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The few nuclei and low diffusion lead to the formation of large grains.
Thus, the size of grains in high temperature micaroemulsion system is large.
This result indicates that the smaller grain size FePO4 has a higher electrochemical activity for lithium insertion /extraction.
Results show that the grain size of FePO4 has a great effect on the specific capacity of the cathode materials.
Fig.5 (c) shows the discharge capacities versus cycle number curves of pure FePO4 sintered at 380 ℃ and 460 ℃.

Classification of Emotional Polarity of Product Reviews Classification of emotion is divided into two levels of research and fine-grained. 
Coarse-grained study is a paragraph-level comment.
Fine-grained research is to extract “Product Features - views on”. 
Through the analysis of a large number of product reviews text, we find that users can not only concerned with the overall quality of goods. 
To obtain a large number of comments, dig out the product features attributes frequently concern.

In this figure thedispersed Si3N4 phase is located between cBN grains and filling up the voids and pores in the composites.
As shown in Fig. 2, many grain are pulled outs and a few porosities are observed on its fracture surface.
In Figure 2 one should also note evidences of intergranular fracture, which happens separating crystalline grains that form the cBN particles.
As can be seen in Table 1, increasing the number of cycles results in a higher degree of transformation of α-Si3N4 to β-Si3N4.
Si3N4 composition after sintering process Number of cycles Wβ (%) 1 41.4 2 57.9 3 73,4 As shown in Table 2, composites display an increase in density with sintering cycles.

As shown in Fig.1 (a), the fine microstructure was visible; the average grain size was roughly 20 μm.
A great number of precipitations which are small dispersion in morphology are observed in the specimens.
The grain size and the precipitations will play an important role in the mechanic properties and corrosion behaviors for the Mg-7Gd-5Y-1Nd-0.5Zr alloys.
The corroded pits without corrosion products appear to have been formed by a number of larger pieces.
For specimens at RH=90%, with the concentration of CO2 increasing, the number of the pits increased and gradually appeared as a honey-comb distribution (Fig. 3C).

It can be seen from Fig.1 that many pits which may result from the crystal grain breaking during the fracture mode machining of the SiC ceramic material and some scratches which are the traces left by the ductile mode machining rise on the machined surface.
It can be seen clearly from Fig. 2 that many fractures of crystal grain breaking exist on the machined surface and some plastic build-ups which usually occur during processing of the cutting metals lay on both sides of the scratches.
In addition, it also can be seen from Fig.1 that the number of the broken pits on the lapped SiC ceramic surface gains while the number of the ductile scratches falls and the surface quality gets worse when the lapping pressure increases.
The SiC ceramic workpiece surface lapped by the abrasive of W7 (seen in Fig.4b) is smooth too, but the number of broken pits increases.
The cutting depth of the abrasive grain decreases and hence the scratches get shallow as the grit size decreases.

Material and methods The selected spruce wood [6] had required physical and acoustic characteristics (low density, high radiation of sound, high speed of sound along the grain) for the top plates of violin.
The dynamic modulus of elasticity [Pa] along the grain was calculated using the equation: (1) where[m] is length, ρ [kg.m-3] is density and fr [Hz] is the fundamental resonant frequency.
The acoustic constant [m4.kg-1.s-1] was calculated from the equation: (2) where c [m.s-1] is speed of sound along the grain.
From Table 1 is evident that with the increased number of Na2SiO3 layers: the density of test specimen increased; dynamic modulus of elasticity increased up to the third layer (however, it decreased after the application of further layer, but not to the original value; acoustic constant decreased with the increased number of layers.
Tab. 1 Physical and acoustic characteristics of spruce wood (SW) Layer –concentration n – number of spec.

In addition, because there are large number of sub-marginal ores resource, if the ores is abandoned in the mining process, it will pollute environment; else if be retrieved, the ore grade to the concentrator will surely be reduced, and the concentrate grade and metal recovery will be greatly affected.
If the low grade iron ores are separated after grinding without preconcentration, which will produce a large number of fine-grained tailings with more environmental pollutions, and increase the costs of tailing processing.
It can reject a large number of tailings before grinding, increasing productivity and upgrading the feed and reducing production cost.
Due to the limitation of separation principle of dry magnetic separation (DMS), there are many difficulties to treat the fine-grained ultra low grade magnetite by DMS, such as large amount of tailings, high operating cost and much loss of magnetite in the tailings.
At present, there are many methods to utilization of the tailings, for example, large quantity of waste rock is usually used as building material, and fine-grained tailings are used to make ground brick and cement material, besides some are also made as new wall materials. 4) Ecological environment protection for ultra lean magnetite resource exploitation land should be valued.

In general, this issue includes a great number of parameters and variables.
It is also possible to obtain very fine grained structures by a suitable choice of temperature.
By a suitable choice of temperature it is also possible to obtain structures with very fine grain.

Furthermore, with the technique of mechanical alloying, the parameters of the grain size and the composition of the alloys can be controlled better [11, 12].
Fig.3, shows that the grain formation results from an agglomeration of smaller particles.
Scaninig electron microscopy (SEM) of Cu84Al12 Ni4 grain.
Consequently, the inter-layer spacing decreases and the number of layers in a particle increase.
The mean size of the grains did not present a large variation after 30h of mechanical milling.

Common to systems that have the property of self-organization is the interaction of a large number of subsystems, leading to collective effects with characteristic spatial scales that significantly exceed the size of individual subsystems [5, 6].
As the number of cycles increases, the dislocation structure of steel gradually becomes more complex.
Austenitic grain boundaries in 20Kh steel after five cycles of thermal cycling in the temperature range of 850-600 °C a - ×400, b - ×1200 At optical magnification, the smallest fragments of the dissipative structure are obtained very similar to large-scale objects.
At a higher magnification, a large number of border bends were detected on the same grain boundary sections, since small increases cannot account for small bends.
It is known that the method of fractal analysis has been used in materials science for a number of years [10 - 11], but in these works the object of research was the grain structure or porous materials.