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In order to produce a useful voltage a number of cells (depending of the application) have to be connected in series.
Since these alloys natively presents excellent corrosion resistance and high metallic strength due to their structural and chemical homogeneity, there is no grain boundaries or other defects.
A number of nickel based amorphous alloys made of cheap, common metals were proposed to be used as bipolar plates also [20].
Since most of the metal ion transport into the solution is through grain boundaries and other structural defects, the amorphous nature of the tapes renders the passive film more protective In the present case, due to a lower Nb content a preferential dissolution of the Ni ions from the tapes surface take place [31].

This method is applied to a Ti-Zr system to demonstrate the usefulness of this technique for evaluating the diffusion coefficients at large number of compositions.
This long time of annealing was an essential step to increase the grain size up to 3 mm and thereby minimize the contribution of the grain boundary diffusion.
The standard PAP correction program was used for atomic number (Z), absorption (A) and fluorescence (F) corrections [18].

Modelling The homogeneous nucleation frequency of crystals (I s ) in a liquid (amorphous) matrix can be obtained from [6]:      − = RT G exp aND I * 2 vns ∆ (1) where Dn is a diffusion coefficient for nucleation, Nv is the number of atoms per unit volume, a is the atomic radius, T is the temperature and R is the gas constant.
Hopfler et al. [18] have measured the diffusion of B in FeB grain boundaries.
Lacking data of B diffusion in an amorphous alloy and because grain boundaries can be considered as a twodimensional model for an amorphous phase [19,20], these data have been used for B diffusion in the amorphous matrix.
Because of the huge number of intermetallic compounds in the binary and in the ternary systems, a full assessment of the Al-NiCe system is not yet available.

A large number of researches have been focused on the effect of hydrogen as an alloying element on phase compositions, development of metastable phases, and kinetics of phase transformations in titanium alloys.
The Ti-6Al-4V-0.1H alloy also shows a simple XRD pattern of HCP α phase and BCC β phase, but the number and intensity of β phase peak increase (Fig. 2b).
The δ hydride decomposes and fine recrystallized α grains are formed, but δ hydride also precipitates in βH phase of Ti-6Al-4V-0.5H alloy and fine recrystallized α grains are developed in transformed β of dehydrogenated Ti-6Al-0.5H alloy.

Similar observations of cell proliferation and differentiation of human-osteoblast-like MG63 cells have been reported elsewhere in which cell number (proliferation) and differentiation were shown to be affected by surface roughness.
According to Nieh et al., [4] superplastic behaviour has been shown to occur in many materials including metals, ceramics, intermetallics or composites, multi-phase materials with uniform or non-uniform microstructures exhibiting relatively coarse (20 µm) to ultrafine (30nm) grain sizes that have isotropic or anisotropic grain shape, size or orientation.
Furthermore, it is of interest to note that a number of the components of medical scanning devices are made from aluminium alloys by superplastic forming and Figure 3 shows some examples of typically formed components.

The film consists of contacting grains of round shape with a diameter up to 15 nm.
Sample Sn concentration [%] Film thickness [nm] Composition Root-mean-square roughness [nm] A 0 213 α-Si 0.32 B 14 604 Si1-xSnx 1.36 C 19 285 Si1-xSnx 0.43 D 17 261 Si1-xSnx 0.32 E 40 336 Si1-xSnx+β-Sn 26.8 F 20 270 Si1-xSnx 0.23 At the 604 nm thickness of grown Si-Sn film (sample B), the rms roughness increased to 1.36 nm, which indicates the coagulation processes of individual grains in the film (from 15 nm to 30 nm) and increasing their height.
It is believed that a large number of broken bonds on the boundaries of nanocrystals form a high density in the tails of states of the silicon band gap.
This indicates an increase in the number of silicon crystallites with dimensions of 8-10 nm, but not an increase in the average size of the silicon crystallite.

Diffusion also takes place along line and surface defects which include grain boundaries, dislocations, inner and outer surfaces, etc.
There are several reports indicating that the CS route has been successfully used for preparation of nano-materials and is accomplished in number of countries [100].
The grain size of Li-doped Y2O3:Eu3+ film is larger than the Y2O3:Eu3+ film.
The SEM image reveals that the YPO4:Eu3+ nanophosphor has nearly a number of cobblestone spherical particles with agglomeration and grain size less than 100 nm.
Hou, T.T Jia, Controlling of grain size with different additives in Tm3+:Y2O3 transparent ceramics, J.

There were a number of studies identifying that the anaerobic filter system, using natural materials as support media, had a high efficiency for treatment and biogas recovery of agro-industrial wastewater containing high organic contents.
Tapioca products include tapioca starch and dried tapioca chips/flakes/grains.
There were a number of research studies mentioning that physical surface properties of burnt corn cobs allowed bacteria to substantially adhere to the surface [14].

IBS consist of a mixture of BCP grains with different particle sizes, commonly smaller than granulates in order to obtain a rheologically suitable paste along with hydrosoluble polymer.
Therefore, inflammatory response, bone ingrowth, and BCP degradation were different according to the grain size.
Pore diameters must exhibit values of hundred microns in size [56,70,71] and a number of designed pore interconections to verify in the shortest possible time a bioresorption of the scaffold and the subsequent new bone formation (Table 1).
Other methods such as mechanochemical [107] or hydrothermal synthesis [108] allows to obtain Si substituted CaP with small grain sizes, high strains levels and, consequently more reactive.
Anyway, this substitution leads to BCPs with higher solubility, more crystalline strains, smaller grains sizes and higher number of triple junctions.

Thus, the standard form of PSO could be denoted as: (1) (2) where is called inertia weighting factor and used to better control the scope of the search, R1 and R2 are two independent random numbers selected in each step according to a uniform distribution in a given interval [0,1] and C1 and C2 are two constants which are equal to 2 in this standard version.
The random number was multiplied by 2 to give it a mean of 1, so that particles would “overshoot” the target about half the time.
One approach to reduce the elapsed time is to make use of coarse-grained parallelization to evaluate the design points.
Furthermore, this part of the computational work is scalable, i.e. increasing the number of particles will cause the amount of evaluations to increase proportionally.
In this approach, PSO searches the real number space to determine the new position of each particle.