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This research obtained the increase of hardness value and the number of pearlite and ferrite.
Sandpaper the sample surface with sandpaper size number 80, 120, 240, 400, 600, 1000, 1200 and 1500 (from coarse to fine).
The number of pearlite can be seen clearly in the austenite area which is at the phase (α + γ) with holding time as well as quenching and tempering treatment increases the pearlite volume.
The increase of hardness value occurred because the increase of pearlite volume fraction, this happened due to the austenite crystals are too large, so the rapid cooling pearlite will form parallel pearlite plate structure, which growns in coarse austenite crystal grains that will lower ductility/toughness of the steel.

These computational models would have great value in increasing the understanding of the cutting process and in reducing the number of experiments which traditionally are used for tool design, process selection, and machinability evaluation.
E [GPa] n [ - ] a [10-6/K] l [W/mK] cp r [N/m2K] 210 0.3 11 42 3.6 106 The Selected tools for this investigation were uncoated and fine-grain carbide (grain size 0.5-0.7mm) gundrills (d = 2.5, 8.0 mm, ISO HW-K15).
Summary To reduce the number of gun drilling tests required for tools optimization and to increase the understanding of the high performance machining process gun drilling, a uniform computational model has been developed by using the commercial implicit FE code Deform-3DTM.

Gao et al. [4] performed the high-speed weld of ultra-fine grained steel by using this technique.
These parameters can be described by the following equations: （2） （3） According to Rosenthal equation, the temperature T at any location within the plate can be described by the following equation: （4） here Pabs represents the laser power absorbed by the material; δ is the thickness of the plate; k is the heat conduction coefficient; α is thermal diffusion coefficient and ; T0 represents the original temperature of workpiece; K0 is the second kind Bessel function in a modified form; Pe represents the Peclet number.
Finally the energy effectively absorbed by the workpiece can be calculated by: （5） here n is the total number of the slices.
Laser-TIG hybrid welding of ultra-fine grained steel.

Before aging a dense network of dislocations is observed inside the grains.
These dislocations are arranged in cells and many grains are heavily twinned as shown in Fig. 2b.
There is no increase in the number or size of dislocation cells, as shown by the index (i).
Table 2: Characterizations of TiC nano-precipitates for each aging heat treatment   number of counted precipitates Mean spherical diameter (nm) Mean density r (m-3) Volumic fraction (%) 650°C – 100h [4] - 6 - ≈ 0.4 600°C – 500 h [11] 97 4.3 ± 1,7 4 ± 2 x 1022 - 600°C – 1000h (our measurements) 921 4.3 ± 1,6 2.1 ± 0,5 x 1022  0.095 550°C – 1000h (our measurements) 680 3.0 ± 0,9 1.7 ± 0,5 x 1022  0.030 500°C – 4775h (our measurements) 64 2.4 ± 0,5 6.3 ± 2 x 1021  0.0046 Effect of aging on tensile behaviour Figure 4 compares the engineering stress-strain curves obtained at 20°C from tensile tests on tubes that were aged for 1000 hours at 400, 500, 550 and 600°C.

The slurry mixture obtained then carried out a viscosity test with digital viscometer NDJ 8S using rotor number 2 and rotor speed of 30 rpm.
In addition, it appears that irregular grain shapes with small size.
However, irregular grain shape with a wide particle size distribution is advantageous because it can provide an interlocking effect that can make the coating layer dense and evenly distributed[11]. 40µm 40µm 40µm c b a 40µm 40µm 40µm f e d Figure 4.
Acknowledgement This research is conducted under research grant by Directorate of Research and Community Service University of Indonesia “Hibah Publikasi Internasional Terindeks untuk Tugas Akhir” with agreement number NKB-0721/UN.R3.1/HKP.05.00/2019 References [1] U.

The issue of the urban environment decoration, which is the residence place for a considerable number of people who seek aesthetic pleasure, has continuously been the task of urban architecture authority and it is quite successfully performed [1-4].
Properties of the soil taken for research Grain size composition/distribution, % Grain size, mm 2-1 1-0.5 0.5-0.25 0.25-0.071 <0.071 0.4 1.6 32.8 60.2 5 Liquidity limit, % 7.5 Optimal humidity at maximum density, % 7 Maximum density at optimal humidity, g/cm3 2.148 Table 2.
The approach applied to the experiment enables the use of mathematical planning to accelerate the time of its implementation and reduce the number of samples without losing the intermediary results and with sufficient statistical evidence.

PLGA grains (LA/GA=70/30, Mw=7.31×105, Mn=3.19×105, PI=2.29) were provided by Institute of Chemistry, Chinese Academy of Sciences.
PLGA grains were thoroughly dissolved in 1,4-dioxane.
Acknowledgements We would like to thank the Hi-tech Research and Development Program of China for supporting this work under grant number 715-009-0160.
This work is also supported by the National Natural Science Funds of China under grant number 30300356, 50577067.

Because of air pollution, the patients with lung cancer has increased 45.6% in China in the past 30 years, but the number of smokers has not significantly increased according to authoritative statistics.
The second particles of PM2.5 can be produced (gas →grain) by chemical multiphase reactions, such as tiny particles transformed by ordinary gaseous pollutants.
Coagulating Technology to Remove Ultra-fine Dusts The coagulation will agglutinate ultra-fine particles together to form larger grains so as to be captured by a dust-removal equipment.
(in 2004) carried out a research on the dust charged by corona between two plates and the coagulation in an alternating electric field (160 -500Hz) between two plates, and the results show that the number of particles less than 1μm decreased by 25- 29 % [5].

The range of chemical composition of Portland cement is shown in Table 1, which lists the minimum, average and maximum values for a large number of samples analysed [1].
Chemical analysis data [1] on major and minor constituents of Portland cements (wt%) Component Minimum Average Maximum Samples Average (100%) CaO 58.1 64.18 68.0 284 67.06 SiO2 18.4 21.02 24.5 284 21.96 Al2O3 3.1 5.04 7.6 284 5.27 Fe2O3 0.16 2.85 5.8 284 2.98 MgO 0.02 1.67 7.1 284 1.75 K2O 0.04 0.70 1.7 280 0.73 Na2O 0 0.24 0.8 263 0.25 SO3 0 2.58 5.35 280 - Free lime 0.03 1.24 3.68 132 - Total 99.52 100 The main composition studied was based on a maximum number of 7-components (i.e.
The C/S ratio of an interstitial glassy phase reported by [4] was reduced from 6.55 to 5.08, and microstructural investigations showed that C2S grains started to dissociate and leave a dendritic skeleton behind. 0 10 20 30 40 50 60 70 80800 1000 1200 1400 1600 1800 Temperature (οC) Mass (%) 7 Comp. 5 Comp 4 Comp b 0 10 20 30 40 50 60 70 80800 1000 1200 1400 1600 1800 Temperature (C) Mass (%) 7 Comp 5 Comp. 4 Comp a 0 10 20 30 40 50 60 70 80 1450 1350 1250 1150 1050 950 Temperature (°C) Mass (%) C3S Liq C2F KC23S12 C3AC2S is usually observed as the β-polymorph in Portland cement clinkers not as the γ-polymorph, typically containing 4-6% of other oxides [3].
K2O released deposits in the grain boundary or in the intra-crystal cracks within the αC2S, as documented by Chan et al. [5] who reported that the final K2O content could be a maximum of around 1.2% in α-C2S, which on further cooling converted to β-C2S stabilised by the presence of the K2O.

Antibacterial properties: The Escherichia coli were used to investigate the antibacterial properties, the number of bacteria was obtained by the method of enumeration tests.
Table 1 Thermal Stability of Cu-Antibacterial White Carbon Black Modified by Surfactant Test item Temperatures(oC) 400 500 600 700 800 900 1000 Appearance color white white white white white white white Average grain diameter(μm) 5 5 5 5 5 5 5 Bacteriostasis rate(%) 98 98 97 98 98 98 97 Analysis of Light Stability.
Table 2 Light Stability of Cu-Antibacterial White Carbon Black Modified by Surfactant Test item Light source Sunshine Fluorescent light Appearance color white white Average grain diameter(μm) 5 5 Bacteriostasis rate(%) 98 98 Therefore, the Cu-antibacterial White Carbon Black modified by surfactant, which has good thermal and light stability, is appropriate to be added to materials and made antibacterial product.
The antibacterial experiment is performed by calculating the number of bacteria.