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2. Innovative coatings for electrical steel

Author

Edwards, Lee

Abstract

Grain oriented electrical steel is a specialist steel used in the laminations of electricity transformer cores. The steel has a surface tension coating applied that is both insulating and reduces magnetostriction. The latter is responsible for the humming heard from transformers and can account for up to 10-15% power losses from the transformer. Motivated by the regulatory need to remove chromium chemistry from technological applications, this thesis addresses the topic of chromium species in tension coatings for grain oriented electrical steel. More specifically, the initial goal was to characterise the structure and chemistry of Cr-doped aluminium phosphate used for such coatings in order to elucidate key performance indicators. This enabling knowledge was evaluated and employed for formulating new Cr-free coatings, with performance exceeding that of their Cr-doped predecessors. Aluminium phosphates are used in tension coatings for Electrical Steel. 1, 2.5 and 3% Cr-doped aluminium phosphates were investigated for their superiority over the non-doped equivalent and fully characterised. TGA and DSC gave details of the reaction mechanism and showed that doping Al(PO3)3 with Cr promotes the phosphate polymerisation reaction. The initial ortho-pyro-phosphate step temperature was reduced by ~ 170oC and the total curing temperature by more than 230oC. Samples were prepared at 500 and 800oC. SCXRD showed that Al and Cr share sites and have octahedral geometry. They are linked with cyclic phosphates. XANES confirmed Cr geometry and gives a Cr oxidation of CrVI with a shift in edge energy from 5989 eV for Cr metal to 6008 eV for the Cr-doped materials. XPS gave a Cr(2p) binding energy of 578.78 eV which confirms the presence of surface CrIII. XRD showed that all samples were a single-phase cubic structure when cured to 800oC. At 500oC there is a mixture of monoclinic and cubic structure with an increase in ratio of cubic over monoclinic with increased Cr %. DRS-UV showed the presence of some octahedral CrIII. Octahedral CrVI d0 would be UV silent. There are no other Cr oxidation states present. TGA showed 2.5% Cr/Al(H2PO4)3 gave the optimum full curing to Cr/Al(PO3)3. The non-doped Al(PO3)3 never fully cures. ii This new knowledge led directly to a novel tension coating formulation using Al(NO3)3.9H2O as a precursor that mimics chromium doped coatings characteristics without using toxic chromates. Separately, carbon doping of aluminium phosphate tension coatings was investigated to determine if its addition improved magnetic performance. Separate and successful pilot trials were performed on both the novel Al(NO3)3.9H2O and carbon doped tension coating formulations, with patents pending. There are exciting possibilities for these coatings and also for future work.

Published
2021

6. Photoinduced Alkylation of Diazines with N -(Acyloxy)phthalimides in the Presence of Triethylamine.

Author

Guerrero, Itziar, Tan, Eugene Yew Kun, Liu, Yuliang, Edwards, Lee J., and Chiba, Shunsuke

Subjects
COUPLING reactions (Chemistry), PHTHALIMIDES, DIAZINES, RADICALS (Chemistry), ALKYLATION
Abstract

A photochemical protocol for the alkylation of diazines (pyrimidines, pyrazines, and pyridazines) with N -(acyloxy)phthalimides has been developed. The process is facilitated by the presence of triethylamine under irradiation with 427–390 nm light; this enables rapid cross-coupling reactions to construct a wide range of alkylated diazines. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Deville rebooted – practical N2O5 synthesis.

Author

Edwards, Lee E., Kariuki, Benson M., Didsbury, Matthew, Jones, Christopher D., and Wirth, Thomas

Subjects
*SILVER chloride, *NITRIC acid, *PHOTOCATALYSIS, *CHLORINE
Abstract

Dinitrogen pentoxide (N2O5), the anhydride of nitric acid, was synthesised by Henri E´tienne Sainte-Claire Deville in Paris in 1849 using silver nitrate and chlorine gas. Herein, we revisit, optimise, and modify Deville’s method using photocatalysis to enable a safe, clean, practical, and reproducible alternative for N2O5 synthesis in quantitative yields. Moreover, it is predicted that the modifications can accommodate an industrial scale-up, but the silver chloride generated must be recycled. [ABSTRACT FROM AUTHOR]

Published
2024
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16. High-frequency flow reversal of AC electro-osmosis due to steric effects

Author

Storey, Brian D., Edwards, Lee R., Kilic, Mustafa Sabri, and Bazant, Martin Z.

Subjects
Condensed Matter - Other Condensed Matter
Abstract

The current theory of alternating-current electro-osmosis (ACEO) is unable to explain the experimentally observed flow reversal of planar ACEO pumps at high frequency (above the peak, typically 10-100 kHz), low salt concentration (1-1000 $\mu$M), and moderate voltage (2-6 V), even if taking into account Faradaic surface reactions, nonlinear double-layer capacitance and bulk electrothermal flows. We attribute this failure to the breakdown of the classical Poisson-Boltzmann model of the diffuse double layer, which assumes a dilute solution of point-like ions. In spite of low bulk salt concentration, the large voltage induced across the double layer leads to crowding of the ions and a related decrease in surface capacitance. Using several mean-field models for finite-sized ions, we show that steric effects generally lead to high frequency flow reversal of ACEO pumps, similar to experiments. For quantitative agreement, however, an unrealistically large effective ion size (several nm) must be used, which we attribute to neglected correlation effects., Comment: 12 pages

Published
2007

20. Introduction

Author

Somerville, Ian, primary, Edwards, Lee, additional, and Ihlen, Øyvind, additional

Published
2019
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23. Public relations recruitment as boundary-making: The client, the ‘fit’ and the disposability of diversity

Author

Edwards, Lee and Aulakh, Sundeep

Abstract

In this article we explore the ways in which specialist recruitment practices for the PR industry influence the pursuit of diversity in the profession. Drawing on interviews from an exploratory study of specialist PR recruitment in the UK, we combine Abbott’s theory of boundary-making between professional fields with existing research on the exclusionary dynamics of recruitment in professions, to explain how PR recruitment consolidates the focus on client and candidate ‘fit,’ and is likely to work in favour of preserving the dominance of middle-class, white and gendered identities in the profession. In this context, diversity is perceived as a risk rather than an opportunity and becomes a casualty of professional logic.

Published
2024
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26. Media Literacy in the Time of Covid

Author

McDougall, Julian, Edwards, Lee, and Fowler-Watt, Karen

Abstract

In the early stages of the pandemic, U.N. Secretary-General Antonio Guterres warned that the world was not only fighting coronavirus “but our enemy is also the growing surge of misinformation”. (Associated Press, 28.3.20). \ud Media literacy in the time of Covid is situated at an intersection between its value as an educational innoculation against misinformation in general and the urgency of a rapid response to misinformation about the virus. Media literacy in this context takes on a role in public health. \ud This article reviews the evidence for the effectiveness of media literacy in both contexts, collating findings from reviews conducted for the UK Department for Culture, Media and Sport (DCMS), European Commisssion, US Embassy and UK Office of Communications (OFCOM), together with a rapid evidence analysis of media literacy with an applied, specific focus on ‘Covid fake news’.

Published
2021
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29. Conservatism's Unsung Hero

Author

Edwards, Lee

Subjects
M. Stanton Evans: Conservative Wit, Apostle of Freedom (Biography) -- Hayward, Steven F., Books -- Book reviews, Political science
Abstract

M. Stanton Evans: Conservative Wit, Apostle of Freedom, by Steven F. Hayward (Encounter Books, 400 pp., $33.99) Who wrote the Sharon Statement, the conservative movement's most enduring statement of principle? [...]

Published
2022

30. Nanoscale characterization of plasma functionalized graphitic flakes using tip-enhanced Raman spectroscopy.

Author

Kumar, Naresh, Marchesini, Sofia, Howe, Thomas, Edwards, Lee, Brennan, Barry, and Pollard, Andrew J.

Subjects
RAMAN spectroscopy, X-ray photoelectron spectroscopy, ANALYTICAL chemistry, TIME-of-flight spectroscopy, MATERIALS, SECONDARY ion mass spectrometry
Abstract

The chemical functionalization of graphene nanomaterials allows for the enhancement of their properties for novel functional applications. However, a better understanding of the functionalization process by determining the amount and location of functional groups within individual graphene nanoplatelets remains challenging. In this work, we demonstrate the capability of tip-enhanced Raman spectroscopy (TERS) to investigate the degree and spatial variability of the appearance of disorder in graphitic nanomaterials on the nanoscale with three different levels of nitrogen functionalization. TERS results are in excellent agreement with those of confocal Raman spectroscopy and chemical analysis, determined using x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry, of the functionalized materials. This work paves the way for a better understanding of the functionalization of graphene and graphitic nanomaterials at the nano-scale, micro-scale, and macro-scale and the relationship between the techniques and how they relate to the changes in material properties of industrial importance. [ABSTRACT FROM AUTHOR]

Published
2020
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33. Researching the Complex, Hybrid, and Liminal Nature of Contemporary Promotional Cultures

Author

Somerville, Ian, Edwards, Lee, Somerville, Ian, and Edwards, Lee

Abstract

This thematic issue invited submissions that address the challenges of researching the complex, hybrid, and liminal nature of promotional cultures and the published articles include studies which reflect on the structures, technologies, agents, representations, effects, and ethics of promotion. They are united by a central question: What strategies do we use to explore and attempt to understand the assemblages of technologies, texts, networks, and actors in contemporary promotion? We hope the collection of perspectives gathered here help to address the challenges of researching the digital, excavating promotional ideologies, confronting professions, engaging audiences through academic work, and confronting the risks and realities of research that can equally promote change or speak into a vacuum.

Published
2022

34. Resituating the political in cultural intermediary work:charity sector public relations and communication

Author

Cronin, Anne, Edwards, Lee, Cronin, Anne, and Edwards, Lee

Abstract

Drawing on a case study of public relations in the UK charity sector, this article argues that cultural intermediary research urgently requires a more sustained focus on politics and the political as power relations, party politics, and political projects such as marketisation and neoliberalism. While wide-ranging research has analysed how cultural intermediaries mediate the relationship between culture and economy, this has been at the expense of a depth analysis of the political. Using our case study as a prompt, we highlight the diversity of ways that the political impacts cultural intermediary work and that cultural intermediary work may impact the political. We reveal the tensions that underpin practice as a result of the interactions between culture, the economy and politics, and show that the tighter the engagement of cultural intermediation with the political sphere, the more tensions must be negotiated, and the more compromised practitioners may feel.

Published
2022

35. Resituating the political in cultural intermediary work : charity sector public relations and communication

Author

Cronin, Anne, Edwards, Lee, Cronin, Anne, and Edwards, Lee

Abstract

Drawing on a case study of public relations in the UK charity sector, this article argues that cultural intermediary research urgently requires a more sustained focus on politics and the political as power relations, party politics, and political projects such as marketisation and neoliberalism. While wide-ranging research has analysed how cultural intermediaries mediate the relationship between culture and economy, this has been at the expense of a depth analysis of the political. Using our case study as a prompt, we highlight the diversity of ways that the political impacts cultural intermediary work and that cultural intermediary work may impact the political. We reveal the tensions that underpin practice as a result of the interactions between culture, the economy and politics, and show that the tighter the engagement of cultural intermediation with the political sphere, the more tensions must be negotiated, and the more compromised practitioners may feel.

Published
2022

36. Narrating the anxious market: in search of alternatives during global crises.

Author

Bourne, Clea, Mumby, Dennis, Munshi, Debashish, Das, Arindam, Roy Chaudhuri, Himadri, and Edwards, Lee

Subjects
MARKETING, CONSUMPTION (Economics), ANXIETY, CRISES, ELECTRICITY markets, VIRTUAL communications
Abstract

In this virtual roundtable, the editors of the special issue convened a discussion between three leading scholars in the fields of critical communication studies, CCT and marketing, to explore the roles, challenges and tensions that arise from the engagement of consumption and markets at the juncture of global crises. In the eclectic conversation, they critically probe the power imbalances in market narratives between the centre and the margin at moments of global crises and look towards alternative forms of markets and consumption culture. While sceptical of counter-market narratives that are appropriated by market mechanisms, they probe the opportunities for radical changes in the future that will subvert neoliberal arrangements and open the way to more equitable infrastructures of survival and overcoming, essential to our future. [ABSTRACT FROM AUTHOR]

Published
2023
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42. An organophotocatalytic late-stage N–CH3 oxidation of trialkylamines to N-formamides with O2 in continuous flow

Author

Mandigma, Mark John P., primary, Žurauskas, Jonas, additional, MacGregor, Callum I., additional, Edwards, Lee J., additional, Shahin, Ahmed, additional, d'Heureuse, Ludwig, additional, Yip, Philip, additional, Birch, David J. S., additional, Gruber, Thomas, additional, Heilmann, Jörg, additional, John, Matthew P., additional, and Barham, Joshua P., additional

Published
2022
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44. Organophotocatalytic late-stage N-CH3 oxidation of trialkylamines with O2 in continuous flow

Author

Mandigma, Mark John P., Žurauskas, Jonas, MacGregor, Callum I., Edwards, Lee J., Shahin, Ahmed, d’Heureusea, Ludwig, Yip, Philip, Birch, David J. S., Gruber, Thomas, Heilmann, Jörg, John, Matthew P., and Barham, Joshua P.

Subjects
QD
Abstract

We report an organophotocatalytic, N-CH3-selective oxidation of trialkylamines in continuous flow. Based on the 9,10-dicyanoanthracene (DCA) core, a new catalyst (DCAS) was designed with solubilizing groups for processing in flow which allowed harnessing of O2 as a benign reagent for late-stage photocatalytic N-CH3 oxidation of natural products and active pharmaceutical ingredients. These substrates bear functional groups which are not tolerated by previous methods. The organophotocatalytic process benefited from the flow parameters, affording cleaner reactions in short residence time of 13.5 mins and productivities of up to 0.65 g / day. Mechanistic studies found that catalyst derivatization not only enhanced solubility of the new catalyst compared to DCA, it profoundly diverted the photocatalytic reaction mechanism from singlet electron transfer (SET) reductive quenching with amines to energy transfer (EnT) with O2.

Published
2021

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