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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.
131

Habitat fragmentation and woodland amphibians consequences for distribution, genetic diversity and fitness responses to UV-B radiation /

Weyrauch, Shauna L., January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiv, 138 p. : ill. Advisor: Thomas C. Grubb, Dept. of Evolution, Ecology, and Organismal Biology. Includes bibliographical references (p. 129-138).
132

Novel III-Nitride growth by ultraviolet radiation assisted metal organic molecular beam epitaxy

Pritchett, David Chu. January 2009 (has links)
Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Doolittle, W. Alan; Committee Member: Carter, W. Brent; Committee Member: Ferguson, Ian T.; Committee Member: Frazier, A. Bruno; Committee Member: Rincon-Mora, Gabriel A.
133

A study of the effect of water-pick up of UV curable offset ink on its curing time and its end use properties /

Fatnasare, Ike S. January 1993 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaves 58-60).
134

Regeneration von extremitäten bei tritonen nach zusatz bestimmter chemikalien und ultra-violettbestrahlung ...

Doerbecker, Hans Joachim, January 1938 (has links)
Inaug.-Diss.--Rostock. / At head of title: Aus der Rostocker Chirurgischen universitätsklinik. Lebenslauf. "Literatur": p. 17.
135

Spectra of hydrogen, nitrogen and oxygen in the extreme ultraviolet

Hopfield, John Joseph, January 1900 (has links)
Thesis (Ph. D.)--University of California, 1923. / Reprint from the Physical review, s. s., vol. XX, no. 6, December, 1922, with a special thesis t.p. attached to the cover. Approval page inserted. Cover title.
136

The source and character of a flavor produced in milk by ultra-violet and solar radiation

Flake, John C., January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 71-78).
137

Ultraviolet measures of the day sky and observations of bright OBA stars for space astronomy applications

Burkhead, Martin Samuel, January 1964 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
138

Responses of two species of Caribbean shallow-water branching corals to changes in ultraviolet radiation /

Torres-Perez, Juan Luis. January 2005 (has links) (PDF)
Thesis (Ph.D.)--University of Puerto Rico, Mayaguez Campus, 2005. / Includes bibliographical references.
139

IMPACT OF ULTRAVIOLET ENERGY ON STRAWBERRY SHELF LIFE

Carpenter, Christopher E. 01 January 2009 (has links)
Ultraviolet energy has been used in the past to disinfect drinking water and fruit juice. This paper will discuss the impact of ultraviolet energy on strawberry shelf life. The ultraviolet tunnel used in the study utilizes lamps that are designed to emit specific narrow wavelength spectrum, of 253.7 nanometers. The tunnel was made of polished aluminum and reflects beams of energy within the tunnel. Ultraviolet energy can improve food safety by destroying the microorganisms, such as E coli and salmonella that cause food-borne illnesses. Ultraviolet energy can extend shelf life of produce and make it possible to keep these foods for greater periods of time while keeping the integrity of the berry intact. A review of literature was conducted to identify the pathogens that affected this study, these pathogens were: Grey Mold, Botrytis cinerea ; Dry Crown Rot Botryotinia fuckeliana ; Phomopis Leaf Blight, Phomopsis obscurans and Dendrophoma obscurans ; Rhizopus Rot (leak), Rhizopus stolonifer ; and Tan-brown rot, Discohainesia oenotherae . It was found that ultraviolet viable application range rate were 88.1mj/cm3, 140mj/cm3, 191.9mj/cm3, 243.8mj/cm3, 295.7mj/cm3 and 347.6mj/cm3 lasted longest and these rates were used in the full test run. Results indicated that a significant shelf life extension of strawberries was achieved at each of these treatment levels. The average shelf life of non-treated berries was 14.9 days whereas the average treated strawberries range from 17.25 to 20.9 days. A lowest level of treatment was reached at 15 seconds or 88mj/cm3. A statistical relationship between application rates and shelf life was determined. Using an ANOVA table at 95% confidence interval, it was determined when all samples, as individuals, were considered that the shelf life was extended by exposure to ultraviolet energy. Another ANOVA table was used for each treatment group versus the control group, all treatment groups showed a significant difference opposed to the control group. In conclusion, this study shows that applying ultraviolet energy to strawberries significantly improves shelf life. There was not a significant benefit to exposing the strawberries to added ultraviolet energy.
140

Characterisation of polar (0001) and non-polar (11-20) ultraviolet nitride semiconductors

Chang, Tse Yang January 2012 (has links)
UV and deep-UV emitters based on AlGaN/AlN heterostructures are very inefficient due to the high lattice mismatch of these films with sapphire substrates, leading to high dislocation densities. This thesis describes the characterisation of the nanostructures of a range of UV structures, including c-plane (polar) AlGaN epilayers grown on AlN template, and nonpolar GaN/AlGaN MQWs grown on a-plane GaN template. The results are based primarily on transmission electron microscopy (TEM), cathodoluminescence in the scanning electron microscope (SEM-CL), high-resolution X-ray diffraction (HRXRD) and atomic force microscopy (AFM) measurements. The structural and optical properties of various types of defect were examined in the c-plane AlGaN epilayers. Strain analysis based on in-situ wafer curvature measurements was employed to describe the strain relief mechanisms for different AlGaN compositions and to correlate the strain to each type of defect observed in the epilayers. This is followed by the investigation of AlN template growth optimisation, based on the TMA pre-dose on sapphire method to enhance the quality and the surface morphology of the template further. The initial growth conditions were shown to be critical for the final AlN film morphology. A higher TMA pre-dose has been shown to enable a better Al coverage leading to a fully coalesced AlN film at 1 μm thickness. An atomically smooth surface of the template was achieved over a large 10 x 10 μm AFM scale. Finally, the investigation of UV emitters based on nonpolar crystal orientations is presented. The SiNx interlayer was able to reduce the threading dislocation density but was also found to generate voids with longer SiNx growth time. The relationship between voids, threading dislocations, inversion domain boundaries and their associated V-defects and the variation in MQW growth rate has been discussed in detail.

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