Heavy metal uptake during anaerobic digestion of combined electroplating and brewery wastewaters

Batch and continuous culture laboratory-scale experiments were conducted to quantify the effect of combining chrome and nickel electroplating effluent (EE) and brewery effluent as substrate for established anaerobic digester granules. EE at a 1:12 ratio in brewery effluent was inhibitory to anaerobic digestion but acclimation at a 1:24 ratio occurred during continuous culture experiments. At least 90% of the chromium and nickel was absorbed by the granules with nickel attaching to granule perimeters while chromium penetrated into deeper recesses. © Rapid Science Ltd. 1998     

Highlighting the roles of transition metals and speciation in chemical biology

Transition metal ions play key structural and functional roles, affecting structures of biomolecules and enzyme function. The importance of transition metal ions in chemical biology is, thus, undisputed. However, the aqueous chemistry of metal ions is complicated because they form species in several protonation and redox states. In the presence of metabolites, metal ions can also form coordination complexes. The existence of several species is relevant because enzymes and membrane receptors can distinguish between species even when they are rapidly equilibrating. Thus, metal ions, enzyme cofactors, and therapeutic agents are sensitive to the metal ion speciation chemistry because it affects their interaction with enzymes and other biomolecules. Speciation is also crucial for metal-containing bioorthogonal reactions, since water and metabolites stabilize active catalysts, affect chemoselectivity and reaction yields.     

Detection of apoptotic bodies in nickel-treated root apical cells of <Emphasis Type="Italic">Allium cepa</Emphasis>

Nickel, a phytotoxic metal, is easily taken up by plant roots. Excessive Ni in soil can induce programmed cell death in root tips. DNA fragmentation was assessed by deoxyuracyl nick end labeling with fluorescein mediated by terminal deoxynucleotide transferase (TUNEL). In control roots, programmed cell death was observed by using TUNEL assay in the root cap and xylem vessels. At moderate Ni²⁺ concentrations (10–25 µM), cortical cells also showed TUNEL-positive reaction, indicating the Ni-induced cell death. The Ni-induced cell death differs from natural cell death in the appearance of spherical bodies of condensed chromatin and formation of apoptotic bodies. These apoptotic bodies resemble those appearing during animal apoptosis.From Fiziologiya Rastenii, Vol. 52, No. 1, 2005, pp. 151–153.Original English Text Copyright © 2005 by Samadi, Behboodi.This article was presented by the authors in English.     

Substrate-binding guides individual melibiose permeases MelB to structurally soften and to destabilize cytoplasmic middle-loop C3

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The role of chromium and nickel on the thermal and mechanical properties of FeNiCr austenitic stainless steels under high pressure and temperature: a molecular dynamics study

The effect of Cr and Ni content on thermo-mechanical properties of FeNiCr austenitic stainless steel under ambient and high pressure and temperature were investigated by MD simulations. The FCC structure was selected as optimum structure for FeNiCr system based on obtained MD results from Bonny EAM potential and valid experimental results. The structural and mechanical properties of pure Fe, Ni, and Cr were also estimated based on this potential, indicating good agreement with experimental results. These properties were computed for four experimental case studies which showed less than 10% error. Moreover, the elastic constants of the Fe–(8–18)Ni–(18–25)Cr systems were estimated. Results showed that bulk modulus increases by increasing the Ni and Cr contents, which can be connected to the changes in bonding electrons. The thermal properties of FeNiCr were calculated in ambient and high pressure. Although thermo-mechanical properties confirm good agreement with experimental results at the ambient condition, however, they indicate that FeNiCr Bonny potential is not applicable at high pressure. In order to tackle this issue, a hybrid potential was used at high Pressure/Temperature. The results illustrate enhanced mechanical properties, increase of melting point and reduction of LTE in high pressure and deteriorated mechanical properties at high temperature.     

Estimation of Incremental Unit Risks for Inhaled Nickel Subsulfide and Nickel Oxide,Based on a Combination of Human and Animal Data

Both animal and human exposure–response data are used to estimate the incremental unit risks (IURs) of lung cancer for Ni₃S₂ and NiO, which are constituent compounds of nickel refinery dust. The animal experiments are used to determine relative lung cancer potencies for Ni₃S₂ and NiO, and the human epidemiological data are used as the best estimate of overall risk for refinery dust exposure. The animal data for Ni₃S₂ are fit with a linear model, while the nonlinear animal data for NiO are fit with a Weibull model. The lower 95% confidence limit at a 5% point of departure is used to calculate a tumorigenic potency ratio of Ni₃S₂ to NiO of 5.6. Analyses of actual nickel refinery dust indicate the weight% of Ni₃S₂ and NiO to be 82% and 9%, respectively. This information is used with the previously determined IUR for nickel refinery dust to calculate IUR_NiO = 5.1 × 10^?5 (μg Ni/m³)^?1 and IUR_Ni3S2 = 2.9 × 10^?4 (μg Ni/m³)^?1.