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As the rotation of the body in the process of unloading, the surface has a Reynolds number is Re, (3) u—line speed, ；—perimeter of the revolving body,; V—kinematical viscosity of air.
Body part is a circular pipe still, belonging to the state of natural convection, as the calculation of the convection coefficient: (5) In the formula: d—projectile diameter; Nu—Nusselt number
(6) Gr is Grashof number, the size is: (7) In the formula: g—acceleration of gravity; —expansion coefficient
According to the characteristics of ammunition propellant ignition, generally at higher ambient temperature, the ignition is not due to grain internal heat accumulation, but because of the high local temperature and decomposition reaction, or is directly caused by the local ignition, resulting in the propellant explosion.
The temperature is increased with the increase of speed, the amplitude of temperature rise is not obvious, no risk for grain, safety conclusions rotary unloading process.

To study the microstructure, grain size, and inclusions of the material, the specimens were mechanically prepared and investigated by optical microscopy analysis.
A characteristic value of tensile or compressive strength, fk, is then estimated following EN 1990 [22]: fk = exp(mln f – kn sln f) ≈ exp(mln f – kn Vf), (1) where mln f = ∑i ln(fi) / n (for i = 1..n and number of tests n) and standard deviation slnf corresponds approximately to the coefficient of variation Vf.
The coefficient kn is accounting for probability associated with an estimated fractile (5 % for the characteristic value of a material property) and statistical uncertainty due to a limited number of tests, n.
- When the reliability assessment of a historic metal structure relies on a very low number of destructive tests, it is imperative to: o Verify the homogeneity of the material and make sure that local non-homogeneities and damages (such as geometrical imperfections, caverns, cracks or corrosion effects) do not jeopardise reliability of the structure.
Methods for estimating the average grain size of steel and non-ferrous metals, 1983

Tetrahedral structure of WO4 that appear at wave number of 906 cm-1 and 955 cm-1 in the FTIR spectroscopy confirmed.
Nanoscale Al2O3 exhibits two important features that aiding ionic conductivity in electrolyte such as large specific surface areas and grains covered with various Lewis acidic group [8].
Other bands observed in the wave number specified in Fig. 5 are attributed to W-O and O-W-O vibrations.

A further increasement of Y content causes the grain columns with features of the zone T microstructure of Thornton's model[7] (Fig. 1 (c) and (d)).
The number of Cr deposited on substrates is not changed at a unit time, that is to say, the number of Al deposited on substrates increases.
During the sputtering process, the number of Al deposited on the substrates changed greatly at a unit time with increasing of Y contents in Al targets.
So the number of positive ions to Al targets at a unit time was a constant.
(2) The number of neutral particle increases above Al target containing Y when CrAlTiN layer is produced.

Introduction Air-suction seeder, is able to overcome many shortcomings of mechanical seeding device, has no strict requirements on seed geometric dimensions, easy to achieve single grain sowing, has the advantages of high operating speed and low rate of seed damage.The principle of air-suction in the precision seeder’s design has certain advantages, which is the main study direction of precision seeder [1~3].
The first chain reciprocal screw: The second chain reciprocal screw: The third chain reciprocal screw:, the chain reciprocal screw does not exist. 3.3 Calculation of parallel mechanism’s DOF Come to conclusion by the above calculation results: the number of common constraints λ=0, and the mechanism's order d=6-λ=6, redundant constraints is the constraints in the removal of common constraints, when removing the common constraints, the left t constraints constitute a k-screw, the redundant constraints: V=t-k=3-3=0, there are 0 redundant constraints.
DOF of the parallel mechanism: In which: M—the number of DOF, d—the order of the mechanism (d=6-λ), λ—the number of common constraints, n—the number of components including the rack, g—the number kinematics pair, fi—relative DOF number of the i-th kinematics pair,v is the number of redundant constraints, z is the number of local DOF. 3.4 Motion characteristics of parallel mechanism’s moving platform Parallel mechanism’s moving platform constraint screw matrix as follows: Get moving platform free kinematics screw as follows: Free movement of the moving platform is getting along z-axis, revolving around x-axis parallel and revolving around BC axis, the moving platform has three DOF and can meet the requirements of horizontal adjustment.

Fig. 1 Soft sphere contact model Fig. 2 Simulation device Simulation experiment Dry sand filling process is related to vibration parameters, shape of flask, buried depth and a number of factors, this article mainly uses three dimensional DEM to simulate dry sand filling process, and by investigating the number of dry sand filling direction to study the vibration effecting on dry sand filling movement.
Afterwards count the sand number of the key filling parts for getting the number of dry sand filling curve under the different directions vibration.
Fig. 4 Dry sand filling number curve Fig. 4 stands for the dry sand filling number curve of filling cavity Ⅰ under the different directions vibration, where X, Y, and Z denote respectively flask along the X, Y, Z one-way vibration, XY, XZ, YZ along the X, Y or X, Z or Y and Z directions vibration, XYZ along the X, Y, Z three directions vibration at the same time.
Refer to the 1DOF vibration, filling time is longer, limited fill number is less, which can't achieve full filling.
(3) Compared the three dimensional DEM with the traditional dynamics method, the former fully considers the interaction between the sand grains, greatly improves the accuracy of numerical simulation, which provides a new path and method for further research and perfect EPC method dry sand filling theory.

Simplified Physical Model　 The extruded object between solid particles at the entrance is very poor, in the process of enter the extruder it mixed with grain, it mixed with air in the extruder after entering the extruder will melt in extrusion machine under the action of fluid pressure, thence fluid physical model can be simplified into gas and molten fluid two phase flow model, namely, continuous flow discrete bubbles in the liquid materials [3].
Low Reynolds number method need to have corresponding large number of nodes near wall area and fine grid.
CFX make wall function method and the low Reynolds number method gradually switch between grid, and without accuracy loss.

For example, consider a system of N magnetic grains of size a, uniformly distributed in a nonmagnetic matrix.
According to [1, 4], N1 is the number of particles, whose magnetic moments of both phases are parallel to the external field H; N2 is the number of particles with the magnetic moments of the first phase that are parallel to H and the magnetic moments of the second phase are antiparallel to H.
The corresponding numbers of particles in each of these states we denote as N1, N2, N3 and N4.)

crystallinity caused by the evolution of grain size.
(1) Where P is the circular polarization degree of photons, θ is the glancing angle (50° in this experiment), and nh is the 3d hole occupation number of the specific atom.
As films become thicker and the grain size of film are growing up, the alloy films change from amorphous phase to crystalline phase and the crystallinity becomes better.
According to previous literatures, we should point out that, the 3d hole numbers of ferromagnetic atoms are possibly changeable for different film depth near interface, and play a crucial role in the size of spin moment.
Ryan et al [21] have studied Co/Ge system, and found that the average number of 3d electrons for Co decreases from 7.51 to 6.88 with decreasing thickness.

Non-magnetic and wear resistance is additionally required for a number of applications.
Moreover, their number and ratio should ultimately ensure the presence of all the above-mentioned functional properties of the resulting foundry austenite.
Nitrogen content in these steels is significantly higher than that in a number of grades of nitrogen-containing austenitic casting steels used in Europe and the USA.
The size of the crystallites (grains) of cast steel (in the absence of plastic deformation and recrystallization) is very large, as can be seen from photographs of the macrostructure - Figure. 1.
And after annealing at 1200 °C and quenching, it is not prone to intergranular corrosion due to the absence of particles of excessive phases at grain boundaries and other structural elements of cast metal.