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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.
51

Transport phenomena of methanol and water in liquid feed direct methanol fuel cells /

Xu, Chao. January 2008 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (leaves 181-194). Also available in electronic version.
52

Convection-type PEM fuel cell control system performance testing and modeling

Hoy, Jeannette M. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains viii, 75 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 68-71).
53

Utilization of natural and supplemental biofuels for harvesting energy from marine sediments /

Nielsen, Mark E. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 121-128). Also available on the World Wide Web.
54

High-temperatire phase transitions on RbH₂PO₄

Martinez, Heber. January 2009 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
55

Framing ethanol a content analysis comparing national and regional media coverage of ethanol /

Smith, Courtney E. January 2008 (has links)
Thesis (M.A.)--Ball State University, 2008. / Title from PDF t.p. (viewed on Sept. 09, 2009). Includes bibliographical references (p. [65]-73).
56

Measuring the distribution of equity in terms of energy, environmental, and economic costs in the fuel cycles of alternative fuel vehicles with hydrogen pathway scenarios

Meyer, Patrick E. January 2010 (has links)
Thesis (Ph.D.)--University of Delaware, 2010. / Principal faculty advisor: Young-Doo Wang, School of Urban Affairs & Public Policy. Includes bibliographical references.
57

Refinement of numerical models and parametric study of SOFC stack performance

Burt, Andrew C. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xii, 148 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 119-124).
58

Coupled electrochemical and heat/mass transport characteristics in passive direct methanol fuel cells /

Chen, Rong. January 2007 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 191-207). Also available in electronic version.
59

Measuring the cost-effectiveness of idle reduction technologies in heavy-duty trucks

Prabhakar, Niranjani 07 January 2016 (has links)
The main objective of idle reduction devices is to reduce the amount of energy wasted by idling trucks, decrease exhaust emissions and save in fuel use and maintenance costs and vehicle life extension. To achieve reductions emissions from vehicle idling in heavy-duty trucks, strategies and actions have been employed through the use of various technologies, namely auxiliary power units (APUs), direct-fire heaters (DFHs), truck stop electrification (TSE) and advanced truck stop electrification (ATSE). Little quantitative data exists on the amount of emissions that are emitted by heavy-duty trucks during idling. In general, diesel engines emit less CO and hydrocarbons (HC) when compared to gasoline engines since fuel-lean mixtures tend to reduce CO and HC emissions. The purpose of this study is to conduct a systematic review that illustrates the status of data present in literature for costs and emissions reduced for APUs, DFHs, TSEs and ATSEs. From the review process, a cost calculator was devised from the synthesis of literature data to measure cost-effectiveness of these technologies in dollars per year per ton per year of emissions reduced over a 30 year investment period. Data on capital costs, maintenance and operational costs, and fuel costs were reported in order to calculate net present values, payback periods and fuel savings from each technology. Given the relevant data available from various studies that compute the efficiency of competing technologies, TSEs were the most cost-effective for the investor and the truck owner in regards to NOx emissions reduction. Cost-effectiveness measured for investors at $1,707.57 and $1,473.27 per ton of NOx reduced, and $16,799.91, $22,261.44, and $20,583.79 per ton of NOx reduced for truck owners. The calculator also served as a tool to illustrate insufficient data currently present in the body of literature. Limited quantitative data and unknown variability of costs as a function of time over the 30-year investment period was used to assess best practices. Thus, policymakers and other stakeholders can benefit from this review in order to conduct future studies that would enlighten greater understanding of data points from specifications of the operating context and devise more robust models for the sake of comparing these technologies based on impact and risk
60

The modelling and validation of one dimensional storage drying of woodchips for fuel

Pan, Ji-ning January 1993 (has links)
Since wood fuel when used sustainably provides an energy source that does not contribute to greenhouse warming, its use in future is likely to increase. Contractors prefer to chip trees and residues green to minimise power required and machinery wear. For non-specialised combustion systems the green woodchips should then be dried to increase their calorific value and to allow buffer storage without significant dry matter loss or the development of hazardous fungal spores. As the drying of wood chips has never been rigorously defined, a study was undertaken to determine the drying characteristics of green woodchips. A drying bin was built to simulate storage drying in one dimension. Data from three drying runs using spruce and birch whole tree provided data to validate a one-dimensional heat and mass transfer drying model converted from an existing grain drying routine. The specific energy consumption varied from 2.0 MJ/kg of moisture removed using unheated air during summer drying to 5.0 MH/kg during winter when dried with air warmed by 28°C. Dry matter loss in birch during drying and a period of two months cool storage was approximately 2%. Mean evaporation rate ranged from 1.9 kg/h in winter to 2.9 kg/h in summer. This gave a drying rate of 1% and 2.2% per day, inwinter and summer respectively. Hardwoodbirch released its moisture more readily than softwood Sitkaspruce. Airflow rates used ranged from 0.26-0.63 m<sup>3</sup>/s pertonne of dry matter. The dust levels on the woodchips ranged from 3.0 mg/m<sup>3</sup> ofair before drying up to 55 mg/m<sup>3</sup> of air after drying. The concentrations of colony forming units on woodchips ranged from2.0 X 10<sup>4</sup> cfu/m<sup>3</sup> of air before drying up to 8.0 X 10<sup>5</sup>cfu/m<sup>3</sup> of air after drying.

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