Експериментальні дослідження електричних машин. Частина V. Синхронні машини

В навчальному посібнику викладено підходи до експериментальних досліджень синхронних машин. Для кожного виду дослідження відведено відповідне лабораторне заняття, наведено основні теоретичні відомості, задачі для самостійного розв’язування, програмі лабораторних робіт і методичним вказівкам для їх виконання. Запропоновані способи досліджень дозволяють охопити основні питання для закріплення теоретичних знань з відповідного розділу дисципліни «Електричні машини». Навчальний посібник рекомендовано для студентів, що навчаються за напрямками 6.050702 «Електромеханіка», 6.050701 – «Електротехніка та електротехнології»В учебном пособии изложены подходы к экспериментальным исследованиям синхронных машин. Для каждого вида исследования отведено соответствующее лабораторное занятие, приведены основные теоретические сведения, задачи для самостоятельного решения, программе лабораторных работ и методическим указаниям для их выполнения. Предложенные способы исследований позволяют охватить основные вопросы для закрепления теоретических знаний по соответствующему разделу дисциплины «Электрические машины». Учебное пособие рекомендовано для студентов, обучающихся по направлениям 6.050702 «Электромеханика», 6.050701 - «Электротехника и электротехнологии

Options for safe antibiotic treatment for acute otitis media in children

Acute otitis media in children is a relevant health care and social problem conditioned by the high incidence of the inflammatory disease in early and middle childhood. Otitis media is often accompanied by impaired hearing function, and when it becomes chronic, there is a risk of hearing loss. Moreover, deafness in childhood results in speech disorders and socialization problems. [1

Thin film GaP for solar cell application

International audienceA new approach to the silicon based heterostructures technology consisting of the growth of III-V compounds (GaP) on a silicon substrate by low-temperature plasma enhanced atomic layer deposition (PE-ALD) is proposed. The basic idea of the method is to use a time modulation of the growth process, i.e. time separated stages of atoms or precursors transport to the growing surface, migration over the surface, and crystal lattice relaxation for each monolayer. The GaP layers were grown on Si substrates by PE-ALD at 350°C with phosphine (PH3) and trimethylgallium (TMG) as sources of III and V atoms. Scanning and transmission electron microscopy demonstrate that the grown GaP films have homogeneous amorphous structure, smooth surface and a sharp GaP/Si interface. The GaP/Si heterostructures obtained by PE-ALD compare favourably to that conventionally grown by molecular beam epitaxy (MBE). Indeed, spectroscopic ellipsometry measurements indicate similar interband optical absorption while photoluminescence measurements indicate higher charge carrier effective lifetime. The better passivation properties of GaP layers grown by PE-ALD demonstrate a potential of this technology for new silicon based photovoltaic heterostructur

TRANSRADIAL APPROACH DURING PERCUTANEOUS CORONARY INTERVENTIONS. PART 2. PRACTICAL GUIDELINES AND THE AUTHORS’ DATA

The paper describes the technical features of a transradial approach; indications and patient selection for this arterial approach; and stepwise patient preparation. It depicts the anatomic variants of the origin of the radial artery, which affect the success of this approach. The suitable instruments for this approach are described. The authors give their results of the performed study comparing different types of approaches

TRANSRADIAL APPROACH DURING PERCUTANEOUS CORONARY INTERVENTIONS. PART 1. EVIDENCE BASE FOR APPLYING A TRANSRADIAL APPROACH

The use of the radial artery as an approach to percutaneous coronary interventions is becoming increasing popular now. The success of this approach depends on both the accumulated experience of an operator and a health care facility. The paper analyzes an investigation of the comparative characteristics of both a transradial approach and a transfemoral one and the impact of the former on the success of the procedure. It considers the role of the transradial approach in the present-day practice of X-ray endovascular diagnosis and treatment specialists and discusses the problems of education and choice of optimal clinical indications

ENDOVASCULAR TREATMENT FOR CHRONIC CORONARY OCCLUSIONS IN PATIENTS WITH CORONARY HEART DISEASE

Objective: to analyze the angiographic results of endovascular treatment for chronic coronary occlusions in patients with coronary heart disease.Material and methods. In 2009 to 2013 attempted endovascular recanalization of chronic coronary occlusions in 854 patients with coronary heart disease. The patients’ age ranged from 36 to 68 years (mean 52 years). The estimated duration of occlusion was 1 month to more than 3 years. There were 193 (22.6%) females and 661 (77.4%) males. 462 (54.1%) patients had a history of myocardial infarction. 738 (86.4%) and 116 (13.6%) patients had true (TIMI grade 0) and functional (TIMI grade 1) occlusions, respectively. Multi- and univascular lesions were found in 683 (79.9%) and 171 (20.1%) patients, respectively. Silent occlusions with preserved myocardial contractility were identified in 165 (19.3%) patients.Results. Blood flow could be successfully restored in 616 (72.1%) patients. Recanalization of chronic coronary occlusion failed in 238 (27.9%) patients.Conclusion. Recanalization of chronic coronary occlusions is a highly effective and relatively safe technique. The efficiency of the procedure largely depends on the duration of occlusion, its X-ray morphological characteristics, and the experience of a physician

ОСОБЕННОСТИ ФОРМИРОВАНИЯ ПОРИСТЫХ СТРУКТУР НА ОСНОВЕ ДИОКСИДА КРЕМНИЯ И ОКСИДОВ МЕТАЛЛОВ ЗОЛЬ–ГЕЛЬ–МЕТОДАМИ

The formation of porous structures in sol−gel systems based on silicon oxide and metal oxides, i.e. cobalt and tin, has been studied. We show that the investigation of metal oxide nanomaterials by the thermal desorption method allows developing the optimum process conditions for obtaining patterns having the highest specific surface area.Рассмотрены особенности формирования пористых структур в золь−гель−системах на основе диоксида кремния и оксидов металлов, таких как кобальт и олово. Показано, что исследование металлооксидных наноматериалов методом тепловой десорбции позволяет выработать технологические режимы получения образцов с наибольшей удельной поверхностью