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On the other hand, most defects known from regular crystals (like vacancies, substitutional or interstitial foreign atoms, dislocations, grain boundaries etc.) also exist in quasicrystals.
These values were considered as indicating a point-defect mechanism for peak A, but a collective motion of a large number of atoms for the high-temperature peak B [5, 20, 23].
Since about 90% of the long modulus increase takes place in the nanostructured range with grains < 20 nm [33], it might be dominated by the recovery of relatively weak, disordered regions between the clusters or grains, which develop to sharper and mechanically stronger grain boundaries only gradually.
For comparison, the dashed and dotted lines show "coarse-grained" Ti53Zr27Ni20 heated to 878 K [7, 33] and a Debye peak with an assumed activation energy of 0.4 eV, respectively.
This tentative discovery of some "critical" grain size for a sharper quasicrystalline order generally fits to the above-mentioned viewpoint that with decreasing icosahedral grain size, the distinction between amorphous and quasicrystalline (and also crystalline) structures becomes less and less sharp when local icosahedral order is present everywhere.

Formation of the ternary compound by irradiation determines the mechanical properties of the alloy, because the appearance h-phase results in an alloy with a grain size of less hardness alloys.
It is believed that such characteristic as wear resistance always increases with decreasing of grains size. 
Thus, the formation of the ternary compound in consequence of the irradiation is responsible for the changing of mechanical properties of the alloy so far as the occurrence of the h phase leads to acquisition of alloys with a smaller grain size [1] and increases the solidity of alloys.
Pores along the edges of the cleavage planes disappear and decrease their number interfacial carbide bunch.

(1) ΦTCk is the calculated value of the thin film quality factor from the k-th experiment which contains j performance of i factor. n is total experiment number which contains j performance of i factor.
Under such temperature, the average free diffusion length is longer and leads to a larger grain size.
The rough surface will increase the absorption of the photons, but reduce the scattering as the grain size increases.
Some research indicates that crystal grain may exist in amorphous thin film with the deposited time and growth of thin film thickness.
The introduction of hydrogen atom can reduce the structure stress of the ITO thin film, increase the number of oxygen vacancy, and reduces the roughness of the surface and resistivity.

It has broad promotion and application prospects, and can be widely used in chemistry, biology, grain and other fields.
Liquid color detection is very important in chemistry, biology, grain, oil and other fields.
The disadvantage is only to display numbers and special characters.
For example, in the determination of grain’s fatty acids, it needs to detect the color change of the solution.

The main objective of the present work was to study the influence of the textured grain in the mechanical behaviour of the modified surfaces.
These variations are normal within sputtering depositions: i) the increase in pdep enhances the collisions in the interelectrodes space of the sputtered atoms decreasing the number that reaches the substrate; ii) the substrate bias promotes the sputtering process in the growing film, thus decreasing its thickness and iii) the presence of the reactive gas decreases the amount of Ar on the deposition chamber thus diminishing the amount of ions able to promote sputtering and, consequently, the amount of species that reach the substrate.
Some authors with similar results attribute the instability and the high friction coefficient to the presence of more (200) oriented grains [14].
In the present study also the poorest results were obtained when an increase of (200) oriented grains was observed.

It was further observed that samples that have higher Cr content possessed finer grains with martensitic structure.
The other parameters like number of weld-passes which represent the number of layers were varied in single layered depositions and double layered depositions.
The addition of Cr significantly slows down the rate of recrystallisation in low carbon steels thus improving the grain size also it tends to make oxide layers which protects against corrosion [11, 15, 20].
The optical micrographs for the specimens are shown in figure 3 below, showing the fusion zone and the grain structure of the coatings.
Uniform distribution of carbides with fine grain structures can be observed in the micrographs. 4.

The thicknesses of the films have been varied by varying number of pulses with a repetition rate of 10 pulse/sec.
The thickness of the films was varied varying the number of laser pulses on the target.
The observed much lower mobility in ZnO/Si films than ZnO/c-plane sapphire films are mainly due to the higher scattering in polycrystalline grain boundaries of the non uniform grains of ZnO/Si films. 200 400 600 800 1000 0 20 40 60 80 100 % Transmittance Wavelength (nm) ZnOtemp:500 o C ZnOtemp:600 o C ZnOtemp:700 o C 3 4 5 6 7 0 500 1000 1500 2000 2500 ((((ααααhνννν))))2222 Energy (eV) ZnO temp:500 o C ZnO temp:600 o C ZnO temp:700 o C Fig2: UV absorption spectrum a) Transmittance b) (αhν) 2 vs Energy plot (a) (b) Fig 3.

As grinding continues, removed chips may stick in the space between abrasive grains and deteriorate the wheel's cutting ability.
A focused laser with high power density will cut through the wheel removing both cutting grains and clogged chips.
The wheel grain, bonding material and the embedded metal, in addition to their melting points, will have other properties that vary between them.
Grains of grinding wheel are transparent under normal light.
Damaged wheel surface after laser cleaning Changing the laser pulse frequency, which means changing the number of laser pulses on the same wheel surface, can also control the level of laser irradiance.

With the number of passes, the zone where strain exceeds the saturation threshold gradually fills up the entire cross-section.
These are boundaries of coarse grains and twin-structure elements.
The structure is not uniform with the average grain ≈ 90 nm (HV value ∼ 4.1 GPa).
With further e increase from 4 to ≈ 10 the NC state is formed with the average grain size d ≈ 80 nm.
Symp. on Ultrafine Grained Materials, The Minerals, Metals, and Materials Society, Warrendale, PA, 2002, pp. 297-301

Introduction Polycrystalline solids with grain size of less than 100 nm are known as nanocrystalline materials.
The properties of nanocrystalline materials are very often superior than those of conventional coarser polycrystalline grain counterparts.
The structural parameters such as crystal phase, lattice constant, grain size, average stress and strain, orientation, and many others are strongly dependent on deposition parameters, which are the pH of electrolyte, deposition technique, current density, substrate, as well as the type and amount of additives included in the electrolyte.
Each experiment was carried out using a plating bath that contains nickel sulphate hexahydrate as the source of nickel, ferrous sulphate heptahydrate as the source of iron, nickel chloride hexahydrates as complexing agent, boric acid as the buffer, and sodium saccharine as grain refinement agent.
Another observation is that reduction in crystallite size increases the amount of dislocation density because of the presence of a larger number of grain boundaries.