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The service life of a refractory depends on a number of factors that include ash chemistry and quantity (percent), the amount of carbon feedstock throughput, the amount of gasifier cycling between room and operational temperature, gasifier maintenance, and the quality and performance of the refractory liner.
Historically, a number of refractory compositions were considered or evaluated for slagging gasifier environments using coal or petcoke feedstock before current liner materials were selected.
The practice of carbon treatment has evolved into mixing refractory grains and powders (including anti-oxidants) with a phenolic resin or other high carbon content binder, pressing the piece into a shape, curing the shape, than coking it to convert the resin to carbon.
The use of prefired shapes (with a ceramic bond between grains) treated with pitch or coal tar is not commonly practiced today due to the shift in technology to other bonding techniques such as resin in the refractory materials that form a carbon bond between refractory grains.
The goal of carbon in the porous structure of gasification refractories is to limit the penetration of slag into the porous structure of the refractory material and reduce slag corrosion of oxide grain into the slag.

Larger grains formed with higher substrate temperatures result in irregular surface features which can importantly change the electrode geometry [39].
Masks composed of carbon nanotubes provide a highly controlled and scalable technique for generating number of nano junctions [39].
Numbers of nano junction with separations distance of 0.8–2.3 nm are possible using the smaller single-walled nanotubes [39, 40] with device production in excess of 80%.
However, the surface defects and grain boundaries in the electrodes causes an uneven accumulation of metal on the surface [36].
Most significantly, numbers of junctions with consistent and reproducible electronic characteristics are now possible.

The fitting line could not follow well with the observed data in the higher oxygen partial pressure region, because the number of oxygen is higher than 3 in the higher oxygen partial pressure region (Fig.3(b)).
The diffusion profile in one section is calculated by the following equation: where, Cn(x) is the concentration of 18O at x in the section number of n [ 1≤n≤100, 5×(n-1)≤ x /nm ≤5×n ] and Cn-1 indicates the 18O concentration at the boundary of next before section (section n-1).
Dn* is the calculated diffusion coefficient of isotope oxygen at the section number of n in the LaMnO3 film, and t is the 16O/18O exchange duration time (t=300 s).
In air atmospheres, a number of authors have reported the oxidation of alloy and the formation of oxide scales.
With respect to the factor (iii), small and thin grain boundary in oxide scales can affect the diffusion of oxygen, although we could not observe the grain boundary diffusion in the oxide scales by SIMS imaging due to small grain size of oxides (grain boundary side is presumably on the order of 1 µm in width). 4.

This paper conducted a research on theory of extrusion pressure when powder of pure UHMWPE resin is still in feeding section by molding in barrel of the single screw extruder specially designed for pure UHMWPE, and established a n-lamina model of powder materials or grain materials which is in feeding section and at the state of non-plug flow solid conveying, and it provided a method to calculate extrusion pressure of the n-lamina model, thus it enriched and perfected theory of single-screw extrusion molding.
The method of numbering lamina is as follow: Lamina 0 is the screw (screw is stationary, its speed is), Lamina m + 1 is the barrel (barrel is rotating, its speed is), Lamina 1 contacts with the screw directly, Lamina m contacts with the barrel directly; let the serial numbers of other laminae of materials be numbered from 2 to m-1 in +Y direction along Y-axis[3].
Fig.1 m-lamina physical model of non-plug flow solid conveying in feeding section by single-screw extrusion molding Fig.2 materials of any lamina i and materials of its neighboring upper and lower lamina Mathematical model Basic Assumptions The main basic assumptions are as follows[1,3]: (1) Solid conveying process is stable, the screw remains stationary while the barrel makes a reverse rotation, screw curvature is neglected; (2) Gravity, inertial force, and internal elastic deformation energy of materials are neglected; (3) Materials in screw groove is separated into a lot of thin laminae, the total number of which is n, each lamina represents a solid plug (Let n and m be positive integers, n is the total number of the laminae of materials, and can be an arbitrary positive integer, m represents a fixed value of n, namely the total number of laminae n=m); (4) When analyzing pressure, let each cross-section of the lamina of materials bear stress evenly, and coefficient of side pressure
The solution for n-lamina model of non-plug flow solid conveying in feeding section by single-screw extrusion molding (Establishment of the fundamental equations when total number of laminae of materials n=m) In equation (3), parameter i may take different values, and friction coefficients between any lamina of materials and its neighboring lamina should be considered, then the following fundamental equations can be gotten (when total number of laminiae n=m) (4) (5) (6) In the above equation: 1） ; 2） is defined by formula (7), let be an increase trend of compressive stress; 3）the following parameters are assumed: , , ,,,
Summarize (1) As to n-lamina model of non-plug flow which is established in this article, when the total number of laminae of materials equals 3, m=3, the formula of extrusion pressure is completely consistent with the pressure formula of “Trilamina method of non-plug solid conveying” [2].

The microstructures show the epitaxial development of larger columnar grains.
The characteristic microstructure of components produced through WAAM generally exhibits large columnar grains, resulting from repeated cycles of melting and solidification during the process.
The cooling rate plays a key role in the microstructure and mechanical properties of WAAM products, and the addition of argon, CO2, nitrogen, or forced water cooling can improve grain refinement [66].
This research was also partly supported by EU ERASMUS+ Strategic Partnership Key Action 2, number: 2021-1-RO01-KA220-VET-000028028 (DIGIGREEN), ERASMUS+ Strategic Partnership Key Action 2, number: 2023-1-RO01-KA220-HED-000158031 (ANGIE).
Kennedy, Effect of Machine Hammer Peening Conditions on β Grain Refinement of Additively Manufactured Ti-6Al-4V, Metals (Basel) 13 (2023). https://doi.org/10.3390/met13111888

Characteristics of high performance concrete in the configuration is the low water binder ratio,the selection of high quality raw materials,and must be mixed with a sufficient number of admixture (fine mineral admixture) and high efficient additives[3].
High performance concrete, therefore, must have a high fluidity but no segregation and no bleeding, easy to shape, easy to close-grained, hydration hardening of early settlement shrinkage and hydration of narrow, low temperature, dry shrink hardening process.
(railway concrete design use fixed number of year 100, the C50 and over electric flux is not more than 1000 coulomb, C20～C25 electric flux is not more than 2000 coulomb, C30～C45 electric flux is not more than 1500 coulomb. 56 different water-binder ratio of C50 concrete stray flux test results listed in table 4.
Table 4 C50 56 day concrete electric flux value Serial number Water/cement ratio Dentsu quantity/coulomb 1 0.28 465 2 0.29 560 3 0.30 650 4 0.31 845 5 0.32 960 6 0.33 1235 From the table 4 shows that C50 high performance concrete is higher than the water-binder ratio of 0.33 the durability performance is affected.
High performance concrete to be mixed with a sufficient number of mineral admixtures and high-performance admixtures.

Ca/Eu co-doped α-SiAlON powders had hollow sphere morphology and it is composed of large numbers of very fine particles of around 30 to 70 nm in diameter.
Apparently, the luminescent intensity increased with the increase of the holding time, this was possibly caused by the enhanced grain crystallinity and the decline of defect in the powder.
It was found that the synthesized Ca/Eu co-doped α-SiAlON powders had a beadlike texture (Fig. 3), the SiAlON beads were actually hollow spheres and composed of large numbers of very fine particles of around 30 to 70 nm in diameter, which could be detected by the higher resolusion TEM Image (Fig. 4).
The beads were actually hollow spheres and composed of large numbers of very fine particles of around 30 to 70 nm in diameter.

A growing number of researches believe that Dry Centrifugal Granulation (DCG) process is the most promising process in deal with the molten slag to raw material in cement produced on account of the no water consumes no harmful gas emissions and efficient recovery of waste heat.
Mathematical Model and Boundary Conditions General Assumptions For centrifugal graining process, plan as shown in figure 4, intermediate buffer is at the top; the center-aligning rotating cup is right below the slag drop pipe.

Oxidation can result in several adverse conditions: general section loss from material thinning, deep and localized section loss from internal oxidation along grain boundaries, dimensional changes that are critical in airfoils, and downstream erosion from oxide spallation.
In addition, oxidation may modify creep behavior (beyond mere section loss) by its near-surface effects on grain boundary morphologies and precipitation strengthening.
The microstructures shown in Figs. 1-4 show that internal oxidation of aluminum has occurred beneath the oxide scale and predominantly along grain boundaries
-0.3 -0.1 0.1 0.3 0.5 0 500 1000 1500 2000 Number of Cycles (Hours) 37% H2O-Air 760C Inconel 718 Inconel 718 x4 300 Cycles300 Cycles 2000 Cycles 2000 Cycles Fig. 3.
Equation 4 is valid for Sc numbers between 0.6 and 50 [6].

Surface roughness can also been caused by parallel crystals and depends also on the grain size.
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