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Radford and Bratton [4] investigated the effects of a large number of additives on the sinterability of YSZ.
Below the solubility limit of Al2O3 in YSZ (0.5 mol%), grain and grain-boundary resistivities increased, and grain growth was promoted.
Although researchers generally considered Al2O3 as a sintering aid to YSZ, only a limited number have actually used nanosized Al2O3 powders [11-13].
The porosity hindered the sintered density and grain growth.
For both samples, the grain size distribution was observed to be narrow with an average surface grain size estimated at 0.40 m.

Finally, a large number of Al-6TiB2 precursors were prepared, and they were cut by a sawing machine for subsequent experiments.
It is due to the introduction of TiB2 particles that provides a large number of nucleation particles which changes the solidification mode of the melt into the barrel, and suppresses the coarsening of pre-crystallized dendrites on the barrel wall.
This number is closely related to the value of α-Al [41].
The mechanism of grain refining of Sc is different, which leads to the difference in the α-Al grains refining effect.
When 0.1 wt.% Sc is added, the grain size of α-Al is 12.7 µm, the grain size is coarse and there is little significant reduction in grain size.

The data for calculating medium size grains and histograms of grain distribution by size were received based on the results of processing the dark-fields images of 400-450 grains.
The density of grains was calculated on the 100х100 nm area.
Dependence of the grain number within the area of 100х100 nm upon the annealing temperature Ta.
This is confirmed by Fig. 3 where the dependence of the grain number within the area of 100х100 nm upon the annealing temperature Ta is shown.
It follows from Fig. 3 that at T = 500 °С, the grain number per unit of area has already become significant, with the temperature above 520 °С it is approaching saturation.

The sheet consists of a coarse-grained surface and fine-grained center layers.
The workpiece was machined with a 500mm length, a 20mm width and a 1.5mm thickness, and then subjected to CCB using a specially designed device [4,5] up to the number of passes, NCCB=20.
The grain structure of the sample is almost the same as in the fine-grained layer of 20P_A.
The surfaces were observed on the coarse grained layers with about a grain size of 64µm.
Openings and steps formed at grain boundaries make it clear that grain boundary sliding (GBS) occurred for coarse grains at both temperatures.

Calculations are performed on PBXs having monomodal grain size distributions with grain volume fractions varying between 0.72 and 0.90.
A number of thermomechanical processes occur simultaneously subsequent to impact loading and it is not straightforward to ascribe the ignition to one particular cause [7].
For h = 0.72, the temperature increases are low and only occurs at locations of grain-grain interactions.
Higher volume fractions lead to higher nominal stresses thereby enhancing grains-grain interactions and transgranular fracture.
The grain volume fraction plays an important role in hotspot spacing with a lower grain volume fraction corresponding to a larger spacing between hotspots.

Its scientific aspects cover a number of phenomena, taking place in various metal materials under deformation at PT temperatures, such as initial localization of PT in shear bands and activation of the intergranular slippage.
Treatment of measured data, that is construction of texture pole figures (PF) and determination of their parameters, was carried out by the software, including a number of specially elaborated, original programs.
by some mutual mismatching in behavior of neighboring grains.
In those cases, when under compression at PT temperatures contents of α- and β-phases in the sample are mutually comparable and their grains are sufficiently finedispersed, the intra-granular crystallographic slip proves to be restrained due to interaction of dislocations with grain boundaries.
However, many samples after deformation at 670 o and 730o C display textures, clearly originating from ideal orientations of β-Zr grains, as if the majority of initial α-Zr grains experienced PT α↔β in spite of a relatively low deformation temperature (Fig. 2-d,e,j).

Additionally, the results of previous works performed on single crystals [3,4] have shown that only a strictly defined number of possible variants of the new nuclei orientations can occur.
The map reflects microstructure and microtexture of the SB and a new grain.
The new grain with twins extends over many tens of microns.
Two groups of grains growing into T-M structure.
Once formed, the new grains exhibit a strong tendency to grow by forming new grain boundaries through recrystallization twinning and hence change their orientation.

Bioreactor Process Optimization for Bioleaching of Fine-Grained Residues from Copper Smelting Cindy Klink1, a, Juliane Heim1, b, Birgit Daus2, Sebastian Eisen1, c, Michael Schlömann1, d and Simone Schopf1, e * 1Institute of Biosciences, Department Environmental Microbiology, TU Bergakademie Freiberg, Leipziger Strasse 29, 09599 Freiberg, Germany 2Department of Analytics, Helmholtz Center for Environmental Research, Permoserstr. 15, 04318 Leipzig, Germany acindy-klink@web.de, bjuliane.heim@ioez.tu-freiberg.de, 2birgit.daus@ufz.de, csebastian.eisen@ioez.tu-freiberg.de, dmichael.schloemann@ioez.tu-freiberg.de,*, ecorrespondence: simone.schopf@ioez.tu-freiberg.de Keywords: strategic elements, fly ashes, acidophiles, bioleaching.
Theisen sludge, a fine-grained by-product from copper smelting is a secondary resource for the winning of strategic elements by metal-oxidizing acidophilic bacteria.
Introduction High-tech products nowadays often contain an increasing number of elements, some of them in trace concentrations in corresponding alloys.
All these elements occur in Theisen sludge, a fine-grained by-product from copper smelting with high toxicity.
A. ferrooxidans Ram 6F Nochten 2 Abiotic control Method Zn [mg/L] 1.900 3.150 1.530 ICP-OES S [mg/L] 2.550 2.900 1.900 ICP-OES Cu [mg/L] 20 61.5 0.45 ICP-OES Sb [mg/L] 6.30 7.60 1.20 ICP-OES Mn [mg/L] 6.10 7.20 5.0 ICP-OES Pb [mg/L] 2.95 2.90 2.80 ICP-OES As [mg/L] 1.5 1.9 0.30 ICP-OES Mo [µg/L] 10 18 6 ICP-MS Co [µg/L] 790 990 640 ICP-MS Ge [µg/L] 380 440 90 ICP-MS Re [µg/L] 260 390 220 ICP-MS Conclusion Bioleaching of fine-grained fly ashes with metal-oxidizing bacteria under acidic conditions is possible although Theisen sludge contains remarkable amounts of toxic compounds.

Therefore, enhancement of their ductility has been the subject of much research [2-4] and a number of investigations on the use of Mg alloys sheets have been conducted in search of an optimal processing condition [5-6], and the research for annealing process is also important to improve their ductility.
From Fig. 2 (a), the microstructure of the as-rolled sample shows the distribution of grains having various grain sizes.
By annealing the sample at 473 K for 10 min, the grain size of as-rolled sample becomes uniform, which the average of grain size is approximately 5 ㎛.
With increasing the annealing temperature from 473 K to 573 K, their grain becomes more uniform and grain growths can be observed in the Fig. 2 (c).
In the Fig. 2 (d), the majority of grains have grown in size.

The dispersed soft second phase Nb solid solutions with the fine grain size less than 1μm are distributed uniformly on the matrix.
Due to the effect of fine-grain and alloying addition, the toughening of the Cr2(Nb,Ti) based alloy has been fully realized.
The composed phases are difficult to be distinguished from the optical image due to the extra fine grains.
Not only that, the electron concentration is defined as the average number of electrons per atom outside the closed shells of the component atoms, which is also the number of electrons (s+d electrons) outside its inert gas shell for a transition element.
In our present work, the sum of the numbers of s-band and d-band electrons for the HP Cr2Nb-24wt.