<p> In part I of this dissertation, several cationic polyacrylamides were tested under different conditions for their ability to improve the retention of fines in papermaking. A dynamic drainage jar was used to simulate the turbulence encountered in the papermaking process. Several factors, including temperature, the amount and intensity of turbulence, the additive concentration and the presence of impurities were found to affect fines retention with polymers present. A polymer made by Nalco Chemicals proved to be superior to a commonly used polymer, Percol 292 for a standard fine paper pulp. It was thought that further retention improvements might be possible by tailoring the charge density and molecular weight of polyacylamide retention aides for the specific papermaking system they are intended for. Novel approaches to retention such as those employing combinations of an anionic polymer, a cationic polymer and zirconium oxychloride were thought to show promise as well.</p> <p> In part II of this dissertation several broad polyacrylamide molecular weight standards were prepared by inverse suspension and solution processes on pilot plant equipment at the McMaster Institute for Polymer Production Technology. They were characterized by laser light scattering and viscometry at McMaster, and externally by other methods. Although the polyacrylamides prepared compare favourably to currently available commercial standards when both are analysed by SEC, further analysis must be done to be certain of the molecular weight averages.</p> <p> A relationship is presented to provide for simpler and more accurate light scattering analysis in the future. This relationship relating Mw to the second Virial coefficient may be used to eliminate some uncertainty in the often scattered plots encountered when calculating molecular weights for polyacrylamides analysed by light scattering.</p> / Thesis / Master of Engineering (MEngr)

<p> This project was undertaken with the aim of studying the distribution of copper, manganese and zinc in brain and to gain same information on the possible presence of soluble metallo-proteins in this tissue. The distribution of copper, manganese and zinc has been determined by neutron activation analysis. Soluble metallo-proteins of these three elements have been identified by the combination of gel chromatography and neutron activation analysis. In addition, in vivo and in vitro radioisotopic labelling techniques have been used occasionally.</p> / Thesis / Doctor of Philosophy (PhD)

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This study aimed to quantify resistant starch (RS) beta-glucans (BG) and fructo-oligosaccharides (FOS) in Indian and Canadian wheat varieties and in chapaties made from these; and to assess the effects of soy flour on the levels of these components and its effects on the sensory and functional properties of the wheat-soy chapaties. Seven wheat varieties (Indian / Canadian) were milled into flour; supplemented with 0 % (control), 10 %, 20 % or 30 % defatted soy flour and made into chapaties. Flours and chapaties (freeze-dried, pulverized) were assayed for BG, FOS, RS and simple sugars (glucose / sucrose). Sensory evaluation was carried out by (9 point) hedonic rating of chapaties by 20 untrained Indian panelists. Flour water-holding capacity and water absorption indices (WAI) were determined. RS content of flours ranged from 7.1 g/100 g to 12.6 g/100g, but decreased when made into chapaties, (< 1 g/100 g), and decreased further with soy flour addition. BG content in flours ranged from 0.8 g/100 g to 1.4 g/100 g, while FOS content ranged from 1.3 g/100 g to 2.3 g/100 g. Minimal changes were observed in BG and FOS content when made into chapaties. Simple sugars were minimal in flours and chapaties. WAI of wheat flour was increased with addition of soy bean flour. Addition of up to 30 % soybean flour elevated the sensory acceptability of chapaties. While there is a decrease in RS with chapati making, the levels of BG and FOS are largely unchanged with processing. / Master of Science

In recent years two-phase catalysis has been established as a new field of catalyzed processes and has achieved industrial-scale importance in olefin hydroformylation. Two-phase reactions have a number of advantages, for example, ease of separation of catalyst and product, catalysts can be tailored to the particular problem, use of special properties and effects of water as a solvent, and low environmental impact. For higher olefins (* C6), the reaction suffers low activity due to low water solubility of higher olefins. Tricesium analog of TPPTS, m,m,m-trisulfonated triphenylphosphine, was synthesized and fully characterized. Two-phase olefin hydroformylation with Rh(acac)(CO)2 was investigated. The results indicated that both activity and selectivity (linear to branch aldehyde ratio) are similar to Rh/TPPTS system. The salt effect showed that increase the solution ionic strength will increase the selectivity and decrease the activity in the olefin hydroformylation with TPPTS. A new surface active phosphine, trisulfonated tris-m-(3henylpropyl)phenylphosphine, was synthesized and fully characterized. The results of biphasic olefin hydroformylation were consistent with aggregation of the ligand. The two phase 1-octene hydroformylation results showed that with only 3 methylene groups, there is no difference between the para and meta position of C3 group. A new chelating diphosphine, tetrasulfonated 2,2'-bis{di[p-(3 phenylpropyl)phenyl]phosphinomethyl}-1,1'-biphenyl,was prepared and fully characterized. Its application in two-phase hydroformylation of olefin showed enhanced activity and selectivity compared to the non-chelated phosphine analog. Finally, homogeneous asymmetric hydrogenation was carried out in the presence of a chiral surfactant in an attempt to affect asymmetric induction. The catalytic results showed that at a surfactant/Rh ratio of 25, the asymmetric hydrogenation of AACA-Me (a-Acetamidocinnamic Acid Methyl Ester) in methanol has no effect on asymmetric induction with the introduction of this chiral surfactant. / Master of Science

Wide literature precedence exists for polymers containing electrostatic interactions and polymers containing hydrogen bonding motifs, however the combination of electrostatic and hydrogen bonding interactions is not widely investigated in current literature. Polyelectrolytes containing hydrogen bonding groups are expected to exhibit properties of both classes of supramolecular interactions. A series of adenine- and thyminecontaining PDMAEMA and tert-butyl acrylate copolymers were synthesized to investigate the effect of incorporating hydrogen bonding groups into a polyelectrolyte. Incorporation of the styrenic nucleobases significantly affected the solubility of these copolymers on aqueous solutions and showed salt-triggerability with higher contents of these groups. Polyelectrolytes are capable of binding and condensing DNA through electrostatic interactions with the negatively charged phosphate groups of the DNA backbone; however a high degree of cytotoxicity is also often observed for these gene delivery systems. The high level of cytotoxicity is attributed to high degree of cationic character for the polyplexes formed with these systems according to the proton-sponge hypothesis. One method of reducing the overall cationic character for these systems is incorporation of non-electrostatic binding mechanisms such as hydrogen bonding. A series of nucleobase-containing PDMAEMA copolymers were utilized in order to investigate the effect of incorporation of these groups on the cell viability, binding efficiency, and transfection efficiency of PDMAEMA. / Master of Science

The objective of this study was to determine how the key features of bioreactor landfills; increased temperature, moisture and microbial activity, affect the biological stability of the landfill material. In the first part of the study the solubilization and degradation of lignin in paper exposed to these bioreactor landfill conditions are explored. The solubility of the lignin in paper was observed at different temperatures and over 27 weeks at 55°C and the anaerobic bioconversion of office paper, cardboard and Kraft lignin was observed in bench-scale reactors over 8 weeks. As the temperature rose, lignin solubility increased exponentially. With extended thermal treatment, the dissolution of lignin continues at a constant rate. This rate increases 15 times for paper and 1.5 times for cardboard in the presence of rumen inoculum compared to un-inoculated systems. At around 6 weeks the inter-monomeric linkages between the solubilized lignin molecules began breaking down, releasing monomers. In cardboard and Kraft lignin, a significant amount of the monomers mineralize to CO₂ and CH₄ during this time period. The results indicate that small, but significant rates of lignin solubilization and anaerobic lignin degradation are likely to occur in bioreactor landfills due to both higher temperature and microbial activity. In the second part of the study, field data from the Outer Loop Recycling and Disposal Facility in Louisville, Kentucky was evaluated to determine the effectiveness of an anaerobic-aerobic landfill bioreactor (AALB) vs. the control landfill that is managed as a traditional landfill. Moisture, temperature, elevation and the amount of time the MSW has spent in the landfills (age) were measured and compared to determine the factors that affect the biological stability of the landfill. The results showed that the MSW in the AALB is more biologically stable than the MSW in the control landfill, indicating that they are more degraded. Additionally, elevation or location of the MSW was the key factor in determining the extent of MSW stability within the AALB and temperature is the key factor in determining the biological stability of the MSW in the control landfill. Higher temperatures correlated with a more biologically stable waste. The cellulose to lignin ratio (C/L ratio) and biochemical methane potential (BMP) were the main biological stability parameters used. / Master of Science

No / Of particular importance in recent years has been the development of techniques for producing nanoparticles (NPs) of poorly-water soluble drugs with dimensions less than 1000 nm for which their high surface area can lead to improvements in bioavailability. Furthermore, the small size of these particles can also enable cellular uptake, particularly for positively charged systems. Therefore, an overall objective of this part of the project was to produce nanoparticles with different levels of positive surface charge using the bottom-up method.