Table of Content

28 December 2015, Volume 35 Issue 6 Previous Issue    Next Issue

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Preparation of Porous Cellulosic Absorbing Materials WANG Ai-ting, LIU He, LIU Shi-wei, SHANG Shi-bin, YU Shi-tao 2015, 35 (6):  1-7.  doi: 10.3969/j.issn.0253-2417.2015.06.001 Abstract ( 938 )   PDF (9014KB) ( 599 )   Save Cellulose was dissolved in NaOH/urea/H2O solution system and crosslinked with neopentyl glycol diglycidyl ether(NGDE).Then, the crosslinked products were purified by deionized water and freeze-drying to prepare porous cellulosic absorbing materials.The chemical composition, crystal structure, thermostability and morphological feature of the materials were analyzed by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM), respectively.The effects including the amount of NGDE and the mass fraction of hydrogel on the density and the water absorption ability of porous cellulosic materials were investigated.The results showed that 4 g cellulose was dissolved in 100g NaOH/urea/H2O solution and the amount of NGDE was 18 mL and the mass fraction of the hydrogel was 1.5%, the density of the prepared materials reached 15.7 mg/cm3 and water absorption ration was 37 times.The structure of materials prepared in this condition was characterized. The results showed that the cellulosic absorbing materials exhibited continuous network pore structure and the crystal structure was transformed from the celluloseⅠcrystalline structure to amorphous structure.The porous cellulosic absorbing materials started to degrade above 250℃.This showed high thermal stability. References | Related Articles | Metrics

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Products Distribution of Glucose through Ethanolysis Reaction Catalyzed by Extremely Low Acid under High Temperature CHANG Jun-li, BAI Jing, CHANG Chun, ZHAO Shi-qiang, LI Hong-liang, FANG Shu-qi 2015, 35 (6):  8-14.  doi: 10.3969/j.issn.0253-2417.2015.06.002 Abstract ( 710 )   PDF (1626KB) ( 910 )   Save The distribution of products from glucose catalyzed by extremely low sulfuric acid(≤0.1%)in ethanol and ethanol/co-solvent medium was investigated.The results showed that ethyl levulinate (EL) was the main product in the liquid with a yield of 40.46% under the reaction conditions of glucose concentration 20 g/L, reaction temperature 200 ℃, sulfuric acid concentration 0.1% and reaction time 120 min.The influence of nine kinds of ethanol/solvent system was compared, and the effect of using n-hexane as a co-solvent was further investigated.Moreover, the effect of using n-hexane as a co-solvent was investigated, and similar results of the distribution of products were obtained compared with the results in pure ethanol system.The addition of n-hexane could not increase the yield of EL effectively, but it can improve the concentration of intermediate of 5-ethoxymethylfurfural(EMF).It also can prevent EMF of further hydration to form EL.Ethyl glucoside(EG)was easily obtained from glucose with lower or higher reaction temperature accompanied with shorter reaction time.Increment of the reaction temperature and reaction time has positive effect on generation of EL.The byproducts, such as levulinic acid (LA)and 5-hydroxymethylfurfural(HMF), was accounting for a minority part of the product during the reaction process.According to the distribution of products, a reaction pathway for the extremely low sulfuric acid catalyzed conversion of glucose in ethanol/n-hexane medium was proposed. References | Related Articles | Metrics

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Synthesis and Structural Characterization of Methyl Isopimarate WANG Mi-xia, XU Shi-chao, LU Yan-ju, YUAN Xiao-min, CHEN Yu-xiang, ZHAO Zhen-dong 2015, 35 (6):  15-20.  doi: 10.3969/j.issn.0253-2417.2015.06.003 Abstract ( 796 )   PDF (1922KB) ( 670 )   Save With isopimaric acid as initiating material, oxalyl chloride as the acyl chlorination reagent, isopimaric chloride active intermediate was synthesized.Then under the action of triethylamine, isopimaric chloride was reacted with methanol to obtain methyl isopimarate, and the title compound was characterized by FT-IR, GC/MS, 1H NMR and 13C NMR spectroscopy.By single fraction tests, the influences of reaction time, material ratio, and dosage of triethylamine on these two reactions were explored.The results showed that the optimal synthetic conditions of the reaction were the molar ratio of isopimaric acid and oxalyl chloride 1:1, reaction time 3h in acyl chlorination reactoin, and the molar ratio of triethylamine and isopimaric chloride 1:0.24, reaction time 80min in esterification reaction.Under these conditions, the acyl conversion rate was 99.43%, the target product was white crystal and the total yield was 86.3%. References | Related Articles | Metrics

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Preparation and Performance of Hydroxymethylated Straw Ethanol Residue/Urea-formaldehyde Composite Resin HU Lan-fang, GAO Shi-shuai, ZHAO Lin-wu, WANG Chun-peng, CHU Fu-xiang 2015, 35 (6):  21-26.  doi: 10.3969/j.issn.0253-2417.2015.06.004 Abstract ( 650 )   PDF (2665KB) ( 628 )   Save The hydroxymethylated straw ethanol residue(HER) was prepared from the hydroxymethylation of straw ethanol residue(ER).HER and urea-formaldehyde resin (UF) were then blended to fabricate the HER/UF and the preparation conditions were studied.Lignin in ER and HER were characterized by FT-IR and the dispersibilities of ER and HER in UF were analyzed by SEM.The results showed that the content of hydroxymethyl group in HER was more than that in ER.The increment of hydroxymethyl group in HER decreased with the ER dosage(the mass ratio of ER to formaldehyde) increasing.And HER showed better dispersity compared with ER in the UF resin.The HER prepared under the conditions of 2 000% ER dosage and 0.9% NaOH dosage(the mass ratio of NaOH to HER) had the best performance.Its free formaldehyde was 0.24% and the viscosity was 3 200 mPa·s.When 10%-40% UF resin was replaced by HER, formaldehyde emission of the three-ply boards could meet E0 grade and its bonding strength could meet the requirement of type Ⅱ plywood.And the three-ply board that made by 30% HER/UF had the best performance. References | Related Articles | Metrics

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Modification of Wood Powder by Esterification for the Production of Bio-based Plastic Material HANG Fei, LUO Yan-qing, HONG Jian-guo 2015, 35 (6):  27-32.  doi: 10.3969/j.issn.0253-2417.2015.06.005 Abstract ( 842 )   PDF (1506KB) ( 690 )   Save Mulberry branches wood powder was used as the raw material for preparation of bio-based plastic material.After ball milling, wood powder was first esterified by phthalic anhydride(PA) using 4-dimethylaminopyridine (DMAP)as the catalyst in dimethyl sulfoxide(DMSO)as the dispersion medium.The effects of temperature, time and the weight of reagents on weight percent gain(WPG)and mechanical property of modified production were studied.The results showed that esterified lignocellulosic material could be used as bio-based plastic injection molding product with whole components.Under the optimum conditions, the mass growth rate and melt index of the modified product were 98.8% and 0.903 g/min, respectively, and the modified product was found with good thermoplastic and mechanical properties with the tensile strength of 24.1 MPa and the flexural strength of 41.9 MPa. References | Related Articles | Metrics

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Synthesis and Antibacterial Activities of Carboxylic Myrtanyl Esters LIAO Sheng-liang, SHANG Shi-bin, SI Hong-yan, SHEN Ming-gui, RAO Xiao-ping, SONG Zhan-qian 2015, 35 (6):  33-38.  doi: 10.3969/j.issn.0253-2417.2015.06.006 Abstract ( 891 )   PDF (1194KB) ( 752 )   Save Myrtanol was prepared via hydroboration-oxidation reaction from β-pinene, then eight novel carboxylic myrtanyl esters (myrtanyl acetate(4a), myrtanyl propionate(4b), myrtanyl butyrate(4c), myrtanyl valerate(4d), myrtanyl cyclohexanecarboxylate(4e), myrtanyl benzoate(4f), myrtanyl p-methylbenzoate(4g) and myrtanyl p-methoxybenzoate(4h) were obtained through the reaction of myrtanol and carboxylic acids using N, N'-dicyclohexylcarbodiimide/dimethylaminopyridine (DCC/DMAP) as catalyst.Structure characterizations were achieved by FT-IR, 1H NMR and ESI-MS.Antibacterial activity assays were carried out by agar dilution method.The results showed that compounds 4b, 4c, 4f, 4g and 4h exhibited inhibitory activities (MIC was 256 mg/L) against the Gram positive bacterial Staphylococcus aureus, and compounds 4a, 4b, 4c and 4e exhibited inhibitory activities (MICs were ranged from 128 to 256 mg/L) against the Gram negative bacterial Escherichia coli.more importantly.Compound 4a showed comparable activity (MIC was 128 mg/L) to that of bromogeramine against E.coli.Comparing with the starting compound β-pinene and the intermediate myrtanol, this series of esters showed better antibacterial activities. References | Related Articles | Metrics

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Synthesis and Properties of Rosin-based Gemini Surfactants with Amide Group SONG Bing-lei, YU Xiao-na, CHEN Yan, PEI Xiao-mei, ZHOU Ping-ping, ZHAI Zhao-lan 2015, 35 (6):  39-46.  doi: 10.3969/j.issn.0253-2417.2015.06.007 Abstract ( 766 )   PDF (15450KB) ( 596 )   Save Three novel rosin-based Gemini surfactants, i.e., 1, 6-bis(3-dehydroabietic amide-propyl-dimethyl ammonium bromide)hexane, 1, 8-bis(3-dehydroabietic amide-propyl-dimethyl ammonium bromide)octane and 1, 10-bis(3-Dehydroabietic amide-propyl-dimethyl ammonium bromide) decane (abbreviated to R-6-R, R-8-R and R-10-R), were synthesized from dehydroabietic acid via reactions of amidation and quaternization.The surface activities of three surfactants were investigated by surface tension and electric conductivity methods.And the results showed that the critical micelle concentrations (Ccmc) of R-6-R, R-8-R and R-10-R were 0.41, 0.39 and 0.24 mmol/L, and the minimum molecular occupation areas (Amin) were 1.00, 1.46 and 1.72 nm2, respectively.The amide groups in the hydrophobic chain promoted the adsorption of surfactants at the interface.The presence of a rigid rosin skeleton made this kind of surfactants have strong foam stability and emulsifying properties.The foam half-lives of R-6-R, R-8-R and R-10-R were 1 320, 1 200 and 1 050 min, respectively.And the emulsion remained stable after 7 days when the concentration of surfactant was only 0.3 mmol/L. References | Related Articles | Metrics

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Preparation of Salvianolic Acid B from Salvia miltiorrhiza Bunge by pH-Zone-refining Counter-current Chromatography LIU Hao, HANG Wei, CHEN Yi-lun, WANG Xiao, LIU Wei 2015, 35 (6):  47-52.  doi: 10.3969/j.issn.0253-2417.2015.06.008 Abstract ( 629 )   PDF (3486KB) ( 689 )   Save Salvianolic acid B, rosmarinic acid and methyl lithospermate were successfully separated from the roots of Salvia miltiorrhiza Bunge by pH-zone-refining high speed countercurrent chromatography in one step.The separation was performed with a two-phase system composed of petroleum ether-ethyl acetate-butanol-water(2:3:6:9, the volume ratio).The lower-phase was used as the mobile phase with a flow rate of 2.0 mL/min, the apparatus rotated at 850 r/min and the effluents were detected at 254 nm.Salvianolic acid B(1 419.15 mg), rosmarinic acid(171.25 mg) and methyl lithospermate(52.34 mg) were obtained from 6 g of the crude sample in one step.Their purities determined by high performance liquid chromatography(HPLC)were 94.53%, 96.36% and 96.83%, respectively.The structures of the target compounds was identified by electrospray ionization mass spectrometry(ESI-MS), 1H nuclear magnetic resonance (1H NMR) and 13C nuclear magnetic resonance (13C NMR). References | Related Articles | Metrics

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Effects of Rosin and Modified Rosin on Welding Performance of Sn0.7Cu Solder QI Fan, CAI Zhao-sheng, SHANG Shi-bin, HUANG Xu-juan 2015, 35 (6):  53-57.  doi: 10.3969/j.issn.0253-2417.2015.06.009 Abstract ( 1033 )   PDF (2057KB) ( 704 )   Save A series of liquid soldering fluxes were prepared with rosin, hydrogenated rosin, disproportionated rosin and polymerized rosin as active ingredient, respectively.The effects of these soldering fluxes on the wettabilities of Sn0.7Cu lead-free solder to the copper plate were investigated by using spreading ratio method.The comparative experiment of 810A type commercially available flux was tested as well.The physical performances of these soldering fluxes were tested and the appearance of soldered joints at the spreading ratio above 75% was analyzed.The results showed the spreading ratios increased gradually with the increase of the content of active ingredient.The acid value influenced the help welding ability of rosin markedly, and the sample with higher acid value showed better spreading ratio.When the contents of active ingredients were the same, the soldering flux obtained from rosin showed the best solder ability, then the hydrogenated rosin, disproportionated rosin and polymerized rosin in sequence.With the increasing of contents, the spreading ratios of rosin and modified rosin were higher than 70 %.This matched with the request of L level halogen-free rosin based flux of SJ/T 11389—2009.Except for polymerized rosin, the spreading ratios of rosin and modified rosin could get to 75% above in some contents.This matched with the request of M level flux of SJ/T 11389—2009.The physical stability, dryness and corrosivity to copper plate of these fluxes all met the standard, and the surface resistance (SIR) after welding concerned with the soldering flux was over 1.0×108Ω.Rosin showed better appearance of welding spot than the 810A flux. References | Related Articles | Metrics

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Effects of Ozone Pretreatment on the Enzymatic Hydrolysis Efficiency of Corn Stover LI Cheng, WANG Li, LI Yong-fu, WANG Ren, CHEN Zheng-xing 2015, 35 (6):  58-62.  doi: 10.3969/j.issn.0253-2417.2015.06.010 Abstract ( 892 )   PDF (982KB) ( 908 )   Save The corn stover was ozonolyzed and enzymatically hydrolyzed into fermentable sugar.The effects of ozone treatment on corn stovers with different particle sizes and moistures were studied.The optimum particle size and moisture content were determined.The results showed the corn stover with small particle size (< 48 μm) and moisture 60% was preferred for ozonolysis.The lignin content was decreased to 2.96% from 15.04% (raw) and saccharification rate was increased to 39.80% from 9.17% (raw).The effects of reaction time on ozonolysis under the optimum conditions were also investigated.The lignin was gradually degraded with the rising of ozonolysis time, and the saccharification rate was about 40.29% after 75 min.The strong linearity between ozone consumption and lignin degradation rate revealed that ozone mainly reacted with lignin, and resulted in the degradation of the lignin.Ozonolysis treatment could improve the hydrolysis of corn stover effectively. References | Related Articles | Metrics

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Synthesis and Characterization of Di-vinyl-terminated Rosin Derivatives under Microwave Irradiation LU Yan-ju, WANG Mi-xia, GU Yan, CHEN Yu-xiang, BI Liang-wu, ZHAO Zhen-dong 2015, 35 (6):  63-68.  doi: 10.3969/j.issn.0253-2417.2015.06.011 Abstract ( 686 )   PDF (2397KB) ( 719 )   Save Allyl acrylate-modified rosinate was synthesized by using sodium acrylic modified rosinate(SAMR) and allyl chloride as raw materials, cetyl trimethyl ammonium bromide as catalyst, hydroquinone as polymerization inhibitor(0.2% of the mass of SAMR) and N, N-dimetylformamide as solvent(treble the mass of SAMR) under microwave irradiation.The influence of different reaction conditions on the yield of product was investigated.The optimum reaction conditions were microwave energy 400 W, reaction time 100 min, catalyst amount 4%, molar ratio of allyl chloride and sodium acrylic modified rosinate 1:1, reaction temperature 50 ℃, and the yield was 92.2% under these conditions.The structure of the product was characterized by GC, GC-MS and FT-IR.The results showed that the structure of the synthesized product and the target product was consistent. References | Related Articles | Metrics

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Synthesis and Antifungal Activity of CamphoricAcid-based Thiourea Derivatives MA Xian-li, LIU Lu-zhi, DUAN Wen-gui, SHI Xian-chun, LI Fang-yao, HUA Zhong-ze 2015, 35 (6):  69-77.  doi: 10.3969/j.issn.0253-2417.2015.06.012 Abstract ( 840 )   PDF (1106KB) ( 731 )   Save Ten novel camphoric acid-based thiourea compounds (5a-5j) were prepared using camphoric acid and aminoethyl substituted phenyl thioureas as starting materials.The target compounds were characterized by FT-IR, 1H NMR, 13C NMR, LC-MS, and elemental analysis.The antifungal activities of the compounds 5a-5j were tested.The preliminary bioassay showed that most of the target compounds exhibited certain antifungal activities, in which camphoric acid-based (o-methoxy)phenyl thiourea 5c (R=o-CH3O) and camphoric acid-based (m-methoxy)phenyl thiourea 5d (R=m-CH3O) had inhibition rate of 86.9 % against Alternaria solani, and camphoric acid-based (m-methoxy)phenyl thiourea 5d, camphoric acid-based (m-methyl)phenyl thiourea 5g (R=m-CH3) and camphoric acid-based (p-bromo)phenyl thiourea 4i (R=p-Br) had inhibition rate of 86.1 % against Physalospora piricola at the concentration of 50 mg/L.In addition, compound 5i also had the best inhibitory activity against cercospora arachidicola(73.6%). References | Related Articles | Metrics

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Preparation of Polyurethane Foam from Liquefied Rice Straw WANG Wan-yu, WANG Dun, ZHANG Yu-cang 2015, 35 (6):  78-82.  doi: 10.3969/j.issn.0253-2417.2015.06.013 Abstract ( 710 )   PDF (983KB) ( 827 )   Save The rice straw was liquefied by using polyethylene glycol 400 and glycerol as mixed liquefier and concentrated sulfuric acid as catalyst.And this liquefied rice straw was employed to prepare the polyurethane (PU) foam, and followed by a characterization of its structure and performance.The effects of isocyanate index, water content, the proportion of the catalyst, and the amount of silicone oil on properties of the PU foam were studied.The results showed that the PU foam can be prepared with good properties by using the liquefied rice straw and isocyanate (PAPI) as raw materials, under the optimum condition, namely, 2% weight content of water against the mass of the liquefied rice straw, triethylenediamine and stannous octoate composite catalysts with the weight ratio of 0.1:0.3(g :g), 4% silicone oil as foam stabilizer against liquid agent and the isocyanate index of 1.2.And the properties of these PU foam i.e. the density, the tensile strength and the compressive strength were 35.78 kg/m3, 222.60 kPa, 110.90 kPa, respectively.TGA analysis indicated that rice straw-based PU foam had good heat resistance with the initial decomposition temperature of 241 ℃ and the most rapid decomposing temperature of 420 ℃. References | Related Articles | Metrics

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Synthesis and Properties of Hydrogenated Rosin Modified Vinyl Polysiloxane XU Tao, LIU He, SHANG Shi-bin, SONG Zhan-qian, YANG Chong 2015, 35 (6):  83-88.  doi: 10.3969/j.issn.0253-2417.2015.06.014 Abstract ( 692 )   PDF (1787KB) ( 661 )   Save Hydrogenated rosin (HR) modified vinyl polysiloxane (HR-VMS) was firstly synthesized from HR, hexamethyldisiloxane (MM), 1, 3, 5, 7-tetravinyl-1, 3, 5, 7-tetramethylcyclotetrasiloxane (D4Vi), octamethyl cyclotetrasiloxane (D4) and hydrolyzate of γ-aminopropyl(diethoxy)methylsilane (HAPMS).The novel resin (HR-VMS) was further characterized by 1H NMR, 13C NMR and FT-IR.The curing behavior of HR-VMS with 2, 5-bis(tert-butylperoxy)-2, 5-dimethylhexane(DBPH) as the curing agent was studied by differential scanning calorimetry (DSC).The low-temperature resistance and high-temperature thermal stability of the curing product were studied by DSC and TG, respectively.The results showed that at the heating rate of 10℃/min, the peak-top temperature of exothermic peak for HR-VMS was 186.9 ℃ with the exothermic value of 100.3 J/g.The curing product from HR-VMS showed better high-temperature thermal stability compared with VMS, and the temperature corresponding to its maximum weight loss rate was 436.1℃ which was 68℃ higher than that of common vinyl polysiloxane resin. References | Related Articles | Metrics

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Ethanol Production from Dilute Sulfuric Acid-calciumHydroxide Co-pretreated Corn Stover ZHU Yuan-yuan, YANG Jin-long, ZHU Jun-jun, ZHANG Lu, XU Yong, YONG Qiang, YU Shi-yuan 2015, 35 (6):  89-95.  doi: 10.3969/j.issn.0253-2417.2015.06.015 Abstract ( 876 )   PDF (1415KB) ( 760 )   Save Corn stover pretreated by dilute sulfuric acid and calcium hydroxide was used to produce fuel ethanol.The pre-hydrolyzate obtained from dilute sulfuric acid pretreated corn stover was mainly composed by xylose, which could be fermented to produce ethanol.The solid residue were further pretreated by calcium hydroxide and then hydrolyzated to glucose with cellulase for hexose fermentation.Based on this process, the glucose and xylose could be converted to ethanol, respectively.The optimal dilute sulfuric acid pretreatment could be obtained as the corn stover was pretreated by 1.00% sulfuric acid (based on dry corn stover), rat 130 ℃ for 70 min and the xylan hydrolysis yield was 80.45%.The ethanol yields of pentose fermentation of the unconcentrated, 1-fold concentrated and 2.5-folds concentrated pre-hydrolyzates by P.stipitis were 82.52%, 85.13% and 73.64%, respectively.The optimal further pretreatment with calcium hydroxide were conducted as the solid residues were treated by 0.125g/g calcium hydroxide (based on dry corn stover), at 90 ℃ for 24 h.The cellulose enzymatic hydrolysis yield was 84.92%.The hexose ethanol fermentation yields of the two-step pretreated residue enzymatic hydrolyzates of unconcentrated, 1-fold concentrated and 2-folds concentrated by S.cerevisiae were 92.22%, 91.89% and 85.54%, respectively. References | Related Articles | Metrics

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A Method Based on Near Infrared Spectra for Rapid Identification of Wood Genuses and Species CUI Hong-hui, FANG Gui-gan 2015, 35 (6):  96-100.  doi: 10.3969/j.issn.0253-2417.2015.06.016 Abstract ( 698 )   PDF (1896KB) ( 732 )   Save The identification of eucalyptus and acacia wood and classification among six kinds of wood were studied in this paper, based on near-infrared spectroscopy method combined with chemometrics algorithm.Firstly, near-infrared spectra of 86 samples, containing Eucalyptus urophylla×E. grondis, E.urophylla L11, E.urophylla U6, E.globules, Acacia mangium and A.crassicarpa.were collected, Then partial least squares discriminant analysis (PLS-DA) was used to establish a classification model of eucalyptus and acacia.The results showed that the regression lines between predicted value and actual value of calibration set and validation set were in good agreement, and the coefficient of determination (R2) were 0.99 and 0.97.This showed that the model was better.Moreover, the accuracy of the unknown samples was 100%.MSC and Savitzky-Golay smoothing method were used to pretreat the spectral of 4000-7500 cm-1, and discrimination model was established based on the principal component analysis(PCA).Results showed that the recognition rate of the calibration and validation model was 100%.Therefore, the chemometrics algorithm based on near infrared spectra could identify the eucalyptus and acacia species quickly. References | Related Articles | Metrics

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Separation of Fisetin from Toxicodendron vernicifluum (Stokes) F.A.Barkl.Woods and Its Anti-tyrosinase Activity CHEN Hong-xia, WANG Cheng-zhang, YE Jian-zhong, ZHOU Hao, TAO Ran 2015, 35 (6):  101-107.  doi: 10.3969/j.issn.0253-2417.2015.06.017 Abstract ( 780 )   PDF (3922KB) ( 809 )   Save The Toxicodendron vernicifluum (Stokes) F.A.Barkl.woods were extracted with 70 % ehanol by decompressing inner ebullition method.The compound with the purity over 70 % was obtained through the extraction by rapid isolation of extracts with ethyl acetate and middle pressure chromatography.Then the compound was separated by HPLC to obtain monomeric compound.The compound was identified as fisetin by IR, MS and NMR.The inhibitories of fisetin on the activities of monophenolase and diphenolase contained in tyrosinase were studied.The results showed that fisetin could potently inhibit the generation of dopachrome.The half inhibitory concentration of monophenolase was 69.46 mg/L.The inhibitory of fisetin against monophenolase exhibited retardation effect.Fisetin with0.524 mmol/L could extend the lag time from 1 min to 11.2 min.Fisetin functioned as a competitive inhibitor against diphenolase by Lineweaver-Burk plots. References | Related Articles | Metrics

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Breeding of Robust Inhibitor-tolerant Industrial Saccharomyces cerevisiae Strain by Genomic DNA Mutagenesis CHEN Liang, XU Long-long, YAN De-ran, DU Feng-guang, HUI Feng-li 2015, 35 (6):  108-112.  doi: 10.3969/j.issn.0253-2417.2015.06.018 Abstract ( 617 )   PDF (1219KB) ( 664 )   Save The recombinant Saccharomyces cerevisiae HN-1-24 was obtained by combination of chemical mutagenesis and genomic DNA mutagenesis-based genetic recombination methods to improve the inhibitor tolerance and fermentation performance.The recombinant strain HN-1-24 exhibited a high conversation rate of sugar to ethanol and ethanol production under a condition with 7 g/L acetic acid and 1 g/L furfural.Thus 38 g/L of ethanol could be obtained from 100 g/L of glucose.When ethanol fermentation of cellulose hydrolyzate culture was performed, the fermentation time of the recombinant strain was decreased by 6 h and the final ethanol concentration was enhanced by 8.8% as compared with the original strain.The results of this study provided a basis for the large-scale production of fuel ethanol by using lignocellulose. References | Related Articles | Metrics

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Influence of Cellulase and Hemicellulase Modification on Pulp Performance of Bleached Softwood Fiber DU Min, LI Xin-ping, CHEN Li-hong, WANG Zhi-jie, LI Hong-kui 2015, 35 (6):  113-118.  doi: 10.3969/j.issn.0253-2417.2015.06.019 Abstract ( 724 )   PDF (1364KB) ( 626 )   Save Complex cellulase, endo-cellulase and xylanase were applied to modify bleached softwood fiber (BSF).The influences of three enzymes on the performance of pulp were investigated.The results indicated that complex cellulase had the biggest influence on the performance of BSF among three enzymes.With the dosage of complex cellulase increasing, the pulp drainability first increased and then decreased.Both of water retention value (WRV) and the absolute value of Zeta potential decreased first and then increased.The hydrophilic of fiber surface reduced; the fiber length declined sharply; and the tensile index of hand-sheet increased first and then declined sharply. In the dosage of 5.0 U/g, compared with the sample without modification, the average fiber length was declined by 48.64%, and the tensile index of hand-sheet decreased by 23.23%. The effects of endo-cellulase and xylanase on the pulp were relatively small.After modification by these two enzymes, both of WRV and the absolute value of Zeta potential decreased gradually, but the hydrophilic of fiber surface and the tensile index of hand-sheet increased slowly.Endo-cellulase had the best modification effect for the paper industry.When the dosage of endo-cellulase was 5.0 U/g, the hydrophilic of fiber surface increased.It was beneficial for fiber refining and the tensile index of hand-sheet increased to 22.04 N·m/g by 20.77% compared with the sample without modification. References | Related Articles | Metrics

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Thermal Stability and Decomposition Kinetics of Oridonin by Thermal Analysis Method LIU Jian-qun, GAO Jun-bo, LIU Xiao-hong 2015, 35 (6):  119-125.  doi: 10.3969/j.issn.0253-2417.2015.06.020 Abstract ( 1038 )   PDF (1935KB) ( 642 )   Save Thermal decomposing curves of oridonin at different heating speeds were obtained in the nitrogen atmosphere by TG-DTG and DTA-DDTA techniques to study the thermal stability, decomposition kinetics, and shelflife of oridonin under the heat condition.Four thermal analysis kinetic methods (Kissinger, Ozawa, Coats-Redfern and Achar) were used to speculate the probable mechanism of thermal decomposing reaction and the kinetic parameters including activation energy Ea and pre-exponential factor A.The shelflife of oridonin at room temperature (25℃) was calculated by the kinetic parameters of the first stage.With the increase of the heating rate, thermal decomposing tempreture of oridonin rose.The TG curve showed the decomposition of oridonin could be divided into two steps.The first weight loss rate was 84.8% from 206.4 ℃ to 493.0 ℃ and the second weight loss rate was 15.2% from 493.0 ℃ to 669.6 ℃.The DTA and DDTA curves showed an endothermic peak at about 249℃ and an exothermic peak at about 675℃.The most probable kinetic mechanisms of the first stage thermal decomposition were three-dimensional diffusion and the corresponding mechanisms followed Zhuralev-Lesokin-Tempelman Equation.The average apparent activation energy(Ea) was 145.95 kJ/mol and the pre-exponential factor(A) was 4.87×1010 min-1.The theoretical shelflife of oridonin at room temperature was about 4-5 years. References | Related Articles | Metrics

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Extraction of Essential Oil from the Flower of Chionanthus retusus Lindl.et Paxton by Supercritical CO2 and Its Antibacterial Activities LIU Pu, LI Xiao-fang, GAO Jia-yu, YIN Wei-ping, DENG Rui-xue 2015, 35 (6):  126-132.  doi: 10.3969/j.issn.0253-2417.2015.06.021 Abstract ( 808 )   PDF (1426KB) ( 709 )   Save Single factor experiment and orthogonal experiment design were used to study the influences of extraction conditions on the yield of essential oil from the flower of Chionanthus retusus Lindl.et Paxton by supercritical CO2 method.The components of the essential oil were analyzed by gas chromatography-mass spectrometry (GC-MS).The in vitro antibacterial activity of the eessential oil was characterized.The optimum extraction parameters were established with the extraction pressure 25 MPa, extraction temperature 45 ℃, extraction time 2.0 h, and the fluent of CO2 22 kg/h.The yield of essential oil was up to 0.409%.Sixty compositions were separated.Among them, 57 components were identified and respresented 96.18% of the total detected constituents.The results of the antibacteria, i.e., assay showed that the essential oil displayed good antibacterial activity against the tested bacterial, i.e. Staphyloccocus aureu, Staphyloccocus albus, Escherichia coli. References | Related Articles | Metrics

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Screening, Separation and Purification of Mulberry Leaf Polyphenols ZHOU Hao, LI Wen-jun, ZHANG Jun, ZHANG Yu-si, YAN Xin-pei, WANG Cheng-zhang 2015, 35 (6):  133-140.  doi: 10.3969/j.issn.0253-2417.2015.06.022 Abstract ( 742 )   PDF (1259KB) ( 744 )   Save Ultrasonic-microwave combined technology was used to extract polyphenols from the mulberry leaves and Folin-Ciocalte method was applied to analyze the content of polyphenols in different types and parts of mulberry leaves.The single factor and response surface methodology were successfully used to optimize the extraction conditions.Furthermore, the purification effects of different macroporous resins on the polyphenols were analyzed.The results showed that the highest content of polyphenols was 2.072 % from the type of Damodou, and the polyphenols content of Feng 24×Miao 33 was the lowest(1.035%) among eighteen varieties of mulberry leave.The optimal extraction conditions were 1 g Hu-sang87, liquid to solid ratio 20:1(mL:g), the extraction time 93 s, microwave power 326 W, ultrasonic power 304 W.Meanwhile, the yield of crude extracts was 1.598 % and the purity was 10.87 %.The most suitable resin for this purification was H103 with adsorbing capacity of 15.57 mg/g, desorption ratio of 88.67 % and short adsorption and desorption equilibrium time.The best adsorbing condition of polyphenols sample solution were adsorption column volume 40 mL, loading quantity of 15 g crude extract, mass concentration 3 g/L and the best elution conditions were ethanol volume fraction 60 %, flow rate 2 mL/min, elution volume 80 mL.Then, the purity of polyphenol increased from 10.87 % to 65.45 % under these conditions, and in the process of purification, the total yield was 84.7 %. References | Related Articles | Metrics

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Research Advances about Hemicelluloses Distribution in Plant Cell Wall MA Jing, ZHANG Xun, ZHOU Xia, JI Zhe, XU Feng 2015, 35 (6):  141-147.  doi: 10.3969/j.issn.0253-2417.2015.06.023 Abstract ( 1017 )   PDF (991KB) ( 962 )   Save The depletion of fossil resources globally spurred on the research for the high-value utilization of the three main components of biomass.Ongoing research is worldwide focusing on the location of hemicelluloses in plant cell wall due to its tight bounding with the cellulose and the chemical bonds formation with lignin in plant cell wall.The present review mainly summarized three techniques for displaying the micro-distribution of hemicelluloses in plant cell wall, namely traditional histochemistry, spectral microscopy and immunocytochemistry in recent 50 years according to the developing path of technologies.The particular analysis methods of every technique were analyzed, the deficiency of traditional technology was pointed out and the research direction of hemicelluloses was forecasted. References | Related Articles | Metrics

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Research Progress on Preparation Methods and Applications of Dextran-based Hydrogels LIN Yan, FANG Gui-gan, HUO Dan 2015, 35 (6):  148-152.  doi: 10.3969/j.issn.0253-2417.2015.06.024 Abstract ( 853 )   PDF (836KB) ( 922 )   Save As a kind of biological polysaccharide, dextran contains many free hydroxyl groups on the main chain, which is convenient for modification and crosslinking.The hydrogels prepared by dextran exhibited excellent swelling property, biocompatibility and biodegradability.Dextran is widely applied in the fields of substance separation, drug delivery and tissue engineering.Kinds of common preparation methods of dextran-based hydrogels, including repeated freezing-thawing method, chemical crosslinking method, grafting modification method, and free radical polymerization, have been summarized, Besides, the applications of dextran-based hydrogels in recent years are reviewed and the future developments are discussed in present study. References | Related Articles | Metrics

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Progress on Reaction Pathway and Catalysts for Preparation of Long Chain Alkanes from Lignocellulosic Biomass CAI Chi-liu, LIU Qi-ying, WANG Tie-jun, ZHANG QI, MA Long-long, SHI Ning, TAN Jin, LI Kai 2015, 35 (6):  153-162.  doi: 10.3969/j.issn.0253-2417.2015.06.025 Abstract ( 778 )   PDF (2450KB) ( 810 )   Save This paper summarized the multi-step synthetic routes of long chain alkanes from lignocellulosic biomass.Firstly, the key platforms were obtained from the hydrolysis of lignocellulose.Then, the corbon chain growthes of platforms were conducted by aldol condensation, hydroxyalkylation, ketonization, self-coupling, and so on.Finally, the long chain alkanes were obtained from the intermediates by hydrodeoxygenation. The depolymerization of biomass to platforms, the pathways and product distributions depended on platform coupling modes.The hydrodeoxygenation of intermediates to final hydrocarbons was elucidated.The relative solid catalysts in stepwise conversion were also discussed.Finally, the state-of-the-art technologies for biomass derived long chained hydrocarbons were concluded and prospected. References | Related Articles | Metrics