Galvanostatic anodization of aluminum at high current densities ͑100, 150, 200 mA cm Ϫ2 ͒ was studied. The growth rates of the synthesized anodic aluminum films were 1-3 m/min. Films with ordered pores or with a fractal surface were also prepared. Consequently, nonlinear anodization and hypothesis for film formation are proposed and applied to elucidate experimental results. Transmission electron microscopy ͑TEM͒ and scanning Auger electron microscopy ͑SAM͒ were applied to acquire supplementary experimental results to support the proposed hypothesis. TEM shows that initial oxygen bubbles were collected on the boundary of neighboring hexagonal cells, channels for bubble liberation were located in the center of hexagonal cells. By profiling on SAM, depth profiles of Al and O atoms in the film were obtained, and the assumption that oxygen evolution plays positive roles in ion transfer during anodizing was supported indirectly. Although the validity of the hypothesis needs further testing, some points of the assumption are supported.

This study investigated estrogenic activity of water, sediment, and fish bile of the Pearl River in southern China by effect-directed analysis based on in vitro yeast screen assay and chemical analysis. Results showed higher estradiol equivalents (EEQ) for surface water in dry season than in wet season. Simple risk assessment suggested that high estrogenic risk would be expected in Shima River and Danshui River receiving discharge of effluents from cities in the region. Fractionation and effect-directed analysis showed that estrogenic activity mainly occurred in relatively polar fractions of surface water. Seven target estrogenic compounds (bisphenol A, 4-nonylphenol, 4-tert-octylphenol, 17α-ethynyl estradiol, estrone, diethylstilbestrol, and 17β-estradiol) only accounted for part of the measured estrogenic activity, with the rest contributions from other potential estrogenic chemicals such as phenols. Findings from this study suggest that fish in the river could be affected by those estrogenic chemicals. Proper measures should be taken to reduce the estrogenic activity in wastewaters before they are discharged into the riverine system in order to protect aquatic organisms.

Friction stir welding(FSW) as a new，environmental and energy-saving solid phase joining technology has become the focus of research in the welding field at home and abroad in recent years. The technical characteristics，microstructure and application status of Friction Stir Welding were elaborated in this paper，meanwhile the studying situation of Friction stir welding for aluminium alloys, magnesium alloys and so on was stated. Finally development prospect of FSW in welding field was analyzed.

In recent years, the development of digital libraries also encountered a lot of problems, the cloud computing was applied to digital libraries can solve the problem of information on demand and optimal scheduling of resources and transaction processing capabilities effectively, So as to achieve the purpose of improving the efficiency of resource of digital library and information security. From the digital library of cloud computing and personalized information services status in this paper, the study and found a problem about the digital library information services at this stage, let the virtualization cloud computing, the key technology of distributed data storage, massive data processing and cloud platforms used in building digital library of personalized information service with cloud platform, and deployment cloud services on the platform.