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It was found that if the volume and property of the paste that remains after filling the space in between the aggregates in compacted state is kept constant, the consistency of a mixture can be characterized by the number of aggregates corresponding to each grain size regarding the sieve analysis test.
The size distributions of grains in the second group are composed regarding the NEN 2560.
The dominant particle size zone is defined as area in which the number of grains is considerably higher than the other grain sizes (Fig. 6).
This chart can be obtained from the number of grains which remain on each sieve during the sieve analysis.
Conclusions The results show that grading of the aggregates regarding their remaining mass on each sieve is not enough for representation of a highly poly disperse granular skeleton and that grading regarding the number of grains remaining on each sieve is also necessary.

For example, the interfacial energy of Σ = 3 twin grain boundaries in copper changes with changing inclination of the grain boundary plane from the {111} symmetrical tilt grain boundary.
Solid lines represent non-coincidence grain boundaries (Σ ≥ 51), dashed lines are the Σ = 3 twin grain boundaries.
Nevertheless, the remaining networks of the original non-coincidence grain boundaries are still partially preserved but the number of the twin grain boundaries is substantially increased due to low stacking fault energy in silver. 5500 µµµµµµµµmm It is apparent from Fig. 2 that there is an extended intergranular failure of the object.
In Fig. 4, the non-coincidence (Σ → ∞) grain boundaries terminate exclusively at the Σ = 3 special grain boundaries.
These grain non-coincidence grain boundaries are heavily corroded.

We then multiplied the mean number of pollen grains per anther by the number of stamens per flower to estimate the number of pollen grains per flower.
The P/O ratio was finally calculated as the number of pollen grains in one anther divided by the number of ovules.
The number of pollen grains that changed to red color per 100 pollen grains was taken as the pollen viability index [1].
The pollen grain numbers, ovule numbers, and P/O ratios for this species are given in Table 1.
The pollen grain number, ovule number, and P/O ratios for Robinia pseudoacacia Stamens no.

Thus, for a large initial grain size, grain refinement can be achieved at low values of Z.
To solve this problem, Derby proposed [10-11] the following correction for a large number of materials: 10 1 3/2 <            < b D µ σ (3) Sakui et al. [12] and Sakai et al. [13] demonstrated that the critical condition for the transition from single peak to multiple peak curves corresponds microstructurally to D0 = 2 Dss.
When the initial grain size D0 is smaller than Dss, multiple peak dynamic recrystallization is predicted, which leads to grain growth; while for initial grain sizes larger than Dss, a grain refinement associated with a single peak dynamic recrystallization is predicted.
This can be explained because a fine grain size provides a great number of nucleation sites, which in turn favours dynamic recrystallization.
This grain size can be related to the initial grain size, as in the literature there is mention of a transition between grain growth and grain refinement once the initial grain size is equal to twice the size of the steady-state.

The grain size level numbers (G) of alloys containing varied RE contents are shown in Table 1.
The grain size level numbers increase with the increase of the RE content.
The grain degree stage number was determined by area method.
The formula of G is shown as following [8]: 3. 2 ALogN G Log = − (1) Where G is the grain size level number, NA is the number of grains in per square millimeter.
RE content (wt%) 0.0 0.2 0.4 0.6 0.8 1.0 Grain size level number 0.19 0.30 0.47 0.51 0.77 1.09 Fig. 1 Microstructure of the as-cast alloys in low magnification case (a) Mg-16Li-5Al (b) Mg-16Li-5Al-0.2RE (c) Mg-16Li-5Al-0.6RE (d) Mg-16Li-5Al-1.0RE (b) 100w� (a) 100w� Table 1 Grain size level numbers (G) of alloys 100w� (d) (c) 100w� Fig. 2 shows the microstructure of alloys at higher magnification.

Grain number across thin sheet metal thickness direction is another important factor that affects flow stress.
The main feature is a modification of mechanical properties (like Hall-Petch coefficients and flow stress) when grain number across thickness is lower than an critical value [4,5].
In case of high purity nickel, the two critical grain numbers are 1 and 4.
In order to determine the critical grain number Nc, Q.
Conclusions Factors that affect mechanical properties of thin sheet metal in micro plastic forming processes were analyzed and summarized: thickness, grain size, grain number across thickness and surface properties.

Thus, the most two important parameters in the HPT process are the number of revolutions, and the imposed pressure.
Increasing the number of revolutions up to 4-revolutions revealed further refinement of the grains, subgrains, and substructure sizes to 30, 1.9 µm, and 250 nm (in Fig. 1b).
Due to the SPD induced with increasing number of revolutions up to 4 revolutions under a pressure of 3 GPa, the consolidated equiaxed powders subgrains were elongated but rather in different directions following the orientation of slip planes for the non-directional grains.
Because of the intense deformation per revolution, it was suggested that enormous numbers of dislocations were generated so that the subgrain boundaries further evolve into grain boundaries with large angles of misorientation which is usually assisted with dynamic recovery [13].
HPT processing was conducted under different conditions of pressures and numbers of revolutions.

The size of the grains is controlled by a packing limit in order to obtain realistic mass transfer values during the grain-to-grain interaction in the control volume.
The number of grid cells has been increased from 180 to 4300 in half of the symmetrical domain.
The grains sink down and settle at the bottom region.
The number of grid cells has been increased from 180 to 4300 to define an optimal grid size, to prove the reliability of model implementation.
The results show that the macrosegregation pattern does not change significantly above a well-chosen number of grid cells, at least from 2780 cells in our case.

In this paper, we accordingly analyze the REV for different porous media with different grain sizes based on computed tomography (CT) measurement.
Our results show that that CT measurement is a relible method for REV analysis and that there is an appropriate linear relationship between grain size and REV.
REV of glass-bead packs with different grain sizes The grain sizes of glass beads are shown in Table 1.
(2) There is an appropriate linear relationship between the grain size and REV.
Glover and Nicholas Déry :Streaming potential coupling coefficient of quartz glass bead packs:Dependence on grain diameter, pore size, and pore throat radius.

.:81-424-75-0650 e-mail: wmfjindo@din.or.jp Atomistic Simulation Study of Dislocations and Grain Boundaries in Nanoscale Semiconductors K.
In terms of X and r the particle number Ne and energy functional W are given as Ne = tr[3X SX - 2 X SX SX )S], ( ) [ ]HXSXSXXSXtr 23 =W
The major difference in the grain boundary properties between the nanoscale and bulk crystals is in the significantly smaller excess energy of the grain boundary in the former nanoscale crystals.
In Fig.3c, one can see no gap states appear for S=9(221) tilt grain boundary in Si-nanowires.
This is due to the fact that the effects of compressed and stretched bonds in the core region of the grain boundary almost cancel and effective coordination number remains around the value of 4.