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Introduction ZnO varistors are electronic ceramic devices made by sintering the mixture of ZnO and a number of other metal oxides, such as Bi2O3 and Pr6O11.
It could be seen that the microstructures of ZPCC-based varistor ceramics are consisted of two phases: ZnO grain and intergranular layer.
The Cr2O3 acted as an inhibitor for ZnO grain growth, and the increase of Cr2O3 content made the samples’ ZnO grain size smaller.
With the same Cr2O3 doping content, the ZnO grain size increased with the increase of sintered temperature.
This may be related to that the decrease of the sintering temperature made the ZnO grain size smaller [1].

indicated in Fig. 3c clearly exhibits the grain structure in the square-shaped frame.
The grains labeled by A and B in the figure were of an alpha-iron phase with different crystallographic orientation.
Oxygen and carbon were hardly detected in EELS taken from the grains A and B, as is shown in Fig. 3d.
Alpha-iron grains were formed only in the free-standing nanorods and frames.
Fig. 5a shows a SEM image of nanorods (numbered from 1 to 10) on an edge of a molybdenum thinned area formed by EBID with various partial pressures of iron carbonyl and ferrocene gases.

In regard to this, Costa proposed amultiscale entropyprocedure to coarse-grained time series obtained from the original time serieswith multiple scales.J.
u1t=xt-PF1t⋮ukt=uk-1t-PFkt（7） The scheme is complete in the sense that the original signal canbe reconstructed according to xt=p=1kPFkt+ukt（8） where uk is the residual term,kis the number of the product function.
Two proceduresof the MSE algorithm are briefly described as follow: (1) To obtain the coarse-grained time series at a scale factor ofτ, the original time seriesis divided into disjointed windowsof length τ, and the data points are averaged inside each window.
In other words, the coarse-grained time series at ascale factor of τ , yτ,can be constructed according to the following equation: yjτ=1τi=j-1τ+1jτxi 1≤j≤Nτ （9） (2) SampEn with unity delay is calculated for each coarse-grained time series and then plotted as the function of the scalefactor τ.That is, MSE(x,τ,m,r)=SampEn(yτ,m,r)（10） Feature extractionmethod based on LMD and MSE LMD is a suitable method to analyze the non-linear and non-stationary signals caused by bearing clearance in reciprocating compressor.
The value range of scale factor τ is [1, 30], and the multiscale entropy of each coarse grained time series yτwas calculated with m = 2 and r = 0.15σ, where σ denotes the standard deviation (SD) of the original time series.

The control equations in powder chamber are as follows: 1) Powder grain form functions (1) In Eq. 1, and are ralative burned thickness and relative burned volume of grains respectively.
and are characteristic quantities of grain form. 2) Powder grain burning rate equation (2) In Eq. 2, is average pressure in powder chamber. , and are a half of initial thickness of grains, burn rate coefficient and burn rate exponent respectively. 3) Piston kinetic equation (3) In Eq. 3, , and are mass, velocity and drag coefficient of piston respectively.
The control equations in pump tube are as follows: 1) Continuity equation (6) In Eq. 6, and are density and velocity of helium gas in pump tube respectively, and is cross-sectional area of pump tube. 2) Momentum equation (7) In Eq. 7, is pressure of helium gas in pump tube, and are drag coefficient and pressure loss factor respectively, and are diameter and length of light-gas chamber respectively. 3) Energy equation (8) In Eq. 8, is specific internal energy of helium gas, and Nu are thermal conductivity and Nusselt number of helium respectively, and are helium temperature and wall temperature respectively. 4) State equation of light-gas (9) In Eq. 9, and are specific heat ratio and covolume of helium. 2 Numerical Simulation Results A 30mm/120mm light-gas launcher is taken for numerical simulation using the mathematical model established in the above section.

This method not only overcomes the failure of the traditional phase-comparison method to distinguish different kinds of targets in the same region, but also overcomes the limitation of the image processing method, in which it only classifies the target in a coarse-grained manner.
This method not only overcomes the shortage of traditional method that can not distinguish the different targets, but also overcomes the shortage of image processing method that only give a coarse-grained classifications.
Suppose the antenna sends the signal to location ; the received signals may be regarded as the overlying of echo waves from various virtual layers: (1) where L is the number of layers divided by us, and and are the amplitude and time-delay of echo waves from various layers.
Accurate initial parameters may be obtained by adjusting using the through-transmission technique. 3.2 Determine the number of layers and radar detection parameters according to the depth of target in underground medium The division of layers of the underground medium depends on the two parameters, time range and samples per scan.
In practical measurement, considering the resolution ratio of the radar, we may combine adjacent virtual layers to reduce the number of layers and speed up inversion.

Literature reports clearly indicate PECS is a powerful technique that opens the possibility of processing ceramics with ultrafine or even nanometric grain sizes [2,3].
Grain refinement due to in-situ synthesis largely increases the electrical conductivity but the thermal conductivity however decreases due to an increased amount of grain boundaries.
The addition of carbon in the hot pressed ESK reference grade lowers the grain interface strength, changing the MRM to grain fallout (spalling), which increases the surface roughness.
The roughness in this case is also enhanced by a larger grain size.
Acknowledgements This work was supported by the Research Fund of K.U.Leuven under project GOA/08/007, and the Fund for Scientific Research Flanders under grant numbers G.0305.07 and G.0539.08.

The total production time from liquid steel to hot rolled coil is shortened by increasing number continuous single process steps.
The microstructure development along this process chain is dominated by addressing different mechanisms of grain refinement, as it is e.g. linked to recovery/recrystallization, and also the phase transformation during cooling and reheating.
Example of tensile and microstructure properties for 1.2-mm endless rolled low carbon steel Over the years, a number of combined casting and rolling plants have been built, but the traditional principle remained the same.
The results are convincing that the hot core is helping to end up in a more homogenous austenite grain formation after high reduction mill, before entering the inductive heater (Figure 4).
This process stability does not only apply to temperatures, but also to all other production parameters like strain, strain rates, resulting degree of recrystallized fraction, precipitation and grain growth.

Furthermore, the number and size of this structure increased with the rising of the temperature.
Fine grains particles on the edge of dolomite; g.
Obviously the morphology of the sample containing P whose decomposition reaction has almost completed showing broken because the bubble structure formed before has burst to big empty hole (Fig.4g) when observed by TEM; whereas there appear lots of free and small grains on the boundary of dolomite though there also has holes which is showing formulate (Fig.4h).
The products of thermal decomposition of dolomite containing P shows bubble structure during the reaction, turn bigger as the increasing of temperature and finally burst and escape, which is different from the grains appeared in the process of thermal decomposition of dolomite without P.

A saturation behavior was found by CD for the free vacancy and free SIA concentrations as well as for the number density of the SIAC and the volume fraction of the Cr precipitates for neutron exposures above 0.006 dpa.
The material (average grain size 1 µm, pre-existing dislocation density 5.5´1013 m2) was neutron-irradiated in the Callisto rig (IPS2) in the Belgian reactor (BR2).
The values for the pre-existing dislocation density, r0, and the average grain size, d, are taken from the experiment [1].
A value of about 1.73´1021 m3 is found in the CD simulation for the number density of the SIAC at the experimental neutron doses of 0.6 and 1.5 dpa.
A saturation behavior of the total number density of SIAC in neutron irradiated Fe-12.5at%Cr model alloys for neutron expose in the range from 0.006 dpa to 12 dpa is predicted.

In addition, two-steps compaction process was developed for improving mechanical properties of W-Cu composite as well as segregation of Fe around W grain.
In contrast to one stage compaction, the experimental results showed that the composites fabricated by the two stages of compact ion had better homogeneous structure, high densification and a clear segregation of inter-boundary layer of Fe-W around W grains.
Similar findings were reported by Mohammad et al who also determined the segregation of Fe additive around tungsten grain with added 5wt.% Fe to 40Wt.
Some of the findings of this study are: · The boundary layer segregation of Fe around W grain is marked by two-stage compact process than those composites produced via one-stage compact process
Acknowledgements The authors would like to thank Universiti Sains Malaysia (Incentive Research grant number (1001/227/PBAHAN/8044001) and the University of Omar Al-Mukhtar, Libya for their support in carrying out this work.