a gas-generating chamber at the bottom and a reaction chamber

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In this article, the products of reaction [1] will be characterized. New characterization methods such as X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and focused ion beam (FIB) sample preparation will be used against previous studies. The temperature and

In this article, the products of reaction [1] will be characterized. New characterization methods such as X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and focused ion beam (FIB) sample preparation will be used against previous studies. The temperature and pressure of the system will be compared to the equilibrium calculation. Finally, a formation mechanism is proposed.
experimental
This section reports the experimental procedure, based on the work of Broggi and Tangstad [18]. The particles are made of SiO2 and SiC powders in a molar ratio of 2:1. Table II shows the size distribution parameters d10, d50 and d90 of the two powders. These particles are used to produce gas mixtures with controlled composition. SiO2 is a commercial quartz called Quartz20, while SiC is available from Washington Mills. The powders were mixed for two hours and then granulated with water as a binder at room temperature. The final average diameter of the particles is between 1 and 2 mm.
The particles were dried at 110 °C (383 K) for 6 h and calcined at 1200 °C (1473 K) for 30 min. A 600 µm sized sieve separates the fine powder after calcination. The pellets were fed into a graphite tube furnace. Use 20 g of pellets per experiment. SiO2 and SiC particles yield sio compound name according to the reactions given below:
The graphite tube furnace is shown in Figure 1. Tube measures 265mm high and 150mm diameter. The tube is divided into two parts: a gas-generating chamber at the bottom and a reaction chamber mounted above. SiO2-SiC particles are placed in the crucible in the gas generation chamber. The reaction chamber has an inner diameter of 25 mm and a height of 150 mm. As shown in Figure 1, SiC particles with diameters between 3 and 6 mm filled the chamber up to 130 mm from the bottom. Their purpose is to act as a reactive substrate (Figure 2). Before heating the pellets, inject Ar(g) or He(g) as an inert gas to remove oxidizing elements from the air. Inert gas was passed through during the whole experiment. Alumina tubes are used to direct the inert gas to the bottom of the crucible. The alumina tube and SiC substrate are assumed to be inert to SiO(g) and CO(g) reactions in the temperature range present in the reaction chamber. The thermal history of the experiment was recorded by C-type thermocouples at different positions in the reaction chamber. The thermocouple does not move during the experiment. In each experiment of series 1 and 4, insert a C-type thermocouple at a fixed location. Thermocouples are shielded by alumina tubing.

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