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A large number of positron annihilation studies on metallic glasses has been carried out which are extensively reviewed in references [7-10].
This may be associated with the presence of appreciable number of quench in nuclei in groups, excess trapped vacancies etc. in the form of cluster of structural free volumes of amorphous state which is known to be a function of processing conditions [13].
In these situations small increase in nano-size crystalline particle volume fraction results in larger grain boundary/interfacial area, and hence increases in I2 or correspondingly decreases in I1.
Larger life component in heat treated samples above 450 oC could be ascribed to positron annihilation in crystalline-amorphous and crystalline-crystalline interfaces/ grain boundaries.

The particle is W7 AI2O3 with primary mean grain size of 6.3�m.
Three types weight percentage grain to fluid are used as the solvents, which are 5�,10� and 15�.
Numerical formula is defined in Eq. (2) ∑ −− = + − = 1 0 ,2,1 1 )( rN n rnn xy YY rN rhR �r=0,1,2,3…,m�mnumber, m is maximal transverse displacement number, N is sampling capability, h is sampling spacing, n,1Y and rn,2Y + are profile height in n and n+r location, respectively.

Simple coarse-grained models of the components used in this study are shown in Fig. 1.
Fig.1.Coarse-grained models of Carmustine, water and konjac glucomannan (KGM).
Acknowledgement The authors are grateful to the doctoral fund of Southwest University of Science and Technology (contract number:10zx7104) and Opening Fund from Engineering Research Center of Biomass Materials of Ministry of Education, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China(contract number:09zxbk01) References [1]Kuo,Y.

When an appropriate quantity of compound, which consists of small grains with almost 10µm diameter and emulsion, is pasted on the workpiece, buffing is conducted.
Sandpaper polishing for 7 sec Buffing for 70 sec Evaluation of polishing Buffing for 250 sec In case of 5000,10000,15000,20000min-1 Evaluation of polishing Fig. 1 Flowchart of polishing tests 2.5mm Rotational axis of tool Rotational axis of XY stage Polishing Surface φ37 φ32 Buffing tool Buffing tool Workpiece (acrylic urethane resin) Force sensor Compound Fig. 2 Schematic diagram and appearance of buffing tests Table 1 Polishing condition with sandpaper Diameter of sandpaper [mm] φ32 Mesh number #3000 Polishing pressure [Pa] 3000 Rotation [min -1] 5000 Polishing time [s] 7 Table 2 Polishing condition of buffing tests Size of tool (diameter×height) [mm] Φ32×6 Material of buffing tool Wool Size of abrasive grain in compound [µm] Less than 10 Polishing pressure [Pa] 800 Rotation [min -1] 3000, 5000, 7000, 10000, 12000, 15000, 18000, 20000, 22000 Polishing time [s] 70, 250 0 50 100 150 200 0 5 10 15 20 25 30 35 40
The total number of data used for this figure is 40 per workpiece.

The results of a number of investigations indicate that the mechanisms of the sigma phase precipitation strongly depend on chemical composition and annealing parameters [1, 5].
The value of the PREN (Pitting Resistance Equivalent Number) factor was estimated within the range of 35÷38.
Increasing the temperature of annealing up to 950°C caused growth of ferrite grain and the sigma phase.
The changes of the intensity of the principal components of textures of annealing of ferrite and austenite were connected with the decomposition of ferrite, the precipitation of the sigma phase and secondary austenite and also with the growth of grains.

What’s more, a large number of the organic compounds’ volatilization under high temperature will go against the smoothness and the compactness of films.
It can be seen on the surfaces of LSGM films from Fig.3 b-d, with increasing numbers of coating cycles, the amount of holes reduces significantly and compactness of films increases.
It is noteworthy that films of 7 and 9 coating cycles appear abnormal large grains.
The reason may be that the thicker films go against heat dissipation, which lead to the abnormal growth of grains during the sintering process.

The characteristic equation (Eq. 1) proposed by Hakki and Coleman [6] relating resonant frequency, dielectric constant (or electric permittivity) and resonator dimensions (radius a and height H) for electromagnetic TE011 mode is: (1) where: ; and k1 = wave number inside the DR; k2 = wave number outside the DR; J0(k1a) = Bessel function of order 0; J1(k1a) = Bessel function of order 1; K0(k2a) = modified Bessel function of order 0; K1(k2a) = modified Bessel function of order 1; b = p/H = propagation constant; c = speed of light; a = DR radius = D/2; H = resonator height; er = dielectric constant of DR; ea = dielectric constant of air (ea = 1); fr = resonant frequency.
From microstructure images it can be observed that Ga2O3 influences the grain growth of sintered ceramics.
Other factors such as grain size, polarization and conductivity of microstructures can also affect the properties, although with less intensity; we can consider that microwave dielectric properties are affected more by the crystalline structure and chemical compounds present in each one of the investigated ceramics.

Based on the features of the methods of obtaining spherical powders in order to obtain spherical granules of a regulated grain size, the technology of electroerosive dispersion is proposed, characterized by relatively low energy costs and ecological cleanliness of the process [18-25].
Grinding produced metallographic paper with a large (№№ 60-70) and fine grain (№ № 220-240).
The use of stereoscopic metallography techniques allows us to calculate the specific surface area of large pores, the number of spherical pores per unit volume, the average distance between the pores, the average real diameter of spherical pores, etc.the Metallographic method covers a wide range of pore size measurements corresponding to the resolution of the optical ability (for an optical inverted microscope Olympus GX51-500 nm).
Project number is 17-79-20336.

Laboratory techniques and modelling procedures utilized in contemporary materials engineering deliver a wide range of computer-aided methodology enabling one to obtain valuable parameters and information on material, including crystallographic texture,) Crystallographic texture is a statistical property of a material with crystalline structure manifested by the ordering of the spatial orientation of the particular crystallites (grains, sub-areas, and particles).
Similarly to the dislocation structure, the distribution and the number of structural defects (shear bands), residual stresses, or the volume fraction of the material undergo changes in TSL during exploitation leading to deterioration, and the spatial distribution of the orientation of crystallites and grains, i.e. the crystallographic texture of this layer, undergoes modification.
The developed methods of texture analysis provide the possibility of non-destructive monitoring of subtle changes in the preferred orientation of grains, which is very important in the case of thin near-surface layers [2, 3].
Tribological tests of each pair were stopped at the beginning of the damage phase of the wear process, which was ensured after an established number of testing steps.

According to Birch et al. [12], the compressional velocity in oxides and silicates is a function of two principal variables (i) density and (ii) mean atomic weight (m) (molecular weight divided by the number of particles in the molecular formula (M/7)).
This suggests that the magnitude of elastic constants is heavily affected not only by percentage of porosity but also by shape, size, their distribution and connectivity of pores, anisotropic thermal stress induced occurrence and development of micro-cracks, crack density (number of cracks per unit volume),crack shape (circular, ellipsoidal, long rectangular etc.), grain and grain boundary contribution to the polycrystalline materials [13,15].
On the other hand, the valleys which occur between grains, provide sites of large stress concentrations and consequently, large deformations.