ВЛИЯНИЕ ДИЭЛЕКТРИЧЕСКОГО БАРЬЕРА НА РАСПРЕДЕЛЕНИЕ ЭЛЕКТРИЧЕСКОГО ПОЛЯ В ВЫСОКОВОЛЬТНОЙ КОМПОЗИТНОЙ ИЗОЛЯЦИИ ЭЛЕКТРИЧЕСКИХ МАШИН

Introduction. Modern high-voltage systems for composite insulation of electrical machines consist of tape glass mica paper materials (dry or pre-impregnated). The electrical characteristics of a multilayer composite insulation system are determined by both the fractional content of the individual components and their electrophysical properties. Purpose. The analysis of the influence of electrophysical characteristics and thickness (fraction) of the dielectric barrier on the distribution of the electric field in the composite high-voltage insulation of electrical machines. Methodology. Simulation of surface charge accumulation at the interface between the substrate and the dielectric barrier is based on the Maxwell–Wagner theory for interfacial polarization. Practical value. The influence of the electrophysical characteristics and thickness of the dielectric barrier on the distribution of the electric field has been established. In the steady state, the electric field strength in the dielectric barrier exceeds the average value by 50 %. In the region of small transition times (up to 1 s), the relative dielectric constant of the barrier has a significant effect on the distribution of the electric field. The use of a dielectric barrier with a higher dielectric constant and fractional content in comparison with the substrate leads to an increase in electric field strength by 5 % relative to the average value in composite insulation. Experimental studies of the long-term electrical strength of glass mica-belt ribbons in the cured (thermosetting) state are consistent with the simulation results. Composite insulation based on glass fiber mica tape with a high content of the mica barrier and fiberglass of smaller thickness has (8-16) % higher values of long-term electric strength. Представлены результаты распределения электрического поля в высоковольтной композитной изоляции на основе предложенной математической модели накопления поверхностного заряда на границе раздела подложка – барьер. В установившемся режиме напряженность электрического поля в диэлектрическом барьере может превышать среднее значение на 50 % в зависимости от электрофизических характеристик и толщины компонентов. Показано, что в области малых времен переходного процесса на характер распределения электрического поля влияют как относительная диэлектрическая проницаемость, так и толщина диэлектрического барьера. Экспериментальная проверка выполнена для пяти типоразмеров стеклослюдобумажной ленты по 5-ть макетов в каждой. Установлено, что композитная изоляция с повышенным содержанием слюдинитового барьера и стеклотканью меньшей толщины имеет на (8-16) % более высокие значения длительной электрической прочности.

Simplified mathematical modeling of the distribution process of licuroside and glycyram between the extractant and Glycyrrhizae radices

Theoretical development of the extraction process is an important task for further modeling and calculation of optimal conditions for extraction of biologically active compounds from the plant raw material. The aim of the study was to propose and test a theoretical model to describe the process of Licuroside and Glycyram distribution between the solid phase of Glycyrrhiza radices and the extractant. For studies, we used Glycyrrhiza radices (Liquorice roots). For extraction, we used plant raw material with particle size of 0.1-0.5 mm, and ethanol-water solution 70 % v/v was used as an extractan

Evaluating deliberative dialogues focussed on healthy public policy

Background: Deliberative dialogues have recently captured attention in the public health policy arena because they have the potential to address several key factors that influence the use of research evidence in policymaking. We conducted an evaluation of three deliberative dialogues convened in Canada by the National Collaborating Centre for Healthy Public Policy in order to learn more about deliberative dialogues focussed on healthy public policy. Methods: The evaluation included a formative assessment of participants’ views about and experiences with ten key design features of the dialogues, and a summative assessment of participants’ intention to use research evidence of the type that was discussed at the dialogue. We surveyed participants immediately after each dialogue was completed and again six months later. We analyzed the ratings using descriptive statistics and the written comments by conducting a thematic analysis. Results: A total of 31 individuals participated in the three deliberative dialogues that we evaluated. The response rate was 94% (N = 29; policymakers (n = 9), stakeholders (n = 18), researchers (n = 2)) for the initial survey and 56% (n = 14) for the follow-up. All 10 of the design features that we examined as part of the formative evaluation were rated favourably by all participant groups. The findings of the summative evaluation demonstrated a mean behavioural intention score of 5.8 on a scale from 1 (strongly disagree) to 7 (strongly agree). Conclusion: Our findings reinforce the promise of deliberative dialogues as a strategy for supporting evidence-informed public health policies. Additional work is needed to understand more about which design elements work in which situations and for different issues, and whether intention to use research evidence is a suitable substitute for measuring actual behaviour change

Phytochemical, microbiological, and technological studies in the field of obtaining a hydroalcoholic extract with antimicrobial activity from the liquorice root

Phytochemical composition and antimicrobial activity of hydroalcoholic extracts from the liquorice root with the use of different concentrations of ethanol have been studied. The optimal range of ethanol concentration of 65±15% v/v has been found. The dependency between the integral index of antimicrobial activity of the extract and concentration of glycyram and licuroside has been foun

The atomic structure of large-angle grain boundaries Σ5\Sigma 5 and Σ13\Sigma 13 in YBa2Cu3O7−δ{\rm YBa_2Cu_3O_{7-\delta}} and their transport properties

We present the results of a computer simulation of the atomic structures of large-angle symmetrical tilt grain boundaries (GBs) $\Sigma 5$ (misorientation angles \q{36.87}{^{\circ}} and \q{53.13}{^{\circ}}), $\Sigma 13$ (misorientation angles \q{22.62}{^{\circ}} and \q{67.38}{^{\circ}}). The critical strain level $\epsilon_{crit}$ criterion (phenomenological criterion) of Chisholm and Pennycook is applied to the computer simulation data to estimate the thickness of the nonsuperconducting layer ${\rm h_n}$ enveloping the grain boundaries. The ${\rm h_n}$ is estimated also by a bond-valence-sum analysis. We propose that the phenomenological criterion is caused by the change of the bond lengths and valence of atoms in the GB structure on the atomic level. The macro- and micro- approaches become consistent if the $\epsilon_{crit}$ is greater than in earlier papers. It is predicted that the symmetrical tilt GB $\Sigma5$ \theta = \q{53.13}{^{\circ}} should demonstrate a largest critical current across the boundary.Comment: 10 pages, 2 figure

Glutamate Concentration in the Serum of Patients with Schizophrenia

Glutamate is the major neurotransmitter with multiple functions in the central nervous system. Glutamate-mediated excitotoxicity is involved in the pathophysiological processes in schizophrenia. The purpose of this study was to determine the concentration of glutamate in the serum of patients with paranoid schizophrenia compared with healthy individuals, and depending on the duration of the schizophrenic process and leading clinical symptoms. We investigated the level of glutamate in the serum of 158 patients with paranoid schizophrenia and 94 healthy persons. Higher concentrations of glutamate in schizophrenic patients compared with healthy persons have been found. The maximum concentrations of glutamate were detected in patients with disease duration of more than ten years. Glutamate level in the serum does not depend on the prevailing negative or positive clinical symptoms. The increased concentration of glutamate can hypothetically contribute to dopaminergic and glutamatergic imbalance, leading to the development of psychotic symptoms and cognitive dysfunction

Особливості перебігу окиснювальних процесів у щурів, уражених тетрахлорометаном на тлі інтоксикації карбофосом

Topicality. The chemical pollution of environment and its impact on the human body is one of the problems not fully studied. It is a question of priority. Carbon and tetrachloride malathion are the most dangerous contaminative elementsconsidered to be the risk factors for many environmentally dependent diseases. Therefore, it is actual to study the characteristics and mechanisms of the aforementioned xenobiotics combined action on the body.Aim. To investigate the free radical processes activity and the endogenous markers of intoxication at the conditions of effect on the rats organism by tetrachloride bbeing affected by malathion.Materials and methods. Experiments conducted on white rats being under carbon tetrachloride intoxication influence (4th, 7th days of the affection) on the basis of thirtieth days malathion affection . Rats were taken out of the experimentby the thiopental anesthesia.Results and discussion. The experimental data proved the malathion and carbon tetrachloride toxic effect, which increases by the conditions of their combined using.Conclusions. It was established, that the maximum activation of free radical processes and deepening endogenous intoxication observed on the seventh day affection by the carbon tetrachloride on on the basis of thirtieth days malathion intoxication. Актуальность. Проблема влияния химического загрязнения окружающей среды на организм человека является одной из приоритетных и до конца не изученных. Среди загрязнителей большую угрозу представляют тетрахлорметан и карбофос – факторы риска многих экологически зависимых болезней. Поэтому изучение особенностей и механизмов комбинированного влияния вышеупомянутых ксенобиотиков на организм является актуальным.Целью работы было изучение активности свободнорадикальных процессов и маркеров эндогенной интоксикации при воздействии на организм крыс тетрахлорметана и карбофоса.Материалы и методы. Эксперименты проведены на белых крысах, которые подвергались интоксикации тетрахлорметаном (4-ые, 7-е сутки поражения) на фоне тридцатидневного поражения карбофосом. Крыс выводили из эксперимента под тиопенталовым наркозом.Результаты и их обсуждениe. Экспериментальные данные подтвердили токсическое влияние карбофоса и тетрахлорметана, которое усиливается при условии их комбинированного применения. Это подтверждаетсяактивацией свободнорадикальных процессов и углублением эндогенной интоксикации, максимальное развитие которой наблюдалось на седьмые сутки поражения тетрахлорметаном на фоне тридцатидневной интоксикации карбофосом.Выводы. Доказано, что максимальная активация свободнорадикальных процессов и углубление эндогенной интоксикации наблюдались на седьмые сутки поражения тетрахлорметаном на фоне тридцатидневной интоксикации карбофосом.Актуальність. Проблема впливу хімічного забруднення навколишнього cередовища на організм людини є однією з пріоритетних та не до кінця вивчених. Серед забруднювачів значну загрозу становлять тетрахлорометан та карбофос - фактори ризику виникнення багатьох екологічно залежних хвороб. Тому вивчення особливостей та механізмів комбінованої дії вищевказаних ксенобіотиків на організм є актуальним. Метою роботи було дослідження активності вільнорадикальних процесів та маркерів ендогенної інтоксикації за умов впливу на організм щурів тетрахлорометану на тлі ураження карбофосом.Матеріали та методи. Експерименти проведені на білих щурах, які піддавались інтоксикації тетрахлорометаном (4-та, 7-а доба ураження) на тлі тридцятиденного ураження карбофосом. Щурів виводили з експерименту під тіопенталовим наркозом.Результати та їх обговорення. Експериментальні дані підтвердили токсичний вплив карбофосу та тетрахлорометану, який підвищується за умов їх комбінованого застосування.Висновки. Встановлено, що максимальна активація вільнорадикальних процесів та поглиблення ендогенної інтоксикації спостерігаються на сьому добу ураження тетрахлорометаном на тлі тридцятиденної інтоксикації карбофосом

Poly[di-μ2-aqua-μ5-(pyridine-2,6-dicarboxyl­ato)-μ3-(pyridine-2,6-dicarboxyl­ato)-cobalt(II)disodium]

In the title compound, [CoNa2(C7H3NO4)2(H2O)2]n, the CoII atom is coordinated by two pyridine N atoms and four carboxyl­ate O atoms from two doubly deprotonated pyridine-2,6-dicarboxyl­ate ligands in a distorted octa­hedral geometry. One Na+ cation is coordinated by three carboxyl­ate O atoms and two water mol­ecules and the other is coordinated by five carboxyl­ate O atoms and two water mol­ecules in an irregular geometry. The bis­(pyridine-2,6-dicarboxyl­ato)cobalt complex units are connected by Na+ cations and bridging water mol­ecules into a three-dimensional coordination network. O—H⋯O hydrogen bonds are formed between the water mol­ecules and the carboxyl­ate O atoms

All solvable extensions of a class of nilpotent Lie algebras of dimension n and degree of nilpotency n-1

We construct all solvable Lie algebras with a specific n-dimensional nilradical n_(n,2) (of degree of nilpotency (n-1) and with an (n-2)-dimensional maximal Abelian ideal). We find that for given n such a solvable algebra is unique up to isomorphisms. Using the method of moving frames we construct a basis for the Casimir invariants of the nilradical n_(n,2). We also construct a basis for the generalized Casimir invariants of its solvable extension s_(n+1) consisting entirely of rational functions of the chosen invariants of the nilradical.Comment: 19 pages; added references, changes mainly in introduction and conclusions, typos corrected; submitted to J. Phys. A, version to be publishe