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At present, the method of chemical oxidation is more common, which generally used large scale and high-purity graphite as raw material, that is graphite grain size for 200-1190µm and fixed carbon content is more than 99%, sulfuric acid as intercalating agent, potassium permanganate as oxidant [7].
In addition, a large number of polar groups, such as hydroxyl, ether and carboxylate groups, on the surface of the EG layers were easily processed.

Samples with different number of layers are achieved by dip coating in the slurry, thereafter a drying at 100 °C for 1 h is conducted.
Large grain growth by annealing of Ag-covered Bi2Sr2CaCu2O8+d thin films and its application in the fabrication of intrinsic Josephson junctions, Supercond.

Nevertheless, Magnesia hydration is a key concern in refractory castable processing, it is due to the volumetric expansion that follows magnesia hydration is related to the density mismatch between the magnesium oxide (ρ= 3.5g/cm3) and its hydroxide, magnesium hydroxide(ρ= 2.4g/cm3), the reason above can result in cracks or even explosion during the first heating-up.There are a great number of studies describing the MgO hydration behavior in castables systematically[2,3].
According to the MgO surface model, there is inevitably straight steps, normal corners, and simple kinks in the MgO surface, a roughly 2.5-fold volumetric expansion appear followed by MgO surfaces interactions with water(Fig.2), when the MgO particle size distribution is determined in water, the hydration of MgO is carried out by the contact of this oxide with liquid water, so the reaction of MgO +H2O→Mg(OH)2 is happened, that is to say, MgO undergoes an expansive hydration reaction as a result of the different densities between the magnesium oxide (ρ= 3.5 g/cm3) and the corresponding hydroxide formed (ρ= 2.4 g/cm3), Mg(OH)2, also known as brucite[4-6] In fact, however, MgO grains used as determined sample are polycrystalline and could generally be described as several single crystals bonded together.

With the rapid development of concrete technology, increasingly higher technical requirements of modern concrete sand, especially with high strength and high performance concrete to aggregate are strict, fewer and fewer number of natural sand can meet their requirements, not even.Thus, the development of new sources of sand (artificial sand) is imperative [1-2].
Maximum grain size of coarse aggregate is 31.5mm.

It can be seen from the quantity statistics on failure elements at different loading stages (in Figure 3) that the number of failure elements at the CE stage is quite large.
And then the tensile cracks are continuously produced on the grain boundaries, which is consistent with the conclusion mentioned in Reference [12].

The further EDX spectra inspections showed higher C/Cr/Mo peak between grains, as shown in Figure 4.
Inden: The Journal of Corrosion Science and Engineering Vol. 6 (2003), Conference Paper Number H043 [9] B.

Interconnect is a critical component in SOFC as it functions to bridge structurally and electrically a number of sequentially stacked unit cells.
The micrograph shows sharp ant discrete stereo-granular structure, and each grain should be an oxide compound as the SEM/EDS analysis displays significant oxygen content.

Introduction Colloidal processing techniques provide the possibility to manufacture complex-shaped ceramic products with minimal number of detrimental defects, which require the use of stable slurries with high solid loadings [1,2].
The grain size of the sintered body falls in the range of 1.5~3.0μ m.

With such a thin barrier film, even minute structural defects like cracks, voids or grain boundaries, can adversely affect its barrier performance.
Fig. 2 shows the total displacement (TD) of the single atoms calculated from anrnrTD N n∑= −−= 1 |)1()(| (1) where N is the number of time intervals in the computation, r(n) is the position of the metal atom at interval n and a is the dimension of the periodic cell. 0 200 400 600 800 1000 1200 1400 0 0.5 1 1.5 2 Time (ps) Speed (m/s) Cu Ta Fig. 1: Speed of Cu and Ta atoms in linear amorphous polymer (LAP) It is noted that although the mass of Ta atoms is only twice that of Cu, the TD of Cu is 4 times that of Ta.

This model is corresponding to emission of thermal carrier across grain boundary where the conductivity is anticipated to be linear with temperature [12].
The carrier concentration in this temperature range is number of ionized donor liberated from impurity levels.