In this paper, taking Nb-Mo alloy system as an example, the equations of concentration of characteristic atoms of alloys in BCC structure were obtained on the basis of the idea of systematic science of alloys and the number of coordination atoms. The concentrations of characteristic atoms in B2-NbMo type ordered alloys were calculated as functions of ordering degree（s） and composition Xuo. When S=Smax, the concentrations of characteristic atoms of stoichiometric B2-NbMo intermetallic compound are equal to that of alloys, that is, X8^Nb = 0.5 at, X0^Mo= 0.5 at. As ordering degree decreases, characteristic atoms A8^Nb and A0^Mo of B2-NbMo type ordered alloy split. And the degree of splitting of characteristic atoms increases with the ordering degree decreasing. Therefore, disordered alloys and various types of ordered alloys can be designed.
合成一种新型寡聚噻吩类有机小分子2,5-二[5-(4′-辛基-[2,2′-二噻吩]-5-基)-3-己基-1,3,4-噁二唑-2-硫酮]噻吩(DHOT),并将其应用于太阳能电池中。研究结果表明:DHOT具有较好的热稳定性、良好的溶解性能和成膜性能;在薄膜状态下,DHOT的吸收光谱范围为300~600 nm,其最大吸收峰在425 nm处,相应的光学带隙为2.17 e V;用DHOT组装太阳能电池,其结构为ITO/PEDOT:PSS/DHOT:PC71BM/Zr Acac/Al;当DHOT与PC71BM质量比为1:1时,其能量转换效率为1.03%,对应的开路电压为0.84 V,短路电流密度为3.99 m A/cm2,填充因子为30.7%。
Taking Ta–W alloy system as an example, the concentration formulae of alloy genes of DO3-type alloys in BCC structures were derived on the basis of the theory of alloy genes and the number of coordination atoms. The concentrations of alloy genes of DO3-TaW3 and DO3-Ta3W ordered alloys were calculated as functions of composition xW and ordering degree （s）. When s=smax, the concentrations of alloy genes of stoichiometric DO3-TaW3 compound are equal to those of alloys, that is, x8^Ta=0.25（at）,x4^W=0.5（at）,x8^W=0.25（at）The concentrations of alloy genes of stoichiometric DO3-Ta3W compound are also equal to those of alloys, that is,x0^Ta=0.25（at）,x4^Ta=0.5（at）,x0^W=0.25（at）. As ordering degree decreases, alloy genes of DO3-TaW3 and DO3-Ta3W ordered alloys will split. And the degree of splitting of alloy genes increases with the ordering degree decreasing. The atomic states and properties of DO3-TaW3 and DO3-Ta3W ordered alloys were calculated as a function of composition xW. The reason was pointed out that preparation of DO3-TaW3 and DO3-Ta3W intermetallic compounds is difficult due to small differences in their cohesive energies. It will provide theoretical guidance for the scientific designation to new candidate for ultra- high-temperature materials in areo-engine applications.
Isometric heat capacity cv and isobar heat capacity cp of Ru metal in HCP,FCC,BCC and liquid state were calculated by using pure element systematic theory.The results are in good agreement with joint army-navy-air force(JANAF) experimental value and the calculation result by first-principle(FP) method.But the results have great differences in contrast to Scientific Group Thermodata Europe(SGTE) database.The cause is found that it cannot neglect the electron devotion to heat capacity to adjust cp in one-atom(OA) method.The disparity between OA method and SGTE database was discussed.The main cause is that OA method adopts the crosspoint with iso-Ec-line and iso-a-line in hybritriangle to determine the properties,but SGTE database is obtained by extrapolation from activity measurements and critical assessment of data from a large number of binary system.Thermodynamic properties of Ru metal in HCP,FCC,BCC and liquid state,such as entropy S,enthalpy H and Gibbs energy G were calculated.Therefore,the full description of thermodynamic properties from 0 K to random temperature is implemented.
