Hopf algebras and characters of classical groups

Schur functions provide an integral basis of the ring of symmetric functions. It is shown that this ring has a natural Hopf algebra structure by identifying the appropriate product, coproduct, unit, counit and antipode, and their properties. Characters of covariant tensor irreducible representations of the classical groups GL(n), O(n) and Sp(n) are then expressed in terms of Schur functions, and the Hopf algebra is exploited in the determination of group-subgroup branching rules and the decomposition of tensor products. The analysis is carried out in terms of n-independent universal characters. The corresponding rings, CharGL, CharO and CharSp, of universal characters each have their own natural Hopf algebra structure. The appropriate product, coproduct, unit, counit and antipode are identified in each case.Comment: 9 pages. Uses jpconf.cls and jpconf11.clo. Presented by RCK at SSPCM'07, Myczkowce, Poland, Sept 200

A carbon dioxide reduction unit using Bosch reaction and expendable catalyst cartridges

Catalytic carbon dioxide reduction cartridge for oxygen recovery in life support systems of long term manned space flight

Bosch CO2 Reduction System Development

Development of a Bosch process CO2 reduction unit was continued, and, by means of hardware modifications, the performance was substantially improved. Benefits of the hardware upgrading were demonstrated by extensive unit operation and data acquisition in the laboratory. This work was accomplished on a cold seal configuration of the Bosch unit

The non-metallic materials sample array

The Non-Metallic Materials Sample Array (MSA) was flown as verification flight instrumentation (VFI) on both Spacelab 1 (SL-1) and Spacelab 2 (SL-2). The basis for materials selection was either previous flight history or probable flight suitability based upon analysis. The observed changes in the optical properties of the exposed materials are, in general, quite minimal; however, this data represents the short exposure of two Space Shuttle missions, and no attempt should be made to extrapolate the long-term exposure. The MSA was in orbit for 10 days at approximately 240 km on SL-1 and for 7 days at approximately 315 km on SL-2. The array was exposed to the solar flux for only a portion of the time in orbit

Doing it differently: Engaging interview participants with imaginative variation

Imaginative variation was identified by Husserl (1936/1970) as a phenomenological technique for the purpose of elucidating the manner in which phenomena appear to consciousness. Briefly, by engaging in the phenomenological reduction and using imaginative variation, phenomenologists are able to describe the experience of consciousness, having stepped outside of the natural attitude through the epochē. Imaginative variation is a stage aimed at explicating the structures of experience, and is best described as a mental experiment. Features of the experience are imaginatively altered in order to view the phenomenon under investigation from varying perspectives. Husserl argued that this process will reveal the essences of an experience, as only those aspects that are invariant to the experience of the phenomenon will not be able to change through the variation. Often in qualitative research interviews, participants struggle to articulate or verbalise their experiences. The purpose of this article is to detail a radical and novel way of using imaginative variation with interview participants, by asking the participants to engage with imaginative variation, in order to produce a rich and insightful experiential account of a phenomenon. We will discuss how the first author successfully used imaginative variation in this way in her study of the erotic experience of bondage, discipline, dominance & submission, and sadism & masochism (BDSM), before considering the usefulness of this technique when applied to areas of study beyond sexuality

Simplified quantum logic with trapped ions

We describe a simplified scheme for quantum logic with a collection of laser-cooled trapped atomic ions. Building on the scheme of Cirac and Zoller, we show how the fundamental controlled-NOT gate between a collective mode of ion motion and the internal states of a single ion can be reduced to a single laser pulse, and the need for a third auxiliary internal electronic state can be eliminated.Comment: 8 pages, PostScript, submitted to Physical Review A, Rapid Communication