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Therefore, the normal abrasion mechanism of diamond grain and the influence factors are studied all the time [2].
The workpiece material for grinding was the black granite whose mineral compositions and properties were listed in Table 2.
Shearing sample Dynamometer Arm length Shearing block Shearing force pa sV wV Amplifier Dynamometer Black granite XF Computer Table 2 Compositions and properties of the workpiece Percentage of main minerals [%] Workpiece Shore's hardness Texture Compression strength [Mpa] Quartz Feldspar Mica and others Black granite 76 Fine and Compact 137 5 45 50 Table 3 The parameters of grinding experiment Spindle speed n [rpm] 3250, 5200, 6500 The depth of cut ap [mm] 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 The same size diamond grits were chosen during the fabrication of the grinding wheel, so the protrusion height of diamond grits could be considered equally, which means tangential force of single diamond grit (ft) can be calculated as: c t t Cbl F f =
It can be seen that most of the grains were micro-broken (see Fig.7) during grinding process, only a few of them were wearing down, and none of them were pulled-out or broken-off. 0.02 0.04 0.06 0.08 0.10 0.2 0.4 0.6 0.8 1.0 1.2 vs=6500r/min vs=5200r/min vs=3250r/min ft(N) Cutting depth( mm) Fig.6 Experimental results of ap against grit cutting force ft Fig.7 The grit micro-broken morphology From grinding experiments and shearing experiments, it can be found that brazing time and vacuum degree affected shearing strength greatly.
Xu and et al: China Mechanical Engineering, Vol.15 (2004) No.12, pp.1085-1088

The building envelope which is made up of different properties of materials, with good effects on sound insulation, sound absorption and noise elimination, can be widely used in noise control engineering.
The main factors of noise attenuation are diffusion and air absorption, the distance between sound source and the residential area is close, air sound absorption is less, negligible.
Analysis of sound insulation performance of the duty room wall: Duty room wall uses sandwich plate, the resonance frequency of plate structures is usually in the audio major areas, will affect the sound insulation effect.
With the increase of the incoming wave frequency, resonance effect gradually disappears, the influence of insulation amount affected by the surface density increases, quality is heavier, sound insulation is higher, too.
Beijing: Mechanical Industry Press, 285,377(2002)

The energy and mechanical effects lead to special physical and chemical influences.
Therefore, it is difficult to make copper electrodeposition on Zn alloy die casting due to its chemical property, structure, surface morphology and so on.
Fig. 1 Interface model of Zn alloy die casting According to the interface model shown in Fig.1, four key factors determine the well bonding between copper deposits and matrix: (1) Antiscuffing paste in the pores must be eliminated clearly, otherwise some small grease would appear as shown in Fig.2; (2) Current intensity should be well controlled under the electrocleaning process with positive pole in the acidic system.
The first factors are pretreatment ones and the last factors are determined by supplementary means.
Conventional stirring methods slightly affect on the thickness of diffusion region [11].

According to many researches on aluminum alloys, the evaluation of flow and die filling properties of alloys as well as their resulting mechanical properties which are depended on various process parameters are being investigated up to now.
In this case solid particles make a cluster and separate from liquid phase and it can reduce the homogeneity of properties.
Wall thickness influences on metal velocity, filling behavior, phase segregation, mechanical properties and microstructure.
These segregations would lead to lower mechanical properties and especially to inhomogeneous specimen properties.
Therefore it seems that unique properties are not achievable in all over the specimen.

Process temperatures stay below the melting point of the consumable material and are an important factor determining the quality of the resulting deposit.
The prominent aim is to keep and improve material properties during the joining of different materials.
The choice of process parameters is strongly dependent on the materials that are supposed to be processed sincethe necessary energy input depends on thermal properties of the materials [13].
Mechanical properties of friction surfaced 5052 aluminum alloy.
An investigation on thermo­mechanical and mi­ crostructural issues in friction surfacing of al-cu aluminum alloys.

China 3Laboratory of Optics, Terahertz and Non-destructive Testing & Evaluation, School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, P.
Various defects with different diameters and depths were simulated in PE pipes and they would affect the thermal distributions from which the relation between thermal images and defect sizes and locations would be established.
The failure of PE pipe systems is often due to older generation materials whose properties offer limited resistance against severe environmental and operating conditions.
The other factor is human error, committed in the supply chain and site construction of installed pipe systems [1].
It has the following materials properties: Density ρ=952 kg/m3, Thermal conductivity k =0.53 W/m∙K, and Specific heat Cp=2300 J/kg∙K.

The bioceramic material, engineered for its antibacterial properties, is evaluated for its cytotoxic response.
Acrylic resins comprise a huge percentage of ocular prosthesis due to excellent physical and mechanical properties [1,8].
Engineered to exhibit antibacterial properties, this nano zinc bioceramic orbital implant aims to enhance tissue integration and minimize adverse biological responses.
Below 0.25 M nZnO, no significant effect on antibacterial properties was observed.
The Disc Diffusion method was used in measuring the anti-bacterial properties of bioceramic orbital implants.

The pump wear and tear has relation to the velocity, mass concentration, grain size and flowage of the materials it pump, and the materials of rotor and other factors.
Tab. 3 Recommend rotational speed and pressure for different abradability materials Abrasion resistance mild general serious Speed (r/min) 400 600 200~400 50~200 The highest pressure (Mpa) 2.4 1.6 0.8 In addition,in the view of fluid mechanics,the allowed rotational speed of single-screw pump is limited by its net positive suction head, which means it is affected by the viscosity of materials and axial velocity.This peak rotational speed is always less than the allowable maximum mechanical speed.
Only if the import pressure is positive, we can use allowable maximum mechanical speed (the positive pressure feeder in the system can guarantee the import pressure is positive).
Papermaking sludge rheological properties of experimental research, environmental engineering, 2008 (12).
The new thick paste rheological properties test-bed development and validation.

These two factors lead to rapid tool wear during machining of titanium alloys, which in turn increases the manufacturing cost.
Thus the various factors affecting the process have to be understood in order to determine the trends of the process variation.
A number of experiments were carried out according to the design of experiment (DOE) to investigate the influence of various machining factors on EDM process.
Properties such as lack-of-fit, R-squared, adjusted R-squared, predicted R-squared and adequate precision are examined.
The pulse duration is affecting the surface roughness negatively as expected.

However, to separate one REE from other REEs is challenging due to their similar physical and chemical properties[4].
Quantitative Structure Property Relationship (QSPR) is a mathematical model in chemometry that is used to link physical and chemical properties with the molecular structure of the compound.
Physical and chemical properties of a compound have a close relationship with chemical structure, so the determination of physical and chemical properties is very important for various purposes, such as separation, purification, structure determination and synthesis.
The molecular structure of each chemical compound contains a description of information about chemical properties, physical properties or biological activity of these compounds [10];[11].
The energy and properties of molecules are largely determined by the arrangement of the atoms in a molecule (Murry, 1992) in [11].