The turbulence properties of separation space in a cyclone were investigated by using the Laser Doppler Velocimetry. In some areas, such as inner vortex flow, vicinity of the wall,intersection between upward flow and downward flow,intersection of inner vortex flow and outer vortex flow, the distribution of turbulent intensity varied sharply, and turbulence was quite intense. It was concluded that turbulence was anisotropic. In inner vortex flow, near the discharge port and near the inlet of outlet tube, the distributions of Reynolds shear stress increased sharply. The distribution of turbulent viscosity coefficient also reflected this feature.

The turbulence properties of annular space in a cyclone were investigated by using the Laser Doppler Velocimetry.In annular space, the values of tangential, axial and radial turbulence intensity were of the same order of magnitude.In some areas, such as the entrance of annular space, vicinity of the roof of annular space,vicinity of the wall, the distributions of turbulence intensity varied sharply, and turbulence was strongly anisotropic.

Packing density is one of the main factors affecting mass transfer performance of hollow fiber dialyzers. In literature,the conclusions about the effect of packing density on mass transfer coefficient are inconsistent, which probably is due to the ignored effect of module wall and hollow fiber interaction. One standpoint is that with increasing packing density, mass transfer coefficient first increases and then decreases,and another is just the contrary.In this paper, the effect of module wall and hollow fiber interaction is taken into account, and by means of numerical simulation the variation of mass transfer coefficient is studied with hollow fiber packing density increasing from 27.18% to 67.11%. At the same time the effect of flow velocity on mass transfer coefficient is investigated. The results show that with increasing packing density mass transfer coefficient first increases, and then decreases.The flow velocity affects not only mass transfer coefficient (the faster the velocity, the bigger the mass transfer coefficient), but also the optimal packing density corresponding to maximal mass transfer coefficient (the faster the velocity, the bigger the optimal packing density).The results are very significant for designers to improve dialyzers.

The quasi-steady state model of temperature profile for the reverse flow reactor with catalytic combustion of air contaminated with volatile organic compounds (VOCs), is developed by RBF (radial basis function) neural networks. The deep knowledge repository of temperature profile is yielded based on a large number of numerical solutions of the determinant mathematical model, which increases the “extrapolative ability” and “reliability”. Simulation results have proved that the model presented in this paper is simple, highly accurate and can satisfy the prediction requirements.

Synergetic analysis was used for modeling complex reaction kinetics.The synthesis of ethyl tert-amyl ether(TAEE) was chosen as a model system.tert-Amyl alcohol and ethanol were raw materials, and the strong acid cationic exchange resin NKC-29 was used as catalysts.The experiments were carried out in liquid phase under atmospheric condition, and temperature range was from 313 K to 323 K. Haken’s formulations were obtained by a non-singularity transformation of the reaction rate differential equations. Using the adiabatic elimination method, the evolutional relations of reaction order parameters could be obtained. The proposed method avoided solving the complex kinetics differential equations and reduced the number of parameters.Variance analysis proved that the calculated results of the synergetic method agreed well with the experimental results.The values of reaction activation energy were also in a reasonable range.

Supported palladium phthalocyanine was found to be an interesting catalyst with good catalytic stability for selective conversion of CCl₂F₂ into CH₂F₂. Particularly, supported palladium phthalocyanine exhibited excellent stability even at low H₂/CCl₂F₂ ratio in the corrosive reaction conditions due to the formation of HCl and HF. Relatively high selectivities towards CH₂F₂ formation (>75%) over palladium phthalocyanine catalysts with fluoride supports were achieved. The fractionally reduced palladium in palladium phthalocyanine was suggested to be the main active site for catalytic hydrodechlorination.

The liquid-phase dehydration of tert-butyl alcohol to isobutene and water was researched in a reactive distillation column with a catalyst-bed filled with cation exchange resin S-54 in pellet form. A mathematical model for simulating the steady-state characteristics of this process was developed based on the experimental results. The rapid solution for this model can be obtained by the modified overrelaxation method and simulation results agreed well with the experimenal data. The effects of feed flow rates, feed composition, feed location and reflux ratio on reaction conversion were investigated by program simulation. It can be concluded that dehydration of tert-butyl alcohol was facilitated by avoiding strong inhibition of water via reactive distillation.Various heat sources at a lower temperature level below 373K can be transformed to a higher level heat by adjusting the operation pressure. All these support the applicability of this reaction system to a chemical heat pump.

There are some difficulties when traditional genetic algorithm is used to solve multi-objective optimization. Therefore,a newly developed multi-agent technique is introduced to solve multi-objective optimization,and is combined with genetic algorithm to form evolutional multi-agent. Evolutional multi-agent system frame and evolutional genetic algorithm are mainly discussed in this paper.

Due to easy modeling and good robust properties of non-parametric model predictive control based on the step response of a process,it is extensively used in process control. However, the superfluous parameters of non-parametric model predictive control lead to heavy computational burden in the computation of process predictive output and online receding horizon optimization. To overcome the above demerits of non-parametric model predictive control, on the basis of step response of a process, the constrained model predictive control algorithm with redundant parameters is presented in this paper by employing a model with a few redundant parameters to approach the step response of the process. Because of far fewer parameters of the redundant-parameter model than the non-parametric model, the computational burden of multi-step prediction and online receding horizon optimization is relieved greatly. To effectively overcome the adverse influence of modeling errors, a PID feedback correction scheme is introduced. The effectiveness of the presented approaches is verified through computer simulations employing step response data collected from a heat exchanger.

A model to describe the motion of contact line and dynamic contact angle on rough solid surfaces was proposed. It was assumed that a precursor film exists ahead the apparent contact line (ACL) at small velocities of ACL or capillary numbers. The ACL moves on the “wetted” solid surface, rather than “dry” solid surface as expected in the conventional hydrodynamic theories. With introduction of the contact line characteristic parameter, λ′, describing the slipping degree of ACL on the precursor film, the relationship between the dynamic contact angle and the velocity of moving contact line were derived. The comparison of the experimental results with the model indicates the dimensionless characteristic parameter, λ, can describe very well the effect of the solid material and surface properties (roughness etc.) on dynamic wetting processes, and is independent of liquid properties. The difference of static contact angles measured by the dynamic measurement technique from static measurement technique was interpreted by this model and the previous hysteresis tension model.

On the basis of numerical simulation of flow induced corrosion of carbon steel in two-phase flow, the flow induced corrosion of duplex stainless steel in liquid-particle two-phase in-pipe flow was numerically studied. The results showed that, by numerically simulating liquid-particle two-phase flow kinetic process and duplex stainless steel corrosion kinetics, the corrosion rates of duplex stainless steel were computed and the numerical corrosion rates were well in agreement with measured ones. This illustrates that the established corrosion overall model for duplex stainless steel in two-phase fluid is correct and at the same time its flow induced corrosion mechanism is uncovered and verified by tests. The presence of particle phase in fluid greatly strengthens hydrodynamic factor,leading to faster mass transfer process in passive film of duplex stainless steel than liquid single-phase, and causing serious erosion-corrosion. The modeled results also show that the ability to simulate corrosion of materials with surface passive film to some extent depends on their corrosion kinetics process tested by experiments.

In this study，a series of Cu/Co nanomultilayers with the wavelength from 200nm to 5nm were prepared by using single-bath methods and the multilayered structure was studied by using SEM and XRD. The relationship between giant magnetoresistance (GMR) and wavelength(λ) and Cu layer thickness（δC_u） of the multilayer was investigated by using four point probe technique.When λ was rather big，no GMR effect was found.When λ was smaller than 30nm，GMR increased with the decrease of λ，but when λ was smaller than 8nm，GMR vibrated periodically with the change of Cu layer thickness.

The initial start-up of anaerobic biochemical reactor may spend many months even a year to develop granular biomass,which is regarded as a obstacle affecting widespread application of anaerobic process.Self-immobilization of microbes in anaerobic biochemical reactor may be effectively enhanced by adding proper polymers during the period of initial start-up.The characteristics,dose and way of addition showed significant influences on the methane-generating activity, and settling performance of anaerobic microbes. The objectives of this study are to evaluate the feasibility of decreasing the overall time required to form sludge granules with the aid of adding polyquatemary salt into anaerobic biochemical reactor,to determine the optimum way of addition and to quantify the dose.Sixteen biochemical reactors were seeded with anaerobically digested biosolids. Anaerobic biodegradability of polyquatemary salt was measured by the method of biochemical methane potential(BMP).The effects of polyquatemary salt at different concentrations on special methane-generating activity(SMA) of anaerobic microbes were investigated by using anaerobic toxicity assay(ATA).The results showed that polyquatemary salt can exert a positive impact on self-immobilization of anaerobic microbes.The highest SMA of anaerobic microbes appeared at 5—10mg•L^-1(polyquatemary salt concentration).The settling performance of sludge increased as polyquatemary salt dosage was increaced, but the phenomenon of sludge floating occurred at 30—40mg•L^-1. It was recommended that polyquatemary salt was added into anaerobic biochemical reactor during start-up at 9—10d intervals and the most optimum concentration for the granulation was from 10 to 20mg•L^-1.

The synthesis of 2-ethylhexyl palmitate by immobilized lipase candida sp. 99-125 was investigated.The lipase was immobilized on fiber membrane by adsorption. The conditions of enzymatic synthesis of 2-ethylhexyl palmitate were optimized. In the reaction system composed of 1g palmitic acid, 0.67g 2-ethyl hexanol, 5ml petroleum ether and 0.12g (1000IU) immobilized lipase ,shaken in a 50ml conical flask at 40℃ for 24h,the esterification rate reached 97%. The reuse stability of immobilized lipase was about 9 batch.

TiO₂ thin film electrodes were prepared by dip-coating technique. Using the porous nickel based TiO₂ thin film electrode as working electrode, the photoelectrocatalytic system with three kinds of electrodes (working electrode, counter electrode and reference electrode)was built.The effects of pH, initial phenol concentration, quantity of catalyst, intensity of incident light, voltage of electrical bias applied on the photoelectrocatalytic reaction rate of phenol were investigated. The global kinetics was described by an exponential equation derived as C=C₀exp(－0.5430 C ^－0.4241 ₀ E ^0.2968 Q ^0.5418 I ^0.5877 t).The deviation between calculated and experimental results was approximately within 15%.

A series of FE activators were used to intensify Daqing crude oil distillation, which demonstrated that the yield of diesel could be substantially enhanced with activator FE3. From simple distillation, the yield of gasoline was hardly changed while that of diesel could be increased by about 1.0%.In TBP distillation, although no obvious increment was observed for the yield of gasoline, but the yield of light diesel could even be increased by more than 2.0%. Furthermore,diesel was obviously upgraded by this process while gasoline did not deteriorate.

A series of thermo-responsive gating membranes, with a wide range of grafting yields, were prepared by grafting poly(N-isopropylacrylamide)(PNIPAM) onto porous polyvinylidene fluoride (PVDF) membrane substrates with a plasma-induced pore-filling polymerization method. The effect of grafting yield on gating characteristics of thermo-responsive gating membranes was investigated systematically. The results showed that the grafting yield heavily affected water flux,responsiveness coefficient and thermo-responsive gating factor of membrane pore size. When the grafting yield was smaller than 2.81%, both responsiveness coefficient and thermo-responsive gating factor of pore size increased with increasing grafting yield; however, when the grafting yield was higher than 6.38%, both responsiveness coefficient and thermo-responsive gating factor of membrane pore size were always equal to 1, i.e., no gating characteristics existed. In order to obtain a satisfactory gating property of the membrane, the grafting yield must be kept in a proper range.

The plastic injection molding is known to be the most effective process for producing discrete plastic parts of complex shape to the highest precision at a low cost. And the placement of a gate in an injection mold is one of the most important variables of the total mold design, because it influences the manner in which the plastic flows into the mold cavity. In the present paper,some detrimental factors that affect the product quality are assessed.Such assessment can be obtained from numerical simulation results, and can construct a gate location optimization problem. A genetic algorithm is used to search the optimum gate design. The examples indicate that the described methodology can be used effectively to obtain the optimum gate design of single-gate and multi-gate mold.

The research, by means of thermal analysis, on the pyrolytic reaction of fire coatings added with LL fire retardant is presented in this paper. It is also introduced that all the characteristic parameters of the pyrolytic reaction can be reproduced in accordance with the TG curve and that the apparent activation energy of the pyrolytic reaction can be obtained according to the dynamics of pyrolytic reaction of fire coatings.The relationship between the properties of heat absorption and foamed carbonization layer during the reaction and the properties of fire retardancy and heat insulation of fire coatings are analyzed in order to provide information for the development of intumescent fire coatings of high efficiency and superior quality in the future.

Numerical study of two-dimensional isothermal bi-component co-extrusion under wall slip boundary conditions was performed by using POLYFLOW package.The distributions of velocity, pressure, viscosity and shear rate for co-extrusion flow field were solved, with and without the same wall slip coefficients on both wall sides respectively.The effects of wall slip on co-extrusion flow field, interface shape and extrudate swell were discussed. The simulation results revealed that, when wall slip coefficients were kept the same on both wall sides, both interface shift and extrudate swell ratio increased with slip coefficients; when wall slip coefficients were different on both wall sides, interface shift became more significant as the difference of slip coefficients increased, and the melt with a smaller slip coefficient swelled more evidently.

The effect of species, level and procedure of adding organic siloxane, content of hydrolyzation inhibiter, pH value and partition of composite emulsifier between nucleus and shell on the stability of acrylate emulsion was studied. The result showed that using hindering organic siloxane monomer with isopropoxy, adjusting the pH value in the range of 4.5—7, adding the right amount of hydrolyzation inhibitor, and taking post addition of organic siloxane can decrease the degree of hydrolyzation and fasculation, improve polymerization stability and increase the graft ratio and content of organic siloxane, and hence obtain an emulsion with good performance.

Solubilities and properties (density, conductivity and pH value) of solutions in the quaternary system Li⁺,K⁺//CO^2-₃,B₄O^2-₇-H₂O at 288 K were experimentally studied with the isothermal equilibrium method. The phase diagram of the system consisted of two invariant points E and F, five univariant curves, and four crystallization fields that belonged to K₂CO₃·3/2H₂O，Li₂B₄O₇·3H₂O，K₂B₄O₇·4H₂O and Li₂CO₃. The composition of the solution corresponding to E was w（CO^2-₃）=2.27 %，w（B₄O^2-₇）=6.05 %，w（K⁺ ）=4.30%，w(Li⁺)=0.30 % and the equilibrium solids were Li₂B₄O₇· 3H₂O+K ₂B₄O₇·4H₂O+Li₂CO₃;The composition of the solution for F was w(CO^2-₃)=22.45%，w(B₄O^2-₇)=1.88%，w(K⁺ )=29.96%，w(Li⁺ )=0.03% and the equilibrium solids were K₂CO₃·3/2H₂O+K ₂B₄O₇·4H₂O+Li₂CO₃. K₂CO₃ possesses strong salting-out effect on K₂B₄O₇,Li₂CO₃ and Li₂B₄O₇.

Foam fracturing is an important technology in the development of low permeability oil/gas reservoirs. The heat transfer characteristics of foam fracturing fluid are directly relevant to the calculation of pressure drop in the well, the optimum choice of fracturing parameters and the accurate evaluation of fracturing results. CO₂ foam fracturing fluid behaves as a non-Newtonian fluid. The convective heat transfer characteristics of CO₂ foam fracturing fluid were experimentally investigated on the newly constructed large-scale test loop under downhole conditions with CO₂ in supercritical state, the pressure up to 40MPa. From the test data, corresponding correlations for convective heat transfer were obtained and the influences of pressure, temperature and flow rate were also studied. The convective heat transfer coefficient increased with the increase of temperature and flow rate, while the effect of pressure was much more complicated.In most cases, with the increase of pressure the coefficient tended to decrease.

Mathematic model for thermal performance of heat pipe heat exchanger based on the heat transfer model was presented.The infinite volume model was used to calculate the overall thermal performance and the temperature field of heat pipe heat exchanger. The calculation results essentially coincided with the results of an engineering case and provided the theoretical base for engineering application.

Based on the multi-class bubble model and the assumption that bubbles rise in plug flow during dynamic gas disengagement, the function between gas holdup and time was obtained by using the pressure transducing technology. The plot obtained by the model agreed with the plot obtained by experiment. The pressure transducing technology is shown to be a good method for the measurement of hydrodynamics in a bubble column. The changes of gas holdup, large bubble holdup and small bubble holdup, bubble rising velocity with superficial gas velocity and liquid viscosity were obtained by using dynamic gas disengagement.

Droplet spatial distribution is the basic information for the calculation of pressure drop and void fraction of gas-liquid two-phase flow. Based on a detailed analysis of the forces acting on the entrained droplets, one method taking account of the correction of droplet terminal settling velocity due to shear lift force was proposed to modify the droplet turbulent diffusion model. By such a modification the calculated errors of decay coefficient for horizontal oil/gas two-phase separated flow was reduced greatly. As a result, the lift force is one of the important factors to be considered reasonably during the study of droplet diffusion and spatial distribution for oil/gas transport.

Alkylation of methylnaphthalene with methanol is one promising technology for producing 2,6-dimethylnaphthalene. When the alkylation is carried out under ambient pressure by using HZMS-5 catalysis, the reaction activity is very low and obvious deactivation of catalyst is observed in a short run.This paper aims at slowing down catalyst deactivation and improving reaction activity of alkylation of methylnaphthalene with methanol by taking advantage of some special properties of supercritical fluids, such as higher solubility than gases and higher diffusivity than liquids. The results indicate that the reaction under supercritical condition will achieve high reaction activity and long catalyst life. When the reaction was carried out at 460℃ and 7.0MPa which is above the critical temperature and pressure of the inert reaction solvent,1,3,5-trimethylbenzene, the reaction activity increased by 3 times and catalyst life was extended by 25 to 30 times than those under ambient pressure and at the same temperature.

A new membrane electrolyte assembly (MEA) preparation method for polymer electrolyte membrane fuel cell (PEMFC) was developed by applying the directly printing catalyst on membrane technique.This method was simple and easy to be controlled as verified by repetition experiment. When the membrane with catalyst prepared by the new technique and the electrode with diffusion layer was only sandwiched but not hot pressed, this kind of MEA was called not-hot-press MEA (NPMEA) and its fuel cell performance was better than that of MEA which was hot pressed (HPMEA).The effects of 6 different kinds of solvents in catalyst mixture ink on the performance of fuel cell were assessed.It was discovered that iso-propanol was the best solvent in catalyst mixture ink and showed the best performance of fuel cell. Finally several MEAs prepared by different ways were tested on fuel cell station and it was reported that the performance of MEA prepared by the directly printing catalyst on membrane technique was the best in the whole voltage region.

Production and accumulation of toxic by-products such as acetic acid can inhibit the growth of recombinant cells and the expression of
exogenous gene in E.coli.An anionic exchange resin, A-D3-1, which is high in adsorption selectivity and capability for acetic acid, was screened from a variety of resins based on its physical and chemical properties.On the scale of shake flask culture, the addition of 1.0g resin per 30ml medium was insignificant for the cell growth, however,it could improve the hEGF expression significantly. The batch culture in 2.5L fermentor showed that in-situ adsorption of acetic acid by anionic exchange resin could enhance the expression level of interested protein and reduce the fermentation period by 2 hours. And up to 10％ improvement of hEGF (human epidermal growth factor)volumetric productivity (225.0mg•L^-1) could be achieved by supplementing 3.3g resin per 100ml medium.

By using ion-exchange preparative chromatography (IEPC) and reversed-phase high performance liquid preparative chromatography(RP-HPLPC), thymosin α1 was isolated and purified from the crude product synthesized by the solid-phase peptide synthesis(SPPS) method. The purity of the final product reached 95% through ion-exchange chromatography on DEAE Sepharose Fast Flow chromatography and Delta-Pak^TM C18 purification after optimizing the chromatographic conditions. The capacity of purification process was 50mg/circle. The total yield was 36%. The technology is simple and reliable, and can be scaled up easily.

Using the fundamental adsorption equilibrium and kinetic parameters obtained from batch experiments, the mass transport and hydrodynamic behavior in the expanded bed of DEAE Spherodex M was analyzed with the breakthrough model. The results showed that the effect of particle size on breakthrough behavior was obviously greater than that of other parameters.The change of the time of 5% breakthrough, with increasing and decreasing mean particle diameter by a factor of 2, reached about 40% relative to that with the mean diameter, 88 μm. Secondary effects on expanded bed adsorption were film mass transfer and pore diffusion (<10%). Axial dispersion in solid phase had almost negligible effect on the adsorption process. Therefore, the assumption of even dispersion of adsorbent within the expanded bed may result in the model discrepancy to a great extent. It is considered that the breakthrough model can be further improved by taking into account particle size distribution in the expanded bed.

This paper focuses on the research of the bioconversion of 1,3-propanediol by Klebsiella pneumoniae. The linear correlation of cell growth and 1,3-propanediol synthesis was found. An equation of the relationship between cell growth and biocatalysis was given.With the analysis of metabolism, it was discovered that the cell regulated the NADH production by cell growth in order to supply enough reductive equivalent for enzyme catalysis. A conclusion was drawn that the cell growth was coupled with the reactivation of a key-enzyme which catalyzes 1,3-propanediol production in Klebsiella pneumoniae.