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The mechanical properties of magnesium alloys are closely related to their microstructures.
Even if the initial content is identical, the different microstructures may be obtained under different solidifying conditions, resulting in different mechanical properties.
The size of grains is an important factor affecting the mechanical properties, the finer the grains are, the better plasticity of metal is, however, there are few reports about studying on the solidified process of magnesium alloy under different electromagnetic fields.
The key factor lies in the inherent characteristics of crystallic substances and the temperature distribution adjacent to solid and liquid interface during solidification.
When DC and magnetic field were applied, magnesium melt did not vibrate, thus the grain morphology were almost not affected by magnetic field.

This paper calculated pillar load of the first stage and stowing body load of the second stage with enlarge pressure arch theory, determined stowing and mining interval width in two stages and stowing body strength in the first stage combined with safety factor.
(2) the safety coefficient of pillar In order to guarantee the pillar has enough bearing capacity, it is necessary that the safety factor of pillar is no less than 1.5,and this can meet the requirements of long-term stability of pillar.
Strength of filling body requirements according to the inverse calculation of safety factor formula for filling column,the load on filling according to the theory of expanding pressure arch (according to the mining area filling area and filling body in column total width).in 1~3 replaced coal by filling body, combining with the practice, in proportion to the number of coal pillar mining without filling for 5 mining area (i.e., 59.4 m), filling the column safety factor F = 1.5, filling body strength index was 5.6 MPa.
Compared with the filling body in first phase of, it is always in the triaxial state,is low strength requirements,but the strength of filling body has correlation with compression ratio and bearing capacity, thus affecting rock movement control effect.therefore,determining the strength of filling body in second stage mainly based on meeting the strata movement control requirements.
In order to improve the reliability of simulation results, the use of surface subsidence of the mine 2301 working face of the measured data of simulation parameters optimizing fitting, eventually making the simulation of 2301 face surface subsidence parameters was consistent with the test result, the numerical calculation model of bedrock and the topsoil of block division and the mechanical parameters of rock and joint, according to the physical property of the result of the experiment, filling model in the first stage filling of strength parameters are shown in Tab.3.

Microstructure was examined and mechanical properties including hardness and stress-strain relationship were also investigated.
Metal forming may also improve mechanical properties through texture evolution and work hardening.
The grain size is one of the main factors leading to size effects and affects the plastic behaviour of material in the micro metal forming process [2].
Working hardening is important for the superior mechanical properties of cold formed parts.
The result also means that the mechanical properties might be varied from part to part due to the random character of the grain structure, especially for the parts with relatively large grains.

Silicon nanocrystals (SiNCs) have unique optical and electronic properties that are advantageous for semiconductor device applications and here their application to solar cell is presented.
As the weight fraction of SiNCs increased up to 50 wt%, the short circuit current and the power conversion efficiency dramatically increased, while the open circuit voltage and the fill factor do not change significantly.
For the hybrid devices, the Voc (ca. 0.5 V) and the FF (ca. 0.35) were not strongly affected by the SiNC weight ratio.
Spectral electron generation property clearly indicates that P3HT is the main photon absorber in the visible spectrum range to generate excitons.
SiNCs exhibit strong UV photon absorption property [16].

The economic and political factors are greatly associated with their Appropration.
They are related to the economics and properties of biodiesel.
The properties studied were the flash and fire points, cloud and pour points and viscosity.
Fuel properties The flash point of the fuel gives an indication of the volatility of a fuel.
The fuel properties were measured using ASTM standard test methods.

Characteristics of Hot Ductility and Fracture in Micro-Alloyed Q345B Structural Steel Fang Dong, Cheng Sua and Yuanyuan Bai Meterial and Metallurgy school ,Inner Mongolia university of Science and Technology,Inner Mongolia, Baotou, 014010, china aSlz851006@163.com Keyword: Microalloyed Steel; Fractography; High Temperature Mechanical Property Abstract.
Experimental method The composition of the tested V-Ti-Nb microalloyed steel is shown in table.1, tested specimes were machined to cylindrical samples with a diameter of and a height of , then electrically heated by using computer servo-controlled Gleeble-1500D thermal mechanical simulator to 1200°C at a heating rate of 20°C/s and then continuous heated to 1300°Cat a heating rate of 10°C/s, at this temperature point, the tested simple was homogenized for 120s to dissolve any precipitate, subsequently cooled at a cooling rate of 3°C/s which is close to the practical cooling intensity of secondary cooling zone of slab when it goes out of the mould to the deformation temperature, holding for 60s in order to eliminate the thermal gradient before deformation.
On the other hand, the factor of dynamic recrystallization that can be reflected by the true stress-strain curves also is important to affect the ductility, shown in fig 6, it is well known that the kinds of curves are generally divided into three categories: work harding,dynamic recovery and dynamic recrystallization, and dynamic recrystallization will improve the ductility by refining grain and prompting grain boundary migration[4].
(2) In region I which is close to the melting point that below the experimental temperature of 1300°C, the liquid phase causes the embrittlement, and ductility does not depend on the strain rate; In region II which corresponds to stable austenite region, embrittlement occures along grain boundaries as a result of intergranular precipitation, only in higher strain rate; In region III which covers temperatures of 900°C to 700°C, the ductility trough locate in 800°C, the degree of the embrittlement increases as the rate of deformation decrease, this embrittlement is caused by such factors as intergranular precipitation, formation of proeutectoid films along austenite grain boundaries, and grain boundary sliding

TiO2 coating is applied to provide antibacterial properties.
Meanwhile, the two main factors of TiO2 application as photocatalyst are its chemically inert and low toxicity properties [6].
The photocatalytic properties of TiO2 depends on the crystallinity of the thin film [7].
Effect of TiO2 Coating on Antibacterial Properties.
Zakharieva, “Titanium dioxide thin films: Preparation and optical properties,” J.

Electromagnetic field, fluid flow, and temperature distribution are important factors in EMS; as such, these factors have been extensively investigated.
The main thermal and physical properties of the slurry used in the calculation were listed as follows: for AlSi9Mg alloy, density = 2480 kg/m3; thermal conductivity = 152 W/(m·°C); specific heat capacity = 973 J/(kg·°C); resistivity = 2.1 × 10–7 W·m; relative magnetic conductivity coefficient = 1; and relative magnetic conductivity coefficient of silicon steel magnet yoke = 2000.
This result suggests that magnetic flux density is greatly promoted by increasing I, thereby affecting the value and uniformity of magnetic flux density.
Stirring frequency mainly affects the uniformity of EMF, whereas stirring current significantly affects the value and distribution of EMF.
Lee, The effect of solid fraction and indirect forging pressure on mechanical properties of wrought aluminum alloy fabricated by electromagnetic stirring, Int.

Introduction Thixotropic and antithixotropic materials show time-dependent properties.
In this paper these equations and some of their properties will be analyzed in rheological behavior context.
More than one type of structure can exist in a fluid, and each can be affected in different way by the shear rate.
The factor is called the coagulation factor.
Ferry, Viscoelastic properties of polymers, 3rd Edition, Wiley, 1980

These factors translate to improved hot formability.
This paper will present the effect of scaling up on the mechanical properties, microstructure, and the hot workability of the alloy from the laboratory scale (12.5 mm) to industrial scale (100 mm).
The use of SPD processed material, therefore, has not adversely affected the measured service properties.
Table 2: Properties after forging and heat treatment Properties after T6 Grain size Stock Material Forging Temp.
Langdon, "The potential for scaling ECAP: effect of sample size on grain refinement and mechanical properties," Mater.