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As a new generation of Al-Zn-Mg-Cu alloy, 7085 Al alloy was first evaluated by high-cycle fatigue (HCF) tests. In the present work, HCF behaviors and the notch sensitivity of a 220-mm-thick 7085-T74 Al alloy ultra-thick plate were investigated. The fracture characteristics of the alloy were investigated, and the crack initiation mode of the alloy was proposed in the present study. The results show that the notch-sensitive coefficient is 0.367, which indicates that the 7085 Al alloy displays a sensitive notch effect. The fatigue crack initiation sites of 7085-T7452 Al alloy ultra-thick plate mainly occurred at the locations of coarse Fe-rich particles on the specimen surface. In addition, compared with smooth specimens, the notched specimens are prone to generating fatigue cracks and usually show more than one crack initiation site. [ABSTRACT FROM AUTHOR]

Candida shehatae gene xyl1 and Pichia stipitis gene xyl2, encoding xylose reductase (XR) and xylitol dehydrogenase (XD) respectively, were amplified by PCR. The genes xyl1 and xyl2 were placed under the control of promoter GAL in vector pYES2 to construct the recombinant expression vector pYES2-P12. Subsequently the vector pYES2-P12 was transformed into S. cerevisiae YS58 by LiAc to produce the recombinant yeast YS58-12. The alcoholic ferment indicated that the recombinant yeast YS58-12 could convert xylose to ethanol with the xylose consumption rate of 81.3%. [ABSTRACT FROM AUTHOR]

CdS nanoparticles with good crystallinity were prepared by hydrothermal method in microemulsion composed of polyoxyethylene laurylether/water/cyclohexane/butanol. The structure and the size of the CdS nanoparticles were analyzed by TEM and XRD. The UV-Vis optical absorption of the samples was also investigated. The results show that hydrothermal treatment is an effective method to prepare CdS nanoparticles of hexagonal structure at lower temperature. The particles were in dimensional uniformity. The diameter of the CdS nanoparticles decreased with the increase of the molar ratio of water to surfactant. The minimum diameter of the CdS nanoparticles prepared in this work was about 10 nm. Obvious blue shift appeared in the UV-Vis absorption spectra. [ABSTRACT FROM AUTHOR]