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The shift of the representative peak of magnetite towards the higher wave numbers shows a gradual substitution of Fe(III) ions by Cr(III) ones.
The oxide layers formed during 48h oxidation up to 823K and 24h oxidation up to 873K are relatively thin since steel grain boundaries are visible through them.

The large number of experimental works with different results about hydrogen accumulation in zirconium alloys make complicated to predict mechanical properties altering of zirconium parts exploited in hydrogen contain media.
Saturation occurs linearly up to the nucleation and grains growing of the new phase, when it is likely thermodynamically under these experimental conditions.

It can be seen that the section could be divided into three layers: the outermost is oxidation and adhesion layer, the middle is deformation layer in which crystal grains are drawn along the motion direction and form fiber structure, and the inner is the matrix.
Acknowledgements This work was sponsored by the National Natural Science Foundation of China under the number 50405041.

The optimum permeability of a groyne is dependent on various boundary parameters (flow velocities, local turbulence, grain size distribution, etc.) and is strongly interrelated with structural conditions of the groyne field (number and length of groynes, spacing in flow direction).

Diamond crystals exhibit anisotropic characteristics in their elastic behaviors, so the Young’s modulus of the polycrystalline diamond film should be related to grain orientations to a certain extent[6,7].
Generating from combined actions of the Young’s modulus of a large number of orientations, The Young’s modulus in polycrystalline diamond film goes between the minimum and maximum Young’s modulus of single crystal.

Generally in metals, material degradation first appears in the form of dislocation substructures such as veins and persistent slip bands (PSB), and these PSBs accumulate at grain boundaries to produce strain localization, and then finally micro-crack initiate with increasing fatigue cycles.
The displacement potentials that describe the longitudinal and shear waves are written as [12] , (1) where ; ; and , and are wave numbers for the Rayleigh, longitudinal and shear waves, respectively.

The bacterial biotransformation of metalloporphyrins was carried out in 2.0 litre flasks containing 500 ml of mineral medium (pH 7.0) supplemented with 50 g of sterile fine-grained (particle size <1 mm) black shale or synthetic metalloporphyrins (0.05 mM).
Bacterial growth was monitored by plating samples on solid LB medium to determine the number of CFU (colony forming units).

Among the basal plane, screw and edge dislocations, stacking faults, micropipes, inclusions and low angle grain boundaries, the micropipe density is one of the most limiting factors for the production of large area 4H-SiC devices for high power applications, although the density of these hollow core dislocations has been decreased continuously from 100 to 10 cm -2 in commercial wafers.
Therefore a C/Si ratio = 0.9 has been chosen to provide both good surface morphology and a high number of closed micropipes.

Point A, B and C is surface layer, carbon coating and inner SiC crystal grain respectively.
Surface morphology such as degree of roughness, number of defects and surface stress can influence the tensile strength of SiC fibers.

(3)The anti-tensile intensity decrease as the micro-holes numbers increase, but it does not impact practical application.
Effect of Propellant Grain Dimensions on Progressivity,R.