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The effects of Y addition up to 5.13% (in weight) to Mg-Zn-Zr alloys on oxidation behaviors under atmospheric ambient conditions were investigated in this study. Samples were heated in the ambient atmosphere at 400°C, with samples cooled to room temperature for mass measurement after some period time of cumulative exposure to obtain kinetic curves. XRD is used to analyze the mixture of oxides. Scanning electron microscopy combined with energy dispersive spectroscopy was used to study the scale microstructure and to obtain composition-depth profiles through the oxide layers. The oxidation results show that the weight gains for the alloys containing low Y concentration are obvious. The oxide films are thick and porous on the alloys containing low Y and thin and protective on alloys containing relatively high Y concentration. The addition of Y into Mg-Zn-Zr alloys results in the formation of protective film which is resistant to oxidation.

Cerium mononitride (CeN) film was fabricated by dual ion beam sputtering deposition method on silicon wafer. The oxidization process of CeN film was monitored by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. The results showed that, when the CeN film was exposed to ambient atmosphere, bubbles appeared on the film surface rapidly and then the surface flaked off to powders. Meanwhile, the CeN film changed from polycrystalline to amorphous. XPS analysis indicated that the CeN was oxidized to Ce₂O₃ initially, and then further oxidized to CeO₂. These results indicated that the CeN film degraded easily in ambient atmosphere, exhibiting little or no passivation.

A series of (Fe${}_{2.2}$Mn${}_{0.8}$Cu${}_x{)}_{1-\delta }$O₄ ($x=0$, 0.2, 0.5, and 0.8) was synthesized for elemental mercury capture. The as-synthesized adsorbents were characterized by Brunauer–Emmett–Teller (BET), powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The experimental results show that (Fe${}_{2.2}$Mn${}_{0.8}$Cu${}_{0.5}{)}_{1-\delta }$O₄ catalyst adsorbent exhibits the best elemental mercury capture capacity with the increase in mercury removal efficiency by 20% as compared to the (Fe${}_{2.2}$Mn${}_{0.8}{)}_{1-\delta }$O₄ adsorbent. The XPS results indicate Cu dopant can provide the lattice oxygen on the adsorbent surface due to the transformation from Cu${}^{2+}$ cations to Cu${}^{+}$ cations, which increases the active sites for elemental mercury adsorption. The Mn${}^{4+}$ cations on the adsorbent surface may oxidize the adsorbed mercury to mercury oxidization. Meanwhile, the Mn${}^{3+}$ cations formed are also oxidized to the Mn${}^{4+}$ cations by the gaseous oxygen phase in the reactor gas. However, the large Cu content may block the collision between Mn${}^{4+}$ cations and adsorbed mercury, and thus decrease the oxidization capability of adsorbent surface for mercury. Therefore, the Cu dopant with the suitable content may be a potential modified method for the adsorbent to further increase the elemental mercury capture.

One of the most commonly used techniques for purification and eventual dispersion of single-wall carbon nanotubes (SWNTs) is oxidation using strong acid and ultrasonication. Literature review reveals that ultrasonication of varying radiation intensities have been used during the acid oxidation, but few have reported whether ultrasonication of different intensities would have different effects on the structure and properties of SWNTs and how the effects are. An investigation of the effects of ultrasonic radiation intensity on SWNTs during oxidation in a mixture of sulfuric and nitric acids was conducted. Ultrasonication using different intensities (50 W, 100 W, 200 W and 300 W) was used. The acid-treated SWNTs were characterized by scanning and transmission electron microscopy, Fourier transform infrared spectroscopy, zeta potential test Boehm titration test and Raman spectrum analysis. Data from these experiments showed that high intensities provided stronger oxidizing conditions than lower ones. As ultrasonic intensity increased, larger number of SWNTs were destroyed and consumed to produce carbonaceous impurities, and more defects appeared in the tube walls.