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Table of Content

    30 September 2003, Volume 23 Issue 3 Previous Issue    Next Issue
    研究报告
    CHARACTERIZATION OF CARDANOL-ALDEHYDE CONDENSATION POLYMER CONTAINING COPPER-NITROGEN COORDINATED BOND
    CHEN Yu;LIN Jin-huo
    2003, 23 (3):  61-64. 
    Abstract ( 703 )   PDF (900KB) ( 638 )   Save
    Cardanol aldehyde condensation resin(CF) is susceptible to corrosion by alkali because of its slight acidity of phenolic hydroxyls.CF was modified by aniline, followed by reaction with CuCl2.The final product of the co condensation polymer containing copper nitrogen coordinated bond(CFNCu) has been synthesized and characterized by IR, dynamic mechanical thermogram analysis(DMTA) and other measures.Results show that copper nitrogen coordinated bond increases the cross linking of coating film, leading to the remarkable improvements of physico mechanical properties, thermo stability and resistance against chemical media, especially alkali.
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    STUDY ON TECHNOLOGY OF EXTRACTING AUCUBIN FROM EUCOMMIA
    PENG Mi-jun;ZHOU Chun-shan;ZHONG Shi-an;LEI Qi-fu;DONG Chao-qing
    2003, 23 (3):  65-68. 
    Abstract ( 571 )   PDF (936KB) ( 678 )   Save
    The optimum technology of extracting aucubin, the bioactive component in Eucommia ulmoides, was studied by orthogonal test. An orthogonal test table L16(45) was used with the factors of extracting time, temperature, times, ethanol concentration and the ratio of solid to liquid.The content of aucubin was determined by spectrophotometry.The optimum technology was:temperature 70℃, time 0.5 h, three times, 80% EtOH as extracting solvent, stock ratio 1:9.Under this condition, the best raw material of E.ulmoides for extracting aucubin was chosen, namely the freshly dried bark.
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    STUDY ON EXTRACTION AND CHARACTERIZATION OF WATER-SOLUBLE TEA GREEN PIGMENT
    YANG Xiao-ping;GUO Da-yong
    2003, 23 (3):  69-72. 
    Abstract ( 612 )   PDF (624KB) ( 761 )   Save
    Water soluble tea green pigment(TGP) were extracted from low grade tea leaf and waste tea etc.Physico chemical properties and processes on saponification and copper substitution reaction were investigated.Results showed that optimum condition of saponification is sodium hydroxide 1% for 90 min, temperature of water bath 80℃.At pH value 3.0, temperature of water bath 80℃ for 60 min, a high proportion sodium copper chlorophyllin was achieved.The pH value in the range of 2.2-5.0 had no effect on the pigment.Heat and most of metal ions exerted insignificant effect, while ascorbic acid had protective effect on the tone of pigment.
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    STUDY ON TECHNIQUE UPON ISOLATION AND PURIFICATION OF CHLOROGENIC ACID FROM LEAVES OF EUCOMMIA
    MA Xi-han;WEI Qin;JING Qian-ping
    2003, 23 (3):  73-76. 
    Abstract ( 661 )   PDF (755KB) ( 869 )   Save
    Based on the previous study, chlorogenic acid was isolated and purified from leaves of Eucommia ulmoides Oliver in an pilot scale experiment by the following process:refluxing by 40% ethanol(80℃, 2 h, ratio of material to solvent:1:16, extract twice)extracts preparation(vaccum evaperation, drying at 80℃)extraction by water(4 times)precipitation by Pb(OAc) 2\resolution of chlorogenic acid by 20% sulfuric acidextraction by ethyl acetate(20 times)condensationre crystallization.The yield of chlorogenic acid is 0.53%, at purity 98.35%.Results of the experiment showed that this technological process was feasible and practical.It was found that no isomers of chlorogenic acid occurs in the leaves of E.ulmoides after comparing with honeysuckle flowers and raw coffee beans, in which the occurrence of iso-chlorogenic acids was reported.This is traceable to the views of secondary metabolism and chemical reaction.
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    STUDY ON TECHNOLOGY OF MANUFACTURING ACTIVATED CARBON FROM TOBACCO STEMS IMPREGNATED WITH ZnCl2 SOLUTION BY MICROWAVE RADIATION
    ZHANG Li-bo;PENG Jin-hui;ZHANG Shi-min;FAN Xing-xiang;GUO Sheng-hui
    2003, 23 (3):  77-80. 
    Abstract ( 733 )   PDF (572KB) ( 830 )   Save
    Factors influencing properties of wooden activated carbon such as microwave radiation power, radiation time and flow rate of water vapor were systematically studied via orthogonal experiments.Optimum technology was obtained as follows:microwave radiation power 700 W, radiation time 6 min and flow rate of water vapor 3.09 mL/min.Results showed:yield of wooden activated carbon 20.74%, decolorization for methylene blue 160 mL/g, iodine adsorption 1018.7 mg/g.Microstructure of the wooden activated carbon resembled the shape of honeycomb, which extends inward.Also many superfine holes are available in the wall as channels to connect them together.Compared with that of the first graded activated carbon in the market, it was found that the activated carbon manufactured by microwave radiation possesses a more developed microporous structure.
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    MICROWAVE EXTRACTION OF ARABOGALACTAN FROM WOOD
    FANG Gui-zhen;HUANG Zhan-hua;LI Shu-jun;JIN Zhong-ling
    2003, 23 (3):  81-84. 
    Abstract ( 655 )   PDF (834KB) ( 720 )   Save
    Arabogalactan was extracted from wood flour of Larix gmelinii Rubr.with water under microwave radiation.Effects of microwave power, extraction time, wood flour particle size and ratio of solid to liquid on the yield were investigated.Optimum extraction parameters were obtained as follows:490 W microwave power, 25 min, 1:35 ratio of solid to liquid(by mass), 0.20-0.30 mm wood flour particle size.Under these conditions, the extraction yield was 17.47%, which was 1.6% higher than that from the traditional water bath extraction.Extraction time by the new method was just 1/12 of that by the traditional method.FTIR spectra analysis indicated that structural characteristics of the extractives obtained under microwave radiation were almost identical to those from the traditional method.
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    DETERMINATION OF IMPURITY CONTENT IN INDUSTRIAL DIETHANOLAMINE BY GAS CHROMATOGRAPHY
    ZHANG Song-hong;ZHANG Yuan-chang
    2003, 23 (3):  85-87. 
    Abstract ( 748 )   PDF (536KB) ( 1516 )   Save
    A facile and rapid method for the determination of ethanolamine(EA) and triethanolamine(TEA) in diethanolamine (DEA) by using hydrogen flame ionization detector has been developed.It was operated on a HP-5 30 m×0.32 mm×0.25 μm capillary column.Triethylene glycol(TEG) was used as internal standard.The average recoveries were from 93.17% to 101.50%, at relative standard deviations from 1.54% to 2.15%.
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    综述评论
    APPLICATIONS OF LIGNIN IN THE FIELD OF POLYMERS
    CHU Fu-qiang;HONG Jian-guo
    2003, 23 (3):  88-92. 
    Abstract ( 866 )   PDF (679KB) ( 2398 )   Save
    Lignin, which exists as high polymer in plant, is a sort of environment friendly and reproducible natural resource, whose reserves in the world is next to cellulose.However, man has not made the most of it as yet.This article reviews the exploratory development of utilizing lignin in macromolecule field, which mostly includes synthesizing lignin phenol formaldehyde resin adhesives, polyurethane, polymerizing with epoxide as well as graft copolymerizing with vinyl monomer.Although these studies have taken some positive results, there is still the technology gap to carry through upon using lignin as one of raw material in high polymer industry.It has been gradually realized that measures to decrease the polydispersity and increase the reactivity of lignin may be the key to achieve the breakthrough in this field.
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    ADVANCES IN THE STUDY OF CELLULOSE SPONGE PRODUCTS
    LI Cui-zhen;HU Kai-tang;YU Zhi-wei
    2003, 23 (3):  93-96. 
    Abstract ( 656 )   PDF (423KB) ( 1250 )   Save
    Cellulose sponge product which is made from cellulose through somewhat methods, is analogous to polyurethene sponge.Methods of manufacturing cellulose sponge product and its development were briefly reviewed.Of these methods, the methods of hydrolyzation of xanthate cellulose, hydrolyzation of cellulose acetate and N-methylmorpholine are described in detail.
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    PROGRESS ON SYNTHESIS OF CITRONELLOL
    RAN Xue-guang;JIANG Huan-feng;ZHU Xin-hai;CHEN Wei-qiang
    2003, 23 (3):  97-101. 
    Abstract ( 927 )   PDF (498KB) ( 1828 )   Save
    Citronellol is a common perfume material, and research of citronellol is of great economic value.Citronellol occurs in more than 70 essential oils in nature.Synthetic methods of citronellol, including semi synthesis from natural products and total synthesis from fossil resources, are introduced inclusively.Descriptions on methods for synthesizing citronellol from DHM are focussed in detail.Advantages and shortcomings of different methods and their production technology are also described.
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    研究简报
    STUDY ON PHYSICO-CHEMICAL PROPERTIES OF THE PIGMENT IN FLOWERS OF MALLOW
    WANG Zhen-yu;YANG Qian
    2003, 23 (3):  102-104. 
    Abstract ( 558 )   PDF (522KB) ( 645 )   Save
    Physico chemical properties of red pigment in flowers of mallow(Malva sylvestris L.var. mauritiana Miller were investigated.Results showed that the red pigment from M.sylvestris L.var. mauritiana Miller is classified to anthocyanins.The pigment is soluble in water, slightly soluble in alcohol and trichloromethane, and insoluble in benzene, toluene, ether, petroleum ether and dichloromethane.pH value had significant effect on the tone of pigment.Metallic ions Na+, Cu2+, Fe3+, Zn2+ had effect on the tone of pigment while K+ and Fe2+ had no effect on the tone of pigment.Under natural light, degradation of the pigment could be accelerated, while ultraviolet light had no effect on the pigment.
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    STUDY ON THE CONDITIONS UPON DECOLORATION OF INSECT WHITE-WAX BY ORTHOGONAL OPTIMIZATION
    DUAN Qiong-fen;SUN Long;ZHAO Hong;CHEN Wei-cheng;CHEN Xiao-ming
    2003, 23 (3):  105-106. 
    Abstract ( 808 )   PDF (322KB) ( 552 )   Save
    Decoloration conditions of insect white wax was studied by orthogonal test.Effects of white clay dosage, decoloring temperature and time upon decoloration were investigated.Optimum decoloration condition was determined as follows:white clay dosage 8%, decoloring temperature 80℃ and time 30 min.
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    研究报告
    STUDY ON EFFECTS OF MODIFIED SULFITE SPENT LIQUOR UPON SANDY SOIL STRUCTURE
    LI Jian-fa;ZHOU Yong-hong;WANG Zhan-jun;ZHONG Yun-you;SONG Zhan-qian
    2003, 23 (3):  1-5. 
    Abstract ( 548 )   PDF (519KB) ( 687 )   Save
    Spent sulfite liquor(SSL) from bagasse pulping was modified by graft copolymerization of acrylic acid(AA) and/or acrylamide(AM) onto lignosulfonate.Effects of SSL and different modified products upon sandy soil structure were studied.At the application rate of 0.2%, the dry contents of stable aggregates(>0.25 mm, COAs) in sandy soil samples treated with AA and AM modified products were 49.4% and 48.9%, and wet COAs were 38.1% and 39.9%, respectively.Among the products modified with both monomers, the product with AA/AM ratio of 20/80 had the best performance on improving structure of sandy soil.The acting mechanisms of polymer on soils were reviewed.It was suggested that, at dry status the bonding of anionic groups onto sand grains was stronger than that of non-ionic groups, and there might be adhesion between polymers and sandy soils.
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    STRUCTURAL IDENTIFICATION OF THE PRODUCTS FROM NOPOL OZONIZATION BY GC-MS
    WANG Zong-de;XIAO Zhuan-quan;CHEN Jin-zhu
    2003, 23 (3):  6-10. 
    Abstract ( 606 )   PDF (628KB) ( 634 )   Save
    Nopol was ozonized in methanol and ethanol respectively, followed by reductive hydrolyzation and GC MS analysis.The MS data was analyzed, and structures of6 main products have been identified, namely:cis-2, 2-dimethyl 3-(β-hydroxypropionyl) cyclobutaneethanal, 3 hydroxy cis-2, 2-dimethyl 3-(β-hydroxypropionyl) cyclobutaneethanal, 1 hydroxy cis-2, 2-dimethyl 3-(β-hydroxypropionyl) cyclobutaneethanal, cis cis-2, 2-dimethyl 3-(β-hydroxypropionyl) cyclobutaneacetaldehyde dimethyl acetal, cis-2, 2-dimethyl 3-(β-hydroxypropionyl) cyclobutaneacetaldehyde diethyl acetal and 2, 2-dimethyl 3-(β-hydroxypropionyl) butanone.The results showed:1)The 6 main products are all four member ring compounds produced through the cleavage of double bond of nopol;2)Accompany with oxidations of the double bond and tertiary hydrogen in the ozonization, there are other reactions at more in depth levels.
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    STUDY ON PREPARATION OF HIGH-PURITY NATURAL d-BORNEOL
    SONG Yong-fang;LUO Jia-liang
    2003, 23 (3):  11-14. 
    Abstract ( 675 )   PDF (1159KB) ( 1443 )   Save
    Crude d-borneol was obtained by water vapor distillation and sublimation from leaves of Cinnamomum glanduliferum (Wall) Nees.In order to prepare high purity d-borneol, experiments were carried out to investigate the effects of different solvent, solvent amount, times of crystallization and crystallizing time.High purity d-borneol was analyzed by GC and GC/MS, and crystal of d-borneol was examined by scanning electron microscopy(SEM).Results showed that gasoline is the best solvent for crystallizing d-borneol, purity of d-borneol product was over 99% using material:solvent ratio 1:1.7-2.0, and crystallizing time 4 days.Analytical data of the fine natural d-borneol products are:appearance of white slice crystals, d-borneol content>99%, optical rotation [α]D20>+37, melting point 205-209℃, heavy metals content <5 millionth and arsenide(As) content<2 millionth.
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    PHARMACOLOGY OF POLYPRENOLS FROM GINKGO BILOBA L.LEAVES IN COMBINATION WITH CHEMOTHERAPEUTIC DRUGS ON TUMOR
    WANG Cheng-zhang;SHEN Zhao-bang;GAO ling
    2003, 23 (3):  15-18. 
    Abstract ( 746 )   PDF (715KB) ( 740 )   Save
    Pharmacology of polyprenols from Ginkgo biloba L.leaves(GP) in combination with chemotherapeutic drugs on tumor was studied.Polyprenols separated and purified from G.biloba L.leaves were administered in combination with adriamycin(ADM), 5-flauouracil(5-Fu), cyclophosphamide(CTX) and cisplatin(PDD) respectively, in contrasting with ADM, 5-Fu, CTX and PDD alone.Experiments were carried out on mouse with transplanted S180.Results show that for polyprenols in combination with CTX, PDD and 5-Fu, the inhibition of S180 nodule was raised from 59.81%, 43.06% and 42.03% to 70.56%, 60.29% and 63.45% respectively, in contrasting with their administration alone.For ADM in combination with polyprenols, 1.0 mg/kg ADM had raised the inhibition of S180 nodule from 50.93% to 77.19%.Results showed that polyprenols have a significant subsidiary effect on chemotherapy, along with reduced toxicity.
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    STUDY ON DEINKING OF THE USED NEWSPRINT WITH BLENDED CELLULASE/XYLANASE
    GU Qi-ping;YONG Qiang;YE Han-ling;YOU Ji-xue
    2003, 23 (3):  19-22. 
    Abstract ( 632 )   PDF (582KB) ( 677 )   Save
    Cellulase blended with xylanase at certain ratio was used for deinking of the used newsprint to obtain their optimal ratio and compared with chemical deinking.Results showed 50/50 was the optimum ratio, under which the brightness of deinked pulp is 3.2 percentages higher and ink removal rate is 73.8% lower respectively than the contrast, and 0.4 percentages higher and 8.6% lower respectively than the xylanase deinked pulp.Breaking length, bursting index and tearing index were 3.8%, 5.9% and 8.6% higher than those of cellulase deinked pulp respectively.Enzyme dosages were saved 50% for cellulase and xylanase both, too.Compared with chemical deinked pulp, enzymatic deinked pulp had higher yield and lower postcolor number.
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    STUDY ON STRUCTURE AND BLOOD-ANTICOAGULATING ACTIVITY OF TWO SODIUM CELLULOSE SULFATES
    WANG Zhao-mei;LI Lin;HU Song-qing;FENG Zong-cai;GUO Si-yuan
    2003, 23 (3):  23-27. 
    Abstract ( 663 )   PDF (768KB) ( 697 )   Save
    The structure and blood anticoagulating activity of two sodium cellulose sulfates, i.e. Na-MCS and Na-CAS were studied.Na-MCS and Na-CAS were derived from microcrystalline cellulose(MC) and cellulose tri acetate(CTA) respectively by sulfation with ClSO3H-DMF.Structural measurement by IR spectra disclosed the presence of sulfate bond in both Na-MCS and Na CAS.Elemental analysis revealed that the substitution degree of Na-MCS and Na-CAS were 1.70 and 0.83 respectively.Further measurement of 13CNMR showed that the distribution of sulfate was complete substitution at C_6, partial substitution at C_2 in Na MCS and only patial substitution at C_6 in Na-CAS.Anti-coagulation investigation indicated that the re calcium time(RT) of whole blood, and the activated partial thromboplastin time(APTT) and throbin time(TT) of human plasma were prolonged when Na-MCS or Na-CAS was added. Compared with sodium heparin, the blood anticoagulating activity of Na-MCS was even stronger, while the anticoagulation activity of Na-CAS was much weaker than that of Na-MCS.
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    STUDY ON GRAFT COPOLYMERIZATION OF METHYL METHACRYLATE ONTO WOOD SURFACE AFTER MICROWAVE PLASMA TREATMENT BY XPS
    YANG Zhong;DU Guan-ben;HUANG Lin-rong;ZHANG Hua
    2003, 23 (3):  28-32. 
    Abstract ( 620 )   PDF (528KB) ( 692 )   Save
    Surface structure and properties of the untreated, treated and grafted wood were analyzed by X-ray photo electron spectroscopy(XPS).XPS spectra showed that:1)Microwave plasma treatment increased the O/C atomic ratio of the wood surface, diminished C1(carbon bonded to carbon and/or hydrogen), increased C2(carbon bonded to a single oxygen) and C3(carbon bonded to two non carbonyl oxygen or to a carbonyl oxygen), and generated C4(carbon bonded to a carbonyl and a non carbonyl oxygen).These results suggest that a great deal of oxygenated groups or peroxides were generated on wood surface after microwave plasma(MWP) treatment; 2)The O/C ratio of the grafted wood by MWP initiation was higher than that of untreated wood, but lower than that of treated wood by MWP;the main changes of C1s spectral peak of grafted wood were the generation of C4 intense peak, suggesting the generation of a good deal of O-C=O groups on wood surface; 3)The O1/O2 ratio of the grafted wood is about 1, higher than that of the untreated wood and treated wood by MWP, showing the considerable increase of C=O content in grafted wood.These results showed that a great deal of methyl methacrylate(MMA) molecules were grafted onto wood surface.
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    ELECTROCHEMICAL BLEACHING OF REED KRAFT PULP
    MA Zhi-jun;OU Yi-fang;YAN Bing
    2003, 23 (3):  33-36. 
    Abstract ( 665 )   PDF (628KB) ( 583 )   Save
    Electrochemical bleaching of reed kraft pulp employing a graphite plate anode and a stainless steel screen cathode adding K3Fe(CN) 6 as catalyst was carried out.Influences of current density, alkali charge, bleaching time, concentration of catalyst and pulp consistency on pulp Kappa number and viscosity were discussed.Experimental results indicate that the optimum condition for electrochemical bleaching of reed kraft was:current density 6.67 mA/cm2, alkali 0.4%, K3Fe(CN)612.50 mmol/L, pulp consistency 1.3% at 80℃ for 30 min.
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    STUDY ON ESTERIFICATION OF ROSIN WITH POLYOLS UNDER MICROWAVE RADIATION
    LIN Zhong-xiang;CHEN Ri-qing
    2003, 23 (3):  37-40. 
    Abstract ( 711 )   PDF (614KB) ( 1056 )   Save
    Glyceryl rosinate with acid value 8.3 mgKOH/g, Gardner color 8, softening point 82.0℃ and pentaerythritol rosinate with acid value 8.6 mgKOH/g, Gardner color 7, softening point 91.0℃ were prepared by esterification of rosin with glycerin or pentaerythritol respectively under microwave radiation using zinc oxide as a catalyst.Esterification of 20 g rosin with 2.4 g glycerin and 0.068 g zinc oxide or with 3.2 g pentaerythritol and 0.034 g zinc oxide could be finished under 650 W microwave radiation for 30 min in atmosphere pressure and then for 30 min in 5 kPa to give the optimized result.
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    PREPARATION AND APPLICATION OF NOVEL SOLID SENSOR MODIFIED BY POLYMERIC COMPOUND OF URUSHIOL-Fe
    YANG Chun-hai;SHI Bo-an
    2003, 23 (3):  41-44. 
    Abstract ( 551 )   PDF (715KB) ( 565 )   Save
    Solid sensor modified by urushiol Fe resin was prepared for the determination of trace copper in water.Mechanism of increasing sensitivity has been studied.In 0.1 mol/L KNO3 and HOAc NaOAc solution, peak current is linearly correlated with concentration over the range from 4×10-9 mol/L to 2.5×10-7 mol/L.Detection limit(signal to noise=3) is 8×10-11 mol/L after 20 min accumulation.Using the electrode, Cu2+ in water samples were detected, and average recovery is 99.10%.
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    ALLELOPATHIC STUDY OF WALNUT LEAF EXTRACTS
    XU Yao-ping;TANG Jing-cheng;GAO Jin-ming;Li Shi-an
    2003, 23 (3):  45-48. 
    Abstract ( 669 )   PDF (617KB) ( 865 )   Save
    The allelopathic effects of walnut(Juglans regia L.) leaf extracts on three plant acceptors:lettuce, wheat and tomato was explored by germination and growth experiments.Results showed that different concentrations of aquatic walnut leaf extracts had certain inhibitory and/or promoted effects on those acceptors, and major bioactive substances were found to be phenolics and flavonoids.This study can provide some basis for development of biorational pesticides.
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    STUDY ON EFFECTS OF NITROGEN AND PHOSPHORUS ON PERFORMANCE OF PULP WASTEWATER TREATMENT IN STABILIZATION PONDS
    WANG Qing;Lü Bing-nan;TENG Fei;ZHAO Jing-long
    2003, 23 (3):  49-52. 
    Abstract ( 634 )   PDF (539KB) ( 493 )   Save
    Effects of nitrogen and phosphorus on the performance of pulp wastewater treatment in stabilization ponds were studied.Result shows that there is a distinct effect in anaerobic ponds.As the hydraulic detention time increased, effects of nitrogen and phosphorus become insignificant.Two regression equations are formulated to express the relationship between the effluent COD and nitrogen and phosphorus, and the relationship between the substrate removal rate constant of the first order reaction and levels of nitrogen and phosphorus at the anaerobic pond phase.From the equation, the optimized nitrogen and phosphorus level has been obtained 0 and 5.2 respectively.This result will be used to improve the pulp wastewater treatment in the stabilization pond of Huaxin Pulp and Paper Ltd.
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    STUDY ON OXYPOLYMERIZATION OF URUSHIOL CATALYZED BY POLYPHENOL OXIDASE
    LEI Fu-hou;LAN Hong-yun;AN Xin-nan
    2003, 23 (3):  53-55. 
    Abstract ( 625 )   PDF (361KB) ( 716 )   Save
    Oxypolymerization of urushiol in the air with polyphenol oxidase(PPO) as catalyst, acetone or dioxane as dissolvent was studied.The reaction system was determined by UV/VIS.Results showed three absorption peaks at 409, 490 and 653 nm respectively.The intensity of three absorption peaks changed when the reaction was catalyzed by PPO.Absorption peaks at 218 and 228 nm, from conjugates double bond and triene also changed.The reaction of urushiol catalyzed by PPO was similar to that of laccase .Probable mechanism of the reaction was put forward.
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    RESEARCH ON PREPARATION OF ACTIVATED CARBON FROM BAMBOO KNOT BY MICROWAVE RADIATION
    FAN Xi-an;PENG Jin-hui;QIN Wen-feng;GUO Sheng-hui;ZHANG Shi-min
    2003, 23 (3):  56-60. 
    Abstract ( 673 )   PDF (919KB) ( 754 )   Save
    Feasibility of activated carbon preparation from bamboo knot by microwave radiation was studied.Effects of microwave power, activation time, ZnCl2 solution concentration and flow rate of water vapor on the quality of activated carbon was investigated.The optimum technology of activated carbon preparation with water vapor activation by microwave radiation was obtained as follows:microwave power 700 W, activation time 7 min, flow rate of water vapor 3.1 mL/min.Activated carbon was prepared with iodine value 1012.2 mg/g, decoloring capacity for methylene blue 165 mL/g and yield 52.3%.Activation time was 1/45 and yield of activated carbon was twice as that of the conventional process respectively.The optimum technology of activated carbon preparation with ZnCl2 activation by microwave radiation was obtained as follows:microwave power 350 W, activation time 5 min, ZnCl2 solution mass parts 40%. Activated carbon was prepared with iodine value 1088.4 mg/g, decoloring capacity for methylene blue 220 mL/g and yield 39.2%.Activation time was 1/36 of the conventional process.The decoloring capacity for methylene blue was 1.83 times of that of the first grade product specified in the National Standard(GB/T 12496.10-1999).
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