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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.
41

Composite low temperate hydrogen storage material on the basis of iron-titanium alloy / synthesis and structure.

Onyegbule, Nkele. January 2006 (has links)
<p>It is widely believed that hydrogen will, within a few years, become the means of storing and transporting energy. The reason is the depletion of hydrocarbons and the relatively facile production of hydrogen from various renewable sources of energy. Hydrogen can be combusted in an efficient way in a fuel cell with water as emission product. The overall goal of the project was to deevlop the knowledge base for solid-state hydrogen storage technology suitable for stationary and mobile applications. The aim of this research was to develop a novel composite hydrogen storage material with high wt% storage capacity, high intrinsic safety, appropriate thermodynamics, high mechanical strength, reversibility of the system and fast kinetics based on a well known &quot / low temperature&quot / intermetallic alloy (Ti/Fe) as the core.</p>
42

Design and operation of a tubular photobioreactor for microalgea production

Wable, Olivier 08 1900 (has links)
No description available.
43

Composite low temperate hydrogen storage material on the basis of iron-titanium alloy / synthesis and structure.

Onyegbule, Nkele. January 2006 (has links)
<p>It is widely believed that hydrogen will, within a few years, become the means of storing and transporting energy. The reason is the depletion of hydrocarbons and the relatively facile production of hydrogen from various renewable sources of energy. Hydrogen can be combusted in an efficient way in a fuel cell with water as emission product. The overall goal of the project was to deevlop the knowledge base for solid-state hydrogen storage technology suitable for stationary and mobile applications. The aim of this research was to develop a novel composite hydrogen storage material with high wt% storage capacity, high intrinsic safety, appropriate thermodynamics, high mechanical strength, reversibility of the system and fast kinetics based on a well known &quot / low temperature&quot / intermetallic alloy (Ti/Fe) as the core.</p>
44

Hydrogeology, hydrochemistry and isotope hydrology of Palm Valley, Central Australia

Wischusen, John David Henry, School of Biological, Earth & Environmental Sciences, UNSW January 2005 (has links)
The Palm Valley oasis in arid central Australia is characterised by stands of palm trees (Livistona mariae). How these unique plants, separated by nearly a 1000 kilometres of arid country from their nearest relatives persist, has long fascinated visitors. Defining the hydrogeology of the Hermannsburg Sandstone, a regionally extensive and thick Devonian sequence of the Amadeus Basin that underlies Palm Valley, is the major thrust of investigation. Appraisal of drilling data shows this aquifer to be a dual porosity fractured rock aquifer which, on a regional scale, behaves as a low permeability, hydraulically continuous resource. Groundwater is low salinity (TDS &lt1000 mg/L) and bicarbonate rich. Slight variations in cation chemistry indicate different flow paths with separate geochemical histories have been sampled. Stable isotope (????H, ???????O) results from Palm Valley show groundwater to have a uniform composition that plots on or near a local meteoric water line. Radiocarbon results are observed to vary from effectively dead (&lt 4%) to 87 % modern carbon. To resolve groundwater age beyond the radiocarbon window the long lived radioisotope 36Cl was also used. Ratios of 36Cl/Cl range from 130 to 290 x 10-15. In this region atmospheric 36Cl/Cl ratio is around 300 x 10-15. Thus an age range of around 300 ka is indicated if, as is apparent, radioactive decay is the only significant cause of 36Cl/Cl variation within the aquifer. A review of previous, often controversial, 36Cl decay studies shows results are usually ambiguous due to lack of certainty when factoring subsurface Cl- addition into decay calculations. Apparently, due to the thickness of the Hermannsburg Sandstone, no subsurface sources of Cl- such as aquitards or halites, are encountered along groundwater flow paths, hence the clear 36Cl decay trend seen. The classic homogenous aquifer with varying surface topography, the &quotToth&quot flow model, is the simplest conceptual model that need be invoked to explain these isotope data. Complexities, associated with local topography flow cells superimposed on the regional gradient, signify groundwater with markedly different flow path lengths has been sampled. The long travel times (&gt 100 ka) indicate groundwater discharge would endure through arid phases associated with Quaternary climate oscillations. Such a flow system can explain the persistence of this arid zone groundwater-dependent ecosystem and highlight the possibility that Palm Valley has acted as a flora refuge since at least the mid- Pleistocene.
45

Iodine speciation in the Yarra River estuary /

Jianping, Lin. January 1992 (has links)
Thesis (M.Sc.)--University of Melbourne, 1992. / Typescript (photocopy). Bibliography: leaves 110-115.
46

Impact of land reclamation on hydrogeochemical processes in coastal aquifer systems a case study in Shenzhen, China /

Chen, Kouping. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.
47

Water chemistry characterization and component performance of a recirculating aquaculture system producing hybrid striped bass /

Easter, Christopher, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 134-143). Also available via the Internet.
48

Speciation dynamics in the freshwater environment : unifying concepts in metal speciation and bioavailability /

Murimboh, John David, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2002. / Includes bibliographical references. Also available in electronic format on the Internet.
49

Impact of land reclamation on hydrogeochemical processes in coastal aquifer systems : a case study in Shenzhen, China /

Chen, Kouping. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available online.
50

Characterization of dissolved organic matter (DOM) in southeastern North Carolina rainwater a ¹HNMR approach /

Dixon, Joshua L. January 2008 (has links) (PDF)
Thesis (M.S.)--University of North Carolina Wilmington, 2008. / Title from PDF title page (viewed May 27, 2009) Includes bibliographical references (p. 49-51)

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