Table of Content

30 September 2015, Volume 49 Issue 5 Previous Issue    Next Issue

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Preparation and Antibacterial Activity of Xylon Grafted with Ag Nanoparticles FENG Xiao-yan, CHEN Ying, WANG Chun-peng, CHU Fu-xiang 2015, 49 (5):  1-6.  doi: 10.3969/j.issn.1673-5854.2015.05.001 Abstract ( 683 )   PDF (1179KB) ( 726 )   Save Polyvinylpyrrolidone-Ag nanoparticles (PVP-Ag NPs) were prepared with PVP as stabilizing and dispersing agent and sodium borohydride as reducing agent. Then the PVP-Ag NPs were grafted on xylon via the coupling effect of silane coupling agent to obtain the xylon with antibacterial activity. The structure and morphology as well as the thermal stability of PVP-Ag NPs grafted xylon were characterized by FT-IR, scanning electron microscope and thermal gravity analysis. The results indicated that the optimum reaction conditions of PVP-Ag NPs grafted on the xylon were the dosage of the coupling agent 4%, the coupling time 5 h and the grafting time 10 h. The grafting rate was about 5.8% under these conditions. The inhibitory rates of PVP-Ag NPs grafted xylon against gram-positive Staphylococcus aureus, Bacillus cereus, gram-negative Escherichia coli and Methicillin-resistant Staphylococcus aureus(MRSA) were all more than 95%. Furthermore, the PVP-Ag NPs grafted on wood fiber board possessed excellent antibacterial activity. References | Related Articles | Metrics

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Preparation of Nanocellulose and Its Aerogel from Bagasse Pulp ZHANG Kai-tao, SUN Pei-pei, SHANG Shi-bin, LIU He, WANG Dan, LI Jing-jing 2015, 49 (5):  7-10.  doi: 10.3969/j.issn.1673-5854.2015.05.002 Abstract ( 885 )   PDF (796KB) ( 764 )   Save Nanocellulose (NCC) was successfully prepared from TEMPO-mediated oxidation of bagasse pulp assisted with ultrasonic treatment, then the cellulose aerogel was obtained via freeze-drying. Furthermore, the morphology, structure and properties of NCC and its cellulose aerogel were investigated by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM). The TEM observation showed that obtained NCC had a diameter about 20 nm and a length ranged from 100 nm to 400 nm. XRD analysis inhabited that NCC maintained the structure of cellulose typeⅠ. TG analysis demonstrated that the thermal stabilities of both the oxidized bagasse pulp and NCC became worse when they were compared with the raw material. SEM images revealed that cellulose aerogel exhibited a three-dimensional network structure when the mass fraction of NCC in suspension was 0.1%, while cellulose aerogel displayed a porous "Honeycomb" structure when the mass fraction of NCC was more than 0.1%. References | Related Articles | Metrics

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Preparation of La1-xPrxNiO3 and Its Catalytic Properties on Bagasse High-pressure Liquefaction ZHANG Xiao-hua, TENG Jun-jiang, ZHANG Rong-bin, LI Ning, LU Chao, GAO Xin-hang 2015, 49 (5):  11-16.  doi: 10.3969/j.issn.1673-5854.2015.05.003 Abstract ( 621 )   PDF (1255KB) ( 680 )   Save Perovskite-type oxide catalysts La1-xPrxNiO3 were synthesized by co-precipitation method, and the crystalline structures, shapes and reducing properties were characterized by XRD, SEM and TPR. At the same time, the catalytic performance of La1-xPrxNiO3 on bagasse high-pressure liquefaction reaction and liquefaction product distributions in the process were studied. The results showed that after La3+ partly replaced Pr3+, the peak strength of XRD of La1-xPrxNiO3 enhanced, the micro morphology structure was more loose, the specific surface area by increased, the reduction peak migrated to the direction of high temperature, and the reduction peak area increased. It showed better catalytic activity, promoted the liquefaction of bagasse and reduced the content of residue. When x=0, the residue rate was 30.8%, and the yield of liquefied oil was 41.67%. When x=1, the residue rate was 24.8%, and the yield of liquefied oil was 46.37%. At the same time, the product of large relative molecular mass in liquefied products decreased and the product of small relative molecular mass increased. References | Related Articles | Metrics

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Influence of Alkaline-Fenton Pretreatment on the Enzymatic Hydrolysis Yield of Yunnan Bamboo WANG Yan-yun, YANG Jing 2015, 49 (5):  17-22.  doi: 10.3969/j.issn.1673-5854.2015.05.004 Abstract ( 604 )   PDF (988KB) ( 673 )   Save The optimum reaction conditions of alkaline-Fenton pretreatment of bamboo were obtained through the response surface methodology. The results showed that the optimum conditions of Fenton reaction were alkaline treated bamboo 1 g, 30% H2O23.4 mL, concentration of Fe2+15.8 mmol/L, and reaction time 12 h. The 72 h enzymatic hydrolysis yield was 49.98%. The sample pretreated by 2% NaOH-Fenton had higher cellulose content and lower hemicellulose and lignin content compared with the materials and sample pretreated by 2% NaOH. The 72 h enzymatic hydrolysis yield was 48.24% and increased by 47.79% and 37.44%, respectively. The 72 h enzymatic hydrolysis yield was 76.64% when the dosage of the cellulase and the β-glucosidase were 32 FPIU/g and 16 IU/g, respectively. This was 22.80% higher than that with the single use of the cellulase 32 FPIU/g. References | Related Articles | Metrics

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Synthesis and Performance of Aliphatic Alcohol-based Terephthalate LI Ke, JIANG Jian-chun, NIE Xiao-an, CHEN Jie, CHEN Shui-gen 2015, 49 (5):  23-26.  doi: 10.3969/j.issn.1673-5854.2015.05.005 Abstract ( 643 )   PDF (567KB) ( 690 )   Save The synthesis methods of aliphatic alcohol-based terephthalate were studied using terephthalic acid and saturated aliphatic alcohol (C4, C6, C8, C10 and C14) as raw materials. And the physicochemical properties such as crystallization points, densities, and the flash points et al. were contrasted. The results indicated that the reactions of aliphatic alcohols of C4 and C6 with terephthalic acid at ordinary pressure and low temperature were difficult, and the aliphatic alcohols of C8, C10 and C14 could easily react with terephthalic acid under catalysis. The flash point of butylene terephthalate (C4) was 180 ℃. The melting (crystallization) points of alcohol and ester (C14) were 38 ℃ and 67 ℃, respectively, but it was not convenient for the operation and use. While terephthalic esters of C8 and C10 aliphatic alcohols were between liquid-solid junction, and the flash points were not less than 210 ℃, they were suitable raw material for the synthesis of terephthalic acid esters plasticizer. References | Related Articles | Metrics

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Rapid Prediction of Wood Property of Fast Growing Acacia by Near Infrared Spectroscopy Technique WU Ting, FANG Gui-gan, LIANG Long, ZHANG Xin-min, ZHAO Zhen-yi 2015, 49 (5):  27-33.  doi: 10.3969/j.issn.1673-5854.2015.05.006 Abstract ( 612 )   PDF (1009KB) ( 682 )   Save The chemical compositions and basic densities of 147 fast growing acacia samples were analyzed by using the traditional method, and the near-infrared (NIR) spectra were also collected. Partial least squares (PLS) method and cross-validation were used to confirm the best factor and build the calibration models for holocellulose, lignin, benzene-alcohol extract and basic density after the original spectra were pretreated. The best factors of the four models were 10, 8, 9 and 9. The independent verification of the calibration models showed the coefficients of determinations (R2val) were 0.910 3, 0.950 5, 0.970 6 and 0.969 5, respectively. The root mean square errors of prediction (RMSEP) were 0.45%, 0.32%, 0.21% and 0.007 1 g/cm3, respectively. The relative percentage deviations (RPD) were 3.34, 4.50, 5.82 and 5.73, respectively. And the absolute deviations (AD) were -0.60%-0.68%, -0.50%-0.48%, -0.29%-0.33% and -0.009 7-0.009 1 g/cm3, respectively. The root mean square errors of prediction and the absolute deviations basically met the needs of error and the four calibration models could fulfil the rapid determination in pulping and paper making industry for the good predictive performance. References | Related Articles | Metrics

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Extraction of Effective Ingredients from Scutellaria Bacalensis Georgi WANG Xue, LIU Yan-ge, LU Jia-hui, WANG Chun-yue, JIA Bing-xuan, MENG Qing-fan, ZHANG Yang, WANG Di 2015, 49 (5):  34-38.  doi: 10.3969/j.issn.1673-5854.2015.05.007 Abstract ( 837 )   PDF (851KB) ( 774 )   Save In order to optimize the extraction condition for effective active ingredient from Scutellaria Bacalensis Georgi, a three-factor-three-level experiments design was developed by using Box-Benhken central composite design method based on single-factor experiments with extraction temperature, extraction time, solvent-solid ratio as influence factors. The bacteriostatic ring diameter against Candida albicans was used as the responsive values. The data were fitted by using multi-linear equation and second-order polynomial equation. And the extraction conditions were optimized by response surface method. The optimum conditions were as follows: extraction temperature 61 ℃, extraction time 2 h and solvent-solid ratio 13:1. Under these conditions,the average diameter of bacteriostatic circles verified by three experiments was 12.637 mm closing to the predicted value(12.664 88 mm),when the concentration of extractions was 0.5 g/mL.And the average diameter of bacteriostatic circle of positive contrast was 11.85 mm.The results showed that the aqueous extract of Scutellaria bacalensis Georgi had significant bacteriostatic effects on Candida albicans. References | Related Articles | Metrics

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Review on Experimental and Theoretical Study of Furfural Production from Fast Pyrolysis of Biomass DONG Xiao-chen, YE Xiao-ning, JIANG Xiao-yan, HU Bin, LU Qiang, DONG Chang-qing 2015, 49 (5):  39-46.  doi: 10.3969/j.issn.1673-5854.2015.05.008 Abstract ( 822 )   PDF (1005KB) ( 723 )   Save Furfural was an important product of fast pyrolysis of biomass. It could be selectively produced from controlled fast pyrolysis of biomass. This provided a new way for the production of furfural and value-added utilization of biomass. This paper firstly summarized the experimental studies and density functional theory analysis on the formation mechanism of furfural from pyrolysis of cellulose and hemicellulose. Then this paper concluded the catalytic pyrolysis techniques for the selective production of furfural. Finally, the future research was proposed to reveal the pyrolytic formation mechanism of furfural and optimize the selective furfural production technique. References | Related Articles | Metrics

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Overview of Biomass Torrefaction Technology LIN Qi-chen, ZHANG Wen-biao, SUN Yi, ZHANG Xiao-chun, WANG Sun-guo 2015, 49 (5):  47-52.  doi: 10.3969/j.issn.1673-5854.2015.05.009 Abstract ( 726 )   PDF (798KB) ( 717 )   Save This paper presents a global overview of the torrefaction raw materials, existing torrefaction technologies, characteristics and applications of products, as well as the future opportunities and challenges especially in China. References | Related Articles | Metrics

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Research Progress of Factors Affecting the Formation of Biofuel Pellets HUANG Yan, DU Peng-dong, ZHANG Ming-yuan, TANG Jing-yu, WEI Rui, LIU Ling, WANG Xiao-hong, ZHANG Ji-li 2015, 49 (5):  53-58.  doi: 10.3969/j.issn.1673-5854.2015.05.010 Abstract ( 933 )   PDF (869KB) ( 774 )   Save The literatures about the formation of biofuel pellet research were reviewed. The bonding mechanism and quality parameters of fuel pellet were analyzed, and the influences of material moisture content, storage time, temperature and pressure on pellet quality were summarized. Based on these, a theoretical basis and literature references for reasonable choices of the pelletizing process were provided to improve the physical quality of the biofuel pellets. References | Related Articles | Metrics