Engineering Commons^™

Acquisition Of Laser Scanning Confocal Microscope For Biological And Materials Research, Stephen M. Shaler, Seth Shaler, Susan Brawley, Carol H. Kim, Paul J. Millard

University of Maine Office of Research Administration: Grant Reports

Biological and Materials research at the University of Maine will be strongly impacted by the acquisition of a Laser Scanning Electron Microscope as a result of this NSF-MRI award. The Leica confocal unit, along with an upright and inverted microscope and digital camera will form a multi-user facility for campus researchers working with a range of biological and materials problems. Initially, 13 faculty members from 8 academic departments have projects planned for the instrument. The microscope will be the first of its kind on the University of Maine campus.

A wide range of research problems will be attacked through use …

Mechanisms Of Print Gloss Development With Controlled Coating Structure, Sung Jai Jeon

Electronic Theses and Dissertations

Paper gloss and print gloss have long been the subject of research because of their strong influence on end-use performance such as image clarity, contrast, and resolution. This work focuses on the significance of the structural factors of porous coatings on print gloss development in a systematic way to elucidate the governing mechanisms. The coating roughness, porosity, and pore size were the three experimental variables. Generation of well defined model coating structures was a challenge and required the appropriate combinations of pigment, binder, and calendering conditions. Calendering techniques with rough substrates (polyester films) were found to produce various rough surfaces …

Platinum/Silica Thin Films By Chemical Vapor Deposition, Tyler Philip Martin

Electronic Theses and Dissertations

Composite thin films consisting of platinum and silica (SiO)₂ have been fabricated by chemical vapor deposition (CVD). These films were studied for possible future use in enhancing the selectivity of sensors for the chemical warfare agent sarin. Chemical vapor deposition is a thin film growth technique in which precursor molecules are carried into a reactor and decomposed, often at high temperature, to produce a thin solid film. A new cold wall CVD reactor was built for this work. The platinum precursor used in this work was platinum acetylacetonate [Pt(acac)₂] and the silica precursor was tetraethoxysilane (TEOS). It …

Application Of Raman Techniques For Paper Coatings, Shivashanker Bitla

Electronic Theses and Dissertations

Paper coatings are mixtures of pigments, binders and other additives used to improve the optical and printing properties of paper. During application, particle migration may occur resulting in a non-uniform distribution of pigments and binders. This may influence product quality. Raman spectroscopy is a potential tool to characterize coatings in terms of pigment/binder and pigment/pigment distribution. However, there is little work reported on this topic. Various coatings were applied to model substrates, dried and analyzed with Raman spectroscopy. CaC0₃ pigment and Styrene Butadiene latex binders are easy to detect and monitor in paper coatings when kaolin clays are not …

Development And Application Of The Zero Length Column (Zlc) Technique For Measuring Adsorption Equilibria, Federico Brandani

Electronic Theses and Dissertations

This thesis reports the results of an experimental study aimed at developing the "zero length column" (ZLC) method as a useful technique for measuring adsorption equilibria. In a ZLC experiment a small sample of adsorbent is pre-equilibrated with the sorbate, at a known partial pressure, in a He carrier. Information concerning the sorption kinetics and equilibria can be obtained fkom the desorption curve when the flow is switched to a pure He purge under carefully controlled conditions. This technique has been widely used to measure intraparticle diffusivities but, when operated at sufficiently low flow rate, it provides a simple and …

Pulp Pretreatments For Improved Selectivity And Extended Oxygen Delignification, Zheng Dang

Electronic Theses and Dissertations

Oxygen delignification has developed steadily since it was introduced commercially in 1970 in South Africa and virtually all new fiber lines incorporate an oxygen delignification system following the digester prior to the bleach plant. Currently, the degradation of cellulose and consequently the loss of pulp strength limit the drop in kappa number that can be obtained using an oxygen process. Pulp selectivity, given by the selectivity coefficient (α), relates the reduction in the molecular weight of cellulose to the reduction in the ligin content of the pulp when measured by the kappa number. An evaluation of selectivity of deligification data …

Stabilization Of Rutile-Related Thin Film On Tio2 Substrates, Youngnam Cho

Electronic Theses and Dissertations

Conducting metal oxide thin films are of broad interest because they have a wide variety of magnetic and electronic properties. Materials exist that range from superconducting to insulating, are ferromagnetic and are ferroelectric. These properties make thin conducting oxide films attractive for many industrial applications. A class of metal oxides exists that adapt the rutile crystal structure; the structure of the mineral rutile, TiO₂. These metal oxides have the general formula MO₂ where M is a metal cation of valence +4. Metal oxides crystallizing in the rutile structure also display a wide variety of physical properties. The …

Effect Of Kraft Pulping On Oxygen Delignification, Haixuan Zou

Electronic Theses and Dissertations

The objective of the study reported here was to investigate experimentally the effect of the major Kraft pulping variables on the response of brownstock pulps to medium consistency oxygen delignification. Kraft pulping was performed on mixed Northeastern hardwood chips in a laboratory rocking digester. Kraft pulps of kappa number 16 and 20 mL KMnO₄ were produced by pulping under a variety of conditions. The effective alkali (EA) charged to the digester was varied over the range of 12 to 21% while the sodium sulfide content of the pulping liquor was varied between 0 to 30% sulfidity. Cooking temperatures of …