrogen monoxide on a polycrystalline rhodium ribbon under stationary conditions is followed by mass spectrometry. In the temperature range 300 to 1100 K the ratio of the partial pressures of the reactants varies between 0.1 < pNO/ pCO < 100 at values of the total pressure in the reactor from 10 -4 to 10 -5 Torr. The results can be interpreted qualitatively by a simple elementary reaction sequence. Simulation using literature values of the kinetic constants leads to semi-quantitative agreement with experimental results. No isothermal oscillations of the reaction rate could be observed under the stated conditions.

  16. Relationship between nutritional risk and exercise capacity in severe chronic obstructive pulmonary disease in male patients

    PubMed Central

    Shan, Xizheng; Liu, Jinming; Luo, Yanrong; Xu, Xiaowen; Han, Zhiqing; Li, Hailing

    2015-01-01

    Objective The nutritional status of chronic obstructive pulmonary disease (COPD) patients is associated with their exercise capacity. In the present study, we have explored the relationship between nutritional risk and exercise capacity in severe male COPD patients. Methods A total of 58 severe COPD male patients were enrolled in this study. The patients were assigned to no nutritional risk group (n=33) and nutritional risk group (n=25) according to the Nutritional Risk Screening (NRS, 2002) criteria. Blood gas analysis, conventional pulmonary function testing, and cardiopulmonary exercise testing were performed on all the patients. Results Results showed that the weight and BMI of the patients in the nutritional risk group were significantly lower than in the no nutritional risk group (P<0.05). The pulmonary diffusing capacity for carbon monoxide of the no nutritional risk group was significantly higher than that of the nutritional risk group (P<0.05). Besides, the peak VO2 (peak oxygen uptake), peak O2 pulse (peak oxygen pulse), and peak load of the nutritional risk group were significantly lower than those of the no nutritional risk group (P<0.05) and there were significantly negative correlations between the NRS score and peak VO2, peak O2 pulse, or peak load (r<0, P<0.05). Conclusion The association between exercise capacity and nutritional risk based on NRS 2002 in severe COPD male patients is supported by these results of this study. PMID:26150712

  17. 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

  18. 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.

  19. Accidental carbon monoxide poisoning in our homes.

    PubMed

    Sharma, Shruti; Gupta, Rahul; Paul, Barinder S; Puri, Sandeep; Garg, Shuchita

    2009-01-01

    Carbon monoxide (CO) is a colorless, odorless, tasteless, nonirritating, but significantly toxic gas. It is a product of combustion of organic matter in presence of insufficient oxygen supply. Symptoms of mild poisoning include headaches, vertigo and flu like effects, whereas larger exposures can lead to significant toxicity of the central nervous system (CNS), heart, and even death. We are reporting two cases that presented to us in the winter months of December to January with history, sign, symptoms, and radiological evidence of suspected CO poisoning.

  20. Myocardial function and perfusion in the CREST syndrome variant of progressive systemic sclerosis. Exercise radionuclide evaluation and comparison with diffuse scleroderma

    SciTech Connect

    Follansbee, W.P.; Curtiss, E.I.; Medsger, T.A. Jr.; Owens, G.R.; Steen, V.D.; Rodnan, G.P.

    1984-09-01

    Myocardial function and perfusion were evaluated in 22 patients with progressive systemic sclerosis with the CREST syndrome using exercise and radionuclide techniques, pulmonary function testing, and chest roentgenography. The results were compared with a similar study of 26 patients with progressive systemic sclerosis with diffuse scleroderma. The prevalence of thallium perfusion abnormalities was similar in the groups with CREST syndrome and diffuse scleroderma, (64 percent versus 77 percent), but the defects were significantly smaller in the CREST syndrome (p less than 0.01). Reperfusion thallium defects in the absence of extramural coronary artery disease were seen in 38 percent of patients with diffuse scleroderma. This finding was not seen in any of the patients with the CREST syndrome. In diffuse scleroderma, abnormalities of both right and left ventricular function were related to larger thallium perfusion defects. In the CREST syndrome, abnormalities of left ventricular function were minor, were seen only during exercise, and were unrelated to thallium perfusion defects. Abnormal resting right ventricular function was seen in 36 percent of the patients with the CREST syndrome and was associated with an isolated decrease in diffusing capacity of carbon monoxide. It is concluded that the cardiac manifestations of the CREST syndrome are distinct from those found in diffuse scleroderma. Unlike diffuse scleroderma, abnormalities of left ventricular function in the CREST syndrome are minor and are unrelated to abnormalities of coronary perfusion. Right ventricular dysfunction in the CREST syndrome appears to be primarily related to pulmonary vascular disease.

  1. Pulmonary vascular reserve and exercise capacity at sea level and at high altitude.

    PubMed

    Pavelescu, Adriana; Faoro, Vitalie; Guenard, Hervé; de Bisschop, Claire; Martinot, Jean-Benoit; Mélot, Christian; Naeije, Robert

    2013-03-01

    It has been suggested that increased pulmonary vascular reserve, as defined by reduced pulmonary vascular resistance (PVR) and increased pulmonary transit of agitated contrast measured by echocardiography, might be associated with increased exercise capacity. Thus, at altitude, where PVR is increased because of hypoxic vasoconstriction, a reduced pulmonary vascular reserve could contribute to reduced exercise capacity. Furthermore, a lower PVR could be associated with higher capillary blood volume and an increased lung diffusing capacity. We reviewed echocardiographic estimates of PVR and measurements of lung diffusing capacity for nitric oxide (DL(NO)) and for carbon monoxide (DL(CO)) at rest, and incremental cardiopulmonary exercise tests in 64 healthy subjects at sea level and during 4 different medical expeditions at altitudes around 5000 m. Altitude exposure was associated with a decrease in maximum oxygen uptake (VO2max), from 42±10 to 32±8 mL/min/kg and increases in PVR, ventilatory equivalents for CO2 (V(E)/VCO2), DL(NO), and DL(CO). By univariate linear regression VO2max at sea level and at altitude was associated with V(E)/VCO2 (p<0.001), mean pulmonary artery pressure (mPpa, p<0.05), stroke volume index (SVI, p<0.05), DL(NO) (p<0.02), and DL(CO) (p=0.05). By multivariable analysis, VO2max at sea level and at altitude was associated with V(E)/VCO2, mPpa, SVI, and DL(NO). The multivariable analysis also showed that the altitude-related decrease in VO2max was associated with increased PVR and V(E)/VCO2. These results suggest that pulmonary vascular reserve, defined by a combination of decreased PVR and increased DL(NO), allows for superior aerobic exercise capacity at a lower ventilatory cost, at sea level and at high altitude.

  2. 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.

  3. 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

  4. 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.

  5. The hydration structure of carbon monoxide by ab initio methods

    NASA Astrophysics Data System (ADS)

    Awoonor-Williams, Ernest; Rowley, Christopher N.

    2017-01-01

    The solvation of carbon monoxide (CO) in liquid water is important for understanding its toxicological effects and biochemical roles. In this paper, we use ab initio molecular dynamics (AIMD) and CCSD(T)-F12 calculations to assess the accuracy of the Straub and Karplus molecular mechanical (MM) model for CO(aq). The CCSD(T)-F12 CO-H2O potential energy surfaces show that the most stable structure corresponds to water donating a hydrogen bond to the C center. The MM-calculated surface incorrectly predicts that the O atom is a stronger hydrogen bond acceptor than the C atom. The AIMD simulations indicate that CO is solvated like a hydrophobic solute, with very limited hydrogen bonding with water. The MM model tends to overestimate the degree of hydrogen bonding and overestimates the atomic radius of the C atom. The calculated Gibbs energy of hydration using the TIP3P water model is in good agreement with the experiment (9.3 kJ mol-1 expt. vs 10.7 kJ mol-1 calc.). The calculated diffusivity of CO (aq) in TIP3P-model water was 5.1 ×10-5 cm2/s calc., more than double the experimental value of 2.3 ×10-5 cm2/s. The hydration energy calculated using the TIP4P-FB water model is in poorer agreement with the experiment (ΔG = 6.8 kJ/mol) but the diffusivity is in better agreement (D =2.5 ±0.1 ×10-5 cm2/s).

  6. 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.

  7. Integrated Science Assessment (ISA) for Carbon Monoxide ...

    EPA Pesticide Factsheets

    EPA announced the availability of the final report, Integrated Science Assessment (ISA) for Carbon Monoxide (CO). This report is EPA’s latest evaluation of the scientific literature on the potential human health and welfare effects associated with ambient exposures to CO. The development of this document is part of the Agency's periodic review of the national ambient air quality standards (NAAQS) for CO. The recently completed CO ISA and supplementary annexes, in conjunction with additional technical and policy assessments developed by EPA’s Office of Air and Radiation, will provide the scientific basis to inform EPA decisions related to the review of the current CO NAAQS. The integrated Plan for Review of the National Ambient Air Quality Standards for Carbon Monoxide (U.S. EPA, 2008, 193995) identifies key policy-relevant questions that provide a framework for this assessment of the scientific evidence. These questions frame the entire review of the NAAQS for CO and thus are informed by both science and policy considerations. The ISA organizes, presents, and integrates the scientific evidence which is considered along with findings from risk analyses and policy considerations to help the U.S. Environmental Protection Agency (EPA) address these questions during the NAAQS review.

  8. Carbon Monoxide Dehydrogenase Activity in Bradyrhizobium japonicum

    PubMed Central

    Lorite, María J.; Tachil, Jörg; Sanjuán, Juán; Meyer, Ortwin; Bedmar, Eulogio J.

    2000-01-01

    Bradyrhizobium japonicum strain 110spc4 was capable of chemolithoautotrophic growth with carbon monoxide (CO) as a sole energy and carbon source under aerobic conditions. The enzyme carbon monoxide dehydrogenase (CODH; EC 1.2.99.2) has been purified 21-fold, with a yield of 16% and a specific activity of 58 nmol of CO oxidized/min/mg of protein, by a procedure that involved differential ultracentrifugation, anion-exchange chromatography, hydrophobic interaction chromatography, and gel filtration. The purified enzyme gave a single protein and activity band on nondenaturing polyacrylamide gel electrophoresis and had a molecular mass of 230,000 Da. The 230-kDa enzyme was composed of large (L; 75-kDa), medium (M; 28.4-kDa), and small (S; 17.2-kDa) subunits occurring in heterohexameric (LMS)2 subunit composition. The 75-kDa polypeptide exhibited immunological cross-reactivity with the large subunit of the CODH of Oligotropha carboxidovorans. The B. japonicum enzyme contained, per mole, 2.29 atoms of Mo, 7.96 atoms of Fe, 7.60 atoms of labile S, and 1.99 mol of flavin. Treatment of the enzyme with iodoacetamide yielded di(carboxamidomethyl)molybdopterin cytosine dinucleotide, identifying molybdopterin cytosine dinucleotide as the organic portion of the B. japonicum CODH molybdenum cofactor. The absorption spectrum of the purified enzyme was characteristic of a molybdenum-containing iron-sulfur flavoprotein. PMID:10788353

  9. Carbon monoxide dehydrogenase activity in Bradyrhizobium japonicum.

    PubMed

    Lorite, M J; Tachil, J; Sanjuán, J; Meyer, O; Bedmar, E J

    2000-05-01

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

  10. 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.

  11. [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.

  12. Carbon monoxide metabolism by photosynthetic bacteria: Progress report

    SciTech Connect

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

    1988-01-01

    The photosynthetic bacterium, Rhodospirillum rubrum, is capable of converting carbon monoxide to CO/sub 2/ and cellular material. Because carbon monoxide is a major industrial pollutant in this country and a product of the biological oxidation of CO is the product of H/sub 2/, a major industrial feedstock, this process has practical importance. The oxidation of carbon monoxide to CO/sub 2/ by microorganisms is a major component of the carbon monoxide cycle on earth. We have isolated the enzyme responsible for this process from Rhodospirillum rubrum. Carbon monoxide dehydrogenase is an iron - sulfur, nickel- and zinc-containing enzyme. The enzyme is quite stable to heat and amendable to purification, however, it is very labile to oxygen, and all experiments must be conducted anaerobically. We are studying the activities of this enzyme, its regulation and its induction by its substrate carbon monoxide. The enzyme is absent in cells that have not been exposed to carbon monoxide, but cells produce the enzyme at a maximal rate upon exposure to carbon monoxide for as little as ten minutes. Oxygen, a potent and irreversible inhibitor of the enzyme, represses the synthesis of this enzyme. 1 tab.

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  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 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...

  19. 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...

  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 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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,...

  6. 40 CFR 52.729 - 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 Illinois> § 52.729 Control strategy: Carbon..., Illinois be granted a carbon monoxide (CO) state implementation plan (SIP) revision with...

  7. 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...

  8. 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...

  9. 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,...

  10. 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,...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 40 CFR 52.376 - 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 Connecticut § 52.376 Control strategy: Carbon... submitted a revision to the carbon monoxide State Implementation Plan for the 1990 base year...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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,...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 40 CFR 52.729 - 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 Illinois> § 52.729 Control strategy: Carbon..., Illinois be granted a carbon monoxide (CO) state implementation plan (SIP) revision with...

  7. 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...

  8. 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.

  9. 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)

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Integrated Science Assessment (ISA) for Carbon Monoxide ...

    EPA Pesticide Factsheets

    EPA announced that the First External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes was made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA's decision regarding whether the current standards for CO sufficiently protect public health and the environment. The Integrated Plan for Review of the NAAQS for CO {U.S. EPA, 2008 #8615} identifies key policy-relevant questions that provide a framework for this review of the scientific evidence. These questions frame the entire review of the NAAQS, and thus are informed by both science and policy considerations. The ISA organizes and presents the scientific evidence such that it, when considered along with findings from risk analyses and policy considerations, will help the EPA address these questions during the NAAQS review:

  16. 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)

  17. 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.

  18. 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).

  19. 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.

  20. Membrane and Capillary Components of Lung Diffusion in Infants with Bronchopulmonary Dysplasia

    PubMed Central

    Chang, Daniel V.; Assaf, Santiago J.; Tiller, Christina J.; Kisling, Jeffrey A.

    2016-01-01

    Rationale: Autopsied lungs of infants with bronchopulmonary dysplasia (BPD) demonstrate impaired alveolar development with larger and fewer alveoli, which is consistent with our previous physiologic findings of lower pulmonary diffusing capacity of the lung for carbon monoxide (DlCO) in infants and toddlers with BPD compared with healthy controls born at full term (FT). However, it is not known whether the decreased DlCO in infants with BPD results from a reduction in both components of DlCO: pulmonary membrane diffusing capacity (Dm) and Vc. Objectives: We hypothesized that impairment of alveolar development in BPD results in a decrease in both Dm and Vc components of DlCO but that the Dm/Vc ratio would not differ between the BPD and FT groups. Methods: DlCO was measured under conditions of room air and high inspired oxygen (90%), which enabled Dm and Vc to be calculated. Measurements and Main Results: Dm and Vc increased with increasing body length; however, infants with BPD had significantly lower Dm and Vc than FT subjects after adjustment for race, sex, body length, and corrected age. In contrast to Dm and Vc, the Dm/Vc ratio remained constant with increasing body length and did not differ for infants with BPD and FT subjects. Conclusions: Our findings are consistent with infants with BPD having impaired alveolar development with fewer but larger alveoli, as well as a reduced Vc. PMID:26566056

  1. Carbon monoxide poisoning in the United Arab Emirates.

    PubMed

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

    2011-01-01

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

  2. 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.

  3. 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)

  4. Carbon Monoxide | Air Quality Planning Unit | Ground-level ...

    EPA Pesticide Factsheets

    2017-04-10

    Carbon monoxide (CO) is a colorless, odorless gas that can increase the severity of lung ailments, cause dizziness, fatigue, nausea, and even death. EPA has defined the national ambient air quality standard (NAAQS) for carbon monoxide as nine parts per million averaged over an eight-hour period, and this threshold cannot be exceeded more than once a year or an area would be violating the standard.

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

    SciTech Connect

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

  6. 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.

  7. Vehicle occupant exposure to carbon monoxide.

    PubMed

    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.

  8. Integrated Science Assessment (ISA) for Carbon Monoxide ...

    EPA Pesticide Factsheets

    EPA announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes was made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA's decision regarding whether the current standards for CO sufficiently protect public health and the environment. Section 108(a) of the Clean Air Act directs the EPA Administrator to identify certain pollutants that “cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare” and to issue air quality criteria for them. These air quality criteria are to “accurately reflect the latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on public health or welfare which may be expected from the presence of such pollutant in the ambient air….” Under section 109 of the Act, EPA is to establish national ambient air quality standards (NAAQS) for each pollutant for which EPA has issued criteria. Section 109(d) of the Act requires periodic review and, if appropriate, revision of existing air quality criteria to reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. EPA is also to revise the NAAQS, if appropriate, based on the revised air quality criteria.

  9. 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).

  10. 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.

  11. Chlorine Monoxide in the Antarctic Spring Stratosphere.

    NASA Astrophysics Data System (ADS)

    Jaramillo-Ayerbe, Mauricio

    1988-06-01

    A series of observations of stratospheric chlorine monoxide (ClO) were carried out during the austral springs of 1986 and 1987 in McMurdo Station, Antarctica, as part of two experimental campaigns sent to investigate the seasonal decrease in ozone over the antarctic continent (the ozone "hole"). Measurements of the vertical distribution of ClO were obtained by high resolution ground-based emission spectroscopy at 278 GHz, using the Stony Brook mm-wave receiver. They show the presence of an anomalous layer of lower stratospheric ClO which is not observed at other latitudes. This anomalous layer is centered at ~20 km altitude and exhibits a pronounced diurnal variation, reaching a maximum at midday and disappearing at night. During the period of Sep. 20-24, 1987, the lower-stratospheric ClO had a maximum volume mixing ratio of 1.8_sp{+0cdot5}{ -0cdot9} ppbv. A normal ClO layer centered at ~36 km was also observed, with concentrations and diurnal behavior similar to those seen in tropical latitudes. These findings are evidence of anomalous chlorine chemistry taking place in the lower stratosphere during the antarctic spring, and indicate that increasing anthropogenic chlorine is a prime causative agent in the formation of the ozone hole.

  12. Overabundance of carbon monoxide in calorimetry tests

    SciTech Connect

    Ree, F.H.; Pitz, W.J.; Thiel, M. van; Souers, P.C.

    1996-04-04

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

  13. Carbon monoxide studies at high altitude.

    PubMed

    McGrath, J J

    1988-01-01

    In high altitude areas, ambient carbon monoxide (CO) concentrations are rising because of the increasing number of new residents and tourists, and their concomitant use of motor vehicles and heating appliances. There are, however, comparatively few studies of the acute or chronic physiological effects that may be caused by inhaling CO at high altitude. There are data supporting the concept that the effects of breathing CO at high altitude are additive, and data suggesting that the effects may be more than additive. Visual sensitivity and flicker fusion frequency are reduced in humans inhaling CO at high altitude. One provocative study suggests that the increase in coronary capillarity seen with chronic altitude exposure may be blocked by CO. We exposed male, laboratory rats for 6 weeks to 100 ppm CO, 4676 m (15,000 ft) simulated high altitude (SHA), and CO at SHA. SHA increase hematocrit ratio (Hct) and right ventricle weight, but decreased body weight. CO increased Hct and left ventricle weight. Our results indicate that 100 ppm CO does not exacerbate the effects produced by exposure to 4676 m altitude.

  14. 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.

  15. Carbon monoxide and anesthesia-induced neurotoxicity☆

    PubMed Central

    Levy, Richard J.

    2016-01-01

    The majority of commonly used anesthetic agents induce widespread neuronal degeneration in the developing mammalian brain. Downstream, the process appears to involve activation of the oxidative stress-associated mitochondrial apoptosis pathway. Targeting this pathway could result in prevention of anesthetic toxicity in the immature brain. Carbon monoxide (CO) is a gas that exerts biological activity in the developing brain and low dose exposures have the potential to provide neuroprotection. In recent work, low concentration CO exposures limited isoflurane-induced neuronal apoptosis in a dose-dependent manner in newborn mice and modulated oxidative stress within forebrain mitochondria. Because infants and children are routinely exposed to low levels of CO during low-flow general endotracheal anesthesia, such anti-oxidant and pro-survival cellular effects are clinically relevant. Here we provide an overview of anesthesia-related CO exposure, discuss the biological activity of low concentration CO, detail the effects of CO in the brain during development, and provide evidence for CO-mediated inhibition of anesthesia-induced neurotoxicity. PMID:27616667

  16. 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.

  17. Carbon monoxide. Toxic gas and fuel for anaerobes and aerobes: carbon monoxide dehydrogenases.

    PubMed

    Jeoung, Jae-Hun; Fesseler, Jochen; Goetzl, Sebastian; Dobbek, Holger

    2014-01-01

    Carbon monoxide (CO) pollutes the atmosphere and is toxic for respiring organisms including man. But CO is also an energy and carbon source for phylogenetically diverse microbes living under aerobic and anaerobic conditions. Use of CO as metabolic fuel for microbes relies on enzymes like carbon monoxide dehydrogenase (CODH) and acetyl-CoA synthase (ACS), which catalyze conversions resembling processes that eventually initiated the dawn of life.CODHs catalyze the (reversible) oxidation of CO with water to CO2 and come in two different flavors with unprecedented active site architectures. Aerobic bacteria employ a Cu- and Mo-containing CODH in which Cu activates CO and Mo activates water and takes up the two electrons generated in the reaction. Anaerobic bacteria and archaea use a Ni- and Fe-containing CODH, where Ni activates CO and Fe provides the nucleophilic water. Ni- and Fe-containing CODHs are frequently associated with ACS, where the CODH component reduces CO2 to CO and ACS condenses CO with a methyl group and CoA to acetyl-CoA.Our current state of knowledge on how the three enzymes catalyze these reactions will be summarized and the different strategies of CODHs to achieve the same task within different active site architectures compared.

  18. The Carbon Monoxide Dehydrogenase from Desulfovibrio vulgaris.

    PubMed

    Hadj-Saïd, Jessica; Pandelia, Maria-Eirini; Léger, Christophe; Fourmond, Vincent; Dementin, Sébastien

    2015-12-01

    Ni-containing Carbon Monoxide Dehydrogenases (CODHs) catalyze the reversible conversion between CO and CO₂and are involved in energy conservation and carbon fixation. These homodimeric enzymes house two NiFeS active sites (C-clusters) and three accessory [4Fe-4S] clusters. The Desulfovibrio vulgaris (Dv) genome contains a two-gene CODH operon coding for a CODH (cooS) and a maturation protein (cooC) involved in nickel insertion in the active site. According to the literature, the question of the precise function of CooC as a chaperone folding the C-cluster in a form which accommodates free nickel or as a mere nickel donor is not resolved. Here, we report the biochemical and spectroscopic characterization of two recombinant forms of the CODH, produced in the absence and in the presence of CooC, designated CooS and CooS(C), respectively. CooS contains no nickel and cannot be activated, supporting the idea that the role of CooC is to fold the C-cluster so that it can bind nickel. As expected, CooS(C) is Ni-loaded, reversibly converts CO and CO₂, displays the typical Cred1 and Cred2 EPR signatures of the C-cluster and activates in the presence of methyl viologen and CO in an autocatalytic process. However, Ni-loaded CooS(C) reaches maximum activity only upon reductive treatment in the presence of exogenous nickel, a phenomenon that had not been observed before. Surprisingly, the enzyme displays the Cred1 and Cred2 signatures whether it has been activated or not, showing that this activation process of the Ni-loaded Dv CODH is not associated with structural changes at the active site.

  19. Pulmonary vascular stress from carbon monoxide.

    PubMed

    Thom, S R; Ohnishi, S T; Fisher, D; Xu, Y A; Ischiropoulos, H

    1999-01-01

    Studies were conducted with rats to investigate whether exposure to carbon monoxide (CO) at concentrations frequently found in the environment caused lung injury mediated by nitric oxide (*NO)-derived oxidants. Lung capillary leakage was significantly increased 18 h after rats had been exposed to CO at concentrations of 50 ppm or more for 1 h. An elevation of *NO during CO exposure was demonstrated by electron paramagnetic resonance spectroscopy. There was a 2.6-fold increase of *NO over control in the lungs of rats exposed to 100 ppm CO. A qualitative increase in the concentration of H2O2 was also detected in lungs during CO exposure, and this change was caused by *NO as it was inhibited in rats pretreated with the nitric oxide synthase inhibitor, Nomega nitro-l-arginine methyl ester (l-NAME). Production of *NO-derived oxidants during CO exposure was indicated by an elevated concentration of nitrotyrosine in lung homogenates. The CO-associated elevations in lung capillary leakage and nitrotyrosine concentration did not occur when rats were pretreated with l-NAME. CO exposure did not change the concentrations of endothelial or inducible nitric oxide synthase in lung and leukocyte sequestration was not detected as a consequence of CO exposure. CO-mediated lung leak and nitrotyrosine elevation were not affected by neutropenia. We conclude that CO exposure elevates the steady-state concentration of *NO in lungs. Consequences from this change include increases in the concentration of reactive oxygen species, production of *NO-derived oxidants such as peroxynitrite, and physiological evidence of lung injury.

  20. Pulmonary Phototherapy for Treating Carbon Monoxide Poisoning

    PubMed Central

    Zazzeron, Luca; Liu, Chen; Franco, Walfre; Nakagawa, Akito; Farinelli, William A.; Bloch, Donald B.; Anderson, R. Rox

    2015-01-01

    Rationale: Carbon monoxide (CO) exposure is a leading cause of poison-related mortality. CO binds to Hb, forming carboxyhemoglobin (COHb), and produces tissue damage. Treatment of CO poisoning requires rapid removal of CO and restoration of oxygen delivery. Visible light is known to effectively dissociate CO from Hb, with a single photon dissociating one CO molecule. Objectives: To determine whether illumination of the lungs of CO-poisoned mice causes dissociation of COHb from blood transiting the lungs, releasing CO into alveoli and thereby enhancing the rate of CO elimination. Methods: We developed a model of CO poisoning in anesthetized and mechanically ventilated mice to assess the effects of direct lung illumination (phototherapy) on the CO elimination rate. Light at wavelengths between 532 and 690 nm was tested. The effect of lung phototherapy administered during CO poisoning was also studied. To avoid a thoracotomy, we assessed the effect of lung phototherapy delivered to murine lungs via an optical fiber placed in the esophagus. Measurements and Main Results: In CO-poisoned mice, phototherapy of exposed lungs at 532, 570, 592, and 628 nm dissociated CO from Hb and doubled the CO elimination rate. Phototherapy administered during severe CO poisoning limited the blood COHb increase and improved the survival rate. Noninvasive transesophageal phototherapy delivered to murine lungs via an optical fiber increased the rate of CO elimination while avoiding a thoracotomy. Conclusions: Future development and scaling up of lung phototherapy for patients with CO exposure may provide a significant advance for treating and preventing CO poisoning. PMID:26214119

  1. 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.

  2. 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.

  3. 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

  4. Interstitial lung disease increases mortality in systemic sclerosis patients with pulmonary arterial hypertension without affecting hemodynamics and exercise capacity.

    PubMed

    Michelfelder, M; Becker, M; Riedlinger, A; Siegert, E; Drömann, D; Yu, X; Petersen, F; Riemekasten, G

    2017-02-01

    Published data suggest that coexisting interstitial lung disease (ILD) has an impact on mortality in patients with systemic sclerosis (SSc) and pulmonary arterial hypertension (PAH), but there is scarce knowledge if this is reflected by hemodynamics, exercise capacity, autoantibody profile, or pulmonary function. In this partially retrospective study, 27 SSc-PAH patients were compared to 24 SSc-PAH patients with coexisting ILD respecting to survival, pulmonary function, hemodynamics, exercise capacity, and laboratory parameters. Survival was significantly worse in SSc-PAH-ILD patients than in SSc patients with isolated PAH (1, 5, and 10-year survival rates 86, 54, and 54% versus 96, 92, and 82%, p = 0.013). Compared to isolated SSc-PAH patients, patients with SSc-PAH-ILD revealed lower forced expiratory volume after 1 s (FEV1) values at the time of PAH diagnosis as well as 1 and 2 years later (p = 0.002) without significant decrease in the PAH course in both groups. At PAH diagnosis, diffusion capacity for carbon monoxide (DLCO) values were lower in the ILD-PAH group. Coexisting ILD was not associated with lower exercise capacity, different FEV1/forced vital capacity (FVC) ratio, higher WHO functional class, or reduced hemodynamics. Higher levels of antibodies against angiotensin and endothelin receptors predict mortality in all SSc-PAH patients but could not differentiate between PAH patients with and without ILD. Our study confirmed an impact of ILD on mortality in SSc-PAH patients. Pulmonary function parameters can be used to distinguish PAH from PAH-ILD. The higher mortality rate cannot be explained by differences in hemodynamics, exercise capacity, or autoantibody levels. Mechanisms of mortality remain to be studied.

  5. 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)

  6. Lithium-free transition metal monoxides for positive electrodes in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Jung, Sung-Kyun; Kim, Hyunchul; Cho, Min Gee; Cho, Sung-Pyo; Lee, Byungju; Kim, Hyungsub; Park, Young-Uk; Hong, Jihyun; Park, Kyu-Young; Yoon, Gabin; Seong, Won Mo; Cho, Yongbeom; Oh, Myoung Hwan; Kim, Haegyeom; Gwon, Hyeokjo; Hwang, Insang; Hyeon, Taeghwan; Yoon, Won-Sub; Kang, Kisuk

    2017-01-01

    Lithium-ion batteries based on intercalation compounds have dominated the advanced portable energy storage market. The positive electrode materials in these batteries belong to a material group of lithium-conducting crystals that contain redox-active transition metal and lithium. Materials without lithium-conducting paths or lithium-free compounds could be rarely used as positive electrodes due to the incapability of reversible lithium intercalation or the necessity of using metallic lithium as negative electrodes. These constraints have significantly limited the choice of materials and retarded the development of new positive electrodes in lithium-ion batteries. Here, we demonstrate that lithium-free transition metal monoxides that do not contain lithium-conducting paths in their crystal structure can be converted into high-capacity positive electrodes in the electrochemical cell by initially decorating the monoxide surface with nanosized lithium fluoride. This unusual electrochemical behaviour is attributed to a surface conversion reaction mechanism in contrast with the classic lithium intercalation reaction. Our findings will offer a potential new path in the design of positive electrode materials in lithium-ion batteries.

  7. 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

  8. Mental capacity.

    PubMed

    Williams, Ruth

    2010-02-03

    Three short videos exploring some of the different principles in the Mental Capacity Act 2009 are available on Social Care TV, an online channel intended mainly for the social care sector, although the films are relevant to any professionals whose work is affected by the act. The dramas, which are set in a residential home, a person's own home and a residential school for young people with learning difficulties, concern thedecision-making process and can be viewed at www.scie.org.uk/socialcaretv/topic.asp?guid=377dbe1b-de0c-4d66-bb87-22a243542db2.

  9. 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.

  10. 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.

  11. Carbon monoxide metabolism by the photosynthetic bacterium Rhodospirillum rubrum

    SciTech Connect

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

    1991-01-01

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

  12. 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.

  13. Early white matter injuries in patients with acute carbon monoxide intoxication

    PubMed Central

    Tsai, Ping-Huei; Chou, Ming-Chung; Chiang, Shih-Wei; Chung, Hsiao-Wen; Liu, Hua-Shan; Kao, Hung-Wen; Chen, Cheng-Yu

    2017-01-01

    Abstract Evaluation of acute white matter injuries caused by carbon monoxide (CO) poisoning can be limited by conventional magnetic resonance (MR) imaging. We aim to evaluate the feasibility of diffusion kurtosis imaging (DKI) for early detection of white matter alterations in patients with acute CO intoxication. A total of 30 subjects including 15 acute CO patients and 15 age- and sex-matched healthy volunteers were enrolled in this study. MR examinations were performed on a 3T MR scanner within 8 days after CO intoxication. DKI data were acquired to derive axial, radial, and mean kurtosis, as well as fractional anisotropy (FA), axial, radial, and mean diffusivity for tract-specific comparisons between the 2 groups. Significant decreases of mean kurtosis were shown in the genu of corpus callosum, cingulum, and motor-related tracts (corticospinal and corticobulbar tracts) in patients with acute CO intoxication as compared with controls. On the contrary, significant differences of FA values were merely shown in the regions of corticospinal tracts. DKI demonstrated comparably stronger potential than diffusion tensor imaging in terms of early detection of white matter changes in patients with acute CO intoxication. This may have implications in therapeutic strategy for managing acute CO intoxication patients. PMID:28151889

  14. Griffith diffusers

    NASA Technical Reports Server (NTRS)

    Yang, T.-T.; Nelson, C. D.

    1979-01-01

    Contoured wall diffusers are designed by using an inverse method. The prescribed wall velocity distribution(s) was taken from the high lift airfoil designed by A. A. Griffith in 1938; therefore, such diffusers are named Griffith diffusers. First the formulation of the inverse problem and the method of solution are outlined. Then the typical contour of a two-dimensional diffuser and velocity distributions across the flow channel at various stations are presented. For a Griffith diffuser to operate as it is designed, boundary layer suction is necessary. Discussion of the percentage of through-flow required to be removed for the purpose of boundary layer control is given. Finally, reference is made to the latest version of a computer program for a two-dimensional diffuser requiring only area ratio, nondimensional length and suction percentage as inputs.

  15. 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...

  16. 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....

  17. 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...

  18. 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....

  19. 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...

  20. 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...

  1. 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....

  2. 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...

  3. 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....

  4. 40 CFR Appendix A - Protocol for Using an Electrochemical Analyzer to Determine Oxygen and Carbon Monoxide...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Analyzer to Determine Oxygen and Carbon Monoxide Concentrations From Certain Engines A Appendix A...—Protocol for Using an Electrochemical Analyzer to Determine Oxygen and Carbon Monoxide Concentrations From... portable electrochemical (EC) cells for measuring carbon monoxide (CO) and oxygen (O2) concentrations...

  5. 40 CFR Appendix A - Protocol for Using an Electrochemical Analyzer to Determine Oxygen and Carbon Monoxide...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Analyzer to Determine Oxygen and Carbon Monoxide Concentrations From Certain Engines A Appendix A...—Protocol for Using an Electrochemical Analyzer to Determine Oxygen and Carbon Monoxide Concentrations From... portable electrochemical (EC) cells for measuring carbon monoxide (CO) and oxygen (O2) concentrations...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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.

  14. Carbon monoxide detector. [electrochemical gas detector for spacecraft use

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

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

  15. 2010 Final Assessment: Integrated Science Assessment for Carbon Monoxide

    EPA Science Inventory

    EPA released the final Integrated Science Assessment (ISA) for Carbon Monoxide (CO). This is EPA’s latest evaluation of the scientific literature on the potential human health and welfare effects associated with ambient exposures to CO. The development of this document i...

  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. 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...

  18. 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...

  19. 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…

  20. Carbon Monoxide Isotopes: On the Trail of Galactic Chemical Evolution

    NASA Technical Reports Server (NTRS)

    Langer, W.

    1995-01-01

    From the early days of the discovery of radio emission from carbon monoxide it was realized that it offered unusual potential for under- standing the chemical evolution of the Galaxy and external galaxies through measurements of molecular isotopes. These results bear on stellar nucleosynthesis, star formation, and gases in the interstellar medium. Progress in isotopic radio measurements will be reviewed.

  1. 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...

  2. 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...

  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. Some usual and unusual poisonings due to carbon monoxide.

    PubMed

    Kaye, Sidney

    2003-01-01

    Carbon monoxide poisoning is a frequent occurrence in both developed and under developed countries of the world. Carbon monoxide can be produced in fires, automobile engine exhausts and the incomplete combustion of organic matter. It is a "silent killer" that initially produces a mild progressive frontal headache, drowsiness and sleep that is usually ignored as common place. Continued low-level CO exposure for a long period of time in a confined space is cumulative and these accidental deaths are frequent but should be avoidable. Several usual and unusual poisonings are reported to illustrate its various forms of exposure. It all began many years ago when a bolt of lightening hit a fallen tree and produced a fire. Early cave man later learned to enjoy some of the benefits of this new discovery. They could now see at night, they could keep warm, keep the predators at bay, cook their food and make it taste better and be more gentle to their teeth. Also meat could be preserved and eaten at a later date especially if it were dried and smoked. They learned by trial and error that it was dangerous to bring their fire deep into their cave without a chimney. Carbon monoxide (CO) also can be easily produced by many other sources besides fire. Very common today is the incomplete combustion of gasoline in the engine of an automobile which can produce about 6% carbon monoxide.

  6. 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...

  7. 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.

  8. Carbon Monoxide Poisoning - Multiple Languages: MedlinePlus

    MedlinePlus

    ... on this page, please enable JavaScript. Amharic (amarunya) Arabic (العربية) Chinese - Traditional (繁體中文) French (français) German (Deutsch) ... Amharic) PDF Centers for Disease Control and Prevention Arabic (العربية) Carbon Monoxide Poisoning English (Arabic) العربية PDF ...

  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. 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 ...

  11. 40 CFR 86.1322-84 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (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...

  12. 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...

  13. 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...

  14. 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.

  15. 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.

  16. Computer simulations studies of the catalytic oxidation of carbon monoxide on platinum metals

    NASA Astrophysics Data System (ADS)

    Kaukonen, H.-P.; Nieminen, R. M.

    1989-10-01

    The steady-state catalytic oxidation process of carbon monoxide on platinum metal surfaces is studied using two irreversible kinetic computer simulation models: (a) An extended version of the model introduced by Ziff, Gulari, and Barshad (ZGB) with the effects of CO desorption and diffusion as well as finite reaction probability taken into account. The different physical processes, diffusion and desorption are studied independently and their effect on the equilibrium window, i.e., the regime where steady CO2 formation occurs is determined. (b) An interaction model where adatom-adatom nearest-neighbor (nn) interactions are taken explicitly into account through Boltzmann terms J1, J2, and J3 which are the energies of the CO-CO, O-O, and CO-O interactions, respectively. The phase diagrams in the temperature-CO-partial pressure (T,pCO-) plane are determined for different values of the nn interactions. The behavior of the system is dependent on the sign of J1(=J2 in the simulations) as well as the sign of the difference J1-J3. There is thus a clear analogy with a two-component equilibrium lattice gas with nn interactions.

  17. 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

  18. Computer simulations of carbon monoxide photodissociation in myoglobin: structural interpretation of the B states.

    PubMed Central

    Meller, J; Elber, R

    1998-01-01

    The early diffusion processes of a photodissociated ligand (carbon monoxide) in sperm whale myoglobin and its Phe29 mutant are studied computationally. An explicit solvent model is employed in which the protein is embedded in a box of at least 2300 water molecules. Electrostatic interactions are accounted for by using the particle mesh Ewald. Two hundred seventy molecular dynamics trajectories are computed for 10 ps. Different models of solvation and the ligand, and their influence on the diffusion are examined. The two B states of the CO are identified as "docking" sites in the heme pocket. The sites have a similar angle with respect to the heme normal, but differ in the orientation in the plane. The computational detection of the B states is stable under a reasonable variation of simulation conditions. However, in some trajectories only one of the states is observed. It is therefore necessary to use extensive simulation data to probe these states. Comparison to diffraction experiments and spectroscopy is performed. The shape of the experimental infrared spectra is computed. The overall linewidth is in an agreement with experiment. The contributions to the linewidth (van der Waals and electrostatic interactions) are discussed. PMID:9533692

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

    PubMed

    Cukor, Jeffrey; Restuccia, Marc

    2007-10-01

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

  20. 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.

  1. 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.

  2. 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.

  3. Retrograde amnesia following carbon monoxide poisoning: a case report.

    PubMed

    Acland, Peter R; Heaver, Catriona

    2008-07-01

    Retrograde amnesia is a recognised neurological complication of carbon monoxide poisoning. This article describes the case of a female found dead in her bath where initial post-mortem findings and the surrounding circumstances raised strong suspicions of homicide, especially when there was contradictory evidence from her husband who was the only other person present. He was later diagnosed as having retrograde amnesia between his two visits to the bathroom to attend to his wife which caused him to merge them into one event, thus arousing suspicions of foul play. The discussion explores the current clinical views on non-fatal carbon monoxide poisoning as well as problems of interpretation of information derived from case work.

  4. 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.

  5. Ab initio simulations of liquid carbon monoxide at high pressure

    NASA Astrophysics Data System (ADS)

    Leonhardi, Tanis C.; Militzer, Burkhard

    2017-03-01

    Carbon monoxide occurs as a volatile species in the interiors of terrestrial planets, and as a disequilibrium atmospheric constituent in the giant planets. It plays an important role during the accretionary stages of planet formation reacting with gases to form compounds such as CH4 and H2O. The structure of carbon monoxide is unknown over the majority of the temperature and pressure regime in giant planet interiors. Here we perform ab initio molecular dynamics simulations to characterize CO to 140 GPa and 5,000 K. We find that CO is stable as a molecular liquid at lower P-T conditions, as a polymeric liquid at higher P-T conditions found in ice giant interiors, and as a plasma at high-T.

  6. 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

  7. 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.

  8. 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.

  9. Measurement of Strontium Monoxide in Methane-Air Flames.

    PubMed

    Wimberly, Bobby J; Hornkohl, James O; Parigger, Christian G

    2017-02-01

    The spectroscopy of alkaline earth metal compounds is stimulated by the use of these compounds in practical areas ranging from technology to medicine. Applications in the field of pyrotechnics were the motivation for a series of flame emission spectroscopy experiments with strontium-containing compounds. Specifically, strontium monoxide (SrO) was studied as a candidate radiator for the diagnosis of methane-air flames. Strontium monoxide emissions have been observed in flames with temperatures in the range 1200 K to 1600 K for two compounds: strontium hydroxide and strontium chloride. Comparisons are made of the measured SrO spectra to simulated spectra in the near-infrared region of 700 nm to 900 nm.

  10. Carbon monoxide sensors. January 1970-April 1989 (Citations from the COMPENDEX data base). Report for January 1970-April 1989

    SciTech Connect

    Not Available

    1989-04-01

    This bibliography contains citations concerning the measurement and sensing of carbon monoxide. Carbon monoxide sensors used to prevent asphyxiation, combustion, and explosion are discussed. Carbon monoxide sensors used to measure combustion efficiency and gas levels in the atmosphere are included. Designs for gas sensors that measure several gases or carbon monoxide alone are presented. Extraterrestrial applications of carbon monoxide sensors are excluded. (Contains 140 citations fully indexed and including a title list.)

  11. Carbon Monoxide Poisoning: Death on Mount McKinley,

    DTIC Science & Technology

    1987-05-08

    asphyxiation due to acute carbon monoxide poisoning. Their blood carboxyhemoglobin concentrations were measured at 56.9% and 65.6%, respectively...and chronic exposure to CO. Thus, in the presence of carboxyhemoglobin (COHb)q the tissue partial pressure of oxygen may be lower than in the case of a...Halebian, et al found no significant difference in measured 02 consumption or extraction between dogs subjected to CO poisoning vs nitrogen anoxia.(9

  12. Guideline for modeling carbon monoxide from roadway intersections

    SciTech Connect

    DiCristofaro, D.C.

    1992-11-01

    The guideline is designed to evaluate air quality impacts at one or more roadway intersections where vehicular traffic will cause or contribute to increased emissions of carbon monoxide (CO). The explicit purpose of the guideline is to provide a consistent, scientifically acceptable method for estimating the air quality impacts of vehicular traffic at intersections to determine if such impacts may exceed the National Ambient Air Quality Standards (NAAQS) for CO.

  13. [Sudden unilateral sensorineural hearing loss after carbon monoxide intoxication].

    PubMed

    Michalska-Piechowiak, Teresa; Miarzyńska, Maria; Perlik-Gattner, Irena

    2004-01-01

    A case of unilateral sensorineural hearing loss of the left ear after carbon monoxide intoxication was presented. The diagnosis was based upon an interview, medical examinations and audiometric investigations. Results of diagnostic evaluations, clinical presentation and treatment were discussed. Hearing improvement was obtained after 6 days of treatment and normal hearing returned after 14 days. Patients who suffer from CO intoxication are at risk of hearing impairment, therefore, there is a need for audiometric follow up in these patients.

  14. 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.

  15. Carbon monoxide fractions in cigarette and hookah (hubble bubble) smoke.

    PubMed

    Sajid, K M; Akhter, M; Malik, G Q

    1993-09-01

    We studied the carbon monoxide (CO) fractions in hookah and cigarette smoke, using a carbon monoxide micro smokerlyzer (model EC50, BEDFONT, U.K.). Mean carbon monoxide fractions (% by volume) of hookah smoke, using domestic charcoal were 0.38 +/- 0.07 (large hookah; unfiltered); 1.40 +/- 0.43 (small hookah; unfiltered); 0.34 +/- 0.06 (large hookah; filtered); 1.36 +/- 0.35 (small hookah; filtered) and 0.41 +/- 0.08 (cigarette smoke). The highest fractions were obtained with small size hookah and increase in size of hookah (i.e., volume of air in water base, fire bowl volume, pipe length, etc.) reduced the CO fraction significantly (P < 0.001). The fractions of cigarette lie between large and small hookah. The fractions vary slightly with different varieties of tobacco, e.g., CO fractions with Dera wala tobacco are significantly low (P < 0.05). Use of commercial charcoal gives significant rise in CO fractions (P < 0.001). Comparison of filtered and unfiltered smoke shows no significant difference in values. We conclude that the CO hazard is as high with hookah smoking as with cigarette smoking.

  16. Molecular dynamics simulation of photodissociation of carbon monoxide from hemoglobin

    SciTech Connect

    Henry, E.R.; Levitt, M.; Eaton, W.A.

    1985-04-01

    A molecular dynamics simulation of the photodissociation of carbon monoxide from the alpha subunit of hemoglobin is described. To initiate photodissociation, trajectories of the liganded molecule were interrupted, the iron-carbon monoxide bond was broken, and the parameters of the iron-nitrogen bonds were simultaneously altered to produce a deoxyheme conformation. Heme potential functions were used that reproduce the energies and forces for the iron out-of-plane motion obtained from quantum mechanical calculations. The effect of the protein on the rate and extent of the displacement of the iron from the porphyrin plane was assessed by comparing the results with those obtained for an isolated complex of heme with imidazole and carbon monoxide. The half-time for the displacement of the iron from the porphyrin plane was found to be 50-150 fs for both the protein and the isolated complex. These results support the interpretation of optical absorption studies using 250-fs laser pulses that the iron is displaced from the porphyrin plane within 350 fs in both hemoglobin and a free heme complex in solution.

  17. Carbon Monoxide and Turbulence-Chemistry Interactions: Blowoff and Extinction of Turbulent Jet Diffusion Flames

    DTIC Science & Technology

    1988-08-31

    tions has been developed. In the model, combustion chemistry is represented by two-body shuffle reac- tions and three-body recombination reactions ...The scalar dissipation field is examined for critical values, below which the two-body reactions are assumed to be in p.e. and above which they are as...sumed to be frozen and the gas therefore unburned. The kinetics of the recombination reactions are activated for the former fraction of the gas. This

  18. Formation and Fractionation of CO (Carbon Monoxide) in Diffuse Clouds Observed at Optical and Radio Wavelengths

    NASA Astrophysics Data System (ADS)

    Liszt, H. S.

    2017-02-01

    We modeled {{{H}}}2 and CO formation incorporating the fractionation and selective photodissociation affecting CO when {A}{{V}} ≲ 2 mag. UV absorption measurements typically have N({}12{CO})/N({}13{CO}) ≈ 65 that are reproduced with the standard UV radiation and little density dependence at n(H) ≈ 32–1024 {{cm}}-3: densities n(H) ≲ 256 {{cm}}-3 avoid overproducing CO. Sightlines observed in millimeter wave absorption and a few in UV show enhanced {}13{CO} by factors of two to four and are explained by higher n(H) ≳ 256 {{cm}}-3 and/or weaker radiation. The most difficult observations to understand are UV absorptions having N({}12{CO})/N({}13{CO}) > 100 and N(CO) ≳ 1015 {{cm}}-2. Plots of {W}{CO} versus N(CO) show that {W}{CO} remains linearly proportional to N(CO) even at high opacity owing to sub-thermal excitation. {}12{CO} and {}13{CO} have nearly the same curve of growth so their ratios of column density/integrated intensity are comparable even when different from the isotopic abundance ratio. For n(H) ≳ 128 {{cm}}-3, plots of {W}{CO} versus N(CO) are insensitive to n(H), and {W}{CO}/N(CO) ≈ 1 {{K}} {km} {{{s}}}-1/(1015 CO {{cm}}-2); this compensates for small CO/{{{H}}}2 to make {W}{CO} more readily detectable. Rapid increases of N(CO) with n(H), N(H), and N({{{H}}}2) often render the CO bright, i.e., a small CO-{{{H}}}2 conversion factor. For n(H) ≲ 64 {{cm}}-3, CO enters the regime of truly weak excitation, where {W}{CO} ∝ n(H)N(CO). {W}{CO} is a strong function of the average {{{H}}}2 fraction and models with {W}{CO} = 1 {{K}} {km} {{{s}}}-1 fall in the narrow range of < {f}{{{H}}2}> 0.65–0.8 or < {f}{{{H}}2}> 0.4–0.5 at {W}{CO} 0.1 {{K}} {km} {{{s}}}-1. The insensitivity of easily detected CO emission to gas with small < {f}{{{H}}2}> implies that even deep CO surveys using broad beams may not discover substantially more emission.

  19. 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.

  20. Gas adsorption capacity of wood pellets

    DOE PAGES

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; ...

    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

  1. Gas adsorption capacity of wood pellets

    SciTech Connect

    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 challenging 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.

  2. 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.

  3. 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.

  4. 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…

  5. 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)

  6. 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.

  7. Sildenafil Preserves Exercise Capacity in Patients With Idiopathic Pulmonary Fibrosis and Right-sided Ventricular Dysfunction

    PubMed Central

    Bach, David S.; Hagan, Peter G.; Yow, Eric; Flaherty, Kevin R.; Toews, Galen B.; Anstrom, Kevin J.; Martinez, Fernando J.

    2013-01-01

    Background: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with pulmonary vasculopathy. Objective: The purpose of this study was to determine whether sildenafil improves 6-min walk distance (6MWD) in subjects with IPF and right ventricular dysfunction. Methods: The IPFnet, a network of IPF research centers in the United States, conducted a randomized trial examining the effect of sildenafil on 6MWD in patients with advanced IPF, defined by carbon monoxide diffusing capacity < 35% predicted. A substudy examined 119 of 180 randomized subjects where echocardiograms were available for independent review by two cardiologists. Right ventricular (RV) hypertrophy (RVH), right ventricular systolic dysfunction (RVSD), and right ventricular systolic pressure (RVSP) were assessed. Multivariable linear regression models estimated the relationship between RV abnormality, sildenafil treatment, and changes in 6MWD, St. George’s Respiratory Questionnaire (SGRQ), the EuroQol instrument, and SF-36 Health Survey (SF-36) from enrollment to 12 weeks. Results: The prevalence of RVH and RVSD were 12.8% and 18.6%, respectively. RVSP was measurable in 71 of 119 (60%) subjects; mean RVSP was 42.5 mm Hg. In the subgroup of subjects with RVSD, subjects treated with sildenafil experienced less decrement in 6MWD (99.3 m; P = .01) and greater improvement in SGRQ (13.4 points; P = .005) and EuroQol visual analog scores (17.9 points; P = .04) than subjects receiving placebo. In the subgroup with RVH, sildenafil was not associated with change in 6MWD (P = .13), but was associated with greater relative improvement in SGRQ (14.8 points; P = .02) vs subjects receiving placebo. Sildenafil treatment in those with RVSD and RVH was not associated with change in SF-36. Conclusions: Sildenafil treatment in IPF with RVSD results in better preservation of exercise capacity as compared with placebo. Sildenafil also improves quality of life in subjects with RVH and RVSD. PMID:23732584

  8. Effects of Finite Reaction Rates on the Kinetic Phase Transitions in the Catalytic Oxidation of Carbon Monoxide

    NASA Astrophysics Data System (ADS)

    López-Carreño, L. D.

    Oxidation of carbon monoxide is one of the most extensively studied heterogeneous catalysis reactions, being important among other applications in automobile-emission control. Catalytic oxidation of carbon monoxide on platinum (111) surface was simulated by the Monte Carlo technique following an extended version of the model proposed by Ziff, Gulari and Barshad (ZGB). In the simulation, a simple square two-dimensional lattice of active sites replaces the surface of the catalyst. Finite reaction rates for (i) diffusion of the reactive species on the surface, (ii) reaction of a CO molecule with an oxygen atom in a nearest neighbor site, and (iii) desorption of unreacted CO molecules, have been taken into account. The produced CO2 desorbs instantly. The average coverage of O, CO and the CO2 production rate for a steady state configuration, as a function of the normalized CO partial pressure (PCO), shows two kinetic phase transitions. In the ZGB model these transitions occur at PCO ~ 0.39 and PCO ~ 0.53. For 0.39 < PCO > 0.53 a reactive (CO2 production) steady state is found. Outside of the interval, the only steady state is a poisoned catalyst of pure CO or pure O. Our results show that finite reaction rates shift the values in which these phase transitions occur.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Electron magnetic resonance investigation of chromium diffusion in yttria powders

    NASA Astrophysics Data System (ADS)

    de Biasi, R. S.; Grillo, M. L. N.

    2010-03-01

    The electron magnetic resonance (EMR) technique was used to investigate the diffusion of chromium in yttria (Y 2O 3) powders. The EMR absorption intensity was measured for several annealing times and three different temperatures of isothermal annealing: 1273, 1323 and 1373 K. The activation temperature for diffusion, calculated from the experimental data using a theoretical model based on the Fick equation, was found to be E A=342±5 kJ mol -1. This value is larger than the activation energy for the diffusion of chromium in rutile (TiO 2), periclase (MgO) and cobalt monoxide (CoO) and smaller than the activation energy for the diffusion of chromium in chrysoberyl (BeAl 2O 4).

  14. 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

  15. Transient PrOx carbon monoxide measurement, control, and optimization

    SciTech Connect

    Inbody, M. A.; Borup, R. L.; Tafoya, J.

    2002-01-01

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

  16. Compact carbon monoxide sensor utilizing a confocal optical cavity.

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

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

  17. Comparison between carbon monoxide measurements from spaceborne and airborne platforms

    NASA Technical Reports Server (NTRS)

    Connors, V. S.; Cahoon, D. R.; Reichle, H. G., Jr.; Scheel, H. E.

    1991-01-01

    The measurements of air pollution from satellites (MAPS) experiment measured the distribution of middle tropospheric carbon monoxide (CO) from the Space Shuttle during October 1984. A critical area of the experiment is the assessment of experimental error of the MAPS data. This error is determined by the comparison between the space-based CO data and concurrent, direct CO measurements taken aboard aircraft. Because of the variability in the CO measurements near land sources, a strategy for comparing the tropospheric CO measurements over the remote oceans is presented.

  18. Pathways and Bioenergetics of Anaerobic Carbon Monoxide Fermentation.

    PubMed

    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.

  19. Thermal Degradation of Lead Monoxide Filled Polymer Composite Radiation Shields

    NASA Astrophysics Data System (ADS)

    Harish, V.; Nagaiah, N.

    2011-07-01

    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 & 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.

  20. [Acute carbon monoxide poisoning after water pipe tobacco smoking].

    PubMed

    Paulsen, Jakob Felbo; Villads, Kasper von Rosen; Sonne, Morten Egede

    2016-12-05

    Carbon monoxide poisoning is potentially lethal, and early recognition and treatment is essential. An 18-year-old man was admitted due to syncope and a carboxyhaemoglobin level of 17% after water pipe tobacco smoking. He received normo- and hyperbaric oxygen as treatment and was discharged after two days without neurological sequelae. This case is the first in Denmark, but recently seven similar cases have been reported. The number of young people smoking water pipe tobacco is increasing, and we fear that more cases like this will occur in the future.

  1. 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.

  2. Cardiovascular effects of chronic carbon monoxide and high-altitude exposure.

    PubMed

    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. I conclude that six weeks of exposure to 35 ppm carbon monoxide does not produce measurable effects in the healthy laboratory rat, nor does it

  3. 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.

  4. Far-ultraviolet fluorescence of carbon monoxide in the red giant Arcturus. II - Analysis of high-dispersion IUE spectra

    NASA Technical Reports Server (NTRS)

    Ayres, T. R.

    1986-01-01

    Faint, diffuse emissions near 1380 A in deeply exposed IUE spectrograms of the red giant Arcturus very likely are associated with bands of the A-X fourth-positive system of carbon monoxide, fluoresced by multiplet UV2 of neutral oxygen near 1305 A. Numerical simulations indicate that the strength of the CO bands is exceedingly sensitive, in the best available one-dimensional model of the chromosphere of Arcturus, to a delicate balance between the rapid inward attenuation of the oxygen radiation field and the rapid outward decline of the molecular absorptivity. The fortuitous character of the overlap region in the single-component model argues that one should also consider the possibility that the pumping occurs in a highly inhomogeneous chromosphere, of the type proposed in previous studies of Arcturus based on observations of the infrared absorption bands of CO.

  5. Relation between brain temperature and white matter damage in subacute carbon monoxide poisoning

    PubMed Central

    Fujiwara, Shunrou; Yoshioka, Yoshichika; Matsuda, Tsuyoshi; Nishimoto, Hideaki; Ogawa, Akira; Ogasawara, Kuniaki; Beppu, Takaaki

    2016-01-01

    In the previous studies, carbon monoxide (CO) poisoning showed an imbalance between cerebral perfusion and metabolism in the acute phase and the brain temperature (BT) in these patients remained abnormally high from the acute to the subacute phase. As observed in chronic ischemic patients, BT can continuously remain high depending on impairments of cerebral blood flow and metabolism; this is because heat removal and production system in the brain may mainly be maintained by the balance of these two factors; thus, cerebral white matter damage (WMD) affecting normal metabolism may affect the BT in patients with CO poisoning. Here, we investigated whether the BT correlates with the degree of WMD in patients with subacute CO-poisoning. In 16 patients with subacute CO-poisoning, the BT and degree of WMD were quantitatively measured by using magnetic resonance spectroscopy and the fractional anisotropy (FA) value from diffusion tensor imaging dataset. Consequently, the BT significantly correlated with the degree of WMD. In particular, BT observed in patients with delayed neuropsychiatric sequelae, a crucial symptom with sudden-onset in the chronic phase after CO exposure, might indicate cerebral hypo-metabolism and abnormal hemodynamics like “matched perfusion,” in which the reduced perfusion matches the reduced metabolism. PMID:27819312

  6. Femtosecond, two-photon, planar laser-induced fluorescence of carbon monoxide in flames.

    PubMed

    Richardson, Daniel R; Roy, Sukesh; Gord, James R

    2017-02-15

    Two-photon, planar laser-induced fluorescence (TP-PLIF) of carbon monoxide was performed in steady and driven flames using femtosecond (fs) laser pulses at 1 kHz. Excitation radiation at 230.1 nm (full-width at half-maximum bandwidth of 270  cm-1) was used to pump many rovibrational two-photon transitions in the B1+←X1+ system. Visible fluorescence in the range 362-516 nm was captured using an image intensifier and high-speed camera. The signal dependence on excitation energy and wavelength is presented. Photolytic interferences from the ultraviolet laser were explored in a sooting diffusion flame. Using an excitation laser intensity of 1010  W/cm2, negligible photolytic interferences were observed, and PLIF imaging of dynamic flame events was performed at 1 kHz.

  7. 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.

  8. Material processing with hydrogen and carbon monoxide on Mars

    NASA Technical Reports Server (NTRS)

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

    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 hydrocarbons. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquid. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

  9. 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.

  10. 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.

  11. Portable device for monitoring consistency of carbon monoxide

    NASA Astrophysics Data System (ADS)

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

    2002-06-01

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

  12. Combustion characteristics of hydrogen. Carbon monoxide based gaseous fuels

    NASA Astrophysics Data System (ADS)

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

    1981-10-01

    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.

  13. 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

  14. Carbon Monoxide Emissions in Middle Aged Debris Disks

    NASA Astrophysics Data System (ADS)

    Henderson, Morgan; Gorti, Uma; Hales, Antonio; Carpenter, John M.; Hughes, A. Meredith

    2017-01-01

    Circumstellar disks greater than 10 Myr old, referred to as debris disks, are expected to be gas poor. The original gas and dust in these disks is thought to be accreted onto the host stars, used up in the formation of planets and other bodies, or blown out of the disks via stellar radiation. However, recent ALMA observations at millimeter wavelengths have led to the detection of carbon monoxide (J=2-1) emission in a few debris disks, prompting further investigation.Using ALMA data, two separate models of gas genesis were tested against observations of the CO emissions in the disks around HIP 73145, HIP 76310, and HIP 84881 in the Upper Sco association. One of these models was built on the hypothesis that the gas in these debris disks is left over from stellar formation and has persisted over uncommonly long periods of time. The other model is built on the hypothesis that this gas is of secondary nature, produced by collisions between planetary bodies in the debris disks. Model emissions were calculated using the Line Modeling Engine (LIME) radiative transfer code and were compared with observational data to infer gas masses under both production scenarios. The implications of the masses of carbon monoxide in the disks suggested by each of the two models are discussed.

  15. The electric dipole moment of cobalt monoxide, CoO

    SciTech Connect

    Zhuang, Xiujuan; Steimle, Timothy C.

    2014-03-28

    A number of low-rotational lines of the E{sup 4}Δ{sub 7/2} ← X{sup 4}Δ{sub 7/2} (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h{sub 7/2}, and the electron quadrupole parameter, eQq{sub 0}, for the E{sup 4}Δ{sub 7/2}(υ = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, μ{sup -vector}{sub el}, for the X{sup 4}Δ{sub 7/2} (υ = 0) and E{sup 4}Δ{sub 7/2} (υ = 1) states were determined to be 4.18 ± 0.05 D and 3.28 ± 0.05 D, respectively, from the analysis of the observed Stark spectra of F′ = 7 ← F″ = 6 branch feature in the Q(7/2) line and the F′ = 8 ← F″ = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed.

  16. 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.

  17. The electric dipole moment of cobalt monoxide, CoO.

    PubMed

    Zhuang, Xiujuan; Steimle, Timothy C

    2014-03-28

    A number of low-rotational lines of the E(4)Δ7/2 ← X(4)Δ7/2 (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h7/2, and the electron quadrupole parameter, eQq0, for the E(4)Δ7/2(υ = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, μ(→)(el), for the X(4)Δ7/2 (υ = 0) and E(4)Δ7/2 (υ = 1) states were determined to be 4.18 ± 0.05 D and 3.28 ± 0.05 D, respectively, from the analysis of the observed Stark spectra of F' = 7 ← F″ = 6 branch feature in the Q(7/2) line and the F' = 8 ← F″ = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed.

  18. 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)

  19. 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.

  20. 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...

  1. 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...

  2. Catalytic carbon for oxidation of carbon monoxide in the presence of sulfur dioxide

    SciTech Connect

    Sinha, R.K.

    1980-01-22

    A carbon supported catalyst used for carbon monoxide oxidation is chemically modified by treating the activated carbon support with an oxidizing agent and/or a hydrophobic compound prior to impregnation with the catalyst mixture. The thus treated catalytic carbon is capable of oxidizing carbon monoxide in an air stream containing sulfur dioxide over an extended period of time.

  3. 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...

  4. 78 FR 48638 - Approval and Promulgation of State Implementation Plans: Alaska; Fairbanks Carbon Monoxide...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of State Implementation Plans: Alaska; Fairbanks Carbon.... SUMMARY: The EPA is proposing to approve a carbon monoxide Limited Maintenance Plan for the Fairbanks Area... demonstrates that the Fairbanks Area will maintain the carbon monoxide National Ambient Air Quality...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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.

  10. The study of dehumidifying of carbon monoxide and ammonia adsorption by Iranian natural clinoptilolite zeolite

    NASA Astrophysics Data System (ADS)

    Tehrani, R. M. A.; Salari, A. A.

    2005-10-01

    The natural zeolite (clinoptilolite type) was obtained from the Neibagh region of Mianeh, the city in the west of Iran. The raw zeolite was tested for quality and quantity measurements including surface area and volumetric characteristics as well as thermogravimetry analysis. The acid activation process was used to increase the adsorption rate of zeolite and in order to obtain the optimum conditions: the effect of acid concentration, reaction time and the temperature were studied. A surface area measurement test was performed in each stage to get the best results. Thus, efficient condition was selected according to the produced highest surface area. The reaction was first obtained with hydrochloric acid, and then a comparison was made using the sulfuric acid. The hydrochloric reaction proved to be better. The result of activation was 2.5 times the increase in the surface area in relation to the raw sample. The result of elemental analysis conducted once again on the activated sample showed an increase in the ratio of Si/Al (approximately 0.6). Then, using CO, NH 3 and steam, the gas adsorption capacity of both the raw and activated samples was measured and compared. Since CO was not adsorbed at ambient temperature, but steam was adsorbed relatively well, the natural clinoptilolite zeolite of Iran was suggested as a suitable material for adsorbing humidity form carbon monoxide as well as synthesis gas (H 2 and CO mixture).

  11. 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.

  12. 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.

  13. Macrophages sense and kill bacteria through carbon monoxide-dependent inflammasome activation.

    PubMed

    Wegiel, Barbara; Larsen, Rasmus; Gallo, David; Chin, Beek Yoke; Harris, Clair; Mannam, Praveen; Kaczmarek, Elzbieta; Lee, Patty J; Zuckerbraun, Brian S; Flavell, Richard; Soares, Miguel P; Otterbein, Leo E

    2014-11-01

    Microbial clearance by eukaryotes relies on complex and coordinated processes that remain poorly understood. The gasotransmitter carbon monoxide (CO) is generated by the stress-responsive enzyme heme oxygenase-1 (HO-1, encoded by Hmox1), which is highly induced in macrophages in response to bacterial infection. HO-1 deficiency results in inadequate pathogen clearance, exaggerated tissue damage, and increased mortality. Here, we determined that macrophage-generated CO promotes ATP production and release by bacteria, which then activates the Nacht, LRR, and PYD domains-containing protein 3 (NALP3) inflammasome, intensifying bacterial killing. Bacterial killing defects in HO-1-deficient murine macrophages were restored by administration of CO. Moreover, increased CO levels enhanced the bacterial clearance capacity of human macrophages and WT murine macrophages. CO-dependent bacterial clearance required the NALP3 inflammasome, as CO did not increase bacterial killing in macrophages isolated from NALP3-deficient or caspase-1-deficient mice. IL-1β cleavage and secretion were impaired in HO-1-deficient macrophages, and CO-dependent processing of IL-1β required the presence of bacteria-derived ATP. We found that bacteria remained viable to generate and release ATP in response to CO. The ATP then bound to macrophage nucleotide P2 receptors, resulting in activation of the NALP3/IL-1β inflammasome to amplify bacterial phagocytosis by macrophages. Taken together, our results indicate that macrophage-derived CO permits efficient and coordinated regulation of the host innate response to invading microbes.

  14. Soil uptake of carbon monoxide emitted in the exhaust of a gasoline-powered engine.

    PubMed

    Tilley, David R; Mentzer, Jeff

    2006-02-01

    Carbon monoxide (CO) poses dangers to both human and environmental health, sickening thousands of people annually in the United States and decreasing the capacity of the atmosphere to oxidize greenhouse gases. Globally, soil ecosystems with their populations of bacteria, fungi, and algae are estimated to remove 9-36% of total CO emissions, which makes them the second largest CO sink after hydroxyl oxidation. Our aim was determine whether soil ecosystems could remove CO from an atmosphere mixed with gasoline-powered engine exhaust. Sealed microcosms containing no soil (NoSoil), nonvegetated soil (Soil), or vegetated soil (Soil+Veg), were exposed to 800, 100, and 50 ppm of CO for 1 hr. The uptake rate of CO was found to be higher at the 800 ppm level suggesting first-order rate kinetics. Soil+Veg exhibited a significantly higher CO uptake rate than either Soil or NoSoil (P<0.05), and Soil exhibited significantly higher uptake than NoSoil (P<0.05). As a free ecosystem service, the uptake of CO by soil ecosystems needs to be properly valued and ecologically engineered into the urban traffic network in a manner analogous to how wetlands, vegetated swales, and other ecologically based storm water treatment systems have improved urban runoff.

  15. 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.

  16. 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.

  17. A comparative study of analytical methods to determine postmortem changes in carbon monoxide concentration.

    PubMed

    Winek, C L; Prex, D M

    1981-01-01

    Twenty-one autopsy blood samples were analyzed using spectrophotometric and gas chromatographic procedures after storage for 30 and 150 days. When carboxyhemoglobin was measured spectrophotometrically at the absorbance ratio of 540 nm/555 nm, the observed average percent losses were 8 +/- 9% and 35 +/- 27% after 30 and 150 days of storage, respectively. When measured at the absorbance ratio of 540 nm/579 nm, the average percent losses of carboxyhemoglobin were 7 +/- 8% and 34 +/- 25% after 30 and 150 days, respectively. Wavelength shifts and distorted spectral scans were observed at 150 days. When carbon monoxide was determined by gas chromatographic methods based on combining capacity, the average percent loss was 15 +/- 24% and 37 +/- 36% after 30 days and 150 days, respectively. The average percent loss of calculated CO based on hemoglobin concentration after 30 days was 31 +/- 14% and at 150 days, 40 +/- 24%. The average percent loss of calculated CO based on iron content was 23 +/- 13% and 37 +/- 23% after 30 and 150 days, respectively.

  18. Carbon monoxide-bound hemoglobin-vesicles for the treatment of bleomycin-induced pulmonary fibrosis.

    PubMed

    Nagao, Saori; Taguchi, Kazuaki; Sakai, Hiromi; Tanaka, Ryota; Horinouchi, Hirohisa; Watanabe, Hiroshi; Kobayashi, Koichi; Otagiri, Masaki; Maruyama, Toru

    2014-08-01

    Carbon monoxide (CO) has potent anti-inflammatory and anti-oxidant effects. We report herein on the preparation of a nanotechnology-based CO donor, CO-bound hemoglobin-vesicles (CO-HbV). We hypothesized that CO-HbV could have a therapeutic effect on idiopathic pulmonary fibrosis (IPF), an incurable lung fibrosis, that is thought to involve inflammation and the production of reactive oxygen species (ROS). Pulmonary fibril formation and respiratory function were quantitatively evaluated by measuring hydroxyproline levels and forced vital capacity, respectively, using a bleomycin-induced pulmonary fibrosis mice model. CO-HbV suppressed the progression of pulmonary fibril formation and improved respiratory function compared to saline and HbV. The suppressive effect of CO-HbV on pulmonary fibrosis can be attributed to a decrease in ROS generation by inflammatory cells, NADPH oxidase 4 and the production of inflammatory cells, cytokines and transforming growth factor-β in the lung. This is the first demonstration of the inhibitory effect of CO-HbV on the progression of pulmonary fibrosis via the anti-oxidative and anti-inflammatory effects of CO in the bleomycin-induced pulmonary fibrosis mice model. CO-HbV has the potential for use in the treatment of, not only IPF, but also a variety of other ROS and inflammation-related disorders.

  19. 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

  20. Syngas fermentation to biofuel: evaluation of carbon monoxide mass transfer coefficient (kLa) in different reactor configurations.

    PubMed

    Munasinghe, Pradeep Chaminda; Khanal, Samir Kumar

    2010-01-01

    Lignocellulosic biomass such as agri-residues, agri-processing by-products, and energy crops do not compete with food and feed, and is considered to be the ideal renewable feedstocks for biofuel production. Gasification of biomass produces synthesis gas (syngas), a mixture primarily consisting of CO and H(2). The produced syngas can be converted to ethanol by anaerobic microbial catalysts especially acetogenic bacteria such as various clostridia species.One of the major drawbacks associated with syngas fermentation is the mass transfer limitation of these sparingly soluble gases in the aqueous phase. One way of addressing this issue is the improvement in reactor design to achieve a higher volumetric mass transfer coefficient (k(L)a). In this study, different reactor configurations such as a column diffuser, a 20-μm bulb diffuser, gas sparger, gas sparger with mechanical mixing, air-lift reactor combined with a 20-μm bulb diffuser, air-lift reactor combined with a single gas entry point, and a submerged composite hollow fiber membrane (CHFM) module were employed to examine the k(L) a values. The k(L) a values reported in this study ranged from 0.4 to 91.08 h(-1). The highest k(L) a of 91.08 h(-1) was obtained in the air-lift reactor combined with a 20-μm bulb diffuser, whereas the reactor with the CHFM showed the lowest k(L) a of 0.4 h(-1). By considering both the k(L) a value and the statistical significance of each configuration, the air-lift reactor combined with a 20-μm bulb diffuser was found to be the ideal reactor configuration for carbon monoxide mass transfer in an aqueous phase.

  1. 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.

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. Physiologically based pharmacokinetic modeling with dichloromethane, its metabolite, carbon monoxide, and blood carboxyhemoglobin in rats and humans.

    PubMed

    Andersen, M E; Clewell, H J; Gargas, M L; MacNaughton, M G; Reitz, R H; Nolan, R J; McKenna, M J

    1991-03-15

    Dichloromethane (methylene chloride, DCM) and other dihalomethanes are metabolized to carbon monoxide (CO) which reversibly binds hemoglobin and is eliminated by exhalation. We have developed a physiologically based pharmacokinetic (PB-PK) model which describes the kinetics of CO, carboxyhemoglobin (HbCO), and parent dihalomethane, and have applied this model to examine the inhalation kinetics of CO and of DCM in rats and humans. The portion of the model describing CO and HbCO kinetics was adapted from the Coburn-Forster-Kane equation, after modification to include production of CO by DCM oxidation. DCM kinetics and metabolism were described by a generic PB-PK model for volatile chemicals (RAMSEY AND ANDERSEN, Toxicol. Appl. Pharmacol. 73, 159-175, 1984). Physiological and biochemical constants for CO were first estimated by exposing rats to 200 ppm CO for 2 hr and examining the time course of HbCO after cessation of CO exposure. These CO inhalation studies provided estimates of CO diffusing capacity under free breathing and for the Haldane coefficient, the relative equilibrium distribution ratio for hemoglobin between CO and O2. The CO model was then coupled to a PB-PK model for DCM to predict HbCO time course behavior during and after DCM exposures in rats. By coupling the models it was possible to estimate the yield of CO from oxidation of DCM. In rats only about 0.7 mol of CO are produced from 1 mol of DCM during oxidation. The combined model adequately represented HbCO and DCM behavior following 4-hr exposures to 200 or 1000 ppm DCM, and HbCO behavior following 1/2-hr exposure to 5160 ppm DCM or 5000 ppm bromochloromethane. The rat PB-PK model was scaled to predict DCM, HbCO, and CO kinetics in humans exposed either to DCM or to CO. Three human data sets from the literature were examined: (1) inhalation of CO at 50, 100, 250, and 500 ppm; (2) seven 1/2-hr inhalation exposures to 50, 100, 250, and 500 ppm DCM; and (3) 2-hr inhalation exposures to 986 ppm DCM

  13. Measurement of endogenous carbon monoxide formation in biological systems.

    PubMed

    Marks, Gerald S; Vreman, Hendrik J; McLaughlin, Brian E; Brien, James F; Nakatsu, Kanji

    2002-04-01

    Endogenous carbon monoxide (CO) formation has been measured in different biological systems using a variety of analytical procedures. The methods include gas chromatography-reduction gas detection, gas chromatography-mass spectroscopic detection, laser sensor-infrared absorption, UV-visible spectrophotometric measurement of CO-hemoglobin or CO-myoglobin complex, and formation of (14)CO from (14)C-heme formed following [2-(14)C]glycine administration. CO formation ranged from a low of 0.029 nmol/mg of protein/h in chorionic villi of term human placenta to a high of 0.28 nmol/mg of protein/h in rat olfactory receptor neurons in culture and rat liver perfusate.

  14. Methanation of gas streams containing carbon monoxide and hydrogen

    DOEpatents

    Frost, Albert C.

    1983-01-01

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

  15. The oxidation of carbon monoxide using a tin oxide catalyst

    NASA Technical Reports Server (NTRS)

    Sampson, Christopher F.; Gudde, Nicholas J.

    1987-01-01

    This paper outlines some of the steps involved in the development by the United Kingdom Atomic Energy Authority (UKAEA) of a catalytic device for the recombination of carbon monoxide and oxygen in a CO2 laser system. It contrasts the differences between CO oxidation for air purification and for laser environmental control, but indicates that there are similarities between the physical specifications. The principal features of catalytic devices are outlined and some experimental work described. This includes measurements concerning the structure and mechanical properties of the artifact, the preparation of the catalyst coating and its interaction with the gaseous environment. The paper concludes with some speculation about the method by which the reaction actually occurs.

  16. Carbon monoxide expedites metabolic exhaustion to inhibit tumor growth.

    PubMed

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

    2013-12-01

    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.

  17. Carbon monoxide: a role in carotid body chemoreception.

    PubMed

    Prabhakar, N R; Dinerman, J L; Agani, F H; Snyder, S H

    1995-03-14

    Carbon monoxide (CO), produced endogenously by heme oxygenase, has been implicated as a neuronal messenger. Carotid bodies are sensory organs that regulate ventilation by responding to alterations of blood oxygen, CO2, and pH. Changes in blood gases are sensed by glomus cells in the carotid body that synapse on afferent terminals of the carotid sinus nerve that projects to respiratory-related neurons in the brainstem. Using immunocytochemistry, we demonstrate that heme oxygenase 2 is localized to glomus cells in the cat and rat carotid bodies. Physiological studies show that zinc protoporphyrin IX, a potent heme oxygenase inhibitor, markedly increases carotid body sensory activity, while copper protoporphyrin IX, which does not inhibit the enzyme, is inactive. Exogenous CO reverses the stimulatory effects of zinc protoporphyrin IX. These results suggest that glomus cells are capable of synthesizing CO and endogenous CO appears to be a physiologic regulator of carotid body sensory activity.

  18. Venus - Detection of variations in stratospheric carbon monoxide

    NASA Technical Reports Server (NTRS)

    Gulkis, S.; Kakar, R. K.; Klein, M. J.; Olsen, E. T.; Wilson, W. J.

    1978-01-01

    The reported observations of the J = 0-1 rotational transition (115271.2 MHz) of carbon monoxide in the Venusian atmosphere indicate that the distribution of stratospheric CO is variable. Observations were obtained with a 11-m antenna on several days in February 1977, when Venus was near maximum eastern elongation (k approximately 0.4), and in April 1977 during inferior conjunction (k approximately 0.01). Differences in the line intensities and shapes for the two data sets are described. The results are interpreted to suggest that on the nightside of Venus there is relatively more CO at higher altitudes and relatively less CO at lower altitudes than on the dayside of the planet.

  19. Carbon monoxide in an extremely metal-poor galaxy.

    PubMed

    Shi, Yong; Wang, Junzhi; Zhang, Zhi-Yu; Gao, Yu; Hao, Cai-Na; Xia, Xiao-Yang; Gu, Qiusheng

    2016-12-09

    Extremely metal-poor galaxies with metallicity below 10% of the solar value in the local universe are the best analogues to investigating the interstellar medium at a quasi-primitive environment in the early universe. In spite of the ongoing formation of stars in these galaxies, the presence of molecular gas (which is known to provide the material reservoir for star formation in galaxies such as our Milky Way) remains unclear. Here we report the detection of carbon monoxide (CO), the primary tracer of molecular gas, in a galaxy with 7% solar metallicity, with additional detections in two galaxies at higher metallicities. Such detections offer direct evidence for the existence of molecular gas in these galaxies that contain few metals. Using archived infrared data, it is shown that the molecular gas mass per CO luminosity at extremely low metallicity is approximately one-thousand times the Milky Way value.

  20. 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.

  1. Hypervalence in monoxides and dioxides of superalkali clusters

    NASA Astrophysics Data System (ADS)

    Cochran, Elizabeth; Meloni, Giovanni

    2014-05-01

    F2Li3, a superalkali cluster, is characterized as having a lower adiabatic ionization energy than its elemental alkali counterpart and, coupled with the presence of complex molecular orbitals, suggests promise for novel bonding possibilities. CBS-QB3 composite method was used to study three distinct cluster isomers, as well as their cationic (+1) and anionic (-1) species, to identify energetic trends and observe geometric changes. Oxides were then generated from these clusters, of which three distinct monoxides and nine dioxides were obtained upon structure optimization. Identical calculations were performed for the oxide species and their charged counterparts. Some of the most stable oxides produced appear to possess hypervalent lithium and oxygen atoms, forming unique structures with exceptional stability.

  2. 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

  3. Carbon monoxide in an extremely metal-poor galaxy

    PubMed Central

    Shi, Yong; Wang, Junzhi; Zhang, Zhi-Yu; Gao, Yu; Hao, Cai-Na; Xia, Xiao-Yang; Gu, Qiusheng

    2016-01-01

    Extremely metal-poor galaxies with metallicity below 10% of the solar value in the local universe are the best analogues to investigating the interstellar medium at a quasi-primitive environment in the early universe. In spite of the ongoing formation of stars in these galaxies, the presence of molecular gas (which is known to provide the material reservoir for star formation in galaxies such as our Milky Way) remains unclear. Here we report the detection of carbon monoxide (CO), the primary tracer of molecular gas, in a galaxy with 7% solar metallicity, with additional detections in two galaxies at higher metallicities. Such detections offer direct evidence for the existence of molecular gas in these galaxies that contain few metals. Using archived infrared data, it is shown that the molecular gas mass per CO luminosity at extremely low metallicity is approximately one-thousand times the Milky Way value. PMID:27934880

  4. [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.

  5. Carbon monoxide measurement in the global atmospheric sampling program

    NASA Technical Reports Server (NTRS)

    Dudzinski, T. J.

    1979-01-01

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

  6. 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.

  7. Separation of Carbon Monoxide and Carbon Dioxide for Mars ISRU

    NASA Technical Reports Server (NTRS)

    Walton, Krista S.; LeVan, M. Douglas

    2004-01-01

    The atmosphere of Mars has many resources that can be processed to produce things such as oxygen, fuel, buffer gas, and water for support of human exploration missions. Successful manipulation of these resources is crucial for safe, cost-effective, and self-sufficient long-term human exploration of Mars. In our research, we are developing enabling technologies that require fundamental knowledge of adsorptive gas storage and separation processes. In particular, we are designing and constructing an innovative, low mass, low power separation device to recover carbon dioxide and carbon monoxide for Mars ISRU (in-situ resource utilization). The technology has broad implications for gas storage and separations for gas-solid systems that are ideally suited for reduced gravitational environments. This paper describes our separation process design and experimental procedures and reports results for the separation of CO2 and CO by a four-step adsorption cycle.

  8. UV-induced carbon monoxide emission from living vegetation

    NASA Astrophysics Data System (ADS)

    Bruhn, D.; Albert, K. R.; Mikkelsen, T. N.; Ambus, P.

    2013-06-01

    The global burden of carbon monoxide (CO) is rather uncertain. In this paper we address the potential for UV-induced CO emission by living terrestrial vegetation surfaces. Real-time measurements of CO concentrations were made with a cavity enhanced laser spectrometer connected in closed loop to either an ecosystem chamber or a plant-leaf scale chamber. Leaves of all examined plant species exhibited emission of CO in response to artificial UV-radiation as well as the UV-component of natural solar radiation. The UV-induced rate of CO emission exhibited a rather low dependence on temperature, indicating an abiotic process. The emission of CO in response to the UV-component of natural solar radiation was also evident at the ecosystem scale.

  9. 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.

  10. 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.

  11. 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.

  12. OMI observations of bromine monoxide emissions from salt lakes

    NASA Astrophysics Data System (ADS)

    Suleiman, R. M.; Chance, K.; Liu, X.; Gonzalez Abad, G.; Kurosu, T. P.

    2015-12-01

    In this study, we analyze bromine monoxide (BrO) data from the Ozone Monitoring Instrument (OMI) over various salt lakes. We used OMI data from 2005 to 2014 to investigate BrO signatures from salt lakes. The salt lakes regions we cover include Dead Sea; Salt Lake City, US; Salar de Uyuni, Bolivia; and Namtso, Tibet. Elevated signatures of BrO was found in July and August BrO monthly averages over the Dead Sea. Similar results were found in the BrO monthly averages for August 2006 for the Bolivian Salt Flats. We present a detailed description of the retrieval algorithm for the OMI operational bromine monoxide (BrO) product. The algorithm is based on direct fitting of radiances from 319.0-347.5 nm, within the UV-2 channel of OMI. Radiances are modeled from the solar irradiance, attenuated by contributions from the target gas and interfering gases, rotational Raman scattering, additive and multiplicative closure polynomials and a common mode spectrum. The common mode spectra (one per cross-track position, computed on-line) are the average of several hundred fitting residuals. They include any instrument effects that are unrelated to molecular scattering and absorption cross sections. The BrO retrieval uses albedo- and wavelength-dependent air mass factors (AMFs), which have been pre-computed using climatological BrO profiles. The wavelength-dependent AMF is applied pre-fit to the BrO cross-sections so that vertical column densities are retrieved directly. We validate OMI BrO with ground-based measurements from three stations (Harestua, Lauder, and Barrow) and with chemical transport model simulations. We analyze the global distribution and seasonal variation of BrO and investigate BrO emissions from volcanoes and salt lakes.

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

    NASA Astrophysics Data System (ADS)

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

    2005-04-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

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

  16. Diffusion archeology for diffusion progression history reconstruction.

    PubMed

    Sefer, Emre; Kingsford, Carl

    2016-11-01

    Diffusion through graphs can be used to model many real-world processes, such as the spread of diseases, social network memes, computer viruses, or water contaminants. Often, a real-world diffusion cannot be directly observed while it is occurring - perhaps it is not noticed until some time has passed, continuous monitoring is too costly, or privacy concerns limit data access. This leads to the need to reconstruct how the present state of the diffusion came to be from partial diffusion data. Here, we tackle the problem of reconstructing a diffusion history from one or more snapshots of the diffusion state. This ability can be invaluable to learn when certain computer nodes are infected or which people are the initial disease spreaders to control future diffusions. We formulate this problem over discrete-time SEIRS-type diffusion models in terms of maximum likelihood. We design methods that are based on submodularity and a novel prize-collecting dominating-set vertex cover (PCDSVC) relaxation that can identify likely diffusion steps with some provable performance guarantees. Our methods are the first to be able to reconstruct complete diffusion histories accurately in real and simulated situations. As a special case, they can also identify the initial spreaders better than the existing methods for that problem. Our results for both meme and contaminant diffusion show that the partial diffusion data problem can be overcome with proper modeling and methods, and that hidden temporal characteristics of diffusion can be predicted from limited data.

  17. Effect of pressure on structure and NO sub X formation in CO-air diffusion flames

    NASA Technical Reports Server (NTRS)

    Maahs, H. G.; Miller, I. M.

    1979-01-01

    A study was made of nitric oxide formation in a laminar CO-air diffusion flame over a pressure range from 1 to 50 atm. The carbon monoxide (CO) issued from a 3.06 mm diameter port coaxially into a coflowing stream of air confined within a 20.5 mm diameter chimney. Nitric oxide concentrations from the flame were measured at two carbon monoxide (fuel) flow rates: 73 standard cubic/min and 146 sccm. Comparison of the present data with data in the literature for a methane-air diffusion flame shows that for flames of comparable flame height (8 to 10 mm) and pseudoequivalence ratio (0.162), the molar emission index of a CO-air flame is significantly greater than that of a methane-air flame.

  18. Extended Molecular Dynamics Simulation of the Carbon Monoxide Migration in Sperm Whale Myoglobin

    PubMed Central

    Bossa, Cecilia; Anselmi, Massimiliano; Roccatano, Danilo; Amadei, Andrea; Vallone, Beatrice; Brunori, Maurizio; Di Nola, Alfredo

    2004-01-01

    We report the results of an extended molecular dynamics simulation on the migration of photodissociated carbon monoxide in wild-type sperm whale myoglobin. Our results allow following one possible ligand migration dynamics from the distal pocket to the Xe1 cavity via a path involving the other xenon binding cavities and momentarily two additional packing defects along the pathway. Comparison with recent time resolved structural data obtained by Laue crystallography with subnanosecond to millisecond resolution shows a more than satisfactory agreement. In fact, according to time resolved crystallography, CO, after photolysis, can occupy the Xe1 and Xe4 cavities. However, no information on the trajectory of the ligand from the distal pocket to the Xe1 is available. Our results clearly show one possible path within the protein. In addition, although our data refer to a single trajectory, the local dynamics of the ligand in each cavity is sufficiently equilibrated to obtain local structural and thermodynamic information not accessible to crystallography. In particular, we show that the CO motion and the protein fluctuations are strictly correlated: free energy calculations of the migration between adjacent cavities show that the migration is not a simple diffusion but is kinetically or thermodynamically driven by the collective motions of the protein; conversely, the protein fluctuations are influenced by the ligand in such a way that the opening/closure of the passage between adjacent cavities is strictly correlated to the presence of CO in its proximity. The compatibility between time resolved crystallographic experiments and molecular dynamics simulations paves the way to a deeper understanding of the role of internal dynamics and packing defects in the control of ligand binding in heme proteins. PMID:15189882

  19. Interfacial Cu+ promoted surface reactivity: Carbon monoxide oxidation reaction over polycrystalline copper-titania catalysts

    DOE PAGES

    Senanayake, S. D.; Pappoe, N. A.; Nguyen-Phan, T. -D.; ...

    2016-10-01

    We have studied the catalytic carbon monoxide (CO) oxidation (CO+0.5O2 → CO2) reaction using a powder catalyst composed of both copper (5wt% loading) and titania (CuOx-TiO2). Our study was focused on revealing the role of Cu, and the interaction between Cu and TiO2, by systematic comparison between two nanocatalysts, CuOx-TiO2 and pure CuOx. We interrogated these catalysts under in situ conditions using X-ray Diffraction (XRD), X-ray Absorption Fine Structure (XAFS) and Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) to probe the structure and electronic properties of the catalyst at all stages of the reaction and simultaneously probe the surface statesmore » or intermediates of this reaction. With the aid of several ex situ characterization techniques including Transmission Electron Microscopy (TEM), the local catalyst morphology and structure was also studied. Our results show that a CuOx-TiO2 system is more active than bulk CuOx for the CO oxidation reaction due to its lower onset temperature and better stability at higher temperatures. Our results also suggests that a surface Cu+ species observed in the CuOx-TiO2 interface are likely to be a key player in the CO oxidation mechanism, while implicating that the stabilization of this species is probably associated with the oxide-oxide interface. Both in situ DRIFTS and XAFS measurements reveal that there is likely to be a Cu(Ti)-O mixed oxide at this interface. We discuss the nature of this Cu(Ti)-O interface and interpret its role on the CO oxidation reaction.« less

  20. Interfacial Cu+ promoted surface reactivity: Carbon monoxide oxidation reaction over polycrystalline copper-titania catalysts

    NASA Astrophysics Data System (ADS)

    Senanayake, Sanjaya D.; Pappoe, Naa Adokaley; Nguyen-Phan, Thuy-Duong; Luo, Si; Li, Yuanyuan; Xu, Wenqian; Liu, Zongyuan; Mudiyanselage, Kumudu; Johnston-Peck, Aaron C.; Frenkel, Anatoly I.; Heckler, Ilana; Stacchiola, Dario; Rodriguez, José A.

    2016-10-01

    We have studied the catalytic carbon monoxide (CO) oxidation (CO + 0.5O2 → CO2) reaction using a powder catalyst composed of both copper (5 wt.% loading) and titania (CuOx-TiO2). Our study was focused on revealing the role of Cu, and the interaction between Cu and TiO2, by systematic comparison between two nanocatalysts, CuOx-TiO2 and pure CuOx. We interrogated these catalysts under in situ conditions using X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to probe the structure and electronic properties of the catalyst at all stages of the reaction and simultaneously probe the surface states or intermediates of this reaction. With the aid of several ex situ characterization techniques including transmission electron microscopy (TEM), the local catalyst morphology and structure were also studied. Our results show that a CuOx-TiO2 system is more active than bulk CuOx for the CO oxidation reaction due to its lower onset temperature and better stability at higher temperatures. Our results also suggest that surface Cu+ species observed in the CuOx-TiO2 interface are likely to be a key player in the CO oxidation mechanism, while implicating that the stabilization of this species is probably associated with the oxide-oxide interface. Both in situ DRIFTS and XAFS measurements reveal that there is likely to be a Cu(Ti)-O mixed oxide at this interface. We discuss the nature of this Cu(Ti)-O interface and interpret its role on the CO oxidation reaction.

  1. SIMULTANEOUS DETECTION OF WATER, METHANE, AND CARBON MONOXIDE IN THE ATMOSPHERE OF EXOPLANET HR 8799 b

    SciTech Connect

    Barman, Travis S.; Konopacky, Quinn M.; Macintosh, Bruce; Marois, Christian

    2015-05-01

    Absorption lines from water, methane, and carbon monoxide are detected in the atmosphere of exoplanet HR 8799 b. A medium-resolution spectrum presented here shows well-resolved and easily identified spectral features from all three molecules across the K band. The majority of the lines are produced by CO and H{sub 2}O, but several lines clearly belong to CH{sub 4}. Comparisons between these data and atmosphere models covering a range of temperatures and gravities yield log mole fractions of H{sub 2}O between −3.09 and −3.91, CO between −3.30 and −3.72, and CH{sub 4} between −5.06 and −5.85. More precise mole fractions are obtained for each temperature and gravity studied. A reanalysis of H-band data, previously obtained at a similar spectral resolution, results in a nearly identical water abundance as determined from the K-band spectrum. The methane abundance is shown to be sensitive to vertical mixing and indicates an eddy diffusion coefficient in the range of 10{sup 6}–10{sup 8} cm{sup 2} s{sup −1}, comparable to mixing in the deep troposphere of Jupiter. The model comparisons also indicate a carbon-to-oxygen ratio (C/O) between ∼0.58 and 0.7, encompassing previous estimates for a second planet in the same system, HR 8799 c. Super-stellar C/O could indicate planet formation by core-accretion; however, the range of possible C/O for these planets (and the star) is currently too large to comment strongly on planet formation. More precise values of the bulk properties (e.g., effective temperature and surface gravity) are needed for improved abundance estimates.

  2. NIST Diffusion Data Center

    National Institute of Standards and Technology Data Gateway

    NIST Diffusion Data Center (Web, free access)   The NIST Diffusion Data Center is a collection of over 14,100 international papers, theses, and government reports on diffusion published before 1980.

  3. Parallel flow diffusion battery

    DOEpatents

    Yeh, Hsu-Chi; Cheng, Yung-Sung

    1984-08-07

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  4. Parallel flow diffusion battery

    DOEpatents

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  5. Method of removing nitrogen monoxide from a nitrogen monoxide-containing gas using a water-soluble iron ion-dithiocarbamate, xanthate or thioxanthate

    DOEpatents

    Liu, David K.; Chang, Shih-Ger

    1989-01-01

    A method of removing nitrogen monoxide from a nitrogen monoxide-containing gas, which method comprises: (a) contacting a nitrogen oxide-containing gas with an aqueous solution of water soluble organic compound-iron ion chelate of the formula: ##STR1## wherein the water-soluble organic compound is selected from compounds of the formula: ##STR2## wherein: R is selected from hydrogen or an organic moiety having at least one polar functional group; Z is selected from oxygen, sulfur, or --N--A wherein N is nitrogen and A is hydrogen or lower alkyl having from one to four carbon atoms; and M is selected from hydrogen, sodium or potassium; and n is 1 or 2, in a contacting zone for a time and at a temperature effective to reduce the nitrogen monoxide. These mixtures are useful to provide an unexpensive method of removing NO from gases, thus reducing atmospheric pollution from flue gases.

  6. Triton's Summer Sky of Methane and Carbon Monoxide

    NASA Astrophysics Data System (ADS)

    2010-04-01

    According to the first ever infrared analysis of the atmosphere of Neptune's moon Triton, summer is in full swing in its southern hemisphere. The European observing team used ESO's Very Large Telescope and discovered carbon monoxide and made the first ground-based detection of methane in Triton's thin atmosphere. These observations revealed that the thin atmosphere varies seasonally, thickening when warmed. "We have found real evidence that the Sun still makes its presence felt on Triton, even from so far away. This icy moon actually has seasons just as we do on Earth, but they change far more slowly," says Emmanuel Lellouch, the lead author of the paper reporting these results in Astronomy & Astrophysics. On Triton, where the average surface temperature is about minus 235 degrees Celsius, it is currently summer in the southern hemisphere and winter in the northern. As Triton's southern hemisphere warms up, a thin layer of frozen nitrogen, methane, and carbon monoxide on Triton's surface sublimates into gas, thickening the icy atmosphere as the season progresses during Neptune's 165-year orbit around the Sun. A season on Triton lasts a little over 40 years, and Triton passed the southern summer solstice in 2000. Based on the amount of gas measured, Lellouch and his colleagues estimate that Triton's atmospheric pressure may have risen by a factor of four compared to the measurements made by Voyager 2 in 1989, when it was still spring on the giant moon. The atmospheric pressure on Triton is now between 40 and 65 microbars - 20 000 times less than on Earth. Carbon monoxide was known to be present as ice on the surface, but Lellouch and his team discovered that Triton's upper surface layer is enriched with carbon monoxide ice by about a factor of ten compared to the deeper layers, and that it is this upper "film" that feeds the atmosphere. While the majority of Triton's atmosphere is nitrogen (much like on Earth), the methane in the atmosphere, first detected by

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

    DOEpatents

    Golden, Timothy Christopher; Farris, Thomas Stephen

    2008-11-18

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

  8. Cobalt promoted copper manganese oxide catalysts for ambient temperature carbon monoxide oxidation.

    PubMed

    Jones, Christopher; Taylor, Stuart H; Burrows, Andrew; Crudace, Mandy J; Kiely, Christopher J; Hutchings, Graham J

    2008-04-14

    Low levels of cobalt doping (1 wt%) of copper manganese oxide enhances its activity for carbon monoxide oxidation under ambient conditions and the doped catalyst can display higher activity than current commercial catalysts.

  9. Investigation of low temperature carbon monoxide oxidation catalysts. [for Spacelab atmosphere control

    NASA Technical Reports Server (NTRS)

    Jagow, R. B.; Katan, T.; Ray, C. D.; Lamparter, R. A.

    1977-01-01

    Carbon monoxide generation rates related to the use of commerical equipment in Spacelab, added to the normal metabolic and subsystem loads, will produce carbon monoxide levels in excess of the maximum allowable concentration. In connection with the sensitivity of carbon monoxide oxidation catalysts to poisoning at room temperature, catalysts for an oxidation of carbon monoxide at low temperatures have been investigated. It was found that platinum and palladium are the only effective room temperature catalysts which are effective at 333 K. Hopcalite was ineffective at ambient temperatures, but converted CO with 100 percent efficiency at 333 K. Poisoning tests showed the noble metal catalysts to be very sensitive, and Hopcalite to be very resistant to poisoning.

  10. Carbon monoxide toxicity. (Latest citations from the Life Sciences Collection data base). Published Search

    SciTech Connect

    Not Available

    1992-08-01

    The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains a minimum of 172 citations and includes a subject term index and title list.)

  11. Carbon monoxide toxicity. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    1996-10-01

    The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  12. Carbon monoxide toxicity. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    1995-10-01

    The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  13. Carbon monoxide toxicity. (Latest citations from the Life Sciences Collection database). NewSearch

    SciTech Connect

    Not Available

    1994-10-01

    The bibliography contains citations concerning the mechanism and clinical manifestations of carbon monoxide (CO) exposure, including the effects on the liver, cardiovascular, and nervous systems. Topics include studies of the carbon monoxide binding affinity with hemoglobin, measurement of carboxyhemoglobin in humans and various animal species, carbon monoxide levels resulting from tobacco and marijuana smoke, occupational exposure and the NIOSH (National Institute for Occupational Safety and Health) biological exposure index, symptomology and percent of blood CO, and intrauterine exposure. Air pollution, tobacco smoking, and occupational exposure are discussed as primary sources of carbon monoxide exposure. The effects of cigarette smoking on fetal development and health are excluded and examined in a separate bibliography. (Contains a minimum of 137 citations and includes a subject term index and title list.)

  14. 75 FR 3668 - Conditional Approval and Promulgation of State Implementation Plans; Ohio; Carbon Monoxide and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-22

    ... Monoxide and Volatile Organic Compounds AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed... the State's organic material and volatile organic compounds (VOC) \\1\\ emission control regulations... submitted revisions to a number of Ohio's VOC and organic material emission control regulations...

  15. FRACTIONAL PEARSON DIFFUSIONS.

    PubMed

    Leonenko, Nikolai N; Meerschaert, Mark M; Sikorskii, Alla

    2013-07-15

    Pearson diffusions are governed by diffusion equations with polynomial coefficients. Fractional Pearson diffusions are governed by the corresponding time-fractional diffusion equation. They are useful for modeling sub-diffusive phenomena, caused by particle sticking and trapping. This paper provides explicit strong solutions for fractional Pearson diffusions, using spectral methods. It also presents stochastic solutions, using a non-Markovian inverse stable time change.

  16. FRACTIONAL PEARSON DIFFUSIONS

    PubMed Central

    Leonenko, Nikolai N.; Meerschaert, Mark M.

    2013-01-01

    Pearson diffusions are governed by diffusion equations with polynomial coefficients. Fractional Pearson diffusions are governed by the corresponding time-fractional diffusion equation. They are useful for modeling sub-diffusive phenomena, caused by particle sticking and trapping. This paper provides explicit strong solutions for fractional Pearson diffusions, using spectral methods. It also presents stochastic solutions, using a non-Markovian inverse stable time change. PMID:23626377

  17. Four-electron deoxygenative reductive coupling of carbon monoxide at a single metal site

    NASA Astrophysics Data System (ADS)

    Buss, Joshua A.; Agapie, Theodor

    2016-01-01

    Carbon dioxide is the ultimate source of the fossil fuels that are both central to modern life and problematic: their use increases atmospheric levels of greenhouse gases, and their availability is geopolitically constrained. Using carbon dioxide as a feedstock to produce synthetic fuels might, in principle, alleviate these concerns. Although many homogeneous and heterogeneous catalysts convert carbon dioxide to carbon monoxide, further deoxygenative coupling of carbon monoxide to generate useful multicarbon products is challenging. Molybdenum and vanadium nitrogenases are capable of converting carbon monoxide into hydrocarbons under mild conditions, using discrete electron and proton sources. Electrocatalytic reduction of carbon monoxide on copper catalysts also uses a combination of electrons and protons, while the industrial Fischer-Tropsch process uses dihydrogen as a combined source of electrons and electrophiles for carbon monoxide coupling at high temperatures and pressures. However, these enzymatic and heterogeneous systems are difficult to probe mechanistically. Molecular catalysts have been studied extensively to investigate the elementary steps by which carbon monoxide is deoxygenated and coupled, but a single metal site that can efficiently induce the required scission of carbon-oxygen bonds and generate carbon-carbon bonds has not yet been documented. Here we describe a molybdenum compound, supported by a terphenyl-diphosphine ligand, that activates and cleaves the strong carbon-oxygen bond of carbon monoxide, enacts carbon-carbon coupling, and spontaneously dissociates the resulting fragment. This complex four-electron transformation is enabled by the terphenyl-diphosphine ligand, which acts as an electron reservoir and exhibits the coordinative flexibility needed to stabilize the different intermediates involved in the overall reaction sequence. We anticipate that these design elements might help in the development of efficient catalysts for

  18. Excess and unlike interaction second virial coefficients and excess enthalpy of mixing of (carbon monoxide + pentane)

    SciTech Connect

    McElroy, P.J.; Buchanan, S.

    1995-03-01

    Carbon monoxide and pentane are minor components of natural gas. The excess second virial coefficient of the mixture carbon monoxide + pentane has been determined at 299.5, 313.15, 328.15, and 343.15 K using the pressure change on mixing method. Unlike interaction second virial coefficients were derived and compared with the predictions of the Tsonopoulos correlation. The excess enthalpy of mixing was also estimated.

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

    NASA Technical Reports Server (NTRS)

    Peters, Leonard K.

    1988-01-01

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

  20. Carbon monoxide exposure in households in Ciudad Juárez, México.

    PubMed

    Montoya, Teresa; Gurian, Patrick L; Velázquez-Angulo, Gilberto; Corella-Barud, Verónica; Rojo, Analila; Graham, Jay P

    2008-03-01

    This study assessed exposure to carbon monoxide from gas and wood heater emissions in a sample of 64 households in peri-urban residential areas in Ciudad Juárez, Chihuahua, México. Indoor and outdoor carbon monoxide concentrations and temperatures were monitored for a continuous period of 1 week at 1 and 6-min intervals, respectively. The moving average carbon monoxide concentrations were compared to the World Health Organization (WHO) standards for carbon monoxide. Sixty-seven percent of households with gas heaters and 60% of households with wood heaters exceeded a health-based standard at some point during the monitoring. The difference between indoor and outdoor temperatures was modestly correlated with average carbon monoxide exposure (r=0.35, p-value <0.01). Heater type may be a stronger determinant of exposure, as households with a particular heater model (the El Sol FM-210) were significantly more likely to be among the more highly exposed households (odds ratio of 4.8, p-value of 0.02). A variety of health effects were pooled and found at elevated frequency in the households that exceeded the 8-h standard of 9ppm (odds ratio=5.1, p-value=0.031). These results highlight the need for further efforts to identify and mitigate potentially hazardous carbon monoxide exposures, particularly in moderate-income countries with cooler climates.