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Quartz sand with a maximum grain size of 2.5 mm was used as aggregate.
Limestone powder with mean grain size of 21.9 µm was used as an admixture to AAS mortar.
Fracture surface of sample which was heated to 600 °C shows a typical structure of AAS binder which is mainly composed of calcium aluminosilicate gel with lots of microcracks formed due to internal drying shrinkage, the number of which increases during heating.

We express sincere thanks to a number of organization such as DSI Inc, USA, Trans Tech Publishers, Switzerland and Dayananda Sagar University, Bangalore, India for supporting student participation from various countries.
Hong, Lin Geng, Goroh Itoh, Yuyuan Zhao Interfaces, Grain Boundaries & Structural Characterization Techniques D.
Hiramatsu, Lei Lu, Kei Ameyama Ultra Fine - Grained Materials R.

In comparison with conventi -onal materials, nanostructure materials possess superior mechanical and physical properties owing to the fine grain effect, sub-size effect,surface effect and quantum effect of nanometer particles, so addition of nanoparticles into conventional materials has been believed to be a potential way to improve the toughness of ceramics.
Table 1 Chemical composition of the tested cutters (wt%) Tool Ti (C,N) TiN WC Mo Ni C A 49 0 15 15 20 1 B 44 5 15 15 20 1 Table 2 Cutting parameters, tool life and failure mode of all test groups Group number Vc (m/min) f (mm/r) ap (mm) 200 0.1 0.5 300 0.1 0.5 I 400 0.1 0.5 200 0.2 0.5 300 0.2 0.5 II 400 0.2 0.5 200 0.3 0.5 300 0.3 0.5 III 400 0.3 0.5 Results and Discussion Microstructures of the Test Materials.
The tool B has higher transverse rupture strength than that of tool A attributed to its finer grains, while lower hardness (14.7GPa) may be due to the relative lower hardness of TiN compared with that of Ti (C,N).

Table 1: Chemical composition of the S355 steel used and maximum content of elements C% Si% Mn% P% S% Actual composition, bulk material 0.061 0.017 1.14 0.012 0.0072 Actual composition, near surface 0.058 0.017 1.11 0.011 0.0071 Maximum content [5] 0.23 0.05 1.60 0.05 0.05 Microstructure, examined using optical microscopy, was of ferritic-pearlitic type with homogeneous grain size 8 evaluated according to EN ISO 643 standard.
Looking at the S-N curve of the 10 mm sheet, the S-N curve slope is quite shallow, which may be affected by the fact that early breaks, i.e. points on the left side of the diagram, occurred in base material unlike points on the right side, which corresponded to breaks in weld or fusion zone after large number of cycles, even more than 5 million.
It is evident that the surface microstructure is finer than that of the subsurface and bulk material, which is in general for fatigue resistance favourable, but it contains almost pure ferrite unlike bulk material, where cementite is distinctly located along grain boundaries.

The presence of significant amounts of nano-crystals with a grain size larger than 1 nm can be ruled out, too, as a peak width of less than 5° is expected in this case.
This research project has been supported by the European Commission under the 7th Framework Programme through the 'Research Infrastructures' action of the 'Capacities' Programme, NMI3-II Grant number 283883.
Priolo, Crystal grain nucleation in amorphous silicon, J.

Figure 1 shows that the crystallite size reaches its highest value at damp heat time of 999h, which leads to a decrease in grain boundary scattering due to charge carries [5].
Because the grain boundaries of the lattice structure trap oxygen atoms, the number of oxygen vacancies also decreases. 300 400 500 600 700 800 90010001100 Wavelength (nm) 0 20 40 60 80 100 Transmittion (%) As-deposited 168 h 336 h 672 h 999 h (a) 300 400 500 600 700 800 90010001100 Wavelength (nm) 0 20 40 60 80 100 Transmittion (%) As-deposited 168 h 336 h 672 h 999 h (b) Fig. 5, (a) AZO and (b) GZO films versus each optical transmittance spectra at different time of damp heat treatment.

Ultrafine (Ni/Mn)CuZn ferrite with uniform composition, small grain size, and narrow size distribution are expected to realize low temperature sintering and attain ideal magnetic property at the same time [2, 3].
OHmnClNHOmHOMeCOnHMeClOHOCNH 2 4 242 22 24224 )1(2 )( −+++↓⋅→⋅+⋅ (1) where Me are Ni, Mn, Cu, Zn and Fe ion. m and n are the number of hydrate .
It is possible to sinter at low temperature by means of its small grain size, large surface area and high surface free energy.

The size of most powders was about 10-30µm and a large number of oddments were presence as shown in Fig.1a.
Fig.2b is high magnification of Fig.2a, which shows some MWCNTs (shown by arrows) were inserted the Al2O3 grains and several Al2O3 grains were glued together.

Fly ash is a fine collection of waste from the combustion of coal in thermal power plants, spherical, very fine grain size.
For the first time, the role of fly ash is the fine-grained backfill pore structure of cement stone.
Acknowledgements This research is funded by Vietnam National University HoChiMinh City (VNU-HCM) under grant number C2014-20-17.

As illustrated schematically in Fig. 3, a number of iron oxide nuclei can grow with different crystallographic orientations in the synthesis condition of the present experiment.
The iron and oxygen molecules needed to form iron oxide grains (shells) on the surface of iron acetylacetonate vapor are provided from iron molecules inside the precursor and the reaction gas (O2) outside the precursor respectively.
Two shells of hollow nanoparticle grow with different orientation and meet together, forming grain boundaries between each nanocluster nuclei.