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After carefully adjusting the contrast between dendrite and eutectic regions, selected low magnification grey scale images were converted into a black and white threshold images and the number of white and black pixels were counted and expressed as volume percentages of each phase.
However, stereo imaging revealed that a large number of very fine micropores form in the resolidified specimen as against a small number of large micropores in conventionally processed specimen.
Redistribution of a few large micropores from conventionally processed specimen into large number of fine pores is understandable as the interdendritic structures are rather finer after re-solidification.
Tu, Grain defect formation during directional solidification of nickel base single crystals, Superalloys 1992, TMS Warrendale, PA,(1992) 125-134. 4.

Both data showed that the niobate nanosheets consist of distorted Nb-O polyhedra with a low coordination number.
This solution was filtered using a membrane filter (pore size, 450 nm) to remove a small amount of coarse grains.
The interatomic distance and coordination number for the KNbO3 colloidal solution were estimated to be 0.3380 nm and 3.1, respectively.
These values are lower than those of KNbO3 (mean Nb-Nb distance 0.402 nm and coordination number 6).
The K-edge XAFS (XANES/EXAFS) spectroscopic data showed that the niobate nanosheets consist of distorted Nb-O polyhedra with low a coordination number.

The clusters of grain size along sample surface from the FESEM image increase as the substrate temperature is increase.
ACKNOWLEDGEMENT This work was supported by University Malaya Research Grant (UMRG) under project number RG141-11AFR, Exploration Research Grant Scheme (ERGS) under project number ER012-2011A, Ministry of Higher Education (MOHE) High-Impact Research (HIR) Grant under project number F000006-21001 and by Postgraduate Research Grant (PPP)-Research under project number PG024-2013A.

Ultrasonic location have the capability to be fine-grained and a high degree of resolution because the speed of ultrasound in air is sufficiently slow to allow the time-of-flight of a signal to be accurately measured[3,4,5].
After collecting data, we aimed at the research of ranging accuracy on the position of different angles as well as different number of reference nodes Fig.2 Average range error contrast figure under different Angle Fig. 2 shows the simulation rendering of mean error when the angle between node under test and reference node is different.
However, with the increase of reference nodes number, the calculation amount of algorithm is becoming more and more large.
Along with the increase of the number of reference nodes, positioning system constantly request.
Therefore, the number of the reference nodes which participate in position calculation increases and positioning accuracy is on the rise.

The low thermal conductivity of titanium alloys causes superheating in the HAZ, increases the grain size and produces residual stresses in the HAZ, exerting a negative effect [7].
Fig. 5(a) and (b) show the evolution of cyclic stress amplitude as a function of the number of cycles at different strain amplitudes in the aging and STA conditions, respectively.
(b) (a) Fig. 5 Stress amplitude vs. the number of cycles at different total strain amplitudes in the (a) aging condition, and (b) STA condition.
Fig. 6 Total strain amplitude as a function of the number of cycles to failure in the aging and STA conditions.
Lindley, The effect of grain orientation on fracture morphology during high-cycle fatigue of Ti-6Al-4V, Acta Mater. 57 (2009) 3584-3595

Of special interest is a recent publication dealing with the magnetic exchange bias of more than 1T observed in the grains of titanoheamatite (FeTiO3 bearing Fe2O3) mineral [1].
IH series were studied processing ceramic samples of a large number of compositions to understand their structural, magnetic and electrical properties [13, 21].
The grains are well developed and homogenous.
The process can be cycled infinite number of times and controlled switching can be programmed and predicted precisely.
We have provided a large number of references for the benefit of those who might be interested in studying this fascinating system.

The effects of the speed, feed rate, depth of cut, grain size, number of passes and oil effect on the grinding of mostly mild steels and alloyed steels are studied [7-13].
There are numbers of studies on the grinding results of various materials mostly including carbon steels and alloyed steels, but a very limited work is carried out on plastic moulding steels by Taguchi method [5, 7, and 12].
Depth of cut was found more important, whereas the grinding speed, grain size, cutting fluid concentration and number of passes are insignificants when grinding heat treated AISI 4140 steel [7].

Main Contents of Grinding Process Simulation As a complex physical process, grinding process is subject to a number of input factors and produces a variety of physical and mechanical phenomena.
Suto and Sata [2, 3] by measuring the number of effective abrasive and wear area to get the grinding wheel topography.
Hegeman [6] found the shape of abrasive grains was more closely resemble the shape of ellipsoid rather than spherical by SEM photographs.
The results show that the algorithm using coupled FEM and SPH can simulate the deformation of any material cutting layer, while avoiding a large number of SPH particle calculation of time-consuming.
Klocke given a model for single grain scratching on 1st European Conference on grinding in 2003, shown as in Fig.8.Yu Siyuan, Lin Bin and Han Xuesong [23, 24] studied a single crystal silicon ultra-precision grinding of molecular dynamics computer simulation.

However, the columnar growth of CVD diamond results in a polycrystalline nature and the grain sizes increase with film thickness.
The 1.4cm-1 shift to a higher wave number indicates a compressive residual stress on the PCD specimen, because the Raman band of diamond moves to higher wave number shifts with increasing applied pressure. 400 600 800 1000 1200 1400 1600 1800 2000 2200 0 10000 20000 30000 40000 1333.4 Intensity (a.u.)
It was found that the original pyramidal crystallites diminished, numerous deepening pits overspread from the protuberant faces to the grain boundaries.
The 2.63cm-1 shift to a lower wave number indicated a tensile stress on the diamond. 1597.9cm -1 was characterized as graphite band.

With increasing the fraction of small powders, the number and size of the pores decreased because small powders filled up the pores between large powders.
To investigate the preferred orientation of grains, XRD analyses are carried out and then the results illustrated Fig. 2.
As the fraction of the small powder increased, small powders filled up the pores and then the number and size of the pores decreased and improved the bonding between powders.
However, the increase of the electrical resistivity at above PL:PS=80:20 could be explained that the carrier mobility decreased due to the the random orientation of powders and carrier scattering by grain boundaries.
The thermal conductivity κ is composed of the electronic thermal conductivity κel and phonon thermal conductivity κph: κ = κel + κph κel is related to electrical conductivity σ by the Wiedemann-Franz law: κel = L0σT = L0T / ρ where L0 is the Lorenz number.