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Molten oxide electrolysis (MOE) is an electrometallurgical technique that enables the direct production of metal in the liquid state from oxide feedstock (1,2), and compared with traditional methods of extractive [...]

A novel polymeric superabsorbing composite was prepared using the graft copolymerization of acrylic acid (AANa, 70% neutralization with NaOH) and 2-acryla-mido-2-methyl propane sulfonic acid (AMPS) onto the hydroxyethyl cellulose (HEC) [HEC-g-P(AANa-co-AMPS)], which was initiated by means of a glow-discharge electrolysis plasma rather than a chemical initiator. The composite material was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA). We obtained absorbencies of 2490 g [g.sup.-1] for distilled water and of 109 g [g.sup.-1] for 0.9 wt% NaCl solution. Results show that the maximum adsorption capacities for Ni(II), Cu(II), Cd(II), Pb(II), and Hg(II) from aqueous solution were 974.84, 975.43, 1535.52, 1970.47, and 1879.53 mg [g.sup.-1], respectively. The adsorption isotherm followed the Langmuir isotherm model very well. Adsorption kinetics results indicate that the fast adsorption rate followed the pseudo-second-order kinetics equations. POLYM. ENG. SCI., 52:2217-2227, 2012. © 2012 Society of Plastics Engineers, INTRODUCTION The removal of heavy metal ions from aqueous solutions is a very important subject in environmental pollution because the enrichment of heavy metal ions in the human body can [...]

Research was conducted to examine the efficacy of electrolyzed oxidizing water for inactivating Escherichia coli O157:H7, Salmonella enteritidis and Listeria monocytogenes with a view to its potential application to foods and food contact surfaces as an antimicrobial treatment. Results suggest that electrolyzed oxidizing water may be a useful disinfectant. However, appropriate applications have to be validated.

The electrochemical oxidation and reduction of anthracene (AN) and thianthrene (TH) incorporated within pentasil and mordenite zeolites in the presence of H20 showed a distinctive pattern. This indicated that the electrochemically generated radical ions located at the outermost layers of the zeolite particles experienced an effective protection against the attack of external reagents. This effect was believed to arise from some degree of spatial constraints experienced by the guests adsorbed on the surface of microporous solids, suggesting partial penetration through pore entrances.

A study was conducted to analyze a way of preparing cyclopropanone N,O-acetals using an electrochemical method and a number of transformations of the resulting products under acidic conditions. Electrolyses were performed in a divided cell using a platinum anode. The enamines were electrolyzed under a constant current until the 2F/mol of charge had passed through the cell. Moreover, 1H and 13C nuclear magnetic resonance spectra were obtained at 90 and 22.4 MHz, respectively.

The ab initio molecular orbital method was used in studying the oxidation of dimethylamine borane (DMAB) as a reductant for an electroless deposition process. Reactions through three-coordinate borane molecules or through five-coordinate ones by primary addition of OH- were investigated. Electroless deposition is used in creating metal thin films by reducing metal ions in electrolytes. Results indicated that the five-coordinate compounds are transition states while the five-coordinate molecules have bipyramidal structures.

A study was conducted to analyze neutral metallocenes using the constant current electrolytic nature of electrospray ionization mass spectrometry. Several polymeric metallocenes were also examined in solution and solid-state studies to determine answers to concerns about mass and charge transport mechanisms. Results indicated the feasibility of using the constant-current electrolytic nature of electrospray ionization mass spectrometry to readily produce charged analytes supporting more than two charges per molecule.

A study was conducted to analyze the voltammetric characteristics of transition metal complexes of 2,2'-bipyridine, (M(bipyridine)3)(ClO4)2(M = Co(super II), Fe(super II), and Ru(super II)), in toluene/acetonitrile mixtures using cyclic voltammetry. Experimental results indicated that the reduction current related to square wave voltammetric experiments increased linearly with the C60 concentration between the range of 0.25 - 20 micron.

Research was conducted to examine the electrooxidative inter- and intramolecular carbon-carbon bond formation using organothio groups as electroauxiliaries. The objective was to show that the anodic oxidation of alpha-organothio-substituted ethers in the presence of carbon nucleophiles leads to the bond formation. Results demonstrate the generality of the concept of electroauxiliary and its possible use in the control of stereochemistry.

Nitrous oxide reductase ([N.sub.2]OR) is a dimeric copper-dependent bacterial enzyme that catalyzes the reduction of [N.sub.2]O to [N.sub.2] as part of the denitrification pathway. In the absence of an x-ray crystal structure, the current model of the nature of the copper sites within the enzyme is based on four copper atoms per monomer and assigns two copper atoms to an electron transfer center, [Cu.sub.A], a bis-thiolate-bridged dinuclear copper center found to date only in [N.sub.2]OR and cytochrome c oxidase, and two copper atoms to a second dinuclear center, Cuz, presumed to be the site of catalysis. based on detailed analysis of the low temperature magnetic CD spectra of [N.sub.2]OR, this paper revises the current model and proposes that both [Cu.sub.A] and [Cu.sub.z] are variants of an electron transfer center and hence that all of the observed optical features are due to this electron transfer center. It is proposed further that the presence of these different forms provides a mechanism for the delivery of two electrons to an active site comprising copper ions lacking thiolate coordination.

A study was conducted to analyze the mechanism of electrohydrodynamic convection in thin-layer electrolytic cells. The explicit finite differences method was utilized to determine the differential equations characterizing the transport processes. The driving force density for the convection was analyzed from the distribution of the electric field. Experimental results indicated that the recombination of rubrene radicals complicated the evaluation of the electric field distribution in the interelectrode space.

Some of the views of Steven E. Jones, et al, regarding a study on excess heat and helium-4 production during electrolysis of the Pd/D2O + LiOD system invite comment. The claims that faradaic efficiencies less than 100% can support excess heat in cold fusion cells is not valid. The anomalous effects in deuterated metals were determined by results of calorimetric studies. However, the authors' criticisms on radiation monitoring may be valid even though it was not a major focus of the study.

Rubber was produced by placing rubber latex between two electrodes between which an external voltage was maintained. The thickness of the rubber deposited on the anode was measured as a function of time of electrolysis, voltage applied across the electrodes and distance between the electrodes. based on the observed dielectric responses of rubber obtained through the electrolysis process, an electrical model of conductance and complex capacitance elements linked in parallel is proposed, indicating the additive nature of the individual responses in the system. Electrical representation of rubber obtained by simple drying however showed two different models. Natural rubber was found to have all the elements connected in parallel while that of vulcanized rubber was found to have a series connection of a pair of parallel connected conductance and capacitance elements.

Research was conducted to examine the voltammetric oxidation of solution and solid phases of salts of (V/(CO)6-) in aqueous (electrolyte) media. The starting material was sodium diglyme and stabilized salt and experiments were confined to the potential region associated with the process. Results indicate that V(CO)6 in solution reacts with water as well as with oxygen. However, the product of electrochemical oxidation reacts slowly with water but very rapidly with oxygen on the voltammetric time scale.

Research was conducted to examine the mechanistic aspects of the electrocatalytic oxidative cleavage of 1,2-diols by electrogenerated Pb(IV). Voltammetric data derived by both channel flow cell and rotating disk electrode experiments are examined using numerical simulation. Results reveal the importance of the structural features of the diols in modifying the ligand sphere of the intermediate Pb(IV) metal complex, thereby shifting the sensitive preequilibria for this highly fluxional system.

The kinetic and mechanistic properties of the oxidation of three hexosamines, D-mannosamine, D-glucosamine and D-galactosamine by CAB in alkaline medium at 40 degrees C are presented. Results indicate that oxidation occurs through the cleavage of both C-H and C-C bonds to form a mixture of aldonic acids from the hexosamines. Based on experimental data, a new pathway for the oxidation of hexosamines by CAB is proposed.

The scientific and commercial implications of methanol fuel cells have sparked interest in methanol electrochemical oxidation. Thus, a study was conducted on formaldehyde formed from methanol electrochemical oxidation through sensitive fluorescence assay of methanol samples on platinum. The presence of formaldehyde was measured in 6 minute electrolysis periods. The findings demonstrate that the formaldehyde accounted for 30% of the total electrolysis charge at 0.2 and 0.4 volts. The data provided insights on methanol electrochemistry and oxidation pathways.

A study was conducted on CH3C(O)S. radical formation upon one electron oxidation of acetyl thiolate CCH3C(O)S- in aqueous solutions. One-electron oxidation of CH3C(O)S- ions produced CH3C(O)S. radicals. The radical subsequently underwent beta-fragmentation to form CH3. and COS with a rate constant of 6.6x104 S- at room temperature. The experimental data for the kinetics and thermochemical properties of CH3-C(O)SH and CH3C(O)S. radicals obtained in this work were then compared with those of the PhC(O)SH and PhC(O)S. radicals.

A single irreversible cyclic voltammetric wave that corresponds to the two-electron cleavage of the carbon-halogen bond was observed for each compound in the electrochemical reduction of several mono- and dihalothiophenes at carbon cathodes in dimethylformamide containing tetramethylammonium perchlorate. The reduction of dihalothiophenes exhibited a stepwise trend.The first stage of the reduction involves two-electron cleavage of one carbon-halogen bond to yield mixtures of mono- and dihalothiophenes, while the second stage corresponds to an overall four-electron process to give thiophene. An electrolytically induced halogen dance appear to generate product distributions during electrolyses.

Carbon-carbon (C-C) bond-forming reactions in microemulsions and in DMF were investigated. The Co(I)L complex vitamin B12 mediated the reactions of alkyl iodides with 2-cyclohexen-1-one and the cyclization of 2-(4-bromobutyl)2-cyclohexen-1-one to 1-decalone. The Co(I)L complex reacted with alkyl halides to produce a Co-alkyl complex. A comparison of the C-C bonds formed following the cleavage of the Co-alkyl complexes revealed wide variations in selectivity. The cyclization reaction in a microemulsion gave remarkable stereoselectivity in comparison with the other reactions.

The use of microsecond pulsed deposition to achieve anodic oxidation of YBa2Cu3O(7-x) thin films at room temperature is investigated. Specifically, currents of up to 15.2 A were applied to oxygen-deficient thin films in aqeous solution at five kilohertz for a period of 1.3 microsecond. The procedure, which enhanced the oxygen stoichiometry of the films, restored the superconducting capabilities and modified the microstructure of the films.

Examination of the electrophilic addition of bromine to benzonorbornadiene at different temperatures reveals that at low temperatures the addition reaction produces 2-eno-7-anti-dibromide, while the reaction at higher temperatures produces non-arranged and rearranged products in a ratio of 8:2. Presence of a free radical inhibitor inhibits the formation of non-arranged products, revealing a competition between radical and ionic reactions. Benzonorbornadiene on electrolysis produces 2,7-disubstituted benzonorborn-5-ene derivatives.

The continuity of the liquid and gaseous states, and the existence of critical temperatures for specific gases, was discovered by Thomas Andrews in 1861. This had important implications for the liquefaction of the supposedly 'permanent' gases and the creation of an important new industry. Currently, the chemistry of reactions in supercritical fluids, especially water, is the subject of much research, especially in the context of treating industrial waste.

Introduction of silver into a silicate glass often leads to reduction and coloration. The electron required for silver reduction is extracted from a nonbridging oxygen atom. The use of high-field-strength ions limits the number of nonbridging oxygens and silver reduction.

An analysis of a-Si thickness as affecting thermal annealing in terms of the resistance to oxidation and self-aligning silicidation features in the a-Si and Ti bilayer process is presented. Ti metal with a thickness of 500 Angstroms is used with the process window reduced. Reaction with limited diffusion and accumulation of excess oxygen waste in the silicide layer allow the Ti-film thickness to affect the formation sequence during the silicide phase. Process window size is found to increase in direct proportion to increases in Ti film thickness.

The anodic oxidation of aryl substituted ketene imines takes a course nearly opposite that of the analogous chemical-based process. In the presence of protons, almost quantitative amounts of amides are formed. As the condition becomes increasingly dry, the amide yield gives way to bicyclic, tricyclic and tetracyclic dimerization and trimerization products, along with the formation of stable carbocations. Several possible mechanisms, including intramolecular radical and electrophilic attacks to effect ring closure or formation, are discussed.

The synthesis of alpha-acetoxy-3,3,3-trifluoropropyl sulfides provides the material for a study of their nucleophilic substitution reactions at the beta position. Acetoxylation is achieved by electrochemical means under very high substrate and electrolyte strengths. The subsequent study shows that nucleophilic attack on the beta position, otherwise difficult because of sulfur's stabilization of the nearby carbocation, proceeds efficiently with the use of electrogenerated acids rather than ordinary Lewis acids.

Sodium benzophenone in solution allows controlled room-temperature reduction of three perfluorocycloalkanes to perfluoro and polyfluoro aromatics. Other perfluorocycloalkanes either are overreduced or yield low reduction products, with substrates bearing tertiary carbons being the most reactive. Electrochemical studies show that selectivity and reaction rates are determined by the reduction potentials of the substrate, the reducing agent and the product. Optimum results are obtained when the reduction potential decreases in that order.

The utilization of Mg cathodes and the addition of proton donors such as t-BuOH and t-BuOD can lead to the electrolytic reduction of aliphatic carboxylic acids in the methyl ester and N,N-dimethylamide forms. The introduction of t-BuOH and t-BuOD results in the production of primary alcohols and 1,1-dideuterated alcohols in excellent yields, respectively. The process can be used effectively in the electroreduction of different esters of aliphatic carboxylic acids.

The transient changes in stripe patterns of Ag-Sb thin films electrodeposited from the aqueous electrolyte are investigated. The surface morphology observation indicates that the stripe patterns are represented by average stripe spacings and have a time-invariant property.

The effect of a static magnetic field, B, on the electrolysis of copper in aqueous solution is investigated. The linear sweep voltammetry, impedance spectroscopy, chronoamperometry, rotating disk voltammetry, and analysis of fractal growth patterns are used for the purpose.

The rutile form of titania ([TiO.sub.2) possesses unique electronic characteristics that enable ifs use in a number of applications, including gas sensors. Porous characteristics of rutile-based systems have shown to [...]

Reactions under Mitsunobu conditions and alkaline hydrolysis help convert galvinol into a galvinol-substituted alkanethiol, which is characterized by spectroscopic studies. Electrochemical studies reveal the formation of monolayers on gold electrodes upon exposure of these electrode to ethanol solutions of the alkane thiol. Cyclic voltammetric study of these electroactive monolayers shows that they undergo oxidation through a one-electron/one-proton process, producing a radical-terminated monolayer.