Table of Content

30 June 2004, Volume 24 Issue 2 Previous Issue    Next Issue

研究报告

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STUDY ON INDUSTRIAL TECHNOLOGY OF GASIFICATION OF BIOMASS WITH FLUIDIZED-BED YING Hao;JIANG Jian-chun;DAI Wei-di;LIU Shi-cai;GAO Yi-wei 2004, 24 (2):  1-5.  Abstract ( 579 )   PDF (742KB) ( 645 )   Save Industrial technology of gasification and catalytic gasification of biomass with inner recycled conical fluidized bed as gasifier was discussed.Experimental results indicated that calorific value of gas from wheat straw gasification is higher than those from rice straw and husk,while calorific value of gas from sawdust gasification is the highest.Calorific value of gas from non-catalytic gasification is about 40% higher than that from down-up gasifier.Catalytic gasification experiment showed:CaO has the effect to markedly increase calorific value and reduce the content of CO in gas;Na2CO3 has the effect to enhance the content of H2.When reaction temperature reached 800℃,addition of catalytic agent can obviously enhance the gas calorific value. Related Articles | Metrics

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SYNTHESIS OF POLYURETHANE FROM ACETIC ACID LIGNIN AND ITS PROPERTIES WANG Peng;XIE Yi-min;AORI Ge-le;ZHAN Huai-yu;GAN Ding-neng 2004, 24 (2):  6-10.  Abstract ( 586 )   PDF (748KB) ( 796 )   Save Acetic acid lignin(AL) from acetic acid pulping was isolated and purified.Chemical structure and molecular weight of AL were studied with infrared spectroscopy and GPC determination.Thermal and physical characteristics of AL-based polyurethane were determined by TGA and DSC respectively.The results showed that AL has the typical structure of polyol.A part of AL was acetylated.However,the dissolution property of AL was good and molecular weight of AL was relatively high.As compared with PEG-based polyurethane(PU),AL-based polyurethane has higher glass transition temperature and lower degradation ratio of polyurethane below 600℃.These indicated that AL-based polyurethane had relatively better heat resistance.In addition,tensile strength and elongation of AL-based polyurethane,which were decreased as the lignin amount was increased,were lower compared with PEG-based polyurethane.These would mean that the rigidity of AL-based polyurethane were increased by addition of AL. Related Articles | Metrics

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TREATMENT OF WASTE WATER OF HIGH-ORGANIC-SUBSTANCE- CONTENT BY CATIONIC TANNIN-POLYCHLORIDE COMPLEX COAGULANT WU Jian-ping;FANG Hua;LUO Wen-jing;XIE Jia-li 2004, 24 (2):  11-14.  Abstract ( 543 )   PDF (685KB) ( 862 )   Save Forty mL 37% formaldehyde solution and 80 mL 33% dimethylamine water solution reacted at room temperature for 1.5 h and pre-reaction solution was then attained.Fifty-four point seven gram of larch tannin extract and 100 mL of the pre-reaction solution reacted at 60℃ for 2.5 h,and the mixture was then rapidly cooled to room temperature.Ammonium chloride and hydrochloric acid were added to adjust the pH value of the mixture to 4.5-5.0,followed by reacting at room temperature for 1.0 h.The product(cationic tannin,CAT) reacted with aluminum polychloride(PAC) at certain temperature for certain time and a complex flocculant was then attained.The optimal operating conditions were obtained as follows:CAT:PAC 1:4(mass ratio),reaction temperature 30℃ and reaction time 1 h.The flocculant was used in high-organic-substance-content waste water treatment at room temperature at an amount of 100 mg/L.The removals of filterable CODCr colour and turbidity were over 60%,70% and 80%,respectively. Related Articles | Metrics

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STUDY ON α-PINENE ISOMERIZATION CATALYZED BY SO42-/ZrO2-TiO2 SOLID SUPERACID LUO Jin-yue;YANG Yun;FAN Yi-min;AN Xin-nan 2004, 24 (2):  15-19.  Abstract ( 633 )   PDF (1193KB) ( 787 )   Save Solid superacids of SO42-/ZrO2-TiO2 type were prepared and used as the high-activity catalysts for (α-pinene) isomerization in this study.The products of isomerization reaction were identified by using GC-MS.In the (isomerization) reaction,the main product is camphene,and by-products are tricyclene and α-terpinene.Effects of conditions for preparation of SO42-/ZrO2-TiO2 catalysts,such as ratio of Ti to Zr,concentration of H2SO4,calcination temperature with respect to its catalytic activity,were investigated.Results showed that the optimum conditions for the preparation of SO42-/ZrO2-TiO2 catalysts are as follows: ratio of Ti to Zr 4(molar ratio),calcinations temperature 600℃,and H2SO4 concentration 0.5 mol/L.Under these conditions,the main factors affecting the reaction were investigated in the work.Optimum conditions for α-pinene isomerization reaction were as follows:reaction time 1-2 h,isomerization temperature 130℃±2℃,and the ratio of solid superacids to α-pinene 0.03(mass ratio).Under these conditions,α-pinene conversion was 96.58%,and camphene selectivity was 57.39%.Furthermore,the effect of storage time of the catalysts on the reaction was discussed,and the regeneration experiments of catalysts were carried out. Related Articles | Metrics

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STUDY ON CORROSION INHIBITION PERFORMANCE OF NON-WOODY MAGNESIUM LIGNOSULFONATE AND ITS OXIDATION REACTION LOU Hong-ming;QIU Xue-qing;ZHANG You-mao;YANG Dong-jie 2004, 24 (2):  20-24.  Abstract ( 626 )   PDF (729KB) ( 644 )   Save Non-woody magnesium lignosulfonate(ML) is produced as a by-product in the sulphite non-wood pulping,which is a very abundant and innoxious biomass resource.Corrosion inhibition performances of ML in circulating cooling water have been studied in this paper.Corrosion inhibition ratio of ML to 20# carbon steel determined by weight-loss method reaches 22%.Corrosion inhibition ratio decreases with increase of running concentration of ML.A new corrosion inhibitor,which is called modified magnesium lignosulfonate(MML),is modified from ML by oxidation reaction.Its corrosion inhibition ratio to 20# carbon steel determined by weight-loss method reaches 75%,and increases by the increase of running concentration.By viscosity determination and IR spectrum analysis,it is found that ML is partly degraded by oxidation reaction.Both GML and ML belong to cathodic corrosion inhibitor by electrochemical polarization determination. Related Articles | Metrics

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EFFECTS OF CULTURE CONDITIONS ON FERMENTATION OF PENTOSE BY PICHIA STIPITIS JI Geng-sheng;YONG Qiang;YU Shi-yuan 2004, 24 (2):  25-28.  Abstract ( 638 )   PDF (712KB) ( 1061 )   Save Effects of culture condition,including nitrogen source,pH value and temperature on pentose(mainly xylose) fermentation by Pichia stipitis P2 were investigated.Both growth and xylose fermentation were as good with (urea) as a sole nitrogen source as with peptone as a sole nitrogen source.The optimum pH value and temperature range of the growth of Pichia stipitis P2 were 4.6-5.8 and 25-30℃,respectively.When cultural temperature was 25℃ and 35℃,the optimum pH value range of the xylose fermentation by P2 was 3.4-4.2 and 3.8-5.0,respectively. Related Articles | Metrics

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STUDY ON FIRE-RETARDATION MECHANISM OF FIRE-RETARDANT FRW BY CONE CALORIMETRY WANG Qing-wen;LI Jian 2004, 24 (2):  29-34.  Abstract ( 732 )   PDF (835KB) ( 1152 )   Save Fire-retardation mechanism of FRW,a fire-retardant of new formulation for wood,was studied by CONE calorimetric analysis.Wood specimens treated with the composite fire-retardant FRW(FZ),its components guanylurea phosphate(GUP,GZ) and boric acid(BZ) respectively were tested and the data of heat release,mass loss,smoke formation and the composition of tail gas were recorded simultaneously.By analyzing these data,it was concluded that:1)The combustion parameters of wood,including rate of heat release(RHR),total heat release(THR),effective heat of combustion(EHC),mass loss rate(MLR),smoke ratio(SR),specific extinction area(SEA),concentration of CO2 and the yield of CO2(YCO2),were decreased considerably by the treatment of FRW;2)There is a strong synergistic effect of fire retardance between GUP and boric acid;3)The trend of MLR curve of FZ was similar to its RHR curve,weight loss and heat release were happened mainly in flaming phase;4)Char formation of wood was markedly accelerated by FRW,which indicated that catalytic charring effect of FRW on wood is the primary side in its fire-retardation mechanism. Related Articles | Metrics

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LACTIC ACID FERMENTATION BY IMMOBILIZED LACTOBACILLUS DELBRUECKII CELLS USING CELLULOSIC HYDROLYSATE SHEN Xue-liang;XIA Li-ming 2004, 24 (2):  35-38.  Abstract ( 594 )   PDF (696KB) ( 592 )   Save Cellulosic material is the most abundant renewable carbon source in the world.Using cellulosic hydrolysate instead of starch for lactic acid production is meaningful.Lactobacillus delbrueckii cells were immobilized by entrapped into calcium alginate gels.The immobilized cells were quite stable,and could utilize cellulosic hydrolysate to produce lactic acid efficiently.Optimum fermentation temperature was 48℃,and wheat bran hydrolysate could promote the production of lactic acid obviously.Comparing with free cells,the fermentation term of immobilized cells was (shortened),and the yield of lactic acid could reach 90.1% on cellulosic hydrolysate from corn cob.During 16 repeated batch fermentation processes,average yield of lactic acid was 88.6% using the immobilized cells on cellulosic hydrolysate.Continuous fermentation process was carried out in a 250 mL column reactor with immobilized cells on cellulosic hydrolysate,the lactic acid yield and production efficiency under 0.12 h-1 dilution rate were 80.2% and 4.97 g/(L·h),respectively. Related Articles | Metrics

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STUDY ON THE TECHNOLOGICAL CONDITIONS OF PREPARING POLYURETHANE RESINS FROM LIQUEFIED BENZYLATED WOOD CHENG Fa;QI Hong-juan;LI Hou-ping;WEI Yu-ping 2004, 24 (2):  39-42.  Abstract ( 596 )   PDF (503KB) ( 635 )   Save Polyurethane resins were synthesized with liquefied benzylated wood using dibasic esters(DBE) as liquefaction reagent and toluene diisocyanate(TDI).Various reaction factors including amount of TDI,kind of plasticizer,amount of catalyst and weight percentage gain(WPG) of wood were taken into account to study their influences on the performance of polyurethane films.Optimal technological conditions were obtained as follows:WPG of modified wood 63%-80%,amount of modified wood 8 g,amount of TDI 14-16 mL,amount of catalyst 0.4%,molecular mass of plasticizer 400.Under this condition,the performance parameters of polyurethane films synthesized,such as drying time,pencil hardness and adhesion could attain the GB standard of polyurethane coating.The potential of the project will be great in the view of both efficient use of raw material and environmental protection. Related Articles | Metrics

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CATALYTIC EFFECT OF NaH2PO2 IN ESTERIFICATION OF CELLULOSE BY POLYCARBOXYLIC ACID FANG Gui-zhen 2004, 24 (2):  43-46.  Abstract ( 785 )   PDF (507KB) ( 1035 )   Save Polycarboxylic acids as esterification agent and inorganic salts as catalyst were used in the research of cellulose cross-linking reaction.This soluble cross-linking system is a poison-free and pollution-free system.The mechanism and effect of catalyst NaH2PO2 on esterification of cellulose by polycarboxylic acid were studied by FTIR spectra.Experimental results show that NaH2PO2 played catalysis role in both stages of esterification between cellulose and polycarboxylic acid,which are:1)The intermediate anhydrides of five-member-ring were formed by dehydration of polycarboxylic acids,during which the formation temperature was reduced by the catalyst;2)Esters were formed through nucleophilic substitution between the five-member-ring anhydride and cellulose during which,the conversion of esterificative products was enhanced by the catalyst.The catalysis effect of NaH2PO2 is remarkable. Related Articles | Metrics

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RETENTION OF XYLAN EXTRACTIVES DURING ULTRAFILTRATION JIANG Hua;XU Yong;YONG Qiang;YU Shi-yuan 2004, 24 (2):  47-51.  Abstract ( 689 )   PDF (602KB) ( 510 )   Save The retention of xylan extractives during ultrafiltration was investigated.It was shown that the retention for xylan was more than 90% using GC5,GC10 and GC30 membranes.Operating parameters such as transmembrane pressure,feed concentration and xylan concentration in feed had hardly any effect on the retention for xylan with the membranes mentioned above.The retention for xylan with PS6 membrane was between 76% and 87%,and it increased with the increase in transmembrane pressure,feed concentration or xylan concentration in feed.The retention for non-reducing sugars was below 15% in all experiment conditions using these four kinds of membrane.It was concluded that these membranes were preferable for the purification of xylan extractives,in which GC membranes were more suitable for the purification process than PS membrane. Related Articles | Metrics

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EXTRACTION OF SOYBEAN LIPOXYGENASE AND FACTORS AFFECTING ITS ENZYME ACTIVITY CAI Kun;FANG Yun;XIA Yong-mei;SHI Yu-gang;XU Yi-ming 2004, 24 (2):  52-56.  Abstract ( 810 )   PDF (911KB) ( 1368 )   Save Lipoxygenase(LOX) can catalyze oxygenation of the(Z,Z)-1,4-pentadiene moiety of polyunsaturated fatty acids into enantiomeric hydroperoxide fatty acids with(Z,E)-conjugated diene moiety.In this paper,several methods were used for extracting LOX from defatted soybean powder,and LOX activity was measured.Experiment results show that the total enzyme activity 6.71×107 U/10 g(defatted soybean flour) obtained by water-leaching is the highest with corresponding specific enzyme activity 8.61×105 U/mL(enzyme preparation).The loss of enzyme activity is more than 1/2 after two salting-out steps or coprecipitation process.Specific activity of LOX 9.42×107 (U/g)(powdered enzyme) obtained by alkali-dissolving and acid-leaching followed by two salting-out steps is the highest of all.Free LOX loses 79% of its activity sharply at room temperature after 7 days, indicating that low storage temperatures to maintain high enzyme activity is preferred.At pH value 9,LOX exhibits the highest enzyme activity.Addition of some salts,sugar,polyol or organic electrolytes,especially EDTA-Na2 can increase the storage stability and thermostability of LOX.By addition of 1%(mass ratio) EDTA-Na2,the activity of LOX was kept 80% of the original after 42 day,and only 6% activity was lost by heat treatment at 50℃ for 60 min. Related Articles | Metrics

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EXTRACTION TECHNOLOGY OF OLIGOMERIC PROANTHOCYANIDINS YANG Lei;SU Wen-qiang;LI Yan-jie;SONG Hao;LIU Wen-bin 2004, 24 (2):  57-60.  Abstract ( 655 )   PDF (626KB) ( 1176 )   Save Extraction and separation of oligomeric proanthocyanidins(OPC) from larch bark and quantitative determination of OPC has been carried out.Results of orthogonal test indicated the optimum extraction condition of OPC as follows:ratio of liquor to material 10:1,reflux extraction at 85℃ for 2 h with water.After ethanol precipitation,OPC was separated by ethyl acetate-ligroin system.Content of OPC was determined by normal butyl alcohol-hydrochloric acid method at 546 nm to be over 90%. Related Articles | Metrics

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HPLC DETERMINATION OF RESVERATROL CONTENT IN POLYGONUM CUSPIDATUM AND THE STABILITY OF RESVERATROL CAO Yong;YU Hua-zhong;ZHANG Min;LI Guo-zhang;XIAO Lang-tao 2004, 24 (2):  61-64.  Abstract ( 981 )   PDF (778KB) ( 2359 )   Save Resveratrol is one of the most feasible medicine for preventing human cancer.It is unstable against light and heat.An extracting method was established in this study,which is simple,and of high yield.Study on the conditions of high performance liquid chromatography for the determination of resveratrol content was investigated to be as follow:Shim-park CLC-ODS column(150 mm×6.0 mm,i.d.5 μm),mobil phase CH3CH2CN:H2O(14:59),flow rate 1.0 mL/min,wavelength 306 nm.The lineal correlation between content of resveratrol and peak area is good.The lower detection limit was 10 ng/mL. Related Articles | Metrics

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TREATMENT OF HEAVY-METAL WASTE WATER WITH SULFOHYDRYL CELLULOSE SHI Wen-jian;PENG Meng-cheng 2004, 24 (2):  65-68.  Abstract ( 752 )   PDF (574KB) ( 1257 )   Save Sulfohydryl cellulose(SC) was synthesized by reacting cellulose with sulfohydryl acetic acid in the medium of acetic anhydride and acetic acid.Alkali was added into heavy-metal waste water to adjust pH value 9-10,followed by sedimentation and filtration.Then the filtrate was adjusted to pH value 5-7 and flowed through SC tube to remove Cd(II),Pb(II),Cu(II),Hg(II) in the waste water.SC tube was regenerated by dilute hydrochloric acid.Conditions of treatment and regeneration,along with adsorption mechanism were studied.Saturated adsorptive capacity of SC was more than 0.2 mol/kg SC when sulfohydryl content in SC was more than 2%.The concentrations of metal ions Cd(II),Pb(II),Cu(II),Hg(II) in the filtrate were all below 0.05 mg/L.The regenerated SC can be reused. Related Articles | Metrics

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STUDY ON LEACHING AND PURIFYING METHOD OF FLAVONES FROM MARCHANTIA POLYMORPHA L. ZHU Hua;XIAO Jian-bo;ZHONG Shi-an;ZHOU Chun-shan 2004, 24 (2):  69-72.  Abstract ( 671 )   PDF (550KB) ( 704 )   Save The optimum technology of extracting flavones in Marchantia polymorpha L.was studied by orthogonal test.An orthogonal test table L16(45) was used with the factors of extracting time,temperature,number of extraction times,ethanol concentration and ratio of solid-to-liquid.The content of flavones was determined by spectrophotometry.The optimum technology was:temperature 70℃,time 0.5 h,three times of extraction,80% EtOH as extracting solvent,stock ratio 1:15.The extraction yield is 1.90%,and its purification about 95.83% with this method. Related Articles | Metrics

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PREPARATION OF MICROPARTICLE OF QUERCETIN BY SUPERCRITICAL ANTI-SOLVENT PROCESS LIU Xue-wu;LI Zhi-yi;HAN Bing;XIA Yuan-jing;YUAN Ta-liang 2004, 24 (2):  73-76.  Abstract ( 621 )   PDF (593KB) ( 878 )   Save Supercritical anti-solvent(SAS) process is a recently developed technology to produce micro- and nano-particles.This paper presents a continuous apparatus to conduct SAS process experiments.With the apparatus,the effects of pressure,temperature and flow ratio of CO2 to the solution on the shape and size of the particles are studied in a quercetin-ethanol-CO2 system.The experimental results show that spherical quercetin microparticles with diameters ranging 1-6 μm can be obtained by SAS process when ethanol is used as organic solvent.The most effective parameter on the shape and size of the particles is pressure,followed by temperature and the last is flow ratio of CO2 to solution. Related Articles | Metrics

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PREPARATION AND CHARACTERIZATION OF CROSS-LINKED KONJAC GLUCOMANNAN GRANULES ; 2004, 24 (2):  77-79.  Abstract ( 550 )   PDF (1KB) ( 277 )   Save Related Articles | Metrics

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STUDY ON MICROWAVE EXTRACTION OF PIGMENT FROM CERCIS CHINENSIS BUNGE LI Yu;GAO Hong;OU Bu-qing 2004, 24 (2):  80-82.  Abstract ( 619 )   PDF (547KB) ( 683 )   Save As a new method of extraction,microwave was used to extract pigment from flowers of Cercis chinensis Bunge.The extraction processes were investigated to obtain the optimal conditions as follows:dry flower 0.200 0 g,(solvent) 95% alcohol,ratio of raw material to solvent 1:50(g:mL),microwave power 648 W,extraction time 30 s,twice of extraction.Results are:extraction rate 92.1%,yield 9.48% and absorbance E(1%,549 nm) 53.3.Compared with normal solvent extraction,microwave extraction time could be reduced from 24 h to 30 s,and the extraction yield (increase) from 90.2% to 92.1%. Related Articles | Metrics

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RESEARCH ON PREVENTION AND ELIMINATION OF AGRICULTURAL PESTS BY GINKGO PHENOLS AND PHENOLIC ACIDS SHI Qi-tian 2004, 24 (2):  83-86.  Abstract ( 565 )   PDF (786KB) ( 802 )   Save Ginkgo extract,ginkgo phenols and ginkgo phenolic acids were extracted from exotesta of Ginkgo biloba L.followed by separation and isolation procedures respectively.Ginkgo extract contains ginkgo phenols(55.5%) and ginkgolic acids(14.2%) which are the effective constituents against pests.Experiments on prevention and elimination of agricultural pests were carried out.Results showed that ginkgo phenols and phenolic acids were effective against cotton aphids,vegetable aphids,cabbage caterpillars and thrips,the effectiveness of which were comparable with those of fenralete phoxim,imidacloptid and decis.It is a pesticide from natural resources of low toxicity(LD50>(5000 mg/kg)).The utilization of ginkgo extract not only makes use of exotesta of G.biloba,which is abundant but not yet (utilized),discarded as waste to pollute environment,but also provides a non-toxic pesticide for the production of green vegetables and fruits. Related Articles | Metrics

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EXTRACTION OF ESSENTIAL OIL FROM MICROSORIUM FORTUNEI AND ITS ANALYSIS BY GC-MS SUN Cui-rong;CHENG Cun-gui; 2004, 24 (2):  87-88.  Abstract ( 659 )   PDF (288KB) ( 771 )   Save The essential oil from the aerial parts of Microsorium fortunei was extracted by hydrodistillation method.The oil was analyzed by GC-MS.More than 23 peaks were separated and 21 compounds representing 98.39% of the oil were identified.The main constituents in the oil of M.fortunei are 1-hexanol,hexanoic acid and glutamic acid. Related Articles | Metrics

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STUDY ON CHEMICAL CONSTITUENTS IN ETHYL ACETATE FRACTION OF ALCOHOLIC EXTRACT FROM THE FLOWER OF BOMBAX MALABARICUM DC. WANG Hui;ZENG He-ping;ZENG Zhi 2004, 24 (2):  89-91.  Abstract ( 538 )   PDF (424KB) ( 796 )   Save Chemical constituents in ethyl acetate fraction of alcoholic extract from the flower of Bombax malabaricum DC.were investigated by using GC-MS.Sixty peaks were separated,and 46 compounds were identified.Relative content of the constituents were determined by GC with area normalizing method.The identification ratio was 87.11%.The main chemical components of the fraction are palmitic acid,ethyl palmitate,β-sitosterol,etc. Related Articles | Metrics

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APPLICATION OF POROUS CARBON IN INDOOR-AIR- POLLUTION CONTROL CHENG Yan;YIN Hua-qiang;LIU Yong-jun;PEI Wei-zheng;CHEN Jun-hui 2004, 24 (2):  92-96.  Abstract ( 661 )   PDF (587KB) ( 1449 )   Save Classification and current control of indoor-air-pollution are described briefly and the application of porous carbon in indoor-air-pollution is reviewed.Moreover,problems existing in indoor-air-pollution control are analyzed and related ways to solve these problems are put forward from aspects of material,technology,equipment,etc. Related Articles | Metrics

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RESEARCH PROGRESS ON UREA-FORMALDEHYDE ADHESIVE OF LOW FORMALDEHYDE EMISSION YAN Bing;OU Yi-fang;CAO De-rong;MA Zhi-jun 2004, 24 (2):  97-101.  Abstract ( 575 )   PDF (439KB) ( 1698 )   Save Recent researches on the mechanisms on synthesis,curing and formaldehyde emission of UF adhesive are reported.Some measures such as reducing the toxicity of UF resins,improving the adhesive strength,water resistance and anti-ageing property of UF resins are also summarized.Attentions were paid to the mechanisms of the modified process during preparation and after curing of the resin. Related Articles | Metrics

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PROGRESS ON RESEARCH OF NEW EXTRACTION TECHNIQUES FOR PHYTOCHEMICAL PESTICIDES ZHAO Shu-ying;SONG Zhan-qian;WANG Qiu-fen;GAO Hong 2004, 24 (2):  102-106.  Abstract ( 653 )   PDF (566KB) ( 1135 )   Save Researches on mechanism and characteristics of new extraction techniques such as supercritical fluid solvent extraction,microwave-assisted solvent extraction,ultrasonic solvent extraction and liquid membrane solvent extraction,as well as their applications in extraction and separation of phytochemical pesticides were described. Progress in phytochemical pesticides was reviewed and its trend of development was discussed.The authors explained their own views through their experiences of extracting azadirachtin from neem seed using supercritical fluid solvent extraction,microwave-assisted solvent extraction and ultrasonic solvent extraction. Related Articles | Metrics