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Standard k-ε turbulence model of turbulent kinetic energy equation (3) Standard k-ε turbulence model dissipation rate equation (4) In (3) and (4), k-turbulence kinetic energy; μt is turbulent viscosity, Pa/s; σk, σε is turbulent Schmidt number of the k equation and ε equation; C1ε is turbulent kinetic energy of the shear rate multipliers; C2ε is turbulent kinetic energy dissipation of the multiplier; Cμ is turbulent viscosity correction factor; the C3 is k-ε buoyancy model coefficients; C4 is k-ε buoyancy multiplier; β is coefficient of thermal expansion; σt is empirical parameters; T is Temperature, k; Ф is viscous heat generated items.
(5) Where, Hcmax is vacuum maximum value of the vacuum chamber, kPa; d is suction hole diameter of the seed plate, cm; C is distance between the center of seed gravity and the suction seed plate, cm; m is one seed quality, kg; v is line speed at the center of the suction hole on the row seed plate, m/s; r is turning radius at the suction hole of the row seed plate, m; g is acceleration due to gravity, m/s2; λ is seed frictional resistance combined factor, λ=(6 to 10) tan θ, θ is natural angle of repose of the seed; K1 is coefficient of reliability of the absorption seed, taking 1.8 to 2.0, thousand grain weight of the seed are small and shape spherical, taking a small value; K2 is outsidecondition factor, taking 1.6 to 2.0, it take greater when the seed grain weight is large.
The test used the seed plate with diameter of 180 mm and thickness of 2 mm, according to the literature[14], the suction hole diameter selected 4.2 mm for small grain corn. 1. rack 2.exciter 3. sediment device 4. pulley 5. sandbox 6. triangle bracket 7. seed containers 8. air-suction seed metering device 9. the inverter 10. conveyor belt 11. fan 12. exciter control panel Fig.5 The simulated surface air-suction seed metering test-bed Experimental analysis of rowing performance of different distribution diameter of suction hole.

N is the total number of slip systems.
The hardening is contributed by dislocations at both global and local slip systems levels within a grain.
Lin, et al, Three-dimensional virtual grain structure generation with grain size control, Mech.

After compaction and thermomechanical processing, the alloy is recrystallised to generate a coarse microstructure showing high grain aspect ratio to avoid as much as possible that the creep resistance be impaired by grain boundary sliding or the formation of grain boundary creep pores.
Therefore, an estimate of εc can be obtained directly from only the measurement of height h of a larger number of trajectories.

Mainly because the sand ratio increases to a certain extent, proppant grain distribution is dense, the reunion phenomenon occurred in a fracturing fluid,and fracturing fluid viscosity makes the dense sand particles group act like a big particles, equivalent to greatly increase the particle diameter, causing particle settling velocity increase.This phenomenon is also referred to as "particle reunion" effect. 3.4 correlations for critical sedimentation velocity and particle settling velocity Through the analysis of the above experimental results, considering the influences of sand ratio, temperature and foam quality on proppant settling velocity and critical settling velocity of fracturing fluid, the type(1) and (2) are fitting results to show correlations form calculated the particle settling velocity ut and critical settling velocity Vcr of fracturing fluid, the average error are 12.32% and 13.5% respectively:
The proppant grain density is about 1700 kg·m-3. the type scope of application is: 0≤CS≤10%, 10%≤Г≤85%, 40℃≤T≤80℃, P=10MPa
Conclusion 1)The proppant transport experimental results show that with increase of the temperature, the proppant grain in GRF-CO2 foam fracturing fluid sedimentation rate increases,at the same time, the fracturing fluid critical settling velocity increase, showing the proppant transport performance degradation. 2)Under the condition of foaming, with increase of the foam quality, proppant particle settling velocity reduces, fracturing fluid critical settling velocity reduces, proppant transport performance increases;The change law under not foaming condition is just the opposite.
:“Thermophysical Properties of Fluid Systems” in MIST Chemistry WebBook, NIST Standard Reference DataBase Number 69, Eds.

Over the past decades, a large number of plasticizing additives have been marketed, which have been fundamentally different in chemical composition and have different plasticizing effects.
It can be new (only crushed to the desired grain size) or recycled (reuse of originally new SiC or use of SiC from waste processes such as filter dust or debris from sample crushing) [10, 11].
It is a suspension made from crystalline grains containing nanoparticles, the so-called “seeding technology”.
Ribakov at al.: Using Granite Siftings for Producing Vibro-Pressed Fine-Grained Concrete.

Matsuda et al. [6] have shown that grain boundary diffusion of oxygen dominates the initial oxide growth process for Zirconium alloys.
Many large grains that is larger than 10 um in diameter and obvious cracks on surface can be seen by Laser Scanning Confocal Microscope (LSCM).
The transition area is able to tolerate a large number of sub-stoichiometry oxide phase and disorders through a second-order mechanism.
Furthermore, the crystal grains gradually grow larger because of the high temperature.

The results of plasma nitrocarburizing at 570 °C showed the highest surface hardness, highest wear resistance and lowest coefficient of friction due to the number of phases ε.
The α-Ti phase had equiaxed grain.
The grain structure (spectrum 1) on the surface contains 27.39% titanium atoms, 45.42% nitrogen atoms and 27.19% carbon atoms.
The grain structure at cp titanium surface has a higher nitrogen and carbon content than dark areas and light areas.

Technical requirements to be used as interconnect in SOFC should fulfil a number of specific requirements, i.e. a high oxidation resistance, a high electrical conductivity of the surface oxide scales, gas tightness, and a coefficient of thermal expansion matched to the electrolyte and the electrodes [1,2].
The surfaces of Fe80Cr20-53.33 and 38.51 nm were covered with compact oxide scale consisting of fine grain scales (Fig. 4a and b).
For the as commercial ferritic steels show coarser grain scales with the big nodules and spallation across the surface of specimen (Fig. 4d and f), but for the implanted specimen, it show better in finer nodule.
The scale on the surface specimen Fe80Cr20-53.33 nm indicated fine grained and discontinuous (Fig.5a).

The transparent powder grains were found to become translucent at the phase transition as had previously been observed.[9,10] It is clear that pressure induced changes to the diffraction pattern of walnut GeO2 were observed above 8.99 GPa.
It is worthymetioned that the high pressure behavior of GeO2 bulk materials remains under controversy. [9-11] Itie et al, [11] reported a transition occurred above 6 GPa at which the germanium coordination number increases from four to six by EXAFS.
As the nano-crystalline b-GeO2 sample are of an average grain size of 20nm.
As a result, the high pressure phase transition of b-GeO2 to monoclinic phase may occur on the grain boundary of these nano particles. [18b] but further studies are still needed.

While for pH = 9, the platelet-like grains accumulate with each other to form the symmetrical hexagram-like LFP, with the size of about 25 µm (Fig. 1c, 1d).
The platelet-like structure transforms to porous spindle one with a large number of holes on the surface of LFP sample, as shown in Fig. 2a and Fig. 2b.
When the reaction condition is pH = 9 for 24 h (Fig. 2c, 2d), the LFP sample shows the corn cob-like microstructure with the average length of 3 µm for each grain.
The SEM studies indicate that pH condition and reaction time remarkably influence both the morphologies and grain size of LFP samples.