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This type of fuel cell uses ceramic components and offers a number of advantages compared to other fuel cell types, for example, the high operating temperature gives fast reaction kinetics that allows for internal or integrated fuel processing which makes it possible to use a wide range of fuels with a relatively simple and cost effective technical design, a very high electric efficiency can be obtained since the high quality waste heat can be used for micro-turbines, etc.
Still dielectric spectroscopy can supply very valuable information about for example ion transport, grain boundaries and defect-impurity association in these oxides.
(1) This procedure has to be applied with care since it involves the subtraction of two large numbers.
The detailed interpretation of these effects involves polarization at e.g. grain boundaries as well as bulk effects. 0 1 2 3 4 5 6 7 0 -1 -2 derivative log f (Hz) 497°C 399°C 276°C Figure 3.

Design of experiments has a major effect on the number of experiments needed.
Therefore, it is important to have a well-designed experiment to minimize the number of experiments.
BBD Cube Experimental Details End milling experiments were carried on V-30 CNC milling machine using 6mm two flute square end micro grain carbide end mill.
The best surface roughness value in dry cutting by using two flute micro grain solid carbide end mill is produced at cutting Condition (V=20000 rpm, f=1 mm/min) with a considerable sensitivity to the cutting speed and feed rate Acknowledgements The author’s great fully acknowledge the financial support of this research by Ministry of Science (Malaysia) under MOSTI grant to Curtin University.

The crack paths in all specimens are sinusoidal due to pullout of grains during propagation.
Micro-powder blasting (or micro-abrasive jet machining) is one of the mechanical material removal techniques, which uses fine-grained abrasive particle jet propelled by highly pressured gas.
From the figure, it can be observed that the erosion depth increases almost linearly as h-BN content increases at constant number of nozzle scanning times.
The drilling process is divided into a certain number of steps and a drill is fed into the composite repetitively until reach the desired depth.

It has been shown that the Mg-Al-Si based alloys are thought as a potential magnesium alloys with good high temperature properties, acceptance castability and low cost[1,3,4,5], because the silicon addition to magnesium alloys causes an increased fluidity of the molten metal, and the Mg2Si formed by the addition of Si exhibits high melting point, high hardness, low density, high elastic modulus and low thermal expansion coefficient, and the Mg2Si phase is very stable and can impede grain boundary sliding at elevated temperatures[3,6,7].
Experiment results and discussion 2.1 Effects of Al content on the as-cast microstructure The as-cast microstructure of permanent mould cast Mg-xA1-0.7Si based alloys with (6~8)%Al content are shown in Fig.1. it was found that the as-cast microstructure of Mg-xA1-0.7Si based alloys with (6~8)%Al content were mainly composed of white α-Mg matrix and black second phases, and these second phases mainly distributed on the grain boundaries, and with the increasing of Al content from 6% to 8%, the amount of the white α-Mg phase decreased, their distribution were more continuous and uniform.
Table 1 chemical composition of experimental alloys[wt,%] Alloy number Al Si Zn Mn Sb RE Mg No.1 6 0.7 1 0.25 0.4 0.25 bal No.2 7 0.7 1 0.25 0.4 0.25 bal No.3 8 0.7 1 0.25 0.4 0.25 bal (a) (b) A Fig.1 As-cast microstructure of Mg-xA1-0.7Si based alloys with different Al contents (a):No.1 alloy; (b):No.2 alloy; (c):No.3 alloy; (d):EDS spectrum from the area 'A' in (a) (c) keV (d) Elemen t Weight% Mg 66 0 100 200 300 400 500 20.000 40.000 60.000 80.000 2Theta [deg.]
Table.2 The mechanical properties of the as-cast Mg-(6~8)A1-0.7Si based alloys Room temperature 150℃ Alloy number UTS [MPa] YS [MPa] Elongation [%] UTS [MPa] YS [MPa] Elongation [%] No.1 175 99 5 170 94 16 No.2 197 104 7 182 90 21 No.3 176 112 5 172 69 14 3.

For aggregate of single dimension R, porosity in least close-grained state is 48% and porosity in most close-grained state is 26%.
According to fractal theory, N(R) indicates the particle number that bigger than R, and M(R) indicates the quality of particle that bigger than R.
Then, aggregate number with each dimension can be calculated according to their density.

However, the number of commercially available Mg alloys is still limited especially for application at elevated temperature.[1] The poor cold rolling response of Mg is generally attributed to its hexagonal crystallography and the basic symmetry of hexagonal close-packed (HCP) crystals has the effect of limiting the number of independent slip systems and making twinning an important deformation mechanism.
A quick examination by etching in a 10% NaOH solution occasionally revealed a few very small stray grains on the surface, but they were always removed from gauge section during machining process.
As a result of this, the way in which a particular crystal in a polycrystalline aggregate is strained may depend strongly on the orientation of the crystallographic axes of the grain with respect to the stress axes.

SEM micrograph Fig 2 .XRD graph The Brinell Hardness Number (BHN) and Density (g/cc) of the samples are depicted below in Fig.3 and 4 respectively for both conventionally and microwave sintered samples.
Fig. 3 Brinell Hardness Number Fig 4 Density (g/cc) The hardness and density values of the composites decrease with increase in cenospheres content which can be seen from Fig.3 and 4.
The reason may be attributed to the fact that as the grain/ filler size progressively increased beyond a certain level in samples M2 to M4 and C2 to C4, both the strength and the hardness decreased with increased porosity in the composite [6].
The SEM picture corroborates the slide wear data in terms of grain morphology.

The depletion of chromium from the austenite near grain boundaries due to chromium carbide precipitation and very unstable austenite were quite prone to martensite formation.
Low thermal conductivity of austenitic stainless steel tends to reduce the cooling rate and increasing austenite grain size.
Increasing grain size will accelerate precipitation and enhanced the diffusion rate of carbon.
Weld micrograph showed different grain sizes and orientations from the fusion line, including the heat-affected zone (HAZ), as seen in Fig 3.
Acknowledgments The authors would like to acknowledge the support of research funding from the Directorate of Research and Community Service of Universitas Indonesia through “Hibah Publikasi Internasional Terindeks 9 (PIT 9)” in 2019 with the contract number: NKB-0082/UN2.R3.1/HKP.05.00/2019.

To date, in Ukraine, the USA, India, Kazakhstan and a number of other countries, significant volumes of slag waste from the use of energy fuel oils have been accumulated in dumps.
Granulometric composition (%) of different ash types of ASW Grain size, [mm] Ash type Fine-grained ash with fragments of slag Fine-grained ash Dusty ash >0.63 22.8 1.4 0.4 0.2–0.63 28.4 7.6 1.7 <0.2 48.8 91 97.9 The identified varieties of ash reflect its granulometric sorting during hydraulic removal.
There are often observed yellowish-brown grains with Nm=1.645 probably represented by compounds of iron aluminosilicates.
The use of ASW in construction and other industries is constrained by a number of negative factors: 1.
[25] «Ukraine in numbers in 2020» statistical collection – Kiev: State Committee of Statistics of Ukraine, (2021)

The results of the analysis have been recorded in the form of micrographs and diagrams presenting the composition and the number of elements in the particular place of the samples thereof.
Sand grains coated by the C-S-H phase.
SiO2 grains became more solid and almost completely surrounded by the C-S-H, which was successively transferred into its other forms.