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The effect of grain composition, replacement ratios and chemical activator of recycled aggregate on compressive strength of concrete small hollow block was studied.
Results and Discussions The effect of grain composition of recycled aggregate on compressive strength.
Table 3 The effect of grain composition of recycled aggregate on compressive strength of samples No.
The main reason for this trend was that on one hand, there were a large number of microcracks in the surface and interior of recycled aggregate.
In addition, there were a large number of microcracks in recycled aggregate.

Diffusion Mechanisms in Grain Boundaries A.
Under such conditions, the number of point defects in the simulation block is not conserved and the use of Eqs. (1) and (2) is not justified.
Hence, the total number of atoms in the GB core is conserved and it can only contain an equal number of vacancies and interstitials.
Filled symbols mark the upper grain, open symbols the lower grain.
In Cu GBs studied here, the number of nearest neighbors can be as small as � or as large as � � .

It can be seen the grain size of 1#, 2#, 3# are relatively small.
At the same time, Ti-Zr combined deoxidation process used in the production could form a large number of Ti-Zr composite fine particles which could pin austenite grain boundaries in the welding process to inhibit austenite growth, and to promote acicular ferrite nucleation during cooling [6].
Fig. 7 Three-dimensional reconstruction of acicular ferrite grains and a part of a big austenite grain, showing the partitioning of an austenite grain by acicular ferrite laths or plates [8] Effect of preheating on the toughness of CGHAZ.
The fine-grained mixed microstructure has very good impact toughness.
Wu, Effect of acicular ferrite formation on grain refinement in the coarse-grained region of heat-affected zone, Materials Characterization, no. 61, pp. 726-31, 2012

The tetragonal grain size decreases with increased amounts of alumina.
Usually, the cell parameters start to increase with a grain size below 30 nm [22,23].
Initial calculation of the attractive potential for a one dimension ion arrangement, as a final segment, shows that there is a sharp decrease in the attractive potential, when the number of pairs is below 100 (See Fig. 8). 0.50 0.55 0.60 0.65 0.70 1 10 100 1000 10000 2N (N is number of pairs) Factor Fig. 8: Half of Madelung constant as a function of number of cation/anion pairs for a line of alternating cations and ions.
For an infinite number of pairs this number is ln2.
The gradual transitions versus grain size can be attributed to non-uniform grain size.

The film width can be quantified and its relationship with atomic GB structure can be clarified by studying the thermodynamic properties of premelted GB because the order parameter of PFC is the periodic local number density of atoms.
Mishin, Atomic mechanisms of grain boundary diffusion: Low versus high temperatures, J.
Gleiter, Amorphous structure of grain boundaries and grain junctions in nanocrystalline silicon by molecular-dynamics simulation, Acta Mater 45(1997) 987-98
Cannon, Grain boundary transitions in binary alloys, Phys Rev Lett 97(2006) 075502
Plapp, Phase-field crystal study of grain-boundary premelting, Phys Rev B 78(2008) 184110.

But this method owns a limitation in simulation of high Reynolds number, which is [2], when LB method is used to derive Navier-Stokes equation, one of errors is O (M2), where M is the Mach number.
It permits a reduction in error in exchange for a smaller Mach number which leads to a smaller Reynolds number, but in the engineering application of hydro turbine, turbulent exists in most of the practical flow phenomenon and high Reynolds number is often encountered.
Simulations of high Reynolds number fluid flow based on entropic Boltzmann method.
Stabilization of the Lattice Boltzmann Method Using the Ehrenfests’Coarse-Graining Idea.
Research on Lattice Boltzmann Method with High Renolds Number. 2008, 56-58

Since it included large number of high-misorientation grain boundaries, the foil was miserably brittle with no sign of plastic deformation in the tensile test [15].
However, after the grain growth at 1273K/0.5h, most of grains had {110} textures (green-colored) with few high-misorientation grain boundaries.
Other types of grains exist but are minor.
Note that among these minor grains only the grains with the cold-rolled texture are surrounded by the special, high-mobility grain boundary in the 40˚{TTP}730 <111> rotated recrystallization texture.
Then, in the next stage, i.e. in the grain growth, only the grains with the cold-rolled texture have the advantage of growing faster over the other grains, yielding the texture returning to the original, cold-rolled texture.

A large number of slip bands can be clearly observed.
The data on αexp of each grain are classified into four groups based on the number of active slip planes: grains with one slip plane, double slip planes, triple slip planes, and no slip bands.
The numbers parenthesized indicate the quantity of each type of cracks.
However as the fatigue loading proceeds, TC cracks grow so dominantly that a large number of them are even found cutting through grain boundaries.
On the other hand, in Fig. 7(a), (d) the values of h and SB show at sharp increase at some cycle numbers corresponding to crack initiation.

For the coil inner part, the strengthening effects were made of fine-grained strengthening and M/A islands strengthening.
The number of M/A island in outer part is less than that in inner part, but much than that in middle part.
The blocky ferrite number in middle part increases significantly and grain sizes become larger.
The microstructure is finer, fine-grained strengthening effect is more obvious [1].
Subgrain size is smaller and the number is more, its strengthening effect is more apparent [1].

Meanwhile its grain was refined.
The additive ZrO2 made the grain shape of Al2O3 change and the grain size of Al2O3 decrease greatly.
The bigger ZrO2 grains are dispersed on the adjacent of several Al2O3 grains, meanwhile there are plenty of thinner nano ZrO2 grains dispersed in the Al2O3 grains to form the typical intragranular and intergranular structure.
The ZrO2 grains are mainly dispersed on the edge of several Al2O3 grains, and only few white ZrO2 grains are dispersed in the Al2O3 grains.
Most Al2O3 particles are platelet crystalline of hexagonal structure in the area where large number of particles of ZrO2 disperse, while the grains of Al2O3 are big and equiaxial in the area where a few number of ZrO2 particles disperse.