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In industrial, due to its high bandwidth, it has obvious advantages when used in coarse-grained materials testing and high-precision thickness measurement.
In the industrial field, because of its high bandwidth, it has obvious advantages when used in coarse-grained materials testing and high-precision thickness measurement.
Acoustic impedance of polymer piezoelectric ceramic is 2.6 × 107kg/m2s, and the acoustic impedance of air is 4.3 × 102kg/m2s. 5 power differences will lead to a large number of radiation losses on the surface of the piezoelectric ceramic.
In industrial, because of its high bandwidth, it has obvious advantages when used in coarse-grained materials testing and high-precision thickness measurement.

However, the presence of a small amount of grain atoms formed on the surface was confirmed using SEM measurement.
The Plan-view SEM images for Si/SiO2 multilayers as shows in Figure 6(a) it has been observed the smooth Si surface with the presence of a small amount of grain atoms formed on the surface with diameter between 64-116 nm.
The AFM and SEM result has been observed that the increasing of the deposition time allows more silicon attach to substrate and form the nanodots, thus increasing the number of atoms as well as carriers.
The decreasing of XRD intensity at long deposition time related to the decreasing of the silicon crystal quality, which confirmed the reduction of grains size.

Optical microscopy showed the formation of a grain size refined morphology in the heat affected zone and fusion zone.
The corrosion current density (icor) was calculated using the Eq. 1 [10]: (1) Considering an uniform corrosion, the corrosion rate [mm year-1] was estimated using the Eq. 2: (2) Where PA is the atomic weight [PAZn = 65.37 g mol-1], t is time [31,536,000 s], n is the number of electrons involved in the reaction [nZn = 2], ρ is the specific density [ρZn = 7.140 g cm-3], S is the electrode area [0.785 cm2] and F is the Faraday constant [96,487 Coulomb].
It is well known that reduction of grain size is beneficial to mechanical properties of welded materials.
This modified microstructure, characterized by its small grain size, protects the base metal from corrosion.

L3 shows a smoother surface and presents large number of craters revealing the morphology of the beneath AISI 304 substrate.
Using (220) peak, the grain size of TiN crystals gave an average size of ~ 5 nm.
Average grain size of TiN crystals was found to be ~ 4 nm, while average grain size of Cr2N crystals was ~ 10 nm.
Average grain size of TiN crystals was ~ 5 nm, whereas average size of Cr2N crystals was ~ 10 nm.
Ti-Al-Si-B-N samples show TiN phase also after vacuum annealing, with average grain size of ~ 7 nm.

. % to aid formation of MgAl2O4 on firing at 1550-1650°C resulted in the spinel phase without any effect of TiO2 on the grains as its presence was limited to the grain boundary regions with impurities like calcium oxide and silica that form low melting phases.
In order to achieve better bonding of the periclase grains by the spinel matrix, oxides that form spinel should dissolve in magnesia at high temperature and precipitate on cooling such that they bond the interface of two periclase grains.
Densification and grain growth mechanisms during sintering of nano-materials have shown that they can agglomerate and coalesce at relatively low temperature [15] resulting in coarsening of the grains.
In the case of having 8 wt. % ferric oxide in the mix, spinel formed using nano-oxides have a lower lattice parameter compared to similar compositions without nano-oxides indicating that there are a reduced number of defects and that the cations are in their preferred site in the spinel solid solution.
Pandolfelli, Magnesia grain size effect on in situ spinel refractory castables, Journal of the European Ceramic Society, 28 (15), 2008, pp. 2845-2852

To meet all the requirements of any given application, a number of factors must be taken into consideration.
The generally recommended sizes are as follows: � 50/60 US mesh - for very hard, fine-grained materials (e.g. flint, very hard granite), � 40/50 US mesh - for hard, fine-grained materials (e.g. granite, basalt), � 30/40 US mesh - for medium hard materials (e.g. marble), � 20/30 US mesh - for easy to machine, abrasive materials (e.g. coarse-grained sandstone).
Which concentration to use depends on a number of factors.
Otherwise the load on an individual grain is correspondingly low, i.e. the grain penetration depth is shallow, which results in polishing the diamond.
Borse: Process for Treating Diamond Grains (US Patent No: 5,035,771, July 30, 1991)

Furthermore, some imperfective puncheon-shaped crystals exist among a large number of whole puncheon-shaped crystals which are about 30-70 nm in length and about 10-20 nm in diameter.
Laser grain-size analysis (Model BT-9300H Laser granularity distributing apparatus and Model BT-600 deconcentrator) was carried out with the triethanolamine as dispersing agent at China University of Geosciences, Beijing.
It is clear from Fig. 4a that plenty of whole puncheon-shaped crystals exist in the powders with about 30-70 nm in length and about 10-20 nm in diameter, and a large number of smaller size puncheon-shaped crystals can be found among the frist type of crystals.
From the calculation results of mullite crystal (JCPDS Card number is 15-776), d(120)= 0.343 nm, d(001)= 0.289 nm and d(121)= 0.206 nm, the angles between these planes are f(120)^(001)= 90°, f(001)^(121)= 40.091° and f(120)^(121)= 49.909°.
Moreover, the SAED pattern of mullite crystal illustrates that the grain has a zone axis of [uvw]=[ 20].

Pauling [12] initiated that ''the radius of an atom reduces with the reduction of its coordination number CN.''
The inner part of the grain has no bond contraction.
Due to the surface bond contraction, the radius of the grain will shrink by a small amount, δR = δna
(3) Where R is the radius of the grain, a is the lattice parameter and n is the number of unit cell layers which perform surface bond contraction [14].In order to examine whether CdS@CH nanoparticles (a) (b) Fig. 2: FTIR Spectra of (a)CdS@CH and (b)Chitosan .
The grain diameter D of the sample was determined using the Scherrer's formula: D =K λ / β Cosθ

Table1 Dimension and numbers of samples Processing project Dimension：thick × wide ×long [mm] Numbers of samples [piece] Planning 19×102×910 30 Sanding 10×102×305 Testing and Evaluation Method.
The testing results showed that defects became more serious and the number of defects was increasing substantially with the feeding speed adding.
It was notable that, just after sanding, if not force to wipe, sample surface would not appear nap, even if wiping the surface along arranged grain direction.
But when wiping some samples along the horizontal grain direction by hand, there were a large number of surface naps.
The machining quality of Mytilaria laosensis and Castanopsis hystri near the sub could be improved significantly through sanding, and planning defects(burr, chipped grain, raised grain, etc ) were significantly removed at the same time, so sanding was a necessary processing for Mytilaria laosensis and Castanopsis hystri machining after planning.

These precipitates contribute to the improvement of mechanical properties by precipitation strengthening [1,3,4] and by grain size control during austenite-ferrite transformation (refinement of ferrite grain size) [1,3-5].
Observations were performed mainly in ferrite α grains.
Figure 2 (c) shows the typical ED pattern of a particle in a [1-1-1] ferrite grain.
Figures 5 (b), (c), (d), and (e) exhibit the size distribution obtained and the number of particles observed for states heat treated at 870°C for 2, 10, 20, and 60 min.
All distributions have the same shape even if the number of observed particles is low for the last PDS (figure 5 (e)).