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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.
21

Gas diffusion electrodes for environmental applications

Harrington, Tomas Seosamh January 1999 (has links)
No description available.
22

Computational and Experimental Studies of Catalytic Decomposition of H2O2 Monopropellant in MEMS-based Micropropulsion Systems

Widdis, Stephen 11 July 2012 (has links)
The next generation of miniaturized satellites (“nanosats”) feature dramatically reduced thrust and impulse requirements for purposes of spacecraft attitude control and maneuvering. E↵orts at the University of Vermont have concentrated on developing a MEMS-based chemical micropropulsion system based on a rocket grade hydrogen peroxide (HTP) monopropellant fuel. A key component in the micropropulsion system is the catalytic reactor whose role is to chemically decompose the monopropellant, thereby releasing the fuel’s chemical energy for thrust production. The present study is a joint computational and experimental design e↵ort at developing a MEMS-based micro-reactor for incorporation into a monopropellant micropropulsion system. Numerically, 0D and simplified 2D models have been developed to validate the model and characterize heat and mass di↵usion in the channel. This model will then be extended to a 2D model including all geometric complexities of the catalyst bed geometry with the goal of optimization. Experimentally, both meso and micro scale catalyst geometries have been constructed to prove the feasibility of using RuO2 nanostructures as an in situ in a microchannel.
23

Decay of radiolytically-generated peroxide in methanol

Wilson, Judith Walker January 1964 (has links)
Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / In work reported by Lichtin, Rosenberg, and Imamuras it was found that water added before irradiation of aerated methanol had a surprising effect on peroxide yields. In the absence of water, no hydrogen peroxide was produced during radiolysis, but in the presence of about 0.5 weight-percent water the yield of peroxide increased abruptly from zero to a plateau G value of 2.8. Attempts to reproduce these data were unsuccessful, however, and it was discovered that the observed effect of water on hydrogen peroxide yields is post-radiolytic in nature. Identical peroxide yields were produced during radiolysis of both dry methanol samples and samples to which water was added before radiolysis. In the dry samples, however, hydrogen peroxide was found to decompose with approximately first-order kinetics. Addition of water subsequent to irradiation inhibited decay. No significant change was noted in the concentration of radiolytically-generated formaldehyde during the period of peroxide decay. The average G(H2o2), obtained by extrapolation of the decomposition curve of radiolytically-generated hydrogen peroxide in dry methanol back to the time of the removal ofthe sample from the 60Co source, was 3.28 + 0.12. Half-decay times varied widely due to the variable dryness of the methanol. It was found that solutions of non-radiolytic hydrogen peroxide in dry methanol likewise underwent first-order decay. The rate of decomposition in these solutions could be accelerated by an increase in temperature or by subsequent radiolysis. The addition of formaldehyde was also found to accelerate peroxide decomposition, although no significant change was noted in the formaldehyde concentration. Methyl hydroperoxide was tentatively identified as a radiation product with a G value of about 0.2. Analysis of a radiolytic sample in which hydrogen peroxide had decomposed completely indicated that methyl hydroperoxide had not undergone similar decay. The nature of the hydrogen peroxide decomposition process is still unknown. Speculation concerning the decay inhibiting effect of water has been developed from several points of view: medium effects, specific interactions, and the possible effects of impurity. Influences of added sulfuric acid and methyl borate on radiolytic peroxide yields were also studied briefly. / 2031-01-01
24

Oxidation of biological molecules with bicarbonate-activated hydrogen peroxide and the decomposition of hydrogen peroxide catalyzed by manganese(II) and bicarbonate

Mitchell, Michael S. January 2004 (has links)
Thesis (M.S.)--University of Florida, 2004. / Title from title page of source document. Document formatted into pages; contains 60 pages. Includes vita. Includes bibliographical references.
25

The reaction of atomic oxygen with hydrogen peroxide.

Roscoe, John Miner. January 1968 (has links)
No description available.
26

The degrading effects of trace metals in the hydrogen peroxide bleaching of cotton

Snyder, Stuart David January 1957 (has links)
No description available.
27

Hydrogen peroxide treatment induced rectifying behavior of Au/n-ZnO contact

Gu, Qilin. January 2008 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.
28

The homogenous decomposition of hydrogen peroxide by plutonium (IV)

Elson, Robert E. January 1961 (has links)
Thesis (Ph.D.)--University of California, Berkeley, 1961. / "Chemistry, UC-4" -t.p. "TID-4500 (16th Ed.)" -t.p.
29

The role of antioxidants in the hydrogen peroxide-induced opacification of sheep lens : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science (Biochemistry) at Lincoln University /

Lei, Jie. January 2006 (has links)
Thesis (M. Sc.) -- Lincoln University, 2006.
30

Estudo comparativo da cor dental, in vivo, entre clareamentos sem aceleraçao, acelerado por LED e por laser, com análise dos resultados imediatos e a longo prazo

BRANCO, ELOISA P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:04Z (GMT). No. of bitstreams: 1 12797.pdf: 513559 bytes, checksum: 4b6e71bdbea803b32a3222d0b42f7b13 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo, Sao Paulo

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