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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

The cardiovascular and respiratory responses of dogs to lethal concentrations of carbon monoxide /

Coburn, Kenneth R. January 1960 (has links)
No description available.
72

Investigation of the reactivity of [HM?(CO)??]? (M = Ru, Os) clusters : kinetics of ¹³CO exchange, effects of ion pairing, and the relationship between the ¹³CO exchange and the catalysis of the water-gas shift reaction /

Payne, Martin William January 1987 (has links)
No description available.
73

Adsorption studies at reaction conditions: reactor development and evaluation for rapid transient simultaneous pressure, temperature and gas composition measurements of binary carbon monoxide and hydrogen adsorption over a nickel catalyst /

Buchanan, Donald William January 1979 (has links)
No description available.
74

The generation of carbon monoxide in compartment fires

Gottuk, Daniel T., 1967- 06 June 2008 (has links)
For the purpose of fire analysis and fire safety engineering, the development of empirical correlations for major species yields in compartment fires has become an important priority due to the inability to calculate these quantities from first principles. Studies of simplified upper layer environments have shown that major species production rates can be correlated with the equivalence ratio in what is known as the Global Equivalence Ratio concept (GER). Due to the simplification in these past experiments, it was not known if the GER concept was valid for compartment fires. Therefore, there was a need to determine if correlations existed between major species yields and the equivalence ratio for actual compartment fires. Since the flow of toxic gases from a room poses a hazard to building occupants, it was also important to determine if correlations for CO yield outside of a compartment on fire exist, particularly when external burning occurs. A 2.2 m³ test compartment was used to investigate the burning of four fuels (hexane, PMMA, spruce and flexible polyurethane foam) in compartment fires. The test compartment was specially designed with a two-ventilation path system which allowed the direct measurement of the plume equivalence ratio (the ratio of the fuel volatilization rate to the air entrainment rate normalized by the stoichiometric fuel-to-air ratio). Empirical correlations between the upper layer yield of major species and the plume equivalence ratio were shown to exist The results reveal that the production of CO is primarily dependent on the compartment flow dynamics (i.e., the equivalence ratio) and upper layer temperature. A chemical kinetics study indicated that increased compartment temperature affects upper layer species yields in two ways 1) the generation of species in the plume is changed and 2} oxidation of post-flame gases in the layer is affected. The correlations developed in the compartment fifes were qualitatively similar to those developed by Beyler for simplified upper layer environments. However, quantitative differences existed and are explained by the temperature effect. The species yields downstream of hexane compartment flues were investigated and compared to upper layer yields. Results showed that downstream CO yields can be correlated to the plume equivalence ratio when taking into account the occurrence of external burning. When sustained external buning occurred for equivalence ratios greater than 1.7, downstream CO yields were reduced to 10 to 25 percent of the upper layer value. Results are very encouraging in indicating that an ignition criterion based on lean flammability limits is useful in predicting the flammability of upper layer gases in compartment fires. An ignition index value of 1.3 indicated the occurrence of sustained external burning and, thus, a reduction of CO, for the hexane fires studied. / Ph. D.
75

Wearable Pulse Oximetry in Construction Environments

Forsyth, Jason B. 16 April 2010 (has links)
The goal of this project was to determine the feasibility of non-invasively monitoring the blood gases of construction workers for carbon monoxide exposure via pulse oximetry. In particular, this study sought to understand the impact of motion artifacts caused by the worker's activities and to determine if those activities would prevent the blood gas sensor from detecting the onset of carbon monoxide poisoning. This feasibility study was conducted using a blood oxygen sensor rather than a blood carbon monoxide sensor for several reasons. First, blood gas sensors that measure blood carbon monoxide are not readily available in suitable physical form factors. Second, sensors for blood oxygen and blood carbon monoxide operate on the same physical principles and thus will be affected in the same way by worker motions. Finally, using a blood oxygen sensor allowed the study to be conducted without exposing the human subjects to carbon monoxide. A user study was conducted to determine the distribution of motion artifacts that would be created during a typical work day. By comparing that distribution to a worst-case estimate of time to impairment, the probability that helmet will adequately monitor the worker can be established. The results of the study show that the helmet will provide a measurement capable of warning the user of on setting carbon monoxide poisoning with a probability greater than 99%. / Master of Science
76

Impact and nature of open metal sites: a water and carbon monoxide adsorption study on MOF-74 isostructural MOFs

Flemming, Christine Juliette Jane 06 July 2012 (has links)
In this work the magnesium, zinc, nickel and cobalt MOFs of the MOF-74 isostructural family are used to probe metal-dependent adsorbate interactions with water and with carbon monoxide because of their ability to generate open metal sites upon activation. An isostructural family is used so that the only variable from one MOF to another is the metal incorporated into the framework. For water adsorption isotherms with humidities up to 90%, the observed trend at 298K and 1 bar is Mg-MOF-74 > Zn-MOF-74 > Co-MOF-74 > Ni-MOF-74. This observed trend is due to Lewis acid-base interactions. When the weight effect is removed, differences are still observed, especially below 40% relative humidity, thereby confirming that there is a metal effect. These studies revealed that PXRD alone cannot indicate the level of structural decomposition and that none of the four isostructures fully retain their structural integrity on exposure to humidified air because of microstrain and/or the presence of oxygen; more studies examining the extent of structural decomposition need to be undertaken. For carbon monoxide adsorption the general observed trend for P < 4 bar and temperatures of 298, 313 and 333K is Co-MOF-74 > Ni-MOF-74 > Zn-MOF-74 > Mg-MOF-74. This trend is based on π-backbonding interactions. Here again, differences remain after removal of the weight effect, confirming the metal dependence. Notably, Co-MOF-74 has the highest CO loading at 298K and 1 bar reported so far. Both the Toth and Virial Isotherms were used to fit the CO adsorption data followed by the use of the Clausius-Clapeyron equation to find the isosteric heats of adsorption, qst. The results from the Toth isotherm are more reliable and showed that qst remains constant as loading increases for Mg-MOF-74, decreases for Zn-MOF-74 and increases with loading for Co-MOF-74 and Ni-MOF-74; Ni-MOF-74 had the highest heat of adsorption at all loadings. It appears that using the Clausius-Clapeyron equation to calculate qst is an inappropriate method for Ni-MOF-74 so other methods such as calorimetry are recommended. It is also recommended to model the data of all the MOFs with other isotherm models such as Sips equation and to investigate the possibility of chemisorption for the cobalt and nickel isostructures. Finally, Henry’s constant results reveal that Ni-MOF-74 has the highest affinity for CO at low coverages.
77

Nasal airway nitric oxide : methodological aspects and influence of inflammation /

Palm, Jörgen, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 5 uppsatser.
78

Air quality monitoring with polar-orbiting hyperspectral infrared sounders : a fast retrieval scheme for carbon monoxide

Smith, Nadia 07 October 2014 (has links)
D.Phil. (Geography) / The Infrared Atmospheric Sounding Interferometer (lASI), operational in polar-orbit since 2006 on the European MetOp-A satellite, is the most advanced of its kind in space. It has been designed to provide soundings of the troposphere and lower stratosphere at nadir in a spectral interval of 0.25 em" across the range 645-2 760 em". Fine spectral sampling such as this is imperative in the sounding of trace gases. Since its launch, the routine retrievals of greenhouse, species from IASI measurements have made a valuable contribution to atmospheric chemistry studies at a global scale. The main contribution of this thesis is the development of a new trace gas retrieval scheme for IASI measurements. The goal was to improve on the global operational scheme in terms of the algorithm complexity, speed of calculation and spatial resolution achieved in the final solution. This schemedirectly retrieves column integrated trace gas densities at single field-of-view (FOV) from IASI measurements within a 10% accuracy limit. The scheme is built on the Bayesian framework of probability and based on the assumption that the inversion of total column values, as apposed to gas profiles, is a near-linear problem. Performance of the retrieval scheme is demonstrated on simulated noisy measurements for carbon monoxide (CO). Being a linear solution, the scheme is'highly dependent on the accuracy of the a priori. A statistical estimate of the a priori was computed using a principal component regression analysis with 50 eigenvectors. The corresponding root-mean-square (RMS) error of the a priori was calculated to be 9.3%. In general terms, the physical retrieval improved on the a priori, and sensitivity studies were performed to demonstrate the accuracy and stability of the retrieval scheme under a numberof perturbations. A full system characterization and error analysis is additionally preformed to elicidate the nature of this complex problem. The hyperspectral IASI measurements introduce a significant correlation error in the retrieval. The Absorption Line Cluster (ALC) channel selection method was developed in this thesis, to address the correlation error explicitly. When a first neighbour correlation factor of 0.71 is assumed in the measurement error covariance for the clusters of ALC channels, then most of the correlation error is removed in the retrieval. In conclusion, the total column trace gas retrieval scheme developed here is fast, simple, intuitive, transparent and robust. These characteristics together make it highly suitable for implementation in an operational environment intended for air quality monitoring on a regional scale.
79

Influence of solvent on the infared spectrum of carbon monoxide adsorbed on platinum electrodes

Feltovich, Susanne D. 29 September 2009 (has links)
The behavior of adsorbed carbon monoxide on platinum was studied using potential difference infrared spectroscopy. Three solvents and three electrolytes were chosen, and data gathered at both high and low adsorbate coverages. The rate of change of IR peak position with applied potential, the Stark tuning rate, was used as an indicator of the local electric field strength at the interface. It was determined that neither solvated cation size nor bulk dielectric constant accounts for the changes in Stark tuning rate with different solvents. / Master of Science
80

A Telemetry System for Firefighters

Uprety, Sandip, Caglio, Joseph, Ho, Michelle, Chio, Chi Hou, Mckeefery, Stephanie, Goh, Jae Hyok 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In this project, a telemetry system is implemented to save firefighters from potential danger in their working environment. Each Firefighter has a "node" or "unit" attached to them which contains temperature, oxygen, and carbon-monoxide sensors, and a transceiver. Each node constantly transmits data collected by the sensors to a central "base station." The base station consists of a laptop which is monitored by the Fire Chief at a safe distance from the scene, and it displays gas levels. The base station monitors the sensor readings, and sets off an alarm locally and also at the node if a reading has reached a predetermined critical value.

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