Strain ST22 and SX10 isolated from the twigs of Ginkgo biloba L. were found to be able to produce phenolic and flavonoid compounds. They were systematically identified by both morphological and molecular methods. Morphological identification, which employed light microscope and scanning electron microscope, showed that ST22 and SX10 are members of Aspergillus. ITS1-5.8S-ITS2 regions of these two strains were cloned in order to carry out a similarity alignment. ST22 was identified as Aspergillus nidulans and SX10 as Aspergillus oryzae. In addition, the total phenolic and flavonoid contents were measured via UV-spectrophotometry. The total phenolic contents in ST22 and SX10 were 0.1413±0.0098 and 0.1450±0.0154 mg/ml, respectively. The amounts of total flavonoids in ST22 and SX10 were 0.01162±0.0014 and 0.01256±0.00378 mg/ml, respectively. It was concluded that these two strains may have potential as sources of natural medicines or prodrugs.

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In this study, the process of explosive welding of Mg/Al plate is represented, and the interfacial behavior of two metals is researched. The objective of this work is to investigate the factors that affect the quality of explosive bonding and the distribution of physical parameters on the collision. A finite difference engineering package with smoothed particle hydrodynamics method is used to model the oblique impact of a thin flyer plate (Al) on a relatively thick base plate (Mg). Wavy interface and jetting phenomenon, which existed in the experiment, are well reproduced in the simulation. The contours of pressure, shear stress, velocity, and effective plastic strain of magnesium and aluminum are also distinctly described. The bonding turns out to be a possible solid-state welding process. The effective plastic strain exceeds a minimum value, and the shear stress is just the opposite sign in this simulation where available bonding occurred. Wave formation appears to be the result of variation in the velocity distribution on the interface and periodic disturbances of magnesium and aluminum. A transition from straight to wave occurs along the interface. High values of plastic strain of two metals are predicted on the interface.