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Typical fatigue fracture surface of pre-corroded AA 6A02 coupons are shown in Fig.3, which presents the large number of fatigue cracks (dark grey areas) that have grown around the entire circumference of the fracture surface.
The crack initiation region is a very short fan-shaped area, and most of them became smooth and bright regions due of micro-mechanism of the accumulative plastic slipping of surface grains.
Crack initiation region Crack instantly fracture area Slippage mark Crack steadily Extension area Fig.3 Fatigue fracture morphology in macro-scale Because of the large number of corrosion pits and the effectiveness of these pits as stress concentration sites during fatigue, fatigue crack initiation from these pits is often observed.

Introduction In Turkey, generally, building stock is formed from reinforced concrete (RC) structures and during the latest earthquakes, a large number of these buildings collapsed leading to widespread destruction and loss of life [1].
The concrete aggregates had been used in their natural states without being washed or sieved and that the grain distribution was not suitable good concrete quality.
In addition, many columns had f14 longitudinal reinforcements instead of f16, and the number of longitudinal reinforcements in some columns had been changed.

Where: Mi = (ci, Vi) is characterized by element, Vi is the number of characteristics ci on the magnitude of the field (i = 1,2, ..., n).
Field values with interval numbers：X1=<900,1000>, X2=<85,95>, X3=<85,90>, X4=<170,190>, X5=<80,100>.
[7] Zhang Hong-tao, Mao Han-ping.Four kinds of objective weight determination method of pests in stored grain extension classification application[J]．Transactions of the CSAE, 2009, 25(1):132－136

Introduction The TiO2 is known as an attractive semiconductor material with antibacterial and hydrophilic properties.Both mechanisms were mainly basedon the TiO2photocatalytic ability, which exhibited good performance when TiO2was illuminated with near UV or sun light.A number of researches have proved that the photocatalyticactivities of TiO2 thin films were strongly influenced by their phase composition.
From the Fig. 1 (b), grain size of the crystalline structures was increased with the increased annealing temperature.
As-deposited 300 °C 500 °C (b) (a) Fig. 1 (a) XRD pattern and (b) FE-SEM micrograph of TiO2 thin films at different annealing temperature Fig. 2 (a) Transmission spectraand (b) refractive index of TiO2 thin films at different annealing temperature Anti-bacterial Properties The anti-bacterial effects of as-deposited and annealed TiO2 film coated on BK7 glass against E. coli wereshown in Fig. 3.The results demonstrated slight changein survival of E. coli cells on the as-deposited TiO2thin films before and after the UV light illumination with the UV illumination of 20 minutes, the number of E. coli cells reduced from 2.4 x 108 to 1.8 x 108cfu/ml as shown in Fig. 3(a) and Fig. 3(b), respectively.

Introduction Fragmentation, i.e. breakup into a large number of pieces occurs when a large amount of energy is imparted to a solid within a short time.
Crack formation is captured such that the beams, modeling cohesive forces between grains, can be broken according to a physical breaking rule, which takes into account the stretching and bending of beams , (1) where the two parameters εth and θth controll the relative importance of the two breaking modes.
A large number of simulations were carried out varying the impact velocity v0 in a broad range to cover both the damage and fragmentation phase of the system.

The white layer is a casting layer, and mainly composed of small martensite, a large number of fine residual austenite grains and some carbide.
The molten layer has a higher hardness because of carburization occurrence when a large number of carbon particles generated by kerosene medium penetrate into the molten layer under the action of high discharge temperature.

The grains are slightly stretched in the horizontal direction due to the fact that the material was extruded.
In constant amplitude tests, the specimens (see Fig. 2 left) were loaded to a maximum number of cycles of 2∙106 or until specimen failure.
Constant amplitude tests performed at a stress amplitude of 130 MPa showed no specimen failure, whereas specimens with stresses above this limit exhibited a number of cycles to failure of less than 2∙106 cycles (compare Fig. 4).

Microwave sintering has many advantages, such as rapid heating rate, lower sintering temperature, enhanced densification, smaller average grain size, short processing time, low power requirement and so on[15].
Theoretical calculation and discussion In the γ-LiAlO2: Cr3+ ceramic, the oxygen ions can form tetrahedrons with Cr3+ ions that substitute for Al3+ in tetrahedral centers, and the coordination number of oxygen is four.
Local structural parameters of γ-LiAlO2:Cr3+ (Ref.[19]: ,,,) Ligand numbers 1 2 3 4 Cr-O bond lengths Introducing the average covalent factor model [20-21], we have , , (6) where B and C are the Racah electrostatic parameters and N is the average covalent factor.

The normal weight aggregates used are river sand with a fineness modulus of 2.1.The lightweight aggregates used are EPS beads and expanded perlite with the grain diameter of 2.5mm～4.0mm.
EPS-cement interface transition zone is rich region of the calcium-silicate-hydrate (CSH), there is loose network structure with a large number of defects, as shown in Fig. 3 (b).
Fig.3(c), (d).depict number of polypropylene fibers mixed with concrete across EPS-cement interface transition zone.

Put the shale in the blower drying, then use of ball mill grinding grain size ≤ 0.3mm shale powder alternate.
After considerable analysis, because the sludge contains large amounts of organic matter, when roasting the bricks under high temperature so that the organic matter combustion and left a large number of holes in brick body.
With the content of sludge increase, the number of the holes of the sintering sludge-shale brick is also increase, this situation will reduce the capacity of the material particles bond with each other in the process of the brick body drying and sintering, which brings the increase of contraction and deformation of the brick, thereby greatly affects compressive strength of the brick [4].