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Lentil Grain Drying Application.
The values of the parameters hm, kl and kv were obtained by agreement between numerical and experimental data of average moisture content, using the least square error technique, as follows: , (11a-b) where ERMQ is the least square error, is the variance, n is the number of experimental points and is the number of estimated parameters [13].
Figure 2 - Comparison between predicted and experimental [17] mean moisture content of the lentil grain as a function of drying time Figure 3 - Predicted mean temperature of the lentil grain as a function of drying time Fig. 3 illustrates the heating kinetic of lentil grain as a function of the drying time.
Figure 4 - Liquid flux at the surface of lentil grain.
Figure 5 - Vapor flux at the surface of lentil grain.

In order to deform the material to a large total strain, the billet is pressed through the die a number of times, since its cross sectional area remains unchanged during ECAE.
Second, the initial grain size was smaller (200 µm) and the authors did not report the presence of recovered grains in the starting condition.
TD ED 0 10 20 30 40 50 60 70 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 Number fraction Misorientation angle (deg) as-deformed 400°C for 15 min Fig. 5.
Fine equiaxed grains coexist with coarser areas where grain fragmentation is less pronounced.
The mean grain size in the deformed state is 650 nm.

Grain coarsening occurs at the deformation temperature close to γ′solution temperature, and the grain grows up obviously with decreasing strain rate.
Comparing of PM process, Spray forming can keep the advantage of rapid solidificationmicrostructure characterization with fine grain size, more uniformly distributed precipitates in the matrix, eliminating macrosegregation and reducing microsegregation of alloying elements[6, 7],in addition, lower the cost of products by reducing the number of process steps.Hot deformation is important for spray formed superalloy to improve the properties.
Some pores distributes were observed on the trip-grain boundary( Fig 1a).
Increasing temperature to 1100℃, fine dynamic recrystallization grains appear around large grains, revealing necklace microstructure (Fig.3b).
When the alloy deforms at high strain rate and temperature lower than γ′ solution temperature, γ′phase and carbides in the matrix will restrain the growth of the dynamic recrystallization grain, avoiding grain coarsening[8]. most of γ′phase will solute into the matrixwhen hot deformed close to γ′ solution temperature, the increasing of grain boundary migration during dynamic recrystallization process favors the growth of grains resulted in the grain coarsening[9].

It can be seen that alumina grain grows up obviously, but its aspect ratio changes a little and the grain shape remains equiaxed.
Under restriction of the matrix alumina grains the intragranular zirconia particles within Al2O3 grains did not coarsen and still dispersed well (Fig. 4b).
With the sliding and rotation of matrix grains, some separated intergranular zirconia grains have chance to approach each other and grow up (indicated in Fig. 4b by small triangles).
Therefore, this fraction of intergranualr zirconia grains retarded the growth of the matrix grains, effectively.
Acknowledgements This work was supported by the National Natural Science Foundation of China under grant number 50375037.

To further quantify this, the prior austenite grain size of the quenched and tempered samples was analyzed using picric acid etching at 60°C within a 2 mm² area; the average grain size is presented in Figure 5.
Austenite grain size of the samples NM450 and LG960QT wit and without presence of tantalum.
This reduction is attributed to an increased number of interfaces, such as grain boundaries, which hinder dislocation movement.
This finding aligns perfectly with the microstructural refinement observed, where tantalum led to finer grains.
The improved impact resistance is expected in materials with finer microstructures because the increased number of grain boundaries acts as a barrier, effectively hindering crack propagation and enhancing the material's ability to withstand impact.

The effects of grain-refined by Pr on the morphology and the grain size of the primary α-Al in semisolid A356 alloy are researched.
Semisolid A356 alloy grain-refined by Al-La master alloy is prepared by low superheat pouring, and the size and morphology of the primary grain in semisolid A356 alloy are markedly improved by La[9].
Most grains are rosette-like or particle-like, and there are few grains with dendritic-like microstructure.
The grain size of the primary phase is coarer without Pr, about 110μm.
There are strip-like or needle-like bright areas at grain boundaries, which should be the enriching area of Pr theoretically, because the atomic number of Pr is the largest among the elements (such as Al, Si, Mg, Pr) contained in the alloy used in this test.

The potential application range of coarse-grained commercial purity titanium is limited by its low mechanical properties.
A reduction of the grain size of titanium leads to a significant increase in its strength and hardness.
This paper is concerned with application of hydrostatic extrusion (HE) for fabrication nano-grained titanium.
Nano-grained Ti processed by hydrostatic extrusion (HE), reveals considerable increase in yield stress and tensile strength, when compared with those in the coarse-grain state.
Grain refinement of the titanium microstructure achieved by hydrostatic extrusion Process Initial grain size d2 [µm] Final grain size d2 [nm] Grain refinement Initial / Final Ø50mm → Ø3mm 15 65 230 Ø33mm → Ø5mm 20 55 365 Ø20mm → Ø3mm 160 60 2670 Ø12mm → Ø3mm 10 not fully - Fig 1.Structure of Ø50 Ti - initial state Fig 2.

By a qualitative analysis of the figures, one can observe a material with a large number of pores, besides the coexistence of open and closed pores.
This large number of pores is due to the processing and is responsible for the low mechanical resistance of the compound, making it very fragile.
For the sample MB#2 it can be observed that the annealing propitiated a significant increase in the number of pores, along with an apparent growth of the grains.
The Rietveld analyses showed that the MB#1 sample possesses 89.3% of MgB2 and 10.7 of MgO phases, while for the MB#2 sample the numbers were 88.6% of MgB2 and 11.4% of MgO phases.
The authors cite traces of another relaxation process located in high temperatures, probably due to the grain-boundaries motion, but it was not possible to observe it owing to experimental limitations.

The standard does not define the number of compaction layers.
It is recommended adjusting the number of layers depending on the consistency of the concrete and the height of the mold to achieve proper compaction.
The grain size distribution curve is shown in the Figure 1.
Fig. 1 Grain size distribution curve Ordinary Portland cement CEM I 42.5 R was used in the concrete mixes.
Acknowledgements This paper was prepared thanks to the financial support of Testing methods and application of cement composites, project number SGS20/109/OHK1/2T/11 and Durability of concrete structure and assessment of its life cycle, project number SGS19/149/OHK1/3T/11.

Grain modifiers influence on the amount of nucleating particles.
This master alloys contains a large number of boride particles, which have effectively nucleated a grate number of aluminum crystals.
This effect have influence on the grain size.
This has been well demonstrated in a number of the aluminum alloys with Ti and B modifier.
The number and size of silicon particles in Al-Si alloys can by controlled by the same way like the size of the dendrite and size of the grain.