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The AFM photograph reveals that there is an increase in the grain size with the increase in film thickness.
We believe that the decrease of 2q-FWHM mainly results from the increase of BFO grain size and the reduction of strain in the films.
It is worth noting that the number of fringes increases by increasing the film thickness which is a common observation.
The decrease in energy band gap with increase in film thickness might be due to the increase in grain size of the samples, as suggested by the XRD, section (3.1).
The grain sizes of the films were found to be increased with the increase in film thickness.

The microstructures are fine-equiaxed grains.
Along alpha- grain boundaries, especially at triple points micro cracks can be seen often (Fig. 3a and b).
The cracks were formed mainly at grain boundary triple points in the lamellar microstructure zone (Fig. 3).
The high stress concentration at grain boundary triple points induced by grain boundary gliding may be responsible for the failure.
The large grain size of alpha-phase may be responsible for that single alpha phase zone is a no-go area for forging of gamma-TiAl alloys.

A broad grain size distribution is observed for TiZn2O4 phosphor.
Sample Number TiO2 ZnO Eu2O3 1 1 1 0.05 2 1 1 0.1 3 1 2 0.05 4 1 2 0.1 5 2 1 0.05 6 2 1 0.1 7 3 1 0.05 8 3 1 0.1 9 3 2 0.06 10 3 2 0.1 For PLE and excitation wavelength dependent PL measurements, a 1000 W Xe lamp was used to generate white light.
The highest PL peak intensity is observed for stoichiometric ratio of 1 to 1 between TiO2 and ZnO (experiment number 1 and 2).
The plan view of SEM image displays polygon shaped (mainly hexagon) grains along with some elongated grains with diameter between 1.5 and 12 mm.
The wide variations of grain sizes are generally observed for solid state sintering.

The deviation from the parabolic law is again a real "nano-effect", because after dissolving a certain number of layers (long time or macroscopic limit), the interface shift returns to the parabolic behaviour independently of the input parameters (see Fig. 5b).
It was observed that grain boundaries, GBs, close to the exposed surface migrated.
Large-angle grain boundaries were found in high density inside the clusters.
Bimodal grain boundary structure, filling up GBs by GB diffusion.
Beke, Grain boundary diffusion in thin films with a bimodal grain boundary structure, Thin Solid Film 520 (2012) 2362-2367

Metallographic examination was performed, the grain structure parameters were determined, and diffraction radiography for the analysis of phase composition and texture and electron microscopy for the analysis of the grain structure parameters and the substructure were used in the study.
The increase in nitrogen content, with a constant base chemical composition of steel, brings about an increase in the level of stress and, correspondingly, a finer grain after recrystallization.
; d, d0 - grain size after deformation and hardening at a given temperature; 1a - volume of recrystallized grains below 95 % and the absence of a maximum in the hot compression diagram; 1b - volume of recrystallized below 95 % and the occurrence of a maximum in the hot compression diagram; 2 - volume of recrystallized above 95 % and the absence of a maximum in the hot compression diagram.
Increasing the deformation rate (to 10 s -1) results in an increase in the number of structural defects, thus facilitating dynamic recrystallization and, as a consequence, the removal of cold work effects - a drop in σmax.
The fraction of recrystallized grains increases with increasing deformation time (decreasing deformation rate) and with increasing temperature.

Scanning electron micrograph shows that the grains exhibit a plate like morphology and possesses fine particle size.
A great number of agglomerates can be seen in the powder which is typical of combustion synthesis products [14].
Fig 2(b) shows that the grains of SBT pellets exhibit a plate like morphology.
It was also found from the SEM micrograph that the grains of different sizes are homogeneously distributed.
Similar grain morphology was observed in SBT prepared by other methods.

During thin film growth process, sputtering is a non-balanced films growth,and there are components’ ups and downs in films, plus space limitation, grain size and grain squeak, all of this cause much stress at the grain boundaries and a number of defects such as dislocations, bond breaking and so on.
According to the Scherrer formula, grains have a tendency to grow up.
In general, the growth of grain size has negative influence on its gas-sensing features.
And films appear corresponding crystal and crystal type changes after anneaed at 700℃.When use the gas sensitive character of ZnO film, it often needs specific crystal type and corresponding grain size, and ZnO film still exists clearance atomic Zn and oxygen vacancy after annealed at 700 ℃. 2.2.2 Acetone gas sensitive characteristics of different annealing temperatures We also studied the effect on gas sensing properties of acetone after annealed at higher temperature.
Grain size control and gas sensing properties of ZnO gas sensor, Sensors and Actuators B 66(2000)277–279 [7] Lv Jianguo and effect of annealing on crystallization properties of ZnO thin films [j], Journal of semiconductors, 2004,24 (7), 729~735

It is distributed on the grain boundary, which can enhance the grain boundary strength and drag the grain boundary slip at high temperature.
The heat-resistant intermetallic compounds distributed along the grain boundary contribute the most to the high-temperature strength.
The higher the thermal stability of the second phase, the finer the grain, and the higher the dispersion along the grain boundary, the more it can block the deformation of a-Al solid solution at high temperature, and the better the heat resistance of the alloy.
Al7Cu4Ni phase tends to be skeletal, so when designing the composition of Al-Si piston alloy, it is necessary to increase the number of a13cuni phase as much as possible to obtain better high temperature properties.
The banded intermetallic compounds distributed at the grain boundary are the most effective to improve the high temperature properties of piston alloy.

* Ehsan Ghassemali, Email: ehsa0005@ntu.edu.sg, Tel: +65-84312143 Raulea et al. [3] investigated the effects related to the ratio of aluminum grain size to sheet thickness in two experiments, uniaxial tensile tests in which the grain size was kept constant and the sample thickness was varied, and bending experiments in which the grain size was varied for constant specimen thickness.
The results showed a decrease of yield stress with a decreasing number of grains over the thickness up to one grain over the thickness.
Beyond this i.e., for grain sizes larger than the thickness, the yield strength tends to increase by increasing grain size.

Figure 1 Sandstone whole-rock mineral X-ray spectra in Daqiang Mine Figure 2 Mudstone whole-rock mineral X-ray spectra in Daqiang Coal Mine Figure 3 Argillaceous sandstone whole-rock mineral X-ray spectra in Daqiang Coal Mine Figure 4 Conglomerate whole-rock mineral X-ray spectra in Daqiang Coal Mine Figure 5 Coarse-grained sandstone whole-rock mineral X-ray spectra in Daqiang Coal Mine Figure 6 Fine-grained sandstone whole-rock mineral X-ray spectra in Daqiang Mine Figure 7 Sandstone clay mineral X-ray spectra in Daqaing Coal Mine Figure 8 Mudstone clay mineral X-ray spectra in Daqaing Coal Mine Figure 9 Sandy mudstone clay mineral X-ray spectra in Daqaing Coal Mine Figure 10 Conglomerate clay mineral X-ray spectra in Daqaing Coal Mine Figure 11 Coarse-grained sandstone clay mineral X-ray spectra in Daqaing Coal Mine Figure 12 Fine-grained sandstone clay mineral X-ray spectra in Daqaing Coal Mine The results show that: In sandstone
, quartz, albite and calcite crystal mineral’s content is higher, the numbers are 22.8%, 27.1%, 29.4%.The left 20.7% are clay minerals, which includes 32% kaolinite, 28% achlorite content, and 40% smectite mixed layer.
The mineral compositions of the coarse-grained sandstone are quartz (36.2%) and plagioclase (31.5%), followed by a small amount of potassium feldspar (2%) and a small amount of calcite (1.7%).
The mineral composition of fine-grained sandstone, quartz (20.1%) and calcite (48.8%), followed by part of the plagioclase (14.8%) and a small amount of potassium feldspar (2%).
Clay minerals in fine-grained sandstone account for 14.3%, contained in the clay mineral montmorillonite, and their content is up to 80%, followed by a small amount of kaolinite (4%), chlorite (8%) and green / fudgelayer (8%).