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The effects of melt flow on dendrite growth during solidification are studied by the quantitative phase field model coupling the Navier-Stokes equations. Through analyzing the relationship between flow velocity and dendrite growth rate in simulations, a flow Péclet number involving with characteristic flow velocity, characteristic length of the zone affected by flow and thermal (solute) diffusion coefficient, is suggested for dendrite growth under convections. The growth rate increment due to flow follows a power-law relationship with the Péclet number. As the Péclet number is much higher than one, the influence of convection on dendrite growth is apparent, whereas as it is below one, the flow effects can be neglected.

Glassy carbon electrodes (GCEs) were modified by TiO2 and Ag/TiO2 heterostructured nanobelts, respectively. The corresponding electrodes were marked as TiO2/GCE and Ag/TiO2/GCE, respectively. The electrochemical properties of Ag/TiO2/GCE had good and stable electrochemical characteristics in phosphate buffer solution (PBS), and it can be applied to the trace detection of L-cysteine. When the concentration of L-cysteine is in 10-7 order of magnitude, it is more sensitive.

A Triac dimmable LED driver based on SSL2101T is designed. The driver based on flyback topology with an extra Triac dimmer and a 220V/50Hz mains input achieves flicker free, smooth dimming. The proposed driver has acceptable efficiency and power factor. The Triac dimmer and the driver are introduced and the dimming control theorem is analyzed. The design of the transformer is demonstrated in detail. Experimental results show that the full load efficiency of a demo board is 73%, power factor 0.762 and the dimming range from 0 to 347.7mA.

Discussed the structure feature, working principle, communication protocol and design of hardware and software of the intelligent measurement and control device based on CAN bus in this paper.

Harmony search (HS) algorithm is a good meta-heuristic intelligent optimization method, which has been paid much attention recently. However, intelligent optimization methods are easily trapped into local optima, HS is no exception. In order to improve the performance of HS, a new variant of harmony search algorithm with random mutation strategy (HSRM) is proposed in this paper. The HSRM uses a random mutation strategy to replace the pitch adjusting operation, and dynamically adjust the key parameter pitch adjusting rate (PAR). Experiment results demonstrated that the proposed method is superior to the HS and recently developed variants (IHS, and GHS) and other meta-heuristic algorithm.

Diamond is a kind of ultra-hard and difficult-to-machine material. By means of the graphitization of diamond, dynamic friction polishing (DFP) technology is used to achieve a high-efficiency material removal of diamond. The polishing plate of DFP plays a key role in the process of polishing, and catalytic metal with unpaired d electrons is considered as ideal polishing material. To discuss and verify the feasibility that amorphous alloy can be used to polish CVD diamond film by DFP, Fe based amorphous alloy was prepared by mechanical alloying method and spark plasma sintering technology. The results showed that diamond film got a higher removal and a better polishing effect. This work provided a new selection for the polishing plate used for DFP of diamond.

This paper discusses the evaluation of the level of pesticide safety and designs and realizes the software of pesticide safety evaluation on B/S. The function of the software includes inquiry of pesticide safety, inquiry of evaluation index information and management of users’ information etc. It owns practical values.

Hybrid electric vehicles has the potential to save energy consumption and relieve exhaust gas emission while the power flow control techniques are very important for improving a hybrid electric vehicle’s performance. In this paper, the system simulation and control method of series hybrid electric vehicles were proposed. The control method was based on enhancing the energy transfer efficiency based on dynamic programming algorithm. The hardware in the loop (HIL) simulation was constructed containing a real-time driver and controller in the simulation platform, which can be used to evaluate the proposed strategy.

In this paper, TiO2/diatomite and Ce-TiO2/diatomite were prepared by sol-gel method in order to improve the spectrum responding range and its photocatalytic effect. The obtained samples were characterized by means of X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM), Infrared Absorption Spectroscopy (FT-IR) and so on, and the photocatalytic activity was evaluated by methylene blue degradation. The heat stability of TiO2/diatomite was improved by Ce-doped; TiO2 was successfully loaded on diatomite through physical and chemical action. The de-coloring ratio of methylene blue of the two composite materials were similar under UV light, Ce-TiO2/diatomite was higher under visible light, it reached to 80%, and it kept 65% after the five times repeated using of Ce-TiO2/diatomite.

In order to accurately extract various types of industrial solid wastes from high resolution RS images, a industrial solid wastes feature fast extraction algorithm was proposed based on SVM. The reasonable image pretreatment was conducted by anisotropic diffusion filtering firstly. It is because that high resolution RS image contains abundant information and industrial solid wastes heap was very complex, we proposed the classification algorithm based on 1-v-1 which could extract multi-class industrial solid wastes fast and accurately at once. The new algorithm improved both efficiency and accuracy of industrial solid wastes recognition. The experimental results show that the industrial solid wastes feature recognition of SVM has better advantages than conventional methods. The new algorithm can recognize not only shape features of industrial solid wastes heap but also its material and type and it is constructed to recognize multi-class industrial solid wastes with higher operation efficiency.

In order to research the changes of concrete properties in freeze-thaw environment, five concrete samples with water-cement ratio respectively equal to 0.60, 0.65, 0.70, 0.75 and 0.80 were tested in freeze-thaw environment according to GB/T50082-2009 concrete rapid freeze-thaw cycles test method. Five samples were carried out 0, 25, 50, 75, 100 times faster freeze-thaw cycles test. With the increasing number of freeze-thaw cycles, the concrete relative dynamic modulus of elasticity loss rises, the compressive strength drops, and the carbonation depth increases. The greater the water-cement ratio of concrete specimens with freeze-thaw cycles, the greater the degree of damage increases.

The paper introduces the correlation technique and implementation method of pesticide information query system which is using the Android cell phone to realize prevention and treatment of tropical crop diseases and insects. It mainly involves techniques such as Android technology, Java technology, Http communication protocol, JDBC database connection and operation, SQL language, etc. Peasant users would convenient and easy to query crop pest prevention and control method with cell phone, and get pesticide scientific knowledge in crops, to guide the use of pesticides safely

There are three work posts in this warm extruder: upsetting station backward extrusion station and blanking station. They work continuously. The manipulator is mainly used to passing artifacts from one station to another. The warm extrusion forming process manipulator for steel connecting sleeve typically was designed to reduce labor intensity and enhance production automation level. The machines structure and working principle were described. In the same time, the machine control system that adopts the PLC programmable controller can simplify the control system, and its reliability strengthens further. Practices show that the strapping machine has the advantages of simple structure, high efficiency, low cost and small vibrating noise.

The strapping machine for Paper Bills typically was designed to reduce labor intensity and enhance production automation level. The machines structure and working principle were described. There are three work posts in this equipment, they work continuously. This approach makes it very easy to split up a complex transformation into a series of simple transformations arranged in a loop line. The machine includes currency count/counterfeit distinguishing system, conveying system and strapping system. In the same time, the machine control system that adopts the PLC programmable controller can simplify the control system, and its reliability strengthens further. Practices show that the strapping machine has the advantages of simple structure, high efficiency, low cost and small vibrating noise.

Granite, due to the poor adhesiveness with asphalt, cannot be widely used as aggregate in asphalt pavement. In this study, nanoscaled calcium carbonate (CaCO3), was selected as modifier to modify asphalt. The adhesion of aggregate and asphalt was evaluated by Boiling test method and the Marshall Test and Immersion Marshall Test were conducted on asphalt concrete (AC-16) according to the Standard Test Methods of Bitumen and Bituminous Mixture for Highway Engineering (JTG E20-2011). The results showed that When the Doping content of CaCO3 (%) is 7%, the adhesion levels reached up to 5 grade and achieved the project requirements. The Immersion Marshall Stability (MS1) of AC-16 CaCO3 modified asphalt concrete can improve 27.6% than that the Matrix asphalt concrete.

In this paper, we prepared a series of powders (pure TiO2 and Ce-doped TiO2) by sol-gel method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), infrared spectrometer (IR) and UV spectrophotometer. The results indicated that the doped Ce influence the crystal structure of TiO2 and improve the temperature of crystal transformation. In the degradation of MB experiment, after 5 hours, the degradation efficiency of them (pure TiO2 , Ce-doped TiO2 and P25) under UV light is about 99.1%, while under visible light,Ce-doped TiO2 is about 60% higher than pure TiO2 and P25, up to 73%. This illustrates that the doped Ce increase the absorption to visible light and improve the photocatalytic efficiency.Key Words: TiO2, Ce-doped TiO2, photocatalyst, sol-gel method, crystal form

With about equal amount of austenite and ferrite in volume fraction, duplex stainless steel (DSS) is in advantage of mechanical properties and corrosive behaviors. Hence it is widely applied to the heavy castings for nuclear power plants inshore, such as impellers, pumps and valves. However, lots of cracks usually occur in these castings during manufacturing processes, because it is susceptible to precipitate the brittle intermetallic compound of sigma phase when the castings are exposed from 600 to 1000oC. In this work, the precipitation of sigma phase was observed by optical microscope (OM) and scanning electron microscope (SEM) in a cast DSS named as MAS/6001, which aged at 850oC from 5 to 300 minutes. The effect of sigma phase on the mechanical properties was analyzed by the tensile at room temperature and impact tests at -10°C. The results show that sigma phase in the MAS/6001 steel precipitated simultaneously with the secondary austenite, which obeyed the eutectoid reaction. The interfaces between austenite or secondary austenite and sigma phase were the locations where cracks generated from the void aggregation. Cracks are susceptible to propagate along or cross these interfaces, and to promote the sigma phase breaking-off, which severely deteriorated the mechanical properties.

Bulk glasses of xNb2O5(1-x)La2O3(NL) with high refractive index were prepared by aerodynamic levitation method. Only when x ranges from 0.62 to 0.72, NL glasses can be obtained. The effect of compositions on the thermal property and refractive index was investigated. The results indicated that the glass transition temperature ranged from 733 to 767 with the increasing of La2O3in NL glasses, while the crystallization peak ranged from 811 to 837 . The glasses had high refractive index ranging from 2.26 to 2.31. According to the Drude-Voigt relationship, the Abbe number of the glasses was calculated to be about 20. This type of glass was colorless and transparent in the region from visible to infrared region. Thus, the niobate glass system has promising application in lenses, next-generation optical disk, and endoscopes.

The sensitization and intergranular corrosion (IGC) behavior of a novel Cr-Mn-N austenitic stainless steel (named as MPMD133) sensitized in the temperature range from 600 oC to 1000oC for 3 hours was investigated by the double loop electrochemical potentiokinetic reactivation (DL-EPR) test. The effects of the sensitization temperature on the susceptibility to IGC of MPMD133 were examined in the 0.5M H2SO4 +0.01M KSCN electrolyte solution. The results show that the degree of IGC increases as the sensitization temperature increasing till 900oC. Meanwhile it decreases rapidly when the sensitization temperature is elevated up to 1000oC, which is confirmed by the subsequent optical micrographs observation. The XRD analysis reveals that the precipitation of Cr23C6 leads to chromium depletion along the grain boundaries, consequently results in the susceptibility to IGC.

An analytical method was developed for determining free and oligosaccharide-bound sialic acids in bovine colostrum by HPLC. The condition of acid hydrolysis for sample and sialic acids derivatization were investigated. The sialic acids were released from their parent oligosaccharides by acid hydrolysis using 40mL 0.1mol/L sulphuric acid for 100min. They were then derivatized using O-phenylenediamine (OPD) at 70°C for 40 min, the determination of the derivative could be carried out by UV detection. The total content of free and oligosaccharide bound sialic acids in bovine colostrum milk were 941.95μg/mL. The developed method is validated on various dairy products such as bovine milk and milk-based products.

The adsorption of acetamiprid and phenol in water onto the resin of ZHP02 modified with proline based on NDA150 was investigated from the static experiment at different temperatures in single component system and binary components system. The adsorption capacities and adsorption selectivity for acetamiprid and phenol in waste water were tested. The results showed that the adsorption was fitted by Freundlich model, and the adsorption of acetamiprid or phenol on ZHP02 was an exothermic process. The cooperative adsorption existed in binary components system when the equilibrium concentration was higher. The adsorption of acetamiprid onto ZHP02 had little change in the presence of phenol, but the adsorption of phenol onto ZHP02 was weakened significantly in the presence of acetamiprid. The electrostatic force between acetamiprid and adsorbent was stronger than phenols, so acetamiprid was adsorbed preferentially onto ZHP02.

There are periodic changes of meshing teeth in electromechanical integrated toroidal drive, that lead to time-varying meshing stiffness. By converting time-varying stiffness into the form of Fourier series, dynamics model and the corresponding differential equation of parametric vibration system are established. Then approximate analytical solution of the system is obtained by multi-scale method, and time domain response curves of damping vibration system are given. The analysis results show that free vibration of the system not only include natural frequency, but also contains combination frequencies between natural frequency and meshing frequency. So there are multi-resonance frequency sections. Those will provide more theoretical supports for system dynamic design and optimization.

Compared with the gas-compressed refrigeration system, the diffusion absorption refrigeration cycle has no moving part and the associated noise and vibration. It can be operated without any electric input and driven by various energy sources, has no the problem of the substitute of CFC, furthermore it has positive significance in energy conservation, off peak, environmental protection, and promoting the use of gas. So it has broad application prospects as a kind of absorption refrigeration mode. In the development of diffusion absorption refrigeration technology, the performance of diffusion absorption refrigeration system has been improved and enhanced continuously. The paper presents and discusses the recent research progress of diffusion absorption refrigeration which contains design of bubble pump, adjustment and optimization of operation parameters, utilization of low-grade thermal energy and selection of working medium. The research direction of diffusion absorption refrigeration in the future is suggested.

The objectives of this study were to analysis the differences of microbial community diversity between the microbial additives (MA) compost and natural compost and the distribution (spatial and temporal) of MA during high-temperature composting by PCR-DGGE technology. The results showed that the MA started temperature rapidly; prolonged the time of maintained high-temperature process and increased the diversity of microbial than natural compost. Sequence comparison revealed that the microorganisms most belonged to uncultivable, thermophilic bacteria. Bacillus became the dominant microorganisms after mixed with MA. MA were found in the top and middle portions of the compost throughout nearly the entire composting process,but absent in the natural compost. Our finding represents an important step towards the understanding of MA and its function in the degradation process of compost.

For analysis the performance of cluster tools, Stochastic Petri nets model was used to describe the serial process procedure of cluster tools and the operation sequence of the robot. The firing rate of transition represents the frequency of activities. In order to improve the scalability of the model, the modular approach is used to model. Firstly the sub-models of tool’s modules were developed. Then according to the process procedure, all the sub-models were combined to construct a Petri nets model. Finally, the firing rates are added to every transition. Markov process approach was used to analyze model. Some performance measures equation are deduced, such as the throughput, the utilization of process chamber, the utilization of the robot and the wafer residency rate in process chamber. Petri nets models and performance measures equation developed in paper can assist performance analysis and verify the effectiveness of scheduling algorithm.

The aim of this work was to study the separation conditions of Liquiritin (LQ) in preparative liquid chromatography. Based on the inverse method, the adsorption isotherm parameters of LQ and the closely impurities were determined. Then the chromatographic conditions were optimized by combination of orthogonal design experiments and numerical simulation. The optimum injection concentration, injection purity of LQ and injection volume was found as 50 g/L, 45 % and 5 mL, respectively. The parameters of simulated moving bed chromatography were selected and the separation process was analysis. This method can give reference for purifying of low content component from the complex herbs.

High throughput is critical to the success of semiconductor manufacturing. The complexity of cluster tools leads to higher throughput an increasingly challenging task. To compute the throughput of the cluster tool and simulate the system operation procedure, the simulation platform, named as ClusterSim, is developed. Moreover, the paper analyzes the performance of the parallel cluster tools by this platform and valid the simulation results using the theoretic model. The result shows that ClusterSim provides an effective tool for users to quickly evaluate many possible equipment configurations

This study aimed to optimize the culture conditions (agitation speed, aeration rate and stirrer number) of hyaluronic acid production by Streptococcus zooepidemicus. Two optimization algorithms were used for comparison: response surface methodology (RSM) and genetic programming coupling Quantum-behaved particle swarm optimization algorithm (GP-QPSO). In GP -QPSO approach, GP is employed to model the microbial HA production and QPSO algorithm is used to find out the optimal culture conditions with the established GP estimator as the objective function. The maximum predicted value of HA production by RSM and GP-QPSO was 5.27 and 5.57 g/l, respectively. Here though both RSM and GP-QPSO approach provided good predictions, yet the proposed GP-QPSO method showed a clear superiority over RSM for both data fitting and optimization capabilities

To make nano calcium carbonate as the modifier, firstly the best proportion of nano calcium carbonate is determined as 6% by comparing the influences of different proportions of nano calcium carbonate to the indexes of asphalt. Then the influence of mixing with nano calcium carbonate to the performance of asphalt concrete AC-13 has been studied. Tests show that, the mixing of 6% nano calcium carbonate has improved the dynamic stability of asphalt concrete AC-13 from 991 times/mm to 1269 times/mm; the residual stability from 0.87 to 0.94. This indicates that after mixing with nano calcium carbonate, both the high temperature performance and water stability of asphalt concrete have been improved.

Product competition is depended on the each process success of product designing which contains complicated designing. A good many scholars promotes some design method. But each method applies to one problem in a certain phase of product innovation designing, and contains insufficiency. Therefore the only solution is to integrate all the variety of methods. HOQ (House OF Quality) is a good method which establishes the relationship between user and designer. But it can’t solve conflict between technology parameters. TRIZ ((Russian Abbreviation:Teorijz Rezhenija Izobretatel skich Zadach is very powerful method to solve the contradictions and obtains innovation. And TRIZ can only gives principle solutions. The paper integrates to use the above methods to design successfully force sensor of testing apparatus for micro-friction. Test shows its dependability and precision of designing project is very high. So reliability and feasibility of integrated technology of HOQ/TRIZ is very strong.

To understand the dendrite formation during solidification phase-field model has become a powerful numerical method of simulating crystal growth in recent years. Two phase-field models due to Wheeler et al. and Karma et al., respectively, have been employed for modeling the dendrite growth worldwidely. The comparison of the two models was performed. Then using the adaptive finite element method, both models were solved to simulate a free dendrite growing from highly undercooled melts of nickel at various undercoolings. The simulated results showed that the discrepancy between the two phase-field models is negligible. Careful comparison of the phase-filed simulations with LKT(BCT) theory and experimental data were carried out, which demonstrated that the phase-field models are able to quantitatively simulate the dendrite growth of nickel at low undercoolings, however, at undercoolings above ten percent of the melting point (around 180K), the simulated velocities by Wheeler and Karma model as well as the analytical predictions overestimated the reported experiment results.

In order to improve the quality of college mathematic education, cultivating rational thinking of people, and improving the quality of nation, this paper make a comprehensive and systematic survey and analysis on college mathematic education. Results show that the team-constructer and quality of students in university have been changed, and it is not optimistic for mathematic learning of students. For the above problems, it is important and necessary to adjust the teaching content, improving teaching methods and means, promoting the cultural ideas and history of mathematics, and show humanistic concern to students.

For the operation situation of the series-type electrostatic fabric filter precipitator, the deflectors in the inlet of the precipitator whose angle and spacing were changed to improve the air distribution characteristic and collection efficiency were assembled. The three-dimensional structural model of the series-type electrostatic fabric filter precipitator was built and meshed, then carried on the number simulation of air distribution characteristic with FLUENT. The simulation results show that when the deflector spacing is 0.7m and the incremental height is 0.15m the air distribution is more uniform. The numerical simulation result is reasonable and can be used as the reference to optimize the designing of electrostatic fabric filter precipitator.

Like bacteria, fungi play an important role in the composting process as major decomposers of organic substances. As only a small fraction of the fungi present in composting can be cultured because conventional microbiological techniques limited information on the composition of fungal communities in composting. Molecular methods are expected to give a more realistic view of species richness and distribution. For this purpose, we selected universal PCR primer set that allow the specific amplification of fungal 18S-ribosomal-DNA (rDNA) sequences. DNA was extracted from composting samples, and 18S rDNA genes were amplified by EF4/Fung5 (0.6kb) and EF4/NS2-GC (0.4kb). DGGE analysis of the fungal community in the composting of a microcosm experiment was carried out after amplification of total DNA with both primer pairs. Clear banding patterns were obtained with amplified production. 13 different bands excised from the DGGE gel were sequenced and compared with genbank. Sequencing showed that some could not be cultured; some were efficient cellulose-degrading strains. The results showed that diversity and composition of the fungal community in the composting can be analyzed by the combination of 18S rDNA PCR amplification and DGGE.

Special reason and common reason bring on the process disturbance. Statistical process control (SPC) is commonly used to monitor the process disturbance which arises from assignable reason. Engineering process control (EPC) compensates the deviation of output for common reason based on the feedback adjustment principle. Therefore, integrated SPC/EPC approach has better performance than that merely using SPC or EPC. However, in practice, it is very hard to search the appropriate method to apply for integration of SPC/EPC. The main reason is that EPC’s compensation has depressed probability which assignable reason is monitored by control chart. In this paper, a joint-monitoring method is designed to account for the above problems through detecting process output as well as monitoring process input. An example is given to prove that joint-monitoring can detect the process disturbance more quickly and more accurately.

Former studies and application of vermifiltration process to organic wastewater treatment has given an affirmative effect for the pollutant removal in wastewater. It could be used for the disperse wastewater treatment, especially for rural living sewage. We developed a new multilayer vermifiltration system in this study, expecting to enhance this ability for the disposal of rural living sewage. The result showed that all the COD, BOD5 and SS values in outflow after vermifiltration could meet GB18918-2002. The removal rates of COD，BOD5 and SS were above 75%, 85% and 90% respectively. The N and P could be partly removed. These preliminary results give a positive prospective for the application of multilayer vermifiltration in rural sewage treatment in the future.

Metallothionein (MT) is one kind of proteins induced in organism under the stress of heavy metal. It plays a great pole in detoxification and tolerance of heavy metal. In this study, according to the rich conservative sequence in MT, we designed corresponding primer, then cloned MT mRNA gene induced by As in earthworm E. andrei and got its nucleotide sequence. The results proved the presence of MT in Eisenia andrei, and showed that roxarsone could induce the expression of arsenic MT gene.

Gene encoding β-glucosidase was amplified through PCR by using the genome DNA extracted from L .delbrueckii subsp. delbrueckii as a template. The gene encoding β-glucosidase was inserted into a prokaryotic expression vector pET-28a(+) and expressed in E.coli strain BL21(DE3). The gene encoding β-glucosidase was of 1380bp. The nucleotide sequence of the gene encoding β-glucosidase from L. delbrueckii subsp. delbrueckii showed as high as 97.9% homology comparing with that from L. delbrueckii subsp. bulgaricus indicating that the gene encoding β-glucosidase is highly conservative. The enzyme activity was about 34U/mg and the molecular weight of β-glucosidase is about 51 kDa analyzed by SDS-polyacrylamide gel electrophoresis.

One kind of multi-void three-dimensional microstructure models based on homogenization method is constructed. Based on multi-void microstructure, the mathematical models for the topological structural optimization which takes maximizing the total potential energy as the objective function is constructed, then the Kuhn-Tucker optimality condition of the update method about the designs variable based on the porous microstructure can be gotten when optimization iterates. Finally, in explaining the employed algorithm an example is provided.

The research of crack-tip field in damage materials is a very complex problem. The core question is how to give the damage constitutive equation and determine the crack tip singularity order of magnitude of the physical quantities. Taking into account the damage process is a process which the energy (strain) accumulates, and the initial damage threshold value existence, on the Lemaitre’s research foundation, the brittle material damage constitutive equation that has the initial damage quantity and the power order relationship with strain is given. Under the assumption that stress (strain) is finite, the construction of III mode crack tip damage fields is studied and the solution of crack-tip stress (strain) asymptotic field is given. Finally, the relationship of the initial crack tip damage zone and full damage zone Scale and material parameters are discusses. These works provide theoretical basis for the material engineering design and the appraisal structure reliability.

At present the study on the application of the topology optimum design in scraper conveyor is still under development. In this paper the topology optimization based on the homogenization method is applied to the design of the baffle on the scraper conveyer, which can provide a valuable conceptual design scheme for the selection of the baffle pattern. In conjunction with the homogenization theory and Finite Element Method (FEA), the mathematical models for designing the baffle by the minimizing mean compliance are developed in this paper. By applying the topology optimum design to the baffle, the topology optimization based on the homogenization method is proved to be reliable and practical at the conceptual design stage of baffle.

With the use of energy, the pollution is more and more serious. As the largest pollution family, coal-fired power plant must control the pollution strictly. It established model of a coal-fired power plant SCR system, and simulated the denitration under different boiler load conditions, to get the denitration efficiencies and the regular of the denitration efficiency under different boiler load conditions. It can provide recommendations for practicality run in coal-fired power plant SCR system.

Powder of Ti-46at%Al alloy was synthesized through mechanical activation (MA) and then sintered and concurrently consolidated in a short sintering time of 900 s by using spark plasma sintering (SPS) process. The XRD and SEM profiles show that the microstructures of TiAl alloys contained γ TiAl and small amount α-2 Ti3Al phase, whose amount can be controlled by the sintering temperature. The compacts retained the original fine-grained fully densified bodies by avoiding an excessively high sintering temperature. The alloys sintered at higher temperature with this process showed a coarser microstructure. So it is possible to produce dense nanostructured TiAl alloys by mechanically activated spark plasma sintering (MASPS) within a very short period of time.

At present the study on the application of the topology optimum design in scraper conveyor is still under development. In this paper the topology optimization based on the Solid Isotropic Material Penalization (SIMP) is applied to the design of the middle pan, which can provide a valuable conceptual design scheme for the selection of the middle pan pattern. In conjunction with the homogenization theory and Finite Element Method (FEA), the mathematical models for designing the middle pan by maximizing the rigidity are developed in this paper. By applying the topology optimum design to the middle pan, the topology optimization based on the SIMP method is proved to be reliable and practical at the conceptual design stage of middle pan.

A genetic diversity analysis was conducted, of 14 wild Auricularia auricula strains and 6 cultivated strains from DaXing'anling region by SRAP and ITS markers. Using PCR-SRAP system, we selected 9 pairs of primers for the wild and cultivated strains respectively, and analyzed their genetic diversity through clustering analysis. The results were as follows: 88 fragments were amplified, and the polymorphic bands were 76. The PIC (polymorphism information content) value of these markers varied from 0.048 to 0.918, averaging 0.599. Kinship of Auricularia auricula strains was determined by analyzing their ITS sequences. The software ClustalX 1.83 and MEGA 4.1 were used to conduct the phylogeny analysis. The results were as follows: ITS 1, 5.8 S, ITS2 had as many genetic loci as 52.1%. Cluster analysis of the two kinds of markers were congruous and there were more genetic diversities in wild strains than in cultivated strains. SRAP and ITS techniques can be used to analyze the genetic diversity in the future study.

Developing easy cleaning and antibacterial ceramics is the key to actualize the ceramics with functionalized, high-quality and band established in china. This paper which combined with research status from home and broad analysed the performance influence of ceramic glaze with different processing methods and discussed the way and methods which can improve the quality of ceramics.

Numerical simulation is used to study the combustion process，temperature distridution and NOx emission for a 10t/h chain boiler with and without flue gas recycle. And at the same time,it is constrasted that differences when flue gas is recycled to the primary wind inlet and to secondry wind inlet.The results show the temperature distridution decreased with flue gas recycle,so there is less NOx emission.And when flue gas is recycled to secondry wind inlet ,the NOx emission dropped mostly. The result offer a reference to design and operate a chain boiler.

A novel segregative carbide was discovered during the manufacture of high speed steel roll. The carbide with rectangular shape is a type of MC carbide not yet reported in the open literature. It is a face centered cubic carbide with a lattice parameter a=0.414445 nm, very close to the VC carbide but with a different chemical composition. The M represents the metallic elements (at.%): 91.80 V, 3.17 Cr, 2.19 Fe and 2.83 Mo.

Mold filling process in horizontal centrifugal casting was analyzed in this paper. The effects of rotation speed on flow pattern were studied. Results show that the flow pattern changes greatly with increasing rotation speed and the first thread interval shows significant differences within each group. It is found that inappropriate rotation speed results in liquid drop during filling process, leading to casting defects.

Carbides in HSS roll were studied systematically. The results showed that there were two kinds of carbides in HSS roll, 1st and 2nd carbides. 1st eutectic carbides included the chrysanthemum-like MC mainly consisting of V and the plate-like M2C rich in Mo. 2nd carbides were complex carbides, concentrating Fe, Cr, Mo and V elements. The morphology, distribution and alloy concentration of the 1st eutectic carbides were studied using OM, SEM and EDS. During heat treatment, evolution of the 1st eutectic carbides was analyzed. It was found that the MC carbides had no change in morphology, components and distribution, while the M2C carbides decomposed to M6C and MC. In order to improve the properties of HSS, a method of increasing solidification rate was defined to refine the eutectic carbides. After refinement, the eutectic carbides distributed both along the grain boundaries and inside the grains.