Preparation and sorbent properties of alkyl and aryl ammonium polyphosphates

Imperial Users onl

United Kingdom: an increasingly differentiated profession

One of a selection of twelve country reports written as a contribution to the international Changing Academic Profession study that features over 20 countries. Each chapter addresses the issues of relevance, internationalisation and management and their implications for the academic profession in a particular country. These are: Australia, Brazil, the Czech Republic, Finland, Germany, Hong Kong, Japan, Malaysia, Norway, Portugal and South Africa, as well as the UK

Excellence in teaching and learning: A review of the literature for the Higher Education Academy

The Higher Education Academy commissioned a review of the literature on excellence in learning and teaching in higher education to enhance the higher education sector’s understanding of the varied conceptualisations and usages of the term ‘excellence’ and consider the implications for future policy and practice in relation to promoting and developing excellence. The literature searched included published research in the form of journal articles; books; reports from UK policy bodies and other agencies; as well as ‘grey’ literature. It covered conceptual studies, academic critiques and research studies on learning and teaching, as well as policy documents. Within a diverse and expanding system of higher education, such as in the UK, discourse on teaching and student learning highlights the tensions between different notions of excellence – for example, excellence as a positional good for students, as an aspirational target for continuous quality enhancement, as a form of reputational advantage for higher education institutions or as a means for achieving governmental economic and social goals. The review addressed questions of conceptualisations and usage at different (but interlinked) levels: system-wide; institutional; departmental; individual, and from two different perspectives, teaching and student learning

Mode-locking in advection-reaction-diffusion systems: an invariant manifold perspective

Fronts propagating in two-dimensional advection-reaction-diffusion (ARD) systems exhibit rich topological structure. When the underlying fluid flow is periodic in space and time, the reaction front can lock to the driving frequency. We explain this mode-locking phenomenon using so-called burning invariant manifolds (BIMs). In fact, the mode-locked profile is delineated by a BIM attached to a relative periodic orbit (RPO) of the front element dynamics. Changes in the type (and loss) of mode-locking can be understood in terms of local and global bifurcations of the RPOs and their BIMs. We illustrate these concepts numerically using a chain of alternating vortices in a channel geometry.Comment: 9 pages, 13 figure

Rendezvous radar for the orbital maneuvering vehicle

This paper describes the development of the Rendezvous Radar Set (RRS) for the Orbital Maneuvering Vehicle (OMV) for the National Aeronautics and Space Administration (NASA). The RRS was to be used to locate, and then provide vectoring information to, target satellites (or Shuttle or Space Station) to aid the OMV in making a minimum-fuel-consumption approach and rendezvous. The RRS design is that of an X-Band, all solid-state, monopulse tracking, frequency hopping, pulse-Doppler radar system. The development of the radar was terminated when the OMV prime contract to TRW was terminated by NASA. At the time of the termination, the development was in the circuit design stage. The system design was virtually completed, the PDR had been held. The RRS design was based on Motorola's experiences, both in the design and production of radar systems for the US Army and in the design and production of hi-rel communications systems for NASA space programs. Experience in these fields was combined with the latest digital signal processor and micro-processor technology to design a light-weight, low-power, spaceborne radar. The antenna and antenna positioner (gimbals) technology developed for the RRS is now being used in the satellite-to-satellite communication link design for Motorola's Iridium telecommunications system

Rendezvous radar for the orbital maneuvering vehicle

The Rendezvous Radar Set (RRS) was designed at Motorola's Strategic Electronics Division in Chandler, Arizona, to be a key subsystem aboard NASA's Orbital Maneuvering Vehicle (OMV). The unmanned OMV, which was under development at TRW's Federal Systems Division in Redondo Beach, California, was designed to supplement the Shuttle's satellite delivery, retrieval, and maneuvering activities. The RRS was to be used to locate and then provide the OMV with vectoring information to the target satellite (or Shuttle or Space Station) to aid the OMV in making a minimum fuel consumption approach and rendezvous. The OMV development program was halted by NASA in 1990 just as parts were being ordered for the RRS engineering model. The paper presented describes the RRS design and then discusses new technologies, either under development or planned for development at Motorola, that can be applied to radar or alternative sensor solutions for the Automated Rendezvous and Capture problem