In order to examine whether catalyst granular size was a factor for tar removal and syngas composition enhancement, three Ni/char catalysts with 90-100 mesh (Ni/SC), 50-60 mesh (Ni/MC), and 20-30 mesh (Ni/LC) size were prepared with a mechanical mixing method and tested in an updraft gasifier. Reforming parameters investigated were the reaction temperature (650-850C), the Ni loading (5-20% of ...

—The recent discovery of herbivores that feed on Ni-hyperaccumulating plants and contain elevated Ni concentrations in their bodies suggests that Ni may be transferred to their predators. We tested this hypothesis using the high-Ni herbivore Melanotrichus boydi and four predator species: the spiders Pholcus phalangioides and Misumena vatia, the mantid Stagmomantis californica and the lacewing C...

Inanga (Galaxias maculatus) are a euryhaline and amphidromous Southern hemisphere fish species inhabiting waters highly contaminated in trace elements such as nickel (Ni). Ni is known to exert its toxic effects on aquatic biota via three key mechanisms: inhibition of respiration, impaired ion regulation, and stimulation of oxidative stress. Inanga acclimated to freshwater (FW), 50% seawater (SW...

This study investigated the effect of reaction time (minutes to months) on the surface coordination environment of Ni sorbed onto pyrophyllite using XAFS. The data suggest the appearance of multinuclear Ni complexes after a reaction time of minutes. As reaction time !>rogresses, these multinuclear Ni complexes increased in size «NNi-Ni 1.4-4.5). Ni-Ni bond distances (2.99-3.03 A) were similar t...

Nymphs of Stenoscepa sp. feed on leaves of the Ni hyperaccumulator Berkheya coddii at serpentine sites in Mpumalanga Province, South Africa. These sites contain Ni hyperaccumulators, Ni accumulators, and plants with Ni concentrations in the normal range. We conducted studies to: (i) determine the whole-body metal concentration of nymphs (including those starved to empty their guts); (ii) compar...

Let {S′Ni | i ∈ IN} represent a set consequence operators defined on the language Λ, where each member of {S′Ni | i ∈ IN} corresponds to a science-community physical theory. It is shown that there exists a hyperfinite ultralogic U ∈ ∗Cf defined on all internal subsets of Λ such that U 6 = U, and, for each i ∈ IN, S Ni ( ∗Ni) = U( ∗Ni). For each internal Y ⊂ Λ, ⋃ { S Ni (Y ) | i ∈ IN} ⊂ U(Y ) ⊂ ...

(61)Ni chemical shifts of Ni(all-trans-cdt)L (cdt = cyclododecatriene, L = none, CO, PMe(3)), Ni(CO)(4), Ni(C(2)H(4))(2)(PMe(3)), Ni(cod)(2) (cod = cyclooctadiene) and Ni(PX(3))(4) (X = Me, F, Cl) are computed at the GIAO (gauge-including atomic orbitals), BPW91, B3LYP and BHandHLYP levels, using BP86-optimised geometries and an indirect referencing scheme. For this set of compounds, substituen...

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...

Meglumine diatrizoate ("Renografin-76", a radiographic contrast medium) contains sufficient nickel to cause hypernickelemia in patients after coronary arteriography. Nickel analyses by electrothermal atomic absorption spectrophotometry showed that nine lots of "Renografin-76" (760 g of meglumine diatrizoate per L) contained 144 +/- 44 micrograms Ni per L. Serum Ni concentrations became elevated...