5,208 research outputs found
Compressible vortex loops: effect of nozzle geometry
Vortex loops are fundamental building blocks of supersonic free jets. Isolating them allows for an easier study and better understanding of such flows. The present study looks at the behaviour of compressible vortex loops of different shapes, generated due to the diffraction of a shock wave from a shock tube with different exit nozzle geometries. These include a 15 mm diameter circular nozzle, two elliptical nozzles with minor to major axis ratios of 0.4 and 0.6, a 30 × 30 mm square nozzle, and finally two exotic nozzles resembling a pair of lips with minor to major axis ratios of 0.2 and 0.5. The experiments were performed for diaphragm pressure ratios of P4/P1=4, 8, and 12, with P4 and P1 being the pressures within the high pressure and low pressure compartments of the shock tube, respectively. High-speed schlieren photography as well as PIV measurements of both stream-wise and head-on flows have been conducted
Magnetic studies of the lightly Ru doped perovskite rhodates Sr(Ru,Rh)O
The solid solution between the ferromagnetic metal SrRuO and the enhanced
paramagnetic metal SrRhO was recently reported [K. Yamaura et al., Phys.
Rev. B 69 (2004) 024410], and an unexpected feature was found in the specific
heat data at =0.9 of SrRuRhO. The feature was reinvestigated
further by characterizing additional samples with various Ru concentrations in
the vicinity of =0.9. Specific heat and magnetic susceptibility data
indicate that the feature reflects a peculiar magnetism of the doped
perovskite, which appears only in the very narrow composition range
0.850.95.Comment: Accepted for publication in a special issue of Physica B (the
proceedings of SCES04
Spin melting and refreezing driven by uniaxial compression on a dipolar hexagonal plate
We investigate freezing characteristics of a finite dipolar hexagonal plate
by the Monte Carlo simulation. The hexagonal plate is cut out from a piled
triangular lattice of three layers with FCC-like (ABCABC) stacking structure.
In the present study an annealing simulation is performed for the dipolar plate
uniaxially compressed in the direction of layer-piling. We find spin melting
and refreezing driven by the uniaxial compression. Each of the melting and
refreezing corresponds one-to-one with a change of the ground states induced by
compression. The freezing temperatures of the ground-state orders differ
significantly from each other, which gives rise to the spin melting and
refreezing of the present interest. We argue that these phenomena are
originated by a finite size effect combined with peculiar anisotropic nature of
the dipole-dipole interaction.Comment: Proceedings of the Highly Frustrated Magnetism (HFM2006) conference.
To appear in a special issue of J. Phys. Condens. Matte
Fine-grained rims surrounding chondrules in the carbonate-poor lithology of the Tagish Lake carbonaceous chondrite
第3回極域科学シンポジウム/第35回南極隕石シンポジウム 11月30日(金) 国立国語研究所 2階講
A Quantum Beam Driver for the Future Inertial Fusion
Several heavy ion drivers for the inertial fusion
have been proposed in Europe and US
based on the existing the RF technology and the
linear induction linac technology, though their
concepts don’t still achieve the reality in a gigantic
large scale. Developing accelerator technology
may allow a compact and relatively
cheap quantum beam driver for the future inertial
fusion as an alternative scheme..
A Quantum Beam Driver for the Future Inertial Fusion
Several heavy ion drivers for the inertial fusion
have been proposed in Europe and US
based on the existing the RF technology and the
linear induction linac technology, though their
concepts don’t still achieve the reality in a gigantic
large scale. Developing accelerator technology
may allow a compact and relatively
cheap quantum beam driver for the future inertial
fusion as an alternative scheme..
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