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Cooling rate significantly influences the grain size as well as the grain growth kinetics.
But the number of research articles directed towards the atomistic studies of solidification of metals/alloys/composites are limited in number [2].
The embedded atom method has been extensively used to study the properties of a large number of metals.
The grain growth kinetics has been investigated keeping the system at temperature 853 K for a long duration of time.
Therefore, for a practical cooling rate of 1 K/s and a system size of few cm3, a greater number of atoms will be accumulated at a particular location to form grains at the initial stage and rearrange themselves in the later stage to form more stable structure.

To facilitate the measurements of strain gradients inside the grains, a specimen with very large grains has been chosen.
The procedure of recrystallization and grain growth was optimized in order to obtain grain sizes of about 5 mm.
Sample with large grains.
A meshed sample with its grains numbered.
Grain 3: a.

Microstructure observation indicates that Yb-α-sialon consists of equiaxial grains, but when increasing the radius of the doped cations, the elongated α-sialon grains form and the aspect ratio of grain increases slightly.
Some elongated α-sialon grains with grain core were found.
Surrounding the grain core, some misfit dislocations were seen.
In order to control the nucleation and obtain elongated α-sialon grains, some α-sialon seeds have been added into starting powers and effects of the size, morphology and number density of seeds have been studied [7].
Yb-α-sialon is entirely composed of equiaxed grains.

The damaged area and the number of deformed grains, which could be identified as dark reflection in optical microscope images was evaluated at certain numbers of loading cycles semi-automatically by using an image analysis software.
Grain size (D), average number of grains per cross section (ζ), ultimate tensile strength and Young's modulus (E).
The small number of deformed grains in the type A copper can be partially attributed to strengthening effect as described by the Hall-Petch effect where due to a higher density of grain boundaries in the films with a smaller grain size, the dislocation movement is hindered.
This effect is mainly due to a larger increase in the number of deformed grains with the type B copper.
This is especially pronounced with the thin 5 µm films where the deformation density with the type B copper is twice as high at 150◦C compared to room temperature while there is only very little increase in the number of deformed grains in the type C copper.

The growth grains is directly related to diffuse mass transport along grain boundaries from the regions under the compressive stress to condensate at the surface and combines with adjacent grains and forms secondary grain growth[4],[5].
With the grains growing, the mean surface roughness has been increasing significantly.
For DC magnetron sputter deposition, substrate is only as a carrier to receive the sputtered atoms, and the number of sputtered atoms is merely relationship with energy and density of Ar+.
That is the characteristic of the substrate, such as substrate temperature, can not determine the number of sputtered atoms.
The grains are growing and the surface is performing rough with heating the substrate.

The size of liquid droplets was increased while the number of liquid droplets was decreased with increasing the isothermal holding temperature and time.
Additionally, with the increase of isothermal holding temperature, the liquid film becomes more and more thicker, and the number of adjacent grains will be decreased.
Therefore, the size of liquid droplets is increased while the number of liquid droplets is decreased with increasing the isothermal holding temperature and time.
Coarsening kinetics of solid grain.
Meanwhile, the size of liquid droplets is increased while the number of liquid droplets is decreased with increasing the isothermal holding temperature and time

Lattice sites having the identical Q number are considered as a grain, and a grain boundary segment is defined to lie between sites of different Q number.
NA and NB are the sites number of phase A and B, NC is the smaller sites number of that of phase A or B. δQiQj is Kronecker delta function, Qi and Qj denote the grain orientation state of the neighboring sites i and j.
Some grains significantly shrink, at the same time, some grains grow.
It can also be obviously seen that the number of nano-particles inside the matrix grains decreases with an increase in the size of nano-particles, this result is consistent with experimental observations that larger-sized nano-particles prefer to locate on the grain boundaries and smaller nano-particles often lie within matrix grains.
It can be found from Fig. 4 that the grain growth exponent decreases with increase of mean grain size for a given curve and to nearly zero when grain growth is pinned.

In situ tensile testing of ultra fine grained Pd and Pd-Ag alloys K.
This latter approach was used in our group to improve the strain hardening ability in a number of Pd-Ag alloys processed by high pressure torsion (HPT).
Results and discussion Grain scale analysis.
To further explore the problem, the in situ tensile testing was carried out for HPT-processed Pd and a number of Pd-Ag alloys to observe their deformation behaviour.
Fecht: Grain refinement and deformation behavior of ultra fine grained Pd and Pd-Ag alloys produced by HPT.

Qiu proposed the concept of coarse grain effect.
He believes in the process of fine particle flotation coarse grain to fine grained with a carrier, mediation and coagulation effect.
Powerful bubble washing way is beneficial to overcome the fine grained inclusion of gangue and nonselective reunion between mineral grains.
Microvesicles precipitation method is varied, such as in the pulp surface suction pulp caused negative pressure generated bubble, the electrolysis of water produced large numbers of micro bubble.
The research of fine grain carrier flotation hematite mechanism [J].

Due to the grain storage located in remote areas, the existing Monitor System for Grain is just monitored locally，and it is difficult to achieve remote monitoring.
Introduction Grain storage monitoring technology is one of the key technologies of scientific grain protection.
This system deploys a large number of wireless sensor nodes in the grain depot, which sample the grain temperature.
This system realizes remote temperature monitor of grain depot and data processing, and provides guarantees of scientific management of grain for administrators.
This system has been deployed in the actual grain depot, realizing the function of remote temperature monitor of grain depot.