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Heavy metal stored in the sediment of shaollow lake will be released into water bodies when sediment resuspension occurs, causing secondary pollution. This study was conducted to probe the distribution and transportation of Zn, Cu, Cr, Pb among overlying water, pore water, SS and vegetation in 30d using three annular flumes. Iris pseudacorus L was planted in two flumes at the wind speed of 8.7m/s,6.5m/s respectively. Another flume was designed as a control at the wind of 8.7m/s under the condition of no plants. The results reavaled Iris pseudacorus L had strong enrichment on heavy metals. Total heavy metal (Zn、Cu、Cr、Pb) concentrations in sediment slightly decreased. The diffusion of metals in pore water showed greatly downward and the concentration in SS decreased with fluctuation with the increasing contents of dissolved metals in overlying water. Correspondingly, plants also appeared a gradual upward trend. The results of the study may work as a foundation for the phytoremediation of heavy metal pollution in shallow lake.

The effects of different packaging materials (including CPP, LDPE, HDPE, PP6, PP12, OPP and PO) on the changing of O2 and CO2 content in Red Fragrant Pear MAP during storage at different initial air conditions were studied in this paper. Gas composition was affected by respiration rate of pear and the permeability of packaging material remarkably. The results showed that OPP, LDPE and CPP were better for maintaining the desired atmosphere composition of O2, CO2, N2 during preservation of red fragrant pear. In addition, 100% N2 as initial gas was more suitable to preserve red fragrant pear than that with air or vacuum significantly.

To investigate the biodegradability of PBS, films made of PBS were subjected to enzymatic degradation. The declining thermal stability and XRD diagrams showed that the crystallinity of PBS was reduced after degradation. SEM results confirmed that the mode of enzymatic degradation was surface corrosion. In addition, the weight loss of the material did not experience the so-called acclimation period, but showed a typical linear growth process.

The lignin removal of pulping process is left in black liquor, and with relation to the paper pulp lignin. The higher the black liquor lignin content is, the bigger the lignin of paper pulp is removed. This paper analyzes the delignification mechanism of wheat straw atmospheric pressure pulping with microwave radiation. The relations of black liquor lignin content and alkali concentration to pulping time are described in detail. The results show that delignification process is divided into two stages: quick stage and residual stage. The lignin removal rate in the first stage is much higher than the second stage, that is, lignin has been removed more sufficiently after quick stage. In first stage, reaction order of delignification is 1.0, and 0.7 with respect to OH-, the activation energy is 38.62 kJ • mol-1. The latter delignification also belongs to the first-order reaction and 4.4 with respect to OH-, the activation energy is 75.56 kJ • mol-1. Apparently, residual stage needs to consume large amounts of energy to removal lignin.

The crystallization properties of P(3HB-co-4HB) modified with nucleating agent BN was studied. DSC is used to analyze the melting crystallization behavior and POM is used to characterize crystal structure and morphology. The results show the incorporation of BN decreased the spherulite size, increased the crystallization rate and improved the crystallization properties of P(3HB-co-4HB).

Brewer’s spent grain (BSG) protein extracted from BSG was hydrolyzed using Alcalase to produce BSG protein hydrolysate. BSG protein hydrolysate was fractionated by ultrafiltration to obtain brown color BSG peptides. Antioxidant activity of BSG peptides was analyzeded and compared with reduced glutathione (GSH). BSG peptides exhibited 50% of scavenging activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, and superoxide radical with concentrations less than 0.8 mg/mL, 0.6 mg/mL and 0.6 mg/mL, respectively. The reducing power of BSG peptides was 0.70 at the concentration of 2.00 mg/mL. 86.30% of the total amount of the BSG peptides purified by gel permeation chromatography was below 2000 Da. Because of its antioxidant activity, stability, nutritive value and low cost, BSG peptides exerts a possibility to use in food or cosmetic products.