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The grain size, d, was defined as 1.56 times the average area-equivalent circle diameter of grains on polished sections.
The pockets of the glass phase located mainly at multiple grain junctions and some pockets lay along grain boundaries.
As presented in Fig. 4, the radial crack was observed to pass through multiple routes: the zirconia grain (z), the zirconia grain-boundary (z/z), the interface between the zirconia grain and the glass phase (z/g) and the glass phase (g).
Saturation in Fz/z appearing for Vg ~5 vol% can be related to a decrease in the number of zirconia grain-boundaries in unit volume.
This result also means that the strength against crack propagation is lower in some grain-boundaries and in the interfaces than in the matrix grains.

Performance Evaluation of Quality Drying in a Natural Convection Grain Dryer S.
In the current scenario, drying through “natural convection grain dryer” is an important alternative.
This paper proposes the development and evaluation of the natural convection grain dryer in drying performance of paddy.
This paper presents the performance of the natural convection grain dryer.
Variation of time, number of batches of paddy dryed and highest temperature.

As can be seen from Table 1, with the increase in the amount of Ni doping I(003)/I(104) decreases, which means the gradually the increasing number of ion displacement.
But then part of the Ni2+ turned into Ni3+, which leads to the increases of the number of current carriers, and Raman peak intensity decreased.
All grains of samples were under 1μm, 500 nm approximately.
The sample c shows that the existence of several crystal blocks in micron sized in the grains in local non-uniform.
Acknowledgments This work was supported by the national innovation experiment program for university students that the number is 35, the Jilin Province Science and Technology Development Plan Project No. 20090533.

The distribution of the grain of samples A-1# is uneven, and abnormal grain growth appeared in the samples.
As seen from Figure. 2 the grain boundary in the sample B-4# is fuzzy and the grains can’t grow up completely.
Comparing Fig. 2 (B-1#) and (B-4#), the grains in (B-4#) is smaller.
The varistor voltage of the sample decreases with the increase of the TiO2 grain size, According to Eq.1 : V1mA=N·Vb (1) where Vb is the varistor voltage of one grain; N is the average number of grains in the sample.
On the other hand, the sintering temperature increases that can generate more liquid, so as to promote the sample sintered and the grain growth, and then grain size becomes large, which makes the average number of grains N reduce.

But the sediment stability of FMA may deteriorate if the grain size of abrasives is bigger, and the situations may further deteriorate with the increase of its grain size (Fig. 1).
First, put sodium dodecylsulphonate into the pure water and heat the solution till the sodium dodecylsulphonate is completely dissolved, then add respectively carbonyl-iron particles, anhydrous ethyl alcohol in turn, next add green SiC of grit 45#(about 355µm, numbered as No.1), 80#(about 180µm, numbered as No.2) and 120#(about 125µm, numbered as No.3) into the solution.
Especially when the grain size is larger than 355µm (mesh number 45#), the sediment stability deteriorate rapidly, which may seriously affect the application of FMA in the finishing process. 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% 0 4 8 12 16 20 24 Sedimental Volume Percent Setting Time/hour No.1 No.2 No.3 Fig.1 Sediment stability of traditional FMA with different abrasives grain size In order to improve the sediment stability of FMA with larger abrasives grain size, we replace sodium dodecylsulfonate with polyacrylic acid (PAA) as surfactants, and some nanometer SiO2 powder are added as additive.
The preparation method is to put polyacrylic acid into the pure water first and give the mixture a enough stir, then use NaOH, HNO3 to adjust pH of the solution to 8 to 10, next add a certain amount of nanometer SiO2(about 10 to 20nm) and disperse it by stirring for about 1 hour, finally add carbonyl-iron particles, and add respectively green SiC of grit 45#(about 355µm, numbered as No.4), 80#(about 180µm, numbered as No.5) and 35#(about 500µm, numbered as No.6) into the solution.
It also can be seen from Fig.2 that even the abrasive grain size be increased to 45# (about 355µm, numbered as No.6), the sediment volume percent of FMA with nanometer SiO2 still keeps quite low (<15%).

In the following discussion, length and volume are expressed in number of grid points (g.p.) and time in the dimensionless time (s').
The total number of subgrain is about 23000.
In order to reduce the total number of orientation variable, Q, six groups of grains were involved.
The total number of subgrain is about 23000.
Thus, it is more difficult for the grain boundaries to escape from the particles, since all of the driving pressure for grain boundary movement is removed once a grain boundary is straight.

The crystal grains of matrix resemble equiaxed ones.
In this study a new kind of in situ particle reinforced aluminum matrix composites reinforced by in situ AlTixZry (x,y means the undetermined atomic number) particles are synthesized by the direct melt reaction between potassium fluorozirconat, potassium fluotitanate and molten aluminum.
In fact the grain refining effect of Al3Ti0.4Zr0.6 particles take effect through peritectic reaction, just as shown in Eq.(4).It is an efficient way to fine grains.
Fig.3 The grain sizes of composites without and with electromagnetic field.
All the crystal grains of matrix in Al-Ti-Zr composites resemble equiaxed ones.

Furthermore, the b grains and subgrains are surrounded by non-equilibrium grain boundaries.
The needle-like a precipitates are completely refined to a nano-grained.
The equivalent strain, εeq, was estimated [3] using the following equation; εeq=2πrNt3 (1) where r is the distance from the specimen center, π is the circumference to diameter ratio of a circle, N is the rotation number, and t is the specimen thickness.
Cellular activity of bioactive nanograined/ultrafine-grained materials.
An investigation of grain boundaries in submicrometer-grained Al-Mg solid solution alloys using high-resolution electron microscopy.

(g) Ratio of the intensities I of the (111) and the (220) Bragg reflection of pure Ni (squares) versus the number of F&R passes.
In addition, the average layer thickness (thick grey curve) is also indicated as a function of the number of passes.
The numbers indicate hardness values in GPa, gray color indicates results from the literature.
The white line indicates the position of the grain boundary between the upper grain (in <100> orientation) and the lower grain.
An extremely high number density of Al-nanocrystals with a size about 12 nm develops within the amorphous matrix during HPT at room temperature.

Ferroelectric BaTiO3 is a perovskite, ABO3, and this material is used for a number of electro-optic, electromechanical, and dielectric applications.In addition, BaTiO3 has been widely used in electronic devices, piezoelectric transducers, ferroelectric thin-film memories, etc., but the largest commercial markets are for positive-temperature-coefficient resistors (PTCR) and multilayer capacitors (MLC) [1].
The brick-layer model approximates the microstructure as a set of cubic grains separated by grain-boundaryplanes.
The resistive contributions of the grain and grain boundary can be represented by an arrangement where the entire grain region forms a single layer (βL), and the entire region of the grain boundary forms another single layer (αL).
From these data, it is possible to estimate the thickness of the grain and grain boundary by only knowing the average size of the grain [Fig. 3(b)].
Resistivities of the grain and grain boundary at 40 °C and the estimated thickness of the grain boundary.