Table of Content

30 June 2005, Volume 25 Issue 2 Previous Issue    Next Issue

研究报告

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RESEARCHES ON SYNTHESIS OF SQUALENE FROM FARNESYL BROMIDE AND MECHANISM OF ISOMER FORMATION SUN Zhen;ZHAO Zhen-dong;LI Dong-mei;LIU Xian-zhang 2005, 25 (2):  1-5.  Abstract ( 759 )   PDF (635KB) ( 665 )   Save Squalene was successfully synthesized from farnesyl bromide with the highly efficient reductive coupling reagent tri-triphenylphosphine cobalt chloride that was freshly prepared in the laboratory. Effects of main reaction conditions such as reaction time to the coupling reaction and the yield of squalene were studied primarily. The results showed that the yield of squalene was achieved at 45.6% under conditions of room temperature, extra 10% of the coupling agent, 4 h and efficient stirring. The product was analyzed by gas chromatography and GC-MS, and the possible formation mechanism and structures of the 6 isomers as well as their sequence in the chromatographic chart were predicted. In addition, the effects of the charging speed of NaBH4 and stirring condition to the reaction preparing the reagent were also studied. Related Articles | Metrics

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SYNTHESIS OF FUNCTIONAL POLYMER MATERIAL WITH POLYPHENOLIC ACID (I)—— Esterification of Gallic Acid with Cellulose and Functional Test of Product CHEN Jia-hong;WANG Yong-mei;WU Dong-mei;WU Zai-song;WANG Cheng-zhang 2005, 25 (2):  6-10.  Abstract ( 738 )   PDF (707KB) ( 1052 )   Save A new functional polymer material, namely galloylcellulose, was synthesized with gallic acid as functional group, and cellulose as molecular skeleton. Gallic acid was firstly acetylized with acetic anhydride to protect phenolic groups, then reacted with SOCl2 or PCl5 to prepare intermediate tricetyl-galloylchloride, in which the yields were 80% and 90% respectively. Taking pyridin as catalyst, the intermediate was esterified with cellulose. After deacetylating, the target product, galloylcellulose, was obtained with esterification ratio of 43.6%. Functional test results indicated that 1 g of galloylcellulose can adsorb 65.5 mg gelatin, or complex 76.5 mg Fe3+. The desorption ratio was about 98%. Galloylcellulose is reusable and stable in dilute acidic, ethanolic solutions and hot water. This study established groundwork for further developing commercial product of the new functional polymer material which can be used in brewing process to adsorb proteins and complex heavy metal ions. Related Articles | Metrics

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INVESTIGATION ON KINETICS OF BAMBOO PYROLYSIS CHEN Ji-zhong;DENG Tian-sheng;JIANG Bin-bo 2005, 25 (2):  11-15.  Abstract ( 686 )   PDF (1077KB) ( 876 )   Save The kinetics of bamboo pyrolysis is essential to understand carbonization of bamboo and effective utilization of bamboo. In this paper, the study on pyrolysis kinetics of bamboo was based on thermogravimetry. Outer, middle and inner parts of bamboo were pyrolyzed in TG equipment (TGA/SDTA851e) at heating rates of 5, 10, 20, 30 and 40℃/min under the temperature range of 40 - 500℃ and N2 atmosphere, respectively. TG results demonstrated that the pyrolysis process of bamboo may be considered as a two-step reaction, one corresponds to the decomposition of hemicellulose and the other to the decomposition of cellulose and lignin. The experimental data were treated by supposing the reaction order of bamboo pyrolysis to be 0.5, 1, 1.5 and 2, respectively. The appropriate reaction order of 1.5 or 2 was obtained by minimizing the difference between the calculated and measured data and the orders of pyrolysis reaction for different bamboo parts are the same at heating rate of 5 to 40℃/min. The results showed that the heating rate of pyrolysis process influences the order of pyrolysis reaction, activation energy and frequency factor. Related Articles | Metrics

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FT-IR SPECTROSCOPIC ANALYSIS ON WOOD CARBONIZATION MECHANISM JIANG Mao-sheng;HUANG Biao;CHEN Xue-rong;TANG Xing-ping 2005, 25 (2):  16-20.  Abstract ( 709 )   PDF (945KB) ( 1107 )   Save By FT-IR spectral study, an attempt has been made to investigate the variations of carbon net construction and main functional groups on the surface of carbonized material of Chinese fir wood in the process of carbonization. The results indicated that the variations of absorption intensity of three characteristic bands, 1600, 3100-3200 and 900-650 cm-1, and the shift of absorption peak of 1600 cm-1 can reflect the variations of aromatization degree and carbon net construction of the charcoal. With temperature rising, the degree of carbon polymerization is increasing, and the main functional groups on the charcoal surface are changed obviously. From 600-700℃, dehydration of the hydroxyls in carbonized material takes place abundantly, and the carbon net construction is developed highly. Furthermore, slow carbonization is beneficial to form better ordered carbon-net construction with less functional groups on the charcoal surface. Related Articles | Metrics

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THE INFLUENCING FACTORS AND KINETICS CHARACTER OF THE REDOX REACTION BETWEEN CATECHIN AND Cr6+ WANG Ying-hong;CHEN Wu-yong;HUANG Zan 2005, 25 (2):  21-24.  Abstract ( 717 )   PDF (711KB) ( 776 )   Save Plant polyphenol can be used as a reductant to prepare chrome tanning agents. The kinetic of the reaction between catechin, which is the procursor of condensed plant polyphenol, and dichromate plays an important role in the study of this preparation. The influencing factors and kinetics character of the redox reaction between catechin and dichromate under different conditions were investegated by spectrophotometry. The results show that redox reaction may be accomplished mostly in 1 min when the reaction begins. The influences of catechin concentration, solution acidity and reaction temperature on redox reaction rate were also investigated. The reaction rate equation at 25℃ was obtained. At temperature over 35℃, there may be multi-radicle reactions which may result in more complicated mechanism that happens between catechin and Cr6+ Related Articles | Metrics

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THE BEHAVIOR OF BIOMASS PYROLYSIS CATALYZED BY METALLIC IONS AND THEIR EFFECTS ON THE PRODUCTS LIAO Yan-fen;WANG Shu-rong;LUO Zhong-yang;CEN Ke-fa 2005, 25 (2):  25-30.  Abstract ( 603 )   PDF (737KB) ( 1072 )   Save Catalytic behavior and effects of K+ and Ca2+ in the process of cellulose pyrolysis were studied in an infrared radiation pyrolysis system. In the case of medium pyrolysis temperature, catalysis of potassium salt and calcium salt mainly occurred in solid phase, only few ions were released out of solid particles and entered into the liquid or gaseous products, which is beneficial for clean liquid fuel production from biomass. Both ions present the same catalysis behavior on biomass pyrolysis, as restrained formation of aqueous oil and enhanced production of char and gas. Besides, the quality of liquid product was improved by de-oxygen reaction catalyzed by K+ and Ca2+. In addition, K+ enhanced the cracking and disproportionating process of molecules to improve the production of hydroxyacetaldehyde, acetaldehyde and small-molecule components including groups of alcohols, ketones or aldehydes, while Ca2+ mainly influenced the rearrangement and isomerization of the monomeric sugar fragments to yield more furan and heterocyclic compounds. The selective catalysis behavior makes it possible to optimize biomass pyrolysis by selecting appropriate operation condition and metallic salts. Related Articles | Metrics

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STUDY ON RELATIONSHIP BETWEEN MOLECULAR WEIGHT OF SODIUM SULFATE-CELLULOSE AND ITS ANTICOAGULATION ACTIVITY WANG Zhao-mei;LI Lin;CHEN Ling;HE Chuan-bo 2005, 25 (2):  31-34.  Abstract ( 665 )   PDF (511KB) ( 692 )   Save Sodium sulfate-cellulose (Na-CS) had high anticoagulation activity. In order to study the relationship between the molecular weights ( Mw) and the anticoagulation activity of Na-CS, it was essential to prepare a series of Na-CS analogues having different Mw with the same sulfate substitution degree. In this study, Na-CS samples having different Mw were obtained by combinated separation method of acid hydrolysis and gel filtration-ion exchange. With these samples as objects of study, the effects of Mw on the anticoagulation efficacy of Na-CS and the inhibition of coagulation factors Ⅱa and Xa were studied. It was indicated that, with the increasing of Mw of Na-CS in a certain range, the prolongation on activated partial thrombo-plastin time (APTT) and thrombin time (TT) was increased and the inhibition on IIa and Xa was improved. Related Articles | Metrics

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DITERPENOIDS FROM TRIPTERYGIUM WILFORDII HOOK. F. CHEN Yu;YANG Guang-zhong;ZHAO Song;LI Yuan-chao 2005, 25 (2):  35-38.  Abstract ( 709 )   PDF (723KB) ( 763 )   Save To study the active principles in root core of Tripterygium wilfordii Hook. f., eleven diterpenoid compounds were isolated from this plant by silica gel column chromatography. Their structures were identified as triptoquinone A (1), hypoglic acid (2), triptoquine (3), isoneotriptophenolide (4), hypolide (5), triptonoterpene methyl ether (6), triptriolide (7), triptonide (8), triptolide (9), tripterfordin (10), 11-O- β-D -glucopyranosylneotritophenolide (11). Compound 11 is a novel compound. Related Articles | Metrics

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STUDY ON THE TECHNOLOGY OF MANUFACTURING GRANULAR ACTIVATED CARBON FROM SAWDUST FOR DECOLORIZATION OF LIQUID WANG Zhi-gao;JIANG Jian-chun;DENG Xian-lun;XU Yu 2005, 25 (2):  39-42.  Abstract ( 560 )   PDF (573KB) ( 887 )   Save Granular activated carbon for decolorization of liquid was made from sawdust by activation with H3PO4. The properties of the prepared product were as follows:methylene blue 155-170 mL/g; decolorization of caramel A ≥ 100%; ash ≤4%; abrasive resistance ≥ 95%; and the rate of mesopore 50%-65%. Moreover, the modeling mechanism during the preparing process was emphatically discussed to reach the following conclusion: the key point for improving abrasive resistance of granular activated carbon is to chose the suitable conditions of kneading and heat treatment. The product can be applied to the decolorization and refining of fermentation liquid in food and medicine industries. Related Articles | Metrics

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STUDY ON ACETYLATION OF LINALOOL CATALYZED BY NANO-SOLID SUPERACID SO42-/ZrO2 ZHANG Jia-yan;WU Chun-hua;ZHAO Qian-rong;AN Xin-nan;JIANG Jian-xin 2005, 25 (2):  43-46.  Abstract ( 740 )   PDF (553KB) ( 588 )   Save The acetylation of linalool catalyzed by nano-solid superacid SO42-/ ZrO2 was studied for the first time. Through individual factors experiments, the influences of reaction temperature, reaction time, dosage of catalyst and ratio between acetic anhydride and linalool on reaction had been discussed. By orthogonal test, the optimum technological condition had been obtained: the optimum temperature and time were 30℃ and 6.5 h, respectively, catalyst dosage was 2.5%,the ratio between acetic anhydride and linalool was 2.5:1 (mol ratio). Under the optimum condition,the conversion rate of linalool was 93.24%, the content of total ester was 76.89%, linalyl acetate content was 53.78% among products. Through comparison between the nano-solid superacid SO42-/ ZrO2 and other catalysts used to acetylizing linalool,the reaction time of the former was shorter, and the catalyst could be reused. This catalyst had good potential of application. Related Articles | Metrics

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AN INDUSTRIAL TEST ON CONTINUOUS CARBONIZATION OF BAMBOO IN MULTITUBULAR MOVING BED HU Fu-chang;CHEN Shun-wei;KANG Zhi-xiong;YANG Si-xin;ZHUANG Xiao-wei 2005, 25 (2):  47-51.  Abstract ( 722 )   PDF (637KB) ( 958 )   Save A type of stove which is suitable for continuous carbonization of bamboo was developed, and an industrial test at scale of 200 t annual production of bamboo char was carried out. The bamboo stalks were processed into bamboo slices of length 35 cm width 4-7 cm. The processed bamboo residue was broken into smaller pieces less than 10 cm. Raw materials were fed into the feed opening, to shift downward progressively by gravity,then subjected to drying, charring and calcination sequentially. After natural cooling, the char was discharged regularly. Gas rose along boiler tube, accompanied with distillation and heat transfer, then condensated into bamboo pyroligneous liquid. The result showed: yield of bamboo char was 24.7% of the dry bamboo timber; fixed carbon content above 94%, average absorbing value of iodine 700 mg/g, electrical resistance value generally under 10 Ω; yield of bamboo pyroligneous liquid was 20% of the dry bamboo timber, pH value at 2.4-2.8, the average content of total acid 5.07%, average soluble tar content 1.17%; average consumption of bamboo residue is 0.287 t per ton of bamboo char. Related Articles | Metrics

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STUDY ON PREPARATION OF XYLOSE FROM BAMBOO CHIPS CHANG Ya-ning;YAN Shu-wei;YU Jian-ying;WO Niao-ping 2005, 25 (2):  52-54.  Abstract ( 638 )   PDF (531KB) ( 763 )   Save This work deals with preparation of crude xylose by hydrolyzing bamboo chips, which is a novel raw material applied to xylose production. The preparation process consists of pretreatment, acid hydrolysis, neutralization, decoloration and concentration.The product xylose is identified by silica gel TLC, optical activity measurement and other approval tests. The yield of the obtained xylose is 80% of the theoretical amount. Related Articles | Metrics

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STUDY ON PREPARATION AND APPLICATION OF CATIONIC POLYMER POTENTIATING AGENT FOR PAPER SIZING CHU Fu-qiang;QIU Hua-yu;LI Jian-wen;CHEN Fu-shan 2005, 25 (2):  55-58.  Abstract ( 643 )   PDF (556KB) ( 848 )   Save The cationic polyacrylic ester emulsion (CPEE) was produced from methyl acrylate, styrene, cationic monomer and other chemicals by means of soap-free polymerization. The optimum condition of preparation was as follows cationic monomer and initiator were 5% and 1% in the total monomer respectively. CPEE, polyaminoamide-epichlorohydrin (PAE) and cationic starch (CS) were used as potentiating agent in the sizing of straw stock. With the help of the above polymers, cationic petroleum resin sizing agent could be used at neutral conditions to produce good sizing effect. Experimental result indicated that CPEE and PAE could apparently improve sizing degree and break length of paper sheet when used together properly. The above two polymers had better potentiation effect on sizing than ordinary retention aids commonly used in papermaking. Related Articles | Metrics

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EFFECTS OF MOLECULAR WEIGHT DISTRIBUTION OF XYLAN ON XYLANASE SYNTHESIS BY TRICHODERMA REESEI RUT C-30 MAO Lian-shan;YONG Qiang;YAO Chun-cai;YU Shi-yuan 2005, 25 (2):  59-62.  Abstract ( 604 )   PDF (505KB) ( 526 )   Save Effects of molecular weight distribution of xylan on xylanase synthesis by Trichoderma reesei Rut C-30 have been investigated. By Sephadex G-100 column chromatography, it was found that xylan A contained more low- molecular weight components, and xylan B contained less low-molecular weight components, while xylan C contained the least low-molecular weight components. These xylans were used as carbon source for xylanase synthesis,and presented the highest xylanase activity at 153.64, 120.84, 110.84 IU/mL,and culture time were 60, 72, 96 h, respectively. When xylan A was used as the carbon source for xylanase synthesis, xylo-oligosacchrides were 80.70% of the total sugars in the hydrolysate, which were increased by 17.71% and 20.59%,compared to that xylanases synthesized with xylans B and C. It indicated that the more the low-molecular weight components in xylan, the better the xylanases were induced, and the less the culture time was required to obtain high xylanase activity, and low- molecular weight components of xylan were favorable to inducing endo-1,4-β-D-xylanase. Related Articles | Metrics

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NEW METHOD FOR DETERMINING CONTENT OF RESVERATROL IN EXTRACT OF POLYGONUM CUSPIDATUM SIAB. ET ZUCC. BY SYNCHRONOUS FLUOROMETRY ZHANG Min;CAO Yong;YU Hua-zhong;GONG Zhu-qiong;LI Gui 2005, 25 (2):  63-66.  Abstract ( 638 )   PDF (635KB) ( 690 )   Save A new method was established to determine content of resveratrol in extract of Polygonum cuspidatum Siab. et Zucc. by sychronous fluorometry. Effects of fluoresence intensity, as well as its precision, repetition and recovery efficiency were studied systematically. The linear relationship was y = 18.90x + 3.1298,or fluorescence intensity of the system presented a linear relationship with concentration of resveratrol in the range of 0-1.68×10-5 mol/L, the detection limit was 8.839×10-10 mol/L.The study indicated that this method is simple, viable, of low cost and high precision. It could be used in both scientific research and industrial production. Related Articles | Metrics

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ISOLATION AND IDENTIFICATION OF CELLULOSE-DECOMPOSING MIXED STRAIN CAI Yan-fei;LI Hua-xing;PENG Gui-xiang;LIU Yuan-jin;CAI Ai-hua;ZHAO Su-qing 2005, 25 (2):  67-70.  Abstract ( 1204 )   PDF (891KB) ( 1089 )   Save A cellulose-decomposing mixed strain was isolated from natural habitats, which contained Klebsiella sp., Pseudomonas sp., Stenotrophomonas sp. identificated by 16S rDNA sequencing. By comparing the relative activity of carboxymethyl cellulose(CMC)enzyme and the effects on decomposing filter paper and banana plant stalks among each single bacteria and the mixed strain, it was shown that each strain had certain capability of decomposing cellulose, but mixed strain behaved the best and the relative activity of CMC enzyme was 0.93 cm/d. It indicated that synergistic effect among several microorganisms would accelerate the decomposition of cellulose materials. Related Articles | Metrics

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STUDY ON DECOLORIZATION CONDITIONS OF XYLITOL FERMENTATION BROTH FANG Xiang-nian;XIA Li-ming 2005, 25 (2):  71-74.  Abstract ( 666 )   PDF (562KB) ( 807 )   Save Two kinds of xylitol fermentation broths were decolorized using granular activated charcoal. The combinated effects of activated carbon dosage, initial pH value, contacting time, agitation speed, and temperature on the decolorization efficiency of xylitol fermentation broths were investigated. The best decolorization effect was found by adding 250 g activated carbon to 1.0 L fermented broth from hemicellulose hydrolysate (FBH) at 50℃ and pH value 6.0, stirring at 125 r/min for 20 min, and 150 g activated carbon to 1.0 L fermented broth from xylose synthetic medium (FBX) at 50℃ and pH value 6.0, stirring at 125 r/min for 20 min. When FBH was treated with activated carbon combinated with pH value adjustment and filtration of the precipitated pigment, the activated carbon dosage could be reduced by 50 g/L and the xylitol recovery rate could be increased by 6%. This work should be helpful to the development of a complete fermentation process for producing xylitol with high efficiency. Related Articles | Metrics

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STUDY ON COPOLYMER COATING OF TERPENE-CATECHOL WITH RAW LACQUER (II)——Study on Synthesis and Property of Copolymer Coating from Terpene-Catechol with Raw Lacquer LEI Fu-hou;LAN Hong-yun;YAO Xing-dong;MO Qun-ying;AN Xin-nan 2005, 25 (2):  75-79.  Abstract ( 595 )   PDF (756KB) ( 492 )   Save The synthesis of terpene-catechol resin from terpene resin and catechol and copolymer coating based on the produced resin with raw lacquer were reported in this paper. The synthetic conditions and properties of the copolymer coating were studied. The effects of ratio of terpene-catechol resin and raw lacquer, catalyst, reaction time and solvent on the film properties of coating were discussed. The reaction time was shorten 3 h, drying time was shorten 1 d at catalyst dosage 1%, and properties of the copolymer coating were improved. UV analysis of the coating showed that the reaction between terpene-catechol resin and raw lacquer was a copolymerization reaction. The optimum condition of painted film was that terpene-catechol resin and raw lacquer(1:4) reacted for 5.5 h with catalyst(1%) in petrol solvent. Drying time of the film was 3 d after the coating was painted. Related Articles | Metrics

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SEPARATION,PURIFICATION AND STRUCTURAL STUDIES OF POLYSACCHARIDES FROM POLYGONATUM KINGIANUM WU Qun-rong;HU Sheng;YANG Guang-zhong;MEI Zhi-nan 2005, 25 (2):  80-82.  Abstract ( 726 )   PDF (666KB) ( 899 )   Save Three polysaccharide components were isolated from Polygonatum kingianum Coll.et Hemsl, by hot water extraction,ethanol precipitation,and purification through DEAE-cellulose and gel permeation column chromatography. The structural feature of P. kingianum polysaccharide I (PKP I) was identified by chemical (including sugar composition analysis, methylation analysis and periodate oxidation) and spectral analyses (IR, 1H NMR and GC-MS). The results showed that PKP I was mainly composed of glucose, the main chain of polysaccharide was α -(1→ 4) linked, and mean molecular weight was 8100. Related Articles | Metrics

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STUDY ON SUPERCRITICAL CARBON DIOXIDE EXTRACTION OF VOLATILE OIL FROM ZANTHOXYLUM BUNGEANUM MAXIM. CV. DAHONGPAO AND ITS CHEMICAL COMPONENTS GONG Zhu-nan;MI Xiang-hui;LIANG Qiao-li;LIAO Xue-wei;ZHANG Wei-ming 2005, 25 (2):  83-86.  Abstract ( 675 )   PDF (753KB) ( 855 )   Save The volatile oil from Zanthoxylum bungeanum Maxim. cv. Dahongpao has been associated with various pharmacological activities. A systematic method was used to optimize the supercritical carboon dioxide extraction (SCDE) of the volatile oil. Overall 3 variables (pressure, temperature, extracting time) were considered. The optimized conditions were: temperature 55℃, pressure 33 MPa, time 60 min. Thirty one chemical components of the volatile oil were determined qualitatively and quantitatively by GC-MS. Among them the content of 3 methyl-2- ozafluorene is the highest, about 18.63%. Related Articles | Metrics

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FUNCTION OF ENDOGLUCANASE I IN THE DEINKING PROCESS OF MIXED OFFICE WASTE PAPER WU Shu-fang;DING Shao-jun;LI Zhong-zheng 2005, 25 (2):  87-90.  Abstract ( 605 )   PDF (703KB) ( 645 )   Save The performance of endoglucanase I (EG Ι) was investigated in the deinking process of mixed office waste paper(MOW). Results showed the optimal treatment conditions of temperature 60℃,pH value 7.5, treated time 40 min and enzyme dosage 0.5 IU per gram pulp. Though enzymic treatment decreased the degree of polymerization(DP) of pulp, the DP decreased limitedly within definite enzyme dosage. EG Ι played an important role in the deinking process of MOW because the improvement of ink-removal in floated pulp after EG Ι treatment was achieved. Meantime the existence of ash in waste paper with fillers or coating (consisted mainly of CaCO3) affected deinking efficiency. An acid treatment could enhance deinking efficiency and further improved the deinking effectiveness of EG Ι. Related Articles | Metrics

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STUDY ON INTERPENETRATED POLYMER NETWORK COATING OF URUSHIOL-FERRIC POLYMER AND ALKYD RESIN LIU Jian-gui;LIN Jin-huo;CHEN Qin-hui;XU Yan-lian;XIAO Peng 2005, 25 (2):  91-94.  Abstract ( 503 )   PDF (715KB) ( 569 )   Save Interpenetrated polymer network (IPN) coating was prepared from urushiol-ferric polymer(PUF) and multihydroxyl alkyd resin (AlR). Its structure, mechanism of network formation and behavior of mechanical properties were characterized by DMTA, IR and other physico-chemical means. The solvent resistance and dynamic mechanical properties were also studied. The results showed that IPN was formed at definite ratio of PUF and AlR, with the combinated features of PUF coating and acrylic coating, especially its alkali resistance and solvent resistance were greatly improved. Related Articles | Metrics

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RELATIONSHIPS BETWEEN COMPOSITION AND PERFORMANCE OF WAX-ROSIN EMULSION AS WATER-REPELLENT OF FIBREBOARD WU Zong-hua;CHEN Shao-ping;SUN Xiu-wu;LI Ai-min 2005, 25 (2):  95-98.  Abstract ( 620 )   PDF (713KB) ( 1099 )   Save Series of wax-rosin emulsion were prepared using polymeric surfactants designed for the emulsion, and the effects of structure of the surfactant and the mass ratio of wax and rosin on the properties of the emulsion were investigated. The results showed that stable wax-rosin emulsion could be prepared using mixture of polymeric surfactant and the low molecular surfactants(LS) of derivative of alkylbenzyl polyoxyethyene ether. The polymeric surfactant (HS) was made from styrene, acrylic acid and its derivative. The use of emulsion at the mass ratio 1:2 of wax and rosin could reduce the adsorbing-water expansion coefficient of fibreboard by 23.8% and increase the modulus of elasticity by 12.2% at dosage of 5 kg/m3. The composition of the surfactant and the mass ratios of wax and rosin influenced significantly the properties and performance of the wax-rosin emulsion. Related Articles | Metrics

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CHEMICAL COMPOSITION OF THE ESSENTIAL OIL FROM PAULOWNIA TOMENTOSA FLOWERS WANG Xiao;CHENG Chuan-ge;LIU Jian-hua;ZHENG Cheng-chao 2005, 25 (2):  99-102.  Abstract ( 944 )   PDF (437KB) ( 831 )   Save The essential oil from the flowers of Paulownia tomentosa (Thunb.) Steud. was obtained through hydrodistillation. The chemical components were separated and identified by GC-MS. Relative content of each component was determined by area nomalization. Sixty-nine compounds representing 89.33% of the oil were identified. The most abundant constituents were benzyl alcohol (13.276%), 1,2,4-trimethoxybenzene (8.342%), phenol,2-methoxy-3-(2-propenyl)(6.141%), phenol,3,4-dimethoxy-( 3.986% ), tricosane(3.682%) and pentacosane (3.238%). Related Articles | Metrics

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DETERMINATION OF FORMALDEHYDE CONTENT IN THE AMINOMETHYLATED PRODUCT OF TANNIN BY POTENTIOMETRIC TITRATION FANG Gui-zhen;WU Chen-liang 2005, 25 (2):  103-106.  Abstract ( 639 )   PDF (574KB) ( 578 )   Save In this paper a potentiometric titration was used to improve the neutral sodium sulfite method for determining the content of formaldehyde, and the accuracy and influential factors were discussed. The results of quantitative determination of formaldehyde in the aminomethylated product of tannin showed that the mensurative rate of formaldehyde in reaction system was 93.82%, r =0.999, the recovery rate of the blank test was 97.74%, r = 0.999, temperature was controlled at 15-20℃, laying time was between 1 h for stabilization. This method eliminated the defects of coloured and cloudy liquor which blurred the end point of titration by indicator. The range of electric potential was wide, the repetition and accuracy of data were perfect. This method is quick, simple and easy to control. Related Articles | Metrics

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CONSTITUTION OF VOLATILE OILS FROM THREE KINDS OF PTERIDOPHYTE PLANTS CHENG Cun-gui;MAO Jiao-yan 2005, 25 (2):  107-110.  Abstract ( 783 )   PDF (451KB) ( 758 )   Save Volatile oils from pteridophyte plants, namely Selaginella moellendorfii Hieron, Lygodium japonicum (Thunb.)Sw. and Pterismultifida Poir., were obtained by hydrodistillation. The oils obtained were analyzed by GC-MS. More than 90,38 and 57 peaks were separated respectively,and 86,36 and 55 compounds representing 95.56%,94.74% and 96.49% of the oils respectively were identified which indicated that there were 16 kinds of identical substances in the oils. Essential oil constituents from S. moellendorfii, L. japonicum and Pterismultifida were mainly higher alkanes, alkenes, alcohols, phenols and aldehydes. Related Articles | Metrics

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STUDY ON OPTIMUM PROCESS FOR EXTRACTING CAPSAICIN IN PAPRIKA( CAPSICUM ANNUUM L.) BY ORTHOGONAL TEST GAO Yi;ZHOU Chun-shan;JIANG Xin-yu;CHEN Long-sheng;CHEN Yan 2005, 25 (2):  111-114.  Abstract ( 624 )   PDF (723KB) ( 933 )   Save The optimum process of extracting capsaicin,the bioactive component in paprika( Capsicum annuum L.) was studied.The optimum extraction process was optimized with orthogonal test.Experiments were made by using L9(34) orthogonal design with extractive yield of capsaicin as the index,investigating the influence of ethanol concentration,temperature,extracting time and the ratio of solid to liquid.Optimum extraction conditions were determined as follows:temperature 70℃,time 0.5 h,70% EtOH as extracting solvent,stock ratio 1:10(mass:volume),extracting for three times. Related Articles | Metrics

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STUDY ON VAPOR-PHASE BORATE PRESERVATIVE TREATMENT OF WOOD JIANG Ping;JIN Zhong-wei 2005, 25 (2):  115-118.  Abstract ( 629 )   PDF (635KB) ( 561 )   Save Studies on vapor-phase borate preservative treatment of Masson pine ( Pinus massoniana ) and Douglas fir[Pseudotsuga menziesii (Mirbel) Franco]wood samples had been carried out.The optimum preservative treatment conditions were investigated by using orthogonal experiment as follows: wood sample moisture content 10%, preservative treatment temperature 75℃, reduced-pressure treatment 97.325 kPa, preservative temperature 32℃. Boric acid content of Masson pine sample was 6.13%. Test results of vapor-phase borate preservative treatment on Douglas fir heartwood samples that can hardly be treated indicated: permeability was good. Using electronic microscopy,it was found that boric acid was deposited in both samples by vapor-phase treatment and by liquid treatment. However, boric acid content of samples of the former was higher than that of the later in wood cells. Testing results on mechanical properties and dimensional change of Masson pine samples indicated that impact strength and modulus of elasticity of the treated wood decreased insignificantly. Bending strength of the treated wood was elevated by 4.6%. Dimensions of wood samples changed very small. Related Articles | Metrics

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CHEMICAL CONSTITUENTS OF VOLATILE OIL FROM PODOCARPUS FLEURYI HICKEL HE Dao-hang;PANG Yi;REN San-xiang;LI Guang-hong;SONG Shao-yun 2005, 25 (2):  119-121.  Abstract ( 703 )   PDF (630KB) ( 715 )   Save From hydrodistillation, 0.5% of an volatile oil on a fresh weight basis was obtained from leaves of Podocarpus fleuryi Hickel. Twenty-four constituents were identified by GC-MS analyses for the first time. The identified constituents represent 97.29% of the peak area of the oil. Terpenes and alcohols are major chemical constituents in the oil. The main compounds were α -pinene (8.67%), (-)- β -elemene (2.68%), β -caryophyllene (3.97%), (+)-ledene (2.11%), germacrene D (21.56%), o -menth-8-ene,4-isopropylidene-1-vinyl-(45.13%), β -cadinene (2.02%) and (-)-spathulenol (3.15%). Related Articles | Metrics

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COMPREHENSIVE UTILIZATION OF TAMARINDUS INDICA LINN. ZHAO Yi-he;YANG Shi-yu;LI Kun 2005, 25 (2):  122-126.  Abstract ( 659 )   PDF (479KB) ( 1280 )   Save Tamarind ( Tamarindus indica Linn.) fruits can be widely used as fruit, medicine, beverage or food. The extract of tamarind seed contains polysaccharide and antioxidative components. The tree can be used for landscape afforestation. The status of comprehensive utilizations of tamarind at home and abroad during the recent twenty years were reviewed, which pointed out that its utilizations are focused on processing and utilization of tamarind fruit flesh and extract of tamarind seed polysaccharide (TSP). Some proposals on future exploitation were put forward according to the existing problems in the utilization of tamarind. Further utilizations of the plant are also involved in this article. Related Articles | Metrics