Os peitos de galinhas matrizes pesadas de corte, poedeiras comerciais brancas e frangos foram desossados manualmente, com o objetivo de avaliar e comparar as propriedades tecnológicas – capacidade de retenção de água e de emulsificação – bem como pH e composição centesimal, além de elaborar e avaliar sensorialmente um produto reestruturado empanado, tipo nugget. Os resultados das análises indicaram que não houve diferença significativa entre as carnes analisadas, nem entre produtos processados, implicando utilização regular desse tipo de matéria-prima na indústria de alimentos. O restante das carcaças das galinhas foi utilizado para extração de carne mecanicamente separada (CMS) para avaliação da estabilidade microbiológica. As CMSs foram submetidas a dois tratamentos: I) com 150ppm de nitrito, embaladas em saco de polietileno; e II) com 150ppm de nitrito e 500ppm de eritorbato, embaladas em saco de polietileno. Como controle, as amostras de CMS foram apenas acondicionadas em sacos de polietileno. Todas as embalagens foram estocadas e congeladas a –18ºC por 99 dias. Os resultados da análise de caracterização microbiológica indicaram que tanto as amostras de CMS de galinha matriz quanto de galinha poedeira atenderam os padrões de contagem requeridos pela legislação Brasileira. A avaliação da estabilidade microbiológica das CMSs no primeiro e no último dia para mesófilos, Escherichia coli, Staphylococcus aureus, Clostridium perfringens e Pseudomonas, bem como as análises quinzenais de microrganismos psicrotróficos, indicaram que não houve uma redução significativa nas contagens, independentemente do tratamento aplicado. Não foi detectada Salmonella em nenhuma das amostras analisadas. Tais resultados apontaram o tempo de estocagem como o principal fator na redução da carga bacteriana. / The breasts of heavy fowls, white commercial egg-layers and chickens were manually deboned in order to evaluate and compare technological properties—water hold and emulsifying capacity—and pH and centesimal composition, as well as to prepare and assess a restructured coated product. The results of the analyses indicated that there was not a significant difference between the meats analyzed, nor among the processed products, implying the regular use of such meat in the food industry. The remaining parts of the hens’ carcasses were mechanically deboned for the evaluation of microbiological stability. The mechanically deboned meat (MDM) was submitted to two treatments: I) 150ppm of nitrite, packed in polyethylene bags; II) 150ppm of nitrite and 500ppm of erythorbate, packed in polyethylene bags. The control meats were just packed in polyethylene bags. All samples were frozen-stored at –18ºC for 99 days. The results of microbiological characterization indicated that both samples from heavy fowls and egg-layers were in accordance with the Brazilian legislation. MDM microbiological stability evaluation on the first and last days for fecal coliforms, mesophiles, Staphylococcus aureus, Clostridium perfringens and Pseudomonas, as well as the analyses carried out every fifteen days for psychrotrophics bacteria indicated that there was not a significant reduction in the presence of the above, irrespective of the treatment applied. Salmonella was not detected in any of the samples. Such results indicated that freezing storage period was the main factor responsible for the reduction of the bacterial count in MDM.

The Swedish Nuclear Fuel and Waste Management Company (SKB) has developed a method for final disposal of spent nuclear fuel. This technique requires accurate measurement of the residual decay heat of every assembly. For this purpose, depletion codes as well as calorimetric and gamma-ray spectroscopy experimental methods have been developed and evaluated. In this work a prototype analysis tool has been developed to automate the analysis of both calorimetric and gamma-ray spectroscopy measurements. The performance of the analysis tool has been investigated by comparing its output with earlier results and calculations. Parallel to the software development, new measurements on 73 BWR assemblies were performed. The results obtained for the determination of the residual decay heat are presented. Finally, suggestions for further development are outlined and discussed.

Afin d’évaluer les performances du combustible irradié en situation de stockage géologique, des recherches sont menées sur le comportement à long terme des combustibles irradiés (UOx et MOx) en conditions environnementales se rapprochant de celles du site de stockage français. L’objectif de cette thèse est de déterminer si la géochimie de la couche géologique d'argilites du Callovo-Oxfordien (COx) et la corrosion des conteneurs en acier (produisant du fer et de l'hydrogène) ont un impact sur la dissolution oxydante de la matrice (U,Pu)O2 sous radiolyse alpha de l’eau.Des expériences de lixiviation ont été réalisées avec des pastilles de UO2 dopées en émetteurs alpha (Pu) et du combustible MOx MIMAS (non irradié ou irradié en réacteur) afin de mettre en évidence l’influence de l’eau du COx et de la présence de fer métallique sur la dissolution oxydante de ces différents matériaux induite par la radiolyse de l’eau. Les résultats indiquent un effet inhibiteur de l’eau du COx sur la dissolution oxydante de la matrice UO2. D’autre part en présence de fer, deux régimes différents sont observés. Sous irradiation alpha dominante telle que celle attendue en stockage géologique, la dissolution oxydante de la matrice UO2 et du combustible MOx est très fortement inhibée du fait de la consommation des espèces radiolytiques oxydantes par le fer en solution avec précipitation d’hydroxydes de Fe(III) à la surface des pastilles. En revanche, sous forte irradiation beta/gamma comme dans le cas du combustible irradié, les traceurs de l’altération indiquent que celle-ci se poursuit en présence de fer tandis que la concentration en uranium en solution est contrôlée par la solubilité de UO2(am,hyd). Ceci est expliqué par le déplacement du front redox de la surface du combustible vers la solution homogène ne protégeant plus le combustible. Les modèles géochimique (code CHESS) et de transport réactif (code HYTEC) développés représentent correctement les principaux résultats et mécanismes mis en jeu. / To assess the performance of direct disposal of spent fuel in a nuclear waste repository, researches are performed on the long-term behavior of spent fuel (UOx and MOx) under environmental conditions close to those of the French disposal site. The objective of this study is to determine whether the geochemistry of the Callovian-Oxfordian (COx) clay geological formation and the steel overpack corrosion (producing iron and hydrogen) have an impact on the oxidative dissolution of the (U,Pu)O2 matrix under alpha radiolysis of water.Leaching experiments have been performed with UO2 pellets doped with alpha emitters (Pu) and MIMAS MOx fuel (un-irradiated or spent fuel) to study the effect of the COx groundwater and of the presence of metallic iron upon the oxidative dissolution of these materials induced by the radiolysis of water. Results indicate an inhibiting effect of the COx water on the oxidative dissolution. In the presence of iron, two different behaviors are observed. Under alpha irradiation as the one expected in the geological disposal, the alteration of UO2 matrix and MOx fuel is very strongly inhibited because of the consumption of radiolytic oxidative species by iron in solution leading to the precipitation of Fe(III)-hydroxides on the pellets surface. On the contrary, under a strong beta/gamma irradiation field, alteration tracers indicate that the oxidative dissolution goes on and that uranium concentration in solution is controlled by the solubility of UO2(am,hyd). This is explained by the shifting of the redox front from the fuel surface to the bulk solution not protecting the fuel anymore. The developed geochemical (CHESS) and reactive transport (HYTEC) models correctly represent the main results and occurring mechanisms.

The aim of Diploma thesis was the cultivation of microorganisms Lactobacillus plantarum CCM 7039 and Bacillus coagulans CCM 2658 on hydrolysed spent coffee grounds, production of lactid acid and modelling of these processes to find out more detailed characteristics. First, both microorganisms were cultivated in Erlenmeyer flasks on spent coffee grounds hydrolysate containing lipids and processed by extraction of lipids, e.g. lipid-free. The effect of nitrogen source and inoculation medium were monitored in the course of cultivation. The optimal conditions found were used for subsequent fermentation in bioreactors. Further, microorganisms were cultivated in the Erlenmeyer flasks in the media with individual carbohydrates typical for hydrolysed spent coffee grounds to determine its ability to utilize these carbohydrates. By fermentation in the bioreactors, the yield of lactic acid from carbohydrates was 97 % in Lactobacillus plantarum and 99 % in Bacillus coagulans, respectively. Models for growth and productivity of microorganisms were processed in MATLAB using logistic, generalized logistic and Monod functions. In general, the best data fit was achieved using a logistic function.

The master thesis addresses the issue of cultivation of selected strains of carotenogenic yeasts on waste materials of the food industry using a laboratory bioreactor. Carotenogenic yeasts are able to produce highly valuable metabolites during cultivation, which are located predominantly in the lipid part of the cells. Particularly, they are carotenoids, ergosterol, coenzyme Q and fatty acids. The thesis is divided into two main parts, the theoretical part and the practical part. The theoretical part describes individual yeast strains, types of waste materials, produced metabolites and methods of their analysis. The experimental part deals with the processing of waste materials of the food industry, specifically animal fat, whey and spent coffee grounds into the form of substrates usable as nutrition sources for yeast cultivation. Furthermore, cultivations focused on the recovery of the monitored metabolites and their analysis by using HPLC/PDA and GC/FID assemblies were studied as well. The yeast strains Rhodotorula mucilaginosa (CCY 19-4-6), Rhodotorula kratochvilae (CCY 20-2-26), Rhodosporidium toruloides (CCY 062-002-001), Sporidiobolus pararoseus (CCY 19-9-6) a Cystofilobasidium macerans (CCY 10-1-2) were used in this work. As one of the best producing strains Sporidiobolus pararoseus (CCY 19-9-6) was found, which achieved very high productions of carotenoids, coenzyme Q and ergosterol.

The aim of my thesis was to develop a comprehensive study on the energy use of the coffee waste called spent coffee grounds. The study conducted a complete fuel analysis, TGA analysis, experimental drying and pelletization, combustion tests and basic economic evaluation.

<div>Thermochemical processing using fast-pyrolysis technology has been used to upgrade feedstocks like biomass and natural gas and more recently studied for plastic recycling. This work aims to improve the selectivity to desired products from a pyrolysis process through better catalysts and reactor design.</div><div>Fast-pyrolysis of biomass to fuels is considered a promising technology due to the higher yields to liquid fuel products. However, the process suffers from low carbon efficiency to hydrocarbon products due to carbon losses to biochar, accounting for 25-40 wt.% of the product stream depending on the biomass type. Using a combination of inorganic free-model compounds, biomass pretreatments and mass spectrometric analyses coupled with lab-scale reactor experiments, the char contribution from the lignocellulosic components (cellulose, hemicellulose, and lignin) and mineral content was investigated. The lignocellulosic components were found to follow the order: Lignin > Hemicellulose > Cellulose. Addition of inorganic salts (K, Na and Ca) to cellobiose, a model compound for cellulose, was found to catalyze additional dehydration reactions on primary pyrolysis products (e.g., levoglucosan) to yield secondary products (e.g., 5-HMF), and produce more char. This knowledge of char formation contributors can enable optimization of the bio-refining process sequencing using process system engineering tools and thus achieve higher carbon efficiency for biomass conversion.</div><div>While biomass has been viewed as a future energy source, there is a need for a transition fuel with the lowest possible greenhouse gas (GHG) footprint. Shale gas, consisting primarily of methane, is a potential candidate due to its large availability and high hydrogen to carbon ratio. Recently, single-atom catalysts have been studied as stable and non-coking catalysts for the non-oxidative coupling of methane (NOCM) to higher hydrocarbons (like ethylene). However, lack of post reaction catalyst characterization and rigorous kinetic testing have raised questions on the stability of these materials. This work combines homogenous (Chemkin simulations, gas phase kinetics) and heterogeneous reaction kinetic studies (reaction orders, steady state kinetics), coupled with microscopy (Scanning and Transmission Electron Microscopy (SEM, TEM)) and surface characterization tools (BET, TGA, Raman spectroscopy, CO-IR spectroscopy) to understand the role of the solid materials during NOCM. Post reaction catalyst characterization using transmission electron microscopy (TEM) analysis on the spent samples (CH4 treated at 975 deg C for 3 hours) reveals that the materials containing Pt single atoms (SA) and Pt nanoparticles (NP) are found to sinter to particles approximately 5-7 nm in size. Ethylene hydrogenation experiments, a kinetic probe for surface Pt, shows initial ethane formation rates that are four orders of magnitude lower on the isolated Pt+2 sites, found on Pt SAs, when compared to the rates obtained if all the surface Pt were assumed to be metallic. These results suggest that single atoms are not the active sites. However, under same reaction conditions (50 mL min-1 CH4 flow and 975 deg C), the ethylene formation rates (in mol h-1) on the solid materials are 2-7 times higher than the empty tube rates, indicating that the surface plays a role during NOCM. Addition of incremental amounts of the solid material increases methane conversion, extrapolating to the bare tube conversion at zero loading. This indicates that the solid materials improve the NOCM performance.</div><div>Experiments with pure methane feeds indicate that the solid materials are found to deactivate due to coking on the surface, evidenced by the coke buildup observed using thermogravimetric analysis (TGA) and the initial time-on-stream kinetic results showing rapid methane deactivation. Raman spectroscopy on the spent catalysts indicate at the development of a similar graphite-like surface intermediate under steady state conditions on all the materials. When compared under the same reaction conditions (975 deg C, 60 mL min-1 Pure CH4 with 10% UHP N2 feed, space velocity = 39.6 L h-1 gcat-1), these coked surfaces show a linear dependence for the ethylene formation rate (in mol h-1 gcat-1) with the spent surface area of the material (in m2 gcat-1). This observation is irrespective of the type of the material studied (alpha Al2O3, Davisil SiO2, 1 wt.% Pt/CeO2, Graphene, Graphite, etc.). In conclusion, these results prove that the spent surface area is critical for NOCM.</div><div>Similar experimental setup was used to study the dehydrogenation of methane, ethane, and propane mixture in the gas phase. Initial experiments at 1 bar pressure and reaction temperatures ranging from 650-850 deg C revealed that ethylene and hydrogen are the main gas phase products, with methane acting as a diluting agent under these reaction conditions. These results could enable direct processing of the shale gas without the use of a conventional ethane/propane separation step. These results were further studied by the system engineers using ANSYS ChemkinPro. For practical applications, these experiments were suggested to be performed at much higher operating pressures (~30 bar) and low residence time (~0.2 s), with a quick quenching step added after the reactor to prevent change in the exit stream compositions. A new reaction system was built to experimentally validate these recommendations.</div>

À partir d’une série d’entretiens ethnographiques auprès d’employés des bars et restaurants de Montréal, je me penche dans cette recherche sur le monde de « l’industrie » de la restauration. Au cours de l’enquête, j’identifie un style de vie spécifique composé de ce que j’appelle des « conduites dépensières ». Il s’agit pour ces employés d’un ensemble de pratiques ayant pour conséquence la dépense d’une partie importante de leurs revenus d’emplois dans les restaurants et les bars afin de s’offrir des soirées sociables alcoolisées et des sorties de découvertes gastronomiques. En tentant de rendre compte de ce style de vie, j’avance l’hypothèse que ces conduites sont sous-tendues par un véritable système culturel de coutumes, rituels, normes et valeurs. Au cœur de ce système culturel se trouve le brouillage des frontières entre le professionnel et le privé, le sérieux et le plaisir, le travail et le party. Ce brouillage a pour effet de rediriger une partie des revenus de mes informateurs à l’intérieur de leur univers professionnel. Cette redirection ne serait possible sans le marquage symbolique de l’argent-pourboire, tel que théorisé par Viviana Zelizer, qui fait en sorte que cette monnaie est socialement assignée à la dépense à l’intérieur de « l’industrie ». Au cœur de ma méthode d’enquête se trouve l’utilisation du feuilleton sociologique, véritable outil de validation et de construction des données. / Based on a series of ethnographic interviews with bar and restaurant staff in Montreal, I examine in this study the world of the restaurant “industry.” During the investigation, I have identified a specific lifestyle characterized by “spendthrift conducts.” These conducts are a set of behaviors leading to the spending of a significant portion of my informants’ income in gastronomic discoveries and nights of drinking in restaurants and bars. To account for this particular lifestyle, I argue that these behaviors are underpinned by a cultural system of customs, rituals, norms, and values. The blurring of the boundaries between the professional and the private, the serious and the fun, work and party, is central to this cultural system. As a result of this blurring, the informants’ income is reinjected within their professional universe. This would not be possible without the social earmarking of tip, as theorized by Viviana Zelizer. This currency is socially assigned for spending within the “industry.” While writing up this study the sociological feuilleton has turned out to be an original tool for validating and constructing data.

No description available.

Recently, Sustainable engineering has become a necessity due to the limited availability of virgin materials, environmental concerns, and the lack of economic resources. According to the United Nations, "Sustainable engineering is the process of using resources in a way that does not compromise the environment or deplete the materials for future generations." However, developing cost-efficient and long-term road infrastructure has always been a challenge. Therefore, novel solutions are required to extend the pavement life cycle and minimize raw materials utilization to overcome this challenge. This research focuses on integrating the waste material to produce rheological engineered asphalt mixtures as pavement material. This study utilized three wastes, which are Off-spec fly ash (OFA), Reclaimed Asphalt Pavement (RAP), and finally, a bio-oil extracted from Spent Coffee Ground (SCG). OFA is a viable source for recycling due to the quantities produced yearly and deposited in landfills. For many years fly ash has been effectively used as a partial replacement for Portland cement in producing different types of concrete, embankments, and soil stabilization. Most of the underutilized fly ash is Off-Spec. That was the motive behind adopting the OFA in this study. This study aims to investigate the fly ash's interaction with the asphalt binder as an additive rather than a filler. Few studies evaluated this hypothesis regarding fly ash as an additive. Moreover, this research's novelty comes as there is a lack of research evaluating the fly ash-asphalt physio-chemical interaction. RAP utilization in roads infrastructure became a current state of practice. Most state Departments of Transportation (DOTs) have been using RAP at a composition average of about 20% of the mix by mass. This study focuses on maximizing the utilization of the RAP content through using a bio-oil extracted from the SCG as a new promising rejuvenator. Spent coffee ground is not well recycled, and almost six million tons are sent to landfills every year. This waste was found to release methane into the atmosphere; methane is the second-most abundant greenhouse gas and has a global warming potential up to 86 times greater than CO2, which is highly harmful to the environment. In this study, the overreaching goal is to develop a green, innovative, and sustainable approach by recycling three different types of wastes (OFA, RAP, and SCGO) to achieve high-performance asphalt pavements. In addition, this study documents the science-based approach to successfully integrating these wastes as substitutes to the asphalt binder. Results show that some OFAs are associated with improved rheological performance, damage healing, and cracking resistance as an asphalt binder additive. The improvement is attributed to the level of interaction between the binder and the physical and chemical characteristics of the OFA. The use of rejuvenators further improved the aging resistance of the ash blends, suggesting high potential synergy, especially the proposed SCGO rejuvenator, which promotes utilizing it as a promising eco-friendly rejuvenator in the asphalt pavement industry. After engineering a product built by OFA and rejuvenators, these results have been validated by mixtures’ scale testing. 62% optimum RAP content is suggested to be utilized with an 11% dosage of the proposed SCGO rejuvenator as binder replacement. For the new engineered OFA/rejuvenators products, a 30% optimum RAP content is suggested to be used. Finally, Life Cycle Assessment (LCA) is conducted to evaluate the environmental potential of utilizing multi recycled materials in the Hot Mix Asphalt (HMA) industry. The results show a reduction in environmental impacts with RAP utilization and the new eco-friendly products (OFA and SCGO rejuvenator). Shifting HMA plant fuel to natural gas instead of Heavy Fuel Oil (HFO) offers considerable potential environmental benefits. Adopting the Ultrasonic Assisted-oil Extraction (UAE) as SCGO rejuvenator extraction method showed less energy and solvent consumption than the Soxhlet extraction, resulting in less environmental impacts. / Civil Engineering