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The molding and the mechanical properties of rubber product will be affected if Mooney viscosity is low.
Money viscosity of natural rubber is related to many factors such as strains of natural rubber tree and production technology of natural rubber1.
However, the physical and chemical properties of natural rubber and the aging resistance of natural rubber will change with addition of hydrazine dihydrochloride or hydrazine sulfate.
During storage of natural rubber at room temperature, owing to the effect of the environmental factor(mainly light, heat and oxygen), the natural rubber molecules degrade, causing the natural rubber to depolymerize and turn to a nonelastic state, then lose its performance characteristics at last3.Zhang et al.4 studied the effective storage time of natural rubber at difference storage condition, however, no paper is available about the study on the effective storage time of natural rubber containing hydrazine dihydrochloride or hydrazine sulfate.
Table 1 The largest peak temperature Tp of oxidative exothermal peak activation energies of oxidation reaction of rubbers tackifier heating rate (℃/min) activation energy (kJ/mol) correlation coefficient 4 5 6 8 10 the largest peak temperature of oxidation exothermal peak Tp (℃) the control 189.11 193.43 200.22 203.50 104.7 0.9877 hydrazine dihydrochloride 190.04 194.41 195.80 200.77 205.65 105.6 0.9935 hydrazine sulfate 189.52 193.91 194.91 201.79 204.60 103.1 0.9906 Effect of tackifier on effective storage time of natural rubber Heat aging life equation of high molecular weight materials The heat aging life equation6,7 of high molecular weight materials is usually as follows τ= + (3) Where a is a constant, the intercept of aging life line; b is E/2.303R, E is the activation energy of oxidation, and R is gas constant (R= 8.314); T is ambient temperature K; τis the time need when the properties of high molecular

Studies on Al-Mg, Al-Cu, and Al-ZnMg-Cu alloys showed that the size and dispersion of the second-phase(s) can affect the cavitation erosion behavior [2].
Additionally, some authors affirm that there is a correlation between cavitation erosion resistance and mechanical properties of an alloy [6, 8], while others mention that there are no clear relationship [4].
As known, in semisolid processing the microstructure of the alloy changes from dendritic to globular [10], improving mechanical and corrosion resistance [11-13].
It follows that the microstructure can influence the cavitation erosion resistance but in combination with other factors, like for instance chemical composition or mechanical properties.
Hu, Processing, microstructure and mechanical properties of magnesium matrix nanocomposites fabricated by semisolid stirring assisted ultrasonic vibration, J.

The heat transfer by radiation can be easily controlled by controlling intensity of radiation or alteration of surface properties.
Sheet material properties are temperature dependent.
The effect of the changes is affected by material parameters such as its physical properties and by its shape
· It is possible to control the deformation parameters and the thermal phenomena by the changes of the material shape and by the changes of the material properties
Meddad: Sensitivity of operating conditions and material properties for thermoforming process, Plastics, rubber and composites, 29, 4 (2000), 163-167

The conformability can be expressed concerning material properties by equation (1).
The contemporary materials employed in oil control rings and some of their properties are plotted in Figure 3.
The pointed gray area in figure 3 indicates graphically those aimed properties and the arrow shows how the oil ring material may evolve in the near future.
Density is of paramount importance with respect to the properties of sintered parts.
The gray area represents the range of aimed properties.

Introduction Nickel-base superalloys are used in both land and air-based gas turbine engines, due to their superior high temperature mechanical properties.
The distribution of precipitates will evolve with processing or with thermal exposure in the gas turbine engine, resulting in corresponding changes to the alloy mechanical properties.
It is therefore desirable to non-destructively monitor this evolution in the precipitate phase, so that the mechanical properties of gas turbine engine components might also be monitored in the future.
The geometric correction factors used to convert the resistance values to resistivity are described elsewhere [8].
Volume distributions of the g’ phase were fit to the measured SANS intensity by assuming spherical particles and a hard sphere model for the structure factor.

Solar Cell Surface Texturing Combined Wet Etching and Ultrasonic Vibration Yan Chaoa, Yutao Wub, Jie Yuc and Liqun Wud School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang Province 310018, P.R.
Front surface texturing in crystalline silicon solar cells has a primary role for improving cell efficiency by means of its antireflection property and light trapping with antireflection [1-3].
Wet chemical processes etch and dry processes etch are two main methods in silicon surface texture preparation, wet chemical etch used sodium or acid to produce pyramids texture on oriented material, while the dry method such as laser-structuring [6], mechanical diamond saw cutting [7], photo-lithographically defined etching [8], porous-Si etching [9], mask less RIE etching [10-11] is recently present to prepare the theoretic texture.
Sodium or acid etching is a stochastic process, and the pyramids structure can be not made regularly, which will affect light trapping.
Since the vibration of molecular is influenced by acid damp, friction between acid molecular and other factors, the motion is a two-stage vibration system.

Introduction Recently, many researchers have been conducted many researches deal with the sustainable materials or how to reduce the wastes in the world, such as using the polyethylene terephthalate PET wastes in concrete to enhance the mechanical properties of the concrete as well as produce an eco-friendly concrete [1,2].
Its chemical and physical properties and its compositions are given in Tables 1.
Table 1: Chemical and physical properties of tested cement Oxide Composition Abbreviation By weight% Limitations of specification Lime CaO 60.6 - Silica SiO2 22.4 - Alumina Al2O3 3.02 - Iron oxide Fe2O3 5.24 - Sulphate SO3 2.34 ≤ 5% Magnesia MgO 2.3 ≤ 2.8% for C3A ≥5% Loss on Ignition L.O.I. 2.27 ≤ 4% Lime saturation Factor L.S.F. 0.98 0.66-1.02 Insoluble residue I.R. 0.78 ≤ 1.5% Main compounds (Bogues eq.)
Loza Yañez, “Effects on mechanical properties of recycled PET in cement-based composites,” International Journal of Polymer Science, vol. 2013, no. 1, pp. 1–7, 2013
Roman, “Mechanical properties of recycled PET fibers in concrete,” Materials Research, vol. 15, no. 4, pp. 679–686, 2012

Important features which characterizes them are their amorphous structure and unique mechanical properties.
This effectively can be used for the evolution of preferred phases and thereby can be used to affect the properties of the alloy.
Thadhani, Mechanical properties of bulk metallic glasses.
Shiflet, Mechanical properties of iron-based bulk metallic glasses.
Vander Sande, The effects of devitrification on the mechanical properties of Cu46Zr54 metallic glass.

Simulation on the Dielectrophoretic Assembly of Carbon Nanotubes Shaohua Zhen1,a, Libao An1,b,*, Chunrui Chang2,c 1College of Mechanical Engineering, Hebei Provincial Key Laboratory of Inorganic Nonmetallic Materials, Hebei United University, Tangshan, Hebei 063009, China 2College of Science, Hebei United University, Tangshan, Hebei 063009, China azhen_shaohua@163.com, blan@heuu.edu.cn, cchangchunrui@heuu.edu.cn *Corresponding author keywords: Carbon nanotubes, Dielectrophoresis, Assembly, Simulation.
Introduction Since their discovery in 1991, carbon nanotubes (CNTs) have attracted great research interests due to their unique one-dimensional structure and outstanding properties [1].
The DEP force due to the nonuniform electric field can be expressed by [15] , (1) , (2) where r is the radius of the particle; l is the longest dimension of the particle; εp is the permittivity of the particle; εm is the permittivity of the medium; KA is the Clausius-Mossotti factor which is related to the complex permittivity of both the particle and the medium.
The alignment of CNTs will be affected due to the existence of floating electrodes.
In the quadruple electrode structure, because the floating electrodes alter the electric field distribution, the alignment of CNTs will be affected.

In fact, in addition to viscosity, the surface tension and affinity of the slurry to the poured medium are also the main factors affecting the permeability [7].
The main physical and mechanical properties of CW epoxy grouting material are shown in Table 1.
The main physical and mechanical properties of CW epoxy grouting material Items 6:1 5:1 Initial setting time (h) 65 46 Slurry density（g/cm3） 1.06 1.07 Compressive strength (MPa) 62 68 Shear strength (MPa) 12 15 Tensile strength (MPa) 16 20 Bond strength (MPa) Dry 4.8 5.2 Wet 4.2 4.0 The method of sample preparation: After the samples were placed under standard test conditions for 24 hours, component B was slowly poured into component A according to the recommended mixing ratio and fully stirred and mixed evenly. 2.2 Test equipment and methods (1) The viscosity of CW epoxy resin slurry was measured by NDJ-79 rotary viscometer of Shanghai Changji Geological Instrument Co, Ltd, at different time and the test temperature was 23℃.