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Only a limited number of studies have been performed on the use of high calcium fly ash (Class C) as it has low wettibility with molten Al alloy.
The average grain size of Al6061-fly ash composites is smaller than that of Al6061.
The number of corrosion sites observed in Al6061 (Fig 6(a)) was distinctly lower than those present in the microstructure of Al6061-fly ash composites (Fig 6(b), Fig 6(c) and Fig 6(d)).
As a result, the number of corrosion initiation sites increases.

Relevant data show that the number of newly started highway projects in our country reached 111 in the first half of 2009, with the construction mileage reached 12 000 km and the total investment will reach about 700 billion Yuan.
Freeways have been built in China have reached 75 000 km by the end of June of 2009.[1] The results obtained by investigation of domestic freeways show that the pavement appeared large numbers of cracks one or two years after it was open to traffic, and the highest cracking rate reached 640m/1000m2.
The Formation and expansion law of Semi-rigid asphalt pavement reflection cracks A large number of studies have shown that the emergence and development of reflective cracking is caused by the base movement (dislocation), and these moves are primarily originated from the temperature changes, moving vehicles and the combined effects of both.
Pavement structure and its parameters refer to the actual pavement structure of Zhumadian-Luohe section in Beijing-Zhuhai highway, structural form: AK-16A type of medium-grained asphalt concrete thickness 4cm, AC-25I-based coarse asphalt concrete thickness 5cm, AC-30I-based coarse asphalt concrete thickness 7cm, cement stabilized crushed stone layer thickness 20cm (actual thickness: 40cm), cement lime stabilized soil thickness 36cm, the total thickness is72cm, shown in Fig. 1.

These alloys have effectively no real grain structure, the total atomic disorder leads to the lack of magnetocrystalline anisotropy.
(ii) besides the alloy formation, the mechanical alloying induces a large number of structural defects and the progressive amorphisation of the alloy.
(iii) finally, the presence of a thin layer of benzene, obviously non-magnetic, on the powders surface will leads to a decrease of the number of magnetic atoms in the mass unity reducing thus the global saturation magnetisation of the powders [9].
Acknowledgment This work was supported by CNCSIS – UEFISCSU, project number TE-2012-3-0367.

Compared to the influences of precipitation hardening, other hardening effects like the grain size are usually neglected.
According to this theory the distance in the glide plane depends inversely proportional to the square root of the particle number density in the slip plane.
The particle strengthening according to [2, 3, 14] is calculated under usage of the Taylor Factor M, mean radius r, shear modulus G, Burgers vector b, a constant parameter β, mean obstacle strength F between obstacle and dislocation line and the total number of particles Nv as σp=Mb2 G Nv rβ F3/2 with F=i Fi NiFi
The increase in temperature leads to a significant decrease in volume fraction of the precipitation phase, Fig. 3(b), the particle number density, Fig. 3(c), as well as the yield strength, Fig. 3(f).

In a number of studies [3, 4], the laser beam was applied vertically with respect to the surface of the wheel, i.e., at an incident angle of zero.
On the other hand, laser dressing that removes the wheel materials through ablation of the bonding material (resin) to expose cutting grain edges has been tested for aluminum oxide wheels [6,7].
A number of laser processing parameters could thus be predicted.
A large number of CBN particles are connected with vitrified bonds and there is porosity on the wheel surface.

However it suffers from limited ductility at room temperature due to its low crystallographic symmetry and the restricted number of independent sliding systems [4,5].
However, if we wish to simulate a large number of atoms, this technic is no longer suitable (computation time too long and computer resources too large).
Results and Discussions 3.1 Twin interface energies The formation energies of the four twins are calculated according to Equation (1) [25], where EtwinTi-Ti  and EbulkTi-Ti represent the total energies of the pure Ti supercell containing twin boundary and the bulk Ti respectively (with the same number of atoms in the both configuration) and A (X dimension by Y dimension) represents the area of the twin plane in the constructed supercell.
The factor 2 comes from the presence of two twins grains in the supercell due to periodicity reason.

Coarse aggregate: gravel, size of grain is continuous and between 5 and 25.
Table 3 Mixture ratio and material usage about C55 concrete [ kg/m3 ] Number Water-Binder ratio Cement Fly ash Sand Stone Water water reducer 1 0.32 350 150 (30%) 626.4 1113.6 160 4 2 0.32 325 175 (35%) 626.4 1113.6 160 4 3 0.32 300 200 (40%) 626.4 1113.6 160 4 4 0.32 275 225 (45%) 626.4 1113.6 160 4 5 0.32 250 250 (50%) 626.4 1113.6 160 4 Note: The fly ash how to replace the cement equivalently were shown in brackets Experimental methods and procedures In the light of the requirements of frost resistance performance of concrete in the railway engineering and “supplemental standard on the rail concrete engineering construction quality acceptance” Rail Construction [2005] No. 160, the age of concrete test blocks was 56 days in the test.
Simultaneously, the weight loss rate also increased with the increase in fly ash content under the condition of equal number of freeze-thaw cycles.
Through the above three effects, the microscopic performances of concrete micro-pore structure were better than normal concrete, either the number of pore or the graduation of pore.

The cement is ordinary Portland cement of P32.5, the fineness modulus of natural medium sand is 2.70, the grain composition of basalt cobble is 5mm-10mm, 10mm-20mm, 20mm-40mm.
Table 1 Size and Number of Specimens [mm] Label Size (2W×h×t) Precrack (a) a/h Number A60-1~8 400×300×150 60 0.2 8 B60-1~8 300×300×150 60 0.2 8 C60-1~8 500×300×150 60 0.2 8 D40-1~8 400×200×150 40 0.2 8 E80-1~8 400×400×150 80 0.2 8 Note: In Label of A60-1, A stands for size of 400×300×150, 60 stands for the length of precrack, -1 stands for the serial number in this group.

Each peak was measured using XRD and assigned by comparing them with the peaks in the data provided by the joint committee on powder diffraction standards (PDF numbers: 20-1323 and 33-1387) [15].
Micrographs show tiny grains on the surface of the as-deposited (non-annealed) WO3 thin films (Fig. 2).
The WO3 thin films annealed at 200 oC had a triclinic crystalline structure in comparison with the JCPDS data (PDF number: 20-1323).
The WO3 thin films annealed at 500 oC had a triclinic/hexagonal phase that co-existed with the JCPDS data (PDF numbers: 20-1323 and 33-1387).

The number of crystals on the substrate surface increases with temperature.
This can be conditioned by the activation of greater number of crystal nucleation sites when the heat energy of the system increases.
The thickness of this zinc oxide layer on sample (I) is of 480 nm, the layer surface is rough, and the layer consists of small grains.
The SEM photograph also shows that aggregates discussed in turn consist of a great number of particles only a few nanometers in size.
We suppose that highly grain-oriented polycrystalline and single-crystal zinc oxide film may be provided by fitting parameters of the porous silicon layer.