Fabrication and properties of gallium phosphide variable colour displays

The unique properties of single-junction gallium phosphide devices incorporating both red and green radiative recombination centers were investigated in application to the fabrication of monolithic 5 x 7 displays capable of displaying symbolic and alphanumeric information in a multicolor format. A number of potentially suitable material preparation techniques were evaluated in terms of both material properties and device performance. Optimum results were obtained for double liquid-phase-epitaxial process in which an open-tube dipping technique was used for n-layer growth and a sealed tipping procedure for subsequent p-layer growth. It was demonstrated that to prepare devices exhibiting a satisfactory range of dominant wavelengths which can be perceived as distinct emission colors extending from the red through green region of the visible spectrum involves a compromise between the material properties necessary for efficient red emission and those considered optimum for efficient green emission

Micro electrostatic precipitation for air treatment

Micro-Electrostatic precipitation uses combining impulses and dc voltage in order to charge and remove fine, sub-micron particles efficiently. Short impulses are expected to increase the precipitation efficiency and to reduce power consumption

Detectors—The ongoing revolution in scanning transmission electron microscopy and why this important to material characterization

Detectors are revolutionizing possibilities in scanning transmission electron microscopy because of the advent of direct electron detectors that record at a high quantum efficiency and with a high frame rate. This allows the whole back focal plane to be captured for each pixel in a scan and the dataset to be processed to reveal whichever features are of interest. There are many possible uses for this advance of direct relevance to understanding the nano- and atomic-scale structure of materials and heterostructures. This article gives our perspective of the current state of the field and some of the directions where it is likely to go next. First, a wider overview of the recent work in this area is given before two specific examples of its application are given: one is imaging strain in thin films and the other one is imaging changes in periodicity along the beam direction as a result of the formation of an ordered structure in an epitaxial thin film. This is followed by an outlook that presents future possible directions in this rapidly expanding field

Yabi: An online research environment for grid, high performance and cloud computing

Background There is a significant demand for creating pipelines or workflows in the life science discipline that chain a number of discrete compute and data intensive analysis tasks into sophisticated analysis procedures. This need has led to the development of general as well as domain-specific workflow environments that are either complex desktop applications or Internet-based applications. Complexities can arise when configuring these applications in heterogeneous compute and storage environments if the execution and data access models are not designed appropriately. These complexities manifest themselves through limited access to available HPC resources, significant overhead required to configure tools and inability for users to simply manage files across heterogenous HPC storage infrastructure. Results In this paper, we describe the architecture of a software system that is adaptable to a range of both pluggable execution and data backends in an open source implementation called Yabi. Enabling seamless and transparent access to heterogenous HPC environments at its core, Yabi then provides an analysis workflow environment that can create and reuse workflows as well as manage large amounts of both raw and processed data in a secure and flexible way across geographically distributed compute resources. Yabi can be used via a web-based environment to drag-and-drop tools to create sophisticated workflows. Yabi can also be accessed through the Yabi command line which is designed for users that are more comfortable with writing scripts or for enabling external workflow environments to leverage the features in Yabi. Configuring tools can be a significant overhead in workflow environments. Yabi greatly simplifies this task by enabling system administrators to configure as well as manage running tools via a web-based environment and without the need to write or edit software programs or scripts. In this paper, we highlight Yabi's capabilities through a range of bioinformatics use cases that arise from large-scale biomedical data analysis. Conclusion The Yabi system encapsulates considered design of both execution and data models, while abstracting technical details away from users who are not skilled in HPC and providing an intuitive drag-and-drop scalable web-based workflow environment where the same tools can also be accessed via a command line. Yabi is currently in use and deployed at multiple institutions and is available at http://ccg.murdoch.edu.au/yabi

Glasgow, Edinburgh, Mainz (GEM) Tagging System

The GEM tagging spectrometer was designed to make best use of the 100% DC MAMI-A beam for doing photoreaction experiments. As the location available for the spectrometer was in the Magnet Hall a non standard design was necessary so that the tagging magnet system could also act as electron beam handling system when the beam when the beam was required in Hall 2. This location also offered the possibility of parasitic operation in conjunction with experiments in Hall 2

Excitations in the Halo Nucleus He-6 Following The Li-7(gamma,p)He-6 Reaction

A broad excited state was observed in 6-He with energy E_x = 5 +/- 1 MeV and width Gamma = 3 +/- 1 MeV, following the reaction Li-7(gamma,p)He-6. The state is consistent with a number of broad resonances predicted by recent cluster model calculations. The well-established reaction mechanism, combined with a simple and transparent analysis procedure confers considerable validity to this observation.Comment: 3 pages of LaTeX, 3 figures in PostScript, approved for publication in Phys. Rev. C, August, 200

[Pd4(μ3-SbMe3)4(SbMe3)4]: A Pd(0) tetrahedron with μ3-bridging trimethylantimony ligands

The palladium(II) chlorostibine complex [PdCl2(SbMe2Cl)2]2 has a dimeric structure in the solid state, stabilized by hyper-coordination at the Lewis amphoteric Sb centers. Reaction with 8 equiv of MeLi forms [Pd4(μ3-SbMe3)4(SbMe3)4], whose structure comprises a tetrahedral Pd(0) core with four terminal SbMe3 ligands and four μ3-SbMe3 ligands, one capping each triangular Pd3 face. Density functional theory calculations, supported by energy decomposition analysis and the natural orbitals for chemical valence scheme, highlight significant donor and acceptor orbital contributions to the bonding between both the terminal and the bridging SbMe3 ligands and the Pd4 core

An experimental and analytical study of plasma closing switches filled with environmentally friendly gases

In recent years there has been a desire within the pulsed power community to find potential alternative gases to sulphur hexafluoride (SF6) for use within pulsed power systems. Within plasma closing switches (PCSs), the desire to use environmentally friendly gases has come as a result of environmental concerns over the emissions of currently used gases into the atmosphere and contributing to the global warming problem. One of the main issues in finding a suitable replacement gas or gases for use in PCSs is that the performance characteristics of a switch filled with an alternative gas or gas mixture should be comparable to the performance characteristics of conventional SF6-filled switches. The research presented in this paper is an expansion of previous work conducted and forms an experimental and analytical evaluation of breakdown characteristics in two commonly used PCS topologies (a two-electrode self-breakdown switch and a field distortion switch) when filled with different gases (air, oxygen-nitrogen mixtures, argon oxygen mixture, nitrogen and carbon dioxide) over a range of pressures from 0.1 MPa to 0.45 MPa and for a range of inter-electrode distances

Supporting care home residents in the last year of life through ‘Needs Rounds’: Development of a pre-implementation programme theory through a rapid collaborative online approach

2023 Macgregor, McCormack, Spilsbury, Hockley, Rutherford, Ogden, Soulsby, Mckenzie, Hanratty and Forbat.Background: Realist evaluation aims to address the knowledge to practice gap by explaining how an intervention is expected to work, as well as what is likely to impact upon the success of its implementation, by developing programme theories that link contexts, mechanisms and outcomes. Co-production approaches to the development of programme theories offer substantial benefits in addressing power relations, including and valuing different types of knowledge, and promoting buy-in from stakeholders while navigating the complex social systems in which innovations are embedded. This paper describes the co-production of an initial programme theory of how an evidence based intervention developed in Australia - called ‘Palliative Care Needs Rounds’ – might work in England and Scotland to support care home residents approaching their end of life. Methods: Using realist evaluation and iPARIHS (integrated Promoting Action on Research Implementation in Health Services) we sought to determine how contexts and mechanisms of change might shape implementation outcomes. Pre-intervention online interviews (n = 28) were conducted (February-April 2021), followed by four co-design online workshops with 43 participants (April-June 2021). The online interviews and workshops included a range of stakeholders, including care home staff, specialist palliative care staff, paramedics, general practitioners, and relatives of people living in care homes. Results: This methodology paper reports developments in realist evaluation and co-production methodologies, and how they were used to develop context, mechanisms, outcomes (CMOs) configurations, and chains of inference. The initial (pre-intervention) programme theory is used to illustrate this process. Two developments to iPARIHS are described. First, involving stakeholders in the collaborative co-design workshops created opportunities to commence facilitation. Second, we describe developing iPARIHS’ innovation component, to include novel stakeholder interpretations, perceptions and anticipated use of the intervention as they participated in workshop discussions. Conclusions: This rapid and robust co-production methodology draws on interactive collaborative research practices (interviews, workshop discussions of data, illustrative vignettes and visual methods). These innovative and engaging methods can be packaged for online processes to develop, describe and interrogate the CMOs in order to co-produce a programme theory. These approaches also commence facilitation and innovation, and can be adopted in other implementation science and realist studies