Miracle-dz/UniFAR-FTUs huggingface dataset:
Three dimensional thermal modelling of high temperature proton exchange membrane fuel cells in a serpentine design

THREE DIMENSIONAL THERMAL MODELLING OF HIGH TEMPERATURE PROTON EXCHANGE MEMBRANE FUEL CELLS IN A SERPENTINE DESIGN L. C. Maasdorp MSc Thesis, Department of Physics, University of the Western Cape In this thesis, I explore the subjects of fluid dynamics and high temperature proton exchange membrane fuel cells, PEMFC. Fuel cells have been found to be at the forefront of providing the world with its much needed alternative energy resource. Despite the already existing applications, a full scale distribution, as to other alternative energy resources, still faces many challenges. Among these challenges is the thermal management of the fuel cell. Unmanaged temperature distribution of a fuel cell affects the cells mechanical stability and durability. The aim of my work is to model a segment of a unit cell of a fuel cell stack using numerical methods which is classified as computational fluid dynamics and implementing the work in a commercial computational fluid dynamics package, FLUENT. The focus of my work is to study the thermal distribution within this segment. The results of the work aid in a better understanding of the fuel cell operation in this temperature range. At the time of my investigation experimental results were unavailable for validation and therefore my results are compared to previously published results published. The outcome of the results corresponds to this, where the current flux density increases with the increasing of operating temperature and fixed operating voltage and the temperature variation across the fuel cell at varying operating voltages. It is in the anticipation of determining actual and or unique material input parameters that this work is done and at which point this studies results
Selection the Drug Efficacy of Oroidin Derivatives as Hsp90 Inhibitors by Computer Aided Drug Design Method

Heat shock protein 90 (Hsp90) is a conserved molecular chaperone associated with regulation of hundreds of client proteins that are key drivers, regulators and promoters of numerous refractory diseases including cancer. Consequently, Hsp90 is a significant target for the development of harmless anticancer therapies. Marine organisms are the rich source of pharmacological important compounds, especially oroidin. Oroidin, a pyrrole-2-aminoimidazole alkaloid, isolated from the marine sponge Agelas oroides, binds ATP pocket of Hsp90 and suppresses the ATPase activity of the protein. Natural product oroidin was selected as potent inhibitor of Hsp90 and its drug candidature was accordingly improved by substituting various functional groups. Virtual screenings were done through in silico studies, carried out on thirty nine derivatives of oroidin. DFT study was performed with Gaussian16, UB3LYP/6-311G++ (d, p) basis set to investigate the quantum mechanical parameters such as HOMO-LUMO energies, dipole moments. Derived parameters like ionization potential, electron affinity, softness-hardness, chemical potential and electrophilicity index were also calculated. Using AutoDock 4.0 programme, we studied docking of the thirty-nine designed derivatives with macromolecule Hsp90 and recorded the binding energy values of the best conformation out of nine in each docked compound. ADME predictions, molecular descriptor properties, and theoretical toxicity tests were evaluated using preADMET, molinspiration, and OSIRIS property explorer web tools respectively. We found twenty eight derived compounds, each docked at the same region of Hsp90, possessing higher binding energies compare to the precursor oroidin. Seven of them qualified all the rules of drug candidature and could be safe in using as effective drugs for cancer treatment. This study suggests that these compounds could be synthesized for in vitro test and may leads to a novel anticancer therapeutics.
Modeling and Optimization of Methylene Blue Adsorption from Aqueous Solution by Pumice Based on RSM-CCD and ANN-GA Methods

Background: The discharge of a large volume of colored wastewater into receiving water sources has caused widespread concern around the world. The aim of this study was to investigate the efficiency of pumice as an adsorbent in removing methylene blue (MB) from aqueous solution. The adsorption process was also modeled and optimized by the methods as follows: central composite design-central composite design (RSM-CCD) and artificial neural network-genetic algorithm (ANN-GA). Methods and Materials: The independent variables in the study were included pH (3-11), contact time (10-50 minutes), adsorbent dose (0.1-2 g/L), and MB concentration (20-100 mg/l). The effect of these parameters on the efficiency of pumice in MB uptake was modeled and optimized by RSM-CCD and ANN-GA methods. A spectrophotometer at 620 nm was used to measure the residual MB concentration in solution. Results: The results showed that the RSM-CCD method has the ability to develop a quadratic polynomial model with high validity (R2 = 0.9997) for the adsorption process. Similarly, the ANN-GA method fitted well with experimental data to develop a model with high validity (R2 = 0.9978). The results of optimization process by RSM-CCD and ANN-GA methods obtained the highest adsorption efficiency at pH = 11, contact time = 50 minutes, adsorbent dose = 1 g/L, and concentration MB = 20 mg/L. Adsorption efficiency shows a direct relationship with pH, contact time and adsorbent dose and inversely with contaminant concentration. The linear effect of pollutant concentration and adsorbent dose variables had the greatest effect on adsorption efficiency. Conclusion: In this study, it was observed that pumice as a cheap and available adsorbent can be considered as a suitable choice for absorbing dye pollutants from aqueous media. RSM-CCD and ANN-GA methods can also be used to model and optimize adsorption processes.
Conductivity and Morphology Correlations of Ionic-Liquid/Lithium-Salt/Block Copolymer Nanostructured Hybrid Electrolytes

The most daunting challenge in solid-state polymer electrolyte membranes (PEMs) is to achieve high ionic conductivity close to that of the liquid electrolytes, while maintaining enhanced thermal and mechanical performances. The ionic conductivity in relation to the morphology of PEMs composed of diblock copolymer (polystyrene-block-poly(ethylene oxide); PS-b-PEO), lithium salt (lithium trifluoromethanesulfonate; LiTf), and ionic liquid (1-ethyl-3-methylimidazolium trifluoromethanesulfonate; EMIMTf) is investigated. The optimized functional nanostructured PEMs are achieved with room-temperature ionic conductivities higher than a 1 mS cm–1 benchmark. The morphology of these microphase-separated electrolytes is composed of a major soft high ionic-conductive PEO/LiTf/IL matrix with minor glassy high-modulus PS nanodomains. The ionic-liquid upload in hybrid electrolytes inhibits the PEO crystallization, reduces the PEO glass transition temperature, promotes an extended PEO chain conformation, and enhances the .
Le bi-partitionnement : Etat de l'art sur les approches et les algorithmes

Les methodes de bi-partitionnement cherchent simultanement des partitions sur l’ensemble des lignes et l’ensemble des colonnes. Ils trouvent aujourd’hui leur application dans plusieurs domaines tels que la bioinformatique, le text mining, le web mining. Dans ce papier, nous proposons une etude sur les approches et les algorithmes proposes pour le bi-partitionnement ainsi qu’une classification de ces algorithmes suivant le type des biclasses et les approches utilisees.
Detection of H alpha emission in a methane (T type) brown dwarf

We report the detection of H alpha emission in the T dwarf (methane brown dwarf) 2MASSW J1237392 + 652615 over three days using the Keek Low esolution Imaging Spectrograph. The measured line flux, log (L-H alpha/L-bol) = -4.3, is roughly consistent with early M dwarf activity levels and inconsistent with decreasing activity trends in late M and L dwarfs. Similar emission is not seen in two other T dwarfs.
Dynamic Memory Allocation Techniques for High-level Synthesis

Dynamic Memory Allocation Techniques for High-Level Synthesis Nicholas V. Giamblanco Master of Applied Science Graduate Department of Electrical and Computer Engineering University of Toronto 2020 The omission of support for several software-defined constructs within High-Level Synthesis (HLS) have hindered it’s broad adoption. Dynamic memory allocation is one feature that is not within the traditional supported subset. This works expands the synthesizable subset of the C languages for HLS tools, by including dynamic memory allocation algorithms (i.e. malloc and free). We define a variety of highlevel synthesis approaches to support malloc and free. We first provide a library of HLS-friendly allocation algorithms, libmem, which is studied for performance and area impacts. We also define a framework to improve the performance and area of dynamic memory allocation mechanisms in HLS applications. Our framework employs a variety of dynamic and static program analyses to identify the required size of the heap memory space, parallelize dynamic memory allocators and save precious on-chip BRAM. We evaluate our work with a variety of benchmarks, and demonstrate the usefulness of including dynamic memory allocation within HLS.
Self-Disclosure to a Robot: Only for Those Who Suffer the Most

Social robots may become an innovative means to improve the well-being of individuals. Earlier research showed that people easily self-disclose to a social robot even in cases where that was unintended by the designers. We report on an experiment of self-disclosing in a diary journal or to a social robot after negative mood induction. The off-the-shelf robot was complemented with our inhouse developed AI chatbot and could talk about ‘hot topics’ after having it trained with thousands of entries on a complaint website. We found that people who felt strong negativity after being exposed to shocking video footage benefited the most from talking to our robot rather than writing down their feelings. For people less affected by the treatment, a confidential robot chat or writing a journal page did not differ significantly. We discuss emotion theory in relation to robotics and possibilities for an application in design (the emoji-enriched ‘talking stress ball’). We also underline the importance of - otherwise disregarded - outliers in a data set that is of a therapeutic nature.
Current Progress of Magnetoresistance Sensors

Magnetoresistance (MR) is the variation of a material’s resistivity under the presence of external magnetic fields. Reading heads in hard disk drives (HDDs) are the most common applications of MR sensors. Since the discovery of giant magnetoresistance (GMR) in the 1980s and the application of GMR reading heads in the 1990s, the MR sensors lead to the rapid developments of the HDDs’ storage capacity. Nowadays, MR sensors are employed in magnetic storage, position sensing, current sensing, non-destructive monitoring, and biomedical sensing systems. MR sensors are used to transfer the variation of the target magnetic fields to other signals such as resistance change. This review illustrates the progress of developing nanoconstructed MR materials/structures. Meanwhile, it offers an overview of current trends regarding the applications of MR sensors. In addition, the challenges in designing/developing MR sensors with enhanced performance and cost-efficiency are discussed in this review.
Tailpipe emission characteristics of PM2.5 from selected on-road China III and China IV diesel vehicles

ABSTRACT Eighteen China III and IV diesel vehicles, including light-duty diesel trucks (LDDTs), medium-duty diesel trucks (MDDTs), heavy-duty diesel trucks (HDDTs) and buses, were tested with real-world measurements using a portable emission measurement system (PEMS). The emission factors (EFs), chemical components and surface morphology of emitted particles from these vehicles were characterized. Measured features included organic carbon (OC), elemental carbon (EC), water soluble ions (WSIs) and trace elements of PM2.5. The modelling system MOtor Vehicle Emission Simulator (MOVES) was also employed to estimate the PM2.5 EFs from these vehicles. Carbonaceous content made up 35.8–110.8% of PM2.5, the largest contribution of all the determined chemical components; WSIs and elements accounted for less than 10%. The average PM2.5 EFs of MDDTs and HDDTs were 0.389 g·km−1 and 0.115 g·km−1, respectively, approximately one order of magnitude higher than that of LDDTs. The PM2.5 EFs of China III buses were much lower than those of China III MDDTs and HDDTs, indicating that the inspection maintenance program (I/M) system was carried out effectively on public diesel vehicles. Moreover, the chemical composition of 9.2–56.2% of the PM2.5 mass emitted from China IV diesel trucks could not be identified in the present study. It was possible this unidentified mass was particle bound water, but this hypothesis should be confirmed with further measurements. The SEM images of PM2.5 samples presented a loose floc structure. In addition, the trends of variation of estimated PM2.5 EFs derived from the MOVES simulation were essentially consistent with those of tested values. Copyright © 2018 American Association for Aerosol Research
Effect of multi-walled carbon nanotubes on the physical properties and crystallisation of recycled PET/TPU composites

Thermoplastic polyurethane (TPU) was blended with recycled polyethylene terephthalate (rPET) to prepare rPET/thermoplastic polyurethane (TPU) composites. Meanwhile, multiple-walled carbon nanotubes (MWCNTs) were employed as a reinforcing filler to study the synergistic effect between CNTs and rPET/TPU composites. The effect of CNT content on the morphology and micro-structure of the composites was investigated using a scanning electron microscope (SEM) and X-ray diffraction (XRD). The thermal properties were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The mechanical properties were investigated using tensile tests and hardness measurements. The results showed that TPU was compatible with rPET. The existence of rPET changed the crystalline phase and affected the glass transition and crystallisation temperature of the TPU matrix. The rPET/TPU composites displayed poor thermal stability and tensile properties when compared to pure TPU. The addition of CNTs had no effect on the crystalline phase of the rPET/TPU composites. Due to the occurrence of interfacial adhesion between the CNTs and rPET, the CNTs displayed an offset effect on the reaction of rPET and decreased the rigidity of the molecular chain in the rPET/TPU composites. The thermal stability and tensile strength of the CNTs/rPET/TPU composites improved with an increase in CNT content.
Metabolic changes in non-alcoholic fatty liver disease : interactions with genes regulating fatty acid metabolism

The prevalence of overweight and obesity has increased globally, and more than 600 million adults are estimated to be obese. Obesity is closely associated with nonalcoholic fatty liver disease (NAFLD), with an estimated global prevalence of 25% based on imaging studies. Liver steatosis is defined as the presence of steatosis in >5% of hepatocytes. Non-alcoholic steatohepatitis (NASH) is diagnosed when there is histological evidence of inflammation and ballooning in addition to steatosis, with or without fibrosis. NAFLD is associated with increased mortality and a higher prevalence of hypertension, type 2 diabetes, increased insulin resistance, hypertriglyceridemia, and lower high-density lipoprotein levels. The key feature of NAFLD is the accumulation of triglycerides into hepatocytes, and the pathogenesis of NAFLD is associated with several disturbances in fatty acid metabolism, modified by lifestyle factors and genetic variation. In this doctoral thesis we aimed to study the role of fatty acid metabolism and expression of genes participating in fatty acid metabolism in NAFLD. Moreover, we wanted to study the effects of bariatric surgery on fatty acid metabolism. The primary study population of this thesis consisted of subjects from the Kuopio Obesity Surgery Study (KOBS). We demonstrated several alterations in fatty acid metabolism and endogenous desaturase activities that associate with NASH, independently of obesity and diet (n=92 from KOBS). Obese individuals with NASH had higher estimated activities of delta-6 desaturase and stearoyl-CoA desaturase 1, and lower activity of delta-5 desaturase than individuals with a normal liver. Moreover, NASH was associated with higher hepatic mRNA expression of FADS1, FADS2, and SCD. Finally, some of the differences in fatty acid metabolism that associated with NASH in obese individuals, were also observed in individuals with high alanine aminotransferase in
IPv6 Addresses as Content Names in Information-Centric Networking

Content is quickly beginning to emerge as the core of Internet and networking applications today. Among the most important research issues with content is the problem of addressing and naming content, since a robust and naming-centric networking strategy will enable the building of next-generation Internet architectures that can easily scale content demands correctly. We propose a counter-intuitive approach to solving the naming problem, by using IPv6 addresses as content names. We explain our proposal and architecture for using IPv6 addresses for content names, and argue that using IPv6 addresses for naming content will allow us to solve the problems of routing and directory services associated with naming.
Does the Choice of Spot, Morning or Both Sputum Samples Determine Optimal Performance Of a TB Diagnostic Tool?

INTRODUCTION Spot and morning sputum samples are used in the diagnosis of Pulmonary Tuberculosis (TB). There are no guidelines currently for a choice of two sputum samples to be used in determining optimal performance of a diagnostic tool. Performance has been determined using one of the four approaches of choice of sputum samples in different studies with varying results. The choices include; (a) Final diagnosis based on both spot and morning sample results, whereby the patient is the unit of analysis (point-of-care) [1,3] (b) Spot sample results (c) Morning sample results [1] (d) Pooled results of spot and morning samples [3]
SPECTROSCOPIC EVALUATION OF ACTIVATED CHARCOAL AS A POISON ANTIDOTE FOR GLICLAZIDE DRUG

Â Objective: The aim of the present study is to evaluate the ability of activated charcoal in adsorbing overdosage of gliclazide drug, and to study the effects of pH, concentration and time on this process.Methods: To evaluate the effect of pH, concentration and time; 50 ml of the drug solution (100 mg/L) were allowed to stand with the activated charcoal for 1 h at pH of 1.5, 4, 7, and 9 for pH study. 50 ml of the drug solution concentrations of 25, 50, 75, and 100 (mg/L) were allowed to stand with 1 g activated charcoal for 1 h for concentration study. 50 mg of the drug solution (100 mg/L) were allowed to stand with the activated charcoal for 15, 30, 45, and 60 min for time study. The concentrations of the adsorbed drug were determined spectrophotometrically.Results: The adsorption of the gliclazide drug on activated charcoal was found to be pH, concentration, and time-dependent. The amounts of the drug adsorbed were 3, 0.75, 0.6, and 0.5 mg/g for pHs 1.5, 4, 7, and 9, respectively, for pH study. For concentration study, the amounts adsorbed were 0.15, 0.22, 0.33, and 0.58 mg/g for concentrations 25, 50, 75, and 100 mg/L, respectively. For time study, the amounts were 0.3, 0.4, 0.51, and 0.65 mg/g for reaction times 15, 30, 45, and 60 min, respectively.Conclusion: The best adsorption circumstances of gliclazide drug on activated charcoal that were found; acidic pH, a high concentration of the drug and longtime of contact.
Insights into the Stability of Zeolitic Imidazolate Frameworks in Humid Acidic Environments from First-Principles Calculations

Understanding the degradation mechanisms of zeolitic imidazolate frameworks (ZIFs) is crucial to improve their chemical stability and realize their potential industrial applications. Here, we conduct a comprehensive study utilizing dispersion-corrected density functional theory calculations to investigate the chemical stability of bulk ZIFs and their external surfaces under conditions of acid-gas exposure. We examine the influence of steric factors such as topology and ligand functionalization on the relative chemical stability of prototypical ZIFs (ZIF-2 and ZIF-8), including their hypothetical polymorphs. We find that defect formation is more thermodynamically and kinetically favorable at ZIF external surfaces versus the bulk, and that both topology and ligand functionalization impact defect formation. In addition, we provide a detailed mechanism for the reaction of ZIFs with sulfurous and sulfuric acids, of which the latter serves as a catalyst in potential degradation reactions of ZIFs. We also provid.
Using mixtures of stearic acid and beta-sitosterol to solidify vegetable oils by introducing oleogels

OF THE DISSERTATION . ii Acknowledgement . v Table of Content . vii List of Tables . xii List of Figures . xiii Abbreviation . xxi 1. Research Background . 1 2. Literature review . 8 2.1. Gels . 8 2.1. 1. What is a gel? 8 2.1. 2. Classification of gels . 9 2.2. Molecular gels . 10 2.2.1. Definition . 10 2.2.2. Mechanism of molecular gel formation . 11 2.2. 3. An important factor in molecular gel formation -­‐ Solvents . 12 2.2. 4. Another key factor in molecular gel formation -­‐ Gelators . 15 2.2. 5. Applications . 16 2.2. 5.1. Delivery vehicle with controlled release . 16
Modellierung von Reaktion und Stofftransport in geformten Katalysatoren am Beispiel der Methanolsynthese

Der Einfluss der Katalysatorformgebung auf die Effektivkinetik der Methanolsynthese an kupferbasierten Katalysatoren wurde im Rahmen dieser Arbeit untersucht. Das Dusty-Gas-Modell als mechanistischer Ansatz zur Beschreibung des Stofftransportes in porosen Medien wurde hierzu gemeinsam mit einer mikrokinetischen Beschreibung der Methanolsynthese ausgehend von Langmuir-Hinshelwood Ansatzen in einem Katalysatorformkorpermodell implementiert. Zur Parametrisierung und Validierung der entwickelten Modelle wurden in einem parallelisierten Rohrreaktorsystem Experimente zur Mikrokinetik sowie in einem Differential-Kreislaufreaktor Experimente zur Makrokinetik durchgefuhrt. Das entwickelte Formkorpermodell des Katalysators erlaubt eine quantitative Beschreibung des Einflusses der Formgebung auf die Effektivkinetik von Methanolsynthese-Katalysatoren und unterstutzt somit die wissensbasierte Katalysatorentwicklung.
Revisiting the Chrome Azurol S Assay for Various Metal Ions

Siderophores play an important role in the solubilisation and mobilization of iron (III) and various metal ions. To have a useful method to test siderophores in culture supernatants for their metal binding affinity, we redesigned and optimized the liquid CAS-assay for selected metal ions. CAS-assay solutions were calibrated with desferrioxamine B in different concentrations to calculate DFOB-equivalents to get a semi-quantitative evaluation. With these assay solutions, we were able to test siderophores in culture supernatants for their ability to chelate with Fe, Al, Ga, Cu, V and As.