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The study of polyurethanes are of continuing interest due to their excellent physical properties.
Introduction Polyurethane is an important class of polymer with many advantageous properties, its chain structure is composed of alternating sequences of hard and soft segment.
Various physical properties are designed by adjusting composition and proportion of hard and soft segment to meet the demands of modern technologies [3-4].
Fig. 5 FT-IR spectrum of Polyurethane Fig. 6 GPC chromatogram for Polyurethane Hydrogen bond in system directly affects the properties of materials.
The content of hydrogen bonding in the N-H group could be obtained by using formula (4), the result was 80.75%, which manifested that the large amount of N-H were present in hydrogen bonding which influenced the properties of the polyurethane.

Landslide disaster has caused huge losses to human life and property, which has brought the serious influence to the engineering construction[1~2] as well. 
The landslide slope stability is its natural adjustment, what influence the steady state effect factors are natural and human activities.
Frame type model test adopt the similarity model materials and the criteria in the framework by making model in normal gravity, and measure its deformation, stress and other factors in the model satisfying the boundary conditions of similar cases, and then reveal the formation mechanism of the landslide prototype[4]. 
We can control the elevation angle in a certain range, but the large section hydraulic cylinder will appear crawl phenomenon when it is in the low great pressure, thus causing pulsating torque when the hydraulic pressure lifting the landslide model box, and the pulsating torque will affect the landslide model experiment. 
Changeable factors associated with water, soil water and soil factors such as landslide movement.

Preliminary roasting and leaching purification technology route was proposed according to the above analysis results, and analysis of the purification process related factors was made.
Mechanical rod mill for 30 min, added a small amount of dodecyl benzene sulfonic acid sodium, let stand, filtered in the acid pickling, then washed to neutral with water, filtered sample was dried at 105℃.
Fig.1 Manganese anode slime removal of lead process route The route design was based on three points: 1st, mechanical polishing could destroy the crystal structure, cause local defects, and make crystal particles in thermodynamic instability state, the particles were activated, the system activation energy was decreased, in the actual processing, anode slime of over 200 mesh continued to grind to more fine; 2nd, high temperature roasting, by changing the crystal space structure to make the embedded impurities expose, destroyed the chemical bond between cation and chemical bonds [MnO6] at the same time; 3rd, the choice of the leaching solution, selecting the appropriate leaching agent could selectively leach out the impurity ion distributed in the manganese compound in the form of a coordination compound, while manganese compounds were insoluble in order to achieve solid- liquid separation.
Results and analysis Physical and chemical properties.
Roasting environment [19], mainly oxygen partial pressure can affect the roasting temperature selected, oxygen partial pressure reduce, which can make MnO2 every oxygen loss at lower temperature, while, roast atmosphere directly affect heat absorption peak in the TG/DTA, as well as the kinds of roasting production, and whether the product is a pure substance.

"Experimental investigations of mechanical properties and slurry erosion behaviour of high velocity oxy fuel and plasma sprayed Cr2O3–50% Al2O3 coatings on CA6NM turbine steel under hydro accelerated conditions."
"Mechanical and microstructural properties of carbon nanotubes reinforced chromium oxide coated boiler steel."
"Experimental investigation on erosion performance and wear factors of custom 450 steel as the first row blade material of an axial compressor."
"Properties of HVOF-sprayed Stellite-6 coatings."
"Microstructure and properties of Al2O3-ZrO2 composite coatings prepared by air plasma spraying."

Good permeability, reliable physical and mechanical performances are requirements of overall performance of permeable concrete which need to be improved in the aspect of aggregate structure.
Therefore, by adjusting the size and content of semi-large particles can change packing structure, thus affects pore size.
For octahedron packing structure made of particles with single pore size, the most probable void size is about 0.4 d and the ratio between particles with the size of 0.4 d and general voidage is the key factor that determines the strength and permeability of packing structure.
Jiang, Experimental study on properties of pervious concrete pavement materials, Cement and Concrete Research, Vol. 33,(3), pp. 381-386, 2003
Okamoto, et al., “Properties of high-strength porous concrete”, Recent Advances in Concrete Technology, Fifth CANMET/ACI International Conference on Recent Advances in Concrete Technology, Singapore, pp.173-187, July-August 2001

Since the longevity of total hip joint prostheses is affected by the wear of their components, one of the main objectives of orthopaedic research is to validate different bearing surfaces with a reduced mechanical wear.
The mechanical properties of different UHMWPE acetabula cups are summarized in Table 1.
Table 1 Chemical and mechanical properties of UHMWPE acetabula with various molecular weights made by different moulding process Molecular weight Consolidation methods Specific density (g/cm3) Hardness (HB) Tensile strength (MPa) Melting point (°C) Water absorption (%) 3,000,000 Thermal extruding 0.935 30 35 136 <0.01 4,500,000 compression moulding 0.935 31 34.6 138 <0.01 6,000,000 compression moulding 0.941 69 29.3 143 <0.01 The precision finishing of consolidated UHMWPE samples is required to obtain the smooth surface and limited clearance between the artificial acetabula cups and femoral head balls.
Therefore, the wear factor is
Among these factors, the particle size and morphology are possibly the most powerful impacts on the biological reaction to biomaterial wear debris.

Although the role of some factors (like GB’s migration or GB’s composition) and the nature of the measured parameters in the different diffusion regimes may be more quantitatively understood now, some questions (like the role of stresses or the value of the diffusion coefficients in non-equilibrium GBs) still remain open problems.
In case of precipitation of a three dimensional phase, it is difficult to separate the respective roles of this new phase and that of the modifications directly induced by the equilibrium segregation on the diffusion as well as on other properties like the stabilisation of nano-structures.
The effect of stresses on GB diffusion as well as other physical properties of materials remains an open problem [40, 41].
The difference between the thermal expansion properties of the substrate and the layer (s) generates the stress state.
There are for example some evidences that mechanical attrition creates GBs with a higher energy than that present in equilibrated high-angle GBs [60].

Load Spectrum Compilation Based on Nonparametric Statistical Extrapolation Zhiqiang Xu1,a, Hongjian Wang2,b, Mingyao Yao2,c 1 Department of Physical Science and Technology, Kunming University, Kunming, 650214, China 2 College of Mechanical Science and Engineering, Jilin University, Changchun,130025, China azqxkmu@yahoo.com.cn, b414039405@qq.com, cyaomingyao@126.com Keywords: Load Spectrum, Rainflow, Nonparametric Extrapolation, Kernel Function Abstract: Considering the special load characteristics of the wheel loader, this paper focus on compiling the load spectrum of the transmission of the wheel loader using the nonparametric statistical extrapolation method (NSEM).
Hence, load spectrum is widely used in the mechanical field.
There are many human factors in this method, so the statistical results are not satisfactory.
The kernel function is the critical issue in the NSEM, which directly affect the result of extrapolation.
In order to obtain useful signal properties embedded in the tested signals, the signals should be further analyzed and processed.

Introduction Traditional micro-electro-mechanical systems (MEMS) technologies based on silicon manufacturing processes are not suitable for manufacturing three-dimensional (3D) structures in metals.
In the finite element simulation of micro cutting, the determination of the suitable constitutive model is very important because these parameters of nominal physical and mechanic property vary for different constitutive model, which reflect whether the simulation results are correct or not.
The nominal mechanic property of this cobalt alloy is shown in Table 1, which is used in the constitutive model of finite element simulation for micro cutting Elgiloy.
Table 1 Nominal mechanic property of cobalt alloy Young’s Modulus （Gpa） Poisson’s Ratio Shear Modulus （Gpa） Hardness （HV） tensile strength （Mpa） yield strength（Mpa） 189.6 0.226 77.2 700 2451~2530 1598~1667 Mesh and Calculation.
The processing parameter, the feed speed was selected as the main factor that may enormously affect the milling force, with four different values as 1 millimeter per second, 5 millimeter per second, 10 millimeter per second, 20 millimeter per second.

In the simulation of oil flow electrification process, the relationship between the above four parameters and the three types of influencing factors must be considered [9].
It still could not be determined that which effect was the real mechanical, or it was a combination of several effects.
That’s to say the characteristics of solid surface determined the electrical properties of the oil flow.
But this model thought that the polarity of charges in oil mainly depended on the activity of the positive and negative charged ions in oil, while the surface properties of solid materials only played a supporting adsorption role in the oil flow electrification.
Li, et al, Oil Electrification Phenomenon and Analysis of Factors to Influence Oil Electrification Phenomenon in Transformer, Transformer. 2008,vol.45(2),pp.29-32