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Axial Number Transverse Number 1# 2# 3# 4# 5# 6# 7# 8# 9# 10# 1# 7.94 7.88 7.88 7.77 7.68 7.17 6.85 6.67 7.78 7.35 2# 7.85 6.57 6.04 8.15 6.96 6.70 6.59 6.56 6.71 6.90 3# 8.30 7.20 6.49 7.35 8.18 6.90 4.37 5.41 6.31 4.64 4# 8.12 6.97 6.00 8.13 7.76 3.83 4.60 4.81 5.19 6.74 5# 6.61 6.48 5.92 7.65 8.01 3.49 2.78 5.71 4.80 4.39 6# 7.07 7.12 5.95 6.40 7.63 5.60 6.05 6.08 6.25 6.84 7# 7.32 6.74 6.51 6.54 6.71 7.08 4.49 6.27 7.07 5.82 8# 7.39 7.16 8.01 7.07 7.83 6.78 7.79 7.12 7.97 7.42 9# 7.19 8.00 7.28 7.87 7.95 7.07 7.23 7.97 7.22 6.90 Physical Testing and Chemical Analysis l Using an ARL 4460 direct-reading spectrometer and a LECO TC600 oxygen nitrogen analyzer, the chemical composition analysis of the pipe body was performed according to GB/T 4336-2016 [7] and GB/T 20124-2006 [8].
Subsequently, its metallographic structure was observed on a MEF4M metallographical microscope according to GB/T 13298-2015 [12], and the grain size was graded based on GB/T4335-2013 [13].
The microstructure of the pipe is composed of polygonal ferrite (PF), pearlite (P) and granular bainite (GB), and the grain size was 11.0 μm.
[13] GB/T4335-2013, Determination of ferrite grain size for cold rolled low carbon steel sheets.

And Nb is usually used for controlled rolling in order to decrease the grain size for strengthening and toughening.
The strength and impact energy of the plates after rolling and cooling are shown in Fig.1, in which the air-cooled sample are designated by adding -1after the steel number, and water-cooled sample, -2.
Fig.1 Strength (a) and impact energy at -40°C (b) of air- and water-cooled samples of Steel 1-6, in which -1 after the steel number represents air-cooling, and -2, water cooling.
In Steel 3, quasi-polygonal ferrite is obtained under both cooling conditions, but water-cooled sample has much smaller grain size air-cooled sample.
This may be due to the segregation of Nb in the austenite grain boundaries which hinders the nucleation of ferrite.

However, this will only occur if the subgrains are able to grow larger than a certain size, RC, as described by the following relationship: ZD GB PP RcR − ⋅ => γ4 (1) where RC is the critical radius for nucleation, γGB is the specific grain boundary energy and PD is the stored deformation energy.
These dispersoids nucleate rapidly at high number densities, are homogeneously distributed and coarsen quite slowly [4].
The furnace temperature was approximately 700°C and Al5wt%Ti1wt%B-grain refiner was added at a concentration of 1 kg/ton.
The grain structures were then studied in the longitudinal section by polarised light in a Leica MEF4M-microscope.
The structural stability of this variant can partly be attributed to the presence of Al3Zr, but in areas where the number density of Al3Zr is low, the structure is most likely also stabilised by small Mn-bearing phases and Mn in solid solution (solute drag).

In addition, average grain size of the sample material was determined by the Scherrer equation as shown in Eq. 1 by employing tool introduced in [12].
The hardness number is reported as an average of five measurements.
Wear test configuration Results and Discussion Table 1 shows the elemental composition of the as-cast gray cast iron sample, and it can be seen that silicon and manganese are the main alloying materials with small number of additional elements.
The decrease of these crystal sizes is thought to enhance the hardness and wear resistance characteristics of the quenched sample, since the increased grain boundaries facilitate dislocation interactions, hence impeding dislocation movement.
[12] InstaNANO, XRD Crystallite (grain) Size Calculator (Scherrer Equation), (n.d.). https://instanano.com/all/characterization/xrd/crystallite-size/ (accessed May 29, 2024)

Based on this, the “DL/T 5145-2002 Design calculation technical regulations of coal-fired power plants pulverizing system ", the standards of volatile in coal and the explosibility are studied and confirmed through a large number of experimental research, as is shown in Table 1.
By the formula, when container’s volume is certain, combustion rate is proportional to pulverized coal concentration and oxygen concentration in air, and inversely proportional to the grain size of pulverized coal.
Different grain sized coal-dust have different ignition temperature.
A number of studies have suggested that test results of 20 L explosion devices is comparable to 1m3 standard volume explosive device, therefore, many countries tend to use 20 L explosive device to determine the pulverized coal Pmax and (dP/dt) max.
The influences of oxygen content in air, the concentration and grain size of pulverized coal can be shown by the formula .

In our present study, the activated carbon monoliths (ACMs) porous electrodes were prepared from self-adhesive carbon grains (SACG) based on our previously reported method [2,11–13].
FESEM micrographs show the presence of pores in the bare electrode (Fig. 1(a)), and less number of pores appear in Fig. 1(b) as some pores occupied by nanoparticles of nickel oxide.
A describes the characteristic of the electrode surface which depends on WR and WT; j (= √-1) is the imaginary number, ω is the angular frequency and n is the Warburg exponent equal to WP.
Harun, Young’s modulus of carbon from self-adhesive carbon grain of oil palm bunches, J.
Alias, Electrical and mechanical properties of carbon pellets from acid (HNO3) treated self-adhesive carbon grain from oil palm empty fruit bunch, J.

Table 1 The orthogonal experiment table of photoelectric properties of ITO thin films number factors Results sol concentration（mol/L） Al3+/Zn2+ concentration ratio pretreatment temperature (ºC) coating layers sheet resistance (Ω/□) transmittane (%) 1 0.5 2% 350 10 1316 87 2 0.5 3% 400 15 1268 85 3 0.5 4% 450 20 536 88 4 0.75 2% 400 20 699 82 5 0.75 3% 450 10 1241 80 6 0.75 4% 350 15 1327 86 7 1 2% 450 15 516 74 8 1 3% 350 20 1860 76 9 1 4% 400 10 1595 75 Ⅰ 3120 2531 4503 4152 sheet resistance Ⅱ 3267 4369 3562 3111 Ⅲ 3971 3458 2293 3095 K1 780 844 1501 1384 K2 817 1456 1187 1037 K3 1324 1153 764 1032 S 544 612 737 352 Ⅰ 260 243 249 242 transmittance Ⅱ 248 241 242 245 Ⅲ 225 249 242 246 K1 87 81 83 81 K2 83 80 81 82 K3 75 83 81 82 S 12 3 2 1 Note: The sol concentration was the concentration of Zn2+, the level settling velocity was 5 cm/min, dried at 100°C for 10 min, pretreatment time was 10 min, annealed at 550 °C for two hours for preparation of all AZO thin films.
In experiment 3, the corresponding film grain growth was more compact and uniform, the surface roughness was small, and the maximum height of contour was 116.78 nm.
But in experiment 5 (contours of maximum height for the 690.66 nm) and experiment 7 (the maximum height of the contour for the 526.68 nm) corresponded to the film, there were holes in surface and poor uniformity, the grain was larger, the surface roughness was poor.
At the same time, the coating layers is too little to compensate the various defects formed in the nucleation and grain growth process, resulting in uneven film surface.
The project number is KM201110017004.

Preferential segregation of boron at the austenite grain boundaries, leading to reduction of the grain boundary energy, and by that affecting phase transformation behavior, is widely accepted opinion in all hardening mechanism theories [3].
A number of studies investigate mechanical characterization parameters of borided layers on steels, but these are not directly comparable due to difference in characterization technique, boriding process parameters, as well as, the influence of the different alloying elements in the substrate material.
Thus, in order to maintain the contribution to uncertainty as low as possible, the number of test was increased.
Raabe, Segregation of boron at prior austenite grain boundaries in quenched martensitic steel studied by atom probe tomography, Scripta Materialia 96 (2015) 13-16

In this study the addition of Sn to the Ti-Mo-Nb system was carried out with variations in the number of Sn (0, 4 and 8% by weight) to determine the effect of Sn addition on the structure microstructure and mechanical properties of Ti-Mo-Nb-xSn alloys.
In Figure 2 (a-c) it is observed that the titanium phase β has an equiaxed grain shape.
OM a (0%Sn) Β grain boundary α SEM OM b (4% Sn) SEM OM c (8%Sn) SEM Fig. 2 Optical and electron micrograph of as cast Ti-6Mo-6Nb-xSn alloy, (a) Ti-6Mo-6Nb, (b) Ti-6Mo-6Nb-4Sn, and (c) Ti-6Mo-6Nb-8Sn Fig. 3 shows the value of the micro hardness of Vicker’s of the Ti-6Mo-6Nb-xSn alloy as a result of five melting processes with the arc re-melting furnace.
Acknowledgement The author gratefully acknowledge the Direktorat Riset dan Pengambdian Masyarakat Universitas Indonesia (DRPM UI) as PITTA grant number NKB-0047/UN2.R3.1/HKP.05.00/2019 for their financial support; Ministry of research, technology, and higher education of the Republic Indonesia for the master degree scholarship.
[15] Zhang Q, Chen J, Tan H, Lin X, Huang WD, Influence of solution treatment on microstructure evolution of TC21 titanium alloy with near equiaxed b grains fabricated by laser additive manufacture, Journal of Alloys and Compounds, 666 (2016) 380–386

Samples differ for fibre reinforcement ratio, textile layout and the number of textile layers, while the lime-based mortar matrix is the same for all specimens.
Moreover, the grains composing the mortar matrix bond to the fibre bundles only up to a certain depth, the extent of which depends on the size of grains which can pass through the space among filaments more or less easily in relation to their size.
Samples differ for fibre reinforcement ratio, textile layout and number of textile layers, while the lime-base mortar matrix is the same for all specimens.
Tensile tests were carried out on specimens identified though the label, B-TRM#-nn, where # denotes the composite type (1, 2) and -nn is the number of the specimen.