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In addition to a low investment compared to other additive manufacturing techniques, thanks to machines and components directly derived from welding industry [2], the use of an electric arc as a source of fusion offers a number of processing advantages, compared to electron beam and laser [3].
In fact, a large number of projections is generated by the 1007 line; these projections sometimes merge with the deposit increasing its width locally.
On the contrary, by depositing at high wire feed speed, the liquid metal previously deposited does not spreads over the substrate generating an actual stick-out of deposit slightly lower than for low wire feed speed, and a drop deposition distance gets shorter, eliminating numbers of projections.
This phenomenon indirectly contributes to the irregularity of the printed deposit for low WFS by increasing the number of projections, since these projections attract the initiation of the electric arc towards it during deposition causing a deviation of the deposit, resulting in wavy deposits as shown in Figure 4.
Lu, Wire arc additive manufacturing of AZ31 magnesium alloy: Grain refinement by adjusting pulse frequency, Materials 9 (2016) 823-836

It should be noted that with the increase of Yb doping concentration, the diffraction peaks are broadened, suggesting a systematic decrease in the grain size for the samples.
Figure 5 shows the Sample Atomic % Ti O Yb Undoped TiO2 40.46 59.54 0 Yb 0.5 mol % 38.02 61.18 0.80 Yb 2 mol % 37.24 61.89 0.87 Yb 8 mol % 36.71 62.32 0.97 50 n Undop e d TiO 2 500 nm 200 nm TiO2:Yb (2%) 200 nm TiO2:Yb (2%) TiO2:Yb (8%) 200 nm 30 35 40 45 50 0 10 20 30 Particle size (nm) Number of particles φ = 40.6 nm σ = 2.9 nm TiO2 20 30 40 50 60 0 10 20 30 40 50 Particle size(nm) Number of particles 2 % Yb φ = 33 nm σ = 3.23 nm 20 25 30 35 40 0 10 20 30 40 50 Number of particles Particle size (nm) φ = 27.5 nm σ = 1.4 nm 8 % Yb C N O Ti Ti keV 0 10000 20000 30000 40000 50000 0 5 10 (a) C N O Ti Ti Yb Yb keV 0 10000 20000 30000 40000 50000 0 5 10 (b) Table 2.
When the particles of interest contains heavy elements, high-angle annular dark field scanning TEM (HAADF-STEM) is the right choice to determine their existence in the matrix, as the contrast of the HAADF image is strongly related with the atomic number of the elements [23].

While it is well-known that the co-deposition of 5 mass% or more of the lead into the tin electroplated film can suppress the whisker growth [2], and several studies have been conducted and a number of theories put forward regarding the role of the lead in suppressing the whisker growth, many details of the process are still unclear.
(a) Under the ultrahigh vacuum, (b) Under the ultrahigh vacuum with the removal of the oxide film by argon ion etching, (c) Under an ambient atmosphere In the tin films, growth of whiskers over 30 µm in length were observed for 2400h and the number of whiskers per the same surface area increased, but there was not much difference between the nodular hillocks for 24h and 2400h after the plating, although a little growth was noticed.
However, the number of nodular hillocks in the tin-10mass%lead films was increased with the passage of time, compared with the tin films.
In Sn-10mass%Pb electrodeposited film (Fig.4 (b)), whiskers within 20 µm in length as well as the massive nodular hillocks were also observed, however, the number of whiskers per the same surface area as before, as well as whisker growth rate remarkably decreased, compared to the tin electrodeposited film.
The lead which exists at the interface between the tin film and the substrate chiefly diffuses into a tin film toward the surface at high speed along the grain boundary.

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].

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.

Small, stand-alone electronic devices which are growing in numbers in next generation smart cities, can be powered by scavenging energy from sources which would otherwise remain unused, such as mechanical vibrations.
Therefore a number of studies in past few years have found the operation and utilization of ceramic-polymer based piezoelectric composite material for energy harvesting based on the principles of piezoelectricity.
Cao, “Electromechanical Properties of Fine-Grain, 0. 7 Pb (Mg 1 / 3 Nb 2 / 3 ) O 3 -0 . 3PbTiO 3 Ceramics,” pp. 1–4, 2004

The advantages of this method are the reduced number of simulations tests that must be done and precision of the obtained results.
In mini and micro deep drawing process, the quality of the final part is affected by multiple aspects as: material grain size and orientation, friction coeficient, speed of the deformation process, blank holding force, tools geometry and so on.
The presented method is a valuable algorithm for designers of the mini forming process tools; · in conclusion Taguchi method has the advantage that it can be used to optimize processes containing a large number of input parameters, it is simple, robust and leads to good results.

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].

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.