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Recent experiments showed that the XRD patterns of the nanostructured materials produced by SPD are characterized by a number of specific features in comparison with the patterns of corresponding coarse-grained materials [3-5].
A concurrent effect of a whole number of structural factors (small grain size, large nonuniform distortions of crystal lattice) on X-ray diffraction in SPD nanomaterials results in considerable difficulties in the interpretation of XRD patterns and, correspondingly, in the determination of the structure parameters of these nanomaterials by the XRD method.
When specifying the EGBDs density value in the nanostructured material we assumed that each crystallite contains a certain number of the dislocations (N) with Burgers vector b at its faces, so that these parameters correspond to the specified linear EGBDs density 
 at a given grain size d; i.e.
The grain size was about 170 nm.
However, the grain growth was not observed.

The addition of Al–5Ti–1B master alloy to the aluminium melt introduces a large number of heterogeneous nucleating sites such as TiAl3, TiB2, and (Al,Ti)B2 particles into the melt for grain refinement [6–10].
Fig. 3 (a-c) depicts the effect of annealed grain refiner on the grain size of the cast Al-7Si-3Cu alloy.
It is observed that the annealed grain refiner produced more fine and equiaxed grains than as received grain refiner.
This is attributed to the fact that the number of TiAl3 particles increased.
This is due to the larger number of TiAl3 phase in annealed alloy.

According to the architecture characteristics of the grain storage system and the main factors influencing the safety of the grain storage, this paper has proposed a two layers data fusion system based on multi-sensors grain storage monitoring technique, which is used to identify the safety of the storage.
During the grain storage procedure, the factors influencing the grain most are temperature, moisture, insect pests and micro-organism, these factors correlate and interact with each other, causing influencing elements such as moisture condensation, stack fever, stack mildew and insects, which result in grain store stability and safety varying, grain storage quality descends.
In this way, make judgment to current grain state according to the recognition frame.
Summaries and Prospect This paper has collected data relevant to the grain storage safety based on current grain information monitoring system.
The proposed method could effectively evaluate grain storage safety state of a certain time, thus judge out grain storage state quality.

Since grain subdivision occurs by movement and accumulation of dislocations, grain refinement by plastic deformation should proceed more efficiently in systems, e.g. fcc metals, with a larger number of active slip systems (or slip systems that can become active).
This result indicates that grain refinement by plastic deformation proceeds more efficiently in systems with a larger number of active slip systems.
The numbers indicate hardness values in GPa, gray color indicates results from the literature.
Numbers indicate the RCR repetitions.
However, this peak did not sharpen after a large number of passes.

The results indicated that the specimens with fine grains (30µm) own the longest fatigue lives than those with intermediate (80µm) and coarse grains (210µm).
The fatigue stress amplitudes of the specimens increased with the grain refinement, although the fatigue lives of the specimens with intermediate and coarse grains were close.
Effect of grain size on fatigue life Three different grain sizes of 316LN stainless steel are obtained by solution treatment at different time and different temperature.
Effect of grain size on the slip bands and crack initiation.
From Fig. 5, it is easy to find that the larger the grain size, the more the number of crack initiation and persistent slip band, under the same strain amplitude.

It is found that the initial coarse grains of Ti-50.9at%Ni alloy were refined into submicron grains, smaller than 0.5 um in size, after eight passes ECAE at 500ºC.
Martensitic transformation temperatures decreased remarkably after one pass ECAE and more gently with increasing the pass number of ECAE.
Many long blocks were divided into fine equiaxed grains or subgrains(Fig.1(c)).
After four passes ECAE, no grains or grain boundaries can be identified under optical microscope.
Martensitic transformation temperatures decreased remarkably after one pass ECAE and more gently with increasing the pass number of ECAE.

In this reference, SE-Cu 58 (99.95% copper) with fine grains showed a higher flow stress for 25 and 500μm foil than coarse grains.
A number of references considered the effects of nose radius against punch diameter for 0.5mm thick AZ31-O [20] and Al-O [21].
The number of layers of material ARB2c, ARB3c, and ARB4c were 18, 36 and 72 layers, respectively.
The grain size d obtained by EBSD method are shown in Fig. 5 and 6.
Approximately 93% grain refinement has occurred after the first ARB cycle ARB1c, and about 0.6% change in grain size between the first and fourth ARB cycle.

Manufacturing and Experimental Research of Fine Grain Diamond Grinding Wheel Based on Magnetic Field Controlling S.H.
The manufacturing and dressing of fine grain diamond grinding wheel based on magnetic field controlling (acronym FGDWMC) were introduced.
Fig.5 is the SEM photo of the surface of plain wheel，from which the grains aggregation can be seen.
Table 1 Grinding Conditions Grinding Types Grain Size Grinding Wheel Dia.
Acknowledge This research is sponsored by the NSFC (Grant No. 50975084) and the National Key Technology Program (Project number 2010ZX04001-151).

Figure.1 Correlation between a marine oxygen isotope δO18 reference curve (numbers signify stages) with Zhuli section, 1-cultivation intervals, 2- loess intervals, 3- paleosol intervals.
Grain-size analysis All the samples show a bimodal grain size distribution (Fig.2a), with higher mode at 79-89μm and lower mode at 10μm and the valley at about 20μm.
(b) Grain-size classes vs. standard deviation of Zhuli section Figure.4.
Records of magnetic susceptibility and grain size in Zhuli section.
(2) All the samples show a bimodal grain size distribution, and grain-size curves indicate that environment-sensitive size fractions of this section are 39.81-44.67μm and 79.43-89.12μm respectively, by analyzing grain-size class vs. standard deviation values method

Larger effective strain gradients generated with compression pressure of 62 MPa and rotation number of 30 revolutions at the radius of 4 mm.
With the increase number of rotation, the effective strain is larger.
All of forming conditions, the effective strain distribution is obvious when number of rotation is 30 revolutions.
The effective strain increases when the number of rotation increase and strain gradient is more obvious.
In Fig.10, when the number of rotation increased to 30 revolutions, the grain size distribution of the contact plane will approach the value of 5 μm, but the simulated effective strain will continue to increase.