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VPCS with [Si-CH2-CH2-Si] structure were synthesized through hydrosilylation reaction of divinyldimethylsilane and diphenylsilane. VPCS were mixed with additive liquid PMPS silicone rubber and VPCS/PMPS based ablative composites were also prepared. VPCS play an important role in improving the thermal stability of PMPS. The 10% weight loss of VPCS/PMPS is 530.6°C, and Tmax is at 601.3°C, 43°C and 48°C higher than PMPS. Anti-ablation fillers have great important on composites. VPCS/PMPS/ZrB2 showed higher mechanical properties and ablative resistance, which is accordance with the results of SEM morphology observation.

A kind of MDT polysiloxane was prepared by step hydrolysis and polycondensation of alkoxysilane. It could be cured at elevated temperature with existence of microencapsulated platinum catalyst. The effects of crosslinkable groups’ contents and PhSiO1.5 content on properties of cured silicone resin were studied in detail. When the contents of crosslinkable groups were 20mol% to 30mol% and the PhSiO1.5 content was 25mol% to 30mol%, the cured silicone resin had good tensile strength, flexural strength, moderate elasticity, and low viscosity. With the increase of PhSiO1.5 content from 17mol% to 32mol%, Tg of the silicone resin could be improved by 50°C to 128°C. The thermal stability was explored by thermo gravimetric analysis. The onset temperature of thermal degradation and the center temperature of thermal degradation were 486°C and 548°C, respectively. The average dielectric constant was about 2.45 and the dielectric loss tangent value was less than 0.01. The silicone resin also showed a high-volume resistivity of 5.6×1016Ω•cm. These results suggest that such silicone resin is suitable for utilization in electronic packaging.

One component room temperature vulcanized (RTV) silicone resin was prepared by combination of a kind of polydimethylsiloxane-b-phenylsilsesquioxane copolymer with crosslinker and catalyst. The effects of feeding order on properties of cured silicone resin were studied in detail. When hydroxyl terminated polydimethylsiloxane was added in three times and the D/T ratio was 2.0~2.3 during synthesis, the cured resin with the hardness over 20Shore D had the better elastic-plastic properties and heat resistance than the other two feeding orders. The tensile strength was over 3MPa and the elongation at break was above 75%. The Td5% was 416.6°C.The silicone resin also had good radiation resistance. At the radiation dose of 1500kGy, there was no obvious defect observed in the material, and the tensile strength increased to 6.83MPa, while elongation at break decreased to 26%.

Thermal conductivities of silicone rubber filled with Al2O3 were prepared. Thermal conductivity experimental results obtained were analyzed using the Nielsen and Agari models to explain the effect of Al2O3 filler on the formation of thermal conductive networks. Thermal conductivities increased with the adding of mixed Al2O3 of large and small sizes fillers. The scanning electron microscopy (SEM) showed that it is the optimum particle sizes and quantities that made the filler packing closer, which thus leads to formation of more thermal conductive chains.

Crosslinker (polyvinylsilicone oil, C gum) and curing agent (2, 5-bis (tert-butyl peroxy)-2, 5-dimethyl hexane, DBPMH) were used to change the crosslink density of the thermal conductivity of silicone rubber filled with Al2O3. The results show that the thermal conductivity of silicone rubber changed with its degree of crosslinking. When the Al2O3 loading was 5 vol. % and a completely continuous conducting network had not formed, the thermal conductivity of the vulcanizates decreased with increasing crosslink density. The thermal conductivity of the vulcanizate with a suitable amount of C gum increased to 53%, and the tensile strength increased by 0.8 MPa compared to the vulcanizate without C gum. When the Al2O3 loading was 30 vol. % and a completely continuous conducting network had formed, the crosslink density of vulcanizates changed as the amount of DBPMH changed. The thermal conductivity of vulcanizates first decreased and then increased with increasing crosslink density. There was a valley value in the thermal conductivity–crosslink density curve.

One component room temperature vulcanized (RTV) silicone resin was prepared by combination of a kind of D-T polysiloxane block copolymer with crosslinker and catalyst. Transparent coating with good elastoplasticity without any inorganic filler could be obtained by exposing the RTV silicone to air at room temperature. The structure of D-T block copolymer played an important role in the properties of the cured products. It was synthesized by polycondensation of partially hydrolyzed phenyltrimethoxysilane (phenylsilsesquioxane, T units) with silanol end-capped polydimethylsiloxane (PDMS, D units). The effects of the viscosity of phenylsilsesquioxane and the D/T ratio on the properties of cured product were investigated. When phenylsilsesquioxane (10000cP at 80°C) was used and the D/T ratio was 2.0~2.3, cured products with tensile strength above 2.5MPa and elongation above 70% were prepared. RTV silicone resin composed of such kind of D-T block copolymer had good heat resistance because the existence of phenyl group and the highly cross-linked 3D structure. The Tonset was 387.6°C and the Tmax was 518°C.

Aiming at the problem of poor high-temperature wear-resistance of rope clamp used in super-high speed elevators, the experiments of laser cladding to prepare carbide reinforced composite coating were made. nanoTiC powder, Ni-based alloy powder were used as cladding material. The microstructure and hardness of composite coating were tested by relevant equipments. The research results show that the composite coating is made up of TiC, Cr3C2, Fe3C and Fe-Ni-Cr-C HYPERLINK "javascript:void (0);" solid solution. When the content of TiC is 10%, 30%, the morphology of TiC is presented as dendrite-like and the morphology of HYPERLINK "javascript:void (0);" solid solution is presented as cellular-like. When the content of TiC is 50%, the morphology of TiC is presented as block-like, lath-like. There are some microcracks on grain boundaries. At the content of 30%, laser power 1.5KW, scanning speed 600mm/min, the laser cladding has no crack and hole. The average hardness of composite coating is 701HV0.2. Using this technology to the surface strengthening of elevator parts, the wear resistance and service life can be greatly improved.

A Fourier series method based on Mindlin theory and Hamilton variation principle has been proposed for the vibration modeling and analysis of composite laminated plates with arbitrary boundary conditions, in which the vibration displacements are sought as the linear combination of a double Fourier cosine series and auxiliary series functions. Three types of constrained springs are introduced to establish a general structural model of composite laminates, and the vibration model is established by combining the Hamilton energy principle. The accuracy, efciency and validity of the two solutions presented are demonstrated via comparison with published results. The influence of boundary conditions, laying angle and laying layer on vibration characteristics is analyzed. And it can be seen that the frequency of the structure increases with the increasing of the spring stiffness and the number of laying layers of the boundary of the laminated plate structure.

The kinetics of the thermal degradation and thermal stability of thermal conductive silicone rubber filled with Al2O3 and ZnO were investigated by thermogravimetric analysis in a flowing nitrogen atmosphere at a heating rate of 10°C/min. The rate parameters were evaluated by the method of Freeman–Carroll. The results show that the thermal degradation of silicone rubber begins at about 350°C and ends at about 600°C. The thermal degradation is multistage, in which zero-order reactions are principal. The kinetics of the thermal degradation of thermal conductive silicone rubber has relevance to its loading of thermal conductive filler. The activation energies are temperature-sensitive and their sensitivity to temperature becomes weak as temperature increases.

Phenyl silicone resin reinforced addition type liquid phenyl silicone rubber was prepared by vulcanization of vinyl end-capped polymethylphenylsiloxane (PVPS), phenyl MT resins and hydrogen end-capped polydiphenylsiloxane (PHPS) under Pt catalysis at 150°C for 4h. The effects of the proportion and the vinyl content of phenyl MT resins on the mechanical properties of cured products were investigated. The thermal stability was explored by thermogravimetric analysis. The changes of mechanical properties were also studied before and after irradiation. Phenyl silicone rubber with good performance was obtained when the phenyl MT resin content was 50~60 wt% and the vinyl content was at 5.5~6.6 wt%. The onset temperature of thermal degradation and the center temperature of thermal degradation were 443.7°C and 502°C, respectively. When the radiation dose increased from 0 to 300 KGy, the tensile strength decreased from 4.1MPa to 2.3MPa and the tearing strength decreased from 8.9MPa to 5.1MPa. When the radiation dose continues to increased from 300 to 900 KGy, the tensile strength increased from 2.3MPa to 6.4MPa and the tearing strength increased from 5.1MPa to 6.5MPa. During the process of radiation, the elongation at break had been kept down from 96% to 52%, and the hardness increased from 80A to 90A.

High-throughput drug screening microfluidic chip has good biocompatibility and faveriable functional integration, which is the excellent platform for high-throughput screening. Importantly, FRET (Fluorescence Resonance Energy Transfer) technology is the most efficient detection means at present. In this paper, we introduce the development of drug screening microfluidic chip on cellular level and the application of FRET technology on cell detection. Further, we discusse the possibility of FRET applied in the field of microfluidic biochip.

Octavinyl polyhedral oligomeric silsesquioxane (POSS) were used to hybrid with polysiloxane matrix by two methods, physical blending (PB) and chemical modification (CM). Mechanical, thermal and morphological properties of composites were studied by changing the percentage of POSS and investigated by thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and wide angle X-ray diffraction (XRD) measurements. The results show that the hybrid composites have better mechanical and thermal property than the parent polymer matrix, and CM-prepared composites show better reinforcing role compared with PB-prepared samples. The CM method was hydrosilylation reaction of octavinyl-POSS with hydrogen terminated poly(methylphenylsiloxane) (HPMPS) and the FTIR and NMR results of modified POSS revealed that hydrosilylation reaction took place successfully but was not complete. The modified POSS consisting partial segments of HPMPS attached to the central POSS core showed better distribution in matrix than PB-prepared POSS hybrid composites.

Deep red emitting CaAl12-xO19:xMn4+ phosphors were synthesized by solid state reaction method. Various fluxes (BaF2, H3BO3, Na2CO3 and NH4Cl) were added in preparation of the phosphors. The influences of the various fluxes on the crystal structure, morphology and luminescent properties of CaAl12O19:Mn4+ phosphors were studied. The results show that the obtained phosphors with fluxes possessed better luminescent intensity than that of the phosphors without fluxes. The maximum luminescent intensities were found with the following order: H3BO3 (2.0 wt%) > Na2CO3 (0.5 wt%) > NH4Cl (0.3 wt%) > BaF2 (0.1 wt%) > no flux. The H3BO3 flux can decrease the single phase forming temperature of CaAl12O19:Mn4+ phosphors by about 150°C.

Automatic cotton picker was widely used in contemporary cotton production operations, moreover, the farmers prefer to small cotton picker, and picking mechanism is the most important parts of cotton picker, therefore, the research on the movement of picking mechanism is very important. This paper introduced a new kind of the opposite-two-rows type automatic cotton picker, analyzed its operating principle, and made a theoretical derivation of the equations of motion of the picking mechanism, the obtained results can provide theoretical guidance for the design of picking mechanism of cotton picker.

In the era of the Internet as the core of globalization the interaction of enterprises, enterprises are faced with a series of thorny issues about how to make social relations resources into corporate sales and development resources. In the past Management strategy is from product-centric to customer-centric. If the companies want to survival and development, we must establish a good relationship with closely customers. By a good corporate credit, high quality products, quality service, to attract new and old customers to standardize the management, warm and caring, and efficient services to support management to maintain the loyalty of the old and new customers. In the Internet environment CRM is an important part of the customer service support management. Online customer service support for management information systems will be enterprise customer-facing portal. A comprehensive customer service support management information system can enhance the competitiveness of enterprises, increase sales, enhance corporate image. Customer service support management is to ensure customer satisfaction and customer interests. How to give full play to the advantage of customer service in the Internet environment to support management information system. And how to enhance customer service in the Internet environment to support the management interface of the customer satisfaction, improve the enterprise's customer retention will become an issue of concern. In the above context, customer service support management information system came into being. The system is provide feedback record inquiries and task allocation to provide customers with more personalized service to help companies achieve customer intelligence decision analysis.

Until now Intelligent network technology has been widely used in the communication network. In recent years, competition in the mobile communication market is more intense, the user of communication network has put forward higher request in smart grid technology’s service and quality. Improving its marketing competition and ensuring intelligent network operate in the right direction have become the urgent desire and demand of the operator. In consideration of the demand of operators, this paper puts forward solutions for Intelligent network which based on mobile intelligent network‘s business evaluation system, and introduces the design and development of the evaluation system of the business in detail.

This paper describes the positioning based on ZigBee network, and it provides location indoor information and node state alarm information. Wireless sensor indoor positioning system consists of 3 types nodes: the coordinator node, reference node and blind. Time synchronization protocol is an efficient synchronization technology star network structure, synchronization to the gateway node as a starting point, each cluster head node synchronization tree network structure. The paper presents novel model of wireless sensor indoor positioning algorithm and time synchronization protocol. Experiments show that the design of indoor positioning system can meet requirement function and performance of nodes positioning system.

Fuel cell operation with a dead-ended systems anode reduces fuel cell system cost, weight, and volume because the anode external humidification and recirculation hardware can be eliminated. However, water accumulation is one of the key factors which influence the stability of its performance. Generally, the anode flooding of PEMFC with anodic dead-end operating mode can be avoided by using periodic purge process. But such an operating method can lower the utilization efficiency of hydrogen because small amount of hydrogen is expelled out of fuel cell and wasted. In order to improve the utilization efficiency of hydrogen, the pulsating technique at anode has been proposed. In this paper, the investigation of the hydrogen pulsation effects for PEMFC stack has been made, with only continuous hydrogen supply, with between continuous hydrogen and pulsation hydrogen at different positions, such as the inlet or outlet of anode. The results shows that the performance of a PEMFC stack has been improved significantly when the pulsation hydrogen flow introduced from the outlet at anode.

Digital information service is an important topic, which is based on the personalized information service, therefore, this paper takes individualized information service and information integration as the starting point to analyze and discuss the reason of information integration. Moreover, it takes the individual requirements of users as the basis according to the user-oriented principle, putting forward the concept of personalized information integration.

This paper make use of C/S (Client/Server) as the major structure and B/S (Browser/Server) as the minor structure to design the community property management system,using SQL Server 2000 database to design the overall framework of system and complete the process of its implementation. The results showed that the system had friendly interface, interactivity, security and confidentiality,which is easy for the community property managers to meet the needs of owners and improve their work efficiently as well.

Deformation measurement is an important content of engineering surveying and the main objects of the deformation measurement are civilians, industrial buildings, precision engineering, large dam, bridge and the earth's crust deformation of rock mass. Deformation measurement aims to obtain the deformation data in the process of displacement deformation, and to get the deformation of the status, trend and possible results through the analysis of these data. The existing automatable solution for measuring the deformation all adopt the 3-dimension displacement test, which based on high precision total station, unattended, automatic data acquisition and transmission control mode.

There are many people at the restaurant. Once a fire breaks out, it will pose a serious threat to life safety. So the safe evacuation design is the focus of the restaurant. BuildingEXODUS can provide high dynamic simulation of evacuation. According to the simulation results, we can study the affect of evacuation safety exit. At the same time the simulated data can be used to deal with fire, earthquake and other emergency evacuation.

Based on typical parts CNC machining technology solutions, using the inverted spindle, high-capacity storage automatic loading and unloading of the workpiece conveyor systems, temperature tracking control system, ladder-shaped bed base and other new technologies. A milling-turning flexible machining cell was researched and developed, which means once the piece was fixed, all the procedures, including turning, milling, drilling, reaming, tapping and other processes integrated processing, can be completed. As an advanced manufacturing mode, it was suitable for the efficient processing of short-sleeve-type parts, panel parts, etc.

In view of the current network structure of the Smart Substations in China, the industrial Ethernet is analyzed with respect to the presence of long latency that may be found in the communication of Smart Substation, the configuration complexity that is not conducive to repair and the maintenance involving relatively high economic costs. A connection-oriented switching network technology is then proposed on similar issues, with a leaky bucket model being built up based on the substation information flow. Subsequently, the service classification and priority scheduling mechanism are placed to introduce the network calculus to calculate the delay bound of each of information flows. Conclusively, based on the IEC62439, a network communication method for Smart substation is established to solve the problems with the Industrial Ethernet application in smart substation.

As one of the quenched and tempered steels, 40Cr steel is often used to manufacture the shaft in heavy-duty trucks. To adjust the working environment of the heavy-duty machines, 40Cr steel should have high impact property. In this study, different tempering cooling mediums were treated as critical influence on improving impact property of the steel. After heated under 520°C tempering temperature, the samples of 40Cr were cooled in air, oil and water, respectively. The experiments were carried out through charpy impact, metallographical and SEM analysis. The results has shown that 40Cr steel of high impact property and fine microstructure can be obtained when water is used for the tempering cooling medium.

The effect of different tempering temperatures on microstructure and impact property of 20CrMnTi steel has been studied on Zwick/roell Amsler PKP 450 pendulum machine, SU-8020 scanning electron microscope (SEM) and optical microscope. The results shows that the impact property of 20CrMnTi steel is dramatically improved after high-temperature tempering. However, the minimum value occurs when it was tempered at 350°C because of low-temperature tempering brittlement at this degree. The SEM fracture morphology was typical dimples after high temperature tempering, and the type of fracture was ductile fracture; the type of cleavage characteristic and quasi cleavage characteristic were generated on the fracture morphology at low-temperature and medium-temperature tempering respectively, and the type of fracture was brittle.

40Cr is a kind of steel that is often used for semiaxis in heavy duty trucks, therefore high impact property of 40Cr steel is requested to adjust the heavy-duty machines working environment. In this study, the samples of 40Cr steel were heated under normal tempering temperature and quenched in air, water and oil, respectively. The experiments were carried out through charpy impact and microhardness analysis. It was indicated by experiments that water was more helpful to receive higher impact toughness as the tempering cooling medium than air and oil. At the same time, the intensity and hardness of 40Cr steel were enough to meet the heavy-duty machine semiaxis requirements.

The application of microwave technique in the roasting pyrite which contained little arsenic was described. The characteristics of microwave absorption of pyrite were investigated. The results indicated that pyrite was a good absorbent of microwave and heated rapidly to high temperature by microwave flied in a short time, causing decomposition and oxidization to removal the sulfur and arsenic. The effects of microwave irradiation time and sample mass on the removal efficiencies of sulfur and arsenic with microwave power of 4 kW and 6 kW were investigated. The big microwave power could shorten the time for removal of sulfur and arsenic. Finally iron concentrate contained 64.52% Fe, S

With the development of car ownership, peoples demand for parking Spaces is increasing constantly at the same time. As a result,all kinds of stereo garages come out. In this article, we study the push-pull driving mechanism of a tree-like stereo garage. It mainly uses SolidWorks for modeling and then uses ADAMS for kinematics simulation.In the design process we focus on the feasibility and the stability of the push-pull driving mechanism.

The microwave energy absorption of solid mineral in microwave field is the key problem of the microwave metallurgy application. For the calculation formula of absorbing microwave energy (P=2πfε0ε"E2) the fundamental data is necessary, including dielectric constant and electric field strength etc. But these basic data varies in practice due to the variation of molecular structure, overall dimension, and electromagnetic parameter of the mineral. Therefore, the theoretical calculation formula is difficult to predict the microwave absorbing ability of solid mineral [1-3]. In this paper the ability of four kinds of sulphide concentrate and their mixture coupling in absorbing microwave was investigated by intermediate medium calorimetry. The results show that the microwave-absorbing ability of chalcopyrite concentrate is the strongest, sphalerite concentrate is the weakest, and sphalerite concentrate is stronger than silica, the mixture minerals still keep their own microwave absorbing characteristics. The mass percent of strong absorbent of microwave decide the microwave-absorbing ability of mixture, and affect energy transfer between microwave and mineral.

A novel design method for stiffener layout of plate and shell structures is proposed in this paper. The method is inspired by the morphogenesis mechanism of dicotyledonous venation which is featured by hierarchy and functional adaptivity. It is expected that a optimal stiffener layout can be gradually achieved if the stiffeners extend by obeying a similar growth rule as the venation. Starting from the so called “seeds”, the stiffeners grow and branch off towards the direction that optimizes the structural performance. And the stiffeners with the minimum effectiveness to the structural performance are degenerated simultaneously. During the design process, the relative density of each element is treated as the design variable. The growth and degeneration of the stiffeners are determined by the nodal and elemental sensitivity numbers respectively. The design algorithm is programmed in Python and integrated with Abaqus software which is used as the FEA preprocessor and solver. To validate the effectiveness of the proposed method, it is applied to design the stiffener layouts of some typical structures with the objective of maximizing the overall stiffness with a volume constraint.

The combined photocatalysis and ozonation (UV/Ag-TiO2+O3) process has been investigated for its potential use for ballast water treatment by usingDunaliella salina(D. salina) as an indicator microorganism. Inactivation curves were obtained, and the mechanism was studied. Compared to individual unit processes, the combined UV/Ag-TiO2+O3tests yield enhanced inactivation efficiency. Scanning electron microscopy (SEM) measurements showed that presence of O3during UV/Ag-TiO2exposure expedited the destruction of cell structure, which was further confirmed by the formation of malondialdehyde (MDA) and decrease in chlorophyll-a (chl-a) concentration. The results suggest that UV/Ag-TiO2+O3was efficient for inactivation ofD. salinain simulated ballast water, and the accelerated destruction of cell structure was an important reason for the enhanced inactivation efficiency.

The dynamic recrystallization (DRX) behavior of GH80A superalloy was investigated by isothermal compression tests on a Gleeble1500 thermomechanical simulator. True stress-strain curves and deformed specimens were obtained at the temperature range of 1273-1473K and the strain rate range of 0.01-5s-1. Experimental results show that the stress-strain curves at low strain rate display a typical DRX characteristic. By regression analysis of experimental results, Materials constant n, activation energy Q and Zener-Hollomon (Z) parameter were determined, and the critical strain model and austenite grain size model for dynamic recrystallization were established as a function of deformation temperature and strain rate. The dynamic recrystallization kinetic model for GH80A was established on the basis of the Avrami equation.

The edible fungus industry has relatively high output rate and high added value. In the production of edible fungus, the environmental factors have great impacts. This paper studies the intelligent monitoring system for producing environment of the factory-farmed edible fungus based on the internet of things and aiming at online real-time management. The monitoring system can realize real-time surveillance and visual operation during production by dynamically regulating the environmental factors needed for growing edible fungus and early warning of the environmental parameters fluctuation with traceable history records at any time. When parameters like temperature and humidity are beyond reasonable range, warning will be sent via text messages and equipments such as air conditioners and warming devices will be automatically adjusted for on and off so as to raise management level, increase the output, improve the quality and lower the risks.

An analysis method has been proposed for the vibration analysis of the Mindlin rectangular plates with general elastically boundary supports, in which the vibration displacements and the cross-sectional rotations of the mid-plane are sought as the linear combination of a double Fourier cosine series and auxiliary series functions. The use of these supplementary functions is to solve the potential discontinuity associated with the x-derivative and y-derivative of the original function along the four edges, so this method can be applied to get the exact solution. Finally the numerical results are presented to validate the correct of the method.

This paper reviewed and analyzed the literature about the improvement mechanism of energy efficiency, examining the relationship among industrial structure adjustment, technology innovation and energy efficiency with Hubei province’s data during 2001~2010, and finding that industrial structure adjustment and technology innovation can promote energy efficiency very significantly. Even so, because the elimination of backward production capacity will be more difficult and the energy-saving space will be narrower, government should encourage citizens’ participation, pay more attention to the use of market mechanisms, and promote the development and application of the technology using preferential tax policies.

The title compounds 2-lactosylthio-3-alkyl/alkoxythieno [3,2-pyrimidin-4(3H)-ones 5 were synthesized after the alcoholysis reaction of protected 2-lactosylthio-3-alkyl/alkoxythieno [3,2-pyrimidin-4(3H)-ones 4 with the catalyst of ammonia water. The latters were synthesized from the materials ethyl 3-aminothiophene-2-carboxylate 1 and alkyl/arylisothiocyanates through the thiourea intermediaters 2 and heterocyclic compounds 3. Structural characterization of the target compounds were researched and their biological activity evaluation were underway in our laboratories.