Steven Matthews

Microwave activation of electrochemical processes: convection, thermal gradients and hot spot formation at the electrode|solution interface

Microwave activation of electrochemical processes is possible by self-focussing of intense microwave radiation at the electrode|solution (electrolyte) interface of an electrode immersed in a solution and placed in a microwave cavity. Considerable changes in voltammetric current responses are observed experimentally for the one-electron reduction of Ru(NH3)63+ in aqueous 0.1 M KCl and for the stepwise two-electron reduction of the methylviologen dication (MV2+) in aqueous 0.1 M NaCl. The formation and interconversion of two distinct forms of solid deposits, MVam0 and MVcryst0, on a mercury electrode surface is investigated, both in the presence of microwave activation and with conventional heating. It is shown that microwave activation achieves (i) high temperatures in the vicinity of the electrode, (ii) thermal desorption of deposits from the electrode surface and (iii) limiting currents an order of magnitude higher compared to those induced by conventional isothermal heating to the same electrode temperature.A simple physical model based on Joule heating of the aqueous solution phase is employed in a finite element simulation (FIDAPTM) procedure to explain the differences observed experimentally between conventional heating and microwave activation. Based on the comparison of simulation and experimental data, a considerable thermal gradient and ‘hot spot ’ region in the diffusion layer of the electrode, together with convective mass transport are proposed.

Microwave Activated Voltammetry: The Thermally Enhanced Anodic Stripping Detection of Cadmium

In situ microwave activation of electrochemical processes in a novel electrochemical cell, in which intense microwave radiation is focused locally into the region at the electrode surface–solution interface, is shown to allow high-temperature voltammetry experiments at 100 µm Pt disk electrodes. Factors such as the cell geometry and the deposition of a thin film of mercury are shown to influence the microwave effect.The detection of trace metals or impurities by anodic stripping voltammetry is a routinely applied procedure with applications especially in rapid online monitoring, in remote place analysis, or for extremely dilute samples. For cadmium detection by anodic stripping voltammetry microwave radiation is demonstrated to strongly affect the accumulation process but not the stripping process. Calibration of the effects induced by microwave radiation on the experimentally observed voltammetric data, based on the equilibrium potentials for the Fe(CN)64–/3– and the Ru(NH3)63+/2+ redox systems, demonstrates that the data obtained are consistent with a thermally enhanced process. The temperature achievable at the electrode–solution interface before boiling and cavitation occurs, is shown to be strongly dependent on the type of electrode material and surface morphology. At a mercury film electrode deposited on platinum temperatures in excess of 150 °C can be applied in voltammetric experiments in a constant heating mode.

Meditations and monologues: Beckett’s mid-late prose on the radio

This chapter focuses upon the framing materials used by the BBC when broadcasting performances of Beckett’s prose, from 1957 to his death in 1989. Despite the notorious abstraction and difficulty of these works, the Third Programme and then Radio Three, perhaps surprisingly, scheduled broadcasts of much of the late prose writing, often at the time of its publication in English. The BBC’s Written Archive Centre (WAC) at Caversham contains a plethora of material relating to the organisation of these broadcasts, some of which is considered here. The bulk of the chapter, however, thinks through the way the billing, and the spoken introductions to the broadcasts (often scripted by Martin Esslin), raise questions about the genres and kinds of writing that these later prose texts are.

Finding Consonance in the Disparities: Geoffrey Hill, John Milton, and Modernist Poetics

This article considers the technical features which Geoffrey Hill has appropriated from his precursor John Milton. These features enabled Hill to evolve a poetics, in his recent work, which is cognizant of the formal possibilities of modernism, but which overcomes their political and cultural dangers. Hills Miltonic poetics, alternatively, offer a politics, and ultimately a metaphysics, which understands fine distinctions, and specific unities, between its often recalcitrant materials. While drawing upon Hills critical responses to Milton, the article also deploys materials from the archive to consider the cruxes out of which some of Hills recent work has found its instigation.

You can see some eagles. And hear the trumpets: The Literary and Political Hinterland of T.S. Eliot's Coriolan

There has been an increased amount of scholarly interest lately in T.S. Eliots unfinished sequence, Coriolan (1932)—interest drawn from its Shakespearian allusiveness, and from analysis of this writings particularly rebarbative, jarring poetic. Although, however, the two parts of the sequence published by Eliot are acknowledged as being his nearest approach to poetic commentary upon contemporary political ideas, little criticism exists establishing the hinterland of the political thought, with which Eliot was most familiar, as editor of the Criterion. Coriolan emerges at a time when the lure of fascism pulled hardest at Eliots sensibility. This article reviews the full political context provided by Eliots journal, as well as considering the connections between that political engagement and the readings of Shakespeare he was also promulgating through this forum, in order to provide a more complex sense than hitherto of the diverse pressures underlying the unsettled nature of the existing Coriolan poems.

Provincialism and the Modern Diaspora: T. S. Eliot and David Jones

This article considers how T. S. Eliots promotion of the work of the Anglo-Welsh poet David Jones after the Second World War further involved him in a process of considering the resonances of the local and familiar as operative within the displacements of modernity. This promotion therefore retrospectively prioritized an aspect of Eliots poetics which had been present, but occluded, all along. Conversely, the article considers how similar resonances in Joness own work were enhanced by his encounter with Eliots translation of the Francophone Caribbean poet St-John Perses Anabase, an encounter which enabled Jones to establish an idiom responsive to the divergent cultural affinities inherent in ‘our situation’.