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Virtual Water theory also attracted large numbers of scholars to research in China, because virtual water can be efficient in allocation of water resources in the country.
Virtual water futures aim at solving the shortage of grain market supply and grain reserves.
They are suited to take on this role throughout the grain business.
Food companies can grow according to the different stages of grain futures to protect the food supply.
Grain futures hedging can protect the farmers’ salary, while the grain production fluctuates greatly.

The number of black dots was much because of the high oxygen content in the weld metal.
An austenite grain marked ‘A’ deserves considerable attention.
Snapshot (a) shows one austenite grain marked ‘A’.
The black dots are inclusions; the number of inclusions is less than that in the weld metal due to low oxygen content.
Snapshot (a) shows one austenite grain marked ‘A’; the grain size of austenite is about 0.7 times that in Ti-killed steel.

The phenomenon is intensified with the continuous advancement of the abrasive grain, at last the atom crystal on the front of the abrasive grain are piled up disorderly, which leads to the appearance of non-crystal layer.
With the continuous advancement of the abrasive grain, some atoms of lattice reconstituted and a part of non-crystal pill up on the front of the abrasive grain (shown in Fig.4b and c).
This kind of fluctuation will appear repeatedly while the abrasive grain advances continuously.
Therefore, crystal lattice deformation and non-crystal layer primarily centralize under the front of the abrasive grain while the distribution of deformation and non-crystal layer under the abrasive grain relatively decrease.
Journal Title and Volume Number (to be inserted by the publisher) 215 Conclusions By means of molecular dynamic simulation and from the view of micro-scale, problems such as the physical and mechanical features, the mechanism of material removing and surface generation in the microscopic zone near the action point of abrasive grain in grinding process is intensively studied.

No significant strain was observed in the former β grain boundary region.
The average β grain size, α colony width, α layer and lamellae widths, and width of the inter-lamellar β phase (β-lath) are listed in Table 1.
This area exhibits a number of interesting microstructural features like the presence of β and α layer triple joint and β grains which contain a network of α-colonies with different orientations.
From the strain map, one can also observe that the α-layer at the β-grain boundary does not exhibit any major strain localisation.
From the previous results, the lamellar orientation seems to play a role on the localisation of strain within a grain.

The equiaxic structure of the magnesium matrix grains suggest that deformation proceeds by the grain boundary sliding (GBS) mechanism.
Thus, the fine grain size of the magnesium is kept during superplastic regime, preserving the fine grain size of the alloy below a critical value at which GBS would not work.
Conclusions From the present work the following conclusions can be drawn 1) All interfaces between the phases constituting Mg-TM-(Y,RE) alloys are appropriated for the occurrence of grain boundary sliding in the temperature range 300-400°C. 2) Coarse LPSO-phase particles make harder grain boundary sliding because they cannot accommodate properly rotation of magnesium grains. 3) Addition of small amounts of rare earth elements is enough to promote grain boundary sliding of the alloys.
Cracking and homogeneous redistribution of MgRE particles acts beneficially accommodating grain rotation of magnesium grains during sliding.
Acknowledgements We would like to acknowledge financial support of the Spanish Ministry of Economy and Competitiveness (MINECO) under project number MAT2012- 34135.

The results showed that the grains were refined by adding Ca,Sr,Gd and Y.
Strip Mg24(Gd,Y)5 ,granular Mg5(Gd, Y) together with less high temperature stable Mg17Sr2 distributed around the grain boundary, they hampered the growth of magnesium grain (Fig.2).
There were a large number of defects in the as-cast microstructures of AZ91D ○ Mg ▲ Mg17Al12 ● Mg17Sr2 ★ Mg5(Gd, Y) ■ Mg24(Gd, Y)5 ○ Mg ▲ Mg17Al12 ● Mg17Sr2 Fig.2 EDAX of the AZ91D-0.4Ca-0.3Sr-3Gd-3Y alloy Fig.3 XRD of magnesium alloy a) AZ91D-0.4Ca-0.3Sr b) AZ91D-0.4Ca-0.3Sr-3Gd-3Y magnesium alloys, α-Mg grain was refined obviously by adding Ca and Sr ,which also made β-Mg17Al12 finer greatly.
The addition of Sr can decrease the volume of the eutectic structure at grain boundary of alloy.
Sr was precipitated as Al17Sr2.The distribution of Al17Sr2 might pin the grain boundaries, prevent grain-boundary from slipping and decrease shrinkage and grain boundary britdeness , thereby strengthen the alloy.

It has been repeatedly observed that grain growth and texture changes occur in Co thin films at temperatures already well below the martensitic transformation [3,5,6].
grains with a grain size of only some nm.
The emergence of an f.c.c. 002 reflection at �=60° agrees with a <111> texture of the f.c.c. grains.
In the as-deposited state, the Cu reflections are sharper and more intense as compared to the Co reflections (Fig. 3a), resulting from the larger grain size in Cu.
phase still prevails, and the small fraction of f.c.c. grains increases significantly only above 550°C.

Implementation of neural networks There exist multifarious parameters in neural network implementation, whose manipulation brings about a change in the performance, speed and accuracy of the network.[13] Number of network layers, number of neurons in each layer, network learning rate, and many other factors are among such parameters.
Ordinal numbers are used to indicate the total number of neurons in each layer.
It is noteworthy that in determining the number of the layers and the neurons, increasing the number of neurons, as the smallest processing units, does not necessarily lead to superior network speed and accuracy. [11, 13] Network learning rate is another significant parameter which needs to be considered in network implementation.
On the other hand, we know that the grain boundary with a high impurity level is susceptible to Martensite nucleating, so, as the impurity concentration in grain boundaries increases further, the more Martensite will be seen in the final structure.
Chang, The effect of ferrite grain size and martensite volume fraction on the tensile properties of dual phase steels, Acta Metal. 33-5 1985 897-903.

Instead, some grains with a mixture of Cu and Al were observed within the Al bond pad as shown in Figure 1b.
This region consists of 2 visible grains within the Al bond pad (refer Figure 1b).
Besides, this diffusion in Si was apparently not uniform in its image contrast which indicated a non-uniform elemental distribution as HAADF imaging contrast is dominated by atomic numbers of constituting atoms of the specimen [15].
This is again due to the atomic number dependence of HAADF imaging.
At the bonding temperature of 100°C, the IMC formation was inhomogeneous and dominated by grain boundary diffusion.

The investigated semi-finished products were graded by their repair ability (by the number of allowed repeated local heating of the material during repair).
Minimum values of the impact of a metal of coarse grain area of HAZ (lower envelopes) depending on the number of reheats and linear energy The data obtained show that the studied steels of K70 (X90) strength class must have appropriate limitations when applying repair technologies based on heating by an electric arc.
The obtained test data allowed the gradation of the investigated semi-finished products according to their repair ability, i.e. by the number of permissible repeated local heating of the material of parts during repair (Table 2).
When reheating, it is necessary to provide the displacement of the heating source relative to the area of coarse grain of HAZ formed from the previous heating.
Conclusion The test results of steel strength of K70 (X90) class made it possible to grade the investigated materials by their repair ability, i.e. by the number of allowed repeated local heating of the material of parts during repair.