On Determinants of Euro-Dollar Rates : An Empirical Study by DOLS

© 2015 Springer Science+Business Media New York. Characteristics of the wave disturbances of the ionospheric electron number density were measured using the Kharkov incoherent scatter radar. The disturbance generation accompanied the SURA heating of the near-Earth plasma by high-power periodic radiation. The distance between the heater and the radar was about 960 km. The possibility of generating ionospheric wave disturbances with a period of 20 to 30 min in the internal gravity wave range was confirmed. The disturbance propagation velocity was near 320–400 m/s, and the relative amplitude of the electron density variation was 1–10%. The wave disturbances appeared in the altitude range 145–235 km. Aperiodic bursts of the electron number density with a relative amplitude of up to 5–10% were detected after the first switch-ons of periodic radiation in the 30-min heating — 30-min pause regime at altitudes of 145 to 310 km. The observation results generally conform to the synchronous observation data obtained using the Kharkov vertical-sounding Doppler radar and a network of ionosondes

ACTOPROTECTOR ACTIVITY OF 4-R-(IDENEAMINO)- 5-R-4Н-1,2,4-TRIAZOLE-3-THIOLS

In this study, actoprotector activity of 1,2,4-triazole derivatives is described. The biological activity of synthetic 4-R-(ideneamino)-5-R-4Н-1,2,4-triazole-3- thiols was analyzed. The forced swim test with a weight load of 10% of the test animal’s body weight was applied. According to the obtained results, compounds that contained NH4+ and CuSO4 substituents were among the most active, potency of which was close to that of the reference drug Riboxin. Introduction of propylamine, isopropylamine and piperazine groups into the molecule decreases the actoprotector activity. Compounds containing monoethanolamine, diethylamine, ethylamine, and magnesium sulfate moieties almost did not exhibit actoprotector activity.In this study, actoprotector activity of 1,2,4-triazole derivatives is described. The biological activity of synthetic 4-R-(ideneamino)-5-R-4Н-1,2,4-triazole-3- thiols was analyzed. The forced swim test with a weight load of 10% of the test animal’s body weight was applied. According to the obtained results, compounds that contained NH4+ and CuSO4 substituents were among the most active, potency of which was close to that of the reference drug Riboxin. Introduction of propylamine, isopropylamine and piperazine groups into the molecule decreases the actoprotector activity. Compounds containing monoethanolamine, diethylamine, ethylamine, and magnesium sulfate moieties almost did not exhibit actoprotector activity

Синтез похідних 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тіадіазолу

Aim. To conduct the synthesis and confirm the structure of 3-methyl-6-R-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives as potential biologically active compounds.Results and discussion. It has been shown that the heterocyclization reaction of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol with carboxylic acids in the excess of phosphorus oxychloride yields 3-methyl-6-R-[1,2,4]-triazolo[3,4-b][1,3,4]thiadiazoles.Experimental part. The reaction of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol with the corresponding carboxylic acids was carried out in the excess of phosphorus oxychloride. The mixture was heated for 5 h with subsequent cooling and neutralization to pH 7 using ammonia solution. 1H NMR spectra of the compounds synthesized were recorded on a Varian Mercury VX-200 spectrometer operating at a frequency of 200 MHz, in DMSO-d6, using tetramethylsilane (TMS) as an internal standard. Melting points were measured using a MPA100 device. The elemental analysis was performed on a Elementar Vario EL Cube elemental analyzer. Agilent 1260 Infinity HPLC System equipped with Agilent 6120 mass spectrometer were used for registering LC-MS data.Conclusions.As a result of this study 10 new compounds of the 3-methyl-6-R-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole series have been obtained. The structure and purity of the products have been confirmed using 1Н NMR spectroscopy, LC-MS and elemental analysis. Received: 18.02.2020Revised: 29.04.2020Accepted: 29.05.2020Цель. Синтезировать и подтвердить структуру производных 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тиадиазола – потенциальных биологически активных соединений.Результаты и их обсуждение. Показано, что взаимодействие 4-амино-5-метил-4H-1,2,4-триазол-3-тиола с карбоновыми кислотами в присутствии избытка оксихлорида фосфора протекает с образованием 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тиадиазолов.Экспериментальная часть. Взаимодействие 4-aмино-5-метил-4H-1,2,4-триазол-3-тиола с карбоновыми кислотами проводили в избытке оксихлорида фосфора при нагревании в течении 5 часов с последующим охлаждением и нейтрализацией до pH 7 раствором аммиака. 1H ЯМР-спектры синтезированных соединений были записаны на спектрометре Varian Mercury VX-200, рабочая частота – 200 MГц, в ДМСО-d6, с использованием тетраметилсилана (TMS) в качестве внутреннего стандарта. Температуры плавления измеряли с помощью устройства MPA100. Элементный анализ выполняли на элементном анализаторе Elementar Vario EL Cube. Система HPLC Agilent 1260 Infinity с масс-спектрометром Agilent 6120 использована для регистрации LC-MS-данных.Выводы. В результате исследования синтезированы 10 новых соединений из ряда производных 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тиадиазола. Структура и чистота соединений подтверждены методами 1Н ЯМР-спектроскопии, LS-MS и элементным анализом.Received: 18.02.2020Revised: 29.04.2020Accepted: 29.05.2020Мета. Синтезувати та підтвердити структуру похідних 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тіадіазолу – потенційних біологічно активних сполук.Результати та їх обговорення. Показано, що взаємодія 4-аміно-5-метил-4H-1,2,4-триазол-3-тіолу з карбоновими кислотами у присутності надлишку фосфору оксихлориду перебігає з утворенням 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тіадіазолів.Експериментальна частина. Взаємодію 4-aміно-5-метил-4H-1,2,4-триазол-3-тіолу з карбоновими кислотами проводили у надлишку фосфору оксихлориду при нагріванні впродовж 5 годин з подальшим охолодженням та нейтралізацією до pH 7 розчином амоніаку. 1H ЯМР-спектри синтезованих сполук було записано на спектрометрі Varian Mercury VX-200, робоча частота – 200 MГц, в ДМСО-d6, з використанням тетраметилсилану (TMS) як внутрішнього стандарту. Температури плавлення вимірювали за допомогою пристрою MPA100. Елементний аналіз виконували на елементному аналізаторі Elementar Vario EL Cube. Систему HPLC Agilent 1260 Infinity з мас-спектрометром Agilent 6120 використано для реєстрації LC-MS-даних.Висновки. В результаті дослідження синтезовано 10 нових сполук з ряду похідних 3-метил-6-R-[1,2,4]триазоло[3,4-b][1,3,4]тіадіазолу. Структуру та чистоту синтезованих сполук підтверджено методами 1Н ЯМР-спектроскопії, LS-MS та елементним аналізом.Received: 18.02.2020Revised: 29.04.2020Accepted: 29.05.202

Synthesis of β-SiC in the intermediate layer of corundum coatings based on a sol-gel binder for protecting graphite objects from oxidation

A coating is developed for protecting graphite from oxidation at 2023 – 2223 K. The efficiency of the protective action of a corundum coating based on a sol-gel binder increases due to creating a dense intermediate layer between the graphite substrate and the coating as a result of its self-reinforcement with fibers of mullite crystals and -SiC nanoparticles. Components of a modifier and sol-gel binder, but not carbon of the graphite substrate, provide synthesis of β-SiC