Phototime in x ray a technique5/3/2023 The obtained analysis confirms that the annealed SS absorber exhibits excellent selectivity and is suitable to withstand any thermal condition (≤700 ☌) in air. These results indicate a small improvement in absorptivity (0.941) and emissivity (0.403) after annealing at 300 ☌, followed by a significant decrease after annealing at 700 ☌. The as-treated SS absorbers exhibit a good spectra selectivity of 0.938/0.431 = 2.176, which compares with 0.941/0.403 = 2.335 after being annealed at 300 ☌ and 0.884/0.179 = 4.939 after being annealed at 700 ☌. The strain (ε) and stress (σ) calculated for the as-treated absorber are 1.2 × 10 −1 and −2.9 GPa, whereas the annealed absorbers are found in the range of 4.4 × 10 −1 to 5.2 × 10 −1 and −121.6 to −103.2 GPa, respectively, at 300–700 ☌. The EDS result shows that the elemental components of the SS were C, Cr, Fe, and O. The phase of the as-treated and annealed SS was further identified by XRD as Fe 2O 3. The XRD analysis shows that the grain size of the as-treated absorber is 67 nm, whereas those of the annealed absorbers were found to be in the range between 66 and 38 nm. Therefore, the SS was characterized by X-ray diffraction (XRD), mechanical, and optical techniques. Thermal stability testing in the presence of air is critical if the vacuum is breached. In this case, the lens is scanned for different energies.In this work, we study the thermal stability of a hydrothermally treated stainless steel (SS) selective solar absorber by annealing in air in a temperature range between 300 ☌ and 700 ☌ for a soaking time of 2 h. For this to occur, the analyzer is also arranged so that only photoelectrons of a specific, fixed kinetic energy will pass through and reach the detector. In FAT mode, the lens either retards or accelerates the electrons so that all photoelectrons enter the analyzer with the same kinetic energy. These analyzers are also capable of running in two separate modes when coupled with an optical system - fixed analyzer transmission mode (FAT) and fixed retardation energy mode (FRR). The resolving power of these analyzers is proportional to the radius of the inner and outer hemispheres. Here, the potential is different for both the inner and the outer hemisphere: Only photoelectrons of the correct energy are able to pass through the detector with the right arc and exit instead of colliding with the side walls of the hemispheres and becoming lost. Since SDAs are the most common, prevalent type of PES analyzer, they will be discussed in more depth than any of the previous analyzers as a thorough understanding of how they apply to PES is, theoretically, of greater importance. In an SDA, the transmission of photoelectrons with initial energy, E 0, occurs along a path where R 0=(R in/R out)/2. SDAs are similar to CDAs, but they consist of two concentric hemispheres instead. These lenses are also capable of focusing on a small area of a particular sample. The design of any lens system greatly effects the photoelectron counts. Optics are also capable of accelerating the electrons as well. The energy the photoelectrons decelerate to is known as the "pass energy." This has the benefit of significantly raising the resolution, however this does, unfortunately, lower the sensitivity. Electron optics are capable of decelerating the photoelectrons through retardation of the electric field. In order to actually get well resolved, useful data other components must be introduced into the instrument.Īdding a system of optics (lenses) to a PES instrument helps with this problem immensely. The faster the electrons are moving, the lower the resolution and intensity is. The intensity of the spectra produced is also dependent on the kinetic energy. \), the resolution is directly dependent on the kinetic energy of the photoelectrons.
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