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Table of Content
05 May 2007, Volume 58 Issue 5
    热力学
    Molecular dynamics simulation of properties of solvent in gel network
    FENG Jian;HUANG Yongmin;LIU Honglai
    2007, 58(5):  1073-1076. 
    Abstract ( 693 )   PDF (670KB) ( 329 )  
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    Three kinds of gel networks with different structures were studied via molecular dynamics(MD)simulation.Both the pressure and the self-diffusion coefficient of the solvent were investigated in detail,as well as the density distribution of the solvent in different regions of gel networks.The simulated results showed that the heterogeneity of gel structures had little influence on the properties of the solvent in the studied gel networks,although there was considerable difference between pure solvent and the solvent in the gel networks.

    Determination and correlation of solubilities of clove oil components in supercritical carbon dioxide
    GUAN Wenqiang;LI Shufen;HOU Caixia;YAN Ruixiang;MA Jun
    2007, 58(5):  1077-1081. 
    Abstract ( 1111 )   PDF (466KB) ( 645 )  
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    The solubilities of eugenol, eugenol acetate and β-caryophyllene, which are the main components in clove oil, in supercritical CO2 were separately determined at the temperature range from 40℃ to 60℃ and pressure from 10 MPa to 30 MPa.The results showed that the solubilities of these components increased with increasing pressure or decreasing temperature.The solubility of β-caryophyllene was higher than those of eugenol and eugenol acetate at the same temperature and pressure.The solubilities of eugenol in SC-CO2 were between 0.0002 and 0.0580 (mole fraction).The solubilities of β-caryophyllene in SC-CO2 were between 0.00034 and 0.07096 (mole fraction).The solubilities of eugenol acetate in SC-CO2 were between 0.00018 and 0.07030 (mole fraction).The solubility data of the main components of clove oil in SC-CO2 were correlated with the Chrastil equation and improved Chrastil equations presented by Adachi and del Valle.The values of average-absolute-relative-deviation(AARD) for eugenol solubility correlation were 4.92%,4.47%,5.19% respectively.The values of AARD for eugenol acetate solubility correlation were 3.69%,2.91%,3.24% respectively. The values of AARD for β-caryophyllene solubility correlation were 4.77%,4.41%,4.21% respectively.
    Determination and correlation of solubilities of catechol
    XIA Xianwei;JIANG Denggao
    2007, 58(5):  1082-1085. 
    Abstract ( 711 )   PDF (529KB) ( 297 )  
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    By using a laser monitoring technique,the solubilities of catechol in water, ethyl acetate, butyl acetate and 4-methyl-2-pentanone were determined by the synthesis method.A simplified equation was proposed to correlate the experimental data, and the solubility values calculated by the correlation equation showed good agreement with the experimental values.
    Binary isobaric vapor-liquid equilibrium of N-formylmorpholine with benzene
    XIONG Jieming;ZHANG Liping
    2007, 58(5):  1086-1090. 
    Abstract ( 830 )   PDF (907KB) ( 304 )  
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    The extraction of aromatics with N-formylmorpholine (NFM) has been widely used in petrochemical and coal tar industries.However, the vapor-liquid equilibrium (VLE) data of N-formylmorpholine-aromatics systems are very limited, and no isobaric VLE data can be found in literature.The VLE data of benzene-NFM system were determined by using an improved VLE equipment EC-2.The experimental VLE data were correlated with the thermodynamic models NRTL and UNIQUAC, and the corresponding binary interaction parameters for these two models were obtained.The results showed that the VLE data agreed well with the two models, and passed the thermodynamic consistency test of Herington.By comparison with these models from literature, it is found that these two models are more suitable for VLE prediction for NFM systems above 80℃.The VLE data and model parameters obtained are essential for the engineering design of N-formylmorpholine-aromatics distillation processes.
    传递现象
    Analysis of asymmetry of gas-phase flow field in volute cyclone
    SONG Jianfei;WEI Yaodong;SHI Mingxian
    2007, 58(5):  1091-1096. 
    Abstract ( 600 )   PDF (1308KB) ( 335 )  
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    The asymmetry characteristics of the gas-phase flow field in a volute cyclone were analyzed with software package FLUENT 6.1 and its asymmetry mechanism was investigated based on the simulated results.Because of the asymmetry of the inlet structure and the unstable characteristics of the swirl flow,the spinning center of the gas flow deviated from the geometrical center of the cyclone,which resulted in the asymmetry of the flow field and the change of the three dimensional velocity components.Based on the Rayleigh criterion,the unstable characteristics of the swirl flow in the cyclone were intrinsic.The instability decreased with increasing swirl number,which weakened the degree of asymmetry of flow field.The swirl number did not vary with inlet velocity,which indicated that the inlet velocity did not affect the asymmetry of flow field.However,the swirl number increased with increasing ratio of cyclone body cross section area to the inlet area KA and decreasing ratio of the internal diameter of the exit tube to the cyclone body diameter de,which weakened the degree of asymmetry of flow field.The degree of asymmetry could be evaluated by the tangential angular momentum.
    Numerical investigation on shell side support of longitudinal flow heat exchanger
    WANG Shuqi;HUANG Suyi
    2007, 58(5):  1097-1103. 
    Abstract ( 541 )   PDF (1807KB) ( 231 )  
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    A new type of staggered short rod support in the shell side of a longitudinal flow heat-exchanger was proposed.Numerical investigation was performed for short rod, short tube, square rod baffle supports and self-supports of wave-tube bundles and mixed tube bundles in the fully developed flow and heat transfer zone by using the turbulent model and hexahedron grid with the commercial software FLUENT.For each support the heat transfer,resistance, aggregative indicator -h/(LΔp)and the reliability for different values of support space (Ls=4.56, 9.13) and different Re(Re=2630,13150,26300,52600) were investigated.
    Experimental study on mass and heat recovery of a highly efficient multi-function heat pipe type adsorption ice making system
    LI Tingxian;WANG Ruzhu;WANG Liwei;LU Zisheng;CHEN Chuanjuan
    2007, 58(5):  1104-1109. 
    Abstract ( 704 )   PDF (1723KB) ( 227 )  
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    A multi-function heat pipe type adsorption ice maker, which uses activated carbon-CaCl2 as compound adsorbent and ammonia as refrigerant, was designed.For this test unit, the heating, cooling and heat recovery processes between two adsorbent beds were performed by multi-function heat pipes.The influence of recovery of mass and heat on the performance of adsorption ice maker was investigated.The experimental results showed improved recovery of mass and heat.The coefficient of performance (COP) was increased by 25.5 %, and the power consumption of boiler and the cooling capacity of cooler were reduced by about 13 % and 21 % respectively.When the mass recovery process was implemented before the heat recovery process, the mass recovery process with heating/cooling desorption/adsorption bed increased the rate of ice production obviously, which might help to increase COP and specific cooling power (SCP) by more than 15 % if compared with the conventional mass recovery process.The increase of SCP was higher than that of COP.Under the condition of different temperatures of cooling water, experiments showed that SCP was still high at a higher temperature of cooling water although the performance of adsorption ice maker dropped as temperature of cooling water became higher.At a cooling water temperature of 27℃ and an evaporating temperature of -18.9℃, SCP was still as high as 356.5 W·kg-1.
    Spectral element method for solving radiative heat transfer in semi-transparent media
    ZHAO Junming;LIU Linhua
    2007, 58(5):  1110-1114. 
    Abstract ( 572 )   PDF (741KB) ( 165 )  
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    Radiative transfer equation(RTE)in Cartesian coordinates can be considered as a special kind of convective-diffusive equation and is convection dominated.Numerical solution of the convection dominated problem often suffers from spurious oscillations.The spectral element method based on streamline upwind Petrov-Galerkin(SUPG)stabilization scheme was developed to solve multidimensional radiative heat transfer in semi-transparent media.Three test cases were taken as examples to verify the performance of the SUPG spectral element method for solving multi-dimensional radiative heat transfer in semi-transparent media.The SUPG spectral element method effectively diminished the spurious oscillations as compared with the Galerkin spectral element method.The distributions of radiative intensity and net wall heat flux were calculated and compared with the analytical results and data in references.By comparison,it was shown that the SUPG spectral element method developed in this paper had good accuracy in solving radiative heat transfer in semi-transparent media.
    Optimization approach for tube circuit of fin-and-tube heat exchanger based on genetic algorithm
    WU Zhigang;DING Guoliang;PU Hui;LONG Huifang
    2007, 58(5):  1115-1120. 
    Abstract ( 658 )   PDF (963KB) ( 311 )  
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    A novel tube circuit optimization approach for fin-and-tube heat exchanger was presented by developing a particular genetic coding method and genetic operators.A case study was performed on a practical heat exchanger.The optimization objective of the case was to obtain the shortest joint tube length of the tube circuit with the constraint conditions of satisfying the designed heat exchange capacity and the convenience of manufacture.Optimization result showed that the designed algorithm could converge within 5 h and the total joint tube length decreased by 25% after optimization.
    Effect of hydrophilic coating on airside performance of wavy fin-and-tube heat exchangers under dehumidifying conditions
    MA Xiaokui;DING Guoliang;ZHANG Yuanming
    2007, 58(5):  1121-1126. 
    Abstract ( 686 )   PDF (4838KB) ( 404 )  
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    The air side heat transfer and friction characteristics of wavy fin-and-tube heat exchangers with and without hydrophilic coating were studied under dehumidifying conditions experimentally.The effects of hydrophilic coating on air side performance were investigated.The results indicated that the hydrophilic coating could enhance heat transfer when condensed water droplets were too few to form water flow on the fin surface but weaken heat transfer when a large amount of condensed water droplets on the fin surface formed water flow.The pressure drop on the hydrophilic coating surface was lower than the corresponding uncoated surface.A maximum 44% reduction was observed.The proposed correlations of heat transfer coefficient and pressure drop for the heat exchanger with and without hydrophilic coating had a mean deviation of 9.9% and 8.2% from experimental data respectively and could cover 76.6% and 82.8% respectively of the experimental data within the deviation limit of ±15%.
    Local resistances of single-phase flow across abrupt expansion and contraction in small channels
    LI Zhuo;YU Jian;MA Chongfang
    2007, 58(5):  1127-1131. 
    Abstract ( 799 )   PDF (1278KB) ( 637 )  
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    Local resistances caused by abrupt expansion and contraction were experimentally investigated for the small channels with diameters from 0.330 mm to 0.580 mm by using a novel pressure measurement method of the tiny gaps on the channels.The experimental results showed that the pressure measurement method through the gaps was a feasible method for small channels.For laminar flow,the expansion loss coefficient was much lower and the contraction loss coefficient was much higher as compared with the experimental results of conventional channels,while for turbulent flow,the expansion and contraction loss coefficients were consistent with those of the conventional channels.
    Numerical simulation of flow and heat transfer during quenching process
    MING Pingjian;JIANG Renqiu
    2007, 58(5):  1132-1137. 
    Abstract ( 672 )   PDF (511KB) ( 236 )  
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    A simplified model based on multi-phase flow and heat transfer during the quenching process was developed.A set of equations of fluid flow and heat transfer were derived from two-phase fluid dynamics and fluid-solid conjugated heat transfer (CHT).User-defined functions of the commercial CFD software Fluent were designed for the numerical simulation of fluid flow and heat transfer during the quenching process according to the model.Some influence factors were analyzed and the results showed that the numerical results were consistent with the theoretical analysis.Finally numerical simulation was also done with a rectangular aluminum block, and the computed temperature history within the aluminum block was compared with the temperature history of measured data by using thermocouples in the literature.The error was below 15%.The present model is feasible and captures the major aspects of the quenching process.
    Effect of temperature dependent blood perfusion and metabolic heat generation on heat transfer problem in cryosurgery
    ZHAO Gang;LIU Zhifeng;GAO Dayong
    2007, 58(5):  1138-1144. 
    Abstract ( 583 )   PDF (26254KB) ( 271 )  
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    The formulas describing the dependence of blood perfusion rate on temperature were set up for the whole temperature range from hypothermia to hyperthermia.The influence of the temperature dependent blood perfusion rate and metabolic heat generation on the transient thermal field and thermal gradient field were studied by using finite element analysis.The enthalpy method was used to solve the thermophysical nonlinear and multidimensional phase change problem in cryosurgery of the target tissue, and the tissue was treated as non-ideal materials freezing over a temperature range.Theoretical simulation indicated that without full consideration of the thermal dependence of blood perfusion rate and metabolic heat, the transient temperature of the typical point or the temperature along the typical path inside the tissue would both be overestimated, the temperature difference even reached about 5℃;the thermal gradients of the typical points inside the tissue or on the cryoprobe surface were also overestimated.Besides, the thermal gradient of the typical point on the cryoprobe surface was much larger than that of the point inside the tissue, and this might have certain relation to the often appearing cracks or ruptures inside the tissue closely tied to the cryoprobe surface during cryosurgical process.This study suggested that the thermal dependence of blood perfusion rate and metabolic heat generation should be fully incorporated into the analysis of the heat transfer problem in cryosurgery and should be fully considered for the design/optimization of the cryosurgical procedure and cryoprobe.
    Mass transfer kinetics of PVP across oil-water interface by using micro visualization technique
    XU Junhui;CHEN Jinfang;CHEN Zhong
    2007, 58(5):  1145-1149. 
    Abstract ( 552 )   PDF (1170KB) ( 222 )  
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    A visualization system based on microscopy,photoelectric imaging analysis and digital processing was developed to investigate the micrometer-level mass transfer process of polyvinylpyrrolidone(PVP)across the interface of dichloromethane-water.The concentration-gray scale standard curves were obtained by measuring the gray scales of the images of 10 PVP dichloromethane solutions with different concentrations.The concentrations of PVP corresponding to different times were determined by measuring the gray scales of the images of PVP dichloromethane solutions at the corresponding times.The mass transfer kinetics curve of PVP across the interface of dichloromethane-water was then obtained.In addition,the evolution of flow field in the dichloromethane phase near the interface was observed and analyzed via the visualization system.
    Performance of novel 13X zeolite based refrigerant compound adsorbent
    ZHAO Huizhong;ZHANG Min;LIU Zhenyan;MA Xiaodong;ZHANG Bo
    2007, 58(5):  1150-1154. 
    Abstract ( 669 )   PDF (758KB) ( 256 )  
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    A series of compound adsorbents with zeolite as the main component were prepared, and the adsorption and desorption performance of these adsorbents were measured.To get the expected compound adsorbent, the filling densities and the forming characteristics of the compound adsorbent were tested.The study showed that the performance of compound adsorbent E was better than that of the original 13X zeolite.The filling densities decreased remarkably with the silica sol content between 0—7%.A solar cooling tube was made from the compound adsorbent E,its coefficient of performance (COP) was about 0.24—0.28.
    多相流和计算流体力学
    Cell model approach to motion of bubbles in swarm
    MAO Zaisha
    2007, 58(5):  1155-1162. 
    Abstract ( 695 )   PDF (1352KB) ( 301 )  
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    To account for the interaction between bubbles in a swarm, cell models were applied to simulating numerically the bubble motion in a swarm of deformable gas bubbles with a Reynolds number of 50.Simulations were based on the full Navier-Stokes equation of liquid flow in a spherical cell.The stream function and vorticity of the axi-symmetrical flow field were solved in a boundary-fitted orthogonal reference frame.Numerical results suggested significant effects of gas holdup on the drag coefficient and deformation of bubbles in a swarm, but the drag coefficient predicted by the model was much higher than that from theoretical equations based on spherical bubbles in creeping flow.The cell model with zero shear stress as the outer cell boundary condition seemed to behave better than that with zero vorticity condition.It is suggested that the cell model is a potentially reliable approach to resolve the bubble behavior in a dense swarm.
    Eulerian-Lagrangian simulation of hydrodynamics of gas-solid flows in downer
    ZHAO Yongzhi;CHENG Yi;DING Yulong;JIN Yong
    2007, 58(5):  1163-1171. 
    Abstract ( 792 )   PDF (4574KB) ( 240 )  
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    The gas-solid flows in two-dimensional downer were simulated by using a CFD-DEM method.The simulation results showed the typical flow structures in the dower.Along the flow direction, there existed the entrance region, the transition region, and the (fully) developed region, in which the clusters started to form in the transition region instead of the entrance region with a denser particle concentration.With the flow development, the clusters grew in size and increased in number.Particles inside each cluster were loosely collected, flowing in the same direction as the bulk flow.The lateral distribution of solids fraction in the fully developed region was non-uniform, with a denser ring near the wall.These results agreed well with the experimental results reported in the literature.The influence of the physical properties of the wall and particles on the global solids flow structure was investigated.The ideally elastic particles with no friction during collisions dispersed very rapidly and uniformly at the entrance.The influence of the collision parameters between particles on the lateral flow structure was not obvious in this work.
    Chaotic recurrence characteristics analysis of conductance fluctuating signal of gas/liquid two-phase flow
    JIN Ningde;ZHENG Guibo;CHEN Wanpeng
    2007, 58(5):  1172-1179. 
    Abstract ( 600 )   PDF (2967KB) ( 327 )  
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    This paper investigated the influence of phase space embedding parameters,which are embedding dimension,time delay and threshold,on the recurrence analysis based on the classical Lorenz chaotic equation and Logistic mapping.The study results showed that the recurrence analysis was not significantly dependent on the embedding parameters,and the variations of embedding dimension and time delay only led to changes of recurrence rate and did not change the texture of recurrence plot.In the same way,the threshold could directly affect the amount of recurrence points and did not change the texture of recurrence plot.Finally the recurrence analysis method was used to characterize flow patterns of gas-liquid two-phase flow in a vertical upward pipe,the characterization result showed that the recurrence plot could well reflect the evolution characteristics of flow pattern,and the recurrence characteristics quantities were sensitive to the variations of superficial gas velocity and provided the useful characteristics mining quantities for flow pattern identification of gas/liquid two-phase flow.
    Effects of geometrical size on flow characteristics of jet in sonic oscillator
    HU Dapeng;CHEN Zuzhi;DAI Yuqiang;CHEN Shengtao
    2007, 58(5):  1180-1184. 
    Abstract ( 584 )   PDF (407KB) ( 217 )  
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    The flow characteristics of the jet in a sonic oscillator are mainly determined by its geometrical size. The effects of geometrical size were studied by experiments and numerical simulation.The conclusions were as follows:(1)The switch cycle of the jet was proportional to the controlling tube length and approximately equal to the time that sonic wave passed through the controlling tube;(2)When the controlling tube was too long, too wide or too narrow,the jet would not oscillate.The range of the controlling tube length which caused jet oscillation became smaller with narrowing controlling tube;(3)If the wall-offset or wedge-distance was too small,the jet could not attach the wall.In addition, their effects were correlative.When the wedge became nearer to the nozzle, the smallest wall-offset that could induce jet oscillation increased.
    Numerical simulation and structure optimization of liquid-solid distributor
    WANG Yiping;ZHOU Cuiyan;ZHU Li;LIU Junjie;DENG Lin
    2007, 58(5):  1185-1190. 
    Abstract ( 564 )   PDF (3971KB) ( 270 )  
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    How to uniformly distribute the liquid-solid two-phase flow is a difficulty which restricts the development of the liquid-solid fluidized bed.An Eulerian multiphase model incorporating the kinetic theory for solid particles was used to simulate the liquid-solid two-phase flow.The hydrodynamics in the lower vessel in a two-dimensional liquid-solid fluidized bed heat exchanger was simulated with the CFD method.The structural parameters of the liquid-solid distributor was optimized by simulation methods.The simulation results were in relatively good agreement with the experiments.The results indicated that when the angle of the V baffle was less than slide angle,the hole ratio of perforated plate was about 35% and the hole diameter was about 12 mm,the unevenness of solids volume fraction in the lower vessel was the least.
    Flow characteristics and Shannon entropy analysis of dense-phase pneumatic conveying of pulverized coal under high pressure
    LIANG Cai;CHEN Xiaoping;PU Wenhao;LU Peng;FAN Chunlei;ZHAO Changsui
    2007, 58(5):  1191-1196. 
    Abstract ( 757 )   PDF (472KB) ( 288 )  
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    Experiments of dense-phase pneumatic conveying of pulverized coal using nitrogen were carried out in an experimental test facility with the conveying pressure up to 4 MPa and the solid-gas ratio up to 450 kg·m-3.The influences of conveying differential pressure,gas volume flow rate and superficial velocity on the solid-gas ratio were investigated.The Shannon entropy analysis of pressure fluctuation time series was developed to reveal the flow characteristics.Through the investigation on the distribution of Shannon entropy in different conditions,the flow stability and evolutional tendency of Shannon entropy in different regimes and regime transition processes were discovered.The relationship between Shannon entropy and flow regimes was also established.The results indicated that solid gas ratio and Shannon entropy increased with increasing conveying differential pressure.Shannon entropy was different for different flow regimes,and was able to identify the flow regimes.Shannon entropy analysis is a feasible approach to researching the characteristics of flow regimes and flow regime transitions in dense-phase pneumatic conveying under high pressure.
    催化、动力学与反应器
    Experimental and kinetic studies on methane replacement from methane hydrate formed in SDS system by using pressurized CO2
    LI Zunzhao;GUO Xuqiang;CHEN Guangjin;WANG Jinbao;YANG Lanying;WANG Ting
    2007, 58(5):  1197-1203. 
    Abstract ( 659 )   PDF (839KB) ( 363 )  
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    The process and kinetics of CH4 replacement from CH4 hydrate formed in sodium dodecyl sulfate(SDS) system by using pressurized CO2 was observed with a self-designed device at temperatures of 271.2, 273.2 and 276.0 K and at pressures of 2.8, 3.25 MPa.Experimental data showed that the decomposition rate of CH4 hydrate was faster in the first 50 hours than the later time.Above ice point, the decomposition rate of CH4 hydrate was faster than that below ice point.Based on the rate data, kinetic models were developed for CH4 hydrate decomposition and CO2 hydrate formation.In the process of CH4-CO2 replacement in the hydrate, the activation energies were,calculated 28.81 kJ·mol-1 for CH4 hydrate decomposition and 68.40 kJ·mol-1 for CO2 hydrate formation respectively.The analysis of the experimental data and activation energies indicated that CH4 hydrate decomposition was probably dominated by re-arrangement of water molecules in the hydrate and CO2 hydrate formation was probably dominated by diffusion of CO2 in the hydrate.
    New model-free method based approach to mechanism of limestone decomposition
    ZHANG Baosheng;LIU Jianzhong;ZHOU Junhu;CEN Kefa
    2007, 58(5):  1204-1209. 
    Abstract ( 599 )   PDF (423KB) ( 293 )  
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    A new approach based on the model-free method was proposed to deduce the most probable mechanism function.Firstly, the kinetic models were screened in accordance with the reaction process.Secondly,the Popescu method was adopted to do further screening by virtue of linear correlation coefficient of regression calculation.Finally, the apparent activation energy that was obtained by a combination of the differential method based on single-heating rate and the equi-conversion method based on the multiple-heating rate methods was used to confirm the most probable mechanism function.This approach could avoid the kinetic compensation effect, and in the course of calculation almost no hypothesis or approximation was made and the error caused by differential calculus could be reduced on account of the multiple-heating rate method.The mechanism functions could be easily distinguished when the apparent activation energy other than the linear correlation coefficient was served as the criterion.Thermogravimetry was used to analyze the decomposition of three kinds of limestone,and the result indicated that the shrinking cylinder mechanism with controlling surface reaction rate was the most probable kinetic function.
    Pyrolysis and pyrolysis kinetics of coconut shell, coconut shell residue and de-ashed coconut shell residue
    YAO Boyuan;DOU Zhifeng;HUANG Guangmin;LIU Rencheng
    2007, 58(5):  1210-1214. 
    Abstract ( 841 )   PDF (767KB) ( 445 )  
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    The pyrolysis of coconut shell, coconut shell residue and de-ashed coconut shell residue was studied with the thermogravimetric technique, and the pyrolysis kinetics models were established.It was found that for coconut shell residue and de-ashed coconut shell residue, pyrolysis mainly occurred between 280—370℃, and there was only a single peak in their DTG curves.But in the case of raw coconut shell, two stages of 230—300℃ and 300—350℃, were involved in the pyrolysis process, which resulted in two peaks in the DTG curve.Apparent activation energies for the pyrolysis of these three materials were estimated, and the difference of apparent activation energies in the low temperature range was more evident than in the high temperature range and the highest reaction rate appeared in the high temperature stage.When used for making activated carbon, coconut shell residue and de-ashed coconut shell residue have more advantages than coconut shell.The pyrolysis temperature is in a narrow range.The pyrolysis process is easy to control and is noted for energy saving.
    Synthesis and characterization of multi-micronutrient fertilizer ammonium cupric phosphate via solid state reaction
    WU Hongte;LIAO Sen;WU Wenwei;LIAO Min;CAO Hong
    2007, 58(5):  1215-1219. 
    Abstract ( 694 )   PDF (417KB) ( 335 )  
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    A novel method for the synthesis of multi-micronutrient fertilizer ammonium cupric phosphate was studied,and the target product was obtained successfully with CuSO4·5H2O and(NH4)3PO4·3H2O as raw materials and PEG-400 as template via the one step low heat solid state reaction.SNR(signal-to-noise)calculated with XRD data of the products was used as testing indicators,and uniform experimental design as well as data mining technology were used in the test.The synthesis tests were carried out,and were guided by the results of data mining technology.The test results indicated that the product synthesized with the optimal technical condition was NH4CuPO4 ·H2O with size of 51nm.For the products are all fertilizer,so it is obvious that a mixture of the synthesis products can be used as fertilizer without any separation.The synthesis process is not only simple but also without any waste water,so the synthesis is a much more potential industrial process when it is compared with those syntheses in liquid state in view of the process itself or environment protection.
    分离工程
    Treatment of wastewater from benzyl alcohol production with resin adsorption
    CHEN Yiliang;PAN Bingcai;ZHANG Quanxing
    2007, 58(5):  1220-1224. 
    Abstract ( 800 )   PDF (427KB) ( 678 )  
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    An adsorption process to treat the wastewater from benzyl alcohol production with hyper-crosslinked macropore resin was studied.The factors, including pH, temperature, flow rate, desorption reagent, etc.that influenced the adsorption-desorption process were investigated.Based on the investigation, the process parameters for the treatment were optimized.The results showed the hyper-crosslinked macropore resin JX-101 exhibited excellent adsorption-desorption performance for benzyl alcohol.Through the fixed-bed adsorption process under optimal conditions, the concentration of benzyl alcohol in the wastewater was reduced from 14000 mg·L-1 to 25 mg·L-1 and COD was reduced from 34000 mg·L-1 to less than 100 mg·L-1.The removal rate of benzyl alcohol and COD was over 99%,and the effluent quality met National Discharge StandardⅠ.Furthermore, benzyl alcohol in the wastewater could be recovered, with purity of 85%.The process is convenient and could be steadily run, which provides the experimental basis for the treatment and resource reuse of benzyl alcohol production wastewater.
    Adsorption of phosphate by Fe(Ⅲ) immobilized on collagen fiber
    DING Yun; LIAO Xuepin;SHI Bi
    2007, 58(5):  1225-1231. 
    Abstract ( 684 )   PDF (1324KB) ( 223 )  
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    A novel adsorbent for the removal of phosphate in aqueous solution was prepared by immobilizing Fe(Ⅲ) onto collagen fiber (FeICF).The characteristics of phosphate adsorption on FeICF was investigated.The equilibrium adsorption capacities of FeICF for phosphate was 32.69 mg P·g-1 at 303 K when the initial concentration of phosphate was equal to 62.0 mg P·L-1.Maximum phosphate adsorption was observed in the pH range of 3.0—6.0, which implied that the single charged species (H2PO-4) favored the adsorption of phosphate on FeICF.The adsorption isotherm of phosphate on FeICF could be described by the Langmuir equation, and the adsorption capacity increased with increasing temperature.The adsorption kinetics of phosphate on FeICF could be well-described by the pseudo-second-order rate model.The co-existing anions such as Cl-, NO-3, SO2-4 and CO2-3 in the solution had no effect on the adsorption of phosphate on FeICF.
    Interfacial area on valve trays
    LIANG Yinchun;ZHOU Zheng;ZHANG Zhibing
    2007, 58(5):  1232-1237. 
    Abstract ( 701 )   PDF (711KB) ( 400 )  
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    The vapor-liquid contact and interfacial area on the valve tray were investigated on the basis of the mechanism of bubble deformation and breakage in the turbulent liquid.A mathematical model was proposed to compute the interfacial area on the valve tray.This model was capable of comparing the effects of the different valve configurations on the interfacial area.Based on the study,a new type valve,called guided rhombic valve(GRV),was designed and tested on a test rig with a column inner diameter of 1000 mm.The results showed that the gas-liquid interfacial area of GRV could be remarkably increased.
    Preparation and permeation characteristics of novel PVA/APTEOS hybrid membranes
    ZHANG Qiugen;CHEN Yu;CHEN Jianhua;LIU Qinglin
    2007, 58(5):  1238-1243. 
    Abstract ( 870 )   PDF (567KB) ( 362 )  
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    Novel organic-inorganic hybrid membranes were prepared through sol-gel reaction of poly(vinyl alcohol)(PVA)with γ-aminopropyl-triethoxysilane(APTEOS).The resulting membranes were characterized with Fourier transform infrared spectroscopy and wide-angle X-ray diffraction.The swelling degree of PVA and PVA/APTEOS hybrid membranes in water/ethanol mixture was determined.The pervaporation performance was investigated by separation of water/ethanol mixture at 50℃.The effect of APTEOS content on the pervaporation performance was studied.The decrease in swelling degree with increasing APTEOS content was due to the formation of hydrogen and covalent bonds in the membrane matrix.The crystalline region of PVA decreased with increasing APTEOS content.The separation factor for water increased,and then decreased when APTEOS content was more than 5.0%(mass).The hybrid membrane containing 5.0%(mass) APTEOS exhibited the highest separation factor.However the permeation rate increased remarkably with increasing APTEOS content.The trade-off relation of the PVA membrane was solved,and the PVA/APTEOS hybrid membranes showed high pervaporation properties.
    Adsorption of ligand on recorded lipase polymers in organic phase
    SONG Xijin;XUAN Feng;WANG Jie;GONG Wei
    2007, 58(5):  1244-1247. 
    Abstract ( 620 )   PDF (372KB) ( 215 )  
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    Lipase and lauric acid were added into a copolymer system, which contained PEG400-dimethacrylate, trimethylolpropane trimethacrylate, and a surface-active agent.The polymerization was initiated by ultraviolet irradiation.Then recorded lipase polymers (RLP) of locking lipase conformation were obtained after lauric acid was extracted by a neat organic solvent.The adsorption of RLP in the lauric acid solution was studied.The adsorption isothermal curves were measured at temperature 30—50℃.The results indicated that RLPs adsorption capacity was far stronger than blank carriers and immobilized lipase polymers (ILP)s,about 8.7 and 3.9 times respectively.The adsorption process followed the Langmuir and Freundlich isothermal adsorption equations.
    Simulation method of batch extractive distillation
    FANG Jing;Lǔ Jianhua;LI Chunli;LIU Jidong
    2007, 58(5):  1248-1252. 
    Abstract ( 1120 )   PDF (374KB) ( 607 )  
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    A quasi-steady-state model for batch extractive distillation was provided.This shortcut model can be used to simulate the temperature of all trays in batch extractive distillation, the composition concentration of the still and the top of the distillation column.The experimental results were in good agreement with those from the model.The results proved that the model had such advantages as high precision and fast calculation.
    Phase-separation behavior for cloud point and application of non-ionic surfactant C12E10
    HUANG Yan;QIN Wei;LIU He;HUO Xiaoping;DAI Youyuan
    2007, 58(5):  1253-1258. 
    Abstract ( 962 )   PDF (546KB) ( 276 )  
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    Cloud point extraction (CPE) utilizing polyoxyethylene 10 lauryl ether (C12E10) as the surfactant was carried out to separate and concentrate di(2-ethyl hexyl) phosphoric acid (D2EHPA) in its dilute aqueous solution.The CPE process was facilitated by decreasing the cloud point (CP) temperature of the solution with sodium sulfate.The influence of C12E10 concentration, settling temperature, pH value, and Ni2+ in the solution on the extraction efficiency (E) was studied.The results showed that extraction efficiency increased with the concentration of C12E10, temperature and pH value of the system.Trace Ni2+ in the solution has no obvious influence on extraction efficiency of D2EHPA when pH=7.00.Single-stage extraction efficiency larger than 85% has been obtained.
    Recovery of nickel ions from dilute solutions by electrodeionization process
    LU Huixia;Yan Bo;Wang Jianyou;FU Xueqi
    2007, 58(5):  1259-1261. 
    Abstract ( 669 )   PDF (372KB) ( 245 )  
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    The recovery of nickel ions and pure water production from dilute nickel-containing solution was achieved simultaneously only within one process by using electrodeionization(EDI)system.With a 55 mg·L-1 nickel ions feed solution,the outlet concentration of dilute product was below 0.05 mg·L-1,therefore the nickel rejection was higher than 99.9%,and the dilute product resistivity was in the range of 2.02—2.59 MΩ·cm while the concentration of nickel ions in the concentrate stream could reach as high as 1263 mg·L-1.The feasibility of the EDI operation for the recovery of heavy metal ions together with pure water production from dilute industrial heavy metal wastewater was demonstrated in this study,cleaner production and closed circuit circulation can be realized in some industries such as electroplating.
    过程系统工程
    Multi-objective particle swarm optimization approach to solution of fed-batch bioreactor dynamic multi-objective optimization
    HE Yijun;YU Huanjun;CHENG Biao;CHEN Dezhao
    2007, 58(5):  1262-1270. 
    Abstract ( 1047 )   PDF (576KB) ( 510 )  
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    Multi-objective optimization is an important topic of process systems engineering.Through simply converting to a single goal,it often fails to reflect the more complex relationship between goals,and it is not conductive to effective decision-making at any time on demand.Swarm intelligence based particle swarm optimization(PSO)algorithm has good global optimization performance and can be easily implemented.To make it suitable for multi-objective optimization,PSO should be further rebuilt.Firstly,the concept of Pareto dominance was used to evaluate the fitness of particles,and two kinds of operation for determining the local and global optimal point respectively were designed.Secondly,velocity update strategy,utilizing all particles’ local best information,was used to enhance the ability of global convergence.Thirdly,an external archive technique was set up,and through calculating the degree of dispersion,an appropriate update strategy was adopted to uniformly approximate the Pareto optimal solution set step-by-step.Finally,multi-objective particle swarm optimization(MOPSO)was proposed,and it was applied to dynamic multi-objective optimization of fed-batch bioreactor,the satisfactory solution was obtained.According to the obtained pareto optimal solution set,the relationship between goals could be analyzed further,which could contribute to rational and effective decision-making.Compared with NSGA-Ⅱ,MOPSO showed better performance.
    生物化学工程与技术
    Synthesis and characterization of novel amino acid-based dendritic displacers
    SHI Qinghong;YANG Jie;SU Liang;SUN Yan
    2007, 58(5):  1271-1276. 
    Abstract ( 784 )   PDF (467KB) ( 279 )  
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    Novel dendritic displacers, Phe-D and Leu-D, with L-lysine as the dendritic branch and phenylalanine or leucine as the branching agent were synthesized by the solid-phase peptide coupling method on 1% cross-linked polystyrene bead functionalized with Fmoc-phenylalanine.The parameters in the steric-mass action (SMA) model for the novel displacers and their displacement performance were determined by chromatographic experiments, adsorption equilibrium and batch displacement experiments, and were compared with a typical displacer, N-α-benzoyl-L-arginine ethyl ester (BAEE).Based on the SMA model parameters, affinity ranking plots of the displacers and proteins were obtained.The results showed that the dynamic affinities of the displacers reduced with an increase of the logarithm of the partition ratio of the displacer (lgΔ).At a lgΔ less than 0.845, BAEE exhibited the highest dynamic affinity.At lgΔ from 0.845 to 3.08, Phe-D had the strongest dynamic affinity to the stationary phase.The batch displacement data for cytochrome C and α-chymotrypsinogen A demonstrated that the novel displacers gave a higher percentage of protein displacement from SP Sepharose HP due to more primary amine groups in the displacer molecules.On the other hand, the percentage of protein displacement increased by 70% due to the introduction of a phenyl group, confirming the enhancement effect of aromatic groups on protein displacement.
    能源和环境工程
    Mathematic simulation of air flow field in air sparging
    ZHENG Yanmei;LI Xingang;HUANG Guoqiang
    2007, 58(5):  1277-1282. 
    Abstract ( 687 )   PDF (2615KB) ( 196 )  
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    Air sparging (AS) is an emerging remediation technique to remove petroleum contaminants from groundwater.The mathematic simulation of flow field is an important method to study the remediation process on-site during air sparging.A two-dimensional mathematical model of the non-steady state flow process was developed based on the AS momentum equation of saturation, relative permeability and capillary pressure.The equation was solved with the finite element method, and the distributions of saturation, velocity vectors and isobars were obtained.The results from simulation revealed that the distribution of air saturation varied with the operation time and the location of sparging well.The required time to form the steady fluid field was about 5 h.The radius of influence(ROI) was 9 m in this simulation condition.Multi-well sparging is recommended to increase the ROI, when remedying a wider area.
    Influence of co-pyrolysis and catalysis of biomass with waste tire on pyrolytic oil properties
    CAO Qing;LIU Gang;BAO Weiren;Lǔ Yongkang
    2007, 58(5):  1283-1289. 
    Abstract ( 749 )   PDF (500KB) ( 456 )  
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    The properties of the oil obtained by co-pyrolyzing a mixture of rice husk biomass and waste tire in a tubular fixed-bed with MCM-41 and SBA-15 as catalysts were investigated with gas chromatography, elemental analyzer, viscometer and calorimeter.The results showed that the yield and heating value of the pyrolytic oil increased and its viscosity and density decreased as the percent of waste tire in the mixture was increased.Through pyrolyzing the mixture with rice husk accounting for 60%(mass), the liquid yield and heating value of the pyrolytic oil reached 44.5%(mass) and 40 MJ·kg-1 (approaching that of diesel)respectively.The temperature could obviously affect the yield of the pyrolytic oil and limonene content in the oil,both of which reached a maximum at 500℃.The limonene content was lower than that of the weighted value obtained through individual pyrolysis and the oxygen content was higher than that of the weighted value through individual pyrolysis.Through co-pyrolyzing the mixture of rice husk and waste tire, it was found that synergetic effect and interaction might take place for some components.Catalysts such as MCM-41 and SBA-15 greatly reduce the viscosity and density of the oil.Comparing with MCM-41, SBA-15 showed better catalytic effect than MCM-41. Comparing with the diesel(0#), the viscosity and density of the pyrolytic oil were slightly higher than those of diesel.
    Adsorption performance and mechanism of binding of dye by protonated coke waste
    CUI Longzhe;WU Guiping;DENG Kejian
    2007, 58(5):  1290-1295. 
    Abstract ( 807 )   PDF (532KB) ( 392 )  
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    The protonated coke waste was used as a new type of biosorbent for the removal of anionic dye Reactive Red 4(RR4) and cationic dye Methylene Blue(MB).The uptake was significantly affected by the pH of the solution.The Langmuir isotherm was found to represent the sorption data of RR4 and MB well.The maximum adsorption capacities of RR4 and MB on the biosorbent were (25.8±0.4)mg·g-1 and (161.2±10.0)mg·g-1 at pH 2 and 7 respectively.To identify the binding sites in the biosorbent, the biosorbent was potentiometrically titrated, and the data was analyzed through nonlinear regression of the proton-binding model.As a result, sulfonate, phosphonate and amine sites were present in the biosorbent, which was confirmed by FTIR.Chemical sorption dominated the binding of dye molecules.Different functional groups were ionized in different pH conditions and played a pronounced role in the sorption.
    Effect of combustion process on pore structure of oil shale ash
    HAN Xiangxin;JIANG Xiumin;WANG Dezhong;CUI Zhigang;YU Lijun
    2007, 58(5):  1296-1300. 
    Abstract ( 903 )   PDF (415KB) ( 248 )  
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    Oil shale ash, an inorganic byproduct of burning oil shale and retored shale, has a potential use, such as building material,chemical filling material,adsorbent, etc. To obtain oil shale ash with higher porosity, the pore structure of oil shale ash produced by the combustion of oil shale was measured by using the N2 isothermal adsorption/desorption method.As a result of comparison between oil shale ash samples prepared under different combustion conditions in terms of pore structure, the oil shale ash, formed under both higher heating rate and particle final temperature lower than the melting point of oil shale ash, had a larger pore volume and specific surface area and could be utilized in industries.
    Preparation and electric properties of La0.6Sr0.4-xCaxCo1-yNiyO3-δ composite doped perovskite oxide cathode
    LI Yan;LUO Zhongyang;YU Chunjiang;WEI Xinli;CEN Kefa
    2007, 58(5):  1301-1306. 
    Abstract ( 847 )   PDF (542KB) ( 273 )  
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    Composite doped ITSOFC(Intermediate Temperature Solid Oxide Fuel Cell ) cathode material of La0.6Sr0.4-xCaxCo1-yNiyO3-δ(LSCCN)was synthesized through solid-phase reaction.The crystal structure and forming process of LSCCN powder were investigated with XRD.The experimental results showed that Ca2+ could not be well mixed into the LaCoO3 lattice when x was 0.4.The crystal structure of the material was stable when the metal molar percentage of Ni was less than 5%, but it lost the single perovskite phase structure and presented the square K2NiF4 phase of LaSrCoO4 when the content of Ni increased.The SOFC(Solid Oxide Fuel Cell) cathode wafers could be made by mixing a specific amount of amylum and ethylic cellulose with LSCCN cathode powder.The electrical conductivity of the samples was measured by using the four-probe DC method from 100℃ to 800℃ in atmosphere.The electrical conductivity of the cathode wafers with perovskite structure was higher than 105 S·m-1, in which the electrical conductivity of the La0.6Sr0.2Ca0.2Co0.9Ni0.1O3-δ samples could reach 57701 S·m-1 when heated up to 800℃.The sample single crystal lattice structure changed significantly and its electrical conductivity decreased considerably when the molar percentage of Ca2+ or Ni2+ increased.
    材料化学工程与纳米技术
    Mechanical activation effects on crystal structure and chemical reaction activity of maize starch
    HUANG Zuqiang;CHEN Yuan;QIAN Weijin;TONG Zhangfa;QIN Xuejiang;LI Xuanhai
    2007, 58(5):  1307-1313. 
    Abstract ( 714 )   PDF (859KB) ( 412 )  
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    Maize starch was mechanically activated by a stirring-type ball mill.The effects of mechanical activation on crystal structure,thermal properties,granule shape and particle size of maize starch were examined by means of X-ray diffraction,differential scanning calorimetry,scanning electron microscope and particle size analyzer.Moreover,mechanically activated maize starch(MAMS)with different activation times was acetylated with acetic anhydride and graft-copolymerized with acrylamide under the same experimental conditions.The mechanical activation effects on chemical reaction activity of maize starch were investigated by analyzing the influence of mechanical activation on degree of substitution(DS)of esterification and grafting rate(G)and grafting efficiency(GE)of graft copolymerization.The results indicated that the DS,G and GE of MAMS were higher than that of native starch,and showed obviously enhanced chemical reaction activity of maize starch by mechanical activation.The crystal structure and compact granule surface of maize starch were destroyed by mechanical activation,and the crystallinity decreased from polycrystalline to amorphous.With increasing activation time,the gelatinization temperature and pastes viscosity of MAMS decreased and its fluidity was enhanced.As a consequence,the resistance of reagents diffusing into starch solution would be reduced and it was easier to diffuse into starch intramolecule.
    Free radical seeded emulsion polymerization with participation of hydrolysis-condensation reaction(Ⅱ)Parameters and modeling application
    NI Kefan;SHAN Guorong;WENG Zhixue
    2007, 58(5):  1314-1319. 
    Abstract ( 784 )   PDF (973KB) ( 264 )  
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    The emulsion polymerization with the simultaneous hydrolysis-condensation reaction is an important method to synthesize the organic-inorganic hybrid nanoparticles.Its process modeling and simulation is really a challenge due to the complicated reaction mechanism.In the previous paper of the authors,a model was developed based on the analysis of the process mechanism.In this paper, the kinetic model of this process was calculated to simulate this complicated process.The model was used in the seeded emulsion copolymerization system of 3-trimethoxysilyl propyl methacrylate (MPS) and styrene.The kinetics simulated by the presented model was compared with the experimental data obtained by gas chromatography (GC) and solid-state 29Si NMR along with the emulsion copolymerization process.As predicted by the model and proved by experiments, the hydrolysis could be divided into two phases characterized by the different rates.At the beginning of the reaction,hydrolysis was more active because of the part of silicone groups existing in the water phase. A greater MPS addition amount would increase the MPS concentration in the water phase and then strengthen the hydrolysis and condensation reactions.A greater surface area of latex particles would increase the hydrolysis rate because more SiOR groups could contact with water in this case.The parameter f was directly related to the surface area and decreased with more MPS content in the shell polymer.A semi-empirical equation of the parameter f was derived.
    Structural rheology of immiscible PET/PP blend
    WU Defeng;CAO Jian;WU Lanfeng;ZHANG Ming
    2007, 58(5):  1320-1324. 
    Abstract ( 756 )   PDF (1150KB) ( 371 )  
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    The immiscible poly(ethylene terephthalate)(PET)/polypropylene(PP)blend was prepared by melt mixing and its structural rheology was studied.The results showed that the immiscible morphology influenced both the dynamic and steady-state rheological behavior of PET/PP blend.The blend with dispersed PP domain/PET matrix morphology showed a dynamic shape relaxation,while that with dispersed PET domain/PP matrix morphology only showed a small sensitivity to shear action.For the blend with complicated phase structure,the low-frequency elastic response could be observed clearly.Moreover,the agglomeration of the dispersed drops was the dominant factor affecting the rheological behavior under a higher shear field,while the break-up of drops became the dominant one under a lower shear field.
    Adsorption of Au(Ⅲ)on chloromethylthiirane crosslinked chitosan resin in chlorating system
    DANG Mingyan;ZHANG Tingan;WANG Ping;LI Wei
    2007, 58(5):  1325-1330. 
    Abstract ( 629 )   PDF (1145KB) ( 420 )  
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    Chloromethylthiirane was used as crosslinking agent to synthesize chloromethylthiirane crosslinked chitosan (CCCS) resin,which was characterized with SEM and FTIR.The adsorption kinetics and adsorption equilibrium of Au(Ⅲ)on CCCS resin were also studied.The results showed that chloromethylthiirane had a ring-opening reaction during the crosslinking process in which sulfhydryl was formed, —NH2 and —HS of CCCS had a share in coordination with Au(Ⅲ)in the adsorption, the adsorption rate followed the second-order kinetics model of Legergren,and the apparent energy of activation was 16.039 kJ·mol-1. The isothermal adsorption followed the isothermal adsorption equations of Freundlich and Langmuir.The adsorption process was a exothermic physical adsorption.
    Synthesis and conductivity of ferrocenyl Schiff base and its salt
    LIU Weijun;XIONG Guoxuan;HUANG Haiqing
    2007, 58(5):  1331-1336. 
    Abstract ( 710 )   PDF (1214KB) ( 649 )  
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    Ferrocenyl Schiff base was synthesized with ferrocenecarboxaldehyde and p-phenylenediamine as precursors under neutral condition. The effects of the temperature and time of reaction on the yield were investigated, and the room-temperature electric conductivity of the intrinsic sample was 1.26×10-9 S·cm-1.The doping of ferrocenyl Schiff base with Fe3+, Al3+ and Ti3+ salt,and the effects of the dosage of doping agent and doping temperature on the room-temperature electric conductivity of samples were discussed. In addition, the temperature dependence of electric conductivity of samples were studied, and their structures and compositions were characterized with infrared spectrum, ultraviolet spectrum and electron probe X-ray microanalyser.The results showed that the electric conductivity of the sample could increase 4~5 by orders of magnitude after doping with metallic salt. The electrical activation energies of the complexes in the range of 0.09~1.54 eV were calculated from Arrhenius plots, indicating their favourable semiconducting behavior.