Theses and Dissertations from UMD
Permanent URI for this communityhttp://hdl.handle.net/1903/2
New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a give thesis/dissertation in DRUM
More information is available at Theses and Dissertations at University of Maryland Libraries.
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Item Characterizing the effect of atomic layer deposited coatings for the prevention of glass alteration in museum collections(2019) Hiebert, Miriam; Phaneuf, Raymond J; Material Science and Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Glass alteration in museum collections poses a serious problem for museum conservators and collections managers. There are currently few options available to slow or stop the progression of glass alteration. This thesis work has focused on assessing the potential use of atomic layer deposited (ALD) amorphous metal oxide coatings on glass as a potential solution to this problem. A modified ASTM accelerated aging method was used to age the glass samples within a time frame that could be reasonably studied, and the spatially-averaged alteration responses of the glass types chosen for this thesis were determined. The effect of applied ALD coatings on the alteration experienced by glass samples that had been subjected to accelerated aging was assessed. It was found that while TiO2 ALD films did not have a significant effect on the degree of alteration experienced, Al2O3 ALD coatings resulted in a significant decrease in the alteration response measured. The success of these coatings was limited, however, by the presence of coating defects, which expand significantly on the surface of the glass samples as a result of the accelerated aging method used. These defects stem from both the formation of pinholes in the coating during the ALD process, and cracking or buckling of the coatings due to mismatches in the coefficients of thermal expansion between the glass and the coating. Methods of mitigation for the formation of these defects and resulting coating loss were investigated. In addition to the efficacy of the ALD coatings, the appropriateness of this method for the treatment of museum objects was assessed. This included investigations of the impact on the appearance of the object imparted by the coatings. Al2O3 ALD coatings were found to have a minimal effect on the perceived color of the glass samples. In addition, the reversibility of the treatment was examined, and it was found that Al2O3 ALD are able to be removed quickly and safely from glass sample surfaces using mild alkali etchant solutions.Item A DEMONSTRATION OF GLASS BONDING USING PATTERNED NANOCOMPOSITE THERMITES DEPOSITED FROM FLUID(2015) Rodriguez, Juan Carlos; Zachariah, Michael; Mechanical Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Ceramics and other nonmetals are widely used in industrial and research applications. Although these materials provide many advantages, they often pose unique challenges during bonding. This work aims to expand on current processes, which have much narrower applications, to find a more universal method for nonmetal bonding. We utilize inks comprised of aluminum-based nanoenergetics (a heat source) and tin (a bonding agent). Requirements for successful bonding are explored and four key criteria are established. Through statistical simulation and thermochemical equilibrium calculations, we conclude that the presence of a diluent in large percentages negatively impacts reaction kinetics. Conversely, we show small percentages of added tin enhance gas generation and drive faster reaction rates. The bulk bonding material, thermite plus tin, forms a continuous structure during reaction, adhering well to the substrate surface. In some cases, these bonds failed above 1200 kPa.Item "A New Unity!" The Art and Pedagogy of Josef Albers(2004-08-10) Adler, Esther D; Mansbach, Steven A.; Art History and Archaeology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Josef Albers had an extensive and prolific career, both as an artist and a teacher. He was a crucial member of the faculties of the Bauhaus, Black Mountain College in North Carolina, and Yale University, producing a varied and ground-breaking body of his own work simultaneously. Albers's pedagogical philosophies were remarkably consistent throughout his teaching career, and all of his artwork reflects these philosophies to some degree. However, the artist's early engraved glass works, created while at the Bauhaus, and his later, architecturally-based sculptures were by far the most successful in communicating his message of the orderly, reasoned world he hoped transform through his art. Josef Albers was intent on challenging his viewer's "way of seeing," and he was able to accomplish this through his works with underlying architectural connections. These works allowed him to control the way they were perceived, and, by extension, the world seen figuratively through them.