2,888 research outputs found

    Quark Condensates in Nuclear Matter in the Global Color Symmetry Model of QCD

    Full text link
    With the global color symmetry model being extended to finite chemical potential, we study the density dependence of the local and nonlocal scalar quark condensates in nuclear matter. The calculated results indicate that the quark condensates increase smoothly with the increasing of nuclear matter density before the critical value (about 12ρ0\rho_0) is reached. It also manifests that the chiral symmetry is restored suddenly as the density of nuclear matter reaches its critical value. Meanwhile, the nonlocal quark condensate in nuclear matter changes nonmonotonously against the space-time distance among the quarks.Comment: 15 pages, 3 figure

    Reevaluation of the density dependence of nucleon radius and mass in the global color symmetry model of QCD

    Full text link
    With the global color symmetry model (GCM) at finite chemical potential, the density dependence of the bag constant, the total energy and the radius of a nucleon in nuclear matter is investigated. A relation between the nuclear matter density and the chemical potential with the action of QCD being taken into account is obtained. A maximal nuclear matter density for the existence of the bag with three quarks confined within is given. The calculated results indicate that, before the maximal density is reached, the bag constant and the total energy of a nucleon decrease, and the radius of a nucleon increases slowly, with the increasing of the nuclear matter density. As the maximal nuclear matter density is reached, the mass of the nucleon vanishes and the radius becomes infinite suddenly. It manifests that a phase transition from nucleons to quarks takes place.Comment: 18 pages, 3 figure

    Tris(5,6-dimethyl-1H-benzimidazole-κN 3)(pyridine-2,6-dicarboxyl­ato-κ3 O 2,N,O 6)nickel(II)

    Get PDF
    The title mononuclear complex, [Ni(C7H3NO4)(C9H10N2)3], shows a central NiII atom which is coordinated by two carboxyl­ate O atoms and the N atom from a pyridine-2,6-dicarboxyl­ate ligand and by three N atoms from different 5,6-dimethyl-1H-­benzimidazole ligands in a distorted octa­hedral geometry. The crystal structure shows intermolecular N—H⋯O hydrogen bonds

    Tris(1H-benzimidazole-κN 3)(pyridine-2,6-dicarb­oxy­lato-κ3 O 2,N,O 6)nickel(II)

    Get PDF
    In the title complex, [Ni(C7H3NO4)(C7H6N2)3], the NiII ion is coordinated by two carboxyl­ate O atoms and the N atom from a pyridine-2,6-dicarboxyl­ate ligand and by three N atoms from three benzimidazole ligands to form a slightly distorted octa­hedral geometry. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds to form a three-dimensional network

    Optimizing production scheduling of steel plate hot rolling for economic load dispatch under time-of-use electricity pricing

    Get PDF
    Time-of-Use (TOU) electricity pricing provides an opportunity for industrial users to cut electricity costs. Although many methods for Economic Load Dispatch (ELD) under TOU pricing in continuous industrial processing have been proposed, there are still difficulties in batch-type processing since power load units are not directly adjustable and nonlinearly depend on production planning and scheduling. In this paper, for hot rolling, a typical batch-type and energy intensive process in steel industry, a production scheduling optimization model for ELD is proposed under TOU pricing, in which the objective is to minimize electricity costs while considering penalties caused by jumps between adjacent slabs. A NSGA-II based multi-objective production scheduling algorithm is developed to obtain Pareto-optimal solutions, and then TOPSIS based multi-criteria decision-making is performed to recommend an optimal solution to facilitate filed operation. Experimental results and analyses show that the proposed method cuts electricity costs in production, especially in case of allowance for penalty score increase in a certain range. Further analyses show that the proposed method has effect on peak load regulation of power grid.Comment: 13 pages, 6 figures, 4 table

    Casimir effect with a helix torus boundary condition

    Full text link
    We use the generalized Chowla-Selberg formula to consider the Casimir effect of a scalar field with a helix torus boundary condition in the flat (D+1D+1)-dimensional spacetime. We obtain the exact results of the Casimir energy density and pressure for any DD for both massless and massive scalar fields. The numerical calculation indicates that once the topology of spacetime is fixed, the ratio of the sizes of the helix will be a decisive factor. There is a critical value rcritr_{crit} of the ratio rr of the lengths at which the pressure vanishes. The pressure changes from negative to positive as the ratio rr passes through rcritr_{crit} increasingly. In the massive case, we find the pressure tends to the result of massless field when the mass approaches zero. Furthermore, there is another critical ratio of the lengths rcritr_{crit}^{\prime} and the pressure is independent of the mass at r=rcritr=r_{crit}^{\prime} in the D=3 case.Comment: 11 pages, 3 figures, to be published in Mod. Phys. Lett.
    corecore