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Since the founding of New China, due to the various factors and social reality, China has implemented the policies of grain center for a long time.
A large number of fertilizer and pesticides are applied in order to achieve the purpose of increasing production.
These approaches make China’s grain output are increasingly depend upon chemical pesticides and other modern inputs.

Neither any columnar grains nor any round grains were recognizable, owing to the nature of the multi-layered nanocomposite film.
The nitrogen and carbon line profiles of the film are not distinct, because of their low atomic number.

According to the Sherrer equation, the grain size along (211) direction of the as-prepared HAp nanoparticles is calculated to be 10 nm.
Also, it is observed that the coating has no loose particles stacking, different from that using electrophoretic deposition technique which generally possesses a quantity of isolate grains disorderly piling up one another.
From Fig.6a to Fig.6b, it can be seen that the number of microholes in the coatings decrease when the deposition is under the hydrothermal condition.

Table 2 reports the data on the fatigue life (number of cycles to failure) for the two types of specimens.
High magnification images of fatigue crack initiation site for sample A (a) and B (b), and optical image for the corresponding macro-segregation on the cast surface (c) The optical micrograph (Figure 4c) shows that the structure on the cast surface is composed of a large fraction of eutectic constituents as compared to Mg-rich grains.
The quantitative EDS analysis on the local composition of these eutectic-segregated regions showed that the percentage of Al is much higher in the Mg-rich dendrite grains as well as in the eutectic regions as compared to the corresponding constituents in the locations in the interior microstructure without segregation.

Fig.2 The original cast microstructure of reformer pipe (a), riser (b) and low collecting pipe(c) The cast microstructure of reformer pipe of Hk40 is consisted of austenite and eutectic in grain boundary of the austenite.
It can reduce effectively the stacking fault energy and improve the high temperature strength of riser pipe by adding Cobalt [4], and its cast microstructure is austenite and eutectic like skeleton in grain boundary[5].
The secondary carbides of riser pipe are small and scattered in beginning, but they can aggregate into large block and their number reduces with temperature and time increasing, its property will reduce[4, 5].The microstructure of riser pipe used for design cycle is good, its secondary carbides are small block and its state of microstructure is equivalent to medium-term aging shown in figure3b.

. %) has residual pores at grain boundary of hard phase (W).
Acknowledgements This study was supported by Universiti Sains Malaysia (Incentive Research grant number 1001 /227/ PBAHAN/8044001) and University of Omar Al-Mukhtar.
SEM micrographs of raw materials: (a) W powder, (b) Cu powder, and (c) Co powder Cu matrix W grain Peripherals porosity (b) (a) Fig. 2.

Adding a certain amount of raw material to the glass batch, and melt at high temperature after mixed uniformity thoroughly, then molded the melt homogenization glass liquid, the glass shaped with the whole forming methods annealed and then nucleation and crystallization at a certain temperature to get the fine grain size and uniform structure of glass-ceramics products.
At first,the basic glass is heated to the nucleating temperature Tn(n---nucleus) of the crystallization nucleus after the annealing, and holding for a period of time following until a large number of stable crystallization nucleus appeared, then the temperature was raised to the crystal growth temperature Tc(c---crystal) and make the crystallization nucleus in the glass become to the glass-ceramics with crystal of submicron and even nanometer grain size.

On the other hand, AZ31B has the equiaxed α-Mg phase and its average grain size was about 15 µm.
Number of Cycles to Failure, Nf ● MgZn2Y2 [room temperature] ■ MgZn2Y2 [523K] ◇ AZ31B [room temperature] not failed the striation-like-pattern forms by activating basal slip in front of the crack.
The region size corresponds to grain size in the AZ31B.

Up to now, a number of techniques like pulsed laser deposition, atomic layer deposition, metal organic chemical vapor deposition (MOCVD), thermal CVD, spray pyrolysis, Sol-gel. and r.f. puttering have been successfully applied to deposit ZnO thin films [6,7].
The grain size (t) of the films correspondingly to 002 peak FWHM can be estimated by Scherrer's formula: t=0.9λ/β Cosθ where λ is the X-ray wavelength(1.54Å ) and β is the peak of FWHM.
The average grain size of the ZnO films at 300 o C is about 30 nm.

Carbothermal reduction-nitridation (CRN) is an attractive method for manufacturing nitride powders with controlled grain morphology because of its endothermic reaction.
Recent studies of rare earth and Ca-� sialon systems have developed elongated grain structures, rendering materials with both high hardness and high toughness.4),5) In general, Ca-� sialon ceramics are produced by sintering a powder mixture of Si3N4, AlN and CaCO3.
We found that the synthesized Ca-� sialon powders had a ball-like morphology of 200 to 500nm in diameter, which was greatly different from the Ca-� sialon powder synthesized under similar conditions using different starting powders.4),5) Furthermore, FESEM observation in Fig. 1(b) indicates that the balls were actually hollow spheres and composed of large numbers of very fine particles of 10 to 30nm in diameter.