The controlled mobility of protons is a fundamental step in a series of chemical and biological reduction-oxidation processes, such as the reduction of dioxygen to water and the production/oxidation of hydrogen [1,2]. The tailoring of molecular electrocatalysts that effectively forms or cleaves the H-H bond is, therefore, extremely useful for the energy storage problem [3]. Such catalysts, resp...

Name: Jiong Hua Department: Physics Title: Commensurate Effect in Superconducting Niobium Films Containing Arrays of Nanoscale Holes Major: Physics Degree: Doctor of Philosophy

In this study, different samples of Niobium and Vanadium co-doped titania  thin films (5-10-15 mol% Nb and 5-10-15 mol% V) were prepared via sol−gel dip coating method, using niobium chloride as niobium precursor, ammonium metavanadate as vanadium precursor, and titanium (IV) butoxide (TBT) as titanium precursor. The effects of doping amount on the structural, optical, and photo-catalytic prope...

We investigated confinement effects on the resistive anisotropy of a superconducting niobium strip with a rectangular cross section. When its transverse dimensions are comparable to the superconducting coherence length, the angle dependent magnetoresistances at a fixed temperature can be scaled as R(theta,H) = R(H/Hctheta) where Hctheta =Hc0(cos2theta + gamma(-2)sin2theta)(-1/2) is the angular ...

Ab initio pseudopotential calculations have made for the structural, electronic, elastic, mechanical, and electron–phonon interaction properties of molybdenum borocarbide (Mo2BC) niobium boronitride (Nb2BN) superconductors. Analysis structural electronic reveals that nature bonding in both these compounds is a combination covalent, ionic, metallic. The near-Fermi states are occupied by d transi...

Photocatalytic splitting of water into H(2) and O(2) under visible light irradiation is achieved using a coumarin-dye-adsorbed lamellar niobium oxide for hydrogen evolution.

High gradient superconducting RF (SRF) cavities are needed for energy frontier superconducting accelerators. Progress has been made over the past decades and the accelerating gradient Eacc has been increased from a few MV/m to 42 MV/m in SRF niobium cavities. The corresponding peak RF magnetic field Hpk on the niobium cavity surface is approaching the intrinsic RF critical magnetic field Hcrit ...

We have found hexagonal symmetry in the dependence of Josephson current of triangle shape junctions upon external magnetic field. Niobium/aluminum-oxide/niobium junctions are fabricated using magnetron sputtering of niobium and thermal oxidation of aluminum layers. Selective niobium anodization process has been used to define junction areas. In the case of square shaped junction, dependence of ...

Niobium-92 (92Nb) decays to zirconium-92 (92Zr) with a half-life of 36 million years and can be used to place constraints on the site of p-process nucleosynthesis and the timing of early solar system processes. Recent results have suggested that the initial 92Nb/93Nb of the solar system was high (>10(-3)). We report Nb-Zr internal isochrons for the ordinary chondrite Estacado (H6) and a clast o...