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Nuclear power plant engineering quality is the security of nuclear safety. The main danger source of nuclear power plants is the nuclear island. Once the project quality uncontrollable, radioactive nuclear fuel could be harm to human and environmental in the nuclear power station trial operation or production cycle. So this paper analysis the effect factors of the nuclear power construction quality, and concludes it must to be control strictly the project construction quality of the nuclear power plant, and use the prevention and control method to set up quality defensive barrier to eliminate the problems of engineering quality.

A controlled release composite has been prepared by intercalation of sodium paeonolsilate (PAS) into Mg/Al layered double hydroxide (LDH) with the molar ratio (M2+/M3+) of 2:1. The powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) confirm the intercalation of PAS into the galleries of LDH. The chemical composites of PAS-LDH were revealed by elemental analysis. Release tests of the PAS-LDH composite showed that no burst release phenomenon occurred at the beginning stage and a high release ratio of PAS (89.8%) was obtained, exhibiting controlled release behavior. Furthermore, the parabolic diffusion model was used to simulate the release kinetics of PAS from the LDH carrier, indicating that the intraparticle diffusion via ion-exchange is the rate-determining step in the release process. It is significance in this work for introducing the PAS-LDH composite to develop antifouling materials with long-term activity.

Using the pulse excitation method, the elastic modulus of resin carbon was measured with different carbonization temperature. Micro structure of resin carbon was analyzed by XRD. Porosity, bulk density and true density of resin carbon was measured and calculated. The results show that the elastic modulus of resin carbon is 2.51GPa under 700°C carbonized, and is 2.92GPa under 1300°C carbonized. From 700°C to 1300°C, the elastic modulus of the resin carbon increases firstly and then decreases. The XRD analysis shows the crystal structure of resin carbon tends to regularization with the increase of carbonization temperature. The porosity of resin carbon is 14.% under 700°C carbonized, and is 13.38% under 1300°C carbonized. Considering XRD and porosity, the rise of elastic modulus of resin carbon from 700°C to 1000°C attributes to the incomplete pyrolysis of resin, reduction attributes to the graphitization of resin carbon from 1000°C to 1300°C.

This paper first introduces the basic concept of the CSG (cemented sand and gravel) dam construction. It then puts forward a new quality control method by inspecting the in-situ P-wave speed of CSG as an alternative to the conventional specimen compression tests. Through an extensive experimental program, it is found that there is a good correlation between the compressive strength and P-wave speed of CSG, which makes the P-wave speed measurement potentially an effective and efficient quality control measure to evaluate the CSG strength on site.

The temperature and thermal stress of different air ways of purging plug were comparatively analyzed by means of finite element method. Combined with the physical properties of the air ways of purging plug, a set of field tests were carried out for the optimum structure. The results showed that the structure of air ways of purging plug had great impact on the thermal stress. In service process, the damage of the air way was mainly caused by tensile stress in axial direction. By evenly distributes the tensile stress in axial direction, the stress decreased by 40% compared with the original one, and thermal shock resistance of purging plug D with circular slit structure has been improved and also proved in the field test.

As a universal component connection and power transmission gear box, is widely used in the modern industrial equipment, but also an easy failure parts, has a great influence on the running state of the working performance of the whole machine. This paper first analyzes the gear box fault form and characteristics, the gear box fault diagnosis method based on vibration signal analysis, and analysis of the vibration signal processing method for gear vibration signal analysis in time domain, including parameters, resonance demodulation method and cepstrum analysis method. Then using Visual C + + language and data acquisition card for real-time acquisition of gearbox vibration data software, including parameter setting, data acquisition module, signal real-time display module and data storage module. The data acquisition program is developed, the actual acquisition of gearbox vibration data of gear fault and bearing fault, and analyzed.

The power and brake performance of wheeled construction machinery are separately detected on different test equipment in present chassis detection line. A new method is put forward in the veiw of high cost, large area occupied and low treatment efficiency of the traditional line. A DC dynamometer is provided as the power absorbing device and the reverse drag device to combine the two separate platforms in the proposed method, and the mathematical model of DC dynamometer is built based on the principle of chassis performance test. The parameter of dynamometer is determined by calculating, and power and brake detection integration of the wheeled construction machinery is achieved on the integrated test platform.

In order to improve the machining accuracy of workpieces, we developed the magnetorheological finishing system. Taking the measurement and control system of the magnetorheological finishing system as the research target, we introduced the overall function design of the measurement and control system firstly, and then introduced the function of each module, including the multi-module control for circulatory system, parameter setting for the circulatory system, condition monitoring for the circulatory system, ribbon calibration, tool setting, anti-collision control of the finishing wheel and finishing spots collection. The developed measurement and control system of the magnetorheological finishing system can effectively guarantee the high-precision machining of machine tools.

In this paper, the function projective synchronization of complex dynamical networks is investigated. Based on the stability theory for fractional-order differential equations, an effective control scheme is proposed to achieve function projective synchronization for complex dynamical networks. Corresponding numerical simulations are presented to show the effectiveness of the proposed synchronization criteria.

Taking the designed magnetorheological finishing system as the research target, the design method for lower PLC program of the system was introduced firstly, and the main control functions were introduced, including the MCP control, the hand vein control, the move axis control, the alarm control, the circulatory system control and the auxiliary function control of the machine tool. Then, the upper software system integration method was introduced, including the structure of upper software program, the state transition between the control functions and project preparation and performance optimization for the polishing solution. The designed human-computer interface can guarantee high-precision machining of machine tools.

Monitoring servers' power is very important, and a design is present for solving existed issues. Building a wireless network with Zigbee technology, there are major modules:End Device with chip CC2530, Zigbee Router with chip CC2530 and CC2591, Zigbee coordinator with chip CC2530 and CC2430.

In order to satisfy the magnetic rheological polishing process, we established a measurement and control system based on SIEMENS 840D numerical control system. The structure of the system are introduced in detail, i.e. the four component modules, the seven component units establishing the hardware platform, and the three component parts establishing the electric control system design. The measurement and control system presented in this paper provides guidance for the relevant products.

In order to process the optical crystal materials with high precision, we developed a magnetorheological finishing prototype. This paper introduces the structure and functional theory of the finishing prototype, i.e. the overall design frame of the control system, the framework level design method of the control system and the development method of the control system. In addition, this paper introduces the function of each module, the design method of each level and the machining principle of the control system in detail. This control system can accurately check the removal amount of the workpiece, and provides reference for the design of the related control system.

Basing on field data ofQuercus glandulifera var. brevipetiolataandQuercus variabilismixed forest (MF),Quercus aliena var. acutiserrataforest (QF1) andQuercus aliena var. acutiserrataforest (QF2) at different altitudes of Baotianman Mountain, we revealed biomass C storage of tree organs for each forest, and the distribution patterns of biomass C in different forests were also indicated. We found that total biomass C of forests decrease as altitude increase. The species mixed forest store more biomass C than others. However, biomass C storages at the scale 5m×5m vary dramatically for most of the plots. Biomass C storage in organs follows the law trunk>branch>root>leaf for all the three types of forests. It is interesting that biomass C of both above̶ and belowground are MF>QF1>QF2, whereas the ratios of aboveground/belowground biomass C are QF2 > QF1 > MF. Our results indicate that both altitude and forest type are key influence factors of forest biomass C in Baotianman Mountains.

Experiments for studying the shrinkage of concrete cured under three conditions were designed, and the impact of different curing conditions on the 28-day shrinkage and 180-day long-term shrinkage of concrete was researched. The results are as follows: There are significant influences of different curing conditions on shrinkage of concrete; The variation rule of 28-day shrinkage of concrete is consistent with that of 180-day shrinkage of concrete, the shrinkage of the concrete cured under standard condition is less than that cured under indoor natural condition, and larger than that cured under totally enclosed condition; In addition to mixing polypropylene fiber and expansive agents to optimize the proportions of concrete mix in the manufacturing process of concrete, adequate curing, after placing, is quite necessary for effectively controlling the shrinkage development of concrete, reducing the risk of concrete cracking and improving the quality of concrete structure.

In this investigation, a measurement system based on machine vision applied for auto-hubs eccentricity between the center hole and the pitch circle of bolt holes was proposed. The measurement system was integrated by a CCD camera with a telecentric lens, a diffuse bright-field back light illumination system, a rotating platform, a rotating encoder and an industrial computer. The camera was fixed at a suitable location from the rotation center, which ensured that one bolt hole and a part of the center hole could appear in its visual field. All bolt holes were shot when the auto-hub was rotating, while a rotary encoder recorded these angles. Then a global image of the auto-hub could be tiled by these pictures. An image-processing algorithm integrating morphology, circle fitting, affine transformation and edge extracting was used to measure the auto-hubs eccentricity. According to the measurement of a standard block that had 50um-eccentricity and was manufactured by WEDM-LS (Wire Cut Electrical Discharge Machining-Low Speed), the maximum deviation between measuring value and real value was less than 0.013mm, eccentricitys standard deviation was 0.0035mm and the standard deviation of eccentricitys direction angle was 2.37°. Meanwhile the experimental data of real auto-hubs gave an eccentricitys standard deviation less than 0.013mm and a direction angles standard deviation less than 2.1°.

A machine vision based measurement system of auto-hub’s eccentricity between the center circle and the pitch circle of bolt holes is proposed in this article. Pictures of all bolt holes are shot when the auto-hub is rotating. The eccentricity can be calculated by tiling these pictures to a global image. There are some error factors in the system such as run-out of rotation center, inclined platform, rotation angle error, tilted auto-hub’s surface, roundness of the center hole and angle between bolt holes uneven. Mathematical models of these error factors are studied. By stimulating all these error factors, run-out of rotation center has the greatest impact and some key parameters are given in mechanical system design.

The deformation measurement of loaded Three-Ring Chains is of great significance for production safety. In this study, a machine vision system for measuring deformation of loaded Three-Ring chains is developed. The measuring system uses a back diffuse light illumination and a CMOS industrial camera. A measurement algorithm based on sub-pixel edge extraction, contour segmentation, contour fitting is designed. The system can measure the long axis length of outer diameter (OLL) of the each ring of loaded three-ring chains. For the visual system, the absolute error is 0.004 mm, the standard deviation is 0.0024 mm. For the whole system, the absolute error is less than 0.015 mm, the relative error to the full-length of chain is less than 0.25 ‰, the relative error to the total amount of the stretching deformation is less than 2‰.

The rational allocation of tolerances is the key to reduce production costs and guarantee the performance. In this paper, in the premise of ensuring the performance, manufacturing cost minimization of assembly parts is set as objective function, and an adaptive genetic algorithm is proposed to optimize the design of tolerance allocation. The adaptive mechanism is introduced mainly for crossover operator and mutation operator to overcome the traditional adaptive genetic algorithm’s easy "premature" shortcomings according to individual fitness of population. And a penalty function is used to handle constraints of assembly dimension chain. Finally, using the algorithm to optimize assembly chain tolerances of a gear reducer shaft, the effectiveness of the adaptive genetic algorithm to optimize tolerance allocation has been verified.

Single crystalline Mn3O4nanorods with diameters of 10-200 nm and lengths up to several microns have been synthesized by a simple hydrothermal method at a relatively low temperature. The products have been characterized by microscopic and spectroscopic techniques. From the Electron Spin Resonance (ESR) spectra of the products, hyperfine structure (six absorption peaks of ESR) of Mn2+ion adding the Mn3+ion signal was observed and results confirmed the nanorods showed paramagnetic behaviors.

Nanotubes, fabricated by mechanical bending of thin films, have been widely used in numerous fields. For a bilayer nanofilm, it could bend itself driven by effects of adsorption and ambient temperature. Therefore, in this work, we simulate the phenomenon of bilayer AuSi nanofilm bending into nanotube with the effects of surface stress induced by vdW interaction between adsorbed O or Hg atoms and atoms on Au surface and ambient temperature change by finite element emulation. The curves of nanotube calculated by finite element software accord with theoretical prediction results very well, that demonstrate our theoretical prediction formula has a great feasibility and efficiency in practical application.

An Ice-Detecting and Ice-Melting System of Electricity-Transmitting Lines based on ZigBee Wireless Communication uses ZigBee wireless network as the flat. Sub nodes are placed at some places of the electricity- transmitting lines. The sub nodes detect the icing status of electricity-transmitting lines by using the vibration tube ice sensors and send the ice signals to the main node via the ZigBee wireless network. The main node sends the ice signals to PC via USB interface and launches the ice-melting system at the same time. The principle and sense organ structure of the vibration tube ice sensor are briefly introduced. The hardware and software designs of sub node and main node are stress explained. Finally, the theory of the controllable inductor and capacitor compensation ice-melting system is particularly expatiated.

Particles concentration distribution in a stirred tank with pitched blade turbine was investigated using computational fluid dynamics. The effect of the pumping mode on the turbulent flow and particles concentration distribution was studied. The turbulent solid-liquid flow in a stirred tank was simulated using a two-fluid model with standard k-ε turbulence model. The multiple reference frames approach was used to simulate impeller rotation. Results show that different pumping modes create different flow field which decide the characteristics of the mixing quality. A further detailed discussion about particles mixing at the bottom of the stirred tank was made. The computational model and the predicted results discussed here would be useful for understanding the solid-liquid mixing process.

Reinforced concrete cover in the road culvert cover design, in order to facilitate the construction, usually using precast reinforced concrete solid slab, but the overall cost is not low. This article researched a reinforced concrete multi-ribbed hollow composite slab, it based on the theory of reinforced concrete multi-ribbed slab structures, using a precast reinforced concrete ribbed slab as the bottom die, then poured reinforced concrete beams and panels rib ,and them constituted a whole stack of reinforced concrete ribbed hollow slab. This kind of cover, compared with the precast reinforced concrete solid cover, is not only good mechanical properties, high integrity, but also saving concrete, steel, and bottom slab appeared smooth and fine, lower construction cost.

Mixing efficiency is an important parameter in the design of many industrial processes in stirred tanks. In this study, CFD technology was used to simulate the mixing process inside the stirred tank with dislocated blades and standard turbine. Calculations were performed to study the effects of agitator speed and the configuration of impellers on mixing efficiency. The results showed that the flow field in the stirred tank with the dislocated blades is better than the standard turbine, and the flow number of the dislocated blades had been improved while the power number had been reduced. According to calculation results of Wr, we found the mixing efficiency of the dislocated blades had been improved about 4 times than that of standard turbine.

Every Expo has constantly played a significant role in the exploration of us. Exploration here indicates a realizable dream rather than a pure Utopia. To describe this definition exactly, a new word “Ourtopia” is created, blending “Our” into “Topos” from ancient Greek, describing an attainable one through the transformation of the ideal into the real with a plurality of thought and action. Under this unique context, Shanghai Expo provides an opportunity to achieve Ourtopia from choosing of Expo sites, rebuilding of UBPA, reconstruction of industrial heritage itself. Through Shanghai Expo, industrial heritage succession is defined as a period of balancing different values, especially culture and economic. And, industrial heritage innovation between Pre-and-Post Expo must be based on analyzing these three comparisons---event-based VS. necessity, temporary VS. permanent, super-scale VS. comfortable-scale. Accordingly, other cities study from Shanghai Expo sample in terms of three perspectives--- Mega event VS. non-mega event, short periods VS. long-term impact, nationality VS. locality, thereby exploring industrial heritage potential value.

The 3D flow field generated by two-stage impellers in the agitation of xanthan gum, a pseudoplastic fluid with yield stress, was simulated using the commerical CFD package. The effect of impeller speed and impeller spacing on power number, cavern size and viscosity distribution was investigated in this work. The results showed that the power number was slightly influenced by impeller spacing. Higher impeller speed and larger impeller spacing contributed to creation of a bigger cavern. The range of high viscosity zone between the impellers increased with an increase in impeller spacing. Impeller speed and impeller spacing could be used as important parameters to improve the mixing performance of multi-stage impellers in the mixing of pseudoplastic fluids with yield stress.

Yarn tension controlling at heart is tuning servo-motor speed on a restricted range. In this paper, we proposed an advanced model predictive control strategy to solving filament winding system time-delay problem. The application of controlled auto-regressive integrated moving-average (CARIMA) model was described the dynamic time-varying character. The parameters of CARIMA model were solved by recursive least squares parameter estimation method through input-output data. And using the receding optimization method acquire controlling amount in the future. The result of simulation shows that the method is effective and the control structure is simple.

Arched section consisted of a rectangle and a semicircle part. It is commonly applied in the field of hydroelectric engineering. The normal water depth computation equation for an arched tunnel is a transcendental equation and no analytic solution. In this paper, based on the mathematics transformation for the basis equation and the relationship analysis between the dimensionless normal water depth and the relative parameters, a new linear solution formula are established for the calculation of normal water depth for arched section tunnel according to the fitting principle. This method overcomes the shortage of other iterative trial calculating methods, such as complex calculation step, depend on the special chart and curve, and existed serious error. The new formula is simply and the maximum error is less than 0.6156% under the general engineering design range (ratio of normal water depth and arch radius is between 1 to 1.5416). it can be used on the engineering designing practice and the edit of the handbook of hydraulic structure design.

BiOI nanolamellas and BiSI nanowires were synthesized using Bi(NO3)3·5H2O, (NH2)2CS and I2 as reactants in the solvothermal process with ethanol as the system media. The as-prepared samples were characterized by X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), Energy-Dispersive X-ray Spectrometer (EDS). The competitive growth of BiOI and BiSI were investigated by changing the quantity of (NH2)2CS. A possible reaction mechanism was proposed.

In the present work, detached eddy simulation (DES) of the turbulent flow in an unbaffled stirred tank agitated by a six-pitched-blade turbine was carried out. The sliding mesh (SM) approach was applied to simulate the rotation of the impeller. For comparison, the computations based on the large eddy simulation (LES) model and RANS equations closed with Reynolds stress model (RSM) were also performed. The instantaneous velocity fluctuations, mean velocity and turbulent kinetic energy profiles were analyzed and compared with the laser doppler velocimetry (LDV) results from literature. Results show that DES model can capture the unsteady turbulent flow characteristics accurately. The mean velocity and turbulent kinetic energy profiles by the DES model are in good agreements with the LES results and the LDV data. Besides, the computational cost of DES is only about 80% of LES. By contrast, the results obtained by RSM are not so good. It can be concluded that the DES model can produce as similarly good predictions as LES with less computational cost, and can work as an alternative of the LES model in predicting the hydrodynamics in the stirred tanks.

With the increasingly wide range applications of Web and the continue development of Web development technology, developers urgently need a framework to simplify the development process, reduce development effort and improve development efficiency. Rails is a Web framework which is more realistic and more efficient, it has the advantages of rapid development system of PHP and the advantages of structured programs of Java. So this paper analyzed the architecture of Rails framework in-depth, and designed an information system of auto leasehold management with the characteristics of Rails framework. The system realized unified and real-time management for the branches, the network traffic, orders and settlement data. The validity and efficiency of the system was validated via test-experiment. The results show that the system can enhance the standardized management of car rental, improve the management level and the information degree of the cars rental industry. At the same time, it can also increase the crackdown of car rental fraud, establish safe and effective prevention mechanisms, and reduce the loss of car rental.

2-((5-mercapto-1, 3, 4 -oxadiazol-2-yl) methyl) benzo[d]isothiazol-3(2H)-one was synthesized and characterized by means of IR, 1H NMR, MS. The compound was tested preliminarily against the bacteria including Escherichia coli, Staphyloccus aurueus, Vibrio alginolyticus, Aeromonas hydrophila and Bacillus subtilis. The results show the title compound has good antimicrobial activity. Isothiazol-3(2H)-ones, 1,2-benzisothiazol-3(2H)-ones, and their heterocyclic bioisomeric derivatives are potent industrial microbiocides with antifungal and antibacterial activities[1,2], highly potent platelet aggregation inhibitor[3], anti-inflammatory, analgedic and anti-pyretic activities[4]. And the biocide 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one is a nonmetallic and nonenvironmentally persistent biocide, which has been registered in several countries as an antifouling agent and has gained approval in the USA and Environmental Protection Agency[5]. Isothiazolones represent a class of versatile intermediates in the synthesis of heterocyclic compounds [6]. According to above facts and the principle of combination of bioactive sub-structure, we herein designed and synthesized benzisothiazolone derivatives2-((5-mercapto-1, 3, 4 -oxadiazol-2-yl) methyl) benzo[d] isothiazol -3(2H)-one, as shown in Scheme 1.

A novel α-alumina-g-polyvinylpyrrolidone (α-Al2O3-g-PVP) composite abrasive was prepared by surface grafting polymerization. The chemical mechanical polishing (CMP) performances of the composite abrasive on hard disk substrate were investigated with a UNIPOL-1502 polishing machine. Analyses on the surface of polished substrate indicated that the α-Al2O3-g-PVP composite abrasive exhibited lower surface roughness, less scratch, and improved post-CMP cleaning performances than pure α-alumina abrasive under the same testing conditions.

The superhydrophobic and highly oleophobic cotton textile was obtained by applying particle -based in situ fabrication procedure with the low toxic perfluoropolyether (PFPE) and the silica particles. The water contact angle and salad oil contact angle on the treated cotton textile surface can be achieved to 156.8 º and 143.3 º respectively. The microstructure of the treated cotton textile surface was revealed by scanning electron microscopy (SEM). And the chemical composition of the treated cotton textile surface was determined by the X-ray photoelectron spectroscopy (XPS) analysis. Thermogravimetric (TG) analysis showed that the weight loss of the treated cotton is less than that of the untreated sample.