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Once again, all these diagnosis methods have their own disadvantages, for example, the sample preparation for optical microscopy is very delicate and time consuming and a large number of gel and cracking must be formed for good examination; for SEM-SE, the observation of a fracture surface is not reliable.
The grey level of BSE image is directly proportional to the backscattered coefficient η, which is related to the atomic number Z by the empirical equation [6, 7]: (1) Where a0, a1, a2 are coefficients, which depend on the parameters during image acquisition, such as the accelerating voltage.
Accordingly, the higher the average atomic number, the brighter is in the backscattered image.
Fig. 4 shows the mapping of concrete, presenting the reaction of fine dolomite grain with alkali.
Hydrotalcite has a fibrous structure, which is filled with the original dolomite grain.

In corrosive environment, the passive film is broke down by the slip of grain, and then local cell is formed, where the bare metal face is anode and the passive film is cathode.
Other examples of corroded areas are shown in Figures 5 and 6 those were formed under stress amplitude of 115MPa at number of cycles, N, of 4.9×105, where Figure 5 shows the slice image, and Figure 6 is a three dimensional demonstration of the binarized image.
It suggests that anodic dissolution occurred along axially elongated inclusions or grain boundary.
The increase of corroded area and depth with number of cycles (or with time) could be measured from Figures 6, 8 and 9, and the shape of the corroded area shown in Figure 9 is similar to that observed by Wei and his co-workers [5].
Acknowledgment The authors gratefully acknowledge the approval of the Japan Synchrotron Radiation Research Institute (JASRI) to use beam line (BL19B2) in SPrin-8 (Project number: 2008A1886).

(a)1cycle (b) 2 cycle (c) 3 cycles Fig. 2 – SEM images for the fracture surface of the composites for different cycles As shown in Fig. 2, many grain pull outs and a few porosities are observed on its fracture surface.
In figure 2 one should note evidences of intergranular fracture, which occurred separating crystalline grains that form the cBN particles.
As can be seen in Table 1, increasing the number of cycles results in a higher degree of transformation of α-Si3N4 to β-Si3N4.
Table 1 - Si3N4 composition after sintering process Number of cycles Wβ (%) 1 51.4 2 58.9 3 62,1 After polishing, the mechanical properties of the sintered compacts were tested.
Table 2 - Some properties of the sintered compacts Number of cycles Microhardness (GPa) Relative density(%) Edge Center 1 7.4 10.5 93.1 2 12.9 15.1 95.8 3 13.2 17.5 96.2 Figure 3 shows the results on tests for abrasion carborudun disk.

The spin-coating, drying and heat treatment processes were repeated for times, in which the number of CMN repeating was twice of that of CT doing, as the best molar ratio in CMN/CT bulk material[7].
The number of total repeating times was Fig.1 Schematic structures of multilayers CMN/CT heterostructure thin films 9 to obtain the suitable thickness for testing.
For comparison, the CMN and CT homogeneous thin films, with same number of layers, were prepared in the same process.
The CMN-CT heterostructure thin film surface grain boundaries were not very clear, due to bottom layer CMN film.
It was found that the grain size and root mean square (RMS) roughness of CT film were larger than those of CMN film.

.%) elements C Si Mn P S Cr Mo Ni Cu results 0.26 0.24 0.010 0.0047 0.97 0.42 0.040 0.088 API Spec 5DP[1] [2] - - - ≤0.020 ≤0.015 - - - - SY/T 5561-2008[1] [2] - - - ≤0.020 ≤0.015 - - - - Table 3 Result of metallographic analysis location microstructure Grain size Inclusion type and grade Crack analysis Drill pipe Sorbite（fig.1） 9.0 grade A0.5，B0.5，D0.5 No crack 20μm Fig.3 Microstructure of drill pipe Mechanical Properties Test Tensile samples and longitudinal Charpy V-notched impact samples were cut from failed pipe body.
The intergranular morphology and quite a number of second-cracks are shown in the propagation zone, shown in figure 7.
Table 4 Results of mechanical properties Item number Tensile test results Impact absorbed energy/（20℃） （J） Tensile strenghth （MPa） Yield strength /MPa Elongation （%） Drill pipe 1120 1020 20.0 76 1120 1010 21.5 73 1130 1050 20.0 76 API SPEC 5DP[1] [2] ≥1000 931～1138 ≥11.0 single≥38 average≥43 SY/T 5561-2008[1] [2] ≥1000 931～1138 ≥11.0 single≥38 average≥43 Table 5 Result of hardness Item number Hardness test result（HRC） first quadrant 38.0, 37.0, 37.5 second quadrant 38.0, 38.5, 38.5 Third quadrant 38.5, 38.0, 38.5 forth quadrant 38.0, 39.0, 37.5 Fig.4 Fracture morphology under low magnification Fig.5 Along the crystal morphology of fracture initiation zone Fig.6 Corrosion products EDS analysis results of fracture initiation zone Fig.7 Along the crystal morphology and lots of second crack of fracture propagation zone Fig.8 Corrosion products EDS analysis results on fracture propagation zone Comprehensive analysis Chemical composition
Summary 1) Chemical composition, microstructure and mechanical properties inclusion size and grain size of failed drill pipe meet the requirements of standard SY/T 5561-2008 and API Spec 5DP. 2) Drill pipe fracture belongs to hydrogen sulfide stress corrosion crack.

It consists of a core characterized by dense random packing and a high coordination number of particles and of a shell or boundary characterized by loose random packing and a low coordination number of particles.
A large body of data shows that the grain growth kinetics is described as follows: (31) where L0 is the mean grain size at t = 0; , Q is the activation energy; m is the exponent which depends on the mechanism of mass transfer.
The analysis of the grain growth kinetics during the sintering of chromium carbide [30], as well as our data for grain growth during the annealing of pressure sintered titanium and molybdenum carbides, has shown that m = 4.
In the process of superplastic strain the fine-grained structure of the material is saved.
Lidman, Densification and kinetics of grain growth during the sintering of chromium carbide, J.

The in-plane response of the arch can be described by constitutive laws governing the behaviour of the nailed joints under shear, parallel and perpendicular to grain, and bending moment in the plane of the plank.
The nails respond in the direction perpendicular and parallel to grain with a given stiffness, Kper and Kpar, respectively, dependent on the timber material characteristics and the geometry of the nailed connection.
Self-tapping screws were used instead of the traditional wrought iron nails due to difficulties in getting a sufficient number of original nails similar to each other.
The response of the joints under shear parallel and perpendicular to grain and bending are simulated by means of rigid finite elements, which behave as elastic springs.
For this purpose, different values of nails’ shear stiffness, considering a direction of loading different from perpendicular and parallel to grain, can be considered.

Two grain structures were typically reported in the fusion zone (FZ).
In the middle of the FZ, straight axial columnar grains with a growing direction in welding direction and curved columnar grains growing from the FZ boundary occur [13].
Furthermore, axial grains are susceptible to centreline solidification cracks [15].
The width and height of the axial columnar grains can be reduced by increasing the welding speed [13].
Rao, Grain refinement through arc manipulation techniques in Al-Cu alloy GTA welds, Mater.

On the other hand, the spent AC contains a great number of chlorine compounds.
Table 2 shows, the mechanical strength of the three kinds of activated carbon was similar, which indicating that the regeneration activated carbon could reach the level of strength of fresh activated carbon. 3.7 Grain size distribution of activated carbon Fig.7 Grain size distribution of activated carbon Fig.7 show the grain size distribution of activated carbon was ranged from 0.65mm to 0.85mm, The grain size of spent activated carbon and regeneration activated carbon were relatively large compare with fresh activated carbon, this is because the activated carbon got coking and sintering during repeated use; the grain size of regeneration activated carbon was decreased after activate with steam, this is because the water vapor reacts with carbon, the activated carbon was activated which had been coking and sintering.
Fig.6 indicating that the regeneration activated carbon could reach the level of grain size of fresh activated carbon 3.8 SEM of activated carbon Fig.8(a) (b) (c) (d) were SEM image of the regeneration activated carbon, fresh activated carbon, thermal desorption activated carbon and spent activated carbon.Fig.8 show that after thermal desorption the spent activated carbon, whose channels and pores were block with chlorides has basically been reopened.
Through mechanical strength and grain size analysis, and the reaction performance analysis of regeneration activated carbon, they indicated the spent activated carbon of catalytic synthesis for 3,4,5,6-Tetrachloropyridine-2-carbonitrile can be repeated use after thermal desorption- steam regeneration.

The fungi were cultivated on a plant substrate (woody greens of fir and pine; sawdust of fir, larch, aspen, pine, birch; wheat straw; substandard cereal grain) in Petri dishes under aseptic conditions.
It has been established that the maximum number of bacteria in wastewater is 22 · 105 CFU / ml.
As a result of the research, wheat straw, sawdust (wood chips) birch, larch, pine and substandard wheat grain were the most promising for further study.
The experiment gave reason to exclude the use of expensive substandard wheat grain.
A mycelium-based material for biodegradation of cyanide: A – solid-phase cultivation Fusarium oxysporum on lignocellulosic waste with substandard wheat grain; B – solid-phase cultivation on lignocellulosic waste; C – dry mycelium-based material.