66 research outputs found

    “Green” Extractants in the Recovery Processes of Non-ferrous Metal Ions from Technological Solutions

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    The extraction of non-ferrous metal ions (Co, Ni, Cu, Al) from chloride solutions with poly(propylene glycol) 425 was studied. The values of the distribution coefficients and the degree of metal ions extraction are determined in the system under study. The mechanism of metal extraction in the poly(propylene glycol) 425 – sodium chloride– water extraction system in the presence of KSCN is described. The possibility of selective extraction of Co (II), Ni (II), Cu (II) and Al (III) from chloride solutions with poly(propylene glycol) 425 in the presence of KSCN is shown. Keywords: aqueous two-phase system, metal extraction, liquid–liquid equilibria, e-waste, poly(propylene glycol), sodium chlorid

    Ultrasonic studies of the magnetic phase transition in MnSi

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    Measurements of the sound velocities in a single crystal of MnSi were performed in the temperature range 4-150 K. Elastic constants, controlling propagation of longitudinal waves reveal significant softening at a temperature of about 29.6 K and small discontinuities at \sim28.8 K, which corresponds to the magnetic phase transition in MnSi. In contrast the shear elastic moduli do not show any softening at all, reacting only to the small volume deformation caused by the magneto-volume effect. The current ultrasonic study exposes an important fact that the magnetic phase transition in MnSi, occurring at 28.8 K, is just a minor feature of the global transformation marked by the rounded maxima or minima of heat capacity, thermal expansion coefficient, sound velocities and absorption, and the temperature derivative of resistivity.Comment: 4 pages, 4 figure

    Results and possible prospects of genetic technology in ophthalmology (literature review). Part I

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    The emergence of fundamentally novel technological solutions in the field of gene therapy today, the formation of the priority and the development of genetic technologies create serious prerequisites for the beginning of a new Fusion era in ophthalmology in the near future. This review, in its first part, presents the results of fundamental and clinical studies on the use of viral and non-viral systems for the delivery of genetic material in ophthalmology. The second part of the review will focus on genetic therapeutic strategies (gene replacement, gene suppression, genomic editing using CRISPR / Cas9 technology, priming and transposon editing) that have been used in ophthalmology over the past several years

    Surface state atoms and their contribution to the surface tension of quantum liquids

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    We investigate the new type of excitations on the surface of liquid helium. These excitations, called surfons, appear because helium atoms have discrete energy level at the liquid surface, being attracted to the surface by the van der Waals force and repulsed at a hard-core interatomic distance. The concentration of the surfons increases with temperature. The surfons propagate along the surface and form a two-dimensional gas. Basing on the simple model of the surfon microscopic structure, we estimate the surfon activation energy and effective mass for both helium isotopes. We also calculate the contribution of the surfons to the temperature dependence of the surface tension. This contribution explains the great and long-standing discrepancy between theory and experiment on this temperature dependence in both helium isotopes. The achieved agreement between our theory and experiment is extremely high. The comparison with experiment allows to extract the surfon activation energy and effective mass. The values of these surfon microscopic parameters are in a reasonable agreement with the calculated from the proposed simple model of surfon structure.Comment: 10 pages, 6 figure

    Clinical Features of Visual Disturbances in Leiden Thrombophilia

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    The hereditary thrombophilias is a well-recognized important risk factor for a systemic and local thromboembolic events development. The case of Leiden thrombophilia family inheritance concomitant by the visual disturbances development are shown in this аrticle. Most commonly in hereditary thrombophilias, venous thrombembolias occur, arterial occlusions which have been reported in the recent literature only as individual clinical cases occur more rarely. In the European population hereditary thrombophilias are associated with a prothrombotic mutation in the coagulation factor V gene (Leiden factor) in a greater degree; herewith the risk of thrombotic complications is increasing significantly in homozygous polymorphism forms. Presence of combined mutations in several clotting factors also leads to risk of thrombembolias increase. Consequence of the Leiden mutation is a V activator resistance to the resolving action of the activated protein C which is a natural endogenous anticoagulant protein. Resistance development leads to a deceleration of V factor inactivation and to increasing of the thrombin amount. In the work presented here, development of the consistent bilateralocclusion of the central retinal artery (CRA) in a middle-aged patient with a heterozygous form of Leiden thrombophilia is the subject of interest. Along with the hereditary hemostatic system abnormality, the patient also had cardiovascular risk factors (hypertensive disease, atherosclerosis) which had a potentiating effect on the occlusion development. Taking into account the autosomal dominant nature of the Leiden mutation inheritance, the patient’s only daughter was examined; brief episodes of amaurosis fugax against the background of headaches similar to migraine were detected due to ophthalmological abnormalities. For verification of the Leiden thrombophilia diagnosis, both patients underwent molecular genetic diagnostics. Currently there are no large prospective studies showing the optimal and economically viable approach for identification of thrombophilia genetic polymorphisms in patients with retinal vascular occlusions in daily clinical experience. Possible additional risk factors for thrombembolias development, prevention services for manifest and recurrent vascular occlusions in patients with hereditary blood coagulation system abnormalities and their relatives are discussed in this article

    Optic Nerve Atrophy in Heroin Intoxication

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    Drug dependence is one of important social problems in modern society. It became more actual because of the high morbidity in young working-age patients. The central nervous system is the main target for psychoactive substances. Long-term drug intoxication results in functional and structural brain alterations, it leads to cognitive impairment and disturbances of higher mental functions rendering patients’ disadapted in their work and daily life activities. Eye disorders due to drug abuse are multifaceted and can vary from conjunctival damage to severe endogenous endophthalmitis. Opioid dependence can result not only from intentional self-administration of narcotic drugs, but also from long-term prescribed use of these medicinal products owing to their potent analgesic effect exhibited in somatically ill patients with severe chronic pain. Opioid derivatives act as partial or full agonists of three types of opioid receptors (δ, κ, and µ) extensively expressed by the neurons of the central and, to a lesser extent, peripheral nervous system. The most dangerous complication of intoxication with this group narcotic drugs is opioid induced-respiratory depression resulting in hypoxaemia and hypercapnia. The paper presents a case report of bilateral optic nerve atrophy that developed in a young female patient after a long period of intravenous heroin use. There are practically no reports of optic nerve damage due to heroin intoxication in the current literature. Possible optic nerve atrophy mechanisms under discussion include generalized hypoxia developing against a background of chronic heroin intoxication and direct toxicity of admixtures used to dilute home-made narcotic drugs. In view of the growing use of these substances, physicians have to consider their effects in the differential diagnosis in patients with atypical eye disorders

    ENTERPRISE ARCHITECTURE JSC «RSC «PROGRESS»

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    В работе рассмотрены составляющие компоненты предприятия АО «РКЦ «Прогресс», их взаимодействие, передача информация от отдела к отделу в процессе создания новой модели РН «Союз-5». Работа АО «РКЦ «Прогресс» рассматривается на уровнях производства: Высшее руководство и собрание акционеров, Научно-технический уровень, Уровень проектирования, Конструкторский уровень, Уровень производства и сборки, Уровень заказчика. Каждый уровень детально рассмотрен с точки зрения ответов на вопросы: «Что?»; «Как?»; «Где?»; «Кто?»; «Когда?» и «Почему?». Реализована трехмерная модель. На этапах анализа, проектирования, реализации, использовании и совершенствовании изучено взаимодействие уровней предприятия. Практическое использование проекта заключается в возможности внедрения результатов на предприятии АО «РКЦ «Прогресс», а также других организациях аэрокосмической отрасли. The paper considers the components of the enterprise JSC " RCC "Progress", their interaction, the transfer of information from Department to Department in the process of creating a new model of RN "Soyuz-5". The work of JSC "RCC "Progress" is considered at the levels of production: Senior management and shareholders ' meeting, Scientific and technical level, design Level, Design level, production and Assembly Level, customer Level. Each level is considered in detail from the point of view of the answers to the questions: "What?"; "How?"; "Where?"Who?"; "When? and Why?". Implemented three-dimensional model. At the stages of analysis, design, implementation, use and improvement, the interaction of enterprise levels is studied. The practical use of the project is the possibility of implementing the results at the enterprise of JSC "RCC "Progress", as well as other organizations of the aerospace industry

    Poppers maculopathy as an effect of drug poisoning. A clinical case

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    In recent years, the range of combined narcotic drugs has widened. New chemical modifications  have emerged, including so-called designer drugs, whose action on the body and in particular on the state of vision is increasingly difficult to determine. While the problem of drug abuse is growing drastically, timely detection of a possible toxic damage to the eye induced by drugs and reliable diagnosis differentiating such damage from other etiologies becomes a topical practical issue. The paper presents a clinical case of poppers maculopathy  (poppers being a slang name of aromatic volatile alkyl nitrite compounds). Ophthalmological  manifestations and differential diagnostic criteria of the damage are described. The mechanisms of action and possible treatment methods are discussed
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