Estimation of the activity of lead in the binary Pb-Sb and Pb-Bi systems

The activity of lead in its alloys with bismuth and antimony is estimated by the least squares method and interval analysis. The interval method of processing the experimental results is shown to calculate the reliable ranges of the estimated parameters in the dependences of thermodynamic functions and the actual level of the total measurement errors. © 2013 Pleiades Publishing, Ltd

Активность свинца в его сплаве с сурьмой и висмутом

The present work is devoted to the study of lead thermodynamic activity in the Pb-Sb-Bi alloys. The method for EMF measurements of the concentration cell: (–)Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi)(+) was used. The obtained concentration dependences of the galvanic cell EMF are described by linear equations. The lead activity in the ternary liquid-metal alloy demonstrates insignificant negative deviations from the behavior of ideal solutions.Работа посвящена изучению термодинамической активности свинца в его сплавах с сурьмой и висмутом. Для этого был использован метод измерения э.д.с. концентрационного гальванического элемента: (-)Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi)(+). Полученные концентрационные зависимости э.д.с. гальванического элемента описываются линейными уравнениями. Активность свинца в тройном жидкометаллическом сплаве имеет незначительные отрицательные отклонения от поведения идеального раствора

Anode Processes on Pt and Ceramic Anodes in Chloride and Oxide-Chloride Melts

Platinum anodes are widely used for metal oxides reduction in LiCl–Li2O, however high-cost and low-corrosion resistance hinder their implementation. NiO–Li2O ceramics is an alternative corrosion resistant anode material. Anode processes on platinum and NiO–Li2O ceramics were studied in (80 mol.%)LiCl-(20mol.%)KCl and (80 mol.%)LiCl-(20 mol.%)KCl–Li2O melts by cyclic voltammetry, potentiostatic and galvanostatic electrolysis. Experiments performed in the LiCl–KCl melt without Li2O illustrate that a Pt anode dissolution causes the Pt2+ ions formation at 3.14 V and 550°С and at 3.04 V and 650оС. A two-stage Pt oxidation was observed in the melts with the Li2O at 2.40 ÷ 2.43 V, which resulted in the Li2PtO3 formation. Oxygen current efficiency of the Pt anode at 2.8 V and 650°С reached about 96%. The anode process on the NiO–Li2O electrode in the LiCl–KCl melt without Li2O proceeds at the potentials more positive than 3.1 V and results in the electrochemical decomposition of ceramic electrode to NiO and O2. Oxygen current efficiency on NiO–Li2O is close to 100%. The NiO–Li2O ceramic anode demonstrated good electrochemical characteristics during the galvanostatic electrolysis at 0.25 A/cm2 for 35 h and may be successfully used for pyrochemical treating of spent nuclear fuel. © 2021 Korean Nuclear Society.The present research was partially performed within the Proryv (Breakthrough) project of State Atomic Energy Corporation Rosatom

Phase equilibria and interaction between the CsCl-PbCl2-PbO system components

Thermal analysis was applied to determine liquidus temperatures in the CsCl-PbCl2-PbO system, with the PbO concentration ranging from 0 to 20 mol%. The temperature dependence of the PbO solubility in the CsCl-PbCl2 eutectic melt was studied, and the thermodynamic parameters of the PbO dissolution were calculated. The type, morphology, and composition of oxychloride ionic groupings in the melt were determined in situ using Raman spectroscopy

Screening-diagnostics of bronchial asthma in children at the pre-hospital stage

This article made a study of the practical significance of the survey as a method for the early detection of risk factors for the development of bronchial asthma in children with bronchial obstasctive syndrome.В настоящей статье произведено исследование практической значимости анкетирования как способа раннего выявления факторов риска развития бронхиальной астмы у детей с бронхобстуктивным синдромом

Research and Development of the pyrochemical processing for the mixed nitride uranium-plutonium fuel

A mixed nitride U-Pu SNF pyrochemical reprocessing technology was suggested. It includes the following basic operations: dissolution of key components using the CdCl2 or PbCl2 oxidizer in chloride melt and their subsequent deposition as oxides. The obtained product, which is a mixture of actinides and rare-earth metals, may be additionally purified using hydrometallurgical processes (combined technology) or using pyrochemical methods. The mixture of actinides oxides is reduced to metal ("metallization"), additionally purified from fission products during electrorefining and then Am and Cm are separated using the potentiostatic electrolysis in order to obtain products that may be used for pure fuel fabrication. © 2020 IOP Publishing Ltd. All rights reserved

The Viscosity of Molten Salts Based on the LiF–BeF2 System

Abstract: The temperature dependences of the dynamic viscosity of molten lithium and beryllium fluorides, which are considered as candidate compositions for fuel and coolant of the molten salt reactor (MSR) burner of long-lived actinides from spent nuclear fuel of a VVER 1000/1200 (pressurized water reactor), were obtained by rotational viscometry using an FRS 1600 high-temperature rheometer (Anton Paar, Austria). Molten salt mixtures 0.66LiF–0.34BeF2 and (0.73LiF–0.27BeF2) + UF4 containing 1 and 2 mol % UF4 were studied with regard to the intermediate and fuel circuits of the MSR. The salt mixtures were prepared by direct melting of components and certified using X-ray phase and elemental analyses. The shear rate parameter was selected according to the viscosity curves obtained in the melts at a temperature of 700°C. It was found that the viscosity does not depend on the shear rate in the range of γ = 6–20 s–1. When measuring the temperature dependence of viscosity, the γ value was 11 s–1. The experimentally obtained values of the viscosity of the LiF–BeF2–UF4 melts in the temperature range from liquidus to 800°C are described by the linear equation log η = a + b/t, but their temperature coefficients differ noticeably, which indicates a significant dependence of the viscosity of these melts on composition and temperature. The obtained viscosity values for the 0.66LiF–0.34BeF2 melt agree with the available published data within 7–10% in the temperature range of 650–750°C. With an increase in the LiF content, the viscosity of the melt decreases: it is 20% lower in the 0.73LiF–0.27BeF2 melt at t = 650°C. However, when 2 mol % UF4 is added, the viscosity of the fuel salt 0.73LiF–0.27BeF2 + UF4 increases by 10% at the same temperature. © 2022, Allerton Press, Inc

Lead activity in Pb-Sb-Bi alloys

Работа посвящена изучению термодинамической активности свинца в его сплавах с сурьмой и висмутом. Для этого был использован метод измерения э.д.с. концентрационного гальванического элемента: (–)Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi)(+). Полученные концентрационные зависимости э.д.с. гальванического элемента описываются линейными уравнениями. Активность свинца в тройном жидкометаллическом сплаве имеет незначительные отрицательные отклонения от поведения идеального раствора

Lead Activity in Pb-Sb-Bi Alloys

Работа посвящена изучению термодинамической активности свинца в его сплавах с сурьмой и висмутом как модели при переработке отходов, образующихся как при производстве металлов (дроссы, съемы, пыли, шламы), так и при выработке готовых изделий (свинцовые аккумуляторы). Для этого был использован метод измерения э. д. с. концентрационного гальванического элемента: (-)Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi)(+). Полученные концентрационные зависимости э.д.с. гальванического элемента описываются линейными уравнениями. Активность свинца в тройном жидкометаллическом сплаве имеет незначительные отрицательные отклонения от поведения идеального раствора. Методом э.д.с. измерены равновесные потенциалы сплавов Pb-Sb-Bi в расплаве KCl-PbCl2 (50-50 мол. %) для широкой области составов в интервале температур от 450 до 630 °С. Рассчитана термодинамическая активность свинца в системе свинец-сурьма-висмут. Показано, что свинец проявляет незначительные отрицательные отклонения от поведения идеальных растворов.The present work is devoted to the study of lead thermodynamic activity in the Pb-Sb-Bi alloys. The method for EMF measurements of the concentration cell: (-)Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi)(+) was used. The obtained concentration dependences of the galvanic cell EMF are described by linear equations. The lead activity in the ternary liquidmetal alloy demonstrates insignificant negative deviations from the behavior of ideal solutions. Activity lead in ternary liquid metal alloy has a slight negative deviation from ideal behavior of the solution. Method of the EMF measured potentials of equilibrium alloys Pb-Sb-Bi melt KCl-PbCl2 50-50 mol. %) for a wide range of compounds in the temperature range from 450 to 630 °C