OPTIMIZATION OF MULTISTREAM CASCADES WITH A GIVEN NUMBER OF GAS CENTRIFUGES FOR PURIFICATION OF REGENERATED URANIUM HEXAFLUORIDE FROM 232, 234, 236U

method for optimization of multistream cascades for purification of regenerated ura-nium from even isotopes is improved by using several types of stages with a given number of gas centrifuges. The operating modes of the stages have been determined by the artificial bee colony algorithm

Optimization of the Cascade with Two Additional Product Flows for the Simultaneous Concentration of Intermediate Molybdenum Isotopes

A technique has been developed for optimizing multiflow cascades to obtain highly concentrated intermediate molybdenum isotopes. A computational experiment was carried out to separate a mixture of molybdenum isotopes. Various cases for the separation of molybdenum isotopes in cascades with large step separation coefficients corresponding to gas centrifuges were considered. It is shown that using of the bee swarm optimization has an advantage over the Hook-Jeeves method. © 2020 American Institute of Physics Inc.. All rights reserved

Ordinary Cascades for Purification of Reprocessed Uranium Hexafluoride from 232,234,236U Isotopes

Reprocessed uranium gained from the spent nuclear fuel contains 232,234,236U isotopes within, which considerably hamper its reuse. It is proposed to use an ordinary cascade to reduce the concentration of 232,234U. The output purified from 232,234U is obtained in the cascade waste. The authors analysed the peculiarities of reducing concentration of 236U after the enrichment of reprocessed uranium hexafluoride in terms of 235U in the ordinary cascade and its subsequent dilution. A computational experiment was performed. Parameters of cascade stages were predetermined, which allow to reduce the content of 232,234,236U to an acceptable level. © 2022 Institute of Physics Publishing. All rights reserved

Anodic Dissolution of Non-Ferrous Metals in a Glycerate-Alkali Electrolyte

Studies have been conducted to assess the possibility of refining a lead collector containing precious metals, with the aim of obtaining lead using an economically viable technology. Studied the patterns of anodic oxidation of lead and impurities in alkaline-water-glycerate electrolytes, depending on the concentration of sodium hydroxide and glycerol in the electrolyte, the potential sweep rate. © 2020 Trans Tech Publications Ltd, Switzerland

Production of highly concentrated intermediate molybdenum isotopes in optimal cascade with two additional product flows

The problem of highly concentrated molybdenum isotopes production in multiflow cascades is considered. A method of the cascade with two additional product flows optimization has been developed. Two components intermediate in weight are concentrated simultaneously in those flows. The optimization problem is solved using a variation of the partial flow cuts of the cascade stages with large separation coefficients. The optimization criterion is the minimum of the stage total feed flow while ensuring a given concentration of isotopes. A computational experiment was carried out to separate a mixture of molybdenum hexafluoride. The experiment demonstrated the features of intermediate components concentrating in additional product flows of the cascade. © 2020 Published under licence by IOP Publishing Ltd

Особенности периоперационного ведения пожилых больных при эндоскопическом транссфеноидальном удалении опухолей хиазмально-селлярной области

Nowadays, in the age of rapid introduction of digital and fiber-optic technologies in neurosurgery, a technique for removal of tumors in the chiasmatic-sellar area via an endoscopic transsphenoidal endonasal approach is actively developed; this technique is considered less invasive and is well tolerated by patients, thus permitting to operate patients with somatic complications, as well as the elderly. Taking into account these facts, as well as world statistic data indicating a continuous trend of population aging in developed countries, including Russia, optimization of the perioperative care of elderly patients with a tumor of the chiasmatic-sellar area becomes the problem of highest priority. In order to solve it, this review discusses the basic peculiarities of the perioperative management of elderly patients (characteristics of their somatic status and possible variants of the pre-operational state) with a pathology in the chiasmatic-sellar region; it also presents the modern and most acceptable alternative solutions of this difficult problem (introduction of modern methods of anesthesia, management of the postoperative cognitive dysfunction, postoperative pain syndrome, and postoperative nausea and vomiting). В наши дни, в век бурного внедрения в нейрохирургию цифровых и оптико-волоконных технологий, активно развивается метод удаления опухолей хиазмально-селлярной области эндоскопическим эндоназальным транссфеноидальным доступом, который считается малотравматичным и хорошо переносится больными, в результате чего расширияется возможность оперировать соматически отягощенных больных, а также людей старшей возрастной группы. Учитывая эти факты, а также данные мировой статистики, указывающие на неуклонную тенденцию старения населения в развитых странах, в том числе и в России, оптимизация периоперационного ведения пожилых больных, имеющих опухоль хиазмально-селлярной области, становится наиболее приоритетной задачей. Для ее решения в данной статье рассмотрены основные нюансы периоперационного ведения пожилых больных, имеющих патологию хиазмально-селлярной области: особенности их соматического статуса и возможные варианты их предоперационного состояния. Также представлены современные и наиболее приемлемые альтернативные варианты решения этой непростой проблемы: внедрение современных методик анестезии, борьба с послеоперационной когнитивной дисфункцией, послеоперационным болевым синдромом и послеоперационной тошнотой и рвотой.

Separation of boron isotopes in optimal cascade of uniflow gas centrifuges

Was considered a problem of an optimization of concurrent gas centrifuges for separation of Boron isotopes in form of trifluoride BF3. As the criteria was used a minimum of total number of gas centrifuges upon the given external parameters of the cascades' scheme. The method is based on the analytical relationships for the flows of stages, received under approximating minimization of the total feed flow. Conducted cascade calculations showed that it is possible to obtain BF3 with enrichment up to 99.9 % of 10B in the selection and up to 0.1 % in the waste, which is equivalent to 99.9 % of 11B. © 2020 Published under licence by IOP Publishing Ltd

ПРИМЕНЕНИЕ ДЕКСМЕДЕТОМИДИНА В КАЧЕСТВЕ БАЗОВОГО СРЕДСТВА ДЛЯ АНЕСТЕЗИОЛОГИЧЕСКОГО ОБЕСПЕЧЕНИЯ РАДИОХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ У РЕБЕНКА

This clinical case demonstrates specific features of anesthetic management during radiosurgery in pediatric patients considering the limited access to them during continuous manipulations with pharmacological sedation. Considering the age of the child, dexmedetomidine, the drug from the group of agonists of α2-adrenergic receptors, was used as the main agent. It was used since it could be administred by the noninvasive way for premedication and intravenously in a form of infusion to provide the necessary depth of sedation with preservation of spontaneous breathing and minimization of uncontrolled motions of the patient.Настоящее клиническое наблюдение демонстрирует особенности анестезиологического обеспечения радиохирургического лечения педиатрических пациентов в условиях ограниченного доступа к ним во время длительных процедур с использованием фармакологической седации. Ввиду возрастных особенностей ребенка в качестве базового средства использован дексмедетомидин ‒ препарат из группы центральных α2-адреноагонистов. Его применили благодаря возможности использовать неинвазивно для премедикации и внутривенно в виде инфузии для поддержания необходимой глубины седации с сохраненным самостоятельным дыханием, а также для минимизации самопроизвольных движений пациента