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Table of Content

    30 March 2005, Volume 25 Issue 1 Previous Issue    Next Issue
    研究报告
    ANALYSIS OF POLYGENETIC AFFINITIES AMONG YEAST STRAINS WITH RANDOM AMPLIFIED POLYMORPHISM DNA ANALYSIS
    XU Yong;ZHANG Bo;YONG Qiang;HUANG Min-ren;YU Shi-yuan
    2005, 25 (1):  1-4. 
    Abstract ( 569 )   PDF (556KB) ( 646 )   Save
    The genotypic polymorphism and polygenetic affinities of intergenus, interspecies and intraspecies among 21 strains from 6 yeast genus were studied with random amplified polymorphism DNA(RAPD) analysis.The results showed that the mini-differences of intraspecies in genetics could be distinguished and particular electrophoretic bands were selected as characteristic markers in the classification and identification of yeast with RAPD.The genetic distance between Candida shehatae and C.tropicalis was 0.114,and the genetic distance between them and Pichia stipitis reached 0.493.The genetic distance between Schizosaccharomyces pombe and Bettanomyces custersii was 0.322,the genetic distance between Pachysolen tanophilus and C. krusei was 0.383 and the genetic distance between them and Saccharomyces cerevisiae reached 0.443.The genotypic classification of species except Candida seemed to be consis-tent with traditional morphological classification.
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    STUDIES ON INDIRECT ELECTROLYTIC OXIDATIONS OF p-CYMENE AND ITS CRACKING PRODUCT——TOLUENE
    BI Liang-wu;LIU Xian-zhang;ZHAO Zhen-dong;XU Peng-xiang;CHU Fu-xiang
    2005, 25 (1):  5-9. 
    Abstract ( 638 )   PDF (960KB) ( 708 )   Save
    Reasonable condition for electrolytic oxidation of Mn2+ to Mn3+ in a diaphragmless electrolytic cell using anodic and cathodic electrodes of Pb-Sb alloy are:5:1 area ratio of anode to cathode,5 mol/L of sulfuric acid,80 (mA/cm2) of anodic current density,1 mol/L of Mn2+,25-35℃ of temperature,1.20 of Coulomb ratio.Current (efficiency) is about 60%,and electrolytic yield is over 70% under the above condition.When the ratio of Mn3+ to (p-cymene) is about 4:1(molar ratio),selectivity of cuminaldehyde in the oxidized products is relatively high.Yields of main oxidized products,namely p-methyl acetophenone and cuminaldehyde are 55.19% and 31.64%,respectively.Suitable condition for oxidation of toluene by Mn3+ is that the ratio of Mn3+ to toluene is about 1:6(molar ratio).Yield of benzaldehyde is 73.67%.The electrolytic liquor can be repeatedly used over 8 times by regeneration after (extraction) by n-hexane and adsorption by activated carbon.
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    ADSORPTION OF METAL IONS BY MYRTAN TANNINS IMMOBILIZED ON COLLAGEN FIBER
    WANG Ru;LIAO Xue-pin;HOU Xu;SHI Bi
    2005, 25 (1):  10-14. 
    Abstract ( 761 )   PDF (770KB) ( 1093 )   Save
    Using collagen fiber as matrix,the immobilized myrtan tannins (IMT) was prepared through aldehyde cross-linking reaction.As a novel adsorbent,its abilities of recovering Pb2+,Cd2+and Hg2+ from waste water were studied.(Experiments) showed that the sequence of adsorption capacities of the metal ion on the adsorbent were Hg2+ >Pb2+ >Cd2+.The adsorption capacity was related to pH value of solution.The highest adsorption capacity of Hg2+(occurred) at pH value 7.0,whilst those of Pb2+ and Cd2+ occurred at pH value 3.0.Under the optimized pH value conditions,the equilibrium adsorption capacity of Hg2+ on the IMT was 198 mg/g and those of Pb2+ and Cd2+ were 87 and 24 mg/g respectively,when adsorption process was undertaken by using 0.1 g IMT and 100 mL metal ion solution with initial concentration 200 mg/L.The characteristic of adsorption kinetics and the influence of temperature on (adsorption) isotherms were investigated,both indicated that Hg2+ is mainly chemically adsorbed by the IMT,the (adsorption) of Pb2+ includes chemical and physical processes and that of Cd2+ is primarily due to physical association.These are related to the forms of metal ions in aqueous solution. It was also found that,when more than one metal ion existed in aqueous solution,the equilibrium adsorption capacity of each ion was not affected by others,implying that the IMT adsorbent is effective in simultaneous removal of these ions.
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    PREPARATIVE SEPARATION OF XYLOBIOSE AND XYLOTRIOSE AND THEIR IN VITRO APPLICATION IN FERMENTATION BY BIFIDOBACTERIA
    ZHANG Jun-hua;XU Yong;YONG Qiang;BU Xiao-li;YU Shi-yuan
    2005, 25 (1):  15-18. 
    Abstract ( 662 )   PDF (737KB) ( 835 )   Save
    Xylobiose and xylotriose were prepared from xylooligosaccharides by gel permeation chromatography,and their in vitro cultivation properties by Bifidobacterium adolescentis were investigated.Xylobiose and xylotriose were separated on polyacrylamide gel Bio-GelP-2 by FPLC system with degased high-purified water as eluant,and their (biological) characteristics toward bifidobacteria were studied.The results showed that the cell-dry-weights of B.adolescentis were 0.16,0.33 and 0.47 g/L,respectively,when xylose,xylobiose and xylotriose were used as carbon souces after 48 h cultivation in vitro.Xylotriose had superior effect than xylobiose and xylose on proliferation of B.adolescentis,and xylobiose had better effects than xylose.Xylobiose and xylotriose can reduce pH values of medium from 7.0 to 4.40 and 4.42,respectively.
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    STUDY ON RHEOLOGICAL PROPERTIES OF ALCOHOL-SOLUBLE LIGNIN SOL
    LIN Hai-yan;LUO Xue-gang
    2005, 25 (1):  19-22. 
    Abstract ( 595 )   PDF (728KB) ( 800 )   Save
    Rheological properties of alcohol-soluble lignin sol and the affecting factors,such as concentration,tem-(perature),pH value and plasticizers,etc.,were studied.The result indicated that the logarithm of viscosity of alcohol-(soluble) lignin sol was positively correlated with concentration and exhibited pseudoplastic characteristics.With the (increase) of temperature,sol viscosity decreased,following to Arrhenius equation.Around pH values 3.0 and 9.0,sol viscosity reached the highest.Around pH value 7.0,sol viscosity reached the lowest.Plasticizers increased sol (viscosity).Within the concentration range 0-0.25% of plasticizers,sol viscosity was positively correlated with the concentration of plasticizers.
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    CHROMATOGRAPHIC METHOD FOR DETERMINATION OF OXALIC ACID IN BLEACHING FILTRATES FROM THE PULP AND PAPER INDUSTRY
    HONG Feng;REIMANN Anders;JÖNSSON Leif-j;NILVEBRANT Nils-olof
    2005, 25 (1):  23-28. 
    Abstract ( 704 )   PDF (807KB) ( 612 )   Save
    Analysis and control of oxalic acid in bleaching filtrates has recently gained considerable attention in the pulp and paper industry due to problems with the formation of calcium oxalate scaling.Chromatographic methods,such as HPLC and ion chromatography(IC),are generally valuable as standard methods for determination of oxalic acid.In this study,a HPLC system equipped with an Aminex HPX-87H column was applied to determine oxalic acid in (authentic) bleaching filtrates.An established IC method based on separation with an anion-exchange column was used as reference method.The results showed that bleaching filtrates contain compounds interfering with the HPLC method.A strategy, dilution of the samples followed by treatment with activated carbon,was needed to obtain similar oxalic acid concentrations as provided by the reference method.The correlation(R=0.994) between the HPLC method and the IC method is described by the equation y=1.2947x.The method improves the possibility for control of critical (oxalic) acid concentration in closed-loop bleaching streams.
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    STUDY ON SYNTHESIS OF SULFONIC ROSIN-BENZYL-ESTER POLYMER AND ITS ADSORPTION FOR METAL IONS
    LAN Hong-yun;LEI Fu-hou;HUANG Jing-jing;PAN Pan;AN X in-nan
    2005, 25 (1):  29-32. 
    Abstract ( 624 )   PDF (777KB) ( 499 )   Save
    Sulfonic rosin-benzyl-ester polymer(SRBEP) was synthesized from rosin-benzyl-ester polymer and sulphuric acid.The content of—SO3H in SRBEP was measured,and the structure of the product was analysed by IR.The (adsorption) characteristics for metal ions Co2+,Cu2+,Pb2+ and reusability of SRBEP were discussed.The results showed that:SRBEP could well adsorb Co2+,Cu2+ and Pb2+,especially Co2+,Pb2+.Relative retention of the resin could be kept over 80% after reusing for 6 times.It could be used for separating and purifying of metal ions.
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    STUDY ON SYNTHESIS OF POLYPHENOL TYPE EPOXY RESIN FROM GALLIC ACID
    KONG Zhen-wu;HUANG Huan;YOU Zhi-liang;AN Xin-nan
    2005, 25 (1):  33-36. 
    Abstract ( 812 )   PDF (867KB) ( 872 )   Save
    The polyphenol type epoxy resin was synthesized by reacting epichlorohydrin with gallic acid,which was obtained from hydrolysis of plant polyphenols,and its chemical structure was characterized by IR,1H NMR and (13C NMR) spectra.The effects of material ratio and reaction time on ring-opening reaction,along with the effects of (reaction) temperature,reaction time,the dosage and concentration of sodium hydroxide on ring-closure reaction were (investigated) by chemical analysis and infrared spectrometry.According to the experiment results,the optimum reaction conditions were obtained as follows:1 mol gallic acid reacting with 20 mol epichlorohydrin at 100℃ for 6 h catalyzed by triethylbenzyl ammonium chloride,and then reacting with equivalent amount of solid alkali for 2 h at room (temperature).
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    A NEW ANGULAR FURANOFLAVONOL RHAMNOSIDE FROM SEEDS OF ZIZIPHUS JUJUBA VAR. SPINOSA(BUNGE) HU
    WANG Shao-min;BI Zhi-ming;LI Ping;YE Wen-cai;YI Ling;
    2005, 25 (1):  37-39. 
    Abstract ( 773 )   PDF (1423KB) ( 737 )   Save
    A new flavonol rhamnoside was isolated from the seeds of Ziziphus jujuba var. spinosa(Bunge) Hu.The process was as follows:70% EtOH extract of the seeds of this plant was successively partitioned with petroleum ether,ethyl acetate and n-BuOH;then the ethyl acetate fraction was subjected to silica gel column chromatography followed by Sephadex LH 20 column chromatography,to afford the compound.On the basis of spectral analysis and acid hydro-(lysis),the structure was confirmed to be an angular furanoflavonol rhamnoside,which is a novel compound,named (spinorhamnoside).
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    STUDY ON PREPARATION AND PROPERTIES OF E1-TYPE UF RESIN MODIFIED WITH MELAMINE
    JIN Li-wei;WANG Chun-peng;ZHAO Lin-wu;LIU Yi;JIANG Yu
    2005, 25 (1):  40-44. 
    Abstract ( 840 )   PDF (919KB) ( 1823 )   Save
    Effects of preparation technology of urea-formaldehyde resin modified with melamine(MUF)on property of plywood were studied.Results showed that formaldehyde emission of plywood conformed to E1 degree(≤1.5 mg/L) when formaldehyde/urea molar ratio was 1.1:1 and F/U molar ratio in weak acid stage was lower than 1.6:1.The bond strength of plywood using MUF resin in which content of melamine was beyond 3% did not satisfy to the requirement of type Ⅱ plywood (0.7 MPa).It was possible to decrease formaldehyde emission and improve bonding strength by adding 1% isocyanate curing agent in curing stage.Plywood,decorative plywood and blockboard manufactured with this MUF resin conformed to E1 degree required by standard.
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    POLYURETHANE/LINSEED OIL COMPOSITE COATING MODIFIED BY CASHEW NUT SHELL LIQUID
    WANG Hong-yu;WANG De-ning
    2005, 25 (1):  45-48. 
    Abstract ( 635 )   PDF (788KB) ( 896 )   Save
    By mixing castor oil (CO) with toluene diisocyanate (TDI) in linseed oil (LO) as dispersion medium, a composite coating of polyurethane (PU)/LO was prepared when cobalt naphthenate was used as drier.The solidified film was measured by IR,DSC and TEM.Results indicated that LO domains were dispersed in the continuous PU phase.The dispersion was then modified with cashew nut shell liquid (CNSL) containing hydroxyl groups.Tgs of both phases were increased after adding CNSL,and hardness of the paint film was enhanced.Furthermore,the dispersion was modified with coupling agent to improve adhesion property.
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    PREPARATION AND CHARACTERIZATION OF CELLULOSE ACETATE WITH HIGH DEGREE OF SUBSTITUTION AND HIGH CRYSTALLINITY
    WANG Neng;DING En-yong
    2005, 25 (1):  49-52. 
    Abstract ( 805 )   PDF (696KB) ( 1294 )   Save
    The new cellulose acetate of high degrees of substitution and crystallinity was prepared by acetylation of microcrystalline cellulose(MCC) in the heterogeneous system through distillation under reduced pressure.The degrees of substitution and crystallinity of the cellulose were 1.85 and 67%,respectively.The characteristics of this cellulose acetate was analyzed by FT-IR,X-ray and TGA.The results show:of high degree of substitution,the cellulose acetate prepared in heterogeneous system not only has much higher crystallinity than those prepared in quasi-homogeneous system,but also keeps the crystal form of cellulose I and has high thermal stability.
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    STUDY ON THE COPOLYMERIC COATING OF TERPENE-CATECHOL WITH RAW LACQUER(Ⅰ) ——Synthesis of terpene-catechol functional resin and its separation from terpene resin
    LEI Fu-hou;LAN Hong-yun;YAO Xing-dong;MENG Xiao-bo;AN Xin-nan
    2005, 25 (1):  53-55. 
    Abstract ( 624 )   PDF (411KB) ( 537 )   Save
    Synthesis of terpene-catechol resin from terpene resin and catechol was reported in this paper.Results showed that terpene-catechol resin could be synthesized directly with the proposed method.The synthesized terpene-catechol resin could be separated from terpene resin and catechol on neutral alumina column with petroleum,absolute ethanol and 5% NaOH-ethanol solution as eluates.Anion exchange resin was not suitable for the separation as stationary phase due to the strong adsorption toward catechol.The chemicals of eluates were measured by UV and IR. Terpene-catechol resin can be used for preparing copolymeric coating from terpene-catechol resin with raw lacquer.
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    SELECTIVE SYNTHESIS OF XYLANASES FOR PULP BIOBLEACHING BY TRICHODERMA REESEI RUT C-30
    MAO Lian-shan;YONG Qiang;YAO Chun-cai;YU Shi-yuan
    2005, 25 (1):  56-60. 
    Abstract ( 603 )   PDF (617KB) ( 578 )   Save
    Effects of carbon resource,culture temperature,initial pH value and carbon-to-nitrogen ratio on xylanase and cellulase synthesis by Trichoderma reesei Rut C-30 have been investigated.The results show that the mixture of corncob xylan and sulfite pulp as carbon resource could stimulate the synthesis of xylanase and cellulase;The culture temperature of 25-26℃ could stimulate the synthesis of xylanase and cellulase,the highest xylanases activity((156.53 IU/mL)) and CMCase activity(0.589 IU/mL) could be obtained after 96 h cultivation;When culture temperature was 35-36℃,the highest xylanase activity(113.73 IU/mL) and CMCase activity(0.208 IU/mL) could be obtained after 48 h cultivation;Low initial pH value could stimulate the synthesis of cellulase,whereas high initial pH value could prolong culture time of xylanase synthesis and depress the synthesis of cellulase.When the initial pH (values) were 4.0,4.4,4.8,5.4,6.0,the ratios of xylanase to cellulase were 259,327,425,865,1016,respectively,(after) (72 h) cultivation;Low ratio of carbon to nitrogen could stimulate the synthesis of cellulase,and high ratio of carbon to nitrogen could not only retard the synthesis of xylanase,but also depress the synthesis of cellulase.In the controlled cultivation of T.reesei Rut C-30 with a mixture of 6.5 g/L corncob xylan and 0.5 g/L sulfite pulp as carbon source,high xylanase activity(186.93 IU/mL) and low CMCase activity(0.156 IU/mL) could be obtained after 6 days (cultivation).At the earlier stage,temperature was controlled to 35-36℃ with an initial pH value of 6.0 and higher (ratio) of carbon to nitrogen(7.2),while at the later stage temperature was reduced to 25-26℃.
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    THERMOGRAVIMETRIC ANALYSIS ON FIRE RETARDANCE OF P-N INTUMESCENT FLAME RETARDANT
    HU Yun-chu;LIU Yuan;SUN Han-zhou;ZHOU Ying;WU Zhi-ping;YUAN Guang-ming
    2005, 25 (1):  61-65. 
    Abstract ( 606 )   PDF (1105KB) ( 954 )   Save
    Intumescent flame retardant is intensely concerned owing to its high efficiency and low toxicity.The synthesis conditions of phosphoryl amide type P-N intumescent flame retardant from diaminobisphenol A with phosphorus oxychloride and melamine were studied.The fire retardance of P-N intumescent flame retardant on poplar wood was studied by thermogravimetric analysis and burning test.The results showed that the yield of P-N intumescent flame retar-(dant) is high and the quality is optimal as the mole ratio of diaminobisphenol A,phosphorus oxychloride and melamine is 1:3:8 in ether for 5 h.The results by thermogravimetric analysis showed that the peak temperature and activation energy in the charring step decreased and charcoal yield increased from 22.5% to 36.3%,or increasing rate of 61.3%,on poplar wood treated by P-N intumescent flame retardant.The results of the burning test showed that the burning weight loss of poplar wood treated by P-N intumescent flame retardant is higher than control under 230℃,while charcoal yield is higher than control over 230℃.Charcoal yield at 350℃ increased from 24.9% to 38.4%,or increasing rate of 54.2%, and the charcoal yield at 600℃ increased from 7.3% to 22.3%,or increasing rate of 205%,on poplar wood treated by P-N intumescent flame retardant.The burned residue is black foamed charcoal with metallic gloss,showing that the flame retardant can efficiently promote formation of charcoal from wood to form graphitized foam layer.
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    PREPARATION OF ACTIVATED CARBON WITH HIGH SPECIFIC SURFACE AREA FROM CORN COB
    CAO Qing;LÜYong-kang;BAO Wei-ren;XIE Ke-chang
    2005, 25 (1):  66-68. 
    Abstract ( 688 )   PDF (619KB) ( 891 )   Save
    A simple,feasible route for utilizing agricultural waste corn cob to prepare activated carbon of high specific surface area has been studied,using KOH as activating agent.The results show that the formation of micro-pore with high specific surface area can be influenced by many factors such as carbonization temperature,heating rate,activating time and the proportion of mKOH/mC,the optimal conditions of which are 850℃ for activating temperature,450-600℃ for carbonization temperature,1.2 h for activating time,3:1-5:1 for mKOH/mC when the heating rate is 30℃/min.In addition,the activating way can also obviously affect the specific surface area of the activated carbon.The structure of activated carbon prepared has narrow pore size distribution and nearly no hysteresis phenomenon is observed.
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    STUDIES ON LAYER COMPOSITES OF WHEAT STALK AND THEIR ADHESION PROPERTIES
    LIAN Hai-lan;ZHOU Ding-guo;YOU Ji-xue
    2005, 25 (1):  69-72. 
    Abstract ( 694 )   PDF (747KB) ( 1305 )   Save
    Wheat straw was split into layers,and the chemical composition of each layer was analyzed by chemical and modern instrumental analysis for the purpose to find the differences among layers.Following to the specific characteristics of the outer layer,7 different coupling agents were used to explore the variation of adhesion properties.Results showed that outer layer accounts for 20% thickness of the whole stalk and containes somewhat different contents of components,in which ash content is 21.95% higher than that of the whole stalk,while SiO2 content in its ash is more than 100% higher than the whole stalk;and phenol-EtOH extractive is 21.95% higher than the whole stalk.ESR (analysis) indicated that free radicals in the whole stalk is higher than outer layer.SEM results demonstrated the smooth cuticle surface of the outer layer,as well as the absence of cuticle on inner layer,and the later is beneficial to wetting,diffusion and permeation of UF resin.The coupling agent KH-550 exhibited good adhesion property toward each layer of the stalk,especially the significant increase of bonding strength toward outer surface,while other coupling agents showed no significant effect.
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    STUDIES ON LACCASE PRODUCTION BY CORIOLUS VERSICOLOR AND ENZYMATIC DECOLORATION OF DYE
    LU Rong;SHEN Xue-liang;XIA Li-ming
    2005, 25 (1):  73-76. 
    Abstract ( 611 )   PDF (792KB) ( 828 )   Save
    Laccase production by a white-rot fungus Coriolus versicolor was studied under submerged fermentation (condition).The optimal fermentation parameters were as follows:carbon source 1.1 g/L sucrose combined with 1.1 g/L glucose,nitrogen source 1.88 g/L bean cake powder,culture temperature 30℃ and initial pH value 4.5.The activity of laccase reached 18.2 U/mL.The optimum reaction temperature of laccase was 60℃,and laccase was stable when the environmental temperature was below 55℃.Considering the thermal stability of laccase,the suitable temperature for the enzymatic application was 55℃.The laccase produced by C. versicolor could hydrolyze and decolorize aromatic dye.During the decoloration of acid orange dye with laccase,the addition of redox mediators could obviously increase the catalytic ability of the enzyme.The decoloration rate of acid orange dye could reach 96.5% after 5 h,which showed a good application potential in environment protection.
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    STUDY ON ADSORPTION OF FORMALDEHYDE BY BAMBOO CHARCOAL
    YANG Lei;CHEN Qing-song;LAI Shou-lian;LI Xiao-yan;YE Gui-zu
    2005, 25 (1):  77-80. 
    Abstract ( 787 )   PDF (844KB) ( 1317 )   Save
    Amount of formaldehyde vapor adsorbed by bamboo charcoal was determined by spectrophotometry and the relations among adsorption amount,time and temperature were studied.Furthermore,the mechanism of formaldehyde adsorption and desorption on bamboo charcoal was discussed and the measuring method of formaldehyde adsorption was established.From SEM pictures of bamboo charcoal,the influence of particle size on amount of formaldehyde adsorption was investigated.The results showed that,under the adsorption condition of 55℃ and 3 h,the adsorption (amount) of formaldehyde on bamboo charcoal was maximal,up to 68.5 mg/g.Bamboo charcoal particle size has some effects on amount of formaldehyde adsorption but not obvious,which is mainly caused by its microstructure.The adsorption is mainly physisorption,so the desorption happens quite easily.In the process of desorption,the relation (between) the residual of formaldehyde and time follows the equation y=109.19x-1.1084,at correlative coefficient r=0.979 4.
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    STUDY ON MICROWAVE-ASSISTED EXTRACTION OF BAICALIN FROM SCUTELLARIA BAICALENSIS
    CHENG Cun-gui;JIN Wen-ying;WU Lan-ju
    2005, 25 (1):  81-83. 
    Abstract ( 633 )   PDF (455KB) ( 1014 )   Save
    A new method,namely microwave-assisted extraction(MAE),is used to extract baicalin from S. baicalensis.Water,ethanol,chloroform,n-hexane,petroleum were used separately to extract baicalin in a MAE apparatus.The result showed the optimum condition as follows:60% alcohol as sovent,granularity of raw material 200 mesh,duration of microwave irradiation 8 min.Effects of different solvents,different grain sizes of S. baicalensis Georgi and duration of microwave irradiation on yield of baicalin were discussed.Results showed that microwave-assisted extraction is (efficient),simple and rapid for extraction of baicalin from S. baicalensis.
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    STUDY ON RELATIONSHIP BETWEEN THE PRESERVATION METHOD OF ROSE FLOWERS AND THE YIELD OF ESSENTIAL OIL
    MA Xi-han;WANG Yong-hong;WEI Qin;ZHANG Guang-jun
    2005, 25 (1):  84-88. 
    Abstract ( 575 )   PDF (813KB) ( 1103 )   Save
    A methodological study was carried out on the preservation of rose flowers.Several methods were tested (according) to practical conditions.It was found that preservation of rose flowers within a short period in package bags was an economic and practical method with advantages of narrow changes of temperature,smell and color,it could preserve rose flowers as long as 24 h.Spreading fresh flowers on the indoor concrete floor is also a suitable way,by which the temperature of the flowers does not increase.The yield of essential oil could be increased by 20% after the flowers were spread for 6 h due to post-rippening effect.However,the yield decreased after 6 h spreading due to the emanation of essential oil into air.Refrigerated flowers can also be stored for a long time without change of essential oil yield.Salt-impregnated flowers can be preserved for a long time.The suitable salt dosage is 15% of the weight of flowers.
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    DISTRIBUTION OF TAXOL AND TAXANES IN YEW TREE
    ZHAO Chun-fang;YU Long-jiang;LIU Zhi;SUN You-ping;LI Wen-bing
    2005, 25 (1):  89-93. 
    Abstract ( 781 )   PDF (938KB) ( 958 )   Save
    The contents of taxol and its two important precursors,namely baccatin III(B III)and 10-deacetylbaccatin III (10-DAB) in various tissues of yew trees Taxus chinensis(Pilg.)Rehd. at different ages in different seasons were quantified by HPLC.The results indicated that the content of taxol decreased successively according to stem barks,root barks,lateral stem barks,seeds,fibres,twigs and young needles in a single tree.The gradient distribution of taxol concentration along radial direction of cross section of lateral stem was surveyed for the first time.It was found that the highest amount of taxol occurred in the secondary xylem rather than in the cortex of the lateral stem.The highest and the lowest contents of 10-DAB and B III among the parts of a tree occurred in needles and fibres,respectively.The content of 10-DAB in needles was in a range of 0.01% to 0.02%,higher than that of B III and taxol.The result of the absence of both taxol and related taxanes in needles from 2-3 years old yew tree indicated that the biosynthesis of taxanes may require related phase of the development of the plant.It was observed that the mature needles in the spring have higher amount of taxol than in autumn,while the case of 10-DAB was in reverse.The mechanisms of (biosynthesis) and accumulation of taxol were discussed through the analysis of the distribution of taxol and related (compounds) in T.chinensis(Pilg.)R.
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    STUDY ON SYNTHESIS OF HYBRID EMULSION OF CASTOR OIL WATER-BORNE POLYURETHANE-ACRYLATE
    QU Jin-qing;CHEN Huan-qin
    2005, 25 (1):  94-98. 
    Abstract ( 655 )   PDF (622KB) ( 830 )   Save
    Hybrid emulsion of castor oil polyurethane-acrylate(CPUA) was prepared by co-polymerization of castor oil polyurethane with methylacrylate(MMA).The effects of castor oil content,initiator type and MMA content on the properties of CPUA emulsion and its film were investigated.The structure of CPUA was characterized by FT-IR.It was found that mechanical properties and water resistance of CPUA coating film and average particle size of CPUA (emulsion) increased,and viscosity of CPUA emulsions and glossiness of CPUA film decreased with increasing of MMA and castor oil contents,the optimal MMA and castor oil contents were determined to be 20%-33% and 20%-25%,respectively.Using azo-bis-isobutyronitrile(AIBN) and potassium persulfate(KPS) as composite initiator (increased) the monomer conversion.The property-tests show that CPUA exhibits the films of excellent mechanical (properties) and good water-resistance.
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    STUDY ON COMBINATED PURIFICATION OF TEA POLYPHENOLS AND THEANINE
    CHEN Rong-yi;ZHANG Xin-shen;SHEN Jin-shan;LI Xiao-yan;XIE Jun;
    2005, 25 (1):  99-101. 
    Abstract ( 699 )   PDF (627KB) ( 1220 )   Save
    Theanine and tea polyphenols were purified from the extract of green tea with ZJL macroporous cation resin column followed by ZJX macroporous adsorption resin column chromatography,at the same time caffeine was removed effectively.The optimal operating conditions were obtained through static and dynamic state experiments.Extraction yield and purity of theanine were 0.94% and 85.43%,respectively.Yield and purity of tea polyphenols were (12.35%) and 95.62%,respectively,and the content of caffeine in tea polyphenols product was less than 0.8%.
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    PREPARATION OF TERPENE-RESIN EMULSIONS
    WU Zong-hua;CHEN Shao-ping;LI Ai-min;LU Yu-dong
    2005, 25 (1):  102-104. 
    Abstract ( 1020 )   PDF (512KB) ( 820 )   Save
    Series terpene-resin emulsions were prepared using polymeric surfactants designed for the emulsions.The results showed that hydrophile-lypophile balance(HLB) values could be used as the design basis to determine monomer ratios in the polymeric surfactants,HLB value of terpene-resins in this study was 13.Solvent was used to decrease melting temperature and time of the resin during emulsification.The structures and amounts of the polymeric surfactants influenced greatly the emulsification results.The polymeric surfactant with mass ratio of styrene,acrylamide and monomer 3 at mass ratio 1:0.6:0.2 was a good emulsifier for the terpene resins(T-90,T-100,T-110).The amount of the surfactant used in the emulsification was 10%.
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    EFFECT OF HEAT TREATMENT ON MICROSPHASE SEPARATION OF BENZYLATED-WOOD-BASED POLYURETHANE
    LI Hou-ping;CHENG Fa;WEI Yu-ping;PAN Hong
    2005, 25 (1):  105-108. 
    Abstract ( 732 )   PDF (742KB) ( 875 )   Save
    Polyurethane resin was synthesized by benzy lated wood solution using mixture of dibasic esters(DBE) and n-butylacetate as solvents with the adduct of toluene diisocyanate(TDI) and trihydroxyme thylpropane, and then the resin was treated by different heating methods. FT-IR, DSC, DTA and TG are used to characterize the resin. All results showed that heat treamtent method plays an important role on microsphase separation and therm al property of theresin. The degrees of microphase separation under different heat treatment methods are in the sequence of: norm al temperature so lidifying(S) > annealing (A) > quenching (Q). The initial decomposing temperatures during hard-stage are in the sequence of S> A > Q, while the initial decomposing temperatures during soft-stage are in the sequence of:S< A < Q.
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    GC-MS ANALYSIS OF VOLATILE OIL COMPONENTS OF ROOTS OF TRICHOSANTHES KIRILOWII MAXIMO.
    HU He-jiao;WANG Hong;PAN Yuan-jiang
    2005, 25 (1):  109-111. 
    Abstract ( 590 )   PDF (344KB) ( 646 )   Save
    The root of Trichosanthes kirilowii Maximo.was extracted by 95% ethanol,then the thickened solution was extracted with petroleum ether.The essential oil was obtained by steam distillation,then separated by capillary gas chromatography,and 128 components were separated.Among them,45 compounds were identified and their relative contents account for 82.75% of the total peak area.
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    STUDY ON MICROWAVE PRETREATMENT OF RICE STRAW IN SACCHARIFICATION PROCESS
    ZHU Sheng-dong;WU Yuan-xin;YU Zi-niu;LI Hui;ZHANG Xia
    2005, 25 (1):  112-114. 
    Abstract ( 698 )   PDF (419KB) ( 978 )   Save
    The saccharification processes of rice straw were investigated using three different microwave irradiation treatment methods.The results showed that rice straw pretreated by combining microwave irradiation with alkali treatment together was the most favorable approach for saccharification of rice straw under this test condition.The effects of microwave irradiation power and irradiation time on saccharification was examined and the saccharification conditions were optimized by an orthogonal test.The optimal saccharification conditions were:substrate concentration 10 g/L,temperature 45℃,pH value 4.8 and enzyme loading 20 mg/g substrate.
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    ADVANCES OF RESEARCH ON MOLECULAR BIOLOGY OF LACCASE FROM FUNGI
    ZHAO Min;YANG Qian;SONG Xiao-shuang;LIU Gui-feng
    2005, 25 (1):  115-120. 
    Abstract ( 638 )   PDF (747KB) ( 817 )   Save
    This text summarizes recent advances of research on molecular biology of laccase,including its physicochemical properties,sequence analyze of amino acids,gene clone,gene-structure analysis and tissue analysis,gene family,regulation of gene expression and heterologous expression.
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