OBJECTIVE The aims of the study are to assess the marginal accuracy of base metal and titanium alloy casting and to evaluate the effect of repeated ceramic firing on the marginal accuracy of base metal and titanium alloy castings. MATERIALS AND METHODS Twenty metal copings were fabricated with each casting material. Specimens were divided into 4 groups of 10 each representing base metal alloy...

Bond paths and the bond critical point properties (the electron density (rho) and the Hessian of rho at the bond critical points (bcp's)) have been calculated for the bonded interactions comprising the nickel sulfide minerals millerite, NiS, vaesite, NiS(2), and heazlewoodite, Ni(3)S(2), and Ni metal. The experimental Ni-S bond lengths decrease linearly as the magnitudes of the properties each ...

Ni accumulation and utilization were studied in two strains of marine Synechococcus, isolated from both coastal (CC9311; clade I) and open-ocean (WH8102; clade III) environments, for which complete genome sequences are available. Both strains have genes encoding an Ni-containing urease and when grown on urea without Ni become Ni-N colimited. The Ni requirements of these strains also depend upon...

Cr-Ni coatings with the mass ratios of 17% Cr-83% Ni, 20% Cr-80% Ni and 24% Cr-76% Ni were fabricated on H13 hot work mould steel using a laser cladding (LC). The surface-interface morphologies, chemical elements, surface roughness and phase composition of the obtained Cr-Ni coatings were analysed using a scanning electron microscope (SEM), energy disperse spectroscopy (EDS), atomic force micro...

The transformation characterization of Ni(OH)2/NiOOH in Ni-Pt films was investigated using an electrochemical quartz crystal microbalance (EQCM) in an alkaline electrolyte under various experiment conditions. The Ni-Pt films were prepared by electro-deposition on gold-coated quartz crystal chips. When cyclic voltammetry (CV) was performed continually, the OH ions diffused into the Ni-Pt film to...

In this paper, the effect of Ni on the formation of Cu6Sn5 and Cu3Sn intermetallics between tin and (Cu,Ni)-substrates has been studied by making use of the thermodynamic assessment of the Sn-Cu-Ni system. The driving forces for the diffusion of the elements in the intermetallic layers were calculated as a function of Ni-content. Assuming constant mobilities of component atoms, the results sugg...

Mesoporous Ni–alumina catalysts (Ni–alumina-pre and Ni–alumina-post) were synthesized by one-step sol–gel method using micelle complex comprising lauric acid and nickel ion as a template with metal source and using aluminum sec-butoxide as an aluminum source. The Ni–alumina catalysts showed relatively high surface areas (303 m/g for Ni–alumina-pre and 331 m/g for Ni–alumina-post) and narrow por...

We present a natural extension of Andrews’ multiple sums counting partitions of the form (λ1, · · · , λm) with λi ≥ λi+k−1 + 2. The multiple sum that we construct is the generating function for the so-called K-restricted jagged partitions. A jagged partition is a sequence of non-negative integers (n1, n2, · · · , nm) with nm ≥ 1 subject to the weakly decreasing conditions ni ≥ ni+1− 1 and ni ≥ ...