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1

Minimizing total completion time for preemptive scheduling with release dates and deadline constraints

He C., Lin H., Lin Y., Dou J.

Foundations of Computing and Decision Sciences

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2014

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Vol. 39, No. 1

17--26

EN

It is known that the single machine preemptive scheduling problem of minimizing total completion time with release date and deadline constraints is NP-hard. Du and Leung solved some special cases by the generalized Baker's algorithm and the generalized Smith's algorithm in O(n2) time. In this paper we give an O(n2) algorithm for the special case where the processing times and deadlines are agreeable. Moreover, for the case where the processing times and deadlines are disagreeable, we present two properties which could enable us to reduce the range of the enumeration algorithm.

2

Synthesis, Characterization and Electrochemical Property of Dicyclohexyl-18-crown-6 Nickel(II) Bis(dithiolate) Complexes

Sun Y., Dong F., Dou J., Li D., Gao X., Wang D.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

2001-2009

EN

Two organic-inorganic hybrid dicyclohexyl-18-crown-6 nickel(II) bis(dithiolate) complexes, [K(DC18C6-B)]2[Ni(mnt)2] (1) and [K(DC18C6-A)]2[Ni(i-mnt)2] (2) (DC18C6-A = cis-syn-cis-dicyclohexyl-18-crown-6; DC18C6-B = cis-anti-cis-dicyclohexyl- 18-crown-6; mnt = maleonitriledithiolate; i-mnt = isomaleonitriledithiolate), have been synthesized by the reactions of dicyclohexyl-18-crown-6with NiCl2 andK2(mnt) or K2(i-mnt) respectively, and characterized by elemental analysis, FT-IR,UV-Vis spectroscopy and X-ray single crystal diffraction. They both crystallize triclinic, space group P1. Complex 1 shows a neutral molecule composed of two [K(DC18C6-B)]+ complex cations and one [Ni(mnt)2]2– complex anion via two K–N coordination bonds. In complex 2, the [K(DC18C6-A)]+ complex cation and [Ni(i-mnt)2]2– complex anion afford a 1D chain- like structure by N–K–N interactions.

3

Synthesis, characterization and Magnetic Studies of Oxamido-Bridged Copper(II)-Iron(III) Heterobinuclear Complexes

Li Y., Zhu C., Yan C., Dou J., Wang D.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 8

1265-1273

EN

Two new oxamido-bridged Cu(II)-Fe(III) heterobinuclear complexes of formulae [Cu(dmoxpn)Fe(bpy)2](ClO4)3 (1) and [Cu(dmoxae)Fe(bpy)2](ClO4)3 (2) have been synthesized, where bpy denotes 2,2_-bipyridine; while dmoxpn and dmoxae represent N,N_-bis[3-(dimethylamino)propyl]oxamido and N,N_-bis[2-(dimethylamino) ethyl]oxamido dianions, respectively. Based on elemental analyses, molar conductivity measurements, IR and electronic spectral studies, it is proposed that the two complexes have oxamido-bridged structures consisting of a copper(II) and an iron(III) ions, which have a square planar environment and a distorted octahedral environment, respectively. The two heterobinuclear complexes were further characterized by variable-temperature magnetic susceptibility (4.2~300 K) measurements and the observed data were simulated by the equation based on the spin Hamiltonian operator, H = JS S 1 2 2 , giving the exchange integral J = -18.2 cm-1 for (1) and J = -26.5 cm-1 for (2). The results revealed the occurrence of an intramolecular antiferromagnetic interaction between the adjacent iron(III) and copper(II) ions through the oxamido- -bridge within each molecule. The influence of the chelate ring arrangement around the copper( II) in the copper(II)-iron(III) heterobinuclear complexes on magnetic interactions between the metal ions of this kind of complexes is preliminarily discussed.

4

Synthesis and Magnetic Analysis of mi Oxamido-Bridged Cu(II)-Fe(II) Heterodinuclear Complexes

Li Y., Zhang G., Yan C., Dou J., Wang D.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 9

1405-1413

EN

The strategy of "complex as ligand" allowed us to synthesize two new mi-oxamido- bridged heterodinuclear complexes identified as [Cu(bmap)Fe(bpy)2]SO4 (1) and [Cu(bmap)Fe(phen)2]SO4 (2), where bmap represents the N,N'-bis(2-methyl-2-aminopropyl) oxamido dianion; bpy and phen stand for 2,2'-bipyridine and 1,10-phenanthroline, respectively. These complexes are the first examples of copper(II)-iron(II) species bridged by bmap groups. Based on elemental analyses, IR and electronic spectra studies, magnetic moments at room temperature and molar conductivity measurements, these complexes are proposed to have an extended oxamido-bridged structure consisting of planar copper(II) and octahedral iron(II) ions. The two heterodinuclear complexes have been further characterized by variable temperature magnetic susceptibility (4.2-300 K) and the observed data were least-squares fitted to the susceptibility equation derived from the spin Hamiltonian including single-ion zero-field interaction for the iron(II) ion,H=-2JS1 . S2-DS2 Z1 , giving the exchange integrals J = -18.9 cm-1 for (1) and J = -20.1 cm-1 for(2). These results indicated that the spin coupling between the adjacent copper(II) and iron(II) ions through the oxamido-bridge in both complexes (1) and (2) is antiferromagnetic. The influence of methyl substituents in the bridging ligand on magnetic interactions between the metal ions of this kind of complexes is also discussed