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Structural and electronic properties of Pb n Ag n (n=2–12) clusters were investigated by density functional theory with generalized gradient approximation at BLYP level in DMol3 program package. The optimized bimetallic Pb n Ag n (n=2–12) clusters were viewed as the initial structures, then, those were calculated by ab initio molecular dynamics (AIMD) to search possible global minimum energy structures of Pb n Ag n clusters, finally, the ground state structures of Pb n Ag n (n=2–12) clusters were achieved. According to the structural evolution of lowest energy structures, Ag atoms prefer gather in the central sites while Pb atoms prefer external positions in Pb n Ag n (n=2–12) clusters, which is in excellent agreement with experimental results from literature and the application in metallurgy. The average binding energies, HOMO-LUMO gaps, vertical ionization potentials, vertical electron affinities, chemical hardness η, HOMO orbits, LUMO orbits and density of states of Pb n Ag n (n=2–12) clusters were calculated. The results indicate that the values of HOMO-LUMO gaps, vertical ionization potentials, vertical electron affinities and chemical hardness η show obvious odd-even oscillations when n≤5, Pb n Ag n (n=2–12) clusters become less chemically stable and show insulator-to-metal transition with the variation of cluster size n, Pb n Ag n (n≥9) cluster are good candidates to study the properties of PbAg alloys. Those can be well explained by the density of states (DOS) distributions of Pb atoms and Ag atoms between–0.5 Ha and 0.25 Ha in Pb n Ag n (n=2–12) clusters.

The structural, relative stable and electronic properties of PbnSnn (n = 2–12) alloy clusters were systematically studied using density functional theory. The isomers of PbnSnn alloy clusters were generated and determined by ab initio molecular dynamics. By comparing the calculated parameters of Pb2 dimer and Sn2 dimers with the parameters from experiments, our calculations are reasonable. With the lowest-energy structures for PbnSnn clusters, the average binding energies, fragmentation energies, second- order energy differences, vertical ionization potentials, vertical electron affinities, HOMO–LUMO gaps, and density of states were calculated and analyzed. The results indicate that the Sn atoms have a tendency to bond together, the average binding energies tend to be stable up to n = 8, Pb8Sn8 cluster is a good candidate to calculate the molecular interaction energy parameter in Wilson equation, the clusters become less chemical stable and show an insulator-to-metallic transition, 3, 6, 8 and 11 are magic numbers of PbnSnn (n = 2–12) clusters, the charges always transfer from Sn atoms to Pb atoms in PbnSnn clusters except for Pb10Sn10 cluster, and density of states of PbnSnn clusters becoming continuous and shifting toward negative with the increasing size n.

In order to investigate the structural and electronic properties of bimetallic Pb n Cu n (n = 2–14) clusters, density functional theory (DFT) were applied. The ground-state structures, average bond distances, binding energies, Mulliken population analysis, vertical ionization potentials, vertical electron affinities, HOMO-LOMO gaps and electronic density of states of Pb n Cu n (n = 2–14) bimetallic clusters were calculated by DFT, The results show that Cu atoms gathering together and encapsulated by peripheral Pb atoms. In addition, the charges always transfer from Pb atoms to Cu atoms, the metallicity of Pb n Cu n clusters increase with the increasing size n, the trend of VIPs is contrary to the trend of VEAs, 4, 8 and 11 are the magic numbers of Pb n Cu n clusters, s-p hybrizations play a crucial role in Pb n Cu n clusters.

The formula for jamesonite is Pb 4 FeSb 6 S 14 (or 4PbS·FeS·3Sb 2 S 3 ). This paper proposes a novel method for the separation and enrichment of PbS and Sb 2 S 3 from jamesonite by vacuum distillation. The experiments were carried out at temperatures ranging from 1073 K to 1473 K and at pressures less than 10,000 Pa. The amount of Sb, Pb, and Fe in the volatiles and residues was determined by chemical titration analysis and the enrichment ratios of Sb, Pb, and Fe were calculated. We discuss the influence of the distillation temperature and holding time on the enrichment ratios of each element. The results of the XRD and EDS analyses of the residues and volatiles indicates that FeS remains in the residues as the major compound, Sb exists in the form of Sb 2 S 3 , and Pb exists in the form of PbS in different condensers. Experimental results showed that Sb 2 S 3 condensed at about 725 K PbS condensed at about 984 K in different condenser.

AlN chlorination route, in the present work, was proposed to extract Aluminum from aluminum nitride under vacuum. Density functional theory (DFT) were implemented to study the interaction of AlCl 3 molecule and AlN ( 10 1 ¯ 0 ) surface. The results of DFT indicate that chemisorbed AlCl 3 adsorption configuration was observed on the clean AlN ( 10 1 ¯ 0 ) surface after structure optimization, and adsorbed AlCl molecules were generated after 1 ps dynamic simulation time. The phase and composition of condensate were examined by means of XRD and EDS. It was found that 97.76 wt% of Al metal was obtained in the experiment B (in the presence of AlCl 3 ), however, no condensate was collected in the experiment A (without AlCl 3 ) at 1760 K under pressure of average 60 Pa. The results show that AlN chlorination route is an alternative Al production method from aluminum nitride.

In this research, thermodynamic analysis and CASTEP package of the Material Studio program which is based on density functional theory (DFT) formalism were used to study the carbothermic-chlorination (AlCl3) reaction of Al2O under vacuum. Thermodynamic calculations indicated that AlCl(g) can be generated by carbothermic-chlorination process at 1760K and 60Pa. The interaction of Al2O and AlCl3 with C showed that the chemical adsorption of Al2O and AlCl3 did take place on C(001) crystal plane, at the same time, new chemical bond have been formed between Al atom dissociated from Al2O and Cl atom dissociated from AlCl3 molecule. The result, after 1ps dynamics simulation, indicated that adsorbed AlCl and CO molecules have been generated in Al2O-AlCl3-C system, and they would escape from C surface after a longer period of dynamics simulation time. It means that the reaction of Al2O and AlCl3 with C can be carried out under given constraint condition.

This study was aimed to investigate the expression levels of CXCR4 and VEGF in serum of patients with DLBCL and their clinical significances. The peripheral blood of 44 patients with newly diagnosed DLBCL and 20 healthy adults as a control group were chosen for study. And the expression levels of CXCR4 and VEGF in serum were detected by ELISA. The results showed that the expressions of VEGF and CXCR4 in DLBCL patients were higher than those in the control group (P0.05). The expression of VEGF was positively correlated with the expression of CXCR4 in DLBCL patients, and the correlation coefficient was 0.743 (P0.05). The VEGF expression in DLBCL patients was correlated with LDH, immunotyping, the number of extranodal involvements, Ann Arbor staging and ECOG performance score; while the expression of CXCR4 was correlated with LDH, immunotyping, the number of extranodal involvements and Ann Arbor staging. Univariate analysis showed that LDH, extranodal involvements, immunotyping, Ann Arbor staging, CXCR4 and VEGF were associated with OS. Multivariate analysis showed that the immunotyping and CXCR4 expression independently associated with OS. It is concluded that both expression levels of VEGF and CXCR4 are significant higher than those in the control group. CXCR4 expression positively correlates with VEGF expression and displays a prognostic significance for OS. This study suggests that combined targeting VEGF and CXCR4 may become a novel therapeutic strategy for diffuse large B cell lymphoma.