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Table of Content
28 June 2003, Volume 11 Issue 3
    RESEARCH PAPERS
    Influence of Metal Sulfides as Anode Catalysts on Performance of H2S SOFC
    ZHONG Li, LIU Man, WEI Guolin, CHUANG Karl
    2003, 11(3):  245-248. 
    Abstract ( 648 )   PDF (1486KB) ( 242 )  
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    Two anode catalysts with Pt, MoS2 and composite metal sulfides (MoS2+NiS), are investigated
    forelectrochemical oxidation of hydrogen sulfide in solid oxide fuel cell (SOFC) at
    temperatures 750-850℃. Thecatalysts comprising MoS2 and MoS2+NiS exhibited good electrical
    conductivity and catalytic activity. MoS2 andcomposite catalysts were found to be more
    active than Pt, a widely used catalyst for high temperature H2S/O2fuel cell at 750-850℃.
    However, MoS2 itself sublimes above 450℃. In contrast, composite catalysts containingboth
    Mo and transition metal (Ni) are shown to be stable and effective in promoting the
    oxidation of H2S in SOFCup to 850℃. However, electric contact is poor between the platinum
    current collecting layer and the compositemetal sulfide layer, so that the cell performance
    becomes worse. This problem is overcome by adding conductiveAg powder into the anode layer
    (forming MoS2+NiS+Ag anode material) to increase anode electrical conductanceinstead of
    applying a thin layer of platinum on the top of anode.
    Theoretical Study and Analysis on Properties of Filter Aids
    TAN Wei, LU Shuqun, WU Yuntao, ZHU Qixin
    2003, 11(3):  249-252. 
    Abstract ( 885 )   PDF (1133KB) ( 227 )  
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    Pressure filtration and filter aids should be adopted in filtration of high-viscosity
    molten chemical fibercontaining foreign materials and gel particles. Theoretical analysis
    and argumentations on manners of assistedfiltration and specific requirements of filter
    aids are performed. Measurement and comparison on properties ofseveral filter aids are also
    carried out, conclusions and suggestions are put forward.
    Estimation of the Isotherms of Phenol on Activated Carbons and Polymeric Adsorbents under
    Supercritical Condition
    XI Hongxia, XIE Lanying, LI Xiangbin, LI Zhong
    2003, 11(3):  253-256. 
    Abstract ( 799 )   PDF (1451KB) ( 263 )  
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    A method named as "volume-expanding and pressure-reducing adsorption" is proposed. It can
    be usedto measure the isotherms under supercritical condition. The adsorption isotherms of
    phenol on activated carbonsand polymeric adsorbents are estimated and compared respectively
    for the systems of "phenol-activated carbon-supercritical fluid CO2" and "phenol-polymeric
    adsorbent-supercritical fluid CO2". The results show that theamount of phenol adsorbed on
    the activated carbons and the polymeric adsorbents under the supercritical conditionis much
    less than that under the general condition, which can be utilized to develop a technology
    regenerating theactivated carbon with supercritical fluid. Moreover, the effects of ethyl
    alcohol, used as the third component, on theisotherms of phenol on the activated carbons
    and polymeric adsorbents under the supercritical condition are alsoinvestigated.
    Minimization of the Flowrate of Fresh Water and Corresponding Regenerated Water in Water-
    using System with Regeneration Reuse
    XU Dongmei, HU Yangdong, HUA Ben, WANG Xiulin
    2003, 11(3):  257-263. 
    Abstract ( 835 )   PDF (2438KB) ( 243 )  
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    A sequential three-step programming method is proposed for determining the minimum flowrate
    of freshwater and corresponding regenerated water in water-using system of single
    contaminant with regeneration reuse.In step 1, a programming with the objective of min fws
    is used to determine the minimum flowrate of fresh water,in which the mathematical
    representation is a mixed integer nonlinear programming (MINLP1). Then under thesame
    constraints with step 1, a programming with the objective of min freg in step 2 and a
    programming withthe objective of min Cr in step 3 are subsequently used to determine the
    minimum flowrate of regenerated waterand the minimum inlet concentration to regeneration
    process corresponding to the minimum flowrate of fresh waterbased on step 1. The method is
    easy to apply because we only need to change the objective function but keep theconstraints
    constant to go along the following steps after step 1. In addition, the relationship
    between the freshwater flowrate required, fws, and inlet concentration to regeneration
    process, Cr, is investigated. It is found thatthere exist three relationships between fws
    and Cr, which indicate three possibilities for Cb: below the pinch, abovethe pinch or at
    the pinch. Therefore, a new conclusion is drawn, which differs from that "regeneration of
    water atpinch minimizes fresh water flowrate" derived in literature and indicates that in
    some cases, regeneration at otherpoint also minimizes fresh water flowrate.
    The Swelling Equilibria of N-isopropylacrylamide Based Hydrogel in Aqueous Solution of
    Ethanol
    XU Xiaoping, HUTHER Andreas, MAURER Gerd
    2003, 11(3):  264-268. 
    Abstract ( 1096 )   PDF (1701KB) ( 227 )  
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    N-isopropylacrylamide (NIPAAm) was used to synthesize NIPAAm homopolymer (nonionized)
    andNIPAAm-sodium methacrylate copolymer (ionized). The swelling equilibria for both gels
    were obtained in aqueoussolution of ethanol with concentration ranging from 0 to 100%(by
    mass) at 25℃. The swollen gel in water shrankfirst with the addition of a small amount of
    ethanol and then reswelled with further addition of ethanol showing notonly a discontinuous
    volume phase transition but also a typical reentrant phenomenon. A thermodynamic modelbased
    on the UNIQUAC with the "free-volume" contribution was applied to correlate and predict the
    swellingbehavior of the poly(NIPAAM)-gels in ethanol-water mixture.
    Effect of Graft Yield on the Thermo-Responsive Permeability Through Porous Membranes with
    Plasma-Grafted Poly (N-isopropylacrylamide) Gates
    CHU Liangyin, ZHU Jiahua, CHEN Wenmei, NIITSUMA Takuya, YAMAGUCHI Takeo, NAKAO Shin-ichi
    2003, 11(3):  269-275. 
    Abstract ( 686 )   PDF (2867KB) ( 256 )  
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    The effect of graft yield on both the thermo-responsive hydraulic permeability and the
    thermo-responsivediffusional permeability through porous membranes with plasma-grafted
    poly(N-isopropylacrylamide) (PNIPAM)gates was investigated. Both thermo-responsive flat
    membranes and core-shell microcapsule membranes with a widerange of graft yield of PNIPAM
    were prepared using a plasma-graft pore-filling polymerization method. The graftedPNIPAM
    was formed homogeneously throughout the entire thickness of both the flat polyethylene
    membranes andthe microcapsule polyamide membranes. Both the hydraulic permeability and the
    diffusional permeability wereheavily dependent on the PNIPAM graft yield. With increasing
    the graft yield, the hydraulic permeability (waterflux) decreases rapidly at 25℃ because
    of the decrease of the pore size; however, the water flux at 40℃ increasesfirstly to a
    peak because of the increase of hydrophobicity of the pore surface, and then decreases and
    finally tends tozero because of the pore size becoming smaller and smaller. For the
    diffusional permeability, the temperature showsdifferent effects on the diffusional
    permeability coefficients of solutes across the membranes. When the graft yieldwas low, the
    diffusional coefficient of solute across the membrane was higher at temperature above the
    lower criticalsolution temperature (LCST) than that below the LCST; however, when the graft
    yield was high, the diffusionalcoefficient was lower at temperature above the LCST than
    that below the LCST. It is very important to choose ordesign a proper graft yield of PNIPAM
    for obtaining a desired thermo-responsive "on/of" hydraulic or diffusionalpermeability.
    Calorimetric Determination of Enthalpy of Formation of Natural Gas Hydrates
    GAO Jun, Kenneth N. Marsh
    2003, 11(3):  276-279. 
    Abstract ( 495 )   PDF (1376KB) ( 296 )  
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    This paper reports the measurements of enthalpies of natural gas hydrates in typical
    natural gas mixturecontaining methane, ethane, propane and iso-butane at pressure in the
    vicinity of 2000 kPa (300 psi) and 6900 kPa(1000psi). The measurements were made in a
    multi-cell differential scanning calorimeter using modified highpressure cells. The
    enthalpy of water and the enthalpy of dissociation of the gas hydrate were determined
    fromthe calorimeter response during slow temperature scanning at constant pressure. The
    amount of gas released fromthe dissociation of hydrate was determined from the pumped
    volume of the high pressure pump. The occupationratio (mole ratio) of the water to gas and
    the enthalpy of hydrate formation are subject to uncertainty of 1.5%.The results show that
    the enthalpy of hydrate formation and the occupation ratio are essentially independent of
    pressure.
    Adsorption and Transfer Properties for Toluene and p-Dichlorobenzene in Dense CO2/Silica
    Gel Packed Bed System by Moment Method and Time-Domain Analysis
    YANG Xiaoning
    2003, 11(3):  280-288. 
    Abstract ( 702 )   PDF (2921KB) ( 221 )  
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    Based on chromatographic theory, the moment method and the time-domain fitting analysis
    wereapplied to measure and evaluate the adsorption equilibrium constant and mass transfer
    properties (axial dispersioncoefficient and effective intra- particle diffusivity) for
    toluene and p-dichlorobenzene on silica gel adsorbent in thesubcritical and supercritical
    CO2. An apparatus based on supercritical fluid chromatography was established and
    theexperiments were performed at temperatures of 298.15-318.15 K and pressures of 7.5-17.8
    MPa. The two methodshave been compared. The results show that for the systems studied here
    the moment method can give reasonablevalues for both adsorption equilibrium constant and
    mass transfer properties, but the time-domain analysis only canobtain the adsorption
    equilibrium constant. The dependence of adsorption equilibrium constant and mass
    transferproperties on temperature and pressure was investigated.
    Modeling of a SrCe0.95Yb0.05O3-α Hollow Fibre Membrane Reactor for Methane Coupling
    TAN Xiaoyao, YANG Naitao, K.Li
    2003, 11(3):  289-296. 
    Abstract ( 951 )   PDF (2505KB) ( 213 )  
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    Proton-hole mixed conductor, SrCe0.95Yb0.05O3-α(SCYb), has the potential to be used as a
    mem-brane for dehydrogenation reactions such as methane coupling due to its high C2-
    selectivity and its simplicity forfabricating reactor systems. In addition, the mixed
    conducting membrane in the hollow fibre geometry is capable ofproviding high surface area
    per unit volume. In this study, mechanism of methane coupling reaction on the SCYbmembrane
    was proposed and the kinetic parameters were obtained by regression of experimental data. A
    math-ematical model describing the methane coupling in the SCYb hollow fibre membrane
    reactor was also developed.With this mathematical model, various operating conditions such
    as the operation mode, operation pressure andfeed concentrations affecting performance of
    the reactor were investigated. The simulation results show that thecocurrent flow in the
    reactor exhibits higher conversion of methane and higher yield of ethylene compared to
    thecountercurrent flow. In order to achieve the highest C2 yield, especially of ethylene,
    pure methane should be usedas feed and the operating pressure be 300kPa. Air can be used as
    the source of oxygen for the reaction and itsoptimum feed velocity is twice of the methane
    feed velocity. The air pressure in the lumen side should be kept thesame as or slightly
    lower than the pressure of shell side.
    Process Design for Separating C4 Mixtures by Extractive Distillation
    LEI Zhigang, CHEN Biaohua, LI Jianwei
    2003, 11(3):  297-301. 
    Abstract ( 782 )   PDF (1657KB) ( 294 )  
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    C4 components are useful in industry and should be separated as individuals. A new process
    wasproposed to separate them by extractive distillation, with the advantages of low
    equipment investment, energyconsumption and liquid load in the columns. One principle to
    improve the extractive distillation process was putforward. Moreover, the analysis of
    operation state of the new process was done. There were eight operation statesfound for the
    whole process, but only one operation state was desirable. This work provides a way to
    effectivelyseparate C4 mixtures and helps the reasonable utilization of C4 resource.
    Kinetics and Mechanism of Decomposition of Nano-sized Calcium Carbonate under Non-
    isothermal Condition
    LIU Runjing, CHEN Jianfeng, GUO Fen, YUN Jimmy, SHEN Zhigang
    2003, 11(3):  302-306. 
    Abstract ( 709 )   PDF (1724KB) ( 305 )  
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    Experiments on thermal decomposition of nano-sized calcium carbonate were carried out in a
    thermo-gravimetric analyzer under non-isothermal condition of different heating rates (5 to
    20 K@min-1). The Coats andRedfern’s equation was used to determine the apparent activation
    energy and the pre-exponential factors. Themechanism of thermal decomposition was evaluated
    using the master plots, Coats and Redfern’s equation and thekinetic compensation law. It
    was found that the thermal decomposition property of nano-sized calcium carbonatewas
    different from that of bulk calcite. Nano-sized calcium carbonate began to decompose at 640
    ℃, which was 180℃lower than the reported value for calcite. The experimental results of
    kinetics were compatible with the mechanismof one-dimensional phase boundary movement. The
    apparent activation energy of nano-sized calcium carbonate wasestimated to be 151kJ@mol-1
    while the literature value for normal calcite was approximately 200kJ@mol-1. Theorder of
    magnitude of pre-exponential factors was estimated to be 109 s-1.
    Simulation and Optimization for Thermally Coupled Distillation Using Artificial Neural
    Network and Genetic Algorithm
    WANG Yanmin, YAO Pingjing
    2003, 11(3):  307-311. 
    Abstract ( 662 )   PDF (1585KB) ( 304 )  
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    In this paper, a new approach using artificial neural network and genetic algorithm for the
    optimizationof the thermally coupled distillation is presented. Mathematical model can be
    constructed with artificial neuralnetwork based on the simulation results with ASPEN PLUS.
    Modified genetic algorithm was used to optimize themodel. With the proposed model and
    optimization arithmetic, mathematical model can be calculated, decisionvariables and target
    value can be reached automatically and quickly. A practical example is used to
    demonstratethe algorithm.
    State Space Approach to Mass Exchange Network Synthesis
    MA Weijun, HU Shanying, LI Yourun, SHEN Jingzhu
    2003, 11(3):  312-317. 
    Abstract ( 691 )   PDF (1835KB) ( 228 )  
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    State space approach is an effective method to mass-exchange network (MEN) synthesis. By
    decom-posing the network into two interactive parts, a distribution network and a process
    operator, the synthesis problemcan be formulated into a mixed integer nonlinear programming
    (MINLP) model. In this article, a generalized statespace model based on typical MEN is
    established and verified in two cases. A new asymmetrical operator and costindex are also
    adopted to speed up the solution process. The results demonstrate the efficiency of the
    proposedapproach.
    Study on Synthesis, Characterization and Catalytic Activity of Polystyrene-supported Mo (Ⅵ
    ) Complex in Epoxidation of Cyclohexene
    ZHANG Yadong, GAO Xiaolei, CHEN Xia, WANG Chaojin, JIANG Denggao
    2003, 11(3):  318-325. 
    Abstract ( 707 )   PDF (2941KB) ( 277 )  
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    Molybdenum (Ⅵ) complex, namely molybdenum dioxobis(2,4-pentanedione) [MoO2(acac)2] used
    asepoxidation catalyst species, was synthesized and characterized by elemental analysis and
    infrared spectrum.Polystyrene-supported molybdenum dioxobis(2,4-pentanedione) [MoO2(acac)2]
    for synthesis of epoxycyclohexanewas prepared by phase transfer catalysis method. Effects
    of various factors in synthesis of epoxycyclohexane by re-action of cyclohexene and t-BuOOH
    in the atmosphere of nitrogen catalyzed by polystyrene-supported MoO2 (acac)2were also
    investigated. Under the following conditions, n(cyclohexene):n(t-BuOOH)=3.5:1 (based on
    0.1 mol of t-BuOOH), volume of solvent ~10 ml, reaction temperature ~80℃, reaction time
    ~60 min, and mass of molybdenumin the catalyst ~ 2.30 × 10-3 g, the yield of
    epoxycyclohexane on the basis of t-BuOOH is over 99.5%, and thepurity of epoxycyclohexane
    is about 99.9% by gas chromatogram(GC) analysis.
    REVIEWS
    Preparation, Properties and Application of Polymeric Organic-Inorganic Nanocomposites
    REN jie, LIU Yan, TANG Xiaozhen
    2003, 11(3):  326-333. 
    Abstract ( 782 )   PDF (3497KB) ( 253 )  
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    Six preparation methods for polymeric organic-inorganic nanocomposites and their respective
    mecha-nisms and features are reviewed. The extraordinary properties of polymeric organic-
    inorganic nanocomposites arediscussed,and their potential applications are evaluated.
    CHEMICAL ENGINEERING DATA
    Solid-Liquid Equilibrium of Terephthalic Acid in Several Solvents
    MA Peisheng, CHEN Mingming
    2003, 11(3):  334-337. 
    Abstract ( 690 )   PDF (1190KB) ( 305 )  
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    Terephthalic acid(PTA) is practically one of the main materials of polyester. Its
    corresponding solid-liquid equilibrium data will provide essential support for industry
    design and further theoretical studies. In this work,solid-liquid equilibriums of
    terephthalic acid in four solvents, N,N-dimethylformamide, N,N-
    dimethylacetamide,dimethylsulphoxide and N-methyl-2-ketopyrrolidene, were determined in the
    temperature range from 293.15 K to364.6 K by dynamic method. All these data were regressed
    by λh model, Wilson model and NRTL model, averageabsolute relative deviations of which are
    1.25%, 15.02% and 7.22% respectively. It indicates that λh model is mostsuitable for
    description of the solid-liquid equilibrium containing PTA.
    RESEARCH NOTES
    Preparation of Ethylene Glycol Monoethyl Ether Acetate Using a Tubular Reactor
    CAI Zhenyun, LU Zuguo, LI Xiaobo
    2003, 11(3):  338-340. 
    Abstract ( 748 )   PDF (961KB) ( 253 )  
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    Ethylene glycol monoethyl ether acetate (EGEA), an excellent solvent, is prepared with
    ethylene oxide(EO) and ethyl acetate (EA) in a tubular reactor under suitable reaction
    condition. The single circulation yield canreach 81%. This technology is not only safe but
    also makes it possible to continuously produce EGEA in industry,with low content of high
    boiling point by-products.
    Separation and Purification of Tobacco Peroxidase I from Nicotiana Tobaccum
    XIA Bingle, LIU Qingliang, LI Minli, XU Xiaolong, SHI Chunhua, XIE Yongshu
    2003, 11(3):  341-343. 
    Abstract ( 639 )   PDF (1012KB) ( 230 )  
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    A new isoenzyme of tobacco peroxidase(TOP) I was purified from tobacco (K326) by using
    acetonepowder, ammonium sulfate precipitation and column chromatography on DEAE-52
    cellulose Sephadex G-75 andDEAE-Sephadex A-50. It is an iron-protein containing
    haemachrome, whose molecular weight is 21888.5 and theisoelectric point is 3.5. The optimum
    pH value and temperature of this enzyme is 6.0 and 45℃ respectively. Theenzyme is stable
    in the pH range from 3.0 to 10.0 and has a favorable thermostability.
    Mechanism of Coalescence Demulsification with Microfiltration Membrane
    ZOU Caisong, LUO Guangsheng, SUN Yong, DAI Youyuan
    2003, 11(3):  344-347. 
    Abstract ( 697 )   PDF (1140KB) ( 313 )  
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    A study on the membrane coalescence demulsification was carried out with four working
    systems ofwater/n-butyl alcohol, water/n-octanol, water/30%TBP(in kerosene) and
    water/kerosene. The membranes madeof polytetrafluoroethylene (PTFE) with 1.0μm pore size
    were used. The results indicated that the excellent demul-sification efficiency for
    emulsions with various oil contents was obtained. A conductivity probe was used to studythe
    demulsification mechanism. An electrode probe was designed and used to determine the oil
    content near themembrane surface. The obtained data showed that the oil content in the
    permeated stream was much higher thanthat in the feed emulsion. A physical mechanism to
    explain the membrane demulsification was put forward.
    Electrochemical Deposition of Ni-W Gradient Deposit and Its Structural Characterization
    WANG Hongzhi, YAO Suwei, ZHANG Weiguo
    2003, 11(3):  348-351. 
    Abstract ( 934 )   PDF (1167KB) ( 209 )  
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    The Ni-W gradient deposit with nano-structure was prepared by an electrochemical deposition
    method.X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDXA) indicate that
    the crystallite size of the depositdecreases from 10.3nm to 1.5nm and the crystal grating
    aberrance increases with the increase of W content in thegrowing direction of the deposit.
    The structure of deposit changes from crystalline to amorphous stepwise withassociated
    increase of crystal grating aberrance, and presents gradient distribution. These show that
    the deposit isgradient with nano-structure.
    Catalytic Wet Air Oxidation of o-Chlorophenol in Wastewater
    XU Xinhua, WANG Dahui
    2003, 11(3):  352-354. 
    Abstract ( 585 )   PDF (1012KB) ( 296 )  
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    Catalytic wet air oxidation (CWAO) was investigated in laboratory-scale experiments for the
    treatmentof o-chlorophenol in wastewater. Experimental results showed that wet air
    oxidation (WAO) process in the absence ofcatalyst was also effective for o-chlorophenol in
    wastewater treatment. Up to 80% of the initial CODCr was removedby wet air oxidation at 270
    ℃ with twice amount of the required stoichiometric oxygen supply. At temperatureof 150℃,
    the removal rate of CODCr was only 30%. Fe2(SO4)3, CuSO4, Cu(NO3)2 and MnSO4 exhibited
    highcatalytic activity. Higher removal rate of CODCr was obtained by CWAO. More than 96% of
    the initial CODCrwas removed at 270℃ and 84.6%-93.6% of the initial CODCr was removed at
    150℃. Mixed catalysts had bettercatalytic activity for the degradation of o-chlorophenol
    in wastewater.
    Kinetic Model of Resin-Catalyzed Decomposition of Acetone Cyanohydrin in Organic Solvent
    ZHANG Tingzhou, YANG Lirong, ZHU Ziqiang, WU Jianping
    2003, 11(3):  355-357. 
    Abstract ( 1027 )   PDF (1017KB) ( 210 )  
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    Decomposition of acetone cyanohydrin is the first-step reaction for preparing (S)-α-cyano
    -3-phenoxybenzyl alcohol (CPBA) by the one-pot method in organic media. Considering the
    compatibility of bio-catalysts with chemical catalysts and the successive operation in the
    bioreactor, anion exchange resin (D301) wasused as catalyst for this reaction. External
    diffusion limitation was excluded by raising rotational speed to higherthan 190r@min-1 in
    both solvents. Internal diffusion limitation was verified to be insignificant in this
    reactionsystem. The effect of acetone cyanohydrin concentration on the reaction was also
    investigated. An intrinsic kineticmodel was proposed when the mass transfer limitation was
    excluded, and the average deviation of the model is10.5%.
    Chaos Transfer in Fluidized Beds Accompanied with Biomass Pyrolysis
    TANG Songtao, LI Dingkai, LÜ, Zian, SHEN Youting
    2003, 11(3):  358-361. 
    Abstract ( 938 )   PDF (1233KB) ( 293 )  
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    Experiments of biomass pyrolysis were carried out in a fluidized bed, and dynamic signals
    of pressure andtemperature were recorded. Correlation dimension was employed to
    characterize the chaotic behavior of pressure andtemperature signals. Both pressure and
    temperature signals exhibit chaotic behavior, and the chaotic behavior oftemperature
    signals is always weaker than that of pressure signals. Chaos transfer theory was advanced
    to explain theabove phenomena. The discussion on the algorithm of the correlation dimension
    shows that the distance definitionbased on rhombic neighborhood is a better choice than the
    traditional one based on spherical neighborhood. Theformer provides a satisfactory result
    in a much shorter time.



    Comparison of the Reynolds-averaged Turbulence Models on Single Phase Flow Simulation in
    Agitated Extraction Columns
    YOU Xueyi, H.J.Bart
    2003, 11(3):  362-366. 
    Abstract ( 882 )   PDF (1656KB) ( 292 )  
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    The flow field of liquid phase (water) of agitated extraction columns is simulated with the
    help ofcomputational fluid dynamics (CFD). Four kinds of Reynolds-averaged turbulence
    models, i.e. the standard k-εmodel, the RNG (renormalization group) k-ε model, the
    realizable k-ε model and the Reynolds stress model, arecompared in detail in order to
    judge which is the best model in terms of the accuracy, less CPU time and memoryrequired.
    The performance of the realizable k-ε model is obviously improved by reducing the model
    constant fromc2 = 1.90 to c2 = 1.61. It is concluded that the improved realizable k-ε
    model is the optimal model.
    Separation of Quercentin by Pre-dispersed Solvent Extraction
    HU Wei, SUN Ying, YE Ruqiang, WU Shusen, LIU Honglai
    2003, 11(3):  367-370. 
    Abstract ( 707 )   PDF (1198KB) ( 309 )  
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    Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted
    solution. Theinfluences of temperature, phase volume ratio (PVR), concentration of sodium
    Dodecyl benzene sulphonate andpH value etc. on the extraction efficiency were examined. It
    is found that, compared with traditional extractiontechniques under the same condition, a
    higher extraction productivity can be obtained by PDSE. The stabilityof colloidal liquid
    aphrons plays an important role in this process. In a certain scope, the extraction
    efficiencyincreases with PVR. Excessive amount of solvent is not much helpful. A new
    analytical method by using ultravioletspectrometer to determine the concentration of
    quercentin is established.