Acid generation potential

As is often the case in CND generating materials (or in low-acid generating potential materials), the detected metal levels in leachates were generally low, in the order of thousandths to hundredths of mg/L. In fact, the Ni concentrations obtained from the fresh waste rocks are often under the detection limit of the ICP-AES employed (0.004 mg/L). For greater appreciation of the environmental behaviour of the different studied waste rocks, particularly to differentiate the geochemical behaviour of fresh and weathered waste rocks, the release rates were calculated. 

S. Ravengai, R. Owen, and D. Love, Evaluation of Seepage and Acid Generation Potential from Evaporation Ponds, Iron Duke Pyrite Mine, Mazowe Valley, Zimbabwe, Phys. Chem. Earth, 29(15-18), 1129-1134 (2004). 

Solids mineral identification mineral abundance cation-exchange capacity (CEC) extractable Mn and Fe oxides soil pR acid-generation potential acid-neutralization capacity... 

FIG. 25 Typical DPSC data for the oxidation of 10 mM bromide to bromine (forward step upper solid curve) and the collection of electrogenerated Br2 (reverse step lower solid curve) at a 25 pm diameter disk UME in aqueous 0.5 M sulfuric acid, at a distance of 2.8 pm from the interface with DCE. The period of the initial (generation) potential step was 10 ms. The upper dashed line is the theoretical response for the forward step at the defined tip-interface separation, with a diffusion coefficient for Br of 1.8 x 10 cm s . The remaining dashed lines are the reverse transients for irreversible transfer of Br2 (diffusion coefficient 9.4 x 10 cm s ) with various interfacial first-order rate constants, k, marked on the plot. (Reprinted from Ref. 34. Copyright 1997 American Chemical Society.)... 

Prediction of acid mine generating potential Validation using... 

Dewatering of the Ruttan tailings offered the opportunity to observe potentially acid generating tailings as they enter oxidizing... 

Like electrophilic addition to diazo compounds [7] from which diazonium ions and, subsequently, carbocations are generated, transition-metal compounds that can act as Lewis acids are potentially effective catalysts for metal carbene transformations. These compounds possess an open coordination site that allows the formation of a diazo carbon-metal bond with a diazo compound and, after loss of dinitrogen, affords a metal carbene (Scheme 5.2). 

Fu X, Mueller DM, Heinecke JW (2002) Generation of Intramolecular and Intermolecular Sulfenamides, Sulfinamides, and Sulfonamides by Hypochlorous Acid A Potential Pathway for Oxidative Cross-Linking of Low-Density Lipoprotein by Myeloperoxidase. Biochemistry 41 1293... 

Klein GW, Bhatia K, Madhavan V, Schuler RH (1975) Reaction of OH with benzoic acid. Isomer distribution in the radical intermediates.) Phys Chem 79 1767-1774 Klein SM, Cohen G, Cederbaum Al (1981) Production of formaldehyde during metabolism of dimethyl sulfoxide by hydroxyl radical generating systems. Biochemistry 20 6006-6012 Kumarathasan P, Vincent R, Goegan P, Potvin M, Guenette J (2001) Hydroxyl radical adduct of 5-aminosalicylic acid a potential marker of ozone-induced oxidative stress. Biochem Cell Biol 79 33-42... 

During the 1970s Shilov published extensively on the reactions of alkanes in aqueous solutions of platinum(II) complexes [3]. The reactions are typically carried out in aqueous hydrochloric acid as solvent at <100°C with chloride salts of Pt(II) as catalyst and the chloride salts of Pt(IV) as the stoichiometric oxidant. Typical reaction yields, based on added methane, are less than 3% with >75% selectivity to methanol and methyl chloride. It was proposed the reaction proceeded via C-H activation to generate alkyl platinum intermediates in reactions with alkanes and later results are consistent with this proposal [4]. This system is one of the first systems proposed to operate via the C-H activation reaction and to generate potentially useful functionalized products. The key disadvantages of the Shilov system were the low rates (catalyst tum-over-frequency, TOF, <10 s ), short catalyst life (turnover-number, TON, <20), and the use of Pt (IV) as a stoichiometric oxidant. 

Noncoded amino-acids Chemical synthesis is not limited to coded amino acids and potentially allows the generation of an infinite variety of nonnatural analogs. 

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