A detailed analysis of the structure of an 18-residue peptide C252A)] in 1,2-dimyristoyl-sn-glycero-phosphocholine bilayers was carried out using solid state NMR and attenuated total reflection Fourier transform infrared spectroscopy. The peptide corresponds to a portion of the 6th transmembrane domain of the α-factor receptor of Saccharomyces cerevisiae. Ten homologs of M6(252-269, C252A) were synthesized in which individual residues were labeled with 15 N. One-and two-dimensional solid state NMR experiments were used to determine the chemical shifts and 1 H-15 N dipolar coupling constants for the 15 N-labeled peptides in oriented dimyristoylphosphatidylcholine bilayers on stacked glass plates. These parameters were used to calculate the structure and orientation of M6(252-269, C252A) in the bilayers. The results indicate that the carboxyl terminal residues (9-14) are αhelical and oriented with an angle of about 8° with respect to the bilayer normal. Independently, an attenuated total reflection Fourier transform infrared spectroscopy analysis on M6(252-269, C252A) in a 1,2-dimyristoyl-sn-glycero-phosphocholine bilayer concluded that the helix tilt angle was about 12.5°. The results on the structure of M6(252-269, C252A) in bilayers are in good agreement with the structure determined in trifluoroethanol/water solutions (B. Arshava et al.

The effects of spheroidizing annealing process on SWRH72B heavily cold drawn pearlite steel wires were studied and the mechanisms of low-temperature spheroidizing annealing were discussed. The results show that, with increasing drawing strain, the spheroidizing annealing temperature and time decreased and uniformity of the spheroidizing increased; the mechanism of low-temperature spheroidizing annealing was different from the traditional one of heavily cold drawn pearlite steel wires. When the true strains were between 2.85 and 5.1, the spheroidizing process of carbide could be divided into two stages: partial dissolution of lamellar carbide, and the precipitation and accumulation of compulsory dissolved cementite. When the true strains were larger than 5.1, the spheroidizing process of carbide was only characterized by precipitation and accumulation of compulsory dissolved cementite.

This paper adopted the vacuum sintering technology to prepare titanium fiber porous material with a three-dimensional spatial network fiber backbone and connectivity pore structure. With the help of fractal geometry theory and scanning and digitizing the image, the fractal research of pore-structure in porous titanium fibers is executed and we studied the influence of adopting the box-counting dimension method to calculate the fractal dimension. Additionally, we determined the quantitative relationship between fractal dimension and the porosity of the porous in titanium fiber, while described the physical meaning of the fractal dimension.

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