Table of Content

30 December 2010, Volume 30 Issue 6 Previous Issue    Next Issue

研究报告

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Preparation and Properties of Thermoplastic Acorn-starch LI Shou-hai;ZHUANG Xiao-wei;WANG Chun-peng;CHU Fu-xiang 2010, 30 (6):  17-23.  Abstract ( 705 )   PDF (1492KB) ( 656 )   Save Thermoplastic acorn-starch (TPAS) was produced by blending acorn-starch and plasticizer with a twin-screw extruder.The effects of different plasticizers such as glycol, glycerol, monoethanolamine, diethanolamine and triethanolamine on mechanical,thermal and hydrophobic properties of blended composites were studied by tensile test analysis, water absorption analysis, moisture absorption analysis, X-ray diffraction(XRD)analysis, scanning electron microscopy(SEM)analysis, dynamic mechanical thermal analysis(DMA)and thermogravimetric analysis(TGA).The results demonstrated that TPAS materials showed strong water and moisture absorption properties. The mechanical properties of TPAS materials varied with different type of plasticizer, content of plasticizer and moisture absorption of TPAS. The results showed that these 5 plasticizers had good performance for plasticizing acorn starch by SEM and XRD analysis. The native acorn starch granules were proved to be transformed into a homogeneous continuous phase through the transformation of all crystalline structure. DMA and TGA results showed that the plasticized effect and thermal stability of TPAS materials also varied in different plasticized systems. Related Articles | Metrics

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Galloylation of Procyanidin from Larch Bark and Its Enhancement Effects on Antioxidant Activity XU Man;CHEN Jia-hong;WANG Yong-mei;WU Dong-mei;WU Zai-song;ZHANG Liang-liang; 2010, 30 (6):  55-60.  Abstract ( 742 )   PDF (1099KB) ( 722 )   Save Galloylation of procyanidin was carried out using procyanidins(PC) separated from larch bark as raw material. Galloyl groups were inserted into procyanidin molecule based on esterification, and galloylated procyanidins(GPC)were obtained consequently. It was showed that galloylation had taken place and number of hydroxyls in molecule had increased from FT-IR spectra of PC and its galloylated product. Through estimation of gallic acid quantity in product hydrolysate by HPLC method, the galloylation degree was 63%. Furthermore the researches on biological activity difference between PC and GPC were carried out through estimation of radical-scavenging activity and complexation ability for transition metal ions, as well as antioxidation ability toward fat, showing that the biological activity of procyanidin after galloylation was enhanced observably. Related Articles | Metrics

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Study on Preparing Phenylpropyl Aldehyde from Cinnamon Oil by Direct Hydrogenation HE Jun-lin;WANG Jian-ping;LI Ning;HE Li-ping;CHEN Yue-xin;WEI Bing-qian;ZHANG Chao-hui 2010, 30 (6):  71-76.  Abstract ( 627 )   PDF (2284KB) ( 584 )   Save Direct hydrogenation of cinnamon oil to prepare phenylpropyl aldehyde was studied. The hydrogenation experiments were carried out in the 2 L and 1 m3 reactors respectively.The results showed that the best conditions were as follows:3% mass fraction of Raney-Ni 2# as catalyst,reaction temperature 50℃,reaction pressure 4.0 MPa,time 4.0 h. Under these conditions,mass fraction of the obtained phenylpropyl aldehyde reached 97.74%,and the yield reached 62.24%. Related Articles | Metrics

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Thermo-gravimetric Analysis on the Leaves of 16 Hardwood Species in Kunming Area GE Wei-wei;ZHANG Hong-yu;TANG Chao-gang;LI Shi-you 2010, 30 (6):  77-81.  Abstract ( 578 )   PDF (1020KB) ( 659 )   Save Thermo-gravimetric analysis was used to study the leaves of 16 species of hardwoods collected in Kunming area. The result showed that the pyrolysis process of leaves included three stages, namely drying, fast-pyrolysis and carbonization. The weight loss during the fast-pyrolysis stage was about 65%. The fast-pyroysis process could be described by the first-order model and Coats-Redfern method. Fireproof properties of Lithoca mairei and Ternstroemia gymnanther leaves are greater than other hardwood leaves. Their kindling point, activation energy and buring characteristics index were 282.7℃, 43.1 kJ/mol, 0.764×10-6 and 264.6℃, 41.4 kJ/mol, 0.635 1×10-6, respectively. Related Articles | Metrics

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Studies on Steam Explosion of Corncob and Its Optimization by Response Surface Methodology XU Bing-lei;PENG Qi-jun 2010, 30 (6):  82-88.  Abstract ( 742 )   PDF (1522KB) ( 858 )   Save The effects of steam explosion pressure and applied-pressure time on the degradation rate of hemi-cellulose, cellulose and lignin in corncob were studied by response surface methodology.Three model equations for steam explosion pressure and applied-pressure time on the degradation rate were built.Based on the three models and SAS 9.0 statistical software,the basic areas of cellulose without degradation were defined: to be under steam explosion pressure <1.946 MPa and applied-pressure time <155.7 s; and within this range, the condition for the greatest degradation rate of hemi-cellulose was found to be under steam explosion pressure 1.6 MPa, and applied-pressure time 113 s. Under this condition, the degradation rate of hemi-cellulose was 44.8% with total sugar yield 42.3%, reducing sugar yield 9.5%, xylan yield 39.4%, average degree of polymerization of xylan 4.5, simple sugar yield 1.9%(mainly xylose), and the degradation rate of lignin was 18.7%. The result is in good agreement with the model prediction, indicating that the model is reasonable and effective. Related Articles | Metrics

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Study on Synthesis of 1-(3,4,5-Trimethoxy-benzoyl)-benzotriazole JIANG Ping;MI Wei;LI Hai-yu 2010, 30 (6):  89-92.  Abstract ( 676 )   PDF (628KB) ( 566 )   Save 1-(3,4,5-Trimethoxy-benzoyl)-benzotriazole was synthesized from chlorinated 3,4,5-trimethoxy benzoic acid and benzotriazole. The synthesis process was optimized. The results showed that using dichloromethane as solvent, triethylamine as catalyst, molar ratio of benzotriazole, 3,4,5-trimethoxybenzoyl chloride and triethylamine 1:1:1.2, added at 0℃, reaction 3 h under 20℃, the yield can reach 99%。 Related Articles | Metrics

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Study on Double Enzymatic Hydrolysis of Acorn Starch Optimized by Factorial Design CHENG He-fang;WEI Min;JIANG Jian-chun;ZHANG Ning 2010, 30 (6):  93-96.  Abstract ( 681 )   PDF (788KB) ( 661 )   Save Effects of double enzymatic hydrolysis of acorn starch were studied by factorial design. The main factors, namely amylase dosage, liquefaction time, glucoamylase dosage and saccharification time were optimized by orthogonal tests. Through analysis, the optimal conditions were obtained as follows: amylase dosage 50 U/g, liquefaction time 2 h, saccharification time 2 h, and glucoamylase dosage 600 U/g. Under these conditions the dextrose equivalent value(DE) of the acorn liquefied solution was 58.15%. Related Articles | Metrics

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Simultaneous Separation of Solanesol and Coenzyme Q10 from Tobacco(Nicotiana tabacum L.)Extract Using Supercritical Carbon Dioxide LI Chun-ying;ZHAO Chun-jian;ZU Yuan-gang;WANG Lei 2010, 30 (6):  1-6.  Abstract ( 721 )   PDF (663KB) ( 607 )   Save A method for simultaneous separation of solanesol and coenzyme Q10 from tobacco (Nicotiana tabacum L.) extract using supercritical carbon dioxide (SC-CO2) was developed. The effects of extraction time, pressure, temperature and CO2 flow rate on yield of solanesol and coenzyme Q10 were studied. The optimum conditions are met for extraction time 60 min, pressure 36 MPa, temperature 59℃ and CO2 rate of 10 kg/h. Under the optimized SC-CO2 separation, the extraction yields of solanesol and coenzyme Q10 are 1.84% and 2.07 mg/g, respectively. The contents of solanesol and coenzyme Q10 in the extract obtained by optimized SC-CO2 are 52.3% and 3.6%, respectively. Related Articles | Metrics

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Study on Novel Technology of Preparing Activated Carbon from the Waste of Furfural Manufacture by Corncob Hydrolysis GONG Jian-ping;DENG Xian-lun;ZHU Guang-zhen;ZHANG Yan-ping 2010, 30 (6):  97-101.  Abstract ( 567 )   PDF (870KB) ( 757 )   Save Using the waste of furfural manufacture by corncob acid hydrolysis as raw material, activated carbon was prepared by the combination of physical activation and chemical activation, and the comparison experiments for different process conditions were made. The experimental results show that activated carbon with preferable quality can be produced by adding 2% ash-fluxing agent into the raw material, subsequently activated by steam at 900℃, then washed by 15% HCl, thus ash content was decreased greatly. Methylene blue adsorption value of the product can reach 180 mg/g with ash content 6% and iron mass fraction 0.08%. Related Articles | Metrics

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Ultrasound-assisted Extraction of Flavonoids from Leaves of Lindera aggregata(Sims.)Kosterm CHEN Jian-jun;HE Guo-qing 2010, 30 (6):  102-106.  Abstract ( 464 )   PDF (781KB) ( 610 )   Save Ultrasound-assisted extraction of flavonoids in leaves of Lindera aggregata(Sims.)Kosterm(FL) was optimized by an uniform design experiment. The effects of ethanol volume fraction, ratio of liquid to solid, ultrasound power and ultrasound treatment time on the extraction yield of FL were investigated. The optimized ultrasound-assisted extraction was determined as follows:5 g leaves of FL, ultrasound treatment time 18 min,ultrasound power 250 W,ethanol volume fraction 40%,ratio of liquid to solid 10:1(mL:g). Under these conditions, the extraction yield of FL reached 2.13%. Mathematical simulation values based on ultrasound-assisted extraction was consistent with experimental values. Related Articles | Metrics

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Quantitative Determination of Functional Groups in Theabrownine from Pu-erh Tea Based on BaCl2 and Ca(CH3COO)2 Precipitation Methods QIN Yi;GONG Jia-shun;ZHANG Hui-fen;ZHOU Hong-jie;HE Jing;LI Bao-cai 2010, 30 (6):  107-112.  Abstract ( 747 )   PDF (1283KB) ( 684 )   Save The functional groups analysis methods,namely barium chloride (BaCl2) method and calcium acetate (Ca(CH3COO)2) method, were used to determine the content of functional groups of theabrownine for the first time, and suitable operating methods were established to determine the contents of total acidic groups, carboxyl groups and phenolic hydroxyl groups. The optimum conditions of determination were obtained as follows: for the BaCl2 method, sample weight 0.02-0.08 g, precipitation time 30-60 min, concentration of BaCl2 0.75 mol/L;for the Ca(CH3COO)2 method, sample weight 0.05-0.1 g, precipitation time 20 min, concentration of Ca(CH3COO)2 1 mol/L. The total acidic groups content of theabrownine from Pu-erh tea is 7.780 mmol/g, of which phenolic hydroxyl groups is 5.805 mmol/g and carboxyl groups is 1.975 mmol/g. The results indicate that phenol hydroxyl groups are the most important acidic groups in theabrownine. Both BaCl2 method and Ca(CH3COO)2 method are simple and require neither elaborate equipment nor special skills. With satisfactory results, these methods appear to be suitable for use in the routine analysis of functional groups in theabrownine. Related Articles | Metrics

综述评论

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Research Progress on Production and Application of Xylitol LIU Chun;FANG Gui-gan;SHI Ying-qiao;DENG Yong-jun;YIN Yan-fei 2010, 30 (6):  113-118.  Abstract ( 625 )   PDF (1320KB) ( 951 )   Save As an important chemical product, xylitol has a high application value. Based on recent development, three kinds of production methods were summarized in this paper, which were extraction method, chemical synthesis method and biological method. The advantages and disadvantages of three methods were also mentioned. The application of xylitol in food, medicine and chemical industry were summarized. Finally the future development trend of xylitol was discussed. Related Articles | Metrics

研究报告

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Effects of Lignin on Crystallization of Calcium Carbonate ZHU Wen-kun;;LUO Xue-gang;HE Pan;LU Yan 2010, 30 (6):  7-12.  Abstract ( 890 )   PDF (2876KB) ( 619 )   Save Based on the basic principles of biomineralization, the effects of lignin concentration and system temperature on the growth of CaCO3 crystals were studied. Moreover, the structure, appearance and thermal decomposition properties of CaCO3 were characterized by FT-IR, SEM, XRD and TG. The results demonstrated that CaCO3 formed in lignin solution was calcite, displaying dumbbell-shaped, spherical, oval or football-shaped appearance, which was different from that formed in pure water. Lignin concentration and system temperature had significant impact on the crystal morphology. During the course of crystallization, CaCO3 and lignin had mutual interaction, and the possible mechanism had been discussed. Related Articles | Metrics

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Study on Preparation of Acidic Granular Activated Carbon by Air-phosphoric Acid Activation of Charcoal ZUO Song-lin;MORITA Mitsuhiro 2010, 30 (6):  13-16.  Abstract ( 1017 )   PDF (617KB) ( 803 )   Save A novel activation method, namely air-phosphoric acid activation, was proposed for preparing acidic granular activated carbon from charcoal at temperatures of more than 800℃. Pore structures of activated carbons were analyzed based on the adsorption isotherms of nitrogen and carbon dioxide, and concentrations of surface functional groups were measured by Boehm method. The results indicate that air-phosphoric acid activation involves the effects of both air activation and phosphoric acid activation. In the process of air-phosphoric activation, air activation produced mainly mesopores while phosphoric acid produced mainly micropores. Phosphorus surface functional groups with strong acidity can be formed in activated carbon. Moreover, pore structure and surface chemistry of activated carbon can be regulated by changing the impregnating concentration of phosphoric acid and activation temperature. Related Articles | Metrics

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Pyrolysis Kinetics of Alkali Lignin Catalyzed by Sodium Carbonate YE Jie-wang;JIN Chun-de;SONG Ping-an;WU Qiang 2010, 30 (6):  40-44.  Abstract ( 813 )   PDF (873KB) ( 746 )   Save Influence of sodium carbonate (Na2CO3) on pyrolysis characteristics and kinetics of alkali lignin were studied by thermo-gravimetric (TG) analysis. Result show that depolymerization or glass transformation of alkali lignin are effected by Na2CO3, moving TG curve towards lower temperature. Na2CO3 has a promoting effect on the formation of char. Derivative thermogravimetry (DTG) curves of alkali lignin change from the original single peak to double peak. Coats-Redfern method was used to analyze the pyrolysis process and dynamics simulation was carried out. The pyrolysis of alkali lignin is a two-consecutive step first-order reaction, and the turning point of which moves towards lower temperature area. At lower temperature area, Na2CO3 shows a promoting effect on pyrolysis of alkali lignin, while an inhibitory effect at higher temperature area. Activation energy of main pyrolysis area of alkali lignin decreases after adding Na2CO3, indicating Na2CO3 to be benefitial for the pyrolysis of alkali lignin. Related Articles | Metrics

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Comparative Study on Chemical Components of Essential Oils from Pinus massoniana, P.sylvestris var.mongolica and Abies nephrolepis Needles BO Cai-ying;ZHENG Guang-yao;SONG Qiang 2010, 30 (6):  45-50.  Abstract ( 748 )   PDF (1039KB) ( 799 )   Save The GC-MS technique was applied to analyze the essential oil extracted by hydrodistillation from Pinus massoniana Lamb., P.sylvestris var. mongolica Litvin. and Abies nephrolepis(Trautv.)Maxim needles. The results showed that the essential oil yields of P.massoniana, P.sylvestris and A.nephrolepis were 0.50%, 0.43%, 0.48% respectively. Forty-six components in the essential oil from P.massoniana needles were identified, representing 99.24% of the TIC peak area. The main components are α-pinene (16.30%), β-caryophyllene (14.65%), β-pinene (9.38%), etc. Thirty-seven components in the essential oil from P.sylvestris needles were identified, representing 99.08% of the TIC peak area. The main components are δ-cadinene (18.55%), α-cadinol (10.23%), τ-muurolol (9.84%), etc. Forty-eight components in the essential oil from A.nephrolepis needles were identified, representing 99.73% of the TIC peak area. The main components are bornyl acetate (19.16%), α-limonene (14.93%), alcanfor (10.73%), etc. The contents of monoterpenes in the essential oil from P.massoniana are 43.80%, sesquiterpenes are 50.21%, and diterpenes are 4.63%. The contents of monoterpenes in the essential oil from P.sylvestris are 12.72%, sesquiterpenes are 84.73%, and diterpenes are 0.25%. The contents of monoterpenes in the essential oil from A.nephrolepis are 75.59%, sesquiterpenes are 20.46%, and diterpenes are 1.72%. The essential oil yeilds of the 3 spcies were similar but their chemical components and contents differed greatly, which might be resulted from the factors of species, age and growth environment. Related Articles | Metrics

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Preparation of SO42-/Fe2O3-Al2O3-SiO2 Solid Superacid Catalyst for Producing Levulinic Acid from Hydrolysis of Sucrose JIANG Hua-chang;ZENG Ling;YIN Bing-long;GAN Jun-jiang;LIU Bao-jian 2010, 30 (6):  61-65.  Abstract ( 760 )   PDF (946KB) ( 5986 )   Save SO42-/Fe2O3-Al2O3-SiO2 solid superacids of different proportions were prepared by co-deposition method and used for the reacion of catalytic hydrolysis of sucrose to produce levulinic acid. The results showed that calcination time and the dipping concentration of sulfuric acid affected the property of these catalysts. Calcination time and temperature affected surface area seriously. The shorter the calcination time and lower the calcination temperature, the larger was the specific surface area. The impregnation concentration by H2SO4 and impregnation time also impact the catalyst properties. The solid superacids were used for the catalytic hydrolysis of sucrose to produce levulinic acid. The improved activity was obtained under following conditions: calcination temperature 600℃, calcination time 4 h. The high yield of levulinic acid was obtained 33.05%. Related Articles | Metrics

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Isolation and Characterization of Water-soluble and Alkali-soluble Hemicelluloses from Wheat Straw WEI Wei-qi;WU Shu-bin;PENG Yun-yun 2010, 30 (6):  66-70.  Abstract ( 671 )   PDF (1044KB) ( 735 )   Save The structural characteristics of wheat straw hemicelluloses isolated from water and alkali were investigated by FT-IR,GPC,ion chromatographys,TGA and NMR. The results show that wheat straw hemicellulose is composed mainly of L-arabino-D-xylans with minor quantities of galactose,glucose,glucuronic acid and glacuronic acid,which is a typical structure of straw hemicellulose.Under the 20℃/min heating rate,the mass loss of two wheat straw hemicelluloses mainly happened between 200 and 330℃,the maximum weight loss rate occurred at 282 and 313℃ respectively, the thermal stability of alkali-soluble preparation is slightly higher than that of water-soluble preparation.The result of GPC revealed that water-soluble preparation is the hemicellose with high substitution degree of side chain and relatively low molecular weight, while alkali-soluble preparation is just on the opposite. Related Articles | Metrics

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Optimization of Decoloration in the Purification Process of Polyprenols from Ginkgo biloba L.Leaves YANG Lan;WANG Cheng-zhang;YE Jian-zhong;CHEN Hong-xia 2010, 30 (6):  51-54.  Abstract ( 547 )   PDF (663KB) ( 683 )   Save Mixture of activated carbon and attapulgite was first applied to the purification of polyprenols from Ginkgo biloba L.leaves using decoloration technology. Orthogonal experiment was designed to obtain the optimum conditions for decoloration and they were determined as follows: 10 g of crude polyprenols were dissolved in 100 mL petroleum ether, dosage of decolorant 12 g, mass ratio of activated carbon to attapulgite 1:5(g:g), temperature 70℃, time 20 min. The purity was increased from 38.58% to 49.6% after decoloration without loss of polyprenols. Related Articles | Metrics

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Effect of Activated Carbon Surface Area, Pore Size on Photocatalytic Activity of TiO2/AC LU Xin-cheng;JIANG Jian-chun;SUN Kang;CUI Dan-dan 2010, 30 (6):  29-34.  Abstract ( 670 )   PDF (1283KB) ( 736 )   Save Using a series of coconut activated carbon (AC) with different pore size and surface area as carriers, TiO2/AC immobilized photocatalysts were prepared through sol-gel method. Nitrogen adsorption, XRD, SEM were used to characterize the composite catalysts and study their photocatalytic activity. The results show that: activated carbon with large surface area and abundant medium pores is more suitable for TiO2 loading, and the obtained photocatalyst can win better photocatalytic activity and delayed inactivation time. The maximum degradation rate for toluene is up to 97%, deactivation time extends to 11 h, and suitable filling quantity helps to improve photo-degradation effect. Related Articles | Metrics

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Study on Liquefaction of Eucalyptus Wood Powder in Polyhydric Alcohol Catalyzed by Organic Sulfonic Acid ZHANG Hai-rong;JI Hong-guo;SHI Jin-zhi;FU Tie-zhu;PANG Hao;LIAO Bing 2010, 30 (6):  35-39.  Abstract ( 898 )   PDF (867KB) ( 712 )   Save Liquefaction of wood was conducted in polyhydric alcohol catalyzed by p-toluene sulfonic acid under different reaction conditions. The liquefied products were analyzed to understand the change of its properties and components during liquefaction process. When liquid to solid mass ratio was 4:1 and p-toluene sulfonic acid was 3%, liquefaction yield was 89.97% at 160℃ after 180 min. When the time was prolonged, hydroxyl value of the liquefied product decreased gradually from 460 to 340 mg/g, and acid value increased gradually from 13 to 20 mg/g. In addition, the real-time IR was used to detect the reaction during the whole experiment. Related Articles | Metrics

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Preparation of Activated Carbon from Camellia oleifera Shell and Its Mesoporous Structure Modification SUN Kang;JIANG Jian-chun;HE Yue;LIN Yu-suo;CUI Dan-dan;LU Xin-cheng 2010, 30 (6):  24-28.  Abstract ( 686 )   PDF (941KB) ( 808 )   Save Activated carbons from Camellia oleifera shell were prepared by steam activation and phosphoric acid re-activation to modify and enrich mesoporous structure. Results showed that, activated by steam at 820℃, microporous activated carbons were made with BET surface area 1076 m2, total volume 0.81 m3/g, micropore volume rate 63%, mesopore volume rate 33%, methylene blue value(MB)180 mg/g and iodine value 1012 mg/g. Based on the steam-activated carbons, phosphoric acid reactivation at 820℃ can significantly increase BET surface area(1 608 m2/g)and total pore volume(1.17 cm3/g), especially enhance the development of mesopore volume(61%)and simultaneously maintain definite proportion of micropore volume(37%). The prepared activated carbons showed much higher adsorption value of methylene blue(330 mg/g)and iodine value(1326 mg/g). Related Articles | Metrics