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Tag Archive for Мазур

J Therm Anal Calorim, 2017

M. Brusnikina, O. Silyukov, M. Chislov, T. Volkova, A. Proshin, A. Mazur, P. Tolstoy, I. Terekhova

“Effect of cyclodextrin complexation on solubility of novel anti-Alzheimer 1,2,4-thiadiazole derivative”

J Therm Anal Calorim, 2017
DOI: 10.1007/s10973-017-6252-1

источник: https://link.springer.com/journal/10973

New 1,2,4-thiadiazole derivative displaying neuroprotective potential and high activity in the treatment of Alzheimer’s disease has been synthesized. The objective of this study was to improve the aqueous solubility of this drug-like compound by means of complex formation with native and hydroxypropylated β-cyclodextrins. To this end, aqueous solubility of 1,2,4-thiadiazole derivative was investigated in the presence of β-cyclodextrins. It was shown that the phase solubility diagrams are of Bs type demonstrating the initial increase in thiadiazole solubility in solutions of cyclodextrins (concentration up to 0.01 mol kg−1) followed by a solubility decrease due to the precipitation of the complexes formed. In comparison with β-cyclodextrin, hydroxypropyl-β-cyclodextrin displays more pronounced solubilizing action since it forms more stable complexes with thiadiazole. Solid complexes of 1,2,4-thiadiazole derivative with β-cyclodextrins were prepared by grinding and freeze-drying methods. DSC, TG, hot-stage microscopy, solid-state 13C MAS CP/TOSS NMR, powder X-ray diffractometry and FTIR spectroscopy were used to prove the existence of complexes in the solid state. Solubility of the obtained formulations was also examined. It was found that complexes of thiadiazole with hydroxypropyl-β-cyclodextrin exhibited higher solubility in phosphate buffer (pH 7.4) compared with pure thiadiazole and its complexes with β-cyclodextrin.

Applied Catalysis: A, 2017, 542, 350-358

P. Mäki-Arvela, J. Zhu, N. Kumar, K. Eränen, A. Aho, J. Linden, J. Salonen, M. Peurla, A. Mazur, V. Matveev, D. Y. Murzin

“Solvent-free “green” amidation of stearic acid for synthesis of biologically active alkylamides over iron supported heterogeneous catalysts”

Applied Catalysis: A, 2017, 542, 350-358
DOI: 10.1016/j.apcata.2017.06.006

Stearoyl ethanolamine was synthesized by amidation of stearic acid with ethanolamine in solventless conditions. Iron containing heterogeneous catalysts supported on SiO2, Al2O3, Beta (BEA), ZSM-12 (MTW) and Ferrierite (FER) were used in this work. Sn-modified Ferrierite and H-Ferrierite were also studied for comparison. Fe-modified catalysts synthesized using solid state ion-exchange and evaporation impregnation methods, were thoroughly characterized with X-ray powder diffraction, scanning electron microscope, FTIR with pyridine, nitrogen adsorption, energy dispersive X-ray microanalysis and Mössbauer spectroscopy. The highest conversion was obtained with Fe-H-FER-20 at 140 °C in 1 h giving 61% conversion and 98% selectivity towards the desired amide. The catalytic performance in terms of turnover frequency per mole of iron was achieved with the catalyst exhibiting the largest amount of Fe3+ species, optimum acidity and a relatively low Brønsted to Lewis acid site ratio.

Известия РАН. Серия физическая, 2017, том 81, 344–348

Т. Н. Тарасенко, З. Ф. Кравченко, В. В. Бурховецкий, А. С. Мазур, В. И. Каменев, А. И. Линник

“Синтез, микроструктура, сложный характер магнитного состояния слаболегированного висмутом манганита лантана”

Известия РАН. Серия физическая, 2017, том 81, № 3, с. 344–348
DOI:10.7868/S036767651703036X

Проведены структурные, магнитные и резонансные исследования манганитов BixLa1 – xMnO3. Золь–гель-методом получены нанопорошки слаболегированных составов (x = 0.0–0.1) с размером частиц ≤40 нм. При спекании в одинаковых условиях средний размер гранул резко растет с ростом содержания Bi. Спектры ЯМР манганитов твердофазного синтеза 55Mn отвечают условию быстрого обмена Mn4+ ↔ Mn3+. Измерение магнитной восприимчивости обнаружило неоднородность магнитного состояния системы BixLa1 – xMnO3.

 

«МРТ взгляд» на процесс электролиза


МРТ изображения (спектрометр Bruker 400 WB Avance III) электрохимической ячейки, заполненной водным раствором хлорида железа (II), при различных напряжениях.

Glass Phys Chem, 2017, 43, 70–74

V.V. Tomaev, A.S. Mazur, A.S. Grevtsev

“A study of the process of thermal oxidation of lead selenide by the NMR and XRD methods”

Glass Phys. Chem., 2017, 43, 70–74
DOI:10.1134/S1087659617010163

Studies of the process of oxidation of powder samples of lead selenide in a dry air atmosphere have been performed. As shown by the methods of X-ray diffraction and scanning electron microscopy, the process of thermal treatment of samples resulted in the formation of the PbSeO3 phase, aside from the initial PbSe phase. Studies by the method of nuclear magnetic response (NMR) allowed revealing the dynamics of changes in the spectrum under the changed thermal treatment conditions.

 

Eur. J. Mineral., 2016, 28, 931–941

T.L. Panikorovskii, S.V. Krivovichev, E.V. Galuskin, V.V. Shilovskikh, A.S. Mazur, A.V. Bazai

“Si-deficient, OH-substituted, boron-bearing vesuvianite from Sakha-Yakutia, Russia: a combined single-crystal, 1H MAS-NMR and IR spectroscopic study”

Eur. J. Mineral., 2016, 28, 931–941
DOI:10.1127/ejm/2016/0028-2570

источник: http://www.ingentaconnect.com/content/schweiz/ejm/2016/00000028/00000005/art00006

Single crystals of Si-deficient vesuvianite with significant degree of hydrogarnet-type (SiO4)4−–(O4 H4)4− substitution occur as epitactic overgrowth on the surface of large wiluite crystals from the Wiluy River, Sakha–Yakutia, Russia. Electron-microprobe analysis revealed considerable Si-deficiency, Si ranging from 16.30 to 17.50 apfu. The crystal structure of the mineral has been refined in the P4/nnc space group, a = 15.5876(4), b = 11.8021(5) Å to R 1 = 0.028 for 1533 unique observed reflections. The refinement of the site-occupancy factors confirmed significant vacancy at the Z(1) and Z(2) sites (27% and 10%, respectively), with associated increase of the Z(1)–O and Z(2)–O bond lengths to 1.697 and 1.655 Å, respectively. The increased size of the Z(1) tetrahedra results in the compression of the X(1) polyhedra, while the expansion of the Z(2) tetrahedra is compensated by the compression of the X(4) polyhedra. As a result, the significant degree of the hydrogarnet-type substitutions does not have an essential influence upon the unit-cell parameters compared to the usual defect-free vesuvianite. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) curves indicated two steps of the weight loss in the temperature ranges of 600–900°C (2.08 wt%) and 1014°C (2.22 wt%). The total weight loss is estimated as 4.30%, which is in good agreement with the total content of OH estimated as 13.72 apfu. The 1H solid state MAS-NMR demonstrates the presence of a strong additional line at 3.38 ppm compared to the usual vesuvianite, which is explained by the existence of the additional H(3) site. The infrared spectrum in the OH-stretching vibration region shows the additional (B′) absorption band at 3618 cm−1 typical for a hydrogarnet-type substitution.

 

New J. Chem., 2016, 40, 10028-10040

A.V. Artem’ev, E.P. Doronina, M.I. Rakhmanova, A.O. Sutyrina, I.Yu. Bagryanskaya, P.M. Tolstoy, A.L. Gushchin, A.S. Mazur, N.K. Gusarova, B.A. Trofimov

“Luminescent CuI thiocyanate complexes based on tris(2-pyridyl)phosphine and its oxide: from mono-, di- and trinuclear species to coordination polymer”

New J. Chem., 2016, 40, 10028-10040
DOI:10.1039/C6NJ02087A

43_artemev

Tris(2-pyridyl)phosphine oxide reacts with CuSCN to form a variety of luminescent complexes, depending on the specified metal-to-ligand ratio and the solvent used, viz. mononuclear [Cu(N,N′,N′′-Py3P=O)(NCS)], dinuclear (N,N′-Py3P=O)Cu(SCN NCS)Cu[(N,N′-Py3P=O)], their co-crystal (2 : 1, correspondingly) and trinuclear {Cu(NCS)[SCNCu(N,N′,N′′-Py3P=O)]2}. In the solid state, these complexes feature red-orange emission upon UV photoexcitation. The reaction of tris(2-pyridyl)phosphine with CuSCN quantitatively produces an almost insoluble coordination polymer, [Cu(Py3P)NCS]n, which exhibits bright green emission. The synthesized compounds are the first members of the hitherto unknown family of Cu(I) thiocyanate complexes supported by tripodal ligands.

 

Экскурсия

20161128_122333212
Обзорная экскурсия для студентов-бакалавров 4 курса химического факультета. П.М. Толстой провел вводную лекцию для наших посетителей, М.А. Вовк, А.С. Мазур, С.М. Сухаржевский провели демонстрацию ЯМР, ЯКР и ЭПР спектрометров.

Курс спектроскопии ЯМР

20161115_1252572
Сегодня в РЦ МРМИ состоялось завершающее занятие серии лекций о современных методах спектроскопии ядерного магнитного резонанса в органической химии, проведенных для сотрудников компании BIOCAD. В ходе занятия была проведена демонстрация работы на современном оборудовании.

Мышиная охота

В группе синтеза и исследования наночастиц и наноструктурированных материалов, Швец Наталья Андреевна проводит тестирование модифицированных наночастицчастиц магнетита в качестве контраста для МРТ. Микротомографические изображения мышей с применением модифицированных наночастиц магнетита были получены сегодня в рц МРМИ на ЯМР спектрометре Bruker Avance III 400 WB.