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In order to study the influence of different types of weld defects, such as slag inclusion, porosity, incomplete fusion, incomplete fusion, burn through, crack on the mechanical performance of X65 marine pipe welding joint (Φ323.9 x 16 mm), the test on the mechanical properties of static tensile, fracture toughness CTOD and fatigue life were carried out to achieve the maximal defect tolerance size allowed in this paper. Research shows that the existence of crack defects would significantly reduce the fracture strength and the fatigue life of welded joint, the application of the maximal defect tolerance size allowed based on crack defects assessment can provide referential basis for the safe and stable operation of marine pipelines.

To overcome the defect that the support pressure is required to be measured or supposed in elasto-plastic analysis in strain-softening rock mass, by the connection of the support pressure imposed on surrounding rock mass, without assuming the support pressure is known a priori, an improved model of solving plastic radius and the distribution of radial displacement around the circular tunnel is proposed. Based on Hoek-Brown yield criterion, the results obtained by strain-softening model are compared with those of elastic perfectly brittle and elastic perfectly plastic models. The examples reveal that the difference of plastic radius obtained by the three models is comparatively smaller, but the difference of radial displacement is comparatively larger. The proposed model overcomes some defects of the previous studies in deformation analysis for tunnel.

We always use projection transformation to display and draw 3D object. With the aid of matrix transformation algorithm, this paper deduces projection transformation matrix of 3D object’s three views, gets these points’planar coordinate, then we can present the three views. It has practical application value.

This article presents the progress on characterization of the interfacial interaction between sulfur oxidizing microbes and sulfide minerals by using of synchrotron radiation-based techniques including S/Fe/Cu X-ray absorption near-edge structure spectroscopy (XANES), X-ray Diffraction (XRD), micro-X-ray fluorescence (μ-XRF) mapping and micro-scanning transmission X-ray microscopy (μ-STXM) imaging, together with other accessory approaches such as SEM/EDS, Raman spectroscopy, FT-IR spectroscopy, and electrochemical methods as well as comparative proteomics methodology.

The in situ relevance of micro- structure and electrochemical properties of chalcopyrite to adsorption of thermoacidophilic bioleaching Archaea Acidianus manzaensis was studied. In this study, the electrochemical behavior of chalcopyrite was first investigated by cyclic voltammetry (CV) to get suitable initial reduction and oxidation potentials, at which electrochemical corrosions of chalcopyrite for several time were performed, respectively, to get specific surface micro-structures. The specific adsorption of A. manzaensis on the electrochemically corroded chalcopyrite surface was then comparatively studied. The changes of microstructure and chemical composition/speciation on the surface of chalcopyrite before and after electrochemical treatment and bio-adsorption was characterized by scanning electron microscopy/electron dispersive spectroscopy (SEM/EDS), and synchrotron radiation-based X-ray diffraction (SR-XRD) and Fe, Cu K-edge X-ray absorption near edge structure (XANES) spectroscopy. The results showed that the suitable initial oxidation and reduction of chalcopyrite electrode were at 0.67 V for 1h and -0.54 V for 10 min, respectively. After treated at 0.67V the surface of chalcopyrite became Cu-deficient with a composition of CuFe1.02S2.15, and bornite (Cu5FeS4) was detected. While after treated at -0.54V, the surface became Fe/S-deficient, with a composition of CuFe0.33S0.81, and a mass of chalcocite and some covellite were detected. Comparing to the original chalcopyrite, the adsorption capacity of A. manzaensis was increased on the surface of oxidation-treatment at 0.67 V, and decreased on the surface of reduction-treatment at -0.54 V. It clearly demonstrates the bornite-containing copper deficient chalcopyrite surface was more preferably adsorbed, whereas the chalcocite-containing Fe/S deficient chalcopyrite surface was less adsorbed by A. manzaensis, indicating the dependence of the specific adsorption of A. manzaensis upon the secondary minerals as well as Fe/S availability in the microstructure of chalcopyrite.

LGJ150/25 steel core aluminum stranded wires were selected as the test wires, and the aeolian vibrations which work in different cycle times of wire that is under the conditions of dry and acidic corrosion were simulated by the self-made test bed. The electronic number of corona discharge of each pre-set conductor was measured, when applying AC high voltage on the wearing wires step by step,so that the corona inception voltages of the conductors could be confirmed. And the effect of the vibration cycle times and environmental conditions on the corona discharge was researched. Taking the sum of all aluminium stands wear area of a pre-set wire as the fretting wearing capacity, the relationship between the wire wearing capacity and the corona discharge was studied. The results indicate that the corona inception voltages of the conductors decrease with the increase of the cycle times and the wires wear capacity. In general, the wear capacity of the acidic corrosion conductors is larger, and its corona inception voltage is lower. Therefore the decrease of the conductor fretting wear can effectively reduce the corona loss of transmission lines and other hazards.

Gas hydrates are a major concern in oil and gas industry, Gas hydrates form in small amounts of water, gas, and the appropriate pressure and temperature conditions. Gas hydrate storage and transportation technology starts a new way for energy storage and transportation industry. The most critically technical problem is how to improve the hydrate formation rate, storage capacity and form continuously. The influences of surfactants on induction time in three types of solution with equal concentration were studied by means of visual hydrate experimental equipment, and generalized induction time was measured by direct observation method. Specific effects of different surfactants on hydrate formation were summarized, as well as the hydrate formation mechanism of surfactants . The lack of research and the research direction of the future were concluded . The further study of surfactant mechanism and build kinetics model containing surfactant have important theoretical value . The result shows that the gas molecules saturated due to the solubilization of surfactant, which promotes the progress of mass transfer in the hydrates. And driving force is provided for the complexation of host molecules and guest molecules during the formation progress of gas hydrates.

In this paper, based on triethanolamine on application effect of reactive dyes, the design of a new kind of dyeing assistant NN '- three the two amine ether, through the experiment, verify the dyeing assistant and good effect of reactive dyes with good fiber in dyeing process, has practical significance of application of reactive dyes.

AlF3 and MgF2 were applied to modify the surface of the LiNi1/3Co1/3Mn1/3O2 cathode material. The structural and electrochemical properties of the materials were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), charge–discharge tests and electrochemical impedance spectra (EIS). The results show that the 1 wt.% AlF3 and 1 wt.% MgF2 coated LiNi1/3Co1/3Mn1/3O2 (NCM333) cathode material exhibits an optimized electrochemical performance. It presents an initial capacity of 207.2mAh/g and 169.1mAh/g at 0.2C between 2.8V and 4.7V after charge-discharge 65 cycles. The rate performance is also enhanced because the coating decreases the interface charge transfer impedance.

Brine corrosion can remain a large obstacle to the rehabilitation project of Missan Oilfields in Iraq. To minimizecorrosion risks, the 13-3/8′′ casing steel, N80,has been employed to examine corrosion behaviors in simulated formation water (i.e., brine). The impact factors of corrosion such as temperature, ion contents, exposure time, and pH have been studied. Also, corrosion inhibitors available in brine have been screened by a static weight loss method. The results showed that effects of environmental and operational variables on N80 corrosion are fairly complicated; the corrosion inhibitor, HN-amph, exhibits excellent corrosion inhibition in brine. This work will provide important information for on-site application.

This paper introduces the "5.20" of the emulsion explosive incident and analysis the cause of the accident. Based on the production of explosion accident summarizes the security problems of emulsion explosive production process, and relevant measures are put forward. Combining the decomposition mechanism of ammonium nitrate in the emulsion explosives and the lessons from the production of emulsion explosives explosion, the conditions of the emulsion explosives (matrix) thermal decomposition in the emulsifier are given that are the formation of hot spot and the accumulation of heat. Then the factors of hot spots generated in the production of emulsion explosives and the occurred conditions of the heat accumulation are analyzed and summarized.

Chemical reaction rate of SiC wafer surface usually determines the material removal rate (MRR) in chemical mechanical polishing (CMP). In this paper, systemic experiments are carried out to discover the relationship between Fe catalyst with different forms or valence and chemical reaction rate based on Fenton reaction. Experimental results show that the MRR changes little using Fe powder or hydrogen peroxide (H2O2) alone, but the MRR of SiC will increase largely by adding them both that will produce Fenton reaction. The MRR continues to increase slightly when Fe2+ ions is employ as catalyst, but that is much lower when utilizing Fe3+ ions. Moreover, SiC wafer with a smaller surface roughness and better quality can be obtained when using Fe powder as catalyst in Fenton reaction. The results indicate that the Fenton reaction can effectively improve the polishing efficiency of SiC substrate and Fe powder is more suitable for polishing of SiC than ferrous or ferric salt in CMP based on Fenton reaction.

Rare earth oxides co-doped zirconia has been developed for application in thermal barrier coating (TBC) systems to promote the performance and durability. In this paper, the phase stability and thermal physical properties of 1mol.%La2O3, 4.5mol.%Y2O3stabilized ZrO2(LaYSZ) were investigated. After 100 h heat treated at 1400°C, the content of monoclinic phase in LaYSZ was 2.32 mol%, which is lower than that in YSZ (46.9 mol%). Result indicates that the LaYSZ has better phase stability and lower thermal conductivity than YSZ. The LaYSZ system can be explored as the candidate material as ceramic layer in TBC.

The tensile mechanical properties of polyethylene/silica (PE/SiO2) composite fiber and three-strand PE/SiO2composite fiber ropes were investigated. It was found that the SiO2content had a significant effect on the tensile mechanical properties of composite fiber. The breaking force of the fishing three-strand PE/SiO2composite fiber rope with diameter 8 mm was 15.8 kN. Compared to common synthetic fiber rope with the same diameter, fishing three-strand PE/SiO2composite fiber rope had higher breaking force and less elongation. On the premise of maintain the breaking force, the common synthetic fiber rope could be replaced by the fishing three-strand PE/SiO2composite fiber rope in fishing area, and the linear density, the elongation at break, the netting gear resistance and using diameter of rope decreased. Therefore, an efficient method to improve the tensile mechanical properties and lower cost by using composite fiber rope was established.

Polystyrene (PS) had wide range of applications in food packaging field. Mechanical recycling of PS was simulated by multiple extrusions to assess the behavior of physical degradation. The molecular weight and the molecular weight distribution of PS with different extrusion cycles were investigated by gel permeation chromatography (GPC). Experimental results show that the differential and cumulative distribution curves of PS shift to smaller values with the number of extrusions cycled increasing. The Mn and Mw of PS decrease. However, Polydispersity index (PDI) increases obviously.

The fatigue properties of refill friction stir welding joints of 6082-T6 aluminum alloy were completed based on the optimal process parameters. The expression of the fatigue life prediction were obtained in a certain range. The microstructure and fatigue fracture appearance of welding joints were observed and analyzed. And the microhardness of the joints were tested. The results showed that the fatigue crack initiated from the root of the joints between the lower and upper plate, that is the junction of HAZ and TMAZ, and then propagated to fracture along the boundary between the HAZ and the TMAZ. Strengthening phase which was formed of trace elements significantly affected the fatigue properties of spot welding joints. The fatigue life of spot welding joints along with stress intensity factors decrease showed an increasing trend. Fatigue life of spot welding joints emerge an increasing trend along with decreases of the load.

This study proposes a novel auditory brain–computer interface (BCI) based on dichotic listening paradigm, which allows the subject to select a target from two different sound stimulus sequences played in each ear. EEG data from 6 subjects has shown that the amplitude of N200 and P300 elicited by target was significantly higher than that of non-target ones. We found the N2ac component: a negativity wave in the N2 latency range at anterior contralateral electrodes. The target detection accuracy was assessed by support vector machine (SVM). The accuracy based on multiple electrodes is higher than a single electrode. The dichotic listening paradigm can be used for binary-class of brain-computer interface system.

Based on "indentation fracture mechanics" model, this paper offers a model on the crack depth of surface in ceramics grinding. Through carrying out one-way trip grinding and surface crack depth measuring experiments on silicon nitride, a model for silicon nitride grinding surface crack depth is established. In this model, the parameters can be confirmed by the experiment. By the grinding experiment, the parameters of the model can be confirmed, and the controlled grinding surface quality for the ceramic materials can be expected.

This paper uses the simulation software VISSIM to build temporary parking traffic models in front of the Affiliated Primary School of the Inner Mongolia Agricultural University. Selecting speed, acceleration and queued data calibrate the simulation model. The results prove that the simulation model is effective. After that two organizations plan are proposed to ease congestion.

Heat self-generated CO2 technique is proposed, which is focused on the problems of recovery difficulty, poor effect steam soaking and so on for heavy oil reservoirs. This technology is combining of steam flooding and gas flooding and so on. Its main mechanism is the application of steam heating blowing agent to generate a large volume of gases (including CO2, NH3, etc) in the formation. While some of these gases acting with the oil to reduce the oil viscosity, some form miscible flooding to reduce water interfacial tension, so as to achieve the purpose of enhancing oil recovery. An optimized selection of the heat blowing agents was performed. By comparison the difference before and after the reaction of blowing agent solution, the increase of alkaline is occurred after the reaction, and is helpful to reduce oil viscosity and lower interfacial tension, etc. Studies indicate that heat-generating CO2 flooding technology can get a maximum viscosity reduction rate of 76.7%, oil-water interfacial tension decreased by 54.77%, further improve oil recovery by 4.17% based on the steam drive, which shows a technical advantage toward conventional EOR method. The field experiments indicate that the technique can greatly improve the oil production, which will provide a powerful technical supporting for the efficient development of heavy oil.

Fabrication of superhydrophobic structure by femtosecond laser become more and more popular in recent years, because it’s inexpensive and micro/nanostructure can be controlled compared with other methods. This paper proposes an approach to fabricate large scale superhydrophobic structure directly on nickel (Ni) surface by femtosecond laser and the apparent contact angle (CA) on the Ni surface can reach 134° without further coating any low surface energy materials. With low laser power, typical laser-induced periodic surface structures (LIPSS) at the submicron level can be observed. With high laser power, periodic ripples with microstructure covered by LIPSS can be observed. The micro/nanostructure on Ni surface is directly replicated onto PDMS and after replication the CA on PDMS surface can be improved to 153° obviously from CA of 120° on PDMS surface without micro/nanostructure. The higher laser power can results in the larger CA. This replication method can be applied for fabricating large scale superhydrophobic structure and the replication master can be used many times.

A novel aminotriacetic acid (NTA) intercalated MgAl-LDHs have been successfully synthesized by anion exchange method with MgAl-NO3-LDHs as precursor. The XRD pattern implies that NTA anions have replaced NO3- in the interlayer of LDHs. The FT-IR spectra also indicates that NTA anions have intercalated into layers’ space of LDHs, and the carboxyl groups of NTA have been converted into carboxyl anions after intercalation process. When comparing IR spectra of MgAl-NTA-LDHs and MgAl-CO3-LDHs, higher and stronger absorption was observed in the range of 1428-1250 cm-1, especially in the range of 1111-909 cm-1.

Modeling and finite element analysis functions were combined in Solid Edge to optimize gear parameters. Gear parameters optimization objective and procedure in different conditions were summed up. A complete Excel file was created. An involute gear parametric model was established which was interlinking with the Excel file. And the model’s accuracy would not alter with the diameter’s change. The wizard software for gear drive design and parameter optimization was developed on platform of Solid Edge by Visual Basic tool. This application can guide users getting the initial parameters and optimizing the parameters by the circling method of diminishing parameters, analyzing the precise gear root stress with Femap Express module, and diminishing them again. Users can get a gear model which has a smaller diameter and smaller module and satisfies strength demands.

This paper analyzes three main factors (turbulence intensity, air density, annual average wind speed ) that influence the low wind speed wind turbine fatigue loads, In order to analyze the influence of each main parameters how to affect the fatigue load of low wind speed wind turbine, using a 2000kW wind turbine as an example on the simulation test , 3 turbulence, 4 air density and 7 annual average wind speed were employed. The results show that, with the air density, turbulence intensity and the annual average wind speed increases, the wind turbine of fatigue load increase in rule approximately. Based on the above rule, it can reduce fatigue loads and prolong the life of wind turbine in design optimization of low wind speed wind turbine and sit choice.

Through the market investigation was designed based on the environmental monitoring system, intelligent control system and simulation system of security system, intelligent Home Furnishing system, this system uses CC2530 and sensors to build a ZigBee network, and realizes the remote monitoring through GPRS module, configuration of the PC software for the system, realized the function of intelligent furniture system through the actual test, that, the system is stable and reliable, practical.

In order to research the resistance characteristic of silicon-based composite tiles under high temperature thermal load on aircraft during its reentry into the earth's atmosphere, the ordinary resistance measurements were comparatively discussed according to the operational environment of composite, two parallel electrodes probe test method was proposed, and the resistance test platform under high temperature thermal load was developed, by which the resistance characteristic of silicon-based composite tiles was continuous monitored under different thermal load. The result shows that: If the temperature is not higher than 600°C, the resistance will increase with the decrease of temperature until it reached the resistance value at room temperature; If the temperature is higher than 700°C, the resistance characteristic will be changed everlastingly; If the temperature is higher than 800°C, the resistance will be less than 1kΩ and will not change any more.

In order to greenhouse plants for automatic irrigation operation, was designed based on the soil moisture monitoring system of RS 485 bus system, the oscillation frequency of the clock oscillation circuit, and a main chip count, frequency signal PC software will be the main chip records show, form curve, thus providing the basis of the data for the automatic irrigation, experimentally tested for a long time, the system performance is stable and reliable.

The concentrations of essential trace elements such as Mn, Cu, Zn, Fe, Li and Se were determined in pomegranate juice at distinct maturity stages by ICP-MS following microwave-assisted acid digestion. The digestion efficiency was evaluated on the basis of the determination of residual carbon content and residual acidity. 4 mL of 16 mol/L HNO3 + 2 mL of 30% m/m H2O2 solutions were used for the efficient digestion of 3.0 mL pomegranate juice, with a considerable reduction in the residual acidity when compared with a procedure that employed different Digestion procedures. The good agreement between the observed and certified concentrations of the National Tea Standard (China, GBW10016) and the Apple Standard (China, GBW10019) indicate that the developed analytical method was well suited to determine the trace elements contents in similar matrices.

A novel building block in organic synthesis, poly (4-iodobutoxylmethylsiloxane)(PIBMS) with high reaction activity was prepared by poly (hydromethylsiloxane)(PHMS), methyl iodide and tetrahydrofuran (THF) in the presence of a catalytic amount of PdCl2. The structure of PIBMS was characterized by the FT-IR and NMR spectra. The reaction conditions were optimized.

By means of self-emulsifying, blocked & crosslinked cationic polyurethane (CBPU) microemulsion was prepared with isophorone diisocyanate (IPDI), polycaprolactone glycol, bisphenol A, methyldiethanolamine (MDEA) as cationic hydrophilic chain-extending agent, ̴̵̹̹̱̼̽͊̿˰̱̓˰̷̲̼̳̻̹̿̾˰̷̵̱̾̈́˰̴̱̾˰̞˽̫˸́˼́˽̴̵̸̹͉̼̽̈́˽̂˽̵̱̳͉̼̈́˹̵̸͉̼̭̈́˽ڂ˽̴̸̴̵̸̹͉͈͉͉̼̱̹͂̿̈́̽̾̿˰̴̵̱̱̹̀͂̿̀̾̽˸̠̔̔˹˰̱̓˰̷̳̼̹̻̹͂̿̓̓̾̾˰̷̵̱̾̈́˾˰̶̶̵̳̈́̓̕˰̶̿˰̸̵̈́˰̠̥̓̒˰̵̴̲̼̳̻̿˰̱̹͂̈́̿˰̿̾˰̸̵̈́˰̸͉̹̳̱̼̀̓˰̵̵̹̀͂̿̀͂̈́̓˰̶̿˰̸̵̈́˰̵̵̴̱̈́͂̈́˰̵̱̀̀͂˰̵̵͇͂˰̴̵̴̹̓̈́ͅ˾˰̸̵̤˰̵̵̵͈̹̱̼̀͂̽̾̈́˰̵̼͂̓̈́̓ͅ˰̸͇̓̿˰̓̈́͂uctures of tertiary amine group, imidazole ring and urethane group are found in CBPU molecular structure. The morphology of the particle is uniform spheric structure and its size is related to the content of tertiary amine groups of CBPU. The paper strength, especially the wet strength can be obviously increased with the increasing of the blocked ratio of CBPU. The optimum blocked ratio of CBPU is 10%.

Novel nanobranched Ni/Fe-LDHs were successfully prepared by coprecipitation method without adhesive condition. The effects of different factors as pH and aging time on its morphology were discussed in detail. According to the results, the branches diameters of Ni/Fe-LDHs are among 50-100nm and the optimum experiment pH equals 10 and experiment time is 48 hours. Therefore, the nanobranched Ni/Fe-LDHs can be expected to be potential for designing and investigating novel materials.

Catalytic converter is an important device of automobile engine exhaust system. Based on Hydromechanics, the relational mathematical models of catalytic converter simulation are established and the parameters are calculated. Making use of CFD numerical simulation method, a simulation is set up for the internal flow field of catalytic converter original model using fluent software. From the simulation, the internal flow characteristic is understood. On the basis of this, through the optimization idea adding a guiding device in inlet cone of catalytic converter, the uniformity of velocity of flow is improved. The simulation analysis show that the flow uniformity for internal flow field can be improved observably in the structural optimization, the increasing degree of pressure loss is with little range. A new idea and reference may be offered for improving flow uniformity of a catalytic converter.

The purpose of this study is to investigate the catalytic effects of different metals in Shengli lignite on the char reactivity. The pyrolysis of Shengli lignite and various metal catalyst loaded coal was investigated in a small fixed-bed reactor, and the gasification activity with steam for different chars was compared as well. The results show that Fe, Ni, Ca and K could effectively lowering the gasification temperature, enhancing the gasification reactivity of SL char. Alkali (K) and alkaline earth (Ca) could be feasibly used as catalysis for the catalytic steam gasification at relatively low temperatures (550~700°C) to produce gases with high H2 (63.2~63.8 v%) and low CO (below 0.9%), and promoting the carbon-water reaction, the water-gas shift reaction to some extent.

A flume experiment is carried out to explore regular waves shoaling and breaking in surf zone. The topography is two-slope model, which is composed of a steep slope 1:5 and a gentle slope 1:40. The incidence waves have heights of 0.05, 0.06, 0.07, 0.08, 0.09 and 0.10 m, and periods of 1.0 sec. In order to describe the wave propagation in surf zone, wave height is collected by wave gauges and wave breaking is recorded by high-speed camera. The results show that, when incidence height is increased, the breaking height increases, while the location of breaking point moves forward. When the incidence height is larger enough, the trend slow down. Besides, secondary breakup is observed in case 0.08, 0.09 and 0.10m. The transient period from primary breakup to secondary breakup is a very important phase. Computing and forecasting methods of surf with complicated topography need further study.

Multimedia technology in the field of education and teaching has made great achievements. It is also used widely in the area of sport. However, multimedia technology in the teaching of basketball tactics is still in the initial stage. The paper is to study the application of multimedia technology in teaching basketball tactics, and to make "basic tactics of basketball teaching" Multimedia CAI Courseware. The Study shows that it is possible to use multimedia technology in basketball tactics, and it is bound to help improve basic tactics of basketball teaching.

The quantum chemistry is a kind of efficient theoretical research methodology; it has become an important foundation and core technology to the computational materials science. The researches of melting mechanism, doping mechanism, mechanism of hydration activity can be used in the related areas of stabilization of heavy metal by cement. Density functional theory is reviewed in the study of the affective mechanism of cement hydration activity and the intensity of hydration by heavy metal, the mechanism of fixating heavy metals by mineral and the mechanism of lowering melting temperature. It is considered that quantum chemistry can be used to make a simulation at the micro level to explore the mechanism of cement-enclosed heavy metals and has a perfect theoretical guiding significance for further research.

The investigation about traveling wave solutions of nonlinear equations is an important and interesting subject because they play important role in understanding the nonlinear problems. By using the (G′/G)-expansion method proposed recently, we construct the travelling wave solutions involving parameters for the Hirota and Satsuma equations. The travelling wave solutions are expressed by the hyperbolic functions, the trigonometric functions and the rational functions. The numerical simulation figures are shown.

In this work, the interface reaction between Al2O3 ceramic and Ag70.5Cu27.5Ti2 brazing filler metal at 845-860°C was investigated. Based on the data of thermodynamics and kinetics, the Gibbs free energies of the main interface reactions in the real brazing system condition were calculated. But the values of normal equilibrium reaction condition and the real interface reaction brazing system were different; and the main influential factor was the brazing temperature, and the system vacuum of brazing condition can lead the change of equilibrium constant (Kα). The results revealed that the high temperature and vacuum active brazing is a non-equilibrium interface reaction especially to titanium alloy, the vacuum and alloy liquid solution are beneficial to the brazing process, and the by-product formation of titanium-oxygen are affected by the diffusion process.

Radius filler is a kind of filling material which is used in triangle gap of the composite girder and rib. To optimize the hand-made craft of radius fillers and specify the evaluative requirements for detecting radius fillers, a research on handcraft parameters of the radius fillers had been conducted; the boundary dimension, microstructure and mechanical property of the R6 radius fillers had been characterized with the use of different detective methods and the microanalysis includes: nondestructive testing; microscope photos; fiber volume fraction and void content. The evaluative requirements to detect the quality of radius fillers have been established and its validity has been confirmed by the R8 radius fillers.

The research has identified turbulence intensity, annual wind speed and air density as the three basics of fatigue loads, in this paper, we call it three basics for short. This paper presents a method to analyze the three basics of the wind turbine fatigue loads. It explains the fatigue loads analysis idea and method of the three basics and it use the analysis method to research the extent of the influence by using a 1650kW wind turbine as an example. It can be seen from the results that the wind resources increase one classification, the influence of the turbulence intensity is the greatest, then the annual wind speed, finally the air density.

The traveling wave solutions to the heigher order Korteweg-de Vries equation is obtained by using Riccati equation. The method is straightforward and concise, the applications are promising to obtain traveling wave solutions of various partial differential equations. It is shown that the Riccati equation method, with the symbolic computation, provide an effective and powerful mathematical tools for solving such systems. The numerical simulation of the solutions are given for completeness.

Hotels have offered a large number of employment opportunities for society as one of rapid development industries in our country. Whereas hotels face threat from the high loss rate of personnel' demission that even exceeds expected numerical value,as a result,loss directly influences the sustainable development of enterprises. This paper describes the status and characteristic of loss of hotels employees according to the investigation datum of personnel' demission interview in one hotel of Shenzhen,and dissects the main reason why employees leave their posts by adopting Maslow’s demand level theory.

Based on the equivalent radius model and superposition potential, a productivity model for ultra-low permeability tight gas reservoirs was developed, which considered the influence of the threshold pressure gradient and the variable mass flow in fractures, and pressure loss inside the wellbore. With examples for capacity sensitive factors are analyzed. The results show that the threshold pressure gradient must be accounted to evaluate the productivity in ultra-low permeability tight gas reservoirs; after considering wellbore pressure loss; close toe fractures inflow velocity segment has been reduced; the larger matrix permeability, the greater the optimum fracture conductivity; When the number of fracture is more, the greater the impact on the capacity of the fracture angle. The research results provide a scientific basis for the design of multi-fractured horizontal wells in the ultra-low permeability tight gas reservoirs.

The once-through boiler is widely used in high capacity unit currently, however its heat storage capacity is small, and the unit’s response lags during primary frequency regulation. These all lead to the limited frequency regulation ability. For the purpose of studying the primary frequency regulation optimized control strategy, this paper established a primary frequency regulation characteristic simulation platform based on stimulative simulation system. Using this platform, it proposed an improved program for once-through boiler’s primary frequency regulation control strategy. It’s supposed to cover the insufficient heat storage capacity of the boiler by introducing the differential feed forward signal of the fuel supply and water flow. The simulation result shows that the proposed control scheme effectively improves the speed of primary frequency regulation. This platform provides a reliable basis for once-through boiler’s primary frequency regulation control strategy, and also has a certain guiding significance for further study.

The alterations of the water level in the middle reaches of Yangtze River were investigated using the range of variability approach based on daily water level datasets extracted from 5hydrological stations.Results show that the operation of the Three Gorges Dam disturbed the hydrologic regime downstream and directly affected the water level to some extent. The rate and frequency of water level changes was most altered, while the timing of annual extreme water level was least affected. For the overall degrees of hydrologic alteration, high degrees were identified in Yichang (56%) and Jianli (47%) reaches; moderate degrees in Hankou (45%) reaches; and low degrees in Chenglingji (37%) and Luoshan (40%) reaches. Water level alterations in the middle reaches of Yangtze River were mainly caused by human activitiessuch as dam construction in the upstream and in-channel sand dredging, and also natural hydrological processes.

There is a serious security problem in the process of workpieces flipping, which restricts the increase of production capacity in manufacturing process of large workpieces applied in nuclear power equipment. The shapes and characteristics of flipping workpieces were analyzed; the general model of workpieces outer contour was established. The design goals of heavy castings and forgings cold-work turnover mechanism were formulated based on the requirements of turning process, then the basic constraint-face was build and the geometric constraint-model was uniformed. A novelty 3- DOF planar serial mechanism of heavy upender was proposed whose overall configuration consists of three movements, that is roll, mobile, folding turn, which can realize the double function of turning 90 ° and 180 ° of large workpiece as hollow cylindrical, conical and spherical crown three types. On this basis, the airbags-drived flipping worktable was designed; Topological optimization of flipping worktable was further conducted. Its key technology will provide useful ideas and references for the development of large heavy duty positioner and turnover machine with its other related equipment.

Controlled Permeable Formwork Lining (CPFL) has particular water-storaging capacity, the mixing water remained in the CPFL can provide moisture curing for the surface layer concrete for a period time. In this paper, the water storage was tested, the appearance quality, rebound hardness and durability of the surface concrete were studied. Results shown that CPFL can significantly improved the appearance quality, early age rebound hardness, carbonation resistance, chloride ion penetration resistance and freezing-thawing resistance of the surface concrete; the coating age of anti-corrosion coating was shortened to 18 days, the cofferdam turnover rate was speeded up, the engineering cost was reduced; the coating adhesion was significantly improved and the thickness of dry coating film and adhesion of discrete were reduced. The benefit of using CPFL technology is remarkable, and it is worth promoting.

Fatigue crack propagation behaviors coupled with the microstructure evolution of a hardworking Ni-based superalloy after long-time aging at 1023K were studied, to provide fundamental data for the fatigue life prediction of the superalloy. The results show that the microstructures remarkably change and the fatigue crack propagation resistance decreases with the aging time prolongs. It is found that the precipitation and the growth of topologically close packed (TCP) phases as well as the coarsening of γ' phase and carbides on grain boundaries can significantly affect the fatigue crack growth rate. On one hand, coarsened γ' phase and carbides at grain boundaries block dislocation movements near the crack tip, thus the fatigue crack propagation is hindered in near-threshold region and Paris region. On the other hand, the stress concentration accumulates continually with carbides precipitation increases, so that the grain boundaries become the main fatigue crack propagation rout. As well as, the effect of the TCP phases on the fatigue crack propagation behavior ascribes to the size and the distribution of TCP phases. Very small quantity of TCP phases contribute to pinning dislocation and enlarging fatigue crack propagation absorption energy, but high quantity of TCP phases with short rod shape changed to the needle, which gradually precipitate uniformly within the grain after 1000h besides on grain boundaries in the earlier aging, leads to much higher stress concentration degree. Those discussed above are the most important reasons why the fatigue crack growth rate increases after long-time aging.

2 × 660MW ultra-supercritical units of O'Brien Power Plant are single configuration of auxiliary pilot project, due to the higher its parameters and performance requirements, it need better control strategies to ensure safe and economical operation. Against traditional cascade PID main steam’s temperature control system delaying large, this article proposed control strategy based on Smith estimated. Main steam’s temperature controlled object inert zone mathematical model can be showed by multi-volume model, and use the improved system for large inertia Smith Predictor to make dynamic parameter control systems improvements. Simulation results of the simulation machine show that: Optimization emperor steam temperature control is in an adjustable range and the policy in separate auxiliary units is feasible.

According to the characteristic of polyhydroxy alcohol fracturing fluid system, the regeneration of the system was investigated for the first time. A stable organic boron crosslinking poly (vinyl alcohol) regenerable polyhydroxy alcohol fracturing fluid system was prepared, and the rheological property of the polyhydroxy alcohol fracturing fluid system with different regenerable times was also researched. The effect of regenerable times on the rheological property of the system was studied. The results indicated that the aims of gel breaking and regeneration can be achieved by regulating its pH value and controlling its crosslinking degree. With the increment of the regenerable time, both the temperature resistance and shearing resistance performances were decreased, and the viscoelasticity of the gel was also reduced.