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The Damping Effect in the Propagation of the Cracks in Fine-Grained Carbonate Concrete V.V.
At the same time, from a significant number of well-known filler additives, a group of mineral additives can be distinguished with some feature to turn small crack inducing solid areas in the concrete stone into plastic zones displaying damping effect of depriving crucial crack the energy to further growth to full failure of the specimen [5].
From the above brief overview, it follows that a number of researches, design development and production experiences in the application of the additives causing mechanism of damping in the propagation of the cracks products has been accumulated.
Limestone grains ranging in size from 5 to 0.05 mm were used as a filler in fine-grained carbonate concrete.
Modifying of fine-grained concrete by micro and nanodimensional particles of a shungit and dioxide of the titan.

As mentioned above, subgrains were frequently found inside some larger grains.
Micrographs of a larger grain and a subgrain boundary within the larger grain in the HPT Al-0.5Mg alloy: (a) TEM bright-field image of the larger grain; (b) HRTEM [110] image taken from the right frame in (a), showing the sub-boundary formed within the large grain and a SF appearing nearby the boundary; (c) inverse Fourier image from the frame in (b), showing 60° perfect dislocations at a sub-boundary.
A large number of excess dislocations for slip trapped at non-equilibrium GBs (Fig. 3c), as well as dislocations stored near the grain boundaries (Fig. 4), can facilitate grains to slide or rotate at room temperature, and therefore increase the ductility [27].
In the ultrafine-grained (UFG) regime, i.e. grain size in the 100−1000 nm range, the traditional dislocation mechanisms may still remain dominant in controlling plastic deformation.
In the lower nanometer regime having a grain size below 10 nm, deformation processes could be controlled by the grain boundaries, e.g. such as grain rotations and grain boundary sliding.

The strong elastic stress accumulated by shearing texture is responsible for oriental growing of a great number of grains during recrystallization.
A number of unusual properties have been reported in ultrafine grain materials produced by severe plastic deformation (SPD).
AARB effects on grain refinement.
From fig.3(a) and (b),we can see that gains were squashed and there were subgrains which have low angle grain boundaries appear.This was because that friction of inner grains and grains was intensified,and grains in the place of grain boundaries occurs slide,and crystal plane in part grains occurs glide when rolled pieces pass crossover area,meanwhile,because of the effect of AARB,2/3 large grains transform numerous subgrains which have low angle grain boundary ,i.e.2/3 large grains were broken into numerous small subgrains whose size are about 5um;from fig.
The strong elastic stress accumulated by shearing texture is responsible for orientable growing of a great number of grains during recrystallization.

Fundamental Property of Metals - Grain Boundaries Phase Transition as a Basis of Nanostructured Layers, Materials and Composites Production Y.A.MINAEV Leninsky prt.4, Moscow 119049, Russia ymin36@mail.ru Keywords: Grain boundaries phase transition, nitrided coatings, hard metals and steel alloys Abstract.
Introduction For a development of coating technology we focus on the defects on a grain boundaries and description of grain boundaries phase transition (GBPhT) phenomena.
The valuation for a number of metals gives downturn in melting temperature of a surface layer on hundreds of degrees.
On EM micrographs at large magnification it is possible to see inside large carbide grain those fine, which misoriented with matrix "general" grain.
Fine grain has more dark contrast (Fig.3a).

The microstructure of 0°specimen are of equiaxed grain due to dynamic recrystallization after compression, while the grain shape of 45°and 90°specimens are still of lamellar grain structure.
Therefore, the dislocations concentrated near the grain boundary.
The propagation of dislocations to the matrix is easiest when the maximum shear stress in grain is parallel to longitudinal grain boundaries by applying the external stress in the 45° direction of elongated grain structure.
This could be attributed to the lamellar grain structures and the texture of the extruded bar. 2 The microstructure of 0°specimen are of equiaxed grain due to dynamic recrystallization after compression, while the grain shape of 45°and 90°specimens are still of lamellar grain structure.
Acknowledgements It is a project supported by natural science foundation of shanxi province China (project number: 2009011028-1; 2011011021-1).

Positron lifetime calculations using the PAW method are highly sensitive to the number of valence electrons in the PAW dataset.
Depending on the cluster size, the number of atoms removed from the cell ranged from n = 1 to n = 40.
Coincidence-site lattice grain boundary Among the enormous number and complexity of grain boundaries, there is a special type known as coincidence-site lattice (CSL) grain boundaries, where several atomic sites from one grain align precisely with those in the neighboring grain.
Compared to random grain boundaries, CSL grain boundaries are thought to have lower energy due to their better atomic alignment, making them an important subject of study in grain boundary science and engineering [29].
In reality, there are an infinite number of possible lattice variants for grain boundaries.

This confirms that large grains are already recrystallized after ECAE. 0 5000 10000 15000 20000 30 50 70 90 110 130 Image quality Number ECAE 30s 7min30s Fig. 5 : Number of indexed points versus image quality.
Inspection of grain size distributions shows that, after 30s annealing, the number of the smallest grains (<0.5 µm) has slightly increased whereas the number of large grains (>1.5 µm) has remained constant (Fig. 6a).
Indeed, the average size of dynamically recrystallized grains (IQ>70) remains constant and equals 1.4 µm after 30s annealing. 0 100 200 300 4000.1 1 10 Grain size (diameter) (µm) Number ECAE 30s 7min30s (a) (b) Fig. 6 : a) Evolution of grain size during copper annealing at 473 K, b) Distribution of image quality of small grains (<0.5µm) after 30s annealing.
After 7min30s annealing, the number of large grains increases at the expense of the small ones.
As already suggested by the EBSD analysis and the hardness curve, this result confirms that, after 30s annealing, the copper is still recovering and the number of new oriented recrystallized grains, is not sufficient to change the texture.

Temperature and humidity are main factor in grain analysis of ecological storages.
Through observation on temperature and humidity of each part of grain heaps, variation laws of internal environments and features of grain heap environments are reflected.
This network relies on the complexity of the system, by adjusting the connection between the numbers of nodes within the relationship so as to achieve the purpose of information processing.
Artificial neural network is an adaptive information processing system composed of a large number of simple processing units connected in parallel non-linear.
A grain depot environmental data is in table 1 below.

Such materials possess an inhomogeneous microstructure especially after a small number of ECAP passes which makes it necessary to use a high-resolution 3D method for microstructure characterization.
All voxels that form one grain have a misorientation below 5°.
The optimal number of voxels for defining a grain is selected ten.
Misalignment of the sections can cause small grains, which do not actually exist, to be included when less than ten voxels are considered while more than ten voxels would cause small grains which are typical for ultra fine grained material to be excluded.
The true grain volume was calculated by Vgrain=Nv.Vvoxel (2) where Nv is the number of voxels and Vvoxel is the Volume of voxel.

Grain yield has been reported that significant correlation with grains per plant [6], number of filled grains per panicle, number of productive tillers per square meter and 1000 grain weight [7].
Data were collected: number of tillers plant-1, plant height, number of panicle, panicle length, number of seeds, seed length, seed width, 100 grain weight and grain yield.
Rice 102 Rice 231 and Rice 199 were the most of number of grains per panicle as 171.00, 163.33 and 159.37 grain per panicle respectively, and Rice 263 was the lowest in number grain (57.33 grain per panicle).
Both size of the grain and number of grains per panicle decide the panicle weight.
The number of grains/panicle is a critical that determines the grain yield.