The effect of Ce on inclusions and impact toughness of 2Cr13 stainless steel were studied by SEM and electron spectroscopy. Thermodynamic calculation was used to analyze the formation of RE inclusions in 2Cr13 stainle...The effect of Ce on inclusions and impact toughness of 2Cr13 stainless steel were studied by SEM and electron spectroscopy. Thermodynamic calculation was used to analyze the formation of RE inclusions in 2Cr13 stainless steel. The result shows that Al2 O3 and MnS can be entirely replaced by Ce2 O2 S and CeS. Fracture is changed from cleavage to ductile fracture by adding Ce to the 2Cr13 stainless steel, and the spherical rare earth oxysulfide inclusions （Ce2 O2 S） in the dimple are the main factors. The transverse impact value of 2Cr13 stainless steel has been improved obviously by Ce. The transverse impact value of RE-2Cr13 is increased by 54.55% at the temperature of --40℃, comparing with 0RE-2Cr13.展开更多
Two topological information indices were constructed based on Randic and Wiener indices, and the values of topological information indices for 85 alkanes were calculated. The thermodyndric properties such as the stand...Two topological information indices were constructed based on Randic and Wiener indices, and the values of topological information indices for 85 alkanes were calculated. The thermodyndric properties such as the standard enthalpies of formation, the standard entropies and the standard free energies of formation for these alkanes were also correlated with these topological and information indices. It is found that the thermodynamic properties calculated for both gaseous and liquid states of the 85 alkanes are in excellent agreement with the experimental values through the regression analysis.展开更多
基金Item Sponsored by National Natural Science Foundation of China(50364001)
文摘The effect of Ce on inclusions and impact toughness of 2Cr13 stainless steel were studied by SEM and electron spectroscopy. Thermodynamic calculation was used to analyze the formation of RE inclusions in 2Cr13 stainless steel. The result shows that Al2 O3 and MnS can be entirely replaced by Ce2 O2 S and CeS. Fracture is changed from cleavage to ductile fracture by adding Ce to the 2Cr13 stainless steel, and the spherical rare earth oxysulfide inclusions （Ce2 O2 S） in the dimple are the main factors. The transverse impact value of 2Cr13 stainless steel has been improved obviously by Ce. The transverse impact value of RE-2Cr13 is increased by 54.55% at the temperature of --40℃, comparing with 0RE-2Cr13.
文摘Two topological information indices were constructed based on Randic and Wiener indices, and the values of topological information indices for 85 alkanes were calculated. The thermodyndric properties such as the standard enthalpies of formation, the standard entropies and the standard free energies of formation for these alkanes were also correlated with these topological and information indices. It is found that the thermodynamic properties calculated for both gaseous and liquid states of the 85 alkanes are in excellent agreement with the experimental values through the regression analysis.
