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In order to simulate a conventional slab heating rate, a number of tensile specimens were heated slowly, taking 2h from 1050ºC to 1250ºC and oxidized in air at 1250ºC for 30 min.
For 1100ºC specimens, the number of surface cracks increased with holding time from 5 min to 30 min.
On the other hand, for 1150ºC and 1200ºC specimens, the number of surface cracks decreased with keeping time.
Fe-Cu diagram indicates that the solubility of Cu in austenite is less at 1100ºC (7.5%Cu) than at 1250ºC (10.5%Cu) [7] and a liquid film of Cu (Sn) could be precipitated at prior austenite grain boundaries in this layer and grow on cooling by diffusion of Cu (Sn) atoms into the gain boundaries.
Therefore, Cu atoms in the liquid films at 1200ºC could far more easily diffuse back into steel, decreasing the number of surface cracks with the holding time at 1200ºC.

The airflow field is a two-phase flow of air and sand, it can be described using the Navier-Stokes equation as follows [16,17]: ( ) () () () () () g vupuu t u u t g g g g g v vv vv v v ερτε βε ερ ερ ερ ερ +•∇−−−∇−=•∇+ ∂ ∂ =•∇+ ∂ ∂ 0 (6) where gρ is airflow density, p is pressure, u is the velocity of air phase; v is the velocity of sand particle; τis strain tensor of air phase, β is momentum commutation coefficient between phase, g is the gravitational acceleration, ε is volume fraction of the sand particle, 0 szpε= (7) Fig.1 the district distributing of sandflow field Layer of airflow near land Earth's surface layer Shield layer where z0 is the close-grained degree of bed , the Ps is the probability of jump-start can can be expressed as D u p g s 2 *ρ ∝ , then, Eq.(7) can be rewritten as D u Gz g 2 * 0 ρ ε •
For sand particle i, its influence area is to be obtained at first, then to get the total number of particle in this influence area, and suppose that sand particle i only impact with particles in this influence area.
Let R is a random number, based on the inequality: 1 11 KK R NN − << − − , we can get the ordinal number k of the sand particle that maybe impact with sand particle i in the influence area.
The physical model Sand particle Airflow Calculational parameter diameter: D=1mm density: ρs=2650kg/m -3 instauration coefficient: e=0.80 friction constant: µ=0.12 number: 4000 density: ρg=1.29kg/m-3 kinetic viscosity: µg=1.8·105Ns/m2 beginning velocity of wind: 1.0m/s,3.0m/s smooth length: 1mm time step: ∆ t=10-6s Fig.2 The model of calculation area Boundary Conditions. (1) Fixed boundary: at the fixed boundary of calculating area, one group of virtual particles are used for a strong push force to the particle near the boundary, thus these particles near boundary are protected from penetrating through the boundary.
Besides, the velocity of wind has a great impact on the sand cover phenomenon, and the higher the former, the more serious the latter. 0 500 1000 1500 2000 2500 3000 3500 4000 4500 t =0s t =5. 5s t =11s t =22s time number of sand par t i cl e 0- 2m 2- 3m 3- 7m 7- 8m 8- 9m (a) Beginning velocity of wind is 1.0m/s (b) 0 500 1000 1500 2000 2500 3000 3500 4000 4500 t =0s t =5. 5s t =11s t =22s time number of sand par t i cl e 0- 2m 2- 3m 3- 7m 7- 8m 8- 9m (c) Beginning velocity of wind is 3.0m/s Fig.4 The result of numerical imitates There are also many factors that can cause the highway sand cover disaster, the influence of wind blow has been considered in the research.

A 2k factorial designs have been utilized in the experiment to study the joint effect of parameter factors on output, where k represent the number of factors.
A total number of 20 experimental runs (sixteen factorial points - 24 and four center points) have been listed and carried out using Design Expert software (Version 8.0.6).
This is due to the fact that an increase in the number of abrasive tends to increase the number of impacts per unit area.
A large number of abrasive particles tends to increase the momentum of collision to penetrate targeted workpiece area.
The coarse-grained abrasive particles trim and worn away uncut fiber neatly [8].

This approach allows for the analysis of panels with any number of layers.
The number of layers in one direction is less than in the perpendicular direction.
The greater the number of steps, the more accurate the calculation.
The advantage of using the theory of composite rods is that it can be used to calculate panels with any number of layers.
Möhler, Stress perpendicular to grain», CIB-W18 / 11-6-2 , Proceedings of the international council for research and innovation in building and construction, Working commission W18 – timber structures, Meeting 11, Vienna, Austria, (1979)

The knowledge of these energies can be useful for estimation of atomic distribution in the solid solutions as well as for studies of segregation phenomena at grain boundaries and other crystal lattice defects.
Let us consider the γ-Fe (Fig. 1a): the number of the nearest neighbors per atom Z is equal to 12, the number of atoms in the elementary cell is equal to 4, and the total number of atomic bonds per cell is equal to 24 because the each bond is taken twice into account.
Three Fe atoms are identical, and each of them has 4 nearest Me and 8 nearest Fe neighbors, so that Fe has the following number of bonds: nFe-Me = 4 and nFe-Fe = 8.
The total number of bonds is equal to nMe-Fe+3⋅(nFe-Me+nFe-Fe).
Values of E1(Fe-Fe) and E(Fe-C) are found from the system of equations for the number of bonds: 84E1(Fe-Fe)+108E0(Fe-Fe) + 6E(Fe-C)= Estruct(Fe32C) 24 E1(Fe-Fe)+6 E(Fe-C) = Estruct(Fe4C) (8) The first equation is related with the total bond energy in crystal cell Fe32C taking into account the changed bonding energy for 14 Fe atoms.

Among those approximations is that the initial state be coupled to a large number of final states with similar energies.
For a treatment of systems decaying into small numbers of final states and the attendant failure of the exponential "law", see, for example [5].
Interestingly, in systems like CdS, the hyperbolic delayed luminescence depends strongly on the size of the grains, and in the nematic liquid crystal 4-methoxybenzylidene-49-n-butylaniline (MBBA) it is present in the crystalline form, but disappears on melting [7].
Dividing a single device into many pixels in parallel gives a device with the high gain and gain stability of Geiger mode operation and an output which is proportional to the number of incident photons within whatever counting time is set, provided the number of photons is small compared to the number of pixels.
Dittes, "The decay of quantum systems with a small number of open channels", Phys.

Typical loess seismic landslides in valley city Research has shown that the loess in valley city is the self weight collapse loess and intensity collapse loess which has characteristics as low water content, low density, macropores, low viscous grain content, loose structure, up-growth of joint and the granular space structure.
Among the samples, the number of loess landslides is 53 which accounting for 50.5% of the total number of landslides.
The number of loess-mudstone landslides is 42 which accounting for 40.0%.
The number of loess landslide is 12, loess-mudstone interface landslide is 2 and loess-mudstone landslide is 8.
The number of loess landslide is 11, loess-mudstone interface landslide is 3 and loess-mudstone landslide is 6.

The particle size distribution was calculated in two ways, volume and numbered.
The d50 of particles is 23 y 34 mm for number and volume fraction respectively.
However, the span value [(d90-d10)/d50] is smaller for the volume fraction 0.96 compared to the number fraction 1.4.
Then, relative density is estimated by counting the number of pixels corresponding to the solid phase and divided by the total number of the area estimated.
Guillon, Constrained sintering of BaLa4Ti4O15 thick films: Pore and grain anisotropy, J.

The selected parameters allowed to implement the twisting of the flow of gas (along with the grains of powder) in a counterclockwise direction.
The size and number of pores most significantly depend on the solidification conditions of the melt (Fig. 2, e).
In general, at a fixed cooling rate of the melt, the number of pores in BCM correlates well with the quantitative characteristics of the powder-gas-laser flow used in HPLFT.
By applying different schemes of foundry technology, studied the effect of increasing the cooling rate of the melt on the size and number of pores in the bulk composite material.
Research was supported by Ministry of Education and Science of the Russian Federation, Project identification number RFMEFI57817X0252 and Project №16.4119.2017/PCh.

This was carried out firstly using a mechanical polishing agent with small grain size and then electrolytically.
On the other hand, the shape and the number of primary macro fragments agree with the theoretical predictions for cubic specimens. 3.
Here, the single crystal "compartmentalises" into several volumes which are distinguished by their number of operating slip systems and/or the magnitude of shearing in them.
The theoretically expected and experimentally validated number of fragments formed during the loading process is in agreement for the D1k crystals.
For the D1-single crystal, the number of macro fragments, observed in these investigations, is greater than that theoretically expected.