Table of Content

30 December 2006, Volume 26 Issue 04 Previous Issue    Next Issue

研究报告

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Preparation and Anticoagulation Activity of β-1,4-Glucan Sulfate WANG Zhao-mei;LI Lin;GUO Si-yuan;XIAO Kai-jun 2006, 26 (04):  1-5.  Abstract ( 575 )   PDF (1019KB) ( 629 )   Save Various β-1,4-glucan sulfates(GS) were synthesized by sulfate of microcrystalline cellulose. Their sulfate substitute degree (Ds) varied in the range of 1.10 to 1.70. GS with Ds of 1.70 was selected for structural analysis and anticoagulation investigation. IR spectra showed the introduction of sulfate groups by sulfation. 13CNMR indicated that sulfation occurred mainly at C6, partially at C2 and no sulfate substitution occurred at C3. Coagulation assays showed that 0.2 mg/L GS could significantly prolong tAPTT and tTT in plasma. The dosage of GS required to double tAPTT of normal human plasma was 0.7 mg/L, lower than that of heparin with the anticoagulation activity of 150 IU/mg. Its potent of anticoagulation in vitro reached the efficacy of heparin in definite range of concentration. Chromogenic analysis revealed that the anticoagulation mechanism of GS was mainly due to the inhibition of the coagulation factors Ⅱa & Xa activities mediated by antithrombin AT-Ⅲ. Related Articles | Metrics

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Quantitative 13CNMR Analysis of Urea-formaldehyde Resin for E1-type Plywood JIN Li-wei;WANG Chun-peng;ZHOU Dao-bing;CHU Fu-xiang;ZHAO Lin-wu 2006, 26 (04):  6-10.  Abstract ( 679 )   PDF (793KB) ( 548 )   Save The urea-formaldehyde (UF) resins for E1-type plywood synthesized by specific procedure were quantitatively examined by the 13CNMR spectroscopy. It was proved that 70.27% of formaldehyde molecules were transformed into hydroxy-methylurea and 24.83% formaldehyde molecules were transformed into methylene-ether bond during the initial alkaline reaction stage(pH value 7.2-7.8). About 64% of hydroxymethyl groups formed in the initial alkaline reaction stage were polymerized during the subsequent acidic reaction stage(pH value 5.4-5.6)by forming methylene or methylene-ether bonds and releasing some formaldehyde. The free formaldehyde of resin could react with the second dosage of urea during the next acidic reaction stage(pH value 6.5-6.9) to form hydroxymethylureas. More than half of methylene-ether bonds were decomposed during the last alkaline cooling stage(pH value 7.5-8.0)and reacted with the third dosage of urea to form hydroxymethylurea. Related Articles | Metrics

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Research on Reaction Kinetics of Disproportionation of Gum Rosin Catalyzed by AH Non-noble Metal Catalyst WANG Ya-ming;WANG Lu-hui;JIANG Li-hong;WANG Zhen 2006, 26 (04):  11-14.  Abstract ( 694 )   PDF (1188KB) ( 619 )   Save The reaction of disproportionation of gum rosin catalyzed by AH non-noble metal catalyst was studied, and the effects of reaction temperature, reaction time, particle size of catalyst, and stir speed were investigated. It was found that the reaction was of the first order at 240-270℃. Reaction rate constants were 2.9×10-3, 3.1×10-3, 1.42×10-2, 2.51×10-2min-1 at 240, 250, 260 and 270℃,respectively. Apparent activation energy E was 184.80×103 kJ/mol, frequency factor A was 1.453×1016. Related Articles | Metrics

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Study on Determination of Polyphenol Content in Canarium album (Lour.) Rauesch. by Folin-Ciocalteu Colorimetry HE Zhi-yong;XIA Wen-shui 2006, 26 (04):  15-18.  Abstract ( 797 )   PDF (673KB) ( 1339 )   Save A quantitative determination method of polyphenol from Canarium album (Lour.) Rauesch. was studied by Folin-Ciocalteu colorimetry. The results showed that polyphenol content of C. album could be well calculated according to their colorime-tric absorption at 765 nm by applying Folin-Ciocalteu reagent 1.5 mL and 10% Na2CO3 6 mL, 2 h at 30℃ for colorimetric reaction, and the linear range of standard curve was 7-70 mg/L. The method established was very convenient, stable and accurate. Related Articles | Metrics

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Antitumor Triterpenoids from Tripterygium wilfordii Hook. F. YANG Guang-zhong;LI Yuan-chao 2006, 26 (04):  19-22.  Abstract ( 927 )   PDF (581KB) ( 712 )   Save To study the active principles of Tripterygium wilfordii Hook. f., nine triterpenoids were isolated from this plant by column chromatography with silica gel. Their structures were identified as triptotin D(1), triptotin E(2), orthosphenic acid (3), triptotin H(4), 22-β-hydroxy-3-oxo-Δ12-oleanen-29-oic acid (5),triptotriterpenic acid C(6), triptotin G(7), wilforic acid A(8) and wilforol A(9). Compounds 7 and 9 showed strong inhibition against P-388 rat leukaemia cell line. Compound 1 showed strong inhibition against A-549 adenocarcinoma cell of lung. Related Articles | Metrics

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Triterpenoids from the Aerial Parts of Lonicera syringantha Maxim. QIAN Zheng-ming;LI Hui-jun;LI Ping;HE Qing-hui;QI Fang-fang 2006, 26 (04):  23-25.  Abstract ( 593 )   PDF (390KB) ( 644 )   Save Triterpenoids from the aerial parts of Lonicera syringantha Maxim. were studied. Five triterpenoids were isolated and their structures were identified to be cauloside C (1),akebiasaponin D (2),akebiasaponin F (3),ursolic acid (4) and hederagenin (5). Compound 4 was isolated from the genus Lonicera for the first time and all 5 compounds were first isolated from the species of this plant. Related Articles | Metrics

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Preparation and Application of Copper-loaded Activated Carbon Catalyst for Catalytic Oxidation of Dye Wastewater LI Wei-feng;ZHU She-min;SONG Tian-shun;CHEN Yang;CHEN Ying-wen;SHEN Shu-bao 2006, 26 (04):  26-30.  Abstract ( 698 )   PDF (1061KB) ( 841 )   Save The catalyst, which is composed of activated carbon as carrier and loaded with copper oxide (CuO) as active component,was made and main factors in the preparation of this catalyst were further analyzed. Under the optimized preparation condition of nitric acid 2.5 mol/L,soaking time 12 h, concentration of Cu(NO3)2 7.5%, calcination temperature 280℃ for 3 h, the optimum catalytic activity could be obtained. The best catalytic oxidation process of dye wastewater treatment was also investigated by this catalyst. The regeneration process of deactivated catalyst was also investigated and the activity of regenerated catalyst was recovered to about 90%. Related Articles | Metrics

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Thermal Stability of Bismaleimide-epoxy Resin Modified by Tung Oil-maleic Anhydride Adduct SHANG Shi-bin;WANG Dan;GAO Hong;WANG Ding-xuan 2006, 26 (04):  31-33.  Abstract ( 736 )   PDF (565KB) ( 797 )   Save A cured epoxy resin with high thermal stability was prepared from tung oil, a bismaleimide, maleic anhydride and an epoxy resin (E-51). The effect of dosages of each component and the curing conditions were investigated. The optimum condition is as follows:weight ratio of tung oil/bismaleimide/maleic anhydride/E-51 is 1:0.25:0.2:0.4, curing temperature is 150℃ and curing time 5 h,the temperature index (T20000) of the resin is 160.8℃. Related Articles | Metrics

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Study on the Synthesis of Disproportionated Rosin (2-Hydroxyethyl Acrylate) Ester LIN Ming-tao;CHU Fu-xiang;MA Li;ZHOU Dao-bing;WANG Ji-fu;WANG Chun-peng 2006, 26 (04):  43-47.  Abstract ( 687 )   PDF (921KB) ( 804 )   Save Disproportionated rosin (DPR) (2-hydroxyethyl acrylate) ester was synthesized by acyl chlorination and esterification of DPR acid. The influences of temperature, reaction time and molar ratio of the reaction were studied by monitoring the course of reaction. The optimum conditions of acyl chlorination and esterification were investigated as follows:molar ratio of DPR to PCl3 1:0.33, reaction temperature 50℃ and reaction time 3 h. It was found that temperature had no significant effect on acylation of DPR, and the increase of molar ratio of PCl3 had a positive impact on the reaction degree. The results also showed that IR, 13CNMR and GC-MS were effective methods for tracking the course of acylation and esterification reaction. Related Articles | Metrics

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Study on Elemental Chlorine-free Bleaching Properties of Kraft Pulp of Acacia Wood Species DENG Yong-jun;FANG Gui-gan;LI Ping;LIU Jun-liang;JIANG Ze-hui 2006, 26 (04):  34-38.  Abstract ( 690 )   PDF (978KB) ( 581 )   Save Pulping and bleaching performances of 4 wood species(Acacia auriculiformis Willd.,A. mangium Willd., A. crassicarpa and A.aulacocarpa)were studied and the properties of these pulps were compared. The results showed that the screened yields of these kraft pulps were from 46.95% to 50.95%.By using elemental chlorine-free(ECF)bleaching, all these bleached pulps had high ISO brightness and high physical properties,the brightness of these pulps could be bleached from 86.0% to 89.2%, ISO;on 30°SR beating degree, the tensile indexes of these bleached pulps could reach from 55.8 to 60.7 N·m/g.The comprehensive kraft pulping potentials of these wood species were summarized that A.uriculiformis is the best one, A. mangium and A.aulacocarpa are in the middle,and A. crassicarpa is the worst. Related Articles | Metrics

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Study on Preparing Isolongifolene from Longifolene Catalyzed by Solid Superacid LUO Jin-yue;AN Xin-nan;LEI Fu-hou 2006, 26 (04):  39-42.  Abstract ( 746 )   PDF (787KB) ( 506 )   Save The reactions of isomerization of longifolene catalyzed by SO42-/TiO2-ZrO2 solid superacid are performed. From analyses of GC and GC-MS, the main product is isolongifolene from isomerization. The result shows that this catalyst has a high catalytic activity and a good selectivity to isomerization of longifolene. The factors affecting its catalytic activity are investigated. The result also shows that the optimum conditions for the preparation of SO42-/TiO2-ZrO2 catalysts are as follows:n(Ti):n(Zr) 3:1, and calcination temperature 550℃. Under these conditions, the optimum conditions for isomerization of longifolene are as follows:reaction time 4 h, isomerization temperature 165℃, and ratio of solid superacid to longifolene mass part 4%. Under these conditions, the conversion of longifolene is 99.1%, and the yield of isolongifolene is 97.2%. Furthermore, experiments on the effect of storage time of the catalysts on the reaction and the regeneration of catalysts are carried out. Related Articles | Metrics

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Study on Catalytic Hydrogenation of Terpinene Maleic Anhydride KONG Zhen-wu;WANG Hao;DU Yu-min;CHU Fu-xiang 2006, 26 (04):  48-50.  Abstract ( 620 )   PDF (597KB) ( 778 )   Save Hydrogenated terpinene maleic anhydride was prepared by catalytic hydrogenation of terpinene maleic anhydride in the presence of Pd/C catalyst. The affecting factors of hydrogenation, such as temperature, pressure and dosage of catalyst, were investigated.Hydrogenated terpinene maleic anhydride could be obtained in a short time with high reaction selectivity and conversion ratio by hydrogenation of terpinene maleic anhydride at reaction temperature from 150 to 160℃, pressure from 8 to 10 MPa and the dosage of catalyst from 4% to 6%. Related Articles | Metrics

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Preparation of Cardanol Formaldehyde Resin Emulsions LIU Yue-rong 2006, 26 (04):  51-53.  Abstract ( 733 )   PDF (584KB) ( 772 )   Save The cardanol formaldehyde resin(CFR) emulsions with high stability were prepared with the mixture of α-olefin sulfonate (AOS) and styrene-acrylamide-acrylic ester copolymer (BAA) at mass ratio 3:5 of AOS and BAA. The optimum emulsifying conditions were as follows:dosage of surfactants 10%, temperature 105-115℃, stirring rate 800 r/min. AOS and BAA showed the largest synergitic effect at mass ratio 3:5. When YGE-8 was added at dosage of 0.1% during formation of paper sheets, the dry and wet strengths of the sheets were increased by 17.1% and 16.3%,respectively. Related Articles | Metrics

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Viscosity Behavior and Spectral Characteristics of Nanocrystalline Cellulose GUO Rui;DING En-yong 2006, 26 (04):  54-56.  Abstract ( 618 )   PDF (590KB) ( 889 )   Save Nanocrystalline cellulose(NCC) has the backbone of cellulose, composed of β-(1→4)-D-glucopyranose units, also has many characteristics of nano-size particles which can be used in many fields. The morphological and behavior characteristics of NCC were analyzed by TEM,X-ray diffraction and FT-IR. The effects of NCC mass fraction, temperature, shearing rate, pH value and mass fraction of salt on the viscosity of colloidal NCC have been studied. Related Articles | Metrics

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Investigation on Oleoresin Resource of 3-Carene in Yunnan Province GENG Shu-xiang;YIN Xiao-bing;ZHENG Wan;WU Li 2006, 26 (04):  57-60.  Abstract ( 724 )   PDF (703KB) ( 717 )   Save Study on the chemical characteristics of oleoresins from Pinus kesiya var. langbianensis in Dehong of Yunnan was carried out by gas chromatography and mass spectrometry. Contents of 3-carene in oleoresin are as high as 8.52%-20.11%,averaging 19.50%. The content of 3-carene in oleoresin from one pine is as high as 25.33%,or 10.33% higher than that from P.densata oleoresin;The contents of 3-carene in turpentine are over 11%;The contents of 3-carene in oleoresin from Luxi and Lianghe of Yunnan are 8.52% and 20.11% respectively and 3-carene contents in turpentine are 19.47% and 34.88% respectively. The maximum 3-carene contents in oleoresin and turpentine are 27.50% and 44.99% respectively from one tree. However, 3-carene contents are low in oleoresins of P. kesiya var. langbianensis and P. yunnanensis Franch.The resource of oleoresin from P. kesiya var. langbianensis has been exploited on a large scale.Attentions should be paid to the exploitation of P. kesiya var. langbianensis. Related Articles | Metrics

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Study on Pyrolysis Characteristics of Macadamia Shell during Preparation of Activated Carbon NING Ping;YANG Yue-hong;PENG Jin-hui;ZHANG Shi-min;ZHANG Li-bo;CHEN Yu-bao 2006, 26 (04):  61-64.  Abstract ( 683 )   PDF (873KB) ( 697 )   Save Pyrolysis of macadamia (Macadamia ternifolia F.Muell.)shell with phosphoric acid as activating agent to prepare activated carbon was carried out by simultaneous measurements of thermogravimetry(TG) and differential thermal analysis(DTA),so as to study the pyrolysis mechanism of macadamia shell, the enthalpy change and weight loss. According to experimental data, all thermal analysis curves of macadamia shell have two weight loss-stages with related heat-absorption peak or heat-releasing peak under different conditions. Temperature interval of pyrolysis is from 200-410℃,residue amount is close to zero at 800℃. Soaked in phosphoric acid for 12 and 24 h, respectively, temperature range of charring and activating of phosphoric acid-macadamia shell is from 130-410℃ and amounts of residue are 34.431% and 17.743% respectively.The optimum activating temperature is about 400℃,soaking time is 24 h by phosphorylation. With increasing of soaking time, peak of DTG curve is gradually shifted to lower temperature,descending from 363.63℃ of the unsoaked to 243.71℃ and 238.37℃ of the soaked.Soaking of phosphoric acid enhances charring reaction and phosphoric acid-macadamia shell starts its pyrolysis at 130℃. The results provide significant theoretical basis in preparation of activated carbon of macadamia shell. Related Articles | Metrics

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Bio-membrane Treatment Technology for Straw Soda-AQ Pulp Effluent Containing Middle-stage Water from Hypochlorine Bleaching HU Jia;SHI Ying-qiao;DING Lai-bao;FANG Gui-gan;SIGOILLOT Jean-claude 2006, 26 (04):  65-69.  Abstract ( 610 )   PDF (1009KB) ( 646 )   Save The study on treatment of waste water of straw alkali pulp by white rot fungi has been made systemically in laboratory, the optimization conditions of white rot fungi culture have been given, and the relevant pilot-scale equipment of white-rot fungi treatment has been setup first in China. A reactor was used, using stainless steel wire as carrier for bio-film of white-rot fungi. The result of pilot-scale experiment showed that the removal rate of COD of straw pulping waste water is 73%-92.2%,the removal rate of BOD is 90.5%-97. 8%, when hydraulic reserved time (HRT) is 24 h.The quality of discharged water, by only white-rot fungi bio-treatment was:COD≤450 mg/L,BOD≤100 mg/L,SS≤100 mg/L,pH value 6-9, which meet the requirement of the national standard (GB 3544-2001). Related Articles | Metrics

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Study on Extraction Technology of Alkaloids from Thermopsis lanceolate by Supercritical Carbon Dioxide CAI Zhi-hui;NI Chuan-gen;JIA Rui-qin;SHEN Min-liang;WANG Hai-yun 2006, 26 (04):  70-72.  Abstract ( 631 )   PDF (514KB) ( 570 )   Save The needles of Thermopsis lanceolate R.Br. were extracted with supercritical carbon dioxide to obtain alkaloids. Factors affecting extraction yield were discussed. By orthogonal experiments, the optimum technological conditions were:extraction temperature 45℃, pressure 20 MPa, flow rate of carbon dioxide 20 kg/h and extraction time 80 min. The yield of alkaloids was 3.12%. Related Articles | Metrics

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Studies on Solid Superacid SO42-/TiO2 Modified by Rare Earth Element and Its Catalysis for Synthesis of Terpinyl Acetate ZHAO Qian-rong;WU Chun-hua;BI Yun-mei;ZHANG Tao;GONG Ye;TONG Yan-xiu 2006, 26 (04):  73-77.  Abstract ( 611 )   PDF (1179KB) ( 622 )   Save Common solid superacid SO42-/TiO2 was modified by several rare earth elements. The results showed that Ce4+ was the best modifying agent among these rare earth substances. Ce4+-modified solid surperacid SO42-/TiO2-Ce4+ displayed excellent activity when superacid SO42-/TiO2 was impregnated by 7.5% Ce4+ and then calcined at 500℃ for 3 h. The structure of SO42-/TiO2-Ce4+ was characterized by TEM, XRD and IR methods. The catalyst was a nanomaterial with uniform granularity of 32 nm. Synthesis of terpinyl acetate from terpineol and acetic anhydride with solid superacid SO42-/TiO2-Ce4+ as catalyst had been studied for the first time. By orthogonal test, the optimum condition was obtained as follows:reaction temperature 70℃, reaction time 6 h, catalyst dosage 3%, ratio of terpineol to acetic anhydride 1:1.5. Under this condition, the conversion of terpineol was over 99%, and the content of terpinyl acetate in the product was 90%. Compared with common superacid SO42-/TiO2, the modified SO42-/TiO2-Ce4+ had higher catalytic activity and selectivity. Related Articles | Metrics

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Study on Modification of Immobilized Cells for Fermenting Xylitol LIN Hai;WANG Shen-jian;LUO Hui;MIAO Wen-ping 2006, 26 (04):  78-82.  Abstract ( 564 )   PDF (887KB) ( 531 )   Save Three different methods, namely, addition, displacement and mixing were adopted so as to improve the strength of calcium-alginate beads. The effects of proportions of modifiers, concentration of displacing substance, calcification time and displacing time on the beads were inspected and the strength of immobilized cells reached the maximal value after the mixture of sodium alginate solution and cells was added with mass fraction 1.0% of MgO and calcified for 4 h. The immobilized cells can be used for the fermentation of xylitol lasting 36 days i.e. 12 batches and on average, the final mass concentration of xylitol is 43.2 g/L and the yield of xylitol is 53.8%. Related Articles | Metrics

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Study on Extraction of Curcumin by Different Methods LI Xiang-zhou;ZHANG Yan-qiang;LIU Yan-hua;SUN Chong-lu 2006, 26 (04):  83-86.  Abstract ( 657 )   PDF (610KB) ( 730 )   Save By orthogonal experiment, extraction of curcumin from rhizome of Curcuma longa Linn. with metheds of conventional solvent, ultrasonic and microwave assisted extraction were studied. Under optimum extraction conditions, the yields of curcumin by these methods were 2.53%, 3.22%, 3.61% with one-time extraction respectively, and the extraction yields were 62.6%, 79.7%, 89.3% respectively. Microwave assisted extraction has a bright prospect in the curcumin extraction with the characteristics of considerable time saving and high extraction efficiency. Related Articles | Metrics

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Studies on Chemical Constituents and Antimicrobial Activities of Persimmon Leaves JI Zhi-ping;SU Yin-quan;LV Ping-hui;Zhang Cun-li 2006, 26 (04):  87-91,9.  Abstract ( 678 )   PDF (463KB) ( 686 )   Save Chemical constituents of persimmon leaves and antimicrobial activities were studied. Results showed that persimmon leaves contained alkaloids, saponins, amino acids, polypeptides, organic acids, phenolic compounds and tannins, saccharides, steroids, flavones, cardiac glycosides, anthraquinones, naphtha, etc. Results of experiments on antibacterial and antifungal activities showed that extracts of alcohol and acetic ester had remarkable bacteriostasis effects against 6 bacteria;aqueous extract was more effective against fungi, and slight against bacteria;petroleum ether extract had no effect against bacteria and fungi;butylalcohol extract had different effects against bacteria, but had no effects against fungi. Results of bacteriostasis activities of acetic ester extract under different concentrations showed that the higher concentration, the stronger bacteriostasis effect was, and that the sequence of bacteriostasis activities was different under different concentrations. Related Articles | Metrics

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Study on Modified Urea-formaldehyde Resin for Rice-straw Medium Density Fiberboard LIAN Hai-lan;YOU Ji-xue;ZHOU Ding-guo 2006, 26 (04):  92-96.  Abstract ( 1007 )   PDF (917KB) ( 775 )   Save In order to prepare modified urea-formaldehyde (UF) resin suitable for manufacturing rice-straw medium density fiberboard (MDF), the differences among properties of modified UF resins were investigated,including the influences on the properties of rice-straw MDF bonded with UF resin modified with melamine, KH-550, dimethyl silicon oil and silicone resin respectively. The results showed that UF resin modified with melamine (MUF) was effective to bond rice-straw fiber boards, which could improve the properties of board and had an reasonable cost. Analyses by FT-IR, UF and MUF resins showed similar curve shapes. MUF resin was water-proof with more amino groups and fewer methylol. DSC results showed that MUF resin demanded higher curing temperature compared to UF resin. The surface tension of MUF resin was 6.3% less than that of UF resin, hence wetting ability of MUF to straw fiber was improved, which enhanced the diffuse and penetration of the resin into straw fibers and resulted in higher bond strength of the board. Related Articles | Metrics

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Studies on Synthesis and Surface-activity of Peptide-based Surfactants RAO Xiao-ping;SONG Zhan-qian;GAO Hong 2006, 26 (04):  97-99.  Abstract ( 575 )   PDF (590KB) ( 748 )   Save Three peptide-based surfactants including palmitylglycine(A),stearatylglycine(B) and dehydroabietylglycine(C) were synthesised from biomass resources of palmitic acid, stearatic acid and dehydroabietic acid respectively through the reaction of carboxyl-protecting with glycine. Their structures were characterized by IR spectroscopy. The surface-activities of them were also investigated. It has been found that the synthesised surfactants have good foaming power and emulsifying capacity. Palmityl-glycine is the best of them, the height of foam can reach 112 mm and water-oil separation time can reach 15 min. Peptide-based surfactants are environment-friendly. Related Articles | Metrics

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Researches on Isolation, Purification and Anti-complementary Activity of Acidic Polysaccharide from the Stems of Avicennia marina( Forsk. )Vierh. FANG Xu-bo;JIANG Bo;WANG Xiao-lan 2006, 26 (04):  100-104.  Abstract ( 736 )   PDF (1050KB) ( 602 )   Save Crude polysaccharides were isolated from the stems of Avicennia marina (Forsk.)Vierh. by hot water extraction and ethanol precipitation. The polysaccharides were further fractioned by ultra-filtration, deproteinated by trichloroacetic acid, deco-lorized by DEAE-cellulose and then isolated by anion-exchange chromatography of DEAE-Sepharose fast-flow and size-exclusion chromatography of Sephacryl S-400. The purified polysaccharide HAM-3-Ⅱb-Ⅱwas proved to be homogeneous by HPGFC and polarimetry. Its molecular weight (Mw) and specific rotation were 105 200 and +27.54° respectively. Analysis of monosaccharide composition indicated that HAM-3-Ⅱb-Ⅱ contained high proportions of galacturonic acid, arabinose, galactose and rhamnose, characterizing an acidic heteropolysaccharide. UV spectra of HAM-3-Ⅱb-Ⅱ showed absence of nucleic acid and protein. The characteristic absorptions of IR confirmed the presence of pectic polysaccharide. The measurement of activity was performed by complement fixing test, HAM-3-Ⅱb-Ⅱexpressed potent anti-complementary activity via classical and alternative pathways with the increase proportional to dosage. Related Articles | Metrics

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Study of Acid-catalyzed Steam Explosion Pretreatment for Enzymatic Hydrolysis of Wheat Straw LUO Peng;LIU Zhong;WANG Gao-sheng 2006, 26 (04):  105-109.  Abstract ( 677 )   PDF (760KB) ( 701 )   Save Steam explosions,of different intensities to pretreat wheat straw impregnated in sulfuric acid of 0.5% concentration were carried out. The effects of pretreatment intensity on total gravimetric recovery, hemicellulose-sugar recovery, yield of hemicellulose-derived sugars,recovery yield of cellulose, and yield of enzymatic hydrolysis of cellulose were analyzed. Defiberation of wheat straw raw material occurred during steam explosion pretreatment. Total gravimetric recovery decreased and screened gravimetric recovery increased as pretreatment intensity increased. Raising pretreatment intensity led to increase of cellulose and hemi cellulose degradation and enzymatic hydrolysis yield of cellulose. At the condition of pretreatment intensity of 4.14, the hydrolysis of hemicellulose reached the highest degree, the screened gravimetric recovery yield was 62.0%, the enzymatic hydrolysis yield was 73.4%. The optimum pretreatment intensity was 3.55, which resulted in the highest glucose recovery of 20.0% in the water insoluble fiber and the highest total sugars recovery of 13.0% in the filtrate. Related Articles | Metrics

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Study on Isolation and Identification of Triterpene Acid from Gardenia jasminodes Eills LIAO Xiao-feng;CHEN Zheng-xing;YU Rong 2006, 26 (04):  110-112.  Abstract ( 779 )   PDF (647KB) ( 497 )   Save Isolation and purification of triterpene acid from fruit of Gardenia Jasminodes Eills were studied,the optimum processing conditions are:the granularity of powder 0.4 mm, ratio of liquid to solid 8:1, temperature 85℃, 3 times of extraction of 2.5 h each, and concentration of alcohol 95%.Extraction rate of ursolic lixiviate is 92.6%. Structural identifications by DSC,IR,EI-MS,1H and 13CNMR,HPLC show that the triterpene acid is ursolic acid,the average content of ursolic acid is 0.444 5%。 Related Articles | Metrics

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Study on Technology of Extracting Aucubin from Eucommia Fruit by Supercritical Carbon Dioxyde ZHANG Yong-kang;HU Jiang-yu;LI Hui;OUYANG Hui;YIN Yong-zhong 2006, 26 (04):  113-116.  Abstract ( 575 )   PDF (829KB) ( 608 )   Save The technology of extracting aucubin from eucommia ( Eucommia ulmoides Oliv.) fruit was studied using technique of supercritical CO2 extraction with suitable cosolvent. The influence of extracting factors on extraction effect was studied using orthogonal test table L16(45). The aucubin content of extracted solutiom was determined by spectrophotometry using chromogenic reaction of Epstahl with aucubin. The study indicates that the technique of supercritical CO2 extraction is better than traditional technique in many respects such as simple operation, good conservation of active component and easy separation. The optimum extraction yield of aucubin is 1.921% at extracting pressure 26 MPa, extracting temperature 55℃, separation temperature 30℃, extracting time 120 min, and ratio of cosolvent (75% alcohol) with raw materials 6:1(mL:g). Related Articles | Metrics

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Progress of Research on Cellulose Hydrolysis in Supercritical Water WANG Li-ping;LV Hui-sheng;ZHANG Min-hua 2006, 26 (04):  117-120.  Abstract ( 627 )   PDF (632KB) ( 1093 )   Save Hydrolysis of microcrystalline cellulose in supercritical water was reviewed. The main reaction pathway, reaction mechanism and reaction kinetics were described on the basis of detailed product analyses. Compared with traditional technologies of acid hydrolysis and enzymatic saccharification, the technology of supercritical hydrolysis has the advantages of high efficiency, simple processing and environment friendly. The application prospect of this technology is described. Related Articles | Metrics

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Study on Extracting Volatile Components from Oregano by Supercritical CO2 CHE Guo-yong;PANG Hao;LIAO Bing;ZHANG Jing-cheng 2006, 26 (04):  121-123.  Abstract ( 677 )   PDF (558KB) ( 679 )   Save Volatile extract was obtained from oregano (Origanum vulgare L.) by supercritical CO2 extraction with cosolvent. The chemical composition of the extract of oregano was studied by GC-MS technique, 20 compounds were identified. The extract was compared with the essential oil gained by hydrostillation. The results showed that the content of oregano essential oil by supercritical CO2 extraction with cosolvent was obviously higher than that by hydrostillation. The greater the polarity of cosolvent is, the higher is the content of antioxidant. Related Articles | Metrics

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Structural Identification of the Oxidation Products of Nopyl Ethyl Ether by GC-MS CHEN Jin-zhu;XIAO Zhuan-quan;WANG Zong-de 2006, 26 (04):  124-127.  Abstract ( 492 )   PDF (722KB) ( 490 )   Save Nopyl ethyl ether was oxidized in alkaline potassium permanganate solution, and the structures of 8 main products were identified by GC-MS, which are 2,2-dimethyl-3-(β-ethoxypropionyl)cyclobutanone, cis-2,2-dimethyl-3-(β-ethoxypropionyl) cyclobutaneacetic acid, 3-hydroxy-cis-2,2-dimethyl-3-(β-ethoxypropionyl) cyclobutan-eacetic acid, 2,3-dihydroxynopyl ethyl ether,1-hydroxy-cis-2,2-dimethyl-3-(β-ethoxypropionyl) cyclobutaneacetic acid and 5-hydroxy-2,3-epoxynoyl ethyl ether. Related Articles | Metrics