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Finding the new type of sustainable and green energy is the key point to solve the problem of energy shortage and meet the requirement of intelligent roadway. Technologies of harvesting energy from the roadway environment have been paid more and more attention. To promote the research and development of energy harvesting from roadway, technical approach and research status of energy harvesting from roadway are reviewed. Development direction and hot issues in the future are proposed for utilizing multiple kinds of integrated energies.

Anisotropic wet etching of high resistivity silicon by TMAH for the fabrication of large area silicon radiation detectors is studied in this work. TMAH is widely applied in microelectronics and micromechanical fabrication etching low resistivity silicon, whereas the etching of high resistivity silicon was seldom studied by the industry. This work focused on the research of TMAH etching of high resistivity lager area silicon wafer aiming at its application in silicon radiation detector fabrication. We investigated the etching properties of TMAH of 4 inch (111) silicon wafers. Various parameters combinations were explored, such as TMAH solution concentration of 25wt%, 15wt% and 5wt%, and temperature of 95 °C, 90 °C and 85 °C. Etch rate, etch uniformity and silicon surface roughness were observed.

The ZnO varistor ceramics were fabricated through microwave sintering at 800~1150°C using ZnO powder doped and undoped TiO2 prepared by planetary ball mill. And the effects of milling time, sintering temperature and doping on microwave sintering technique have been studied. The result shows that the powder is more homogeneously and with smaller particle size with the increasing of milling time, therefore the electric properties is improved. However the particle size and the electric properties tend towards stability after 20h milling time. The density and electric properties increase with the increasing of sintering temperature, but decrease sharply at 1100°C, so the best sintering temperature is 1100°C. Doping TiO2 improves the electric properties of ZnO, however the electric properties decrease with more than 2.5% doping.

The technological parameters on synthesis rate of ITO nanometer by chemical coprecipitation were investigated. The effects of process parameters on synthesis rate of ITO nanometer powders were discussed by the range analysis of orthogonal experiment design. The dispersion features of ITO nanometer powder by ultrasonic dispersion or without were compared. The results show that the biggest factor that affects the powder synthesis rate is the pH at the titration end-point. Powder synthesis rate increases with the increase of pH value. When pH is 9, the powder synthesis rates are all above 90%. TEM images show that ITO nanometer powders are well dispersed without obviously agglomeration when anhydrous ethanol is used as dispersant. Particles have diversity of shapes, and the particle sizes distribute widely. After Ultrasonic physical dispersion, ITO nanopowders are well dispersed with no obviously agglomeration, narrow particle sizes of 20-30 nm and the approximation spherical particle morphology.

Fe, N)-codoped TiO2 were prepared by calcining the Fe-doped TiO2 samples accomplished by precipitation method in the nitrogen atmosphere, and the photocatalytic properties of (Fe, N)-codoped TiO2 at different temperatures were investigated. The samples were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and ultraviolet-visible (UV-vis). The results show that the (Fe, N)-codoped TiO2 powder samples calcined at 600°C are dispersed well with more hydroxyl groups on its surface. The absorption edge of the (Fe, N)-codoped TiO2 is 429nm due to the effects of mixed crystal, which means the improvement of photocatalytic capability.

The glass powder as a binder phase in the silver paste mainly plays the role of binding. The composition, content and particle size of the glass powder have significant effects on the properties of the silver paste. In this paper, the effects of the sintering temperature, holding time, glass powder content and glass powder size on the adhesion and square resistance of the silver film were studied. The research results showed that when the glass powder content was 6%(in mass) of the total silver paste, the sintering temperature was 680°C, the holding time was 7 minutes and the glass powder size was 2.47μm, the silver paste can get good properties. The adhesion strength and square resistance of the silver film were respectively 2.5 N/mm2 and 14 mΩ /.

Based on the density functional theory, this paper calculated the geometrical and electronic structural properties of ZnO(11¯20) surfaces and analyzed ZnO(11¯20) surfaces in the structural relaxation, electron density difference, densities of states and the Ti adsorption by using the first-principles and pseudopotential method. According to the computing result, ZnO(11¯20) surfaces are similar in geometrical structure and bulk; at the same time, when Ti adsorbs ZnO(11¯20) surfaces, the negative charge density is special high in the central region between Ti and O, and Ti-O shows obviously better performance than Zn-O in covalent bond, for the reason that the number of outer electron transferred from Ti to O is extremely limited, and the area of negative charge of the surface is large, which can lead to metallic characteristics on the surface

Composite membranes comprised of a thin poly (N,N-dimethylaminoethyl methacrylate) layer and a microporous polysulfone substrate were prepared by coating method. The effects of parameters involved in the membrane preparation procedure on the permselectivity of the resulting membrane were investigated by a factorial design. The permeability of the membrane to N2, CH4 and CO2 was tested and the membrane showed a high permselectivity to CO2.

The aim of this study is the removal of endotoxin from water using a positively charged microfiltration membrane. The membrane was prepared by crosslinking a chitosan (CS) coating layer with glutaraldehyde vapor on a cellulose (CA) microporous substrate. The positively charged CS/CA membrane showed promising removal efficiency of endotoxin at a high water flux.

This paper, based on STM32 and nRF905 wireless module, introduces a wireless temperature gathering and transmitting system. From RF modules and master control module, the hardware platform has been designed, beyond that, the paper introduces the temperature sensor network software design. The test show that the system is stable, and datas are reliable.

The purpose of this paper is to analyze the electromechanical properties of piezoelectric harvesting unit from road vibration. A new kind of piezoelectric harvesting unit, which consists of 8 pieces of PZT vibrators and sizes of 280*280*20mm, is purposed. The vibrators are connected and covered by epoxy resin. With the software of ANSYS, open circuit voltage and stress distribution of the unit under the function of vehicle tire pressure are analyzed. The results show that the maximums of open circuit voltage and stress distribution are proportional with the tire pressure. When the tire pressure is 1.0MPa, open circuit voltage and the maximum stress generated by the piezoelectric unit are 950.8V and 9.8MPa, respectively. It means that application of the piezoelectric harvesting unit can couple with the asphalt pavement very well and harvest higher electricity from road vibration on larger area.

Air environmental quality data (SO2, NO2, and PM10) of six automatic monitoring points monitored in 2010 and fuzzy clustering analysis method were applied to regionalize the atmospheric functional regions in Baotou City. It was demonstrated that the atmospheric functional regions were divided into two classes, which is consistent with the regional actual situation. This study provides a scientific basis for the comprehensive improvement of the urban environmental planning.

To open up a new way of green energy, the piezoelectric harvesting technology from road vibration is proposed. Research status at home and abroad is reviewed, some existed problems are pointed out. With the software of ANSYS, the arrayed space between piezoelectric vibrators and the material and thickness of substrate are chosen in the light of higher harvesting energy and better coupling properties. From the simulation results, can a unit of 280*280*20mm be determined. When it is embedded under 40mm asphalt concrete pavement, 1.785MW electric power can be harvested from each traffic lane and per kilometer. This shows that application of the piezoelectric harvesting unit has very nice optimistic prospects.

The industrialization of gelcasting technique has been prevented because acryamide is a neurotoxin monomer. In this paper, a low-toxicity gel system based on the polymerization of low-toxicity N-hydroxymothl acrylamide was used for the gelcasting PMN-PZT piezoelectric ceramic. The effects of monomer concentration, the dosage of initiator and catalyst, pH value on polymerization were studied. The results showed that the condition suitable for gelcasting PMN-PZT piezoelectric ceramics could be obtained while monomer concentration was 10wt%～15wt%, the dosages of initiator and catalyst were respectively 0.4 vol%～0.5vol% and 0.4vol%, pH value of slurry was about 10. The highest bending strength of PMN-PZT green body prepared at the aboved conditions can reach 19.5Mpa

In this paper, unlike the traditional powder metallurgy technology, the titanium hydride is directly used as the starting material to manufacture the titanium and titanium alloy. Thermogravimetric and dilatometric techniques are performed to study the dehydrogenation and shrinkage of TiH2 powders with different particle sizes. The process factors such as the sintering temperature, the sintering time, the heating rate, the compaction density, the compaction methods, and the alloy system, would affect the sintering densification of TiH2 powders and TiH2-Al-V alloy powder. The results shown that the dehydrogenation temperature of the starting and ending of the ball milling TiH2 is lower than that of the coarse TiH2 powders, the finer the TiH2 powder, the lower the temperature. The densification of TiH2 powders is easy due to the combination of dehydrogenation and shrinkage of α-Ti in one process, which creates the fresh dehydrided titanium uniform during sintering, thus leads to rapid densification and very high sintering relative density, higher than 99%. In contrast, it is difficult to achieve a full densification of TiH2-Al-V alloy powder during sintering, which requires dissolution of alloy elements during sintering above its beta transformation temperature. The sintered microstructure of Ti-6Al-4V shows the typical lamellar shaped α+β characteristics, with a uniform alloy element distribution.

After polymer flooding was put into effect in DaQing oilfield, eccentric wear of sucker rod and tubing has been so serious that it made the rods break. This is because production liquid produced from normal wells is pure viscous fluid while liquid produced from polymer flooding oil wells is viscoelastic fluid. The flow equation of viscoelastic fluid in eccentric annulus was established in cylinder coordinate system, and the velocity distribution was solved. Based on upper-convected Maxwell constitutive equation, the normal stress calculating model of viscoelastic fluid acting on sucker rods was established. The normal stress of viscoelastic fluid acting on inner rod in eccentric annulus was measured under different experimental conditions indoors. The result proves that normal stress is the main reason of eccentric wear.

Based on Discrete Element Method(DEM), initial state models of steel balls were establisheded by Particle Flow Code in three Dimensions (PFC 3D), the initial void rate of steel balls at different filling rate were calculated. The results showed that at the same filling rate, the initial void rate of steel balls decreased as steel ball’s diameter decreased. The initial void rate of steel balls with one diameter and grading steel balls both increased gradully as ball filling rate increased, but the initial void rate of grading steel balls were smaller than that of steel balls with one diameter. The Stratification phenomenon will occur after steel balls in grading scheme reached to the initial equilibrium sates, that is, Large steel balls moved near the mill’s center, but small steel balls moved away from the mill’s center and close to the cylinder of mill, which is benifical to improve grinding effeciency.

Based on Discrete Element Method(DEM), movements of steel balls in ball mill were simulated by Particle Flow Code in three Dimensions (PFC 3D), the motion states of all steel balls and balls with one diameter were discussed respectively at different ball filling rate. The results indicated that steel balls moved from cascading motion gradually to throwing motion with the increasing of rotary speed rate, and became centrifugal motion after rotary speed rate exceeded certain value. When rotary speed rate unchanged, the translation speeds from cascading to throwing or from throwing to centrifugal motion accelerated as steel balls’ diameter decreased. The segregation of steel balls was more obvious with the rising of rotary speed rate and lead to steel balls’ lamination that big balls moved in the inner and small balls moved in outer layer of the mill. Lamination of steel balls is benefical to crush different size minerals and improve grinding efficiency.

Gong Zutong academician guessed that the structure of the photon may be similar to the hydrogen atom which consists of a negative charge and a positive charge with the equal power, and the negative charge rotates around the positive charge in a spherical orbit. Based on this conjecture, to establish respectively the equation of photon movement for the dual-slit interference and single slit diffraction experiments. To get respectively the light intensity distribution model using complex integration method. Finally, to get that the width of the diffraction pattern of the conjecture is obviously wider than the results of Born through mathematical simulation in MATLAB software.

Reservoir X is a fractured-porous dual-media reservoir. According to the geological conditions and exploration and development statuses of reservoir X, this paper designs a long-core experiment and then carries it on. As a result, the diffeSubscript textrent enhance displacement efficiency effects under different driving methods (water flooding, gas flooding, WAG, pulsed gas injection, gas slug flooding) and different driving media (flue gas, CO2) are obtained. The results show that among all those driving methods, water alternating CO2 injection (WAG) reaches the best effect. WAG has an injection rate of 0.8HCPV and enhances displacement efficiency by 26.93% on the basis of water flooding. The injection rate of gas slug/water flooding after CO2 slug flooding is 0.3HCPV and these two methods have similar good results, 13.66% and 13.95% respectively. So considering the economic factor, we draw a conclusion that water flooding after CO2 slug flooding is the optimum choice.

Heavy-duty gas turbine is used widely in power generation industry for many advantages. Gas turbine exhaust system is an important component of the gas turbine. The work to study the exhaust system was less in the past. In fact, structure design of the exhaust system has important influence on performance and life of the gas turbine. In this paper, the three-dimensional structural model of gas turbine exhaust system is built, the thermal field and stress field for the exhaust system are analyzed by using finite element method (FEM). The maximum stress and distribution characteristics of stress field, the highest temperature and distribution characteristics of thermal field in the exhaust system are computed. These provide a reliable basis for reasonable design and safety evaluation of the exhaust system in gas turbine.

Porous alumina ceramic was prepared using sodium dodecyl benzene sulfonate (SDBS) as foaming agent by the combination method of gel casting and foaming. The effect of solid content on the line shrinkage rate, the porosity, the fracture strength and the microscopic structure of porous aluminum ceramic were studied. The result showed that when solid content increased, the line shrinkage rate of porous alumina ceramic decreased form 20% to 1.2%, the total porosity first increased and then decreased from 43% to 57%, the fracture strength first decreased and then increased from 23MPa to 41MPa. SEM indicated that alumina ceramic had more open pores when solid content was too low, the number of closed pore increased along with solid content rising, when solid content was too high, pore size distribution uniformity decreased.

The genetic algorithm converges faster compared with the traditional optimization algorithm, the global optimal solution can be quickly obtained and it is very effective for multi-peak function optimization. A milling process parameter optimization model is established for titanium based on genetic algorithm in this paper, the relevant constraints is considered and the optional titanium milling parameters is achieved based on the targets of maximum production efficiency and minimum cost, utilizing MATLAB optimization software to program, the best combination of cutting parameters is got finally. Experimental results show that the cutting efficiency and production costs are significantly improved with the optimized cutting parameters, so that the defects of low efficiency in CNC machining resulting in relying on experienced cutting parameters is overcome.

Preparation of aqueous ceramics slurry with high solid volume and low viscosity is premise and key step of gelcasting, and dispersant play important role in slurry preparation. In this paper, triammonium citrate (TAC) was used as dispersant of PMN-PZT piezoelectric ceramics slurry, the effects of TAC on slurry stability and rheological properties and dispersion mechanism of TAC were investigated by sedimentation test, viscosity, scanning electron microscopy (SEM) and FTIR analysis. The SEM results indicated that TAC could reduce the agglomeration of powder particles and make ceramic particles well-dispersed. FTIR indicated that strong chemical absorption occurred between TAC and PMN-PZT powder, and slurry stability and rheological properties of PMN-PZT slurry were improved through electrostatic interaction of TAC. The effects of TAC on sedimentation volume and viscosity have similar tendency. When TAC content was 7.5vol% and pH of slurry was about10, PMN-PZT slurry suitable for gel-casting could be acquired.

In cognitive radio networks (CRNs), cooperative spectrum sensing technology could overcome the impact from shadow fading and noise uncertainty; however, cognitive radio users with different signal-to-noise ratios (SNRs) would cause the unreliable detection performance when making a decision in the information fusion center. Therefore, a novel cooperative spectrum sensing scheme which focus on the reliability of cognitive radio users is presented. The proposed approach does not select all of the cognitive radio users but the ones whose SNR is beyond the average SNR of the whole users for high reliability. Moreover, the detection and throughput performance is investigated. Simulation results illustrate this approach could enhances the detection probability by comparing to the conventional cooperative algorithm. Besides, it also could lead to higher throughput within a short spectrum sensing time.

In order to solve the different problems which are a lot of data, complicated calculation, the issue of reports of calibration records and calibration certificates slowly, difficult management in unity and soon. The design in multi-parameter on-the-spot calibration is offered in this paper. The system can mange the things met in test efficiently, such as, the dynamic pressure, static pressure, temperature, noise, vibration, static strain. Specially by using the center&sub database the problems of the on-the-spot calibration scattered and the data management concentrated are overcome, the work efficiency is improved greatly.

Analysis of the relationship between defrost and the temperature and humidity. The design is SCM for the control of the core, to improve the greenhouse wall surface temperature, is used for defrosting, coating and ventilation dehumidification. Thus, achieve the purpose of defrosting and Dehumidification. Practice is proved that the system is less affected by environmental factors and has wide range of applications.

Porous alumina insulation materials were prepared by the combination method of gelcasting and foaming. The effects of the amount of blowing agent, the solid volume, and the sintering temperature on porosity of aluminum oxide ceramic were studied. The result showed that, when the amount of blowing agent is 1wt %, the solid volume is 45vol % and the sintering temperature is 1500°C, the porous alumina ceramics with high porosity, small pore diameters, evenly distributed, high bending strength and low heat conductance can prepared.

On the basis of the mechanism of ions precipitation reaction equilibrium, the thermodynamic analysis of Men+(La3+, Ni2+, Fe3+, Al3+)-CO32--NH3•H2O system was discussed in this paper. The relation curves between total concentrations of each metal ion and pH values at different total ammonia concentrations cN and total carbon concentrations cC were obtained. The suitable pH value of the complete precipitation reaction for all metal ions was also determined. It shows that when cN = 0.010 mol•L-1 and cC = 1.000 mol•L-1, the optimal pH is 9.0 to prepare the doped titanium dioxide powders by coprecipitation-coating process and using NaHCO3 and NH3•H2O as the precipitants.

SnO-B2O3-SiO2 glass powders, in which the different contents of SnO and B2O3 were 35% ~ 70%wt and 26% ~ 61% wt respectively, were prepared through high-temperature melting, water quenching and Ball milling. XRD showed that the performance of forming glass was very good and the range of extension was very wide. The effect of the contents of SnO and B2O3 on Tg, acidoresistant and density of prepared glass was studied. IR showed that it generates the heavy metal oxide generated glass. The density of glass powder decrease with increase of B2O3 content, but increase with increasing SnO content. SnO-B2O3-SiO2 glass had excellent chemical stability. Differential thermal analysis (DTA) shown that, with increasing SnO content, glass transition temperature first lower and then decreased.

The micro-sized silver used for solar cell grid electrode was obtained from silver nitrate via chemical reduction under ultrasonic wave and alkaline environment using polyethylene glycol (PEG-6000) as dispersant and alcohol as surfactant, and after agitation, the sol was filtered, washed and dried at constant temperature. The PEG and alcohol protective mechanism in the preparing process of spherical silver particles was studied. Effects of the amount of dispersant, pH, dosage of alcohol, were investigated. The silver powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Results show that with 0.35mol/LAgNO3 solution, 25mL ethanol, T = 40°C, pH = 8 and 10min ultrasonic wave, spherical silver power about 1.38 ~ 2.11μm with narrow particle size distribution was fabricated. The paste prepared with ready-made silver powder was printed on the silicon and the contact resistance is very low, indicating the electrical property of the prepared silver is qualified for solar cells.

ZnNb2O6powders were prepared by solid phase method and molten salt method. KCl-NaCl-ZnCl2was used as molten salt. The mass ratio of molten salt and raw material is 1:1. Pure ZnNb2O6powders were synthesized by molten salt method? at 650°C, which was reduced by 200°C relative to solid phase method. ZnNb2O6powders preferably grow along special direction, and appear strip or rod like. ZnNb2O6powders calcined at 650°C have narrow particle size distribution. Median size D50 =5.31μm. With the increase of the calcining temperature grain grows and particle size increases.

Using the high-energy ball milling craft, the case that the silver powders’ changes along the condition of ball milling is researched by the orthogonal experiment methods, the laser particle analyzer and the scanning electronic microscope. The influences of the milling times, the dispersant agents, speed and ratio of ball to powder on the distribution of particle size, the shape of grain and the specific surface are studied. The results show that, by using the composite dispersant agent, milling for 20h,ethanol as grinding aids and calcium stearate as dispersing agent, powders of average diameter is 8.55μm and specific surface area is 0.67(m2/g), with higher laminarization and less reunion of ultrafine flake silver powders.

Preparation of hydrophobic and oleophobic ABS laminates by a template method or additives added method and hydrophobic and oleophobic mechanism of ABS were investigated. ABS laminates with micro/nanopores were fabricated by adding additives and dissolving the micro/nanomaterial on surface for forming pores, and with low surface energy were prepared by adding nanometer titanium dioxide (TiO2) and silicon dioxide (SiO2). The contact angle of ABS laminates with oil and water were tested by the contact angle meter. Surface microstructure of the ABS laminates were observed by SEM. The results show that the contact angle of the Al-ABS laminates treated by diluted hydrochloric acid with water is 117° increase 67°than the contact angle of ABS laminates without any treatment, which was since aluminum particles on the surface of ABS laminates are dissolved by diluted hydrochloric acid and form rough surface morphology with the surface micro/nanostructure.

In order to improve the dispersion of TiO2, use the surface coating technology to form the aluminium ion film on the surface of TiO2, so as to achieve the aim of modification. Use the aqueous solution sedimentary drying method to make the alumina coating experiment under as certain technical condition, use the test like the scanning electron microscopy and transmission electron microscope, etc to analyze the coating powder’s dispersive and coating situation. The paper started from the angle of ion sedimentary reaction equilibrium, made the thermodynamics analysis on the coating on the surface of TiO2 and got the [Al]T-pH relationship diagram about the aluminium ion, and then confirm the PH extent for the aluminium ion’s completed sedimentation. The result indicated that, when the PH value reached from 8 to 12, the aluminium ion would completely precipitate.

By using low-power Toshiba microcomputer TMP86FH09ANG and capacitive touch-detecting chip CY8C21534, a control and display system of infrared cooker was designed. Its input and output are touch-sensitive buttons and LED respectively. The chip CY8C21534 can sense any changes of the capacitance of the touch-sensitive buttons. According to keyboard inputs, the corresponding operations such as power on/off, plate selection, fire adjustment, timing and child locker can be realized. The diagram of hardware circuit is presented in detail, and the software functions are introduced. This design can be reference to the development of related products.

To solve the problem of detecting the permeability of the textile machinery, a dedicated test system has been developed based on the pressure difference measuring method. The established system has a number of advantages including simple, fast and accurate. The mathematical model of influencing factors for permeability is derived based on fluid theory, and the relationship of these parameters is achieved. Further investigations are directed towards the inherent characteristics of the control system. Based on the established model and measuring features, an information fusion based clustering control system is proposed to implement the measurement. Using this mechanical structure, a PID control system and a cluster control system have been developed. Simulation and experimental tests are carried out to examine the performance of the established system. It is noted that the clustering method has a high dynamic performance and control accuracy. This cluster fusion control method has been successfully utilized in powder metallurgy collar permeability testing.

Micro-arc oxidation coatings were prepared on magnesium alloy AZ91D substrates at the different applied voltages in aluminate solution. The morphologies, phase components, and corrosion resistances of the coatings were investigated. The effect of the applied voltages on the microstructure and corrosion resistance of the coatings was also discussed. The results indicate that the coatings are uniform in thickness, and mainly composed of MgAl2O4 and MgO. There were many residual discharging channels on the coatings surface. The coatings improved the corrosion resistances of magnesium alloy AZ91D considerably. With the increase of the applied voltage, the thickness and the MgAl2O4 content of the coatings increase, while no significant variation is observed in the MgO content. The coatings surface becomes lower porosity and larger pore size with increasing of the applied voltage. In addition, the corrosion resistances of the coatings on magnesium alloy AZ91D surface are obviously superior to the magnesium alloy AZ91D substrate in the 3.5 wt. % NaCl solutions, and the effect is more remarkable at higher voltage.

The effects of sintering temperature on microstructure, micro-composition, barrier structure and electrical properties of TiO2 varistors ceramics were investigated. The microstructures and chemical compositions of grains in TiO2 ceramics were measured by SEM and EDS. Based on the thermo electronic emission theory, Grain boundaries barrier structure was calculated by analyzing electrical properties of samples. The sample sintered at 1350°C exhibits better microstructure and properties. The grains size of the TiO2 sample sintered at 1350°C is about 15m, and other electrical properties are as follows: solid solubility of donor doping Nb5+ cation solute in TiO2 grains of 1.49mol%, barriers height of 0.28ev, barriers width of 48nm, varistor voltages of 5.25V/mm, non-linear coefficient of 4.2 and relative dielectric constant of 1.1×104.