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Carbon nanotubes (CNTs) had high electrical conductivity, high aspect ratio, low density and super mechanical strength, and was compatible with polymer matrices.
Comparing curve b and c, we found that FT-IR of the composites was almost same as that of LDPE, which indicated that s-MWNTs didn't affected the chemical structure of LDPE.
Electrical property DC volume resistivities(ρDC) of three sets composites at room temperature were shown in Fig.6.
Log-log plots ofσto (p-pc) Table 1 Percolation thresholds, critical exponents and correlation factors for the three sets of MWNTs/LDPE composites composites Percolation thresholds[%], pc Critical exponent (t) Correlation factor (R) p-MWNTs/LDPE 0.20 4.58 0.999 a-MWNTs/LDPE 0.20 4.17 0.999 s-MWNTs/LDPE 0.10 1.65 0.990 4.
Conclusion We fabricated three sets of composites by melt processing technique and investigated their structures and electrical property.

The conclusion is that the apparent activation energy E value is key factor in the equivalent age method, larger value of E indicated that the age conversion factor versus temperature function is more nonlinear, and an increase in temperature results in a disproportionate increase in the age conversion factor.
It has been showed that several factors influence the experimental activation energy: water–cement ratio (w/c); curing temperature; degree of hydration; cement composition and the use of mineral admixtures.
In a word, larger value of E indicated that the age conversion factor versus temperature function is more nonlinear, and an increase in temperature results in a disproportionate increase in the age conversion factor.
Larger value of E indicated that the age conversion factor versus temperature function is more nonlinear, and an increase in temperature results in a disproportionate increase in the age conversion factor
Effect of temperature and aging on the mechanical properties of concrete: Part I.

Meanwhile, changes in the leaching characteristics and physical properties were analyzed.
Although elevated temperature and freeze-thaw cycles led to the deterioration of geopolymer matrices, the leaching rate and mechanical properties of solidified product were still acceptable.
Geopolymers have been used to encapsulate intermediate level nuclear waste (ILW) such as radioactive Cs and Sr because of the excellent properties such as fire resistance, micro-bacterial resistance and high compressive strength[1,3,4].
Hence, it is of great necessity to illustrate the thermal properties of this geopolymer.
According to the literature, Thermal incompatibility, pore pressure effects and phase transition are critical factors that affect the strength evolution of Portland cement-based compositions at an elevated temperature[7].

China Mechanical Engineering, 2000, 11(2):144-149
Effect of structure parameters on dynamic properties of spindle system[J].
Mechanical research & Application, 2006,19(5):12-14
China Mechanical Engineering, 2000,(11)6:601-607
China Mechanical Engineering, 1998,9(12):48-52

Mechanical Property Test.
Samples of mechanical property test are processed according to China national standards GB/T288-2002 and GB/T299-1994.
Test Result Microstructure and Mechanical Property.
Table 1 Mechanical property of test materials Test materials Tensile strength [MPa] Yield strength [MPa] Elongation [%] Reduction of area [%] Hardness [HRC] Impact toughness [J/cm2] 25Si2MnNi3 1535 1310 11.5 60.0 46.2 51 53Si2MnNi3 2250 1890 7.3 37.0 57.6 13 Mechanical property of test materials is shown in Table 1.
Under impact abrasive wear resistance condition, the hardness and the toughness are two main factors which affect the material wear resistance.

properties of ZnO films are known to be affected by the residual stresses in the films [1-3].
Mechanical properties of ZnO thin films such as adhesion, stability towards delamination etc.
There are many factors proposed to be playing a role in the creation of these stresses, e.g.
Discussion It is known that the residual stresses in thin films affect the functional (optical, electrical, magnetic) properties of those films.
Hence, it is crucial that the stress buildup is controlled during film growth to achieve strong films with sustainable properties for device applications.

In the model, many factors were considered such as liquid metal turbulence, latent heat of phase transformation and material thermo physical properties depending on temperature.
Material properties.
As a result of AZ31B magnesium alloy material under high temperature thermal physical property parameters are difficult to be measured accurately, the existing literature on the physical properties of the material research mainly concentrated in low temperature(room temperature 800˚C),so this paper combining with the existing data with numerical extrapolation method to study[5](Fig.2).
(a) Specific heat capacity (b) Thermal conductivity (c) Density Fig.2 Thermo-physical properties of AZ31B depending on temperature Boundary conditions.
(2) Through the preparation of procedures for considering the pool of latent heat of phase change, the molten pool liquid metal molten pool convection: solid-liquid interface of mobile and thermal properties with temperature changes and other issues, allowing the simulation of actual conditions

Considering this, the authors investigated the newly proposed FS3D tube to find the heat transfer factors.
Information about some of the properties is presented in Table 2.
It is declared that viscosity is the most important property which may be changed by temperature.
Figure 5 shows the relation between Reynolds number and friction factor.
The physical properties of the fluid and its operational condition affect the heat transfer coefficient.

The air flow velocity at the rotor disc is[5] (1) Where is referred to as the axial induced factor.
In case of a wind turbine undergoing a periodic surge motion, in this paper expressed as (2) Thus, the effective air inflow velocity at the rotor disc: (3) 1.2 S.Øye dynamic inflow model In BEM theory, flow properties such as velocity and pressure at the rotor disc are determined by steady axial momentum equilibrium between air flow infinitely far upstream and downstream of the rotor disc.
More than 15 cycles of surge motion are completed before the end of simulation to ensure that all the start-up transient factors are eliminated.
However, when comes to the wind speed of 16m/s, each parameter is minimally affected by the surge motion.
“Mechanical characteristics of some deepwater floater designs for offshore wind turbines.”

Mechanical properties and constitutive model study of Cemented Sand and Gravel is key to Cemented Sand and Gravel faced eath-rockfill dam.
Basing the Mechanical properties triaxial experiment of the material, the paper gives further discussion on the constitutive model of Cemented Sand and Gravel.
Hyperbolic model has the following several characteristics: (1) Suppose the relation between axial strain and deviatoric stress as hyperbolic curve, the tangential modulus can be determined from the results of ordinary triaxial soil tests; (2) Assume materials are homogeneous; (3) adopt Mohr-Coulomb strength theory; (4) Consider effect of stress level factor and nonlinear feature that the material tangential modulus changes with deviatoric stress changes
(5) 、、、、、、、 are 8 parameters affect initial modulus and Poisson’s ratio contained in the model (2) Establishment of Cemented Sand and Gravel Constitutive model There was a descending part after peak value on the strain and stress relation curve, namely the stage of strain softening phase that deviatoric stress decreases with the strain increase , the tangential modulus must be negative, hyperbolic model mentioned above can be used directly, hence, the paper uses the virtual rigid spring method to handle the strain softening problem. 1) Basic theory of virtual rigid spring method (a) stress-strain diagram (b) assumed-spring method Fig.1 Schematic diagram of assumed-spring method The relation curve between strain and stress of spring is linear illustrated by the straight line OA in the Fig.1 (a).