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As the sample heated at 1250℃, the microstructure seemed to become denser, and a large number of crystals are precipitated and distributed evenly, with the shape including columnar, massive and lamellar, ect..
Fabrication of cordierite–mullite ceramic composites with differently shaped mullite grains[J].

Nodes stress distribution of center-surface During quenching, to the total number of heat, the center area takes away the most heat, but the conner areas play a key role to the cooling capacity per unit area.
Inhomogeneities of icrostructures and micro-orientations in cold-rolled high purity Al columnar grains, The Chinese Journal of Nonferrous Metals Vol.15(2005),p.1173

This has created an increase in the number of researchers interested in waste materials.
EDX Analysis of the Grains in Fig. 3 (a.

The decrease in optical transmission can be related to the loss of light due to oxygen vacancies and scattering at grain boundaries.
Excitonic peaks likely to appeared for undoped ZnO which indicates the number of defects is reduced and the quality of the films is improved.

Welding an aluminum possesses a number of properties that make it different compared to welded steels which are: (i) high thermal conductivity, (ii) high thermal expansion coefficient, (iii) low melting temperature, and (iv) the absence of color change as temperature approaches the melting point.
Fine grain oxide was found to develop in protective parent metal and non protective flake-like oxide was found covered the entire area of fusion metal.

As the depth of cut increases, number of particles decreases by 50%.
The contamination was evaluated in terms of the number of abrasive grains embedded on the cut surface.
This ability is very important for the analysis since the number of contamination will be counted when the picture of the surface is captured.
(iv) The result shows that for Zone A (Primary Impact Zone) contains quite a number of contaminants.
Zone B (Smooth Zone) has fewest numbers of contaminations and Zone C (Deformation Wear Zone) contains the largest number of contaminations.

Under these conditions, the convective flux to the surface of the propellant will be enhanced, which in turn enhance the local Reynolds number.
This effect will further accentuated in the case of star grain downstream of sudden expansion where the star points generate multiple flame fronts.
Figure 4 is demonstrating the axial total temperature variations of DTMs at different time intervals revealing the flow unsteadiness causing the variations of Reynolds number during the starting transient phase, which alter the convective heat flux and the ignition sequence / flame spread in a rocket motor with non-uniform port geometry.
We inferred that when the upstream port is narrow the convective flux to the surface of the propellant will be enhanced, which in turn enhance the local Reynolds number.

The main methods to enhance physical and mechanical properties of hard-alloy plates are improvement of manufacturing technology, including production of fine-grained alloys and microalloying, as well as applying composite coating by vacuum deposition, which allows to increase the tool resistance 1.5 to 2 times.
Alloy grade Number of passes Micro-hardness under load 1,96 N Wear on the front surface Hf, mm Wear on the back surface Hb,mm Т15К6 (source) 5 1554; 1542; 1543; 1554; 1543 0,46 0,24 Т15К6 (nitriding) 5 1815; 1787; 1787;1748;1715; 0,08 0,04 Т14К8 (source) 5 1515; 1465; 1465; 1465; 1487 0,29 0,27 Т14К8 (nitriding) 5 1648; 1787; 1687;1648;1615; 0,1 0,06 The analysis of Table 5 suggests that, after nitrogenizing at Т = 1,200 °С, the cutting wear of quick-change plates for cutters made of T15K6 and T14K8 hard allows decreased on average 3 to 5 times, whereas the micro-hardness increased up to 30 %.

Therefore, C-S-H /PCE nanocomposites can improve the early strength of mortar effectively since it can lower the barrier of nucleation of the products, promote the nucleation and inhibit the growth of large grains effectively.
In addition, a large number of studies have shown that the superplasticizer can have an impact on the C-S-H impact, but the influence of superplasticizer used on the preparation of calcium silicate hydrate effects need further study.

As the driving force increases, both the number density of nucleant particles and the permitted quantity of bainitic ferrite increase, which together lead to the formation of an extremely fine mixture of bainitic ferrite and retained austenite [10,11].
FWHM broadens due to grain refinement [38], thus, it can be concluded that austempering at a lowe temperature leads to a decrease in the thickness of bainitic ferrite plates.
These include the formation of ultrafine-grained microstructure [5], stress- or strain-induced transformation of high-carbon retained austenite to martensite (or deformation hardening) [44], and solid solution hardening mainly by carbon [45].
Patent number GB2462197;2010
Bhadeshia, Properties of fine-grained steels generated by displacive transformation.