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71.
The classification of the Auslander-Reiten quivers of the local orders of finite lattice type is completed. For this purpose, it is shown—using the results of [7]—that to the list of the known Auslander-Reiten quivers of the local Bäckström orders of finite lattice type [11], [14] and of the local Gorenstein orders of finite type and their minimal overorders [18] one has to add two remaining types of valued translation quivers to obtain a complete list of all Auslander-Reiten quivers of the local orders of finite lattice type.  相似文献   
72.
In nucleus-nucleus collisions at the Relativistic Heavy Ion Collider (RHIC), one generically observes a strong medium-induced suppression of high- pT hadron production. This suppression is accounted for in models which assume a significant medium-induced radiative energy loss of high- pT parent partons produced in the collision. How can we further test the microscopic dynamics conjectured to underlie this abundant high- pT phenomenon? What can we learn about the dynamics of parton fragmentation, and what can we learn about the properties of the medium which modifies it? Given that inelastic parton scattering is expected to be the dominant source of partonic equilibration processes, can we use hard processes as an experimentally well-controlled window into QCD non-equilibrium dynamics? Here I review what has been achieved so far, and which novel opportunities open up with higher luminosity at RHIC, and with the wider kinematical range accessible soon at the LHC.Received: 15 February 2005, Published online: 3 June 2005PACS: 12.38.Mh, 24.85. + p  相似文献   
73.
One of the challenges in relating experimental measurements of the suppression in the number of J/psi mesons produced in heavy ion collisions to lattice QCD calculations is that whereas the lattice calculations treat J/psi mesons at rest, in a heavy ion collision a cc[over ] pair can have a significant velocity with respect to the hot fluid produced in the collision. The putative J/psi finds itself in a hot wind. We present the first rigorous nonperturbative calculation of the consequences of a wind velocity v on the screening length L(s) for a heavy quark-antiquark pair in hot N=4 supersymmetric QCD. We find L(s)(v,T)=f(v)[1-v(2)](1/4)/piT with f(v) only mildly dependent on v and the wind direction. This L(s)(v,T) approximately L(s)(0,T)/sqrt[gamma] velocity scaling, if realized in QCD, provides a significant additional source of J/psi suppression at transverse momenta which are high but within experimental reach.  相似文献   
74.
The high temperature transitions between 300 and 500 K of N,N'-bis(4-n-octyloxybenzal)-1,4-phenylenediamine are analyzed by scanning calorimetry, optical microscopy, light transmission measurement, thermomechanical analysis and X-ray diffraction. The prior assignment of mesophase structure K3/385.2/K2/388.2/K1/415.3/H'/422.2/G'/426.9/I/436.6/C/475.4/N/505.4/Melt (temperatures in K) has been extended by the suggestion that K1 to K3 are conformationally disordered crystals.  相似文献   
75.
It is widely accepted that a phenomenologically viable theory of jet quenching for heavy ion collisions requires the understanding of medium-induced parton energy loss beyond the limit of eikonal kinematics formulated by Baier–Dokshitzer–Mueller–Peigné–Schiff and Zakharov (BDMPS-Z). Here, we supplement a recently developed exact Monte Carlo implementation of the BDMPS-Z formalism with elementary physical requirements including exact energy-momentum conservation, a refined formulation of jet-medium interactions and a treatment of all parton branchings on the same footing. We document the changes induced by these physical requirements and we describe their kinematic origin.  相似文献   
76.
The iron(III) complexes of the tripodal benzimidazole‐containing ligands tris(2‐benzimidazolylmethyl)amine (ntb), bis(2‐benzimidazolylmethyl)(2‐hydroxyethyl)‐amine (bbimae) and tris(5,6‐dimethyl‐2‐benzimidazolylmethyl)amine (me2ntb) are structural and functional models for intradiol cleaving catechol dioxygenases. The complexes [Fe(ntb)Cl2]Cl · 3 CH3OH ( 1 ; P 1, a = 9.830(2) Å, b = 12.542(3) Å, c = 13.139(3) Å, α = 82.88(3)°, β = 73.45(3)°, γ = 85.53(3)°, V = 1539.2(6) Å3; Z = 2) and [Fe(bbimae)Cl2]Cl ( 2 ; P21/n, a = 7.461(2) Å, b = 18.994(5) Å, c = 14.515(4) Å, β = 98.22(2)°, V = 2035.8(9) Å3, Z = 4) have been characterized by X‐ray crystallography and spectroscopic methods. In the octahedrally coordinated complexes two cis coordination sites – essential for catechol binding – are occupied by chloride ligands. The significant intradiol cleaving catechol dioxygenase activity of the model complexes was examined using 3,5‐di‐tert‐butylcatechol as a substrate.  相似文献   
77.
78.
A comprehensive analysis of the application of the method of collective coordinates to the two dimensional Higgs model is given. First the instanton solution is derived, and the geometry of configuration space, and the construction of Schrodinger wave functionals are discussed. It is then explicitly verified that the Goldstone mode is the projection of the vacuum state onto the generator of the broken symmetry. The elimination of this Goldstone mode by means of the unitary gauge condition is demonstrated to the the crucial point in the construction of a consistent perturbation procedure. The parameter of the broken symmetry group is then used as the collective coordinate for field configurations around a minimum of the interaction. Throughout, the discussion is sufficiently detailed in order to facilitate the application of the method to other fields.  相似文献   
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