In order to prepare Ni clusters embedded in amorphous Si3N4, Ni and Si3N4 layers have been alternatively deposited using sputtering techniques. The nominal Ni layer thickness ranged from 2 to 60 Å and the number of layers was varied accordingly so as to keep the total amount of Ni constant. Extended x-ray-absorption fine-structure EXAFS spectroscopy has been used to study the Ni clustering as w...

A Ni/meso-MgO catalyst with high surface area and small Ni nanoparticles was synthesized and investigated for hydrogen production by steam reforming of phenol for the first time. Compared to conventional Ni/MgO, the Ni/meso-MgO catalyst showed higher catalytic activity and stability. X-ray Diffraction, N2 adsorption, hydrogen temperature programmed reduction, transmission electron microscopy an...

We report a mechanistic study of the catalytic effect of Ni(OH)2 on hematite nanowires for photoelectrochemical water oxidation. Ni compounds have been shown to be good catalysts for electrochemical and photoelectrochemical water oxidation. While we also observed improved photocurrents for Ni-catalyst decorated hematite photoanodes, we found that the photocurrents decay rapidly, indicating the ...

A comparison was made of the bronchoalveolar lavage fluid (BALF) response to ultrafine nickel (Uf-Ni) and standard-sized nickel (Std-Ni). Rats were intratracheally instilled with 0, 0.1, 0.5, 1 and 5 mg Uf-Ni and Std-Ni, respectively. At 3 d after instillation, the body weight and wet lung weight were determined. At the same time, BALF was analyzed for lactate dehydrogenase (LDH), total protein...

The title compound, C(19)H(20)O(3), was obtained from 1,4-bis-(4-methyl-phen-yl)but-3-yn-2-one in the presence of carbon monoxide by Ni(CN)(2) catalysis in a basic aqueous medium. Inter-molecular O-H⋯O hydrogen bonds lead to the formation of hydrogen-bonded carb-oxy-lic acid dimers [graph-set motif R(2) (2)(8)]. Weak C-H⋯O hydrogen bonds between neighbouring dimers further extend the structure ...

The following integer programming.problem arises in the convergence analysis of rows of PadC approxir r mants for muomorphic functions: maximize };(ci>jC1j-(Jj~, subject to the constraints };C1j ='t, 0 S C1j S Cl>j, ~ j~ 1SiS r. Here the Cl>j and't are given positive integers, and the C1j are the integer unknowns. An algorithm is developed, by which all possible solutions can be conslrUcted, an...

Formation of secondary Ni precipitates is an important mechanism of Ni retention in neutral and alkaline clay/water systems. However, the structure and composition of these secondary phases, and their stability is still disputable. Using existing structure refinement data and new ab-initio FEFF 7 calculations we show that Ni-edge X-ray absorption fine structure spectroscopy alone may not be abl...

The sorption speciation of Ni(II) on Ca-montmorillonite was evaluated using a combination of batch experiments, extended X-ray absorption fine structure (EXAFS) spectroscopy and modeling. The pH and temperature at the aqueous-montmorillonite interface affects both the extent of Ni(II) sorption as well as the local atomic structure of the adsorbed Ni(II) ions. At 0.001 mol L(-1) Ca(NO(3))(2) and...

Reaction of the mononuclear Ni(II) thiolate complexes [Ni(L)] [L, L(1), H2L(1), bis(2-mercaptoethyl)-1,2-dimercaptoethane; L(2), H2L(2), N,N'-dimethyl-N,N'-bis(2-mercaptoethyl)-bis(aminoethyl)sulfide] with [FeCp(CO)2I] gives the dithiolate-bridged heterobimetallic species, [Ni(L(1))FeCp(CO)]PF6, 1, and [Ni(L(2))FeCp]I, 2, respectively. Binding of a Fe(CO)3 fragment via reaction of square-planar...

In the mol-ecular structure of the title compound, [NiCl2(C7H12N2S)2], the Ni(II) atom has a distorted tetra-hedral geometry, coordinated by two Cl atoms [Ni-Cl= 2.2336 (6) Å] and two thione S atoms [Ni-S= 2.3024 (6) Å]. The angles at the Ni(II) cation, which lies on a twofold rotation axis, are Cl-Ni-Cl = 115.58 (3)° and S-Ni-S = 94.55 (3)°. All other angles at the central Ni(II) atom range fr...