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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.
111

Characterisation of the regeneration performance of rigid ceramic filters

Koch, Dietrich January 1996 (has links)
No description available.
112

Ice nucleation on uncoated and coated atmospheric mineral dust particles

Eastwood, Michael Logan 11 1900 (has links)
An optical microscope coupled to a flow cell was used to investigate ice nucleation on five atmospherically relevant mineral dusts at temperatures ranging from 233 to 247 K. Kaolinite and muscovite particles were found to be efficient ice nuclei in the deposition mode, requiring relative humidities with respect to ice (RHi) below 112% in order to initiate ice crystal formation. Quartz and calcite particles, by contrast, were poor ice nuclei, requiring relative humidities close to water saturation before ice crystals would form. Montmorillonite particles were efficient ice nuclei at temperatures below 241 K, but poor ice nuclei at higher temperatures. In several cases, there was a lack of quantitative agreement between these data and previously published work. This can be explained by several factors including mineral source, particle size, observation time and surface area available for nucleation. Heterogeneous nucleation rates (Jhet) were calculated from the onset data. Jhet values ranged from 60 to 1100 cm-²s-¹ for the five minerals studied. These values were then used to calculate contact angles (θ) for each mineral according to classical nucleation theory. The contact angles measured for kaolinite and muscovite ranged from 6 to 12º; for quartz and calcite the contact angles were much higher, ranging from 25 to 27º. The contact angles measured for montmorillonite were less than 15º at temperatures below 241 K, and above 20º at higher temperatures. The reported Jhet and θ values may allow for a more direct comparison between laboratory studies and can be used when modeling ice cloud formation in the atmosphere. The roles of H₂SO₄ and (NH4)₂SO₄ coatings on the ice nucleating properties of kaolinite were also investigated. Onset data was collected for H₂SO₄ coated and (NH4)₂SO₄ coated kaolinite particles at temperatures ranging from 233 to 247 K. In contrast to uncoated kaolinite particles, which were effective ice nuclei, H₂SO₄ coated particles were found to be poor ice nuclei, requiring relative humidities close to water saturation before nucleating ice at all temperatures studied. (NH4)₂SO₄ coated particles were poor ice nuclei at 245 K, but effective ice nuclei at 236 K.
113

Climate analysis and long range forecasting of dust storms in Iraq

Crook, Jacquelyn C. January 2009 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, June 2009. / Thesis Advisor(s): Murphree, Tom ; Stone, Rebecca. "June 2009." Description based on title screen as viewed on July 13, 2009. DTIC Identifiers: Climatology, precipitation rate, statistical forecasting, El Nino, La Nina. Author(s) subject terms: Iraq, Climatology, Long Range Forecast, Composite Analysis Forecast (CAF), Dust, Military Operations, Climate; Seasonal Forecast; Shamal; El Nino; La Nina; Precipitation Rate; Statistical Forecast. Includes bibliographical references (p. 59-61). Also available in print.
114

Empirical and modeling studies on the physical and radiative properties of windblown dust over the Columbia Plateau

Sundram, Irra T. Mohana, January 2005 (has links) (PDF)
Thesis (Ph. D.)--Washington State University. / Includes bibliographical references.
115

Sampling cyclones for respirable dust

Lidén, Göran. January 1996 (has links)
Thesis (doctoral)--Lund University, 1996. / Added t.p. with thesis statement inserted.
116

A history of the dust bowl /

Floyd, Fred. January 1950 (has links)
Thesis (Ph. D.)--University of Oklahoma, 1950. / Includes bibliographical references (leaves 273-311).
117

The Pluvial Lake Palomas-Samalayuca Dune systems

Domínguez Acosta, Miguel, January 2009 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
118

Far-infrared polarization by absorption in the molecular cloud sagittarius B2 /

Dowell, Charles Darren. January 1997 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics, June 1997. / Includes bibliographical references. Also available on the Internet.
119

Characterization and source apportionment of PM2.5 in the Southeastern United States

Lee, Sangil. January 2006 (has links)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007. / Wang, Yuhang, Committee Member ; Chang, Michael, Committee Member ; Bergin, Michael, Committee Member ; Mulholland, James, Committee Member ; Russell, Armistead, Committee Chair.
120

Air-quality modeling and source-apportionment of fine particulate matter implications and applications in time-series health studies /

Marmur, Amit. January 2006 (has links)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007. / Dr. Michael E. Chang, Committee Member ; Dr. Michael H. Bergin, Committee Member ; Dr. Paige E. Tolbert, Committee Member ; Dr. James A. Mulholland, Committee Member ; Dr. Armistead G. Russell, Committee Chair.

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