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However, dispersion of carbon nanotubes in polymeric matrices is a critical issue since improper nanotube dispersion can adversely affect the mechanical properties of composites.
The fractional change in resistance (∆R/ R) and average gauge factors of braided composites are provided in Table 2.
The calculated gauge factors are also indicated.
Moreover, the gauge factors are higher in case of lower concentration of chopped fibres.
Gauge factors up to 23.4 were achieved at very low level of cyclic flexural strain (0.55%).

Analysis on Measuring Circuit of Pressure Difference Sensor with Magnetic Fluid Rui-can HAOa, Hua-gang LIUb, Wen GONGc and Jin-ru MA School of Mechanical Engineering, Beijing Polytechnic, Beijing 100176, China ahaoruican@163.com, bliuhuagang999@126.com, cgongwen119@yahoo.com.cn *Rui-can HAO Keywords: measuring circuit; pressure difference; sensor Abstract.
Due to many sensing properties, magnetic fluid is used in a novel application--sensor.
The power frequency and the input voltage are the two important factors for the measuring circuit.
Introduction Magnetic fluid has many properties such as fluidity, magnetism, buoyancy principle, and so on.
Determination of Power Frequency The power frequency affects the output voltage of the circuit directly, so the selection of the power frequency determines the sensitivity of the pressure difference sensor with magnetic fluid.

These properties are highly affected by the phenomenon of ageing.
The shift factors were modeled using the WLF equation as shown in Fig. 4 and the fit is almost perfect with an RMSE of only 0.0118.
Shift factors for the 35-50 unaged asphalt Table 2.
Ferry, Mechanical properties of substances of high molecular weight in amorphous polymers and other glass-forming liquids, Journal of American Chemical Society, 77(19), (1995), 3701-3707
Isacsson, Influence of commercial waxes on bitumen aging properties.

Introduction Due to the difference of diagenesis time, rock mineral composition and the geological structure in coal measures strata, strata thickness and mechanical properties are different.
It trigger dynamic disaster of the mine, and seriously affected the safety production of the work surface and even the mining area.
Rockburst is a common dynamic phenomenon ofcoal and rock in coal mining.Because of the influence of mining method, the fault structure and other factors, coal mining generally has two sides, three sides , surrounded mined gob and various forms of isolated island working face.
Hard roof become main factor occurred rock burst in isolated working face [7-10].
Physical and mechanical parameters of coal and rock mass use geological data and the results of rock mechanics test.

Radiation damages and different modified properties have been observed, not only on the treated surface and near-surface layer but also at a depth of hundreds of micrometers.
showed that the presence of defects in the sub-surface layer is the main cause of the improved properties of metals.[4-6] Therefore, a full appreciation of the thermodynamic process and related modification mechanism of HCPEB bombardments should be reexamined and more detailed thermal stress models should be developed.
The temperature and stress fields are the main factors that determine the structural state and properties of the beam-affected zone.[8-10] If the substrate is not melted (either before melting or due to insufficient beam energy density), there should be two kinds of stress fields induced by the bombardment, a thermoelastic stress σx and a quasi-static thermal stress σy, as shown in Figure 1a.
(a) (b) (c) Small droplet P Eruption P Zone affected by thermoelastic stress wave Heat-affected zone quasi-static thermal stress σy σx electron beam Fig.1.
Thus the significant enhancements of the mechanical and tribological properties observed at depths of hundreds of micrometers are clearly due to the thermal stress impacts.

Therefore, any possibility affording estimation of mechanical performance of a muscle, as an adaptive subsystem, is a matter of utmost importance.
The occurrence of fatigue within the muscle is usually stipulated by a majority of external and internal factors.
The relationship of maximum biosignal level 2Amax and loading duration under constant load in a) male and b) female age groups, 1 - F = 12 N, 2 - F = 18 N In reference [4] the analysis into the muscle's performance under constant force conditions has led to the generation of the following relationship applicable to biosignal energy: ∫= t dt R )t(U F )t(x 0 2 1 , when const)t(R = , ∫= t dt)t(U FR )t(x 0 21 , (1) where F is the force affecting the muscle ( const=F ); R stands for resistance of the muscle, U(t) is muscle biosignal intensity and t represents duration of the muscle loading.
Reich: When Active Muscle Lengthen: properties and consequences of eccentric contractions (News of Physiology Science, Vol. 16, 2001), p. 256 - 261 [3] M.
Milner: Muscle-Tendon Mechanical Impedance http://www.sfu.ca/~tmilner/aclb3.pdf [10] L.

In addition, the mechanical properties of these samples are tested to evaluate their efficiency and effectiveness in the paving layers.
For estimation of the CBR values of soil, many models were created depending on many factors.
Roy [13] developed a prediction model to find CBR values by studying the soil properties.
As a result of non-plastic behaviour for most soils, there was no correlation between the mechanical properties and the CBR values.
· The regression models revealed the strong impact of these properties on CBR values.

The influences of some basic factors such as the running speed, the axial preload, the oil viscidity, the design contact angle of bearing, and the ball materials and so on are analyzed on the heating performances in a bearing.
Because the affects are very small, it cannot be taken into account of the friction heating between the retainer and the rings, and so the air friction heating is.
It can be known that the materials with different properties such as the mass density, the elastic modulus and Poisson-ratio, will affect the inertial loads of the ball element, the contact stress and contact deformation between balls and both ring raceways, and will also affect the heating performances inside EHL films in the contact areas.
Zhang: Mechanical Engineer, Vol. 12 (2005), pp. 110-111 (in Chinese)
Li: Mechanical Engineer, Vol. 4 (2004), pp. 12-14 (in Chinese)

Compared with Mg based alloys, pure iron and its alloy possess better mechanical properties and don't have troubleshotings with H evolution during the degradation.
The metallic affected layer is very thin with a height less than 100 nm based on a generalized surface corrosion with no pitting signs.
It's composed of martensite and austenite phase at room temperature and exhibits better mechanical properties than pure iron.
Xu, HY.Chen, Microstructure, mechanical properties and bio-corrosion properties of Mg–Si(–Ca, Zn) alloy for biomedical application, Acta Biomater, 6 (2010) 1756–1762
Lohan, Factors Influencing the Reversion of Stress-induced Martensite to Austenite in a Fe-Mn-Si-Cr-Ni Shape Memory Alloy, J. of Mater.

In doing so, amplitude of stress intensity factor vary in the range of 20 – 35 MPaÖm.
This causes the accumulation of structural and mechanical damages in the material, formation of corrosion and mechanical micro-defects that are potential sites of fatigue crack nucleation and growth [2].
In addition, the changing of structure and properties under the operation increases the risk of unpredictable failure, so it is necessary to establish the relationship between the statistical characteristics of the material and the mechanisms of its fracture [3].
Thus, it practically does not affect the mechanism of its propagation.
Proceedings of the Institution of Mechanical Engineers, Part F: J.