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After the primary exploration of the preparation procedure of phenolic foam, we studied the modification of phenolic foam by graphene oxide. According to our researches we found that the influence of modifier to the percentage of close area was very little, but it can greatly decrease the thermal conductivity of phenolic foam. In this way, phenolic foam thermal conductivity can be reduced to 0.025 W/m.K.

The p-aminobenzensulfonate-phenol-formaldehyde (APF) condensate is synthesized and characterized by FTIR and TGA analyses. Its properties as drilling mud fluid loss reducer are studied with respect to fluid loss and particle size distribution. In addition, the effect of salt on properties of APF condensate was discussed. Test results show that the APF condensate not only possesses higher thermal stability than sulfomethylated phenolic resin (SMP), a commercial drilling mud additive, but also achieves good property of fluid loss control by reducing the permeability of filter cake; the fluid-loss controlling properties of APF condensate dropped with the increase of concentrations of NaCl.

nanosilica porous thermal insulating composites belong to super thermal insulations, which are prepared by dry molding technology. They have many advantages in comparison with aerogel such as easy preparation and good mechanical property. However, springback phenomenon is found in the process of molding. The springback is easy to lead to cracking of the samples, which directly affects applications of the composites. In order to solve this problem, steam curing method is introduced and the effects of steam curing medium and steam curing time on springback ratio are investigated. The results show that the springback ratio of composites is only 6.45% when water is selected as steam curing medium and the optimum steam curing time is 30 min.

The adaptive fuzzy logic systems are constructed in this paper by utilizing the data information sampled from the inputs and outputs of unknown functions in the nonlinear systems controlled, and then output stable controller is synthesized for a class of uncertain nonlinear systems based on the universal approximation property of adaptive fuzzy logic systems. Finally, the simulation shows the validity of the method in this paper.

Analyzed of GPSR routing algorithms in networks, and applied it to path selection algorithm of traffic guidance system. Then improved it combined with the road congestion information, introduce congestion distance factor, saving travel time.

Using self-designed 30cm×30cm gas explosion experiment pipe and data acquisition system, we found Fe-Ni foam metal suppresses better gas explosion. We analyzed mechanism of suppressing gas explosion from material characteristics,. The three-dimensional holing-through structure of foam metal can quench exploding flame and decline exploding shock wave. Foam metal material has dual advantages of material and structure which can suppress transmission of fire and shock wave. Effect on different parameters of Fe-Ni foam metal materials was contrasted from declining overpressure and flame temperature, and suitable Fe-Ni form metal was optimized for engineering application.

In recent years, recovering zinc from low grade oxidized zinc ore has been a matter of discussion. In this paper, the investigation for recovering zinc and iron from gossan ores was carried out. In generally, the conventional physical separation methods, such as flotation, gravity separation and magnetic separation, were used to treat the low grade ore, and flotation is the most commonly used method for beneficiation and pretreatment of oxidized zinc minerals. However, gravity separation and magnetic separation are used to deal with the gossan ores because of the special zinc oxide ore bearing iron 40.2% in this study. The effects of grinding fineness and magnetic intensity were investigated, respectively. The results show that the grade of zinc and iron increase slightly, and the best result is that the grade of zinc and iron are 13.35% and 40.25%, the recovery of zinc and iron are 53.45% and 52.19%.

In Hubei Province in China, About 15%-40% yield of Burley tobacco losses caused by mildew during air-curing period for High humidity and low temperature. In this paper, active solar utility system was first applied to condition temperature and humidity in the air-curing process. Forced convection solar collectors, natural convection solar collectors and air circulates system were applied in the solar Burley barns. The results showed that: The cost of the system was about 1226 ¥ per drying barn, but it could quickly increase the temperature and reduce the relative humidity of the barn, and the quality and yield were raised. The collector efficiency was about 18.8-24.9%. The average temperature of barn could be improved to 3-4 °Ceven in rainy days. The quality of upper and middle tobacco was enhanced by 11% to 13%; Yields increased by 18% to 23%; The income per acre added 371-392¥; the average income of tobacco increased from 10.49 to 10.87 ¥ per kilograms .

In this paper, a series of novel halogen compounds, melamine halogen acid salts were directly synthesized by melamine and halogen acid in water phase. The chemical structures of melamine halogen acid salts were characterized by Fourier-transform infrared spectroscopy (FT-IR), elemental analysis and1H-NMR. Meanwhile, the thermal properties of compounds were investigated by thermogravimetric analysis (TGA). The TGA results showed that melamine halogen acid salts had good thermostability during polymer processing. Futhermore, limiting oxygen index (LOI) and vertical burning test were used to study the flame retardant properties of composites blended by melamine halogen acid salts and polymer. The results revealed good flame retardancy that flame retardant polyethylene with 2 wt% melamine hydrobromide in total 8 wt% flame retardants got LOI value of 29.7% and reached UL 94 V-0 rating.

This article proposed a way to reduce the error in the measurement of object morphology that based on the phase measurement profilometry with Optical Fiber Projection Grating. Some simulation of the actual light intensity distribution need to do first to get the error that caused by the aperiodic fringes, express the errors by phase. After that, compensate for this error based on the actual measurement results. There is a larger improvement in the accuracy of the recovery after the process proposed in this article than before through the simulation. The experiment verifies the correctness of this method through the measurement of given standard parts.

Three main fractures exist in coal rock mass, including face cleats, butt cleats, and major fractures. The distribution of cleats and beddings in coal rock mass likes a regular reticular. A geological model was established without considering the major fractures. Young's moduli of fractured coal rock mass were gained through a homogenization method monolayer composite micromechanics analysis method. The relations between volume fraction or Young's moduli of cleat and Young's moduli of coal rock mass were investigated by calculation. Results shown that Youngs moduli of coal rock mass have the same change trends with the increase of volume fraction of cleat in the interval of 0.0018mm of width of cleat. And the width of cleat of 0.5mm is a critical point. Youngs moduli of coal rock mass monotonically increase with the increase of Youngs modulus of cleat in the interval of 0.0010.008GPa. Volume fraction and Young's moduli of cleats have notable effects on Young's moduli of coal rock mass.

Introduced intelligent agents to agile supply chain, designed multi-agent coordination mechanism for agents, then proposed agile supply chain based on multi-agent system. This mechanism is applied to a specific enterprise. Multi-Agent strengthens the agile supply chain system reliability, flexibility and scalability, and improves the competitiveness of enterprises.

Vitamin A is an essential nutrient element in animal and human growth, which is usually produced by partially acetylating and transforming retinyl diol. The lipase-catalyzed mono-acetylation can obtain pure monoacetate compared with the classical chemistry process. In the current work, the synthesis of vitamin A precursor of Candida antarctica lipase B catalyzed by regioselective monoacetylation of primary hydroxyl of diol in n-hexane was studied. The reaction rate could be described in terms of the Michaelis-Menten equation with a Ping-Pong Bi-Bi mechanism and competitive inhibition by both substrates. A kinetic model was developed, and the apparent kinetic parameters were calculated as: Vmax =8.45 mmol/ (L•h); K m, vinyl =0.997 mmol/L; K m, diol =161.28 mmol/L; K i, diol =287.32 mmol/L; K i, monoacetate=18.13 mmol/L; and K I, diol =427.40 mmol/L. The current study indicates a competitive enzyme inhibition of highly concentrated diol during lipase-catalyzed acetylation reaction. When the diol concentration in the medium was low, there was a good conformity between the experimental and simulated values with 4.73% average relative error.

The complex situations during a fire disaster, such as high temperature, toxic gas and thick smoke, require helitack crew possess good professional skills. As an efficient and economic training system, virtual reality technology not only provide virtual scene to make crew members get familiar with working environment, but also provides professional skill training to achieve the desired objectives, such as increasing their training frequency, reducing training time, promoting training effects and so on. According to the requirements of helicopter special operation, a prototype is proposed in this paper, and a virtual training system based on some kind of helicopter was developed to validate the prototype’s function, framework design and its capability for further development.

Based on the aircraft cabin customization requirement, the paper compares and analyzes the civil aircraft cabin customization systems of Boeing and Airbus and proposes a frame design scheme of customization systems. Furthermore, it particularly discusses the selection process and results management, and realizes the cabin customization demonstration by virtual reality.

This article has introduced a new electric eddy current retarder by reducing radial size and increasing axial size of the eddy current retarder to meet working condition tailpipe emission monitoring.

Because the coal mine derrick technology needs, to be in from the original winch system of backward 10m based on a new set of new ground winch system, resulting in the original derrick structure stress state change. By using SAP2000 finite element software, the establishment of three-dimensional finite element model, the dynamic characteristics and technological transformation and bar stress were analyzed, for the coal mine derrick technological transformation to provide certain reference.

This paper puts forward a designing scheme of remote monitoring system for parameters of water quality based on GPRS, which is mainly try to improve the existing problems in traditional method such as low monitor frequency, more error in sampling, much dispersion in data. After carefully study the communication principle of GPRS, the monitoring information platform is constructed by adopting chip S3C2440A as key of hardware circuit ,making use of sensor to sample data in real-time, and with public GPRS as data channel. The test turns out that the system works well in function of wireless data channel and data analysis, moreover, it has good property in expansibility for other wireless T&C system.

The technical and economic analysis of supercritical water oxidation (SCWO) and biochemical process for Lurgi coal gasification wastewater (LCGW) treatment were carried out. The findings include the analysis of flow sheet, effluent quality and operation cost of the two processes. Studies show that the SCWO process is more simply and easier to control than the biochemical process. The effluent treated with SCWO process could reach national discharge standard I (GB 8978-1996) without other pretreatment and advanced processes, and could gain 2.3 yuan RMB/t(LCGW). While the operation cost of biochemical treatment is 41.8 yuan YMB/t(LCGW). The SCWO process shows a unique advantage in both technology and economy and will be a promising technique for LCGW treatment.

Smart meters are developed gradually from the traditional power meters, which is an important terminal in the smart grid. It is the foundation of information integration, analysis, optimization and information expression, and undertakes the task to data acquisition, measurement and transmission. This paper reviews the development and application of smart meters, analysis the technical requirements, function of smart meter, and summarizes the benefit of smart meters’ application. It can be concluded that the large-scale use of smart meters will fully reflected energy conservation, efficiency, and safety of the smart grid.

When single phase-to-ground fault happened in power network with arc suppression coil grounded, capacitor current through fault point is compensated and reduced by installing arc suppression coil. Zero-sequence current’s amplitude and phase of fault lines and sound lines are so similar that it increases the difficulty of selecting the fault line. But the resistance component of zero sequence current has no relationship with the arc extinguishing coil compensation, absolute value of resistance component to the fault lines show the maximum, and zero sequence current’s polarity of fault lines is contrary to sound lines. In this paper, because of the characteristic of resistance component, a method is put forward based on zero sequence energy to the line selection in distribution network, it import auto-reclosing techniques into the line selection. The principle is verified by MATLAB simulator. It has high accuracy to select the fault line with this method.

In this paper, WC-12Co coating are prepared by two HVOF systems. The biggest difference between these two systems is the fuel gas use. Morphology and mechanical properties of the coatings are analyzed. The results show that the coating sprayed with Airplane Kerosene fuel gas is denser and the WC particles distribute more even than that sprayed with propane fuel gas. And the WC particles melt more fully. The hardness, Young’s Modules and fracture toughness of the coating sprayed with Airplane Kerosene fuel gas is higher than that sprayed with propane fuel gas.

The paper introduces a new atomization mechanism combining the centrifugal, the oscillating and the impact breakage atomization as a trinity, breaking through the traditional single atomization model. The atomization mechanism here makes full use of the comprehensive effects of the centrifugal atomization, the oscillating atomization and the impact breakage atomization, synthesizing the superiorities of the three as an organic and powerfully efficient whole, and making their mutual reactions stronger step by step. The impact breakage atomization is a new auxiliary mechanism among the three, which can improve the atomizing process of droplets considerably after the centrifugal and the oscillating atomization, producing much better an atomizing result. It is very convenient, simple and direct to fulfill the three-in-one. This atomization mechanism can achieve the goal of even atomization and much tinier droplets and be energy-efficient with low cost as well. Therefore it is a highly practical and useful method.

Tribology behavior of Nanodiamond(ND) polyurethane(PU)/epoxy(EP) interpenetrating polymer networks hybrid materials were tested by friction wear testing machine. Results showed that when EP content was 30%, resultant PU/EP IPNs exhibited best wear resistance. For ND-PU/EP IPNs hybrids, when the ND addition was 0.2wt%, the best wear resistant ability was obtained. Under dry condition, the effect of wear parameters, such as rotational speed, load and central distance to friction and abrasion value were also investigated.

In electricity production and supply system of China, thermal power continues to dominate a larger proportion. In recent years, be influenced by energy-saving emission reduction and low carbon development policy, the environmental impact issue of thermal power project aroused great attention. This study has established a comprehensive evaluation system by analyzing integrated comprehensive effects of the environment caused by thermal power project. Combining with AHP theory, entropy theory and TOPSIS evaluation ideas, the study created a set of scientific assessment model. The research has verified that the validity of the model through empirical studies. And it provided a good theoretical basis for environmental management comprehensive thermal power project.

In recent years, wind energy develops rapidly in China and its comprehensive management research deepens continuously. This paper studies the wind energy level and summarizes the current development situation of our country. The study puts forward a forecasting analysis using Grey Forecasting Theory, and proposes several suggestions for the comprehensive development. The result has reference for improving the management level of the wind power.

This work investigated the thermal stability of nano-silica thermal insulating composites, which consisted of fumed silica, fibers and opacifiers. The volume shrinkage was introduced as an evaluation index to characterize thermal stability of the composites at different temperatures. The effects of serving temperature, serving time, particle size of fumed silica and mass ratio of SiC were discussed. The results indicated nano-silica thermal insulating composites have excellent thermal stability under the temperature of 800°C. The volume shrinkage was correlated positively with serving time. High specific surface area of fumed silica could bring good thermal insulating performance, but at the same time caused high volume shrinkage when applied at high temperatures. SiC as an opacifier has little influence on volume shrinkage, but too much amount may yet increase solid heat transfer and lead to the drop of thermal insulating properties.

In this paper, the conventional physical separation method such as flotation, gravity separation, magnetic separation, alkaline leaching and sulfuric acid leaching were studied. The effects of grinding fineness, amount of agent, magnetic intensity, roasting temperature, roasting time, the leaching agent and leaching time on the leaching of zinc were investigated, respectively. The results show that the leaching rate of zinc is below 50% in the conventional alkaline leaching, and the leaching rate of zinc is below 85% and the leaching rate of iron is above 35% in sulfuric acid leaching. Compared with XRD pattern of the raw ore, the different diffraction peaks of smithsonite is off in alkaline leaching products. In sulfuric acid leaching, the different diffraction peaks of smithsonite are off in the leaching products when sulfuric acid concentration is less than 60 g/L. After 60 g/L, the different diffraction peaks of smithsonite and siderite are off in the leaching products.

Environment is the starting point and the supporting point of the positioning and planning for the tourism development. By analyzing the advantages of the environmental resources of the Xingzhou Entrance Area to the Bijia Mountain in Jinggang Mountain Scenic Area, this paper determines the positioning and strategies for the tourism development of its “Red Land of Peach Blossoms”, and by combining with the setting of the function blocks and starting with the analysis of environmental factors, it carries out the planning and design by taking the reproduction of scenes as its means.

TiB2-WC-TiC-Ni composite tool materials were fabricated using Ni as sintering additive by vacuum hot-pressing technique. The microstructure and mechanical properties of the composite were investigated. The composite was analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). The microstructure of TiB2-WC-30wt.%TiC-Ni composite containing fine WC grains, TiC grains and uniform TiB2grains. A lot of pores and coarse grains were found in TiB2-WC-10wt.%TiC-Ni composite. The pores, brittle phases and the coarse grains were harmful to the improvement of the mechanical properties of the composite. The good wettability and the adequate liquid not only inhibited the formation of the pores and the coarse grains, but also strengthened the interface energy among the grains. The flexural strength, fracture toughness and Vickers hardness of TiB2-WC-30wt.%TiC-Ni composite were 996.6±113.6MPa, 7.64±0.28MPa•m1/2and 23.58±0.82GPa, respectively.

3-dof wire-driven parallel mechanism is studied in this research. The kinematic analysis of this wire-driven parallel mechanism is given according to analytical method. The method for spline function is proposed to generate a continuous, smooth and noiseless trajectory of the wire. The simulation results, based on simulink, verify the rationality of this trajectory planning algorithm

Push-pull pickling line of a branch of WISCO frequently comes up the faults that rotary shear axial locking is unreliable and the cutting precision is low. To solve this problem, two kinds of sickle-like curve have been analyzed, the graphic method and the finite element method were used. The research come to the conclusion that frequent appearance sickle-like curve would produce additional axial impact load on rotary shear's shear blade and also calculated value of axial static load. These are the main reason why the faults appear. After took the proposed solutions accordingly to improve the locking force, the down time were greatly reduced and the cutting precision were improved significantly.

In order to meet the demand for high power linear ultrasonic motors (LUSMs) for many applications, the concept, asynchronous parallel connection (APC) of LUSMs, has been proposed. The basic principle is that multiple stators (vibrators) alternately drive a slider (rotor) in a vibration cycle, the actual driving frequency then increases by the order of the quantity of stators, and better output performance can be obtained. Analysis shows, in the APC, increasing the contact frequency between stator and slider can enhance the output force, speed of LUSM, while at the same time, the mutual interference of different stators in synchronous parallel connection (SPC) can be avoided. Experimental results of double-driving-tips LUSMs demonstrate that, in APC, over 30% more loading force is obtained than in SPC, and over 25% more is obtained than the sum of loading forces from single LUSM driven respectively. In APC, the no-load linear velocity of LUSM is increased more than 10% from that of individual LUSM driving.

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control of induction motor. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, The induction motor speed sensorless direct torque control system can obtain high-precision speed identification. Computer simulations and experimental results show that the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

According to the characteristics of shearer working environment and cutting work, on the base of analyze the working principle of shearer working, use the expert system theory to achieve cutting path planning. Used rule-based knowledge representation, adopted PROLOG language to compile the path planning network, knowledge acquisition used the design method based on rule skeleton and rule body and generated shearer cutting path planning knowledge base, through modifying the internal predicates can be easily achieved the knowledge base modify, storage and maintenance. Experimented in the model of MG900/2210 electrical haulage shearer 1:6 prototype, the experimental results showed that the cutting path planning can effectively improve the working reliability of shearer, by combining with human-machine interaction and remote path correction to solve the problem which can’t be solved through memory cutting and drum automatic adjustment height.

Fine polymetallic sulphides in Dachang mining areas are very difficult to be recovered. In order to solve this problem, a new flowsheet of jet centrifugal concentrator separation-flotation-tabling separation was adopted in this study, which means that jet centrifugal concentrator was firstly used to preconcentrate fine cassiterite, then flotation was introduced to remove sulfides in crude concentrate, and finally cassiterite concentrate was obtained after the flotation tailings were treated with tables. The results of closed-circuit experiment were achieved as concentration grade 44.50% and recovery 52.17% when the feeding grade was 0.30%. The results indicated the new flowsheet can fully take advantage of their characteristics and the fine cassiterite can be effectively recovered.

To construct a finite element model of concrete-filled steel tube column which is suitable to practical engineering analysis, a double-beam (DB) element is proposed. The element is made up of two coinciding beams which simulate steel tube and kernel concrete respectively. The parameters analysis results show that a concrete-filled steel tube column should be divided into four or more DB elements to make the error of fundmental frequency less than 5%. Moreover, based on design codes of the concrete structures and steel-concrete mixed structure of tall buildings, a simplified constitutive model of kernel concrete is developed to consider the confinement effects of steel tube on the concrete. The results of numerical example show that the P-△ curve based on the simplified model is consistent with the experimental results, but the ultimate bearing capacity is less than experimental results. Therefore, the model has a reasonable reliability and can be a reference for similar engineering design analysis.

This paper aims to discuss design methods to reproduce traditional architectures through typology research by engineering teaching group of Yunnan University and points out that the so-called reproduction of traditional architectural form is to present its type and the architectural form created in the design must be a new form based on the corresponding realistic conditions.

Taking the spatial pattern and the environmental elements as the starting point for the study of the ecological design of high-rise office buildings, this paper brings forward the concept of Eco-space Complex, structuring an open and dynamic spatial function complex as well as an eco-conditioning system..

In this paper, a failure analysis is made to a welded aluminum alloy component of the equipment by module below the high-speed train. Making force analysis to the welded components by finite element, microscopic morphology observation and element distribution measurement of the fracture surface are done by the scanning electron microscopy and spectroscopy .It is determined that the main reason of fracture of welded components was that stress concentration exist in the working conditions, and the weld toe is the most severe stress concentration region. The stress concentration causes the fatigue microcrack, and under the action of repeated external force crack propagates and then crack. Lacking of penetration sites is under tensile residual stress, the crack propagation speed, and soon to instability and then broken.

Nanostructured WC-17Co coating was prepared by means of High Velocity Oxygen Flame (HVOF) technique. Characteristic of nano-structure of the coating was analyzed. The coating seems to be of lamination structure formed by fully or partially melted powder. It shows that the coating consists of melted and recrystallized zone, semi-molten zone and un-melted zone. Amorphous phase and nanocrystalline phase co-existed in the coating is due to the rapid heating and cooling during spraying. The nanostructured coating possesses excellent mechanical properties, which are closely related to the unique nanostructures existed in the coating.

For the high speed train, safety is the most important factor. Flash welding is the primary technology for the seamless line rail in Chinese railway. So the quality of the flash welded joints is the most important. This paper presents the situation of joint fracture in rail flash welding joints and analyses the failure mechanism through macroscopic and microscopic observation. The result demonstrate that the cracking of the rail is fatigue-crack propagation，the fatigue cracking is caused by alumina calcium-Aluminates-non-metallic inclusion．

This work investigated the effects of fumed titanium oxide on thermal stability of nano-silica thermal insulating composites prepared by dry process. The results showed that the composites could keep excellent thermal stability at the temperatures below 800°C. However, when the samples were used at higher temperatures (>800°C), the volume shrinkage increased sharply, which directly led to a serious deformation and then affected thermal insulating properties in applications. The utilization of fumed titanium oxide could significantly improve thermal stability of the composites. When 10wt% fumed titanium oxide was added, the service temperature can increase from 800°C to 900°C. The desirable results would be achieved by adjusting the amount of additives according to practical using temperature. In addition, field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD) were employed to characterize the microstructure and phase transformations of the composites treated at different temperatures.

It is fracture, wear and abscission of bit tooth that make up of the main failure forms for the air hammer bit, which have badly restricted the further popularization and application of the air hammer drilling. The main reason is that the ordinary cemented carbide tooth is difficult to meet the complex conditions of the air the hammer drilling. Therefore, this research puts forward a new thought that we strengthen the carbide tooth by adding the nano-Al2O3into the substrate materials of WC-Co. According to the study of several formulas of nano-composites, the test of sample performance, experimental study of impact abrasive wear and microstructure, we draw some conclusions that adding amount of nano-Al2O3can refine grain, make microstructure more uniform and improve the wear resistance of composites, but also can enhance the strength of boundaries of WC-Co and transform the fracture form from the intergranular fracture to the transgranular fracture. Meanwhile, it can also improve nano-composites comprehensive performance by adding rare earth. The result for site test of bit shows that comparing with the bit equipped the original carbide teeth, the efficiency of rock breaking of the bit equipped nano-composites teeth increase by 20% and the service life increase by 80%.

Flotation is a conventional way for treating low grade metal oxide ore which has some advantages such as high efficiency and low cost. In order to recover the zinc from a low grade complex zinc oxide ore in which the grade of Zn is 13 wt.%, this paper presents a preliminary investigation of this type of ore by flotation method. In the experiments, the effects of different parameters such as grinding fineness, amount of Na2SiO3, amount of Na2S and amount of octadecylamine were investigated in relation to the metal contents of concentrates. The results show that about 35% of initial Zn content was obtained with 70% -200 mesh grinding fineness, 1000g/t Na2SiO3, 2000g/t Na2S and 500g/t octadecylamine. It is clear that the preliminary flotation tests with the ore sample indicated that there was no selectivity in terms of zinc recovery. Almost 65% zinc remained in the tailings and could not be recovered by flotation due to its complicated mineralogical structure. Therefore, application of metallurgical processes is proposed for zinc recovery from the tailings in the following investigations.

In this paper, bentonite was applied in mango preservation, and the effects of various treatments methods on fresh-cut mango were studied.The results indicated that mangoes without any treatment easily rotted. The quality indexes of mango such as the weight loss rate, the disease rate and the turning yellow rate tend to increase while the titratable acidity and vitamin C content of mango lose largely. However, the weight loss rate, the disease rate and the turning yellow rate of mango may be reduced when mango were packed in seal bags together with bentonite. Purified bentonite is better than raw bentonite when applied in keeping mango fresh. Burying mango in mass purified bentonite was advisable for mango preservation.

Zinc ferrite is usually formed during the roasting of zinc sulfide concentrate with high content of iron and reduces zinc recovery during the leaching of zinc calcine. Because it is difficult to find pure zinc ferrite in nature ore resources or in chemicals market, which impedes the investigation of the reaction characteristics of zinc ferrite and the seek of new technologies for zinc ferrite dissolution, so it is of significance to obtain relatively pure zinc ferrite for further research on zinc calcine leaching. This article investigated the preparation process of zinc ferrite based on the dissolution characteristics of a zinc calcine with 19.38% iron and put forward a method to judge the reaction end point during the leaching of zinc calcine to produce zinc ferrite. The results show that the product of zinc ferrite could be prepared through recovering the leaching residue during leaching the zinc calcine under the initial H2SO4 concentration equal to or larger than 160g/L, and that the leaching end point can be judged by comparing the experimental curve of Zn leaching with the zinc theoretical dissolvability curve.

This paper introduces performances and characteristics of concrete bar-type plank, a new type of building materials, through detailed graphics recording its applications in State Key Laboratory for Green Building Materials. Also, it proposes issues in further research and potential direction for concrete bar-type plank development widespread used in actual projects, i.e., to become an exterior wall structure system rather than a simple decorative component.

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, the control system can obtain high-precision speed identification. Simulation results show the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

Integrating and querying data from heterogeneous sources is a hot research topic in database research field. The emergence of the Semantic Web brings new paradigm shift of computing in data integration research where data is heterogeneous and distributed. To solve the problem this paper proposes a semantic-based approach. A Semantic-based Heterogeneous Relational Data Integration System, called SHRDIS, is presented. In this system, ontology is used as the mediated schema for the representation of the data source semantics. SPARQL queries over global schema are rewritten into local SQL queries that can be executed on heterogeneous relational databases. The architecture and implementation of SHRDIS is illustrated in detail. The experiment results show that the SHRDIS system has nice performance and scalability.