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The electricity shortage can be effectively alleviated by developing household photovoltaic power system in vast rural areas, it is necessary to establish simulation models. In this paper, the dynamic modeling of household photovoltaic power system including photovoltaic,Cuk-chopper circuit,battery and a single phase PWM inverter have been made in the ElectroMagnetic Transient Program /Alternative Transient Program(EMTP/ATP) software package.Control strategy based on MPPT for the power control of the inverter have been also developed. Operation characteristic of household photovoltaic power system was developed. Simulation results proved the validity of the model.

Combining the energy limit theory and the ANSYS finite element simulation analysis, this paper has designed the new integrated quartz crystal resonator and has used oscillator circuits to carry on the experimental comparison on its temperature-frequency characteristic in high-low temperature chamber. The experimental results show that the curve of its temperature-frequency characteristic is cubic in the coordinate system, which is basically consistent with that of the single electrode resonator. The frequency change of each resonator on the same substrate is basically the same when they are in the same circumstance and stimulation. According these similarities, this paper can implement differential processing on output frequencies of different resonators on the same substrate, which can effectively restrain the influence that temperature imposes on frequency.

By analysing the wafer, the electrodes, etc. according to the energy limit theory and the ANSYS finite element simulation, in this paper the author has designed the integrated quartz crystal resonator and oscillator circuit, and has carried on the experimental comparison on the stability of the integrated resonators, which have different structure, different electrode material and thickness. The experimental results show that the frequency stability of quartz crystal resonator is not only related with the electrode material and thickness, but also related with the structure. Under the same condition, resonator of asymmetric structure has better frequency stability, and the stability of Au-electrode was better than others, and its magnitude could reach 10 10. With the increase of the electrode thickness, the resonator oscillator stability will be improved.

In this paper, by studying a lot of advanced electronics manufacturing enterprise production management mode, put forward a basic structure of complete quality control system, and the elements of this structure is introduced in detail. Practice has proved that These practices on the establishment of "stable process" and improve the "product quality" has a very effective role.

Analyzing stress distribution of the thin circular quartz wafer subjected the radial force through the ANSYS finite element simulation, as well as the theoretical simulation, this paper designed two integrated quartz resonators with different structures and carried on experiments on force-frequency characteristic of resonators. The experimental results show that the resonators force-frequency characteristic is not only closely related to adding force azimuth, but also the electrode size and position. And when force azimuths are same, integrated resonator with asymmetric structure has better force-frequency characteristic, its force-frequency conversion coefficient could achieve 551.8Hz/N after electrode was evaporated with Au.

Relying on its abundant water resources and strong technical supports, Wuhan has overcome the deterioration of water environment, ecosystem degradation, and the lag in environmental protection facilities construction. Wuhan recent years hammers at finding ways to protect and rehabilitate water environment through managing sewage, building ecology network of rivers and lakes, and also developing a train of system construction. By the approaches mentioned previously, the achievement on meliorating quality of water within Wuhan is surely unprecedented. Analyzing the actions this city has implemented, together with the work experience on law, construction and system will easily harvest.

The mesoporous polyaniline (PANI)-TiO2composite microspheres were prepared by a facile hydrothermal method and characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area. The XRD pattern suggested that PANI did not modify the crystal structure of TiO2whereas PANI exhibited amorphous state. The SEM of PANI-TiO2displayed for microspheres. The gas sensitivity of the PANI-TiO2hybrid was also studied. The as-prepared sample was sensitivity to ammonia and ethanol and showed good reversibility. The PANI-TiO2hybrid material exhibits high sensitivity (0.96) to ammonia (150ppm) when operates at 373K.

Servo punch press uses a servo motor to drive. It can set different stroke length and velocity according to different production requirements, and can always ensure the formation precision of the bottom dead center. It has the advantages of high efficiency, high precision and low noise, and it presents the development trend of punch press. The key point of the servo punch press development is its control system. According to the functional requirements and technical performance of the servo punch press, the general approach of the servo punch press material forming control law is discussed in this paper. The development platform based on DSP control system has built up as well. By means of the Simulink and the Target for TI C2000 tools in Matlab, the dynamic model of punch press system and controlling model, including forming model, DSP-based controller model and plant model,etc., have been designed. Base on this, the forming characteristics of different materials, forming control algorithms have been studies through simulation and virtual experiments.The controller algorithm can be transferred automatically to the target controller. This approach can reduce developing time and costs of servo punch press control system and improve developing efficiency.

In vitriolic electrolyte, DC power supply is used on 7075 aluminum alloy to have anodic oxidation treatment then let the oxidized samples have a treatment of electroless plating. Surface morphology of the coating and performance of corrosion wear are studied by means of scanning electron microscope (SEM) and friction and wear experimental machine. The results show that unsealed oxide coating have many holes and cracks, which are extremely badly-distributed; corrosion resistance of the oxide coatings which have the treatment of electroless plating have improved, having lower coefficient of friction and better performance of corrosion wear; besides; coefficient of friction of the samples in water is higher than that in salt water, its wear amount is less.

UASB is used to treat chemical wastewater with high concentration organism. The successful starting of UASB is the taking shape of granular sludge. The operation of the project showed that：the consistence of CODcr was 3500 to 5000 mg/L in the influent, 1000 to 1200 mg/L in the effluent. UASB started-up successfully with the removal rate of CODcr was 80% and the system had stable operation.

In this paper, nano-copper/paraffin thermosensitive composite materials were prepared by high-energy ball milling, and pressed into the glass cylindrical tube by hot press molding. The micro-morphology and particle shape and microstructure of composite particles were observed by SEM, FI-IR, etc, the temperature sensibility of thermosensitive composite materials were tested by self-manufactured thermosensitive testing device. It shows that the way by which high-energy ball milling are prepared, the composite particle coated with good results, dense arrangement of particles, copper particles on the paraffin structure does not produce damage. With copper mass ratio increasing, the thermal conductivity of temperature sensitive composite is improved.

Whether the traditional ornament art or avant-garde ornament works, expresses the perception and thoughts of designer by Shapes and colors which assisted by a variety of materials. Along with the development of modern art, ornament art of personal image design starts the "modernization" revolution. Especially the applications of new materials and new technologies, have great impact on the designs of ornament, and also give scope to the development of the pattern of ornament. Modern ornament surmounts various limitations of technique and materials of traditional ones. The method of mordern ornaments innovate on account of the variety of materials. The new patterns attempt to combine and mix different materials, transform and process junk. All of the above increase new ideas of designs of ornament.

Jinjiu’s ceramic bottle has been in China’s wine market for a few years, and the choice of ceramics reflects traditional Chinese design idea of “combination of object and practicability, and manifestation of life with object”， which satisfies consumers’ requirements about national traits, style and taste of wine. This paper will analyze how Jiujin Group skillfully adopted China’s traditional ceramic technology to the design of package and explore a successful way of national package of wine through the example of Jiujin.

This paper introduces electroless plating Ni-Cr-P/Ni-P composite coating technologies and techniques on the Nd-Fe-B permanent magnet surface. It has got a Ni-Cr-P/Ni-P composite coating successfully on the Nd-Fe-B substrate surface through rational processing plan. The coating surfaces are bright and have low Porosity, good binding between the electroless plating and Nd-Fe-B matrix. The experimental results show that the composite coating prepared by Ni-Cr-P electroless plating (15min) and Ni-P acidic electroless plating (45min) has amorphous structure, simple process and better anticorrosion property in both alkaline and acidic medium.

Magnesium alloys are more and more researched and used as engineering materials in recent years. In the paper, the AZ91D casting magnesium alloy was as basic material by the proper chemical pre-treatment and then was coated with epoxy resin (EP) coatings modified with polyurethane (PU) for protection. The coatings’ adhesion strength, hardness, and corrosion resistance were studied by electronic universal tester, pencil scratch hardness tester, immersion test and electrochemical test. The effect of polyurethane addition on the properties of the coating was ales investigated. The results show that PU / EP ratio of 20% mass fraction can make the basic alloy good mechanical properties and excellent corrosion resistance. The interpenetrating network formed between the epoxy resin modified with polyurethane is of more excellent mechanical and corrosion resistance than pure epoxy resin to protect the magnesium alloy matrix.

The epoxy/polyurethane coating has high electrical isolation, anti-corrosion and high adhesive bond strength with magnesium alloy substrate. The coating can effectively block or reduce the substrate erosion induced by water, oxygen as well as the corrosive ions such as , and . The mechanism and efficiency of corrosion protection of the polyurethane coating and epoxy/polyurethane coating on magnesium alloys were studied experimentally. The results indicate that both kinds of coatings improved the anti-corrosion property of magnesium alloy evidently. The anti-corrosion property of the epoxy/polyurethane coating is better than that of the polyurethane coating. The experimental results, which were obtained by the immersion tests in 3.5wt% NaCl solution, loss weight tests, salt spray tests, adhesive force tests, hardness tests, electrochemical tests and stereo microscope photos, definitely support the previous conclusions.

The main causes of segment failure of diamond saw blade are studied in this paper. The segment material, the microstructure and the wear resistance of saw blade material were studied with scan electronic microscope, energy disperse spectroscopy, hardness meter, optical microscope. The results shows that the addition of alloying elements could refine grains, improve the holding force of matrix to diamond, enhance wear resistance of matrix to diamond, and decrease wear coefficient about 20%.

Magnesium Alloys are of low density, high specific strength and high strength, leading to much application prospect in industry and civilian use. However, the alloys are restrictedly used because of easy corrosion. In this paper, The Organic coatings on Magnesium Alloys are made. The electrochemical properties of organic coatings are researched by scanning electron microscope (SEM), stereoscopic microscope and electric-chemistry Work station. The research results show that the curves of open-circuit current to time and Tafel polarization shuffle more for the Pu and ER/PU coatings than for base alloy. With addition of the coating, the magnesium alloy has much low corrosion current density (icorr) and high polarization resistance (Rp), and then its Anti-corrosion Property is evidently improved.

The wear behavior of chromizing-titanizing coating is examined in different media at room temperature and at elevated temperature, and compared with the wear behaviors of chromizing coating, titamizing coating and basis carbon steel. The structure of chromizing-titanizing coating is analyzed using electron probe, X-ray diffration and hardness. The results show that the chromizing-titanizing coating has better wear resistance than that of chromizing coating, titanizing coating and basis material. The wear resistance of chromizing-titanizing coating is mainly affected by the microstructure and composite of the coating which consists of complex compounds containing chromium carbides and TiC. The chromizing carbides exist mainly outside the coating and TiC exists mainly inside the coating. The complex compounds make the coating have both advantages of chromizing coating and titanizing coating, resulting in good wear resistance of chromizing-titanizing coating at room temperature and at elevated temperature.