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The brick has a velvety texture of various colors, with a large number of indentations, roughness and various irregularities.
After this operation, the grain composition of the raw material should be within the fractions from 0-1.25 to 0-0.16 mm.
The equipment should be configured so that the output of the continuous grain composition is close to the densest packaging.
The preparation of raw mixtures with intermittent grain composition significantly complicates the production.
Guaranteed grain composition is easily achieved using pendulum and vortex mills.

In optical and tribological applications, specially, the rough surface of the polycrystalline diamond films with grain sizes in the order of micrometers is the main restriction.
Up till now, a number of CVD methods, including microwave plasma-enhanced chemical vapor deposition, direct-current glow discharge plasma, laser-induced plasma CVD, and hot-filament CVD, have been used to deposit nanocrystalline diamond films.
Bias voltage was usually used to enhance nucleation density and restrain the growth of large grains.
The films comprise fine, compact grains and the average grain size is about 200nm.
The expected diamond band at 1332 cm-1 is significantly broadened, which can be attributed to the low quality diamond present and a small grain size.

The energy-band model of double Schottky barriers formed at the grain boundaries between ZnO grains was proposed [2].
Multilayer-type varistors using a heterojunction of a thin film of ZnO and an impurity layer, based on elements such as Bi and Pr, prepared by pulsed laser ablation have been proposed because varistor voltage can be adjusted according to the number and thickness of the layers [3], [4].
The unique feature of this device is that Co was added into ZnO beforehand to form donor levels in ZnO grains.
It is known that the varistor voltage of one grain of a bulk-type ZnO varistor is approximately 3V [5].
The varistor voltage was lower than that of one grain of a bulk-type ZnO varistor.

Due to the variable number of controlled process parameters, affecting each other, IBAD PLD allows to obtain a wide range of film properties.
Results and discussion It was determined that increasing the target-substrate distance in the range between 20 mm and 135 mm surface roughness of nanocrystalline films decreases from 3.6±0.2 nm 2.7±0.2 nm, and grain size goes down from 600±50 nm to 90±8 nm.
Since the films have a nanocrystalline structure, carriers are concentrated in areas near the grain boundaries.
With increasing temperature of the substrate, a small grain structure is formed, and grain boundaries increase, leading to an increase in resistivity.
The research shows the possibility of controlling the concentration and mobility of charge carriers, grain size and surface roughness of the films in a wide range of parameters by changing the process conditions nanocrystalline ZnO films by IBAD PLD.

From the calculation of Scherer equation [16], the average grain size (d 25°C) of (020), (021), (130) and (002) crystal planes was 2.40 nm.
According to the morphology shown in Fig. 3(a), it could be seen that the grain size was so small that obvious acicular γ-FeOOH could not be observed very clearly.
The average grain size (d 50°C) of (020), (021), (130) and (002) crystal planes, which was obtained by calculation of Scherer equation, was 15.77 nm.
The average grain size (d 75°C) was 20.32nm.
Taking into the account the facts mentioned above, it was shown that the crystal regularity and grain size increased with the increasing of temperature.

In the manufacture of the large scale integrated circuit, the line width and component numbers in microelectronic devices are decided by the super-accurate processing technological level.
Ascertainment of Abrasive Grain.
But the super-lower abrasive grain will cause the temperature raised in grinding processing and reduces productivity.
According to experiments, we choose 400# abrasive grain.
Considering synthetically the factors of work materials, abrasive grain and grinding manners and so on, we selected the higher concentration value of 100% , and the hardness of the slipstone is of J-K (soft 3 - in soft).

Small additions of zirconium can improve the properties of 7xxx series alloys by forming metastable, coherent with the matrix Al3Zr dispersoids, which stabilized the grain structure and prevent recrystallization [6].
MgZn2 111 Al 200 Al 220 Al Ribbon A Alloy A The XRD pattern for the ribbon showed a certain broadening of α(Al) reflections, which is the result of the grain refinement.
In STEM-HAADF image, presented in Fig. 3c, the bright area corresponded the phase enriched in Zn and Cu (in this technique the contrast is sensitive to Z number).
Fine spherical L12-Al3Zr particles stabilize the grain structure of the alloy and prevent recrystallization by pinning grain and sub-grain boundaries.

It is obviously that cubic the spinel structure (ICDD card number 23-1237) phase was indexed in all samples with no sign of other phases being present.
The incorporation of small extent of Na instead of Cu at MC-3 sample leads to significant increasing in the grain size due to the enhancement of ions diffusivity causing crystal growth acceleration.
Besides, the fusion and densification of crystals are responsible for larger grain sizes for both B and C samples.
The EIS spectra for all samples consist of two semicircles; the first semicircle (Rs) originates from the bulk materials (grains), while the second semicircle (Rct) represents the polarization resistance that is created due to charge transfer (electron carriers) through grain boundaries.
Dopping with Fe,Cu,Ni and Na caused fusion and densification of crystals which is responsible for larger grain size, beside an increase in the porosity of spinel structure without any changes in morphology.

Cast forging reduces both the number of processing steps and energy consumption [1-11].
The grain size became smaller until Al-8%Mg as the Mg content increased.
For Al-10%Mg, small grains appeared at grain boundaries.
These small grains might be recrystallized.
The grains in Al-10%Mg were larger than those in Al-8%Mg.

Poor wear properties of gelcasting nanocomposites including sintering additive was caused by degradation of grain boundary properties due to including sintering additives.
Wear behaviors of HIP-5SC1Y and HIP-5SC1M nanocomposites exhibited rough surface due to intergranular-type fracture along the weakened grain boundaries and a part of the formation of wear debris film on worn surface as shown in Fig. 2(b, c).
Coarse wear debris occurred grain cluster chipping due to intergranular-type fracture along the weakened grain boundaries during wear tests.
Smooth worn surface and generation of fine wear debris due to transgranular-type fracture (or grain pitting) caused low friction coefficient of HP-5SC nanocomposite.
Acknowledgements This research was supported by the Pioneer Research Center Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (Grant number: 2010-0019473).