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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.

The Rate inhibiting effect of water as a product on reactions catalysed by cation exchange resins formation of mesityl oxide from acetone as a case study /

Du Toit, Elizabeth Louisa. January 2003 (has links)
Thesis (M. Sc.)(Chemical Eng.)--University of Pretoria, 2003. / Bibliography included.

Coupling reactions and separations in propane-organic-aqueous tunable solvent systems

Husain, Zainul Abideen. January 2009 (has links)
Thesis (M. S.)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Eckert, Charles; Committee Co-Chair: Liotta, Charles; Committee Member: Meredith, Carson. Part of the SMARTech Electronic Thesis and Dissertation Collection.

The efficacy of acetone defatting as an adjunct to cutaneous disinfection of catheter sites in total parenteral nutrition

Nelson, Karen Hall. January 1979 (has links)
Thesis (M.S.)--University of Wisconsin-Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 26-29).

Proton spin-lattice relaxation in acetone-water mixtures

Sharma, Surendra Nath January 1962 (has links)
The work reported here is concerned with the measurement of the spin-lattice relaxation of protons in water, acetone, a D₂O - acetone mixture and various aqueous solutions of acetone. The theory to account for the decay rates has been outlined for a general case and has been applied in particular to acetone-water mixtures. The NMR technique has been described briefly. Temperature dependences of T₁ for all solutions have been investigated. It has been found that the relaxation in mixtures are slower than predicted by the theory. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

A reassessment of the production of acetone and butanol by Clostridium acetobutylicum in continuous culture

Clarke, Kim Gail January 1987 (has links)
Bibliography: pages 154-195. / The production of acetone and butanol by Clostridium acetobutylicum P 262 was studied in continuous culture under conditions where the nutrients were present in excess of the requirements and the cell growth was limited by the products formed during the fermentation. This system differs from most continuous culture systems used to obtain solvent production where the limitation of a specific nutrient was utilised to limit the cell growth.

The oxidation of isopropyl alcohol, acetone, and butyl compound by neutral and alkaline potassium permanganate

Sefton, Lily Bell, January 1921 (has links)
Thesis (Ph. D.)--Ohio state University, 1921.

CNDO/2 Calculations on Low-Lying Electronic States of Acetone and Formaldehyde

White, Gerald 09 1900 (has links)
<p> Various low-lying electronic states of formaldehyde and acetone have been investigated, using molecular orbital calculations, to determine their involvement in the photochemical system. The potential energy surfaces of these states were calculated using the CND0/2. </p> <p> The results of this study show that the decomposition of formaldehyde to molecular products H2 and CO (process II) occurs via the ground state; the potential surface of this process was studied using configuration interaction methods. </p> <p> The process leading to radical products in both acetone and formaldehyde (process I) can arise either directly from the singlet and triplet (n,π*) states via a reaction path of no symmetry, or by crossing to the 3 (π,π*) state should Cs symmetry be maintained. The ground state is the only other state correlating with radical products. </p> / Thesis / Master of Science (MSc)

Improved performance of alkaline batteries via magnetic modification and voltammetric detection of breath acetone at platinum electrodes

Motsegood, Perry Nelson 01 July 2012 (has links)
Incorporation of magnetic microparticles (~ 1 um) at electrode structures increases electron transfer e¢ ciency, observed as increased current, for multiple electrochemical systems. Current increases occur with magnetic field. Inclusion of magnetic materials into the cathode matrix of alkaline MnO2 batteries requires the materials to be stable in the strong base electrolyte, typically 6 to 9 M KOH. Samarium cobalt magnetic particles sustain strong permanent magnetic fields and are stable in base without surface modification. Studies were undertaken at fast (C/2), moderate (C/3), and slow (C/5) constant current discharges. Here, alkaline MnO2 batteries generated increased power and energy when magnetic microparticles are incorporated into the cathode of the battery. Because of anode limitations in the battery, total coulombic output is not increased for the first electron discharge, but the available power and energy is significantly higher compared to nonmagnetic batteries at voltages above 0.9V. Constant current discharge curves of magnetic batteries demonstrate higher voltages than nonmagnetic batteries at a given time, which translates to greater power output. This effect is also observed by electrochemical impedance spectroscopy, where charge transfer resistance is less for magnetically modified cells. This work also developed voltammetric measurement protocols for acetone concentration collected in the liquid and vapor phase and measured in solution. Acetone on the breath is an indicator for physiological dysregulation. Measurements are demonstrated for acetone concentrations across the human physiological range, 1 uM to 10 mM at platinum electrodes in 0.5 M H2SO4. Effects arise through adsorption of acetone from the gas phase onto a platinum surface and hydrogen in acidic solution within the voltammetric butterfly region. The protocol is demonstrated to yield breath acetone concentration on a human subject within the physiological range and consistent with ketone urine test strip.

Effects of polycyclic musks and bisphenol A on the settlement and metamorphosis on sponge, Spongia ceylonensis

Chen, Shiang-Ting 05 September 2011 (has links)
Sponge population partly depends on larval recruitment. Environmental factors, e.g. light, salinity, pH and temperature, chemical factors and pollution may influence larval settlement and metamorphosis. In this study, the effects of galaxolide¡]HHCB¡^¡Btonalide¡]AHTN¡^and bisphenol A¡]BPA¡^on the settlement and metamorphosis of an intertidal sponge ¡]Spongia ceylonensis¡^ were examined. The experiments included LC50 test, effects of solvent, HHCB, AHTN and BPA on sponge settlement and metamorphosis. In the LC50 tests, the 96 hr¡VLC50 value of HHCB and AHTN all greater than 1.00 mg/L, and the 96 hr¡VLC50 of BPA was 0.58 mg/L. Acetone concentration (1.00 mg/L ) in this study didn¡¦t affect sponge settlement and metamorphosis. Effect of HHCB and AHTN on sponge settlement and metamorphosis concentrations of 0.13, 0.25, 0.50 and 1.00 mg/L was insignificant. In contrast, the settlement rate was decrease by 20 % at treatment of 1.00 mg/L BPA. The metamorphosis rates were also decrease by 20 % and 80 % at concentrations of 0.50 mg/L and 1.00 mg/L BPA. In conclusion, the toxicity of AHTN was greater than that of HHCB to sponge settlement and metamorphosis.

Coupling reactions and separations in propane-organic-aqueous tunable solvent systems

Husain, Zainul Abideen 29 June 2009 (has links)
Developing environmentally sustainable processes are essential to improving the quality of life for future generations. In addition to reducing our impact on the environment, we must design processes to be both economical and safe. A large component of any chemical process is the solvents used to dissolve the reactants and extract the products. The research presented here focuses on coupling efficient homogeneous reactions with simple heterogeneous separations using propane-organic-aqueous tunable solvent systems. Our tunable solvents undergo a phase separation upon application of propane pressure to a fully miscible mixture of water and an organic solvent. The propane based tunable systems detailed here eliminate carbonic acid formation and reduce productphase contamination when compared with the equivalent CO2 based solvent systems previously studied. Additionally, we eliminate the need to use buffers and thus solids handling equipment is not needed.

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