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The mycotoxin ochratoxin A (OTA) is a common contaminant of various plant-derived foods and feeds. However, methods for complete decontamination remain to be established. Recently, biological approaches for mycotoxin removal using various species of yeast have been explored. In the present study, we investigated the efficacy of OTA degradation by the yeast Yarrowia lipolytica under various conditions, altering yeast concentration, temperature, pH, and concentration of OTA in order to determine the optimal requirements of this species. At a yeast concentration of 108 cells/ml, the degradation rate was higher than that observed at any other concentration and, after 24 h, the OTA concentration was reduced to almost half of the initial level introduced to the culture. Further, Y. lipolytica cultured at 28 °C showed the highest level of OTA degradation. Similarly, the culture performed optimally at a pH of 4. The initial concentration of OTA also affected the ability of the yeast to degrade OTA, with the level of degradation being the highest when the initial OTA concentration was 0.1 μg/ml. Moreover, we also tested the toxicity of the OTA biodegradation products using HepG2 cells to determine the physiological applicability of this yeast species in the food industry and observed that these products were notably less toxic than non-degraded OTA. Y. lipolytica effectively reduced natural decay incidence of grapes, and had no negative effect to the storage quality of grape fruits. Taken together, these data suggest that Y. lipolytica could be a viable OTA contamination prevention/treatment option and additional research concerning its commercial use is warranted.

Under the condition of different magnetic induced intensity as1.5T, 2.0T and2.5T, AlTiZr particles reinforced 7055 aluminum matrix composites were subject to the magnetic impact processing. The structural evolution was observed by transmission electron microscope. The result shows that, magnetic impact processing can induce dislocation with different morphologies and increase the dislocation density. The enhancement of dislocation density and elastic interaction between them can cause the resistance of dislocation movement and improve the strength of material. The magnetic pressure may exceed the yield strength of special orientation crystal. The increased temperature induced by heat effect will lower the yield point further. It is useful to dislocation nucleation and movement.

new flux method is explored to decrease the reactive temperature of in situ chemical reaction to fabricate particles reinforced aluminum matrix composites. When B2O3 flux is added into the mixed reactive salts the melting points of them decrease with the increase of adding amount of B2O3 in the range of 1-5wt.%. When w(B2O3)=5% the melting point of K2TiF6-B2O3 salt is 450°C,which is decreased by 90°C compared with that of pure K2TiF6. Meanwhile the in situ reactive time is shortened and the actual volume fraction is increased.

Al2O3，Al3Ti and Al3Zr particles reinforced 7055 aluminium matrix composites were fabricated via melt reaction method. The volume fraction is controlled at about 4-5%. After extrusion and solution-aging heat treatment the sample was prepared for deep cryogenic treatment, The microstructure and evolution of mechanical properties of (Al3Ti+Al3Zr)p/7055 composites were analyzed using optical microscopy(OM),scanning electronic microscopy(SEM) and X-ray diffraction(XRD). Some θ(Al2Cu) phases with nanometer size precipitate in the inner grain. As some grains preferred orient the intensity of some main diffraction peaks increase. Compared with those of as-cast and squeezed states the micro hardness has increased by 16.8% and 10.0% separately.

B2O3 is used as fluxing agent of converter slag to substitute for CaF2 so as to reduce fluorine pollution and decrease the melting temperature. Hemisphere method is used to measure the melting temperature of samples. Effect of ω(CaO)/ω(SiO2), content of Fe2O3 and content of B2O3(CaF2) on the melting temperature of CaO-SiO2-F2O3-B2O3(CaF2) system have been studied. Results indicate that the melting temperature of samples are decreased when B2O3 substitute for CaF2 equally with equal ω(CaO)/ω(SiO2) and content of Fe2O3 [ω(CaO)/ω(SiO2)=1.5~5.0, Fe2O3=0~30%], the melting temperature of samples are decreased remarkably with the increase of content of B2O3 [ω(CaO)/ω(SiO2)= 2.5].

The K2TiF6,K2ZrF6powder and aluminum were selected as the raw materials to in situ synthesize the particulates reinforced aluminum matrix composites. During the fabrication process the electromagnetic field was imposed. The atomic ratio of Al/Ti/Zr in the particulates is determined as 3/0.4/0.6. The Al3Ti0.4Zr0.6is a new kind of intermetallic compound, some properties of which fall in between those of Al3Ti and Al3Zr. Electromagnetic field plays an important part in fining particles and promoting their uniform distribution. When the electromagnetic induced intensity is 0.05T the particles have 0.5-2μm average size and uniform distribution in matrix. The crystal grains of matrix resemble equiaxed ones. The average size of grains are nearly 100μm, 50μm and 25μm when the electromagnetic induced intensities are 0, 0.025T and 0.05T seperately.