The effect of antioxidant extracted from bamboo leaves (AOB) on the quality of sturgeon fillets during chilled storage was examined via three parameters: total volatile basic nitrogen (TVB-N), pH and bacterial community composition. The samples treated with 0.05% (w/v) AOB exhibited the best quality, as evidenced by retarding both pH changes and the production of TVB-N. Pseudomonas and Aeromonas were the dominant indigenous bacteria present in fresh sturgeon fillets, whereas the presence of Janthinobacterium and Pedobacter increased gradually throughout the storage process. A significant (P < 0.05) positive correlation was observed between the pH, TVB-N and two bacterial groups, Pseudomonas and Pedobacter. Based on the TVB-N assessment, the fillets began to decompose at the ninth day in the control samples and the twelfth day in the 0.05% AOB-treated samples. The relative abundance of Pseudomonas, Janthinobacterium and Pedobacter in the 0.05% AOB treatment group was lower than in the control group. Therefore, our results showed that treatment with 0.05% AOB improved the quality of fillets during the box-packaged storage.

A new GaAs/InGaAs triangular barrier optoelectronic switch combined with tri-state characteristic is fabricated and demonstrated. Two GaAs/InGaAs barriers are employed to provide potential barriers for electron thermionic emission and hole confinement, respectively. Applying a sufficient DC voltage to this device, a double S-shaped negative differential resistance (NDR) phenomenon with nearly equal switching voltage difference is appeared at room temperature. This unique NDR property can be introduced to triple stable regions into the device circuit design. Based on a proper circuit design with suitable load line, the studied device has potential for triple-logic applications.

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Al-6wt.%Si-3.5wt.%Cu alloy (A319) were prepared by casting and powder metallurgy (PM) methods to investigate the influence of processing procedure on properties. The casting samples were cast into a horizontal mold after degassing by argon. The PM samples were extruded after hot-press sintering before which Al-11wt.%Si master alloy powder, pure Al powder and 48 h ball-milled Al-40wt.%Cu powder were blended for 12 h at rotation speed of 250rpm. The samples underwent a T6 temper, i.e. solution, water quenching and artificial aging. Microstructures were observed by optical microscope (OM) and scanning electron microscope (SEM), and phases were determined by X-ray diffraction (XRD). The tensile testing was carried out on universal testing machine. The results showed that heat treatment could greatly improve the tensile strength of the samples, especially for the casting counterpart. Discussion was made to analyze the reason that the properties differed.