Water is critical for food production, food security, and health. Water quality management influences freshwater sustainability, land, and energy administration. Global agriculture accounts for more than 70% of all water consumption; the fertilizer, manure, and pesticide overspills are chief sources of water pollution worldwide. On a global scale, food-related waste directly impacts local food production and water resource management. The purpose of this multiple-case study on the food and beverage (FB) industry in the State of Georgia was to identify successful strategies for improving water management efficiency. The concepts of systems thinking, adaptive resource management, and integrated water resource management provided the conceptual framework for the study. Data were collected via personal interviews with 2 global supply chain leaders in the FB industry and 1 water expert in the public water utility system in Georgia. The findings showed 10 themes: sustainability; mission-driven culture; ethical responsibility; water quality and governance; food safety and sanitation; water conservation and climatic trends; waste management; nutrition and the freeze drying method; knowledge sharing and collaboration; and water detention and retention systems. The study results are intended to contribute to social change by providing information to global supply chain leaders, policy makers, entrepreneurs, and sustainability leaders to implement sustainability beyond the environmental value; these findings will also help achieve a positive posture on resource overconsumption and waste management for efficient and complex decision making within a worldwide spectrum.

L'objectif de cette thèse était de développer et de caractériser la microstructure et les propriétés mécaniques des céramiques bio-inspirées. L'alumine inspirée par la nacre fabriquée par texturation à la glace (freeze-casting), précédemment développée dans le cadre de la thèse de F. Bouville, a été choisie comme matériau de référence. La simplification et le changement d’échelle du procédé d’élaboration des matériaux ont été étudiés. Le procédé sophistiqué de freeze-casting a été remplacé par le pressage uniaxial à cru. Les mesures de diffraction des électrons rétrodiffusés ont confirmé le bon alignement après frittage des plaquettes d'alumine utilisées pour préparation du matériau. Le cycle de frittage assisté par effet de champs a été adapté à de plus grandes quantités de poudre céramique et d'additifs organiques. La deuxième partie du projet a été consacrée à la modification de l'interphase entre les plaquettes d'alumine, afin d’améliorer les propriétés mécaniques du matériau. Diverses possibilités ont été explorées: ajout de poudre de zircone, dépôt de zircone sur les plaquettes par réaction sol-gel ou substitution de la phase vitreuse par du graphène. Tous les matériaux obtenus ont été caractérisés par flexion quatre points sur des barrettes entaillées. La troisième partie de cette étude a porté sur le développement de composites multicouches métal/céramique, par frittage simultané d'alumine et de titane. L'épaisseur et la composition de la feuille de titane ont été modifiées pour étudier leur influence sur les phénomènes de diffusion lors du frittage. Les composites ont été caractérisés par MEB, EBSD, spectroscopie à rayons X à dispersion d'énergie et tomographie à rayons X au synchrotron. La fabrication simplifiée des matériaux permet de préparer des échantillons de plus grandes dimensions de céramiques inspirées par la nacre, sans passer par une étape de freeze-casting. Cependant, la croissance des grains doit être limitée pour maintenir de bonnes propriétés mécaniques. La modification de l'interphase entre les plaquettes d'alumine n'a pas amélioré les propriétés mécaniques des matériaux par rapport au matériau de référence. D'autre part, le dépôt de nano-zircone sur la surface des plaquettes semble prometteur et devrait faire l'objet d'études plus poussées. Dans le cas des composites alumine/titane, les composites architecturées multiéchelles ont été fabriqués de manière assez simple. Cependant, il est crucial d'éviter la fissuration des feuilles de métal afin d’améliorer les propriétés mécaniques. / The goal of this thesis was to develop and characterize the microstructure and the mechanical properties of bioinspired ceramic composites. Nacre-like alumina fabricated by freeze-casting previously developed in Bouville thesis was chosen as a reference material. Simplifying and up-scaling material fabrication was intended. Architectural levels were added to the microstructure to further improve mechanical properties of the material. Sophisticated processing by freeze-casting was substituted by uniaxial pressing. Electron backscatter diffraction observations confirmed the good alignment of alumina platelets used to prepare the material. The field assisted sintering cycle was adapted to greater quantities of ceramic powder and organic additives. The second part of the project was dedicated to the modification of the interphase between alumina platelets. Various possibilities were explored: adding fine zirconia powder, depositing zirconia on the platelets by sol-gel reaction, or substituting the glassy phase by graphene. All obtained materials were characterized by four point bending on notched bars. The third part of this study was focused on the development of multilayered metal/ceramic composites, by simultaneous sintering of alumina and titanium. The titanium foil thickness and composition were varied. The composites were characterized by SEM, EBSD, energy dispersive X-ray spectroscopy and synchrotron X-ray tomography. Detailed microstructural and chemical characterization was performed to understand mechanisms of titanium diffusion into ceramic matrix. Simplified material fabrication allows to prepare larger samples of nacre-like ceramics. However grain growth should be limited to maintain good mechanical properties. Modification of the interphase between alumina platelets did not improve mechanical properties of the materials as compared to the reference material. On the other hand, depositing nano-zirconia on platelets surface seems promising and should be further investigated. In case of alumina/titanium composites, a multiscale architecture composites were process in a rather simple way. However, avoiding metal foil cracking is crucial to improve mechanical properties.

A multistage production system consists of a number of production stages that are interrelated, that is the output from one stage forms input to the next stage. There are constraints associated with each stage as well as constraints imposed by the overall system. Besides, there are multiple objectives that need to be satisfied, and in numerous cases, these objectives conflict with each other. What is required is an efficient technique to allocate and schedule resources so as to provide a balance between the conflicting objectives within the system constraints. This study is concerned with the problem of scheduling multistage production systems in food processing industry. The system and products have complex structure and relationships. This makes the system difficult to be solved analytically. Therefore, the problem is solved by developing a heuristic algorithm that considers most of the constraints. The output generated by the algorithm includes a production schedule which specifies the starting and completion times of the products in each stage and the machines where the products are to be processed. In addition, a summary of system performances including throughput times, resources' utilizations, and tardy products is reported. / Graduation date: 1992

Le monoxyde d'azote est exclusivement synthétisé chez les mammifères par une famille d'hémoprotéines, les NO-Synthases. Le cœur de l'activité des NO-Synthases est l'activation de l'oxygène c'est-à-dire l'activation de l'intermédiaire réactionnel FeIIO2. Cette étape est contrôlée par la réactivité intrinsèque du fer, par les transferts de proton et les transferts d'électron. Elle doit être parfaitement maîtrisée car elle contrôle le chemin catalytique emprunté et la nature du produit final. Comprendre l'étape d'activation de l'oxygène est essentiel à la compréhension du rôle biologique et/ou pathologique de la NO-Synthase de mammifère. Cette question s'étend aux NO-Synthases bactériennes pour lesquelles on ne connait ni le mécanisme moléculaire ni la fonction biologique. Ce manuscrit propose une analyse approfondie de l'étape d'activation de l'oxygène de la NO-Synthase. Dans un premier temps, nous avons étudié l'influence de l'environnement proximal sur la réactivité intrinsèque du fer et l'activation de l'oxygène. Nous avons généré des protéines mutées qui modifient les propriétés électroniques de la liaison proximale de l'hème. Ces protéines mutées ont été caractérisées par différentes spectroscopies (résonance paramagnétique électronique, Raman de résonance). Dans un second temps nous avons directement étudié le complexe FeIIO2, en présence d'analogues de substrat, grâce à des analyses de cinétique rapide en flux continu et en flux arrêté (stopped-flow). Dans un troisième temps, le rôle du cofacteur tetrahydrobioptérine dans le transfert de proton et d'électron a été étudié par une méthode de piégeage à des temps très courts : le freeze-quench. L'ensemble de nos résultats montrent que l'activation de l'oxygène est régulée par les propriétés électro-donneuses du ligand proximal et par le réseau de liaisons H distal. Nous mettons en évidence des différences dans le rôle redox du cofacteur tetrahydrobioptérine entre la NO-Synthase de mammifère et la NO-Synthase bactérienne. La difficulté majeure pour comprendre l'étape d'activation de l'oxygène de la NO-Synthase réside dans la complexité et la rapidité de la réaction catalytique. Dans ce contexte, nous avons cherché à adapter une méthodologie qui a prouvé son efficacité dans le cas des cytochromes P450 : la cryo-réduction couplée à des sauts en température.

University of Macau / Institute of Chinese Medical Sciences

The introduction of the use of Tire Pressure Control Systems (TPCS) to improve the productivity of the Canadian trucking industry is gaining momentum. The imposition of seasonal load restrictions (SLR) on the thaw-weakened secondary roads interrupts the transportation of raw materials to processing facilities For the forestry industry in particular, this has very significant impacts on productivity and costs. FPInnovations-Feric Division (Feric) has investigated the potential for TPCS-equipped trucks to travel with full, legal loading during the SLR period without accelerating road wear and tear. The TPCS monitors and adjusts the inflation pressure of the trucks’ tires while driving and allows the operator to optimize the inflations for changes in loading, travel speed, or road quality encountered in the trip. This thesis describes an investigation to determine whether TPCS can be used to mitigate traffic generated damage to secondary roads and also reduce the need to implement load restrictions. The project involves a partnership with the Ontario Ministry of Transportation Ontario (MTO), Forest Engineering Research Institute of Canada (FERIC), Ontario Ministry of Natural Resources (MNR) and the Centre for Pavement and Transportation Technology (CPATT) located at the University of Waterloo. The thesis will describe the methodology, design, and instrumentation of the two test sites which are located in Dryden, Ontario and Chapleau, Ontario. In addition, repeated Portable Falling Weight Deflectometer (PFWD) testing is being carried out at these sites and the initial results of this examination and associated impacts of the environment and traffic on the road will be presented. This study also involves looking into the reliability of using the portable FWD, offering a lower cost alternative instead of the trailer mounted FWD to monitor pavement strength for the identification the SLR period. The use of innovative sensors and data collection techniques are proving to be very informative and are advancing pavement engineering knowledge. Moreover, the thesis is aimed at exploring the possibilities of achieving the current objectives of the government DOTs such as TPCS potential for addressing the timber industry in crisis, reduced road maintenance budgets, and global warming increasing road damage.

Numerous glacial advances over the past 2 million years have covered the entire Canadian and Fennoscandian Shield outcrop. During glacial advance and retreat, permafrost is expected to form in front of the glacier. The question of how permafrost and freezing impact the formation and evolution of brines in natural systems may be vital to understanding the chemistry of groundwater in crystalline rocks. Investigations of groundwater conditions beneath thick permafrost can provide valuable information that can be applied to assessing safety of deep, underground nuclear waste repositories and understanding analogues to potential life-bearing zones on Mars. However, very little scientific investigation of cryogenic processes and hydrogeology deep within crystalline systems has been published. The purpose of this research is to evaluate the impacts of thick permafrost (>300m) formation on groundwater chemical and flow system evolution in the crystalline rock environment over geologic timescales. A field investigation was conducted at the Lupin Mine in Nunavut, Canada, to characterize the physical and hydrogeochemical conditions within and beneath a thick permafrost layer. Taliks, or unfrozen channels within the permafrost, are found beneath large lakes in the field area, and provide potential hydraulic connections through the permafrost. Rock matrix waters are dilute and do not appear to affect groundwater salinity. Permafrost waters are Na-Cl and Na-Cl-SO4 type, and have been contaminated with chloride and nitrate by mining activities. Sulfide oxidation in the permafrost may be naturally occurring or is enhanced by mining activities. Basal permafrost waters (550 to 570 mbgs) are variably affected by mining. The less contaminated basal waters have medium sulfate concentrations and are Ca-Na dominated. This is similar to deeper, uncontaminated subpermafrost waters, which are Ca-Na-Cl or Na-Ca-Cl type with a wide range of salinities (2.6 to 40 g•L-1). The lower salinity subpermafrost waters are attributed to dissociation of methane hydrate and drawdown of dilute talik waters by the hydraulic gradient created by mine dewatering. This investigation was unable to determine the influence of talik waters to the subpermafrost zone in undisturbed conditions. Pressures are also highly variable, and do not correlate with salinity. Fracture infillings are scarce and calcite δ18O and δ13C values have a large range. Microthermometry indicates a large range in salinities and homogenization temperatures as well, indicative of a boiling system. In situ freezing of fluids and methane hydrate formation may have concentrated the remaining fluids. Field activities at the Lupin mine also provided an opportunity to study the nature of gases within crystalline rocks in a permafrost environment. Gases were generally methane-dominated (64 to 87), with methane δ13C and δ2H values varying between -56 and -42‰ VPDB and -349 to -181 ‰ VSMOW, respectively. The gases sampled within the Lupin mine have unique ranges of chemical and isotopic compositions compared with other Canadian and Fennoscandian Shield gases. The gases may be of thermogenic origin, mixed with some bacteriogenic gas. The generally low δ2H-CH4 ratios are somewhat problematic to this interpretation, but the geologic history of the site, a metaturbidite sequence, supports a thermogenic gas origin. The presence of gas hydrate in the rock surrounding Lupin was inferred, based on temperature measurements and hydrostatic pressures. Evidence also suggests fractures near the mine have been depressurized, likely due to mine de-watering, resulting in dissipation of methane hydrate near the mine. Modeling results indicate methane hydrates were stable throughout the Quaternary glacial-interglacial cycles, potentially limiting subglacial recharge. The effects of deep permafrost formation and dissipation during the Pleistocene glacial/interglacial cycle to deep groundwaters in the Canadian Shield were also investigated by compiling data from thirty-nine sites at twenty-four locations across the Canadian Shield. Impacts due to glacial meltwater recharge and surficial cryogenic concentration of fluids, which had been previously considered by others, and in situ freeze-out effects due to ice and/or methane hydrate formation were considered. At some Canadian Shield sites, there are indications that fresh, brackish, and saline groundwaters have been affected by one of these processes, but the data were not sufficient to differentiate between mixed, intruded glacial meltwaters, or residual waters resulting from either permafrost or methane hydrate formation. Physical and geochemical data do not support the cryogenic formation of Canadian Shield brines from seawater in glacial marginal troughs. The origin and evolution of Canadian and Fennoscandian Shield brines was explored with a survey of chlorine and bromine stable isotope ratios. The δ37Cl and δ81Br isotopic ratios varied between -0.78 ‰ and 1.52 ‰ (SMOC) and 0.01 ‰ and 1.52 ‰ (SMOB), respectively. Variability of chlorine and bromine isotope ratios decreases with increasing depth. Fennoscandian Shield groundwaters tend to be more enriched than Canadian Shield groundwaters for both 37Cl and 81Br. Other sources and processes which may affect δ37Cl and δ81Br composition are also explored. Primary processes such as magmatic and/or hydrothermal activity are thought to be responsible for the isotopic composition of the most concentrated fluids at each site. Positive correlations between δ81Br, and δ37Cl with δ2H-CH4 and δ13C-CH4 were noted. At this time the cause of the relationship is unclear, and may be a result of changing redox, pH, temperature, and/or pressure conditions during hydrothermal, metamorphic, or volcanogenic processes. The data suggest solute sources and fluid evolution at individual sites would be better constrained utilizing a multi-tracer investigation of δ37Cl, δ81Br, and 87Sr/86Sr ratios comparing fluids, rocks, and fracture filling minerals (including fluid inclusions).

The introduction of the use of Tire Pressure Control Systems (TPCS) to improve the productivity of the Canadian trucking industry is gaining momentum. The imposition of seasonal load restrictions (SLR) on the thaw-weakened secondary roads interrupts the transportation of raw materials to processing facilities For the forestry industry in particular, this has very significant impacts on productivity and costs. FPInnovations-Feric Division (Feric) has investigated the potential for TPCS-equipped trucks to travel with full, legal loading during the SLR period without accelerating road wear and tear. The TPCS monitors and adjusts the inflation pressure of the trucks’ tires while driving and allows the operator to optimize the inflations for changes in loading, travel speed, or road quality encountered in the trip. This thesis describes an investigation to determine whether TPCS can be used to mitigate traffic generated damage to secondary roads and also reduce the need to implement load restrictions. The project involves a partnership with the Ontario Ministry of Transportation Ontario (MTO), Forest Engineering Research Institute of Canada (FERIC), Ontario Ministry of Natural Resources (MNR) and the Centre for Pavement and Transportation Technology (CPATT) located at the University of Waterloo. The thesis will describe the methodology, design, and instrumentation of the two test sites which are located in Dryden, Ontario and Chapleau, Ontario. In addition, repeated Portable Falling Weight Deflectometer (PFWD) testing is being carried out at these sites and the initial results of this examination and associated impacts of the environment and traffic on the road will be presented. This study also involves looking into the reliability of using the portable FWD, offering a lower cost alternative instead of the trailer mounted FWD to monitor pavement strength for the identification the SLR period. The use of innovative sensors and data collection techniques are proving to be very informative and are advancing pavement engineering knowledge. Moreover, the thesis is aimed at exploring the possibilities of achieving the current objectives of the government DOTs such as TPCS potential for addressing the timber industry in crisis, reduced road maintenance budgets, and global warming increasing road damage.

Numerous glacial advances over the past 2 million years have covered the entire Canadian and Fennoscandian Shield outcrop. During glacial advance and retreat, permafrost is expected to form in front of the glacier. The question of how permafrost and freezing impact the formation and evolution of brines in natural systems may be vital to understanding the chemistry of groundwater in crystalline rocks. Investigations of groundwater conditions beneath thick permafrost can provide valuable information that can be applied to assessing safety of deep, underground nuclear waste repositories and understanding analogues to potential life-bearing zones on Mars. However, very little scientific investigation of cryogenic processes and hydrogeology deep within crystalline systems has been published. The purpose of this research is to evaluate the impacts of thick permafrost (>300m) formation on groundwater chemical and flow system evolution in the crystalline rock environment over geologic timescales. A field investigation was conducted at the Lupin Mine in Nunavut, Canada, to characterize the physical and hydrogeochemical conditions within and beneath a thick permafrost layer. Taliks, or unfrozen channels within the permafrost, are found beneath large lakes in the field area, and provide potential hydraulic connections through the permafrost. Rock matrix waters are dilute and do not appear to affect groundwater salinity. Permafrost waters are Na-Cl and Na-Cl-SO4 type, and have been contaminated with chloride and nitrate by mining activities. Sulfide oxidation in the permafrost may be naturally occurring or is enhanced by mining activities. Basal permafrost waters (550 to 570 mbgs) are variably affected by mining. The less contaminated basal waters have medium sulfate concentrations and are Ca-Na dominated. This is similar to deeper, uncontaminated subpermafrost waters, which are Ca-Na-Cl or Na-Ca-Cl type with a wide range of salinities (2.6 to 40 g•L-1). The lower salinity subpermafrost waters are attributed to dissociation of methane hydrate and drawdown of dilute talik waters by the hydraulic gradient created by mine dewatering. This investigation was unable to determine the influence of talik waters to the subpermafrost zone in undisturbed conditions. Pressures are also highly variable, and do not correlate with salinity. Fracture infillings are scarce and calcite δ18O and δ13C values have a large range. Microthermometry indicates a large range in salinities and homogenization temperatures as well, indicative of a boiling system. In situ freezing of fluids and methane hydrate formation may have concentrated the remaining fluids. Field activities at the Lupin mine also provided an opportunity to study the nature of gases within crystalline rocks in a permafrost environment. Gases were generally methane-dominated (64 to 87), with methane δ13C and δ2H values varying between -56 and -42‰ VPDB and -349 to -181 ‰ VSMOW, respectively. The gases sampled within the Lupin mine have unique ranges of chemical and isotopic compositions compared with other Canadian and Fennoscandian Shield gases. The gases may be of thermogenic origin, mixed with some bacteriogenic gas. The generally low δ2H-CH4 ratios are somewhat problematic to this interpretation, but the geologic history of the site, a metaturbidite sequence, supports a thermogenic gas origin. The presence of gas hydrate in the rock surrounding Lupin was inferred, based on temperature measurements and hydrostatic pressures. Evidence also suggests fractures near the mine have been depressurized, likely due to mine de-watering, resulting in dissipation of methane hydrate near the mine. Modeling results indicate methane hydrates were stable throughout the Quaternary glacial-interglacial cycles, potentially limiting subglacial recharge. The effects of deep permafrost formation and dissipation during the Pleistocene glacial/interglacial cycle to deep groundwaters in the Canadian Shield were also investigated by compiling data from thirty-nine sites at twenty-four locations across the Canadian Shield. Impacts due to glacial meltwater recharge and surficial cryogenic concentration of fluids, which had been previously considered by others, and in situ freeze-out effects due to ice and/or methane hydrate formation were considered. At some Canadian Shield sites, there are indications that fresh, brackish, and saline groundwaters have been affected by one of these processes, but the data were not sufficient to differentiate between mixed, intruded glacial meltwaters, or residual waters resulting from either permafrost or methane hydrate formation. Physical and geochemical data do not support the cryogenic formation of Canadian Shield brines from seawater in glacial marginal troughs. The origin and evolution of Canadian and Fennoscandian Shield brines was explored with a survey of chlorine and bromine stable isotope ratios. The δ37Cl and δ81Br isotopic ratios varied between -0.78 ‰ and 1.52 ‰ (SMOC) and 0.01 ‰ and 1.52 ‰ (SMOB), respectively. Variability of chlorine and bromine isotope ratios decreases with increasing depth. Fennoscandian Shield groundwaters tend to be more enriched than Canadian Shield groundwaters for both 37Cl and 81Br. Other sources and processes which may affect δ37Cl and δ81Br composition are also explored. Primary processes such as magmatic and/or hydrothermal activity are thought to be responsible for the isotopic composition of the most concentrated fluids at each site. Positive correlations between δ81Br, and δ37Cl with δ2H-CH4 and δ13C-CH4 were noted. At this time the cause of the relationship is unclear, and may be a result of changing redox, pH, temperature, and/or pressure conditions during hydrothermal, metamorphic, or volcanogenic processes. The data suggest solute sources and fluid evolution at individual sites would be better constrained utilizing a multi-tracer investigation of δ37Cl, δ81Br, and 87Sr/86Sr ratios comparing fluids, rocks, and fracture filling minerals (including fluid inclusions).

Self consolidating concrete (SCC) is defined as an innovative concrete that does not require vibration for placing and compaction and it is able to flow under its own weight, completely filling formwork and achieving full compaction. Although significant amount of research has been carried out regarding the fresh properties, mix design, placing methods and strength of various SCC mixes, only a very limited amount of work has been done to assess the durability performance of SCC. Concretes in cold climates are subjected to freeze-thaw cycles which are one of the major durability problems, and if the concrete is in a saturated or nearly saturated condition, those cycles lead to expansion of the water in the capillary pores of concrete causing great internal stresses. For a durable concrete subjected to freeze-thaw cycles, an adequate air void system is obtained by using air-entraining admixtures. The performance of the air void system is characterized by air void parameters that are determined using microscopical examination of the concrete microstructure. In this thesis a software tool, based on image analysis of concrete surface, is developed to evaluate the air void parameters of concrete using both American and European standards. Later on, an experimental program is conducted to evaluate the effect of freezing-thawing on self consolidating concrete that contain different percentages of fly ash (FA) and air entraining agents. For this purpose, a total of ten self consolidating concrete mixtures that contain four different contents of fly ash, and three different levels of air entrainment were prepared. During the casting operation, the workability properties of SCCs were observed through slump flow time and diameter, air content, V-funnel flow time, L-box height ratio, and segregation ratio. Hardened properties were evaluated by compressive strength, permeability tests (water absorption, sorptivity and rapid chloride permeability test), freezing-thawing test, resonant frequency test, ultrasonic pulse velocity test. The developed tool was used to characterize and evaluate the effects of air void parameters of SCC on its resistance to freeze-thaw cycles. At the end of this experimental investigation, it was concluded that the addition of air entraining agent increased the flowability and an increase in the fly ash content decreased the effect of air entraining agent. On the other hand, during image processing, it was observed that the surface preparation procedures have a crucial effect on processing quality. Moreover, spacing factor -which is the most important air void characteristic that is utilized for determination of the resistance to freezing-thawing- should not be restricted to 0.2 mm for SCC, since SCCs with spacing factors smaller than 0.4 mm could still exhibit good freezethaw resistance.