A simple chemical method was employed to coat carbon nanotubes with a layer of copper. Due to the hydrophobic nature, large surface curvature, small diameter and large aspect ratio, it is difficult to gain continuous electroless plating layer on the surface of carbon nanotubes. In this paper, a series methods (oxidization, sensitization and activation) are used to add active sites before electroless plating, and the adjustment of the traditional composition of copper electroless plating bath and operating condition can decelerate electroless plating rate. The samples before and after coating were analyzed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that the surface of carbon nanotubes was successfully coated with continuous layer of copper, which lays a good foundation for applying carbon nanotubes in composites.

Multi-kernel-based support vector machine (SVM) model structure of nonlinear systems and its specific identification method is proposed, which is composed of a SVM with linear kernel function followed in series by a SVM with spline kernel function. With the help of this model, nonlinear model predictive control can be trans-formed to linear model predictive control, and consequently a unified analytical solution of optimal input of multi-step-ahead predictive control is possible to derive. This algorithm does not require online iterative optimiza-tion in order to be suitable for real-time control with less calculation. The simulation results of pH neutralization process and CSTR reactor show the effectiveness and advantages of the presented algorithm.

Biomass is a key factor in fermentation process, directly influencing the performance of the fermentation system as well as the quality and yield of the targeted product. Therefore, the on-line estimation of biomass is indispensable. The soft-sensor based on support vector machine (SVM) for an on-line biomass estimation was analyzed in detail, and the improved SVM called the weighted least squares support vector machine was presented to follow the dynamic feature of fermentation process. The model based on the modified SVM was developed and demonstrated using simulation experiments.

A support vector machine (SVM) with quadratic polynomial kernel function based nonlinear model one-step-ahead predictive controller is presented. The SVM based predictive model is established with black-box identification method. By solving a cubic equation in the feature space, an explicit predictive control law is obtained through the predictive control mechanism. The effect of controller is demonstrated on a recognized benchmark problem and on the control of continuous-stirred tank reactor (CSTR). Simulation results show that SVM with quadratic polynomial kernel function based predictive controller can be well applied to nonlinear systems, with good performance in following reference trajectory as well as in disturbance-rejection.

Octacosanol is purified by agitated short-path distillation (SPD). Effects of evaporation
temperature,number of SPD steps in series and other distillation method on the octacosanol
recovery and decomposition arestudied. Although the experimental results indicate some
decomposition when the mixture of higher primaryaliphatic alcohols is distillated by SPD,
SPD is still an effective method to purify octacosanol. It is concluded thatevaporation
temperature affects greatly on the purity and recovery of octacosanol.

The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater. There was a programmed decrease of the airflow rate to 28L•h－1, the corresponding average dissolved oxygen (DO) was 0.32mg•L－1, and the average nitrite accumulation rate increased to 92.4% in 3 weeks. Subsequently, further increase in the airflow rate to 48L•h－1 did not destroy the partial nitrification to nitrite, with average DO of  0.60mg•L－1 and nitrite accumulating rate of 95.6%. The results showed that limited airflow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction.

The gas-liquid flow field in a stirred tank with a Rushton disk turbine, including the
impeller region,was numerically simulated using the improved inner-outer iterative
procedure. The characteristic features of the stirred tank, such as gas cavity and
accumulation of gas at the two sides of wall baffles, can be captured by the simulation.
The simulated results agree well with available experimental data. Since the improved
inner-outer iterative algorithm demands no empirical formula and experimental data for the
impeller region, and the approach seems generally applicable for simulating gas-liquid
stirred tanks.

Reactive distillation processes for synthesis of ethylene glycol (EG) and ethyl tert-butyl ether (ETBE) were modeled with the simulation package ASPEN PLUS. The input multiplicity and output multiplicity were discussed with the method of sensitivity analysis for both cases. In EG production process, steady state multiplicities were studied in terms of effective liquid holdup volume and boil-up ratio. In ETBE synthesis process, the user kinetic subroutine was supplied into ASPEN PLUS firstly, and then the composition, temperature and reaction-rate profiles within the reactive distillation column were presented in detail. A set of stable solution branches based on distinct initial guesses for a range of boil-up ratio were found in EG synthesis. Input multiplicities were observed for a range of reboiler duty at several values of reflux ratio for ETBE synthesis process. These results can be used to avoid excessive energy consumption and achieve optimum design of reactive distillation column.

Six preparation methods for polymeric organic-inorganic nanocomposites and their respective
mecha-nisms and features are reviewed. The extraordinary properties of polymeric organic-
inorganic nanocomposites arediscussed,and their potential applications are evaluated.

A novel control strategy for a continuous stirred tank reactor (CSTR) system, which has the
typical characteristic of strongly pronounced nonlinearity, multiple operating points, and
a wide operating range, is initiated from the point of hybrid systems. The proposed scheme
makes full use of the modeling power of mixed logical dy-namical (MLD) systems to describe
the highly nonlinear dynamics and multiple operating points in a unified framework as a
hybrid system, and takes advantage of the good control quality of model predictive control
(MPC) to design a controller. Thus, this approach avoids oscillation during switching
between sub-systems, helps to relieve shaking in transition, and augments the stability
robustness of the whole system, and finally achieves optimal (i.e. fast and smooth)
transition between operating points. The simulation results demonstrate that the presented
ap-proach has a satisfactory performance.

Pressure drop and compound heat transfer characteristics of a converging-diverging tube with evenly spaced twisted-tapes (CD-T tube) have been investigated experimentally. Swirl was generated by evenly spaced twisted-tape elements which vary in twist ratio and rotation angle. Space ratio also has an important effect on the characteristics. For comparison, experiments in a smooth circular tube and a converging-diverging (CD) tube with-out twisted-tapes were carried out. The results show that the twisted-tape with twist ratio y＝4.72 and rotation angle θ＝180° has the best performance among the four types of twisted-tapes presented in this paper. At Reynolds num-ber ranging from 3400 to 20000, when space ratio s＝48.6, the heat transfer efficiency index, which increases as the Reynolds number increases, is 0.85—1.21 and 1.07—1.15 compared to that of a smooth circular tube and a CD tube without twisted-tape inserts, respectively.

Based on the Navier-Stokes equations and the Spalart-Allmaras turbulence model, three-dimensional turbulent flow in four low-specific-speed centrifugal impellers are simulated numerically and analyzed. The relative velocity distribution, pressure distribution and static pressure rise at the design point are obtained for the regular impeller with only long blades and three complex impellers with long, mid or short blades. It is found that the back flow region between long-blade pressure side and mid-blade suction side is diminished and is pushed to pressure side of short blades near the outlet of impeller at suction side by the introduction of mid, short blades, and the size of back flow becomes smaller in a multi-blade complex impeller. And the pressure rises uniformly from inlet to outlet in all the impellers. The simulated results show that the complex impeller with long, mid and short blades can improve the velocity distribution and reduce the back flow in the impeller channel. The experimental results show that the back flow in the impeller has an important influence on the performance of pump and a more-blade complex impeller with long, mid and short blades can effectively solve low flow rate instability of the low-specific-speed centrifugal pump.

The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fer-mentation has been commercialized since longer times, the dehydration process of lactic acid is still under devel-opment because of its low yield. Further efforts should be made before this process became economically feasible. Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic en-gineering provides also a possibility to produce acrylic acid directly from biomass by fermentation.

Based on a nonlinear state predictor (NSP) and a strong tracking filter (STF), a sensor
fault tolerant generic model control (FTGMC) approach for a class of nonlinear time-delay
processes is proposed. First, the NSP is introduced, and it is used to extend the
conventional generic model control (GMC) to nonlinear processes with large input time-
delay. Then the STF is adopted to estimate process states and sensor bias, the estimated
sensor bias is used to drive a fault detection logic. When a sensor fault is detected, the
estimated process states by the STF will be used to construct the process output to form a
"soft sensor", which is then used by the NSP (instead of the real outputs) to provide state
predictors. These procedures constitute an active fault tolerant control scheme. Finally,
simulation results of a three-tank-system demonstrate the effectiveness of the proposed
approach.

Based on a nonlinear state predictor (NSP) and a strong tracking filter (STF), a sensor
fault tolerant generic model control (FTGMC) approach for a class of nonlinear time-delay
processes is proposed. First, the NSP is introduced, and it is used to extend the
conventional generic model control (GMC) to nonlinear processes with large input time-
delay. Then the STF is adopted to estimate process states and sensor bias, the estimated
sensor bias is used to drive a fault detection logic. When a sensor fault is detected, the
estimated process states by the STF will be used to construct the process output to form a
"soft sensor", which is then used by the NSP (instead of the real outputs) to provide state
predictors. These procedures constitute an active fault tolerant control scheme. Finally,
simulation results of a three-tank-system demonstrate the effectiveness of the proposed
approach.

Multi-objective optimization of a purified terephthalic acid (PTA) oxidation unit is
carried out in this paper by using a process model that has been proved to describe
industrial process quite well. The model is a semiempirical structured into two series
ideal continuously stirred tank reactor (CSTR) models. The optimal objectives include
maximizing the yield or inlet rate and minimizing the concentration of 4-carboxy-
benzaldhyde, which is the main undesirable intermediate product in the reaction process.
The multi-objective optimization algorithm applied in this study is non-dominated sorting
genetic algorithm Ⅱ (NSGA-Ⅱ). The performance of NSGA-Ⅱ is further illustrated by
application to the title process.

Principal component analysis (PCA) is a useful tool in process fault detection, but offers little support on fault isolation. In this article, structured residual with strong isolation property is introduced. Although it is easy to get the residual by transformation matrix in static process, unfortunately, it becomes hard in dynamic process under control loop. Therefore, partial dynamic PCA(PDPCA) is proposed to obtain structured residual and enhance the isolation ability of dynamic process monitoring, and a compound statistic is introduced to resolve the problem resulting from independent variables in every variable subset. Simulations on continuous stirred tank reactor (CSTR) show the effectiveness of the proposed method.

To reduce greenhouse gas emissions from fossil fuel fired power plants,a range of new combustion technologies are being developed or refined,including oxy-fuel combustion,co-firing biomass with coal and fluidized bed combustion.Flame characteristics under such combustion conditions are expected to be different from those in normal air fired combustion processes.Quantified flame characteristics such as temperature distribution,oscillation frequency,and ignition volume play an important part in the optimized design and operation of the environmentally friendly power generation systems.However,it is challenging to obtain such flame characteristics particularly through a three-dimensional and non-intrusive means.Various tomography methods have been proposed to visualize and characterize flames,including passive optical tomography,laser based tomography,and electrical tomography.This paper identifies the challenges in flame tomography and reviews existing techniques for the quantitative characterization of flames.Future trends in flame tomography for industrial applications are discussed.

A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FTIR. Thermal and mechanical properties were characterized by using com-prehensive thermal analyzer (DSC-TG) and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.

A new 18-lump kinetic model for naphtha catalytic reforming reactions is discussed. By developing this model as a user module, a whole industrial continuous catalytic reforming process is simulated on Aspen plus platform. The technique utilizes the strong databases, complete sets of modules, and flexible simulation tools of the Aspen plus system and retains the characteristics of the proposed kinetic model. The calculated results are in fair agreement with the actual operating data. Based on the model of the whole reforming process, the process is optimized and the optimization results are tested in the actual industrial unit for about two months. The test shows that the process profit increases about 1000yuan•h－1 averagely, which is close to the calculated result.