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A simple fluorescent iodide ion sensor was fabricated. Ag+ was found to specifically induce the aggregation of perylene–3, 4, 9, 10–tetracarboxylate tetrapotassium salt (PTK) in water, simultaneously, fluorescence of PTK was quenched. The resultant PTK–Ag+ aggregates showed a "turn–on" fluorescence response for halide ion, especially I-, and excellent selectivity toward possible interfering anions, contain sulfide.

shantytown renovation is a significant livelihood project. So far, 9 years have passed since the launching of a national large-scaled shantytown renovation and certain experiences and lessons have been learnt. This paper has studied shantytown renovation project from theoretical perspective while combining with reality; meanwhile, this paper has narrowed down the scope of study by focusing on typical shantytown renovations in industrial and mining cities as representatives; finally, systematic and scientific research methods are applied to study landscape renovation and regeneration of shantytowns in the industrial and mining cities. Furthermore, experiences and laws are concluded by taking the shantytown renovation project of Tongling city (an ancient copper city in China) in Anhui province as an example so as to provide a new idea or direction for carrying out shantytown renovation activities in industrial and mining cities under the background of new-type urbanization.

Pineapple is widely planted as one of the four major crops in in south China. The handling of residual pineapple leaves is not a step for looking down upon after harvesting. So far, returning the residual on the filed is the popular method, compared to set the residual on fire, crushing and returning has distinct advantage on high-efficient and low-pollution. In the text, the technology and machine of crushing and returning is summarized, and the current problems is analyzed and discussed.

Through on-site inspection for the typical coal mines of each coal tectonic units in Southwest Guizhou as well as analysis of gas parameter, highlight information and gas control technology, the thesis makes the following conclusions. Namely, the overall state of coal seam gas occurrence in Southwest Guizhou mining area presents characteristics with high degree in north and west together with low degree in east. With regard to the existing problems in gas control of this region, it has put forward some suggestions. For example, people shall add test parameters for coal seam gas in most mines, find out status of the mine gas occurrence, make specialized design in terms of gas emission characteristics and perform strict management to ensure proper implementation. Moreover, people can carry out targeted research for outburst prevention indicator, establish suitable predictor system, optimize instrument and equipment, match with current advanced production technology, introduce professional talents and strengthen training for related technology and management personnel.

This study tests the antimicrobial properties of pineapple leaf fiber. Scanning electron microscopy (SEM), infrared analysis (IR) and other test methods were used to examine the microcosmic morphologies of pineapple leaf fiber. As the pineapple leaf fiber adhesive content reduce fiber antibacterial. Adhesive content 54% of fiber to escherichia coli and staphylococcus aureus antibacterial value is maximum. With further reduce fiber adhesive content, fiber antimicrobial declined obviously. The results indicate that the anaerobic bacteria can’t survive in the inside of pineapple leaf fiber where exist a large specific surface-area, lots of holes and Voids, and much oxygen. Pineapple leaf fiber contains a lot of phenols and their derivatives which are effective natural bacteria resistant materials and inhibit the metabolism and physiology of bacillus and other microorganism,break the structure of germ, and repress the generation of bacillus until the death of germ.Moreover, the existence of a small amount of cannabinol is adequate to kill the microorganisms.

The micro-structural and formaldehyde adsorption abilities of pineapple leaf raw and degummed fibers are characterized by using SEM, FT-IR, chemical composition analysis and determination of acidic oxygen-containing functional groups and more other methods. Test results show that after being degummed, pineapple leaf fibers possess smoother surfaces, obvious grooves, better single-fiber separations and non-significant cross-sectional cavities. Hemicellulose’s characteristic absorption peaks disappear basically and their contents are reduced from 20.62% to 2.65%. The intensities of lignins’ characteristic absorption peaks drop and their contents are decreased from 3.68% to 1.20%. The locations of celluloses’ characteristic absorption peaks do not change too significantly and their contents are increased from 61.18% to 84.45%. The numbers of carboxyl, lactone and phenolic hydroxyl in acid oxygen-containing functional groups are reduced. Pineapple leaf raw fibers have higher formaldehyde adsorption abilities. After degumming, formaldehyde adsorption abilities of pineapple leaf fibers are similar, but all slightly lower than raw fibers.

This paper carries out detection on nutritional ingredients of pineapple leaf residue 3 days, 5 days, 7 days, 15 days, 25 days, and 35 days after ensiling respectively, and then carries out comparison and analysis with control group (0 day). It can be seen from experimental result that pH value of feedstuff rapidly decreases 15 days after ensiling and the feedstuff reaches the peak of fermentation, the moisture content obviously increases (P

The evolution characteristics of pore structure during the decomposition of limestone were experimental measured with nitrogen adsorption method. As a result, the pore structure of calcined limestone has a characteristic of bimodal distribution and the most probable pore sizes are about 3.8nm and 45nm. The probability ratio between the front and following humps decreases at first with the solid fractional conversion and then increases in the later stage of decomposition, and the corresponding inflection point of solid fractional conversion is aboutη=0.56 under the condition of calcination temperature 1133K. A probability density function with bimodal distribution for pore volume was established to construct the pore structure parameters model. As the average pore size decreased from 38.2nm to14.9nm, the effective diffusion coefficient of gaseous product through the porous solid product layer reduced from 0.0088cm2.s-1to 0.0017cm2.s-1, which leads to an increase in the pore diffusion resistance affecting the decomposition mechanisms of limestone.

Programmable constant-temperature/humidity test chamber owned by Natural Fiber Laboratory, Institute of Agricultural Machinery, Chinese Academy of Tropical Agricultural Sciences, is adopted to analyze undegummed pineapple fibers’ moisture absorptions. Study and analysis on moisture absorptions, moisture-absorption isothermsand moisture-absorption isohumes with constant temperature and inconstant humidities are carried out and the results show that fibers’moisture absorptions present roughly a regularity of such three stages as 0~20%, 20~80% and 80~100% (RH). In low-moisture stage, moisture absorption rates are higher; in middle-moisture stage, they level off; in high- moisture stage, moisture absorption rates are the highest. Fibers’moisture absorption amounts decrease along with temperature rise; but under the condition of high humidity, they increase along with temperature rise and also increase along with humidity rise. Study on undegummed pineapple fibers’moisture absorptions may provide theoretical basis for undegummed pineapple fiber preservation and textile processing in some special industries.

This paper proposes a novel parallel computing method of semantic similarity in linked data to solve such problems as low efficiency and data dispersion.It combines the existing similarity calculation method with MapReduce parallel computation framework to design the appropriate parallel computing method of similarity. First, three typical similarity computing methods and the parallel programming models are introduced. Then according to the MapReduce programming techniques of cloud computing, the parallel computation of similarity in linked data is proposed. The experimental results show that, compared with the traditional platforms, the parallel computing method of similarity on the Hadoop cluster not only improves the capacity and efficiency in the processing massive data, but also has a better speed-up ratio and augmentability.

Based on the multi-body system dynamics in the ADAMS environment, a virtual prototype of crane hoisting mechanism was developed. In this model, the whole system was disassembled lifting mechanism system with flexible body dynamics model of the wire rope. The virtual running environment was established according to the actual working conditions, which is designed the lifting working process with rope-movable pulley contact. It is the key step to build hoisting mechanism dynamics model for performance analysis of system dynamics, which is the basis for the optimize design of hoisting mechanism. Virtual prototype simulation results will be applied to prototype design and evaluation, and save a lot of manpower and material resources. At the same time, the method has an advantage for dynamics analysis to simulating some dangerous movement conditions, which is hard to be replayed or simulated at the test actual working condition site. In particular, some cases cannot be recurrence in the accident handling process. Variable stiffness contact characteristics of wire rope-movable pulley of hoisting mechanism are implemented successfully through discrete multiple rigid body are applied to the wire rope in this paper , the establishment of a crane hoisting mechanism dynamic model is based on ADAMS, which realize hoisting mechanism flexible simulations, running virtual environments of hoisting mechanism is established, these results show that the model reflected the actual dynamics of hoisting mechanism, also present that some of the theoretical analysis results cannot confirm.

A novel fly ash cenospheres supported Pt–BiVO4 composites (Pt–BiVO4/FACs) photocatalysts were prepared by modified metalorganic decomposition process, followed by photochemical reduction. The composites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), and UV–vis diffused reflectance spectroscopy (DRS) techniques. The results indicate that the visible light absorption of the Pt–BiVO4/FACs composite is greatly enhanced. The Pt element is present in the metallic form and disperses in the composite samples. Photocatalytic activities of the Pt–BiVO4/FACs composites were evaluated by the methylene blue (MB) degradation under visible light irradiation. The results indicate that the photocatalytic efficiency is significantly improved after the Pt species was loaded and the 2 wt% Pt-loaded composite showed the highest photocatalytic activity.

To determine the the fiber fineness in different parts of the old and young leaves. the pineapple leaf fiber of comte de paris was used as raw material, The results showed that, the length of fiber extracted from the old leaves of comte de paris pineapple ranged from 70 cm to 90 cm, and the average fiber fineness of the the tip and root were 14.13 dtex and 18.50 dtex, respectively. While the length of fiber extracted from the young leaves of comte de paris pineapple ranged from 45 cm to 65 cm, and the average fiber fineness of the the tip and root were 13.09 dtex and 15.03 dtex, respectively. Variance analysis reveals that the fiber fineness of root and tip in the old pineapple leaf showed significant difference (P

In a previous work researchers found that fluorinated acrylate (PHFDA)/styrene (PSt)/ sulfonated styrene (S) copolymer can enhance the viscosity of carbon dioxide (CO2) by factors greater than 100 at concentrations of 5 wt %. To further improve the efficiency of this copolymer, we apply the dissipative particle dynamics (DPD) method to investigate the link between copolymer molecular structure and the solution rheology. Results show that sulfonated copolymer molecules combine with each other and create self-assembly structures, which greatly thicken liquid CO2. We conclude that we should increase the sulfonation degree on the premise of a reasonable solubility. Using a further dissolving experiment, we finally fix the mole fraction of PHFDA, PSt and S on 60%, 24% and 16%, respectively. We test the viscosity of the improved copolymer with rheometer, results show that it can increase the solution viscosity 180-fold relative to neat CO2 at 334K and 28 MPa with a concentration of 2.5 wt %.

Flapping wing aerial vehicles continue to be a growing field, with ongoing research into unsteady, low Reynolds number aerodynamics and micro fabrication. However research into deformation and stress of flapping wing continues to lag, especially based on composites model. One flapping cycle was divided into twelve segments, and maximum defmortion and stress were calculated in each segment. The results show that the maximum sdeformation at the beginning stages of downstroke is 19% larger than the maximum deformation at the beginning stages of upstroke, and the maximum stress at the beginning stages of downstroke is 29.9 larger than the maximum stress at the beginning stages of upstroke. This research is helpful to answer that why insect wings are so perfect through long evolution, thus improving the design of flapping-wing aerial vehicles.

This paper studied the borehole stability in Liulin bituminous core reservoirs during under-balanced drilling. The equivalent depth method was applied to study the formation pore pressure. The floor drain test method was applied to study the ground stress. Core strength experiments combined with logging data were used in the establishment of core strength predicting model. Mechanics analysis model was founded to study the borehole stability in the core reservoir. According to the studying and analyzing results, the under-balance drilling in Liulin coal reservoirs enjoys good borehole stability.

The 25 years of rainfall data in Wuliangsuhai eastern river basin from 1986 to 2010 are summarized and analyzed based on two statistical methods. The two statistical methods named moving average method and Cumulative Departure Curve are applied to make a conclusion that the rainfall in 25 years has a downward trend and the rate of change become high in new century.

Doubly-fed wind power generator takes the largest share of wind energy. However, as the most important part, the speed-up gearbox is easy to be damaged. The existing researches about gearbox faults are mainly about gear fault, the study of bearing fault is relatively less compared with gear fault, expecially for the bearing fault of planet gear. This article presents a typical case of bearing fault about planet gear, which contains the cause of vibration behaviour and the analysis of fault.

This paper makes a prediction about the daily power generation of the photovoltaic power station in Wuhan International Exhibition Center by the application of multivariable grey theory model and compares the forecasted results with the real results. This research proves that the application of the theory of multivariable grey model on short-term prediction of photovoltaic power generation can achieve a good prediction effect, which also has certain engineering application value.

Eutrophication has led to severe water quality problems in aquatic ecosystems throughout the world. The assessment of trophic status for lakes may provide important and fundamental information for trophic state classification and eutrophication control. This paper assesses and analyzes the classification of eutrophication using three different methods in Wuliangsuhai Lake. The aim is to provide the reference for water quality improvement and aquatic environmental protection of the lake in arid area.

This paper studied the relationship of chlorophyll-a, total nitrogen (TN) and total phosphorus (TP) concentration based on the conventional monitoring data in 2013. The results showed that the concentration of chlorophyll-a (Chl.a) had obvious correlation with TN, TP in July and August, and there was no relationship in October. Furthermore, content of nitrogen is more relevant to chlorophyll-a than phosphorus by regression analysis. Therefore, it was indicated that nitrogen and phosphorus nutrients had intimated relationships with algae growth.

With the development of our country economy, more and more super tall buildings are being built. While its beauties attract the attention of the people and they provide sufficient and comfort space to our people, it is very important to evaluate and its safety during severe earthquake. In this paper , the research method is studied for the tall structures during severer earthquake based on the design experience and research of tall structures. Based on the mechanical and deformation characteristic of this tall structure, the bottom stories and stories above the strengthened ones are selected as the "key stories" to control the performance of the building. The structure is replaced by an equivalent single degree of freedom system corresponding to each mode and each equivalent displacement is determined using the proposed method.

The research on the fatigue life of butt welded joint has important significance to hoisting equipment’s design, development and using safety. This paper conducted a study on fatigue properties of the most widely used joint at hoisting equipment-steel Q235 butt welded joint’s, based on the improved linear equivalent structural stress method, the stress of the weld joint can be obtained, and the master S-N curve of Q235 weld joint be acquired through fatigue test, thus the joints stress distribution under different stress environment can be gained through improved linear equivalent structural stress calculation and the fatigue life of the joint can be realized at the master S-N curve. The stress distribution situation and the fatigue life of butt welded joint can be calculated by integrated finite element software, this have profound reference significance to hoisting machinery industry.

Removal of phenols from waters and wastewaters is an important issue in order to protect public health and environment. In an effort to develop an effective adsorbent for removal of phenol from aqueous solutions, fly ash cenospheres (FACs), the solid wastes generated from a coal-firing power plant, were modified with an amino-terminated organosilicon (γ-aminopropyltriethoxysilane, KH550). Surface properties of the KH550-modified FACs (M-FACs) were characterized by the X-ray diffraction (XRD), the scanning electron microscopy (SEM) and X-ray photoelectron spectra (XPS). The characterized results showed that KH550 was successfully grated on the surface of FACs. The effects of various experimental parameters such as solution pH, adsorbent dose, and temperature upon the phenol adsorption onto M-FACs were evaluated. The results showed solution pH had a major impact on the phenol adsorption onto M-FACs, the optimum phenol removal was observed around pH 7-9. The kinetic studies indicated that the adsorption process was best described by the pseudo-second-order kinetics, suggesting that the mainly phenol adsorption process was predominantly controlled by chemical process. M-FACs presented more than double adsorptive capacity as compared with FACs. The adsorption capacity of the regenerated adsorbents could still be maintained at 83% by the fourth adsorption-desorption cycle.

Aiming at the burst point time measuring device cannot timely show the burst point time measurement situation, a new measuring system was designed. The pulse signal when the ammo was outing of the muzzle and exploding was detected by APD, the light pulse was converted to voltage pulse through an amplifying circuit. The timing display module was designed, the timing circuit got the voltage pulse and timing, and then the burst point time would show on LCD. All the photoelectric detector module was fixed with the special mechanical properties. The system could increase the maximum detection distance effectively, improve its detecting precision, and display the burst point time immediately. With the simulation experiment, the system had no failing to get the burst point time, and owned a stable performance. This design can provide a reference for the optimization and improvement of the burst point time measuring device.

Ground-roll is an interferential wave existing widely in seismic data, and it is an important step in seismic data processing to suppress ground-roll. Wavelet Transform lacks of detecting the singularities of the signal with straight line or curve, and the method can separate the different waves at the same time because of Curvelet transform simultaneously has the characteristics of frequency and direction. The experiment results show that the Curvelet transform has better effects in ground-roll suppression.

Various chemicals emerge in environment and exist as mixtures with different forms and concentrations. Toxicity interaction by mixtures may pose potential hazards and risks to the environmental safety and human health. Recent data show that toxicity interaction within ionic liquid (IL) mixtures related with some certain component. However, how to determine the specific component in a mixture is not an easy work and needs more researches about it. Therefore, we investigated the toxicity of twelve groups of mixtures by using three ILs and one pesticide aldicarb as mixture components. Four binary and eight pseduo-binary mixtures were designed by equivalent effect concentration ratio ray method using EC5and EC50of individual component. The toxicities of single chemicals and these mixtures to a freshwater photobacteriumVibrio qinghaiensissp.-Q67 were determined by using the microplate toxicity analysis method. Toxicity interaction within mixtures were determined based on an additive referrence model, concentration addition (CA). The results showed that three binary IL mixture exhibited additive action and one antagonism. Interstingly, most pusedo-mixtures of aldicab and binary IL mixture exhibited cleary synergism especialy when they were mixed in the ratio of components EC5.

A novel attapulgite clay-based composite (BiVO4/attapulgite) was successfully prepared as a heterogeneous photocatalyst for degradation of rhodamine B (RhB) dye solution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and microanalysis by energy dispersive spectrometry (EDS), and UV-visible diffuse reflectance spectra (DRS). The results showed that monoclinic BiVO4particles were loaded successfully on to the surface of attapulgite fibers and were widely dispersed. The DRS spectrum reveals that the BiVO4/attapulgite composite had much stronger absorption in the visible light range of 420-800 nm. Correspondingly, the BiVO4/attapulgite composite showed significantly higher activity in degrading RhB solution under visible-light irradiation compared to that of pure BiVO4.

To determine the the fiber fineness in different parts of the old and young leaves. the pineapple leaf fiber of smooth cayenne was used as raw material, The results showed that, the length of fiber extracted from the old leaves of smooth cayenne pineapple ranged from 80 cm to 100 cm, and the average fiber fineness of the the tip and root were 14.40 dtex and 18.53 dtex, respectively. While the length of fiber extracted from the young leaves of smooth cayenne pineapple ranged from 50 cm to 70 cm, and the average fiber fineness of the the tip and root were 13.27 dtex and 14.77 dtex, respectively. Variance analysis reveals that the fiber fineness of root and tip in the old pineapple leaf showed significant difference (P

The gas-sensing properties of zinc doped lanthanum ferrite (Zn-LaFeO3) compounds for formaldehyde were investigated in this paper. Zn-LaFeO3 powders were prepared using sol-gel method combined with microwave chemical synthesis. The powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The formaldehyde gas-sensing characteristics for the sample were examined. The experimental results indicate that the sensor based on the sample Zn-LaFeO3 shows excellent gas-sensing properties to formaldehyde gas. At the optimal operating temperature of 250°C, the sensitivity of the sensor based on LaFe0.7Zn0.3O3 to 100ppm formaldehyde is 38, while to other test gases, the sensitivity is all lower than 20. The response and recovery times for the sample to formaldehyde gas are 100s and 100s, respectively.

A new TiO2-nanoSiO2 hybrid film is prepared through adding the nanosized SiO2 into the TiO2. A more environmental and simpler method is found to prepare CdSe quantum dots (QDs) sensitized TiO2nanoSiO2 hybrid films for the quantum dots-sensitized solar cells (QDSSCs) application. The prepared colloidal CdSe QDs (~2.6nm) was linked to the TiO2-nanoSiO2 hybrid film using 3-mercaptopropionic acid (3-MPA) as a linker molecule slowly with drop and drop. The power conversion efficiency of 1.33% was achieved using the sensitization photo-electrode prepared by using TiO2nanoSiO2 hybrid film modified with CdSe (TiO2-nanoSiO2/CdSe) under the illumination of one sun.

Though fatigue failure is often happened in steel gate, fatigue design has not yet been included in design or evaluation standards in China. In this paper, analytical theory based structural stress method and structural stress based fatigue analysis method are combined and employed for fatigue life evaluation of plane steel gate. The variation of water head is taken into consideration for the conditions of gate running and resting. In order to give a valid evaluation, the weld located among all components is considered as rigid connection when calculating structural stress. Master S-N curve in ASME code is used for life evaluation. Example shows the method can be used for fatigue analysis of plane steel gate, and can be used to identify fatigue failure zone.

Tongluoshan expressway tunnel passes through coal mined out area. It is an extra-long expressway tunnel with high-gas, so construction ventilation is the key in this project. Combined with the theoretical calculation and the actual situation of Tongluoshan Tunnel, the forced ventilation is taken as the major way of construction ventilation. Based on the calculation of required airflow, gas distribution in work area and calculation of air duct resistance and tunnel resistance, the configuration of fans is optimized, thus the construction ventilation of each section have been determined.

To avoid the problem of mutual interference of moving parts and errors of assembly appears in the prototype design stage, this article is based on virtual design idea, a small snow removal vehicle has been designed based on virtual design idea, using pro/e 3 d modeling software in this paper. 3 d modes of parts of the small snow removal vehicle and virtual assembly have been completed. The mall snow removal vehicle has a throw snow impeller, a built-in worm gear reducer and a helix-collect snow set. The motion simulation has been operated. The design of the small snow removal vehicle is right according to the studying of virtual assembly and motion simulation.

In this paper, the history and present conditions of welding robot were summarized in domestic situation and foreign situation, the latest development in technology was discussed. According to the structure and motion features of welding robots, using the UG simulation techniques can help us to establish the virtual prototype model of the robot easily, which can achieve the movement of the whole system analysis, dynamic analysis and so on. In this paper, the result of the application ADAMS simulation software is that the simulation mode provide reference for optimize the structure and drive mode design. It also was provided a possible scheme for the final optimal design.

In traditional frequency synthesizers, there is a frequency synthesis module for every output channel, so there is crosstalk between output channels. The more the output modules, the more is the crosstalk. Deeply researching shows that the crosstalk between output modules has most of the influence on output stray [2,. To improve the output stray, a new scheme of designing frequency synthesizer with low output stray is given in this paper. In the new scheme, there is only one frequency synthesis module for all outputs. The output of the module is divided into several outputs by the power divider. Then these outputs directly input to the output modules. In this way, the crosstalk between the frequency synthesis modules can be effectively avoided, and the output stray can be significantly reduced. On the other hand, the volume and the cost of the synthesizer is reduced. Simulation result shows that the new scheme can meet the requirements of low output stray.

The power loss and efficiency model of a planetary gear transmission system was built with a system modeling method. The method takes many transmission elements such as gear, planetary gear sets, hydraulic torque converter, friction disk, lubrication, sealing, bump and motor etc. into consideration and calculates non-load and load power loss for each element. The overall calculated power loss and efficiency is more accurate than the meshing power method. To make simulation more reliable it is compared with the test data. In the paper some planetary gearbox is selected and its power loss and efficiency were measured from the experiment. The power loss and efficiency of each gear of the planetary gearbox are compared and verified and corresponds well with the test data. The power loss error drop from 10% to 5% with the system method compared with meshing power method. It shows that the system method for power loss and efficiency analysis is more reliable. It provides important basis for engineers to improve design and reduces the power losses. It provides solutions to increase the planetary gear transmission efficiency and finally makes the whole vehicle lighter and the power density higher than before.

Our team proposes the design concept of layered composite electrode materials. Change the single substrate of traditional electrode material by using thermal pressing diffusion welding to synthesize sandwich structure electrode substrate of titanium cladding aluminum. Only Al3Ti phase is obtained in the composite interface. First-principles calculations have been used to calculate the formation enthalpy and binding energies, and the respective order of their value are as follows: AlTi32Ti3Ti,AlTi32Ti3Ti. AlTi3 near Fermi surface is zero and it has good conductivity. It has the strongest bonding capability and stability. Practical application of this new anode in the field of hydrometallurgy has good conductivity, strong adaptability.

With the rapid development of wind power in recent years, the wind power industry has gradually shifted from infrastructure construction to equipment operation and maintenance. The importance of the operation and maintenance of the wind turbine is increasingly apparent. A new vibration monitoring mode of wind turbine, called distribution acquisition-Centralized analysis, has been established by full investigation and study. This mode involves information technology, electronics technology and automation control technology. It is based on the mechanical movement principle and the principles of mechanics analysis. Throughout the one-year application of this vibration monitoring mode in wind farms, it is obseraved that: this model can grasp the operational status of the key equipment of the wind turbine, and effectively identify potential failures in a timely manner. This mode reduces costs of maintenance, improves equipment reliability and extends equipments operation time.

This paper studies the related problems which belong to research of digital content platform by using numerical simulation. Results from the research show that: the Nash-equilibrium is not the optimal outcome in the R&D competition. The government should pay attention to the continuity of investment. The larger the conversion rate of the user scale, R&D investment allowance rate and the foresight of companies are, the more the technology stock and consumer welfare are.

As a porous medium, the strength of cement-based materials is significantly affected by its porosity. This paper presents a new method to describe the strength development of cement-based materials as a function of porosity based on a developed microstructure hydration model of cement. The hydration model deduces the relationship between the diameter change of cement particle and time based on Krstulović-Dabić hydration kinetics formulas and extends a broader version by considering the effect of water reduction, temperature variation, interfacial contact area between hydration products and free water on the hydration rate. Using the hydration model, the time-varying development of porosity can be obtained. Then, based on the strength model proposed by Maekawa et al, in which both the present and initial porosity are taken into account, a new method was established to predict the strength evolution with the porosity calculated by the hydration model.

Because of the battery replacement confined by physical conditions, the battery energy limit of the sensor nodes becomes one of the most critical constraints in the design of the entire sensor network , which directly determines the network life. The basic idea is to close sensor nodes within the device when it is not needed, and awaken them if necessary so that the sensor can reduce overall energy consumption. This paper compares the autoregressive model and moving average model in time series analysis. Simulation results show that after dynamic power adjustment, it can reduce energy consumption, extend the entire life cycle of wireless sensor network..

To study the impact of atmospheric Cd exerts on the soil accumulated of Qingdao urban area, atmospheric dust and soil samples are collected and analyzed. Based on these tested samples, this paper firstly analyzed the geochemistry characters of Cd in atmospheric dusts and soils using the statistic analysis method. Then according to the time accumulation model about the influence of Cd exerts on soil, this paper predicates the influence that atmospheric Cd in dust exerts on soil 20 years later. Analysis results show that atmospheric Cd has great influence on the accumulated soil. For example, it can cause the deterioration of soils quality. Therefore, to prevent soil from Cd pollution, the detection and control of atmospheric Cd should be strengthen.

The resources of wireless sensor nodes are limited, and the power of nodes is supplied with battery whose capacity is very limited, once the energy of battery is run out, the nodes will lose their effect, so there are serious energy constraint in wireless sensor network. In this paper, the specific energy consumption of sensor nodes is studied by experiments, the energy experimental hardware platform is established with the low power consumption SCM MSP430F135 and wireless transceiver chip CC2420, the relationship of energy consumption and communication distance for nodes is discussed, and the energy management strategy of effective wireless greenhouse monitoring system based on dynamic power management is put forward and discussed, the mobile structure is adopted in the convergent nodes. The experiment and simulation results show that the energy consumption of nodes is proportional to the third power of communication distance, the communication distance of sensor nodes can greatly shorten, and energy consumption is saved.

This paper studies the related problems which belong to research of digital content platform by using numerical simulation. Results from the research show that: under effect of network externality, the digital content platform with high-tech stock could only expand successfully when the network size beyond critical capacity. But, when the technological gap is big enough, the critical capacity could be 0. Besides, we found the Nash equilibrium of R&D input is not necessary exist in the simulation without price, and the existence of equilibrium need special condition.

The strengthening mechanism, properties and applications of magnesium alloy with resistance to high temperature and creep resistant were introduced. The effects of some kinds of elements in magnesium alloy and the preparation methods were also elaborated. At last, the development trend of magnesium alloy was overviewed.

Based on thermal stability research, a binder for dry vibrating refractories was selected. A new environment-friendly dry vibrating refractory was prepared by adopting the selected binder. The permanent linear change, apparent porosity, bulk density, cold crushing strength (CCS) and modulus of rupture (MOR) of the specimens were tested by the chinese national standard. The dry vibration refractories were successfully used in the lining material for continuous casting tundish.

The Li-ion battery has high discharge voltage, long cycle life, good safety performance, no memory effect and other advantages. So it has being more and more used and concerned. This paper reviews various aspects of recent research and developments in Li-ion battery prognostics and health monitoring,and summarizes the techniques,algorithms and models used for state-of-charge estimation,voltage estimation,capacity estimation and remaining-useful-life prediction. Especially for state-of-charge estimation, this paper summed up many methods, such as current integration method, open circuit voltage method, Fuzzy logic, Autoregressive moving average model, Electrochemical impedance spectroscopy, Support vector machine and support vector machine based on Extended Kalman filter. And their advantages and disadvantages are summarized.

DC transformer with high frequency and efficiency under a fixed duty cycle is widely used in dc distributed generations. In this paper, the topologies and equivalent circuits of single /bidirectional full-bridge non-resonant DC transformers are presented. And the configurations of the input-series output-parallel and input-parallel output-series DC transformers are also proposed for reducing voltage stress of power devices. The example consisting of DC transformers in a distributed generation system based on DC grid is shown. Finally, simulation results verify the feasibility.

One of the characteristics of the network economy is the emergence of digital products. Digital products, the core of the network products, the pricing issue has drawn increasing attention. Precisely because of the network externalities demand-side economies of scale, positive feedback and increasing marginal returns and other features of the network economy, as well as the characteristics of high initial investment costs and low marginal costs of the digital products, digital products cannot be simply priced by traditional economic pricing method. Monopolist does not like the traditional monopolist which limits production and raises prices to earn high profits. Of course, the manufacturers will not simply rely on the demand and supply in accordance with the marginal revenue and marginal cost pricing. Therefore, based on the characteristics of the digital products itself, cost of production, network market environment and the characteristics of the analysis of the consumers’ behaviors, proceeding from the point of view of the network expansion, then the theory of groups pricing based pricing strategy is put forward.