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Optical diagnostics in diesel sprays at elevated ambient pressuresHamidi, A. A. January 1986 (has links)
No description available.
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Application of Materials Characterization, Efficacy Testing, and Modelling Methods on Copper Cold Spray Coatings for Optimized Antimicrobial PropertiesSundberg, Kristin L 18 April 2019 (has links)
The Copper Development Association (CDA) has identified over 450 copper alloys registered with the U.S. Environmental Protection Agency (EPA) as antimicrobial. With growing antibiotic resistance, there is a need for copper coatings with increased antimicrobial capability. Cold spray is a high velocity, high deposition rate process that forms dense coatings with little to no oxides or inclusions. It is possible that this process contributes to the increased antimicrobial capability of copper cold spray coatings as compared to other additive processes. The focus of this effort is to understand the effects of powder production and cold spray process parameters on copper cold spray coatings in order to optimize antimicrobial properties. Specifically, this work looks at the differences in conventional and nanomaterial copper cold spray coatings. Materials characterization and test methods show differences in adhesion, microstructure, corrosion, mechanical properties, and surface topography. Materials data is compared against Abaqus FEA software model outputs, and antimicrobial efficacy test data, based on the EPA approved procedure, is used to support materials observations and modelling outputs.
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Impact of glyphosate drift on non-target field margin invertebratesHaughton, Alison Julie January 2000 (has links)
Grassy arable field margins provide important permanent habitats for arthropods in agroecosystems and due to their proximity to high input areas, are exposed to pesticide drift. The aims of this thesis are to determine the likely effects of glyphosate drift in arable field margins by examining patterns of a medium quality spray drift intercepted by plant species in buffer strips and the effects of glyphosate on non-target field margin arthropods. Levels of mediumquality spray drift, analogous to herbicide drift, intercepted by field margin plant species in field boundaries were significantly reduced by inclusions of 2m and 6m wide buffer strips. Levels of spray drift interception varied between plant species and were related to plant height and leaf area. Dose-response testing of glyphosate against field margin plant species was done to establish inherent susceptibilities to the herbicide. Many species appeared to be unaffected by high levels of glyphosate (1800g ha<sup>-1</sup>), while others had relatively high ED<sub>50</sub>s that were unlikely to be exceeded by UK recommended rates of glyphosate. It was noted that lack of exposure to interspecific competition may have enhanced the plant species tolerance to high levels of glyphosate. Different rates of glyphosate were screened against the non-target arthropods Lepthyphantes tenuis (Araneae) and Leptopterna dolabrata (Heteroptera) to assess toxicity. Glyphosate was found to be non-toxic, however, applications of glyphosate to food plants increased mortality in L. dolahrata. In a field experiment, glyphosate applications of more than 360g ha<sup>-1</sup> to a grassy arable field margin reduced Araneae, Heteroptera and Carabidae abundance. Community analyses (DCA) indicated that communities in the field margins exposed to more than 360g ha<sup>-1</sup> glyphosate were distinct from unsprayed field margins. It is predicted that drift of field applied glyphosate at rates greater than 1440g ha<sup>-1</sup> would reduce phytophagous Heteroptera and Gonalium rubens (Araneae) abundance.
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Measurements in swirl-stabilised spray flames at blow-offYuan, Ruoyang January 2015 (has links)
No description available.
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THE EFFECTS OF FLAME TEMPERATURE, PARTICLE SIZE AND EUROPIUM DOPING CONCENTRATION ON THE PROPERTIES OF Y2O3:EU PARTICLES FORMED IN A FLAME AEROSOL PROCESSYim, Hoon 2009 May 1900 (has links)
Y2O3:Eu particles are phosphors that have found wide applications. Flamesynthesized
Y2O3:Eu particles may have either the cubic or the monoclinic structure. The
effects of particle size and Eu doping concentration on crystal structure and the surface
elemental composition of the flame-synthesized Y2O3:Eu particles had not been
previously reported.
In this study, a flame aerosol process was used to generate polydisperse Y2O3:Eu
particle. H2 was used as the fuel gas, with either air or O2 gas as the oxidizer. The
precursor was aqueous solutions of the metal nitrates, atomized using a 1.7-MHz
ultrasonic atomizer. The product particles were analyzed by transmission electron
microscopy (TEM), X-ray diffractometer (XRD), Selected area electron diffraction
(SAED), X-ray photoelectron spectroscopy (XPS), fluorescence spectrophotometer, and
inductively coupled plasma mass spectrometer (ICP-MS).
The Y2O3:Eu particles generated in H2/O2 flames were spherical and fully dense,
with diameters in the range of 10~3000 nm. In particle samples with lower Eu doping
concentrations, a critical particle diameter was found, whose value increased with increasing Eu doping concentration. Particles well below the critical diameter had the
monoclinic structure; those well above the critical diameter had the cubic structure. At
sufficiently high Eu doping concentrations, all Y2O3:Eu generated in H2/O2 flames had
the monoclinic structure. On the other hand, all particles generated in the H2/air flames
had the cubic structure. For the Y2O3:Eu particles generated in H2/O2 flames, XPS
results showed that the surface Eu concentration was several times higher than the
doping concentration. For Y2O3:Eu particles generated in H2/air flames, the surface Eu
concentration was equal to the doping concentration. For both types of particles, the
photoluminescence intensity reached a maximum corresponding to a surface Eu
concentration 40~50%. The photoluminescence intensity then decreased rapidly with
higher Eu doping concentration.
The effect of particle size and Eu doping concentration on crystal structure may
be explained by the interplay between surface energy and polymorphism. A mechanism
for this surface enrichment phenomenon was proposed based on the binary Eu2O3-Y2O3
phase diagram.
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Spray-dried o/w-emulsions for oral delivery of poorly soluble drugs /Hansen, Tue. January 2004 (has links)
Ph.D.
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Heat Transfer Analysis of Flame-sprayed Metal-polymer Composite StructuresTherrien, David S Unknown Date
No description available.
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Herbicide effects on a plant community and on monocultures of different densitiesHumphry, Roger William January 1999 (has links)
No description available.
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Decompressive production of micronized powders a parametric study /Wiser, William January 2007 (has links)
Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 17, 2008). Includes bibliographical references (p. 206-215).
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Painting with air /Eoff, John. January 1977 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 1977. / Typescript. Includes bibliographical references (leaves 47-48).
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