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Material removal in grinding is performed by abrasive grains, the rake angle is mostly assumed intense negative.
Therefore a single grain dressing diamond at 0.33 ct was used as tool.
The main rake angles on both sides of the grain are down to -45°.
Fig. 5: Modelled Grain Numercial simulations of threedimensional cutting models usually take a long time because of the very high number of required elements in the contact zone.
The grain was modeled as a tool and treated as a rigid body in order to save calculation time.

It is obvious that zirconia, whose grain dimension is about 1μm, distributes evenly on the grain boundaries of alumina whose grain dimension is about 2μm.
The temperature gradient was introduced into the experiment, which constrained the growth of the crystalline grains and reduced the gas cavity effectively.
In the sintering process, how to control the growth of grains and reduce the gas cavity has been the important question need to be solved all the time [7].
Slip casting can effectively control the glomeration of the grains, which improves the homogeneousness of the large-scale alumina matrix structural fine ceramics.
R. of China (subject number 03BS103) and the Department of Science and Technology of Shandong Province (Subject number 032090106).

L. ferrooxidans presented higher amount of cells attached to the grains compared with Acidithiobacillus species.
When Fe 2+ was included to chalcopyrite cultures, it was also observed an increment in the amount of A. thiooxidans cells over the grains.
In mixed cultures it was observed the formation of a dense layer of cells over the grains.
In most of the cases, the addition of Fe 2+ increases the cell numbers.
These species allow growth of this bacterium attached to the grains and in the plaktonic phase.

The thickness of the annual rings and slope of grain were also measured.
Tension force on samples loaded parallel to the grain was increased gradually.
The screws were oriented perpendicular to the grain.
The screws were oriented perpendicular to the grain.
However, due to limited sample number, presented results are prone to statistical error.

The average grain size was measured by the linear intercept method.
The average grain size increase gradually as show in Table 2.
Table 2: Average grain size calculated from FESEM images.
The coercivity Hc decreased gradually while the number of x increased.
However the coercive force decreased gradually while the number of x increased.

For scanning electron microscopy, a number of representative samples were chosen.
In a number of cases, it was apparent that a very narrow scar existed over an extended length of the blend line outside the main lens-shaped scar, in one or both directions.
The SEM analysis of the wear scars showed that they all comprised of grain pull-out with clear facetted sides to the remaining pits.
Fig. 3 Head scar centre region showing grain pull-out Conclusions Out of the sixteen explants examined, eleven showed evidence of wear scars.
The SEM analysis confirms that the initial intense wear process consists of individual grain 'pluck-out' followed later by groups of unsupported grains breaking away.

The XRD pattern of studied samples corresponded to bismuth sodium titanate and bismuth potassium titanate numbers 36-0153 and 36-0339, respectively.
Fig. 3 (a) Bulk density and (b) grain size of (1-x) BNKT-xKN ceramics.
For x<0.04, the average grain size was slightly increased with a maximum of 1.56 mm.
However, the KN content more than or equal 4 mol.% average grain size showed slightly decreasing.
The uniform grain size could be normally observed whereas a few abnormal grain growths were found.

The grain size is small, and a large number of voids exist; Region 2 is arranged in dense columnar grains.
The grain size continues to increase, and the surface of the film is rough.
Region 4 is the transition zone, consisting of a large number of fibrous grains, which is not marked in the diagram.
The ZnO films without heat treatment have low crystallinity, and are often subject to have online defects, stacking faults and grain boundaries.
When the grain orientation of ZnO films is poor, which is prepared by direct current magnetron sputtering, the grain boundary stress causes the ZnO band gap to move in long wavelength direction.

For the middle stage (0.7<α<0.9), the crystallization mechanism is surface crystallization with one dimensional nucleation graining growth at a near-zero nucleation rate.
JMA model is valid in non-isothermal conditions provided that a new crystalline phase grows from a constant number of nuclei and all nucleation is completed before the macroscopic crystal growth started[17].
This anomalous change is probably caused by the formation of some α-Fe grains quickly growing up to almost the final sizes.
In the middle stage(0.7<α<0.9)，it was surface crystallization with one dimensional nucleation and grain growth at a near-zero nucleation rate.
This anomalous change is probably caused by that some α-Fe grains quickly growed up to almost the final sizes.

Afterwards, one specimen 6cm long was taken close to each end of the bending specimen, whenever possible – one to be tested in compression parallel to grain, the other in compression perpendicular to grain.
Although some specimens present a high number of insect tunnels visible on the end grain surface, thus giving the impression of a high destruction level, the corresponding area reduction is not so important due to the small diameter of insect tunnels, as shown in Fig. 4.
Examples of calculation of Fmax and Fy in compression perpendicular to grain Test results and discussion Compression parallel to grain.
Wood – Test methods – Determination of ultimate stress in compression parallel to grain
Determination of shear strength and mechanical properties perpendicular to the grain