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However, there are few reports on the tribological properties of QBe2 so far, so it has great significance to study its tribological properties, wear resistant mechanism and the influencing factors.
The wear resistant property usually requires not only itself with good wear resistant but also its couple, and the two together constitute the mechanical system of the wear resistant property.
In addition, the actual using environments such as different surface roughness, loads and corrosion period under acidity will affect the tribological properties of the material.
The tribological properties are showed in Figs. 6 and 7.
The prior corrosion process reduces the tribological properties on the whole.

Particular attention is paid to recently reported correlations between melt fragility and the vibrational and mechanical properties of the ensuing glass.
Instead the imprint of non-ergodicity is felt at the glass transition in the melt fragility and at lower temperatures in the non-intuitive empirical relationships recently discovered between this single rheological parameter and the non-ergodic and mechanical properties of glasses.
Non-ergodicity factor.
(a) Log I(Q) versus Q 2 at the base of the structure factor for glass and liquid [10].
Phillips: Amorphous Solids: Low Temperature Properties (Springer-Verlag, Berlin 1981)

Traditional ejection seat separation control system is a kind of mechanical height-time single control organ, because the time interval spanning from the seat ejection to the shoot and lifesaving parachute is fixed.
The polymorphic program controller was developed in the sixties abroad, and in the seventies, electronic programmable device with higher development property was began and researched significantly in the US and UK and other countries with the rapid development of electronic technology, recently, electronic adaptive program controller with more advanced technology.
The Advantages of Electronic Program Controller Compared with the mechanical program controller, the electronic program controller has the following advantages: (1)small size, light weight, high precision of time delay
And the defect is that it is easily affected by external factors.
Multiple factor input, multifunctional output and adaptive control technology requirements, makes the program controller move from the fixed delay to variable time delay, develop from single time delay functional to multi-functional and intelligent direction, change from mechanical to electronic direction, and the electronic way is an inevitable trend in the development of programmable device.

Table 1 summarizes their mechanical properties.
Prior to fatigue testing, all of the specimens were electro-polished about 25µm from the surface layer to remove the work affected layer and make the surface observation easier.
As seen from the figure, both of initiation and propagation of a crack are Fig.1 Microstructures Table 1 Mechanical properties Fig.2 Shape and dimensions of specimen (c) L1 (b) M (a) S 10 5 106 107 0 100 200 300 400 500 600 700 800 RH% 25 85 △　▲　S ○　● M □　■　L1 Stress amplitude,σa (MPa) Number of cycles to failure, Nf (cycle) Fig.3 S-Nf curves 0 1x10 5 2x10 5 3x10 5 4x10 5 0.01 0.1 1 10 RH 25% RH 85% L1 σa=550MPa Coalescence of cracks No crack Crack length, l (mm) Number of cycles, N (cycle) Fig.4 Crack growth curves 0 1x10 5 2x10 5 3x10 5 4x10 5 0.01 0.1 1 10 RH 25% RH 85% L1 σa=550MPa Coalescence of cracks No crack Crack length, l (mm) Number of cycles, N (cycle) 10 5 106 107 0 100 200 300 400 500 600 700 800 RH% 25 85 △　▲　S ○　● M □　■　L1 Stress amplitude,σa (MPa) Number of cycles to failure, Nf (cycle) accelerated by humidity and the influence of humidity
As the factors of the accelerations in both processes of initiation and propagation of a crack, lowering of surface energy due to water absorption and hydrogen embrittlement are considered.

The physical and chemical properties of cement and bottom ash is given in Table 1.
The fresh properties of the concrete are as presented in Table 3.
The decreased in workability is due to two factors firstly, the micro pore in bottom ash absorbp both water and cement paste during the mixng, and secondly, the irregular shaped particles of bottom ash increased the inter-particle friction between aggregates hence decreasing its workability [13,14].
Table 3: The fresh properties of self-compacting concrete Sample BA0 BA10 BA15 BA20 BA25 BA30 Slump flow dia.
The results suggested that the bonding between aggregate and cement paste are the most important factor in affecting the strength of concrete especially the tensile strength.

The reason is that the electric powder, such as silicon, titanium, suspended in working fluid affects the discharge process.
Behavior of powders was observed in detail to analyze how the debris in the gap affect discharge occurrence[5, 6].
The powder in the discharge gap may be regarded as the most important factor for process stability as it has a significant influence on the factors like discharge transitivity, gap size, breakdown strength and deionization of dielectric fluid.
It is required to investigate and correlate the influence of these factors for the control of PMEDM process [8].
Under the action of mechanical agitation, additive powders will suspend and distributed in liquid.

It is presented in literature as a biomaterial that presents the potential to regenerates soft and hard tissues because of their appropriate mechanical, physical and biological properties like strength, elasticity and an excellent metabolic biodegradation rate with no toxicity of liberated metabolites [1].
Experiments show that chitosan does not affect the structural arrangement of collagen.
It is known that properties like: water absorption, viscosity, traction resistance, deformation and individual biopolymer morphology are found in blends in a controllable way, depending on their proportions in mixture [1].
We could observe that the porosity was a major factor to observe significant calcium phosphate deposition on a chitosan-collagen blend membrane, revealing a more intense in vitro calcification on porous membranes. 5 References [1] Tonhi, E.
Some biological and mechanical properties, Biomaterials, vol. 17(4), p. 451-455, 1996

ANOVA was performed to find out the significance of each factor.
With the emergence of Micro Electro Mechanical Systems (MEMS), Micro Wire Electric Discharge Machining (µ-WEDM) has made a significant inroad in the fields of medical, optical, aerospace, mould, tool and die making industries. µ-WEDM process involves the complex erosion effect by rapid, repetitive and discrete spark discharges between the wire tool electrode and workpiece immersed in a liquid dielectric medium.
From the analysis of variance and normal probability plot, it is observed that the significant factor affecting surface roughness in aluminium is the capacitance.
From the ANOVA, the capacitance is observed as the most significant factor.
In this work, a unique approach for modeling and optimization of µ-WEDM process is developed using theoretical modeling by considering thermophysical properties.

Nuraini1,c, Mohamad Ridzwan Ishak2, d 1Deparment of Mechanical and Manufacturing Engineering Department Universiti Putra Malysia 43400 UPM, Serdang Selangor, Malaysia 2 Departments of Aerospace Engineering, University Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aalkbir74@yahoo.com ,bsapuan@upm.edu.my, cnuraini@upm.edu.my, dmohdridzwan@upm.edu.my Keywords: Hexagonal tube.
The failure modes depend on variety of factors associated with the properties of the fibers and matrix and conjointly the preparation of the fibers, furthermore on the geometry of the shell of composite tubes [7].
Several studies have been conducted to investigate the crashworthiness characteristic of natural fiber reinforcement polymer composite material as an energy absorption capability due to the good mechanical properties low cost , widely commercially availability and andbiodegradability.of this material[8,9,10,11].
The quasi-static axial crushing behavior of hexagonal composite tube in affected by their structure length. 2.

This is one of the most determining factors of the tool or equipment’s longevity.
The physical behaviour of the material i.e. anisotropic material and isotropic material is a factor affecting the engineering structure.
Materials which have same physical, mechanical, and electrical properties in all the directions are called Isotropic material and on the other hand if they have different properties in different directions then these types of materials are called anisotropic material.
It is concluded that there is very little impact of the above factors on stress.
The authors concluded that cylinder properties approach the properties of a metal base (it has a smaller modulus of elasticity) and radial strain changes from positive values to negative values and tangential strain increases in the positive direction as the value of n increases.