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Meanwhile, the grains of alloy are refined and round.
As can be seen from Fig.2 (a), with no rare earth Ce addition, the grains of Al-4.5Cu alloy are coarse with well-developed dendrite and the grain boundaries are blurred.
While its dendrite trend have been markedly inhibited when adding rare earth Ce, a larger number of primary α-Al phase appears, the grains are small, round, and evenly distributed.
These grains show mostly granular and rose-like shapes without well-developed dendrite.
Constitutional supercooling then causes the grain appear necking-down and free, which also refines the grain.

Internal stresses will result if there is a differential thermal contraction between different phases or grains.
Furthermore, it is possible that internal stresses are generated between grains of different orientation.
The highest stresses will occur at grain boundaries.
These are ready sources of dislocations and the mismatch will be accommodated by dislocation emission or grain boundary sliding.
It has been argued that there are a number of contributions to the mechanical deformation of the precipitates and the polycrystalline matrix during CT that will lead to considerable plastic deformation and high dislocation densities.

The X- ray diffraction pattern shows that TiO2 nanocrystalline thin films are of anatase structure and the grain size is found to be in the range of 20-35 nm.
In sol-gel method more precise control of film thickness, particle size and porosity is achieved by adjusting one or more parameters, like sol concentration, number of dippings, removal rate of the substrate, annealing temperature etc., In the present study sol-gel dip coating method has been used for the preparation of TiO2 thin films using titanium isopropoxide as precursor.
Grain size is found to increase with heat treatment temperature.
The image indicates granular morphology and it is found that as annealing temperature increases the roughness increases and the grain size is found to increase.
The grain size is found to be in the range of 20-35 nm.

Based on previous report, the huge grains observed in CCTO pellets which contain CuO is possibly related to the formation of the liquid phase that wets the grain during sintering process [15].
As a result, the higher excess of La-doped CCTO sample with 5 mole % produced a denser grain structure with normal grain growth ~ 0.5-3 μm.
SEM micrographs show that undoped CCTO promotes abnormal grain growth with grain size about 50 to 100 μm.
However, at higher dopant concentration (5 mole % of La) presents a normal grain growth which produced finer grain size (about 0.5 to 3 μm).
Acknowledgement This project was supported by Science Fund, Ministry of Science, Technology and Innovation (MOSTI), Malaysia under project number 03-01-05-SF0432 and partially by USM Postgraduate Research Grant.

The chemical, grain and mineralogical analyses of the material after mechanical grinding allowed us to define it as an aggregate for concrete in order to give it heat-resistant properties.
The use of aluminum powder in the technology of heat-resistant concrete has a number of drawbacks, the main among which is its strong dusting in the process of mixing with other components of the material.
Waste conversion technologies used by abrasive enterprises allow for extraction of electrocorundum materials by 70 %, the return of reclaimed product in the manufacture of abrasive tools is not always justified due to not matching of the grain characteristics to the regulatory requirements.
The grain composition of the crushed material DATCB and its mineralogy Size of screen opening, [mm] Partial/full residuals, [%] Grain mineralogy 1.25 9.8/9.8 100% clusters of white grains of electrocorundum and bond, hardly could be destroyed 0.63 24.6/34.4 99% clusters of white grains of electrocorundum and bond, hardly could be destroyed 0.315 39.6/74.0 98 % aggregates of 2 –4 grains of white electrocorundum glued by ceramic bond 0.16 15.2/89.1 98 % separate grains of white electrocorundum, grains are hard, couldn't be crushed, matte grain of bond could be split less than 0.16 8.9/98.0 100% grains of white electrocorundum, grains are hard, couldn't be crushed Fineness modulus is 2.1 Preliminary use of the obtained DATCB material in the traditional formulations of cement concrete with the replacement of 50 % quartz to DATCB let us to obtain a composition with a tensile strength 2.5 times higher than conventional cement composition of concrete, and thermal resistance (water, 8000C)
Research of the object – raw materials for construction composition begins with the receipt of characteristics of grain, mineralogical and chemical analyses.

When sintering at 1150℃, 30minite, powder particles bind together and become grains.
Results show that wall thickness 0.15~0.20mm, cell number (1/in2) 330~365, clear cross section (%) 73~79, specific surface Sv(sq m/cu dm）2.52~2.68; specific heat capacity Cp(J/g.K) 0.6~0.7, heat conductivity κ(W/m.K) 10~12; transverse compression strength 40~50 Mpa, longitudinal compression strength 140~150 Mpa.
Before sintering After sintering 10mm Fig.1 The structure of extruded and sintered honeycombs Table.2 Structure parameters of sintered metal honeycombs Material Cell Size （mm） Wall thickness （mm） Cell number （1/in2) Clear cross section （%） Specific surface （sq m/cu dm） 304L honeycombs 1.2 0.15~0.20 330~365 73~79 2.52~2.68 Structure parameters of sintered samples The structure parameters of and physical properties of sintered honeycombs were obtained by measuring and calculating, as showed in Table 2 and Table 3.
It is obvious that raw powder particles bind together to be grains，and the roughness of sintered surface is very high.
When sintering at 1150℃ ,30minite, grains bind together closely，and surface of sintered honeycombs is very rough.

Samples were polished using SiC paper number 320 and subsequently numbers 800 and 1200.
Fig. 6b shows the reconstructed grain boundary planes.
The white dotted lines indicated where the grain boundary planes intersected the oxides layer.
The diffusion of Mn and Cr through grain boundaries was shown to be preferential (Fig. 5).
The samples showed oxide ridges forming at locations where metal-grain boundaries intersected the surface, suggesting that the metal grain boundaries act as preferential diffusion paths for Cr and Mn.

Total mole Initial number of mole Reacted number of mole Final number of mole at equilibrium Mole fraction For example, at 900 ºC in argon with 20% of water vapour, by using [32] cal (3.8) it can be obtained that and [34].
The backscattered electron yield obtained from the interaction between incident electron and material strongly depends on atomic number when the atomic number is less than 40.
The presence of nickel (Ni) element in austenite phase leads to a lighter zone at austenitic grain because the atomic number of nickel is higher than iron and chromium.
Whole surface Austenitic grain Ferritic grain Whole surface Austenitic grain Ferritic grain Fig. 3.34.
Austenitic grain Ferritic grain Ferritic grain Austenitic grain JPH (a.u.)

Deng’s research shows collaborative decision-making model can increase up to 27% of the total profits [2].Majority of existing studies on collaborative decision of pricing and production focus on coarse-grained  production plan.
Literature [3] studied coordination problem between order pricing and fine-grained orders scheduling, and got a better optimization decision than coarse-grained decision, but the authors did not consider supply chain environment constituted by manufacturer and retailer, and simultaneously pricing of multiple orders in practice operation is relatively rare.
Research of this paper is different from existing production decision problem of pricing and coarse-grained and fine-grained production scheduling, and the goal is to solve the collaborative problem between pricing decision and fine-grained production scheduling under cogeneration supply chain environment constituted by manufacturers and retailers.
Continuous price function is constrained by continuous function constituted by a minimum and maximum price interval, in the model as a continuous variable, and discrete prices take values to ​​form price list, price is changed with demand as ladder-type, so sell price can only choose from a number of discrete price list​​, and as an integer variable in the model.
To evaluate advantages of fine-grained production decision with traditional coarse-grained product planning decisions.Without considering production process, only considering product demand and production capacity of each cycle, fine-grained production capacity is aggregated to coarse-grained ability, to build product’s output proportional constraint demand constraints and capacity constraints between products and byproducts.

The small average crack propagation rate in this stage results from the fact that cracks are arrested in front of grain or phase boundaries during a period (number of cycles) required to localize plastic deformation and to initiate a new crack due to the action of the applied stress amplified through stress concentration at the crack front.
In most cases, the resistance of microstructural barriers in polycrystals, expressed through the number of cycles during which a crack remains arrested in front of an interface, is explained through the misorientation between adjacent grains.
Secondly, in a two phase materials, the numbers of cycles required to initiate a short crack in individual phases are not the same for a give applied strain or stress amplitude.
(3) where γp is the dissipated energy to generate plastic deformation inside an Al grain, γAl - the surface energy of Al and D - the Al grain diameter.
Another consequence of Eq. 11-12 is that among two alloys with the same average grain size, the fatigue life is likely to decrease when the grain size scatter increases.