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Tests have determined the most suitable ratio of four kinds of transition metal oxides in CM infrared powder, adjusted the sintering process parameters to improve the infrared emissivity, investigated the grain-size effect on its emissivity, and evaluated the thermal radiation properties of the asphalt concrete.
Through ratio designing, sintering process parameters adjustment, and taking the grain-size effect on emissivity into account, the infrared radiation property of CM powder is enhanced.
In this part, the powder mixture of different test numbers are sintered under the condition of heating rate 200ºC/h, sintering temperature 1200ºC, soaking time 3h, furnace cooling.
As for sample S7 and sample S8, the process of grain growth and densification is completed within 4h, same crystal structure and phase composition form, therefore the cooling method of air quenching used after sintering for 4h does not improve the infrared emissivity evidently.
Tests have determined the most suitable ratio of F oxide, M oxide, C oxide and T oxide in CM infrared powder, adjusted the sintering process parameters to improve the infrared emissivity, investigated the grain-size effect on its emissivity, and evaluated the thermal radiation properties of the asphalt concrete.

Currently, mass construction does not have the necessary number of sound-proof products and this demand is constantly increasing.
With the expansion of obsidian with grain sizes from 5 to 20 mm in a duration of 3-10 minutes at temperatures from 1050 to 11500С, it is possible to obtain a lightweight porous material with the lowest average density of 200–350 kg/m3 (in a piece of stone) and thereby solve environmental issues - to recycle production wastes.
[13] Safaryan A., Sargsyan T.,  Kalantaryan M. and  Melyan H., Ultralight large grain porous material - expanded obsidian, E3S Web Conf. 97 (20190 02038) (2019) 1-7

Physical properties of soil such as density, Atterberg limits, water content and grain size are important for liner design, in addition, hydraulic conductivity lower than 1 x 10-7 cm/s, mechanical strength, at least 5 N/mm2, and good compaction conditions are the most significant factors for liner performance [5], [6].
Particles in range 10 – 75μm were discarded as consequence of their low number, this range were statistically ignored because of its small number compared to the number of smaller particles.
Considering the coarse portion, D50, D90 and SS respective values are 150-860 μm and 320 cm²/g, coinciding with literature range of 100-1000 μm for standard grain sizes [18], [19], although the compared studies [15]–[17] have shown an even finer general granulometry, indicating WTS’s filling properties.
Initial results indicate their possible feasibility as filling-material while possibly containing a low number of voids due to their fine granulometry, although a larger number of tests have to be conducted to confirm these characteristics due to WTS’ variability.
Also, according to analyzed studies, they seem to contribute with pozzolanic characteristics, due to their inherent high amount of silica minerals, creating a silica-gel that connects grains and structural layers while minimizing porosity within the soil, increasing its bearing capacity.

Then was recalculated until the deviation between calculated values and measured values is within the error range or the number of times exceeds the maximum number of iterations.
Different laminar cooling strategies not only make a difference in the cooling rate, but also affect grain size and microstructure of the strip.
Forward cooling applies to the steel requires to control the organization state of austenitic with deformation, prevents austenite grain growth, becomes solid because of the dislocation caused by deformation curing and decreases the phase transition temperature.
After checking and pre-set computing cooling capacity, with certain inlet conditions, both opening the appropriate number and choosing right location of the manifold can make strip’s coiling temperature within a predetermined range of appropriate.
With the same number of cooling tubes opening, the cooling capacity of the backward cooling is the strongest followed by sparse cooling and forward cooling is minimum.

Introduction The growing need for multifunctional materials and the continuous miniaturization of devices leads to the development of new composite materials with grains in the nanometre range and/or nanosized phases.
The mechanical properties of each phase of these nanocomposites are then strongly influenced by the high surface to volume ratio of the grains and their plasticity is ruled by size effects.
Common features are observed for the Cu matrix in the three systems: Cu channels with a width (dCu-i) larger than few micrometers are mainly composed of grains in the 200-400nm range (few large grains in the micrometer range remain, but their presence decreases in very fine wires).
The grains in the Cu matrix are strongly elongated in the wire axis direction and are strongly <111> textured, with a remnant <200> texture component reappearing after heat treatments.
Two scattering configurations were used: the neutrons scatter onto crystallographic planes that are parallel or perpendicular to the tensile axis, giving respectively transverse and axial strain in individual Cu and Nb grain families.

The surface morphology and grain size of ASO thin film were determined by FESEM top view images.
The sample having identical gran size and sticking grains in the range 36.2-48.6 nm.
Furthermore, the surface mode is believed to be due to the softening of the lattice that occurs the outside the grains, which is like an abnormal lattice of the skin around each grain [37].
This condition pushes a greater number of Al atom doped into SnO2 lattice either via loading in the O atomic vacancy or by occupying the position of the Sn atom owing to substitution.
The electrical properties of this films may be also affected by microstructure, crystallinity and grain sizes of the sample since the large and homogenous grain size would facilitate electron mobility [32].

Reinforcing grains can be partially dissolved in the alloy-bundle, deteriorating the properties of the composition.
The minus material includes a grain size 0-0,04 mm, and the plus material- 1,6-2,5 mm.
However, the main disadvantage of this method is the capture of the inert gas into the center of the spherical grain and a large number of non-spherical particles [6].
The results obtained in paper [10], indicate that the rotary atomizationprovides higher mechanical characteristics of the cast tungsten carbide due to the formation of more uniform compared with crushed powders fine-grained structure (Fig. 3 d), caused by high cooling rate, as well asby absence of visible surface defects (Fig. 3a, b).
As the result we have achieved the increasing of dispersion of the obtained powders, the stability of their grain-size composition, to reduce the number of non-spherical granules in the production of powders from high-melting-point materials at the account of the molten particles deviation from the plane of expansion under the action of centrifugal force by the flow circulating in a closed circuit of the cooling gas mixture passing through the channel formed between the cylindrical billet rotating in the holder and a water-cooled copper disk, additional cooling by it of particles in flight.

The strength of a material in nano-structured condition is enormously higher as compared to ordinary coarse-grained materials.
To date modification processes of joint welds are significantly important for machine building, since a great number of products are manufactured with the help of various welding procedures.
NaF or TiO2 nanoparticles, added in a percentage of 1% by mass had a positive effect on the grain size and penetration depth.
The results demonstrate that the growing amount of the nano-additive results in gradual refining of primary austenite grains and improves mechanical properties of the coating.
Duh, Martensite nucleation site and grain refinement in duplex titanium alloy weldment by active flux with nanoparticle addition, Sci.

Both types of samples gave a low number of results with high toughness in the side zones of the slab and in the slab centre too.
While on the surface a fine-grained surface skin regularly appeared, under that the columnar dendritic microstructure developed and around the slab center globular crystals could develop.
Heterogeneities can be of different nature, like grain size, microstructure type, chemical composition changes by precipitation, or segregation in the slab surface zone.
According to Chakrabarti et al [4,5] as well, bimodal grain structure can have significant effect on the toughness.
Strangwood, Characterisation of bimodal grain structures in HSLA steels, Materials Characterization, 58 (2007) 423-438

Ti4+ can be replaced by Mg 2+, negatively charged defects TigM '' will be formed, and a corresponding number of positively charged oxygen vacancies will be required to satisfy the site balance and charge neutrality conditions.
These behaviors are due to the different shell structure between MgO coated and mixed BaTiO3 as discussed in the previous study [5], because coated MgO is uniformly distributed in BaTiO3 grain boundaries.
A significant reduction in grain size was observed at ≥1.0 mol% MgO, compared with the un-doped BaTiO3 regardless of the sample preparation techniques.
This could be due to the different Mg diffusion processes into BaTiO3 grains.
A significant reduction in grain size was observed at ≥1.0 mol% MgO compared with the un-doped BaTiO3.