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Thermally Sensitive and Tunable Water-Soluble Polymer Molds for the Preparation of Porous Hydrogels
No full textComparative analysis of classical and ensemble models for predicting whole body vibration induced lumbar spine stress. A case study of agricultural tractor operators
No full textSimulation of Wave Breaking Impact Forces on Walls Using the Cahn-Hilliard Navier-Stokes Equations
No full textIn this paper, we address the numerical simulation of wave-breaking impact forces on walls in the context of membrane LNG sloshing applications. Traditional front-tracking (ALE) methods provide a precise representation of the free surface under moderate deformations, yet can struggle with topological changes such as droplet formation, merging, and fragmentation. To capture these complex interface dynamics, we propose and validate a Cahn–Hilliard–Navier–Stokes (CHNS) formulation integrated into the finite element solver CADYF. By comparing the results of both approaches—front-tracking and diffuse-interface—on key test cases (including Rayleigh–Taylor instability, a large gas-pocket impact scenario, and a piston-generated breaking wave), we demonstrate consistent predictions in terms of free-surface shapes. The CHNS method naturally accommodates strong topological changes but requires careful calibration of parameters and local mesh refinement for high accuracy. The front-tracking approach, on the other hand, excels at sharply imposing jump conditions whenever the interface remains continuous. Overall, the two strategies exhibit complementary strengths, and their agreement in wave-impact benchmarks underlines the reliability of CADYF for sloshing-related flows. Ongoing and future work will refine the CHNS approach using adaptive remeshing, extend validations against experimental data, and further explore free-surface instabilities and fragmentation phenomena to enhance predictions of impact loads in LNG membrane tanks and related applications.General Context. The general context of this study is the sloshing assessment of membrane LNG tanks on floating structures thanks to sloshing model tests. The flows of liquid and gas within the model tank are not in complete similarity with the flows within the LNG tank because the fluids properties, other than their densities, do not match the right values to comply with the relevant similarity laws. Therefore, it is important to understand the influence of the different biases on the long-term statistics of pressure measurements when a complete similarity is assumed to enable up-scaling the pressures by dimensional analysis
Enhanced O-glycosylation site prediction using explainable machine learning technique with spatial local environment
No full textContexte tectono-magmatique de mise en place de carbonatites minéralisées en éléments des terres rares dans la Zone de Bordure de la Ceinture métasédimentaire centrale au Québec
Get PDFRÉSUMÉ: « RÉSUMÉ: Plusieurs carbonatites minéralisées en éléments des terres rares (ETR) ont été identifiées le long d’une importante zone de déformation traversant le Québec et l’Ontario, c.-à-d. la Zone de Bordure de la Ceinture métasédimentaire centrale (CMBBZ). Dans le cadre de travaux géoscientifiques antérieurs, ces carbonatites et leurs roches silicatées associées ont été décrites comme étant génétiquement liées à la Suite Intrusive de Kensington-Skootamatta, une suite alcaline potassique située à proximité. Selon des données géochronologiques, cette suite aurait été mise en place entre environ 1090 et 1070 Ma, coïncidant avec le début présumé de la collision continentale à l’origine de l'Orogénie grenvillienne. Cette étude a pour objectif de déterminer le contexte tectono-magmatique de mise en place des carbonatites de la CMBBZ, et d’établir des contraintes géochronologiques sur les évènements syn- et post-déformation au sein de cette zone. La géochronologie U-Pb par spectrométrie de masse à plasma à couplage inductif avec ablation laser (LA-ICP-MS) sur zircon provenant de sept échantillons fournit des âges 207Pb/206Pb de : (1) 1193 ± (5) [erreur analytique uniquement : erreur non propagée] 16 [erreur incluant les incertitudes systématiques : erreur propagée] Ma pour une pegmatite syéno-granitique pré- à syn-déformation; (2) 1162 ± (5) 16 Ma pour un leucosome à orthopyroxène syn-déformation situé dans le quadrant extensif d'un boudin mafique cisaillé; (3) 1157 ± (4) 16 Ma pour une pegmatite syénitique syn-déformation caractérisée par des micro-textures indicatives de liquide carbonatitique mettant en évidence une mise en place syn-déformation des carbonatites de la CMBBZ; (4) 1149 ± (12) 18 Ma pour une pegmatite syéno-granitique tardi-déformation; (5) 1053 ± (13) 18 Ma, (6) 1027 ± (11) 16 Ma et (7) 1022 ± (6) 15 Ma pour trois dykes post-tectoniques. Ces résultats, corroborés par des observations de terrain et au microscope, ainsi que des données géochimiques, montrent que la formation des carbonatites minéralisées en ETR le long de la CMBBZ n’est pas liée à la Suite Intrusive de Kensington-Skootamatta. Cependant, les résultats révèlent que ces carbonatites sont issues d’un évènement convergent plus ancien: l’Orogénie Shawinigan (ca. 1190-1140 Ma). Par ailleurs, la fusion partielle associée à une zone en subduction avant ou lors de cette orogenèse pourrait avoir joué un rôle clé dans la pétrogenèse de ces intrusions.» ABSTRACT: «ABSTRACT: Several rare earth element (REE)-bearing carbonatite occurrences have been identified along a significant deformation zone going across Quebec and Ontario, i.e., the Central Metasedimentary Belt Boundary Zone (CMBBZ). In previous geoscientific studies, these carbonatite occurrences and their associated silicate rocks were described as being genetically linked to the Kensington-Skootamatta Intrusive Suite, an alkaline potassic suite located nearby. According to geochronological data, this suite was emplaced between approximately 1090 and 1070 Ma, coinciding with the presumed onset of the continental collision that led to the formation of the Grenville Orogen. This study aims to elucidate the tectono-magmatic context of carbonatite emplacement along the CMBBZ and to establish geochronological constraints on syn- and post-deformation events within this zone. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb geochronology on zircon from seven samples yields 207Pb/206Pb ages of: (1) 1193 ± (5) [analytical error only: non propagated error] 16 [error including systematic uncertainties: propagated error] Ma for a pre- to syn-deformation syeno-granitic pegmatite; (2) 1162 ± (5) 16 Ma for a syn-deformation orthopyroxene leucosome located in the extensional quadrant of a sheared mafic boudin; (3) 1157 ± (4) 16 Ma for a syn-deformation syenitic pegmatite characterized by micro-textures indicative of carbonatitic melt, providing evidence for a syn-deformation emplacement of carbonatites along the CMBBZ; (4) 1149 ± (12) 18 Ma for a late-deformation syeno-granitic pegmatite; (5) 1053 ± (13) 18 Ma, (6) 1027 ± (11) 16 Ma, and (7) 1022 ± (6) 15 Ma for three post-tectonic dykes. These results, corroborated by field and microscopic observations, and geochemical data, show that the formation of REE-bearing carbonatites along the CMBBZ is not related to the Kensington-Skootamatta Intrusive Suite. However, results indicate that these carbonatites originated from an older convergent event: the Shawinigan Orogeny (ca. 1190-1140 Ma). Furthermore, slab-melting prior to or during this orogeny may have played a key role in the petrogenesis of these intrusions.
Electrifying greenhouse agriculture: Cold atmospheric pressure plasma technology for Pythium ultimum control
Get PDFABSTRACT: Hydroponic growth of food plants in greenhouses is of rapidly increasing importance to assure future autonomy of food supply, especially in harsher climate zones. Greenhouse culture yields are drastically reduced by pathogenic microorganisms that cause root rot in plants. In Canada, the fungus Pythium ultimum, which can survive harsh winter conditions, has a particularly large impact on food production. In this work, we present cold physical plasma treatment of liquids with a gliding arc plasma as a novel approach for combating pythium growth in liquid media. This study is based on exploring air or other N₂ + O₂ mixtures as a parameter to identify which plasma treatment is best suited for its anti-fungal activity in different media. If sourced from renewable energy and water, the proposed treatment is intrinsically sustainable. 3 media conditions are explored: first distilled water, to identify the production of highly reactive oxygen species (ROS) and reactive nitrogen species (RNS). Second, an inoculated distilled water is used in conjunction with an ELISA assay as a quick response indicator. Third, a Sabouroud 2 % dextrose broth, is used as a culture media in which oomycetes are grown subsequent to plasma treatment, and hyphal mass is compared between untreated and treated samples. Extracting a subset of 80+ chemical reactions from the available literature and databases, a reaction scheme is proposed accounting for liquid-vapor equilibria (through Henry’s coefficients) and reaction rate analysis. The most promising plasma treatment condition was found to be using a 95 % N₂: 5 % O₂ gas mixture with a treatment time of 30 min, reducing hyphal mass growth from 1.8 g to 0.4 g over 1 week in Sabouroud broth. The pythium degradation process was observed through scanning electron microscopy (SEM) analysis, showing that Sporangium or oogonia containing structures that terminate the pythium’s hyphae have been broken and significantly reduced after plasma treatment
Code and Data Repository for Solving Two-Stage Stochastic Programs with Endogenous Uncertainty via Random Variable Transformation
No full textPath Tracking Error Minimization of Differential Drive Wheel Mobile Robot Carrying Off-Center Heavy Load
No full textPersonalized Assistance in Robotic Rehabilitation: Real-Time Adaptation via Energy-Based Performance Monitoring
No full textModeling marine microplastic emissions in life cycle assessment: characterization factors for biodegradable polymers and their application in a textile case study
Get PDFABSTRACT: Introduction: With the continuous increase of plastics production, it is imperative to carefully examine their environmental profile through Life Cycle Assessment (LCA). However, current LCA modeling is not considering the potential impacts of plastic emissions on the biosphere. To integrate plastic emissions into LCA, characterization factors are needed that commonly consist of three elements: a fate factor, an exposure factor, and an effect factor. In this context, fate factors quantify the distribution and longevity of plastics in the environment. Research on these fate factors is still limited, especially for biodegradable polymers. Hence, the main objective of this research was to determine the fate factors of biodegradable polymers [poly (lactic acid), poly (butylene succinate), and poly (ε-caprolactam)] based on primary experimental data for the marine environment. Methods: The validity of former research is tested by comparing the degradation evolution of i. macro- and microplastic particles, ii. two different grades of the polymer, and iii. different temperature levels. The degradation data are obtained by monitoring the oxygen consumption over a period of six months in natural seawater. The determined degradation rates are combined with sedimentation, resuspension, and deep burial rates to obtain fate factors. These fate factors are used to develop polymer-specific characterization factors. The resulting characterization factors are tested in an LCA case study of a synthetic sports shirt made from biodegradable polymer fibers. It allows to assess the relative importance of microplastic impacts compared to other life cycle impacts. Results and discussion: Comparing the resulting specific surface degradation rates indicates that microplastic degradation rates could be overestimated when using macroplastic degradation data. Pertaining to the case study, the results show that the impact on ecosystem quality by microplastic emissions could account for up to 30% of the total endpoint category. Overall, this work aims to foster interdisciplinary collaboration to leverage the accuracy of LCA studies and thus provide guidance for novel material development