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After oxidation at 1273 K, the number of oxide nodules increased with increasing oxidation time, and these nodules for 0.3, 1.8, 7.2 and 18 ks were 20, 120, 250 and 350 µm in diameter, respectively.
The number of nodules increased with increasing oxidation time, and these nodules for 0.3 and 7.2 ks were 75 and 810 µm in diameter, respectively.
After oxidation for 7.2 ks, the oxide grain size became 33 µm in size.
Nodule formation may occur at the alloy grain boundaries and three fold grain boundary intersections at the early stage of oxidation, and then the deve lopment of microcracks within the scale promote it.

Methods of high-speed heating, cathode heating in electrolytes included, has a number of advantages from the point of view of its use for thermal or chemical-thermal process [3,4].
Carbonitriding constantly expanding use is due to a number of this hardening method advantages as compared to others: the lower temperature of saturation process, more high strength properties of parts.
It is seen that after the processing near grain boundaries iron carbides were formed.
It is known that the formation of carbides on the limits of austenite grains has a direct effect on the mechanical properties of steel.
Thus, the microstructure of the modified surface in both cases represents by itself martensite structure and residual austenite. 50 μm 50 μm c 50 μm b a 25 μm 25 μm grain boundary carbide γ- austenite α′- martensite particles nitride α′- martensite Fig.1.

Ahad investigated coarse-grained soil properties by experimental direct shear tests.
The results indicated that the modification of sample gradation has a significant influence on the mechanical properties of coarse-grained soils [3].
Repetition number of the shear test is 9 to reduce the effect of data scatter for the sample is very dry and loose in some condition.
The shear test on quartz sand showed that: a) Measured data for the dry sand is scatter, the repetition number should large than 7.
Numerical and experimental direct shear tests for coarse-grained soils.

Fig.1 The size of tensile specimen Table 2 The tensile results of cold rolling specimen number Thickness before rolling [mm] Thickness after rolling [mm] Reduction[%] r △r A 3.5 0.8 0.771 1.50 0.30 B 3.5 0.9 0.743 1.50 0.40 C 3.5 1.0 0.714 1.85 0.40 D 3.5 1.2 0.657 1.69 0.40 E 3.5 1.5 0.571 1.44 0.43 The experiment results show: in the range of total cold rolling reduction ε, when ε≤70%, r value rise as the cold rolling reduction rate become big.whenε≥70%, r values significantly drop as the total rolling reduction rises.
In deformation stage, orientation {111} // ND formation requires a certain number of slip systems involved in deformation, for body-centered cubic structure metal, the main slip system of which is{110}<111>, {110} include six crystal planes ,distributed in three position (110), (101), (011) as shown in Fig.2, each plane has two slip direction [3].
Based on nucleation orientation theory, previous studies have shown that during deformation, grain nucleation is uniform, but occurs in a particular area.
The deformed grain can be divided into five typical micro-area: the main Four are the deformation zone, microstrip, interface area, the area around the particle.
For body-centered cubic metal, under the condition of all main slip system participate deformation, grains can achieve{111}//ND orientation by rotation.

Recently, a new production method was successfully developed, by which wrought high Si content Al alloy containing Mg with good plasticity and high strength can be manufactured at a low cost without adding any modifier during casting [1].It was shown that after hot extrusion, the microstructure of alloy was homogeneous and fine which comprises Al matrix of equiaxial crystals with an average grain size of < 6μm and dispersing Si particles and other second-phase particles with an average grain size of < 5μm.
It is also clearly seen that a number of Si particles are horizontally aligned in the top and middle of the stir zone.
When doing texture analysis, the orientation data from the grains smaller than 2μm in diameter were filtered.
A number of Si particles were horizontally aligned in the top and middle of the stir zone.

In other hands, the increase of the transformation temperatures that occured with the number of cycles passed to occur at a lower rate.
Confocal Laser Microscopy and SEM Microscopic analysis demonstrated the presence of grains with well defined contours with polygonal morphology, with an equiaxial tendency, with needle aspects, without pores or inclusions, as can be observed in Figures 3(a), 3(b), 4(a) and 4(b).
For samples submitted to DCT, this increase in microhardness values with the increase in the number of cycles is minimized, that is, the rate in which the microhardness increases with the number of cycles is minor.
Furthermore, the longer the soaking time of DCT, the smaller are the increases in alloy´s microhardness with the increase of the cycles number.
Figure 6 shows the residual deflections increase with the number of thermomechanical cycling performed in all samples.

We report here the microfabrication of 10 µm microband array (number of band in an array, N=17) and its application in labelless impedimetric sensing of T-2/HT-2 toxin.
T-2 mycotoxin and its metabolite (HT-2), are target of concern in the biosensing application due to its lethal toxicity and prominent presence in EU grains industry.
Mycotoxins are secondary metabolites produced by molds; their occurence often associated with cereal grains and cereal-based foods [10].
As high as 25% incidence of T-2 toxin in grain corns was reported in EU countries followed by 6% in North and South America [11].
Besides grain corns, T-2/HT-2 toxin also was found in oats, barley and wheat [12].

（3） In the equation, is the mean of particle number in all grids, S2 is the variance of particle numbers in all grids.
(5)Image segmentation: it was hard to avoid grain binding during image processing, so segmentation of image was necessary.
The watershed algorithm could automatically detect the weak edge of binding-grain and effectively segment overlapping particles
Numbered the mesh and excluded empty grid outside image.
Output the number of particles in each grid and calculate the variance of particles number in grid on image.

Most often there are agglomerates of metal or spinel particles rather than separated particles embedded in ceramic grains.
That is why a number of studies have focused on the development of ceramic-metal composites.
Metal particles are surrounded by ceramic grains.
The spinel areas can surround the metal particles or make an oval-shape areas separated by ceramic grains (Fig. 6B).
Agglomerates of metal or spinel grains embedded in a ceramic matrix are the most common feature of a ceramic-metal microstructure.

It is believed that the presence of a narrow precipitate free zone accompanied by an accelerated growth of grain boundary precipitates is responsible for this fracture mode.
Previous authors [3] have reported on the role of Θ’ precipitation in the bulk in promoting grain boundary fracture, due to increased prevalence in multiple slip allowing for greater cooperative deformation across boundaries.
In specimens with a growing crack stopped prior to final failure, cooled to room temperature, and broken in monotonic tension, the same grain boundary failure mode persists, with ductile dimples apparent on the grain boundaries, and no striations observed in the region of monotonic failure.
(2) Where D = diffusivity, z = coordination number, a = inter-atomic distance, n = vibrational frequency of the lattice (taken here as 1013).
Enhanced precipitation kinetics under cyclic strain promote the formation of intergranular precipitates and precipitate free zones, enhancing strain localization at grain boundaries at 175°C and 200°C.