21,943 research outputs found
Effect of surface roughness on friction behaviour of steel under boundary lubrication
The friction behaviour of grinded and polished surfaces was evaluated by using a reciprocal sliding tester under lubrication with PAO, PAO + ZnDTP and PAO + ZnDTP + MoDTC. Friction coefficients on the smooth surfaces showed higher values compared to those on the rough surfaces. For lubrication incorporating PAO and PAO + ZnDTP + MoDTC, friction coefficients on both the smoothest and the roughest surfaces decreased with sliding time. On the other hand, friction coefficients between these extremes decreased with sliding time. In this paper, the effects of surface roughness on friction behaviour are discussed
Susceptibilities and the Phase Structure of a Chiral Model with Polyakov Loops
In an extension of the Nambu-Jona-Lasinio model where the quarks interact
with the temporal gluon field, represented by the Polyakov loop, we explore the
relation between the deconfinement and chiral phase transitions. The effect of
Polyakov loop dynamics on thermodynamic quantities, on the phase structure at
finite temperature and baryon density and on various susceptibilities is
presented. Particular emphasis is put on the behavior and properties of the
fluctuations of the (approximate) order parameters and their dependence on
temperature and net--quark number density. We also discuss how the phase
structure of the model is influenced by the coupling of the quarks to the
Polyakov loop.Comment: 18 pages, 22 figures; text rearranged and references added. results
and conclusions unchanged; final version accepted for publication in Phys.
Rev.
Effective chiral model with Polyakov loops and its application to hot/dense medium
We study the thermodynamics of the Nambu--Jona-Lasinio model with Polyakov
loops, where spontaneous chiral symmetry breaking and confinement are taken
into account. We focus on the phase structure of the model and explore the
susceptibilities associated with corresponding order parameters under the
mean-field approximation.Comment: 4 pages, 1 figure, to appear in the proceedings of the Yukawa
International Seminars (YKIS) 2006, Nov.27-Dec.1, 2006, Kyoto, Japa
Susceptibilities and the Phase Structure of an Effective Chiral Model with Polyakov Loops
In the Nambu--Jona-Lasinio model with Polyakov loops, we explore the relation
between the deconfinement and chiral phase transitions within the mean-field
approximation. We focus on the phase structure of the model and study the
susceptibilities associated with corresponding order parameters.Comment: 6 pages, 2 figures, contribution to the proceedings of the 19th
International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions
(QM2006), November 14-20 2006, Shanghai, Chin
QCD phase diagram and charge fluctuations
We discuss the phase structure and fluctuations of conserved charges in two
flavor QCD. The importance of the density fluctuations to probe the existence
of the critical end point is summarized. The role of these fluctuations to
identify the first order phase transition in the presence of spinodal phase
separation is also discussed.Comment: 8 pages, 8 figures, plenary talk given at the 19th International
Conference on Ultrarelativistic Nucleus-Nucleus Collisions: Quark Matter 2006
(QM 2006), Shanghai, China, 14-20 Nov 200
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