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Introduction Equal channel angular pressing (ECAP) is an effective route to refining coarse-grain size into submicrometer or nanometer regime by means of large plastic shear deformation, which was first introduced by Segal [1].
The most advantage of ECAP is that the billet undergoes severe plastic deformation (SPD) but remains the same cross-sectional geometry so that it is possible to repeat the pressings for a number of passes in order to achieve a very high total strain.

Powder morphology and grain size were directly imaged using scanning electron microscopy (SEM).
These could be matched with JCPDS file number 06-0452 [11].

A number of alloying elements have been added to Mg-Al alloys to gain better high temperature mechanical properties, however most of them show some drawbacks such as low castability and high cost [1].
SEM-EDS investigations showed that some RE-containing phases were formed adjacent to Mg17Al12 phase at grain boundaries, but Sb-containing phases could not be easily found.

Table1 The type of uranium mineral in Bayanwula area and the result analyzed by EPMA Sampling area Sample number sample position UO2 SiO2 Al2O3 CaO P2O5 FeO TiO2 SO3 Total uranium mineral Bayanwula area 1 BZK311-81 134.5m 61.73 34.68 - - 0.01 0.02 - - 101.06 coffinite 85.04 7.194 1.75 0.16 0.01 - - - 100.97 13 BZK479-16 95m 28.90 14.46 4.64 10.59 17.87 0.94 - - 78.54 Uranium phosphate 10.64 2.06 - 0.77 23.22 0.32 - - 36.81 uranothallite 10.96 2.79 0.59 1.99 28.70 0.43 - -　 46.29 14 BZK399-101 122.5m 8.34 12.87 -　 1.19 0.466 1.48 1.61 1.61 85.34 6.73 12.44 -　 1.58 0.716 1.21 2.01 2.01 82.04 18 BZK391-101 118.9m 14.27 3.26 1.16 8.42 1.84 0.59 2.249 2.249 64.68 isomorphous uranium 15.73 2.46 1.29 7.98 1.27 0.76 2.84 2.84 64.92 Indicate：“-” representative below the detection limit Conclusions Uranium mineralization occur in the middle and lower layer of Saihan formation in Bayanwula area.
The coffinite of the exposed in the main quartz grain voids, uranium thorium along the pyrite, white iron ore on the edge of the distribution,and isomorphous uranium mainly paragenesis with Ce .

Because metallic glass has no grain boundaries and there is a specific slip plane in the crystalline alloy, metallic glass has excellent mechanical properties not found in conventional crystal metals [1-3], including high strength, low Young's modulus, high corrosion resistance and high magnetic resistance.
The results are shown in Figs. 7-9 (circles mean mother number is 40-50, error bars indicate standard deviation).

Improved glass-forming ability (GFA) is thereby a possible consequence of the enhanced stability of ISRO, and a large number of Zr-based bulk metallic glasses (BMGs) with large GFA have been obtained accordingly [3].
Fig. 3 (a) shows the nanometer scaled microstructure with the grain size of about 50 nm.

This phase is less noble than the other constituents of the magnet, and is susceptible to preferential corrosive attack when it is exposed to a number of electrolytes.
The secondary electrons image reveals differences in contrast inside some grains showing that some of the phases present variations in composition [6].

Impact compressive experiments of BFRC Raw material and mix proportion The following raw material were used in the fabrication of the BFRC specimen: ordinary 42.5# Portland cement, coarse aggregate with 5-10mm grain diameter, medium sand with fineness modulus of 2.5, ultrafine and super-short basalt fiber, Water reducing agent, 500 mesh silicon powder, ordinary fly ash and tap water.
Table.2 Experimental results Number Fiber content(%) /MPa ×10-6 /(1/s) Failure mode of specimen AV0S2-01 0.0 68.8 4540 32.0 Broken into pieces AV0S2-02 0.0 66.6 5260 32.3 Broken into pieces AV0S2-03 0.0 72.7 4610 31.2 Broken into pieces AV1S2-01 0.1 77.0 4300 27.1 Crack and do not come loose AV1S2-02 0.1 71.0 4140 27.4 Crack and do not come loose AV1S2-03 0.1 77.8 3850 23.9 Edge crack AV2S2-01 0.2 79.2 4040 24.3 Edge crack AV2S2-02 0.2 67.6 3870 25.0 Edge crack AV2S2-03 0.2 65.8 3960 25.5 Large crack AV4S2-01 0.4 64.8 3520 25.9 Edge crack AV4S2-02 0.4 60.8 3410 22.5 Edge crack AV0S1-04 0.0 58.8 3130 15.3 Fine cracks AV0S1-05 0.0 63.5 3450 17.8 Fine cracks AV0S1-06 0.0 58.1 3450 18.8 Fine cracks AV1S1-04 0.1 63.0 3340 18.6 Fine cracks AV1S1-05 0.1 574 3110 16.3 Fine cracks AV1S1-06 0.1 57.4 2890 15.0 Fine cracks Continue of table 2 AV2S1-04 0.2 62.0 3500 18.6 Fine cracks AV2S1-05 0.2 64.4 3350 18.7 Fine cracks AV2S1-06 0.2 61.1 2780 14.8 Fine cracks AV2S1-04 0.2 51.9 3300 17.8 Fine

Annealing is the process of recrystallization which helps to reduce the surface state of grain and makes the crystallization of samples more completely.
It can reduce the number of nonradiative deathnium center and help to enhance luminous radiation of band edge transition.

The two distinct long lifetimes namely �3 and �4 are ascribable to ortho positronium annihilation in micro cavities within the molecular grains and inter granular mesoscopic pores respectively.
Discussion and Conclusion To handle a large number of experimental data, the most common trend has been to use TaoEldrup model [6] for small cavities based on spherical well potential with infinite walls and a virtual electron layer of fixed thickness somewhat empirically added to the inside of the cavity wall to make the possibility of overlap of the Ps wave function.