4,547 research outputs found

    Thermal energy storage material thermophysical property measurement and heat transfer impact

    Get PDF
    The thermophysical properties of salts having potential for thermal energy storage to provide peaking energy in conventional electric utility power plants were investigated. The power plants studied were the pressurized water reactor, boiling water reactor, supercritical steam reactor, and high temperature gas reactor. The salts considered were LiNO3, 63LiOH/37 LiCl eutectic, LiOH, and Na2B4O7. The thermal conductivity, specific heat (including latent heat of fusion), and density of each salt were measured for a temperature range of at least + or - 100 K of the measured melting point. Measurements were made with both reagent and commercial grades of each salt

    Anomalous hydrodynamics and "normal" fluids in rapidly rotating BECs

    Full text link
    In rapidly rotating bose systems we show that there is a region of anomalous hydrodynamics whilst the system is still condensed, which coincides with the mean field quantum Hall regime. An immediate consequence is the absence of a normal fluid in any conventional sense. However, even the superfluid hydrodynamics is not described by conventional Bernoulli and continuity equations. We show there are kinematic constraints which connect spatial variations of density and phase, that the positions of vortices are not the simplest description of the dynamics of such a fluid (despite their utility in describing the instantaneous state of the condensate) and that the most compact description allows solution of some illuminating examples of motion. We demonstrate, inter alia, a very simple relation between vortices and surface waves. We show the surface waves can form a "normal fluid" which absorbs energy and angular momentum from vortex motion in the trap. The time scale of this process is sensitive to the initial configuration of the vortices, which can lead to long-lived vortex patches - perhaps related to those observed at JILA.Comment: 4 pages; 1 sentence and references modifie

    Exact vortex nucleation and cooperative vortex tunneling in dilute BECs

    Full text link
    With the imminent advent of mesoscopic rotating BECs in the lowest Landau level (LLL) regime, we explore LLL vortex nucleation. An exact many-body analysis is presented in a weakly elliptical trap for up to 400 particles. Striking non-mean field features are exposed at filling factors >>1 . Eg near the critical rotation frequency pairs of energy levels approach each other with exponential accuracy. A physical interpretation is provided by requantising a mean field theory, where 1/N plays the role of Planck's constant, revealing two vortices cooperatively tunneling between classically degenerate energy minima. The tunnel splitting variation is described in terms of frequency, particle number and ellipticity.Comment: 4 pages,4 figure

    The Long and Winding Road: Archiving and Re-Using Qualitative Data from 12 Research Projects Spanning 16 Years

    Get PDF
    We describe a pilot project designed to assess the feasibility of re-use across 12 diverse qualitative datasets related to Human Immunodeficiency Virus (HIV) in the UK, from research projects undertaken between 1997 and 2013 – an approach which is chronically underused. First, we consider the sweeping biomedical changes and imperatives relating to HIV in this time frame, offering a rationale for data re-use at this point in the epidemic. We then reflexively situate the processes and procedures we devised for this study with reference to relevant methodological literature. Hammersley’s and Leonelli’s contributions have been particularly instructive through this process, and following their lead, we conclude with further considerations for those undertaking qualitative data re-use, reflecting on the extent to which qualitative data re-use as a practice requires attention to both the given and the constructed aspects of data when assembled as evidence

    The Chemsex study: drug use in sexual settings among gay and bisexual men in Lambeth, Southwark and Lewisham

    Get PDF

    Keeping Confidence: Responsibility and public health

    Get PDF
    Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV

    Keeping Confidence: Understanding the Law

    Get PDF
    Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV

    Keeping Confidence: Practice and procedure

    Get PDF
    Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV

    Keeping Confidence: Identifying resources

    Get PDF
    Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV. Catherine Dodds, Matthew Weait, Adam Bourne, Siri Egede, Kathie Jessup and Peter Weatherburn
    • …
    corecore