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However, the pores in the nanostructured TBC are nearly uniform circular, small average size, even distribution, and their number is far more than the conventional one.
The phonons are easy scattered by grain boundary, while the photons are susceptible to scattered by small pores, microcracks [13].
Thus increasing the grain boundary, the number of pores and microcracks is essential to reduce the coating thermal conductivity and improve the coating insulation effect.
For the plasma-sprayed conventional and nanostructured thermal barrier coatings, due to the different feedstock, there are a big difference both in the porosity, microcracks form and the number of grain boundaries, resulting in different heat insulation effect.
In addition, the nanostructured TBC owns smaller grains within number of grain boundaries than the conventional coating.

In micro-viewpoint the microstructure evolution during solidification process is considered, including nucleation (an increase in the number of nuclei), growth (an increase in the volume of the grain) and impingement [12].
Besides a more accurate solidification time and cooling curve, the models can also obtain data about undercooling, the grain number, grain size, nucleation, growth rates, etc., which cannot be obtained using macro-models.
(2) where N is grain number per unit volume and R(t) is the grain radius.
When the eutectic shell size reaches to a critical one, all the grain stops growth.
Eng; Graphite nodule numbering spheroidal graphite and malleable cast iron, Imono, 1973; 193

Grain quality was determined on the analyzer "InfraLUM FT –10M 07412 ".
Results in Table 1 show that in general, the CNT increase the number of grains per one ear and a yield per hectare, and this is not the result of soaking the seeds: it is namely the effect of CNTs.
Concerning the parameters of biological productivity we can conclude that the maximum peak in grain number was observed in the variant with unmodified CNTs, as well the number of grains per ear and weight of 1000 grains.
/sq. meter) Number of grains in 1 ear Weight of 1000 grains, g Grain yield, 100 kg/ hectare Protein % Gluten % Control/ – Н2О 195±1.03 28 ± 3 43 ± 1 16 ± 2 17,3 28,1 Control / + Н2О 197±1.25 32 ± 2 42 ± 0 17 ± 2 17,5 29,3 CNT/ no modifications 212±1.62 33 ± 2 51 ± 1 16± 1 18,8 34,5 CNT/ОН 236±1,39 30 ± 1 44 ± 1 16 ± 1 18,4 30,9 CNT/СООН 247±1,42 31± 3 48 ± 2 18 ± 1 18,7 33,2 The experiment was conducted in an abnormally hot and dry for this region summer, the average temperature during the study period was five to seven degrees above normal.
Phytopathological grain analysis showed that the unmodified nanotubes do not change the overall contamination of grain, and the treatment variant with CNT/OH-group reduces this parameter.

The last stage of polishing was carried out on suspension with grain size 0.25μm.
Finishing polishing was conducted on Al2O3 suspension with grain size equal to 0.25μm.
After 2.5 minutes of testing, grain boundaries are being partly uplifted (Fig. 3a), plastic deformation within the solid solution grain occurs locally, grains are not uniformly compressed.
Such crystal cell has small number of slip systems, which effects in small ductility of the material and this may accelerate material degradation [7].
The plastic deformation occurs only locally within the grains.

In detail, the following topics will be discussed: (i) description of the material behavior in varying processes, (ii) definition of material properties depending on alloying content, (iii) capability to describe whole alloy families, (iv) adjusting the model parameters by a small number of experiments.
(3) Carbon depending steady state grain size prediction was adjusted to the results of Sakai et al. [12] assuming that within technical relevant times the grain size is limited depending on carbon content and temperature.
Undercooling was calculated according to [14], whereas the final ferrite grain size was assumed to depend on the initial austenite grain size (AGS) linearly.
a) b) Fig. 4: Calculated grain size evolution, a) and flow stress, b) for C22 and C60 in a hot rolling mill.
Sellars and J.A.Whiteman, Recrystalllisation and grain growths in hot rolling, Metal Science, 187-194, 1979

Development of ultrafine grained and nanostructured materials helps other disciplines and has made a meaningful contribution to other fields especially materials and building construction.
In other word, however general knowledge regarding to ultrafine grained and nanostructured materials enhanced among architectural contributors, there is not enough technical knowledge among construction practitioners.
State of Issue Challenging issues which prohibited sustecture in achievement of its goals and objectives in case of adoption of ultrafine grains and nanostructures materials can be categorized as following issues.
Because they have primary information and be able to get full recognition, but construction practitioners as their position on recognition chart work is harder, number of them don’t have information about this product and are not aware of it benefits.
In other word, however general knowledge regarding to ultrafine grained and nanostructured materials enhanced among architectural contributors, there is not enough technical knowledge among construction practitioners.

The change in the contrast of STEM-HAADF images is associated with the atomic number of elements in particulate phases.
With the increase of Fe content the bright phase both at the grain boundaries as well as inside the grains is observed.
The results of chemical analyses performed in several grains of each sample and their grain size (average of 20 grains) are presented in Table 2.
So, the structure of the Fe-0 ribbons consist of the L21 grains and of very small grains of the 10-layered martensite located mainly on the grain boundaries of the L21 phase.
The small grain with size of about 200 nm located inside the L21 phase grain can be seen on the BF image.

But the number of cracks and crack width were different.
That means that the Ti/SnO2-Sb electrode (0.5mol% Er ) has smaller grain size than Ti/SnO2-Sb electrode (0mol% Er ), which could also be seen from Fig.1.
To solid catalysts, a smaller grain size is associated with more surface area and active sites.
Therefore, the reduction of grain size also is helpful for the electro-catalytic reaction (see Fig.5).
Considering the above mentioned grain refinement, this promotion may mainly accelerate the generation rate, but restrain the growth rate.

The capacitance value of this sample lies within 10-8 to 10-10 which represents that the electrical properties of the sample has shown bulk and grain boundary response.
Based on the plot, the capacitance values lie in a range between 10-8 to 10-10 Fcm-1 which has been interpreted as the grain boundary response [16].
It is in a good agreement with the capacitance plateau which can be observed at lower frequency region that represents the grain boundary effect.
Thus, it can be concluded that the electrical properties of the sample was controlled by the grain boundary effect.
A small number of pores can be visible from the micrograph pictures which is consistent with the relative density of the sample about 90.31%.

The Fe-Co fine-grained bulk alloys show the higher coeicivity than that of molten alloy.
Results and Discussion Fe-Co fine-grained bulk material.
The grain size of the water-atomized bulk body was smaller (< 50 µm) than that of the molten bulk body(about 100 µm).
The coercivity value for the 21 hours MA-treated specimen was 6.9 Oe, despite of very small grain size.
system per atom (Bohr magneton) versus the number of electrons was shown also in Fig. 6.