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We have investigated microstructure and orientation relationship (OR) of the?and?phases in an as-cast ingot and nodular bainite of Cu-14.9 at.% Sn alloy by using transmission electron microscopy. Proeutectoid?grains and surrounding?phase (prior?phase) possess well-defined (1?1?1)?//(1?1?0)?,OR, that is, Kurdjumov–Sach (K–S) OR, while these two phases formed by eutectoid decomposition exhibit some deviation from K–S OR. On the other hand, the?and?phases in nodular bainite exhibit (1?1?1)?//(1?1?0)?,, which is Nishiyama–Wassermann (N–W) OR, as well as K–S OR. The emergence and variations of these ORs between the?and?phases have been interpreted from the viewpoints of (i) matching of interplanar spacing of {1?1?1}?, {1?1?0}?and {6?6?0}?planes, (ii) minimum strain criteria based on the invariant line concept for K–S OR and (iii) correspondence of atomic positions in the relevant phases by employing the structural ledge concept for N–W OR. [ABSTRACT FROM AUTHOR]

Discontinuous precipitation (DP) in Cu–8.6 at% Sn alloy at 573 K has been studied using transmission electron microscopy and electron back scattered diffraction techniques. DP reactions occur only sporadically at grain boundaries after prolonged aging, giving rise to a cellular morphology. The supersaturatedα′phase (face-centred cubic) phase decomposes not into the equilibriumαandεphases as reported to date, but into theαandζ(space groupP63,a = 0.733,c = 0.786 nm) phases, the latter being stable above 835 K. These two phases possess the following orientation relationship (OR):. Well-defined habit planes do not exist. However, broad faces ofζlamellae are often parallel to the {}ζplane. The observed OR and cellular morphology have been interpreted by matching atomic rows across the phase boundaries in two perpendicular directions. Namely, the spacings of (110)αand (0001)ζplanes, which match across the broad faces of theζlamellae, are nearly the same, while, in a perpendicular direction, mismatch between (111)αandspacings amounts to 0.5%. The facing (111)αandplanes form a coincidence site lattice, and atomic configurations in these planes both contain similar triangular atomic networks. It was also found that the orientation of the depletedαphase is often correlated with that of the adjoiningα′grain. This correlation indicated that the OR hold successively uponα′ → ζ → αtransformation. Possible orientations of theαphase have been enumerated, as supervariants to the adjoiningα′grains mediated by theζphase. [ABSTRACT FROM AUTHOR]

Objective: To investigate the menstruation status of reproductive age women of Han Nationality in Liaoning province., Methods: From Apr. 2008 to Dec. 2008, 1611 women at age of 19-45 years from Shenyang, Yingkou, Benxi, Zhangwu were enrolled in this study according to epidemiologic cluster sampling method. The study was performed by questionnaire consisting of age of menarche, regularity of menstruation, menstrual cycle and dysmenorrhea, et al., Results: In the survey of 1611 women, the average menarche age is 14.4 years old, there were significant difference on menarche between (14.2 +/- 1.5) years in women from city and (14.6 +/- 1.5) years in women from country (t = 6.58, P < 0.01). The linear regression statistic method was used to analyze the relationship between age and menarche age, the linear regression equation was gotten as Y = 0.074X + 11.855, which means 1 year increase was associated with decrease by 0.074 years in menarche age approximately. About 86.34% (1391/1611) of women have normal and regular menstrual cycle at range of 21 to 35 days, while 11.05% (178/1611) of women have longer menstrual cycle (> 35 days) and 2.61% (42/1611) of women have shorter menstrual cycle (< 21 days). Of which 65.67% (1058/1611) women have regular menstrual cycle just after menarche, 94.97% (1530/1611) of women would have regular menstruation in 2 years after menarche. The rate of dysmenorrhea was 42.09% (678/1611), of which 13.6% (92/678) women have high severe pelvic pain., Conclusion: Our results suggested that the trend went toward younger ages of menarche, which was younger menarche age in women from city than country. About 95% women would have regular menstrual cycle within 2 years after menarche.