The longitudinal solute transport modeling is critical in river and stream water quality management, control, and the mitigation of hazardous riverine spills. One of the widely used "deadzone" model is the transient storage model (TSM). TSM is a significant improvement over the advection-dispersion model (ADM), but it cannot simulate the breakthrough curve (BTC) immediately after a large pool. Additionally, the calibration (parameterization) method is challenged by the non-identifiability which is common to all inverse modeling, and it seems TSM cannot be easily used as a predictive tool, more of an interpretive tool of solute transport, i.e., is the parameter set calibrated via inverse modeling transferable? Pools are fundamental stream morphology unit in streams with mixed bed materials in pool-riffle or pool-step sequences. Understanding of how a pool impacts the longitudinal solute transport is the first step towards improving current model such as TSM or developing new models. By introducing a dimensionless group, e= Q/(Dt W) (where, Q is the average volumetric flow rate; Dt is an average transverse dispersion coefficient; W is the channel flow width), derived from non-dimensionalization of the governing equations of one of the most rigorous 2-dimansional (2D) (depth-averaged) model, Mike21, this work presents an alternative way of longitudinal solute transport investigation. Using the 2D fully hydrodynamic Mike21, numerical experiments were conducted on hypothetical streams in this dissertation. Simulation study on hypothetical stream with pool reveals that a pool's effects on longitudinal solute transport are manifested by three aspects: boosting longitudinal spreading (concentration peak attenuation), causing a solute plume delay and increasing solute residence time. These effects fade like a "wake" as the solute plume moves downstream. e provides an insight into the physics of longitudinal transport; it outlines a relative transverse mixing intensity of a stream. The internal transport and mixing condition (including the secondary circulations) in a pool together with the pool's dimensions determine the pool's storage effects especially when e >>1. The BTCs downstream from a pool may be "heavy tailed" (i.e., have enormously slow decaying rate) which cannot be modeled by the TSM. Results also suggest that the falling limb of a BTC more accurately characterizes the pool's storage effects because the corresponding solute has more chance to sample the entire storage area. n a more fundamental perspective, the predictive ability of inverse modeling parameterized model is discussed and conclusion is made about the role of a stream/river system's nonlinearity in determining the predictability; a misleading mis-nomenclature in TSM application is also demonstrated with a numerical experiment. / Civil Engineering

Doctor of Philosophy / Department of Biological & Agricultural Engineering / Naiqian Zhang / Suspended sediment concentration (SSC) in water is one of the most important parameters to evaluate water quality. Monitoring SSC provides important information on determining sediment transport for soil erosion research and soil/water conservation practices. Sediment mass transported at a given time can be assessed by simultaneous SSC and water flow velocity measurements. Fouling, including bio-fouling, has damaging impact on optical SSC measurements over the long term. In this study, an inexpensive, real-time, self-cleaning, optical sediment and flow velocity sensor was developed. Laboratory experiments were conducted on a previously designed SSC sensor. A light modulation algorithm was designed to reduce the influence of ambient light, especially sunlight, on measurement accuracy. Statistical models to predict SSC based on measured light intensities were established and compared with neural network models. The statistical analysis showed that soil texture played an important role in SSC measurement accuracy while the designed sensor was capable of reducing the effect of water color on sensor performance. Neural-network models can further remove the influence of soil texture type on SSC measurement. The sensor design was simplified based on a stepwise selection analysis. Long-term field experiments were conducted in Kansas and Georgia to evaluate the sensor performance, the effect of fouling, including bio-fouling, on sensor lenses, and the effect of temperature on the measurement. Methods of removing the fouling effect through data correction were developed. Results indicated that the designed optical SSC sensor was capable of providing rapid response to SSC fluctuations in water flow. Temperature of the water body has an insignificant impact on SSC measurement. In order to reduce fouling, an air-blast cleaning mechanism was integrated into the optical sediment sensor. Laboratory experiments in a manually created fouling environment were conducted to observe the fouling process on sensor cases made of different materials, and to verify the effectiveness of air-blast cleaning in reducing fouling. Results indicated that air-blast cleaning mechanism was capable of reducing clay/silt fouling on sensor signals. The duration and frequency of air-blast cleaning can be determined and adjusted depending on actual field conditions. An air pressure drop test was conducted on the hose carrying pressurized air. Results showed negligible pressure drop.A flow velocity measurement function based on the cross-correlation principle was integrated into the optical sediment sensor. An experiment was conducted in laboratory to examine the sensor performance on velocity measurement using a closed circulation system. A solution of blue colorant, Brilliant Blue FCF, was used as an artificial source to absorb light emitted by LEDs in the sensor and the signal variation patterns were measured. The results indicated that the cross-correlation-based velocity sensor was capable of measuring water flow velocity within in a certain velocity range using the dye injection method.

Master of Science / Department of Biological & Agricultural Engineering / Gary A. Clark / This report presents the methods to determine the minimum number of collectors to accurately measure the coefficient of uniformity and the average depth of applied water from fixed plate and moving plate center pivot sprinkler irrigation systems. This research conducted an uniformity analysis and an average depth analysis. In the uniformity analysis, catch can collected data from center pivot system tests were divided into base sets of 60 data points. Each base set was further divided into subsets of 30 data points each. T-tests were used to compare the CU values from the base data sets with CU values from each of the subsets. In the average depth analysis, center pivot system catch can data were divided into base sets with 20 data points. Each base data set was divided into 19 subsets. The 1st subset was generated by removing an exterior data point from the base set which was identified by number 1. The 2nd subset was generated by removing other exterior data point (identified by number 20) from the previously generated subset (1st subset). In this manner, a total of 19 subsets for each base set were generated by removing an exterior point from each previous subset. The percent difference (change) in average depth of each subset from the value of the average depth of the base set was calculated. The percent difference in average depth was then plotted against the associated number of collectors. Both analyses documented that a decrease in the number of collectors from the original density of collectors is acceptable to determine the uniformity and averaged depth of applied water from center pivot spans. Results from the uniformity analysis demonstrated that 20 collectors were as effective as 60 collectors to quantify the uniformity of a system. The depth analysis showed that 9 to 12 collectors may be needed to measure the average depth of a system (or a portion of a system) to within 5% to 7.5% of the true value.

Aujourd’hui, il existe très peu de nouveaux produits écoconçus (NPE) mis sur le marché par les PME du Québec et les réussites commerciales sont encore plus rares. Dans ce contexte, il semble pertinent de se pencher sur la manière dont le processus d’écoconception pourrait être à la fois mieux et plus utilisé dans les PME québécoises en étudiant spécifiquement la réception des NPE auprès des détaillants pendant la commercialisation. La question à laquelle se propose de répondre ce mémoire est la suivante : comment un produit conçu selon une approche cycle de vie est-il reçu par le réseau de détaillants d’une PME? Aussi, cette recherche explore le rôle du designer, qui normalement s’achève au début de la commercialisation, que pourrait jouer durant cette phase afin de favoriser la réception positive d’un NPE. Cette recherche s’appuie sur une étude de cas de la première phase de commercialisation d’un meuble de salle de bain écoconçu par une PME manufacturière québécoise en 2010 et 2011. La chercheuse a observé la réception d’un NPE, c’est-à-dire la perception et l’appréciation de celui-ci, par des personnes œuvrant dans une PME de fabrication d’ameublement de salle de bain et par ceux qui agissent dans son réseau de distribution. Nous avons relevé que la compréhension des notions liées à l’écoconception est un enjeu important dans la réception d’un NPE. C'est pourquoi la formation des détaillants et l’éducation des consommateurs deviennent essentielles pour la réception positive d’un NPE. Dans cette perspective, le designer pourrait intervenir durant la commercialisation. / There are still very few new eco-designed products (NEP) commercialized by SMEs and commercial successes are even more rare in Quebec. In this context, this study examines how the eco-design process could be integrated more easily with people working in SMEs in Quebec, specifically studying the retailer’s reception of NEP during the commercialization. Therefore, a major question from this dissertation in learning research is: how a product designed according to the life cycle approach is received by the SMEs’ network of retailers? Also, our research explores how the role of designer, which normally ends at the beginning of the commercialization, could evolve during this phase to help receive a NEP. This case study, examines the first phase of the commercialization of bathroom furniture eco-designed by a Quebec manufacturing SME in 2010 and 2011. The researcher observed the reception of a NEP, which in summary translates in the perception and appreciation of NEP. These observations were lead with people working in an SME manufacturing bathroom furniture and with people working in his network of retailers. It was observed that the understanding of the notion of eco-design is an important issue in the reception of a NEP. For this reason, the training of the retailers and the education of the consumers are an essential part for the positive reception of a NEP. Also, because of his/her knowledge of eco-design, the designer could become a major contributor during the phase of commercialization.

Master of Science / Department of Chemical Engineering / Larry E. Erickson / Photocatalytic oxidation (PCO) is a promising and emerging technique in controlling indoor air contaminants, including volatile organic compounds (VOCs). It has broad air cleaning and deodorization applications in indoor environments ranging from residential and office buildings to healthcare and nursing facilities as well as spacecrafts, aircraft cabins and clean rooms in the agricultural and food industry. Numerous studies have been conducted to improve the effectiveness and performance of this technology. These include development of new configurations, energy-efficient catalysts and other parameters to control the process. However, only limited research has been conducted under realistic indoor environmental conditions. One of the most recent developments in photocatalysis is the synthesis of 2% C- and V-doped TiO[subscript]2, which is active under both dark and visible light conditions. However, like most research conducted in photocatalysis, the study on the reactivity of this catalyst has been performed only under laboratory conditions. This study investigated the possible application of the novel C and V co-doped TiO[subscript]2 in cleaning indoor air. Mathematical modeling and simulation techniques were employed to assess the potential use of some of the promising systems that utilize the catalyst (i.e., packed bed and thin films) as well as the effect of mass transfer limitations in the degradation of acetaldehyde, one of the VOCs that can be found in offices, residential buildings and other facilities.

CO2 is a waste product from a number of human activities such as fossil fuel power generation, industrial manufacturing processes, and transport. The rising concentration of CO2 in the atmosphere is heating the planet’s surface via the well-established greenhouse effect; a mechanism for many irreversible climate change impacts. Coupled to this is the ever-increasing global pressure over the availability and access to fossil fuel reserves; the foundations of modern society. In recognition of this CO2 is gaining renewed interest as a carbon feedstock, a changing of attitude viewing it as an asset rather than waste. Carbon capture and utilisation (CCU) technologies are attempting to make use of it. However, little quantitative assessment work has been done to assessand verify such potentials. This thesis applies the principles and framework of the life cycle assessment (LCA) - environmental management tool to early stage CO2 utilisation laboratory processes. All processes employ engineered nanomaterials (ENM) to perform this function, a material class leading the way in the challenges of efficient and feasible CO2 chemistry. The LCA contribution in this thesis acts as a measuring and a guiding tool for technology developers, in the first instance to document the cradle-to-gate impacts of a number of formed ENMs. Appreciating the net environmental benefits of ENM uptake within society has yet to be wholly established, and the unavailability of data is recognised as a major factor. The work of this thesis will thus contribute to knowledge gaps, and be informative to wider community seeking to quantify technical performance benefits of ENMs in the context of net life cycle impact burdens. Finally the actual CCU processes are assessed, initially within the confines of the laboratory but further expanded for consideration at more industrially relevant scales. The potential for sound CCU performance were found achievable under best case conditions, with net GHG impact reductions over the life cycle, and the potential for lower impact carbon products, even carbon negative. However other environmental impacts such as ozone depletion, toxic emissions and the consumption of precious metalores are impacts that require consideration in the use of such technologies.

published_or_final_version / Architecture / Master / Master of Landscape Architecture

Aujourd’hui, il existe très peu de nouveaux produits écoconçus (NPE) mis sur le marché par les PME du Québec et les réussites commerciales sont encore plus rares. Dans ce contexte, il semble pertinent de se pencher sur la manière dont le processus d’écoconception pourrait être à la fois mieux et plus utilisé dans les PME québécoises en étudiant spécifiquement la réception des NPE auprès des détaillants pendant la commercialisation. La question à laquelle se propose de répondre ce mémoire est la suivante : comment un produit conçu selon une approche cycle de vie est-il reçu par le réseau de détaillants d’une PME? Aussi, cette recherche explore le rôle du designer, qui normalement s’achève au début de la commercialisation, que pourrait jouer durant cette phase afin de favoriser la réception positive d’un NPE. Cette recherche s’appuie sur une étude de cas de la première phase de commercialisation d’un meuble de salle de bain écoconçu par une PME manufacturière québécoise en 2010 et 2011. La chercheuse a observé la réception d’un NPE, c’est-à-dire la perception et l’appréciation de celui-ci, par des personnes œuvrant dans une PME de fabrication d’ameublement de salle de bain et par ceux qui agissent dans son réseau de distribution. Nous avons relevé que la compréhension des notions liées à l’écoconception est un enjeu important dans la réception d’un NPE. C'est pourquoi la formation des détaillants et l’éducation des consommateurs deviennent essentielles pour la réception positive d’un NPE. Dans cette perspective, le designer pourrait intervenir durant la commercialisation. / There are still very few new eco-designed products (NEP) commercialized by SMEs and commercial successes are even more rare in Quebec. In this context, this study examines how the eco-design process could be integrated more easily with people working in SMEs in Quebec, specifically studying the retailer’s reception of NEP during the commercialization. Therefore, a major question from this dissertation in learning research is: how a product designed according to the life cycle approach is received by the SMEs’ network of retailers? Also, our research explores how the role of designer, which normally ends at the beginning of the commercialization, could evolve during this phase to help receive a NEP. This case study, examines the first phase of the commercialization of bathroom furniture eco-designed by a Quebec manufacturing SME in 2010 and 2011. The researcher observed the reception of a NEP, which in summary translates in the perception and appreciation of NEP. These observations were lead with people working in an SME manufacturing bathroom furniture and with people working in his network of retailers. It was observed that the understanding of the notion of eco-design is an important issue in the reception of a NEP. For this reason, the training of the retailers and the education of the consumers are an essential part for the positive reception of a NEP. Also, because of his/her knowledge of eco-design, the designer could become a major contributor during the phase of commercialization.

Doctor of Philosophy / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Nanostructured particles possess unique chemical and physical properties, making them excellent candidates for air purification, smoke clearing, and obscuration. This research was conducted to investigate the aerodynamic, charging, and infrared (IR) extinction properties of nanostructured particles. Specific objectives were to: (1) measure the size distribution and concentration of aerosolized nanostructured particles; (2) evaluate their IR extinction properties; (3) determine their relative chargeability; and (4) numerically model their transport in enclosed rooms. The size distribution and concentration of two nanostructured particles (NanoActive® MgO and MgO plus) were measured in an enclosed room. The particles differed in size distribution and concentration; for example, the geometric mean diameters of NanoActive® MgO and MgO plus were 3.12 and 11.1 [Mu]m, respectively. The potential of nanostructured particles as IR obscurants was determined and compared with other particles. Four groups of particles were considered: nanostructured particles (NanoActive® MgO plus, MgO, TiO[subscript2]); nanorods (MgO, TiO[subscript2]); conventional particles (NaHCO[subscript3] and ISO fine test dust); and common obscurants (brass, graphite, carbon black). The extinction coefficients of the nanostructured particles were generally significantly smaller than those of the other particles. Graphite flakes had the greatest mass extinction coefficient (3.22 m[superscript2]/g), followed by carbon black (1.72 m[superscript2]/g), and brass flakes (1.57 m[superscript2]/g). Brass flakes had the greatest volume extinction coefficient (1.64 m[superscript2]/cc), followed by NaHCO[subscript3] (0.93 m[superscript2]/cc), and ISO fine test dust (0.91 m[superscript2]/cc). The relative chargeability of nanostructured particles was also investigated. Selected particles were passed through a Teflon tribocharger and their net charge-to-mass ratios were measured. Tribocharging was able to charge the particles; however, the resulting charge was generally small. NanoActive® TiO[subscript2] gained the highest net charge-to-mass ratio (1.21 mC/kg) followed by NanoActive® MgO (0.81 mC/kg) and ISO fine test dust (0.66 mC/kg). The transport of NanoActive® MgO plus and hollow glass spheres in an enclosed room was simulated by implementing the discrete phase model of FLUENT. In terms of mass concentrations, there was reasonable agreement between predicted and measured values for hollow glass spheres but not for NanoActive® MgO plus. In terms of number concentration, there was large discrepancy between predicted and measured values for both particles.

Impact pile driving can produce extremely high underwater sound levels, which are of increasing environmental concern due to their deleterious effects on marine wildlife. Prediction of underwater sound levels is important to the assessment and mitigation of the environmental impacts caused by pile driving. Current prediction methods are limited and do not account for the dynamic pile driving source, inhomogeneities in bathymetry and sediment, or physics-based sound wave propagation. In this thesis, a computational model is presented that analyzes and predicts the underwater noise radiated by pile driving and is suitable for shallow, inhomogeneous environments and long propagation ranges. The computational model uses dynamic source models from recent developments in the technical literature. Pile source models are coupled to a broadband application of the range-dependent acoustic model (RAMPE), a standard parabolic equation (PE) propagation code capable of modeling wave propagation through complex, range dependent environments. Simulation results are shown to be in good agreement with several observations of pile driving operations in the Columbia River between Portland, Oregon and Vancouver, Washington. The model is further applied to extend sound level predictions over the entire river and study the effects of sediment and bathymetry on the underwater sound levels present in the environment.