نتایج جستجو برای: niobium

تعداد نتایج: 3152  

Journal: :Dalton transactions 2014
Steven Hananouchi Brandon T Krull Joseph W Ziller Filipp Furche Alan F Heyduk

Isostructural vanadium, niobium and tantalum complexes of bis(3,5-di-tert-butyl-2-phenol)amine ([ONO]H3), were prepared and characterized to evaluate the impact of the metal ion on redox-activity of the ligand platform. New vanadium and niobium complexes with the general formula, [ONO]MCl2L (M = V, L = THF, 1-V; M = Nb, L = Et2O, 1-Nb) were prepared and structurally analysed by X-ray crystallog...

2015
Torsten Wieduwilt Alessandro Tuniz Sven Linzen Sebastian Goerke Jan Dellith Uwe Hübner Markus A. Schmidt

Due to the ongoing improvement in nanostructuring technology, ultrathin metallic nanofilms have recently gained substantial attention in plasmonics, e.g. as building blocks of metasurfaces. Typically, noble metals such as silver or gold are the materials of choice, due to their excellent optical properties, however they also possess some intrinsic disadvantages. Here, we introduce niobium nanof...

Journal: :Dalton transactions 2013
Dimitriy Malyshev Francisco Boscá Charles-Oneil L Crites Geniece L Hallett-Tapley José Carlos Netto-Ferreira Emilio I Alarcon Juan C Scaiano

The size of photochemically-prepared niobium nanoparticles (NbNP) can be controlled by varying the concentration of the photoinitiator in the reaction mixture. The particles, which may be metallic in nature, are readily oxidized upon air exposure to form stable niobium(v) oxide nanoparticles (NbONP) that act as strong Brønsted acids.

2015
Tobias Junginger Rebecca Seviour Wolfgang Weingarten Carsten Welsch

At CERN a compact Quadrupole Resonator has been developed for the RF characterization of superconducting samples at different frequencies. In this contribution measurements on bulk niobium and niobium film on copper samples are presented. Surface resistance results are being correlated to surface analyses measurements carried out on the same samples.

Journal: :Dalton transactions 2015
A S Bozzi R L Lavall T E Souza M C Pereira P P de Souza H A De Abreu A De Oliveira P F R Ortega R Paniago L C A Oliveira

In this paper we show a very simple route for the incorporation of catalytically active niobium species on the surface of carbon materials, such as graphene oxide, carbon nanotubes and activated carbon. Some existing methods of incorporating a transition metal on a support have involved co-precipitation or wet impregnation, to obtain the corresponding oxides. These methods, however, cause reduc...

Azizi, Soltanieh,

In the present research, to form niobium carbide coating on the surface of AISI L2 steel Thermo-Reactive Deposition method (TRD) in a molten bath was used. Niobium carbide coating treatment was carried out at 1173 K, 1273 K, and 1373 K for 2, 4, and 8 hours. The molten bath contained 20wt.% borax (Na2B4O7), 5 wt.% boric acid (B2O3), and 75 wt.% ferro-niobium. The presence and properties of...

2001
H. M. J. R. H. Ross

The promoting effect of niobium in a Li/MgO catalyst for the oxidative coupling of methane (OCM) and for the oxidattve dehydrogenation of ethane (ODHE) has been studied in some detail. it has been found that a Li/Nb/MgO catalyst with 16 wt % niobium showed the highest activity for the C, production in the OCM reaction; the activity at 600 “C was ten times that of the Li/MgO catalyst at the same...

2008
Louis Hand Michael Skvarla

In order to test the microwave properties of superconductors, we are developing a disk resonator, to be operated in the TM010 mode at 3.36 GHz. The goal is a measurement of microwave surface resistance at both low and high power, initially for niobium thin films, but eventually for other thin film superconductors. The currents in a disk resonator flow in and out radially. Edge currents are zero...

1995
D. C. Larbalestier P. J. Lee

After a very active period of Niobium Titanium superconductor strand development in the mid 1980s, progress slowed as the SSC scaled up for production and emphasis moved towards guaranteeing, rather than enhancing performance. However, this period also produced several advances in the understanding of flux pinning in Niobium Titanium alloys and in the fabrication of composites containing artifi...

2001
P H Dederichs

We calculate the electronic structure of 3d impurities in niobium and molybdenum. Our calculations rely on the local density approximation of density functional theory. Assuming a muffin-tin description of the atomic potentials, the impurity potential and the ones of the nearest neighbours are calculated self-consistently while the embedding of this perturbed cluster into the host is described ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید