31,084 research outputs found
Transition from Ekman flow to Taylor vortex flow in superfluid helium
By numerically computing the steady axisymmetric flow of helium II confined
inside a finite aspect ratio Couette annulus, we determine the transition from
Ekman flow to Taylor vortex flow as a function of temperature and aspect
ratio.We find that the low-Reynolds number flow is quite different to that of a
classical fluid, particularly at lower temperatures.At high aspect ratio our
results confirm the existing linear stability theory of the onset of Taylor
vortices, which assumes infinitely long cylinders.Comment: 12 pages, 8 figures; submitte
Bis[μ-bis(diphenylphosphino)methane-К²P:P’]bis[(saccharinato-КN)- palladium(I)] dichloromethane solvate
The dimeric palladium(I) saccharinate complex [Pd₂(sac)₂(dppm)₂], has been characterized as its di¬chloro¬methane solvate, i.e. [Pd₂(C₇H₄NO₃S)₂(C₂₅H₂₂P₂)₂]•CH₂Cl₂. The complex features a Pd—Pd bond bridged by two dppm ligands, with the saccharinate ligands N-bonded trans to the Pd—Pd bond
Development of a superconductor magnetic suspension and balance prototype facility for studying the feasibility of applying this technique to large scale aerodynamic testing
The basic research and development work towards proving the feasibility of operating an all-superconductor magnetic suspension and balance device for aerodynamic testing is presented. The feasibility of applying a quasi-six-degree-of freedom free support technique to dynamic stability research was studied along with the design concepts and parameters for applying magnetic suspension techniques to large-scale aerodynamic facilities. A prototype aerodynamic test facility was implemented. Relevant aspects of the development of the prototype facility are described in three sections: (1) design characteristics; (2) operational characteristics; and (3) scaling to larger facilities
Population Health Needs Analysis: Victims of Modern Slavery and Human Trafficking in the UK
Modern slavery and human trafficking in the United Kingdom presents a series of new challenges for those working within the healthcare sector (Dalphins, 2016). Healthcare professionals have unique access to those involved in modern slavery, with over 88 percent of survivors reporting that they had accessed medical care on numerous occasions throughout their ordeal (Polaris Project, 2016). The variation in victim demographic, the differing forms of exploitation experienced and the traumatic nature of their ordeal can greatly affect the health of modern slavery victims (Adams, 2012). The enormity of the issue must be acknowledged and pre-emptive action taken to overcome barriers to satisfactory health and ultimately end the cycle of exploitation
Multi-component Force Balance Control Systems Final Report
Technique and apparatus for drag, lift, and pitch force measurements in hypersonic wind tunnel
Experimental Study of the Role of Atomic Interactions on Quantum Transport
We report an experimental study of quantum transport for atoms confined in a
periodic potential and compare between thermal and BEC initial conditions. We
observe ballistic transport for all values of well depth and initial
conditions, and the measured expansion velocity for thermal atoms is in
excellent agreement with a single-particle model. For weak wells, the expansion
of the BEC is also in excellent agreement with single-particle theory, using an
effective temperature. We observe a crossover to a new regime for the BEC case
as the well depth is increased, indicating the importance of interactions on
quantum transport.Comment: 4 pages, 3 figure
Extent of regretted sexual intercourse among young teenagers in Scotland: a cross sectional survey
No abstract available
High-Mobility Few-Layer Graphene Field Effect Transistors Fabricated on Epitaxial Ferroelectric Gate Oxides
The carrier mobility \mu of few-layer graphene (FLG) field-effect transistors
increases ten-fold when the SiO_2 substrate is replaced by single-crystal
epitaxial Pb(Zr_0.2Ti_0.8)O_3 (PZT). In the electron-only regime of the FLG,
\mu reaches 7x10^4 cm^2/Vs at 300K for n = 2.4x10^12/cm^2, 70% of the intrinsic
limit set by longitudinal acoustic (LA) phonons; it increases to 1.4x10^5
cm^2/Vs at low temperature. The temperature-dependent resistivity \rho(T)
reveals a clear signature of LA phonon scattering, yielding a deformation
potential D = 7.8+/-0.5 eV.Comment: 5 pages, 4 figure
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