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Investigating the Site of Newton's Laboratory in Trinity College, Cambridge
It is not generally known that over the
course of some thirty years, Isaac Newton
carried out around four hundred chemical
experiments in a private laboratory located in
the walled garden immediately below his
rooms in Trinity College, Cambridge. The
exact location of his laboratory has long been a
source of conjecture and this article describes
a survey undertaken to determine both the
possible site of the laboratory as well as that of
the rubbish pit in which Newton would have
disposed of the waste materials generated in
his chemical experiments. The results are
believed to be of sufficient interest to justify
continuation of the investigation
Agape and Ecstasy: considering post-secular orientations
This article addresses issues contemporary sexual and religious identity and orientation through an exploration of the unexpected compatibility of post-secular and queer theories
Free to Write: a case study in the impact of cultural history research and creative writing practice.
An account of LJMU's Free to Write project, exploring the impact of creative writing practice, informed by cultural-historical research, on prisoners and probationers
Electromagnetic analysis of a synchronous reluctance motor with single tooth windings.
This paper explores some key electromagnetic design aspects of a synchronous reluctance motor which is equipped with single tooth windings (i.e. fractional slot-concentrated windings). The analyzed machine, a 6 slot 4 pole motor, utilizes a segmented stator core structure for ease of coil winding, pre-assembly and facilitation of high slot fill factors (~60%). The impact on the motors torque producing capability and its power factor of these inter-segment air-gaps between the stator segments is investigated through 2D FEA studies where it is shown that they have a low impact. From previous studies, torque ripple is a known issue with this particular slot-pole combination of synchronous reluctance motor and the use of two different commercially available semi-magnetic slot wedges are investigated as a method to improve torque quality. An analytical analysis of continuous rotor skewing is also investigated as an attempt to reduce the torque ripple. Finally, it is shown through a combination of 2D & 3D FEA studies in conjunction with experimentally derived results on a prototype machine that axial fringing effects cannot be ignored when predicting the q-axis reactance in such machines. A comparison of measured orthogonal axis flux linkages/reactance with 3D FEA studies is presented for the first time
Mesospheric gravity wave momentum flux estimation using hybrid Doppler interferometry
Published: 12 June 2017Mesospheric gravity wave (GW) momentum flux estimates using data from multibeam Buckland Park MF radar (34.6° S, 138.5° E) experiments (conducted from July 1997 to June 1998) are presented. On transmission, five Doppler beams were symmetrically steered about the zenith (one zenith beam and four off-zenith beams in the cardinal directions). The received beams were analysed with hybrid Doppler interferometry (HDI) (Holdsworth and Reid, 1998), principally to determine the radial velocities of the effective scattering centres illuminated by the radar. The methodology of Thorsen et al. (1997), later re-introduced by Hocking (2005) and since extensively applied to meteor radar returns, was used to estimate components of Reynolds stress due to propagating GWs and/or turbulence in the radar resolution volume. Physically reasonable momentum flux estimates are derived from the Reynolds stress components, which are also verified using a simple radar model incorporating GW-induced wind perturbations. On the basis of these results, we recommend the intercomparison of momentum flux estimates between co-located meteor radars and vertical-beam interferometric MF radars. It is envisaged that such intercomparisons will assist with the clarification of recent concerns (e.g. Vincent et al., 2010) of the accuracy of the meteor radar technique.Andrew J. Spargo, Iain M. Reid, Andrew D. MacKinnon, and David A. Holdswort
Non-collinear magnetic structures: a possible cause for current induced switching
Current induced switching in Co/Cu/Co trilayers is described in terms of
ab-initio determined magnetic twisting energies and corresponding sheet
resistances. In viewing the twisting energy as an energy flux the
characteristic time thereof is evaluated by means of the
Landau-Lifshitz-Gilbert equation using ab-initio parameters. The obtained
switching times are in very good agreement with available experimental data. In
terms of the calculated currents, scalar quantities since a classical Ohm's law
is applied, critical currents needed to switch magnetic configurations from
parallel to antiparallel and vice versa can unambiguously be defined. It is
found that the magnetoresistance viewed as a function of the current is
essentially determined by the twisting energy as a function of the relative
angle between the orientations of the magnetization in the magnetic slabs,
which in turn can also explain in particular cases the fact that after having
switched off the current the system remains in the switched magnetic
configuration. For all ab-initio type calculations the fully relativistic
Screened Korringa-Kohn-Rostoker method and the corresponding Kubo-Greenwood
equation in the context of density functional theory are applied.Comment: 20 pages, 4 tables and 15 figures, submitted to PR
Seasonal MLT-region nightglow intensities, temperatures, and emission heights at a Southern Hemisphere midlatitude site
We consider 5 years of spectrometer measurements of OH(6–2) and O2(0–1) airglow emission intensities and temperatures made near Adelaide, Australia (35° S, 138° E), between September 2001 and August 2006 and compare them with measurements of the same parameters from at the same site using an airglow imager, with the intensities of the OH(8–3) and O(1S) emissions made with a filter photometer, and with 2 years of Aura MLS (Microwave Limb Sounder) v3.3 temperatures and 4.5 years of TIMED SABER (Thermosphere Ionosphere Mesosphere Energetics and Dynamics Sounding of the Atmosphere using Broadband Emission Radiometry) v2.0 temperatures for the same site. We also consider whether we can recover the actual emission heights from the intercomparison of the ground-based and satellite observations. We find a significant improvement in the correlation between the spectrometer OH and SABER temperatures by interpolating the latter to constant density surfaces determined using a meteor radar.Iain M. Reid, Andrew J. Spargo, Jonathan M. Woithe, Andrew R. Klekociuk, Joel P. Younger and Gulamabas G. Sivje
An Aboriginal-driven program to prevent, control and manage nutrition-related 'lifestyle' diseases including diabetes
HRTEM study of orthorhombic zirconia in MgO-PSZ
High-resolution transmission electron microscopy (HRTEM) was used to study the phase of orthorhombic ZrO2 formed in magnesia partially stabilized zirconia (MgO-PSZ) during HRTEM specimen preparation. Based on the three reported crystal structures of orthorhombic ZrO2, with the space groups Pbcm, Pbc2(1) and Pbca, here it is shown that orthorhombic ZrO2 formed in MgO-PSZ has the Pbcm structure
Towards the evolution of style: Einstein’s garden and somewhere between the sky and the sea
The purpose of this research was to explore composition for dance and opera within a collaborative framework. The compositional works were developed after researching modern Australian ballet and opera. Along the journey, I discovered examples of works that were personally inspiring on a number of levels: in the music, text, staging, direction, choreography, scenery, and use of imagery. The elements that resounded with me were then adapted into my own compositions and those elements are responsible for steering my works in a particular direction when it came to performance. I conducted a musical analysis of my contemporary dance work Einstein’s Garden and my chamber opera Somewhere Between the Sky and the Sea, outlining the background and evolution of each work, including compositional stylistic evolution; musical aims; materials and instrumentation; structural plans; choice of tonality; compositional processes and collaboration with the performers; to discussion of the particular staging requirements, and a review of the overall collaboration and production process. In the Einstein’s Garden analysis, I explored the relationship between Albert Einstein, science and music. In the Somewhere between the Sky and the Sea analysis, I studied Portuguese and Spanish music influences on the chamber opera as well as different forms of text setting. I then examined the context of the works and the influence that undertaking musical research had upon my own compositions
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