Journal articles: 'Magnesium oxide Magnesium oxide Oxides. Semiconductors'

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Roshchin, V. E., P. A. Gamov, A. V. Roshchin, and S. P. Salikhov. "ELECTRON THEORY OF METALS REDUCTION: THEORY AND METHODS OF METALS EXTRACTION FROM VARIOUS TYPES OF ORE." Izvestiya. Ferrous Metallurgy 62, no. 5 (June 19, 2019): 407–17. http://dx.doi.org/10.17073/0368-0797-2019-5-407-417.

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The present work analyzes the existing mechanism of solid-phase metals reduction from oxides. It was shown that the existed mechanisms of reduction do not explain the diversity of the practical results leading to a generally accepted opinion that there is no single uniform reduction mechanism. This study presents the results of the solid-phase reduction of metals from lump magnetite, siderite, titanomagnetite and chromite types of ore by carbon from various deposits. The obtained results were compared with the results of reduction of chromium, silicon and aluminum by carbon from pure oxides. Change in the electrical characteristics and analysis of the processes of electron- and mass transfer under reducing conditions were performed to clarify the general theoretical concepts of reduction mechanism. It has been concluded that there is general process of transformation of the crystal lattice of oxide into the crystal lattice of metal for reduction of different metals. The positions of electron theory for solid-phase reduction of metals from crystal lattice of oxides were developed using the basic concepts of chemistry, solid state physics about imperfect crystals, quantum mechanics and character of electron distribution and transfer in metals and ionic semiconductors. The theory embraces all the known results of reduction with formation of metal on the surface of high-grade lump ore, nucleation of metal inside of the complex and low-grade types of ore and formation and sublimation of suboxides. Major ideas of the developing theory of electron reduction have been formulated on the basis of metals reduction as a result of the exchange of electrons between the reducing agent and metal cations in oxides by means of the charged anion vacancies formed on the surface and their scattering in the volume. The transformation of the cations’ ionic bond in oxides into metallic bond of the metal phase on the surface (or inside of the oxide lattice) occurs without the displacement of the cations over significant distances and thermodynamic difficulties for the formation of metallic nucleus when the charged anion vacancies merge (skipping the stage of formation of the atoms of metal). There might be no direct contact between the metal and the reducing agent in case of formation of the metal phase inside of the oxide volume. As a result, harmful impurities from the reducing agent, e.g. carbon and sulphur, do not penetrate into iron during reduction of complex and low-grade types of ore. Therefore, for the reduction of iron from such an ore, it is possible to utilize a low-quality reducing agent, e.g. steam coal. The selective solid-phase reduction of iron from lump complex ore makes it possible to obtain a metal-oxide composite material containing pure DRI and valuable oxides which are difficult for reduction, i.e. oxides of magnesium, titanium and vanadium.

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Nemade, K. R., and S. A. Waghuley. "Synthesis of MgO Nanoparticles by Solvent Mixed Spray Pyrolysis Technique for Optical Investigation." International Journal of Metals 2014 (April 14, 2014): 1–4. http://dx.doi.org/10.1155/2014/389416.

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Solvent mixed spray pyrolysis technique has attracted a global interest in the synthesis of nanomaterials since reactions can be run in liquid state without further heating. Magnesium oxide (MgO) is a category of the practical semiconductor metal oxides, which is extensively used as catalyst and optical material. In the present study, MgO nanoparticles were successfully synthesized using a solvent mixed spray pyrolysis. The X-ray diffraction pattern confirmed the formation of MgO phase with an excellent crystalline structure. Debye-Scherrer equation is used for the determination of particle size, which was found to be 9.2 nm. Tunneling electron microscope analysis indicated that the as-synthesized particles are nanoparticles with an average particle size of 9 nm. Meanwhile, the ultraviolet-visible spectroscopy of the resulting product was evaluated to study its optical property via measurement of the band gap energy value.

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Anuradha, B., and C. Sanjeeviraja. "Review on Magnesium Indium Oxide Thin Films: Material Properties and Preparation Techniques." Materials Science Forum 699 (September 2011): 39–66. http://dx.doi.org/10.4028/www.scientific.net/msf.699.39.

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Thin films of pure metals, alloys, semiconductors and organic compounds are indispensable tools in industry, which anticipate and recognize novel functional materials for the development of microelectronics. Thin film technology makes it possible to deposit ultra-thin functional material layers on a base substrate to form many active and passive micro-miniaturized components and devices such as solar cells, radiation sources, sensors, magnetic devices, bolometers, switching devices, photodiodes, digital versatile disk (DVD), flat panel display etc. Thus thin films play a dominant role in modern technology like opto-electronics, microelectronics etc. The study of surfaces and thin films overlaying them has been carried out for many years. But recently, it has become increasingly important in several fields of study. Thin film properties such as optical, electrical and magnetic properties are very much interested in research areas. Thin film properties are strong dependent on the method of deposition, the substrate materials, the substrate temperature, the rate of deposition, the background pressure etc. Specific application in modern technology demand tailor made film properties, for example, high optical reflection / transmission, hardness. adhesion, nonporosity, high mobility of charge carriers / insulating properties and chemical inertness, which are possible with a selection of suitable functional materials and deposition techniques. Various techniques used to deposit thin films and the material properties of MIO and its crystal structure are summarized with our results.

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Ohsawa, Takeo, Yutaka Adachi, Isao Sakaguchi, Kenji Matsumoto, Hajime Haneda, Shigenori Ueda, Hideki Yoshikawa, Keisuke Kobayashi, and Naoki Ohashi. "Electronic States in Zinc Magnesium Oxide Alloy Semiconductors: Hard X-ray Photoemission Spectroscopy and Density Functional Theory Calculations." Chemistry of Materials 21, no. 1 (January 13, 2009): 144–50. http://dx.doi.org/10.1021/cm802467n.

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Nakamura, Tomoyuki, Kazuya Hatakeyama, Masahiro Minowa, Youhiko Mito, Koya Arai, Tsutomu Iida, and Keishi Nishio. "Power generation performance of π-structure thermoelectric device using NaCo2O4 and Mg2Si elements." MRS Proceedings 1490 (2013): 185–90. http://dx.doi.org/10.1557/opl.2013.53.

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ABSTRACTThermoelectric power generation has been attracting attention as a technology for waste heat utilization in which thermal energy is directly converted into electric energy. It is well known that layered cobalt oxide compounds such as NaCo2O4 and Ca3Co4O9 have high thermoelectric properties in p-type oxide semiconductors. However, in most cases, the thermoelectric properties in n-type oxide materials are not as high. Therefore, n-type magnesium silicide (Mg2Si) has been studied as an alternative due to its non-toxicity, environmental friendliness, lightweight property, and comparative abundance compared with other TE systems. In this study, we fabricated π-structure thermoelectric power generation devices using p-type NaCo2O4 elements and n-type Mg2Si elements. The p- and n-type sintering bodies were fabricated by spark plasma sintering (SPS). To reduce the resistance at the interface between elements and electrodes, we processed the surface of the elements before fabricating the devices. The end face of a Mg2Si element was covered with Ni by SPS and that of a NaCo2O4 element was coated with Ag by silver paste and soldering.The thermoelectric device consisted of 18 pairs of p-type and n-type legs connected with Ag electrodes. The cross-sectional and thickness dimensions of the p-type elements were 3.0 mm × 5.0 mm × 7.6 mm (t) and those of the n-type elements were 3.0 mm × 3.0 mm × 7.6 mm (t). The open circuit voltage was 1.9 V and the maximum output power was 1.4 W at a heat source temperature of 873 K and a cooling water temperature of 283 K in air.

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K, Rathidevi, Velmani N, and Tamilselvi D. "Electrical conductivity study of poly(p-anisidine) doped and undoped ZnO nanocomposite." Mediterranean Journal of Chemistry 9, no. 5 (December 14, 2019): 403–10. http://dx.doi.org/10.13171/mjc01912071050kr.

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Polymeric blends of Poly (p-anisidine) with ZnO nanoparticles was prepared by chemical oxidative polymerization. Zinc oxide doped PPA polymer nanocomposite (ZPPA) and Magnesium doped Zinc oxide PPA polymer nanocomposite (MZPPA) were synthesized with the addition of semiconductor metal oxide to the polymeric solution. The X-ray diffraction studies of ZnO nanoparticles showed hexagonal wurzite structure. The surface morphological study also confirms the formation of hexagonal structured nanoparticles. The peak for Magnesium and Zinc in EDS spectra confirms the formation of Magnesium doped polymer nanocomposite. The addition of ZnO/MgZnO onto PPA conducting polymer showed agglomeration of semiconductor material results in spherical shaped polymer nanocomposite and irregular overlapping over the PPA polymeric surface. The electrochemical conductivity studies suggested that the doped PPA conducting polymeric blends showed enhanced conductivity nature.

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El-Gamal, S., and Adel M. El Sayed. "Physical properties of the organic polymeric blend (PVA/PAM) modified with MgO nanofillers." Journal of Composite Materials 53, no. 20 (April 2019): 2831–47. http://dx.doi.org/10.1177/0021998319840802.

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Magnesium oxide/polyvinyl alcohol/polyacrylamide (MgO/PVA/PAM) nanocomposite films were prepared via a solution chemical method. The effect of PVA and MgO nanoparticles (NPs) loading on the physical properties of PAM is discussed. X-ray diffraction reveals that the average MgO crystallite size of the NPs is ∼25 nm, while adding PVA increases the crystallinity of PAM. FTIR spectra confirm the interaction between blend chains and MgO NPs. Differential scanning calorimetry thermograms illustrate the miscibility between the PVA and the PAM. The melting temperature, the glass transition, as well as the equilibrium swelling ratio, depend on the films' composition. PAM showed a transmittance of 87%, that increased to 90% after PVA addition, but decreased to 74% after MgO loading. Meaningful changes are observed in the extinction coefficient and indirect/direct band gap of PAM due to PVA blending and MgO addition. The influence of MgO NPs on the dielectric constant ( ɛ′) of the blend film is reported. The maximum value of AC conductivity of the blend is 4.77 × 10−3 Sm−1, which increased to 8.07 × 10−3 Sm−1 by increasing the MgO loading to 5.0 wt.%. The conduction mechanism changed from the correlated barrier hopping, in the blend, to the large Polaron tunneling with MgO loading. The observed improvements in optical properties and AC conductivity encourage the use of these nanocomposite films in the semiconductors industry.

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Hsiao, Chu-Yun, Chuan-Feng Shih, Chih-Hua Chien, and Cheng-Liang Huang. "Textured Magnesium Titanate as Gate Oxide for GaN-Based Metal-Oxide-Semiconductor Capacitor." Journal of the American Ceramic Society 94, no. 4 (March 4, 2011): 1005–7. http://dx.doi.org/10.1111/j.1551-2916.2011.04439.x.

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Guzmán, Manuel, Berta Vega, Núria Agulló, Ulrich Giese, and Salvador Borrós. "ZINC OXIDE VERSUS MAGNESIUM OXIDE REVISITED. PART 1." Rubber Chemistry and Technology 85, no. 1 (March 1, 2012): 38–55. http://dx.doi.org/10.5254/1.3672428.

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Abstract Zinc oxide is a widely used compound in the rubber industry due to the excellent properties that it shows as activator, and consequently, its role in the mechanism of accelerated sulfur vulcanization has been extensively studied. Due to the increased concern about its environmental effects, several research studies have been carried out in order to substitute it with different metal oxides such us MgO. The effect of the activator system in order to minimize the environmental impact of the rubber goods has been explored. The work developed is presented in two parts. In Part 1, the influence of different mixtures of ZnO and MgO on the vulcanization of natural rubber has been investigated. In Part 2, model compound vulcanization has been used to study the role of MgO on the mechanism to gain a better understanding of the differences shown in Part 1.

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Guzmán, Manuel, Berta Vega, Núria Agulló, and Salvador Borrós. "ZINC OXIDE VERSUS MAGNESIUM OXIDE REVISITED. PART 2." Rubber Chemistry and Technology 85, no. 1 (March 1, 2012): 56–67. http://dx.doi.org/10.5254/1.3672429.

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Abstract Zinc oxide is a widely used compound in the rubber industry due to the excellent properties that it shows as an activator and, consequently, its role in the mechanism of accelerated sulfur vulcanization has been extensively studied. Due to the increased concern about its environmental effects, several research studies have been carried out in order to substitute it with different metal oxides such us MgO. The effect of the activator system in order to minimize the environmental impact of the rubber goods has been explored. The work developed is presented in two parts. In Part 1, the influence of different mixtures of ZnO and MgO in the vulcanization of natural rubber has been investigated. In Part 2 of the study, model compound vulcanization has been used to study the role of MgO on the mechanism to gain a better understanding of the differences shown in the first part.

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Skomorovskaya, L. A., V. B. Zlatkovskii, and I. I. Nemets. "Interaction between magnesium oxide and rare-earth oxides." Glass and Ceramics 47, no. 2 (February 1990): 53–57. http://dx.doi.org/10.1007/bf00682605.

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12

Kim, Yo-Han, Vu Anh Tuan, Myung-Kyu Park, and Chang-Ha Lee. "Sulfur removal from municipal gas using magnesium oxides and a magnesium oxide/silicon dioxide composite." Microporous and Mesoporous Materials 197 (October 2014): 299–307. http://dx.doi.org/10.1016/j.micromeso.2014.06.026.

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13

Gunathilake, Chamila, and Mietek Jaroniec. "Mesoporous calcium oxide–silica and magnesium oxide–silica composites for CO2 capture at ambient and elevated temperatures." Journal of Materials Chemistry A 4, no. 28 (2016): 10914–24. http://dx.doi.org/10.1039/c6ta03916b.

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Incorporation of basic metal species (oxides) such as magnesium oxide and calcium oxide into porous materials is a logical strategy for enlarging the uptake of acidic greenhouse gases such as CO₂.

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Ravichandran, K., S. Vaishnavi, and D. Nedumaran. "Synthesis and Characterization of Nanocrystalline MgO for Optical Applications Using Sol-Gel Method." Advanced Materials Research 646 (January 2013): 76–83. http://dx.doi.org/10.4028/www.scientific.net/amr.646.76.

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This paper describes the preparation and characterization of nanocrystalline Magnesium Oxide (MgO) using sol-gel technique for optical applications. The prepared nanocrystalline MgO was chemically homogeneous, very pure and specifically hydroxylated and was characterized by standard techniques. The size of the prepared nanoparticle was found to be 27.38 nm ± 0.65 nm and exhibited a face centered–cubic structure and exhibited two lifetimes viz., 1 = 0.24 ns and 2 = 8.9 ns. Its binding energy was found to be 50.9 eV, which showed the formation of single phase MgO on the surface. It behaved as semiconductor over the temperature range of 500 °C to 660 °C and as perfect insulator in the temperature range 100 °K to 300 °K.

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Resende, João, Carmen Jiménez, Ngoc Duy Nguyen, and Jean-Luc Deschanvres. "Magnesium-doped cuprous oxide (Mg:Cu2 O) thin films as a transparent p-type semiconductor." physica status solidi (a) 213, no. 9 (July 28, 2016): 2296–302. http://dx.doi.org/10.1002/pssa.201532870.

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Glasson, D. R. "Reactivity of lime and related oxides. IX. Hydration of magnesium oxide." Journal of Applied Chemistry 13, no. 3 (May 4, 2007): 119–23. http://dx.doi.org/10.1002/jctb.5010130304.

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Fornaro, Teresa, John Robert Brucato, Sergio Branciamore, and Amaranta Pucci. "Adsorption of nucleic acid bases on magnesium oxide (MgO)." International Journal of Astrobiology 12, no. 1 (October 22, 2012): 78–86. http://dx.doi.org/10.1017/s1473550412000444.

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AbstractThe adsorption of organic molecules on mineral matrices might have played a fundamental role in processes that led to the emergence of life. We investigated the adsorption properties of the nucleobases adenine, cytosine, uracil and hypoxanthine on magnesium oxide (MgO), determining the single solute batch equilibrium adsorption isotherms. Langmuir-type isotherms were fitted to data, assuming a rapid reversible equilibration of adsorption, demonstrated effectively through desorption experiments. The Langmuir equilibrium adsorption constantKand the amount of the solute per unit of adsorbent mass necessary to complete the monolayerbwere calculated. The results indicate that MgO is a good adsorbent for nucleobases (adenine > uracil > hypoxantine > cytosine), suggesting a role of metal oxides in concentrating biomolecules in prebiotic conditions that might have favoured the passage from geochemistry to biochemistry.

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Choi, Hyungsoo, and Soontaik Hwang. "Sol-gel-derived Magnesium Oxide Precursor for Thin-film Fabrication." Journal of Materials Research 15, no. 4 (April 2000): 842–45. http://dx.doi.org/10.1557/jmr.2000.0120.

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Magnesium oxide (MgO) precursors were prepared by the sol-gel method using magnesium acetate. The reaction products and intermediates obtained during the sol-gel processing of magnesium acetate under various conditions were analyzed thermally and spectroscopically. No organic groups were detected by infrared spectroscopy after heat treating the reaction products at 400 °C. A large exothermic differential thermal analysis peak below 400 °C demonstrated the oxidation of organic moieties in each product. It was found that the presence of an acid catalyst was crucial during the sol-gel processing of magnesium acetate to produce sols suitable for depositing MgO films. The MgO films fabricated on Si(111) substrates using the precursor sol showed (200) orientation regardless of the presence of surface oxides on the substrates.

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Timohin, A. V., R. S. Titov, and M. V. Kozlova. "Magnesite and bauxite ores as petrophysical objects of spectral-grade estimation based on electrometry (from the archives of oxide-metric exploration in the Ural deposits)." LITHOSPHERE (Russia) 21, no. 3 (July 8, 2021): 431–43. http://dx.doi.org/10.24930/1681-9004-2021-21-3-431-443.

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Research subject. Distribution of magnesite and bauxite ores in mining blocks of deposits according to electrical conductivity in connection with signals of scattered phases of Ca, Mg and Al oxides. Petrophysical objects and differentiation of the properties of oxides detected in the boundary area and at the boundary with dielectrics, the semiconductor range in the geochemical environment of metamorphic formations from carbonate sediments.Materials and methods. An approach of searching for stationary features was applied. First, a study at the elemental level (review) was undertaken. Further, the authors’ electrometric measurements of the deposits were analyzed. Results. In the review part, the analysis of the metal constants – the relative electronegativity of the OEO (Luo and Benson scale), the electronic potentials E0, and the relationship of electrical resistance and pressure in pure elements was performed. The inversion of the properties of CaO ↔ MgO was revealed (for the first time in 2002–2004); Ca was identified as a reducing agent (CaO is a solid dielectric), which contradicts the current ideas about the comparative additivity of light Mg. It was established that MgO is a separate source of semiconductor carriers. Favourable conditions for studying the conductivity during the experimental part of the work were the absolute exchange increments of ore oxides at geological contacts. The properties of ores, rocks and oxides were measured and calculated. The relationships of the varietal growth of conductivity with compaction, increased basicity and magnetic susceptibility (magnetization) were predicted. This, in turn, provides a basis for studying cores, samples from debris, shredding and recycled geo-material, including concentrates, tailings and waste.Conclusions. The spectral properties of scattered oxides with atomic numbers ≤ 20 were identified. The activation effect of MgO and Al2O3 in the ionic medium (CaCO3 = CaO+CO2) was noted. In the phenomena of the semiconductor nature (n- and psources), a version of the donor-acceptor mechanism was proposed. The established properties are a factor in the implementation of measuring identification of oxides and ore grades in the conditions of deposits, both in the estimates of carbonate chemical types of terrigenous fossils, and plagioclase-pyroxene – in igneous ones. Varietal exploration and prototype electrometry were discussed from the standpoint of high-precision interpretation in the potential and replenishment combination of various petrophysical meters.

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Szczerba, Jacek, Ryszard Prorok, Paweł Stoch, Edyta Śnieżek, and Ilona Jastrzębska. "Position of Fe ions in MgO crystalline structure." Nukleonika 60, no. 1 (March 1, 2015): 143–45. http://dx.doi.org/10.1515/nuka-2015-0024.

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Abstract Magnesium oxide (MgO) is one of the most important raw materials in many branches of industry. Magnesium oxide is a popular refractory raw material because of its high refractoriness and high resistance to basic slags and environment. In many cases, use of MgO is limited by its properties, especially the presence of secondary phases like iron oxides. The amount and distribution of iron oxides can strongly influence the technological properties of MgO and depend on the manufacturing method, particularly the heat-treatment process. The aim of the study was to evaluate the influence of the heat-treatment process on amount and distribution of iron ions in a magnesium oxide lattice. The 57Fe Mössbauer effect measurements of fused and sintered magnesium oxide samples doped by the iron oxide were conducted. Investigation reveals in both cases the presence of Fe2+ as well as Fe3+ ions. Fe2+ ions occupy Mg2+ octahedral sites in the MgO lattice, whereas the Fe3+ ions are located in highly distorted octahedral coordination. The amount of Fe2+ varies from around 66% for fused samples to 30% for sintered samples.

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Lu, Dongzhu, Yanliang Huang, Jizhou Duan, and Baorong Hou. "A Zinc-Rich Coating Fabricated on a Magnesium Alloy by Oxide Reduction." Coatings 9, no. 4 (April 25, 2019): 278. http://dx.doi.org/10.3390/coatings9040278.

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The corrosion resistance of magnesium alloys could be enhanced by covering metallic coatings on the surface. The zinc-rich coating is one of these metallic coatings. To fabricate a zinc-rich coating on magnesium alloys, the substrate should be pretreated carefully, and a protective atmosphere is usually required. In this research, a zinc-rich coating was successfully fabricated on the AZ91D magnesium alloy in air by a diffusion alloying method, with zinc oxide as the zinc source. At the same time, the pretreatment of the magnesium alloy matrix was greatly simplified. The as-diffusion-alloyed zinc-rich intermetallic layer was investigated, utilizing SEM, EDS, and XRD, respectively. It is inferred that zinc oxide was reduced into Zn atoms by the active Mg atoms, and the Mg atoms were coming from the magnesium alloy matrix. Then the Zn atoms passed through the oxide film and formed an intermetallic layer on the magnesium alloy surface. Thus, taking advantage of the activity of Mg atoms, magnesium alloys could be surface alloyed with oxides.

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Farrah, S. R., and D. R. Preston. "Adsorption of Viruses by Diatomaceous Earth Coated with Metallic Oxides and Metallic Peroxides." Water Science and Technology 24, no. 2 (July 1, 1991): 235–40. http://dx.doi.org/10.2166/wst.1991.0065.

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Diatomaceous earth coated with oxides of aluminium, calcium, iron, magnesium, or manganese were not found to be useful for recovering viruses from water. The oxide coatings were not stable in water or only adsorbed viruses in small volumes of water. Further modification of coatings of magnesium oxide to make magnesium peroxide produced a modified diatomaceous earth that efficiently adsorbed viruses in water. Filters containing 3.5 g of diatomaceous earth adsorbed an average of greater than 90% of MS2, polio 1, coxsackie B5, and echo 5 in tapwater at approximately pH 8.5, even after 100 liters of tapwater had passed through the filters. From 15 to 40% of MS2 or enteroviruses could be recovered from tapwater using filters containing diatomaceous earth coated with magnesium peroxide.

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Hu, Jonathan, and Xue Yuan Nie. "Effect of Nanostructured Oxide Coatings on Tensile Properties of Cast Pure Magnesium." Advanced Materials Research 1088 (February 2015): 18–22. http://dx.doi.org/10.4028/www.scientific.net/amr.1088.18.

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In this work, nanostructured magnesium oxides were formed by PEO process on cast pure magnesium and the tensile properties of thin (5.8 μm) and thick (11.2 μm) coated samples were evaluated. The results obtained by uniaxial tensile testing show that the thin PEO coating had very little effect on the ultimate tensile strength (UTS) and elongation of the cast pure magnesium, while its yield strength was somewhat decreased. For the thick coated sample, both the yield strength and UTS decreased considerably, but the variation of the elongation was moderate, compared to the uncoated sample. The microstructures characterized by SEM revealed that the high porosity content and the large size of pores in the thick PEO coating should be responsible for the significant reduction in the properties of cast pure magnesium. The relationship between the tensile properties and microstructure of the PEO coated samples suggests that the thin PEO coating should be selected to protect the pure magnesium for biodegradable applications.

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Willey, R. J., S. A. Oliver, G. Oliveri, and G. Busca. "Chemistry and structure of mixed magnesium ferric oxide aerogels." Journal of Materials Research 8, no. 6 (June 1993): 1418–27. http://dx.doi.org/10.1557/jmr.1993.1418.

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Fine particles of mixed oxides having the composition MgxFe2−2xO3−2x (x between 0 and 1.0) were prepared via the sol-gel supercritical drying route (aerogels). Samples were then postprocessed by heating in air at 773 K and 1073 K. The structure and chemistry of the samples were deduced through x-ray diffraction, thermal gravimetric and differential thermal analysis, infrared, and specular UV-visible measurements. Surface areas were measured by the BET method. The volume saturation magnetization and particle volume distribution of MgFe2O4 samples were deduced from vibrating sample magnetometer measurements. The samples with x = 0 and x = 0.5 were well-crystallized α–Fe2O3 (hematite) and MgFe2O4 (magnesioferrite), respectively. Samples with 0 < x < 0.5 consisted of disordered lacunar spinels containing an excess of Fe3+ with respect to the spinel stoichiometry and a small amount of Fe2+. Samples heated above 773 K showed progressive segregation of α–Fe2O3. The sample with x = 0.66 was a mixture of a spinel phase and a hydrotalcite-like mixed Fe–Mg hydroxy compound containing methoxy and acetate ions. By heating in air, a monophasic Mg-excess spinel-type structure was obtained. The samples with 0.66 < x < 0.86 were mixtures of a spinel-type phase and another mixed Mg–Fe compound. When heated in air, the samples gave a mixture of MgO (probably containing Fe ions) and MgFe2O4. The saturation magnetization of MgFe2O4 samples is comparable to those previously reported, with the as-produced sample having a mean particle radius of 5.5 nm.

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Zamani, Asghar, Ahmad Poursattar Marjani, and Mojtaba Abedi Mehmandar. "Synthesis of high surface area magnesia by using walnut shell as a template." Green Processing and Synthesis 8, no. 1 (January 28, 2019): 199–206. http://dx.doi.org/10.1515/gps-2018-0066.

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Abstract In the present study, high surface area amorphous magnesia was synthesized using walnut shell as a template. This green, simple and useful synthetic protocol was based on the precipitation of magnesium nitrate on biomass in an aqueous phase, followed by calcination. Materials were characterized using X-ray diffraction, scanning electron microscopy (SEM) and N2 adsorption/desorption porosimetry, and the results exhibited high surface area for magnesium oxide. Furthermore, the pore size and surface area of these mesoporous materials can be adjusted by varying the biomass/magnesium nitrate ratio. In addition, magnesium oxide was studied as the support of palladium nanoparticles for the aerobic oxidation of alcohols. We have found out that the resulting Pd-loaded material acts as an effective catalytic system for the aerobic oxidation of benzylic and aliphatic alcohols. The catalyst can be recovered and reused three times without loss of activity. Also, to test the catalytic activity of magnesium oxides as a solid catalyst, we selected Meerwein-Ponndorf-Verley reduction of cyclohexanone with 2-propanol over different magnesium oxides.

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Pan, Mingqiang, Jun Sheng, Jizhu Liu, Zeming Shi, and Lei Jiu. "Design and Verification of Humidity Sensors Based on Magnesium Oxide Micro-Arc Oxidation Film Layers." Sensors 20, no. 6 (March 20, 2020): 1736. http://dx.doi.org/10.3390/s20061736.

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Humidity detection range is an important indicator for measuring the performance of humidity sensors, but semiconductor humidity sensors often face the problems of narrow detection ranges and insufficient detection sensitivities. In this paper, a magnesium oxide (MgO) humidity sensor based on micro-arc oxidation (MAO) technology was designed to solve these problems by simultaneously using impedance and capacitance as the response signals, as well as by normalizing the output of the two signals. The experimental results showed that the average output of the micro-arc MgO ceramic film, with impedance as the response signal, could reach 150 in the low relative humidity(RH) range (11.3–67% RH), which was much higher than its sensitivity in the high humidity range (< 1), and the film showed fast response (13 s) and recovery (61 s). Under high humidity conditions (67–97.3% RH), with capacitance as the response signal, the output of the micro-arc MgO was as high as 120. Therefore, the micro-arc MgO humidity sensor with impedance, and the sensor with capacitance as the response signal, demonstrated good stability in low humidity and in high humidity environments, respectively, indicating that the method of selecting appropriate response signals for different humidity environments can be applied to extend the humidity detection range of sensing material, and to improve the humidity detection capability of a sensor.

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da Forno, Anna, Massimiliano Bestetti, Nora Lecis, Stefano Paolo Trasatti, and Monica Trueba. "Anodic Oxidation and Silane Treatment for Corrosion Protection of AM60B Magnesium Alloy." Materials Science Forum 690 (June 2011): 413–16. http://dx.doi.org/10.4028/www.scientific.net/msf.690.413.

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Oxide films have been produced on AM60B magnesium alloy using micro-arc oxidation process in an environmentally friendly alkaline solution with and without addition of different oxides nanoparticles (TiO2, ZrO2 and Al2O3). In order to seal the oxides porosity generated in the sparking process, a silane-based top coat has been applied. The surface morphology of samples was analyzed by Scanning Electron Microscopy (SEM). Scratch tests were performed for evaluating the adhesion strength of the anodic oxides. The corrosion resistance of the oxide- silane- based topcoat composite coatings was evaluated in 3.5% NaCl solution using anodic polarization tests. The anodizing in oxides nanoparticles rich solutions (ZrO2 or Al2O3), followed by a silane top coat treatment performed using OSi as precursor, is an interesting way to synthesize adherent corrosion resistant coatings on magnesium alloy AM60B.

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Delahoy, Alan E., Shou Peng, Payal Patra, Surya Manda, Akash Saraf, Yunfei Chen, Xuehai Tan, and Ken K. Chin. "Cadmium Tin Oxide and Zinc Magnesium Oxide Prepared by Hollow Cathode Sputtering for CdTe Photovoltaics." MRS Advances 2, no. 53 (2017): 3203–14. http://dx.doi.org/10.1557/adv.2017.407.

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ABSTRACTThis work reports the fabrication and characterization of superstrate-type Zn1-xMgxO/CdTe heterojunction solar cells on both CdxSnyO and commercial SnO2:F transparent conducting oxides (TCOs) in which the ZMO and CTO layers are produced for the first time by hollow cathode sputtering. The sputtering is conducted in a reactive mode using metal or alloyed metal targets fitted to a custom-made linear cathode. It is notable that the CdS buffer layer conventionally employed in CdTe solar cells is entirely replaced by the ZMO window layer. The use of ZMO is found to eliminate the blue loss associated with CdS optical absorption and further results in a higher open-circuit voltage. Key parameters were found to be the conduction band offset at the ZMO/CdTe interface and the ZMO thickness. It was discovered that the ZMO exhibits intense photoluminescence even at room temperature. Most of the solar cells were fabricated in the FTO/ZMO/CdTe configuration although CTO/ZMO/CdTe solar cells were also demonstrated. The CTO was produced with an electron mobility of 46 cm2 V-1s-1 without any post-deposition annealing or treatment.

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Klabunde, Kenneth J., and Hiromi Matsuhashi. "A comparison of electron donor and proton abstraction activities of thermally activated pure magnesium oxide and doped magnesium oxides." Journal of the American Chemical Society 109, no. 4 (February 1987): 1111–14. http://dx.doi.org/10.1021/ja00238a020.

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Hsu, Yu-Ting, Che-Chi Lee, Wen-How Lan, Kai-Feng Huang, Kuo-Jen Chang, Jia-Ching Lin, Shao-Yi Lee, Wen-Jen Lin, Mu-Chun Wang, and Chien-Jung Huang. "Thickness Study of Er-Doped Magnesium Zinc Oxide Diode by Spray Pyrolysis." Crystals 8, no. 12 (December 6, 2018): 454. http://dx.doi.org/10.3390/cryst8120454.

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Erbium-doped magnesium zinc oxides were prepared through spray pyrolysis deposition at 450 °C with an aqueous solution containing magnesium nitrate, zinc acetate, erbium acetate, and indium nitrate precursors. Diodes with different erbium-doped magnesium zinc oxide thicknesses were fabricated. The effect of erbium-doped magnesium zinc oxide was investigated. The crystalline structure and surface morphology were analyzed using X-ray diffraction and scanning electron microscopy. The films exhibited a zinc oxide structure, with (002), (101), and (102) planes and tiny rods in a mixed hexagonal flakes surface morphology. With the photoluminescence analyses, defect states were identified. The diodes were fabricated via a metallization process in which the top contact was Au and the bottom contact was In. The current–voltage characteristics of these diodes were characterized. The structure resistance increased with the increase in erbium-doped magnesium zinc oxide thickness. With a reverse bias in excess of 8 V, the light spectrum, with two distinct green light emissions at wavelengths of 532 nm and 553 nm, was observed. The light intensity that resulted when using a different operation current of the diodes was investigated. The diode with an erbium-doped magnesium zinc oxide thickness of 230 nm shows high light intensity with an operational current of 80 mA. The emission spectrum with different injection currents for the diodes was characterized and the mechanism is discussed.

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Vasil’eva, N. A., L. M. Plyasova, and G. V. Odegova. "Defective magnesium oxides with oxygen-containing anion fragments incorporated in the oxide structure." Kinetics and Catalysis 50, no. 6 (November 2009): 816–18. http://dx.doi.org/10.1134/s0023158409060032.

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Garg, Shaffy, Sanjeev Gautam, Jitendra Pal Singh, Asokan Kandasami, and Navdeep Goyal. "Characterizing the defects and ferromagnetism in metal oxides: The case of magnesium oxide." Materials Characterization 179 (September 2021): 111366. http://dx.doi.org/10.1016/j.matchar.2021.111366.

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Hameed, Hussein Abdullah. "Enhanced Ultraviolet Photodetector Based on Mg-Doped ZnO Nanorods Films." Al-Mustansiriyah Journal of Science 29, no. 3 (March 10, 2019): 158. http://dx.doi.org/10.23851/mjs.v29i3.636.

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Magnesium-doped zinc oxide (ZnO: Mg) nanorods and nanotubes films were prepared by hydrothermal method deposited on glass substrates. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), photoluminescence (PL), and optical absorption spectroscopy (UV) were performed to characterize the prepared films. X-ray diffraction analysis showed a decrease in the lattice parameters of Mg doped ZnO NRs. The Photoluminescence of the undoped and Mg-doped ZnO NRs displayed a near band edge. At 10 V bias, the metal-semiconductor-metal (MSM) ultraviolet (UV) photodetector performance of the Mg-doped ZnO prepared for various Mg concentrations of 0.0, 0.02, and 0.06 was investigated under radiation of 40μW/cm2 at the wavelengths of 365 and 385 nm UV light. The responsivity, detectivity and quantum efficiency of Mg-doped based on MSM detector were 0.118A/W, 1.0579*1012 and 40.05157 under UV of wavelength 365nm respectively.

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34

Gehringer, Sabrina, Christoph Luckeneder, and Helmut Flachberger. "Investigations on the Triboelectrostatic Charging Behaviour and the Triboelectrostatic Sortability of Different Oxides." BHM Berg- und Hüttenmännische Monatshefte 165, no. 10 (October 2020): 525–31. http://dx.doi.org/10.1007/s00501-020-01025-7.

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AbstractIn the course of this study, several test series were carried out to investigate the triboelectrostatic charging behaviour of various oxides. At the beginning, the influence of the degree of aging and the influence of the sample storage on the charging efficiency of the oxide samples was analysed. For this purpose, two oxide samples were stored under different environmental conditions and then sorted using triboelectrostatic belt separation. Results of a previous series of tests showed that an increased feed temperature has a negative effect on the charging behaviour of calcium and magnesium oxide. Therefore, the effects of a reduced feed temperature were also examined. For these experiments, samples were stored at 8 °C under exclusion of air. In addition, a series of tests was carried out with a gradual increase of the voltage on the triboelectrostatic belt separator in order to determine possible differences in the charging efficiency of calcium oxide and magnesium oxide and to subsequently use them for the separation.

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35

Straumal, Petr B., Natalia Martynenko, Daria Amelina, Aleksey Nekrasov, and Sergey Dobatkin. "Phase Composition and Properties of Magnesium-Ceramic Composites after High Pressure Torsion." Defect and Diffusion Forum 385 (July 2018): 218–22. http://dx.doi.org/10.4028/www.scientific.net/ddf.385.218.

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The structure and properties of a composite consisting of Mg–Y–Nd–Zr alloy (WE43) and various oxides are studied. The particles of the WE43 powder were coated by the nanocrystalline oxide layer by means of a wet chemical deposition process. After that the powder is compressed into solid samples and deformed using high pressure torsion at room temperature. A second phase is present both in pure WE43 alloy and in the one with deposited oxides. We observed that the modification of the alloy by the oxide layer deposition and deformation by high pressure torsion changes the phase composition and properties of the samples.

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Zhao, Wei Min, Zhong Fang Shi, Zhi Feng Wang, Yong Yan Li, Jian Ding, Bo Young Hur, and Rui Zhao. "Effect of Rare-Earth Elements on the Ignition-Proof Behavior of Industrial Pure Magnesium." Materials Science Forum 654-656 (June 2010): 1464–67. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.1464.

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The purpose of this research is to investigate effect of rare-earth elements (Y and Dy) on industrial pure Mg through the ignition point test and oxide film analysis. The results show that the 0.5%Y can make the ignition point of pure magnesium about 30°C higher. However, the ignition point of pure magnesium can be multiplied about 50°C by the mixed additions of 0.5wt%Y and 5wt%Dy. The SEM analysis indicates the oxide film of Mg-0.5Y-5Dy is more compact and tenacious than that of Mg-0.5Y. The XRD analysis indicates that the oxide film of Mg-0.5Y-5Dy consists of MgO, Y2O3 and Dy2O3. The most of all the three oxides are Dy2O3, which can prevent magnesium from further oxidizing.

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Pilarska, Agnieszka, Marek Lukosek, Katarzyna Siwińska-Stefańska, Krzysztof Pilarski, and Teofil Jesionowski. "Use of MgO to Promote the Oxyethylation Reaction of Lauryl Alcohol." Polish Journal of Chemical Technology 16, no. 2 (June 26, 2014): 36–42. http://dx.doi.org/10.2478/pjct-2014-0027.

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Abstract Synthesis of magnesium hydroxide was performed by the precipitation method with the use of magnesium sulfate and sodium hydroxide. The infiuence of temperature and ratio of reagents was studied. Magnesium hydroxides, and the magnesium oxides obtained from them by thermal decomposition, were analyzed to determine their bulk density, polydispersity and particle size. The magnesium oxide with the largest surface area was tested as a catalyst in the oxyethylation of lauryl alcohol, and shown to be selective but poorly reactive in comparison with commercially available catalysts. Further studies are needed to improve its reactivity.

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Andreadelli, Aggeliki, Spyros Petrakis, Antiopi Tsoureki, George Tsiolas, Sofia Michailidou, Penelope Baltzopoulou, Robert van Merkestein, et al. "Effects of Magnesium Oxide and Magnesium Hydroxide Microparticle Foliar Treatment on Tomato PR Gene Expression and Leaf Microbiome." Microorganisms 9, no. 6 (June 4, 2021): 1217. http://dx.doi.org/10.3390/microorganisms9061217.

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Recently, metal oxides and magnesium hydroxide nanoparticles (NPs) with high surface-to-volume ratios were shown to possess antibacterial properties with applications in biomedicine and agriculture. To assess recent observations from field trials on tomatoes showing resistance to pathogen attacks, porous micron-scale particles composed of nano-grains of MgO were hydrated and sprayed on the leaves of healthy tomato (Solanum lycopersicum) plants in a 20-day program. The results showed that the spray induced (a) a modest and selective stress gene response that was consistent with the absence of phytotoxicity and the production of salicylic acid as a signalling response to pathogens; (b) a shift of the phylloplane microbiota from near 100% dominance by Gram (−) bacteria, leaving extremophiles and cyanobacteria to cover the void; and (c) a response of the fungal leaf phylloplane that showed that the leaf epiphytome was unchanged but the fungal load was reduced by about 70%. The direct microbiome changes together with the low level priming of the plant’s immune system may explain the previously observed resistance to pathogen assaults in field tomato plants sprayed with the same hydrated porous micron-scale particles.

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39

Toh, S. K., D. G. McCulloch, J. Du Plessis, P. J. K. Paterson, A. E. Hughes, D. Jamieson, B. Rout, J. M. Long, and A. Stonham. "An Investigation of the Native Oxide of Aluminum Alloy 7475-T7651 Using XPS, AES, TEM, EELS, GDOES and RBS." Surface Review and Letters 10, no. 02n03 (April 2003): 365–71. http://dx.doi.org/10.1142/s0218625x0300530x.

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The native oxide on the rolled aerospace aluminum alloy 7475-T7651 was characterized using a variety of different techniques, including X-ray Photoelectron Spectrometry (XPS), Auger Electron Spectrometry (AES), Transmission Electron Microscopy (TEM), Electron Energy Loss Spectrometry (EELS), Glow Discharge Optical Emission Spectrometry (GDOES), and Rutherford Backscattered Spectrometry (RBS). All techniques revealed that the native oxide layer is magnesium-rich and is probably a mixture of magnesium and aluminum–magnesium oxides.1 The oxide layer was found to be of nonuniform thickness due to the rolling process involved during the manufacture of this sheet alloy; this complicates analysis using techniques which have poor spatial resolution. Direct thickness measurement from cross-sectional TEM reveals an oxide thickness which varies between 125 and 500 nm. This large variation in thickness was also evident from GDOES and AES depth profiles as well as the RBS data. Both XPS and RBS also show evidence for the presence of heavy metals in the oxide.

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40

Vasil’eva, N. A., L. M. Plyasova, and G. V. Odegova. "Defect magnesium oxides containing acetate and nitrate ion fragments incorporated in the oxide structure." Kinetics and Catalysis 47, no. 3 (May 2006): 437–44. http://dx.doi.org/10.1134/s0023158406030165.

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41

Zhang, S., and Shu Sheng Jia. "Melting Temperatures of Several Oxides under Pressure." Materials Science Forum 546-549 (May 2007): 1817–20. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.1817.

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The melting temperature-pressure phase diagram [Tm(P)-P] for corundum (Al2O3), wustite (FeO) and magnesium oxide (MgO) are predicted through the Clapeyron equation where the pressure-dependent volume difference is modeled by introducing the effect of surface stress induced pressure. The model prediction is found to be consistent with the present experimental results.

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42

Amuthasurabi.M. "Fabrication of thin film transistor using magnesium zinc oxide (MgZnO) as a semiconductor layer by magnetron sputtering technique." Journal of Ceramic Processing Research 20, no. 1 (February 2019): 95–98. http://dx.doi.org/10.36410/jcpr.2019.20.1.95.

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43

Kong, Hui, Wei Dai, Shuai Shao, Qiang Yue, Jiang Xing Zhu, Hu Cheng Yao, and Bin Zheng Gan. "Microstructure Refinement in Low Carbon High Manganese Steel through Ti-Mg Deoxidation." Advanced Materials Research 482-484 (February 2012): 1640–44. http://dx.doi.org/10.4028/www.scientific.net/amr.482-484.1640.

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The low carbon high manganese steel (C: 0.07, Mn: 2.0, mass percentage) was deoxidized by Ti and Mg alloys, and its features of inclusion and microstructure were systemically studied. Through the scanning electron microscope (SEM) and Energy Dispersive X-ray Detector (EDX), it can be seen that in inclusions, the element of magnesium always coexists with titanium, and no single-phase oxides of magnesium are observed. After etching in 3Vol% natal solution, it’s found that the Mg-contained and Ti-contained inclusions can act as nucleation sits for the intragranular acicular ferrite. These results imply that besides the pinning effect, the oxide of magnesium can also participate in the nucleation for intragranular acicular ferrite. Thus, it may be used in the oxide metallurgy to refine the ferrite microstructure.

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44

Liu, Zhengqing, Zongyou Yin, Casandra Cox, Michel Bosman, Xiaofeng Qian, Na Li, Hongyang Zhao, Yaping Du, Ju Li, and Daniel G. Nocera. "Room temperature stable COx-free H2 production from methanol with magnesium oxide nanophotocatalysts." Science Advances 2, no. 9 (September 2016): e1501425. http://dx.doi.org/10.1126/sciadv.1501425.

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Methanol, which contains 12.6 weight percent hydrogen, is a good hydrogen storage medium because it is a liquid at room temperature. However, by releasing the hydrogen, undesirable CO and/or CO2 byproducts are formed during catalytic fuel reforming. We show that alkaline earth metal oxides, in our case MgO nanocrystals, exhibit stable photocatalytic activity for CO/CO2-free H2 production from liquid methanol at room temperature. The performance of MgO nanocrystals toward methanol dehydrogenation increases with time and approaches ~320 μmol g−1 hour−1 after a 2-day photocatalytic reaction. The COx-free H2 production is attributed to methanol photodecomposition to formaldehyde, photocatalyzed by surface electronic states of unique monodispersed, porous MgO nanocrystals, which were synthesized with a novel facile colloidal chemical strategy. An oxygen plasma treatment allows for the removal of organic surfactants, producing MgO nanocrystals that are well dispersible in methanol.

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45

Patah, Aep, Akito Takasaki, and Janusz S. Szmyd. "Synergetic Effect of Oxides on Hydrogen Reaction Kinetics of Magnesium Hydride." Materials Science Forum 561-565 (October 2007): 1605–8. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.1605.

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The kinetics of hydrogen reaction (absorption and desorption) on the MgH2 have been reported to be improved significantly by addition of transition metal oxides as catalysts. Among the oxides reported previously, Cr2O3 seems to improve hydrogen absorption kinetics and Nb2O5 for desorption kinetics. The catalytic effect of addition of more than one oxide, however, has not been reported yet. We investigated the hydrogen reaction kinetics of ball milled MgH2 powders added with either Cr2O3 or ZnO together with Nb2O5. In absorption reaction, the hydrogen contents reached 6 wt% and 5.3 wt% in 5 min for the powders added with 1 mol% ZnO + 1 mol% Nb2O5 and with 1 mol% Cr2O3 + 1 mol% Nb2O5, respectively. Those powders desorbed hydrogen up to about 4.5 wt% in 20 min. The significant improvement was not expected if one of the oxides was added separately. The combination of two kinds of oxides might play an important role for improvement of reaction kinetics.

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46

Tamai, Tsukasa, Koji Inazu, and Ken-ichi Aika. "Decomposition of Dichlorodifluoromethane with Simultaneous Halogen Fixation by Transition Metal Oxides Supported on Magnesium Oxide." Chemistry Letters 32, no. 5 (May 2003): 436–37. http://dx.doi.org/10.1246/cl.2003.436.

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Jabłońska, Eng Magdalena, Lorenzo Buselli, Eng Marek Nocuń, and Regina Palkovits. "Silver-Doped Cobalt (Magnesium) Aluminum Mixed Metal Oxides as Potential Catalysts for Nitrous Oxide Decomposition." ChemCatChem 10, no. 1 (November 10, 2017): 296–304. http://dx.doi.org/10.1002/cctc.201700777.

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48

Mohamed, Ruziana, Zuraida Khusaimi, A. N. Afaah, Aadila Aziz, Mohamad Hafiz Mamat, and Mohamad Rusop. "Effect of Annealing Temperature of Magnesium Doped Zinc Oxide Nanorods Growth on Silicon Substrate." Journal of Nano Research 26 (December 2013): 33–38. http://dx.doi.org/10.4028/www.scientific.net/jnanor.26.33.

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Magnesium (Mg)-doped zinc oxides (ZnO) have been prepared on a silicon substrate by using the solution-immersion method. The nanorods films were annealed at different temperature 0°C, 250°C, 500°C respectively for 1 hour. The XRD diffraction indicated that the Mg-doped ZnO nanorods have good crystallinity with a hexagonal wurzite structure preferentially oriented along the (002) direction. PL spectroscopy at room temperature shows strong UV peaks appearing at 383 nm when annealed at 250°C. The intensity of broad emission peaks increases with increasing annealing temperature to 500°C which is possibility attributed to intrinsic defects.

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49

Mikhailov, Gennady G., and L. A. Makrovets. "Thermodynamic Modeling of the Processes of Interaction of Calcium, Magnesium, Aluminum and Boron with Oxygen in Metallic Melts." Materials Science Forum 946 (February 2019): 162–68. http://dx.doi.org/10.4028/www.scientific.net/msf.946.162.

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A method for calculation of the diagrams of steel deoxidation and modification by calcium, magnesium, aluminum and boron was developed. The coordinates of the liquidus surfaces of the oxide systems B2O3–Al2O3–MgO, B2O3–Al2O3–CaO, B2O3–MgO–CaO were found at 1873 K. The energy parameters were determined for the theory of subregular ionic solutions of the studied oxide systems. The coordinates of the solubility surfaces for the systems Fe–Mg–Al–B–O, Fe–Ca–Al–B–O, Fe–Mg–Ca–Al–B–O were calculated. The effect of the total pressure on solubility of magnesium and calcium in liquid iron was studied. The activity of the components of the metallic melt was calculated using the first-order interaction parameters (Wagner's theory). The activities of the components of solid solutions (oxides and spinels) were equated with their molar fractions. It was shown that during extensive refining of metal from the oxygen, only a small fraction of boron oxidizes and these oxides form fraction of the oxide melts. The major non-metallic oxide inclusions were magnesia spinel, calcium bialuminate and liquid oxide formations. The "free" boron was dissolved in liquid metal in amounts which were in equilibrium with oxide phases.

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Zhang, Wei, Jim Metson, C. L. Nguyen, and S. Chen. "Surface Characterization of an Extruded 6060 Al Alloy." Advanced Materials Research 29-30 (November 2007): 67–70. http://dx.doi.org/10.4028/www.scientific.net/amr.29-30.67.

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The surface characteristics of an extruded 6060 aluminium alloy were investigated with X-ray Photoelectron Spectroscopy (XPS). The results revealed that the extruded surface was covered by oxides of aluminium and magnesium. The thickness of aluminium oxide was found to change along the extrusion direction with the thinnest and thickest oxide at the beginning and end of the extrudate, respectively. Magnesium segregation was found on the surface of the extrusion with the highest and lowest Mg concentration at the beginning and end of the extrudate, respectively. This is the inverse result of that expected where increasing Mg content was believed to be associated with film instability and thicker films.

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Journal articles on the topic 'Magnesium oxide Magnesium oxide Oxides. Semiconductors'

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