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At the end of the incubation period, the exact number of colonies formed on the agar plate were counted and the corresponding CFU per ml were computed as follow: (1) Results and Discussions Characterisations of Ce doped ZnO powder Figure 1 demonstrates the XRD pattern of the prepared sample.
Sintering of precursor powder up to 1200oC produced Ce doped ZnO with the particle size of 2 – 4 µm (based on 50 randomly selected grains).
Due to partial diffusion of Ce, the nodules of CeO2 formed on the ZnO grains.
The presences of the rare earth dopant species restrict the abnormal grain ZnO growth during heat treatment and thus producing ZnO with uniform size.
This finding agrees with [4] in which stating that most of the rare earth dopants have grain growth suppression effect towards ZnO and encouraged the formation of uniformly grained doped ZnO.

Microhardness of the top surface was additionally measured at quite a number coating thicknesses.
The microstructures of 316L substrate majorly consisted of refined parent-grain structure and this formation usually occurs at 1150o C.
The microstructures of hardface/substrate interface showed columnar grains with significant epitaxial growth from the partly melted parent grains.
These grains have tendency to grow in the direction perpendicular to the interface.
Lowest value near the interface in the substrate region might be due to the coarsening of grains [11] and as no HAZ can be next to weld interface, the exact reason was not found.

Improved mechanical and physical properties of an Al-Si alloy as a well-known casting alloy is strongly dependent upon the morphology of silicon particles, Al grains and also type of intermetallics which are in turn a function of alloy composition, solidification rate and heat treatment.
Volume fraction changing between the eutectic and primary Al dendrites, changing in the size and shape of the silicon eutectic, finer α-Al grains and presence of smaller size of intermetallics with increasing cooling rate can be the reasons for these changes.
As illustrated in Fig. 8 a, the hardness numbers of the eutectic and α-Al phase increase as SDAS decreases.
Reduction of the number of hard intermetallics particles, lowering the plastic constraint effect and coarsening of silicon in eutectic are main responsible parameters for decreasing of eutectic hardness.

Ball milled organically modified bentonite/ cationic guar gum(CGG) can improve retention rate of paper-process reconstituted tobacco pulp obviously than organically modified bentonite/CGG because of smaller grains and better unigormity of ball milled bentonite.
The experimental determination of characteristic wave number of samples was very similar to the characteristic wave number of montmorillonite standard spectrum.
Ball milled organically modified bentonite/CGG can improve retention rate of paper-process reconstituted tobacco pulp obviously than organically modified bentonite/CGG because of smaller grains and better unigormity of ball milled bentonite.

Differences in grain structure and particle structure may result in streaks in the rolled plate.
The material was grain refined with AlTi3B1 rod.
Slices were cut normal to the casting direction, and prepared for investigation of grain structure.
The grain size and cell size was measured by a linear intercept method in an optical microscope.
Results and discussion The evolution of the grain size and the secondary dendrite arm spacing (DAS) was introductorily measured from the surface to a distance of 50 mm from the surface.

Recently, increasing numbers of papers are concerned with the use of rare earth elements in the manufacture of diamond impregnated tools.
Experimental As the main constituent metals for fabricating sawblade segments, the grain size of iron, copper, tin and nickel powders was less than 53 µm.
A kind of misch-metal (RE-Si-Fe) with grain size less than 10µm was used as RE additives.
Metal powders were blended together with diamond grains and RE additive for 1 hour in an ∞ shape rotary mixer.
Fig.6 shows the relationship between the protrusion height values of diamond grains and the contents of RE.

According to the calculation results, when the carbon content decreases to 0.03% (option No. 2), an increase in the number of quenching phases (granular bainite and acicular ferrite) is observed due to the suppression of the formation of such structures as ferrite and perlite.
An increase in the niobium content led to a 17% decrease in the grain size of ferrite (compared with the basic chemical composition, with a carbon content of 0.03%), but due to the low carbon content, part of niobium dissolves in the solid solution, which leads to a decrease in the ductility of steel.
An increase in molybdenum (options No. 12 and No. 13) stabilizes ferrite, which leads to an increase in its amount even at a carbon content of 0.03%, but on the other hand, an increase in molybdenum decreases the sensitivity to growth of austenite grain, which allows a reduction in the block size of granular bainite from 60 to 45 microns, and thereby improve the viscous properties of steel (impact work).
Increase the amount of niobium and molybdenum for grinding austenite grains in order to grind the structure and increase viscosity.
GB AF Fig. 2 - Scale X100, the structure is a mixture of acicular ferrite and granular bainite, with satisfactory resistance to hydrogen sulfide corrosion, with a ferrite grain size of 11-13 points, and the presence of single martensite grains.

In case of the yellow clay we found that the dominant grain size is below 20 µm, but there are also grains larger than 50 µm.
The gray clay has larger inhomogenity, the average grain size is larger due to the dominance of the large particles (>20 µm).
The surface of some of the larger grains collects the smaller ones.
See the indicated grains where #2 is covered and #1 is not that much.
As next step the additives were mixed into the prepared factory clay mixtures (yellow and gray clay minerals in ratio of 4:1), creating a number of clay based recipes with additive concentrations of 0, 4, 7 % wt. and with water contents between 15.57-16.67% wt.

But the deposition could not be cooled fast because of welding slag, the grains became thicker.
If stomatal inclusions are present in sufficient numbers, stress concentration is caused.
However, more carbides led to more latent heat released and grains became thicker, which early caused the cracking during wear process and shortened the service life.
Most of niobium was distributed at grain boundary of carbides and preferential direction growth of M7C3 carbides was impeded, which resulted in refinement of carbides.
Mao: Study on Wear Resistance of Composite Alloy Reinforced with Hard Alloy Grain for Coal Crusher.

According to the theory of particle coarsening，the grain growth and coarsening mainly depend on grain boundary migration and grain rotation process[13.14.15].
Table 2 Slow cooling temperature regression equation and boron extraction rate Furnace number Slow cooling temperature ranges Measurement points Average extraction rate 1500℃～1200℃ 1200℃～900℃ 1＃ 2＃ 3＃ 4＃ 1 T=1520-0.76t T=1408-0.55t 41.47 33.00 36.36 43.37 40.05 2 T=1516-0.88t T=1325-0.60t 55.79 59.85 42.06 46.64 51.09 3 T=1499-1.46t T=1381-0.99t 55.18 62.20 50.84 49.24 54.37 4 T=1494-2.39t T=1296-1.07t 60.03 63.39 47.20 58.13 57.14 5 T=1448-6.21t T=1234-0.78t 66.98 64.34 66.02 / 65.78（900） 6 T=1421-8.67t T=1227-1.15t 74.89 74.44 73.02 / 74.12（800） 7 T=1410-12.33t T=1326-1.19t 77.51 75.13 76.29 / 76.31（700） 8 T=1368-20.00t T=1168-1.90t 84.07 83.15 84.05 / 83.72（625） 9 T=1400-41.4t T=1175-3.05t 56.78 65.50 58.56 / 60.28（500） Fig. 6 The viscosity curve of boron-rich slag Fig. 7 The relationship of cooling rate and extraction ratio of boron Relationship between Boron Extraction Rate and Cooling Rate.
Vector-valued phase field model for crystallization and grain boundary formation [J].Physion,1998,D119:4155
Sharp interface limit of a phase-field model of crystal grains[J].
[15] U.Klement,U.Erb,K.T.Austl.Investigations of the Grain Growth Behaviour of Nanocrystalline Nickel[J].NanaStrnctured Matuiala. 1995, 6. pp. 581-584