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28 April 2014, Volume 34 Issue 2 Previous Issue    Next Issue

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Preparation and Characterization of Amine Grafted SBA-15 Catalysts and Their Application in Aldol Condensation Reaction REN Hong-qing, XIE Jian-jun, LIU Hua-cai, YIN Xiu-li, WU Chuang-zhi 2014, 34 (2):  1-8.  doi: 10.3969/j.issn.0253-2417.2014.02.001 Abstract ( 719 )   PDF (3414KB) ( 823 )   Save Solid basic catalysts were synthesized by post-grafting four different organic amines, i.e. primary amine(PA), secondary amine(SA), tertiary amine(TA) and piperazidine(PP) to mesoporous SBA-15.The samples were characterized by X-ray diffraction, nitrogen adsorption, thermogravimetric analysis, scanning electron microscopy and elemental analysis. The activity of prepared catalysts was tested in aldol condensation reaction of bio-oil model compounds (furfural and acetone). The influence of graft reaction conditions, different functional groups of amine, solvents and temperature on conversion of furfural and selectivity of FA and F2A were investigated. The results indicated that the prepared samples retain excellent ordered mesoporous structure with the amino loading at 0.6-1.0 mmol/g. The catalytic activity increased when strict N2-pretected grafting condition, protic solvent and higher temperature were used. The catalyst containing primary amine (N2-pretected grafting condition) shows the best catalytic activity. The highest conversion of furfural (82.6%) and product selectivity of FA (41.4%) and F2A(8.7%) can be achieved after reaction at 80 ℃ for 8 h in H2O solvent. References | Related Articles | Metrics

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Extended Study of Sunflower Straw in the Selective Adsorption Behaviors and Mechanisms for U(VI) and Pb(Ⅱ) AI Lian, LUO Xue-gang, LIN Xiao-yan, MEI Qiang 2014, 34 (2):  9-16.  doi: 10.3969/j.issn.0253-2417.2014.02.002 Abstract ( 651 )   PDF (3429KB) ( 699 )   Save The adsorptive properties of sunflower straw for U (VI) and Pb (Ⅱ) were systematically evaluated in single and binary solutions using batch experiments as a function of solution pH, adsorbent dosage, contact time and initial ion concentration. The kinetic data were analyzed by the pseudo-first-order, pseudo-second-order kinetic and intraparticle diffusion models. The equilibrium sorption data were examined using the Langmuir and Freundlich isotherm equations. It was shown that that a dose of 2.0 g/L of sunflower straw in an initial ions concentration of 20 mg/L with an initial pH of 4.0 and a contact time of 720 min resulted in the maximum U (VI) and Pb (Ⅱ) removal efficiency (about 77.55% and 87.44%, respectively) in U (VI)/Pb (Ⅱ) binary system. The kinetic and isotherm experimental data were fitted to the pseudo-second-order rate equation and the Langmuir isotherm model with much satisfaction for single and binary metal systems, respectively. The sorption data of Pb (Ⅱ) also conformed successfully to the Freundlich equation at U (VI) concentration more than 200 mg/L. The maximum adsorption capacity in single system for U (VI) and Pb (Ⅱ) was calculated to be 327.0 and 67.59 mg/g, respectively. The sunflower straw displayed an excellent selectivity in the adsorption of Pb (Ⅱ) over U (VI) in the binary system at lower initial concentrations of ions and the case was vice versa at higher concentrations. Furthermore, SEM, EDX and FT-IR analyses revealed that U (VI) and Pb (Ⅱ) adsorption onto sunflower straw could be predominantly controlled by the ion exchange as well as complexation mechanism. References | Related Articles | Metrics

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Preparative Isolation and Purification of Flavonoids from the Flower of Chrysanthemum morifolium Ramat. by High-speed Counter-current Chromatography PAN Shao-bin, YU Zong-yuan, WANG Xiao, ZHAO Jin, GENG Yan-ling, LIU Jian-hua, DUAN Wen-juan 2014, 34 (2):  17-22.  doi: 10.3969/j.issn.0253-2417.2014.02.003 Abstract ( 749 )   PDF (1107KB) ( 699 )   Save High-speed counter-current chromatography (HSCCC) method for isolation and purification of flavonoids crystalloid, i.e. apigenin-7-O-rutinoside(I), luteolin-7-O-glucoside(Ⅱ), apigenin-7-O-glucoside(Ⅲ) and acacetin-7-O-glucoside(IV) from Chrysanthemum morifolium Ramat. was established successfully. The separation was performed in two steps with two different types of solvent systems: ethyl acetate-ethanol-water-acetic acid (4:1:5:0.2, v/v) and chloroform-methanol-water (4:3:2, v/v). In the first separation step, 100 mg of the flavonoids crystalloid yielded 11.2 mg of apigenin-7-O-rutinoside, 15.3 mg of luteolin-7-O-glucoside, and 28.2 mg of apigenin-7-O-glucoside. Then we collected tail blowing fluid and obtained 35 mg of extract by evaporation to dryness. In the second step, when we used [chloroform-methanol-water (4:3:2, v/v)] solvent system to separate the 35 mg of extract, 14.5 mg of acacetin-7-O-glucoside could be obtained. Their four compounds purities were 99.4%, 93.6%, 99.1% and 99.5%, respectively. Their structures were identified by ESI-MS, 1H NMR, and 13C NMR. References | Related Articles | Metrics

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Chemical Structure and Thermochemical Property of Lignin Sulfonate LI Ji-biao, WU Shu-bin, XU Shao-hua 2014, 34 (2):  23-28.  doi: 10.3969/j.issn.0253-2417.2014.02.004 Abstract ( 1070 )   PDF (1791KB) ( 929 )   Save Calcium lignosulfonate (Ca-Ls) was selected as the raw material. Its chemical structure and property were characterized by means of elemental analysis and Fourier transform infrared spectroscopy (FT-IR). The pyrolysis characteristics were also analyzed by thermal gravimetric analysis (TG) and pyrolysis-gas chromatography combined with mass spectrometry (Py-GC/MS). The results showed that: 1) Ca-Ls had a lower carbon and nitrogen content and higher sulfur content than lignin from herbal wood; 2) Ca-Ls contained rich guaiacyl (G-type) and syringyl (S-type) structure unit; 3) the pyrolysis of Ca-Ls was divided into four stages, and the main pyrolysis temperature range was 150-450 ℃; 4) when heating rate was 10, 20 and 30 ℃/min, the biggest weight loss peak on the DTG curves migrated to higher temperature, meanwhile, as the heating rate increased, the response time for sample particles to reach the desired pyrolysis temperature became shorter. Thus the thermal decomposition rate increased and the process of thermal decomposition of Ca-Ls was changed. References | Related Articles | Metrics

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Synthesis of Highly Dispersed Fibrous Mesoporous γ-Al2O3 with Rosin-based Quaternary Ammonium Salt WANG Peng, ZHAO Zhen-dong, XU Li-feng, BI Liang-wu, WANG Zong-de 2014, 34 (2):  29-32.  doi: 10.3969/j.issn.0253-2417.2014.02.005 Abstract ( 711 )   PDF (2690KB) ( 678 )   Save Highly dispersed mesoporous alumina fibers were successfully synthesized through urea hydrothermal-uniform precipitation method using rosin-based quaternary ammonium salt as a structure directing agent. Their structures were characterized with X-ray diffraction, N2 adsorption and desorption, field-emission scanning electron microscope and transmission electron microscope. The results indicated that well dispersed fibrous ammonium aluminium carbonate hydroxide precursors were formed under the hydrothermal treatment. After the calcinations at 823 K for 4 h, fibrous mesoporous γ-Al2O3 were obtained. The temperatures of the hydrothermal treatments had significant influence on the textural properties of the samples. The increase of the temperatures resulted in the increase of crystallinities. However, after the calcinations, all the samples transformed into γ-Al2O3 phase. No distinct difference of crystal structure could be observed among the samples. When the hydrothermal temperature was 373 K, the sample possessed a larger surface area (241.18 m2/g) with a smaller pore diameter(7.21 nm). The increase or decrease of the hydrothermal temperatures led to the decrease of surface areas, and the increase of pore diameters. The length of the precursor fibers was about 5 μm, and the width of which was about 200 nm. After the calcinations, the morphology of the sample kept intact with porocity increased. References | Related Articles | Metrics

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Thermal Decomposition Mechanism and Kinetics of Ursolic Acid and Caffeic Acid XIAO Zhuo-bing, GUO Man-man, GUO Rui-ke 2014, 34 (2):  33-39.  doi: 10.3969/j.issn.0253-2417.2014.02.006 Abstract ( 1142 )   PDF (1485KB) ( 831 )   Save Two kinds of natural organic acid, ursolic acid and caffeic acid were analyzed under the nitrogen atmosphere by thermogravimetry combined fourier transform infrared spectroscopy (TG-FT-IR). Experimental data of TG were computationally processed by three kinds of thermal analysis kinetics methods (Coats-Redfern, Achar and Malek methods), through which the most probable mechanisms and functions of each stage were inferred and the values of apparent activation energy Ea and pre-exponential factor A were also obtained. The results showed that according to percentage of weight loss, molecular simulation and infrared spectrum of evolved gases, the cracking of chemical bonds was confirmed. Thermal decomposition of ursolic acid began at 236.8 ℃ and ended at 431.2 ℃ with a complete mass loss while after 153.0 ℃ caffeic acid underwent the two-stage thermal decomposition. The most probable mechanisms of ursolic acid and caffeic acid at the first stage and the second stage were two-dimension diffusion, two-dimension diffusion and three-dimension diffusion, corresponding with Valensi equation, Jander equation and Z.-L.-T. equation, respectively. Ea of ursolic acid and caffeic acid at first stage and second stage were 228.26, 111.28 and 231.75 kJ/mol while their lnA were 39.56, 25.78 and 43.50, respectively. According to kinetic parameters, shelflives of ursolic acid and caffeic acid at 25 ℃ were 4-5 years and 3 years, respectively. References | Related Articles | Metrics

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Synthesis, Characterization and Polymerization Activity of Flexible Monomer Derived from Dehydroabietic Acid YU Juan, WANG Chun-peng, DING Li-na, CHEN Meng-yao, LIU Yu-peng, FU Li, CAI Zhi-hui, WANG Ji-fu, CHU Fu-xiang 2014, 34 (2):  40-44.  doi: 10.3969/j.issn.0253-2417.2014.02.007 Abstract ( 778 )   PDF (1420KB) ( 782 )   Save (2-amethcryloyloxy)hexyl ester of dehydroabietic acid (DA-2-HHMA) with a yield of 41% was synthesized by the reaction of dehydroabietic chloride (DA-Cl) with hexanediol, and subsequently with methacryloyl chloride. The resulting product was then characterized by using FT-IR spectroscopy, 1H NMR 13C NMR, DSC and GPC. The results showed that DA-2-HHMA could polymerize in the presence of initiator. The molecular weight of homompolymer is about 20 000-30 000 and its glass transition temperature is around -21.82 ℃. References | Related Articles | Metrics

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Effects of the Molecular Sieve 5A and APP on the Flame Retardance and Smoke Suppression in Wood by Cone Calorimeter CHEN Xun, YUAN Li-ping, HU Yun-chu, TIAN Liang-cai, WANG Jie, XIA Liao-yuan 2014, 34 (2):  45-50.  doi: 10.3969/j.issn.0253-2417.2014.02.008 Abstract ( 694 )   PDF (2705KB) ( 735 )   Save The effect of molecular sieve 5A and ammonium polyphosphate (APP) on the flame retardance and smoking-gas absorption in wood during the combustion process was investigated by cone calorimeter. The results showed that when APP was used as sole flame retardant, the total heat release (THR) reduced by 47.56% while mean yield of CO (mean-COY) increased by 185.71%. The application of molecular sieve 5A was found to have an inferior flame retardant efficiency. THR decreased by 16.86% through it. However, when 5A molecular sieve and APP was combined and used as flame retardant for wood, THR, total smoke production (TSP) and mean-COY reduced by 34.23%, 76.07% and 68.33%, respectively. CO, a representative toxic, was converted into CO2 by the use of 5A molecular sieve as catalyst. Thus the generation and release of toxic gas reduced. In short, high efficiency of flame retardance and smoke suppression in wood can be achieved when the flame retardants of 5A molecular sieve and APP were coused together. Thus the casualties in the fire were reduced. References | Related Articles | Metrics

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Tackifying Effect of Sweetgum Resin in SIS Hot Melt Adhesive XING Zhen-zhen, WU Wei-qian, ZENG Tao 2014, 34 (2):  51-55.  doi: 10.3969/j.issn.0253-2417.2014.02.009 Abstract ( 937 )   PDF (1542KB) ( 611 )   Save This article introduced the tackifying effect of Chinese sweetgum resin in styrene-three block copolymer of styrene isoprene-(SIS) hot melt adhesive (HMA). At the same time, the influence of some factors including the content, softening point, and the mixture ratio with terpene resin produced on the appearance, tack, retained adhesion, softening point, peeling strength, and glass-transition temperature of hot melt adhesive were discussed. The results showed that with the increase of content of sweetgum resin, the glass-transition temperature became high, the tack and 180°peeling strength increased firstly and then decreased and the retained adhesion decreased. The mixture of sweetgum resin of low-middle temperature could make the bonding better, and blending of different kinds of resins can achieve better adhesion properties. Under the condition of m(SIS):m(naphthenic 4010):m(tackifying resin):m(antioxidants)=38%:32%:30%:0.5%,including m(92℃sweetgum resin):m(94℃terpene resin)=2:1, hot melt adhesive had transparent appearance with no residue phenomenon, and the comprehensive performance of hot melt adhesive is the best. At the condition, the tack is 14#, peeling strength is over 600 N/m, and retained adhesion is over 72 h. References | Related Articles | Metrics

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Wheat Straw Biorefinery by Organic Acids (I) —Reaction Characteristics of Complex Organic Acids and Wheat Straw at Atmospheric Pressure FU Yu, YUAN Mei-ting, ZHAI Hua-min 2014, 34 (2):  56-60.  doi: 10.3969/j.issn.0253-2417.2014.02.010 Abstract ( 840 )   PDF (1502KB) ( 542 )   Save Biorefinery process by organic acids is a potential way to utilize wheat straw effectively. The influences of reaction temperature and time on the dissolutions of the wheat straw chemical components in formic acid-acetic acid-water organic acids (FAWOA) at atmospheric pressure were investigated in present study. The results indicated that the delignification process can be divided into three phases, namely a bulk phase, a complementary one and a residual one, with lignin removal by 37.1%, 27.2% and 2.50% respectively. The dissolution of pentosan also demonstrated as three stages, i.e., a bulk one, a complementary one and a residual one, with the dissolution ratios of 50.0%, 24.9% and 3.20% respectively. The removal of holocellulose, benzene-ethanol and ash can be divided into similar three phases as the removal of lignin and pentosan. The increasing trend of organic matter content in black liquor was similar to that of lignin and pentosan. However, only a slight variation of inorganic matter content was observed and represented a constant level at 2.0 g/L in the biorefinery process. References | Related Articles | Metrics

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Application of Amphoteric Cassava Dregs in ONP and Its Impacts on Retention, Drainage and Paper Physical Strength LIU Wen-jing, WU Shu-bin, TAO Zheng-yi 2014, 34 (2):  61-66.  doi: 10.3969/j.issn.0253-2417.2014.02.011 Abstract ( 635 )   PDF (1874KB) ( 626 )   Save The carboxymethylation pretreated cassava dregs grafted acrylamide and [2-methacryloyloxy] trimethylammonium chloride(CMPCD-g-AD)was used in deinked pulp. The effects of the factors, including CMPCD-g-AD dosage, pH value, conductivity, and shearing force, on the retention, pulp drainage and handsheet physical properties were studied in this study. The results showed that the optimal retention and drainage could be obtained as the dosage of CMPCD-g-AD is 1.2%, and the maximum value of drainage and first pass the retention (FPR) of recycled pulp is 244.6 g in 60 s and 90.46%, respectively. The best pulp retention was acquired at pH 8.5, and it decreased as the pH value was over 8.5. Hence, the CMPCD-g-AD was suitable for applying in a nearly pH-neutral solution. The increasing of salt content had a adverse effect on drainage and the fines retention decreased slightly by 3.8%. Shear force was negative for FPR, therefore, outlet of screen was proposed to be the point for adding CMPCD-g-AD. CMPCD-g-AD showed a significant positive impact on paper strength. The tensile index, burst index, tear index and breaking length were increased by 104.38%,12.77%,12.95% and 88.58%, respectively. References | Related Articles | Metrics

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Effect of Ultrasonic Treatment on Physicochemical Properties of Sodium Lignosulfonate ZHOU Bao-wen, HA Cheng-yong, DENG Lian-li, MO Jian-qiang, SUN Chun-ning, SHEN Min-min 2014, 34 (2):  67-72.  doi: 10.3969/j.issn.0253-2417.2014.02.012 Abstract ( 768 )   PDF (1652KB) ( 768 )   Save Sodium lignosulfonate (LS) was treated directly by ultrasonication. The effects of ultrasonication time, power and pH on the sodium lignosulfonate were studied in present study. The physicochemical properties of sodium lignosulfonate (LS) and sodium lignosulfonate treated with ultrasonication (ULS) were investigated by UV, FT-IR, 1H NMR and TGA. The application of ultrasonication on sodium lignosulfonate for different time (15, 45, 60 and 120 minutes) resulted in the increment of phenolic hydroxyl to 0.71%, 0.74%, 0.81% and 0.84% from 0.65%, respectively.Ultrasonication was applied to 10 g sodium lignosulfonate that dissolved in 100 mL distilled water. With the ascending powder of ultrasonication from 100 to 300 W, phenolic content of sodium lignosulfonate increased from 0.69% to 0.92%. The pH exhibited the most noticeable effect on the ultrasonication. Phenolic content reached to 1.58% as the pH was 0. FT-IR, UV and 1H NMR showed that ultrasound might cause partial disruption of aromatic rings and sulfonic acid groups of sodium lignosulfonate. TG analysis illustrated that ultrasonication had a complex influence on thermal ability of sodium lignosulfonate due to the simultaneous degradation and cross linking reactions. When sodium lignosulfonate aqueous solution was treated by ultrasonication (300 W, 20 kHz) for 60 min, degradation had an disadvantageous effect on the thermal stability of ULS between 200-600 ℃. However, when sodium lignosulfonate aqueous solution (pH=0,adjusted by concentrated sulfuric acid) was treated by ultrasonication (150 W, 40 kHz) for 60 min, ULS showed that the better one was over 680 ℃ because of the cross linking reactions. References | Related Articles | Metrics

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Preparation of 5-Hydroxymethylfurfural by Dehydration of Sucrose KONG Shan-shan, LIU Shi-wei, LI Lu, YU Shi-tao 2014, 34 (2):  73-76.  doi: 10.3969/j.issn.0253-2417.2014.02.013 Abstract ( 892 )   PDF (920KB) ( 729 )   Save The preparation of 5-hydroxymethylfurfural (HMF) from sucrose was studied in the presence of Brönsted-Lewis composite catalytic system. The effects of reaction conditions on the yield of 5-hydroxymethylfurfural were examined. The optimal reaction conditions were obtained as follows: sucrose 2.0 g, composite catalytic system HCl-CrCl3(mass ratio 5:1) 0.8 g, dimethyl sulfoxide 20 mL, reaction time 30 min and reaction temperature 200 ℃. Under the above conditions, the conversion of sucrose was 100%, and the yield of 5-hydroxymethylfurfural reached 72.7%. Moreover, CrCl3 had a good stability on the product 5-hydroxymethylfurfural. It could avoid 5-hydroxymethylfurfural over-reacting to form formic acid and levulinic acid by the hydration/decarboxylation reaction to a certain extent. References | Related Articles | Metrics

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Synthesis and UV Property of Rosin-derived Azo Compounds YAO Gui-yang, LIN Ning, DAI Wei-long, WEI Jing-chen, PAN Ying-ming, WANG Heng-shan 2014, 34 (2):  77-84.  doi: 10.3969/j.issn.0253-2417.2014.02.014 Abstract ( 783 )   PDF (1922KB) ( 638 )   Save Starting from methyl dehydroabietate, eight rosin-derived azo compounds were synthesized by nitration, reduction, diazonization and coupling reaction. The structures of eight azo compounds (1R,4aS)-methyl 6-((E)-(4-(dimethylamino)phenyl)diazenyl)-7-isopropyl-1,4a-di-methyl-8-nitro-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (2a), (1R,4aS)-methyl-6-((E)-(5-cyano-2-hydroxy-1,4-dimethyl-6-oxo-1,6-dihydropyridin-3-yl)diazenyl)-7-isopropyl-1,4a-dimethyl-8-nitro-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (2b), (1R,4aS)-meth-yl-((E)-(5-cyano-1-ethyl-2-hydroxy-4-methyl-6-oxo-1,6-dihydropyridin-3-yl)diazenyl)-7-isopropyl-1,4a-dimethyl-8-nitro-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (2c), (1R,4aS)-methyl-7-((E)-(4-(dimethylamino)phenyl)diazenyl)-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (3a), (1R,4aS)-methyl-7-((E)-(2-hydroxynaphthalen-1-yl)diazenyl)-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (3b), (1R,4aS)-methyl-7-((E)-(4-(dimethylamino)phenyl)diazenyl)-1,4a-dimethyl-9-oxo-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (5a), (1R,4aS)-methyl-7-((E)-(2-hydroxynaphthalen-1-yl)diazenyl)-1,4a-dimethyl-9-oxo-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (5b) and (1R,4aS)-methyl 6-bromo-7-((E)-(2-hydroxynaphthalen-1-yl)diazenyl)-1,4a-dimethyl-9-oxo-1,2,3,4,4a,9,10,10a-octahydrophenanthrene-1-carboxylate (5c) were characterized by MNR, IR and elemental analysis. The yields were 57%, 33%, 30%, 36%, 39%, 39%, 40% and 38%, respectively. Comparing with methyl dehydroabietate, their UV maximum absorption wavelength were 420, 454, 457, 541, 493, 549, 482 and 550 nm in chloroform, which were increased 200, 234, 237, 321, 273, 329, 262 and 330 nm, respectively. References | Related Articles | Metrics

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Influences on the Effect of Pretreating Cellulose by Pretreatment Solvents GUO Jing, XIE Piao, GUAN Fu-cheng, WANG Zhi-chao, ZHANG Cheng-jiao 2014, 34 (2):  85-90.  doi: 10.3969/j.issn.0253-2417.2014.02.015 Abstract ( 657 )   PDF (1736KB) ( 760 )   Save Acetone(CH3COCH3)/NaOH, ethanol(EtOH)/NaOH and other chemical reagents systems were used for pre-treating cellulose. The R-10 value and water retention value (VWR) were measured to evaluate their impacts on polymerization degree and accessibility of cellulose. The cellulose pretreated under the optimal condition was analyzed by XRD and FT-IR to evaluate their impacts on the crystal structure, functional groups and hydrogen bonds. The results showed that NaOH/H2O2/H2O, ethylene glycol(EG)/H2O2/H2O, CH3COCH3/NaOH and EtOH/NaOH systems exhibited better performance on the cellulose than other chemical reagents systems. The crystallinities of the pretreated celluloses were decreased from 65.3% to 61.3%, 63.7% and 49.8% as treated by NaOH/H2O2/H2O, EG/H2O2/H2O and EtOH/NaOH systems, respectively. The percentages of intermolecular hydrogen bonds were declined to 58.7%, 58.2% and 50.3% from 61.5%, respectively, but no crystal form changes were observed. However, in contrast, the crystal type changed as the cellulose was treated by CH3COCH3/NaOH system, and its crystallinity and percentage of intermolecular hydrogen bonds were reduced by 18 percent point and 14.7 percent point, respectively. References | Related Articles | Metrics

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Liquefaction of Fir Sawdust Catalyzed by [Psmim] HSO4 and Characterization of Liquefaction Products ZHENG Huai-yu, LU Ze-xiang, FAN Li-wei, HUANG Biao, LIAO Yi-qiang, HU Yang 2014, 34 (2):  91-96.  doi: 10.3969/j.issn.0253-2417.2014.02.016 Abstract ( 728 )   PDF (1639KB) ( 923 )   Save 1-(4-sulfopropyl)-3-methylimidazolium hydrosulfate ([Psmim] HSO4) was synthesized and its structure was characterized by FT-IR and 13C NMR. The catalytic performance of [Psmim] HSO4 in liquefaction of fir sawdust was preliminarily investigated using 1-octanol as solvent. The liquefaction products were characterized by FT-IR, XRD, TG, GC-MS. The structure of the synthesized ionic liquid was confirmed by the analysis of FT-IR and 13C NMR characterization. The liquefaction experimental results showed that the ionic liquid exhibited a good catalytic performance for the liquefaction of sawdust.The conversion of 66.5% was achieved when 8.6 mmol of catalyst was used with application of 10 g fir sawdust and 60 g 1-octanol at the temperature of 150 ℃ for 60 min. The surface of the solid residue was covered with lignin derivatives. The light oil mainly contained the liquefied products originated from cellulose and hemicellulose, and the heavy oil consisted mainly of the degradation products from lignin. References | Related Articles | Metrics

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Cellulose Enzymatic-assisted Extraction of Proanthocyanidins from the Larch Bark after Degreasing by Supercritical CO2 JIANG Gui-quan, FANG Gui-zhen, SHI Zhen-xin, ZHANG Zhuo-rui, PANG Jiu-yin 2014, 34 (2):  97-102.  doi: 10.3969/j.issn.0253-2417.2014.02.017 Abstract ( 848 )   PDF (2227KB) ( 678 )   Save The supercritical fluid extraction combined with enzymatic hydrolysis technology for extracting proanthocyanidins from the larch bark was studied. Firstly, lipophilic components from the larch bark were extracted by supercritical CO2 at 50 ℃ for 130 min (extraction pressure was 35 MPa), and the average extraction yield of grease was 2.16%. Then proanthocyanidins were extracted from the raffinate with cellulase-assisted. The optimum extraction condition, through the single factor and orthogonal test to determine were as follows:3 g degreased bark powder, Buffer solution as the solvent, the material for the granularity of the raw material 150-178 μm, 0.6% of raw material quality as the amount of the fiber enzyme addition, the liquid-solid ratio 14:1(mL:g), the pH of enzymatic hydrolysis 5, the enzymolysis temperature 40 ℃. After enzymolysis 2 h, the yield of proanthocyanidins can reach 7.36%. The analysis showed that the fiber structure of bark had been damaged with different degrees after the extraction with cellulase-assisted methods by SEM and FT-IR. And hence this facilitated mass transfer and promoted extraction efficiency. The structure unit of procyanidins type is confirmed mainly in the proanthocyanidins molecule of the larch bark. The structure of efficient component was not changed. References | Related Articles | Metrics

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Synthetic of 6-(4-Methylpent-3-enyl)naphthalene-1,4-dione FENG Hong-jun, YANG Jiu-fang, GAO Fei-fei, LUO Jin-yue, LU Qiang, XU Xu 2014, 34 (2):  103-107.  doi: 10.3969/j.issn.0253-2417.2014.02.018 Abstract ( 671 )   PDF (1282KB) ( 622 )   Save The myrcene and 1,4-benzoquinone are used as raw materials to synthesize naphthalene catechol derivatives of naphthalene-1,4-diol. Further the naphthalene catechol derivatives of naphthalene-1,4-dione is synthesized by aromatization. The structure of the product is identified as 6-(4-methylpent-3-enyl)naphthalene-1,4-dione by GC-MS, the FT-IR, 1H NMR characterization. The synthesis conditions from hydronaphthoquinone to morkit were investigated. The experimental parameters such as different type of catalysts, catalyst amount, reaction solvent, reaction temperature and reaction time have been investigated systematically with single-factor experimentation to obtain maximum yield. It is concluded that the fittest catalyst is manganese(IV) oxide, while the dosage of naphthalene-1,4-diol and catalyst is 0.02 mol and 0.05 mol, respectively. Acetic ester is chosen as solvent and the reaction temperature is 80 ℃, reaction time is 22 h. Under this condition, the yield of product reached 88.6%. Manganese(IV) oxide catalyst can be reused four times, while the yield decline is not obvious. References | Related Articles | Metrics

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Preparation and Characterization of Oxidized Starch with High Contents of Carboxyl Groups DING Long-long, ZHANG Yan-hua, GU Ji-you, TAN Hai-yan, ZHU Li-bin 2014, 34 (2):  108-112.  doi: 10.3969/j.issn.0253-2417.2014.02.019 Abstract ( 817 )   PDF (1756KB) ( 625 )   Save An oxidized starch with the contents carboxyl groups (CCG) of 2.55% was prepared through a highly efficient oxidation method. The different oxidized parameters associated with CCG of the oxidized starch was then investigated systematically. The results indicated that the highest CCG of 2.55% can be obtained under the condition described as gelatinization temperature of 80 ℃, 1.716% FeSO4(catalyst), 40% H2O2(oxidant), reaction temperature of 55 ℃ and reaction time of 1.5 h. The structures and properties of oxidized starches were characterized by FT-IR, XRD and DSC. It was found that the oxidized starch with high CCG was a polymer with amorphous phase, and different CCG gave rise to different degree of crystallization. The early gelatinization, as well as the initial oxidation of starch, took place first in the amorphous lamellae of starch. With the increase of the extent of the oxidation, the oxidation shifted to crystalline region. References | Related Articles | Metrics

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The Adsorption Performance of Activated Carbon for Nitro Phenol Isomers LU Yong-yu, WANG Xiao-yan, ZHOU Jian-bin, PAN Rui, LIU Bin, MA Ye 2014, 34 (2):  113-118.  doi: 10.3969/j.issn.0253-2417.2014.02.020 Abstract ( 585 )   PDF (1679KB) ( 659 )   Save Adsorption performance of activated carbon for nitro phenol isomers was investigated.The results showed that the highest adsorption capacity of o-nitrophenol,m-nitrophenol, p-nitrophenol on activated carbon are 676.03, 475.17 and 449.56 mg/g under the temperature of 25 ℃ and neutral conditions, respectively. The adsorption behavior of o-nitrophenol on activated carbon is different from the other two isomers. With the increasing of temperature, adsorption of o-nitrophenol in activated carbon was also increased. Under the acidic conditions, the adsorption amount of nitro phenol isomers was in the order of o-nitrophenol>p-nitrophenol>m-nitrophenol. Adsorption of m-nitrophenol can be improved in activated carbon by increasing the pH value. The adsorption isotherms of nitro phenol strictly accord with Langmuir equation, which is a single molecule layer absorption. References | Related Articles | Metrics

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Fungicidal Effect of Isolates on Aspergillus flavus by Fumigation WU Ke-gang, LIN Ya-hui, DUAN Xue-juan, CHAI Xiang-hua, ZHAO Xin-xin 2014, 34 (2):  119-125.  doi: 10.3969/j.issn.0253-2417.2014.02.021 Abstract ( 649 )   PDF (1800KB) ( 671 )   Save The fungicidal effects of seven natural isolates were evaluated by flat plate fumigation and block transfer methods. Results showed the fungicidal activity of isolates was in the order of cinnamaldehyde>thymol, salicylaldehyde, citral>anethole>eugenol. However, vanillin did not showed any fungicidal activity. The compound of salicylaldehyde, thymol, citral and cinnamaldehyde, in a ratio of 5:5:5:1, showed significant synergy effect, with the minimum fungicidal concentration (MFC) of 0.031 25 mL/L. SEM analysis showed that the isolate compound made the hypha of Aspergillus flavus become thinner, breakable and wizened, and the spores become shrunken and deformed. The compound affected the normal growth and metabolism of A. flavus, and led to fungistatic or fungicidal activity. The high electron density positions of isolate molecules were the active sites of fungicidal activity. More active sites with higher electron density and smaller steric hindrance resulted in the stronger fungicidal activity. The findings of the present study demonstrated the possible exploration of plants based isolates as safety preservatives against fungal spoilage during food stuffs storage. References | Related Articles | Metrics

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Research Progress of Cellulose Self-assembly Nanoparticles WU Wei-bing, ZHUANG Zhi-liang, JING Yi, DAI Hong-qi 2014, 34 (2):  126-133.  doi: 10.3969/j.issn.0253-2417.2014.02.022 Abstract ( 829 )   PDF (5240KB) ( 1008 )   Save The backbone, hydrophobic side chain, and responsive type of the amphiphilic cellulose copolymers that form cellulose self-assembly nanoparticles (CSANPs) were summarized. The particle size, morphology and structure of CSANPs under different conditions were introduced, too. Owing to the intelligent responses, CSANPs have important applications in the areas of intelligent materials and biomedicine, especially in drug carrier and controlled release. Biodegradable CSANPs with controllable morphology and intelligent responses (light, magnetism, pH, temperature, biology, etc.) are becoming the research hotspot in the field of cellulose materials. References | Related Articles | Metrics