Articles de revues sur le sujet « Dioxide de niobium »

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1

Sheppard, L. R., A. J. Atanacio, T. Bak, J. Nowotny, M. K. Nowotny et K. E. Prince. « Niobium diffusion in niobium-doped titanium dioxide ». Journal of Solid State Electrochemistry 13, no 7 (6 novembre 2008) : 1115–21. http://dx.doi.org/10.1007/s10008-008-0717-x.

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Atanacio, Armand J., Tadeusz Bak et Janusz Nowotny. « Niobium Segregation in Niobium-Doped Titanium Dioxide (Rutile) ». Journal of Physical Chemistry C 118, no 21 (19 mai 2014) : 11174–85. http://dx.doi.org/10.1021/jp4110536.

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3

Sheppard, L. R. « Niobium Surface Segregation in Polycrystalline Niobium-Doped Titanium Dioxide ». Journal of Physical Chemistry C 117, no 7 (7 février 2013) : 3407–13. http://dx.doi.org/10.1021/jp311392d.

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4

Song, Li, Alexander Eychmueller, R. J. St. Pierre et M. A. El-Sayed. « Reaction of carbon dioxide with gaseous niobium and niobium oxide clusters ». Journal of Physical Chemistry 93, no 6 (mars 1989) : 2485–90. http://dx.doi.org/10.1021/j100343a050.

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Nico, C., M. R. N. Soares, M. Matos, R. Monteiro, M. P. F. Graça, T. Monteiro, F. M. Costa et M. A. Valente. « Exotic Manganese Dioxide Structures in Niobium Oxides Capacitors ». Microscopy and Microanalysis 18, S5 (août 2012) : 99–100. http://dx.doi.org/10.1017/s1431927612013153.

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The production of a Tantalum solid electrolytic capacitor requires the impregnation of MnO2 by pyrolysis in one of the several manufacturing steps. It has been reported that niobium oxides are a good alternative, presenting potentially better dielectric properties and a better cost effectiveness. Thus, it is important to study the conditions and the effect of the MnO2 impregnation on niobium oxide in order to understand and optimize the parameters of this process. The morphology and microstructure of the anode is one of the most important aspects that interfere with the dielectric properties of the capacitor. In this work, it is presented a study of the morphology and microstructure of different niobium oxide anodes after electrochemical oxidation (NbO/Nb2O5 core-shell grain structure), and after MnO2 impregnation with different pyrolysis temperatures. This impregnation is made by dipping the anodes, with the NbO/Nb2O5 core-shell structure, in a slurry of Mn(NO3)2. Heating this slurry while the anode is dipped, will lead to a pyrolysis reaction where the liberation of NO2 occurs as a gas, and where the product MnO2 solidifies around the grains.
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Sievers, M. R., et P. B. Armentrout. « Gas phase activation of carbon dioxide by niobium and niobium monoxide cations ». International Journal of Mass Spectrometry 179-180 (novembre 1998) : 103–15. http://dx.doi.org/10.1016/s1387-3806(98)14064-2.

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Cho, Yong Hoon, Soon Ki Jeong et Yang Soo Kim. « Electrochemical Properties of Chemically Etched-NbO2 as a Negative Electrode Material for Lithium Ion Batteries ». Advanced Materials Research 1120-1121 (juillet 2015) : 115–18. http://dx.doi.org/10.4028/www.scientific.net/amr.1120-1121.115.

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The electrochemical properties niobium dioxide (NbO2) was investigated as a negative electrode material for lithium ion batteries. The NbO2electrode showed a large irreversible capacity and small discharge capacity. The results of X-ray photoelectron spectroscopy indicate that the poor electrode performance of NbO2may be caused by niobium pentoxide (Nb2O5) formed on the surface of active material. The Nb2O5could be removed by chemical etching to some extent, thus improving the electrode performance.
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8

Muhammad Hussian, Hasan Mahmood, Muhammad Abdullah, Sikandar Raza,. « Computing Topological Indices for Niobium Dioxide and Metal-Organic Frameworks via M-Polynomials ». Power System Technology 48, no 1 (8 avril 2024) : 211–27. http://dx.doi.org/10.52783/pst.268.

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This paper investigates the topological properties of metal-organic frameworks and niobium dioxide using M-polynomials. The stability and wide range of bonding that the molecule exhibits make it a promising candidate for a number of uses, such as energy storage, gas detection, and catalysis. We use M-polynomials to calculate several degree-based topological indices for metal-organic frameworks and niobium dioxide. The M-polynomial is one such fundamental polynomial that provides a way to derive a multitude of degree-based topological indices. These indices are crucial for research in chemistry, biology, and physics and are derived from degree-based M-polynomials. This work develops a new M-polynomial algorithm for the computation and comparison of several degree-based molecular descriptors.
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Gautam, Subodh K., Arkaprava Das, S. Ojha, D. K. Shukla, D. M. Phase et Fouran Singh. « Electronic structure modification and Fermi level shifting in niobium-doped anatase titanium dioxide thin films : a comparative study of NEXAFS, work function and stiffening of phonons ». Physical Chemistry Chemical Physics 18, no 5 (2016) : 3618–27. http://dx.doi.org/10.1039/c5cp07287e.

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10

Alharthi, F. A., F. Cheng, E. Verrelli, N. T. Kemp, A. F. Lee, M. A. Isaacs, M. O’Neill et S. M. Kelly. « Solution-processable, niobium-doped titanium oxide nanorods for application in low-voltage, large-area electronic devices ». Journal of Materials Chemistry C 6, no 5 (2018) : 1038–47. http://dx.doi.org/10.1039/c7tc04197g.

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Synthesis and characterization of surface-stabilised, niobium-doped titanium dioxide (Ni-TiO2) nanorods in a simple one-step reaction using oleic acid as both a stabilizer and solubilizing agent.
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11

Kuanchaitrakul, Tanita, S. Chirachanchai et H. Manuspiya. « Niobium and Antimony-Modified Titanium Dioxide/Epoxy Thin Film for Proton Exchange Membrane Fuel Cell ». Advanced Materials Research 55-57 (août 2008) : 621–24. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.621.

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Inorganic Mesoporous Membrane is a new alternative to improve high-temperature fuel cell performance in proton exchange membrane fuel cells (PEMFCs) to substitute for Nafion. It possess high porosity and high specific surface areas, resulting in high proton conductivity. In this study, niobium-modified titania and antimony/niobium-modified titania ceramic were prepared via the sol-gel technique. The various contents of antimony, 0 to 3 wt%, and 3% niobium are incorporated into titania to improve the porous surface condition of the ceramic particles. The xerogels were heated at about 500°C. Inorganic membranes were prepared by using the spin-coating technique using epoxy resin as a binder. The physical, chemical, and electrical properties of these membranes were investigated. The XRD and Raman results showed that pure TiO2 and doped TiO2 nanoparticles obtained possess an anatase structure with mesoporosity. The specific surface area of the doped TiO2 was higher than that of pure TiO2 and it is worth pointing out that the doping of antimony affected the surface areas more than the doping of niobium in TiO2. Moreover, these membranes were also tested to evaluate their potential use as an electrolyte in PEMFC by using impedance spectroscopy, TGA, mechanical properties and water uptake.
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12

Bobkov, B. N., L. F. Goryachkina, E. A. Lavrent'ev, D. Yu Lyubimov et A. S. Panov. « Oxygen transport in the system niobium-uranium dioxide ». Soviet Atomic Energy 71, no 1 (juillet 1991) : 586–88. http://dx.doi.org/10.1007/bf01138004.

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13

Fu, Xin, Ruisong Li et Yucang Zhang. « High electrocatalytic activity of Pt on porous Nb-doped TiO2 nanoparticles prepared by aerosol-assisted self-assembly ». RSC Advances 12, no 34 (2022) : 22070–81. http://dx.doi.org/10.1039/d2ra03821h.

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A niobium-doped titanium dioxide electrocatalyst support for proton-exchange membrane fuel cells was prepared by an aerosol-assisted method and then loaded with platinum nanoparticles in the presence of ethylene glycol as a reducing agent.
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14

Sheppard, L. R., T. Dittrich et M. K. Nowotny. « The Impact of Niobium Surface Segregation on Charge Separation in Niobium-Doped Titanium Dioxide ». Journal of Physical Chemistry C 116, no 39 (20 septembre 2012) : 20923–29. http://dx.doi.org/10.1021/jp3065147.

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15

Li, Y., B. An, X. Xu, S. Fukuyama, K. Yokogawa et M. Yoshimura. « Surface structure of niobium-dioxide overlayer on niobium(100) identified by scanning tunneling microscopy ». Journal of Applied Physics 89, no 9 (mai 2001) : 4772–76. http://dx.doi.org/10.1063/1.1364649.

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16

Archana, P. S., Arunava Gupta, Mashitah M. Yusoff et Rajan Jose. « Tungsten doped titanium dioxide nanowires for high efficiency dye-sensitized solar cells ». Phys. Chem. Chem. Phys. 16, no 16 (2014) : 7448–54. http://dx.doi.org/10.1039/c4cp00034j.

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17

Sevic, John F., et Nobuhiko P. Kobayashi. « Multi-physics transient simulation of monolithic niobium dioxide-tantalum dioxide memristor-selector structures ». Applied Physics Letters 111, no 15 (9 octobre 2017) : 153107. http://dx.doi.org/10.1063/1.5003168.

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18

Sheppard, Leigh R., Armand J. Atanacio, Tadeusz Bak, Janusz Nowotny et Kathryn E. Prince. « Bulk Diffusion of Niobium in Single-Crystal Titanium Dioxide ». Journal of Physical Chemistry B 111, no 28 (juillet 2007) : 8126–30. http://dx.doi.org/10.1021/jp0678709.

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19

Haines, J., J. M. Léger, A. S. Pereira, D. Häusermann et M. Hanfland. « High-pressure structural phase transitions in semiconducting niobium dioxide ». Physical Review B 59, no 21 (1 juin 1999) : 13650–56. http://dx.doi.org/10.1103/physrevb.59.13650.

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Zhou, Mingfei, Zijian Zhou, Jia Zhuang, Zhen Hua Li, Kangnian Fan, Yanying Zhao et Xuming Zheng. « Carbon Dioxide Coordination and Activation by Niobium Oxide Molecules ». Journal of Physical Chemistry A 115, no 50 (22 décembre 2011) : 14361–69. http://dx.doi.org/10.1021/jp208291g.

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21

Marucco, Jean-Francis, Bertrand Poumellec, Jacques Gautron et Philippe Lemasson. « Thermodynamic properties of titanium dioxide, niobium dioxide and their solid solutions at high temperature ». Journal of Physics and Chemistry of Solids 46, no 6 (janvier 1985) : 709–17. http://dx.doi.org/10.1016/0022-3697(85)90160-x.

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22

Creeden, Jason A., Scott E. Madaras, Douglas B. Beringer, Irina Novikova et Rosa A. Lukaszew. « Growth and Characterization of Vanadium Dioxide/Niobium Doped Titanium Dioxide Heterostructures for Ultraviolet Detection ». Advanced Optical Materials 7, no 23 (18 septembre 2019) : 1901143. http://dx.doi.org/10.1002/adom.201901143.

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Ngo, Hai Dang, Kai Chen, Ørjan S. Handegård, Anh Tung Doan, Thien Duc Ngo, Thang Duy Dao, Naoki Ikeda, Akihiko Ohi, Toshihide Nabatame et Tadaaki Nagao. « Nanoantenna Structure with Mid-Infrared Plasmonic Niobium-Doped Titanium Oxide ». Micromachines 11, no 1 (24 décembre 2019) : 23. http://dx.doi.org/10.3390/mi11010023.

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Among conductive oxide materials, niobium doped titanium dioxide has recently emerged as a stimulating and promising contestant for numerous applications. With carrier concentration tunability, high thermal stability, mechanical and environmental robustness, this is a material-of-choice for infrared plasmonics, which can substitute indium tin oxide (ITO). In this report, to illustrate great advantages of this material, we describe successful fabrication and characterization of niobium doped titanium oxide nanoantenna arrays aiming at surface-enhanced infrared absorption spectroscopy. The niobium doped titanium oxide film was deposited with co-sputtering method. Then the nanopatterned arrays were prepared by electron beam lithography combined with plasma etching and oxygen plasma ashing processes. The relative transmittance of the nanostrip and nanodisk antenna arrays was evaluated with Fourier transform infrared spectroscopy. Polarization dependence of surface plasmon resonances on incident light was examined confirming good agreements with calculations. Simulated spectra also present red-shift as length, width or diameter of the nanostructures increase, as predicted by classical antenna theory.
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Bilalodin, Bilalodin, et Mukhtar Effendi. « KARAKTERISTIK FILM TIPIS TiO2 DOPING NIOBIUM ». Molekul 5, no 1 (1 mai 2010) : 10. http://dx.doi.org/10.20884/1.jm.2010.5.1.71.

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Niobium (Nb) doped Titanium dioxide (TiO2) thin films have been successfully grown using spin coating method. Characterizations of thin films was carried out using EDAX (Energy Dispersion Analysis for X-Ray), XRD (X-Ray Diffaction) and SEM (Scanning Electron Microscope) to determine the microstructure of thin films. Determination microstructure, particularly of crystal structure was examined using ICDD data, whereas porosity calculation was done using the toolbox application on Matlab 6.1 software. EDAX, XRD and SEM characterization show that the thin films grown well at the Si substrates with the (002) field orientation is dominant and the thin film has the rutile structure. The TiO2 : Nb thin films product have granules round, uniform grain size and porosity value of about 41%.
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Shibuya, Keisuke, et Akihito Sawa. « Epitaxial growth and polarized Raman scattering of niobium dioxide films ». AIP Advances 12, no 5 (1 mai 2022) : 055103. http://dx.doi.org/10.1063/5.0087610.

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We report the structural, electrical, and optical characterization of epitaxial niobium dioxide (NbO2) films fabricated on MgF2(001) substrates. The films were almost stoichiometric, had an indirect bandgap of 0.7 eV, and exhibited a phase transition at ∼1080 K. A polarized Raman scattering study of the films was conducted to investigate the Raman symmetry in the low-temperature phase. Based on the angular-dependent polarized Raman spectra, we assigned 13 modes to Ag symmetry and 14 to Bg symmetry. We also evaluated the Raman tensor elements of the Bg modes and found that the off-diagonal elements were nearly zero in most of the Bg modes, except for a phonon mode at 267 cm−1. This study aids understanding of the lattice dynamics of NbO2, which plays a critical role in the phase transition.
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Hadamek, Tobias, Agham B. Posadas, Ajit Dhamdhere, David J. Smith et Alexander A. Demkov. « Spectral identification scheme for epitaxially grown single-phase niobium dioxide ». Journal of Applied Physics 119, no 9 (7 mars 2016) : 095308. http://dx.doi.org/10.1063/1.4942834.

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Sheppard, L. R., T. Bak et J. Nowotny. « Electrical Properties of Niobium-Doped Titanium Dioxide. 1. Defect Disorder† ». Journal of Physical Chemistry B 110, no 45 (novembre 2006) : 22447–54. http://dx.doi.org/10.1021/jp0637025.

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Sheppard, L. R., T. Bak et J. Nowotny. « Electrical Properties of Niobium-Doped Titanium Dioxide. 2. Equilibration Kinetics† ». Journal of Physical Chemistry B 110, no 45 (novembre 2006) : 22455–61. http://dx.doi.org/10.1021/jp063703x.

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Li, Junjie, Shilie Pan, Xuelin Tian, Fangfang Zhang et Wenwu Zhao. « Dipotassium sodium niobium dioxide tetrafluoride, K2NaNbO2F4, crystal structure and characterization ». Journal of Physics and Chemistry of Solids 73, no 1 (janvier 2012) : 136–38. http://dx.doi.org/10.1016/j.jpcs.2011.10.024.

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Sheppard, L. R., T. Bak et J. Nowotny. « Electrical Properties of Niobium-Doped Titanium Dioxide. 3. Thermoelectric Power ». Journal of Physical Chemistry C 112, no 2 (janvier 2008) : 611–17. http://dx.doi.org/10.1021/jp0730491.

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Yousuf, M., et B. Lalevic. « Effect of switching on trapping centers in polycrystalline niobium dioxide ». Solid-State Electronics 32, no 6 (juin 1989) : 425–31. http://dx.doi.org/10.1016/0038-1101(89)90023-3.

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Atanacio, Armand J., et Yasuro Ikuma. « Surface Segregation of Niobium and Tantalum in Titanium Dioxide. Overview ». Journal of the American Ceramic Society 99, no 5 (15 février 2016) : 1512–19. http://dx.doi.org/10.1111/jace.14122.

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Atanacio, Armand J., Mohammad A. Alim, Tadeusz Bak, Mihail Ionescu et Janusz Nowotny. « Segregation in Titanium Dioxide Co-Doped with Indium and Niobium ». Journal of the American Ceramic Society 100, no 1 (6 octobre 2016) : 419–28. http://dx.doi.org/10.1111/jace.14490.

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Beebe, Melissa R., J. Michael Klopf, Yuhan Wang, Salinporn Kittiwatanakul, Jiwei Lu, Stuart A. Wolf et R. Alejandra Lukaszew. « Time-resolved light-induced insulator-metal transition in niobium dioxide and vanadium dioxide thin films ». Optical Materials Express 7, no 1 (20 décembre 2016) : 213. http://dx.doi.org/10.1364/ome.7.000213.

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Balakirev, V. F., T. V. Osinkina, S. A. Krasikov, E. M. Zhilina, L. B. Vedmid’ et S. V. Zhidovinova. « Joint metallothermic reduction of titanium and rare refractory metals of V group ». Izvestiya Vuzov Tsvetnaya Metallurgiya (Universities Proceedings Non-Ferrous Metallurgy) 1, no 1 (11 février 2021) : 57–65. http://dx.doi.org/10.17073/0021-3438-2021-1-57-65.

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The features of phase formation during the joint aluminothermic reduction of titanium, niobium, tantalum, vanadium from their oxides using methods of thermodynamic modeling, differential thermal and X-ray phase analysis were studied. Computer thermodynamic modeling made it possible to predict the optimal temperature conditions in the metallothermic process, composition and ratio of reagents in the charge, behavior of elements and sequence of phase formation. Thermodynamic calculations were supplemented by differential thermal studies using the combined scanning calorimetry method to identify the kinetic and thermochemical components of the process. An analysis of theoretical and experimental data allowed us to establish that the interaction of aluminum with titanium dioxide proceeds through the stage of titanium monoxide formation and features by the formation of TixAly intermetallic compounds of various compositions (TiAl3, TiAl, Ti2Al) depending on the Al and TiO2 ratio in the charge. When titanium dioxide is partially replaced by niobium, tantalum and vanadium oxides, the metallothermic process during interactions in the Al–TiO2–Nb2O5, Al–TiO2–Ta2O5 and Al–TiO2–V2O5 systems has a similar nature, enters the active phase once liquid aluminum appears, is accompanied by exothermic effects and features by the priority formation of titanium aluminides and binary and ternary intermetallic aluminum compounds with Group 5 rare refractory metals – AlNb3, Al3Nb, Al3Ta, Al3(Ti1–х, Taх), Al3(Ti0,8V0,2). The joint conversion of titanium dioxide and rare refractory metal pentoxides during the reduction process is carried out through sequential and parallel stages of the formation of simple and complex element oxides with low oxidation states.
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Volkovich, Vladimir A., Denis E. Aleksandrov, Trevor R. Griffiths, Boris D. Vasin, Timur K. Khabibullin et Dmitri S. Maltsev. « On the formation of uranium(V) species in alkali chloride melts ». Pure and Applied Chemistry 82, no 8 (4 juin 2010) : 1701–17. http://dx.doi.org/10.1351/pac-con-09-09-30.

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Uranyl(V) species are normally unstable in solutions but are here shown to be stable in high-temperature chloride melts. Reactions leading to the formation of UO2Cl43– ions were studied, including thermal decomposition and chemical reduction of uranyl(VI) chloro-species in various alkali chloride melts (LiCl, 3LiCl–2KCl, NaCl–KCl, and NaCl–2CsCl) at 550–850 °C. Decomposition of UO2Cl42– species under reduced pressure, with inert gas bubbling through the melt or using zirconium getter in the atmosphere results in the formation of UO2Cl43– and UO2. Elemental tellurium, palladium, silver, molybdenum, niobium, zirconium, and hydrogen, as well as niobium and zirconium ions were tested as the reducing agents. The outcome of the reaction depends on the reductant used and its electrochemical properties: uranyl(VI) species can be reduced to uranyl(V) and uranium(IV) ions, and to uranium dioxide.
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Sheppard, L., T. Bak, J. Nowotny, C. C. Sorrell, S. Kumar, A. R. Gerson, M. C. Barnes et C. Ball. « Effect of niobium on the structure of titanium dioxide thin films ». Thin Solid Films 510, no 1-2 (juillet 2006) : 119–24. http://dx.doi.org/10.1016/j.tsf.2005.12.272.

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Ahmad, A., J. Thiel et S. Ismat Shah. « Structural effects of niobium and silver doping on titanium dioxide nanoparticles ». Journal of Physics : Conference Series 61 (1 mars 2007) : 11–15. http://dx.doi.org/10.1088/1742-6596/61/1/003.

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Bolzan, Adrian A., Celesta Fong, Brendan J. Kennedy et Christopher J. Howard. « A Powder Neutron Diffraction Study of Semiconducting and Metallic Niobium Dioxide ». Journal of Solid State Chemistry 113, no 1 (novembre 1994) : 9–14. http://dx.doi.org/10.1006/jssc.1994.1334.

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Wen, Qin, Xuexin Yuan, Qiqi Zhou, Hai-Jian Yang, Qingqing Jiang, Juncheng Hu et Cun-Yue Guo. « Solvent- and Co-Catalyst-Free Cycloaddition of Carbon Dioxide and Epoxides Catalyzed by Recyclable Bifunctional Niobium Complexes ». Materials 16, no 9 (4 mai 2023) : 3531. http://dx.doi.org/10.3390/ma16093531.

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CO2, as a cheap and abundant renewable C1 resource, can be used to synthesize high value-added chemicals. In this paper, a series of bifunctional metallic niobium complexes were synthesized and their structures were characterized by IR, NMR and elemental analysis. All of these complexes have been proved to be efficient catalysts for the coupling reaction of CO2 and epoxides to obtain cyclic carbonates under solvent- and co-catalyst-free conditions. By using CO2 and propylene oxide as a model reaction, the optimal reaction conditions were systematically screened as: 100 °C, 1 MPa, 2 h, ratio of catalyst to alkylene oxide 1:100. Under the optimal reaction conditions, the bifunctional niobium catalysts can efficiently catalyze the coupling reaction with high yield and excellent selectivity (maximum yield of >99% at high pressure and 96.8% at atmospheric pressure). Moreover, this series of catalysts can also catalyze the coupling reaction at atmospheric pressure and most of them showed high conversion of epoxide. The catalysts have good substrate suitability and are also applicable to a variety of epoxides including diepoxides and good catalytic performances were achieved for producing the corresponding cyclic carbonates in most cases. Furthermore, the catalysts can be easily recovered by simple filtration and reused for at least five times without obvious loss of catalytic activity and selectivity. Kinetic studies were carried out preliminarily for the bifunctional niobium complexes with different halogen ions (3a(Cl−), 3b(Br−), 3c(I−)) and the formation activation energies (Ea) of cyclic carbonates were obtained. The order of apparent activation energy Ea is 3a (96.2 kJ/mol) > 3b (68.2 kJ/mol) > 3c (37.4 kJ/mol). Finally, a possible reaction mechanism is proposed.
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41

Wilhelm, Michael E., Michael H. Anthofer, Robert M. Reich, Valerio D'Elia, Jean-Marie Basset, Wolfgang A. Herrmann, Mirza Cokoja et Fritz E. Kühn. « Niobium(v) chloride and imidazolium bromides as efficient dual catalyst systems for the cycloaddition of carbon dioxide and propylene oxide ». Catal. Sci. Technol. 4, no 6 (2014) : 1638–43. http://dx.doi.org/10.1039/c3cy01057k.

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Imidazolium bromides combined with niobium(v) choride were used as catalyst system for the reaction of CO2 with epoxides to cyclic carbonates. The variation of the cation structure strongly affects the properties of the imidazolium salt and therefore the catalytic activity.
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42

Wang, Yuhan, Ryan B. Comes, Salinporn Kittiwatanakul, Stuart A. Wolf et Jiwei Lu. « Epitaxial niobium dioxide thin films by reactive-biased target ion beam deposition ». Journal of Vacuum Science & ; Technology A : Vacuum, Surfaces, and Films 33, no 2 (mars 2015) : 021516. http://dx.doi.org/10.1116/1.4906143.

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43

Balagurov, L. A., I. V. Kulemanov, A. F. Orlov et E. A. Petrova. « Electrical conductivity of titanium dioxide layers doped with vanadium, cobalt, and niobium ». Russian Microelectronics 41, no 8 (17 novembre 2012) : 503–7. http://dx.doi.org/10.1134/s1063739712080045.

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44

Li, Zhenwei, Xuan Luo, Wenjuan Wu et Jiagang Wu. « Niobium and divalent-modified titanium dioxide ceramics : Colossal permittivity and composition design ». Journal of the American Ceramic Society 100, no 7 (3 avril 2017) : 3004–12. http://dx.doi.org/10.1111/jace.14850.

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45

Takakusagi, Satoru, Takafumi Ogawa, Hiromitsu Uehara, Hiroko Ariga, Ken-ichi Shimizu et Kiyotaka Asakura. « Electrodeposition Study on a Single-crystal Titanium Dioxide Electrode : Platinum on a Niobium-doped Titanium Dioxide(110) Electrode ». Chemistry Letters 43, no 11 (5 novembre 2014) : 1797–99. http://dx.doi.org/10.1246/cl.140706.

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46

Basiaga, M., W. Walke, Z. Paszenda, A. Taratuta, B. Rynkus, J. Kolasa, T. Cichoń et E. Kompert‐Konieczna. « Properties of silicon dioxide coatings obtained by nano physical vapor deposition (PVD) method on the titanium 13‐niobium 13‐zirconium alloy ». Materialwissenschaft und Werkstofftechnik 55, no 5 (mai 2024) : 622–27. http://dx.doi.org/10.1002/mawe.202400014.

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AbstractSurface modification techniques play an important role in adjusting the physicochemical properties of titanium and its alloys. To reduce the penetration of alloying element ions into the body, various types of oxide coatings are used to protect it from the corrosive environment. Another important issue related to the surface layer requirement is ensuring an appropriate set of mechanical properties. Accordingly, in this study, the mechanical and electrochemical properties of the silicon dioxide layers formed by the deposition of nano physical vapor deposition on the surface of titanium and titanium 13‐niobium 13‐zirconium alloy samples were investigated. To evaluate the mechanical properties of the layers produced by this method, hardness tests were carried out, as well as tests on the adhesion of these layers to the metal substrate. On the other hand, electrochemical properties were studied using potentiodynamic measurements to assess the resistance to pitting corrosion, followed by impedance measurements to interpret the processes and phenomena occurring at the silicon dioxide layer/electrolyte interface. The data obtained showed different mechanical and electrochemical properties of the silicon dioxide layers generated with varying process parameters.
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47

Meng, Lei. « Improving the Characteristics of Niobium-Doped Titanium Dioxide Nanofilm with Moderate Hydrogen Incorporation ». ECS Journal of Solid State Science and Technology 10, no 2 (1 février 2021) : 025005. http://dx.doi.org/10.1149/2162-8777/abe2ec.

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48

Matsui, Tsuneo, et Keiji Naito. « Electrical conductivity measurement and thermogravimetric study of pure and niobium-doped uranium dioxide ». Journal of Nuclear Materials 136, no 1 (octobre 1985) : 59–68. http://dx.doi.org/10.1016/0022-3115(85)90030-3.

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Orita, Nozomi. « Generalized Gradient Approximation +UStudy for Metallization Mechanism of Niobium-Doped Anatase Titanium Dioxide ». Japanese Journal of Applied Physics 49, no 5 (20 mai 2010) : 055801. http://dx.doi.org/10.1143/jjap.49.055801.

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50

Alcalde, M. Isabel, M. Pilar Gómez-Sal et Pascual Royo. « Competitive Insertion of Isocyanide and Carbon Dioxide into Niobium− and Silicon−Amido Bonds ». Organometallics 20, no 22 (octobre 2001) : 4623–31. http://dx.doi.org/10.1021/om0103963.

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