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It was also reported, based on the simulation results, that the porosity and grain size of the source are related to the thermal distribution in a graphite crucible [8], but the effect of the porosity of individual powders on growth characteristic has not been studied.
It should be noted that the Si vapor concentration in the whole vapor phases (such as Si and SiC, Si2C etc.) strongly increased with decreasing grain size of the powder and the Si vapor concentration of porous powder become higher according to the Darcy's law [9, 10].
FWHM and wave-number of peaks around 970cm-1(a) at differently doped positions along the growth direction and (b) on 6H-SiC crystals grown with increasing thermal treatment time.
FWHM broadening and the wave-number shift indicate the N-doping variation.
The peak in the vicinity of 970cm -1 was relatively shifted toward the higher wave-number and was broadened when the treatment time is short due to a large amount of porous powders.

The initial activation number denoted Na is defined as the number to be full activated during charge/discharge process.
It can be concluded that heat treatment has little effect on activation number, but it influences the maximum capacity greatly.
Nakamura [13] thought lattice defects and small crystal grain boundaries were introduced by the rapid quenching ,thus more tetrahedral or octahedral interspace were reserved for the storage of hydrogen atoms in the crystal lattice, which enhanced the maximum discharge capacity of the alloy.
The reason why the retention of annealed alloy at 1273 K/8h is better perhaps due to low expansion rate, more homogeneous grain sizes and disappearance of internal stress[17].
But the capacity retention of the annealed alloy at 1373 K/8 h is 71.14 % which is lower than as-cast alloy.Nakamura [13] thought lattice defects and small crystal grain boundaries were introduced at the same by rapid quenching, more tetrahedral or octahedral interspace were reserved for the storage of hydrogen atoms in the crystal lattice.

The uniform distribution of the grains was appeared for all the films.
This may be due to slower gelation rate and/or presence of more number of coatings in order to reach to the preferred thickness.
The grain size of the films, deposited at a withdrawal speed of 4 cm/min, is revealed to be marginally improved, which may be related to the enhancement of the crystalline nature of the dip coated films.
In order to obtain the desired thickness, the ZnO films synthesized at 1 cm/min, have undergone maximum number of coatings in comparison to other withdrawal speeds due to its slower deposition rate.
The FESEM micrographs have found a uniform grain distribution for all the samples.

The number of 0.1ml in sample by microorganism will be counted [2]. 3.4 Monitoring indicators.
When the worm quantity grow up sharply, the number of protozo in water will reduce, water quality change badly.
When the worm number rises to more, lower aeration can make its content decreases.
When one gets the dominant advantages, another number will be less.
When the BOD load in the activated sludge is low, sludge retention time is long, and arcella number is likely to grow.

Then stress tends to decrease monotonically with number of cycles that is indicative for material softening.
OIM images were obtained with a step size of 120 to 170 nm and subjected to a cleanup procedure, establishing a minimal confidence index of approximately 0.1 and a minimal point number per grain of 8.
The dislocation densities were estimated by counting the individual dislocations in the (sub)grain/lath interiors.
Further increase in number of cycles provides symmetrical hysteresis loops with slightly increased thickness and retained plastic deformation, whereas stress amplitude decreases due to cyclic softening.
At eac=±0.6%, increasing number of cycles leads to an increase in retained plastic deformation and a decrease in stress amplitude.

After the desirable number of layers of the TBC is deposited the multi-layered coating is loaded in a compression chamber to form a densified layer before being sintered with an acetylene torch or furnace.
The applied pressure varies depending on the number of coating layers, typically between 10 and 40 MPa.
The composition of the monolayered coating is 50% ZrO2 - 50% Ni, which can be distinguished by the different grain structure.
Firstly, by applying constant heat flow, uniform heat expansion, and ideal boundary grain growth between particles is achieved thus reducing thermal stress induced during the thermal expansion process.
The main advantages of this technique are the low costs and the ability to cover large and curved surfaces, which are critical for a number of important practical applications.

Xu College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China Keywords: Brazed diamond grain, Interface, Resultant form Abstract.
In order to reveal the size, number, form and distribution characterization of resultant at the brazing diamond interface using Ni-Cr alloy, vacuum furnace brazing was carried out.
Furthermore, the size, number, form and distribution characterization of Cr3C2 and Cr7C3 were discovered and the brazing mechanism for diamond was illuminated.
In mono-layer tools, the size, number, form and distribution characterization of resultant at the brazing interface are key factors to determine the adhesion performance and service life.
Diamond Interface Ni-Cr Journal Title and Volume Number (to be inserted by the publisher) 153 0 20 40 60 80 100 0 500 1000 1500 2000 2500 Cr23C6 Cr3C2 Cr7C3 Diamond Fig.3 Appearance of resultant at the Fig.4 X-ray diffraction pattern of the resultant at surface of brazing diamond by SEM the surface of brazing diamond Fig.5 The form and distribution characterization of Cr3C2 and Cr7C3 by SEM Conclusion The present work has shown that Ni-Cr alloy could braze diamond grits very effectively through Cr3C2 and Cr7C3 which are produced by interaction between Cr atoms of Ni-Cr alloy and C atoms of diamond surface during brazing.

Also included in the category of growth defects generated at the moving growth front are threading edge dislocations (TEDs, the Burgers vectors of which have been analyzed [16]) aligned along the c-axis which often aggregate into low angle grain boundaries oriented parallel to {11-20}.
When the spiral hillocks broaden and impinge on each other, they can either elastically deform to accommodate the lattice tilts or a low angle grain boundary can be nucleated.
Many dislocations will naturally exist at the interfaces between the polycrystalline grains and those which have segments favorably oriented will expand under stress.
Some of these will propagate towards the polycrystalline exterior where they will run into other grain boundaries but others will penetrate in the form of half loops into the crystal interior.
Colin Wood) and by Dow Corning Corporation under contract numbers N0001405C0324 and DAAD1701C0081.

This method is using at joining of materials such as sheets, pipes, hollow profiles, where the thickness of material does not allow to make the drilling with enough number of threads.
In the place of thread we can see the pressed grains of tested material by roll forming operation - tapping.
The metallographic samples were oriented on macrostructure evaluation of created collars and bushings and their shape, roundness, in integrity and quality and then the microstructure evaluation of test samples as size and shape of the grains in the places of material deformation with magnification 100 x, 200 x and 500 x.
Based on the experimental work, we can conclude that Flowdrill method as thermal drilling method has following advantages [1,2,5]: § Reduction of the number of technological operations.
§ Reduction of the number of necessary equipment for manual or automated production.

The mixture for creating three samples with dimensions 40×40×160 mm was created from 450 g of fine grained granulated blast furnace slag Štramberk 380 (specific surface area 380 m2/kg), 180 g of sodium silicate (water glass) with modulus 1.6, silica sand with three different grain size 450 g from each grain size and 95 g of water.
Volume 43, Numbers 1-2, 2010, pp. 235-245, ISSN: 1359-5997