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Propagation characteristics of Ultrasonic wave in the pipe wall and its simulation analysis 3.1 Propagation characteristics of Ultrasonic wave in the pipe wall The speed of ultrasonic wave in an infinite solid medium is only related to material mechanical properties.
We need to consider some influence factors such as interface sound emission coefficient, energy emission coefficient and attenuation coefficient, when establish the mathematical propagation model of the ultrasonic wave in solid medium
The stress field: （4） The reflection coefficient and refraction coefficient: （5） From formula (5) we can conclude that, in practical application, frequency of the transducer excitation signal at the frequency pass band is not constant, so when the difference of acoustic impedance of materials at two sides is not significant, the final output of the ultrasonic transmission curve bump will be not obvious, and this situation will Affect the accuracy of thickness measurement.
(2) Due to the occurrence of transmission and transmission, the thickness measurement is related to material properties, acoustic attenuation coefficient, interface sound pressure emission coefficient and emission coefficient of energy.

Computations of Transient Flows and Sprays of Port Fuel Injector Yin congbo1, a, Zhang Zhendong1,b, Guo Hui2,c and Cheng Qiang1 1College of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China 2College of Automobile Engineering, Shanghai University of Engineering Science, Shanghai 201620, China aemailyincong@tom.com, bzzhend@hotmail.com, c ghguohui@yahoo.com Keywords: Transient Flow; Port Fuel Injector; Spray; CFD simulation Abstract.
Port fuel injection requires that the injection time may be very short in duration, indicating that transient flow effects can have a strong influence on the flow behavior and on the spray properties.
The working liquid physical properties are close to the values of a standard gasoline (density: 785 kgm-3, viscosity:　9.410E-4 Nsm-2).
The level of inject pressure will affect the momentum of the spray.
Influencing Factors on Open Process of an Electronic Fuel Injector [J].

The maximum strength was not affected by the repair method used, but the yield load was greater when the specimens were repaired with epoxy mortar.
For the Series 1 specimens, however, the index value was multiplied by a reduction factor (α= 1/2) in view of the fact that stresses at the time of sheet detachment were about 1/2 of the material strength.
Pt×σy = Pst×σsy + Pcf×σcf×α (1) Pcal = 2M/L, M = (0.9×at×σsy×ds) ＋(0.9×af×Ef/Es×σcf×α×D) (2) where, Pst: tension reinforcement ratio, σsy : yield stress of steel, Pcf = Acf/BD, B: width of beam Acf: cross-sectional area of CFS, D: depth of beam, σcf: tensile strength of CFS L: shear span length, at: cross-sectional area of steel, af: cross-sectional area of CFS ds:effective depth of beam, α: reduction factor Fig. 5 The amount of reinforcement and maximum load Fig. 6 Comparison of measured and calculated values Outline of finite element analysis.
The strength of the corroded specimens decreased because of spalling of concrete, loss of bond, and deterioration of rebars' mechanical properties due to corrosion-induced cracking.
Noguchi, Evaluation of the bond properties between concrete and reinforcement as a function of the degree of reinforcement corrosion, Cement and Concrete Research, 2002;(32):1313-18

The three factors that have a major impact on this process are the complexity, differentiation and timeliness, indicating that the application of new materials and technologies is simpler, similar to the application method of traditional materials and technologies and can be learned and mastered by architects in a short time.
In the modern construction system, the architects and structural engineers are one of the most important affecting factors.
According to the system theory, the integrity, diversity, relevance, hierarchy and constitutive property are the common basic features of all systems.
As the active users of architectural materials and technologies, architects and structural engineers are always the key decision-making and influencing factors in construction system.
In the early days, concrete was used in architecture because it has similar mechanical properties with the stone has.

Formation of Nano-Scale FeCO3 Protective Corrosion Product in Carbon Dioxide-Saturated 3% Sodium Chloride Solution Saeid Kakooei *1a, Mokhtar Che Ismail 2, Bothi Raja 3, Hamed Mohebbi4, Seyed Sattar Emamian5, Majid Moayedfar6 1-4Centre for Corrosion Research, Department of Mechanical Engineering, Universiti Teknologi PETRONAS, Tron-oh31750, Malaysia 5-6Department of Mechanical Engineering, Universiti Teknologi PETRONAS, Tronoh31750, Malaysia askakooei59@hotmail.com Keywords: CO2 Corrosion, Carbon Steel, Nano-scale, FeCO3 Abstract: Corrosion of carbon steel in CO2 saturated NaCl solution contains the formation of FeCO3, as a corrosion product.
The protective property of the formed FeCO3 scale layer to corrosion in brine solutions containing CO2 was established as the possible cause of the corrosion rate decrease above 60 oC.
Precipitation of FeCO3 can be affected by two variable significant factors: temperature and pH [7-8].
Based on environment condition, FeCO3 film can be deposited in nano-scale which has more effective protection property.

Due to the wide-spreading saline soil in Xinjiang region, the highways at saline soil sections often suffer from salt heaving, frost boiling, leaching, saturated yielding and other hazards in this region, resulting in net-shaped pavement cracking, deformation and swelling and the like and consequently affecting the normal highway transportation.
Its mechanical property will also change accordingly.
These disasters not only affect the normal transportation, but also result in a huge economic loss. 1.2.1 Dissolved collapse deformation Due to the increase in water content or temperature, the salt in soil is dissolved and taken away by water, resulting in gradual loss of the soil strength.
Under the action of traveling vehicles, local pavement will swell and crack and mud will come up, resulting in muddy and slippery road surface and affecting the normal traveling of vehicles.
In the practical engineering, it is required to consider major influencing factors and seek for reasonable and effective treatment measures by combining the hydrogeololgy, climate and construction conditions; meanwhile, it is also required to combine the in-site actual situation to flexibly utilize the existing treatment measures and explore new treatment methods on this basis, so as to improve the saline soil treatment.

Introduction The blades are one of the most expensive components of a wind turbine and their mass affects parameters and cost of the other components (hub, nacelle and tower).
Therefore, too large safety factors are applied in calculations of strength of the blade which leads to its weight increase.
Designed ply material properties necessary as input data in ANSYS Workbench Material parameters EX [GPa] EY [GPa] Ez [GPa] υxy υyz υxz Gxy [GPa] Gyz [GPa] Gxz [GPa] UTS-L* [MPa] UCS-L* [MPa] Thickness [mm] Lay-up Material UD600[0]2 40 15.9 15.9 0.29 0.29 0.29 4.7 3.5 4.7 629 -530 1 WR300[±45]4 15 15 8 0.3 0.3 0.3 4.7 2.7 2.7 144 -215 1 *UTS-L, UCS-L - Ultimate longitudinal tensile and compressive strength.
Mandell Mechanical Properties of Composite Materials for Wind Turbine Blades, Composite Material Fatigue Database, Version 22.0; June 25, (2013), Montana State University, available at http://www.coe.montana.edu/composites, accessed: 17.09.2013
Bere, Mechanical characteristics of composite materials obtained by different technologies, Academic Journal of Manufacturing Engineering. 4 (2011) 100-105

Li1,2,d,* 1Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China 2Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China aclt07@mails.tsinghua.edu.cn, bhuawei.zhang@gmail.com, cyuanliu@tsinghua.edu.cn dyanxiang@tsinghua.edu.cn (Y.
temperature independent fluid properties, (6).
constant solid properties.
The experimental results and simulation results both show that porous copper heat sink has excellent heat transfer performance, which was deeply affected by area ratio of penetrating pores.
Besides, the structural parameters of porous copper are the important factors which influence the heat transfer performance of heat sink.

All the current CPCs are reported to have good mechanical properties and reasonable setting times.
All the current CPCs are reported to have good mechanical properties and reasonable setting times.
During membrane-promoted bone formation, membrane porosity has been found to be of importance for the initial rate of bone formation as well as for the performance of the material in the tissue, although the final amount of bone seems not to be affected [12].
Growth factors and bone regeneration.

The difference in cationic field strength of individual rare-earth might result in different grain boundary phase properties and microstructure development [4,5].
The present work deals with the investigation of nano-mechanical properties (nano-hardness, modulus) and macro-hardness of SiC and Si3N4/SiC composites.
The samples were hot pressed at 1850 °C/1h (SiC) or at 1750 °C/2h (Si3N4) under mechanical pressure of 30 MPa in Ar+N2 (SiC) or N2 (Si3N4) atmosphere, respectively.
It was already published that the measured nano-hardness is only partially affected by grain boundary chemistry [9].
The reason for lower macro-hardness is the influence of several factors like triple pockets, porosity, grain size, indentation size effect, etc., but mainly the grain boundary phase composition in polycrystalline materials.