High-Temperature Electrochemical Refining of Secondary Lead

The present chapter is devoted to the analysis of the obtained data on the high-temperature electrolytic production of high-purity lead from secondary lead in chloride melts. Kinetic parameters of electrode reactions were calculated, and the sequences of the metal dissolution from the double lead-antimony (Pb-Sb), lead-bismuth (Pb-Bi), and antimony-bismuth (Sb-Bi) alloys were determined. A long-term electrolysis of the antimony (battery scrap), bismuth (lead-bismuth), and lead-containing raw materials in the electrolytic cell of original construction with a porous ceramic diaphragm impregnated with the eutectic KCl-PbCl2 chloride electrolyte was performed. The anode lead alloy, containing 57.0 wt% of antimony and 36.0 wt% of bismuth, and cathode grade lead were obtained as a result of the electrolysis. The values of lead, antimony, and bismuth separation coefficients were calculated according to the values of the equilibrium potentials of the Pb-Sb, Pb-Bi, and Sb-Bi alloys. The values of separation coefficients were found to be 6.5·106–1.5·108 for a single stage at the lead extraction from the Pb-Sb and Pb-Bi alloys, which proves the possibility of a highly effective lead extraction. The value of Sb-Bi alloy separation coefficient ranges from 5.5 to 6.5, which testifies the complexity and low effectiveness of the separation process. An electrolytic refining of lead-bismuth and secondary lead, obtained from the battery scrap, was performed

Molecular Dipolar Crystals as High Fidelity Quantum Memory for Hybrid Quantum Computing

We study collective excitations of rotational and spin states of an ensemble of polar molecules, which are prepared in a dipolar crystalline phase, as a candidate for a high fidelity quantum memory. While dipolar crystals are formed in the high density limit of cold clouds of polar molecules under 1D and 2D trapping conditions, the crystalline structure protects the molecular qubits from detrimental effects of short range collisions. We calculate the lifetime of the quantum memory by identifying the dominant decoherence mechanisms, and estimate their effects on gate operations, when a molecular ensemble qubit is transferred to a superconducting strip line cavity (circuit QED). In the case rotational excitations coupled by dipole-dipole interactions we identify phonons as the main limitation of the life time of qubits. We study specific setups and conditions, where the coupling to the phonon modes is minimized. Detailed results are presented for a 1D dipolar chain

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

Electrode processes during the electrorefiniment of lead in the KCl-PbCl2-PbO melt

The influence of PbO addition on current efficiency during the electrorefinement of lead in the KCl-PbCl2-PbO melt was investigated. It was shown that with PbO concentration in the KCl-PbCl2 eqiumolar mixture increasing, the current efficiency of lead decreases. Electrode processes mechanism is proposed

Quantum phase transition in a two-dimensional system of dipoles

The ground-state phase diagram of a two-dimensional Bose system with dipole-dipole interactions is studied by means of quantum Monte Carlo technique. Our calculation predicts a quantum phase transition from gas to solid phase when the density increases. In the gas phase the condensate fraction is calculated as a function of the density. Using Feynman approximation, the collective excitation branch is studied and appearance of a roton minimum is observed. Results of the static structure factor at both sides of the gas-solid phase are also presented. The Lindeman ratio at the transition point comes to be $\gamma = 0.230(6)$. The condensate fraction in the gas phase is estimated as a function of the density.Comment: 4 figures v.3 One citation added, updated Fig.4. Minor changes following referee's and editor's comment

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

<i>N,N</i>-bis-(dimethylfluorosilylmethyl)amides of <i>N</i>-organosulfonylproline and sarcosine: synthesis, structure, stereodynamic behaviour and <i>in silico</i> studies

(O→Si)-Chelate difluorides R3R2NCH(R1)C(O)N(CH2SiMe2F)2 (9a–c, R1R2 = (CH2)3, R3 = Ms (a), Ts (b); R1 = H, R2 = Me, R3 = Ms (c)), containing one penta- and one tetracoordinate silicon atoms were synthesized by silylmethylation of amides R3R2NCH(R1)C(O)NH2, subsequent hydrolysis of unstable intermediates R3R2NCH(R1)C(O)N(CH2SiMe2Cl)2 (7a–c) into 4-acyl-2,6-disilamorpholines R3R2NCH(R1)C(O)N(CH2SiMe2O)2 (8a–c) and the reaction of the latter compounds with BF3·Et2O. The structures of disilamorpholines 8a,c and difluoride 9a were confirmed by an X-ray diffraction study. According to the IR and NMR data, the O→Si coordination in solutions of these compounds was weaker than that in the solid state due to effective solvation of the Si–F bond. A permutational isomerisation involving an exchange of equatorial Me groups at the pentacoordinate Si atom in complexes 9a–c was detected, and its activational parameters were determined by 1H DNMR. In silico estimation of possible pharmacological effects and acute rat toxicity by PASS Online and GUSAR Online services showed a potential for their further pharmacological study

Анализ влияния геометрических отклонений рабочих лопаток вентилятора на аэродинамические характеристики ступени

In this article there are the results of the aerodynamic characteristic calculations for the fan blades of the gas turbine engine for the regional aircraft, considering production deviations. The analyzed models of blades with different geometric airfoil deviations, the calculated model of the fan stage, the estimated aerodynamic characteristics are described. Here you can find the example of the calculation results.En este artículo se presentan los resultados de los cálculos de las características aerodinámicas para las aspas del ventilador del motor de turbina de gas para un avión regional, teniendo en cuenta las desviaciones de producción. Asimismo, se describen los modelos analizados de aspas con diferentes desviaciones geométricas de perfil aerodinámico, el modelo calculado de la etapa del ventilador y las características aerodinámicas estimadas. A su vez, los resultados del cálculo se ilustran con un ejemplo.Neste artigo são apresentados os resultados dos cálculos das características aerodinâmicas das pás do ventilador do motor de turbina de gás para um avião regional, tendo em conta os desvios de produção. Além disso, são descritos os modelos analisados de lâminas com diferentes desvios geométricas de perfil aerodinâmico, o modelo calculado da fase do ventilador e as características aerodinâmicas estimadas. Por sua vez, os resultados do cálculo são ilustrados com um exemplo.Представлены результаты расчета аэродинамических характеристик лопаток вентилятора газотурбинного двигателя для регионального самолета с учетом производственных отклонений. Описаны анализируемые модели лопаток с различными геометрическими отклонениями на пере, расчетная модель ступени вентилятора, оцениваемые аэродинамические характеристики, приведен пример результатов расчета

Electrolytic refining of lead in molten chloride electrolytes

Three types of antimony and bismuth electrolytic cells to be used for lead electrorefining were developed and tested. The electrolytic cell with the bipolar metallic electrode, the electrolytic cell with two anodes and one cathode, and the electrolytic cell with the porous diaphragm were studied. The tests demonstrated that lead is effectively separated from the metallic impurities in all constructions. Grade lead may be obtained at the cathode, and lead-antimony and lead-bismuth alloys may be produced at the anode. The electrolytic cell with a porous diaphragm was found to double the production rate and greatly decrease the electrical potential of the cell as compared to the other two constructions. © IJTech 2017