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For the sintered pellets, with regards to the density and grain size, sample F exhibited the highest density with comparable small grain size.
The reduction of grain size at T= 1350oC might be due to the deceleration of grain boundary migration and finally slow down the rate of the grain growth [10].
Fig. 2: Grain size distribution of BCZY pellets for samples S1, S2, S3, S4, S5 and S6.
Two-Step Sintering of Ceramics with Constant Grain-Size, II: BaTiO3 and Ni-Cu-Zn Ferrite.
Suppression of grain growth in sub-micrometer alumina via two-step sintering method.

The polycrystalline silicon samples consist of grains with a characteristic size distribution in the range from 50 to 500 µm.
The commonly used range of small crystallites (grains) is 0.01 - 1 µm (unlike multicrystalline silicon with grain size up to some millimeters), but in extreme cases grains can be as small as hundreds of Angstroms and as large as hundreds of micrometers.
The poly-Si crystals had monocrystallite grain dimensions in the range of 50 - 500 µm (Fig. 2).
This indicates an influence of the grain structure on the phonon spectra in the poly-Si samples.
Acknowledgements This work was supported by the European Commission through the ProFIT programme of the Investitionsbank Berlin (grant number 10126728).

Giant negative magnetoresistance (MR) up to 15 % were observed for nano-scaled grains of Ni1-xMnx(0.23The crystal grain size (≈5nm) was obtained by an adequate annealing condition of 630 K, 200hrs.
After these procedures, the samples were annealed to control the grain size of 5nm typical and to control the crystal coherency.
To estimate the grain sizes, we performed XRD study of the samples with an annealing condition of 693K and 100hrs as shown in Fig.2.
(1) Here, kx denotes the electronic wave number, e, the electronic charge, V, the total volume, m*, the effective mass of the carrier, respectively.

A number of laser-MIG hybrid welding experiments were carried out for 4 mm thickness Ti-70 alloy by the single channel single full penetration welding procedure, and obtained the excellent surface formation welding joints with no internal defects.
The weld grain generally uses the solid phase near the fusion line as nucleation points and grows to weld center.
Ti alloy is a kind of fine grain material with large heat capacity, poor heat conductivity, high driving force of grain grow and strong sensitivity of weld thermal cycle, as a result the weld and HAZ grain of Ti alloy has critical growing tendency.
Fig. 4 shows the coarse grain HAZ microstructure and morphology of Ti-70 alloy hybrid joint.
Owing to the long residence time at high temperature of β-phase, the grain of Ti-70 alloy joint HAZ grow seriously and coarse isometric crystals appears.

And it suggested that under the reasonable extend of current steel grade, the increased amount of Si and Mn can steadily widen the proportion of equiaxed grains, lead to the increase in equiaxed grain amount, hence the decrease in equiaxed grain average radius; The increase in Mo content is able to enhance the nucleation amount; Proper decrease in Cr content favors the increase in proportion of equiaxed grains, but little effects on grain’s amount and radius.
MC method can also be named as random sampling method, make use of random number to solve questions, simulate actual process probability on computer, and sum up certain statistic regularity, but its primary usage is on microscopic field.
CAFÉ Numerical Model CAFÉ model typically used in simulating the competitive growth between equiaxed and columnar grains, the formation of fine crystalline, columnar crystalline, and equiaxed crystalline, the phase change from columnar grain to equiaxed grain, and the equiaxed grains appearance in non-isothermal temperature field, etc.
Amount 40958 42598 45938 Grain Average Size [m] 1.391e-03 1.337e-03 1.281e-03 Serial Mn1 Mn2 Mn3 Grain Amount 40800 42598 43974 Grain Average Size [m] 1.346e-03 1.337e-03 1.321e-03 Serial Mo1 Mo2 Mo3 Grain Amount 42028 42598 43332 Grain Average Size [m] 1.349e-03 1.337e-03 1.329e-03 Serial Cr1 Cr2 Cr3 Grain Amount 43008 42598 42620 Grain Average Size [m] 1.337e-03 1.337e-03 1.338e-03 From Table 3, along with the increment of Si, Mn, Cr, Mo content, 22CrMoH liquidus temperature and solidus temperature are decreased, dendrite tip growth kinetics parameter a3 has decreased too.
The simulated microstructure suggested that after optimization the equiaxed grain proportion is increased by double, the length of columnar grain has been shorten substantially, the statustical amounts of grains is increased by 19.96%, and the average equvilent radius of the grain decreased by 9.20%.

However, the number of cracks per unit area increases with increasing Ca addition.
The grey zones along the grain boundaries are the α-Mg phase of the eutectic.
With the quantity of Ca addition increased, a clear decrease of the α-Mg phase of the eutectic along the grain boundaries is seen.
The ductility of Mg-Al alloy is determined by the number of operative sliding systems.
In the meantime, some Ca-contained phase is dispersed along the grain boundary as homogeneous net shape.

In as-cast alloys, the Mg17Al12 eutectic phase was located at along grain boundaries.
In the Mg-9Al-2Sn alloy, Mg17Al12 phase is observed along the grain boundaries.
Most of the grain boundaries show that the proeutectic α is surrounded by the eutectic structures of Mg17Al12 and Mg2Sn [10].
This may be due to the large number of particles and coarsening of Mg17Al12 phase along the grain boundaries [11]. 0.0 0.1 0.2 0.3 0.4 0 50 100 150 200 250 300 350 Stress(MPa) Strain Mg-3Al-2Sn Mg-6Al-2Sn Mg-9Al-2Sn Fig. 5 Stress-strain curves of as-extruded Mg-xAl-Sn alloys.
The improvement of the tensile properties is mainly attributed to the refined grains and the formation of Mg17Al12 phase.

The fine grained Al-0.10Sc alloy exhibited a higher resistance against fatigue crack nucleation despite the lower yield stress in comparison to the coarse grained Al 2519 alloy.
The fine grained Sc-containing Al alloy exhibited a little higher fatigue resistance in comparison to the coarse grained Sc-free Al alloy.
The Sc-free alloy has a large grain size and precipitate free zones (PFZ) along grain boundaries.
Therefore slip lengths of the Sc-containing Al alloy are very short and the number of dislocations piled-up against barriers was reduced effectively.
The fine grained Al-0.10Sc alloy exhibited a little higher fatigue resistance in comparison to the coarse grained Al 2519 alloy.

Refinement using Rietica software (Figure 3.) and Table.1 show that both samples FTV33 and FTV38 have two structures at room temperature rhombohedral (R3c)and (COD number: 2102915) and Pseudo-cubic (P4mm) (COD number: 1507756), These results indicate that BT and KV have dissolved into the BF matrix, with longer calcination time of 4 hours resulted in a slightly larger crystal size of 80 nm ~ 100 nm.
Z*=Z'+jZ'' (1) Z'=Rg1+(ωRgCg)2+Rgb1+(ωRgbCgb)2 (1.1) -Z''=ωRg2Cg1+(ωRgCg)2+ωRgb2Cgb1+(ωRgbCgb)2 (1.2) Focusing on the response of the grain, then the data is represented by a circuit model consisting of a parallel combination of grain resistance (Rg) and grain capacitance (Cg).
Furthermore, the analysis of the grain response was searched by the least square circle fitting method in Matlab to determine the diameter of the semicircle, which then found the value of the grain resistance Rg and the grain capacitance Cg.
The impedance plot shows two semicircles, which confirms the existence of two relaxation processes associated with the grain and grain boundaries.
The decrease in grain conductivity is related to the number of VÖ defects in the FTVx samples with more significant BaTiO3 in FTV38 due to low mobility.

Xi’an ,Shan Xi 710065 aljysrq@163.com,bzlj52208@163.com,cdb1051401313@sina.com Keywords: Highway; fine-grained weak saline soil; compaction characteristic; experimental study; technical problem; vibration-compaction parameter Abstract.
In order to solve the technical problems of fine-grained weak saline soil subgrade compaction, combing with Qarham to Golmud highway project, this paper studied the compaction characteristics of the weak saline soil by experiment, determined the optimal vibration-compaction parameters, and compared with the compaction effect that relevant criterions proposed.
Introduction There are a large number of saline soil in Qarham salt lake and surrounding area, in which chloride and chlorite fine-grained saline soil account for the major.
Table 6 Test results Tent number Water content (%) Vibration time (min) Vibration frequency (Hz) Vibration amplitude (mm) Dry density (g/cm3) NO1 13.5 7 30 0.8 1.726 1.0 1.749 1.2 1.812 1.4 1.846 NO2 14.0 6 30 0.5 1.705 0.7 1.803 0.9 1.835 1.1 1.899 Fig.6 The relationship between vibration amplitude and dry density Analysis of Table 6 and Fig.6 results： Vibration amplitude has a greater impact on the dry density, dry density increases with the amplitude.
Therefore , it is suggested the vibration amplitude ranges from 0.7mm to 1.0mm while compacting the fine-grained weak saline soil (sand-silt).