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The direct difference method is used for solving the heat conduction equation, and simulate the solidification process of T-type cast. The effect of the thermal resistance at cast/mold on distribution of temperature and the solidification rate of corner region is studied. The results show that during the solidification process of T-type, the riser region first solidified, followed by the right half, finally the solidified part was around the corner. With the decrease of the thermal resistance at cast/mold, the temperature of the corner area decreased more quickly and the solidification rate increased. In the actual design process, the material with the good thermal conductivity should be selected for the cast mold to accelerate the solidification rate of the corner region, so the solidification rate of the corner and riser region tend towards harmony, which reducing the formation of various types of defects, and the quality and mechanical properties of the casts were improved.

In this paper, through the analysis of the Bohai seabed pipeline’s leaking characteristics in delivering, temporal and spatial distribution model of seabed pipeline spilt oil’s floating is built. The model is combined with the Bohai Sea’s hydrodynamic characteristics and the water’s condition, and assumes that spilt oil is a unit of particle. With this model, spilt oil’s floating trajectory and its characteristics can be simulated after a seabed pipeline oil spill. The time spilt oil floats to the surface and the trajectory distribution can also be calculated.

The surface composite layer Ni/ZrO2 on the ZG45 cast steel surface was fabricated through vacuum infiltration casting method. This paper researched on the Ni/ZrO2 composite infiltrated layer morphology, hardness and the friction property under fry friction. The results show that the main phase structure of the layer is ZrO2, Cr2B, NiB and FeNi. The macrohardness of the layer is HRC60~64. The micohardness presents gradient change. The maximum hardness appears at subsuface. The 10% ZrO2 composite infiltrated layer wear resistance increases 10 times and 15% ZrO2 composite infiltrated layer increases 22.6 times than ZG45 under the 100N load. The 10% ZrO2 composite infiltrated layer wear resistance increases 8.5 times and 15% ZrO2 composite infiltrated layer increases 21.9 times under 250N load. The wear resistance has greatly improved.

For the importance of automobile light and hard to design problem, the application of high level injection tooling Moldflow was used. Through analyzed with Moldflow and combined the actually mold tooling developed experience, the lens of the automobile light developed successfully. The results show that the mold injection gate position and Hot-runner type are quite reasonable. The designed sub-runner and injection process parameter are suitable. There are no air traps and weld line with this mold to produce the auto light lens. The shrinkage of the product is even and the maximum shrinkage value is below 4% that fulfill the plastic demand. Using the Moldflow can reduce the development cycle, the experiment time and improve the product quality and working efficiency.

This paper analyses the basic structure and the separation theory of hydrocyclone. Three-dimension spiral flow theory and CFD method was used to simulate the Φ75mm hydrocyclone. The paper focuses on researching the separation efficiency influenced by different inlet velocities, volume fraction values and the particle diameters. Besides, the influence of the thickness of overflow pipe is also considered. Results of numerical simulation shows that with the inlet velocity range from 1 to 5m/s and the particle diameters range from 2 to 5um, the hydrocyclone separation efficiency is increasing. As the volume fraction value increased from 1% to 15%, the separation efficiency descended. Increasing the thickness of overflow pipe can reduce the turbulent kinetic energy of hydrocyclone, which can make the inner flow field more stable and enhance the separation efficiency.

Taiwan is a small island. Some of college campuses are very tiny with large hard pavement to cause un-comfortable outdoor environment. Most of faculty and students like to stay at classroom and use air-conditioner to establish comfort thermal environment. Thus, the outdoor and semi-outdoor thermal equipments are used to detect the parameters of weather. The test and analysis results show that hard pavements cause the un-comfortable outdoor comfort. Mean Radiant Temperatures of grass in summer is higher than the other pavement because that grass pavement is lack of moisture to causes bad outdoor thermal comfort. Therefore, the fine outdoor and semi-outdoor thermal comfort environment should consider the permeable pavement and grass with suitable moisture to cause better outdoor thermal environment and large arbores should be planted widely in campus to establish a better semi-outdoor thermal temperature in campus of the subtropical zone.

It is of great importance in classifying reservoirs and establishing the relationship of pore structure and productivity for formation evaluation and reserves estimation. In this study, based on the morphological characteristics and the difference of pore structure evaluation parameters acquired from mercury injection capillary pressure (MICP) data, which were obtained from the experimental results of 20 core samples drilled from Chang 6 tight sandstone Formation of north Ordos basin, the Chang 6 formation is classified into three types, and the corresponding average MICP curves of every types are obtained. These were usable in determining the potential target formation and predicting the productivity in tight sandstone reservoirs.

The transparent glass-ceramics containing nanocrystalline AlNbO4 phase in the 25Al2O3-27Nb2O5-40SiO2-7Na2O-2Eu2O3(wt%) glass were prepared by the melt-quench technique followed by a two-stage controlled heat treatment. Crystalline phase were indentified using X-ray diffraction (XRD) which AlNbO4 phase was found. Scanning electron microscopy (SEM) was used to image the crystalline phase morphologies. The luminescence spectra of Eu3+-doped glass and glass-ceramics were recorded at 393 nm exciation wavelength and the luminescence intensity is found to be increase with heat-treatment time due to increase in crystallinity. The high intensity ratio of 5D0-7F2 to 5D0-7F1 indicates that the Eu3+-doped nanocrystalline AlNbO4 glass-ceramics are promising candidate materials as red-light source.

Er3+-Yb3+ co-doped ZnO-B2O3- SiO2-TiO2 transparent glass ceramics were synthesized by melt crystallization technique. Samples were characterized by DSC, XRD, SEM, UV-Vis-NIR and fluorescence spectra and the factors affecting the crystallization of glass ceramics were analyzed. The results indicated good crystallization property of ZBS glass ceramics. The optimum crystallization temperature was 800°C, and crystallization time was 60 min. The main crystal phase was Zn2TiO4 and the transmittance was up to 70% in visible light region. SEM micrograph indicated that the grain diameter was less than 100nm and the emission spectrum of glass ceramics displayed by fluorescence spectra was greatly improved compared with matrix glass. Strong emission peak was observed at 1535nm.

Porosity and permeability are two important input parameters in formation evaluation. However, It faces a great challenge for formation porosity and permeability estimation in tight sandstone reservoirs in the Ordos basin of northwest China due to the greater contribution of rock matrix and complicated pore structure. In this paper, based on the analysis of conventional log responses and 324 core samples drilled from the target formations in different wells, the estimation models of reservoir porosity and permeability are established, and the reliability of these models are verified by comparing the calculated porosity and permeability by using the established models with core analyzed results. The absolute errors between these two kinds of porosities are all lower than 0.64%, and the relative errors between them are lower than 7.1%, these are coincided with the requirement of reserve estimation.

On the basis of experimental verification, the optimum processing conditions of CaO-B2O3-SiO2(CBS) system transparent glass-ceramics were obtained. Composition of main raw powders (wt%) was:CaO 38%,SiO240%,B2O312%.The precursor glass was prepared by melting method and annealed at 560°C for 2h and cooled to room temperature at a speed of 5°C/min.The best nucleating agent is P2O5. The appropriate heat treatment regime to precursor glass was determined to be 2h at 600°C for nucleation and 3h at 780°C for crystallizition.Under this condition,the transmittion of glass-ceramics at the range of visable light is 72% in average and Sm3+keep good luminescence property doped in this host material.

Partial coherence analysis can eliminate competing influences of different noise sources and identify the main noise source when all noise sources of system are relevant. In the paper, the method of partial coherence analysis is used for identifying noise source of grader. A multi-input and multi-output noise source identification model is established. And then the computational formula is developed. Finally, an experiment is carried out with an actual grader. In the experiment the main noise sources are accurately identified.

Based on the internal structure of a small self-propelled mower, extract key points and make the main outlines of the machine by connecting the points in four ways: straight lines connect, arcs connect, free curves connect and data fitting. Then start from the main outlines and make the morphological evolution by the rules of "tilt", "fillet" and the characteristic of curves to obtain lots of basic shapes of the machines. Choose and modify the shapes by a unified style to get the final design of the mower. The period of the R&D of the small self-propelled mower is shorten and the final design is simple and effective in line with the appearance needs of such kind of products. Moreover the final shells of the mower are better match with the structural components. That verifies the feasibility of the design method and its better effect.

In this paper, the wind power generation monitoring system hardware research, design a real-time monitoring the operation of the air handling unit, based on wireless sensor network. Use of wireless sensor networks to collect relevant data, data analysis and processing of the MCU as the core components, combined with a GSM module, Zigbee module for wireless transmission of data to achieve the purpose of real-time monitoring.

The influence of air content on compressive strength of C20，C30，C40 and C50 concrete was investigated in this paper. The result shows that this relationship varied with concrete strength grade. For C20~C40 concrete, the air content increases with addition of air entraining agent, while a maximum air content value appears for C50 concrete. The compressive strength of C20 decrease slightly with the air content, on the other hand, that of C40 significantly decreases relatively.

Combined Cooling，Heating and Power system(CCHP system) has potential advantages in areas of energy reliability, environment and economics. This paper analyses the system's principles and puts forward internal combustion engine CCHP system and builds a series of mathematical models of each part. The main purpose of this paper is the analysis of the annual total cost and energy saving rate, the results show that, compared with the conventional supply system, the CCHP system can save 1,060,000￥annual, the save rate is amounted to 22.1% and relative energy saving ratio could reach 13%. This study may provide with some reliable foundations on the application of the CCHP system.

A new kind of bainite steel with ultra-low carbon content and Nb, Ti alloys has been developed. By applying thermomechanical control process, water quenching and tempering at different temperature, excellent properties have been obtained when tempered at 450°C, with the yield strength of 813MPa and elongation of 16.2%. The morphology observed by SEM shows that the microstructure consists of fine lath-shaped bainite, polygonal ferrite, quasi-polygonal ferrite and a small fraction of residual austenite or martensite-austenite constituents. In a TEM study plenty of precipitates with the size about 5-10nm were observed interacting with the dislocations, which is very significant for the optimization of strength and ductility.

Large amounts of polychlorinated dibenzo-p-dioxin and furans (PCDD/F), polychlorinated biphenyls (PCB) and polychlorinated benzenes (PCBz) were formed by de novo synthesis using model ashes. The de novo synthesis was affected by SO2 and H2O. Knowledge of congener pattern and homologue profiles of PCDD/F, PCB and PCBz is help for elaborating the mechanism of formation and influence of the toxic compounds formed by de novo synthesis. By the help of the component analysis (CA) the best correlated congeners are effectively detected. Various good correlated pairs between PCDD/F, PCB and PCBz have been elaborated by using linear regression between the 15 samples. It was found that a good correlation between PCBz and PCDF.

At present, many experts and scholars use theory way to search the concrete’s dry shrinking stress. According to action and in-action principle, the writer designed one experiment model indoor to test the concrete’s stress variety in construction stage by the stress and strain apparatus. In this experiment, successfully collected the data of the stress variety with the time in 0~24 hours of concrete plank-placing in unit width. Through analysis the data, discover the regulation that dry shrinking cause crack in concrete’s construction stage.

Naval airport aerial equipment support leads a vital status in aerial equipment support, a key point to support airport aerial equipment is the warehouse, but most existents are single and fixed, survival risk of the warehouse becomes an important threat to combat ability of airplane. Aimed at reducing risk of naval airport aerial equipment warehouse in wartime, a distributed system was given to optimize the naval airport aerial equipment storage solution. This system effects not only on reducing risks in wartime equipments supply, but also on equipment transferring support. Based on analysis of the necessity and feasibility of distributed storage, this paper introduce structure and operation process of the system in detail, and some constructive suggestion was given to naval airport aerial equipments storage.

In hard plastic extruding course, the frictional resistance among particles and between the particles and mould make the extruding pressure 4 to 20 times larger than soft-plastic extruding. This paper study the plasticizer mechanism of water-soluble plasticizer in hard plastic extruding course, and emphasize that in this course the plasticizer liquid film not only have good combination with ceramic particle, but also has high yield strength so that the plasticizer liquid film is difficult to slide and be pulled thin. The compound usage of different plasticizers which can improve the effect of plasticizer enhances the quality of the final molding body.

A modified cellular automaton model was proposed to simulate the dendrite growth of alloy. Different from previous models, this model used neither an analytical equation(such as KGT model) nor an interface solute gradient equation to solve the velocity of solid-liquid interface, but used the interface solute and energy conservation and thermodynamic equilibrium condition to describe the solid/liquid interface growth kinetics process. In present model, once the temperature field and solute field were solved by finite different method in the entire domain, the material thermodynamic properties can be substituted into four algebraic equations to easily determine the variation of solid fraction, interface temperature and solute concentration, instead of calculating interface moving velocity. As a result, the complexity of the calculation can be largely reduced. The simulated dendrite growth was in a good agreement with the Lipton–Glicksman–Kurz (LGK) model for free dendritic growth in undercooled melts.