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Sputtering parameters for the deposition of CIGS (sample numbers as in fig. 4).
This phase is liquid at temperatures higher than 500 o C [9], and it is known to be one of the main conditions for the big-grained surface morphology formation of CIGS layers [10].
When the Ar pressure was constant, the grain size of CIGS formed near the interface with Mo back contact was rather small becaming larger towards the top surface.
For sputtering processes starting at high Ar pressure or high substrate temperature for first stage (higher than 500 o C) homogenous cross-section structures with large grains were obtained.
Acknowledgements This work was supported by Fundação para a Ciência e Tecnologia, Portugal (FCT), through a research grant number POCTI/CTM/38721/2001 and a PhD grant number SFRH/BD/19516/2004.

As we see that, the surface morphology on PSiNs surface of small particles with uniform grain size fill in pores form by ZnO nanoparticles like in Fig. 2(d).
It happen because the substantial grain growth and formation of single phase ZnO happen [5].
A large grain size of ZnO nanoparticles on PSiNs substrate was calculated, indicating that the grain become more uniform and bigger in size on the sample signifying an important role in reducing the defect inside the znO thin film.
In general, the sharp peak also can be used as an indicator to proved that sample possess larger grain size compare to other samples.
According to that finding, when the number of nitrogen in ZnO structures increase, the numbers of free carrier also increase.

The results showed that the average grain size of samples fabricated is obviously refined, finer a-Al grain obtained at the bottom than the top of the ingots.
But the addition of the Al2O3 nanoparticles did not significantly influence the shape factor of the primary a-Al grains [7].
In addition, the long solidification time and high melt temperature of the melt here result in a small number of defects such as shrinkage and porosity in the solidified microstructure (Fig. 2a).
The fracture surface presents a concave and convex grain shape, which belongs to the typical intergranular fracture characteristics.
There are also a large number of cracks on the fracture, which may be caused by stress concentration caused by uneven deformation during the tensile process.

In the ZnO resistor valve, the grain boundary layer of unit thickness determines the potential gradient of the ZnO resistor valve, and the grain boundary layer of unit thickness can be changed by the size of the crystal structure, which in turn affects the potential on the ZnO resistor valve.
Its unit the formula of thickness varistor voltage is [6] (1) Among them: U1mA/mm is the varistor voltage per unit thickness (is potential gradient), N is the number of grains per unit thickness, Ub is the breakdown voltage of a single interface, generally a constant (2~3V), and d is the average grain size, U0 is the voltage drop in the crystal grain of the ZnO resistance valve.
It can be seen from the formula (1) that when the ZnO crystal structure is larger, the unit varistor voltage is smaller, and when the number of crystal grains N is larger, the unit varistor voltage is larger.
According to the formula, when the grain boundary thickness tB is constant, the dielectric constant increases with the increase of the crystal size.
Generally speaking, the forbidden band width of the crystal can affect the grain boundary barrier, and then affect the non-linear characteristics of ZnO resistor valves, and with the increase of the forbidden band width, the grain boundary barrier will increase, and the non-linear characteristics of ZnO resistor valves will be more obvious.

The clear grain boundary is obtained (Fig.4 (a)), and precipitates of α phase were observed on grain boundaries and especially inside grains.
At the same time, the bigger of the β grain size, the lower of the ductility.
Volume 49, Number 5(1997)38-41
Volume 56, Number 2, 2004,pp. 40-44
Semiatin,et al, Aging response of coarse- and fine-grained β titanium alloys.

Effect of Long Term Operation on Degradation of Material of Main Gas Pipelines Pavlo Maruschak1, a, Roman Bishchak2, b, Igor Konovalenko1, c, Abdellah Menou3, d and Janette Brezinová4, e 1Ternopil Ivan Pul’uj National Technical University, Ternopil, Ukraine 2Ivano-Frankivsk National Technical University of Oil and Gas, Ivano-Frankivsk, Ukraine 3Office National des Aéroports (ONDA), Académie Mohammed VI, AIAC, Aéroport Casablanca Mohammed V, Nouaceur, Morocco 4Technical University of Košice, Košice, Slovakia amaruschak@tu.edu.te.ua,blaboratory22b@gmail.com, cgrozny.17@bk.ru, da.menou@onda.ma, ejanette.brezinova@tuke.sk Keywords: damage, pipelines, microstructure, hydrogenation, fracture stress, grain boundaries Abstract.
A number of crack-like laminations oriented mostly in the longitudinal direction are found on the external pipe surface (pointed with an arrow).
Apart from “large” cracks, a number of microcracks are found on grain boundaries.
Obviously, cracks nucleated on grain boundaries and propagated under the action of stresses by the “stress – corrosion” scheme [6].
By means of analysis of the I image the quantitative characteristics of damage were calculated: the relative area of damage and number of corrosive pits.

The final grain size was about 100 µm.
This fact can be explained by surface diffusion which drives a significant amount of the deposited tracer atoms to the single GB in case of a bicrystal versus a distribution over a large number of GBs in a polycrystal.
Gust: Fundamentals of Grain and Interface Boundary Diffusion, (Wiley & Sons LTD, Chichester, New York, 1995)
McLean: Grain Boundaries in Metals (Clarendon Press, Oxford, 1957)
Herzig: Your question refer to a figure in which the grain boundary velocity is the function of the temperature of Cu grain boundaries in presented in Arrhenius form (Interface Science 9 (2001) 357, Fig. 2).

This forms a fine-grained austenite, which turns into a highly disperse martensitic structure, unattainable by traditional methods of heat treatment.
Material and Methods of Research Surface plasma hardening was subjected to band wheels made of carbon steels of grade number 2, the chemical composition of which is given in Table 1 (GOST R 52366-2005).
The initial structure is a mixture of ferrite and pearlite grains with a volume fraction of each phase of 20-80%, respectively.
As a result, a fine-grained austenite is formed, which turns into a highly disperse "structureless" martensite [14].
As a result, fine-grained austenite is formed (grain point N14, dsr = 22 μm according to GOST5639), which turns into a highly disperse martensitic structure, unattainable by traditional methods of heat treatment.

(5) here,a is natural number,b{1,2,,LZC-1} is ZC serial radical exponent,s=0,1,,LZC-1,d is any integer,for simplicity, suppose d=0[10],then signal with pilot is:
(15) Obviously,SNR is function of channel grain H(n),if SNRthreshold is determined, and , what means：
(16) then,the threshold Hthreshold is determined,so the chosen symbol is proper as long as its grain is higher than this threshold.
Simulation Results Simulation in this paper is based on LTE uplink SC-FDMA,for simplicity,U=2,carrier bandwidth is 5MHz,FFT sampling points M=512,Lcp=M/8,Doppler frequency shift is 50Hz, subcarrier number is 300,subcarrier mapping is localized FDMA,modulation is QPSK,bit error rate threshold is 0.005,twice iterative computations,1000 times of Monte Carlo simulation on each SNR node,channel is typical city macro cell model,simulation results are shown as Figure 4 and Figure 5.
Figure 5 shows system BER curves of two kinds of estimation methods,when SNR is low,estimation accuracy can not be improved because the signals chosen from estimator1 are not enough,but estimation precision rises when the selected symbol number and SNR increasing, obviously,result from estimator2 is better than that from estimator1, and estimator2 of R-LS is 5dB better than estimator1,such two algorithms nearly have error basement when SNR is close to 18dB,grains of such two algorithms have almost linear change and have no obvious rise when SNR is higher, Conclusion Each user in SC-FDMA system occupies only part band and sub-channel has time-frequency related properties,an SC-FDMA channel estimation based on pilot is proposed, from the above theoretical analysis and simulation results, such channel estimation algorithm is feasible in LTE uplink system,because it not only improves channel estimation precision,but also reduces system BER.The only defect is that such algorithm becomes complex

It can be seen that the average grain size of each samples has no obvious difference, but the porosity of group 2 is less than the other two groups.
It is already known that the voltage-gradient mainly limited by the grain size and the number of barriers [9].
And the arrangement of grains is tightest.
The number of the grain boundary by unit thickness is larger.