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This technique employs a pulsed DC current to activate and improve sintering kinetics, the number of publications on the SPS technique has increased dramatically during the last years.
The first process is attributed to intra-agglomerate particle sintering; the second one to the sintering of grains between the aggregates and the third process is attributed to aggregate sintering.
The maximum in the shrinkage curve is believed to correspond to a change in the densification mechanism from being mainly surface diffusion-controlled to being grain boundary diffusion-controlled.
The liquid phase formation promotes grain boundary diffusion at lower densities, thus hindering the grain growth caused by surface diffusion.
Both the decrease in sintering temperature and the earlier activation of grain boundary diffusion are believed to contribute to the microstructure refinement.

Eight lactic acid bacteria strains were selected based on cholesterol-lowering ability from Chinese traditional kefir grain, named lactococcus lactis subsp lactis KS4, J4, P1 and P5, lactobacillus casei KTx, KL1 and J1 and streptococcus thermophilus Tx.
Introduction An increasing number of studies have demonstrated that high cholesterol levels are thought to be important factors induced coronary disease, hypertension and other cardiovascular diseases [1].
Materials and methods Strains and Media Lactococcus lactis subsp lactis KS4, J4, P1 and P5, lactobacillus casei KTx, KL1and J1 and streptococcus thermophilus Tx were separated from Kefir grain sampled from Baicheng City, Jilin Province in China.
L.plantarum PH04 isolated from infant feces was able to reduce the serum cholesterol to level of 7% respectively, when it was fed to hyper-cholesterolemic mice at numbers of 107CFU per mouse per day for 14 days [15].
Acid resistance test The positive ΔOD value at 600nm means that living bacterium number increases in MRS medium (pH 3.0) after culturing for12 h, and the strains are able to resist acid condition; higher positive value means stronger acid-resistant ability.

Increasing frequency of vibration and TiC content helps to improve density, thermal conductivity, thermal diffusivity and purification of the grain boundaries.
However, a review of the literature reveals that the application of mechanical, sonic and ultrasonic vibration has a number of notable effects such as grain refinement, increased density, degassing, shrinkage, and the shape, size and distribution of the second phase.
The effect of vibration to help in the promotion of nucleation and thus reducing as-cat grain size, reducing hydrogen, reducing shrinkage porosities due to improved metal feeding, and producing a more homogenous composites structure [18-20].

OSLs’ schematic structure for epoxy composite with dispersed filler: 1 – dispersed filler grains, 2 – surface layer as OSL component determined by grain surface fractality, 3 – OSLs around matrix material grains, and 4 – gel fraction.
Matrix OSLs’ structure state near filler in section normal to filler grain surface: 1 – dispersed filler grain, 2 – surface layer as OSL component determined by grain surface fractality, 3 – OSL around matrix material grains, and 4 – gel fraction.
For some fillers, the number of growth-decrease intervals may be greater.
Function (4) takes values from 0 to 1 as a measure of relative brightness in the diagrams of grain size matrices or gradients of the appearance of the OSL.
Due to the large number of filler particle pairs and the action of the law of large numbers, the graph of changes in the OSL potential of the composite acquires a smoothed shape.

The as-deposited film surface roughness decreases with the pulsed negative bias increasing, the film surface grain size increases significantly after annealing.
The Absorption edge and band gap of as-deposited and post-annealed N-doped TiO2 films prepared under different negative bias and different arc current density number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Current (A) 40 40 40 40 40 50 50 50 50 50 60 60 60 60 60 60 60 60 60 60 Bias (V) 0 -150 -300 -450 -600 0 -150 -300 -450 -600 0 -150 -300 -450 -600 0 -150 -300 -450 -600 Abs-edge(nm) As-dep/ annealed 450 460 475 430 438 520 525 503 495 480 510 550 525 488 500 520 525 525 530 550 515 520 530 525 515 521 526 540 520 528 540 558 540 525 538 525 518 520 550 530 band gap(ev) 2.7 2.6 2.6 2.8 2.8 2.3 2.3 2.4 2.5 2.5 2.4 2.2 2.3 2.5 2.4 2.3 2.3 2.3 2.3 2.2 2.4 2.3 2.3 2.3 2.4 2.3 2.3 2.9 2.3 2.3 2.2 2.2 2.2 2.3 2.3 2.3 2.3 2.3 2.2 2.3 Effect of the post-anneal on film light absorption Fig.3 shows the as-deposited and post-annealed UV-VIS transmittance and absorption spectra of the N-doped TiO2 films deposited at different current density and negative pulse biases. the absorption
The film surface grain size increases significantly after post-annealed.
The growth of many crystal grains at certain crystal face oriented formed the crystal edge on the film surface, crystal grains grow up significantly.
The film surface roughness of N-doped TiO2 decreases with the negative bias increasing, the film surface grain size increases significantly after annealing treatment.

FESEM images revealed that the particle size was agglomerated and the average grain size was about 54 nm to 66 nm.
In order to address this issue, a number of solutions have been proposed over time and one of them is to have thorough decomposition of hazardous chemicals through photocatalytic activity [1].
One of the advantages of using this method is that it permits tailoring of certain structural characteristics such as compositional homogeneity, grain size, particle morphology and porosity [9].
Fig. 2 shows a result of FESEM images of TiO2 and Fe-TiO2 that the samples were agglomerated and the grain size were estimated in the range of 54 to 150 nm.
The grain sizes were increased from 54 nm to 66 nm.

For the poor grain shape, high porosity, large water absorption, lower bulk density, high crushing value, the water consumption of recycled aggregate is rather large, the strength and elasticity modulus after hardening are Low.
In order to achieve all recycling of the waste concrete, this paper get recycled waste concrete powder by grinding the grain <0.6mm, carried out series test on the recycled concrete powder and the recycled concrete mixed with recycled concrete powder instead of slag powder, to provide the basis and reference for the use.
Influence of Particle Shaping on the Workability of Recycled Coarse Aggregate Concrete, Concrete, Number 7 in 2008(Total No.225): 66-68 [5] ZHANG Da-chang，XU En-xiang，ZHOU Xu-yang.
Number 9 in 2010(Total No.251):65-68 [6] LI Wen-xia，ZHANG Xiong，LIU Xin.
Concrete, Number 10 in 2009(Total No.240): 60-64 [7]Huang-Tianyong, Hou-Yunfen.

Their differential output was adjusted to be zero by the numbers of turns when there was no sample in the sample holder.
(1) where, NB is the number of turns of the B-coil, which corresponds to that of the compensating coil.
The larger crystal grains can be seen in Figs. 6(a) and (b).
Clear boundaries of the crystal grains could not observed in Fig. 6 (c), however the surface color of the sample C had brilliance in comparison with the other samples (black color).
It was found that this tendency had relation with surface oxidization and crystal grain size by observation with SEM.

This was true for the starting TCP-TZP-TCP laminate, as well as for once-, twice- and three-times folded laminates, whereas after a larger number of foldings and rollings the sintering cracks were not observed.
With progressive microstructure refinement the number of layers exponentially increased, the layers became thinner and wavier, and the microstructure of the composites more isotropic.
This assumption was further supported by preliminary experiments made with particulate composites containing dispersed TCP grains in the zirconia matrix.
Soc., 24 (2004) p.3351. 0 20 40 60 80 100 120 TCP 5 6 7 8 9 Number of foldings Flexural strength (MPa) Figure 4.
Dependence of the flexural strength of sintered specimens on the number of foldings.

When N content is high, γ phase does not precipitate from ferrite and is converted directly from ferrite and austenite grain boundaries.
It can be seen, the specimen with low N content is seriously corrosive, there is a large pit about 112µm in diameter, and a number of small pits on the surface.
When N content is of 0.26% , the maximum corrosion pit size is about 63µm, the number of small pits greatly reduce.
So, When N content is further increased, γ phase no longer nucleates and grows in ferrite any more, it can directly transforms from two phase grain boundaries by more save-energy method.
When N content is high, γ phase does not precipitate from ferrite and is converted directly from the ferrite and austenite grain boundary.