Hydrate formation conditions of (CH₄+CO₂+H₂S) ternary sour natural gas mixtures in the presence of pure water were measured by using transparent sapphire cell device.The experimental temperature range was 274.2 to 299.7 K and pressure range was 0.58 to 8.68 MPa.The hydrogen sulfide and carbon dioxide contents in the gas mixtures varied from 4.95%(mol) to 26.62%(mol) and 6.81%(mol) to 10.77 %(mol), respectively.The hydrate phase equilibria data for sour natural gas in water were also predicted based on the Chen-Guo hydrate model and CSMHYD model.The calculation deviation increased, in general, with increasing H₂S concentration in the gas mixture and the Chen-Guo hydrate model gave better predictions.However, both models are subjected to further improvement for high H₂S content ［e.g. >10%(mol)］ systems.

The adsorption of catechin by using self-made ion exchange fiber(IEF) adsorbent was studied. Equilibrium data for the adsorption of catechin from aqueous solutions by IEF adsorbent within the temperature range of 286—328 K and observed concentration range were obtained and correlated with the Langmuir-type and Freundlich-type isotherm equations. Freundlich adsorption isotherms and isosteric enthalpy of the adsorption of catechin indicated that the process of adsorption of catechin from aqueous solutions by IEF was an endothermic process. Estimations of the isosteric enthalpy of adsorption, free energy, and entropy of adsorption were reported, and the adsorption behavior was reasonably interpreted.

To determine and calculate oxygen solubility in acetic acid-water mixed solvents, a set of apparatus for measuring gas solubility in liquid and a new model of calculating gas solubility in associated mixed solvents are reported in this paper.The apparatus could continuously be used to measure several solubility data under various pressures when solvents were fed once. The solubility of oxygen in acetic acid-water mixed solvents at 25—80 ℃ were determined with this apparatus.A new model of calculating oxygen solubility in associated mixed solvents of acetic acid and water was established. The parameters of the above model were correlated from the experimental solubility data by simplex optimization. The average relative error of calculation was no more than ±3.0%, so this new model could be used to calculate oxygen solubility in acetic acid-water mixed solvents.

Modeling and simulation based on computational fluid dynamics and heat transfer for the metal structured packed bed were carried out to predict the flow field and temperature field, and to evaluate its performance in heat transfer and hydrodynamics.The effects of geometric parameters and the properties of solid phase on heat transfer of the structured packed bed were discussed.It was found that at low Re and the same properties and voidage of the packed bed, the larger the specific surface area, the better the ability of heat transfer of the packed bed.Furthermore, the comparison between the simulation results of the metal structured packed bed and heat transfer performance and pressure drop of the pellet packed bed was made, which validated better transport performance of the metal structured packed bed.

The wedge-shaped space of the gradient magnetic field composed of neodymium-iron-boron was set up and experimental research on the natural convection heat transfer of oxygen gas in enclosure was presented based on magnetothermal convection induced by the gradient magnetic field.The laser speckle interferometry image for the natural convection of oxygen gas was obtained and the local Nusselt numbers as well as the temperature field could thus be derived.The results showed that the natural convection of oxygen gas was enhanced by using the gradient magnetic field in which magnetic acceleration is almost identical with gravitational acceleration in direction.

Most of residual volatiles in polymers, which normally result from synthesis processes of the polymers, have negative impacts on the end-use properties of the polymer materials. These volatiles should be minimized or at least be reduced to a level below the permissible limit. Conventional techniques for polymer devolatilization have shown limited effectiveness when the volatile concentration is at a low level. With the assistance of supercritical fluids, however, the operation for the removal of the volatiles from polymers can be enhanced. The quantities of the volatile, ethylene glycol (EG), in polyethylene terephthalate (PET) films at different times were determined in the presence of supercritical carbon dioxide (SC-CO₂) at a temperature of 343 K, pressure of 30 MPa and CO₂ flow rate of 4.0 L•min^-1, based on which the SC-CO₂-assisted removal of EG from PET film matrix was investigated. A mass transport model was derived by means of the mass transport theory.Comparison of the model predictions with experimental results showed that the model reflected the essential features of supercritical fluid devolatilization of polymers.

Fuel thermal bake-out is a new method to heat and start up the aluminum reduction cell.And the fume thermal technology,i.e. using high-temperature fume to heat and start up the aluminum reduction cell, is an ideal method to heat the aluminum reduction cell, which can overcome the shortage of fuel thermal bake-out.The study on the rational burner structure is the key to obtaining perfect thermal result.A study on combustion in the burner for fume thermal bake-out was made by numerical simulation.Combustion performance and influencing factors of the burner were predicted.The study showed that installing a precombustion chamber could help improve complete combustion of the burner.The terfiary air near the chamber wall could lower the temperature of the chamber inner wall.The study results provided the theoretical basis for optimum design of burner structure.

A discrete particle motion-collision decoupled model based on dense gas molecular dynamics and gas-solid two-phase fluid dynamics of dense gas-solid flow in the fluidized bed was developed. Particle collision was modeled by means of the direct simulation Monte Carlo (DSMC) method.The large eddy simulation(LES) accounting for the effect of particle fluctuation was used to model gas turbulent flow. The Newtonian equations of motion were solved for each individual particle in the system. The interaction between gas phase and particle phase was determined by means of Newtonian third law. The flow behavior of gas and particle phases were numerically simulated in a circulating fluidized bed. The distributions of gas and particle velocity and particle concentration in the riser were analyzed.The number-averaged duration time, the ratio of total cluster duration time to total observation time and the cluster frequency were obtained in the circulating fluidized bed. The simulated results were in agreement with experimental measurements of literatures in the circulating fluidized beds.

A comparison of three PIV algorithms: FFT-based cross-correlation (FFT-CC) method, direct cross-correlation (DCC) method, and minimum quadratic difference (MQD) method was performed by applying these methods to low number density PIV images obtained by the Japan Visualization Society.Raw results of the MQD method were better than those of the FFT-CC, but validated results of the FFT-CC method were better than those of the MQD method. Results of the DCC method were the worst.There was discrepancy between results of the same algorithm with different sizes of the interrogation window.It mainly resulted from various amounts of matched particles of sub images.This study could provide good reference to the selection of the algorithm and its parameters.

The transportation characteristics of aerosol particles in capillaries were studied with Monte Carlo simulation based on the diffusion model of aerosol particles,and the relationship between penetration and flow velocity was also investigated.It was shown that the penetration of aerosol particles significantly depended on the mean flow velocity.The penetration of aerosol particles remarkably increased with increasing mean flow velocity.It was also found that the mean retention time,half-peak width and penetration derived from the simulation were virtually consistent with experimental results.

The investigation of hydrodynamic behavior in three-phase external loop airlift reactors is important to their design and scale-up. Pressure difference was used to measure gas holdup and ultrasonic Doppler anemometry was used to measure liquid velocity. Gas holdup, liquid velocity and expansion rate increased with increasing superficial gas velocity. Under the same superficial gas velocity, gas holdup increased with increasing static solid height, and decreased with increasing solid particle diameter.Adding large particles could increase interfacial area, increase gas residual time and intensify mass transfer. Liquid circulation velocity and expansion rate decreased with increasing solid particle diameter and static solid height.Liquid velocity could be controlled in a suitable range by adding particles to improve the performance in airlift loop reactors.

Based on the laminar diffusion model, the micro-mixing in a rotating packed bed (RPB) was discussed by taking the competitive and consecutive azobenzene reaction between 1-naphthol and diazotised sulphanilic acid as reaction system. A mathematical model was presented to describe the whole process of the reaction by introducing two parameters that could impose adjustment between the reactants and the resultants. The reaction was calculated and the results were consistent with the experimental data.

The ruthenium catalyst supported on activated carbon was prepared by the impregnation method. The effect of such factors as dryness, pH value during precipitation, surface area and porosity of the activated carbons, sequence of precipitation, etc on the catalytic activity and Ru dispersion were studied during preparation. The results showed that activated carbon should be dried at 100—200 ℃ for 6—8 h before precipitation. Also, activated carbon must have enough surface area, especially the developed mesopores, which provided enough sites for Ru deposition. It was also found that the surface area and porosity of activated carbon changed greatly during precipitation. Barium promoters might provide the deposition surface for Ru, while potassium might fill in mesopore and contact with Ru, providing electrons for Ru. In order to obtain good Ru dispersion, the pH of the aqueous solution of RuCl₃•3H₂O should be controlled at 0.40—1.05, and the sequence of precipitation should be Ba-Ru-K. Only then could good performance of Ru-based ammonia synthesis catalysts be achieved.

Conversion of phthalic anhydride (PA) could be improved significantly at mole ratio of 1∶1 (PA∶nitrobenzene) by adding nitrobenzene into the usual Friedel-Crafts(F-C)reaction solution DCM.Nitrobenzene’s effect was found to be different from the usual DCM in F-C reaction, because nitrobenzene might participate in the intermediate reaction.In addition,the method of adding nitrobenzene and mole ratio of PA to nitrobenzene could affect the experiment results.Carboxylic crosslinked polystyrene microsphere was prepared by F-C acylation reaction.

A new kind of oligomer was synthesized by using resorcinol and acetone as reactants in the presence of acidic catalyst.The molecular mass of resultant oligomers investigated by GPC ranged from 840 to 1320 with the variation of the molar ratio of acetone to resorcinol in the reaction system.Firstly, based on the analysis of ¹H NMR and ¹³C NMR spectra, the hydrogen atom located on the site 2 in the benzene ring of resorcinol could not react in the synthesis of oligomer because of steric hindrance which made the reactivity of hydrogen atom in the position of 2 considerably lower than that of hydrogen atoms in the position of 4 or 6 in the resorcinol.Therefore, the functionality of resorcinol here was confined to be 2.On the other hand, the analytical result of the gravimetric method showed that the molar ratio of acetone to resorcinol in the oligomer was always smaller than 2 even if the amount of acetone was in excess of 5 times of resorcinol in the reaction system.Additionally, the oligomer had favorable solubility in ordinary organic solvents such as ethanol, acetone, THF and so on.Consequently, the resultant oligomer was linear, rather than network.Secondly, the unit structures of the oligomer were proposed according to the analysis of the FT-IR spectrum.Finally,a reasonable mechanism of the reaction of acetone with resorcinol catalyzed by acid was put forward which could explain the process of the reaction of acetone with resorcinol well.

Aquathermolysis reaction of heavy oil in the presence of metallic salt and formation mineral was studied.A five-lumped kinetics model,comprising of gas, saturate, aromatic, resin and asphaltene, was established on the basis of experimental results.The reaction rate constant and the activation energy were calculated by using the Runge-Kutta integral and complex method. The results indicated that resin was the center of reactions and main source of light component increase such as gas, aromatic and saturate.Asphaltene changed into resin mainly.The model prediction was consistent with the experimental data,which suggested that the five-lumped kinetics model is reasonable.

Molecularly imprinted polymers(MIPs) for theophylline were synthesized using methacrylic acid as monomer, ethylene glycol dimethylacrylate as crosslinker, chloroform, tetrahydrofuran and dimethyl sulfoxide as individual solvent, respectively. The adsorption performance of the imprinted polymers was determined in terms of capacity and selectivity, and the polymer synthesized by using chloroform as solvent resulted in the highest capacity and selectivity.The adsorption mechanism was investigated by using Scatchard analysis. ¹H NMR was used to assess the formation of H-bond between imprinted molecule and monomer in order to provide an insight into the molecular interaction between solvent with template molecule and monomer, respectively. The solvation energy, an intensity index of the molecular interactions between solvent with imprinted molecule and solvent with monomer was calculated with the Density Functional Theory (DFT) method. The MIPs synthesized in the solvent that provided lower solvation energy resulted in better molecular recognition ability, which was in good agreement with experimental observation and ¹H NMR analysis.The results show the importance of solvent choice in molecular imprinting and demonstrate that computational quantum chemistry analysis can assist in choosing a solvent for the synthesis of MIPs.

The characteristics of the time-averaged frictional pressure drop in single-phase flow, which was determined by the air purge method, for the HNO₃ solution and 30% TRPO-Kerosene solution through a 50mm-diameter discs and doughnuts pulsed extraction column were studied firstly.Experimental results showed that the time-averaged frictional pressure drop could be neglected at the condition of A′ω≠0 and u_c=0, but Noh’s linear relation to uc at A′ω=0 was satisfied.The frictional pressure drop could be estimated by Noh’s model at A′ω≠0, which was improved for the discs and doughnuts pulsed extraction column.The values predicted by the model were in good agreement with those obtained by experiments.Then the time averaged frictional pressure drop in two-phase flow and the dispersed phase holdup in the column, for the HNO₃ solution and 30% TRPO-Kerosene solution were studied.Experimental results showed that Noh’s model, which was developed for the reciprocating plate extraction column could be used for estimating the dispersed phase hold-up in a discs and doughnuts pulsed extraction column. Here, it was stressed that in the model, the two-phase time averaged frictional pressure drop, Δp_f, could be predicted by the equation for the single-phase flow that is the corresponding continuous phase in the two-phase flow.

Separation of acetic acid-water-butyl acetate system is a gas-liquid-liquid three phase azeotropic distillation process, and phase splitting judgment and algorithm improvement are the main issues in distillation simulation. According to published experimental data,rigorous thermodynamic models were presented to predict the activity and fugacity coefficients, and based on Gibbs free energy curves thermodynamic stability was analyzed to obtain a phase splitting criterion and phase splitting region for the acetic acid-water-butyl acetate system. Further, a new algorithm suitable for highly nonideal and multiphase distillation was developed to simulate acetic acid-water-butyl acetate distillation process. The simulation results were verified by comparison with industrial data, and the method was proved to be accurate enough to simulate the existing industrial process.

Experimental results indicated that the resin of 4-aminopyridine (4-APR) showed good ability to adsorb Mo(Ⅵ) at pH=4.1 in the HAc-NaAc medium.The statically saturated sorption capacity was 594 mg Mo(Ⅵ)•(g resin)^-1，Mo(Ⅵ) adsorbed on 4-APR could be eluted by 3 mol•L^-1 HCl or 3 mol•L^-1 NaOH quantitatively. The sorption rate constants determined at various temperatures were respectively k15℃=2.24×10^-5s^-1,k_25℃=3.30×10^-5s^-1,k_35℃=4.79×10^-5s^-1,and k_45℃=6.85×10^-5s^-1.The sorption apparent activation energy Ea was 29.1 kJ•mol^-1.The sorption mechanism showed that the nitrogen atoms of the functional group of 4-APR coordinated with Mo(Ⅵ) to form coordination bonds,and the coordination molar ratio of ［4-AP］ to Mo(Ⅵ) was 1∶2.

Radial basis function-cyclic subspace regression (RBF-CSR) approach is a rapid one-step modeling method, escaping the difficulty of ANN architecture design. ANN and multivariate analysis are integrated into this approach, but it is difficult to optimize the parameters of the model because the method is a mixed integer programming.A eugenic hybrid coding genetic algorithm（EHCGA）, which used different coding methods for different type of variables was proposed to give the optimal parameters of the RBF-CSR model. In EHCGA deterministic optimization method was added to standard GA based on eugenic strategy, which could greatly improve the convergence speed and accuracy of GA. RBF-CSR model optimized by EHCGA called RBF-CSR-EHCGA model was successfully applied to modeling recovery of caprolactam from waste water by using pulsed-sieve-plate extraction column.

For solving dynamic optimization problems with fixed boundary, a novel strategy named as graded optimization was developed. It had two alternative schemes, of which the one was to deal with the constraint of fixed boundary prior to objective optimization, while the other one was to treat them in the reversed procedure. By using this strategy a fixed boundary problem was reduced to a series of free boundary problems that could be solved by using existing,sophisticated optimization methods. For boxing constraint of control, trigonometric function transformation was developed to achieve an unconstrained problem. Graded optimization had the abilities to avoid the demerits of penalty function strategy. Case studies showed that graded optimization could meet fixed boundary requirements with reasonable accuracy and trigonometric function transformation was feasible.

Cephalosporin C fed-batch cultivation undergoes great fluctuations. Some key state variables, such as product concentration and carbon source consumption, are very difficult to measure on-line, while these variables are essential to process monitoring and control.A neural network based software prediction of the key state variables for cephalosporin C fed-batch fermentation was investigated. A rolling learning-prediction procedure was used to deal with the time variant property of the process, and was also demonstrated to be beneficial to improving prediction accuracy.The successful prediction of the product formation enabled on-line evaluation of the economic performance of a charge and made optimal scheduling possible.The prediction approach was validated with the data of 49 industrial charges.

In the present work, oil-in-water emulsions were prepared with toluene-water as working system, sodium lauryl sulfate as emulsifier,and α-Al₂O₃ ceramic membrane with pore size of 1.5 μm as emulsifying medium in a new submerged emulsification apparatus. The effects of stirring speed,transmembrane pressure and emulsifier concentration on the droplet size of emulsions and its distribution as well as the dispersed phase flux were studied. The experimental results showed that monodispersed oil-in-water emulsions could be obtained with the ceramic membrane emulsification system. With the increase of stirring speed and emulsifier concentration, mean droplet size and the span of the droplet size distribution decreased, and the dispersed phase flux hardly changed at the same time.However,mean droplet size and the span of the droplet size distribution increased, and the dispersed phase flux increased significantly with the increase of transmembrane pressure. A linear relationship between the dispersed phase flux and transmembrane pressure at low pressures was obtained.

The feasibility of surfactant assisted refolding, which was performed by diluting denatured protein sample into a refolding buffer containing a surfactant of appropriate concentration, was examined by using recombinant human lysozyme (rhLys) and recombinant β-mannanase (rMan) as protein samples.The effectiveness of CTAB, an artificial chaperone consisting of CTAB and β-CD, as well as other kinds of surfactants was investigated respectively.The effects of these surfactants on refolding yield and product distribution were determined by using biological activity assay, non-reductive SDS-PAGE and fluorescence emission spectrometry. A significant increase in refolding yield occurred for rhLys when using CTAB and the artificial chaperone, compared to that obtained by using direct dilution. Moreover, the refolding of rhLys presented similar process characteristics to that of native lysozyme (Lys).In both cases, the yield and product distribution depended on the molar ratio of surfactant to protein. The artificial chaperone worked also for rMan, particularly at a high concentration of the denatured rMan. It was shown that the charge property and concentration of surfactant, and the concentration of protein being refolded are major parameters determining the success of refolding process. The results described above are helpful to both the understanding of process mechanism and the application of this new refolding method.

A newly isolated strain was identified as Microbacterium sp. ZD-M2, which can specifically remove sulfur from the model compound of dibenzothiophene (DBT). Metabolites were identified by gas chromatography-mass spectrometry, and the results showed that 2-hydroxybiphenyl, the end product of the previously reported sulfur-specific pathway (also called 4S pathway), was further converted to 2-methoxybiphenyl. Biphenyl was also produced as the deoxidized metabolites. In aqueous phase the strain grew well in the pH range of 6.5—9.5.The optimal temperature for growth was 30 ℃ and the appropriate concentration of ammonium chloride as the source of nitrogen was 1.0 g•L^-1. Glycerol and DBT were selected as the best carbon and sulfur sources for its growth, and the optimal concentrations were 2.0 g•L^-1 and 0.2 mmol•L^-1,respectively.

A mathematical model combining heat transfer with mass transfer of MAWE of icariin from Epimidium sagittatum leaves was developed.On one hand the model considered the effect of temperature gradient on effective diffusion coefficient D_e. On the other hand, the model took internal porosity ε as a function of extraction time t, which resulted in D_e changing with the change of the average temperature of system and the extraction time t.The implicit difference method was used to solve the 1-D parabolic PDE(partial differential equation).Distribution plots of temperature of material and concentration of icariin changing with the thickness of material and the time of extraction was drawn.The result showed that the temperature gradient was from the internal of material to solvent after microwave irradiation, the direction of temperature gradient and that of mass transfer was concurrent.The effectiveness of the mathematical model was verified by the concentration of icariin in solvent.The solutions of mass transfer model agreed with the experimental data.The biggest relative deviation of icariin concentration in liquid was less than 10%.In order to verify the model proposed in this paper, the traditional extraction process was also simulated, and the result showed good agreement between solutions of the model and the experimental data.

A steady-state, three-dimensional, non-isothermal gas-liquid two-phase mathematical model of the proton exchange membrane fuel cell (PEMFC) was developed to study transport phenomena in the whole fuel cell. This comprehensive model accounted for almost all important transport phenomena in the fuel cell such as fluid flows, heat transfer, mass transfer, electrochemical kinetics and charge transfer, as well as the effect of phase change on mass transfer and temperature field. A special feature of this model was that it allowed detailed modeling and prediction of electrochemical kinetics. The transport of electrons in the backing layer and catalyst layer was accounted for, as well as the transport of protons in the membrane and catalyst layer. Spatial distributions of temperature, species concentrations and current were illustrated and discussed in detail.Lastly,a comparison of predicted performance and experimental data in literature was made to validate the mathematical model.

Dynamic characteristics are very important for transportable power sources with direct methanol fuel cells. The dynamic voltage responses to variable current of a single direct methanol fuel cell were studied.With the aid of computer-controlled electronic load, cell potential dynamic responses to current loading cycle,magnitude of loading current, constant loading/rest time and slope of increasing current were investigated. Experimental results indicated that the fuel cell responded rapidly to dynamic change of current cycle. Open circuit voltage of the fuel cell under dynamic operating condition was higher than that under steady state operating condition.The slope of increasing current significantly affected the cell dynamic response.The interaction between electrochemical reactions and transient heat/mass transfer inside the fuel cell made key contribution to dynamic response of the fuel cell.

Hydrogen production from hydrogen sulfide, a byproduct in oil refinery has been a widely studied problem in recent years and the kinetic studies in this field is also important for the process to be used commercially.A macroscopic kinetic equation was derived,after considering all factors affecting electrode reaction and investigating the process of mass transfer in actual conditions pilot-scale. The kinetic equation was tested in pilot plant and found in agreement with experimental data.The concentration of hydrogen ion, voltage on electrobath and the temperature of electrolyte were the main factors affecting hydrogen production from indirect electrolysis of hydrogen sulfide and the voltage on electrolytic cell took a most important part in the process. The equation given could be used as theoretic basis for later studies in increasing the rate of hydrogen production.

The reaction between CaS and CaSO₄ with different molar ratios in N₂ atmosphere was investigated with a Metteler Toledo thermogravimetric analyzer.In this work, the chemical reaction kinetics and mechanism were discussed in detail.The reaction between CaS and CaSO4 was the rate-controlling step in the oxidation of CaS to CaO.When CaSO₄ was in excess,the reaction proceeds in two steps.The apparent solid-solid reaction between CaS and CaSO₄ started at 890 ℃ and ended at 1120 ℃.Then the residual CaSO₄ continued decomposing in the range of 1160—1330 ℃.When the molar ratio of CaSO₄ to CaS was 3, the maximal activation energy of 302.46 kJ•mol^-1 was obtained.The reaction mechanism could be explained by a eutectic liquid model.

The electroreduction process of nitrobenzene, which consists of a series of elementary processes, is a complicated reaction system. Besides p-aminophenol, some by-products, such as azoxybenzene, azobenzene and diaminodiphenyl ether can also be produced in the process. These by-products which hardly dissolve in H₂SO₄ aqueous solution will adsorb and deposit on the surface of membrane material gradually and thus pollute the membrane material, which causes increases in bath voltages and decreases in current efficiency. In the paper, from the viewpoint of engineering application the fouling and cleaning processes of Nafion membrane in the direct electrochemical synthesis of p-aminophenol were investigated.In the process of direct electroreduction of nitrobenzene, the bath voltages and the current efficiency at different service times of Nafion membrane were measured, respectively.The fouling ratio of membrane and the cleaning degree of fouled membrane, characterized with bath voltage, were defined in this paper. Further, the fouling rate equation of Nafion membrane was presented.With the equation, the fouling rates and the fouling ratios of Nafion membrane at different service times could be calculated easily. Meanwhile, the bath voltages and the current efficiency at the different service times of Nafion membrane could be calculated easily as well. A kind of membrane cleaning agent consisting of anionic surfactants(AES,ABS and R-3), nonionic surfactants(JFC,APG-10 and Tween-60), isopropanol and water, was presented.When the fouled Nafion membrane was cleaned by the cleaning agent online for 2 h in the condition of pH≈13, 60 ℃ and 4 L•min^-1 circulation velocity, the bath voltage,SEM morphologies of membrane and membrane resistances could be restored to those of the initial membrane basically.The cleaning degree of fouled membranes was still close to 1 after the cleaning agent was used for 5 times repeatedly, and the strength of rinsed membranes was still the same as that of the initial membrane.

The energy changes and microscopic parameters resulting from the interaction of hydrogen and two kinds of defects on carbon nanotubes chair(5,5), chair(6,6) and zigzag(10,0) were calculated by using molecular dynamics and quantum chemistry. The average energy per atom of carbon nanotubes reflected the tension and torsion of the conjugated surface. According to the cohesive energy obtained by calculation,the interaction was found to be relevant to the type and position of the defects.Hydrogen molecule passed most easily from the defect formed by removing one carbon atom and located in the middle of carbon nanotubes. According to bond energy, bond order and net charge, it was concluded that the carbon atoms on the edge of defects were positively or negatively charged by turns, the symmetry of the defects were reduced due to the interaction of hydrogen.More negative charges were enriched on the edge,and the distribution of net charge became more inequal. The interaction of hydrogen and the defect mainly occurred on the three carbon atoms most close to the hydrogen molecule, and influenced the microscopic properties.

The coupled effect of photocatalytic activity of CdS/TiO₂ composite semiconductor was studied.CdS/TiO₂ nano-powders with different ratios of CdS∶TiO₂ from 0.005 to 2.0 were synthesized by the hydrothermal method at 200 ℃ for 6 h using titania, cadmium chloride and sodium sulfide as reactants. The CdS/TiO₂ powders were characterized by XRD, SEM, EDS, IR and the diameter of the particles was evaluated by Scherrer equation. XRD patterns showed that the crystallinestate of CdS/TiO₂ samples was a mixture of anatase, zinc-blend and wurtzite. SEM micrographs showed that the diameter of CdS particles was 20—50 nm and the diameter of TiO₂ particles was 50—100 nm. The photocatalytic activities of CdS/TiO2 nanopowders were measured by photo-degradation of rhodamine B. When the mole ratio of CdS∶TiO₂ was 1.0, the coupled effect of photocatalytic activities appeared.When the mole ratio of CdS∶TiO2 was 1.5, the coupled effect became the strongest, and the degradation rate of rhodamine B(4 mg•L-1) irradiated by ultraviolet ray for 30 minutes was 74.3%.

The interface problem between carbon fiber and copper is very serious because of the poor wettability between carbon fiber and copper.Therefore the excellent performance of C_f/Cu composite is badly affected.The interface problem of C_f/Cu composite could be resolved when the carbon fiber is coated with copper through electroless plating and then mixed with copper.However it is very difficult to deposit copper onto carbon fiber because carbon fiber was tenuous and hydrophobic. The effect of four kinds of additives A（alkyl benzene sulfuric salt）,B（alkyl sulfuric salt）,C（dodecyl fatty salt）and D（dodecyl fatty salt + sodium acetate） was discussed respectively when bluestone was used as main salt and zinc as reducing agent to deposit copper onto carbon fiber. The result showed that additive D was the best one in copper plating and the problem of black-core that often occurred in the course of copperizing a bundle of carbon fiber was effectively resolved.SEM showed that every carbon fiber was coated with even and continuous copper in the experiment,the interface bonding between carbon fiber and copper was firm, and carbon fibers combined with copper tightly in the composite.

The purpose of this work was to investigate the effect of hydrothermal modification conditions on the preparation of flame retardant Mg(OH)₂ synthesized via MgCl₂-NaOH route in a large-scale experimental set-up designed by the authors.Hydrothermal modification temperature, hydrothermal modification time, concentration of aqueous CaCl₂ solution and solids holdup of Mg(OH)₂ particles showed important effect on the morphology, crystalline structure and dispersion properties of the hydrothermal products. Based on optimal hydrothermal modification conditions, the regular hexagonal plates of Mg(OH)₂ with uniform size and smaller BET surface area were formed after the hydrothermal treatment.

MMT emulsion after sonication was blended with polymer latex.Polymer/MMT nano-composite coating was formed by simply evaporating water, just like the case of conventional emulsion coating.Polymer/MMT nano-structured film could be formed by this colloidal packing method. Tensile strength and modulus of the films dramatically increased with increasing of MMT content up to 10%（mass）. Polar functional groups introduced on the surface of the polymer particles were found to enhance tensile strength. These polar functional groups also played a key role in controlling the morphology of nano-structured films, leading to the dependence of modulus of the films on the types of functional groups.

High-purity nanosized magnesium hydroxide was prepared by the direct alkali hydrolysis method using hexammoniated magnesium chloride as raw material.The optimum reaction condition was obtained through experiment: the mixture of 10% sodium hydroxide and highly concentrated hexammoniated magnesium chloride reacted under a homogeneous machine for 5 h at room temperature,was deposited, filtered and washed, and then dried.The analysis of chemical composition and transmission electron microscopy (TEM) showed that the particle size was smaller than 100 nm, the content of magnesium hydroxide was about 99.7%, and the content of impurity was lower than 0.3%.

Electrochemical polarization measurement and electrochemical impedance spectroscopy(EIS) were used to study the corrosion inhibition effect of 1-dodecanethiol on copper in 3% NaCl solution.The results showed 1-dodecanethiol had better corrosion inhibition effect on copper.The corrosion inhibition ability of 1-dodecanethiol was decreased with the adding of benzotrizole, while the same degree of corrosion happened without benzotrizole when pH value of the media decreased to about 1.0.The above corrosion inhibition behavior was supported by SEM.

A series of casting polyurethane (CPU)resins were synthesized by using 4,4′-methylene diphenyl dissocyanate (MDI), polyols, crosslinking agent,special aids, and a number of heat resistant polyurethane resin were prepared by semi-prepolymerization.Their structures were studied with FTIR，the thermal stability of CPU was examined with DSC and TGA.The mechanical property of CPU were measured.The CPU with high thermal stabilities and excellent mechanical properties could be used in the fields of high temperature, high impact strength, etc.

A process based on the suspended particle technique was used to deposit Al₂O₃ micro-filtration membranes on α-Al₂O₃ support,α-Al₂O₃ supports with four different pore sizes were analyzed.The effects of surface roughness, pore size of support and matching condition between support pore size and suspension particle size on the integrity of micro-filtration membranes were discussed.The results showed that an integral crack-free membrane could be made with smooth support surface and fine matching between suspension particle size and support pore size.The test data showed that the limiting ratio between support pore size and suspension particle size was 10.When the ratio was more than 10,the membrane thus made would have surface cracks, wide distribution of pore size and small porosity.When the ratio was less than 10,the membrane thus made would have crack free surface, narrow of distribution of pore size and large porosity.