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Since layup orientation of the laminates greatly influences its properties, an NDE technique for layup orientation determination would be very beneficial.
One of important factors is the layup sequence, which can greatly influence the CFRP composite performance.
The model is general and applies to any layup produced from plies with orthogonal properties.
The first assumption used is that the interface and beam spreading losses are negligible, that is, all signal reduction factors are equal to one.
It is thought that the fiber direction of CFRP laminates affected to shear wave ultrasonic signals.

These defects significantly affect the physico-mechanical properties of the materials and result in local disorder features of the stress distribution if loaded.
Consequently, direct simulation of the randomness of disordered material microstructure is useful in reaching to a better understanding of brittle failure and the improved predication of the physico- mechanical properties.
However, in most of the cases, analytical models have to be simplified and sometimes this simplification ignores very important factors influencing the material behavior.
According to the Weibull distribution and the definition of homogeneity index, a larger m implies that more elements with the mechanical properties approximated to the mean value and a more homogeneous disordered media.
The mechanical properties for the two specimens are listed in Table 1.

These parameters mainly depend on the diameter, wall thickness and material type of a tube; sometimes, they also depend on the chemical composition and mechanical properties of the material.
Sometimes, owing to the differences between the chemical composition and mechanical properties of the material used, technological parameters must be changed.
The material of the billet was assigned the properties of 13CrMo4-5 steel.
In addition, 13CrMo4-5 steel has a good workability, both in hot and cold deformation, as well as good machining properties.
[8] Alloyed steel with specified elevated temperature properties.

While compaction of the powder defines the shape, sintering defines the microstructure, frequently the porosity and in general the mechanical and functional properties of the product.
Berner et al. [29] have shown very early that also the C content affects the copper swelling, lowering the expansion by adversely affecting the wetting of solid Fe© by the Cu melt.
If this is however granted, transient liquid phase can be highly effective towards the mechanical properties.
However, microstructures with defined inhomogeneity may be better for the mechanical properties, as is well known e.g. from Ni-Cu-Mo alloyed variants [26].
Danninger, Sintering of Mo alloyed P/M steels prepared from elemental powders, I: Sintering temperature and mechanical properties, Powder Metall.

Higher concentration of NaOH is of advantage to the mechanical property development of the fly ash based cementitious material [[] A.
In light of the former study, the activity of fly ash plays an important role in the reaction of AAFA and contributes to the final properties of the mortars [[] A.
Results and discussion Effect factors on the dissolving of active Si/Al Fig. 1. shows the variation of active Si/Al dissolving percentage from fly ash activated with different concentration of NaOH solutions.
SEM pictures of fly ash particles activated by NaOH solution Conclusions The dissolving percentage of active components from fly ash depends on the chemical and physical properties of the initial fly ash.
The factors effects on the potential reactivity of fly ash are the concentration of alkali activator, the content of the vitreous phase and the particle size distribution of the flay ash.

Silica crucibles has unique properties such as high temperature performance, good mechanical strength, exceptional resistance to thermal shock, thermal and electrical insulation and chemical stability [1].
The results of the sensitivity analysis and the respective weighting factors are shown in Figure 3 Fig. 3 Sensitivity analysis of the impact of the monitored parameters on MOR.
It appears, therefore, that the dominant variables that affect the overall strength of the tested specimens are porosity and d10%.
The sum of the weights (sensitivity) factors of all analyzed variables is 735, while the two most influential variables (porosity and d10%) have a summary weighting factor of 620.

Fig.5 Photo of ELID grinding experimental device 1-Centre height fine-tuning device 2-workpiece 3-vacuum chuck 4-Vertical (Z coordinates) servo motor 5-Control Unit 6-Micro-displacement detection device 7-Vibration isolation devices 8-Horizontal (X coordinates) servo motor Fig.6 ELID grinding experimental device schematic Table 2 ELID grinding conditions Voltage duty cycle Frequency Spindle speed Workpiece speed Feed rate 120V 65% 60kHz 700r/min 700r/min 1µm/s Table 3 ELID grinding conditions coolant grinding wheel graininess Wheel diameter Wheel speed Feed depth Dedicated grinding fluid W10 10mm 80000r/min 1µm Experimental Results and Analysis of Influence Factors Measuring Results of Spherical Error of Concave Spherical Surfaces and Analysis of Influence Factors.
The reason of error forming of spherical surface is that: Firstly, the machining accuracy of transition disk itself is not enough to ensure the position accuracy of axle holes, and coaxiality error of the axle holes is one of the important factors affect on the accuracy of spherical accuracy.
(a) spherical surface after ELID Ⅲ grinding (b) spherical surface after ELIDⅡ grinding Fig.7 Measuring results of spherical surface Measuring Results of Surface Roughness of Concave Spherical Surfaces and Analysis of Influencing Factors.
Liu: China Mechanical Engineering, Vol. 10 (1999) No.5, pp.570-576.
Yang: Mechanical Workers, Vol. 11 (2003), No.9, pp.44-45.

Power harvesting in a diaphragm depends on several factors.
Especially, the temperature-dependent material properties are not accounted for.
The interest here is in determining the factors that lead to maximum electrical energy generation.
The physical properties of the brass substrate and the PZT ceramic (PZT-5A) are: 110mE = GPa, 8290mρ = kg/m3, ν=0.374, cρ =7750 kg/m3, σ=0.33, 11 D s =14.4×10-12 m 2/N, T 33ε =1.5×10-8 C2/Nm2, 31d =-171×10-12 C/N, 2α =0.9×10-6 oC-1.
Some interesting aspects that affect the output power are discussed.

Both the mechanical resonance and the tensile testing are methods used to study the mechanical properties of nanostructures.
The resonance method has been used to study the mechanical properties of one-dimensional nanostructures such as carbon nanotubes, nanowires and nanobelts [1-5].
During the tensile test the presence of a nanocrack is expected to strongly affect the failure stress.
Eq. (1) gives basically the definition of the "equivalent" homogeneous properties AIEb ρ, and allows us to determine the true boron Young's modulus BE (by characterization of the oxide B2O3 layer).
The quality factors measured inside the SEM vacuum chamber (at a pressure of 10 -6-10 -7 Torr) ranged between 300 and 1000.

Studies on the protection of aircraft oil tank’s microbic erosion based on properties of machinery and biological materials WEI Zhenga, WANG Fang Chaob ,WANG Yuan Shengc , YU Hong Weid,* Naval University of Engineering, Wuhan, China azhengweihjgc@126.com, bwfch1992@163.com, csklpmeysw@scu.edu.cn, dxgq1967@vip.sina.com * Corresponding author:Yu Hong Wei, E-mail: xgq1967@vip.sina.com.
In addition to these necessary conditions of water and hydrocarbons, many other factors, such as nitrogen, oxygen, phosphorus, sulfur and other elements are also provided the conditions for microbial growth in the fuel system.
Outlook As special supplies, aviation fuel are widely used in the field of military and civilian, affecting its quality and merits of the aircraft's self-evident.
Hebei University of Science and Technology, 2010,31 (3): 270--273 [10] Xia Zhi new hydraulic system contamination control [M] Beijing: Mechanical Industry Press, 1992: 10-15