This work explores the usefulness of fish bile analysis in combination with biomarkers for identifying and evaluating new environmental contaminants in the aquatic environment. It illustrates how bile analysis can be used together with biomarkers to assess the causes of estrogenic effects, to identify chemicals in the aquatic environment that are taken up by fish, and to monitor environmental exposure. In a first application, fish exposed to sewage treatment plant effluent were studied. Elevated levels of vitellogenin in the exposed fish demonstrated that estrogenic effects occurred. Several estrogen disrupting substances were identified in the fish bile, and analysis of water samples confirmed that these substances were present in the effluent. The synthetic estrogen 17a-ethinylestradiol, which is known to be present in sewage treatment plant effluent, was shown for the first time to be taken up by fish. Considering the reported potencies of the detected substances, it was concluded that 17a-ethinylestradiol was the major contributor to the estrogenic effects. Chemical analysis of bile was used to identify rubber additives that were released from tires immersed in water. The bile of rainbow trout held in the water contained high levels of metabolites of PAHs and aromatic nitrogen compounds. Several biomarkers were also measured in the exposed fish, and EROD induction and oxidative stress were observed. Based on the bile analysis observations together with knowledge of toxicological mechanisms, it was postulated that the EROD induction was due to the PAHs, while aromatic nitrogen compounds caused the oxidative stress. Resin acids in fish bile proved to be a good indicator of exposure in a chronic long-term study of rainbow trout exposed to effluent from a total chlorine free (TCF) pulp mill. Elevated levels of GST (gluthatione-S-transferase) and GR (gluthatione reductase) activity, and the presence of DNA adducts after a two month recovery period, indicated that compounds in the pulp mill effluents have persistent effects. In addition to characterising the exposure of the fish to the effluent, the analysis of the resin acids in the bile provided evidence of accidents in the pulp mill that the existing process monitoring system had not detected. Resin acids in bile were also found to be a valuable indicator of exposure to pulp mill effluents for eelpout living in the Baltic Sea. A correlation between resin acid levels in bile and skewed sex ratios provided an important link in the chain of evidence that substances in the pulp mill effluents cause male bias of the eelpout embryos. A particularly good example of the potential of bile analysis was the identification of a previously unknown environmental contaminant. A large peak was observed in the bile extracts of fish that had been exposed to sewage treatment plant effluent. This peak was identified as triclosan, which demonstrated its presence in sewage treatment plant effluent. Other work went on to show that it is a common contaminant of the aquatic environment. The ability of fish to concentrate contaminant metabolites in bile to levels very much higher than in the environment, and the comparatively low levels of analytic interferences, make bile a particularly attractive matrix to search for new, unknown organic pollutants

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The scope of these studies was two-fold: to evaluate high pressure homogenized slurries as a rapid means of screening wood pulps for their Cu, Mn and Fe content and to evaluate the high pressure homogenization in combination with chelating agents or enzymatic digestion for the liberation/extraction of metal ions from this matrix. / Cu, Mn and Fe were determined successfully in pulp samples using high-pressure homogenization prior to slurry introduction-GF-AAS. The analysis time of the method from sample acquisition to determination was of the order of a few minutes per sample. / Different cellulose swelling/dissolution agents were evaluated for the generation of quasi-stable pulp suspensions, rich in cellulose. High-pressure homogenization alone or in combination with chelating agents or enzymatic digestion was also investigated as a means of quantitatively releasing these metal ions into the liquid phases. / A new model of homogenizer equipped with ceramic homogenizing valve with a few modifications was evaluated in terms of metal contamination levels within the final sample dispersion. (Abstract shortened by UMI.)

The purpose of this research work was to develop novel continuous bio-composite fibres with a combination of wood pulp or lignin and synthetic polymers, using continuous electrospinning and extrusion processes. The electrospun composite fibres have potential application in filtration, wound dressing, non-woven fabrics and support of thin polymeric separation membranes. Lignin fibres could be used for the development of carbon fibres. Two types of polyethylene oxide electronspun composite fibres (300-600 nm in diameter) were formulated using treated and untreated wood fibre. The optimum polymer solution concentration (7 wt.%) and addition of 5 wt.% wood pulp were found to produce uniform composite fibres. Superior dispersion and orientation were obtained with acetylated wood pulp as compared to untreated fibres. Similarly, wood pulp and nylon 6,6 based bio-composite fibres were generated successfully by electrospinning process. In this study solution concentration was found to be a critical parameter in regulating the diameter of fibres. Bio-composite fibres were developed from wood pulp and polypropylene (PP) by an extrusion process and subsequently characterized by various techniques. Tensile properties of composite fibres were improved by addition of maleated polypropylene (MAPP) and wood pulp. Fourier transform infrared spectroscopy provided the nature of chemical interaction between wood pulp reinforcement and PP matrix. Scanning electron microscopy results revealed that MAPP treatment was effective in increasing reinforcing fibre-matrix compatibility. X-ray computed tomography showed that the fibre becomes more aligned along the length axis possibly due to compression and die geometry of the extruder. Finally, blended lignin fibres (hardwood lignin/polyethylene oxide) were successfully developed by an extrusion process. Softening temperature and glass transition temperature of lignin were measured by differential scanning calorimetry which was helpful in selecting an optimal temperature profile for the extrusion process. Rheological studies provided information about the viscosity of hardwood lignin which was useful in producing lignin fibres.

The purpose of this research work was to develop novel continuous bio-composite fibres with a combination of wood pulp or lignin and synthetic polymers, using continuous electrospinning and extrusion processes. The electrospun composite fibres have potential application in filtration, wound dressing, non-woven fabrics and support of thin polymeric separation membranes. Lignin fibres could be used for the development of carbon fibres. Two types of polyethylene oxide electronspun composite fibres (300-600 nm in diameter) were formulated using treated and untreated wood fibre. The optimum polymer solution concentration (7 wt.%) and addition of 5 wt.% wood pulp were found to produce uniform composite fibres. Superior dispersion and orientation were obtained with acetylated wood pulp as compared to untreated fibres. Similarly, wood pulp and nylon 6,6 based bio-composite fibres were generated successfully by electrospinning process. In this study solution concentration was found to be a critical parameter in regulating the diameter of fibres. Bio-composite fibres were developed from wood pulp and polypropylene (PP) by an extrusion process and subsequently characterized by various techniques. Tensile properties of composite fibres were improved by addition of maleated polypropylene (MAPP) and wood pulp. Fourier transform infrared spectroscopy provided the nature of chemical interaction between wood pulp reinforcement and PP matrix. Scanning electron microscopy results revealed that MAPP treatment was effective in increasing reinforcing fibre-matrix compatibility. X-ray computed tomography showed that the fibre becomes more aligned along the length axis possibly due to compression and die geometry of the extruder. Finally, blended lignin fibres (hardwood lignin/polyethylene oxide) were successfully developed by an extrusion process. Softening temperature and glass transition temperature of lignin were measured by differential scanning calorimetry which was helpful in selecting an optimal temperature profile for the extrusion process. Rheological studies provided information about the viscosity of hardwood lignin which was useful in producing lignin fibres.

Refiners are used in the pulp and paper industry to separate wood chips into individual fibres and to develop the morphology of fibres to be suitable for the type and grade of paper to be produced. Within a refiner are discs, at least one of which rotates at high speed and all of which are lined with radial patterns of bars on their opposing surfaces. As the chips and fibres are accelerated through the refiner, compressive and shear forces are applied to them by the bars as the opposed discs cross each other. Experiments have shown that the contact mechanics of bar-crossings are a significant factor in the development of fibre properties. To investigate the contact mechanics in operating refiners, a prototype piezoelectric-based sensor was developed to measure the forces applied by the bars. This work re-designs the prototype sensor to function at the mill-scale, and validates the design in two trials. Performance during these trials is presented along with an in-depth analysis of the recorded data. Arrays of force sensors were installed in two single-disc refiners: a pilot-scale machine operating as a primary stage, and a mill-scale machine operating as a rejects stage. In the rejects refiner, mean forces were highest at the periphery of the refining zone, while in the primary stage, mean forces were higher at the sensor closest to the refiner axis. Higher coefficients of friction were measured in the primary stage refiner, which also showed less active bar-crossings. Distributions of peak force values were generated for a range of standard operating conditions. Primary stage refining showed near decreasing exponential distributions, while rejects refining showed skewed normal distributions. These results indicate a fundamental difference in the behavior of these refiners, which is explained in terms of the processing stage of the wood fibre and scale of the refiner. Past laboratory experiments in a single-bar refiner have shown that pulp consistency can greatly affect the contact mechanics of bar-crossing impacts. The effect was observed as a positive correlation between the coefficient of friction and the mass fraction of fibre in the stock, known as the consistency. In the present work, a similar correlation was found in the primary stage refiner, but only in the sensor closest to the refiner axis. No significant changes in the coefficient of friction were observed in the rejects refiner; however, only a small range of consistencies was tested. These initial findings suggest relationships found in past laboratory tests may translate to larger-scale equipment. The clashing of plates during refining accelerates bar wear, and delays production. An investigation of the ability of the sensor to predict plate clash was conducted. The force sensors consistently provided advanced warning of a clash event, many seconds before the accelerometer-based plate protection system currently in use by the mill. A sensitivity study showed that the new system was able to outperform the accelerometer system over a range of detection settings, and that the accelerometer could not be tuned to match the performance of the new system.

A piezo-ceramic sensor was developed to measure normal and tangential shear forces applied to a bar at one location in the refining zone of a Sunds Defibrator Conflo® JC-00 refiner. Testing was completed at the Pulp and Paper Research Institute of Canada in Vancouver. BC using CTMP pulp with a stock consistency of 3.15%. Distributions have been determined for peak normal and shear forces. peak coefficient of friction. shear work. and shear lead. These distributions were analysed to assess possible correlations with specific edge load. Force magnitudes were found to increase with an increase in specific edge load. The peak coefficient of friction was calculated that ranged from 0.13 to 0.16. Both the normal and shear force magnitudes varied by as much as a factor of 3, due to rotor out-of-tram of only 0.06 mm. These distributions could provide greater insight to the mechanisms responsible for fibre development in papermaking and thus "In Process" control of various refiner conditions.

A method for the separation and detection of standard resin acids (RAs), commonly found in pulp mill effluent and known to bioaccumulate in fish bile, was optimized using cyclodextrin modified electrokinetic capillary electrophoresis (CD-EKC) with ultra violet (UV) and laser induced fluorescence (LIF) detection. Optimal separation conditions were found with RA standards using UV detection at 214 nm, with a 72 mM sodium borate buffer pH 9.25, containing 35 mM beta-cyclodextrin sulfobutyl ether (SPCD), 15 mM of methyl-beta-cyclodextrin (MECD) and a 37 cm capillary with an internal diameter of 50pm. This resulted in a 12-min separation and the identification of 9 peaks, with a LOD of 10 ppm. To enable increased sensitivity, RAs were derivatized using the fluorescent label 4-BrMMc. A method for extracting resin acids from spiked fish bile and pulp mill effluent was developed, the extracted samples were derivatized, separated and identified using CD-EKC with LIF detection. The method of extraction and derivatization using CD-EKC was applied to biological samples of contaminated effluent and fish bile. (Abstract shortened by UMI.)