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A KCl-doped CaO solid alkali catalyst was obtained in a wet impregnation method and treated under microwave irradiation to obtain enhanced stability and activity. Then the catalyst was successfully used in the transesterification of refined waste cooking oil with methanol to produce biodiesel. A uniform design experimentation U7 (74) and regression analysis by DPS software were used to obtain the optimum conditions of transesterification at the lowest cost. Temperature 338K, catalyst amount 4.5% (wt./wt.oil) and methanol/oil molar ratio 9:1, after 90 min reaction, the fatty acid methyl esters yield reached 91.28% and the purity was over 99%, which was up to the national standard for B-100 biodiesel.

In this paper, the self-curable unsaturated polyester was put forward as a new solution to air pollution problems caused by the cross-linking monomer’s volatilization in unsaturated polyesters (UP) industry. Two kinds of unsaturated polyesters with the vinyl double bonds at the side chain were synthesized with Itaconic acid (IA) or Itaconic anhydride (ITA) as raw materials. The first one was prepared with IA, isophthalic acid and propylene glycol (IPP-UP), and the second one was synthesized with glycidol (GL) and ITA (IG-UP). Investigation demonstrates that the latter UP resin could be self-cured through the nucleophilic addition reaction of hydroxyl groups with double bonds or the free-radical homopolymerization of double bonds when they were heated without cross-linking monomers. However, the former couldn’t. Factors on self-crosslinking activity and crosslinking mechamism of pendant vinyl bonds from IA or ITA were explored.1H-NMR and FT-IR were used to characterize.

Due to the increasing consumption of energy, the improvement of the cooling system efficiency has become very important. We use programmable system-on-chip (PSoC) to fabricate a temperature control system. These chips include a CPU and mixed-signal arrays of configurable integrated analog and digital peripherals. This system controls the cooling fan speed by temperature detecting. This system uses buzzer and liquid crystal display (LCD) to remind the users. The user can start emergency protection means at once. However, we have designed a controller to control fan speed in according with the difference of measured temperature. This research has the function of power saving and elements protection by reducing to turn on and off a cooling fan. With a simple modification, we can turn any control fan by PSoC control. Today, everybody must use electric appliance. We will use PSoC with temperature-controlled method together to control the cooling device.

This paper deals with maximum-likelihood (ML) detection of symbol sequence in the absence of synchronization information. A novel iterative scheme is proposed to obtain the ML estimates of the symbols without an estimation of synchronization parameters. Instead of the optimal sampling point recovery and explicit carrier phase compensation, the detection of symbols employs the direct calculation of the matched filter output, eliminating the need for a separate synchronizer. The detection problem is treated as ML estimation from incomplete data, which is solved by means of an iterative scheme based on the expectation-maximization algorithm. The proposed scheme is compared with conventional non-data-aided and iterative ML synchronizers. Accordingly, the simulation results indicate that the proposed detector enables improvements on both the bit error rate and convergence property.

California’s experience on establishing a carbon emissions trading system has been of some reference for Shanghai, China. This paper analyzes some insufficiencies of carbon emissions allowance allocation system in Shanghai, and tries to put forward some suggestions for Shanghai based on California’s experience.

This paper analyzed characteristics of different energy consumption quotas development method focusing on building of green campus as our sustainable development demand and pointed out the development of energy consumption quotas by colleges and universities based on building area per student per stage by use of regression analysis, gaved out the corresponding ratings ,and proposed that correction coefficient should be developed based on properties, scientific research ability and scientific research funds of colleges and universities.

The semi-solid microstructure evolution of hypereutectic Al-20Si-3Fe-1Mn-4Cu-1Mg alloy was studied by unidirectional compression deformation experiment, at a range of deformation temperature of 833K~873K and a range of strain rate of 0.1s-1~0.001s-1. The results showed that the microstructure of the reheating alloy was more spherical and fine than the microstructure of as-cast, the alloy was a positive strain rate sensitive material that the flow stress was decreased with increasing in deformation temperature and it was increased with increasing in strain rate. The mechanical properties of the alloy were hardly improved when the deformation temperature was too high to fracture the thick phase of the alloy.The lower strain rate was not only reducing the productivity but also reducing the plastic deformation. The microstructure of the alloy which the thick phase was broken fundamentally and the grain became further refinement can be obtained at 833K~853K, and at 0.1s-1~0.01s-1.It can be done that reducing the plastic deformation resistance and strengthening the fabrication procedure of the alloy.

Fine rolled twisted bars as the vertical prestressed reinforcement has been widely used in the prestressed concrete box girder, but it is hard to effectively control the loss of prestressed force in the practical engineering. Too much loss of prestressed force will lead to diagonal cracks in box girder webs. According to the dynamic theory, take the exposed segment of fine rolled twisted bars as the beam model, take the anchorage segment as a rigid arm and two elastic supports, this article establishes the plane elastic support model of vertical prestressed fine rolled twisted bar. The nonlinear relationship between vertical prestressed tensile force P and the plane stiffness of elastic supports K is established by an indoor experiment, and at the same time the anchoring section stiffness coefficient method is used to verify the effectiveness of this method and conduct an engineering application. This paper provides a theoretical basis for the test of vertical prestressed tensile force in box girder.

The non-linear finite element program Ls-DYNA/ANSYS is applied to simulate numerically the capacity for the geo-materials to dissipate the energy induced by the falling objects. The calculation results for the crushed stone coincide well with those recommended by the current Code of《DNV-rp-f107_2010》, which is on the basis of experiment data, implying the feasibility of using this program to estimate the energy dissipating capacity of the geo-materials. Because little research has been performed with clay soil, the program Ls-DYNA/ANSYS is used to predict the energy dissipating capacity of clay layers.

Due to its good formability characteristics, such as high strength, high initial work hardening rate, as well as continuous yielding, thin-walled DP steel possesses great advantages of weight loss and security, and has been used to replace ordinary steel for automotive parts manufacturing by a lot of automotive industry. But along with the improvement of the performance of the strength, the high strength steels formability is worsened dramatically, and failure and fracture often occurs in its cold stamping process. So, hot stamping technology must be adopted to make the formability available. In the paper, it took the hot stamping process of DP steel engine hood for example and took DP800 as object of research. The forming limit, variation of major strain, minor strain and thickness, as well as the potential equality defects were analyzed by using eta/DYNAFORM software. The research results show that duplex steel plate can meet the performance requirements of car engine dumping plank forming, which offers theory basis for the production of similar parts.

In order to study the remedation technology of eutrophic artificial lake, an integrated restoration technique consisted of aquatic vegetation near lakesides, Effective Microorganisms (EM) , fingerlings and intermittent aeration system was constructed in Guilin City, Guangxi of China. The results indicated that the removal rates of Chemical Oxygen Demand (COD),total nitrogen (TN),total phosphorus (TP),suspended substance (SS) and turbidity achieved by this kind of technique were 63.14%~77.10%,54.18%~60.54%,85.76%~87.98%,82.36%,79.28% respectively, and the coverage ratio of duckweed decreases from 90% to 10%. Compared with conventional wastewater treatment systems, the integrated restoration technique do not cause secondary pollution, and has an obvious effect, especially it can maintain good water quality for a long time.

The use of Principal Component (PC) algorithm is explored for the efficient representation observations from high-resolution infrared sounders for the purposes of data assimilation into numerical weather prediction (NWP) models. A new version of the fast radiative transfer model has been developed that exploits principal component analysis and then implemented into the WRF 4D-Var data assimilation system, thus allow the investigation of the direct assimilation of PC scores from Atmospheric Infrared Sounder (AIRS). Testing of a prototype system where 119 AIRS spectra replaced by only 20 PC scores show significant computational saving with no detectable loss of skill in the resulting analyses or forecasts. The methodologies implemented in this regard are examined and the potential for future increased use of the data are explored.

In view of building a green campus is needed to the sustainable development of our country, this paper based on the energy consumption statistics and energy audit work of campus in Hubei province, and basically got the energy consumption status in Hubei province, the energy consumption indicators are between 28.3kgce / (student • a) and 269.6 kgce / (student • a), the average level is 95.0kgce / (student • a). The main factors affecting the energy consumption of campus were analyzed, including colleges of arts, science, engineering nature, the school's research capacity, and research funding and other factors. What’s more, we come to the conclusion that the relatively scientific evaluation indicators of the campus energy are indicators of annual energy consumption per student, the equivalent value correlations of which reach 0.81.

In most of the AC-DC hybrid power transmission system AC filters is widely applied to stabilize voltage level in addition to filter harmonic. However, the voltage stability of AC bus is greatly influenced by action sequence of switching AC filters in group. The paper presents the concept of reactive characteristics of the convertor and AC filters, using reactive and voltage control mode to switch them. The modeling, control, and principle of operation for the AC-side switching filters are described. The voltage level is controlled via regulating action of switching filters by step. The salient feature of the proposed control modes is that voltage control contributes to keep the voltage level, and reactive control has no fast response on guaranteeing voltage stability, but two methods can apply to different occasions based on the requirements of voltage stability. All analysis and control system designs are verified through building a RTDS model in a typical ±500kV power system.

In order to improve the scientificity and accuracy of ground source heat pump energy efficiency testing, the paper discusses the principles and methods of energy efficiency testing, the requirements of the testing instruments' selection and installation and the arrangement of measuring points.The paper shows how to diagnosis instruments and process system failure according to the concrete situation on site,and points out the methods of systematic troubleshooting and fault elimination.

Flotation column was originated from foreign countries, firstly it was mainly used in coal classification, then it has been used in nonferrous metal classification, due to the hematite iron ore resources tend to be poor, fine and complex, flotation column has the congenital advantage of micro fine minerals, therefore, this paper is according to the beneficiation technology of fine hematite ore in domestic and foreign ,through the characteristic of flotation column which is applicable to the processing of fine mineral, have good separation effect, and high enrichment ratio , flotation column are introduced in fine particle hematite beneficiation in some applications, Flotation column has a wide range of application prospects in our country fine mineral separation.

A vertical U-tube ground heat exchanger can be utilized to exchange heat with the soil in ground source heat pump systems. The outlet temperature of the working fluid through the U-tube not only accounts for heat transfer capacity of a ground heat exchanger, but also greatly affects the operational efficiency of heat pump units, which is an important characteristic parameter of heat transfer process. It is quantified by defining a thermal effectiveness coefficient. The performance evaluation is performed with a three dimensional numerical model using a finite volume technique. A dynamic simulation was conducted to analyze the thermal effectiveness as a function of soil thermal properties, backfill material properties, separation distance between the two tube legs, borehole depth and flow velocity of the working fluid. The influence of important characteristic parameters on the heat transfer performance of vertical U-tube ground heat exchangers is investigated, which may provide the references for the design of ground source heat pump systems in practice.

In order to improve plastic property of AZ31 alloy tubes at room temperature and expand application of cold rolling process in magnesium (Mg) alloys, solution treatment (T4) and cryogenic treatment of AZ31 tubes obtained by drawing were investigated in this work. The results indicate that T4 can improve the microstructure of the alloy, refine grains and eliminate twins. The optimized T4 parameter is 300 °C for 8 h, in which the average grain size of 12 μm can be obtained and elongation reaches to Max of 16.1% and tensile strength reaches to 242 MPa. Moreover, tensile strength was decreased to 211 MPa, while, elongation was improved to 25.4% by T4+cryogenic treatment at-196 °C.

The composite was produced by pouring melt Al into solid Cu pipe. Microstructure, mechanical properties and Cu-Al composition distribution in Cu/Al composite interface were studied in the paper. The experimental results show that Cu and Al diffuse to each other, which the Cu/Al interface zone is formed. Moreover, there are lots of Cu-Al phase appearing in the Cu/Al interface zone. Furthermore, the influences of annealing temperature on the peal strength of Cu/Al interface were tested, in which the peel strength of the Cu/Al interface zone reaches the highest point to 15 MPa at 350°C and then decreases with the annealing temperature increases. In addition, the width of the diffusing layer and the average grain size of the Cu/Al interface zone increase with the annealing temperature increases.

Self curable unsaturated polyesters with pendant hydroxyl groups on main chain were synthesized through the polycondensation of maleic anhydride and glycidol at different raw material ratios. The preparation process and self-curing properties were studied. Investigation demonstrated that the unsaturated polyester resin could be self cured through the addition reaction of pendant hydroxyl groups with the double bonds on main chain when it was heated above 150°C without additional cross-linking monomer. This research may contribute to improve air pollution caused by volatile of cross-linking monomers. H-nuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize.

We demonstrate experimentally the enhanced performance of the plasmonic silicon solar cell by using a nano-sized indium-particles and different thickness of TiO2 space layer structure. The optical reflectance, dark and photo current-voltage, and external quantum efficiency are measured and compared at each stages of processing. The conversion efficiencies enhancing of 17.78%, 27.5% and of 47.85% are obtained as the solar cell with indium nanoparticles on a 10-nm, a 30-nm and a 59.5-nm thick TiO2 space layer, respectively, compared to the solar cell without coated a TiO2 layer. Furthermore, the plasmonics conversion efficiency depend on the thickness of space layer are also demonstrated that the increasing by 15.46%, 12.1% and 6.08% for the solar cells with a 10-nm, 30-nm and 59.5-nm thick TiO2 space layer, respectively, were obtained.

Aim at gob in loess gully region is the only ways of West—East oil and gas pipeline, the risk assessment on oil and gas pipeline through gob is solve operation of pipelines, and prevent the occurrence of major disasters and urgently need to study and solve major problems. It combines with integral method to further risk assessment on oil and gas pipelines across god based on the results mining subsidence hazard study in loess gully region. The method has proved that has some guidance on risk assessment of oil and gas pipelines through the loess gully region, and it is for further study on overlying gob pipeline movement and deformation to lay the theoretical basis.

A theoretical analyzing approach about the compound floor isolation system consisting of RFPS and dish spring is derived. Computation results show that for the proper specifications, the floor isolation system may exhibit good effectiveness in mitigating the acceleration of the unfixed objects or equipments in both horizontal and vertical direction, while the extra displacement could be limited to be in a manageable range. The expected parameters for mitigating the accelerations agree with that for displacements in a partial domain. The specification of a floor isolation system needs low friction coefficient on the slide 0.05

Cement concrete pavement as a common form of the road has been widely used because of its high strength, stiffness, and good durability characteristics. In order to explore failure modes and the strength control factors of the cement concrete pavement in the region, site investigation and the orthogonal test method in laboratory are used. Test combination design for the main control factors of the cement concrete strength was executed based on orthogonal test method. Strength of concrete specimen was determined by using indoor pressure test machine. The results show that the chiefly control parameter of affecting concrete strength is water cement ratio and the following are sand ratio and the coarse aggregate grading.

Vehicle emissions from mobile sources are major contributors to air pollution and varied with vehicle types, vehicle styles, traveled miles, temperature, oil types and the methods of operation and management. This study performs three emission factor models, Mobile-Taiwan 2, Mobile6.2 and EFDB to calculate emission factor of mobile sources from year 1986 to 2011. The emissions of primary air pollutants, MIRs and CO2emitted from mobile sources were calculated. The contribution ratios of varied vehicle types for different air pollutants would be compared and analyzed. Estimated emissions from mobile sources were 32.2, 177, 643, 197 and 401 kilotons/y for PM10, NOx, CO, THC and MIR for 2000; 31.3, 115, 305, 114 and 227 kilotons/y for 2011. Emissions of traditional air pollutants presented a decreasing trend because of fourth-stage emission standards for mobiles sources and CO2 revealed an increasing trend. According to presented control technology for greenhouse gases on mobile sources, ratio of emission for year 2011 to 2000 would be 1.38-1.49.

Oil whip phenomenon is the common fault in rotor-bearing system. The reason why oil whip happens often has been researched in high-speed rotor-bearing system. But in practice engineering, due to the requirement of work condition, oil whip cannot be avoided all the time in rotor-bearing system. The paper is based on the relation criterion of oil whip happens in rotor-bearing system, the reliability mode and system reliability of oil whip are defined, and the reliability analysis method for avoiding oil whip in rotor-bearing system is carried out. The effect on reliability sensitivity of random parameters is studied. Numerical results are also presented and discussed.

A study on deformation of multipoint flexible clamped thin-wall components during numerical control drilling in vertical direction downward is presented. The finite element model of multipoint flexible clamped thin-wall component during machining is established with program ANSYS, and a static analysis of deformation of the model is conducted. The laws of maximum deformation under different skin thickness, under different cutting force and on the 3 special machining paths in the cut area are obtained. The results show that the maximum deformation is linear with cutting force and exponential with skin thickness, and the function curves of the maximum deformation on the 3 special machining paths are all different, the function curve 2 is the composite superposition of the function curve 1 and the function curve 3.

This paper progresses to dynamically simulate and study the heat transfer process of horizontal ground heat exchangers in the multi-grooves by the use of numerical simulation based on the layout and heat extraction or rejection conditions of horizontal ground heat exchangers under the artificial lake. Effect of buried pipe type and groove spacing on the heat exchanger process is analyzed in detail. The influence of annual average water temperature change on the surrounding environment is evaluated with the introduction of parameters including summer weekly average maximum temperature rise and winter weekly average maximum temperature drop, in which can take the technical supports for the design of horizontal ground source heat pump system.

According to the application conditions of horizontal ground heat exchanger(HGHE) under artificial lake, this paper uses numerical simulation method to do dynamic simulation research of the heat transfer performance of HGHE, analyzes the effect of connection mode and pipe flow velocity on heat transfer performance of HGHE in detail，puts forward efficient HGHE loop formation mode，and will provide effective technical support for ground-source heat pump system design with HGHE.

Surface subsidence has some peculiarities for the mining of the Han jia wan coal mine. Based on the surface movement observation of 2304 working face in Han jia wan coal mine, mining strata movement parameters are analyzed, the main factors which influence the formation of surface cracks in the gob are proposed and the failure mechanism of surface movement and deformation are studied for the mining of shallow coal seam and thick loose bed. Correlative parameters are presented and scientific basis is established for the coal mining under buildings, rail and water and the leaving of the safety pillar in the future.

By simplifying the triangular tracked engineer vehicle into dynamic model of half-tracked vehicle with five freedom degrees which includes four vertical jumps and one rotation, a corresponding dynamic differential equation is set up to each degree of freedom. A method of road roughness simulation, based on the time series of White Noise, is also represented and then verified. The simulation analysis of the tracked vehicle ride comfort is built on MATLAB/SIMULINK, based on the incentive signal of an imitated road. The simulation results show that the method that White Noise generated road roughness is applicable and prove efficient in the ride comfort research of the triangular tracked engineer vehicle. Thus a theoretical foundation is established for the optimization for ride comfort of the triangular tracked engineer vehicle.

Aiming at the ability to adapt to different road conditions of limited-slip differential(LSD) in drive axle, by building the without preloading friction disk type limited slip differential mechanical model, We derive the theoretical formula of the locking differential coefficient of the theoretical formula of limited slip differential without preload friction disk from mathematical theory derivation, and fitted theoretical curves, Which can be used as reference for further studies on other limited slip differential. Experimental verification was applied to the designed drive axle, experimental results shows that, the actual performance parameters of each drive axle design values consistent with the theory, to prove the correctness of the theoretical derivation, proved the correctness of theoretical analysis.

This study utilized the car chasing method to chase 86 light-duty vehicles on seven major roads in the Shin-Chu area and establish the typical driving patterns for various roads. The 23 parameters that associated with the driving were considered to elucidate the features of driving patterns. This work examined two manners, corrected Euclidean distance and traditional Euclidean distance methods, to elucidate a representative driven cycle. In the screening procedure of the typical driven cycle, factor analysis was applied to correct Euclidean distance and examine the 23 variables of driving conditions. The results indicated that the first five of the 23 principal components explained at least 94% of the variance for seven roads. The physical interpretation based on factor analysis was better than the traditional Euclidean distance method, so the results of factor analysis were used to select the typical driven cycle. The average speeds were 34.1 kmh-1 for the city road; 36.8, 26.1 and 30.4 kmh-1 for county roads 118, 120 and 122; 38.7 and 36.5 kmh-1/ for provincial roads 1 and 3; 85.9 kmh-1 for freeway.

The engineering geological condition of the mine goaf and the exploitation method are proposed with an engineering example. With the study on surface failure mechanism, the structural stability of key layer and the deformation control function of damaged buildings, the simulation model is built. The surface movement is analyzed with FLAC3D. Moreover, the building stability and impacts of mine goaf are evaluated. Finally, the disposal measures of mine goaf and the protection methods of buildings are given. By comparing the simulation results with the practical observation data on surface movement, the condition and method produced are efficient and precise.

This paper focuses on the power gaining in Nantong planning (1895-1926), and the role that an individual could play in local city planning issues. This study analyzes the evolution of Zhang’s power gaining in four periods through reviewing literatures, investigating historical remains, and interviewing the scholars studying on Zhang. The conclusions are as follows: Firstly, Zhang inherited the power in deal local issues as local elite. Secondly, he tried for new powers by borrowing the concept of Local Self-governance from the west. Thirdly, he also could make new powers through business approaches.

Nantong made great progress in city construction during 1895-1926 by the leading of Jian Zhang, upon which Zhang's Urban Planning Thoughts was emerging.Zhang went to Japan for a 70 days' visiting on education, business, political system, and local city construction, thereby obtained much illuminations from it. The research was applied during 2006-2008 by re-visiting the cities, places of Japan that Zhang went to in 1903, and collecting literatures in libraries, museums, historical archives of those cities. This paper considered that the effect on Nantong city construction was distributing in education, industry, agriculture, housing, business, traffic, landscape, and philanthropy. The influence of Zhang's Urban Planning Thoughts was mainly in local self-government, system planning, infrastructure planning, education system planning, and planning methods, etc.

In order to optimize rolling process of AM50 Mg alloy, numerical simulation method is adopted to find reasonable process parameters. And then, the metallograph was viewed to find the microstructure evolution during hot rolling process. Through numerical simulation it is found that while the heating temperature is 420 and the train less than 0.33 each time. Through 10 times rolling, a 10mm thickness plate was rolled to 0.5mm, and its grain size also decreases to 10μm, which indicates that AM50 Mg alloy can be formed by hot rolling method.

In order to improve the dispersion of multi-walled carbon nanotubes (MWCNTs), MWCNTs were physically modified by the surfactant of Poly (vinyl pyrrolidone) (PVP), cetyl trimethylammonium bromide (CTAB) and sodium dodecylbenzene sulfonate (SDBS), and were chemically treated by the acid oxidation. Measuring the zeta potential of the dispersions of modified MWCNTs and surface contact angle of modified MWCNT powders, influence of acting forces on the dispersions of modified MWCNTs was analyzed. The balance of electrostatic repulsion and van der Waals forces determines the stabilization of aqueous modified MWCNT dispersions. The sufficient reactive groups, ions and long molecular chains play important roles for such balance.

Silk fibroin hydrogels is an important morphous of biomaterial. As a natural protein collosol, purified native silk fibroin solution can be gelatinized under certain conditions. The main mechanism of the gelation is that the fibroin molecules turn into the β-sheet conformation from the random coils. This transformation of silk fibroin molecules would be influenced by various parameters such as the temperature, pH value, ion concentration and so on. In this paper, the effect of ultrasonication on the gelation velocity and structure of silk fibroin were discussed. It is believed that the cavitations caused by sonication could accelerate the process of gelation of silk fibroin. Our experiments demonstrated that the ultrasonic treatment could greatly reduce the silk fibroin gelation time, especially at a high sonication power exceeding 400W. The results of XRD, FTIR, and Raman spectra indicated that the ultrasonication had no significant effect on the final structure and composition of the silk fibroin gels except the acceleration for the molecular transition from random coil and α-structure to β-sheet conformation of silk fibroin. The SEM images showed freeze-dried fibroin gels close to the ultrasonication source had compact structure, while the structure was more loosening far away to the source.

Aluminum films were deposited on glass substrate by electron beam heat evaporation, and porous alumina films with high transmittance were prepared by means of anodic oxidation under different anodizing conditions in oxalic acid solution or phosphoric acid solution respectively. Thus the morphology of these porous alumina films was characterized by different structural. he optical transmittance spectrum at normal incidence over the 300~1000nm spectra region were obtained by spectrophotometer, which shows, in visible and ultraviolet light region, the transmittance of porous alumina films prepared in oxalic acid solution is much better than that prepared in phosphoric acid solution. The SEM analysis results showed that the pores are circular and uniform in porous alumina prepared in oxalic acid but irregular and non-uniform in that prepared in phosphoric acid, which affected the surface roughness of alumina films.

For today’s coal mining enterprises, the mining production environment is very harsh and sometimes there are electric leakages in the automatic production equipment which cause a great impact on the stability of coal production. This paper proposes an electric leakage fault intelligent detection model. The intelligent method can fix the electric leakage faults on time which is an important prerequisite to ensure mine production stable and secure. The experimental results show that the model can effectively detect hardware failures and leakage.

Combustion of power fuel in a large thermal power plant produces a great deal of harmful flue gas, which endangers personal safety of residents around it. In this paper, the injury mechanism of flue gas ejected by the thermal power plant is analyzed. The injury indexes of flue gas ejected by the thermal power plant are put forward. In order to improve the safety status of flue gas ejected by the thermal power plant, we developed a special instrument, which can detect on-line the injury indexes of flue gas ingredients, particle species, ejection speed and ejection flux in the ejected flue gas. The detection data can be used to assess the safety statue of the ejected flue gas, to predict the injury degree of the ejected flue gas to people and to provide basic data for establishing the valid emergency schemes.

In order to eliminate thermal deformation of large-scale precise machine tools caused by ambient temperature change, self-alignment design principle and key points are proposed for a large-scale precise machine tools, Self-alignment simulation experiment, machined parts experiment and compared results for self-alignment rail grinder and other similar products are analysed, the present analysis show that self-alignment rail grinder has many advangtages of good precision, straightness stability.

Al8B4C7 should be a successful antioxidant in carbon-containing refractories, and it have excellent hydration resistance. In this paper, the synthesis process of Al8B4C7 and the mechanism have been studied. Aluminum, borax and activated carbon powders were used as starting material. Using borax as the source of B, can greatly reduce the cost of synthesis. Our experiments showed that use these materials can synthesize Al8B4C7, and the final product is closely related to the temperature and ratio of raw materials. Al8B4C7 appeared at about 1300°C, and with the temperature increased, more Al8B4C7 was generated in the heating samples. The phase compositions of these samples heated at 1700°C were Al8B4C7, Al2O3, Al4O4C and Al2OC.

This paper proposes a rapid dynamic analysis method for microgyroscope using system vibration modes to solve the problems concerning to the computing time in the performance analysis of microgyroscope. The results of eigenvalue solution are employed to construct the state space model. The response of the microgyros cope can be reconstructed as a response superposition of the vibration modes, and then the system equation is decoupled into an uncoupled equation. The dynamic response of the microgyroscope can be calculated by a simple superposition.