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Modal Analysis of Montmorillonite in bentonites Using Phase Mixing Equation Ge Li, Hongwen Ma, Meitang Liu, Jiaping Zhang, Hongli Wang National Laboratory of Mineral Materials, China University of Geosciences, Beijing 100083 Keywords: bentonite; montmorillonite; modal analysis; Phase Mixing Equation Abstract: Based on the mass balance principle, mineral contents of the bentonites from Yangxian of Shaanxi province, Queshan of Henan province, and Chifeng of the Inner Mongolia Autonomous Region were estimated by resolving the Phase Mixing Equation constructed from the data of X-ray diffraction, microprobe analysis of montmorillonite grains, and chemical anaysis of the bentonites.
（3）Where wp is the abundance value; Z is the number of molecules in unit cell; S is the scale value of Rietveld analysis; M is gram formula weight, V is cell volume.
Table 5 Microprobe analysis of MMT grains in the bentonites（wB /%） Sample SiO2 TiO2 Al2O3 FeO MnO MgO CaO Na2O K2O Total YB-06/7 52.92 0.70 22.60 5.20 — 1.92 1.25 0.25 2.46 87.31 QB-07/7 53.00 0.07 21.23 2.01 0.17 2.02 0.57 0.09 0.03 79.19 CB-08/20 57.48 0.22 15.39 4.07 0.10 4.63 2.16 0.31 0.06 84.42 Note: The total iron is regarded as FeO; Sample number is the number of electron microprobe analysis points; The results were analysized by Jingwu Yin of electron microprobe laboratory in China University of Geosciences (Beijing) .
YB-06，(K0.22Ca0.09Na0.03)0.43(H2O)n{( Al1.49Fe3+0.30Mg0.20Ti0.04)2.03[(Si3.65Al0.35)4O10](OH)2} QB-07，(Ca0.05Na0.01)0.11(H2O)n{(Al1.72Mg0.22Fe3+0.12Mn0.01)2.07[(Si3.89Al0.11)4O10](OH)2} CB-08，(Ca0.16Na0.04K0.01)0.37(H2O)n{(Al1.28Mg0.49Fe3+0.12Fe2+0.09Ti0.01)1.99[Si4.05O10](OH)2} According to the results of MMT lattice constants C0, the number of H2O in crystal chemical formula is 14.
Based on the phase mixing calculation of grain micro-area component of MMT（~1mm）, MMT content equals to 59.5% (including mixed-layer muscovite).

, (1) , (2) where A is the grain area, and P is the perimeter of the grain interface.
The closer the average value of the shape factor F is to 1, the rounder the primary crystal grains are.
The average size and shape factor of the α1-Al grains and the secondary grains were calculated and are shown in Table 3.
However, for ACSR rheological die-castings, a large number of small and nearly spherical α1-Al grains are observed in the microstructure, and the internal defects of the castings are reduced significantly.
Higashi, Review processing and mechanical properties of fine-grained magnesium alloys, J.

SnO2 is a semiconductor material of the n-type that exhibits a comparatively limited number of oxygen adsorption sites in comparison to noble metals.
The average grain size of both doped and non-doped SnO2 films was determined through AFM analysis using software.
Table 2 provides details regarding grain size, roughness, and root mean square values for all the films.
These images reveal a uniform and fine-grained microstructure with minor porous regions.
This decrease in crystallite size is attributed to the increased number of nucleation sites resulting from the higher stacking fault energy caused by copper addition to SnO2.

Actual developed stage in casted form from hardened steels present the disadvantage of being sensitive to excavation, pitting type, wear, in hard areas or in those with segregation at the crystalline grain limit.
Thus in the central impact and wear area, under abrasion and high pressure, depositing the self-protection at wear system consists of alternative rows of tough, hardened, with small grain size materials; in the side areas, subjected to the constant grinded material fall, deposits developed with tough materials.
Acknowledgements: This work was supported by a grant of the Romanian National Authority for Scientific Research, CNDI– UEFISCDI, and project number PN-II-PT-PCCA-2011-3.2 – 0918.

The cell radius was determined from an observed number density of particles.
Although the shape of the grains was not well defined it was assumed that the morphology was spherical.
It can be argued that the sphere radius should be 0.81 times the intercept length of the grain structure [6].
The σ-phase is assumed to grow as a spherical shell around the austenite grains with a radius of 0.81 multiplied by the mean intercept length of the grain size.
The niobium carbonitrides were placed in the centre of the sphere while σphase formed a spherical shell around the austenite grains.

Height of raised part is 70mm, so it is difficult to fill mold completely and there are a number of defects such as filling incompletely, shrinkage porosities and cavities.
Grains of SiCp are uniformly distributed without any defects such as segregation, obvious pores, inclusion and oxidation.
Grain boundaries are combined well at the meantime.
The grains of SiCp are distributed in creeper tread of composites.
When grains of SiCp and aluminum alloy are mixed together, hardness of the composites is also high.

The average grain size calculated for (200) by the Scherrer formula shows that the grain size is almost constant, with a little tendency to increase with the increase of Ts.
For sample deposited at 580°C (Fig.2a), the grains are irregularly aggregates with a rough surface.
The grain sizes of MgO films slightly increase with substrate temperature, which agrees with the result of XRD analysis.
This process gives rise to films with irregular or edge-like grains (Fig.2a).
In addition, when annealed in oxygen, through the recombination of Mg and O, oxygen helps to decrease the number of excess Mg carriers, which also contributes to the high resistivity of the film.

In addition, the annealing twins of the microstructure grow up from the boundary of austenite to the interior of the grains, and there are many steps at the interface of the annealing twins, but these steps are different in height.
The second phase that is lamellar appeared gradually in austenite grains, but the precipitation was not complete.
Most of the discontinuous second phase precipitated from the primary austenite grains at the core of the sample has evolved into lamellar.
As shown in Fig. 3(b), all piece of layered organization in austenitic grain after 1050℃ treatment has broken.
Table 2 Hardness test results of alloys with different treatment processes water cooling Solid solution slow cooling spheroidization HRC 29.3 61.3 48.3 It can be seen that the test alloy has a large number of the second precipitation nitrides in the process of solid solution slow cooling, and it has high strength.

This can be explained that the number of sputtered Si molecules at the target increases due to the enhancement of bombardment by argon ions as the RF power increases resulting in increase of the thickness.
The morphology of nc-Si films deposited at room temperature was found to be continuous and the grain cannot be seen clearly.
Grains are seen to be agglomerated.
The particle (agglomerated grains) sizes are around 34.86 nm at this point.
At 150oC, it appears that the grains can be seen clearly and the value of particle size around 43.25 nm is obtained.

Since the introduction of the semi-solid casting technology, research has been focused on a number of factors, including the semi-solid slugs’ preparation process [4], semi-solid thixoforming and rheology process control [5], the mechanism controlling the formation of the semi-solid microstructure [6], and numerical simulation of semi-solid flow [7].
Using a high pouring temperatures of 690 ˚C and 675 ˚C, the primary α-Al grains consist of coarse dendrites from center to edge.
When the pouring temperature was reduced to 660 ˚C, the primary grains size and morphology was less dendritic.
When increasing the pouring temperature to 660 ˚C, the primary α-Al grains begin to gradually gather together to form rosette-like grains, and minor segregation occurred in the direction of the flow.
Effects of Grain Refiner on the Microstructural Evolution during Making Semi-Solid Slurry of the A357 Alloy[J].