Usually，in chemical process，the products are obtained through multi-step chemical reactions.Integration of the multi-step reactions is a matter of great importance for saving energy，improving utilization of resource and cutting down the emission.In this paper，based on the combination scale of the different catalytic active sites，the integrated system，which is composed of several catalytic reactions，is divided into three sub-systems：nano-scale，micro-scale and macro-scale.The typical examples are discussed separately.It was considered that the multi-functional catalysts，in which the active sites were combined in nano/micro scale，was one of the promising methods for the integration of multi-step chemical reactions.

The first part of this paper explains the concept of exergy and gives calculation procedures of exergy by equation of state (PR) and some technical details.It also analyzes the obscure concept of “negative exergy” caused by low pressure, especially when the condition “vacuum” is taken into consideration, showing that like the exergy at a low temperature, “negative exergy” is another valuable kind of exergy.The last part of the paper contains exergy analysis reports about two important chemical processes, rectification and heat exchange with the support of the “three layers” theory.The research indicates that energy-saving in the process of rectification is a specific case study instead of adjusting reflux ratio only.In the process of heat exchange, the pressure exergy loss should be specially chosen as well as heat exergy loss to save expensive high level exergy—electricity.

Ferulic acid was obtained from rice hull with the microwave-assisted extraction method.The solubility data of trans-ferulic acid in 8 binary systems of water and organic solvents, such as methyl acetate, ethyl acetate, butyl acetate, methanol, ethanol, dichloromethane and chloroform were measured from 273.15 K to 333.15 K.The empirical equation was adopted, and the solubilities calculated by the model were in good agreement with experimental data.

An experimental study on the performance of boiling heat transfer of R134a outside a single horizontal tube was conducted for four doubly-enhanced tubes (E10, E11, E12, E15) with different geometries at saturation temperature of 8℃.Experimental results showed that the studied tubes could effectively enhance heat transfer.The overall heat transfer coefficients of the tube E12 were higher than that of the others, and its enhancement factors, the boiling heat transfer coefficient relative to that of Cooper solutions for smooth surface, varied from 2.23 to 2.71, with an average value of 2.54.Because of the different thermodynamic properties, the boiling heat transfer coefficients of R22 were 20%—40% higher than those of R134a.The enhancement factor of boiling heat transfer was independent of refrigerant.

To reveal the features of flow structure and heat transfer and the mechanism of the non-Boussinesq liquid flow driven by thermal buoyancy in cavities, the natural convection of water in square and rectangular enclosures was numerically simulated with CFD software of Fluent.The effects of aspect ratio of the cavity, Rayleigh number, inclination angle and temperature difference between the two walls of the cavity on the flow and heat transfer were investigated.The results show that the flow pattern inverses if the two walls temperature of the cavity was greater and less than 3.98℃，respectively， at which the water density is maximum.The flow pattern inversion has a double vortex structure and decreases the average Nusselt number of natural convective heat transfer.At a fixed Rayleigh number, the average Nusselt number reaches a maximum in the square cavity at the aspect ratio of 1.The inclination of the square cavity has more complex influence on the average Nusselt number which depends not only on the Rayleigh number but also on the thermal boundary conditions.

In the inner wall of aluminium microchannel, super-hydrophobic surface was fabricated.The water contact angle on the surface reached 153°.The pressure drop of water flowing in a 0.60 mm-diameter super-hydrophobic microchannel evidently decreased compared with that in super-hydrophilic microchannel, with the maximal decrease of about 25%.The flow characteristics of water in the microchannel with super-hydrophobic surface were studied.It was found that the critical Reynolds number for the transition from laminar flow to turbulent flow was approximately 2500 and in laminar flow the values of fRe were almost constant.The slip velocity and the slip length were calculated at different flow rates and the results showed that both the slip velocity and slip length increased with increasing water flow rate.

Experiments were performed to study the cycling characteristics of varying working conditions of zeotropic refrigerants in air conditioning systems and to reveal the relationship among cycling parameters, temperature and flow rate of heat transfer fluids in condenser.Based on the experimental data, it was found that the coefficient of performance (COP) increased at the start and decreased at the end with gradually increasing flow rates of heat transfer fluids and the temperature at the condenser inlet unchanged.An assumption about the incomplete condensation of refrigerants was made to explain this phenomenon and the criterion of incomplete condensation was established.According to this criterion, the conditions of incomplete condensation of 15 commercialized zeotropic refrigerants were predicted.

Wine fermentation has a large amount of heat release in the fermentation course.One of the most important measures is to control the temperature effectively to get high quality wine.In this study, an experimental study of the heat characteristics in wine fermentation was made.Firstly, wild fermentation without temperature control was observed, and the heat release of wine fermentation was investigated.This heat release was defined as the inner heat source of wine fermentation.Then, the experiment with temperature control was made.With the consideration of the inner heat source investigated formerly, the unsteady heat transfer was analyzed, and the expression of temperature distributions for wine fermentation was obtained.The results from computer calculation agreed with the experimental results.

The flow behavior of bubble and particles in a gas-solid bubbling fluidized bed was simulated by using a two-fluid model incorporating the effect of particle rotations based on the kinetic theory for rapid granular flow of slightly frictional spheres.A simplified model was implemented without changing the current kinetic theory framework by introducing an effective coefficient of restitution to account for additional energy dissipation due to frictional collisions.Simulations were performed to study the bubble dynamics in a bubbling gas-fluidized bed without and with the consideration of particle rotations.With particle rotation，bubbles were easily formed in the bed，the particle concentrations decreased，and the bed expansion increased.Simulated results indicated that the axial velocities of particles increased，and the translational granular temperature of particles decreased in comparison with the case without particle rotation in the center regime of bed.It was found that the present model with particle rotations better captures the bubble dynamics and time-averaged bed behavior.With the consideration of the effect of particle rotations，the simulated axial velocities and fluctuating velocities of particles were in agreement with literature，and the predicted bubble diameters were close to the calculated results from literatures.

The lattice Boltzmann method（LBM）is an alternative kinetic-based approach in solving various hydrodynamics systems.The LBGK（lattice Bhatnagar-Gross-Krook）model of lattice Boltzmann method，including second-order boundary condition treatment for curve geometry was used to investigate the flow around a single particle.The evolution of vortex structure was analyzed to obtain the reasonable results at both steady and unsteady flows around the single particle.The drag coefficient is a key parameter in the analysis of particle-fluid complex systems，especially，in gas-solids fluidized bed.The drag coefficient was evaluated by using the momentum-exchange method over the range from Reynolds numbers 0.1 to 200，and the results agreed well with the standard equations or the published references.Moreover，this paper gives a new drag relationship based on LBM by using the least squares curve fitting method.Computational results indicate that LBM is an accurate and robust method for drag coefficient simulation.The simulated drag coefficient is more convenient and economical than that obtained by experiment.

The hydrodynamics of an interconnected fluidized bed (circulating bed and spouted bed) with CaSO₄ oxygen carriers (d_p= 0.6 mm) was investigated experimentally.Based on vertical pressure distribution, two zones of different flow regimes (bubbling zone and fast fluidization zone) in the circulating bed (air reactor) and three zones of different flow regimes (spouting zone, bubbling zone, and freeboard) in the spouted bed (fuel reactor) were found to exist.The effects of fluidizing and spouting gas velocities on gas leakage, solids circulating rate and pressure drop were studied.On the basis of experiments, reasonable operation parameters were recommended, which can be used as a reference for further study.

Taking pulverized coal and dry air as the experimental materials, the flow properties of high-concentration gas-solids two-phase flow in an industrial scale horizontal stainless steel tube (I.D.39 mm) were studied.The main flow pattern was identified as stratified flow observed through a quartz glass tube.The test results indicated that the conveying characteristics were dependent on the relationship of the fluidizing gas and adjustment gas.Based on the comparison of test results of two conveying tubes (39 mm and 20 mm in diameter), some empirical expressions relating the larger tube’s operating parameters, including system pressure, gas volume flow rate and solid mass flow rate, were presented.Comparisons of the two conveying tube’s phase-diagrams showed: the mass flow rate of pulverized coal in the larger tube was affected by the system pressure more strongly than that in the smaller one; the larger tube had a higher superficial gas velocity at the pressure drop minimum point and a lower pressure drop if the solids mass flux rate was constant; and the change of pressure drop was less remarkably triggered by the change of solids mass flux rate.

The relationship between pressure drop and channel opening angle of structured packing was studied in order to develop a new approach to intensifying the traditional structured packing.The overall dry-bed pressure drop could be divided into three different parts, which were caused, respectively, by the gas-gas collision in the crisscross junction, the direction change in the interlayer junction, and the drag near the wall zones.The computational fluid dynamics (CFD)software was used to calculate these three kinds of pressure drop.It was shown from the results that the dry-bed pressure drop could decrease significantly when the channel opening angle decreased from traditional about 90° to 20°.The CFD simulations were consistent with the experimental data.

Based on the experimental results of micro-bubble controlled growth in MEMS(micro-electro-mechanical system) devices，the bubble growth process could be divided into four stages，namely，nucleating，spherical bubble，bubble restrained by lateral wall，bubble elongating along the channel.A physical model of micro-bubble growth in the rectangular microchannel was established by considering the micro layer of liquid in the heater.Numerical simulation of micro-bubble growth in the micro restrained space was performed by the Level Set Method and the characteristics of micro-bubble growth were obtained and analyzed.The simulated data showed that micro-bubble grew rapidly in the early stage but grew slowly in the late stage due to the increasing condensation rate on the interface.The results also indicated that the initial temperature of liquid，width of the microchannel，width of the microheater，and the heating voltage had remarkable effects on the bubble inception and bubble growth rate.

Quartzite particles, as a bed material, are used in the high density fluidized bed.However, in the operation, a great amount of fines, due to the attrition of quartzite particles, were elutriated, which would result in the decrease of bed material and bed pressure drop, and herein have an impact on the normal fluidization in the fluidized bed.In view of the attrition of quartzite particles, a mathematic model was established based on the Fleischer’s system energy balance theory about the friction attrition mechanism.The condition that the fine particles were separated from the parent particles was based on the least energy principle of material dynamic failure.The particle’s operation characteristics in the fluidized bed and the particle’s physical properties were also considered in the model.This model could explain some factors of the particle’s attrition.Moreover, the predicted value from the model was close to the experimental value.Therefore, this study would be beneficial to the engineering application of the high density fluidized bed.

o-Nitrobenzaldehyde (ONBD) is an important intermediate for preparing medicine and fine chemicals.But there are serious problems in present industrial production methods, such as environmental pollution, equipment corrosion, and high energy consumption.A novel green synthesis of o-nitrobenzaldehyde by dioxygen oxidation of o-nitrotoluene (ONT) with metal porphyrins as catalysts was investigated in order to solve the above problems.The results showed that conversion of o-nitrotoluene was up to 47.8%, and the maximum selectivity and yield of o-nitrobenzaldehyde were 54.2% and 25.9% respectively under the optimum conditions: 2.0×10 ^-6mol·L^-1 of T(o-Cl)PPZn catalyst, 5.0 mol·L^-1of NaOH concentration, and 40℃, 1.5 MPa for 4 h.The effects of center metal ions and substituents as well as their positions in the ring of porphyrin on the activity and selectivity of the above reaction were also studied, and the results showed that center metal ions and substituents as well as their positions in the ring of porphyrin had very different effects on the activity and selectivity of such a reaction.

Titanium dioxide nanotubes were prepared by the hydrothemeral method, and characterized with TEM, XRD and BET.The anatase products, with an external diameter of 5—7 nm, a wall thickness of about 1 nm and a length of 200—300 nm, had a specific surface area of 276 m²·g^-1.Their adsorption of COD, catalytic activity and reaction kinetics for ozonation in landfill leachate solution were studied.The removal rate of COD by using O₃/UV/TiO₂ nanotubes in 60 minutes was 20.83% better than using O₃/UV/P25 (Degussa, Germany), and 32.65% better than using O₃/UV (Yingze Corp., China).In landfill leachate solution, the maximal absorption of COD on 0.5 g TiO₂ nanotubes, contributing 10.14% of the total COD removal rate, was 1.34 times as that on 0.5 g P25 at 293 K.The overall apparent rate constant of O₃/UV/TiO₂ nanotubes was 1.19 times as that of O₃/UV/P25, and 1.80 times as that of O₃/UV in 2 hours.Two equations between k and T were obtained, and the total apparent activation energy of O₃/UV/TiO₂ nanotubes was 2.925 kJ·mol^-1 less than that of O₃/UV/P25.

Mg₂NiH₄ was prepared by the replacement-diffusion method，and its structure was characterized with SEM，XRD and DSC.Mg₂NiH₄ had high purity，a great deal of crackle on the surface，and high activity.Its hydrogen-storage capacity was 3.6% and affranchising hydrogen temperature was 292.4℃.DSC results showed that Mg₂NiH₄ had good catalytic effect on the thermal decomposition of ammonium perchlorate（AP）.When the content of Mg₂NiH₄ reached 10%(mass)，the high temperature exothermic peak of AP was decreased by 108.2℃ and the exothermic heat increased by 217.0％.Meanwhile，the catalysis mechanism was discussed.

The start-up and operational features of anaerobic ammonium oxidation（ANAMMOX）process were investigated comparatively in two 3.2 L upflow anaerobic sludge blanket（UASB）reactors，which both were fed with artificial waste-water composed of NH⁺⁴-N and NO^-2-N at a proper ratio.The results showed that the removal efficiencies of NH⁺⁴-N and NO^-2-N were 99.7% and 99.9%，respectively，in the No.1 reactor after 220 days; while the removal efficiencies of NH⁺⁴-N and NO^-2-N reached 99.8% and 99.9%，respectively，in the No.2 reactor only after 150 days.The average ratio of removed NH⁺⁴-N，removed NO^-2-N and generated NO^-3-N was 1︰1.16︰0.15 at the stable phase in the No.1 reactor，while it was 1︰1.28︰0.15 at the stable phase in the No.2 reactor.The pH value had characteristic change in both reactors.The black activated sludge changed to yellow granular sludge in both reactors gradually.With the extension of time，the shock resistance of volume load was growing stronger and stronger in both reactors.Furthermore，UASB-ANAMMOX reactor with biofilm had the advantage of bacterial immobilization and keeping bacterial amount.

Fe₃O₄ catalyst supported on spherical γ-Al₂O₃ was prepared with and without ultrasonic treatment during the impregnation step, and the heterogeneous catalytic oxidation of dimethoate wastewater was conducted with Fenton reagent.Then, the physical and chemical properties of the catalysts were analyzed by means of XRD, ICP-AES and SEM, especially the effect of Fe₃O₄ dispersity on γ-Al₂O₃.The results showed that the activity of the supported catalysts prepared with ultrasonic treatment for dimethoate was higher than those without ultrasonic treatment and the corresponding degradation rate doubled those of the catalyst obtained by impregnation.The probable cause was that for catalysts prepared with ultrasonic treatment, Fe₃O₄ was well dispersed on the catalyst surface with small particle size, or existed in non-crystalline amorphous state, and Fe content on the catalyst surface was higher than those without ultrasonic treatment.

The effects of reaction time, reaction temperature and acid concentration on xylose concentration in coconut shell hydrolysate were investigated.The acid hydrolysis mechanism for coconut shell was discussed.As a homogeneous irreversible series reactions system, first-order reaction rate models for coconut shell acid hydrolysis were established.The activation energy, kinetic coefficient for xylooligosaccharides hydrolysis and kinetic coefficient for xylose decomposition were estimated.According to the rate equations, the favorable acid hydrolysis conditions were predicted, the drawn conclusions can be used to industrial production.

Plate falling film regenerator with a film-inverting configuration is a new type of regenerator that combines the plate falling film absorption technique with the film-inverting technique.Understanding its performance is very important for industry applications.This paper used a new type regenerator and a plate falling film regenerator for comparison.The design conditions of these two regenerators were the same.By solving the mathematical model，the heat and mass transfer characteristics were calculated and compared between the two regenerators at different flow rates of solution，inlet concentrations，inlet temperatures，generation pressures，and heating conditions.The comparison revealed that these two regenerators had different changes of performance under varying operation conditions.In the case replacing the plate falling film regenerator with the new plate falling film regenerator with film-inverting configuration，the differences in the performance of the regenerators under varying conditions must be taken into consideration.

Non-porous polyether sulfone hollow fibers (with a 5 μm poly (dimethylsiloxane) coating) were used as structured packing in the distillation of ethanol-water solutions.In this novel membrane contactor, liquid flowed through the lumens of the fibers, and vapor flowed countercurrently outside the fibers.The results showed that the new membrane contactor gave better, more productive separations than traditional packing in distillation.The minimal HETP of hollow fibers could reach as low as 5.8 cm, and the contactor worked well above the limit where flooding normally occurs in conventional cases.The overall mass-transfer coefficient and individual mass-transfer coefficients based on the gas side and liquid side were calculated respectively.The theoretical analysis indicated that the resistance in the liquid was responsible for more than half of the total resistance.

A novel combined method based upon nodal test and measurement test (NT-MT) was proposed for gross error detection and steady-state data reconciliation.In NT-MT, nodal test and measurement test were used together to find the suspicious nodes with gross error and to further find the most suspicious measurement variable connected to one of the found suspicious nodes.Then, adjustment test, which was able to consider the known knowledge obtained by expert, was introduced to determine whether the most suspicious measurement variable had gross error or not.This method took advantage of both nodal test and measurement test and overcame their disadvantages.The results of a simulation and an industrial application showed that the proposed method could get accurate results for the system with more than one gross error and was superior to iteration measurement test (IMT).

In order to use the properties of samples, a soft-sensing method with multiple models based on an online clustering arithmetic and v-support vector regression(vSVR) was presented.The parameter selection of vSVR is improved faster and robust by a new cross validation method using the online clustering arithmetic and parameter’s prior knowledge.The proposed soft-sensing method was used to predict the light naphtha end point in hydrocracker fractionators.Practical applications indicated the proposed method was useful for the online prediction of quality specifications in chemical processes.

With the estimation of key quality index in an industrial naphthalene distillation column, a novel soft-sensor modeling method based on Gaussian process（GP）was proposed for complex industrial processes.The principle of automatic relevance determination, implemented with GP model, was proposed to determine the secondary variables for the soft-sensor.To overcome the shortcomings existing in present methods, which can not determine the measurement uncertainty of soft-sensors, the GP based soft-sensor was developed to get both the prediction of key quality index and its measurement uncertainty simultaneously.Application studies showed that the GP soft sensor model not only determined the secondary variable automatically, but also possessed both high accuracy and small measurement uncertainty, which met the demands for reliable measurements in industrial application.

Batch processes are inherently more difficult to model than continuous processes due to their complex dynamics, non-steady-state operation and batch-to-batch variation, especially under new operation condition and with small samples.To improve the generalization performance of the global learning based modeling methods, such as least squares support vector regression (LSSVR), a local LSSVR (LLSSVR) was proposed for modeling batch processes.By combining the optimized parameters of LSSVR from previous batches off-line, an online LLSSVR built a model for each set of new data to be predicted in a new batch by considering only the neighbors of this query.The proposed LLSSVR algorithm was applied to the online prediction of biomass concentration in the penicillin fed-batch process.The simulations showed that LLSSVR could predict the biomass concentration online just from the second batch, which was more accurate and robust to batch-to-batch variation than LSSVR.

A theoretical calculation method of electrokinetic flow in micro equilateral triangle channels imposed with high electric field strength at both ends of channel was proposed based on the Galerkin method.The Poisson-Boltzmann equation and the momentum equation were solved to determine the electric potential field and electrokinetic flow field in micro equilateral triangle channels respectively.The effects of electric field strength，zeta potential，electrolyte concentration，fluid temperature，and micro triangle channel size on the electrokinetic flow behavior were discussed by virtue of the calculated electric potential profile and flow field profile.The mass flux of liquid in micro equilateral triangle channels increased with increasing zeta potential and electric field strength.A larger concentration of electrolyte and higher fluid temperature could lead to a larger mass flux of fluid.The mass flux of fluid firstly increased to a maximum value and then decreased as the size of micro equilateral triangle channel further increased，which implied that there existed a specific channel size corresponding to the maximum fluid mass flux of electrokinetic flow in the micro equilateral triangle channel under the same operation conditions.

Isothermal oxidation and cyclic oxidation behavior of pure and yttrium-implanted nickel was studied at 1000℃ in air.Scanning electronic microscopy（SEM）and transmission electronic microscopy（TEM）were used to examine the morphology and structure of oxide films formed on nickel.It was found that yttrium-implantation greatly improved the anti-oxidation ability of nickel.Acoustic emission（AE）technique was used in situ to monitor the cracking of oxide films in oxidizing and air-cooling stages.Laser Raman spectrometer was also used to study the stress status of oxide scales formed on nickel with and without yttrium.The main reason for the improvement of anti-oxidation of nickel was that yttrium-implantation greatly reduced the growing speed and grain size of NiO，and this fine-grained NiO oxide film might have better high temperature plasticity and could relieve part of compressive stress by means of creeping.In the meantime，yttrium-implantation reduced the size and number of interfacial defects，hence remarkably enhancing the adhesion of protective NiO oxide scale formed on nickel substrate.

Recombinant E.coli malate dehydrogenase (eMDH) was expressed as inclusion bodies (IBs), and the eMDH IBs was used as a real oligomeric protein to study protein refolding from IBs assisted by two major osmolytes, betaine and trehalose.It was observed that the specific activity of eMDH was enhanced by increasing betaine concentration, while there was an optimal trehalose concentration at which the protein was favorably renatured.Furthermore, the renaturation could be improved even at high guanidinium chloride concentrations (up to 0.4 mol·L^-1) in the presence of betaine or trehalose.It was shown by binding of 1-anilino-8-napthalene sulfonic acid (ANS) to eMDH as a function of osmolyte concentration at different guanidinium chloride concentrations that the hydrophobic residue exposure on eMDH surface was reduced in the presence of osmolyte.Circular dichroism (CD) spectra indicated that osmolyte could promote the formation of α-helical in eMDH.

The change of physicochemical properties of wheat starches was studied after microwave irradiation.Wheat starches were treated at a moisture content of 30% by microwave irradiation.The results showed that the surface was porous and a concavity could be clearly observed at the center of starches.Microwave treatment increased the X-ray intensities of the major d-spacings of starches.The swelling power,solubility, syneresis and the enthalpy of gelatinization decreased on this treatment.Microwave treatment increased the gelatinization transition temperatures and the gelatinization temperature range of starches.The rise in pasting temperature and the drop in viscosity of wheat starches were observed after microwave irradiation.However, the viscosity patterns remained unchanged.Associations involving starch chains (amylose-amylose and amylose-amylopectin) with the amorphous and crystalline regions of the granule resulted in the formation of new crystallites of different stabilities and led to more ordered crystalline array.

The emission of submicron particles from coal combustion has caused serious damage to the environment and human health.A novel submicron particle agglomeration technique was developed to control the emission of submicron particle.The submicron particles were agglomerated by an agglomerant solution which was sprayed into the inlet of electrostatic precipitator (ESP), thus, the agglomerated submicron particles could be captured by the dust collecting equipment.Systematic experiments of submicron particle agglomeration were conducted, and the influence factors including pH value, flow rate, and concentration of agglomerant solutions were analyzed.In addition, the influence of temperature and particles concentration in the simulated flue gas was also discussed.With the addition of the agglomerant solution, the particle emission concentration in flue gas decreased significantly.The submicron particles agglomeration technology whose cost is cheaper can control the emissions of submicron particles and decrease the opacity of flue gas obviously without changing the operation parameters of the ESP.The particle agglomeration technique is a useful and promising method to control the emission of submicron particles from coal combustion.

Thermo-gravimetric analysis was performed to study dual peaks of Huadian oil shale combustion and influence on each other by oil shale and semi-coke, particle characteristics, ignition temperature and combustibility index during blended combustion of oil shale and 500℃ semi-coke at the different blended proportions.Blended combustion kinetics was analyzed by using the distributed activation energy model (DAEM).The results indicated that dual peaks reactivity parameter of DTG burning profile around 500℃ was 0.79 and 0.73, which suggested that double peaks could be attributed to the combustion of aliphatic components and aromatic moieties in kerogen.The influence on each other was different at different temperature zones.The apparent degree coefficients of mutual influence were less than 1.Four consecutive stages were experienced in shrinking core shape and surface fractal dimension.Shrinking core shape was close to long cylinder at the low temperature zone, close to plate at the high temperature zone.Fractal dimension was near 3 at the low temperature zone, near 1 at the high temperature zone, when concentration level (β) was 0.6. Ignition temperature increased linearly with the increase of semi-coke blended proportion.Blended combustion index exhibited a transition from semi-coke to oil shale, with an evident intermediate zone of mutual influence.The apparent activation energy of samples decreased slowly at the earlier stage between 60 and 90 kJ·mol^-1, but at the latter stage increased strongly from 80 to 200 kJ·mol^-1, while the conversion was from 0.60 to 0.75.

The changes in physical characteristics of rice husk during high speed pyrolysis were examined.The pyrolysis reaction ratios (defined as the ratio of pyrolyzed mass to pyrolyzable mass) of rice husk particles prepared under different conditions were calculated by non-isothermal thermogravimetric analysis.To study the physical characteristics of rice husk/char particles, proximate and ultimate analyses, physical adsorption/desorption measurements of N₂(-196℃), mercury injection porosimetry (414 MPa) as well as visualization by scanning electronic microscopy(SEM) were performed.Appreciable differences in physical characteristics, depending markedly on the pyrolysis stage, were observed.Rough pore surface in char particles was detected clearly by SEM measurement.The release of volatile matter led to the development of pores with different sizes.Progressive increase of micropores developed with the pyrolysis process, whereas a maximum speed of micropore development occurred at the pyrolysis reaction ratio of 0.8.But macropores in char particles had different evolution characteristics.Based on the analysis result of density and porosity data, the particles shrank greatly at the first stage of high speed pyrolysis.

An experimental study was made to understand the role of lecithin in hydrate formation/ stabilization in drilling fluids.The effect of lecithin on the thermodynamics and kinetics of methane hydrate formation/decomposition in pure water was investigated.Experimental results indicated that lecithin did not significantly affect the hydrate thermodynamic equilibrium conditions.Lecithin was however an excellent kinetics promoter as indicated by a significant increase in the rates and amounts of hydrate formation when the concentration of lecithin was over 0.003 g·g^-1.

It is important to achieve short-cut nitrogen removal from municipal wastewater for saving energy and carbon source.However, a low temperature (10—20℃) affects the actual application of short-cut nitrogen removal from wastewater.In this study, a large pilot-scale SBR was used to treat real municipal wastewater.The goal of achieving and stabilizing short-cut nitrification at a low temperature was mainly investigated.The results indicated that through real-time control and step-feed operating pattern, short-cut nitrogen removal with nitrite accumulation rate above 95% and nitrogen removal efficiency above 96% was achieved at 11.8—25℃.The key factor of achieving and stabilizing short-cut nitrification in pilot-scale SBR was the optimization of nitrifying communities in sludge owing to long-term application of real-time control.

Diffusion of microbe plays an important role in microbial restoration of soil and groundwater. For saturated soil, a membrane cell was designed to measure the effective diffusion coefficient.In this study,the theory of fractal dimension was also used to calculate the cell constant of bacteria and the tortuosity factor of soil membrane. In the experiment of KCl diffusion, cell constant of KCl was directly calculated.In the second experiment the model of fractal dimension was used and the cell constant of microbe diffusion was obtained.Using the model of fractal dimension, tortuosity factor was also deduced.The effective diffusion coefficient of bacteria was obtained.

Comprehensive evaluation of effluents is of great importance for environmental impact assessment.In this paper, three kinds of chromeplating effluents were characterized by determining pH, conductivity and COD values.The toxicity of these effluents to Photobacterium phosphoreum was also determined.According to the toxicity category standard, their order of toxicity intensity was obtained.Although there was a correlation between EC₅₀, COD and conductivity to some extent, it was inappropriate to represent quantitatively the damages to organisms only by the physico-chemical properties of the chromeplating effluents.It was indicated that a combination of physico-chemical characterization and comprehensive toxicity analysis could provide the correct information for effluent discharge standards.In this study, causative toxic compound types in three kinds of electroplating effluents were also analyzed preliminarily according to conductivity, COD and EC₅₀ values.It can provide the basis for toxicity identification evaluation of electroplating effluents.

A series of polymeric diols with different comb-branched chains (CPDs) were prepared and characterized by FTIR.The effects of comb-branched structure and temperature on the rheological properties of CPDs were studied.The flow activation energy ΔE_η0 of CPDs was also measured.The results showed that the viscosity of CPDs increased and the shear rate at the beginning of shear thinning behavior decreased with increasing length and polarity of comb-branched chains.Two kinds of shear thinning behavior were shown on the η-γ curves of CPDs.A plateau existed between these two kinds of shear thinning behavior on the η-γ curves of CPDs.The plateau moved toward the high shear rate and shortened with increasing temperature, and disappeared at 50℃.The flow activation energy ΔE_η0 increased with the increase of length and polarity of comb-branched chains.

Nanosized bismuth-doped tin dioxide/waterborne polyurethane nanocomposite materials were prepared by the blending method with self-made nanosized bismuth-doped tin dioxide slurry and waterborne polyurethane as raw materials.Experimental results indicated that the isoelectric point of nanosized bismuth-doped tin dioxide slurry was about pH 6 and the nanosized bismuth-doped tin dioxide was dispersed well with the composite dispersers of siloxane coupling agent of KH-550 and DP-518.The tensile strength and breaking extensibility of nanocomposite film containing 1.0% of the nanosized bismuth-doped tin dioxide were 9.23 MPa and 223%, respectively, and the transmittance of visible light was about 70%.The heat-insulation was over 8℃ in contrast to the pure waterborne polyurethane film.

Poly(ethylene terephthalate)(PET)/SiO₂ nanocomposites were synthesized via the sol-gel method that involved two steps: terephthalic acid first reacted with excess ethylene glycol to form bis(hydroxyethyl) terephthalate (BHET); tetraethoxysilane (TEOS) was added into the BHET, and the sol-gel reactions proceeded at a high temperature to form the silica nanonetwork concurrent with polycondensation of BHET to produce the PET matrix.Transmission electron microscopy (TEM) showed that the sizes of silica particles were at nanoscale, and the nanoparticles were uniformly dispersed in the polymer matrix.Thermogravimetric analysis (TGA) results indicated that the activation energy of thermal degradation of the composites was largely increased.The nonisothermal crystallization ability of the composites was found to decrease according to differential scanning calorimetry (DSC).

Microcrystalline Al₂O₃ ceramic with high purity was prepared by normal pressure sintering and high pressure sintering using superfine alumina powder.The experimental results indicated that high-speed ball milling in ethanol could reduce the average size of Al₂O₃ particles remarkably，and increase the specific surface area and sintering activity of Al₂O₃ powder.Pure Al₂O₃ ceramic with a relative density of 98.71% was fabricated under sintering pressure of 4.5 GPa and at a temperature as low as 1230℃ in 30 min.As compared with normal pressure sintering, the sintering temperature was decreased remarkably in the high pressure sintering process，the velocity of mass transfer was increased and the sintering time was shortened.High pressure sintering could achieve the effect of fast and low-temperature sintering.Because of a relatively low sintering temperature in the high pressure sintering process，liquid phase did not exist in MgO-doped Al₂O₃ ceramic and MgO had no effect on densification and restraint of Al₂O₃ grain growth.

The Si species distribution of inorganic polymer flocculant polyferric silicate sulfate (PFSS) was studied by chemical Si-Mo assay.The study included reaction rate characteristics and standard work curve of SiO₂, polysilicic acid (PSi) species distribution characteristics at different pH values, and comparison of Si species distribution characteristics of PFSS and PSi at different pH values .The experimental results showed that Si species distribution characteristics in PFSS were variable at different pH values.The content of Si_b of silicic acid in PFSS at pH values 1.46 and 1.70 was higher than that of silicic acid in PFSS at pH value 0.64, while the contents of high polymer state and gelatinous state in PFSS at pH value 0.64 were obviously higher than those in PFSS at pH values 1.46 and 1.70.Simultaneously, the study results also showed that PFSS at pH values 1.46 and 1.70 had better flocculability and stability than PFSS at pH value 0.64, therefore the superior state of silicic acid in PFSS was Si_b.

The low heat solid state reaction method for the synthesis of functional material lanthanum phosphate was studied, and the target product was obtained successfully with La(NO₃)₃·6H₂O and (NH₄)₃PO₄·3H₂O as raw materials and PEG-400 as surfactant via the low heat solid state reaction.Crystallization calculated with XRD data of the product was used as the testing index, and application of uniform experimental design as well as data mining technology were used in the test.The synthesis tests were performed under the guidance of the results of data mining technology.The test results indicated that the product synthesized with the optimal technical condition was LaPO₄·0.5H₂O with the size of 23 nm and crystallization of 97.8%.TG/DTA analysis results indicated that LaPO₄ could be obtained from dehydration of LaPO₄·0.5H₂O at 300℃.

The mesoscopic phase of block copolymers PAn-PEG-PAn in aqueous solution was investigated by dissipative particle dynamics (DPD) simulation.The effects of the molar fraction of PAn segment in the copolymers and its concentration on the copolymers’ self-assembling were discussed.The distribution of PEG and PAn segments on the surface of the spherical micelle of the copolymer was interesting but was difficult to observe by experiments.The authors focused on investigating the characteristics of the spherical micelle of the copolymers in a low concentration.There existed two novel core-shell spherical micelles separately with increasing molar fraction of the PAn segment.One was that the PAn segment made up the shell and the PEG segments the core; the other was that the PEG segments made up the shell and the PAn segments the core.A greater part of water was aggregated to form cylindrical and spherical micelles, while the remaining was distributed in the block copolymers symmetrically when the mass fraction of the copolymers was more than 66.7%.DPD simulation could be considered as an assistant for the experimental research and could provide useful information which is difficult to obtain by experiments.