2,888 research outputs found
Quark Condensates in Nuclear Matter in the Global Color Symmetry Model of QCD
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 12) 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
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)
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)
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
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
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
()-dimensional spacetime.
We obtain the exact results of the Casimir energy density and pressure for
any 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 of
the ratio of the lengths at which the pressure vanishes. The pressure
changes from negative to positive as the ratio passes through
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 and the pressure is
independent of the mass at in the D=3 case.Comment: 11 pages, 3 figures, to be published in Mod. Phys. Lett.
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