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Density functional calculations have been performed for the structural, electronic, and magnetic properties of Au5M (M = Sc-Zn) clusters. Geometry optimizations indicate that the M atoms in low-energy Au5M isomers prefer to occupy the most highly coordinated position. The ground-state clusters except Au5Sc possess a planar structure. The vibrational spectra of the doped clusters are completely different from that of a pure gold cluster. The relative stability and chemical activity are investigated through the averaged binding energy and energy gap for the most stable Au5M clusters. It is found that the impurity atoms (not including the Zn atom) can enhance the thermal stability of the host cluster. The chemical activity of Au5M clusters is higher than that of the Au6 cluster. The calculated energy gaps are in accord with available approximate experimental data. The vertical ionization potential, the electron affinity, and photoelectron spectrum are computed and simulated theoretically for all of the ground-state clusters. The magnetism analyses show that the magnetic moment of these Au5M clusters varies from 0 to 5 μB by substituting a Au atom in a Au6 cluster with various M atoms and is mainly localized on the M atom for M = Ti-Ni.

The possible geometrical and electronic structures of small Pd-Y clusters including Pd n （n=2,3,4）,Y n （n=2,3,4）, PdY n （n=2,3, 4）, Pd n Y(n=1,2,3,4) and Pd 2 Y n （n=2,3,4） have been optimized by density functional theory method with a relativistic effective core potentia l(RECP) using Gaussian 98 code. Due to the Jahn-Teller effect, the ground states of Pd 4 and Y 4 belong to C s , while the symmetry is C 2v for P d 3 and Y 3 . The ground states of Pd 3 Y, Pd 4 Y, PdY 3 ,PdY 4 and Pd 2 Y 4 b elong to C s . Finally, the energy level distribution, highest occupied mole cular orbit-lowest unoccupied molecular orbit gaps and the chemical activation a re investigated.

Object-oriented Petri Net modeling of coal supply chain system can be established from the perspective of workflow by applying the technology of object-orientation and Petri net. On the basis of the modeling, profit maximization optimization for the selection of resources and the environment in a certain condition to meet customer demand is taken as the coal supply chain optimization objective. And under the quantitative description and analysis of the internal nodes, logistics, capital flow and information flow in coal supply chain system, the optimal method is used for objective optimization. Through this research, we have learned that the use of the method in coal supply chain modeling and objective optimization can accurately reflect the operation of the coal supply chain and its resource constraints, which will finally improve decision-making performance. The complex systems can be highly abstracted by using this OPN model which is also easy for expansion and optimization model has a strong versatility.