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Light-flavour Baijiu is a type of Chinese liquor with a pure and mild flavour produced by traditional spontaneous solid-state fermentation. The flavour of this liquor has been found to vary in the different periods of annual production. To explore the factors affecting flavour, the microbiota of the surrounding environment, starter and fermentation process in different periods were investigated. Results showed that the ester content and acidity of light-flavour Baijiu were significantly lower when annual production was resumed after a summer break. HCA plot of volatile flavour profile and bacterial PCoA results indicated that the differences occurred at later stages, mainly due to different structures of Lactobacillus. Correlation analysis by O2PLS indicated that Lactobacillus positively correlated with esters. Species-level analysis showed that the lack of L. acetotolerans on the surface of the jar might cause a lag in fermentation and lower ester content. Thereafter, L. acetotolerans was revived during fermentation and enriched on the surface of the jar, which promoted ester formation. As important sources of L. acetotolerans, the air and fermentation jars played a critical role during fermentation. Therefore, this systematic study on environmental microbial ecology is valuable for quality control and to explore environmental microbiota functions during spontaneous fermentation.

Harmful low molecular weight substances in fifteen commercially available disposable cups were qualitatively analyzed. Contents of several suspected low molecular weight substances containing 2,6-Di-tert-butyl-4-methylphenol,Oleamide, Dibutyl phthalate in 15 disposable cups were quantitatively analyzed. The amount of igration of low molecular weight substances (DBP) in three food simulants was analyzed.

In this paper, nano TiO2 loaded on activated carbon fiber(ACF) was prepared by hydrothermal method as TiO2/ACF photocatalytic.The material crystal structure, the superficial appearance of catalyst, were analyzed and measured by XRD and SEM images.Moreover, it used for photocatalytic oxidation As(Ⅲ).The effect of pH on the oxidation of As(Ⅲ) was studied. The oxidation of As(Ⅲ) efficiency increasing markedly with pH, and the catalytic efficiency is much higher in the alkaline environment than in the acidic environment.

A polyurethane resin catalyst with the cross-linking silver (Ag) ion is successfully synthesized in this study, and its use as a catalyst in electroless copper deposition is also analyzed. FT-IR, SEM, EDX and electrochemical open circuit potential-time (OCP-t) technique are used to analyze the structure of the catalyst, the process of catalyzing copper deposition and induced rate of the electroless copper deposition. We also demonstrate that the polyurethane resin catalyst containing silver ion can be screen printed onto the PET substrate, then, a Cu pattern is successfully fabricated on the PET after electroless copper plating.

In this paper, the silicone rubber composed of carbon fibers was prepared. The influence of different concentration of carbon fibers on the conductivity, electromagnetic shielding interference effectiveness property of the silicone rubber was discussed from the point of view of condition of carbon fiber and silicone rubber. The results showed that there existed the extreme conductivity and shielding effectiveness (SE) across the tested frequency range from 2.6 GHz to 3.95 GHz of silicone rubber composites filled with carbon fibers. When the content of the carbon fibbers was 50 parts per hundred of rubber (phr), the SE values of composites were typically above 63 dB and close to the extremum. The compact packing structure of carbon fibers does not play an important role in improved the conductivity of composite. The SE of the composite depends on the conductivity of composite.

As a simple and useful approach, vapor-phase photografting acrylic acid was used to modify the surface of PET films. Catalyst of silver nanoparticles was distributed on the photografting PET films equably after reducing by ascorbic acid. Topography of the pristine, grafting and metallized PET films was characterized by scanning electron microscope (SEM). XRD and FTIR-ATR were also used to analyze the electroless plating copper layer and the grafting PET film respectively.

In this paper，electroless Ni-P plating on copper substrate at 50 °C in ultrasonic field was carried out. The frequency of ultrasonic waves was 40 kHz. The effect of ultrasonic on the composition, plating rate and morphology of Ni-P deposite was investigated at the ultrasonic power of 40, 70 and 100 W. The experimental results showed Ni-P deposit could not be obtained without ultrasonic field at 50 °C. The content of nickel and the thickness of Ni-P deposit increased with the ultrasonic waves power increase. Ultrasonic irradiation power remarkably refines the nodule size of Ni-P particles. The collapse of cavities in solution seems to suppress the Z-direction growth of the nodule.

Anodic coatings were obtained by micro-arc oxidation on AZ91HP magnesium alloys in a solution containing 10 g/L NaOH and 8 g/L phytic acid. The effects of electric parameters including frequency, final voltage, duty cycle and current density on the corrosion resistance of anodic coatings formed on the magnesium alloys were investigated by using an orthogonal experiment of four factors with three levels. The results show that the final voltage plays a main role on the coating properties. The orders of affecting corrosion resistance and coating thickness are separately ranked from high to low as, final voltage>duty cycle>current density>frequency and final voltage>current density>frequency>duty cycle. The final voltage influences the corrosion resistance of the anodized samples mainly by changing the surface morphology and coating thickness.