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The average grain size and density of SiC powder(fabricated by Acheson method) used in this study are 200mm and 1.76g/cm3.
Nishino et al. [4] reported that the number of small periodic peaks between the main peaks related to the double diffraction effect could represent the polytype of SiC crystal; 3 peaks for 4H-SiC, 5 peaks for 6H-SiC and 4 peaks for 15R-SiC.
The exact MPD (micropipe density) and EPD (etch pit density) numbers of SiC crystals grown by the conventional method and modified method were counted in etched images.

One nickel body diamond tool, with grain size of 126 μm, diameter of 24 mm, and wall thickness of 1 mm was selected (with a diamond concentration of 100%).
Acknowledgment This research was partially financially supported by the NSAF (Grant number: U1230110) and the National Science and Technology Major Project (Grant number: 2012ZX04010-061).

Introduction Current approach to the formulation of composite materials is based on the application of various fillers with grain or fiber character from natural and artificial resources.
The contribution of mineral additives lies in the optimizing of granularity as well, that is why number of inert additives, e.g. milled limestone, silica powder, are used.
The usage of commonly produced silicate types of cement, declared according to adequate standards, in CR it is CSN EN 197-1 [1], brings the number of complications for the formulation of advanced special cement based composites because of fundamental standard requirements related to their physicochemical properties.

Other test material were: Deng Ta PO 32.5R ordinary portland cement, medium sand, gravel with the grain size of 30 mm.
All the test piece and their numbering, also the reinforcement measure were listed in Table 2.
Table 2 Listing of test piece strength grade test piece numbering axial compression ratio reinforcement measure C20 1N1 — — 1N2 — — 1B-3 0.3 One layer BFRP 1B-4 0.4 One layer BFRP 1B-5 0.5 One layer BFRP C25 2N1 — — 2N2 — — 2B-3 0.3 One layer BFRP 2B-4 0.4 One layer BFRP 2B-5 0.5 One layer BFRP Test Result and Analysis Failure Phenomenon of Test Piece.Test results showed that: the tensile failure of FRP cloth caused the destruction of the specimen.

This could be due to the space holder with 50 wt % of SS 316 L that was too excessive than the stainless steel powder and the powder was unable to coat the grain particle of the space holder effectively.
Then, as shown in Fig. 1 (b) for 55 wt % SS 316 L, the struts were well-developed and the number of pores increased compared to 50 wt % SS 316 L.
Then, the number of open and interconnected pores has increased and the thicker and finer struts were produced comparing to other compositions.

A vast number of studies had been conducted in the past to further expand the functionality of ADI in term of the mechanical performance of these materials through transformation of their phase structures. [1-4].
Past study conducted using single step and two steps austempering heat treatment on un-alloyed ductile iron and nickel-molybdenum alloyed ductile iron at 260°C to 390°C found out that two step austempering processes resulted in higher yield and ultimate strength levels while maintaining reasonable levels of ductility, attributed by smaller grain sizes of bainitic ferrite and austenite [5-6].
Although the effect of alloying elements on the mechanical properties of austempered ductile iron had been broadly discussed before, there was least number of studies on the effect of niobium on the properties of ADI.

Generally, there are three standard procedures in crystal growth technology to achieve seeded growth of a new material: (i) spontaneous nucleation and growth of sufficiently large free-standing single crystal, (ii) use of grain selection phenomena in directional crystallization, (iii) utilization of a foreign single-crystalline material used as a large-area substrate for heteroepitaxial growth.
Near to the substrate side (Fig. 3c) a large number of cracks (dark linear features) are observed.
In layers thinner than 1 mm, the crystal quality suffers from large number of cracks which are produced at the substrate side because of the crystallographic mismatch between the SiC and AlN crystalline materials.

Accordingly, the tin oxide transparent conductive coatings with different film thickness, sheet resistance and resistivity can be obtained by relying on alternating or changing the solution concentration, the solution flow rate and the number of spraying coatings.
The SEM indicates crystal grain sizes of about 200mm are homogeneous.
Fig. 5 The variation of hemispheric emissivity versus sheet resistance for all the samples It can be considered from the discussion of electrical part that in the case of smaller thin films thickness, increasing films thickness or the number of layers can obviously improve electrical and infrared reflectance, but as far as the thicker thin films is concerned, the decrease in its resistivity is limited to a certain extent.

SnO2 thin film can be prepared by a number of methods, such as CVD [6], sputtering [7], spray pyrolysis [8], plasma and sol-gel methods [9].
It is impossible that grains have so huge size.
We think that the phenomena could find its origin in the large number of oxygen vacancies existing in the materials, and also in their interaction with the two antimony states of charge.

Increasing the annealing temperature resulted in a decrease in the internal stress in the grains and a reduction in the number of defects.
From the XRD analysis, in comparison with the pure ZnO films, the full width at half maximum (FWHM) of the (002) diffraction peak increases in the doped films suggests that doping the samples results in an expansion of the ZnO lattice with an increase in both the number of defects and the interfacial stress.