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Table of Content

    28 October 2015, Volume 35 Issue 5 Previous Issue    Next Issue
    Frontier Orbital Energy Levels of Dehydroabietic Acid-based Diarylamines
    GAO Hong, SHEN Ming-gui, WANG Xian-kai, SONG Zhan-qian, SHANG Shi-bin
    2015, 35 (5):  1-4.  doi: 10.3969/j.issn.0253-2417.2015.05.001
    Abstract ( 761 )   PDF (717KB) ( 634 )   Save
    Band edges and onset oxide potentials of compounds a-g were studied through UV-Vis spectra and cyclic voltammetry curve. Their highest occupied and lowest unoccupied molecular orbital (HOMO/LUMO) levels as well as energy gaps were calculated by empirical formula, and the relationship between energy gaps and fluorescent properties were discussed. The results showed that compounds e and f with big conjugated naphthalene and biphenyl and compounds b and g with methoxy and methyl substituent groups on aryl rings had smaller energy gaps compared with the others. These compounds would be easily excited, and then they would have better fluorescent properties. In addition, variation tendency of energy gaps by experimental was substantial agreement with that by optimized data.
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    Changes of Cellulose Polymerization and Crystallinity Degrees during Enzymatic Hydrolysis
    DU Min, LI Xin-ping, CHEN Li-hong, WANG Zhi-jie, LI Hong-kui
    2015, 35 (5):  5-9.  doi: 10.3969/j.issn.0253-2417.2015.05.002
    Abstract ( 916 )   PDF (532KB) ( 766 )   Save
    Complex cellulase named Celluclast 1.5L and endo-cellulase named Novozym 476 were applied to hydrolyze the bleached softwood fiber. In the present study, the influences of these two kinds of cellulases on the degree of polymerization (DP) and crystallinity of cellulose were investigated. The results indicated that the DP of cellulose decreased gradually with the increase of the enzyme dosage after hydrolyzed by both cellulases. While the dosage of Celluclast 1.5 L was 3.0 FPU/g, the yield of cellulose was 94.34%. The DP of cellulose decreased to 862 and decreased by 25.95% compared with the control sample (1 164). While the Novozym 476 was in the dosage of 50.0 U/g, the cellulose yield was 94.93%. The DP of cellulose decreased to 711 and decreased by 38.92% compared with the control sample. This showed that in the circumstances of same yield, the cellulose hydrolyzed by Novozym 476 had a lower DP compared with the cellulose hydrolyzed by Celluclast 1.5 L. It meant that endoglucanase was the main factor which led to the decline of DP. With the increase of enzyme dosage of Celluclast 1.5 L, cellulose crystallinity took the changes of M-type, in other words, increased first and then reduced, and finally increased and reduced again. With the increase of enzyme dosage of Novozym 476, the cellulose crystallinity decreased first, and then increased and decreased again.
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    HPLC and MALDI-TOF-MS Analysis of Hydrolysates of Xylan
    LI Hai-long, LI Cheng-guo, QIN Guang-hui, LIU Jian, GAN Li-hui, XIE Ru-sheng, LONG Min-nan
    2015, 35 (5):  10-14.  doi: 10.3969/j.issn.0253-2417.2015.05.003
    Abstract ( 952 )   PDF (844KB) ( 795 )   Save
    The hydrolysis end products of beechwood xylan, which were released by sulfuric acid or enzymes and then labeled at their reducing ends with 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization, were analyzed by HPLC assisted with MALDI-TOF-MS. Some of the hydrolysates, which were lack of related commercial available standard substances, were determined. It was found that the xylose and 4-O-methyl-glucuronic acid-xylose (B2) were the main products with minor amounts of 4-O-methylglucuronic acid (B1) in the hydrolysates of beechwood xylan by sulfuric acid. Recombinant endo-β-1,4-xylanase AnXyn10C released xylose, xylobiose, and 4-O-methyl-glucuronic acid-xylotriose (B3) as the main hydrolysates from beechwood xylan, whereas recombinant endo-β-1,4-xylanase HoXyn11A released xylose, xylobiose, xylotriose, 4-O-methyl-glucuronic acid-xylotetrose (B4) and -xylopentaose (B5), and aldohexaouronic acid. These results revealed that HPLC assisted with MALDI-TOF-MS based on PMP derivatization was a very useful and robust method for the determination of products in hydrolysis of xylan.
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    Properties of Wood Plastic Composite Reinforced by Cellulose Nanofibers
    LI Jing-jing, SONG Zhan-qian, LI Da-gang, SHANG Shi-bin, GUO Yong
    2015, 35 (5):  15-21.  doi: 10.3969/j.issn.0253-2417.2015.05.004
    Abstract ( 883 )   PDF (1423KB) ( 805 )   Save
    The poplar cellulose nanofibers (CNF) were extracted from poplar flour and used to reinforce the wood flour/high density polyethylene(HDPE) composite by physical pretreatment method and polyethylene oxide (PEO) dispersion agent method. Then the wood flour/HDPE/CNF composites were prepared by extruding molding. The effect of dispersion and reinforcement of CNF in the wood flour/HDPE/CNF composites was investigated by a comparioson of two pretreatment methods using compounding method as control. The results indicated that CNF with a diameter of several hundred nanometers could be achieved successfully after the effectively removing of the lignin and hemicellulose of poplar by chemical and mechanical treatments. SEM images showed that an ideal dispersion of CNF in the HDPE matrix of the the wood flour/HDPE/CNF composites could be obtained by using these two pretreatment methods. CNF were entangled with wood flour and HDPE matrix forming a three-dimensional network structure, and the fracture mode of the composites became the ductile fracture. The bending strength and elastic modulus of the wood flour/HDPE/CNF composites prepared with the two pretreatment methods were improved evidently. The bending strengths of the composites by the physical pretreatment method and the PEO dispersion agent method were 43.3 and 38.7Mpa,which was increased by 36.2% and 21.7% respectively compared to the control 31.8 MPa. The elastic modulus of the composites were 3 342 and 3 008 MPa with these two pretreatment methods, increasing by 48.9% and 34.1% than the control 2 243 MPa. The bending strength and elastic modulus of the composites with the physical pretreatment method were higher than those of the composites with the PEO dispersion agent method. This indicated that the physical pretreatment method was an environmental friendly and effective method.
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    Solubility of Poplar Powder in 1-Ethyl-3-methyl Imidazole Acetate
    LI Feng-feng, CHEN Jia-chuan, ZHANG Zhi-li, YANG Gui-hua, PANG Zhi-qiang
    2015, 35 (5):  22-28.  doi: 10.3969/j.issn.0253-2417.2015.05.005
    Abstract ( 741 )   PDF (1628KB) ( 618 )   Save
    The solubility of poplar powder in EmimAC was studied. By single factor and orthogonal experiment, the optimum dissolution conditions were obtained as follows: dissolution temperature 160℃,dissolution time 16 h,moisture content of poplar powder 7.5%, time by ultrasonic waves 10 min. Under the optimum dissolution conditions, the dissolution rate was 48.30%. Furthermore, the total insoluble content of lignin increased at first and then decreased.It reached the maximum value of 29.29% when the dissolution time was 6 h. The structures of poplar powder before and after dissolving were analyzed by SEM,XRD and FT-IR. It was found that structure damage of poplar powder occured when the dissolution time was 16 h, and the crystallinity reduced from 45.43% to 29.03%. However, there are no corresponding derivatives generated from dissolution process. This paper showed that EmimAC was a strong and effective direct solvent.
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    Isolation and Characterization of Hemicellulose from Moso Bamboo Green and Bamboo Yellow
    HUANG Cao-xing, HE Juan, MIN Dou-yong, LI Xin, YONG Qiang
    2015, 35 (5):  29-36.  doi: 10.3969/j.issn.0253-2417.2015.05.006
    Abstract ( 835 )   PDF (1869KB) ( 798 )   Save
    Bamboo green and bamboo yellow separated from Moso bamboo residues were delignified by NaClO2 after grinded, sifted and dewaxed by toluene-ethanol to achieve holocellulose. The resulted holocellulose was constantly extracted with 1%, 5% and 10% KOH to obtain hemicellulose. The yields of hemicellulose acquired from bamboo green and bamboo yellow were calculated as 81.74% and 85.36%, respectively. Then, the chemical compositions and structures of these hemicelluloses were characterized by HPAEC, GPC, FT-IR, 1H NMR and 2D HSQC techniques. The results indicated that the proportions of xylose in the bamboo green and bamboo yellow hemicellulose preparations were 61.02%-73.76% and 65.22%-80.00%, respectively. The weight average molecular weight of hemicellulose preparations of bamboo yellow were 44 870-48 560 g/mol, which were higher than that of bamboo green hemicellulose preparations (43 970-46 245 g/mol). It was demonstrated that the back chain of hemicelluloses were composed of β-D-xylan. Meanwhile, α-L-arabinofuranose and 4-O-methyl-α-D-glucuronic acid were linked to back chain of hemicellulose at C-3 and C-2 of xylan, respectively, and part of lignins were linked to hemicelluloses by phenyl glucoside bond.
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    Preparation and Characterization of Magnetic Polystyrene/Fe3O4 Microspheres with Rosin Moiety
    YU Cai-li, REN Peng, WANG Xiao-lei, CHEN Chuan-wei, ZHANG Fa-ai
    2015, 35 (5):  37-44.  doi: 10.3969/j.issn.0253-2417.2015.05.007
    Abstract ( 744 )   PDF (1054KB) ( 625 )   Save
    Rosin was reacted with 2-hydroxyethyl methacrylate and an ester (denoted as RH) was formed. Then polymerization was carried out in the presence of oleic acid-modified Fe3O4 magnetic fluid, with RH and styrene (St) as monomers, divinylbenzene (DVB) as cross-linking monomer, gelatin as dispersant, 2,2-azobisiso-butyronitrile (AIBN) as initiator. The magnetic polymer microspheres with rosin moiety were prepared by suspension polymerization and the effect of the magnetic fluid content on the magnetic polymer microspheres was investigated. The structures and properties of the magnetic polymer microspheres were characterized by Fourier transform-infrared spectroscopy, thermogravimetry, X-ray powder diffraction, optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectrometer. Hysteresis loops of the microspheres were tested by magnetic measuring system. The results indicated that at a monomer ratio of m(RH):m(St):m(DVB)=1:1.5:0.4, and the amounts of AIBN and gelatin about 1% and 6% of the total monomers, respectively, the products were spherical with high superparamagnetism. When the amount of oleic acid-modified Fe3O4 increased, the particle sizes of microspheres were gradually increased, the particle size distribution was broadened, and the saturation magnetic intensity increased.
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    Adsorption Characteristics of Carboxymethylated Lignin on Avennectins Particles Surfaces
    HAO Han, CHEN Bao-ying, CHEN Wei-tao, GUO Xin-yu, LIU Wen-jun, WU Xue-min
    2015, 35 (5):  45-52.  doi: 10.3969/j.issn.0253-2417.2015.05.008
    Abstract ( 779 )   PDF (1022KB) ( 796 )   Save
    The analysis by FT-IR, GPC and functional groups content tests indicated that carboxymethylated lignin (CML) had higher molecular weight, lower polydispersity, less phenolic hydroxyl and more carboxyl content than those of alkali lignin (AL). In order to investigate the feasibility of using CML to disperse avennectins particles in aqueous suspension, the adsorption isotherm, kinetics and thermodynamics of CML on avennectins particles surfaces were studied by batch equilibrium experiments. The results showed that the adsorption of CML was fitted to Langmuir isotherm equation, and the saturated adsorption amounts and Langmuir constants decreased with temperature increasing. The maximum saturated adsorption amount was 9.569 mg/g, and 0<RL<1 indicated that the adsorption process was feasibility. The adsorption process followed the pseudo-second-order kinetic model with the entire adsorption, and the adsorption rate constants increased with temperature increasing. The equilibrium adsorption time was approximately 60 min. The thermodynamic parameters were obtained as ΔGad<0, ΔHad<0 and ΔSad>0. This indicated that the adsorption was a spontaneous, exothermic and entropy process. Theoretically, high temperature was not beneficial to the adsorption process. The values of ΔHad=-5.18 kJ/mol implied that Van der Waals forces were responsible for the binding of CML with avennectins. The values of Ea=14.23 kJ/mol indicated that the adsorption process was physical adsorption. The SEM showed that abamectin particle surface was smooth without hole structure. Abamectin particles adsorbed by CML could prevent particle from aggregation effectively, and increase physical stability of abamectin SC. The adsorption characteristics study demonstrated that CML was able to form stable adsorption on avermectin particles surfaces, and eligible to be used as a suspending agent in avermectin suspension.
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    Preparation of Renewable Fuel from Saponificated China Tallow Oil by Fast Pyrolysis Reaction Assisted with Microwave
    WANG Yun-pu, CHENG Fang-yuan, LIU Yu-huan, RUAN Rong-sheng, LIU Ying-yu, MA Wen, YANG Qian, HUANG Yi-ning
    2015, 35 (5):  53-57.  doi: 10.3969/j.issn.0253-2417.2015.05.009
    Abstract ( 715 )   PDF (1039KB) ( 587 )   Save
    Preparation of renewable fuel was studied with saponificated China tallow seed oil and stillingia oil as raw materials using microwave pyrolysis. The effects of reaction power and temperature on the yield of pyrolysis products were investigated. The optimum conditions were obtained as pyrolysis power 700 W, pyrolysis temperature 450 ℃. The corresponding liquid yields were 75.26% and 77.01% for microwave pyrolysis oil from saponificated China tallow seed oil and stillingia oil, respectively. The GC-MS analysis indicated that the main components of the product were C8-C18 alkanes, alkenes, ring-containing alkanes and aromatic hydrocarbon. Pyrolysis oil properties were also determined. The results indicated that the pyrolysis oil from saponificated China tallow seed oil had higher heat value, lower density and viscosity with the comparation of pyrolysis oil from saponificated China tallow stillingia oil, which was similar to 0# diesel. Freezing point and cold filter plugging point of the pyrolytic products have good low temperature fluidity, which are better than those of the biodiesel.
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    Study of Squalene Microcapsule by Spray Drying Technology
    YOU Feng, HUANG Li-xin, ZHANG Cai-hong, XIE Pu-jun, ZHANG Yao-lei
    2015, 35 (5):  58-64.  doi: 10.3969/j.issn.0253-2417.2015.05.010
    Abstract ( 883 )   PDF (1706KB) ( 672 )   Save
    The microcapsule of squalene was carried out by ultrasonic-assisted emulsion, homogenization and spray drying using mixture of gelatin, arabic gum, maltodetrin as wall material, sucrose ester and tween-80 as emulsifier. The conditions of ultrasonic-assisted emulsion, ratio of wall materials, emulsifier amount and spray drying parameters were studied. The microcapsules produced respectively by spray drying and freezing drying were compared in this paper. The optimum process was showed as squalene 3.0 g and tween-80 0.6 g were emulsified under 240 W for 4 min, and then mixed with water as solid content 3.88% with gelatin 2.0 g,arabic gum 2.0 g,maltodetrin 10.0 g,sucrose ester 0.5 g; the inlet and outlet temperatures for spray drying were 180 ℃ and 105 ℃; and the spray air speed was 1.5 m3/h and feeding rate was 6 mL/min. Under these conditions, the encapsulation efficiency was 92.3% and the microcapsule was nearly spherical, the mean size was about 12.0 μm. Microencapsulated products by spray drying had higher encapsulation efficiency, smaller particle size and higher reliability compared with the products by freeze drying.
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    Synthesis and Characterization of A Novel Lignin Model Compound Named Guaiacylglycerol-β-guaiacyl Ether
    YANG Xiao-hui, XIAO Guo-min, JIANG Jian-chun, ZHOU Yong-hong
    2015, 35 (5):  65-70.  doi: 10.3969/j.issn.0253-2417.2015.05.011
    Abstract ( 695 )   PDF (1308KB) ( 589 )   Save
    A novel lignin model compound named guaiacylglycerol-β-guaiacyl ether (SG) was synthesized from acetosyringone via bromination, substitution, hydroxyl methylation and reduction reaction. Its structure was characterized by FT-IR, 1H NMR, 13C NMR, HRMS and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis showed that the compound was of triclinic system, space group P-1 with a=0.724 20(14), b=1.077 0(2), c=1.2054(2) nm, β=90.43(3)°, V=0.858 0(3) nm3, Z=2, Mr=350.36, F(000)=372, μ(MoKα)=0.104 mm-1, DC=1.356 g/cm3, λ=0.071 073 nm, the final R=0.060 2 and wR=0.162 1. In addition, the dimer was formed through intermolecular hydrogen bonds in crystal packing of the title compound.
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    Preparation and Performance of Slow Release Formulation Based on Lignin Derived Trimethyl Quaternary Ammonium Salt/Bentonite
    TIAN Jin-ling, REN Shi-xue, FANG Gui-zhen
    2015, 35 (5):  71-78.  doi: 10.3969/j.issn.0253-2417.2015.05.012
    Abstract ( 626 )   PDF (1223KB) ( 668 )   Save
    In order to enhance the added value of lignin products, the slow release formulation based on lignin derived trimethyl quaternary ammonium salt/bentonite(L-Bt) was synthesized with using sodium-based bentonite as a raw material and trimethyl quaternary ammonium lignin (T-QL) as the modification agent. Hymexazol was selected as a simulate pesticide. The adsorption and slow release performance of L-Bt formulation for hymexazol were investigated. The structure and basal spacing of modified bentonite were analyzed by FT-IR and XRD. The results showed that quaternary ammonium ion was successfully loaded on bentonite. The modification caused the expansion of the interlayer domain of bentonite, and led to the increase of the basal spacing. The optimum adsorption conditions for hymexazol were L-0.8Bt (the T-QL dosage was 0.8 times of cation exchange capacity (CEC) of bentonite), the dosage of L-0.8Bt 0.06 g, adsorption time 10 h, mass concentration of hymexazol 500 mg/L and pH value of 4. Additionally, the effect of potion proportion and temperature on the cumulative release rate of L-0.8Bt with the maximum adsorption capacity 281 mg/g was studied by water soluble method. The result showed that Accumulative drug release rate increased gradually with the increase of loading drug ratio and temperature.
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    Mechanism of Polyethylene Glycol Treatment for Improvement of Enzymatic Hydrolysis of Acid Steam-exploded Corn Straw
    ZHANG Min, ZHOU Jie, ZHANG Ding-wei, YU Heng, LI Yao, JIANG Ting, OUYANG Jia
    2015, 35 (5):  79-84.  doi: 10.3969/j.issn.0253-2417.2015.05.013
    Abstract ( 821 )   PDF (1222KB) ( 640 )   Save
    In order to investigate the mechanism of PEG4000 addition on enhancement of the enzymatic hydrolysis using the acid steam-exploded corn straw(ASCS) as the raw material, its physochemical properties such as composition, BET and elemental analysis of the substrate, were studied. Based on these results, the effect of PEG on hydrolysis process was studied, and the mechanism was also explored. Moreover, structural changes of substrates before and after hydrolysis were analyzed by FT-IR and SEM. Acid steam-exploded corn straw had a high lignin content with a large BET surface area. With the dose of cellulase 15 FPIU/g (calculated by cellulose) and glucosidase 30 U/g, the glucose conversion of 50 g/L ASCS could reach 76.4% by hydrolysis time of 24h. PEG addition could effectively improve the enzymatic hydrolysis of the acid steam-exploded corn straw, which increased the conversion up to 82.6%. The mechanism analysis showed that PEG could effectively reduce the unproductive adsorption of enzyme on the ASCS. The addition of PEG could increase the soluble protein, filter paper activity (FPA), and β-glucosidase activity (β-GA) in the supernatant by 15.0%, 112.5% and 24.8%, respectively. The FT-IR analysis showed that the crystal form of ASCS was cellulose Ⅱcrystal structure. The SEM images showed the addition of PEG caused the collapsing of cellulose structure and the residue appeared as irregular bulk.
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    Preparation and characterization of lignin nanoparticles with controllable size by nanoprecipitation method
    XIONG Kai, JIN Can, LIU Gui-feng, WU Guo-ming, CHEN Jian, KONG Zhen-wu
    2015, 35 (5):  85-92.  doi: 10.3969/j.issn.0253-2417.2015.05.014
    Abstract ( 1346 )   PDF (960KB) ( 1022 )   Save
    Lignin nanoparticles (NPs) with controlled particle size were prepared by a nanoprecipitation method from acetic acid lignin, where the lignin was not modified particularly by any functional group. The preparation conditions, which could affect the size and feature of lignin NPs, were investigated in detail. The most suitable conditions were stirring rate above 300 r/min, dropping rate 5-40 mL/h, volume ratio of tetrahydrofuran (THF) to H2O 5:100-10:100 and concentration of lignin solution 10-20 g/L. The chemical structure, morphology and physicochemical properties of lignin NPs were characterized by electronic microscope, infrared spectroscopy, X-ray diffraction, elemental analysis, X-ray photoelectron spectroscopy and contact angle measurements, respectively. The results indicated that the average diameter of lignin NPs was 150 nm approximately, and the lignin NPs neither chemically changed on their structures nor formed crystalline particle. The lignin NPs with a hydrophilic core and a hydrophobic surface would enhance their stability.
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    Preparation of Xylobiose by Xylanase Hydrolysis in Aqueous Two-phase System and Its Purification
    LI Xin, GU Xi-mei, SHENG Ao-nan, ZHANG Li, CHEN Xiao-pei, YONG Qiang
    2015, 35 (5):  93-97.  doi: 10.3969/j.issn.0253-2417.2015.05.015
    Abstract ( 773 )   PDF (792KB) ( 573 )   Save
    Xylobiose was prepared by xylanase hydrolysis of birchwood xylan in the PEG6000/sodium citrate aqueous two-phase system (ATPS). The optimized conditions for enzymatic hydrolysis in ATPS were birchwood xylan 10 g/L, xylanase 20 IU/g (calculated by the mass of xylan), 50 ℃ and pH 5.6. The enzymatic hydrolysis yield of xylobiose was 13.8% for 8h. The recoveries of xylanase and xylobiose were 66.4% and 87.2%, respectively. Then, purification of xylobiose was carried out on Sephadex LH-20 with using degassed high purified water as eluent. The optimized conditions for purification of xylobiose were column temperature 35 ℃, 0.1 mL/min and sample volume 0.3 mL. After purification, the purity of xylobiose was improved to 98.5% under the optimized conditions.
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    Synthesis and Antibacterial Activity of Rosinyl Choline Quaternary Ammonium Surfactants
    ZHENG Jian-qiang, LIU Li, RAO Xiao-ping, SONG Zhan-qian, SHANG Shi-bin
    2015, 35 (5):  98-104.  doi: 10.3969/j.issn.0253-2417.2015.05.016
    Abstract ( 817 )   PDF (761KB) ( 739 )   Save
    Choline was reacted with dehydroabietic acid, N-(dehydroabietyl)maleamic acid, acrylopimaric acid and maleopimaric acid, respectively, to prepare four rosinyl choline quaternary ammonium surfactants(Ⅰ1-Ⅳ1). And tetramethyl ammonium hydroxide was reacted with the four compounds respectively to prepare four rosinyl quaternary ammonium surfactants without hydroxyl groups (Ⅰ2-Ⅳ2). Their structures were characterized by IR, 1H NMR, 13C NMR spectra. Their critical micelle concentration (CMC), surface tension (γCMC), emulsifying ability, foaming ability, HLB value and bactericidal activity were evaluated. The results showed that CMC values of Ⅰ1, Ⅱ1, Ⅲ1, Ⅳ1 were 6.9, 2.0, 3.8 and 8.0 mmol/L, the corresponding γCMC values were 37.9, 35.1, 40.0 and 42.4 mN/m. The CMC values of Ⅰ2, Ⅱ2, Ⅲ2, Ⅳ2 were 9.4, 5.2, 6.2 and 10.0 mmol/L, the corresponding γCMC values were 39.7, 39.0, 43.1 and 45.1 mN/m. By comparison, CMC values and γCMC of quaternary ammonium salt surfactants with hydroxy groups were smaller than those of quaternary ammonium salt surfactants without hydroxyl groups. It could be seen that the existence of the hydroxyl groups could improve the surface activities of surfactants. HLB values of eight rosin-based quaternary ammonium salts were greater than 18. This showed that they had good hydrophilicity. The foaming ability of Ⅱ1 was better than the others, and foaming height was 202 mm, and then it turned to 165 mm after 5 min. Ⅲ1, Ⅲ2, Ⅳ1 and Ⅳ2 exhibited excellent antibacterial activity against Staphyloccocus epidermidis with minimum inhibition concentration of 2 mg/L, and the antibacterial activities were superior to the Bromogeramine and Ampicillin sodium. It showed that the existence of hydroxyl groups did not affect antibacterial activities of rosin-based quaternary ammonium salt.
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    Separation and Purification of Carnosic Acid from Rosemary Leaves
    XIA Tian-juan, BI Liang-wu, ZHAO Zhen-dong, CHENG Xian, XING Ya-li
    2015, 35 (5):  105-110.  doi: 10.3969/j.issn.0253-2417.2015.05.017
    Abstract ( 1142 )   PDF (1022KB) ( 824 )   Save
    Using the composite method of the following three steps to get carnosic acid from rosemary leaves, the purity of carnosic acid was 21.06% by ultrasound-assisted ethanol extraction. The purity of carnosic acid was 79.62% by ultrasonic-assisted n-hexane extraction and pH adjustment. The optimization conditions of ultrasonic-assisted n-hexane extraction were liquid/solid ratio 20:1(mL:g), ultrasonic frequency 28 kHz, ultrasonic time 40 min, ultrasonic power 140 W. Under these conditions, the yield of carnosic acid was 2.0%. The optimization conditions of silica gel column chromatography were particle sizes of silica gel 48-75 μm, the volume ratio of eluent ethyl acetate and petroleum ether 4:7, the flow rate 6 mL/min and 0.3 g solid loaded. The recovery rate of carnosic acid was 54.12%. The purity of carnosic acid was 95.18% by this method.
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    Preparation of Betulinic Acid by Catalytic Oxidation of Betulin Using Alumina-potassium Dichromate as Catalyst
    XIE Yang, LI Peng, YANG Fan, FU Dong, SUI Xin, ZHANG Hong-wei
    2015, 35 (5):  111-115.  doi: 10.3969/j.issn.0253-2417.2015.05.018
    Abstract ( 868 )   PDF (766KB) ( 545 )   Save
    Betulonic acid was synthesized from betulin by catalytic oxidation using alumina-potassium dichromate as catalyst. The product was identified by FT-IR, 1H NMR and HPLC. The synthetic conditions were optimized by single-factor experiment. The results were the molar ratio of oxidizing agent to betulin 3:1, reaction time 1.5 h, room temperature, and molar ratio of catalyst to oxidizing agent 4:1. Under these conditions, the productivity of betulonic acid was 83.02%. Target compand, betulonic acid was obtained with the yield of 67.25%, and the purity of the refined betulinic acid was 98.3%.
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    Chemical Constituents Extracted from Leaves of Prunus cerasifera Ehrh.cv. Atropurpurea Jacg. and Their Antioxidant Activities in vitro
    WEI Qiang, JI Xiao-ying, LONG Xian-shun, LI Qian-rong, YIN Hao
    2015, 35 (5):  116-122.  doi: 10.3969/j.issn.0253-2417.2015.05.019
    Abstract ( 870 )   PDF (670KB) ( 731 )   Save
    Ethanol extracts from the leaves of Prunus cerasifera Ehrh.cv.Atropurpurea Jacg. were separated and purified by column chromatography over silica gel, Sephadex LH-20 and preparative HPLC. Their structures were identified by spectral methods including 1H, 13C NMR. Seventeen compounds were isolated and identified as β-sitosterol (1), stigmasterol (2), daucosterol (3), lupeol (4), ursolic acid (5), arjunolic acid (6), Niga-ichigoside F1 (7), apigenin (8), kaempferol (9), kaempferol-3-O-β-D-glucoside (10), quercetin (11), quercetin-4'-O-β-D- glucoside (12), hyperin (13), luteolin (14), luteolin-4'-O-β-D-glucoside (15), rutin (16), gallic acid (17). All compounds were isolated from the leaf for the first time. Compounds 11, 14 and 17 showed stronger antioxidant activities by DPPH scavenging activity with IC50 inhibition rates of 32.18, 34.65 and 34.12 mmol/L, respectively, compared with the Vc IC50 inhibition rate of 55.22 mmol/L.
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    Effect of Hybrid Hardeners on Curing Properties of Phenol-formaldehyde Resin
    CHEN Yu-zhu, FAN Dong-bin, QIN Te-fu, CHU Fu-xiang
    2015, 35 (5):  123-128.  doi: 10.3969/j.issn.0253-2417.2015.05.020
    Abstract ( 877 )   PDF (956KB) ( 631 )   Save
    The gel time, pot life and curing properties of phenol-formaldehyde resin (PF) resins induced by single curing agents, namely methylolureas (MMU), propylene carbonate(PC), sodium carbonate (Na2CO3), and their hybrid were investigated. The results demonstrated that the gel times of PF resins induced by single curing agent and two kinds of their counterpart hybrid curing agents were shortened by at least 74s. However, the viscosities of PF resins in presence of PC and MMU+PC increased to 18 000 and 9 000 mPa·s from 178 mPa·s in 3h respectively, and the pot lifes were too short to meet the production requirement of 4 hours at least. The curing agents MMU+Na2CO3 had significant effect on lowering the onset and peak temperature of curing reaction. Thus the aim of fast curing of PF resin, and the needs of production were achieved. Therefore, the curing agent of MMU+Na2CO3 was suitable for fast curing at lower temperature in plywood production.
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    Preparation of Activated Carbon from Alkali Xylose Residue by Phosphoric Acid Activation
    HOU Min, DENG Xian-lun, ZHU Guang-zhen, SUN Kang, GUO Hao, ZHANG Yan-ping, LI Ping, LIANG Fang-min
    2015, 35 (5):  129-134.  doi: 10.3969/j.issn.0253-2417.2015.05.021
    Abstract ( 670 )   PDF (838KB) ( 708 )   Save
    Activated carbon with high adsorption performance was prepared from alkali xylose residue by phosphoric acid activation after pretreatment. The effect of different conditions on the adsorption properties of activated carbon was studied and the pore structure was characterized by N2 adsorption-desorption isotherm. The results showed that the optimum conditions for raw material was pre-activated at 270 ℃ for 60 min and then the activated carbon was prepared at the impregnated ratio 2.0:1(mass ratio), activation temperature 400 ℃, and activation duration 90 min.Under these conditions, activated carbon had the yield of 36.36%, methylene blue value 360 mg/g, iodine value 1 142 mg/g, rate of caramel decolorization 120%, specific surface area 1 850.6 m2/g, total pore volume 1.48 cm3/g, mesopores volume 0.81 cm3/g and average pore diameter 3.2 nm.
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    Qualitative and Quantitative Analysis of Total Triterpenoid Acids in Fruit Extracts of Rosa davurica Pall.
    ZHONG Fang-li, WANG Xiao-lin, YANG Yang
    2015, 35 (5):  135-142.  doi: 10.3969/j.issn.0253-2417.2015.05.022
    Abstract ( 731 )   PDF (1149KB) ( 670 )   Save
    The qualitative and quantitative analysis methods of total triterpenoid acids (TTA) in fruit extracts of Rosa davurica Pall. were established. Both UV and HPLC methods were applied to determine the content of TTA, oleanolic acid and ursolic acid. TLC method was used to accomplish the qualitative identification of ursolic acid in fruit extracts. The concentration of oleanolic acid showed good linear relationship with absorbance at the range of 1.75-15.75 mg/L (r=0.999 1) and the average recovery was 101.60% (RSD 1.23%) in quantitative analysis of TTA with UV method. On the other hand, oleanolic acid and ursolic acid showed good linear relationship at the range of 0.1-1.1 μg (r=0.999 7) and 0.024-0.768 μg (r=0.999 9) respectively and the average recoveries of them were 100.24%(RSD 1.44%) and 100.54%(RSD 0.45%) by HPLC method. The average contents of TTA, oleanolic acid, and ursolic acid of three batches of fruit extracts were 8.62%, 0.273%, and 0.534%, respectively. The experimental results showed that the content determination and TLC qualitative identification methods established could be applied to control of the qualitative and quantitative analysis of fruit extracts of R.davurica.
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    Separation of Methyl Glucosides and Glycerol Aqueous Solution by Nanofiltration
    XIE Ze-an, ZHAO Li-li, LI Lu, LIU Shi-wei, YU Shi-tao
    2015, 35 (5):  143-148.  doi: 10.3969/j.issn.0253-2417.2015.05.023
    Abstract ( 731 )   PDF (985KB) ( 650 )   Save
    Nanofiltration membrane was used to separate simulative biomass liquefaction oil solution consisting of glycerol and methyl glucosides(Meg). The effects of the parameters on NF400-600 spiral-wound nanofiltration membrane separation process were examined during the separation of glycerol and methyl glucosides. The optimum nanofiltration conditions established by single factor test were operating pressure 0.4 MPa, initial concentration 10 g/L, operating temperature 45 ℃. Under the above conditions, the permeate flux was 48.6 L/(m2·h), the retention ratio of methyl glucosides was 95.4%, and the penetration ratio of glycerol was 81.0%. Resistance model was used as the prototype to explore the mathematical models between membrane flux and operating parameters in the process of nanofiltration. The formula of J was J=0.625ΔP/(0.005 28+3.37×10-4ΔP0.017 7C0.901). The results of verification test showed the fitting effect of model agreed well with the average relative error < 6% and maximum relative error < 10%.
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    Research Progress of Aromatics Production from Catalytic Pyrolysis of Biomass
    ZHENG Yun-wu, YANG Xiao-qing, WANG Fei, LIU Can, ZHENG Zhi-feng, GU Ji-you
    2015, 35 (5):  149-158.  doi: 10.3969/j.issn.0253-2417.2015.05.024
    Abstract ( 682 )   PDF (1029KB) ( 855 )   Save
    Due to the important application value and broad market prospect of aromatic hydrocarbons, the research progress on the production of aromatics from catalytic conversion of biomass was reviewed. The effects of feedstock, model compound, zeolite microporous molecular sieve catalyst, mesoporous molecular sieve catalyst and impregnation modification of catalyst as well as reaction condition on reaction selectivity and yield for the formation of aromatics hydrocarbons were summarized in detail. The reaction mechanism were further discussed. This review might provide a new direction for the total components and high value utilization of biomass.
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