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Sample records for amsco

  1. Activity behavior of the NdNO/sub 3/--HNO/sub 3/--H/sub 2/O--HDEHP--AMSCO System

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, W.G.; Bautista, R.G.

    1978-01-01

    The thermodynamic behavior of the two-phase NdNO/sub 3/--HNO/sub 3/--H/sub 2/O--HDEHP--AMSCO system has been studied to provide experimental data for use with a model to predict the distribution coefficients of neodymium. The nitrate ion activities in the aqueous phase were measured with a nitrate ion selective electrode taking into account the presence of high hydrogen concentration by calibration of the nitrate electrode with nitric acid. The nitrate ion concentration in the organic phase due to the extraction of neodymium complexes by HDEHP was determined by back extraction of the organic phase with 3 M sulfuric acid, diluted and analyzed with a nitrate ion electrode calibrated for different nitrate-sulfate concentration. The amount of the nitrate species extracted into the organic phase increases with increase in the initial neodymium nitrate concentration. The neodymium ion concentration in the organic phase was measured by back extraction with 6 M nitric acid, removal of the neodymium by adsorption with the cation exchange resin, DOWEX 50 x 8 and titration of the neodymium free aqueous phase with NaOH using phenolphtalein as the indicator. The hydrogen ion activity in the equilibrated aqueous phase was determined by direct pH measurements since the polyvalent neodymium ions were found to have very negligible effect on the pH electrode. Vapor pressure measurements to estimate the activity coefficients of the HDEHP dimer resulted in non-reproducible values because of the nonuniform outgassing of the most highly volatile portion of the HDEHP diluent, AMSCO. The activity coefficients of the HDEHP dimer were estimated from the data of Baes who made isopiestic comparisons with triphenylmethane in n-octane as the reference solution assuming that the activity coefficient of triphenylmethane is unity.

  2. Stability of Staphylococcus aureus Phage ISP after Freeze-Drying (Lyophilization)

    OpenAIRE

    Merabishvili, Maia; Vervaet, Chris; Pirnay, Jean-Paul; Vos, Daniel De; Verbeken, Gilbert; Mast, Jan; Chanishvili, Nino; Vaneechoutte, Mario

    2013-01-01

    Staphylococcus aureus phage ISP was lyophilized, using an Amsco-Finn Aqua GT4 freeze dryer, in the presence of six different stabilizers at different concentrations. Stability of the lyophilized phage at 4 degrees C was monitored up to 37 months and compared to stability in Luria Bertani broth and physiological saline at 4 degrees C. Sucrose and trehalose were shown to be the best stabilizing additives, causing a decrease of only 1 log immediately after the lyophilization procedure and showin...

  3. Stability of Staphylococcus aureus phage ISP after freeze-drying (lyophilization.

    Directory of Open Access Journals (Sweden)

    Maia Merabishvili

    Full Text Available Staphylococcus aureus phage ISP was lyophilized, using an Amsco-Finn Aqua GT4 freeze dryer, in the presence of six different stabilizers at different concentrations. Stability of the lyophilized phage at 4 °C was monitored up to 37 months and compared to stability in Luria Bertani broth and physiological saline at 4 °C. Sucrose and trehalose were shown to be the best stabilizing additives, causing a decrease of only 1 log immediately after the lyophilization procedure and showing high stability during a 27 month storage period.