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Indeed, no spallation is observed on the surface but a double structure : an outer layer composed of small and fine oxide grains and an inner layer with with columnar grains.
These oxide grains exhibit an α-Al2O3 structure; which is consistent with the XRD results.
However, the grains do not appear in contact but separated by small voids.
Even if we have, once again, an impression of large grains separated by voids (Fig. 4c), we can also notice on the top of these oxide grains, many needles indicative of the formation of θ-Al2O3.
This great number of nucleation sites should also explain the small size observed for the oxide grain and the uniform grain distribution on the surface (Fig. 5).

Titanium causes to reduce the corrosion of weld since titanium prevents the formation of chromium carbide in the grain boundaries [5, 6]. 2.
of 1 to 6 were used to investigate the effects of voltage, the tests numbers 7 to 12 were used to consider the effects of duration of pulse, the test numbers 13 to 18 address the effects of pulse diameter, the test numbers of 19 to 24 discuss the effects of frequency, and the test numbers 25 to 28 address the effects of welding speed and the test numbers of 29 to 32 discuss the effect of gas flow rate.
In later pulses, the sizes of the grains are reduced.
Figure 12: The microhardness distribution for the sample number 8 6.
The high voltage may result in hot crack formation in the grain boundary.

NCD films have lower hardness than MCD films due to the presence of amorphous carbon in the films, moreover, small grain size leads to high grain boundary density that also favors surface hardness reduction, thus they are liable to polishing[5].
Murakami’s reagent attack WC grains and roughen the substrate surface; as while, Caro’s acid oxidizes the binder to soluble Co2+ compounds, thus reducing the surface cobalt concentration[9].
After each deposition, the diamond coated interior-hole surface is polished with both diamond grits (1μm) and plasma in order to eliminate the sharp edges of diamond grains.
It can be seen that the interior-hole surface is covered by a continuous layer of fine-grained MCD film with diamond grains of ~4–5 μm in size, accompanying with a large amount of small diamond crystallites.
It is also noted that the slight shift in wave number of diamond peak from 1332 cm-1 can be owing to the residual compressive stress in the film.

Fig. 1(a) shows the case of without nitrogen doping, a continuous diamond film is observed with uniform diamond grain having size of few ten nanometers.
This is in good agreement with the SEM results, according to which, the aggregation of diamond grain on the film surface caused by CN species.
Raman spectra of NCD:N film deposited with 20% nitrogen doping shows a weak peak of sp3 bonding at 1332 cm-1 which seems to be overlapped by D-band peak (at ~1350 cm-1), demonstrating that the film possesses small diamond grain size and relative high ratio of grain boundaries.
Also, Raman spectra and XPS showed that the grain boundary was increased with increasing the nitrogen ratio in the plasma.
Acknowledgement This work was financially supported by the mail research projects of the National Science Council of Republic of China under Grant numbers NSC 101-2221-E-027-009.

The grain size tends to decrease as Ge coverage increases.
From the shape of the SiC (111) peak it is possible to quantify the grain size in each layer [4].
The r-c FWHM is similar for all the samples (around 0.7º) except for the sample Journal Title and Volume Number (to be inserted by the publisher) 3 with 1 ML of Ge (1.1º), as shown in Fig. 1(c).
The reduction of the grain size seems to induce a larger dispersion of the misorientation of the grains, as shown by the increase of the r-c FWHM.
As Ge predeposition was increased, the SiC layers exhibited lower residual strain and smaller grain size.

Table.1 Chemical composition of the base metal and weld metal Sample number Chemical composition（wt%） Element C Si Mn S P Cr Mo V Base metal near the crack 0.12 0.24 0.68 0.012 0.014 1.11 0.22 0.22 Weld seam near the crack 0.09 0.52 0.77 0.020 0.025 0.98 0.37 0.24 Metallurgical microstructure observation.
Observation showed that the crack originated at the melting line then propagated along coarse grain zone where lots of intergranular cracks were found.
Fig.5 Crack originating along melting line Fig.6 Lots of cracks within coarse grain zone SEM observation.
It can be found from Fig.7 that the crack in coarse grain zone was transverse type and consists of a cluster of holes that form a macrocrack when connected.
Those cracks locate only within coarse grain zone and belong to reheat crack.

A significant number of studies covers the magnetite oxidation process [4-14].
However, the ore grains in contact with oxide liquid form solutions with it.
The reducing gas can reach hematite or magnetite grains only when full reduction of the iron oxides takes place in the adjacent slag layers.
In this case, there is ore-slag type binder between the grains of the iron oxides.
The structure of the pellets represents the assembly of cracked slag inclusions with practically no binder between the ore grains.

Austenite-ferrite steels normally contain 0.02 % C and 0.25 % N and various levels of Cr, Ni and Mo but there are a number of variants of these steels with different alloying element levels.
Sigma phase precipitates first at points of contact between grains, then at grain interfaces and upon longer time at higher temperatures on non-coherent grain boundaries and inclusions within grains.
Fig.8 As-cast state of duplex steel, location A, 100x Fig.9 Sigma phase along grain boundaries, location B, 1000x Microstructure contains particles of secondary phases (Fig. 9) which precipitated non-uniformly.
The specimen contains areas where the particles are scarce and other regions where the austenite-ferrite interface is delineated with them (Fig. 10, 11) Fig.10 Sigma phase along grain boundaries, location C, 1000x Fig.11 Sigma phase along grain boundaries, location C, 5000x After measuring chemical composition by EDX it was found that they are probably the sigma phase.
Specimen 5 contains small isolated particles on the grain boundaries (Fig. 14).

Very limited numbers of additive manufacturing systems are capable of producing the multi material printing.
Optical micrographs of printed samples (a) presence of micro pores and (b) grain boundaries.
In addition to grain morphology obtained, the crystallographic preferred texture was observed in additive manufactured metal parts.
This leads to the grain growth adverse effect on mechanical properties of the material.
The surface topography of the alloy captured by optical metallurgical microscope revealed the unique microstructure with columnar grains.

The positive role of the PES program has been gaining the attention from an increasing number of nations.
Despite of so much attention paid to PES systems, the number of successful cases is quite small, especially when environmental services are provided at the national or global level [59].
The price of the subsidized grain (unprocessed) and cash are provided by the central government.
In 2007, a new round of grain for green project was started.
The experience of implementing market transactions, increasing the number of funding sources and promoting the local development can be used for reference in ecological compensation.