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However, the fine aggregate which grain size is smaller than 5mm [6], can be produced in the process of waste concrete crushing and screening.
Findings from this research will provide a theoretical basis for the application of recycled fine aggregate. 1 Materials and Experimental Procedure 1.1 Materials Natural fine aggregate: natural medium sand, from Urumqi Concrete Group Co., LTD.; size of particles, 0.16 ~ 5 mm; the third district distribution; specimen series number, TR.
We test the natural regeneration fine aggregate and fine aggregate grain size distribution, fine powder content and soil content, harmful substance content, crushing index, soundness, apparent density, bulk density and porosity, and moisture content. 2 Results and Discussion 2.1 Distribution of grain size Fig. 1 Grading curved of natural and recycled fine aggregates.
The recycled fine aggregate grain size [7] has continuous distribution, and particle size ranges from 0.15 to 9.5 mm.
ZSX1 grading curve is consistent with TR grading curve, this is due to the fact that during the process of crushing, the low strength concrete floor concrete kept the original characters, and the other recycled fine aggregates all have a large number of cement mortar on the surface, making it different from natural aggregate. 2.2 Content of fine powder and clay lump Table 1.Fine powder and clay lump content natural and recycled fine aggregates.

As shown by the optical micrographs in Fig. 1, the microstructure of IF steel consists of ferrite grains whereas the DP steel consists of mixed bainite and martensite constituents embedded in a ferrite matrix.
For the IF steel, the main hydrogen traps were dislocations, grain boundaries of the ferrite matrix, and interfaces of the fine precipitate particles (Fig. 1a).
The diffusing hydrogen atoms through iron lattice tend to interact with various defects such as dislocations, grain boundaries and particle-matrix interfaces, which are commonly called hydrogen traps.
The intensity of hydrogen-trap interaction depends on the binding energy, Eb that ranges from 10 kJ/mol to 90 kJ/mol for weak traps (grain boundaries) and deep traps, respectively.
Fray, British Patent Serial Number GB2312279

There remains a number of finishing steps to be carried out before quality control inspections.
A K2SO4 thin layer covers surface with the glass grains and prevents them from melting normally.
Thus cracks are formed between the grains of glass.
A great number of additives likely to emit SO2 are used in plasters industry. 0 2 4 6 8 10 12 14 16 18 100 200 300 400 500 600 700 température (°C) SO2 (vppm) 0 100 200 300 400 500 600 700 800 900 CO(vppm) SO2 (with 3g wax) CO (with 3g wax) CO (without wax) SO2 (without wax) Fig. 7.
The sulphated phase exhibits two morphologies (little crystals and big grains) (Fig.10).

In this context, different chemical approaches have been put forward as a viable means to obtain powders with nanometric grains [2].
The sol-gel process based on the hydrolytic decomposition of metal alkoxides has been successfully used for the synthesis of a large number of monometal oxide phases (Al2O3, TiO2, ZrO2, CeO2, Nb2O5, etc.), however, the extension of this molecular strategy to bimetallic oxides is limited to a few systems (e.g., MgAl2O4, LiNbO3) largely due to two reasons: (i) the (mis)belief that the mixed-metal compound would break-down into the homometal constituents during the hydrolysis and (ii) commercial unavailability of mixed-metal alkoxides.
The powders obtained from conventional routes are agglomerated with large and unequal grain sizes and contain varying amounts of undesirable impurities due to incomplete reactions or undecomposed intermediates.
In addition, the volume- and number-weighted size dispersions are significantly narrow for the perovskite powders obtained from alkoxide precursors (Fig. 5,6), which is not the case for powders obtained by hydroxide route due to severe agglomeration and abnormal particle growth (Fig. 6).
These processing conditions do not allow facile control over microstructure, grain size and grain size distribution in the resulting powders or shapes.

The yield indexes including number of effective ears, length of ear, grains per ear and weight per thousand grains were measured.
Effects of different fertigation treatments in rice yield and utilization rate of nitrogen Treatment Ear number per hectare Number of grain per ear Thousand grain weight(g) Theoretical yield(kg/hm2) NUE(kg/kg) S1 2220000 152.8 26.97 9148.65 24.1 C1 2550000 135.8 26.38 9135.13 27.5 S2 2120000 120.6 24.2 6187.26 10.9 C2 1820000 140.2 27.13 6922.60 17.7 S3 1760000 77.2 27.46 3731.05 C3 1530000 77.6 24.85 2950.39 　 With the same irrigation mode and 225 kg/ hm2 of nitrogen applied, calculated nitrogen fertilizer utilization rates of C1 and S1 were 27.5 kg/kg, 9.8 kg/kg higher than that of C2 and 24.1 kg/kg, 13.2 kg/kg higher than that of S2 respectively, indicating that the organic and inorganic fertilizers in conjunction played a noticeable role in improving utilization rate of fertilizer nitrogen and was an ideal mode of nitrogen fertilizer application.

In [13] the narrowing of the range of brittle-plastic transition for unalloyed medium carbon steel with ultrafine grain (UFG) structure is also established, though in contrast to [12] there is a shift towards low temperatures.
The average size of the cleavage facets corresponding to the size of ferritic grains was about 10-20 [µm].
The difference was that the number of microfractures increased with the decrease in temperature from 243 [K] down to 203 [K].
Virta, Ultrahigh strength steel wires processed by severe plastic deformation for ultrafine grained microstructure, Materials Science and Technology. 5(27) (2011) 845-862
DOI: 10.1134/S0015323018100078 (Strength and Fracture Mechanism of Unalloyed Medium Carbon Steel with Ultrafine Grain Structure under Single Loading) [in Russian]

Penetration rate increased with increasing in coarseness of the abrasive grains.
neff is the number of replicates (effective) neff = N1+[Total DOF associated in the estimate of the mean N = No. of experiments conducted in total (36×2 = 72) R = Sample size (replications).
The parametric condition for this experimental run was consisting of fine sized abrasive grains and low level of power input.
The parametric condition for this experimental run was consisting of medium sized abrasive grains and high level of power input.
A huge amount of black pits is clearly visible from the microstructure due to the dislodgement of WC grains.

The various mechanisms involving control of grain size, transformation temperature, and precipitation are now firmly established and routinely practiced.
Ashby points out that the GN dislocations are dominant at small λG , and that λG is approximately equal to the grain size in polycrystals.
(1) where: G is the shear modulus, b the Burger's vector, γ the shear strain and L the slip distance or grain size.
The rate of working hardening, θ, at 5% shear strain, in units of the shear modulus, plotted against the geometric slip distance for a number of dispersion-hardened alloys.
Concerning the formation of the austenite, the presence of Nb will cause grain refinement of the ferrite-pearlite or ferrite-bainite in the hot band (HB) coil.

Ultrafine grained theory is that the grain refinement is an effective way to improve the strength of steel without loss of toughness.
The existing studies demonstrate effective control of steel hard phase (martensite, bainite) and soft phase (ferritic, austenite), the ratio and form, can use complex phases of the organization based on fine-grain strengthening for the overall excellent performance.
Ferrite-rolling and the duplex area rolling have a large number of applications in production.
The eventual size of about 100nm granular cementite and ferrite grain size on average of about 0.3 μm of fine grained materials had got.
They combined with subsequent rapid rise to austenitic low temperature and single-pass rolling deformation after rapid cooling gain sub-micron grained steel with grain size of 200-500nm.

AZ31 alloy is among a limited number of commercialized magnesium alloys that has been largely adopted [3] and proved to have a very good formability between 400°C and 450°C [4].
Kim et al. [5] reported that in the superplastic forming process, due to a significant grain coarsening of the AZ31 Mg alloy, a comparison between alloys with different initial grain sizes could be an effort in vane.
At elevated temperatures, the extremely fast grain growth makes the alloys similar from the microstructural point of view.
However, even if this may be true for long forming times, typical of the superplastic forming process, when elevated strain rates are induced in the material, different behaviours due to different grain sizes can be encountered [6].
Yoon, Formability and grain size of AZ31 sheet in gas blow forming process, in: Procedia Eng., Elsevier, 2014: pp. 748–753. doi:10.1016/j.proeng.2014.10.071