catena-Poly[[[bis[(-)-O-bornyldithiocarbonato-κ2S,S']nickel(II)]-μ-4,4'-bipyridine-κ2N:N'] chloroform disolvate]

The Ni atom in the linear polymeric title complex, {[Ni(C₁₁H₁₇OS₂)₂(C₁₀H₈N₂)]·2CHC1₃}_n or {Ni[S₂C(-)-OC₁₀H₁₇)]₂(NC₅H₄C₅H₄N)·2CHC1₃}_n, is octahedrally coordinated within a trans-N₂S₄ donor set. There are two crystallographically independent polymers and two independent CHC1₃ molecules in the structure. For each polymer unit, the Ni atom and the axis of the 4,4'-bipyridine ligand are located on a twofold axis.

Micro-porous nickel produced by powder metallurgy

Micro-porous nickel (Ni) with an open cell structure was fabricated by a special powder metallurgical process, which includes the adding of a space-holding material. The average pore size of the micro-porous Ni samples approximated 30 μm and 150 μm, and the porosity ranged from 60 % to 80 %. The porous characteristics of the Ni samples were observed using scanning electron microscopy (SEM) and the mechanical properties were evaluated using compressive tests. For comparison, porous Ni samples with a macro-porous structure prepared by both powder metallurgy
(pore size 800 μm) and the traditional chemical vapour deposition (CVD) method (pore size 1300 μm) were also presented. Results indicated that the porous Ni samples with a micro-porous structure exhibited different deformation behaviour and dramatically increased mechanical properties,
compared to those of the macro-porous Ni samples.

Preparation and characterisation of open-cell microporous nickel

In the present study, nickel foams with an open cell microporous structure were fabricated by the so-called space-holding particle sintering method, which included the adding of a particulate polymeric material (PMMA). The average pore size of the nickel foams approximated 10.5 μm; and the porosity ranged from 70 % to 80 %. The porous characteristics of the nickel foams were observed using scanning electron microscopy and the mechanical properties were evaluated using compressive tests. For comparison, nickel foams with an open-cell macroporous structure (pore size approximately 1.3 mm) were also presented. Results indicated that the nickel foams with a microporous structure possess enhanced mechanical properties than those with a macroporous structure.

Characterisation of nickel(II) extraction by 2-hydroxy-5-nonylacetophenone oxime (LIX 84) in a micellar phase

The properties of the nickel(II)/2-hydroxy-5-nonylacetophenone oxime (HNAPO), an active ingredient in LIX 84, extraction system were characterised in a micellar system. The extinction coefficient, λ_max of HNAPO (316 nm) and the Ni²⁺ complex (387 nm) in a neutral micellar system, poly dispersed octa-ethyleneglycol mono-n-dodecyl ether (G₁₂A₈) were determined as 3100 and 3500 M⁻¹ cm⁻¹, respectively. HNAPO was found to have a neutral micellar phase and bulk aqueous phase pK_a of 11.5 and 12.5, respectively. The extraction equilibrium constant, K_ex, was determined to be 10^−8.0, and the deviation from theory observed at high pH can be accounted for by consideration of the competition for nickel(II) ions by hydroxide ions and HNAPO. A micellar phase of octa-ethyleneglycol mono-n-dodecyl ether (C₁₂E₈) was determined to be an appropriate model of the free oil/water interface from the solubilised location of HNAPO. Utilising the interfacial probe, 4-heptadecyl-7-hydroxy coumarin (HHC) allowed the determination of the electrostatic surface potential of mixed micelles of G₁₂A₈ and sodium dodecyl sulphate (SDS) or dodecyl trimethyl ammonium chloride (DTAC). The electrostatic surface potential was a linear function of the number of additional surfactant monomers within the G₁₂A₈ micelle, for the concentration range studied. For G₁₂A₈/DTAC mixed micelles, the surface potential was given by +1.1 mV per DTAC molecule per micelle, and for G₁₂A₈/SDS mixed micelles the relationship was −1.4 mV per SDS molecule per micelle.

Joining magnesia partially stabilised zirconia with nickel by current enhancement

This study confirms that current enhancement is a reliable and efficient method for joining ceramic and metal. Experiments indicated very high bond strengths. Mathematical modelling explained the mechanism of joining and has established critical functions for design and control.

Anisotropic mechanical properties of nickel foams fabricated by powder metallurgy

In the present study, porous nickel foam samples with pore sizes of 20 μm and 150 μm and porosities of 60 % and 70 % were fabricated by the space-holding sintering method via powder metallurgy. Electron scanning microscopy (SEM) and Image-Pro Plus were used to characterise the morphological features of the porous nickel foam samples. The anisotropic mechanical properties of porous nickel foams were investigated by compressive testing loading in different directions, i.e. the major pore axis and minor pore axis. Results indicated that the nominal stress of the nickel foam samples increases with the decreasing of the porosity. Moreover, the foam sample exhibited significantly higher nominal stress for loading in the direction of the major pore axis than loading in direction of the minor pore axis. It is also noticeable that the nominal stress of the nickel foams increases with the decreasing of the pore size. It seems that the deformation behaviour of the foams with a pore size in the micron-order differs from those with a macro-porous structure.

Crystal orientation characterisation of electrodeposited nanocrystalline nickel alloy

The collection contains EBSD maps of annealed nanocrystalline Ni and Ni-Fe alloys. The maps show the variation of crystallographic texture across mesoscale colonies within these alloys.

Microtexture characterisation of electrodeposited nanocrystalline nickel

This data includes transmission electron microscopy orientation maps of the received electrodeposited nanocrystalline nickel. The data was obtained using the Nanomegas Digitstar System which is currently the only equipment of this type available in Australia. The data has been acquired with steps in nanometre scale and enables the determination of local microtexture of the specimens.

Effect of gold on the corrosion behavior of an electroless nickel/immersion gold surface finish

The performance of surface finishes as a function of the pH of the utilized plating solution was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests in 3.5 wt.% NaCl solution. In addition, the surface finishes were examined by x-ray diffraction (XRD), and the contact angle of the liquid/solid interface was recorded. NiP films on copper substrates with gold coatings exhibited their highest coating performance at pH 5. This was attributed to the films having the highest protective efficiency and charge transfer resistance, lowest porosity value, and highest contact angle among those examined as a result of the strongly preferred Au(111) orientation and the improved surface wettability.

A novel non-enzymatic glucose sensor based on nickel (II) oxide electrospun nanofibers

A new enzymeless glucose sensor has been fabricated via electrospinning technology and subsequent calcination. The morphology and structure of the as-prepared nanofibers have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The electrocatalytic oxidation of glucose in alkaline medium at nickel oxide modified glassy carbon electrodes has been investigated. The modified electrodes offer excellent electrocatalytic activity toward the glucose oxidation at low positive potential (0.3 V). Glucose has been determined chronoamperometrically at the surface of NiO nanofibers modified electrode in 0.5 mM NaOH. Under the optimized condition, the calibration curve is linear in the concentration range of 2 × 10−3 mM∼1 mM, and 1 mM∼9.5 mM. The detection limit (signal-to-noise 3) and response time are 3.394 × 10−6 M and 2 s, respectively. The NiO electrospun nanofibers is easy to prepare and feasible in economy. The modified electrode is steady and can be used repeatedly, so it is reasonable to expect its broad use in non-enzymatic glucose sensor.

Dye-sensitised solar cell with nickel cathode

The present invention relates to a cathode for use in a dye-sensitised solar cell which comprises a redox couple, wherein the cathode comprises: (a) metallic nickel; and (b) intrinsically conducting polymer that, during operation of the cell, reduces an oxidised species of the redox couple.

Effect of heat treatment on diffusion, internal friction, microstructure and mechanical properties of ultra-fine-grained nickel severely deformed by equal-channel angular pressing

Severe plastic deformation via equal-channel angular pressing was shown to induce characteristic ultra-fast diffusion paths in Ni (Divinski et al., 2011). The effect of heat treatment on these paths, which were found to be represented by deformation-modified general high-angle grain boundaries (GBs), is investigated by accurate radiotracer self-diffusion measurements applying the 63Ni isotope. Redistribution of free volume and segregation of residual impurities caused by the heat treatment triggers relaxation of the diffusion paths. A correlation between the GB diffusion kinetics, internal friction, microstructure evolution and microhardness changes is established and analyzed in detail. A phenomenological model of diffusion enhancement in deformation-modified GBs is proposed.