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On the other hand, the increase of carrier density and Hall mobility could be attributed to the increase of substituted Ga atoms and the decrease of grain boundary scattering, respectively. [2] Fig.2 (b) shows the optical transmittance of GZO films deposited on PET substrate at various Ptot under constant sputtering power of 50 W and no reactive gas.
The Increased bombardment of high energy particles might increase both defects and internal stress of the growing film. [6] As a result, the films would have poor durability due to the partial detachment and micro cracks of the GZO films fragment during cyclic bending test. 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 (a) 1.0 Pa (b) 2.0 Pa (c) 2.5 Pa (d) 3.0 Pa Ratio of resistance change Number of cycles Number of cycles Number of cycles Number of cycles 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 0 100 200 300 -0.5 0.0 0.5 1.0 1.5 2.0 (a) 1.0 Pa (b) 2.0 Pa (c) 2.5 Pa (d) 3.0 Pa Ratio of resistance change Number of cycles Number of cycles Number
of cycles Number of cycles Fig.3 Change in resistance (∆R/R0) of GZO films deposited on PET at total gas pressure of (a) 1.0Pa, (b) 2.0Pa, (c) 2.5Pa, and (d) 3.0Pa. 1.0 1.5 2.0 2.5 3.0 2 4 6 8 10 12 14 Resistivity 2 4 6 Carrier density 1 2 3 4 Hall mobility Resistivity (x10-2ΩΩΩΩcm) Hall mobility (cm2/Vsec) Carrier density (x1020 cm-3) Total gas pressure (Pa) 1.0 1.5 2.0 2.5 3.0 2 4 6 8 10 12 14 Resistivity 2 4 6 Carrier density 1 2 3 4 Hall mobility Resistivity (x10-2ΩΩΩΩcm) Hall mobility (cm2/Vsec) Carrier density (x1020 cm-3) Total gas pressure (Pa) 200 400 600 800 1000 1200 0 20 40 60 80 100 1.0 Pa : 91.27 % 2.0 Pa : 91.46 % 2.5 Pa : 91.96 % 3.0 Pa : 86.76 % Transmittance (%) Wavelength (nm) 200 400 600 800 1000 1200 0 20 40 60 80 100 1.0 Pa : 91.27 % 2.0 Pa : 91.46 % 2.5 Pa : 91.96 % 3.0 Pa : 86.76 % Transmittance (%) Wavelength (nm) In case of higher Ptot
Moreover, the Ga atoms incorporated in the films might be segregated into grain boundary or formed secondary phase of Ga2O3 [2], which could be related to the decrease of film durability during cyclic bending test.

Fig. 1 illustrates the microstructure image of the INCOLOY 800 using an optical microscopy in which a number of twins were observed in the grain of the INCOLOY 800 including carbide.
As illustrated in Fig. 7 (f) and (g), a large number of dimples were observed in the final fracture region.
It was evident that these ductile fractures were due to the high ductility in the INCOLOY 800. 104 10 5 106 10 7 10 8 0 100 200 300 400 500 600 Maximum stress (MPa) Number of cycles INCOLOY 800 (Plain Fatigue) INCOLOY 800 (Fretting Fatigue) 10 0 101 102 103 104 10 5 10 6 10 7 10 8 400 500 600 700 800 900 1000 1100 1200 Friction force (N) Number of cycles INCOLOY 800(230MPa) INCOLOY 800(200MPa) INCOLOY 800(150MPa) 10 0 10 1 102 10 3 10 4 10 5 10 6 107 10 8 15 20 25 30 35 40 45 Local relative slip amplitude (µm) Number of cycles INCOLOY 800(230MPa) INCOLOY 800(200MPa) INCOLOY 800(150MPa) Fig. 4 The result of plain and fretting fatigue test Fig. 5 Relationship between friction force and number of cycles Fig. 6 Relationship between local relative slip amplitude and number of cycles (e) Higher magnification view of rectangle in
The contact region where the initial crack occurred exhibited cracks that occurred along the grain as shown in section A and illustrated in Fig. 8 (b).

Equal number of specimens for each graphene nanoplatelets content underwent tensile tests.
To form these aluminum carbides, the graphene may react with the aluminum on the grain boundaries [12].
A slight grain refinement occurred from graphene nanoplatelets addition, which is depicted on the slight increase of the dendritic region surface, and led to a consequent increase of the tensile performance.
Considering the slight grain refinement observed, it could be concluded that the pure aluminum has a slightly coarser structure than the nanocomposites [12].
• After 0.1 wt%, further increase of the wt% graphene nanoplatelets content lead to formation of aluminum carbides (Al4C3) at the grain boundaries

The fatigue crack growth rate is defined as the change in crack length (a) to the number of cycles (N).
The size of the grains in the material also plays an important role in the crack growth rate.
The finer the grains, the closer the spacing between grain boundaries which normally increases the yield stress and decreases the roughness of the crack.
A number of the models mentioned have been applied to composite materials with various degrees of success.
Wang, C.H et al. [10,11,12] have conducted a number of studies on the effects of scarf repairs for composite materials.

Results and Discussion When the alternating strain with constant plastic strain amplitude is applied to single- and poly-crystals under investigation the stress amplitude increases and tends to saturate after a number of passes which depends on the crystallographic orientation in single crystals, grain size and thermo-mechanical prehistory in polycrystals.
If the fine structure of deformation bands including intrusions and extrusions is resolved with a help of ECCI, the specific for PSB ladder-like periodic dislocation structure embedded in the vein matrix is evident in the near-grain boundary region, Fig.4.
The number of PSBs increases rapidly until the equilibrium PSB density is produced at saturation when the surface of crystals is covered with clearly visible bands of localized deformation.
Cu polycrystal Number of Cycles, N 0 5000 10000 15000 20000 Stress Amplitude, σa / MPa 10 20 30 40 50 60 70 80 AE Power, P (arb. units) 10 20 30 40 50 60 Internal Friction, Q-1 0.20 0.22 0.24 0.26 0.28 0.30 0.32 0.34 σa Q-1 AE 10μm10μm PSB intrusion and extrusion T.A.T.A. 10μm10μm Grain boundary ladder dislocation structure PSB Fig.4.
The high value of the linear regression coefficient between AE and IF in considerably different materials, variable testing conditions and large number of specimens does not seem to be fortuitous.

Capillary pores form a connected network of mesopores among HP, unhydrated cement grains, fines and aggregate, with an average size from 10 nm to 10 μm.
The fact the cement grains hydrate inwards from the outside means that some cement grains do not hydrate fully and may complete their hydration later.
Cement grains are not the only one capable of hydration.
The data shows a reduction in the number of pores with 0.5 to 0.05 mm in diameter.
Mortar REF/SO4 (without CA) after 28 days + 180 days in a H2SO4. solution, detail of ettringite and a portlandite grain inside the pore Figure 8.

The microstructure was fully recrystallized and presented equiaxed grains with average diameter about 80 µm.
Due to confidentiality reasons, all stresses reported here are dimensionless: they have been normalized by the median fatigue strength at 107 cycles in tension (R=-1), noted σD in the rest of this paper. 10 4 10 5 10 6 10 7 0 0.25 0.5 0.75 1 1.25 f=95 Hz - σmean=0 (R=-1) f=20 Hz - σmean=0 (R=-1) f=50 Hz - σmean=0.81σD f=50 Hz - σmean=0.71σD 1 1 1 1 1 1 1 Number of cycles N Normalized stress amplitude ∆σ/2σD (a) 10 4 10 5 10 6 10 7 0 0.25 0.5 0.75 1 f=50 Hz - τmean=0 - R=-1 1 2 Normalized shear stress Number of cycles N amplitude ∆τ/2σD (b) Fig. 1: S-N curve of tantalum deformed in HCF fatigue, (a) under tension/compression, (b) under symmetric torsion R=-1.
SEM observations of failed specimens enabled to understand this transition in terms of crack initiation mechanisms: intergranular mode appeared for stress amplitudes below 1.2σD, while the fracture was exclusively transgranular for larger stressamplitudes, suggesting that this transition is a consequence of damage being propagated through grain boundaries.
The frequency (fi), time (ti) and number of cycles (ni) of each blocks are summarized in Fig. 5(b), together with the number of cycles at failure upon cycling of the block, extrapolated from the data presented in Fig. 1(a).
Palmgren and Miner proposed that the damage generated by each loading blocks can be added up [5, 6], which results into the numbers of sequences before failure (Nseq) to be expressed by Miner's rule: Nseq = (n1/N1 + n2/N2 + n3/N3) −1 (1) where ni represent the number of cycles in block i and Ni represent the number of cycles at failure issued from extrapolation of the S-N curves under loading i, cf.

Experimental Select nine grains of Myanmar amber samples(MA1-MA9)( Fig. 1)and ten grains of Chinese Fushun amber samples(FA1-FA10)( Fig. 2)to do the research.
Fig. 1 Myanmar amber samples MA1-MA9 Fig. 2 Chinese Fushun amber samples FA1-FA10 Table 1 Macroscopic observation of myanmar amber samples Number Colour Transparency Gloss Fracture Surface observation MA1 redish brown Semi- transparent resinous luster conchoidal thin film on its surface MA2 redish brown Semi- transparent resinous luster conchoidal thin film on its surface MA3 redish brown transparent resinous luster conchoidal bulk white substance on its surface MA4 tawny transparent resinous luster conchoidal much brown substance on its surface MA5 redish brown Semi- transparent resinous luster conchoidal thin film and little white substance on its surface MA6 tawny transparent resinous luster ______ smooth surface MA7 tawny transparent resinous luster ______ smooth surface MA8 tawny transparent resinous luster ______ smooth surface MA9 yellow Semi- transparent resinous luster ______ much brown substance on its surface And then, selected MA8, FA1 and MA3 to analyse the infrared
The resolution of instrument is 4cm-1, the scanning number is 64, the background scanning number is also 64, and the scanning wave number is 4000 cm-1 ~ 400 cm-1.
Table 2 Macroscopic observation of Chinese Fushun amber samples Number Colour Transparency Gloss Fracture Surface observation FA1 redish brown transparent resinous luster conchoidal thin film on its surface FA2 tawny transparent resinous luster conchoidal black coal mine on its smooth surface FA3 tawny transparent resinous luster conchoidal large black coal mine on its surface FA4 tawny transparent resinous luster conchoidal two ends cover with black coal mine FA5 redish brown transparent resinous luster conchoidal two ends cover with black coal mine FA6 redish brown transparent resinous luster conchoidal black coal mine on its smooth surface FA7 redish brown transparent resinous luster conchoidal thin film and black coal mine on its surface FA8 redish brown transparent resinous luster conchoidal thin film on its surface FA9 redish brown transparent resinous luster conchoidal thin film on its surface FA10 redish brown transparent resinous luster conchoidal thin film and black coal mine
on its surface Table 3 Conventional detection of Myanmar amber samples Number Refractive index Brittleness Extinction LW-ultraluminescence Internal characters MA1 1.54 unbreakable ______ royal purple(strong) not easily observed MA2 1.55 unbreakable ______ royal purple(strong) not easily observed MA3 1.54 unbreakable ______ royal purple(strong) dark inclusions, fissure is visible MA4 1.54 unbreakable ______ royal purple(strong) fissure filling with dark material MA5 1.55 unbreakable ______ royal purple(strong) not easily observed MA6 1.54 unbreakable uonspicuous royal purple(strong) relatively clean MA7 1.54 unbreakable uonspicuous royal purple(strong) relatively clean MA8 1.54 unbreakable uonspicuous royal purple(strong) relatively clean MA9 1.55 unbreakable ______ royal purple(strong) white substance Table 4 Conventional detection of Chinese Fushun amber samples Number Refractive index Brittleness Extinction LW-ultraluminescence Internal characters FA1 1.53 fragile anomalous extinction

Chemical compositions of raw materials Chemical composition (mass %) Al2O3 SiO2 K2O Na2O CaO MgO Fe2O3 Tabular Al2O3 99.6 0.03 0.2 0.05 α-Al2O3 powder 99.3 0.20 0.024 0.026 Ultra fine SiO2 0.4 97.5 0.3 0.3 0.2 0.1 0.1 Si powder Grain size ≤ 20 µm, Purity > 98% mixing in a lab mixer for 10 minutes, shaping by an 100t press under 100MPa to 25 × 25 ×125mm specimen., and sintering in electric furnace at 1500°C, 1550°C, 1600°C, 1650°C for 6 hours, respectively.
The matrix composition of samples (mass%) Serial number Micro Al2O3 Ultra fine SiO2 Silicon powder K0 71.43 28.57 0 S3 73.99 23.01 3 S6 76.56 17.44 6 S9 79.13 11.87 9 Table 3.
For Si containing specimens, mullitization and grain growth as well as properties have been changed a lot.
Due to addition of Si powder, mechanism of mullite nucleation turns to following: Si + O2 → SiO(g); SiO + Al2O3 + O2 → A3S2 or Si+O2 + Al2O3 → A3S2 Si melts at 1420°C, wets Al2O3 grains nearby and lowers the temperature where silica forms liquid phase.

The crystalline grain made by electric melting appears good, in needle shape or pillar shape and is easy to break and those made by sintering appears small, generally in grain shape, and is difficult to break.
The band at 3695cm-1 ,3622cm-1, 914cm-1 , corresponds to stretch vibration absorption of -OH, whereas the band at 471cm-1 and 430cm-1 is assigned to intrinsic stretching vibrations of Si-O.show a large decrease of the strongth of peaks.The A1-O binding between the wave number 795cm-1,754 cm-1 was observed to decrease rapidly as grinding progressed .
Nanostructured Materials ,1999,12(1):349 [8]Ghate B B , Hasselman D P H , Spriggs R M.Synthesis and characterization of high purity,fine grained mullite.