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Meanwhile, Shaanxi Province had no advantages in the supply of feed resources, with the per capita grain production below the world average in 2010.
Qinghai Province had no good foundation in hog farming and had inadequate rural labor forces, with the per capita grain production less than 200 kg/person in 2010.
Hainan Province also had no good foundation in hog farming, with the number of large-scale hog farms about 9000 in 2010.
Besides, Hainan Province also had inadequate rural labor forces, and its per capita grain production was only about 200 kg/person in 2010.
Tibet had a poor foundation in hog farming and had inadequate rural labor forces, with the number of slaughter hogs less than 0.2 million head and the number of large-scale hog farms only about 150 in 2010.

In the Gravina Calcarenite, two main members are recognized on the basis of the relative abundance of skeletal or lithoclastic grains [17].
Moreover, each sample has been cut in the laboratory in order to obtain a number of subsamples for physical and mechanical tests, according to European Standard rules.
At each point, grains (skeletal or lithoclastic), cement, matrix and voids are briefly described, recorded and classified.
It is a bioclastic calcarenite, with moderate sorting, fine to very fine grain size and locally with a micritic matrix.
It consists of well-sorted and rounded grains, with medium to fine grain size; the abundance of components is higher than 60% (Fig. 3b).

SEM (evidence of scale spalling) Recently, a number of efforts were undertaken to evaluate the stresses generated during oxidation of 'alumina formers' and stress-induced strains [9, 11, 12, 14-23].
Moreover, in some cases the new oxide is formed within the scale along its grain boundaries which results in its lateral growth and, consequently generation of compressive stresses in the oxide layer [26].
This, as recently proposed [12], may activate the substrate grain boundary sliding which leads to the locally uneven substrate surface which, in turn, causes cooling-induced convoluted scale-substrate interface and/or scale morphology as well as cracking and/or spalling of the scale initiated at the edges of uplifted substrate grains.
This effect can be responsible for the observed oxide formation along the oxide grain boundaries.
Yttrium is the best recognized alumina dopant which segregates at grain boundaries, and through this process changes its microstructure from equiaxed to columnar, affecting the scale growth mechanism [30-32].

Introduction The titanium alloys have a number of advantages: low density, very favorable ratio of strength to density, high yield stress, resistance to high temperatures and high corrosion resistance and also biocompatibility [1].
Grade 3 was grain microstructure.
Furthermore, it then causes recrystallization of defect microstructure during the dehydrogenation stage to grain refinement. 2.
Kaibyshev, Grain refinement in commercial alloys due to high plastic deformation and phase transformations, J Mater Process Tech, 117 (2001) 300-306
Szkliniarz, Effect of cyclic heat treatment parameters on the grain refinement of Ti-48Al-2Cr-2Nb alloy, Mater Charact 60 (2009) 1158-1162

The increment of yield strength is result from the increment of the grain aria.
Prior β grain boundaries is interrupted, but it can be seen clearly yet.
When deformation is increased to 50%, prior β grain boundaries could not be found.
This shows that it has important influence of deformation on breaking β grain at weld zone.
As mentioned above, the forging temperature and the amount of deformation act apparently on grains fine and uniform.

Introduction Nanocrystalline ceramics can greatly enhance the hardness, toughness and superplasticity of ceramics, and greatly change their electronical, mechanical, magnetical, thermal and optical properties due to grain refinement and the increasing number of grain boundaries, and as a result have become a hotspot of materials science [1-2].
Since the nano-sized powder will grow into large grains quickly during the ordinary sintering, it is difficult to obtain nano-sized ceramics.
The grain size and the agglomeration of the powders before and after the vacuum heat treatment were observed by means of transmission electron microscope (TEM).
It can be seen that there is no obvious change for the grain size which is about 30nm.
When the grain size is smaller than 50 nm, the van der waals force will be rather strong and the agglomeration of particles will come into being.

From the microstructure analysis, when the laser power is 1.2kW, most CBN particles are not melted, but unevenly distribute in the coating and a large number of accumulation generated.
When the laser power is 1.6kW, CBN grain distribute evenly in the coating and most continuous block are precipitated which can combine with substrate strongly.
When the laser power is low, though most CBN particles can retain, molten pool energy vary widely in different areas of the coating lead to the high temperature melt convection ability is weak, so that the CBN grains distribute not evenly and the melt may be due to the low power weak bonding strength between the coating with CBN grain and results in the decrease of the wear resistance of the coating.
When the laser power is too large, on the one hand it will increase the dilution effect of matrix and on the other hand it also can make CBN grain melt or reaction to generate TiB2 and TiC and CBN and bonding strength of titanium alloy substrate can be improved, but the CBN grain is less, reduces the coating hardness and abrasion resistance.
Therefore from the CBN distribution in the coating and tissue morphology experiment adopts 1.6 kW laser power can obtain good adhesive force and CBN grain distribution uniform coating.

Reducing the grain size of Sm2Fe17 powders can improve the nitriding process and increase the coercivity of the synthesized Sm2Fe17Nx.
The XRD patterns were very broad due to refinement of the grains.
From the calculation of the XRD patterns, the grain size of the synthesized Sm2Fe17 flakes was about 18 nm.
These diffraction peaks were still very broad, which indicates that the grain size is still maintained in nanoscale.
It is well known that nanocrystallite has a large number of grain boundaries due to its ufltrafine grains.

It is important to point out the fact that the grains size of pearlite is variable.
The grains form locally a fine distribution (5-6 points on the scale of the grain size standardized norms), alternating with areas where the pearlite grains are middling increased (3-4 points on the same scale).
An important detail of the structure is related to variable grain size of pearlite.
They appear either like a finer morphology, either like increased grains suggesting a local overheating phenomenon.
Andrei BERBECARU is supported by the Sectoral Operational Programme Human Resources Development (SOP HRD), financed from the European Social Fund and the Romanian Government under the contract number POSDRU/159/1.5/S/137390/“. 2.

Hydrogen-induced fracture can proceed either in an intercrystalline or in a transcrystalline fashion relative to the prior austenite grains.
Intercristaline hydrogen embrittlement shows the following characteristic features on the fracture surface: intercrystalline subsidiary cracks (yawning grain boundaries), ductile hair lines and micro pores at the grain boundaries [4,8].
The cracking core appears in areas where failure is blocked by sediments, grain boundaries or hydrogen accumulations.
Although the fracture is ductile, a great number of spherical type of sulfide discontinuities (fig. 3a) and slag inclusions (fig. 3b) were observed.
Due to this behaviour, the fracture surfaces reveal fine dimples covering the grain boundaries.