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At present, magnesium metal matrix composite is usually reinforced by fiber or crystal fibre or grains such as graphite, SiC, Al2O3, B4C [2,3].
Because of the existing of detrimental impurities such as the coarse grain of Fe and Ni as well as noncrystal carbon nanograins, carbon nanotubes must be purified before they are added into magnesium melts.
As shown in Fig.6, crystal grains of composite with 0.5% CNTs content is more coarse than those with 1% CNTs content, which displays that CNTs can fine crystal.
On the other hand, a large number of CNTs exist in melt can tamper the growth of crystal and result in fine crystal.
On the other hand, a large number of CNTs exist in melt can tamper the growth of crystal and result in fine crystal.

As we known, the fundamental process of grinding is microscopic cutting with each abrasive grain on the grinding wheel.
Therefore, a number of grinding experiments and simulations with single grit were conducted to support the understanding of the three phases.
Many researchers carried out single-grit orthogonal cutting with a high negative rake angle to investigate the chip formation mechanism and cutting force [6 - 11], where grains were considered as micro-cutting, leading to material removal, and others carried out single-grit scratching [12, 13], where grains were considered as micro-ploughing, leading to elastic and plastic deformation and less material removal.
The free face of collected chips under different grinding speed The periodicity of serrated chip is usually described by the frequency of chip segmentation f, which can be identified with the number of segments formed per unit time [16].
With the increasing of grinding speed, the overall number of grit engagements per second increases, as a result the contact time is decreased, which means the thermal and mechanical effect on contact zone is less.

Quantity, chemical composition, humidity and grain size are common criteria to inspect for raw material.
In the non-improved stage, the material was identified using the batch-number from the supplier, but ambiguities occurred for that cases when the material was delivered on a multi-transportation delivery programme and the actual properties vary in between (even within the same batch).
In the improved stage, the identification of the material is done for each entry using an internal identification number called [Label ID].
Based on the material identification, large spectrum of information is recorded in connection with the inspected material, such as humidity grade, grain size, material integrity and quality documents, all are usually recorded during the inspection by direct examination.
Acknowledgement This work is supported by the Sectoral Operational Programme Human Resources Development (SOP HRD), financed from the European Social Fund and the Romanian Government under the contract number POSDRU/159/1.5/S/137390.

Figure 1 The concentration of zinc acetate solution of zinc oxide particle size As shown in Figure 1, when the Zn2+ ion at lower concentrations than in the system, over saturation in solution is smaller, unit volume produced less number of nuclei, receive deposits grew up easily.
As the Zn2+ ion concentration increases, the supersaturation solution increased, more number of nuclei in unit volume were produced, and sediment particle size decreases[5].
Figure 4 Precipitation reaction time on the impact of nano-ZnO Figure 3 Precipitation reaction temperature on the impact of nano-ZnO Can know from Figure 4 complex reaction time short, grains of foot-path of particle little, distribute the more narrowly.
The response is at the beginning, the solution has very high crossing the degree of saturation, the solution can form a large number of embryos particles in the twinkling of an eye, with extension of time, response of solution in continue.
In the experiments, hope that calcined form of particle shape smooth structured, so that formation of nucleation and grain growth is not too fast, you need to have enough time to make lattice neat and tidy and gradually grew up, sintering and coalescence behavior can also be reduced accordingly[7,8].

The plastic deformation of metal in the specified thermal state will lead to dynamic recovery, dynamic recrystallization and static recrystallization that affect the grain size and distribution of dislocation so as to soften steel.
(4) Where, is the volumetric fraction of phase i and is temperature dependent coefficient of thermal expansion of phase i and n is the number of phases.
（5） Where, is the effect of the austenite grain size, is the effect of alloy composition, is a function of temperature, gives the effect of current fractions.
（6） Where, Qf is the activation energy of ferrite in the diffusion reaction and R is the universal gas constant (8.314 J mol-1K-1), G is the ASTM grain size number for the austenite.
This phenomenon can be explained by the different phase transformation productions and their volume fractions, for the numbers of martensite with high hardness will be produced after water cooling, but a lot of mixture of ferrite and pearlite with low hardness will be precipitated after air cooling.

This is in good agreement with the Joint Committee of Powder Diffraction Standards (JCPDS) card number 04-0835 as shown in figure 2.
The grain size decreases with the increasing of the withdrawal speed, this is indicated that the crystallinity deteriorated by the increasing in the withdrawal speed.
Fig. 2 (JCPDS) card number 04-0835.
We observed that all the films have a uniform and dense NiO grains.
From XRD results we can see that the crystallinity deteriorated and the grain size decreased when the withdrawal speed increased.

The tests include isotropic- consolidated undrained triaxial test on small-sized specimens (diameter of 39.1mm, serial number SPCU), K0-consolidated undrained triaxial test on small-sized specimens (diameter of 39.1mm, serial number SKCU), K0-consolidated undrained triaxial test on large-sized specimens (diameter of 101mm, serial number BKCU).
Cohesion and friction are related to weathering degree because grain compositions of the soil vary obviously with different weathering degree.
Uneven of weathering degree in granite residual soil leads to obvious inherent anisotropy, when small-sized specimens are used, grain composition of the specimens in a same group vary greatly, especially that the size effect of coarse particle is strengthened, therefore experimental results of the small-sized specimens are unstable.
When large-sized specimens are used, the influence of grain composition is weakened because of the increase of specimen size, therefore large-sized specimens are regarded as even to some extent, which can be confirmed by the stability of the shear strength indices of large-sized specimens.

In addition, Latex 2 chemically contains a certain number of COO- groups and Ca2+ can form a chelate complex and consequently the concentration of Ca2+ ions could be significantly decreased by the chelating effect.
Fig. 8 shows that the absorption peak corresponding to C=O begins to drift to a higher wave number as the mp/mc is increased, this peak moves from 1729cm-1 to 1735cm-1.
NF disperses cement grains by electrostatic repulsion that results from the adsorption of the superplasticiser molecules on the surface of cement grains, but PC with graft chains disperses cement grains with the help of the steric hindrance effect that results from the extension of its graft chains away from the surface of cement grains.
The higher absolute value of the zeta potential demonstrates that more polymer particles are absorbed by cement grains.
Therefore less polymer particles are absorbed by cement grains in latex modified mortar with NF than in that with PC.

The inclusions in molten secondary AlSi7Mg0.3 cast alloy (without refining or modification; grain refined with 55 ppm AlTi5B1 and modified with 20, 40 and 60 ppm AlSr10) were removed using depth filtration by ceramic foam and pressed filter.
A number of techniques exist for the improving the cleanliness of the melt, including sedimentation, fluxing, degassing, and filtration of the melt prior to casting.
The melt was grain refined with AlTi5B1 and modified with AlSr10 (Table 1).
Table 1 Amount of additives in individual melts Melt number AlTi5B1 (ppm) AlSr10 (ppm) 1 - - 2 55 20 3 55 40 4 55 60 Four different melts (Table 1) were cast in to metallic mould without the using of ceramic filter and with the using of ceramic pressed and foam filter (Figure 1).

The results of numerical experiments with different magnetic Reynolds number are given.
The well-known positive effects of magnetic field impact on production are technological process time decreasing, grain refinement, chemical composition and temperature field homogenization.
The spatial magnetic field distribution is calculated by solution of the equation (1) with boundary conditions (2) Here Rem = m0sRm2w – the magnetic Reynolds number.
The and heat transfer equation includes Joule heat generation (5) here Fo = c/wRm2 – Fourier number; Pr = n/c – Prandtl number; Ra = gbRm3T0/cn – Rayleigh number; Q = T/T0 – dimensionless temperature; preasure is defined as , where Q = TL/T0 – dimensionless alloy melting temperature; Al = m0H02Rm2/rc2 – Alfven number; P = H02/crscT0 – parameter, that characterize ratio electromagnetic intensity and heat flux density, m0 – magnetic constant, n = h/r – kinematic viscosity, g – the gravity acceleration, T0 = 300 K – temperature scale, c=l/(rc) – thermal diffusivity.
The parameters given above changes regularities at the control parameter – Reynolds number variations are detected.