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Introduction Porous ceramic materials offer a number of useful properties including low density, high-temperature stability, permeability, high surface area, and thermal shock resistance [1-3].
When the sintering temperature is lower, the calcium ions can escape from the zirconia lattice and enter the boundary of zirconia grains, these ions can re-diffuse into zirconia lattice when more elevating sintering temperature.

The main reason why to make them exist is that, vacancies and oxygen atoms cannot sufficiently diffuse for lack of necessary driving force so that oxygen clusters cannot smoothly form and grow at lower temperature without a enough number of vacancies and oxygen atoms, (2) When temperature is 923K or 1073K, both amount and mean sizes of the oxygen clusters gained from the simulations are relatively reasonable.
Though temperature is over high, the strong diffusion only prompts the oxygen clusters formed preferentially to absorb more vacancy and oxygen atoms and to swallow the smaller oxygen clusters around them, like as “Ostward phenomenon” in grain growth, so that the amount of oxygen clusters decreases and their mean size increase, Conclusion A phase-field simulation is presented to study the effect of annealing temperature on oxygen clusters’ evolution in silicon wafer during low temperature annealing.

The titaniferous blast furnace slag contains a large number of SiO2, Al2O3, CaO, MgO and TiO2.
Fig. 3 shows that TiO2 crystal grains appeared at 800 °C and the crystal phases were rutile and CaTiSiO5.

This means the number of the rolling stages can be reduced down to a few times to get the plate to a thickness of 1mm.
Grains are SiCp,(b) eutectic Si of the as-cast strip, (c) microstructure of the ingot cast using the metal-mold.

Table 1 The process parameters of electron beam surfi-sculpt Accelerating Voltage (kV) Beam Current (mA) Focus current (mA) Swipe speed (mm/s) Swipe length (mm) Number of swipe repeats(swipe/s) 150 2.5 342 100 4 500 Results and Discussions Macrostructure Single protrusion up to about 1.5mm in height was produced with the correct combination of parameters,as is shown from Fig.3.
The formation of the needle grains is due to the fast cooling rate during electron beam surfi-sculpt process.

However, most of the works’ attentions have focused on the influence of Lolentz force induced by the DC magnetic field and the flow melt on the suppression of melt flow and grain refinement [7,8].
The total energy of atom in the externally-applied magnetic field can be given by (2) where the is the energy of atomic system without magnetic field, is the atomic magnetic moment z-component functor, n stands for a set of quantum number.

Introduction The use of pesticides can reduce the loss of crops, increase the yield, improve agricultural production and economic benefit and increase the supply of food，But a large number of pesticides and widely used, not only a great harm to the artificial way through the food and water intake, air inhalation and skin contact, such as acute, chronic poisoning and carcinogenic, teratogenic, mutagenic effect, but also cause serious pollution to the environment, ecological balance destroyed, which caused a great impact on food safety[1].
Research on the development of rapid detection technology of pesticide residue in fruit and vegetable: Grain and oil processing..2009, 11:105-109

The results of finite-element modeling and comparison with analytical solutions are presented in a number of papers [13, 14], whereas the results of boundary-element calculations in a 3D formulation are not covered in the literature.
Governing Equations The constitutive equations for a two-phase poroelastic medium according to Biot’s theory [15, 16] have the form: (1) , (2) , (3) where is total stress in the porous material, is deformation of the elastic skeleton, K and G are bulk moduli of the elastic skeleton, is bulk modulus of the skeleton grains, is bulk modulus of the filler, is porosity, is pore pressure, is displacement of the elastic skeleton, is displacement of the filler relative to the skeleton.

The 1900ºC-annealed SiCN displays nanostructure of SiCN ceramics consists of dispersed nanosized crystallites embedded in the amorphous SiCN matrix, the grains sizes approach ~100nm.
When heated temperature rises to 1300ºC, amorphous SiCN begins to degrade and results in local atomic rearrangement (Si-, C-, N-), yielding a large number of Si-C-enriched regions and gaseous species such as SiO, CO, N2 and Si vapor.

It was obviously observed that granular ZrN existed in the products and the grain boundary was more clear when the reaction temperature rose to 1600°C.
We also thank Key Projects in the National Science & Technology Pillar Program under grant number 2011BAB03B08.