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Item Restricted Synthesis of Organoselenium Compounds via flow Electrochemistry(Cardiff University, 2024) Alzaidi, Ohud; Wirth,ThomasRecently, Chemists have become interested in electroorganic chemistry because of its effectiveness and capacity to create organic compounds by introducing or withdrawing electrons. Furthermore, flow platforms are effectively used to provide practical solutions for the prevalent disadvantages of batch electrolysis. In this work, the focus will be on contributions of electroorganic synthesis especially of organselenium coumpounds, which have gained interest, recently, as reagents and catalysts due to their applications in medicinal and material sciences. Furthermore, another area of interest is the use of heterocyclic compounds containing selenium in organic conductors. The contributions of electroorganic synthesis to environmentally friendly chemistry will be the main focus of this work. In the first part of this work, the synthesis of novel non-racemic triazole-containing diselenides (Scheme i) was attempted via several routes. Chiral triazole-containing diselenides could not be synthesised with these concepts and further efforts would be required to achieve the synthesis and to attempt asymmetric selenenylations subsequently.A straightforward and effective electrochemical flow process has been developed for the α- selenylation of 1,3-dicarbonyl compounds (Scheme ii) using a simple commercially available electrochemical flow cell (the Ion reactor). The main aim of this part is to develop an electrochemical methodology for the synthesis of α-selenyl derivatives of 1,3-dicarbonyl compounds and benefit from continuous flow electrochemical technology to efficiently access such highly valuable reagents that can be used in a wide range of chemical syntheses.Finally, for the electrochemical selenocyclization of N-allyl benzamides and unsaturated oximes to selenofunctionalized oxazolines and isoxazolines, respectively, a simple and effective continuous flow electrochemical method is established. Using a straightforward, widely accessible electrochemical flow cell (the Ion reactor), this process gives good yields of selenofunctionalized oxazolines and isoxazolines while working well with a wide variety of substrates (Scheme iii).18 0Item Restricted Microwave Assisted Synthesis of Au/TiO2 Catalyst for Photocatalysis and Oxidation Processes(Cardiff University, 2024) Alazmi, Abdullah Mubarak S; Edwards, JenniferHeterogeneous catalysis using supported metal nanoparticles has attracted tremendous interest for applications including photocatalysis and selective oxidations. This work focuses on synthesis and characterization of Au nanoparticles supported on TiO2 (Au/TiO2), which exhibits unique photocatalytic and catalytic properties arising from quantum and plasmonic effects of Au as well as strong metal-support interactions. A facile microwave-assisted polyol approach was used to prepare Au/TiO2 with 0.1-3 wt% Au loading. Structural characterization by XRD revealed anatase TiO2 support was retained after Au deposition. Au particle size increased from sub nm clusters at 0.1 wt% to 13.5 nm nanoparticles at 3 wt% loading, demonstrating tunable nanoparticle dimensions. CO oxidation testing showed highest mass activity for 0.5 wt% Au/TiO2, with declining performance at higher loadings attributed to loss of low-coordination sites through agglomeration. Photocatalytic degradation of methyl orange dye was most efficient with 0.5 wt% Au/TiO2 under simulated solar irradiation. The higher photoactivity is ascribed to improved visible light harvesting and minimized charge recombination from uniform deposition of small plasmonic Au nanoparticles. The results demonstrate optimized Au loading and dispersion governs both catalytic and photocatalytic efficiency of Au/TiO2 synthesized via microwave polyol method.33 0Item Restricted Polymers for Energy‐efficient Membrane Separations(University of Manchester, 2024) Aloraini, Sulaiman Ibrahim S; Budd, Peter MAdvanced membrane materials have come under increased scrutiny due to the growing need for environmentally friendly and economically viable gas and organic solvent separation processes. Among them, Polymers of Intrinsic Microporosity (PIMs) are particularly noteworthy because of their high free volume and remarkable permeability, which make them ideal candidates for separation processes. However, despite their outstanding permeability and selectivity, long-term stability issues, particularly under harsh conditions and physical aging, have hindered their widespread adoption. This research seeks to address these challenges by investigating innovative approaches to enhance the performance and durability of membranes based on the prototypical PIM, referred to as PIM-1. A variety of modification options are investigated in this work with the goal of improving PIM-1 membrane stability and overall separation efficiency. These tactics include crosslinking PIM-1 with palladium acetate, functionalising PIM-1 with diethanolamine (DEA), and blending with polyethyleneimine (PEI) to enhance stability in organic solvents. The crosslinking process, in particular, leads to significant improvements in mechanical properties and solvent resistance, making the membranes more suitable for applications such as pervaporation of organic-organic mixtures and phenol removal via perstraction. The use of these modified PIM-1 membranes in pervaporation is exemplified by the separation of toluene from dimethyl sulfoxide mixtures. Crosslinked PIM-1 membranes demonstrated increased flux throughout the separation process, markedly surpassing conventional membranes. Furthermore, the functionalisation of PIM-1 with DEA enhanced selectivity, especially in the separation of methanol from organic solvents. The process of perstraction demonstrates the efficacy of PIM-1 membranes in extracting phenol from aqueous solutions, underscoring the benefits of crosslinking, which result in improved selectivity and stability during prolonged operation. This research not only enhances comprehension of PIM-1-based membrane modifications but also provides practical insights into their industrial applications, thereby facilitating the development of more efficient separation technologies for challenging solvent environments.9 0Item Restricted Hydrochemical assessment of an urban groundwater-fed wetland at Sweet Briar Marsh(University of East Anglia, 2024) BinTani, Sharifah Ahmed; Hiscock, Kevinتتعمق هذه الأطروحة بعمق في النظام البيئي المعقد لمستنقع سويت براير، بهدف فهم العوامل العديدة التي تؤثر على جودة المياه. ستكشف الأطروحة عن التفاعلات والتأثيرات المعقدة التي تشكل التوازن الدقيق للمستنقعات من خلال فحص شامل لدرجة الحموضة والأكسجين المذاب والتوصيل ودرجة الحرارة ومستويات المغذيات. يسلط التحقيق الضوء على أن الجريان الزراعي والتوسع الحضري والأنشطة الصناعية تلعب دورًا مهمًا في رفع مستويات النترات والفوسفات، ويرجع ذلك أساسًا إلى الاستخدام المكثف للأسمدة وممارسات إدارة الثروة الحيوانية غير الكافية. تؤدي مستويات المغذيات المرتفعة هذه إلى تلوث المغذيات، مما يزيد من خطر التغذية الزائدة، حيث تحفز المغذيات الزائدة ازدهار الطحالب الضارة وتدهور جودة المياه. تم اقتراح استراتيجيات مختلفة لإدارة المياه لمكافحة هذه التحديات الملحة، بما في ذلك إدارة المغذيات الدقيقة وتدابير مكافحة التلوث. وتؤكد الدراسة على الحاجة الماسة إلى خطط إدارة مصممة خصيصًا والرصد المستمر لحماية الأراضي الرطبة. ويساهم هذا البحث في المعرفة الأوسع بممارسات إدارة الأراضي الرطبة الفعّالة من خلال توفير رؤى متعمقة من الملاحظات الميدانية، مع التأكيد على أهمية مواجهة قضايا جودة المياه المحلية.21 0Item Restricted Quantitation of Taxifolin and its Related Metabolites in Bark Extract by UPLC-MS/MS(University of Edinburgh, 2024) AlIbrahim, Fatimah; Clarke, DavidDrug resistance poses a rising problem for the control of helminth infections in animals, and recently research efforts have highlighted secondary plant metabolites, such as flavonoids, as promising compounds with anti-parasitic activity.1-4 However, accurately quantifying metabolites in complex plant matrices remains challenging. This project addresses this challenge by developing a sensitive analytical method to quantify three flavonoids; taxifolin, quercetin, and luteolin in bark extracts using ultra high-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The three analytes were separated on a BEH C18 column (2.1mm ×100mm × 1.7µm) using a gradient elution with a mobile phase of water and acetonitrile in 0.1% formic acid. Ion pair monitoring in negative ESI mode using the SRM method was successfully developed for each metabolite. The calibration curve of taxifolin demonstrated excellent linearity over the concentration range of 2-50 µM with a correlation coefficient of 0.99949. Quercetin and luteolin did not demonstrate reliable calibration curves nor were they detected in any bark extracts. Taxifolin was analysed in ten bark samples and four samples were above the level of quantitation. In future work, the quantitation of secondary metabolites in bark samples will be correlated to biological activity to identify possible cost-effective natural anti-parasitic additives for animal feed.13 0Item Restricted Probing Metabolic Pathways using an RccR Based Genetically Encoded Biosensor(Saudi Digital Library, 2023-11-24) Babtain, Ahmad; Dixon, NeilThe study of metabolic pathways is of utmost importance to contemporary biotechnology. However, mapping metabolic pathways is a burdensome process due to the entangled and complex nature of biological systems. Due to the direct involvement of transcription factors in metabolism, biosensors based on them are a powerful tool for researching metabolism. In this study, we used a biosensor vector where the RccR transcription factor regulates the expression of eGFP in response to the metabolite KDPG to investigate the central metabolism of two bacterial species of high relevancy to biotechnology: Pseudomonas Putida and Escherichia Coli, with an experimental focus on the first. Our research demonstrates that acetate, aromatic acids, and fatty acids enter the central metabolism of P. Putida through the TCA cycle. We also show among the aromatic acid, PCA and benzoic acid flux into central metabolism through one metabolic intermediate through a pathway with moderately low metabolic leakage. On E. Coli’s end, we show that acetate and the fatty acid C18:2 enter metabolism through the TCA cycle as well. We also employ bioinformatic databases to show that HexR is closely related to RccR and that the differences between the HexR proteins in P. Putida and E. Coli might show differing interference with RccR’s function. Our results also indicate that P. Putida preferentially consumes glucose, then acetate, and then aromatic acids when presented with mixtures of them. Finally, we saw strong evidence of the presence of a metabolic pathway that leads from acetate into the central metabolism of E. Coli. through acetyl-CoA.27 0