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The full cycle of surface modification of the backbone with polyvinylpyrrolidone and drugs permitted to increase significantly the atrombogenic and antimicrobial properties of prostheses and provide its effective matrix properties.
The undoubted advantage of such modifications is that this approach allows one to directly adjust the surface properties of the material without changing its mechanical characteristics.
The simplest way to assess the properties of a surface is evaluation of its wettability with water under the advancing conditions.
(1) New tissue-engineered vascular prostheses of small diameter with effective matrix properties have been created.
However, ionizing radiation can affect biocompatibility properties.

This cutting heat can cause the deformation and wear of the work piece and the cutting tool, and affects machining quality finally.
The volatility of lubricating oil in the cutting area is relieved with brilliant cooling effect which at the same time improves lubrication, so that the whole effect factors cause in the cutting process tends to be a virtuous circle.
As the different physical properties, mechanical properties and relative processing of GH4169, TC4 and Cr12, their effects of reducing the cutting forces vary, but the overall trend is consistent.
China Mechanical Engineering 2000, (11) 7:738-740.In chinese
Mechanical 2000, (27) 3.

One of the main factors affecting the incidence of delamination close to the open edges is the stacking sequence.
However, it had a remarkable anisotropy for the mechanical properties and they showed premature failure due to effect of shear and local deformation (Fig. 5 and Fig. 7).
The specimens C and D show a nonlinear behavior with matrix cracking and a significant reduction in their mechanical properties in terms of flexural strength (Fig. 12 and Fig. 16).
However, it had a remarkable anisotropy for the mechanical properties and it showed premature failure due to shear and local effects.
Conversely, unidirectional [45]3S and [30]3S laminates showed a nonlinear behavior with matrix cracking and a significant reduction in their mechanical properties in terms of flexural strength.

The functionality of polyol has a profound effect on the properties of RPUF [10].
RPUF with good mechanical properties, very low density and excellent dimensional stability could be prepared by fully water-blown technology with various water levels.
With increased water level, the cream time, gel time and tack-free time of foaming mixtures increased accordingly, while the density and mechanical properties decreased gradually and the cell diameter initially decreased and then increased [13].
The choice of blowing agent has a significant influence on a number of these factors.
This material forms a grid of cell struts and cell walls that can withstand mechanical loads due to its rigidity and cross-linking properties.

But in practical engineering,rock mass is in three- dimension stress state.So it is essential to establish the three- dimension constitutive model of unloading rock mass throughout the study on the relationship between load variety and rock mass property.
The mortar is simulated material.Mortar mix ratio, mechanical parameters and model similarity constants are shown in Table.1~Table.2.
Table.1 Ratio and mechanical parameters for mortar model sample ratio Unit weight (kN/m3) elastic modulus (Gpa) compressive strength (MPa) tensile strength (MPa) cohesive force (MPa) internal frictional angle (°) cement water Sand HC 1.33 1 5.96 2.03 6.67 14.3 1 0.21 54 Table.2 Similarity ratio for mortar model physical quantity length (m) elastic modulus (GPa) stress (MPa) strain cohesive force (MPa) similarity ratio 9 9 9 2.9 9 Geometric Parameters of Test Model (1) A group of structural surface Structural plane is divided into three groups: NWW（included angel ）group ; NEE（included angel）group ; EW（included angel）group .Characteristics of the structural plane is shown in table 3
Table4.Correlative data of EW joint stage 1 2 3 4 5 6 7 8 9 10 11 Et 25.904 25.116 18.234 15.255 12.884 9.978 7.409 6.669 5.953 5.756 5.379 J2/MPa 6.363 2.216 0.473 0.485 0.996 1.481 2.078 2.884 3.796 4.710 5.341 T/MPa 4.931 3.426 2.289 1.531 0.889 0.497 0.165 -0.166 -0.491 -0.774 -0.957 P/MPa 6.928 5.423 4.286 3.528 2.886 2.494 2.162 1.831 1.507 1.223 1.040 D(area density) 4.500 4.500 4.500 4.500 4.500 4.500 4.500 4.500 4.500 4.500 4.500 θ -0.637 -0.321 0.322 0.409 0.179 0.323 0.423 0.504 0.566 0.608 0.631 Et/E0 1.000 0.970 0.704 0.589 0.497 0.385 0.286 0.257 0.230 0.222 0.208 Unloading Parameter Illustration Many factors affect unloading constitutive relation.According to test results and sensitivity analysis,some main factors were considered,such as the second invariant of deviatoric stress tensor, lode parameter, normal stress and shear stress of structure surface, initial deformation modulus etc，The symbols of parameters are as follows： the second invariant of deviatoric stress

Although the vane turbine affected speed loss of the ship, the power efficiency gained to be found always positive.
a : induction factor CPt : power coefficient of turbine CTt : thrust coefficient of turbine Table 1.
Vane turbine at slipstream will change kinetic energy slipstream will become mechanical energy.
Thereby simply, the thrust propeller and negative thrust turbine can be illustrated with simple algebraical equation (7), (7) And of course, the total Thrust of the system was smaller and affected the speed loss of the ship.
Chen, A.M Reed, K.H Kim : A Vane-wheel propulsor for a naval auxilliay, ( DTRC - 89/023 , 1989) [6]. - : Simplified prediction of propeller inflow/outflow properties ( A Hydrocom Technical Report, No 129, 2003) [7].

Due to the complicated nature of fatigue mechanisms and the large number of factors that influence fatigue life, there is so far no unified approach that can treat all fatigue problems [1].
Geometry of component and load conditions are the two dominant parameters which will affect the mechanism of failure and crack propagation.
Specimen Geometry and Material Properties The austenitic type 316L stainless steel was utilized and investigated in order to characterize fatigue life at room temperature.
The mechanical properties for Type 316L stainless steel is presented in Table 1 meanwhile Table 2 shows the chemical composition of the material.
(a) (b) Fig. 1: (a) Austenitic 316L Type Stainless Steel and (b) its dimensions Table 1: Mechanical Properties of Type 316L Stainless Steel Mechanical Properties Type 316L stainless steel Yield Point, MPa 332 Tensile strength, MPa 673 Modulus of Elasticity, GPa 165 Strength at break, MPa 586 Elongation at break, mm 35.5 Table 2: Chemical compositions of Type 316L stainless steel [8] Element (%) C Ni Cr Mn P S Si Mo N 316L 0.020 11.21 17.38 1.86 0.027 0.0054 0.51 2.36 0.038 Experimental Fatigue test was conducted at Strength of Material Lab at Tenaga Nasional Berhad Research (TNBR) in Bangi.

Linear elastic stress intensity factors for circumferential and axial part-through surface cracked cylindrical geometries are considered in literature, e.g. [1,2].
The result is compared with nonlinear finite element results, which enable assessment of the fracture mechanics parameters for various crack configurations, material properties and loading conditions.
Material properties Chemical composition of API J55 steel, used for fabricating the examined pipe, is given in Table 1, while Table 2 contain its tensile properties.
Tensile properties of API J55 steel [4] σ0.2 [MPa] σm [MPa] A [%] 380 562 33 Testing of the surface-cracked pipe Experimental testing is conducted on pressurized vessel with a machined axial external surface crack in the base material.
This method is regarded as more universal in comparison with the standard ones, having in mind that the specimen shape and dimensions do not affect the results significantly.

Appropriate lubricant coated on contact pair is a solution to improve the contact property.
So it can avoid electrochemical corrosion between them. 3) Reduces the contact between environment and the surface metal of contact pairs.[2] As lubricants are generally insulator, in order to not affecting the contact resistance of the pairs, lubricant must reach boundary lubrication state.
Mechanical part contains probe fixture, loading unit and support stage etc.
Tab.3-1 Resistance behavior of contacts lubricated with lub-E F=0.5N F=1.0N F=1.5N Nor D&H Cor Nor D&H Cor Nor D&H Cor 10 mW 5800 0 0 2400 0 0 2000 900 0 100 mW 6100 0 0 2700 2300 1600 2100 2300 1400 1000 mW 6600 6600 4300 2900 2500 2500 2300 2600 2100 The resistance value and its lasting sliding cycles can be used to evaluate lubricant properties and the influence of environmental factors.
[3] Hiroyuki Nakagawa and Koei Matsukawa, Friction and Wear Properties of Tin Plated Sliding Contacts under Oil Lubricated Condition.IEEE.2002

To date, considerable work has been done on the mechanical properties and behavior of steel fiber reinforced concrete (SFRC) beams.
Factors Affecting Shear Strength Studies documenting the factors influencing the shear strength of high-strength SFRC beams have been extensively reported in literatures.
The increase in shear strength attributed to the interaction between the steel fibers and the concrete matrix is complex, and many factors were investigated and found to have an effect on the beam shear strength.
However, the widely accepted important impact factors are the concrete compressive strength (ƒc), the tensile reinforcement ratio (ρ), the span-depth ratio (a/d), the fiber aspect ratio (lf/df) and the amount of fiber in concrete (Vf).
The factor is shown as follows: