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Most high-performance beams that are used in construction are made of structural steel [1-4] (steels that are abbreviated by the letter S followed by a number) and although these steels are categorized in this manner by engineers for a while now, going back 100 years there were not standards for them and neither such a good understanding of metallurgy as it is now.
The 160 beam’s steel is vastly different in grain size and form, but the amount of carbon seems to be more similar, which is logical since the 160 beam’s steel is higher in carbon and closer to the amount of carbon found in S235’s composition.

This fact makes it difficult to identify the phases and their number.
Alfimova, The method of creating and measuring the printability of fine-grained concrete, Materials Science Forum. 1017 (2021) 71-80

Wang [10] found that rare earths mainly hinder the diffusion of Fe atoms by gathering around the iron rich phase, resulting in the refinement of the primary iron-rich phase When the amount of Rare Earth added is too much, Sun [11] and Li [12] believe that La and Ce will preferentially form a large amount of Rare Earth compounds, thereby reducing the number of element atoms freely enriched on the solid/liquid interface of the alloy, resulting in reducing the constitutional supercooling and weakening the refinement effect.
Li, Grain refinement mechanism of as-cast aluminum by hafnium, Transactions of Nonferrous Metals Society of China. 26(12) (2016) 3059-3069

(5) where: k – thermal conductivity of used wood sample in W.m-1.K-1 ρ - density of sample in kg.m-3 c – specific heat capacity of sample in J.kg-1.K-1 α – thermal diffusivity of used wood sample in m2.s-1 THERMAL PROPERTIES OF WOOD: For moisture contents below 25%, approximate thermal conductivity k across the grain according to [2] can be calculated with a equation (6) k=GEMC.0.1941+0.004064.EMC+0.01864
Table 3 Values of total heat transfer coefficient h, radiative heat transfer coefficient hr, convective heat transfer coefficient hc for aluminium sample Property h(W.m-2.K-1) hr(W.m-2.K-1) hc(W.m-2.K-1) Value 50.22 1.69 48.53 Statistical parameters of the cooling curve with the value of the Biot number [11] are shown in Table 4.

The number of passes amounted to 10.
The interfaces and possible grain boundaries can deflect or reduce the cracks propagation and stress concentration.

It has a number of applications in transformers, choke coils, noise filters, electromagnetic gadget, memory of data storage devices [2].
With increasing calcination temperature to 650 oC the nanoparticles appear to crumble, further increase in temperature to 650 oC the grain appearance metamorphosed as shown in Figure 3(c–d).

Due entry of high temperature during welding occurred coarser of grain perlite.
Basic parameters for testing are: abrasive: quartz sand; speed impact of abrasive in sample: 24.265 m/s; duration of testing: 13’ 53’’; number of impacts: ≈ 20000.

(a) ε=0.3 (b) ε=0.5 Fig.4 Power dissipation map (The numbers represents percentages of dissipation factor η) The calculation method of the variation of )( .εξ is similar to the calculation method of the efficiency of power dissipation.
The coarse grains that are generated at the high deformation temperature have an enormously bad influence on the mechanical working properties (shown in Fig.8).

Furthermore, a large number of facts showed that high lead content in environment influence children's blood lead, intelligence and behavior [ 4].
The results showed that the soil heavy-metal contamination in Heilongjiang Province was relatively minor, that is to say, the environment of crops growth was good, the quality of grain and other agricultural products were benefit to the people's heath.

Fig.1 was the SEM image of nano-TiO2 powder, with a large number of nanoparticles appearing, which were spherical and distributed evenly.
By the FWHM method, the average grain size of the sample was calculated according to Scherrer Formula [6].