a Processing sulfur containing minerals is one of the biggest sources of acute anthropogenic pollution particularly in the form of acid mine drainage. This study attempts to show an innovative method for processing sulfide-based minerals. It is shown that pyrite can be solubilised by both electrochemical oxidation and reduction in a deep eutectic solvent (DES) Ethaline, a mixture of choline chloride and ethylene glycol.A novel method is demonstrated to investigate the redox properties of minerals using a paste made from the mineral powder in a DES. The first bulk electrochemical dissolution of pyrite is shown without the formation of H 2 S or SO 2 . It is also shown that the soluble species, including elements such as arsenic, can be recovered electrochemically which could potentially decrease acid mine drainage. The electrochemical properties of other iron-sulfur and iron-arsenic minerals are also presented and compared to those of pyrite.

The Atomic Force Microscope (AFM) is capable of imaging fingerprint ridges on polished brass substrates at an unprecedented level of detail. While exposure to elevated humidity at ambient or slightly raised temperatures does not change the image appreciably, subsequent brief heating in a flame results in complete loss of the sweat deposit and the appearance of pits and trenches. Localized elemental analysis (using EDAX, coupled with SEM imaging) shows the presence of the constituents of salt in the initial deposits. Together with water and atmospheric oxygen--and with thermal enhancement--these are capable of driving a surface corrosion process. This process is sufficiently localized that it has the potential to generate a durable negative topographical image of the fingerprint. AFM examination of surface regions between ridges revealed small deposits (probably microscopic "spatter" of sweat components or transferred particulates) that may ultimately limit the level of ridge detail analysis.

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Here we report that the Deep Eutectic Solvent (DES), (Ethylene glycol) 2 (Choline chloride), (2Eg:ChCl)is an effective medium in electrolytic removal of the Fe rich layer from Ni based Hot Isostatic Press (HIP) consolidation and that it is capable of sustaining etching at higher rates and at higher current efficiencies than a comparable aqueous electrolyte formulated from methane sulphonic acid / glycolic acid (MSA/GA). At high etch rates the surface finish is not as good using 2Eg:ChCl but high etch rates, current efficiency and excellent surface finish can be obtained from a 90%/10% hybrid mixture of 2Eg:ChCl MSA/GA electrolytes. In this study we have set out to compare the electropolishing and bulk electrolytic etching of HIP formed bodies fabricated from RR1000 Ni based superalloys in aqueous methane sulphonic acid / glycolic acid (MSA/GA) electrolyte and in Deep Eutectic Solvent (DES) type ionic liquids. Samples consisting of HIP formed test coupons were electropolished under a range of conditions of current density and applied potential in either the DES (2Eg:ChCl) or MSA/GA electrolytes. The samples were then characterised using a combination of methods including scanning electron microscopy (SEM), atomic force microscopy (AFM) and optical microscopy. Surface roughness and etch characteristics of the samples were determined after treatment in each of the electrolytes in order to establish the comparative efficacy of the DES. Here we present details of some of the challenges and methodologies as well as characterisation of model test pieces and forms using the scale-up facilities at the Ionic Liquids Demonstrator (ILD) facility at the University of Leicester.We show that the HIP alloy can be effectively removed under mild conditions using DES electrolytes that are of low toxicity, environmentally sustainable, relatively low cost and without the use of strong acids or chemical etchants.

Here we introduce a new concept for synthesising molecularly imprinted nanoparticles by using proteins as macro-functional monomers. For a proof-of-concept, a model enzyme (HRP) was cross-linked using glutaraldehyde in the presence of glass beads (solid-phase) bearing immobilized templates such as vancomycin and ampicillin. The cross-linking process links together proteins and protein chains, which in the presence of templates leads to the formation of permanent target-specific recognition sites without adverse effects on the enzymatic activity. Unlike complex protein engineering approaches commonly employed to generate affinity proteins, the method proposed can be used to produce protein-based ligands in a short time period using native protein molecules. These affinity materials are potentially useful tools especially for assays since they combine the catalytic properties of enzymes (for signaling) and molecular recognition properties of antibodies. We demonstrate this concept in an ELISA-format assay where HRP imprinted with vancomycin and ampicillin replaced traditional enzyme-antibody conjugates for selective detection of templates at micromolar concentrations. This approach can potentially provide a fast alternative to raising antibodies for targets that do not require high assay sensitivities; it can also find uses as a biochemical research tool, as a possible replacement for immunoperoxidase-conjugates.