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Springback has an important influence on the forming quality of thin-walled stainless bellows hydroforming. By developing a FE model, the stress distribution is investigated and springback characteristics of two specification bellows are addressed. The results show that: (1) For tube Φ26×0.5, the maximum circumferential tensile/compressive stresses decrease by 32% and 29.1% after springback, respectively. The maximum longitudinal tensile/compressive stresses decrease by 51.8% and 39.6%, respectively. (2) Three indices are proposed to describe the bellow profile change after springback, namely, radial displacement of crown point; axial displacement of inner point; maximum convolution width. (3) For tube Φ26×0.1, after springback, the inward shrinkage of crown point increases by 0.7%, the bellow axial elongation is 0.76mm, the maximum convolution width increases by 30.3%.

Using the fast freeze-thaw test method, we tested the loss modulus and compressive strength of steel slag-limestone powder concrete after 0,25 times,50 times,75 times,100 times freeze-thaw cycle,studied the mechanical properties and frost resistance performance after the freeze-thaw cycle. The results showed that adding a certain amount of steel slag-limestone powder does not affect the anti-frost property of concrete; established different dosage of steel slag concrete freeze-thaw damage model: y = a + bx + cx2, degree of fitting is better; large quantity of steel slag used in concrete shall be a wider range of research.

Based on the peck formula, this paper has analyzed measured data of ground surface subsidence, and get the regression curve of ground surface subsidence. Expression for degree of reliability of the maximum ground surface settlement is derived analytically by using central-point method. On the basis of a certain section of tunnel of Guangzhou subway constructed by mining excavation method, linear regression method can be effectively fitting the ground surface deformation data due to tunnel excavation. The central-point method provides a new way for reliability analysis of the ground surface settlement of shield construction.

Both open die and closed die powder compact forging can be used for the consolidation of Ti and pre-alloyed Ti 6Al 4V powders produced by a hydride-dehydride (HDH) process. The approach used is initial cold or warm compaction into cylindrical shapes, or into a specific pre-form shape appropriate for achieving a particular final forged shape. The economic benefit is near net-shape processing with minimum machining required after forging. Manufacturing costs are also minimised by forging a compact, with a sufficiently high enough density, in air, without a protective atmosphere. The challenge, from a manufacturing point of view, is the operation of a manufacturing route which gives rapid and qualified compaction to meet production demands and batch sintering to achieve a high enough density prior to final forging to shape. In addition to this the final product has to have the right level of mechanical properties. This paper reviews some key findings from powder compact production, through to sintering and forging. These will be presented in terms of alpha-beta phase distribution in the microstructure, the degree of porosity, heat treatment and their effects on mechanical properties.

The design quality of the nuclear power plants (NPPs) has a direct impact on the operation and maintenance, which involves the safety and reliability of NPPs. Planning and development of the maintenance requirements of system and equipment in initial design stage of NPPs, and determination of reliability maintenance strategy compilation methods enable to fulfill good connection between design and operation of important value. After investigation and analysis, with a combination of reliability analysis method, experience feedback and common analysis approach, the methodology of reliability maintenance strategy compilation in design stage of NPPs has been initially established. And such methodology not only meets the maintenance requirements of system and equipment in design stage, but also enables to check the rationality and operability of process design from the maintenance implementation level, at the same time, it has great value in application regarding improving operational reliability of NPPs and avoiding non-essential major modification during operation of NPPs.

Titanium alloys have a number of features which make them attractive for use in aerospace, marine and chemical engineering, biological engineering, etc., due to their advantage of low density, high strength, and excellent corrosion resistance and biocompatibility. In this paper, Ti-6Al-4V (Ti-64) rods were prepared by vacuum sintering titanium alloy powder compacts at 1300°C for 2h and then hot extruding the as-sintered Ti-64 alloy billets at 1150°C in air. The microstructure and property changes, after vacuum sintering and hot extrusion, were investigated. The results showed clear evidence of porosity and a coarse lamellar microstructure in as-sintered Ti-64 alloy billets. Tensile testing of as-sintered material gave yield strength, ultimate tensile strength and ductility values of 850MPa, 985MPa and 2%, respectively. After extrusion at 1150°C, no obvious pores could be seen in the microstructure of as-extruded Ti-64 alloy rods and the lamellar microstructure was significantly refined, and the mechanical properties were significantly improved. The yield strength, ultimate tensile strength and the ductility reached 1130MPa, 1245MPa and 4.5%, respectively. Compared with the mechanical properties of Ti-64 alloy rod prepared by extruding a hot pressed Ti-64 alloy billet (1300°C for 5min, argon protective atmosphere) in air, the ductility of the Ti-64 alloy rod studied here is lower. The fracture characteristics of as-sintered and as-extruded Ti-64 alloy rods have also been investigated.

The real time synchronous sampling of large basic data information and the networking information sharing have laid necessary foundation for smart substation advanced application. The advanced application of smart substation is the multi-index optimization analysis and control strategy research which based on digitization of information transmission and networking of information sampling. This paper aimed at health state analysis and control strategy research of substation equipment and network environment, which based on the theory of multi-element data analysis and double network and double measuring and control.

Freeze-dried gelatinization glutinous rice starch (FGGRS) was prepared, characterized and evaluated. The functional properties of native starch and FGGRS were studied, respectively. Scanning electron microscopy (SEM) suggested the structure of FGGRS is looser and more porous, and the surface is rough and scaly. Due to the rapidly cooling process, the movement of starch chains was curded and X-ray diffraction (XRD) showed the peak strength of FGGRS is lower than the original, presented as a diffuse state and indicated that it is a V-type structure. Its particle was determined by mastersizer 2000 particle size analyzer and resulted in particles with a mean size of 11.33μm. Rheological tests confirmed FGGRS is pseudoplastic fluids and demonstrated that it belonged to shear thinning system. FGGRS presented a lower apparent viscosity and performed better freeze-thaw stability. The light transmittance of FGGRS was 27.67%, and presented a better transparency. In addition, due to its formation of new crystal types and its loose microstructure after lyophilization the cold water solubility of FGGRS is excellent.

The general design of virtual maintenance platform based on 3D simulation is given to solve the difficulty of maintenance training for large equipment. Firstly, primary functions of platform are defined by comparing common platform with application system. Secondly, component structure and interaction structure of platform are designed based on common thinking of subsystem-serverice. Finally, technology systems of platform including common simulation framework and training basing on 3D simulation are also presented to realize simulation software. It will provide beneficial reference for maintenance training simulation of other similar large weapon equipment.

Aim at the multi-faceted nature and universality of the EMC problems in high-speed PCB, based on a three-line coupling model and considering the influence of via holes caused, board-level EMC problems of PCB were researched on point for point. In this paper, the research and simulation were launched by a kind of software named Hyperlynx, and a 6-layer PCB model was built and used. Our Research was focused on the EMC problems existed in hierarchy and layer medium. On the basis of the simulation results, and combined with previous experience in the PCB design, some effective measures for improving EMC in high-speed PCB design were summarized, which could be taken as a clearly reference in design of high-speed PCB.

Bis (p-aminophenoxy) dimethylsilane (p-APDS) was prepared by the reaction ofp-aminophenol or 4-acetamidophenol with dimethyldichlorosilane in the presence of triethylamine or pyridine through four different means. The structure of diamines was examined by melting point apparatus, FT-IR and nuclear magnetic resonance apparatus1H-NMR. The productivity, process and cost of four means were compared. The results showed that benzene as a solvent, triethylamine as acid,p-aminophenol and dimethyl dichlorosilane at 40°C for 4h is the most economical and reasonable process for synthesis of bis (p-aminophenoxy) dimethylsilane (p-APDS).

Organic phosphorus in sediments of lake Gehu in China was investigated and researched via two methods: chemical fractionation and phosphorus-31 nuclear magnetic resonance spectroscopy. Results of chemical fractionation suggested that concentration of each organic phosphorus species in different sediments may varied highly since different condition, but showed a rank trend : residual Po> HCl-Po> Fulvic-Po> Humic-Po>NaHCO3-Po. Labile and moderately labile Po , regarded as potential P , contributed to 33.6% to 64.6% relative to total Po, which can be degraded for phytoplankton. 31P-NMR results suggested that the rank order of P species presented in NaOH-EDTA extractants of sediments: orthophosphate> monoester-P> DNA-P> pyrophosphate-P, and polyphosphate and phosphonate were almost not detected.

A composite TiO2 photoelectrode structure is explored to optimize the dye-sensitized solar cell (DSSC) properties. The composite TiO2 photoanodes consist of two nanoparticular TiO2 layers with different size and thickness. The impact of film thickness on the performance of DSSCs was also investigated. In the optimized composite photoelectrode structure with large sized TiO2 nanoparticle as light scattering layer, the significantly improved performance of DSSC with 25% increase of current density and 13.1% increase of conversion efficiency was experimentally demonstrated.

This paper introduces a kind of dust removal device-passive sprinkler dust car which is often used to improve the environment and to prevent dust underground. The function, working principle and basic structure of passive sprinkler dust car underground as well as how its main parts work are mainly described in this article. Moreover, the relationship between the spray parameters and the efficiency of reducing dust is studied by adopting the combination of experiment and theoretical analysis methods in order to obtain higher efficiency of reducing dust in this paper.

In order to attenuate the deformation of spray boom, a finite element model built based on ANSYS, according to the reasults of numerical modal analysis and modal texting, the reliability of the finite element model was affirmed. Then, an isolator was introduced between spray boom and frame, a frame-isolator-spray boom model was built in ADAMS. The effect of the isolators which have different parameters was research, the reasult shows: The isolator has much effect on attenuating spray booms deformation, the stiffness of isolators spring dampers has little effect on spray booms deformation, but the damping of isolators spring dampers has effect on spray booms deformation.

It is introduced the problems that coal mines in China are facing now, including the heavy taxes, the enormous amount of workers, the inefficient supervision and being easily effected by the policy. It is suggested that the government should make some policy which are good for the sustainable development of coal mine, and the government should encourage coal mine to adjust their industry in a scientific way, also it is good to reward the coal mine which are run in a low carbon economy model. During the process to build a sustainable coal mine, attention should be paid that it is a course of events which couldnt be accomplished immediately, time is needed to finish the goal of sustainable development of coal mine in China.

In this article, according to WenShuHua and Zhangxueniang fractal model, we point out the deficiency. Based on the fractal theory and Zhang, Wens contact stiffness fractal model, this paper puts forward Gamma distribution of rough joint surface normal contact stiffness. This paper considers micro convex body for ellipsoid, contact area for elliptic. This is slightly convex body for sphere hypothesis is more close to the actual situation. At the same time by using statistics theory, considering the contact ellipse long, short axis a and b are greater than zero, the assumption of a and b to two-dimensional Gamma distribution, it is more suitable for engineering practice.

The aluminum alloy automotive wheels are widely used and their quality safety is vital. So their structure design should be optimized. Based on the wheel bending fatigue test and the analysis of aluminum alloy automotive wheel's structure characteristics, the wheel's load was discussed and the analysis of the wheel was done by using Solidworks and ANSYS. The analysis result provides scientific basis for the optimization design of the aluminum alloy automotive wheels.

According to the present state that traditional regular repair methods are always adopted for mining equipment maintenance, this paper puts forward a method of installing various sensors on the equipment which are combined with computer and signal analysis technology so as to realize on-line monitoring, fault prewarning, and remote release. This paper analyses the common faults of mine ventilator and their characteristics, selects the vibration sensor and its mounting points based on the characteristics of the fault signal, selects the signal acquisition cards based on equipment operating conditions and analysis parameters accuracy, builds up the hardware and software platform, completes the design of system function module and data flow, and achieves modularization programming for the whole software system by combining labVIEW and database. This system realizes the condition-based equipment maintenance so that informatization and automation can be achieved in equipment management.

Manganese oxide (Mn3O4) catalyst was prepared by decomposition method and characterized by X-ray powder diffraction (XRD) and fourier transform infrared spectrum (FTIR). Catalytic activity of Mn3O4was tested by the oxidation of toluene to benzoic acid with molecular oxygen in liquid-phase and solvent free conditions. As a result, 45% conversion of toluene and 91% selectivity of benzoic acid was achieved. It is proved that Mn3O4catalyst can use several runs without decrease of activity.

The paper puts forward a method of ventilator running state prediction which is based on EMD and Neural Network, which aims at ventilators non-stationary vibration signals. First of all, vibration data are decomposed into eight intrinsic mode signals and one residual quantity by EMD. Then Neural Network is adopted to predict the decomposition components and reconstruct them. Finally, the final prediction results are achieved. In this paper, the ventilator vibration signals of Tangshan Iron and Steel Group Coking Plant from March 1, 2012 to July 1, 2012 are used as the research data. Comparative study method is adopted to compare this prediction method with direct Neural Network prediction in terms of results, which shows that this method has better accuracy.

GeSbTe (GST) thin films were deposited on Si substrates using electron beam evaporation system and then annealed in nitrogen atmosphere at different temperatures. X-ray diffraction (XRD) and Atomic Force Microscope (AFM) measurements were used to characterize as-deposited and annealed films. Annealing treatment was found to induce changes in microstructure, surface roughness, grain size and so on, indicating that with the increase of annealing temperature, the amorphous state of GST materials change first to face-centered-cubic (fcc) phase state and finally to the stable hexagonal (hex) state. Amorphous Ge1Sb2Te4film will crystallize under laser irradiation. With increasing irradiation time or irradiation power, the degree of crystallization increases. The Raman spectra of thin film shows three peaks after laser irradiation, the peaks can be attributed to the key vibrations which were caused by crystallization. With the irradiation time increases, the peaks shift.

At present, most factories choose cutting parameters only depending on experience or handbooks in production. To improve the intelligent level of cutting parameter selection, Case-Based Reasoning (CBR) is used to search rational cutting parameters. The structure of a CBR-based cutting parameter selection system is presented and its functional modules are discussed. CBR-based cutting parameter selection system is mainly composed of case base management system, cutting parameter database management system, application, interface, etc. A complete case is composed of four parts, i.e., objectives, initial conditions, constraints and results. The system adopts hierarchical searching method in combination with nearest neighbor method. It provides a scientific approach for selecting cutting parameters in actual production.

Malthusian population growth model is not applicable to the real world situation in most cases, since the simplifying assumptions are too ideal. In this article, we will generalize the classic population growth models by Stochastic differential equations, and get the extended models appealed to the real world better as well. When modeling the environmental perturbation by white noise process, we get an advanced model .

In order to transfer heat as much as possible through a unit area in unit time, this paper introduces three enhanced heat transfer structures, namely microchannel, open-celled metal foam and open-celled sintered porous metal. From two aspects of the heat transfer performance and the flow resistance, this paper reviews their research progress. Among three kinds of enhanced heat transfer structures, open-celled sintered porous metal has the best heat transfer performance, followed by open-celled metal foam and micro-channel. While, the sequence of the pressure drop of three kinds of enhanced heat transfer structures is in the reverse order. Thus, Enhanced heat transfer Structures with good heat transfer performance and small pressure drop are the future research direction.

In view of the requirements on multi-target information interaction and implementing complicated control strategies among different ECUs in hybrid electric trucks, an information integration control network based on CAN bus is proposed. A HCS12 dual-core processor MC9S12XDG128 is adopted to design an information integration module for sensor signal acquisition and data transmission in the network. Application layer protocol is defined to optimize the message transmission mechanism. Meanwhile, Rate Monotonic Analysis (RMA) method is adopted to analyze bus load rate and real-time performance of the network. Bench test results have shown that the designed information integration control network for hybrid electric trucks owns good real-time performance and is reliable to implement communication and control tasks with low bus load rate.

Antireflection of silicon surface is one key technology for manufacture of efficient solar cells. The noble metal assisted chemical etching Si wafer can quickly produce a black Si surface with a high porosity in HF-H2O2-H2O solution at room temperature. The pores formed are straight and vertical to the surface of Si. The porous Si surface exhibits a reflectivity of 2 % in the range of 200-1000 nm, which shows that this process is beneficial to improve the conversion efficiency and to decrease the cost of Si solar cells.

The effect of hydrogen peroxide (H2O2) of low concentration on thermotolerance of tall fescue (Festuca arundinacea cv. Barlexas) and perennial ryegrass (Lolium perenne cv. Accent) was studied following a foliar pretreatment with 10 mM H2O2. Turfgrass quality, relative water content (RWC), oxidative damage were measured in both cool-season turfgrass cultivars under heat stress (38/30 °C, day/night) and control normal temperature (26/15 °C, day/night). Pre-treated plants of two cultivars showed the lower MDA and H2O2 levels and the higher turfgrass quality and RWC under heat stress. Our results demonstrated that exogenous H2O2 of the low concentration improved the thermotolerance of tall fescue and perennial ryegrass by inducing the antioxidative enzyme activities and alleviating the oxidative damage.

Waterborne epoxy resin was prepared through introducing hydroxyl and carboxyl groups in the main chain of epoxy resin with the bisphenol epoxy resin, toluene diisocyanate and 2,2-dimethylol propionic acid by self-emulsification. Analyzed the structure of products via Fourier transform infrared spectrometer, then to test the water-soluble and stability. And the best conditions of reaction were determined through studying the influence of material ratio, reaction time and reaction temperature to products. The result shows that the synthesized waterborne epoxy resin has favorable stability and water-dispersion.

The effect of an divalent electrolyte Ca2+ on the flocculation of two different concentrations of anionic surfactant Sodium Dodecylbenzenesulfonate (SDBS) with Al3+ has been investigated at different molar ratios Al3+ to SDBS at 298.15 K. The results showed that the flocculation characteristics of 0.01 mol•L-1 SDBS (above the critical micelle concentration CMC) and 0.001 mol•L-1 SDBS (below the CMC) were obviously different with an increase of dosages of Al3+. The z-average size of flocculate of 0.01 mol•L-1 SDBS with Al3+ decreased particularly with the pre-addition of Ca2+，It suggested the formation of the complexion Ca(SDBS)2. At optimization flocculation areas at 298.15K, pH values were all around 3.5 in the flocculation systems SDBS/Al3+ and Ca2+/SDBS/Al3+ whether the SDBS concentration above or below the CMC. The pre-addition of Ca2+ slightly affected other flocculation parameters of SDBS/Al3+ systems such as zeta potential, surface tension, conductivity and pH.

The effect of hydrogen peroxide (H2O2) of low concentration on thermotolerance of tall fescue (Festuca arundinacea cv. Barlexas) and perennial ryegrass (Lolium perenne cv. Accent) was studied following a foliar pretreatment with 10 mM H2O2. Antioxidative enzymes activities and antioxidant content were measured in both cool-season turfgrass cultivars under heat stress (38/30 °C, day/night) and control normal temperature (26/15 °C, day/night). While activities of catalase(CAT), guaiacol peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione-dependent peroxidases (GPX) were enhanced by H2O2pretreatment during heat stress. APX, GR and GPX activities were significantly enhanced during heat stress. These were likely the most important antioxidative enzymes in tall fescue and perennial ryegrass protecting plants against heat stress. The thermotolerance was also concomitant with an increased glutathione pool, as evaluated by the significant increase of the total glutathione pool in two pretreated cultivars. The increase of POD, CAT, APX, GR activities and significant increase of GPX activity prior to the initiation of heat stress in pre-treatment plants suggested a possible role for H2O2as a signaling molecule protecting them against the subsequent heat-induced damage.

Terminal sliding mode control (TSMC) was designed with introduction nonlinear function into sliding hyper-plane, which makes tracing error converge to zero in finite time. The standard TSMC (STSMC) control and non-singular TSMC (NTSMC) control was designed for an uncertain two-order nonlinear dynamic system, the sliding function and controller of STSMC control and NTSMC control are designed respectively, also the finite time of arrival was analyze. The stability was proved with Lyapunov theory, the performance comparison of STSMC and NTSMC was simulated with conclusions that STSMC control and NTSMC control are all feasible control for nonlinear system, STSMC control exist singular problem, but NTSMC control without singular problem, with sliding surface and control law with different parameters, the control characteristic can realized, which was suitable for special control system.

Because of the special physical and chemical character, TiO2nonmaterials have been applied in many fields and bring enormous progress to people’s life. However, a new problem has turned to be the focus of people’s attention, that is, whether TiO2nonmaterial may bring about harm to the organism. This paper introduces three contacts (breathing contact, alimentary canal contact, shin contact) between TiO2nanometer materials and people, and then recommends the safety affection of TiO2nonmaterial for people. In the end there are some protection measures of TiO2nanometer dust which may be harmful to our health.

Tobacco stem and tobacco dust made reconstituted tobacco paper-base with a paper-making method, effect of extracted and refined on tobacco stem and tobacco dust, particular effect of tobacco stem and tobacco dust ratio on physical properties, chemical composition and microstructure of reconstituted tobacco paper-base were studied. The results indicated that the content of water soluble sugars, total alkaloid, chloride, total nitrogen of the extracted tobacco stem and extracted tobacco dust were decreased, content of holocellulose was increased. With decreasing of tobacco stem pulp ratio (increasing of tobacco dust pulp ratio) of reconstituted tobacco paper-base, there was rapid decrease in tensile index, tear index, bulk and air permeability of reconstituted tobacco paper-base. The scanning electron microscopy (SEM) showed that tobacco dust ratio more than 30%, bulk of reconstituted tobacco paper-base decreased significantly. Content of water soluble sugar, total alkaloid, chloride and total nitrogen of tobacco reconstituted paper-base decreasing significantly after paper-making.

Tobacco stem and tobacco dust are the major raw materials in the reconstituted tobacco production. The extraction of the components from these materials is one of the most important procedures in making the reconstituted tobacco sheet. In this paper, we reported an approach of three-stage counter current extraction to transfer the components from tobacco stem and tobacco dust. The results showed that the extraction ratios for tobacco stem and tobacco dust were 40.2% and 54.2%, respectively. The testing results on the extracted tobacco stem and tobacco dust showed that the overall extraction ratios of water soluble sugars, total alkaloid, and chloride in tobacco dust were 89.3%, 90.5% and 100%, respectively; and the overall extraction ratios of water soluble sugars, total alkaloid and chloride in tobacco stem were 59.3%, 60.3% and 76.2%, respectively; The contents of total nitrogen in tobacco dust and tobacco stem were basically no change after each extraction. Lower extraction yield and higher extraction ration were obtain by three stages extract than those by single stage extract.

This article highlights the poly (m phenylene isophalamide) fibrous membrane (PMIAFM) fabricated by electrospinning technique, and the effects of the process variables such as applied voltage and concentration of the PMIA solution on the morphology and properties of the PMIAFM were addressed. The morphology and structural analyses on electrospun nanofiber membrane using apparatus e.g. scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). The results showed that the membrane with better morphology was derived from 7wt% of the PMIA, an applied voltage of 18kV, of which the diameter ranged from 100nm to 1μm; within the spinnable concentration range, the concentration of the PMIA solution was proportional to the size of the fiber; and if the voltage beyond or miss the normal figure, namely 18-25kV, a instable jet would emerge.

Multiphase transportation of the wellhead product in a single pipeline is widely used in oilfields. The oil samples transported in the multiphase pipeline are often live oils saturated by light alkanes. To support the multiphase pipelining more efficiently, in this paper, the solubility and rheology of Chang10 live crude oils are studied at the pressures range from 0 to 2.0 MPa. It was found that the dissolved gas in the live oils is mainly composed of methane (32.70 vol% at 1MPa), ethane (19.43 vol% at 1MPa), propane (21.42 vol% at 1MPa) and C4+ component (22.50 vol% at 1 MPa). The gas-oil ratio, Rs, of the live oils increases rapidly with the increase of saturation pressure. However, the effect of saturation temperature on Rs is very small. The pour point, abnormal point, WAT, viscosity/equilibrium viscosity and yield stress of the live oils decrease obviously with the increase of saturation pressure, meaning that the rheological properties of the live oils improve greatly by gas dissolving. The rheological properties of the live oils are improved mainly by the dilution effect of the dissolved gas.

In this research a laboratory model recirculating cooling water system was applied to investigate the effects of four kinds of inorganic ion concentrations on extracellular polymeric substances (EPS) content, the ration of proteins and polysaccharides ratio in EPS (PR/PS) and dehydrogenase activity (DHA) in the attached biofilms. The results showed that the low Na+ concentration was beneficial to EPS production and biofilms DHA. With Ca2+ concentration increasing, EPS content first increased and then decreased as a whole. Mg2+ showed no obvious effect on biofilms EPS content, while had the effect on PR/PS and DHA. The increase of Fe3+ concentration was beneficial for EPS formation and DHA when Fe3+ concentration was below 1.5 mg/L.

The Ag-assisted electroless etching of p-type silicon substrate in HF/H2O2solution at room temperature was investigated. The porous silicon layer was formed in a mixed solution of H2O2and HF by using screen-printed Ag front electrodes as the catalyst. And influence of the different concentration etching solution (HF and AgNO3) on the porous silicon layer was study by scanning electron microscopy (SEM). Through investigation of the track of catalyst particles, it was shown that Ag really catalyses the etching of silicon underneath Ag particle.

This article introduces the application of crosshole sonic logging in foundation pile integrity detection and the basic theory and application of crosshole sonic logging, and narrates the detection technology and way to judge detection results by engineering projects.

Aiming at the difficulty in crack detecting for bridges, a wireless crack detecting system based on machine vision and RC model helicopter was designed and realized. This system used a wireless camera to capture the surface images of bridges from the direction of below, then images were transmitted to the host computer by 2.4 GHz wireless communication. Edge image of crack can be gained after the image processing program carried out smoothing filtering, adaptive binary and edge extraction for original images of bridge. Image processing program adopted Hough transform to extract the characteristic parameters of bridge crack in edge images including length, width, shape and location of crack. The result of accuracy verification test shows that the relative error of this system was in the range of ±5% and it satisfied the requirements of early crack detecting for bridges.

Benzyl alcohol is used to react with isophorone diisocyanate at different temperatures. Dibutyltin dilaurate is used as catalyst. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of different isocyanates groups are respectively calculated out, which are very useful to reveal the reaction mechanism.

The urethane reaction kinetics of 1,2-propanediol and 1,3-butanediol with phenyl isocyanate are investigated in toluene. In-situ FT-IR is used to monitor the reaction to work out rate constant. The urethane reaction has been found to be a second order reaction and is largely accelerated with triethylamine as catalyst. Furthermore, the rate constants are different between initial stage and final stage when triethylamine is used as catalyst, which belongs to different hydroxyls in asymmetry diol. However, when there is no catalyst in the reaction system, the rate constant is the same. That is, there is no reactivity difference for hydroxyls in asymmetry diol. Moreover, 1,3-butanediol is more active than 1,2-propanediol when reacting with isocyanate.

In this paper, TZS88 aluminum alloy mechanical properties of three months of natural aging is tested, the microstructure and the strengthening mechanism is studied by the application of optical metallographic microscope and scanning electron microscopy. The results show that TZS88 aluminum reinforced mainly caused by solid solution strengthening, aging strengthening and dispersion strengthening, and as such its tensile strength, hardness and elongation in the natural aging have reached ZQSn6-6-3 bronze level, the microstructure are compounds which included α(Al) solid solution matrix + Sn + s, θ, T, ε etc.

In this paper, the WC-5TiC-10 Co mixture mixed by WC2.96μm, (Ti, W)C 2.52μm and Co2.38μm and prepared by high-energy ball milling. The result shows: After 60h’s ball milling the powder began to reunite more and more as the time extended . The average grain size of powder is 50 nm after144h. After 1300°C~1400°C vacuum-sintering the hardness of the sample is 94.8 ~ 95.4HRA. 4.2 ~ 5.2 HRA higher than the traditional cemented carbides with the same composition. After 1400°C vacuum-sintering the compressive strength and flexural strength of cemented carbides is 2060 MPa and 1200 MPa. Slightly less than the traditional cemented carbides with the same composition.

For the complex status of fluid flow in stator radial ventilation ducts of large turbo-generator, the temperature distribution of stator is dramatically affected by the flow status of cooling medium in stator ventilating ducts. In this paper, a new ventilating ducts structure in stator is investigated. According to fixing a wind deflector on the stator teeth adjacent to the ventilation ducts, the fluid flow status of cooling air is changed flowing in stator ventilation ducts. For this reason, the effect of heat transfer in stator is changed. Taking an air-cooled turbo-generator as an example, considering the characteristics of fluid flow and heat transfer in turbo-generator ventilation system, the three-dimensional fluid flow and heat transfer coupling model is established. Using finite volume method, three-dimensional fluid field and temperature field control equations are coupling solved. Based on this, the velocity distribution in ventilating ducts is obtained. Besides that, the velocity distribution is studied with the cooling air flows into radial ventilation ducts at different incident angles. The influences of wind deflector and incident angles on the fluid velocity and temperature distribution are analyzed. Based on that, some useful conclusions are obtained.

Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Toluene is used as solvent and 1,4-diazabicyclo[2,2,2]octane is used as catalyst. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 26.4 kJ•mol-1, 23.6 kJ•mol-1and -186.6 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 90.9 kJ•mol-1, 88.2 kJ•mol-1and 20.2 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

The eddy current loss of stator strands in the in-phase slot and out-phase slot was calculated by the finite element method (FEM). 3D static heat transfer equations and equivalent variation equations of large turbo-generator under the Cartesian coordinates system were given. The stator temperature field of large turbo-generator was calculated by using 3D FEM, and the influence of thermal conductivity reduced due to main insulation aging both in in-phase slot and out-phase slot on the stator was analyzed. The obtained conclusions will provide theoretical basis for fault prediction and fault diagnosis.

Phenyl isocyanate is used to react with 1,2-propanediol in different temperatures. Toluene is used as solvent and triethylamine is used as catalyst. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction are calculated out, which are 74.1 kJ•mol-1, 71.3 kJ•mol-1 and -30.5 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.