Organoclays modelling the Athabasca oil sands were prepared in heptane and toluene showing indole loading occurring exclusively on the external surface of the clay, via a multilayer adsorption mechanism. Solvent adsorption was minimal. Vermicular microstructures, similar to natural kaolinite were formed. Isotherms were constructed and fitted to the BET equation, giving monolayer quantities (9.28mg) that matched well to the theoretical amount calculated from surface area measurements (8.87mg). Dispersing the organoclays in isopropanol and in toluene left a monolayer equivalent. Using cellulose as a competitive desorption agent in asphaltene based organoclay dispersions achieved complete disaggregation of the dispersed organoclay stacks.13 C CP - MAS NMR, showed up to a 25% increase in desorption for aliphatic and up to 40% increase in desorption for aromatic functionalities of the loaded organic matter. Investigation of other saccharides and modified celluloses as competitive agents is recommended for future work.

Two types of protein isolates were prepared from de-hulled yellow mustard flour by aqueous extraction, membrane processing and acid precipitation of proteins at the isoelectric point (IEP 5.5). Their electrophoretic, main functional properties and protein composition were determined. The precipitated and acid soluble protein isolates had 83.0 and 96.0% protein content on a moisture and oil free basis, respectively. The acid soluble protein isolate had comparable functional properties to those of commercially available soybean and other protein isolates. The precipitated protein isolate exhibited less desirable functionality than the soluble isolate, due to its high lipid content (~25%); however, it was still comparable to soybean isolates. Storage temperature had limited effect on lipid oxidation, and hence the stability of the precipitated protein isolate at 25-45ºC. Taste and texture of wieners and bologna prepared with 1-2% of this isolate as binder were comparable to those prepared with soy protein isolates.

Two types of protein isolates were prepared from de-hulled yellow mustard flour by aqueous extraction, membrane processing and acid precipitation of proteins at the isoelectric point (IEP 5.5). Their electrophoretic, main functional properties and protein composition were determined. The precipitated and acid soluble protein isolates had 83.0 and 96.0% protein content on a moisture and oil free basis, respectively. The acid soluble protein isolate had comparable functional properties to those of commercially available soybean and other protein isolates. The precipitated protein isolate exhibited less desirable functionality than the soluble isolate, due to its high lipid content (~25%); however, it was still comparable to soybean isolates. Storage temperature had limited effect on lipid oxidation, and hence the stability of the precipitated protein isolate at 25-45ºC. Taste and texture of wieners and bologna prepared with 1-2% of this isolate as binder were comparable to those prepared with soy protein isolates.

Bentonite is a smectite type clay mineral and swells in water. In this thesis, the effect of acetone, methyl-ethyl ketone, n-hexane on the properties of bentonite was determined by thermal analysis and water absorption tests. The tests indicated no significant change with treating bentonite with organic liquids. Because of the swelling property, only small amount of bentonite can be suspended in water. This may limit certain applications of bentonite. In this thesis, feasibility of suspending large quantities of bentonite in a non-aqueous media was studied. The concentrations for a pumpable high solid bentonite slurry were determined. As aqueous slurry showed pumpable properties up to 30-35 pounds/barrel, this concentration was as high as 125-150 pounds/barrel for acetone, 175-200 pounds/barrel for methyl-ethyl ketone and 325-350 pounds/barrel for n-hexane. Bentonite deposite has a complicated composition, containing free silica minerals, such as quartz, cristobalite, and opal / silicate minerals, such as feldspar, mica, and zeolite / carbonates or sulfates of alkaline earth metals, such as calcite, dolomite, and gypsum / and, in addition, iron compounds and humus. As mined it is primarily broken and dried and then pulverized by means of an attrition grinding machine. In this study dispersion of raw bentonite by high shear blending and shaking forces in the presence of acetone, methyl-ethyl ketone and n-hexane and eliminating the non-clay impurities by screening were studied. Many attempts have been made to provide a bentonite composition retaining the full swelling properties of the bentonite by the addition of non-aqueous liquids for obtaining a flexible waterproofing sheet. In this research the possible method for deposition of bentonite in a sponge by saturating the sponge with bentonite using organic liquids was investigated.

No description available.

Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Yulin Deng; Committee Member: Howard (Jeff) L. Empie; Committee Member: J. Carson Meredith; Committee Member: Jeffery S. Hsieh; Committee Member: Timothy Patterson.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 245-274). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--Brandeis University, 2010. / "UMI:3390521." MICROFILM COPY ALSO AVAILABLE IN THE UNIVERSITY ARCHIVES. Includes bibliographical references.

Undoubtedly, water is the most abundant and important molecular liquid and is likely the most necessary for life on Earth. The pursuit of understanding water's properties and behaviors has placed it in a unique scientific and even mythical position throughout human history. It is no surprise that much scientific research today centers around this molecule and its interactions with others. The interfacial region between liquid water solutions and other phases is still poorly understood, and only recently have experiments developed to where we can probe this unique environment. Water surfaces exist throughout the Earth's atmosphere and oceans but also make up many of the microscopic interfaces necessary for metabolic processes within living cells. Yet, the influence of water surfaces on the chemistry that drives life and terrestrial processes is still largely unknown, and many research efforts today are attempting to gain insight to this critically important frontier. This dissertation documents several unique computational studies aimed to further our understanding of the complex interactions within a water system and between water and simple, common solutes. Reported herein are the results of molecular dynamics (MD) simulations and computational analysis of interfacial aqueous systems of small hydrated acids, ionic aqueous salt solutions interfaced with a liquid oil, and gas molecules adsorbing onto water surfaces. The composition of the systems chosen for the studies reported in this dissertation reflect environmentally relevant interfaces and also complement recent experimental efforts by the Richmond laboratory. Classical and quantum ab initio MD techniques were used for simulation of the molecular systems and the subsequent analyses provided new information regarding molecular interactions, geometries, orientations, and surface behaviors of water and hydrated interfacial solute molecules. This dissertation includes both previously published and unpublished co-authored material.

Made available in DSpace on 2014-06-11T19:31:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-14Bitstream added on 2014-06-13T20:41:24Z : No. of bitstreams: 1 barbosa_vt_dr_jabo.pdf: 445036 bytes, checksum: 7be58e66156743e0a9907a1b3018df87 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A leishmaniose ocular canina envolve um complexo de alterações decorrentes da atuação do agente nos diversos tecidos oculares. Valendo-se de cães com sorologia positiva para a doença, portadores (G1) ou não (G2) de alterações oftálmicas, com este estudo avaliou-se: o exame parasitológico de esfregaço a partir de swab conjuntival, a presença do parasito, pela PCR, em fragmento conjuntival e no humor aquoso (HA) e as concentrações protéicas, pela eletroforese, no HA. O parasitológico de esfregaço a partir do swab conjuntival foi positivo em 60% e 38,1% dos animais do G1 e do G2, respectivamente, com a oddsratio de 2,438 para positividade em tal parâmetro nos cães do G1, comparativamente aos do G2. A positividade na PCR de fragmento conjuntival foi maior no G1 (p < 0,005), com oddsratio igual a 17,31 quando comparados G1 e G2. O parasito não foi detectado no HA de qualquer dos grupos. Houve correlação fracopositiva entre as concentrações de IgG e de albumina séricas e do HA. Diferenças significativas foram encontradas entre os grupos, quando comparadas as proteínas totais, IgG, e proteína de peso molecular 33 kDa no HA. A haptoglobina foi detectada apenas no HA dos cães do G1. Os dados apontam para uma tendência dos cães com sinais oftálmicos serem positivos no parasitológico de esfregaço a partir do swab conjuntival e na PCR de conjuntiva, podendo, o método ser útil no diagnóstico parasitológico da leishmaniose visceral canina. Proteínas de fase aguda merecem mais avaliações quanto ao seu valor diagnóstico para esta enfermidade / Canine ocular leishmaniasis involves several ophthalmic alterations owing to the action of the parasite in numerous ocular tissues. Therefore, dogs serologically positive for leishmaniasis either presenting (G1) or not (G2) ocular alterations were enrolled in this study to evaluate the conjunctival cytology as a method for the diagnosis of this disease, the detection of the parasite in conjunctival tissue samples and in the aqueous humor using PCR, as well as the serum and aqueous humor protein concentrations determined by electrophoresis. The parasitological evaluation of the swabs disclosed 60% and 38.1% of positivity in dogs of groups 1 and 2, respectively, with a calculated oddsratio of 2.438 for a single animal testing positive in this procedure when ocular changes existed. The documented PCR results were more expressive in G1 dogs (P<0,005), with an oddsratio of 17,81 for the animals of this group testing positive using this method as compared to G2. The parasite was not found in the aqueous humor of either group. A weak positive correlation was calculated between the serum and aqueous humor IgG and albumin concentrations, and significant differences were found to exist between groups regarding total protein, IgG, and 33 kDa protein measured in the aqueous humor. Also, haptoglobin was detected only in the aqueous humor of G1 dogs. Our data suggest a tendency of dogs with ocular signs testing positive on the conjunctival swab exams and PCR, being these methods useful in the diagnosis of canine leishmaniasis. However, acute phase proteins require a more detailed evaluation concerning its diagnostic value for this disease