• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.7
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• pp.79-87
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• 1998

Nitrided oxides which have been investigated as alternative gate oxide for metal-oxide-semiconductor field effect devices were grown by two-step process using N$_{2}$O gas, and were chaacterized via a fowler-nordheim tunneling(FNT) electron injection technique. Electrical characteristics of nitrided gate oxides were superior to that of control oxides.Further, the FNT electron injection into the nitrided gate oxides reveals that gate oxides degrade more both if electrons were foreced to inject from the gate metal and if thicker nitrided gate oxides were used in the thickness range of 90~130.angs.. Models are suggested to explain these phenomena.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.277-289
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• 2003

This study proposes a mathematical model to characterize the removal of nitrogen oxides in a dielectric barrier discharge plasma process. As well as the reactions between nitrogen oxides, water vapor, oxygen and nitrogen, the model takes into account the effect of ethylene often used as a chemical additive to reduce the power consumption of the process on the removal of nitrogen oxides. Since the concentrations of the radicals concerned in the main reactions including O, OH, H and N should be calculated to predict the removal efficiency of nitrogen oxides, they were theoretically derived. The parameters affecting the removal of nitrogen oxides, such as initial concentration, discharge power, humidity, and ethylene concentration were experimentally evaluated, which were compared with the calculated results to verify the validity of the model proposed. The predicted concentrations of several byproducts formed in this process were also presented and discussed. The effects of several parameters mentioned above on the removal of nitrogen oxides were reasonable described by the proposed model.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.542-545
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• 1987

THE ELECTRICAL CHARACTERISTICS Of RAPID THERMAL OXIDES AND NITRIDED OXIDES HAVE BEEN INVESTIGATED. R.T.OXIDE FILMS HAVE BEEN PREPARED BY ONLY R.T. OXIDATION OR R.T.OXIDATION AND SUBSEQUENT R.T.ANNEAL. NITRIDED OXIDE FILMS HAVE BEEN PREPARED BY R.T.OXIDATION AND SUBSEQUENT R.T.NITRIDATION.AND CONVENTIONAL OXIDES ALSO HAVE BEEN PREPARED TO COMPARE WITH R.T.P OXIDES. R.T.ANNEALED OXIDES SHOW EXCELLENT BREAKDOWN FIELD. LEAKAGE CURRENT AND TDDB CHARACTERISTICS. ALSO, CAPACITANCE Of R.T NITRIDED OXIDES ARE SUPERIOR BY 10% TO CONVENTIONAL OXIDES, BUT TDDB CHARACTERISTIC ARE POORER THAN OXIDE FILMS.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.71-79
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• 1992

Selective extraction procedure has been used to quantify copper and cadmium In association with the various phases of aquatic sediment such as exchangeable/adsorbed, carbonate, manganese oxides, organic matter and iron oxides. Changes of pH influenced on the partitioning of copper in carbonate and exchangeable/ad- sorbed phases and of cadmium in carbonate phase of aquatic sediment. Addition of NTA and EDTA, copper and cadmium associated with carbonate phase were released from sediment to water. Total partitioning coefficient was 8.361 for copper and 0.497 for cadmium. The relative binding strengths of copper and cadmium to each solid phase can be ranked by using the partitioning coefficints. For copper it was observed that carbonate > organic matter > exchangeable/adsorbed > manganese oxides > iron oxides and for cadmiunm it was observed that exchangeable/adsorbed > carbonate > manganese oxides > organic matter > iron oxides.

• Journal of Institute of Convergence Technology
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• v.3 no.2
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• pp.7-10
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• 2013

Metal oxides are known as stable materials during a thermal treatment. However, some oxides are readily evaporated at high temperatures. A voloxidation process is a head-end process for a pyroprocessing dealing with spent nuclear fuels (SF). In SFs, fission productions are in the form of oxides and some of them would be evaporated during the voloxidation process. Therefore, it is of importance to analyse the vapor pressures of metal oxides so that the material flows throughout the pyroprocessing could be estimated. In this work, vapor pressures of relevant metal oxides were calculated and presented to draw a baseline on the material flow of the pyroprocessing.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.14-26
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• 2014

Copper is an important component from coin metal to electronic wire, integrated circuit, and to lithium battery. Copper oxides, mainly including $Cu_2O$ and CuO, are important semiconductors for the wide applications in solar cell, catalysis, lithium-ion battery, and sensor. Due to their low cost, low toxicity, and easy synthesis, copper oxides have received much research interest in recent year. Herein, we review the crystallization of copper oxides by designing various chemical reaction routes, for example, the synthesis of $Cu_2O$ by reduction route, the oxidation of copper to $Cu_2O$ or CuO, the chemical transformation of $Cu_2O$ to CuO, the chemical precipitation of CuO. In the designed reaction system, ligands, pH, inorganic ions, temperature were used to control both chemical reactions and the crystallization processes, which finally determined the phases, morphologies and sizes of copper oxides. Furthermore, copper oxides with different structures as electrode materials for lithium-ion batteries were also reviewed. This review presents a simple route to study the reaction-crystallization-performance relationship of Cu-based materials, which can be extended to other inorganic oxides.

• Journal of the Korean Ceramic Society
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• v.44 no.12
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• pp.660-682
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• 2007

An SOFC consists of all ceramic complex oxides each with different electrochemical-property requirements. These requirements, in principle, can be made met to a great extent by controlling or tailoring the defect structure of the oxide. This paper reviews the defect structure, nonstoichiometry as a measure of the total defect concentration, and the defect relaxation kinetics of complex oxides that are currently involved in a variety of growing applications today.

• Journal of Soil and Groundwater Environment
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• v.25 no.2
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• pp.9-15
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• 2020

This study was conducted to investigate the in situ formation of amorphous Fe oxides as a stabilization technology in As-contaminated soil. After addition of ferric nitrate and the neutralizing agent, most of extractable fractions of As in soil (i.e., SO₄^2- and PO₄^3--extractable As) was converted into As bound to amorphous Fe oxides. In addition, results of solubility bioavailability research consortium (SBRC) test indicated that a significant amount of As in untreated soil changed to a non-bioaccessible form after stabilization. The reason was attributed to the newly formed amorphous Fe oxides in the stabilized soil, which was confirmed by linear combination of fitting (LCF) using X-ray absorption spectroscopy (XAS) analysis. Interestingly, after five months of aging of the stabilized soil, ferrihydrite and schwertmannite newly formed in the soil were transformed to crystalline Fe oxides such as goethite, and further decrease in SBRC extractable fraction of As was observed. The results suggest that co-precipitated As with amorphous Fe oxides can be further immobilized with time, due to the crystallization of amorphous Fe oxides.

• Environmental Engineering Research
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• v.15 no.4
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• pp.183-190
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• 2010

Biogenic Mn oxides are expected to have great potential in the control of water pollution due to their high catalytic activity, although information on biological Mn oxidation is not currently sufficient. In this study, the growth of a Mn oxidizing microorganism, Pseudomonas putida MnB1, was examined, with the Mn oxides formed by this strain characterized. The growth of P. putida MnB1 was not significantly influenced by Mn(II), but showed a slightly decreased growth rate in the presence of Pb(II) and EE2, indicating their insignificant adsorption onto the cell surface. Mn oxides were formed by P. putida MnB1, but the liquid growth medium and resulting biogenic solids were poorly crystalline, nano-sized particles. Biogenic Mn oxidation by P. putida MnB1 followed Michaelis-Menten kinetics, with stoichiometric amounts of Mn oxides formed, which corresponded with the initial Mn(II) concentration. However, the formation of Mn oxides was inhibited at high initial Mn(II) concentration, suggesting mass transfer obstruction of Mn(II) due to the accumulation of Mn oxides on the extracellular layer. Mn oxidation by P. putida MnB1 was very sensitive to pH and temperature, showing sharp decreases in the Mn oxidation rates outside of the optimum ranges, i.e. pH 7.43-8.22 and around 20-$26^{\circ}C$.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.128-135
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• 1998

The paper gives a brief introduction to protonic defects and their chemistry, thermodynamics and transport in oxides. The temperature dependence of the equilibrium concentration of protons is illustrated and compared for different acceptor-doped oxides. The difficulties of saturating as well as emptying the oxides of protons are discussed. In order to illustrate the possibility of lattice relaxation of defects, a conceptual study is made of a case where the enthalpy of dissolution of protons(water) at the cost of oxygen vacancies is assumed dependent on the concentration of vacancies. It is shown how this changes the behavior of hydration curves vs temperature and water vapour pressure. finally, a discussion is given on the water uptake in heavily oxygen deficient oxides; how water uptake may affect order-disorder in the oxygen sublattice and eventually lead to defective, disordered or ordered oxyhydroxides or hydroxides of potential interest as intermediate temperature proton conductions.