Novel rechargeable battery cells have been constructed using a reduced form of the conducting organic polymer, polyacetylene, as the anode, the inorganic intercalating material, titanium disulfide as the cathode, and either 1.0M LiClO4 in THF or 1.0M NaPF6 in THF as the nonaqueous electrolyte. A feasibility study of the cells is described. It includes constant current discharge characteristics, stability, and rechargeability. The cells exhibited good stability and reversibility. Their performance was cathode limited, owing to the method used for fabricating the TiS2 electrode.

The Majorana Demonstrator is an array of point-contact Ge detectors fabricated from Ge isotopically enriched to 88% in 76 Ge to search for neutrinoless double beta decay. The processing of Ge for germanium detectors is a wellknown technology. However, because of the high cost of Ge enriched in 76 Ge special procedures were required to maximize the yield of detector mass and to minimize exposure to cosmic rays. These procedures include careful accounting for the material; shielding it to reduce cosmogenic generation of radioactive isotopes; and development of special reprocessing techniques for contaminated solid germanium, shavings, grindings, acid etchant and cutting fluids from detector fabrication. Processing procedures were developed that resulted in a total yield in detector mass of 70%. However, none of the acid-etch solution and only 50% of the cutting fluids from detector fabrication were reprocessed. Had they been processed, the projections for the recovery yield would be between 80 -85%. Maximizing yield is critical to justify a possible future ton-scale experiment. A process for recovery of germanium from the acid-etch solution was developed with yield of about 90%. All material was shielded or stored underground whenever possible to minimize the formation of 68 Ge by cosmic rays, which contributes background in the double-beta decay region of interest and cannot be removed by zone refinement and crystal growth. Formation of 68 Ge was reduced by a significant factor over that in natural abundance detectors not protected from cosmic rays.

The adsorption of V (III) on mercury electrodes in thioeyanate electrolytes has been measured chronocoulometrically. The adsorption is not strongly dependent on potential except in the vicinity of the V (III)/V (II) half-wave potential. The adsorbing species is a V(III)-thiocyanate complex containing one or more thiocyanates. The adsorption of V(II) also occurs, but is much weaker than that of V(III). A minimum value for the exchange current for the V(III)/V(II) couple in the adsorbed state has been estimated coulostatically. Although this exchange current is quite large, 0.5 A/cm 2, its magnitude can be largely accounted for by the enhancement of the reactants' surface concentrations produced by their adsorption.The spontaneous adsorption of electrochemical reactants on the surface of electrodes often produces complications in the study of the kinetics of their electrode reactions. An electrode process that can proceed by more than one pathway, e,g., via both the adsorbed and unadsorbed reactants, corresponds to a complex equivalent circuit which contains elements that cannot be evaluated in separate experiments in the absence of the reactants. As a result, a larger number of kinetic parameters must be extracted from the rate data, and confidence in the accuracy and uniqueness of the resulting kinetic parameters is weakened. Under these circumstances, it is advantageous to have independent quantitative information on the extent of adsorption of the reactants because the kinetic data can then be analyzed with one less adjustable parameter.The technique of chronocoulometry (1) is well suited to provide the desired quantitative adsorption data. It has been applied in the present study to evaluate the adsorption of V(III) and V(II) on mercury electrodes in thiocyanate solutions. The V(III)/V(II) system was chosen for several reasons. It offered an opportunity to compare the adsorption of a transition metal redox couple with the extensively studied anioninduced adsorption of white metal cations (2-6) [Cd(II), Zn(II), Pb(II), In(III)]. Second, the equilibrium adsorption of V(III) and V(II) could be measured in poised solutions containing both halves of the redox couple, thus allowing the potential dependence of the adsorption in the vicinity of the half-wave potential to be determined. Analogous data for the white metal cations are less straightforward to obtain because of the difficulties associated with the preparation and storage of metal amalgam electrodes. Finally, the V(III)/V(II) system was attractive because the electrode kinetics of the couple have been extensively studied (7-14) in electrolytes where no reactant adsorption occurs. It was hoped that a comparison of these rates with those measured with adsorbed reactants would contribute to an understanding of the effect of adsorption on the rate of electrochemical charge transfer for a simple redox reaction. ExperimentalTechniques.--The adsorptions of V(III) and V(II) (which shows very little adsorption) were evaluated at potentials removed from the half-wave...

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Phase diagram of the binary ionic liquid 1-ethyl-3- methylimidazolium hexafluorophosphate ([emim][PF6]) - 1- ethyl-2-methylpyrazolium hexafluorophosphate ([empz][PF6]), was determined. The binary system shows a eutectic at 23oC, (which is 38oC below the melting point of the lower melting salt [emim][PF6]), and at the molar composition [emim][PF6]: [empz][PF6] ≈ 47:53. Therefore using the eutectic method a low melting ionic liquid was formed with single salts that contain only small alkyl groups on the cations. At ambient temperature the ionic conductivity of the eutectic mixture is comparable to that of a low melting single salt such as, 1-n-butyl-3- methylimidazolium hexafluorophosphate ([bmim][PF6]), but at higher temperature (e.g. 90oC) the conductivity of the eutectic mixture is 20% higher. This method allows the preparation of purer ionic liquids since the two single salts can be purified by recrystallization, before they are mixed to form the binary system which is a liquid at ambient temperature. Hence the ionic liquids produced by the eutectic method have the potential for finding wider range of applications compared with low melting ionic liquids (single salts) containing longer alkyl groups prepared by the conventional method.