Doping calcium phosphates with ionic species can play an important role in biological responses promoting alkaline phosphatase activity, and, therefore inducing the generation of new bone. Thus, in this study, the synthesis of niobium-doped hydroxyapatite (Nb-HA) nanosize particles obtained by the precipitation process in aqueous media followed by thermal treatment is presented. The bioceramics...

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 ...

Recently the UHV arc technology was proposed as a possible alternative for depositing thin superconducting films of pure niobium on the inside surface of RF cavities for particle accelerators. The paper describes status of research on deposition of superconducting films for RF accelerating cavities. New UHV arc based devices with planar and cylindrical niobium cathodes are presented. The main r...

We have fabricated and tested single photon detectors based on a current biased superconducting niobium nanowire patterned into a meander. The detectors are fabricated from high quality, ultra high vacuum sputtered niobium thin films on a sapphire substrate. For detection of single optical photons, we show that the superconductor’s intrinsic kinetic inductance does not limit the reset time of t...

The molecular structures of the surface overlayers of rhenium(VI1) oxide, molybdenum(V1) oxide, tungsten(V1) oxide, chromium(V1) oxide, vanadium(V) oxide, niobium(V) oxide, and titanium( IV) oxide on y-alumina were determined by in situ Raman spectroscopy under dehydrated conditions. It was found that the dehydrated surface metal oxide structures of all the systems under study, except for suppo...

This paper examines vanadium chloride solutions as electrolytes for an all-vanadium redox flow battery. The chloride solutions were capable of dissolving more than 2.3 M vanadium at varied valence states and remained stable at 0-50 °C. The improved stability appeared due to the formation of a vanadium dinuclear [V(2)O(3)·4H(2)O](4+) or a dinuclear-chloro complex [V(2)O(3)Cl·3H(2)O](3+) in the s...

Article history: Received on: 29/02/2016 Revised on: 15/03/2016 Accepted on: 06/04/2016 Available online: 28/05/2016 A simple HPLC method for determination of Benzalkonium chloride in various ophthalmic solutions was developed. The chromatographic analysis was achieved using CN column (250 mm, 4.6 mm i.d., 5 μm) with isocratic mobile phase consisting of acetonitrile phosphate buffer (pH 5.5; 0....

The DESY R&D program on cavities fabricated from large-grain niobium explores the potential of this material for the production of approximately 1000 nine-cell cavities for the European XFEL. The program investigates both basic material properties, comparing large grain material to standard sheet niobium, and material availability, production, and preparation aspects. Several single-cell caviti...