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But the glue layer cracking failure was not carried on [3].Zhao Xuesong applied ANSYS to simulate bamboo strip surface compression performance, through the comparison between the experimental results and simulation’s, the simulation results are desirable [4] .Ma Jianfeng designed the similar bamboo structure system using bionics principle, and used FEM to verify its performance [5] .V.Laemlaksakul used FEM to study the laminated bamboo chair static and dynamic performance, strength and durability [6] .LU Wei applied ANSYS to study the bamboo parallel grain tensile stress distribution, analyzed bamboo radian effects on stress with emphasis.
The comparison between experimental results and simulation results showed the validity of the model established. [7].To get wood horizontal grain fracture characteristics, Shao Zhuoping used finite element analysis to study the crack tip stress field [8] .Yu Huaqiang applied hot and humid analogy method to analyze bamboo & wood composite material surface and core performance [9] .
Tab.1 Calculation of model parameters number outer diameter（mm） axial length （mm） wall thickness（mm） experiment failure stress（MPa） simulation failure stress（MPa） error 1 90 50 21 10.95 9.625 12% 2 90 60 18 4.7 4.15 11.7% 3 90 55 16 13.58 11.4 16% As shown in table 1, the model created error is less than 16%, the parallel to bamboo culms axis shear model developed above can describe the nature of bamboo culms shear capacity.
:Building mechanical properties of tensile strength parallel to the grain bamboo Test Method.

Moreover, the rare earth element segregates grain boundaries easily, and at the same time, yttrium blocks the diffusion path and enables oxygen diffusion inward the iron.
In previous literatures [6-7], it was reported that the sputtering minicrystal coatings of binary Fe-Y alloys is fine columnar crystal with a large number of grain boundaries and defects such as twin crystal, dislocation, stacking fault etc, which are beneficial to the element diffusion including iron, yttrium and oxygen atoms.
Finally, because of the low solubility of yttrium in iron and the coexisting of both Fe and Y blocks the diffusion of yttrium in the alloys, with the increasing of yttrium content, the short-circuited channel such as grain boundaries and cracks is helpless to resist the diffusion of Fe.

Few studies have been made in typically agricultural producing area or the commodity grain base.
The black soil is fertile and productive because of its parent material, climate, and natural vegetation characteristics[11-12], making the black soil region as the major base for commercial grain production.
The study area has been traditionally associated with agricultural activities, and is the base for commercial grain production.
Table 1 Characteristic value of Cr&Ni in Dehui Black soil Element Mean (mg·kg-1) Minimum (mg·kg-1) Maximum (mg·kg-1) S.D.a C.V.b Sample number Background value[17] (mg·kg-1) Cr 49.85 37.41 82.23 7.51 15.07 110 54.4 Ni 20.85 12.7 31.95 3.16 15.16 110 26 a Standard deviation.

Increasing amounts in the green compacts lead to final foams containing a larger number of cubical cells, a more lacey, open cell structure and larger cell windows, Fig. 2h.
Finally the image quality (IQ) map, Fig. 3d, where the light lines represent grain boundaries with angular misorientations ≥15˚ indicates that the micro-pores, black areas within this micrograph, may be found not only on the grain boundaries but also within the grain interiors.

Aspheric lenses are known for their superior optical characteristics over spherical lenses, which can improve system performance and reduce the number of optical components required.
Table 1 Specifications of the experimental material Lens material Optical glass BK7 Abrasive grain #500(average diameter of 19� m), #800(average diameter of 11.3� m), #1200(average diameter of 7.1� m) [FUJIMI Co.]
Table 2 Lapping conditions which altered the pad connection method Other lapping parameters Pad connection method Load (N) Time (Min) Work rotational speed (RPM) Pad rotational speed (RPM) Pad Abrasive grain type Pad diameter (mm) With sponge 1 7 60 55 IC 1000/ SUBA � #500 14.7 Without sponge 1 7 60 55 MH C14B #500 16 Measurement item Form accuracy ( P-V ) Fig. 1 Connection between the polishing tool and pad using a sponge Fig. 2 Form accuracy under different connection methods between the polishing tool and pad Effect of a pad on form accuracy and surface roughness.
Table 3 Lapping conditions which altered the pad Other lapping parameters Pad type Load (N) Time (Min) Work rotational speed (RPM) Pad rotational speed (RPM) Abrasive grain type Pad connection method Pad diameter (mm) Cast Iron Pad 1 7 60 55 #800 With Sponge 14.7 MH C14B Single Layer Pad 1 7 60 55 #800 With Sponge 14.7 IC 1000/SUBA � Composite Pad 1 7 60 55 #800 With Sponge 14.7 Measurement item Form accuracy ( P-V ) and Surface roughness ( Ra ) Fig. 3 Comparison of the form accuracy after lapping with different kinds of pads Fig. 4 Schematic diagram of the IC 1000/SUBA � composite pad Polishing In the manufacturing process of a lens, a crack layer about 0.5 ~ 2� m will remain after the generation and lapping process, and polishing is the best way to remove it.

There is a possibility to use naturally occurring patterns, like revealed grain structure, but one can face uneven grain size distribution or texture to hampering applicability of DIC technique.
This array was acquired by SEM (using secondary electrons detector in order to obtain clear image of surface relief after microindentation) and processed in custom-written application yielding distribution of hardness.Results The loading itself, the Brinell ball indenter was used for evaluation of material hardness - Brinell hardness number (BHN) of as delivered and annealed materials were calculated from respective indents diameters.
Further refinement of engraved random pattern would enable to investigate influence of individual grain orientation on the plastic flow.

The synthesized B4C crystalline powder consisted of equiaxed particles with a small size (approximately 1 mm), which is less than the size of particles synthesized by the general carbothermal reduction process, because the number of nucleation sites increased with the dispersion of the boron and carbon sources and the grain growth was suppressed under the low-temperature synthesis.
On the other hand, grain growth was observed for the product prepared from the thermally decomposed product obtained using PVA (Fig. 4(c)), even though the synthesis temperature was the same.
The connectivity of the carbon component is conducive to the grain growth of B4C since B4C is formed at the surface of the carbon component by the carbothermal reduction.

In fact, a number of cryogenic structures are constructed with 304L or 316L steels [1].
These precipitates on grain boundaries were the responsible for intergranular fracture because of the reduction of cohesive strength of grain boundaries.
An abundant presence of intergranular precipitates causes the reduction of cohesive strength of grain boundaries [11].

The most serious defect of single crystal blade is the large-angle grain boundary.
Figure 5 is the macro-etching photo of casting, arrows indicate stray grains and pointed lines show the grain boundaries.
Among them, the number of mixed crystal near the center rod is the most, Figure 5 (b) is the component with heat conductor, because of the diminution of supper-cold time and supper-cold region, the trend to generate mixed crystal on the platform reduces obviously, on one side near the wall of insulation heater, there is almost no mixed crystal on the platform. 4.

Samples material and their heat treatment modes Sample number and material Heat Treatment Modes Parameters No. 1.
Steel Hardox 450 Heat treatment by the manufacturer A stationary sample was pressed to the surface with a carborundum abrasive fixed on it, grain size being 100-125 microns with a force of 39.2 N.
Chisels made of steel and cast iron and heat-treated according to experimental conditions were subjected to field trials in the autumn period of deep treatment on chestnut (Calcic Kastanozem) soils of medium grain size in the state of their physical ripeness.
The microstructure of sample No 3 of steel 45, which is most widely used in manufacturing plow chisels, is a relatively homogeneous mixture of ferrite and pearlite grains, characteristic of the normalized state (Fig. 2, b); steel hardness is HB 185 ± 2, 1.