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For that reason, a number of additives are currently used in this process, mainly binary carbides such as TiC, TaC, WC or Mo2C.
The rim inhibits grain growth and coalescence of the carbonitride grains during the sintering process.
The ceramic phase has equiaxed grains (F = 0.82±0.06) with an average grain size of titanium carbonitride of 2.4 ± 1.2 µm.
Grain size of the deformed samples has been estimated as d = 2.3±1.2 µm, and the shape factor F = 0.80±0.06, so no grain growth or grain deformation was detected after high temperature creep of the samples.
Grains maintain their size and shape, which is characteristic of a grain boundary sliding (GBS) deformation mechanism.

The grain size distribution curves of sand ejecta were different from drilling soil samples, which explanation need further investigation.
Table 1 lists the numbers of survey points in different intensities.
As shown in Fig.3, the blow numbers of N120 per 10cm were almost uniform to depth about 8m but increases fairly at about 10m.
Fig.6 present grain size distribution curves comparing sand ejecta with the drilling samples.
(4) The grain size distribution curves of sand ejecta and drilling soil samples were quite different.

Powder chemical composition and grain size is presented in table1.
In the case of all materials subjected to research, their hardness increases as the number of strain cycles is increasing, until they reach a maximum around the value of 20000 cycles.
This is because at the inter-grain necks level the concentration factor of stress is greater and there exists the possibility of presence of some micropores, generated by imperfect contact between neighbouring grains. 14 25 12.4 Fig. 3 Specimen for contact fatigue test.
This sensitive is due to the stress concentrator at the inter-grain necks level and of stress state created by Hertzian pressure.
It was noticed appearance of some cracks or pulling off material due to variation at the inter-grain neck level at 70000 cycles.

A number of research institutions in the EU in 2009 launched The Roadmap for the Future Development of Bio-energy (From the inconvenient OF PLANT PHYSIOLOGY AND to clean wood: a European road the map for bio-fuels) [7].
The raw materials from the national reserve in the storehouse for wheat, corn, rice are rotten rice .But after a few years, after finishing digest of rice, the number of the country's "effective grain reserves" is on surface.
Our country population is so much, the grain problem is important, but in recent years the cause of rising food prices is whether caused by biological energy, has not been determined.
In the new biological energy technology haven't realized industrialization, grain as raw materials of biological energy will still be the focus of future development.
Development Report of China's Grain Market ,2008[M] .

A large number of studies have confirmed that hydroxyapatite (HA) has excellent biocompatibility and bioactivity, and it can form HCA mineralized layer when immersed in SBF solution.
The FWHM the diffraction peak indicates that crystallinity and grain size of the samples.
The grain size of C11HA slightly increase to about 200~300nm.
After sintering, the grain size of HA compacts is about 1~2μm.
The existence of a large number of crystal nuclei will limit the subsequent growth of the crystal.

AZ91 magnesium matrix composite is well-organized, and its grain size is significantly smaller than that of the matrix.
AZ91 composite is well-organized, and grain size of AZ91 composite is significantly smaller than that of AZ91 matrix.
The main reason is that alumina silicate short fibers hinder matrix grains to grow up, in the vicinity of the interface of fibers and the matrix, and the grain nucleation location is provided.
In the solidification process, thermal convection of static pressure keeps the growing dendrite broken, and the broken crystal can become non-spontaneous nucleation particles of matrix alloy, accordingly, forming fine grains[9].
On the interface, magnesium reacts with aluminum phosphate binder to generate a certain number of MgO particles and a small number of MgAl2O4 particles, resulting in forming a strong interfacial bonding between alumina silicate fiber and magnesium matrix.

IGC of aluminum alloys is the result of microgalvanic cell action at the grain boundary, related to grain boundary precipitates, which are formed during aging and either more active or more noble than the surrounding solid solution aluminum matrix.
IGC results from microgalvanic cell action at the grain boundary, related to grain boundary precipitates of Mg2Si formed during aging.
In contradiction to the foregoing results of corroded surface, local rather than uniform IGC took place for the three aging states as shown in Fig.3 b, d and f according to the cross section corrosion morphologies, indicating that IGC is very superficial at most grain boundaries.
And the number of pits is much bigger on the underaged surface compared with that on both the peak aged and overaged surfaces.
The surface corrosion morphology revealed that the alloy was susceptible to IGC in the artificial aged conditions, and the IGC resistance decreases with prolonging aging time, resulting from more Mg2Si grain boundary precipitates formed.

Magnesium alloys have a difficulty in fabricating at room temperature owing to its HCP (hexagonal close packed) crystal structure with a limited number of slip systems.
At higher temperature over 673 K a grain size less than 10 � was hard to obtain due to rapid grain growth.
The average grain size measured by a linear intercept method was 91.2 �.
It is noted that the grains are reasonably equiaxed and homogeneously distributed.
This must be understood based on the difference in the grain size.

It is a light-coloured, yellowish sandstone, with psammitic, medium-grained texture.
The grain-size ranges from 0.2 to 0.4 mm, with a few grains attaining 0.5 mm in diameter.
The matrix is very scarce (arenite) and represented by small, angular quartz grains enclosed within aggregates of clay material.
The analysis of the results involves a normalisation process where values corresponding to the number of pixels with a specified intensity are divided by the total number of pixels in a given image (Nv).
Histograms can be used to generate a number of parameters defining the properties of this function, including the maximum histogram value, and the colour intensity that is most frequent in a given image.

The mean grain size for both materials was about 30 µm.
To study the formation and development of slip markings on the specimen surface at very low stress amplitudes and after very high numbers of cycles, the flat specimens were used.
Indeed, the experiments were periodically interrupted after several specified numbers of cycles for surface observations.
In other words, the number of cycles very quickly increases with decreasing the stress amplitude.
Increasing the number of cycles (from 108 to 2´ 108 cycles in Fig. 11) leaded to grow the slip markings [5].