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Toney et al. [6] and Horvath et al. [7] suggested the formation of CuO led to the reduction of Cu peak intensity with the rising of oxide peaks and thus contributed to the refinement of Cu grain size.
This was attributed to the released of accumulated strain that caused grain coarsening [16].
Besides, the high dielectric constant also caused the entrapped air coupled with microwaves, which enable pores closing without much coarsening of grains [3].
Acknowledgements The author would like to thanks to Universiti Malaysia Perlis (UniMAP) for financial support under Seed Money Grant (Grant number: 9014-00009).

However, porous components based on Ti2AlC are promising candidates for a large number of functional applications such as heat exchangers, filters, lightweight structures, catalytic supports, etc [7].
The formation of elongated grains (~ 30 – 40 µm) during the sintering process is very important in order to provide mechanical stability to the porous structures, especially for the structures with high porosity.
Mechanical properties of the porous structures are not measured in this work, but several works reported about the importance of these elongated grains on the mechanical response of Ti2AlC compounds [1][16].
Regarding the matrix, elongated grains with the characteristic layered structure of Ti2AlC were randomly oriented.

The first reason for this is the high corrosion resistance of a number of amorphous alloys in aggressive environments.
The surface morphology have been surveyed with atomic force microscopy [5] to show the following: the outer surface of F1 alloys contact side is completely crystallized; the average grain size is 80 nm; the free side is amorphous with small crystallized areas; the grain size on the crystallized areas is 20 nm; both sides of F2 and F3 alloys are crystallized.
The grain size is between 25 and 80 nm.

Control of the microstructural characteristics such as grain size, shape textures, porosity, density and packing factor is vital for ensuring the reliability of TiN films in structural and functional applications [3].
This is because the number of electrons in N2 is less than that in Ar.
The deposited nanocrystalline TiN film exhibits a characteristic pyramidal grain shape with crystallite sizes that increases with increasing working pressure.
In particular, TiN film deposited at 7 Pa shows an amorphous like structure without any grains.

In connection with the peculiar microstructures, the NiTi shape memory alloy (NiTi SMA) offers excellent properties, such as large output, superior shape memory characteristics and higher yield stress for plastic deformation, which make it very attractive for a number of new applications [1].
It has been found in the foregone researches that there are inevitable defects in large-areaed NiTi SMA thin film deposited on PZT substrate, such as inhomogeneous component distribution, local crystal defect and grain-oriented column structure [5].
Figure 8 shows the cross section images of the prepared composite samples with different physical dimension L fixed M=1mm.Through observation and comparison of the images showing in figure 8, it is found that the shape of the crystal grains in NiTi SMA thin film appears an equilateral polygonal geometry in L=2 mm, and that with creasing physical dimension L, the shape of the crystal grains losses gradually equilateral polygonal geometry and becomes complete oriented columnar in the L=5 mm.

Figure 3 represents a TEM micrograph inside the columnar grain of YSZ coating shown in Fig.2.
Voids or gaps were observed at the boundary between each columnar grain.
A large number of nano-pores were also observed inside the grains and around substrate/coating interface.

Introduction There are also niobium and rare earth rare etc.elements in addition to containing a large number of hematite in Baotou Bayan Obo ore.
Three kind of hematite with different iron grade(No.1 ore with TFe of 42%, No.2 ore with TFe of 30%, No.3 ore with TFe of 17%) from Concentrating Mill of Baotou Iron and Steel Company, grain of -74μm accounts for more than 90% of ores, composition was showed in Table 1; activated carbon, analar , specific surface area of 1033m2/g, a fixed carbon content of 98%, from Shandong Zibo Huaguang Chemical Plant.
The three types of roasting ores were prepared under the above- mentioned best reduction conditions, then ground into powders of 74μm in grain size and made magnetic separation under the magnetic field strength of 80kA/m(the first magnetic separation), the iron grade of concentrate and the recovery were given in Figure 3.
The results showed that iron grade of roasting ores(about 50%) was low after the first magnetic separation, but the iron recovery was very high(reaching over 90%), indirectly reflecting the good effect of microwave reduction roasting, that most of the weak magnetic hematite changed into a strong magnetic magnetite.Then the concentrate after first magnetic separation were ground into powders of -33μm of grain size and made magnetic separation under the magnetic field strength of 32kA/m (the second magnetic separation), the iron grade of concentrate reached about 60%, which met the requirement of iron-making.The results of the second magnetic separation given in Table2.

The walls of the pores were analyzed with energy diffraction spectrum (EDS), and a large number of compounds containing K, F and Mg elements were detected in the wall of large pores (the diameter above 100um).
The grain diameter of welding bead much smaller than that of base metal is equivalent under three different velocities, as proved that the equal solidification rate was produced.
TiB2, distributing in the grain or along the grain boundary, did not vary in comparison with Fig.5.

Lanthanum (La) [12], adding lanthanum additive has the following advantages: refine grain effectively; enhance viscosity between corrosion layer and active substances; improve the corrosion resistance of Pb-Ca-Sn-Al alloy; increase conductivity of anode layer; reduce Pb (Ⅱ) generation, thereby, reducing the premature capacity loss and extending the life of lead-acid batteries.
Li et al. have reported the performance of Pb-Ca-Sn-Al alloy, mainly in the more refined and uniform grain, can inhibit the growth of the passivation layer and so on [18,19] .
Wenqing Zhang reported that Pb-Ca-Sn-Al-Re has high performance, reflected in the grain refinement, reduction of Pb (Ⅱ) growth, increasing the conductivity of passivation layer, reducing the premature capacity loss and extending the life of lead-acid batteries and even had determine the appropriate amount [12].
Results show that, after adding the rare earth alloys with excellent performance, a large number of experiments proved the feasibility of rare-earth joined.

So that in one year the number of egg shells increases into waste that has the potential to cause air pollution due to microbial activity in the environment [9].
This shows that bagasse and eggshell powder as fillers greatly affect the interatomic grains where the atomic pores are getting bigger.
The Correlation of the Absorption (α) Coefficient of Sound with Frequency Of the three samples A5, B5, C5 in the composition (48:48:4) with 20%, 25%,30% resin, it showed that the formation of non-homogeneous particles at a higher frequency resulted in fluctuating coefficients resulting in uneven grain size and voids in the sample. .
For sample B5 on 25% resin with added resin that fills the pores (cavities) between the grains that fill the pores of the structure.