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The fly ash used for concrete will be of an average grain size, determined during the grinding experiments by Šulc and Svoboda [3].
Technical quality conditions number 18 [5] states that the minimum air content in the fresh concrete with grain size up to 16 mm for exposure class XF4 is 4,5%.

The size of prior austenitic grain boundaries of the steels are almost the same (about 20μm).
These microstructures consisted of a wide lath-martensite structure matrix and fine dispersed MA-like phase, which is a mixture of narrow lath-martensite and retained austenite and isolated on the block, packet, and prior austenitic grain boundaries.
The numbers of voids at the break section in steels B and C were the same as that in steel A, although the size of the voids in steel B were larger than those in steels A and C.

However, there is a limited number of publications concerning the hybrid effect of Al2O3 and graphene on aluminium-based composites [13, 14].
The preparation procedure started with mixing the aluminium powder using ball milling process to reduce the grain size and ensures the dispersion of reinforcement through the matrix phase.
The commercial alumina powder (Al2O3) used in this work has a grain size of about 10 μm.

A number of external influences — physical (e. g. low and high temperature), chemical, and mechanical — affect the structure during use [2-3].
After blasting, the grains of the aggregate were exposed.
The aggregate grains were intact and were tightly anchored in the cement putty (see Fig. 5).

-12 -9 -6 -3 0 3 6 9 12 Y/×(10-4m) Be SS 4 -4 -3 1 -2 4 0 1 2 3 -1 3 2 Fig. 2 Sketch map division nuits(The number is units,s sign) x /(×10-4m) Fig. 1 The diffusion couple C1 0 Be SS C2 In a few hours, the diffusion distance is about hundreds of micrometers, therefore, divided only finite element in very small zone near the Be/SS bonding interface (shown in Fig. 2).
The higher the heating temperature, the faster the diffusion and the better the bonding joint strength, but recrystallization and phase transformation may take place at high heating temperature, which leads grain growth and composition segregation and strength decline in the bonding joint.
But diffusion bonding temperature is generally above recrystallization temperature, and may lead grain growth in longer holding time, especially the holding time should be controlled for the joints on posslble forming brittle intermetallic compounds which reduce the joint performance . 0≤ t≤7200s （3） 100 o Concentration curve of Fe l Concentration curve of Be Distance, x /μm Atom concentration,C/% a 90 -100 100 -25 -50 -75 0 75 50 25 80 70 60 50 40 30 20 10 0 Fig.5 The concentration profile of Be and Fe under 1023K/60MPa and different time, (a)1800s, (b)3600s, (c)5400s Atom concentration, C/% o Concentration curve of Fe l Concentration curve of Be Distance, x/μm c -100 100 0 -25 -50 -75 75 50 25 100 10 90 80 70 60 50 40 30 20 0 o Concentration curve of Fe l Concentration curve of Be Distance, x/μm Atom concentration, C/% b -100 0 -25 -50 -75 75 50 25 100 90 80 60 50 40 30 10 20

Number of specimens from the bar for hardness test was three, and mean value of specimens was collected.
An elevated brittleness usually occurs, at medium carbon steels, from an excessively high temperature of reheating which promotes coarsening of austenitic grain.
However, the pearlite fraction is small and the grain size of steel is fine, as mentioned above, thereby it is considered that heating process applied during hot forging is reasonable.

Table 2 Hardness number at different locations of defect samples Locations Hardness type Carburized layer Transitive layer matrix A HV 698 597 490 HRC 58 53 46 B HV 724 559 376 HRC 59 51 35 According to the above analysis, the fatigue life of drill tool can be enhanced by controlling smelting, rolling, forging, heat treatment, machining, etc.
Forging plays a role in homogenization and avoid coarsening of grain.
Forging plays a role in homogenization of grain size.

The discrepancy may due to (i) the bandgap of films measured by PL technique is slightly smaller than that determined by UV-VIS spectrometer [16], and (ii) the variation of optical bandgap is influenced by the grain size of the films, that is, the large bandgap values as the decreasing the grain size of the films [16].
Acknowledgements We thank the National Science Council of R.O.C. for financial assistance under Grant number NSC97-2221-E-151-004 and NSC98-2221-E-151-024.

Recent studies showed that the crystallographic textures exist in the optical grade free-standing diamond films and the distributions of grain orientations strongly affect the properties, performance and reliability of the diamond films.
Diamond films are polycrystalline materials, in which the grain orientations may be randomly distributed or preferentially distributed to form {hkl} fibre textures.
It can be found in diamond octahedron that the number of <100>, <111> and <110> growth directions is 3, 4 and 6 respectively.

As fatigue tests under the IP cycling, tensile stress occurs at high temperature, where the cohesive strength of the grain boundary is low, so the occurrence of negative mean stress is reasonable.
In all of these loading conditions, the crack mainly initiated at grain boundary and then propagates in a transgranular manner.
Under high magnifications, -0.01 -0.005 0 0.005 0.01 εm (mm/mm) -400 -200 0 200 400 σ (MPa) 1st 2nd 5th 10th IP TMF -0.01 -0.005 0 0.005 0.01 εm (mm/mm) -400 -200 0 200 400 σ (MPa) 1st 2nd 5th 10th OP TMF -0.01 -0.005 0 0.005 0.01 εm (mm/mm) -400 -200 0 200 400 σ (MPa) 1st 2nd 5th 10th IF 0 1000 2000 3000 Nf (cycle) 0.004 0.006 0.008 0.01 ∆εm/2 (mm/mm) IP OP Fig. 5 Strain amplitude with number of cycles for IP and OP TMF tests.