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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.
531

A study of the remineralization of organic carbon in nearshore sediments using carbon isotopes /

McNichol, Ann P., January 1900 (has links)
Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 1986. / Vita. Includes bibliographical references (leaves 208-215).
532

Carbon capture and sequestration an option to buy time? /

Bauer, Nico. Unknown Date (has links) (PDF)
University, Diss., 2005--Potsdam.
533

The Action of carbon monoxide on sodium alcoholates alone and in the presence of salts of fatty acids ... /

Beatty, Wallace Appleton. January 1903 (has links)
Thesis (Ph. D.)--University of Chicago, 1902. / At head of title: The University of Chicago. Includes bibliographical references.
534

A study of remineralization of organic carbon in nearshore sediments using carbon isotopes /

McNichol, Ann P. January 1986 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1986. / "July 1986." Includes bibliographical references (p. 208-215).
535

Organic Carbon in the Subaqueous Soils of a Mesotidal Maine Estuary: An Investigation of Quantity and Source

Jespersen, Jennifer L. January 2006 (has links) (PDF)
No description available.
536

Production and Characterization of Carbon Structures Derived from Wood

Xie, Xinfeng January 2008 (has links) (PDF)
No description available.
537

Establishment of ureolytic biofilms and their influence on the permeability of pulse-flow porous media column systems

Wheeler, Laura Allison. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Robin Gerlach. Includes bibliographical references (leaves 220-225).
538

Investigating the flexibility of low-carbon power systems : wind variability and carbon capture

Gomez Martinez, Jonathan January 2017 (has links)
Increasing concerns about global warming have led to the exploration of options to abate CO2 emissions. Recent studies have identified the energy sector as the largest emitting source worldwide. Therefore, the transition towards low-carbon power systems has incorporated larger volumes of renewable generation. This situation is prompting the necessity of improving current strategies to operate power systems, as more variability is introduced in the decision making process. This thesis contributes in two aspects to manage the generation mix of future power systems. Firstly, it addresses the question of how many scenarios are enough to represent the variability of wind power. Results obtained indicate that a balance should be pursued between quality of solution and computational burden, as more scenarios does not significantly change the operational cost. Secondly, an original method to narrow down the number of scenarios is proposed. The so-called severe scenarios outperform typical reductions in the sense that fewer adjustments are required to the generation scheduling programme. Despite the growing renewable generation capacity, the operation of the electric system is likely to continue its reliance on thermal plants. Hence, the need to curb CO2 emissions in the existing thermal plants has led to the development of technologies such as carbon capture. The technical maturity of this technology is still in its early stages, since its application to thermal plants is under development. This thesis bridges the gap of current knowledge on carbon capture in three aspects. Firstly, it presents an innovative methodology to quantify the value of flexibility provided by carbon capture in the context of the British system. Secondly, the role of retrofitted generators as reserve providers is addressed. Finally, the synergy between carbon capture and wind power is assessed. The evaluation considers CO2 pricing, two strategies to manage CO2 capture rate, variability and different levels of wind integration.
539

N and C isotropic composition of different varieties of terrestrial diamonds and carbonado

Shelkov, Denis Alexander January 1997 (has links)
During the course of this research an instrument utilising combustion as a means of gas extraction capable of N, e, Ar and He analysis has been developed and the entire analytical procedure has been automated. N and e isotopic analysis has been performed on eclogitic and peridotitic diamonds (mainly from Yakutian kimberlites and the Roberts Victor kimberlite pipe). Diamonds with unusual (light and heavy relative to the peak of ol3e distribution of mantle diamonds) carbon isotopic signatures were considered for the research so that diamonds in the range of δ¹³C from -30‰ to + 2.8‰ were characterised for δ¹⁵N. The results together with data obtained previously by the others define fields for eclogitic and peridotitic diamonds on a plot of δ¹⁵N vs. δ¹³C. The model of mantle nitrogen and carbon evolution is discussed. A comprehensive comparison between carbonado and other known forms of microcrystalline diamond (framesites and shock diamonds) has been made for a number of parameters: N and e isotopic composition and N content; 4He content; morphology of the inner structure of diamond aggregates. It can be concluded that carbonado is generally similar to frame sites and all facts known about carbonado can be explained on the grounds of common mantle origin involving subducted carbon and nitrogen. Since extremely high 4He concentrations are encountered in carbonado this parameter is considered to be the most singular feature of this diamond variety and the radial distribution of 4He in single diamond crystals has been studied. A 4He content comparable with that in carbonado was found in the 30 J.lm skin of diamond crystals (up to 1.4 x 10⁻²) suggesting that carbonado could acquire high 4He concentration in the same geological processes as single diamond crystals and making carbonado indistinguishable from mantle diamonds in terms of He content. An additional result of the investigation is that the maximum of 4He diffusion coefficient for diamond at mantle P,T conditions can be estimated (≈4x10⁻²¹ ) from the 4He zoning identified in the interior of a diamond crystal from the Finsch kimberlite. A number of diamonds of impact origin from Popigai crater and Ebeliakh river placer deposits were studied for N, C and Ar isotopic compositions. It was concluded that diamonds from these two localities have resulted from separate impact events and that diamond aggregates studied are most probably consist of a mixture of different Ar and N carriers (e.g. two types of diamond grains).
540

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.

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