Polyaniline—Graphene Electrodes Prepared by Electropolymerization for High-Performance Capacitive Electrodes: A Brief Review

Both polyaniline (PANI) and graphene are widely studied for their application as capacitive electrodes in energy storage devices. However, although PANI can be easy synthesized, is of low cost and has a higher specific capacitance than graphene, pristine PANI electrodes do not present long-term stability due to their large volume changes during release/doping of the electrolyte ions and surface area reduction with charge-discharge cycling. That is why a combination of PANI with carbonaceous materials, especially conductive and high-surface-area graphene as well as more widely used reduced graphene oxide (rGO), provides an effective approach to solve these problems. At the same time, the electropolymerization process is one of the possible methods for synthesis of PANI composites with G or rGO as freestanding electrodes. Therefore, no binders or additives such as carbon black or active carbon need to be used to obtain PANI/rGO electrodes by electrochemical polymerization (EP), in contrast to similar electrodes prepared by the chemical oxidative polymerization method. Thus, in this paper, we review recent advances in EP synthesis of PANI/rGO nanocomposites as high-performance capacitive electrode materials, combining the advantages of both electrical double-layer capacitance of rGO and pseudocapacitance of PANI, which hence exhibit long cycle life and high specific energy.publishe

Comment on “Hole-pinned defect-dipoles induced colossal permittivity in Bi doped SrTiO3 ceramics with Sr deficiency”

With this contribution, as a comment to the publication in Journal of Materials Science & Technology 44 (2020) 54, reporting giant dielectric response, structural characterization and numerical simulations in Sr1-1.5xBixTiO3 ceramics, we show that the reported results are rather contradicting and not well analysed, while the suggested mechanism for the giant permittivity response is not valid or doubtful and has to be reconsidered. Moreover, many details and data are missing making impossible not only to call the obtained results very suitable for practical application but even to reproduce them.publishe

THE EFFICACY OF ERADICATION OF SMALL INTESTINAL BACTERIAL OVERGROWTH IN PATIENTS WITH NON-ALCOHOLIC FATTY LIVER DISEASE

Background. Emerging evidence suggests a strong interaction between the gut, gut microbiota and liver. Derangement of gut flora, particularly small intestinal bacterial overgrowth (SIBO), occurs in a large percentage of patients with non-alcoholic fatty liver disease (NAFLD) and plays an important role in its pathogenesis. Aim. Study of the frequency of SIBO in various forms of non-alcoholic fatty liver disease, as well as the possibilities of its pathomorphosis as a result of eradication of SIBO as a result of the use of rifaximin or multicomponent probiotic. Material and methods. There were investigated 125 patients with non-alcoholic fatty liver disease (70 men, 55 women aged 18 to 65 years, mean age 37±6.7 years) developed at obesity or type 2 diabetes mellitus, including 85 patients with liver steatosis (group1) and 40 patients with non-alcoholic steatohepatitis (group 2). Patients with concomitant SIBO (70 patients) was treated with rifaximin or multicomponent probiotic. As the main endpoints of the study, the frequency of achieving eradication of SIBO was evaluated (estimated from the results of a repeated H2-lactulose hydrogen test after treatment), as well as a decrease in the severity of liver steatosis by steatometry and a decrease / normalization of transaminase levels 3 months after the start of the treatment. Secondary endpoints included the change in BMI and the HOMA-IR index 3 months after the start of the treatment. Results. SIBO in patients with non-alcoholic fatty liver disease was significantly more frequent than in control (p <0.005), and in patients with non-alcoholic steatohepatitis – significantly more often than in patients with liver steatosis (80 % vs 47.1 %, P <0.01). Eradication of SIBO after use of rifaximin was recorded in 30 of 36 patients with non-alcoholic fatty liver disease (83.3 %), including 16 of 20 patients with steatosis (80 %) and 14 of 16 (87.5 %) patients with non-alcoholic steatohepatitis. In the group of patients taking multicomponent probiotics after treatment, eradication of SIBO was noted in 12 of 36 patients (33.3 %), including 7 patients with steatosis (35 %) and 5 patients (31.3 %) with non-alcoholic steatohepatitis Conclusion. The investigation shows that the eradication of small intestinal bacterial overgrowth has the positive influence on the natural course of NAFLD and use of rifaximine should be discussed as a perspective therapeutic strategy at this patholog

Low-Temperature Dielectric Response of Strontium Titanate Thin Films Manipulated by Zn Doping

The voltage dependence of the dielectric permittivity ε' and the low dielectric loss tanδ of incipient ferroelectrics have drawn vast attention to the use of these materials for the development of tuning elements in electronics and telecommunications. Here, we study the DC electric field dependence of low-temperature ε' in ~320 nm thick sol-gel-derived SrTi1-xZnxO3-δ thin films with x = 0.01 and 0.05, deposited on Pt/TiO2/SiO2/Si substrates. Incorporation of Zn onto Ti sites is found to decrease ε' compared to undoped SrTiO3 films, while increasing the relative tunability nr up to ~32.9% under a DC electric field of 125 kV/cm at low temperatures. The hysteresis-free variation in ε' with electric field and tanδ values below 0.6% observed for SrTi1-xZnxO3-δ film with x = 0.01 make this compound more attractive for tunable device applications.publishe

Professional diplomatic language in the Ukrainian-British and Ukrainian-German international agreements at the turn of the XX – XXI centuries

The paper analyzes the peculiarities of the use of the professional language of diplomacy in the Ukrainian-German and Ukrainian-British agreements at the turn of the XX - XXI centuries. International relations is a sphere of social activity in which language is formed in the diplomatic professional field. Diplomatic protocol requires compliance with certain rules and regulations.The objective of the study is to highlight the main components of the professional language of diplomacy based on the analysis of diplomatic texts of interstate agreements. An important element is the interpretation of diplomatic ideas through the prism of the linguistic dimension. The paper is not just a linguistic analysis of the text, but a comparative analysis of the key elements of the diplomatic style of speech, typical for the Ukrainian-German and Ukrainian-British agreements. A combination of dialectical and synergetic scientific and philosophical methodology was successfully used to achieve the set tasks. Due to the structural and typological methods of linguistic research, the tasks set for the classification of diplomatic texts have been achieved.Thus, the study of the components of professional diplomatic language is relevant in modern scientific and linguistic discourse, as it enables studying philological aspects and at the same time is useful for understanding the essence of international politics

Процеси фазоутворення в надрешітці Pd/Fe та їх вплив на електрофізичні властивості

В результаті проведених досліджень фазового складу плівкової системи на основі Pd/Fe було встановлено, що в дво- і багатошарових плівках при осадженні, внаслідок конденсаційно-стимульованої дифузії, формується неупорядкована структура з ГЦК-PdFe фазою

Процеси фазоутворення, електрофізичні та гальваномагнітні властивості багатошарових плівкових систем Pd/Fe

Розвиток магнітоелектроніки і сенсорного приладобудування тісно пов’язаний із пошуком нових функціональних матеріалів у вигляді магнітонеоднорідних багатошарових плівок, мультишарів та гранульованих сплавів. Плівкові системи на основі феромагнітних (Fe, Co) і парамагнітних (Pd, Pt) шарів – це цікаві об’єкти з точки зору їх практичного використання для створення носіїв інформації з високою щільністю магнітного запису, елементів магніто-оптичних систем та спінової електроніки [1-4]. При формуванні таких приладових систем особлива увага приділяється стабільності робочих характеристик під дією різних фізичних полів (температури, деформації та магнітного поля). Оскільки в багатошарових плівках і мультишарах суттєву роль відіграють розмірні ефекти, то змінюючи кількість фрагментів і товщину окремих шарів, можна отримувати плівкові матеріали з наперед заданими електричними і магнітними параметрами. Особливості фізичних властивостей систем Pd/Fe обумовлені також тим фактом, що Pd, будучи парамагнітним елементом, за наявності феромагнетика (наприклад, атомів Fe) проявляє феромагнітні властивості. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/2637

Introduction of Innovative Technologies and Methods of ICT Competency Building of Scientific-Pedagogical Staff Under the COVID-19 Pandemic: Preconditions and Challenges of Future Education System (Ukrainian Experience)

The article considers the problem of the formation of innovative ICT-competence of scientific and pedagogical staff against the background of the implementation of quarantine measures to counteract the COVID-19 epidemic. Particular attention is paid to the content and goals of ICT-competence. The structure of its components is highlighted and the peculiarities of its functioning to ensure research and educational processes during the pandemic and to overcome its consequences are analyzed. Particular attention is paid to the prerequisites for the rapid formation of ICT competence in times of crisis. The features of the process of computerization and digitalization of the academic sphere in the world and Ukraine are analyzed and highlighted. The article analyzes the main trends and vectors of innovative ICT-competence development, notes its current and future goals and objectives

Проблеми забезпечення національної стійкості України в умовах повномасштабної війни

Мета роботи: виявлення закономірностей та ключових факторів стійкості України в умовах збройного повномасштабного вторгнення з боку Російської Федерації. Метод дослідження: аналізу та синтезу подій в Україні. Результати дослідження: виявлено ключові фактори національної стійкості. Теоретична цінність дослідження: результати дослідження доповнюють вже існуючі теоретичні дослідження в сфері національної стійкості, а також дозволили сформувати ключові фактори національної стійкості шляхом аналізу реальних подій в умовах війни, яка за масштабами перевершила всі військові конфлікти на європейському континенті після Другої Світової Війни. Практична цінність дослідження: в межах дослідження наведені практичні заходи уряду та громадян України, а також країн-партнерів, які дозволили зберегти українську державність і чинити ефективний опір агресії з боку Російської Федерації