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However, there were a limited number of reports which deal with big current density and stability of the field emission of globe-like diamond microcrystalline aggregate films, which were grown in the high methane concentration (H2/CH4=100/10 SCCM) using a microwave plasma chemical vapor deposition (MPCVD) system in our laboratory.
The peak at 1332.1 cm-1, which is shown in Fig. 2(a), is due to diamond grains Raman scattering and declare that the globe-like microcrystalline diamond aggregates are composed of diamond crystal.
The globe-like diamond microcrystalline aggregates exhibiting good electron field emission would be attributed to possible mechanism of the diamond edge emission [7] and good electron channels from substrate to surface by the grain boundary [8].
The good emission properties of the diamond aggregates are considered to be combined results of diamond grains and the lots of the grain boundaries in the diamonds microcrystalline aggregates.

The average thickness of each layer of Ba0.5Sr0.5TiO3,Ba0.6Sr0.4TiO3, Ba0.7Sr0.3TiO3 and Ba0.8Sr0.2TiO3 filmsis increasing with increasing number of deposition.
During the deposition process, after the solutions are spun, the films are baked and then heated at 500 °C for 30 minutes in oxygen atmosphere which is found is enough to grow the BST grain therefore the next layer coating of BST solution is spread over same films with the established grain boundaries resulted in thicker films.
However, the non-linear increase of films thickness may be caused by the non-uniform grain growth during the deposition of the first layer, so the remaining deposited layers follows suit.
However, the non-linear increase of films thickness may be caused by the non-uniform grain growth during the deposition of the first layer, so the remaining deposited layers follows suit.

The shear-mode cracks grew by local mode II segments (with a small superimposed mode I component) nucleated at spatially distributed microscopic irregularities of the crack front and extended to adjacent grains by forming fibrous patters in the direction nearly parallel to the applied shear stress.
The size of the facets corresponds well to the grain size.
These characteristic crystallographic patterns were observed systematically in all materials with sufficient number of slip systems without barriers for dislocation movement (single-phase bcc and hcp metals) [1].
The intrinsic behaviour in both materials was similar to that of pure titanium and practically does not depend on microstructure in materials with conventional grain size, since the characteristic microstructure parameter is larger than the cyclic plastic zone size around the crack tip.
The intrinsic behaviour in both materials was similar to that of pure titanium and practically does not depend on microstructure in materials with conventional grain size.

Abstract: The XML documents are nested and semi-structured, but the traditional access control mechanism is coarse-grained and not applicable.
Introduction Traditionally, Web servers are primarily intended to provide services for HTML documents, and the access control mechanisms currently available for Web sites tend to be coarse-grained.
Role-based protection eases the task of managing large numbers of users or user groups and/or large numbers of system privileges that might overlap.
In RBACM, all operations are bind to roles, and cannot be reused for authorization, so the overlap of authorization between roles may cause a large number of redundant definitions.
Second the XACM is fine-grained.

It follows from this that the coefficient of friction can be characterized with a number only inside the quasi constant section, i.e. between two definable normal stress values.
Materials and methods The mineral composition, grain morphology and grain size distribution of clays determine the behaviour of clays and clay compounds under the forming process.
For the examination, a yellow clay was chosen with an Atterberg number of 21.5.
Mineral composition of yellow clay Oligoclase Microcline Calcite Dolomite Quartz Muscovite Illite Montmorillonite Kaolin Roentgen amorphous 5.4% 4.4% 1.2% 0.9% 31.1% 15.3% 23.1% 7.9% 4.2% 6.4% The morphology analysis of clay and organic additives by means of a Hitachi TM-1000 tabletop SEM (Fig1., 2., 3.) found that the grains of additives had diverse shapes and a surface complexity with fibrous structure.
The clay consisted of a large amount of flat grains, which might have affected friction.

The FT-IR spectra were recorded on an infrared spectrometer (VERTEX70, Bruker, Germany) with KBr tabletting in the wave number range from 100 to 4000cm-1.
Just as shown in Fig.2(A), under the case of lower molar ratio (1׃3), the resulting appearance of silica is nearly monodispersed and regular spheres with clear interfaces and grain diameter range of 100-300nm.
If the proportion of alcohol rises, or molar ratio being at 3׃3, the product takes the shape of granule with declining roundness, remarkable agglomeration and reduced grain size of 100-150nm.
With the molar ratio of alcohol to water rising (e.g. 3׃3 and 4׃3), the number of alkoxy (RO-) is larger than that of hydroxyl (HO-).
Conclusion The SiO2 nanosized powders with grain size of 100～300nm and specific surface area of 120～300m2/g have been prepared by chlorosilane hydrolysis in alcohol-water mixed solvents.

From the results of his research, based on the distribution of grain tailings, the tailings can generally be used in mixed-layer surface for the sand-sized aggregate replacement.
The number of specimens used in the research can be seen in Table 1.
Sieve analysis testing is intended to determine the composition of grain tailings.
Table 8 : The chemical content of grain tailings (% of weight).
Variations in the number and size of the aggregate and filler in a mixture has caused the changes in the nature of the mixture, which has resulted in conditions of excess or deficiency of asphalt mixtures [6].

It is well known that the addition of B element to low C steels retards the formation of ferrite along austenite grain boundaries by segregating to these boundaries.
However, Nb element was efficient to increasing the toughness of B-bearing steel due to segregating on the boundaries of austenite grain.
The most important factors affecting the mechanical properties of B-bearing steel was the number of precipitate.

Introduction To achieve excellent grain refinement to submicrometer or nanometer sizes, processing through severe plastic deformation (SPD) has attracted much attention over the last two decades [1].
Ultrafine-grain (UFG) or bulk nanostructured materials generally exhibit extraordinary mechanical properties [2].
Processing a material by HPT can produce an average grain size smaller than by ECAP [5].
This confirms the heterogeneity of deformation, even at high numbers of revolutions as shown in Fig. 4.
Vickers microhardness measurements showed lower values at the disc centre at low numbers of turns.

The mass percentage of precipitation production grain size <45μm is increased by 4.3 % under ultrasound intensification with initial αk at 2.0, which is the biggest. 1.
However, because of the periodic attenuating, the grain size, where the mass fraction of particle with size above 44 μm changes from 50% to 90% and attenuating period changes from 3 to 5 months, inherently exists in the Bayer process in China.
It can be seen that, compared with alumina hydrate precipitation without ultrasound treatment, when the initial αk is 1.45, 2.0 and 2.5, the number percentage of <5μm increase by 38.09%, 98.73% and 0.15% respectively, the number percentage of 3~10μm decrease by 25.49%, 76.13% and 0.13% respectively, the number percentage of 10~20μm decrease by 7.54%, 12.82% and 0.02% respectively.
As a result, the micro-crystals attached to the surface of Al(OH)3 crystals break off, and the number of small particles in the liquor increase.
Table 1 Particle size distribution of product with and without ultrasound in different αk αk precipitation condition Number percentage of particle in different size / % <3μm 3~10μm 10~20μm 20~30μm 30~70μm >70μm seed 97.46 2.35 0.14 0.02 0.03 0 1.45 without ultrasound 0.39 73.53 15.01 5.81 4.78 0.48 with ultrasound 39.38 48.04 7.47 2.66 2.22 0.23 2.0 without ultrasound 0.36 76.85 12.93 5.06 4.36 0.44 with ultrasound 99.09 0.72 0.11 0.04 0.04 0 2.5 without ultrasound 97.59 2.23 0.13 0.02 0.03 0 with ultrasound 97.74 2.1 0.11 0.03 0.02 0 3.3 Effect of ultrasound on crystal growth Table 2 shows the effects of initial αk on crystal growth under ultrasound.