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Introduction A number of technologies have been developed over the last three decades, mainly in a laboratory environment, to take advantage of the unique behaviour of semisolid slurries.
It has thus been investigated by a number of workers [ 4,5,6,7].
As holding time increased, the grain size increased about 10% as expected.
At the same time, the sphericity of primary α-Al grains increased from 0.597 to 0.701.
The liquid phase surrounding the grains results in the decrease of apparent viscosity with higher formability.

The number of aggregations increased with increasing processing time, and showed wide grain size distribution simultaneously, which effectively increased the light scattering and decreased the grain boundaries to suppress the electron recombination.
After zinc acetate aqueous post-treatment, some aggregates were formed in these photoanode films, and the number of aggregates increased with the increasing of post-treatment time.
The aggregates not only enhanced the surface roughness to obtain higher dye absorption, but also decreased the number of grain boundaries to reduce electron recombination. 
On the other hand, the formation of submicrometer-size aggregates after post-treatment not only increase light scatting, but also reduce the grain boundaries to improve electron lifetime.
However, at longer post-treatment, although the R2 is lower, the Jsc and η decrease because the submicrometer-size aggregates reduce the grain boundaries, while more aggregates will decrease the dye absorption.

Presence of refined grains and dynamically recrystallized grains were observed.
It clearly shows the grain refinement and generation of lamellar and g phase with recrystallized grains.
This can be due to generation of large number of nucleation sites resulting in higher % of dynamically recrystallized (DRX) grains, but of smaller size due to insufficient time for growth of nuclei at higher strain rates.
Upon isothermal hot working, dynamic recrystallization occurs and results in a mixture of fine equiaxed grains and deformed elongated grains.
Deformation upto 50% results in fine grained recrystallized grains along the grain boundaries and lamellar colonies inside the grains.

Due to the raise of the mechanical load, either portions of several grains break off (grain breakage) or the bonding of the grains fails (pullout of whole grains) [3].
In hydraulic power systems, the number of particles circulating within the hydraulic fluid is limited to a level depending on the sensitivity of the parts of the system to the contaminant [9].
Tab. 1: Sets of experiment Set number.
The corundum particles clogged in the pores of the wheel decrease the effective number of cutting grains.
The local break-away of grains leads to an increasing waviness of the machined surface.

In Mg-4%Al-(5~7)%Zn alloys most of the grain boundary phases were found to be Mg-Al-Zn while in Mg-6%Al or Mg-8%Al based alloys the MgAl-Zn phase coexisted with Mg17Al12 at grain boundaries.
Introduction A number of researches have been conducted to develop the heat resistant magnesium casting alloys that possess excellent casting ability, corrosion resistance and mechanical properties.
However, a large number of newly developed alloys have not been extensively used for practical applications because they often include expensive alloying elements or show relatively low casting ability.
In Mg-4%Al base alloys most of the grain boundary phases were observed to be Mg-Zn-Al and Mg17Al12 phase were not easily found.
When Al content increased to 6% or higher, Mg17Al12 phase as well as the Mg-Zn-Al phase coexisted at the grain boundary.

In addition, a large number of B elements additions can dramatically improve the dynamic storage modulus.
Mo and Al addition led to thick grains (see Fig. 3(a) and (b)) while alloys with B addition exhibited fine particles and uniform structure (see Fig. 3(c)), since B is a typical element for grain refinement.
As for B element, it could dissolve into the matrix lattice of Ti alloy, leading to grain refinement, when the doping content is small.
These precipitate would impede crystal growth, increasing the number of grain boundary.
In addition, most of the oxygen atoms would aggregate at the grain boundaries, decreasing the number of oxygen atoms that would participate in Snoek relaxation process, and thus making the damping values decreased.

The model of gradient ceramic tool material is symmetrical composition distribution, and the compositional distribution n and layer number are 1.8 and 7, respectively.
CaF2, as the nano-lubricant and the average grain size is 20nm.
The dark grain is Al2O3 and the white grain is Ti(W,C).
The white grain in layer 1 was more than layer 2, and the dark grain was the opposite.
According to the Hall-Petch relation, the grain size lower, the flexural strength higher.

Introduction With the development of society, household equipment gradually to the trend of electrification, electrical equipment caused by fire is also increasing year by year, the number of electrical fire which has happened in all kinds of fire takes the first place.
According to the Fire Bureau of the Ministry of Public Security Fire in China Statistical Yearbook data show that: the 2008 national total of 133,000 fires, the electrical fire of 40 000 cases, accounting for 30.1% of the total number of fires [1].
In this respect in China started late, but also have been developed in recent years a number of major difficult cause of electrical fire.
As a result, its microstructure is composed of thick equiaxed grain (figure 3).
It is according to the size of the over current, over current length and different, its organization from the start of the processing state become equiaxed grain (figure 7), as over current continues growing grains, the essence of this change is due to the increase of over current and continuous time, make its temperature of the wire; Instantaneous large current will cause local overheating and fuse wire, and the whole conductor is uniform grain grew up.

Secondary α phase precipitated along β grain boundaries (αGB) and inside β grains as dot shape initially, when aged at 500oC.
A number of comprehensive studies has been carried out on the evolution of α phase during hot deformation, heat-treatment and aging following cold pre-deformation in β titanium alloys [8-12].
This work studies the secondary α precipitates nucleation and morphology evolution of hot-rolled Ti-7333 alloy in low-temperature aging, which introduced a large number of defects.
It can be seen from Fig. 2 that there exists many micron recrystallization grains (2～3μm), with equiaxed α phase distributed at triple junction(TJ) and β grain boundaries.
Fig. 5(c) and (d) show the number of dot-shaped secondary α phase increased, and subsequently connected as line, when aged for 5minutes.

These particles consist of rounded WC grains with an average diameter of about 0.18 μm, surrounded by cobalt.
The grain size in the particles depends on the cooling rate, which reaches 109 K/s during SE.
The measurements showed that the average diameter of the formed WC grains is approximately 0.18 μm, which is significantly smaller than the average grain diameter in the initial alloy (1.6 μm).
Predicting an increase in CO concentration to 100 %, we fed into the furnace a volume of CO2 (2), the number of moles of which is equal to the number of moles of carbon that must be removed.
The average grain diameter increased to 0.43 microns.