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Through research benefiting the agriculture policy Jiangxi grain cooperatives affect the costs and benefits to help pinpoint stabilize grain production, increase grain production capacity to ensure food security direction.
Stable development of grain production, so that farmers can be indirectly controlled grain costs, increase food revenue.
Benefiting the agriculture policy of planting grain cooperatives cost-benefit analysis In recent years, farmers engaged in grain production in Jiangxi growing enthusiasm, professional big grain acres or more from 2009 to 6969 to 2011 the development of 9319, professional big grain planting area about 335.5 acres of the total acreage 6.7%, respectively, 270 and 16.4 acres increase over the previous year.
Land costs cooperatives calculated according to the actual number of traditional farmers to do the same self-folding rent, are about $ 50
Jiangxi whole number of 17,000 cooperatives (grain cooperatives which nearly 10%), farmers join 190,000, covering 20% of households, total invested 25.61 billion yuan, driven by non-farmers to more than two million members, members generally average household income farmers than non-members more than 25%

This paper focuses on contact pressure between grain and workpiece.
Fig.1 Structure mode Every contact cell includes several KEPYOPTS, and recommends default to fit a great number of contact problems.
In order to simulate the normal force of grains on die surface, the indentation of a symmetric, cone-shape grain with the rough surface is used as the model of the single-grain polishing.
ABC section presents the axial plane of the cone-shape grain with the cone angle 2γ; h is the depth of the grain in the workpiece. there exists a rigid region HBDGH.
Since all acting grains are not on the same plane of the polishing disk, when the force is small, the total number of acting grains is less, and the depth is larger.

The Challenge of Inhomogeneous Deformation in Magnesium and its Alloys Matthew R Barnett Centre for Material and Fibre Innovation, ITRI, Deakin University matthew.barnett@deakin.edu.au Keywords: grain boundary sliding, precipitation control, magnesium, strength, extrusion Abstract It is shown that wrought magnesium alloys display a number of significant types of deformation inhomogeneities.
It has long been known that the difficulty in achieving desired low temperature ductility in magnesium alloys owes itself to the low number of deformation systems/modes in this material [1].
That is, it is quite homogeneous at the grain scale.
This leads to considerable grain to grain heterogeneity, which has a number of consequences.
Such strain heterogeneity occurs when the stress is more evenly shared over the structure and can arise in a number of cases.

The number, shape and size of austenite decomposition and transformation product has important indirect effects．For micro-alloying steel contained micro-alloying elements such as Nb, involving dissolution and precipitation of carbon and nitrogen compounds, it is even more necessary to study The rule of austenite grain growth.
Austenite grain growth law analysis Option 7 different temperature in 900 ~ 1250 ℃ range, and heat the Nb Micro-alloyed Steel for 10 minutes, then measured average austenite grain size and the level of grain.
Higher than 1150 ℃, the grain growth process grow unevenly.
When Heating temperature (Th) is low, such as Th = 900 ℃ or 930 ℃, the number of the undissolved second phase particles is larger.
The observation to several different samples precipitates in the field shows that as the temperature increased, the number of undissolved second phase particles gradually reduced, the observed proportion of fine particlesdecreased, the average particle size increases.

Table 1: Table shows the duration and number of thermal cycles time.
The cyclic thermal process also demonstrated a decrease in the volume fraction of DIM with increasing temperature and number of cycles.
Therefore, the nuclei inherit the orientation of the parent subgrains and change in austenite grain orientation occurs only after a reasonable grain growth [14].
(c) increase recrystallised fraction can be noted with increasing number of thermal cycles.
Therefore, an increase in the strain heterogeneity due to the thermal cycle could be responsible for the grain refinement of the cold deformed austenite grains.

The Vickers hardness number for the as-received Y-TZP material decreases to a very small extent after 560 thermal cycles and increases approximately 2%, after 1200 thermal cycles.
Theory of residual stress measurement and grain size evaluation.
Vickers hardness and Young’s modulus of zirconia The Vickers Hardness (HV) numbers of the Y-TZP sample were evaluated both as-received and up to 1200 thermal cycles.
Vickers hardness number for the as-received Y-TZP material decreases to a very small extent after 560 thermal cycles and increases approximately 2% after 1200 thermal cycles.
Vickers hardness number for the as-received Y-TZP material decreases to a very small extent after 560 thermal cycles and increases approximately 2%, after 1200 thermal cycles.

Greer, Grain refinement of Al alloys: Mechanisms determining as-cast grain size in directional solidification Acta Mater. 53 (2005) 4643-4653
They proposed that the final grain size, d, is linearly related to the reciprocal of growth restriction factor for a number of alloy systems, i.e.: d=a+bQ Eq.(2) They stated that a is related to the number density of active nucleating particles while b to the diffusivity of the alloying component under consideration.
Men et al have to assume grains are mono-sized.
The number of growing grains is determined by a free-growth condition.
Fig. 2a shows predicted grain size and 1/Q relations.

This means that we are particularly interested in the number of grains that nucleated and grew independently.
The third issue is whether the average grain sizes should be calculated with respect to the grain area (or grain volume) or to the grain number.
In this case the average of the grain number is the most appropriate quantity.
The area size of a grain was obtained from the number of data points in the grain multiplied by their pixel size.
Table 1: Average grain size as a function of the number of grains considering all grain boundaries with a misorientation larger than 3° (small angle and large angle grain boundaries).

The model includes: (i) a grain-boundary migration-equation driving the evolution of grain size via the mobility of grain boundaries, which is coupled with (ii) a single-internal-variable (dislocation density) constitutive model for strain hardening and dynamic recovery, and (iii) a nucleation equation governing the total number of grains by the nucleation of new grains.
For instance, grain-boundary migration plays an important role because it is one of the main phenomena controlling the final grain size.
At any time, each grain, identified by its number i, is characterized by its diameter Di and its dislocation density ρi, which is assumed to stay homogeneous within the grain.
(ii) Grain boundary migration.
(iii) Nucleation of new grains.

Grain growth controlled by particles able to move together with grain boundaries is investigated by means of numerical simulation.
Introduction Particle-controlled grain growth is usually associated with the grain boundary (GB) pinning by immobile particles [1].
Unfortunately, there was not taken into account that a moving GB sweeps out particles from the traversed volume, which increases the particle number on the GB above that corresponding to their random spatial distribution.
As nA= nV/SV (nV is the number of particles per unit volume, SV=3/D the specific boundary area in 3D microstructure [7], and D the current mean grain diameter), nA= nVD/3 = fD/(4πr3)
Particles on Grain Boundaries.