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The area of the ferrite grains was measured using an image system analysis and PRO-PLUS  software.
The grain size was taken as a square root of its area.
They are located mainly at the grain boundaries.
Polygonal ferrite contains a significant number of coarse Fe3C particles, which in some cases are remnants of decomposed pearlite, while in other cases are undissolved very coarse inclusions, formed probably during earlier stages of processing.
Formation of polygonised ferrite grains (Fig. 4f) indicates a recovery process taking place during annealing.

Four experimental filled tubular wires were used for surfacing of samples with a diameter of 2.4 mm designation and they are marked number 1 – 4 and their chemical composition is stated in Table 1.
The grain boundaries are lined with the pearlitic phase, as well as the troostite.
The grains are oriented in the direction of cooling of the cladding layer metal.
At the boundaries of the original grains, troostite is excluded and pearlite in a small volume.
In the area of ​​mixing, the structure is composed of fine-grained sorbite and troostite.

Table 1 The effects of different grinding times on fluorgypsum property Grinding time[min] Residue amount [%] Water demand for normal consistency[%] 0 60.5 40 10 22.7 34.5 20 10.3 31.5 30 6.8 30 40 5.6 31 50 5.1 32 60 4.9 33.5 The method of grinding treatment can change or destroy crystal lattice of fluorgypsum by increasing the lattice distortion and defects with the increasing of particles specific surface area and the irregularity of surface structure.[4-5] The grain size of fluorgypsum powders that was untreated or grinded only for a short time was big with a nonuniform distribution.
With the extension of the grinding time, the grain size of fluorgypsum powders diminished gradually.
However, when the grinding time exceeded a certain limit, although the grain size grew small, its specific surface area became very large.
The number of well grown dihydrate gypsum crystals increased significantly by the addition of 0.6% calcined alum, and the length-diameter ratio of dihydrate gypsum increased obviously with a shape of needle.
Compared with the sample with 0.6% calcined alum, the amount of dihydrate gypsum crystals in the samples with 0.4% potassium sulfate or 0.8% sodium oxalate was much smaller and there were a number of the unhydrated gypsum particles with the length-diameter ratio increased.

However, the number of commercially available Mg alloys is still limited especially for application at elevated temperature [3].
For engineering applications, alloys are created that contain a number of different elements, including Al, Zn, Mn, Si, Zr, Ca, Ag, Li, Cu, alkaline or rare earth elements.
With aging time increased at 180oC, second phases precipitated along the grain boundaries and the amount appeared to increase monotonically.
As shown in Fig. 4, with aging time increased, however, second phases were found to precipitate not only along the grain boundaries but also within the after aging for 48 hrs.
Similar results observed in ZA84 Mg alloys with boron and with increasing boron contents, amount of precipitates formed during aging treatment apparently increased and grain refinement also occurred.

The specimens were annealed in argon atmosphere, 1200-1800s and 723-748K to obtain grain sizes of 50-60µm.
Frequency of slip systems was defined as the ratio of the number of grains with slip lines to the number grains in observed areas.

Next, the dough was rolled at 3.0 and 2.0 roller distance for 4 times and 2 times, respectively, through the noodle presser, and finally cut into a number of Chinese dumpling wrappers, each of which was 2.0 mm thick with a diameter of 80 mm, by a cylinder made by the steel plate with a diameter of 80 mm[4].
As the temperature increases, the volumes of starch grains expand; starch grains absorb water in a large number; their molecular structures stretch; viscosity and transparency of the system increase.
If starch grains were able to completely swell when absorbing water and heated, and there was no molecular mutual association after starch gelatinization, the gelatinized starch will be very transparent[6].

Experimental results showed that coating burrs and the grain size increased when the duty cycle was over 40%.
Simultaneously, the copper coating deposited by pulse plating has lower surface roughness, smaller grain size and larger grain density than that by direct current plating.
When the cycle numbers are over 4, the coating deposited by direct current plating begins to bubble and then peeling.
However, the coating deposited by pulse plating is intact when the cycle numbers are 5.

Many methods are used to decrease the number and size of the porosities, but they cannot be eliminated completely [3].
Fig. 1 Sketch map of the specimen for the metallographic measurement of porosities Results and Discussion Fig. 2 shows that the porosities are mainly located at the grain junctions and their number and size are obviously larger in the as-cast specimen than those in the HIP specimen.
Fig. 2 Porosities in (a) the as-cast specimen and (b) HIP specimen Table 2 Evaluation of porosities in K417G alloy Samples (without HIP) Volume fraction (%) Samples (HIP) Volume fraction (%) Degree of healing (%) 1# 1.64 1# 0.25 85 2# 1.35 2# 0.33 76 3# 2.40 3# 0.26 89 4# 0.28 4# 0.07 75 5# 0.85 5# 0.11 87 6# 1.47 6# 0.32 78 Fig. 3 Size distribution histograms of porosities in (a) the as-cast and (b) HIP specimens The carbides in the as-cast specimen are blocky-shaped or long strip-like, which are unevenly distributed at the grain boundaries.
Fig. 6 SEM images of γ′ phases in the (a) dendrite cores and (c) interdendritic region in the as-cast specimens and in the (b) dendrite cores and (d) interdendritic region in the HIP specimens Fig. 7 SEM images of γ′ phases in the dendrite cores under the different conditions: (a) as-cast; (b) HIP Summary (1) The porosities are mainly located at the grain junctions.

The defects contained in SiC epilayers can be classified into two groups (1) crystallographic defects, including micropipes, closed-core screw dislocations, low angle grain boundaries, basal plane dislocations, hetero-polytype inclusions, etc. [1-3] and (2) surface morphological defects, including small growth pits, "carrot"-like grooves, comet tails, step bunching, scratches, etc. [3-6].
The PLM technique has been proven to map micropipes, screw dislocations, grain boundaries and stressed zones on a wafer-scale [2].
We have concluded that growth pits in an array are associated with threading edge dislocations since grain boundaries usually consist of an array of pure edge dislocations, which was confirmed by our recent investigations yet to be published.
Figure 2a shows a PLM image from one low quality commercial epi-wafer of an area with 13 screw dislocations, marked with numbers.
AFM images (Fig. 2b) from the same area revealed that, besides the 13 screw dislocation-associated growth pits without a nano-core, marked with a black circle and corresponding number, there are 6 extra growth pits with identical features (no nano-core), marked with squares that are not associated with screw dislocations.

The defect sphere is accountable for approximately 50% of total NC volume for the 10 nm grain size NC.
ZnO nanopowders was prepared with controlled grain size (10-70 nm) via a microwave driven hydrothermal process using different chemical reaction: Urea: ZnCl2+CO(NH2)2+3H2O → ZnO+2NH4Cl+CO2+H2O TEA: ZnCl2+2N(CH3 CH2OH)3+2H2O → ZnO+2(N(CH3 CH2OH)3• HCl) + H2O Alkaline Hydroxide: ZnCl2+2KOH+ H2O → ZnO+2KCl + H2O Ammonia: ZnCl2+2NH4OH+H2O → ZnO+2NH4Cl + 2H2O.
ZnO NC grain size (BET system), morphologies (scanning electron microscopy) and structure (xray diffraction) was controlled and described in [5].
This result suggests in the ZnO NC there are a number of different OH positions.
Though the number of urea lines appears in ZnO NC spectrum the additional bands (for example 829 cm-1, 1380 cm-1 1501 cm-1 and 1554 cm-1) were observed indicating that ZnO NC did not simply covered by urea molecules.