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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.
141

Über Bildung und Zersetzung des Kohlendioxyds im ultravioletten Licht

Sieper, Gustav. January 1916 (has links)
Univ., Diss.--Göttingen, 1916.
142

Miscibilities of certain tetrahalogen compounds of the fourth periodic group with anhydrous liquid sulfur dioxide,

Stephens, William Richmond, January 1929 (has links)
Thesis (Ph. D.)--University of Iowas, 1929. / Biography.
143

Stabilization of colloidal dispersions in supercritical carbon dioxide

Dickson, Jasper Lane, Johnston, Keith P., January 2005 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Keith P. Johnston. Vita. Includes bibliographical references.
144

Synthesis and evaluation of macroporous TiO2 composite photocatalyst /

Fan, Ka Ho. January 2006 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / On t.p. "2" is subscript. Includes bibliographical references. Also available in electronic version.
145

Optimal recovery of regional CO2 surface fluxes by data assimilation of anthropogenic and biogenic tracers

Campbell, Elliott. January 2007 (has links)
Thesis (Ph. D.)--University of Iowa, 2007. / Supervisors: Jerald Schnoor, Charles Stanier. Includes bibliographical references.
146

Carbon capture and sequestration an option to buy time? /

Bauer, Nico. Unknown Date (has links) (PDF)
University, Diss., 2005--Potsdam.
147

Sources of ambient Sulfur Dioxide (SO2) in the metro Atlanta area

Lowe, Miranda Jeanne. January 2007 (has links)
Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007. / Dr. James Mulholland, Committee Chair ; Dr. Armistead Russell, Committee Member ; Dr. Michael Bergin, Committee Member.
148

Photocatalytic Conversion of Carbon Dioxide to Methanol

Okpo, Emmanuel 01 January 2009 (has links)
The photocatalytic conversion of carbon dioxide (CO2) to methanol was investigated. The procedure for the carbon dioxide conversion was carried out using a small scale filter type photocatalytic reactor. In conducting the experiments, carbon dioxide mixed with water vapor was discharged into the photocatalytic reactor in the presence of a catalyst and light irradiation from a UV lamp for conversion to methanol. The catalyst that were used for the experiments were titanium dioxide (titania) and copper-loaded titania which were impregnated on a ceramic filter that was initially treated with gamma-alumina which was a good catalyst support for the catalyst. SEM, XRD and particle size analysis was performed as a means of characterization of the catalyst. The effect of the flow rate of carbon dioxide on the conversion process using a UV lamp with a wavelength of 254 nm was studied.
149

An investigation of reaction parameters for carbon dioxide utilisation

Silvestre Gonzalez, Vanessa January 2017 (has links)
Carbon dioxide emissions per year have risen exponentially. It is widely known the contribution of CO2 to global warming phenomena, so storage/utilisation of carbon dioxide has become a topical issue and an emerging research area. Despite the fact that utilization of CO2 waste would not solve the problem of the huge quantities going to the atmosphere every year as only less than 1% of it could be reused for the industry, recycled carbon dioxide presents itself as a possible cheap and accessible chemical feedstock. The challenge on recycling CO2 is to minimize energy and cost efficiency of any suitable reaction. On previous investigations the electrochemical synthesis of 5-membered cyclic carbonate from epoxides was accomplished under mild conditions and optimized (1 atm CO2 pressure, 60 mA constant current and 50 °C heating). In order to understand the mechanism of this electrochemical process a deep investigation on the variables of the synthesis of cyclic carbonates was carried out and is presented in this thesis. The variables studied include electrochemical system conditions (application of current through Cu/Mg electrodes, electrodes connected on a closed circuit system with no current, an open circuit system where electrodes were there was no connection between them, and reactions without electrodes), temperature of reaction, solvent screening, catalysts, epoxide substituents, concentration of species and ratio of reactants. As a result of the variables optimization, a new, cheap, simple and relatively fast method (5 to 24 hours of reaction time) for cyclic carboxylation of epoxides with CO2 at atmospheric pressure in acetonitrile in the presence of ammonium salt (TBAI) at mild temperatures (50-75 °C) has been developed and improved. The concentration of the reactants, especially of the epoxide, was found to be the most important factor on the success of the reaction. The new reaction conditions also allow converting epoxides to carbonates without the help of any cocatalyst or electrochemical system obtaining excellent yields (50-100%) with the important saving on cost and energy of co-catalyst synthesis and recovery. Chlorostyrene oxide (1 M) reacted almost completely (94%) after 24 hours with TBAI (1 M), in 1 mL of acetonitrile at 75 °C and 1 atm pressure of CO2. Epoxide carboxylation under neat conditions was feasible, producing 44% of chlorostyrene carbonate from chlorostyrene oxide in the presence of TBAI at 75 °C and 1 atm pressure of CO2.
150

THERMODYNAMIC EVALUATION OF PROCESSES FOR HYDROGEN PRODUCTION FROM CARBONACEOUS FUEL

Kaini, Bhanu 01 December 2010 (has links)
This research work presents the thermodynamic analysis of hydrogen production using steam methane reforming process at different conditions. The model is developed using HSC 4.1 software and spreadsheet. Methane is chosen to represent the carbonaceous fuel and steam methane reforming process (once through and cyclic) for hydrogen production is analyzed based on 1st law and 2nd law of thermodynamics i.e., energetic and exergetic efficiencies. The mass, energy and exergy analysis of each step is done. The optimal condition for production of maximum hydrogen is found using CO2 removal agent and O2 transfer compound. The efficiency is calculated as a function of steam content, temperature and amount of CO2 removal agent and O2 transfer compound. The pressure is kept constant at one atmosphere. Operating temperature, CaO loading, Fe2O3 loading and H2O content is determined from the once through process. It is found that the maximum H2 production is with the cyclic process. Maximum H2 produced in cyclic process with CaO & Fe2O3 loadings is 99.2%. Also CO2 content is comparatively lower in cyclic process. Theoretical efficiencies can be used to compare with the available data which will help to minimize the losses in the process. The results can be used as a baseline for the design of H2 production technology. The main aim of this research is to develop a thermodynamic protocol for evaluating hydrogen production processes.

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