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A number of experiments were carried out in a tubular furnace to investigate the ash corrosion characteristics.
When the temperature was above 550℃, the intergranular attack enhanced, and the more content of carbon in the grain boundaries, the more serious the corrosion is.

A combination of difficulties arising both from the mathematical and the material side restricted the number of available user-friendly models and their applicability to specific alloys or process conditions.
The surface of aluminized samples revealed grain boundaries in relief with respect to the grain interior, as typically found in low-Al activity aluminized parts, where during the process external Al-Ni layer forms and outward diffusion of Ni prevails [10].

By analyzing these microstructure images, eight microstructure parameters including number of pore, total area, classification of area, total perimeter, average diameter, roundness, shape coefficient and anisotropy have been obtained.
On the base of MATLAB image processing library, special corresponding program is written to find the perimeter of pore contour projection ( number of pixels ) , contour lines and the area ( number of pixels ) contained by contour line.
The main characteristic parameters of pore include: the number of pores, pore total area, total pore perimeter, average pore size and pore size grading
Forms of pores between grains are not spherical but different.
Acknowledgment This work was partically supported by the Zhujiang new star project of science and technology(number: 2011J2200018) form Guangzhou science and information technology bureau.

Assembling composite structures requires a significant number of drillings.
Here again, the result of the measurements are impacted to a large extent by the number and orientation of the fibers that are within the stylus evaluation length.
Furthermore, they highlighted a marked disparity in terms of number (or density) and depth of the main pull-outs.
To this end, the Pku criterion seems appropriate since its value is directly related to the extent and the number of the valleys on the profile.
Various geometries of micro-grain tungsten carbide tools were used such as core drills and twist drills.

The experimental results demonstrated that mixed La2O3 and CeO2 have an effect on forming-ability of HA\β-TCP in bioceramic coating and also refined the grain of bioceramic coatings.
Table 1 Composition design of gradient coating Layer number raw placed materials M（weight percent） T（weight percent） 1st coating 30 70 2nd coating 70 30 3rd coating 100 0 Experiment result and discussion The surface of bioceramic coating was researched by XRD and SEM.

With the number of hops increasing, the errorsof average hop distanceare increased.
Assume that the number of simulations is 1000.The nodes are randomly distributed in an area (100m×100m).
N is the number of unknown nodes.
Finally, the WD-DVHOP is simulated separately from the anchor node proportion, the nodes number and the communication radius.
References [1] Savvides.A, Han.C.C and Srivastava M.B:Dynamic fine-grained localization in ad-hoc networks of sensors.In Proceedings of MOBICOM.Forum Vol. 01(2001) [2] NICULESCUD, NATHB: Ad-Hoc positioning system (APS).

Table 1.Data of the (L-5 type)high power electron beam installation Parameter Value/Unit Installed rated power 480kW Rated voltage of 3-phase system,50Hz 380V Accelerating voltage of electron guns 20kV Number and rated power of electron guns 8X60kW Diameter of a ware being sublimated in vacuum £ 1m Thickness of a condensate (0.1-5)10-3m Condensation rate: -for metals up to 50 mm/min -for ceramics up to 5mm/min Number of crucibles -of 1m in diameter 2 -of 0.7m in diameter 2 Length of evaporating ingots 5m Speed of ingot feeding (0.28-280)10-3m/min Maximum tow weight to hold the good in position and to rotate it by mechanism 100kg Level of technical vacuum (6x10-3-10-2)Pa Pressure of cooling water (3-4)105 Pa Consumption of cooling water 12m3/h Total weight ~20 t Occupied equipment area 80m2 Dimensions of mandrels of the bottom mechanisms enable location of heavy bars of overall length up to about 8m of selected
However, for the layers enriched with copper an isotropic structure made of degradated multi polar grains (Fig. 3a) or of modular molecules situated inside copper based matrix (Fig. 3b) is dominated.
Chemical micro-etching along the cross section of the condensate (perpendicular to the surface) revealed, that at smaller amount of molybdenum (material MDK-1 see Table2) metal of higher melting point occurs as separate grains of a medium diameter less than 1mm and/or as well as mixture inside the copper based matrix.
Typical structure of the condensate (Cu-Zr-Y-W) component for the increased content of tungsten (from 40% up to 60% in mass) The columns, of the diameter less than 100mm, also indicate metal-matrix structure however, with the tungsten grains below 1mm.
It is increased with amount of chromium and depends on number, as external as well as inherent stress centre (like cracks on the sample surface, defects at interface due to impurities etc).

In the central part and face of the alloyed layers, the regular grains and intermetallic phases were observed.
The average grain size of the layer was in the range from 100-250um.
The average grain size of the AlMg5 alloy was from 400 to 1000um.
With increased powder amount introduced, an increase in the number of precipitates was observed.
The number of grooves parallel to the sliding direction is evident on all the worn analysed surfaces and ceramic counter-specimens (Fig. 8).

.), the deformation of alloys at elevated temperatures results from long-range atomic-diffusion and/or dislocation movements that can be non-conservative inside the grains.
A more effective way, particularly for casting alloys for applications at relatively high service temperatures and/or under relatively low loads, is to reduce or eliminate grain boundaries as in Ni-based superalloy castings used in the hot-sections of gas-turbine aero-engines.
For agehardenable alloys, second phases function as the major obstacles to dislocations and hence serve as the primary strengthening mechanism among other microstructural features (including point defects, short-range-order, dislocations and grain structure).
Therefore, the second option, i.e. the development of an increase in the number of nucleation sites for the desired omega phase has been examined.
In terms of laboratory detection of atomic clusters or SRO, there are a number of techniques in addition to 3D-AP, but clusters are usually in nanometer size and sometimes SRO is too weak to detect.

This causes a decrease in the number of natural resources available for concrete purposes and damages the environment.
A total number of 78 cylindrical samples were fabricated for the compressive strength test and 39 cylindrical specimens for the splitting tensile strength test, and 26 cylindrical specimens for the HCP test as shown in Table 4.
Batch ID Sea sand FA Sand treatment Number of samples Compressive and split tensile strength HCP FA0PP0 0% 0% washed 9 2 FA0PP10TC 10% 0% unwashed 9 2 FA0PP20TC 20% 0% unwashed 9 2 FA0PP30TC 30% 0% unwashed 9 2 FA0PP40TC 40% 0% unwashed 9 2 FA0PP10 10% 0% washed 9 2 FA0PP20 20% 0% washed 9 2 FA0PP30 30% 0% washed 9 2 FA0PP40 40% 0% washed 9 2 FA20PP20 20% 20% washed 9 2 FA20PP30 20% 30% washed 9 2 FA30PP20 30% 20% washed 9 2 FA30PP30 30% 30% washed 9 2 Testing Methods.
This is because the diameter of the fly ash grains is finer/smaller than the diameter of the cement grains.
So, the small effect of these fly ash grains is to fill the smaller pores in the concrete.