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Results and discussion Hot deformation flow curves.A number of stress- strain curves obtained from the hot compression at different temperatures and strain rates are shown in Fig.1.
This is because at low temperatures, the number of slip systems is restricted, and the processes of recovery softening are not possible.
The DRX critical strain εc and critical stress σc could, in principle, be determined metallographically from observations of the grain structure of quenched specimens.
This technique, although the most reliable in general, is rendered more difficult by the presence of a phase change, and also requires the quenching of a considerable number of specimens deformed to strains both above and below εc.
This is because lower strain rates provide longer time for energy accumulation and higher temperatures result in higher mobility at boundaries for the nucleation and growth of dynamic recrystallized grains and dislocation annihilation, and thus reduce the critical stress level.

The relationship is described by the Bragg equation: nλ=2dsinΘ, where n is a positive integral number, λ is the wavelength of the neutrons, d is the crystal lattice constant and Θ is the angle of incidence and reflection.
If slow neutrons scatter on a magnetized ferromagnetic material, the number of neutrons with spins parallel to the magnetic field and with spins that are not parallel is different.
The mozaicity is defined by the quantity of low angle grain boundaries as well as by the angle that they enclose.
All of the samples were single crystals, grain boundaries were not found. 7.2 Neutron diffraction investigations Neutron diffraction investigations were carried out in order to characterize the quality of the crystals on regarding their mozaicity.
A typical image obtained in such a way can be seen in Fig. 4.a., where the number of neutrons arraving at a given point is characterized by the gray scale value at this point.

As we know, the number of possible Nb starting material is quite limited.
For the preparation of BCN18 compounds, the number of possible Nb starting materials is quit limited.
From Fig. 2, it can be seen that the grain particles are about 40-50 nm.
The particle size was calculated from the Scherrer formula [15]: D = kλ / (B cosθ) (2) where D is the particle size; k a fixed number of 0.9; λ the X-ray wavelength; θ the Bragg's angle in degrees and B is the full width at half maximum of peak.
Increase in sintering temperature led to significant increase in particle size due to grain growth by surface diffusion.

Coarse aggregate: grain size :5-30mm gravel continuous grain.
Table 1 Experiment Mix Number Design strength Water-cement ratio Cement Water Sand Stone Superplasticizer Corrosion inhibitor/ % kg/m3 1 C30 0.49 370 180 718 1077 3 0 2 C30 0.49 370 180 718 1077 3 0.25 3 C30 0.49 370 180 718 1077 3 0.5 4 C30 0.49 370 180 718 1077 3 0.75 5 C30 0.49 370 180 718 1077 3 1 6 C30 0.49 370 180 718 1077 3 1.25 1 C40 0.40 420 168 630 1140 3.5 0 2 C40 0.40 420 168 630 1140 3.5 0.25 3 C40 0.40 420 168 630 1140 3.5 0.5 4 C40 0.40 420 168 630 1140 3.5 0.75 5 C40 0.40 420 168 630 1140 3.5 1 6 C40 0.40 420 168 630 1140 3.5 1.25 1 C50 0.33 485 160 630 1120 4 0 2 C50 0.33 485 160 630 1120 4 0.25 3 C50 0.33 485 160 630 1120 4 0.5 4 C50 0.33 485 160 630 1120 4 0.75 5 C50 0.33 485 160 630 1120 4 1 6 C50 0.33 485 160 630 1120 4 1.25 Note: Corrosion inhibitor percentage is the percentage of per cubic meter of concrete quality.
ICORR is the open-circuit potential for the system. ßa and ßc are the Tafel proportionality constants for the anodic (oxidation) and cathodic (reduction) reactions and are defined as positive numbers.
In this experiment, through calculating, EW is 75.9g, A is 6.52 cm2,d is 7.85g/ml, C is 1.287 x 105 Experimental results and analysis Experimental results Table 2 Experimental results Number Design strength Corrosion inhibitor / % 28d Compressive strength （MPa） Slump (mm) Air content % 60d Corrosion rate (Mpy) 90d Corrosion rate (Mpy) 1 C30 0 31.4 167 4.6 8.11 8.92 2 C30 0.25 32.4 167 4.6 7.45 8.32 3 C30 0.5 34.2 165 4.8 7.37 8.21 4 C30 0.75 38.5 174 4.3 7.23 8.13 5 C30 1 41.6 184 4.1 7.14 8.06 6 C30 1.25 40.2 181 4.7 7.35 8.17 1 C40 0 43.4 163 4.2 7.13 7.97 2 C40 0.25 43.4 163 4.2 6.67 7.68 3 C40 0.5 44.1 189 4.4 6.54 7.52 4 C40 0.75 48.9 177 4.7 6.52 7.37 5 C40 1 47.4 191 4.5 6.36 7.20 6 C40 1.25 44.5 189 4.3 6.58 7.48 1 C50 0 53.2 175 4.2 6.89 7.72 2 C50 0.25 53.2 175 4.2 6.35 7.14 3 C50 0.5 56.9 188 4.7 6.33 7.02 4 C50 0.75 58.4 174 4.4 6.22 6.89 5 C50 1 57.3 178 4.8 6.04 6.78 6 C50 1.25 55.8 185 4.5 6.26 6.93 Note: The corrosion rate expressed in milli-inches

Since hot-pressed method can reduce the number of micro-pores results in increasing crack propagation resisting force by affording more effective load-bearing area, so the breaking strain has been raised for a wide range.
Stress-strain curve at high temperature Table.1 Tensile results at different temperature Fig.5 shows that as temperature rises, size and number of dimples increase gradually.
Furthermore, snake sliding and deflection along the grain boundary can be seen from the upper right in Fig.5-b.
Since materials are composed of polycrystalline, crystal grains with different orientations will restrict each other and it is inevitable that slipping proceeds along multiple slip system at high temperature, and finally reflects on snake sliding trait by intersection of slipping system.
When it was 750℃, number of dimples increased abruptly and dimples spread all over the fracture surface.

It is reported that the impact toughness can be improved by grain refinement, enhanced cleanliness of the steel, refinement and spheroidization of inclusions, and formation of intragranular ferrite on inclusions, ect.
Titanium and calcium have been added for grain refinement in steels and for improving strength and toughness of steels welds [5,7,8,9].
The numbers of small inclusions is the most in 0.01%Ti-0.01%Mg addition steel.
The impact fracture consists of small cleavage planes and a number of dimples can be found in some regions.
Only the characters (such as total number, average diameter, dimension distribution, ect.) of inclusions are suitable, can the inclusions play a role in pinning of austenite growing and promoting of intergranular ferrite (IGF) [10].

During the process of super-speed grinding, abrasive grain will gradually lose cutting ability; if the grinding process continues, that leads to the greater friction between grinding wheel and work-piece and lower surface quality of work-piece.
In order to make the work-piece get the required surface roughness, the running surface of wheel needs to be overhauled that make the running surface show new grains and restore grinding wheel cutting ability.
In practical application, the node number of hidden layer has no rules to follow.
A kind of effective method is gradually increasing the number of network model until network model get higher precision and quick convergence speed.
Results showed that correct recognition rate is 90%.If increase the number of learning samples, identification accuracy will be higher.

It predicts that for a given temperature gradient in the melt larger than the value described in Eq. 1, columnar grain growth will occur: (1) where GL－ the temperature gradient in the melt; N0－ the total number of hetero-geneous substrate particles originally available per unit volume; ΔTN － the undercooling at the heterogeneous nucleation temperature; ΔTC － undercooling at the tip that can be expressed by: (2) where V － the columnar dendrite tip velocity; C0 －alloy composition in wt pct; A－constant based on experimental data On the other hand, if the given gradient is lower than the value described in Eq.(3), equiaxed grain growth will occur, i.e.,
The nonfaceted to faceted phase transition can be described by the Jackson factor α [14]: (5) where η is the number of nearest neighbor sites adjacent to an atom in the plane of the interface, v the total number of nearest neighbors of an atom in the crystal, ∆H the latent heat of fusion, and Tm the melting point of the material, k Boltzmann’s constant, ∆Sf entropy of fusion, R the gas constant.

The abrasive grains are embedded in special resin in FA lapping or polishing, and only the abrasive protruding from the pad contact the work-piece to participate in the cutting process.
There are a large number of abrasives contacting the high area of work-piece simultaneously.
During the process of abrasive grain cutting, the micro-surface of the material undergoes plastic flow, and the phenomenon of plastic uplift occurs, and the micro-topography of the surface of the workpiece is changed.
When other parameters (except abrasive particle size) are the same, the number of abrasives protruded from the pad decreases sharply with the abrasive particle size and the cutting depth of abrasives increases, MRR rises.
With the increase of abrasive particle size, the number of abrasive particles per unit area drops, “tool concessions” phenomenon gets more serious.

Then the roughness of the activated carbon increases and the size of graphite crystallite of GAC is also greatly reduced, showing obvious trend of fine grains.
On the one hand, the activated carbon could utilize the iron oxide and manganese oxide to increase the amount of oxygen-containing groups; on the other hand, the acid pretreatment and mixing are used to enhance its fine grains.
It means that the number of carboxyl groups on the surface of the activated carbon is represented by the consumption of sodium bicarbonate; the number of lactone groups is represented by the consumption of sodium bicarbonate and sodium carbonate; the number of phenolic hydroxyl groups is represented by the consumption of sodium carbonate and sodium hydroxide.
The large number of micropores is huge and the consistent luster at many locations reveals that there are no obvious loading substances on the surface of the activated carbon.