Analytical modelling of bacterial migration and accumulation with rate-limited sorption in discrete fractures

An analytical model for bacterial accumulation in a discrete fractllre has been developed. The transport and accumlllation processes incorporate into the model include advection, dispersion, rate-limited adsorption, rate-limited desorption, irreversible adsorption, attachment, detachment, growth and first order decay botl1 in sorbed and aqueous phases. An analytical solution in Laplace space is derived and nlln1erically inverted. The model is implemented in the code BIOFRAC vvhich is written in Fortran 99. The model is derived for two phases, Phase I, where adsorption-desorption are dominant, and Phase II, where attachment-detachment are dominant. Phase I ends yvhen enollgh bacteria to fully cover the substratllm have accllillulated. The model for Phase I vvas verified by comparing to the Ogata-Banks solution and the model for Phase II was verified by comparing to a nonHomogenous version of the Ogata-Banks solution. After verification, a sensitiv"ity analysis on the inpllt parameters was performed. The sensitivity analysis was condllcted by varying one inpllt parameter vvhile all others were fixed and observing the impact on the shape of the clirve describing bacterial concentration verSllS time. Increasing fracture apertllre allovvs more transport and thus more accllffilliation, "Vvhich diminishes the dllration of Phase I. The larger the bacteria size, the faster the sllbstratum will be covered. Increasing adsorption rate, was observed to increase the dllration of Phase I. Contrary to the aSSllmption ofllniform biofilm thickness, the accllffilliation starts frOll1 the inlet, and the bacterial concentration in aqlleous phase moving towards the olitiet declines, sloyving the accumulation at the outlet. Increasing the desorption rate, redllces the dliration of Phase I, speeding IIp the accllmlilation. It was also observed that Phase II is of longer duration than Phase I. Increasing the attachment rate lengthens the accliffililation period. High rates of detachment speeds up the transport. The grovvth and decay rates have no significant effect on transport, althollgh increases the concentrations in both aqueous and sorbed phases are observed. Irreversible adsorption can stop accllillulation completely if the vallIes are high.

Sol-gel routes to supported Friedel-Crafts alkylation catalysts

Aluminosilicate catalysts containing supported ZnCl2 and metal fluoride salts have been prepared using a sol-gel based route, tested and characterized. The activities of these ZnCl2 + metal fluoride catalysts, while greater than "Clayzic" (ZnCI2 supported on montmorillonite KIO) are not as good as supported ZnCl2 only supported on aluminosilicate. Alumina supports have also been prepared via a sol-gel route using various chemical additives to generate a mesoporous structure, loaded with ZnCl2 and tested for activity. The activities for these alumina-supported catalysts are also significantly higher than that of "Clayzic", an effective Friedel-Crafts catalyst. Characterizations of these two types of catalysts were done by magic angle spinning (MAS) NMR, diffuse reflectance infrared (DRIFT) spectroscopy and additionally for the alumina nitrogen adsorption studies were done. Supported aluminum trichloride was also investigated as an alternative to the traditional use of aluminum trichloride.

The Smiles rearrangement in hydrazidic systems and related syntheses /|nG. A. Pawelchak. -- 260 St. Catharines, Ont. : [s. n.],

This research was directed towards the investigation of the Smiles rearrangement in hydrazidic systems and the synthesis of related heterocyclic compounds. The work can be conveniently divided into two main sections. Section 1 of the thesis relates to the synthesis and examination of the O+N migration of phenoxy- derivatives of hydrazidic halides. In general, hydrazidic halides were found to react with 2-nitrophenol and 4-nitrophenol to give corresponding a-nitrophenoxy- compounds. These a-nitrophenoxy- compounds were found to rearrange in warm base to give the corresponding N-benzoyl compounds via a proposed five-membered transition state. Experiments conducted in styrene revealed no radical contribution to the rearrangement. Cross-over product analysis indicated the rearrangement as intramolecular and consistent with the Smiles rearrangement. The preparation of N-a-chlorobenzylidene-N'-2-nitrophenyl- -N'-(2,4-dibromophenyl)hydrazine from N-benzoyl-N'-2-nitrophenyl- N'-(2,4-dibromophenyl)hydrazine was accomplished using phosphorus oxychloride. Examination of this hydrazidic chloride indicated a marked decrease .in reactivity as compared to the N-a-chlorobenzylidene-N'-phenylhydrazine case. Section 2 concerns itself with the preparation of heterocyclic compounds using an analogy of the five-membered transition state present in the Smiles rearrangement of a substituted benzylidene derivatives A new preparation of 2,4-phenyl1,3,4- oxadiazol-S-one using N-benzoyl-N'-phenylhydrazine and ethyl thiochloroformate is reported. Two new preparations of N-a-thiobenzoyl-N'-(2,4-dibromophenylhydrazine are reported using sodium hydrosulfide in conjunction with N-a-bromobenzylidene-N'-(2,4-dibromophenyl)hydrazine in the first, and phosphorus pentasulfide with N-benzoylN'-( 2,4-dibromophenyl)hydrazine in the second. The latter is preferred due to the formation of a sulfide co-product in the former. Two preparations of 2-phenyl-4-(2,4-dibromophenyl)-1,3,4- thiadiazol-S-one are reported using N-thiobenzoyl-N'-(2,4-dibromophenyl) hydrazine and ethyl chloroformate and ethyl thiochloroformate Two rapid and easy preparations of 2-phenyl-4-(2,4-dibromophenyl)- 1,3,4-triazol-S-one are reported using ethyl chloroformate and ethyl thiochloroformate. Sodium cyanate in conjunction with a-aminobenzylidene-N'-(2,4-dibromophenyl)hydrazine also provided 2-phenyl-4-(2,4-dibromophenyl)-1,3,4-triazol-S-one Section 2 concludes with an examination of two possible mechanistic routes to the prepared heterocycles.

Pen and sunlight sketches of scenery reached by the Grand Trunk Railway system and connections with summer routes and fares to principal points : including Niagara Falls, Thousand Islands, Rapids of the St. Lawrence, Montreal, Quebec, Parry Sound, Georgian Bay, Muskoka Lakes, Adirondacks, Lake St. John, Mackinac Island, Midland District Lakes, the White Mountains, the Suquenay River, Rangeley Lakes and the sea-shore.--

At head of title: "Great tourist route of America".

Global migration : patriarchy, propoganda and the well- being of women and children

This critical analysis explores the conflicted position of women as ''trailing spouses" and the effects on families who relocate globally under the auspices of a multinational corporation, by utilizing a discursive analysis of two contemporary films and available literature. Current portrayals of women and children in contemporary media provide emotional yet conflicting images of the perfect woman, wife, mother, child and family. The basic tenets of a North American patriarchal economic system are being televised around the world. Technological advancements have made it possible to advertise political agendas on a global television screen. Much of what we see is propaganda couched in films and advertisements that are designed to romantic~e the practice of deriving profits from the unpaid labor of woman and invisibility of children and child rearing. I intend to show that the materiality of trailing a spouse globally conflicts with these romanticized images and supports feminist literature that asserts the notion that mothers and children are oppressed and managed for the benefit of capital.

Les déterminants de la migration interrégionale au Québec: caractéristiques des régions et des migrants.

Rapport de recherche