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The dynamical development of expanding Quark-gluon Plasma (QGP) flow is studied in a 3+1D fluid dynamical model with a globally symmetric, initial condition. We minimize fluctuations arising from complex dynamical processes at finite impact parameters and from fluctuating random initial conditions to have a conservative fluid dynamical background estimate for the statistical distributions of the thermodynamical parameters. We also avoid a phase transition in the equation of state, and we let the matter supercool during the expansion. Then central Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV are studied in an almost perfect fluid dynamical model, with azimuthally symmetric initial state generated in a dynamical flux-tube model. The general development of thermodynamical extensives are also shown for lower energies. We observe considerable deviations from a thermal equilibrium source as a consequence of the fluid dynamical expansion arising from a least fluctuating initial state.

The effect of hadronic rescattering on the elliptic flow has been investigated by the Cooper-Frye hadronization model from hydrodynamic evolution following by the afterburner hadronic rescattering model for 200 GeV/c Au + Au at 20-40% centrality. It is found that the hadronic rescattering can suppress elliptic flow $v_2$ in momentum space especially in lower transverse momentum region. In addition, the hadronic rescattering effects on transverse momentum spectra and anisotropy coordinate space of hadrons are studied., Comment: 6 pages, 5 figures

The $\Delta$-scaling method has been applied to the total multiplicity distribution of the relativistic ion collisions of p+p, C+C and Pb+Pb which were simulated by a Monte Carlo package, LUCIAE 3.0. It is found that the $\Delta$-scaling parameter decreases with the increasing of the system size. Moreover, the heat capacities of different mesons and baryons have been extracted from the event-by-event temperature fluctuation in the region of low transverse mass and they show the dropping trend with the increasing of impact parameter., Comment: version 2: major change: 4 pages, 3 figures; Proceeding of International Conference on "Strangeness in Quark Matter" (SQM2004), Cape Town, South Africa, Spet. 2004 (Submitted to J. Phys. G.)

The $\Delta$-scaling method has been applied to ultra-relativistic p+p, C+C and Pb+Pb collision data simulated using a high energy Monte Carlo package, LUCIAE 3.0. The $\Delta$-scaling is found to be valid for some physical variables, such as charged particle multiplicity, strange particle multiplicity and number of binary nucleon-nucleon collisions from these simulated nucleus-nucleus collisions over an extended energy ranging from $E_{lab}$ = 20 to 200 A GeV. In addition we derived information entropy from the multiplicity distribution as a function of beam energy for these collisions., Comment: 4 pages, 4 figures, 1 table; to appear in the July Issue of Chin. Phys. Lett.. Web Page: http://www.iop.org/EJ/journal/CPL