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The aggregation at the level of traffic zones aims that the number of land use functions within an area to be as low as possible.
This way, the territory of analysis is reduced to a number of traffic zones, denoted "n".
Interpretation of the results can be performed in the form of a quadratic matrix, n x n, called origin - destination matrix – ODSx, as the one presented in Table 1, in which Sx is the number of survey point.
) represent 32% and grain (T2) 25% of the total goods transported (Fig. 2), which is why further, in this case study will refer to these two main categories of goods.
The annual variation of grain and petroleum products amounts transferred in the port of Constanta (2005 to 2013).

Grain nucleation requires a minimum amount of undercooling.
The addition of inoculant lead to the formation of a large number sites for heterogeneous nucleation.
Table 2 shows the average grain sizes of A356 with the addition of grain refiner.
The grain sizes become smaller and finer with higher amount of Al-5Ti-1B.
Semi-solid process with addition of inoculant produced globular structure of α-Al grain with fine grain size.

This is due to the removal of the more heated metal into the burr and the entry into contact of metal layers with a lower temperature, where there was no intensive grain growth.
Let us trace the formation of the strength of grain boundaries along the contact zone based on the results of mechanical tensile tests (Table 4).
It is also known that when welding homogeneous metals, the process ends with joint volumetric recrystallization, leading to the formation of common grains along the contact line.
However, due to the geometric inhomogeneities of the surfaces to be joined, as well as a number of other factors associated with the chemical composition of the materials to be welded and the welding parameters, the volumetric interaction with the formation of common grains occurs not over the entire contact area, but only in some areas, as, for example, in [12].
The greatest strength in the contact zone of steels is observed in samples with the greatest number of common grains along the contact line, formed as a result of mutual volumetric recrystallization; with an increase in the forging force, the strength of the contact zone decreases, which is caused by a decrease in the proportion of the formed common grains. 3.

First, the phase-field simulation is performed to simulate the morphological change of the grain boundary ferrite to Widmanstätten ferrite.
The initial ferrite phase is set in the rectangular computational domain assuming that grain boundary allotriomorph ferrite is formed along a hexagonal austenite grain boundary.
For interfacial anisotropy, the following parameters and physical value are used: the average interfacial energy σ= 1.0 J/m2, the strength of anisotropy γ= 0.5, the mode number of anisotropy k = 2.
The grain boundary allotriomorph ferrite changes its morphology to Widmanstätten ferrite plates with carbon diffusion from a newly formed ferrite phase to austenite matrix.
In the microstructure A, the plastic stain concentrates around the initial grain boundary ferrite.

The results show that the size of SiC grains has no obvious growth.
Boundaries of Al2O3-TiO2 big grain are also shown in this image.
Countless nano-SiC grains were existed on the surface and boundaries of coarse Al2O3-TiO2 grains.
The light region is Al2O3-TiO2 grains and the darker are big grain boundaries where it had considerable nano-SiC grains before the treatment of making SEM test specimen.
Acknowledgements This work was supported by the Key Natural Science Foundation of Jiangsu Province under grant number BK2004005.

The results show that density is increased and grains are grown up gradually with the increasing sintering temperature without any microstructure defects.
It is a reason that the number of porosity of 8YSZ is least sintered at 1500℃.
And the hardness of 8YSZ sintered at 1400℃ is very close to one sintered at 1500℃, which is resulted by the effect of grain refining strengthening.
The reason of the decrease of fracture toughness is that grains are grown up quickly at high temperature.
The porosity of the ceramics sintered at 1300℃ is apparently higher than the ones sintered at the other temperature, and the grain size and distribution are not uniform; The voids content of 8YSZ sintered at 1400℃ is greatly less than the one sintered at 1300℃, and the grain size and distribution become uniform; The porosity of the 8YSZ ceramics sintered at 1500℃ is the least , and the grain size and distribution is the most uniform; However, the grains of 8YSZ sintered at 1600℃ become coarse, amount of the pore is closed or semi-closed by bulky grains, which makes it hard for gas in ceramics to discharge.

In general, it is well-known that the fracture strength of a large-grained sintered-ceramic is lower than that of a small-grained sintered-ceramic.
According to this model, the fracture strength of polycrystalline material is determined by the grain size, b, and the localized strength near the grain boundary.
In other words, the theory suggests that the strength is reduced when the bonding strength at the grain boundary is weak; when contaminants are segregated/ non-uniformly accumulated at the grain boundary, when there are interface defects at the grain boundary, and, naturally, when the grain size is large.
As it is clear from the Fig.9, residual silicon regions subjected to high stresses have a number of stripe shaped dislocations formed in an alternating white-and-black stripe pattern.
TEM observations were performed under such assumptions and a number of dislocations were confirmed in residual silicon regions of the high-strength reaction-sintered SiC subjected to high stresses.

The films sulfurized at H2S concentration of 20% have the biggest grain size of exceeding 2 μm and obvious columnar CZTS grains can be observed across the whole cross-section.
In Fig 1(a) except for the Mo (110) diffraction peak at 40.3 ° (according to JCDPS 42-1120), numbers of peaks corresponding to CZTS can be observed for all sulfurized films.
Therefore it is indicated that larger grains can be obtained at lower H2S concentrations.
Such result can be explained by the different number of CZTS crystal nucleus for films sulfurized at different H2S concentrations.
The flms sulsurized at H2S concentration of 20% have the biggest grain size of exceeding 2 μm and obvious columnar CZTS grains can be observed across the whole cross-section.

The measured data were cleaned up by a single iteration and grain dilation using a grain tolerance angle of 5° and a minimum grain size of 5 measurement points.
The grain size of pre-eutectoid ferrite was found to be about 5 µm.
Figure 3 presents the distribution of image quality number of sheets, annealed at temperatures of 695 °C.
The left sides of the IQ distributions were simultaneously shifted to higher numbers, corresponding to undistorted α-ferrite.
Misorientation at 60° is consistent with the misorientations between neighboring grains, bearing Kurdjumov-Sachs relationship with the parent grains (KS/KS).

The nano-sized BN grains with an average diameter of about 10 nm were homogeneously dispersed in nano-sized (about 70 nm) Si3N4 grain boundaries.
A number of small and large flaws were observed in the polished specimen surfaces of micro-composite; whereas noticeable flaws could not be detected in the polished specimen surfaces of nano/nano composite (photos not shown here).
The existence of nano-BN grains is expected to improve superplasticity and tribological properties.
The incorporation of nano-sized BN improve the superplasticity, this could be attributed to that (1) the BN could act as a lubricant for grain boundary sliding, (2) Nano-sized h-BN dispersions could inhibit the grain growth of Si3N4 by grain boundary pinning during superplastic deformation.
Nano-sized BN particles were homogeneously dispersed at the nano-sized (~70nm) Si3N4 grain boundaries.