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According to the University of Columbia’s Earth Institute blog, that number is on track to reach 60 million tons by 2021.
The total number of cylindrical specimens and reinforced beams cast was 36 nos. and 18 nos. respectively.
Plastic grains sieve analysis.
However, fine grain which is fluffy and dry attracts some water molecules and makes the grains to become wet.
Within this time, there is increasing crack width, scale, number, and propagation throughout the segment.

The grain size was determined by using stereology, and Image Quality (IQ) values obtained from OIM analysis was used to distinguish the recrystallized from unrecrystallized grains.
The microstructure of the as-drawn material (Figure 2a) consisted of elongated grains, parallel to the drawing direction (DD), with a mean grain thickness (measured perpendicular to DD) of 4µm.
Patches of recrystallized grains were observed on specimens annealed for 5 min (Figure 2b) to 10 min.
The microstructure consisted of both unrecrystallized regions of elongated grains (recovered structure) and recrystallized regions of fairly equiaxed grains.
Acknowledgments The financial support given by the National Science Foundation (NSF) through the PREM program, grant number DMR-0351770 is gratefully acknowledged.

On the other hand, FERITSCOPE gives as a result the volume percentage of ferrite too or the ferrite number (FN).
The high temperatures reached in the thermal cycle of the fusion welding, leads to the coarsening of ferrite grains in the HAZ of DSS which are decorated with austenite in grain boundaries and inside the grains.
Therefore, it shows a smaller pitting resistance equivalent number (PREN).
This number is used to estimate the amount of ferrite.
This should result in a lower dilution which leads to a lower ferrite number.

And it is demonstrated that the dislocation sinks which closely spaced high-angle boundaries will reduce the number of dislocation sources during annealing [6].
It is possible to calculate the average grain size and micro-strains from the X-ray diffraction [11-13].
A dislocation density ρ can be calculated in terms of grain size d and micro-strains (<ε2>1/2) [14-16]
Lu, Structure characteristics of nanocrystalline element selenium with different grain sizes, Phys.
Horita, Determining the optimal stacking fault energy for achieving high ductility in ultrafine-grained Cu–Zn alloys, Mater.

(1) Ensure the number of the trials N, the amplitude of the white noise, and make the number n=1 (2) Perform the ith trials on the signal with white noise xit=xt+nit (1) (3) Decompose the noise-added signal xitinto a series of IMFs cijt(i=1,2,⋯M)and a residualcomponent rit.where cijtdenotes the ith IMF of the jth trial ,and M is the number of the IMFs (4) Repeat N times, and calculate the ensemble mean cjt of the N trails for each IMF.
en=an (4) Where N is the number of the ensemble, and en means the standarddeviation (SD) of error.
The coarse-grained time series at ascale factor of τ , yτ,can be constructed according to the following equation: yjτ=1τi=j-1τ+1jτxi 1≤j≤Nτ (5) 2.SampEn with unity delay is calculated for each coarse-grained time series and then plotted as the function of the scalefactor τ.
Therefore, in order to diagnostic the gearbox, MSE is applied to extract from a number of IMFs that contained the most dominant fault information.
The multiscale entropy of each coarse grained time series yτwas calculated with m = 2 and r = 0.15σ.The feature vectors and the Euclidean distanceswereshown in table 2.

The accuracy of the grain size determination was within ± 4 nm.
Prior annealing at 600o C for 30 min though resulted in some grain growth (Figure 1), the grain size of the alloy was still found to be well within the nc range (42 nm).
However, the sintering caused some further grain growth.
The grain size of the sintered pellets was determined to be 52 nm (± 4 nm).
Grain size of mc material as determined by optical microscopy was 1.5 µm.

Fig 4 The fractographies in strain rates of a-1100℃ b-1200℃ c-1300℃ 2.2 The fractography and microstructure from 1100℃ to 900℃ From the ductility curve indicated that the maximum value of RA% is 88.4% at 1000℃, its fractography was constituted by a large number of equiaxed dimples and shear dimples, as for fig5(a).
On the one hand, the inclusions precipitated in the grain boundary bring about stress concentration during deformation that are easy to damage the integrity of grain boundary, resulting in decreasing the grain boundary bonding strength, as for fig 7(b.c).
The strength of eutectoid ferrite is only a quarter of austenite[4], when the force exceeds the maximum loading capacity of ferrite, the crack will form along the grain boundaries with ferrite, leading to brittle grain boundary.
First is due to the thin layer of ferrite precipitation, and the second is because precipitated carbonitride or nitride inclusion of V, Ti, Nb along the grain boundary, causing Stress concentration. the two main reasons lead to embrittlement of grain boundary.
Influence of deformation induced ferrite, grain boundary sliding, and dynamic recrystallization on hot ductility of 0.1%～0.75% C steel[J].

Al, Si and Fe, Al9Si and TiB2 particles phases all could be found in the samples before and after T6 heat treatment, but the number of diffraction peak was increased after heat treatment.
Moreover, it was evident between coarse grain zone and fine grain zone.
However, the arc will repeat in the region of the melting trace overlap, so the accumulation of heat can cause the grain to grow up further, forming coarse grain zone [18].
The reason why TiB2 particles can refining grains during solidification is that TiB2 has some co-lattice relationship with α-Al, so a small number of TiB2 particles can become the heterogeneous nucleus of α-Al, while other TiB2 particles will hinder the growth of nascent α-Al grains, thus realizing the refinement of grains [20].
At the same time, some TiB2 particles aggregated in the grain boundary.

The value of friction-moment of friction stir welds is low and stable and abrasion principle had changed from grain abrasion to fatigue wear.
Many kind of aluminum alloy have been found suitable for a number of engineering and tribological applications where in they performed better than bronzes such as Zinc-based alloys, there has been a growing interest in the use of such alloys as sliding bearing materials[4].
The weld nugget is composed of fine-equiaxed recrystallized grains, which are formed under high rate of deformation in the weld nugget due to the pin�s stirring.
As we had known, In FSW the weld nugget is composed of a superplasticised and recrystallised structure, which makes it very fine-grained.
Microstructures of joints are comparatively fine grain and narrow HAZ zone in the FSW welds which inhibit the growth of crack and produced fine wear resistance compared to that of the base material sample. 3.

A coarse-grained W-25%Cu composite with a tungsten particle size between 2 and 10 µm is subjected to high pressure torsion (HPT) at room temperature to different strains.
Material and experimental procedures The material under investigation is a coarse grained W-25%Cu composite material fabricated by PLANSEE (Reutte, Austria).
The number of turns n is selected to attain a certain equivalent strain at radius r according to the relation 3 2 t nr eq π ε =
An increase of strain to 16 leads to a significant increase of both the fraction of broken tungsten particles and the number of deformation bands (Fig. 4c,d).
From SEM micrographs, a structural refinement in the W25% Cu composite is clearly seen as a grain refinement in the single phase materials.