The effects of Zr on crystallization kinetics of Pr Fe B amorphous alloys have been investigated by DTA and XRD methods. It was found that for Pr 8Fe 86- x Zr x B 6 ( x =0, 1, 2) amorphous alloys, the final crystalliz...The effects of Zr on crystallization kinetics of Pr Fe B amorphous alloys have been investigated by DTA and XRD methods. It was found that for Pr 8Fe 86- x Zr x B 6 ( x =0, 1, 2) amorphous alloys, the final crystallized mixture is α Fe and Pr 2Fe 14 B, and the metastable Pr 2Fe 23 B 3 phase occurs during crystallization of Pr 8Fe 86 B 6 amorphous alloy, not during crystallization of Pr 8Fe 86- x Zr x B 6( x =1, 2) amorphous alloys. By analyzing the activation energy of crystallization, the formation of an α Fe/Pr 2Fe 14 B composite microstructure with a coarse grain size in annealed Pr 8Fe 86 B 6 alloy, is attributed to a difficult nucleation and an easy growth for both the α Fe and Pr 2Fe 14 B in the alloy. The addition of Zr can be used to change the crystallization behavior of the α Fe phase in Pr Fe B amorphous alloy, which is helpful to reduce the grain size for the α Fe phase.展开更多
AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T a...AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T and G1764A) mutant viruses and serum levels of hepatitis B virus(HBV) DNA, hepatitis B surface antigen(HBs Ag), and HB core-related antigen were analyzed in chronic hepatitis B patients before and after HBe Ag seroconversion(n = 25), in those who were persistently HBe Ag positive(n = 18), and in those who were persistently anti-HBe positive(n = 43). All patients were infected with HBV genotype C and were followed for a median of 9 years.RESULTS: Although the pre-core mutant became predominant(24% to 65%, P = 0.022) in the HBe Ag seroconversion group during follow-up, the proportion of the basal core promoter mutation did not change. Median HBV viral markers were significantly higher in patients without the mutations in an HBe Ag positive status(HBV DNA: P = 0.003; HBs Ag: P < 0.001; HB core-related antigen: P = 0.001). In contrast, HBV DNA(P = 0.012) and HBs Ag(P = 0.041) levels were significantly higher in patients with the pre-core mutation in an anti-HBe positive status.CONCLUSION: There is an opposite association of the pre-core mutation with viral load before and after HBe Ag seroconversion in patients with HBV infection.展开更多
文摘The effects of Zr on crystallization kinetics of Pr Fe B amorphous alloys have been investigated by DTA and XRD methods. It was found that for Pr 8Fe 86- x Zr x B 6 ( x =0, 1, 2) amorphous alloys, the final crystallized mixture is α Fe and Pr 2Fe 14 B, and the metastable Pr 2Fe 23 B 3 phase occurs during crystallization of Pr 8Fe 86 B 6 amorphous alloy, not during crystallization of Pr 8Fe 86- x Zr x B 6( x =1, 2) amorphous alloys. By analyzing the activation energy of crystallization, the formation of an α Fe/Pr 2Fe 14 B composite microstructure with a coarse grain size in annealed Pr 8Fe 86 B 6 alloy, is attributed to a difficult nucleation and an easy growth for both the α Fe and Pr 2Fe 14 B in the alloy. The addition of Zr can be used to change the crystallization behavior of the α Fe phase in Pr Fe B amorphous alloy, which is helpful to reduce the grain size for the α Fe phase.
基金Supported by Research grant from the Ministry of Health,Labor,and Welfare of Japan
文摘AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T and G1764A) mutant viruses and serum levels of hepatitis B virus(HBV) DNA, hepatitis B surface antigen(HBs Ag), and HB core-related antigen were analyzed in chronic hepatitis B patients before and after HBe Ag seroconversion(n = 25), in those who were persistently HBe Ag positive(n = 18), and in those who were persistently anti-HBe positive(n = 43). All patients were infected with HBV genotype C and were followed for a median of 9 years.RESULTS: Although the pre-core mutant became predominant(24% to 65%, P = 0.022) in the HBe Ag seroconversion group during follow-up, the proportion of the basal core promoter mutation did not change. Median HBV viral markers were significantly higher in patients without the mutations in an HBe Ag positive status(HBV DNA: P = 0.003; HBs Ag: P < 0.001; HB core-related antigen: P = 0.001). In contrast, HBV DNA(P = 0.012) and HBs Ag(P = 0.041) levels were significantly higher in patients with the pre-core mutation in an anti-HBe positive status.CONCLUSION: There is an opposite association of the pre-core mutation with viral load before and after HBe Ag seroconversion in patients with HBV infection.