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By a method of discriminate analysis, the content of organic matter, alkali hydrolyzadle nitrogen, rapidly available phosphate, rapidly available potassium were used as the identification factors, and soil nutrient data and grain output were analysed.
The twelve data sets of soil nutrient and grain yield data are shown in Table 1.
Table 1 The twelve data sets of soil nutrients and grain yield Numbers 1 418 0.84 76 4.5 71 2 424 0.89 63 6.2 86 3 406 0.80 58 5.7 51 4 401 0.73 53 3.1 58 5 505 0.96 70 7.4 74 6 464 0.88 79 8.5 73 7 422 0.90 60 5.7 63 8 406 0.78 58 6.6 62 9 367 1.03 61 3.7 68 10 457 0.96 52 8.2 85 11 404 1.06 60 6.8 90 12 375 0.67 66 4.5 75 Where denotes grain output (kg/666.67m2), denotes Organic matter conc. (%), denotes Alkali hydroly-Zadle N (μg/ g), denotes Rapidly available P (μg/g), denotes Rapidly available K (μg/ g).
Table 2 The evaluation criteria of soil nutrient grade Grades Criteria Corresponding to Numbers I y≤400 9,12 II 400＜y≤430 1,2,3,4,7,8,11 III 430＜y≤460 10 IV 460＜y≤490 6 V 490＜y 5 Discriminant Analysis Techniques (DAT) If individual is composed by m related factors , there has (1) After forecast object is divided into G classification, all sample size N of m related factors is divided into G groups according to the different classification and the sample size in every group is .
Table 3 The results of reporting Numbers Exact Results Forecasting Results Evaluating Results 1 2 2 √ 2 2 2 √ 3 2 2 √ 4 1 2 × 5 5 5 √ 6 4 4 √ 7 2 2 √ 8 2 2 √ 9 1 1 √ 10 3 3 √ 11 2 2 √ 12 2 1 × Now, there is a soil ground with organic matter =0.68%, alkali hydroly zadle =70μg/g , rapidly available =4.5μg/g, and rapidly available =78μg/g , the level of this soil ground is rated as shown below

The grain sizes of as-sintered specimens were 230 nm and 450 nm, respectively.
The increased deformability to failure with decreasing grain size was probably a consequence of increased grain boundary sliding in the fine-grained materials and a result of decreased local stresses; while in coarser grained materials, these stresses would enhance cavitations propagation, thereby limiting the high temperature plasticity.
During the super- plastic forming, grain boundary sliding and coordination process were generally realized to be the superplastic mechanisms in the superfine-grained ceramic.
Acknowledgements This work was supported by the National Natural Science Foundation of China under grant numbers 51175059, 50875032 and 50505005, and also supported by Program for New Century Excellent Talents in University under grant No.NCET-10-0278.
Han, The superplastic deep drawing of a fine-grained alumina?

This would bring the impurities or air pores into the grains.
Results showed that grain growth was inhibited at 850℃.
But at 875℃, densification rate increased along with grain growth, suggesting a large number of grains with lots of grain boundaries and large grain boundary energy.
As a result, abnormal grain growth occurred.
At 900℃, pores continued expelling along the grain boundaries and the density continues increased whereas grain size decreased due to carbides precipitation which inhibited grain growth.

This inhomogeneity can be connected with [1-3]: • volume fraction, shape, size and arrangement of phases or particles, • grain size in polycrystalline materials.
The density of the nuclei can change linearly, exponentialy, according to the power function, according to the band-type function or arbitrary (for each layer the number of nuclei is introduced by the operator).
The generating procedure is divided into three stages: nuclei generation, nuclei growth and smoothing of generated grains [6, 7].
All above methods require some characteristic point connected with each particle (or grain), called reference point.
As the reference points for particle systems as well as grains in polycrystalline models the centers of gravity have been assumed.

Therefore, recrystallized grains will appear as bright regions, while deformed structures will showup as dark regions.
The figure shows distinctive recrystallized grains, and the microtexture consists primarily of <100>+<111> components, with a high density of <100> grains.
Higher temperature annealing resulted into a secondary recrystallization, i.e. abnormal grain growth, with a corresponding change in texture from a <100> dominated recrystallization texture to a <111> dominated grain growth texture.
While Outer surface Mid region surface Inner core the inner core and mid section developed very large grains (~300µm), the outer surface had relatively very small grains (~20µm).
Acknowledgement The financial support given by the National Science Foundation (NSF) through the PREM program, grant number DMR 0351770 is gratefully acknowledged.

In a boundary region of coating processes of crushing of grains and particles of the second phase is visible, see Fig. 1.
CSR – is a part of the grain, separated from the next part by a defective wall – high-angle grain border or low-angle dislocation wall.
A lot of reflections appeared along the circles indicating high-angle disorientation of next grains.
The number of tyazhs decreased in the electron diffraction pictures, and, therefore, share of high-angle disorientation has increased.
Krylov, G.V.Tsvetkova, Features of plastic deformation and wear of the abrasive grains during high-speed machining, J.

A number of further tests were carried out where a smaller strain was followed by an anneal for various lengths of time.
Following all single hit tests, a significant amount of dynamically recrystallised grains were observed in necklace structures around the grain boundaries.
Further analysis of the regions surrounding the recrystallised grains has shown features such as a high level of lattice rotation near to the grain boundaries and a considerable number of subgrains bordering, and of the same dimensions as, the recrystallised grains.
The fully recrystallised material, obtained by a long post-deformation hold at high temperature showed an almost entirely random texture and grain sizes that were approximately half that of the starting material.
There was also strong evidence that the initial dynamically recrystallised grains underwent grain growth, which is thought to be the main mechanism of static recrystallisation in Elektron™ 675 under these temperature and time conditions.

The results show that the grains and bulk density increased with the increasing of sintering temperature and sintering times.
The average of grain size was measured by using line intercepts method according to ASTM E 112-96.
Besides that, the porosity also decreases due to increasing numbers of contact and the contact area between spherical particles.
They have reported that at high temperatures, densification becomes active, further adding to compact strength by pores elimination and increasing the particle coordination number (number of bond per particle).
Therefore, the grain growths and pore structures are affected by the sintering temperature and sintering time.

In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve both full density and grain refinement of metallic powders with least grain growth, which is considered as a bottle neck of the bottom-up method that uses the conventional powder metallurgy of compaction and sintering.
The main advantage of SPD processed materials, compared to other nanostructured materials processed by gas condensation or ball milling with subsequent consolidation, is that it is possible to overcome a number of difficulties associated with residual defects and powder contaminations in the compacted samples.
Indeed, grain growth, which was considered as a bottle neck of the bottom-up method that use the conventional powder metallurgy of compaction and sintering.
In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve both full density and grain refinement of metallic powders with least grain growth.
Figure 4 shows low magnification scanning electron micrographs of longitudinal sections of 200 ℃ equal channel angular pressed Al-20 wt% Si bars after various number of route C passes.

The RE compound precipitations presented not only as small spot particles inside the α-Mg grains but also as line shapes in grain boundaries.
Increasing MM content in Mg-2%Zn alloy, the amount of second phase precipitation increased both inside grains and grain boundaries, in addition, the precipitation particle sizes inside a-Mg grains become small and those in the grain boundaries become more and more continuous and form network gradually at high MM content.
From fig.4 it can be found that there are a large number of twins occurring both inside α-Mg grains and grain boundaries as well.
As MM concentration is no more than 0.6% the twins most present inside α-Mg grains, and the quantity of twin and the α-Mg grains presenting twins increase when increasing MM addition.
However, as MM concentration reaches 1.0% or 1.5%, the twins tend to present near grain boundaries or sub-grains and form stripped bands along the extrusion direction.