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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

Machine-learning-based modeling of biofuel engine systems with applications to optimization and control of engine performance

Wong, Ka In January 2017 (has links)
University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering
42

Biofuels in South Africa : factors influencing production and consumption

Chambers, David 01 April 2010 (has links)
Interest in the biofuels industry in South Africa is driven largely by high oil prices and a strain on energy resources and logistics. This report considers the development of the biofuels industry in its infancy in South Africa and the factors that need to be taken into account by the potential entrants into the market. It also considers the factors which will continue to affect the sustainability of the biofuels industry.A total of fifteen experts across the biofuels value chain as well as stakeholders, who are considered experts in their field, were approached directly to provide input into this research. Further information was gathered from three focus groups involving thirty five people, all of whom are involved in the evolving biofuels sector.The research has shown that out of a number of production factors and consumption factors identified, there a few key factors that can be seen to be largely influencing the further development of the biofuels industry. Similarly a few key factors which will influence the sustainability of the biofuels industry have been identified. / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted
43

The biota of the Swartkops Solar Saltworks and their potential for producing biofuels

De Lauwere, Monique Simone January 2012 (has links)
The Swartkops and Missionvale salinas in Port Elizabeth on the east coast of South Africa are surrounding by large informal settlements. The runoff from these settlements contributes largely to the eutrophication of the solar saltworks which in turn has an effect on the biotic functioning of the systems, ultimately affecting the quantity and quality of the salt produced. Inorganic nutrients and organic composition, as well as important biological groups were examined within the brine with the aim of comparing the current condition of the same salinas to their condition twelve years ago. Comparisons between inorganic nutrient concentrations and biological groups showed significantly higher inorganic nutrients, with chlorophyll a concentrations in the Swartkops salina in 2011 being significantly higher than in 2012 and the 1999 and 2011 chlorophyll a concentrations being significantly higher than 2012 in the Missionvale salina. Microalgae found in the salinas were cultured in four different growth media. Cells were stained with Nile Red fluorescent dye in order to estimate the extent of lipids production. Five of the most promising lipid producing species were isolated into a monoculture and grown at different salinities to establish the growth and lipid production in response to salinity. Halamphora coffeaeformis and Navicula sp. were found to be the best candidate species. They grew best at salinities between 50 and 70 psu and produced lipid vesicles consuming approximately 10 percent of the cell.
44

Evaluation of Storage Techniques to Preserve Fermentable Sugars from Sugar Beets for Ethanol Production

Vargas-Ramirez, Juan Manuel January 2012 (has links)
New sugar beet varieties may qualify as an advanced biofuel feedstock in the U.S., but new alternatives to conventional pile storage are necessary to preserve fermentable sugars and allow yearlong beet ethanol production. Fermentable sugar preservation was assessed in sugar beets stored under aerobic and anaerobic atmospheres and in raw thick juice stored at acidic (2≤ pH≤ 5) and alkaline (8≤ pH≤11) conditions. Aerobic storage of sugar beets at 4°C for 14 wk resulted in higher fermentable sugar retention (99± 4%) than at 25°C or anaerobic storage at 4° C and 25° C. Raw thick juice retained ≥ 99% of fermentable sugars at pH 3.5 and 9.5 and refractometric dissolved solids content of 64.5° Bx. The changes in fermentable sugars in raw thick juice stored for 24 wk at acidic and alkaline pH were modeled by response surface methodology. Although raw thick juice was stored successfully at acidic and alkaline pH, conditions for high-efficiency fermentation must be developed.
45

The uptake of metal ions by rhizopus arrhizus biomass /

Tobin, John M. (John Michael) January 1986 (has links)
No description available.
46

Energy production from poultry waste development and application of an economic model to compare various concepts /

Dickens, Ricky Everette. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2008. / Title from title page screen (viewed on Sept. 15, 2009). Thesis advisor: Atul Sheth. Vita. Includes bibliographical references.
47

Economic development in an era of global environmentalism sustainable development and environmental policy implementation in China /

Gao, Qingguo, January 1999 (has links)
Thesis (Ph. D.)--University of Tennessee, Knoxville, 1999. / Vita. Includes bibliographical references (leaves 214-219).
48

Estimating regional supply and delivered cost of forest and wood processing biomass available for bioenergy : a thesis submitted in partial fulfilment of the requirements for the degree of Masters in [i.e. Master of] Forestry Science in the University of Canterbury /

Robertson, Kimberly. January 2006 (has links)
Thesis (M. For. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 80-82). Also available via the World Wide Web.
49

Fermentative hydrogen production from wastewater by immobilized biomass

Li, Difu, 李迪夫 January 2007 (has links)
published_or_final_version / abstract / Civil Engineering / Master / Master of Philosophy
50

A socio-economic study of bioenergy crop adoption in North East Scotland : an agent-based modelling approach

Brown, Christopher January 2011 (has links)
Climate change has become the most important global environmental problem we face today. Agriculture, forestry and the land use sector not only contribute to national economies but also provide a source of greenhouse gas (GHG) emissions as well as a carbon store, contributing approximately 20% but removing about 16%. Energy crops and associated increases in soil carbon sequestration from different ground covers through various land management strategies are examples of approaches that could be adopted to reduce GHG emissions. A number of these options have an associated economic cost to the land manager and it is important to understand what is economically and socially viable by understanding the link between energy crop adoption and a range of socio-economic factors. Agent-based modelling (ABMs) has been identified as providing a promising approach to integrate social, economic and biophysical processes. In the past these areas of research have been mainly studied separately but now there is an urgent need to address these areas in a combined way. Economic rationalisation is fundamental to farmers’ decision-making, although not wholly representative and non-economic factors were identified. The estimated GHG mitigation potential of bioenergy crops at current adoption levels is modest when taking Scotland’s national GHG emissions into account, however, more significant when considering the agricultural sector in isolation. This contribution can only increase with improved management practices and policy designed to encourage adoption and improve energy security. This work will contribute to a greater understanding of bioenergy land use strategies. This project used North East Scotland as the case study, with raw data collated by questionnaire, however, conclusions drawn add to the broader understanding of the link between socio-economic activity, bioenergy adoption and GHG emissions.

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