Advanced Materials Research Vols. 396-398

Abstract: A novel flame retardant of methylmethoxyphosphonate aluminium (MMPA) was synthesized via the reaction of anhydrous aluminum chloride and dimethyl methylphosphonate (DMMP). The effects of introducing order of reactants, reaction time and washing agents were investigated to get pure target compound with higher yields.Application experiments indicates that MMPA is an effective flame retardant for PBT, especially when it is used in intumescent flame retardant（IFR） systems. When the composition of IFR is 20% wt., the limited oxygen index(LOI) value of the IFR-PBT is 30 and can pass the UL94 V-0 test.

Abstract: Abstract. Low- and full-fat cheeses were fermented by Lactobacillus acidophilus and adjunct cultures Streptococcus thermophilus. After ripening for 90d at 4°C, the protein had been proteolysed in different degrees. The results showed that protein content of low- and full-fat cheese were all decreased after 90 d ripened, which the low-fat cheese was 40.45% and full-fat cheese was 28.68%. The soluble nitrogen contents at pH 4.6 (pH 4.6 SN) were 4.97% and 3.88%, and 12% (w/v) trichloracetic acid soluble nitrogen (12% TCA-SN) were 5.17% and 3.74% in low- and full-fat cheese respectively. After ripening for 90d at 4°C it was found that a part of protein in cheese were degraded into amino acids determined by automatic amino acid analyzer, total amino acids contents in low- and full-fat cheese were 29.17 mg•100g-1 and 16.02 mg•100g-1, respectively.

Abstract: The effect of blanching on β-carotene degradation of cabbages during drying was evaluated, and the β-carotene degradation was further simulated by a kinetic model. The β-carotene content of the cabbages decreased when the drying time and temperature increased. The blanched cabbages hold the β-carotene content and color of the cabbage as the unblanched one comparing with the un-blanched cabbages. The kinetic analysis showed the activation energy of the blanched and un-blanched cabbages was 14475.38 and 15429.36 J/mol, which was the main reason resulted in the mentioned results. Therefore, blanching helped to hold the β-carotene content and color of cabbages.

Abstract: Aroma was extracted from fresh Mango juice by solvent extraction, simultaneous distilled extraction and solid phase micro-extraction. The chemical components of aroma were analyzed by GC-MS and check up, compared carefully. The results show that the ingredients and contents of the aroma obtained by these different ways are different. The main chemical components that were extracted by solvent extraction are Terpinolen(73.65%), Ocimen(6.46%), beta-Pinene (3.2%), Limonene(2.4%); that by simultaneous distilled extraction are Terpinolen(81.77%),Ocimene (5.79%), Limonene(2.68%), 3-Caren(2.21%); that by solid phase micro-extraction are Terpinolen(82.09%), 3-Caren(5.21%), Limonene(4.35%), Ocimene (3.47%).

Abstract: To study the effect of microwave output power on the drying kinetics of tilapia fillets, the drying experiments were carried out at 150W, 250W, 500W, 700W and 900W, respectively. And ten mathematical models were involved to fit experimental data. It was found that Midilli et al model gave a best fitness for this conditions applied. Besides, effective moisture diffusivity increased progressively from 1.6248×10^-9 (m²/s) to 10.0735×10^-9 (m²/s) as the power increased from 150W to 900W. In addition, to obtain more homogeneous samples, temperature distribution of tilapia fillets was analyzed when they were put in different layout forms.

Abstract: CuO/γ-Al2O3 catalysts were prepared by supercritical CO2 (SC-CO2) impregnation method. The preparation was carried out in SC-CO2 with Cu(NO3)2 as precursor, methanol as assistant solvent, and γ-Al2O3 as support. The effects of impregnation parameters such as temperature and pressure of SC-CO2, impregnation time, ratio of precursor to support, and amount of assistant solvent on catalyst preparation were investigated. The as-prepared catalysts were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis and compared to that prepared by the conventional impregnation method. The SC-CO2 impregnation method provided higher adsorption rate, larger adsorption quantity, more homogeneous dispersion of precursor, and stronger interaction between precursor and support. The catalytic degradation of methylene blue (MB) was used as probe reaction to estimate the catalytic activity of two catalysts prepared by two methods. The catalyst prepared by SC-CO2 impregnation method exhibits significantly improved catalytic activity. These results show that the inorganic metallic reagents as precursor with assistant solvent can be used as an alternative for the organometallic precursors in SC-CO2 impregnation method.

Abstract: A direct esterification synthesis of glucose undecylenic acid sugar monoester is described, using the immobilized lipase enzyme NOVO-435 in 2-methyl-2-butonal and in ethyl methyl ketone (EMK). conditions were optimized in order to produce the monoester more rapidly and in higher yield. After the reaction product was purified, mass spectroscopy revealed that it had a molecular weight of 346.2 AMU. Further characterization by ¹H and ¹³C NMR spectroscopy was carried out, including two-dimensional (2D) ¹H-¹H COSY and heteronuclear ¹H-¹³C HSQC experiments. These data enabled identification of the monoester product to be 6-O-(10-undercylenoyl)α-D-glucose (74%), and 6-O-(10-undercylenoyl)β-D-glucose (26%) in methanol solution.

Abstract: Purple sweet potato pigment is a natural food pigment, the stability is important to its quality assurance. The effects of metal ions on the stability of purple sweet potato pigment were investigated. The results showed that Mg2+and Fe3+ were conductive to pigments stability in the initial storage, and with the concentration increased, the pigment was more stable. But K+, Ca2+, Na+, Cu2+, Mg2+ and Fe3+ had brought the color density, the color intensity and the preservation rate of purple sweet potato pigment down in the long-term storage.

Abstract: The enhancive effects of lactic acid on the antibacterial activities of haw pectic oligosaccharides (HPOS) against the Gram positive bacteria Staphylococcus aureus, Bacillus subtilis and Streptococcus faecalis, were investigated. Both HPOS and lactic acid showed dose and pH dependent antibacterial activity against S. aureus and B. subtilis. S. faecalis was sensitive to the HPOS but was resistant to the lactic acid. The antibacterial activity of HPOS against these three bacteria could be enhanced by co-treatment with lactic acid. The results revealed that HPOS may be useful as a food preservative, and lactic acid was able to enhance the antibacterial activity of HPOS, allowing for a further improvement in its efficiency. This additive effect obtained with lactic acid would likely result in a reduction in the dosage necessary for food preservation.

Abstract: Organosilicon compound are widely used in pulping and papermaking industry. The quality and capability of paper sheet are distinctly affected by the use of organosilicon. The application of organosilicon used as softening agent, defoamer agent, strengthening agent were introduced one by one in this paper.