Use of piperazine ligands for bleaching and epoxidation catalysis

PhDFollowing reports that the dinuclear manganese complex of the ligand 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane (TMTACN) was a potent bleaching catalyst, its catalytic oxidative activity was thoroughly studied. Apart from its catalytic bleaching activity, it has shown to be a versatile catalyst in terms of its substrate scope. In bleaching, it still remains the benchmark with regards to its catalytic bleaching activity against which systems in development are compared. Chapter one discusses the need for a bleaching catalyst in detergent formulations and the advantages it offers over existing technologies. Studies into the bleaching mechanism involving the manganese TMTACN system are then explored, followed by a description of its application in the oxidation of alkenes amongst other substrates. Other manganese based bleaching and epoxidation catalysts are considered briefly. This is followed by a discussion on ligand design for use in manganese and other first row transition metal based oxidation catalysts and the initially proposed ligand synthesis for this research. Chapter two details the synthetic strategies employed in the synthesis of the planned ligands along with an evaluation of the effectiveness of these strategies. The structural features of a number of novel ligands and their precursors are then explored in terms of their single crystal X-ray structures which were obtained during this research. Chapter three presents the most relevant results obtained during the course of this research with regards to the testing of the synthesised ligands and their efficacy in bleaching and epoxidation catalysis. A number of ligands demonstrated some activity in epoxidation catalysis using different manganese salts. These results are discussed in detail with an attempt to rationalise the observed catalytic activity with reference to the ligand structure and identity of the manganese salt utilised being made. The final chapter provides the necessary details of the experimental work carried out along with supporting characterisation data for the materials prepared.Engineering and Physical Science Research Council (EPSRC) Warwick international Lt

An investigation into distribution parameters of steam turbine blade and wheel vibration measurements

This investigation was carried out to find a concise and meaningful way of describing the steam turbine blade and wheel vibration measurements which would enable predictions from "experimental" to "production" wheels to be made with known level of confidence. A large volume of vibration measurements from many years of testing was available. For the purpose of this study it was decided to concentrate the analysis on stage six of low-pressure turbine wheels. Two types of wheels, similar in every respect except root fixation, were used. The method of obtaining and interpreting static and dynamic blade and wheel vibration frequency measurements is described. Measurements from the wheels selected for study were analysed by appropriate statistical techniques to test assumptions and hypotheses derived from long-standing experience of empirical vibration tests. It was found that statistical analysis yields results in line with engineering expectations. In specific instances relating to the use of "experimental" wheels in predicting the performance of "production" wheels the statistical analysis not only confirmed existing practice, but pointed towards a more precise foundation of the procedure of estimating dynamic frequencies for production wheels. The suitability of the use of statistical techniques for analysis of problems of this kind is discussed

Cities within a city : planning policies and intra-urban inequalities in Greater Sydney

Numerous research papers and reports have acknowledged Sydney’s inequalities in terms of place-based difficulties, governance, migrant settlement, displacement, gentrification, housing development, and affordability. However, that research is not specific to the urban inequalities related to urban policy applications. Considering the gap, this research investigates the urban planning practices, their impacts and outcomes in Sydney in light of case studies, secondary evidence, empirical data and critical urban philosophies. The key questions in this research are: how is Sydney transforming into an increasingly unequal city? how do influential socio-economic actors contribute to urban inequalities? what is the situation of the rights to the city in the disadvantaged geographies of Sydney? And how are the life and livelihoods of Sydney’s underprivileged residents disproportionately affected by the COVID-19 pandemic? This research employs critical theory as a crucial lens to analyse the socio-economic disparities in urban spaces. The critical analysis outlines that the NSW urban planning system, practices and outcomes influence the cities within a city divide in Sydney, supporting secondary content and empirical data. The affluent areas are prioritised in neoliberal urban growth with less housing and population targets and expanded opportunities. In contrast, the disadvantaged regions have extreme urbanisation instead of much needed urban opportunities and infrastructure support. The NSW urban planning practices are strongly influenced by socio-economic power; consequently, high socio-economics northern and eastern areas of Sydney influence the urban growth and development. They are able to prevent densification in their areas. On the other hand, the less affluent residents of low socio-economic Western Sydney areas lack the power to resist large volumes of additional dwellings leading to fast densification. The critical analysis of this research outlines Sydney’s urban policy practices, planning powers, and urban rights divide as an ‘east–west divide’. This research points out that empowered local politics, expanded communication, enhanced consultation, and improved community engagement mechanisms are needed to effectively engage Western Sydney residents in the planning process. This research develops the ‘Equal, Resilient and Sustainable Western Sydney Model’ to address the existing urban divide and build equal, sustainable and resilient cities and communities. This thesis also proposes numerous strategies to ensure Western Sydney residents’ active and robust community engagement. In addition, better and accessible education, improved human resources, innovation, technological transformation, and efficient infrastructure are vital to enhancing socio-economic development in disadvantaged Western Sydney

Superficial Parotidectomy by Retrograde approach through Marginal Mandibular Nerve Dissection

Background: Parotid gland is most commonly involved in tumors, comprising about 80% of the salivary gland neoplasms. Majority of parotid tumors are benign in nature, the most common being pleomorphic adenoma. Superficial Parotidectomy is the preferred treatment option, using either anterograde or retrograde approach. The objective of this study was to determine the post-operative facial nerve status and other complications following superficial Parotidectomy by retrograde dissection for benign lesions of parotid gland.Material and Methods: This prospective clinical study included a total of 22 patients who had superficial Parotidectomy by retrograde technique involving marginal mandibular nerve dissection. These patients were studied post-operatively for facial nerve status, Frey’s Syndrome, wound infection and salivary fistula.Results: Out of a total of 22 patients, 54.54% developed temporary facial palsy on ipsilateral angle of mouth and all of them recovered by the end of 3 months post-surgery. Two patients (9.09%) developed salivary gland fistula and both of them healed spontaneously within two weeks. Frey’s Syndrome and wound infection were not seen in any of the patients included in the study. Histopathology of these lesions revealed pleomorphic adenoma (n=20) and Warthin’s tumor (n=2), respectively.Conclusion: The use of marginal mandibular nerve as a landmark for retrograde dissection of facial nerve in superficial Parotidectomy is a reliable method to ensure lower percentage of facial nerve injury and associated complications

Management of broken instrument by file bypass technique

Different devices and techniques have been developed to retrieve fractured instruments during the endodontic procedures. This case report describes the management of a broken instrument, which was accidentally broken during cleaning and shaping of the root canal in right 2nd molar tooth. A # 25 stainless steel K-file was separated in mesiobuccal canal of the treated tooth. At first, a radiograph was taken to confirm the level of separation of the instrument. The instrument was found to be separated at the apical 3rd of the mesial canal and then file bypass technique was performed. Calcium hydroxide dressing was given for 7 days followed by obturation with guttapercha cone and zinc oxide eugenol sealer in lateral condensation technique. It can be concluded that bypass technique can be considered as simple and effective technique for the management of broken instrument into the root canal

On-chip Voltage Regulator– Circuit Design and Automation

Title from PDF of title page viewed May 24, 2021Dissertation advisors: Masud H Chowdhury and Yugyung LeeVitaIncludes bibliographical references (page 106-121)Thesis (Ph.D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2021With the increase of density and complexity of high-performance integrated circuits and systems, including many-core chips and system-on-chip (SoC), it is becoming difficult to meet the power delivery and regulation requirements with off-chip regulators. The off-chip regulators become a less attractive choice because of the higher overheads and complexity imposed by the additional wires, pins, and pads. The increased I2R loss makes it challenging to maintain the integrity of different voltage domains under a lower supply voltage environment in the smaller technology nodes. Fully integrated on-chip voltage regulators have proven to be an effective solution to mitigate power delivery and integrity issues. Two types of regulators are considered as most promising for on-chip implementation: (i) the low-drop-out (LDO) regulator and (ii) the switched-capacitor (SC)regulator. The first part of our research mainly focused on the LDO regulator. Inspired by the recent surge of interest for cap-less voltage regulators, we presented two fully on-chip external capacitor-less low-dropout voltage regulator design. The second part of this proposal explores the complexity of designing each block of the regulator/analog circuit and proposed a design methodology for analog circuit synthesis using simulation and learning-based approach. As the complexity is increasing day-by-day in an analog circuit, hierarchical flow mostly uses for design automation. In this work, we focused mainly on Circuit-level, one of the significant steps in the flow. We presented a novel, efficient circuit synthesis flow based on simulation and learning-based optimization methods. The proposed methodology has two phases: the learning phase and the evaluation phase. Random forest, a supervised learning is used to reduce the sample points in the design space and iteration number during the learning phase. Additionally, symmetric constraints are used further to reduce the iteration number during the sizing process. We introduced a three-step circuit synthesis flow to automate the analog circuit design. We used H-spice as a simulation tool during the evaluation phase of the proposed methodology. The three most common analog circuits are chosen: single-stage differential amplifier, operational transconductance amplifier, and two-stage differential amplifier to verify the algorithm. The tool is developed in Python, and the technology we used is0.6um. We also verified the optimized result in Cadence Virtuoso.Introduction -- On-chip power delivery system -- Fundamentals of on-chip voltage regulator -- LDO design in 45NM technology -- LDO design in technology -- Analog design automation -- Proposed analog design methodology -- Energy efficient FDSOI and FINFET based power gating circuit using data retention transistor -- Conclusion and future wor

Neoliberalism, power, and right to the city and the urban divide in Sydney, Australia

Sydney, the capital of the Australian state of New South Wales, is geographically divided by socio-economic conditions and urban opportunities. However, the division in Sydney has not been investigated from an urban planning perspective. This research hypothesises that the urban planning system and its practice-produced consequences promote inequalities in Sydney. This study conceptualises Sydney’s urban inequality in the context of critical concepts of neoliberalism, the theory of power, and the right to the city. Based on semi-structured interviews, secondary documents, and data analysis, this research claims that residents of lower socio-economic areas lag behind compared to others. The paper emphasises the significance of a just city and strong community engagement to reduce the disparate urban policy practices that influence urban divides in Sydney

Molecular dynamics simulation on surface modification of a quantum scaled CuO nano-clusters to support their experimental studies

© 2022 Springer Nature Limited. This article is licensed under a Creative Commons Attribution 4.0 International License, to view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Interest in nanoparticle modification using functional chemicals has increased rapidly, as it is allowing more freedom of physiochemical tuning of the nanoparticle’s surfaces into biomedically oriented and designated properties. However, the observation and detection of the thin molecular layers on the nanoparticle surface are very challenging under current analytical facilities. The focus of this research is to demonstrate fundamental interactions between the surface treated nanoparticles and their host liquid media using lab-based experimentation and simulation. In this research, investigation has been carried out on analyzing the surface compatibility and the diffusivity of modified CuO nanoparticles with short-chain carboxylate-terminated molecules in biofluids. Moreover, during the current Covid-19 pandemic, the Cu/CuONPs have proved effective in killing SARS-CoV1/2 and other airborne viruses. This research was conducted at the molecular level with joint consideration of experimental and simulation studies for characterization of variables. Experimental tests conducted using Fourier Transmission Infrared (FTIR) demonstrated several ranges of interest from FTIR responses, specifically, detection of three major carboxylate attachments (i.e., 1667 cm-1 -1609 cm-1, 1668 cm-1 - 1557 cm-1, etc.) were found. From simulation, similar attachment styles were observed by the LAMMPS simulation package that mimicked similar agglomerations with a predicted diffusion coefficient as recorded to be 2.28E-9m2/s. Viscosities of modified nanofluids were also compared with unmodified nanofluids for defining aggregation kinetics.Peer reviewe