Results 181 to 190 of about 19,382 (232)

Synthesis of (Na2O,PbO)–Nb2O5, (Na2O,BaO)–Nb2O5, and (K2O,SrO)–Nb2O5 thin films using sol–gel method

Thin Solid Films, 2010
Abstract Homogeneous pore-free Ba 2 NaNb 5 O 15 , KSr 2 Nb 5 O 15 , and 2·Na 2 O–PbO–6·Nb 2 O 5 thin films were fabricated on sapphire substrates using the sol–gel technique. By controlling the gelation and coating process, thickness of thin films fabricated was controllable from ~ 40 nm to ~ 10 μm.
Fei Peng, Dongsheng Li
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Ruthenium–Niobia Interaction in Nb2O5-Supported and Nb2O5-Modified Ru Catalysts

Bulletin of the Chemical Society of Japan, 1994
Abstract The effect of H2 reduction treatments on H2 chemisorption, ethane hydrogenolysis, and CO hydrogenation over Nb2O5-supported and Nb2O5-modified Ru catalysts has been studied to elucidate the nature of the metal-oxide interaction, and the results are compared with those of a SiO2-supported Ru catalyst.
Kimio Kunimori, Hisakazu Shindo, Daisuke Nishio, Takeshi Sugiyama, Toshio Uchijima   +4 more
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Raman investigations of NH3 adsorption on TiO2, Nb2O5, and Nb2O5/TiO2

Catalysis Letters, 1994
A study has been carried out of the interactions of NH3 with TiO2, Nb2O5, and Nb2O5/TiO2. Raman spectroscopy was used to characterize the structure of the adsorbed NH3 and perturbations of species present at the surface of the adsorbent. On each oxide, NH3 adsorbs predominantly at Lewis acid sites.
Rusty M. Pittman, Alexis T. Bell
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Das System KNbO3-Nb2O5

Journal of Thermal Analysis, 1989
Das System KNbO3−Nb2O5 wurde mit thermoanalytischen, dilatometrischen und rontgenographischen Methoden neu untersucht. Acht ternare Verbindungen werden im Bereich von 0–50 Mol-% K2O gefunden. Nur K4Nb6O17 schmilzt kongruent, alle anderen zersetzen sich peritektisch.
R. Blachnik, E. Irle
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TiO2-Nb2O5 solid solutions

Journal of Materials Science Letters, 1987
Preparation et etude des parametres cristallins des solutions solides de TiO 2 et Nb 2 O 5 utilisables dans les glacures ...
J. S. Sanghera, J. Williamson
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Structural investigations of nitrided Nb2O5 and Nb2O5–SiO2 sol–gel derived films

Journal of Non-Crystalline Solids, 2008
Sol-gel derived ×Nb 2 O 5 -(100- ×)SiO 2 films (where x = 100, 80, 60, 50, 40, 20, 0 mol%) were nitrided at various temperatures (800°C, 900°C, 1000°C, 1100°C and 1200°C). The structural transformations occurring in the films as a result of ammonolysis were studied using X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron ...
B. Kościelska, A. Winiarski
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Interaction of pyridine on Nb2O5

Journal of Molecular Structure: THEOCHEM, 2005
Abstract We have studied the interaction of pyridine on oxide surface in order to characterize the Lewis acid sites. Ab initio RHF method was employed at 3-21G* all electron basis set level. The LanL2DZ effective core potential was also used and compared with all electron basis set results.
João B.L. Martins, Tiago A.S. Fialho
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The systems Y2O3-Nb2O5 and Ho2O3-Nb2O5: the cubic solid-solution region

Journal of Materials Science Letters, 1984
Determination des parametres cristallins en fonction de la composition dans la region cubique, par diffraction de ...
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Piezoelectric properties of Nb2O5 doped and MnO2?Nb2O5 co-doped Pb(Zr0.53Ti0.47)O3 ceramics

Journal of Materials Science: Materials in Electronics, 1995
The effects of Nb2O5 addition and MnO2‐Nb2O5 co-addition on the piezoelectric properties of Pb(Zr0.53Ti0.47)O3 (PZT) ceramics are investigated. When Nb2O5 is added to PZT, the planar coupling factor (Kp) significantly increases but the mechanical quality factor (QM) as well as the electrical quality factor (QE) decreases.
Jae-Hwan Park, Byung-Kook Kim, Kug-Hyun Song, SoonJa Park   +3 more
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I. The binary system Nb2O5 -SiO2 ; II. The binary system CaO-Nb2O5

1962
The binary system Nb205--S102 has been shown to include an extensive two-liquid region over the range 5 to 80% Nb205. The minimum temperature of the two-liquid area is 1695°C. A eutectic composition occurs at 95% Nb205 and 1448°C. and another at approximately 5% Nb2O5 and 1695°C. The experimental results were obtained by the cone-fusion method.
M Ibrahim, N F H Bright, J F Rowland
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