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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.
31

Kinetics of production of acetylene from methane.

Leon, Humberto J January 1958 (has links)
The pyrolysis of methane diluted with nitrogen at 1200°C and 1.00 atm total pressure was investigated in a flow reactor made of alundum. The reaction is unaffected by a carbon surface but slightly catalyzed by an alundum surface. The initial rate of decomposition of methane is governed by -(dPCH₄/dt) = 5.7 PoCH₄ (atm/sec) for partial pressures ranging from 0.100 to 0.672 atm. The experimental pressure-time curves for methane up to 0.70 atm, acetylene up to 0.010 atm, hydrogen up to 0.30 atm, and time up to 0.05 sec were reproduced by the following equations: [ Formulas omitted ] An autocatalytic effect of acetylene, represented by the empirical equation (dPC₂H₂/dt )= (0.00586)(32.3) PCH₄ + [32.3 - 4.80(1+PoCH₄)]PC₂H₂ was observed in the initial stages of the reaction. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
32

INVESTIGATION OF ACTIVITY AND ACTIVE SITES OF Cu-CHA FOR METHANE ACTIVATION AND SELECTIVE CATALYTIC REDUCTION OF NOx REACTIONS

January 2020 (has links)
archives@tulane.edu / 1 / Aibolat Koishybay
33

An electron impact investigation of the fluorinated methanes /

Lougher, Edwin Henry January 1952 (has links)
No description available.
34

GASMAK2 model for longwall gob gas emission

Jin, Qinghua, January 2002 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains x, 93 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 71-72).
35

Dynamics of methane migration in marine hydrate systems examples from the Guaymas Transform, Blake Ridge, and Storegga landslide /

Nealon, Jeffrey W. January 2006 (has links)
Thesis (Ph. D.)--University of Wyoming, 2006. / Title from PDF title page (viewed on June 16, 2008). Includes bibliographical references.
36

Catalytic Combustion of Lean Methane on Commercial Palladium-Based Catalysts

Huang, Guangyu 06 1900 (has links)
Catalytic combustion provides us an efficient approach for the utilization and mitigation of methane, the major component of natural gas as well as an important greenhouse gas in global warming. From the research of catalytic combustion of methane, better understandings as well as solutions to the current methane-related problems can be obtained. This study investigates lean methane combustion on palladium-based catalysts. Catalysts activities were tested through ignition and extinction experiments. Several pretreatments and their influence were studied. Instrumental neutron activation analysis (INAA) and x-ray diffraction (XRD) were used as characterization tools for the catalysts. It was found that after being reduced, catalysts had stable and excellent abilities for methane conversion. However, these abilities were strongly compromised by additional water in the feeds. XRD results, combined with other testing results, implied that reduction produced the most active samples, while INAA revealed the real Pd concentrations of these catalysts. / Chemical Engineering
37

Investigation of feasibility of injecting power plant waste gases for enhanced coalbed methane recovery from low rank coals in Texas

Saugier, Luke Duncan 30 September 2004 (has links)
Greenhouse gases such as carbon dioxide (CO2) may be to blame for a gradual rise in the average global temperature. The state of Texas emits more CO2 than any other state in the U.S., and a large fraction of emissions are from point sources such as power plants. CO2 emissions can be offset by sequestration of produced CO2 in natural reservoirs such as coal seams, which may initially contain methane. Production of coalbed methane can be enhanced through CO2 injection, providing an opportunity to offset the rather high cost of sequestration. Texas has large coal resources. Although they have been studied there is not enough information available on these coals to reliably predict coalbed methane production and CO2 sequestration potential. The goal of the work was to determine if sequestration of CO2 in low rank coals is an economically feasible option for CO2 emissions reduction. Additionally, reasonable CO2 injection and methane production rates were to be estimated, and the importance of different reservoir parameters investigated. A data set was compiled for use in simulating the injection of CO2 for enhanced coalbed methane production from Texas coals. Simulation showed that Texas coals could potentially produce commercial volumes of methane if production is enhanced by CO2 injection. The efficiency of the CO2 in sweeping the methane from the reservoir is very high, resulting in high recovery factors and CO2 storage. The simulation work also showed that certain reservoir parameters, such as Langmuir volumes for CO2 and methane, coal seam permeability, and Langmuir pressure, need to be determined more accurately. An economic model of Texas coalbed methane operations was built. Production and injection activities were consistent with simulation results. The economic model showed that CO2 sequestration for enhanced coalbed methane recovery is not commercially feasible at this time because of the extremely high cost of separating, capturing, and compressing the CO2. However, should government mandated carbon sequestration credits or a CO2 emissions tax on the order of $10/ton become a reality, CO2 sequestration projects could become economic at gas prices of $4/Mscf.
38

Catalytic Combustion of Lean Methane on Commercial Palladium-Based Catalysts

Huang, Guangyu Unknown Date
No description available.
39

A comparison of methane dynamics between wetlands constructed for wastewater treatment and a natural sedgeland in South Australia /

Muller, Kerri. January 1900 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 2001. / "Figures, tables and the appendices appear in the volume II". Bibliography: leaves 130-152.
40

Probing the reaction mechanism of methyl coenzyme M reductase

Wang, Mi, Duin, Evert C., January 2008 (has links)
Thesis (Ph. D.)--Auburn University. / Abstract. Vita. Includes bibliographical references (p. 162-173).

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