Thermal and luminescent properties of M2Zn(VO3) 4 (M = Rb, Cs)

We have developed processes for the synthesis of the Rb 2Zn(VO3)4 and Cs2Zn(VO 3)4 tetrametavanadates. Rb2Zn(VO 3)4 has been prepared by solid-state reaction (350 C) between presynthesized RbVO3 and ZnV2O6 powders, and Cs2Zn(VO3)4 has been prepared by the Pechini method (sol-gel process). Both metavanadates crystallize in monoclinic symmetry (sp. gr. P21/m). Thermochemical characterization results demonstrate that the vanadates undergo complex transformations during heating to 450 C and subsequent cooling. As a result, the materials are in a nonequilibrium state at room temperature and consist of both the parent double metavanadates and their peritectic decomposition products. We believe that the formation of the structure of the M2Zn(VO3)4 compounds from their melts is a kinetically hindered process. These compounds are structurally stable only at temperatures below 369 (Rb2Zn(VO 3)4) or 420 C (Cs2Zn(VO3) 4). We have measured for the first time the diffuse reflectance and photoluminescence excitation spectra of the two tetrametavanadates in their emission range and their photoluminescence spectra at various excitation wavelengths and determined their chromaticity coordinates. Their X-ray luminescence and scintillation decay characteristics have been determined for the first time under pulsed electron beam excitation. The electron excitation dissipation processes in the cesium and rubidium compounds are shown to be similar. We discuss the origin of the emission bands in the mixed vanadates and their potential application areas. © 2013 Pleiades Publishing, Ltd

Sol-gel synthesis and crystal chemical properties of the pigment Zn1.9Cu0.1SiO4

Received: 06.12.2018. Accepted: 21.12.2018. Published: 31.12.2018.The pigment Zn1.9Cu0.1SiO4 was obtained by the method of sol-gel synthesis. The crystallization temperature was set at 776 °C, ΔH ≈ –16.3 kJ / mol. Thermal expansion of the individual Zn2SiO4 and Zn1.9Cu0.1SiO4 solid solutions was studied by in situ high-temperature X-ray diffraction. It is shown that the substitution of Zn2+ → Cu2+ does not lead to significant changes in the lattice parameters; in the range from room temperature to 800 °C the structure expands monotonically when heated. The coefficients of volumetric thermal expansion for Zn2SiO4 and Zn1.9Cu0.1SiO4 are αV = 8.05 · 10–6 and 8.81 · 10–6 1 / K, respectively. The colorimetric coordinates in the RGB system are 71.8 % red, 72.9 % green and 79.6 % blue, which corresponds to the gray-blue pigment.The work was supported by UB RAS (project 18‑10‑3‑32)

Luminescence mechanism and energy transfer in cesium metavanadate CsVO 3

Photoluminescence properties and relaxation dynamics of electronic excitations in cesium vanadate CsVO 3 have been studied upon pulse laser excitation in the wide temperature range of 6.5–300 K. A vibronic structure observed in low-temperature PL spectra is considered and interpreted. Peculiarities of luminescence relaxation dynamics and emission spectra of CsVO 3 along with the appearance of the vibronic structure are explained in terms of strong electron-phonon coupling of excited electronic states and centrosymmetric vibrational modes in [VO 4 ] 3- center. A new approach in an interpretation of luminescence processes in vanadates is demonstrated. © 2019 Elsevier Ltd16.5186.2017/8.9The work was supported by Act 211 Government of the Russian Federation , contract № 02.A03.21.0006 . I.A.W. thanks for financial support Minobrnauki initiative research project № 16.5186.2017/8.9 . Authors thank Dr. Mathijs de Jong (Utrecht University) for his kind assistance in laser experiments and Prof. Boris V. Shulgin for fruitful discussions of this work

NIR PHOTOLUMINESCENCE IN C-MODIFIED TITANIUM DIOXIDE WITH ANATASE-BROOKITE MATRIXE

NIR photoluminescence was found in Ti(O,C)2/C with anatase/brookite matrix synthe-sized by thermolysis of titanium glycolate. Effect of carbon content on the NIR PL was ob-served. NIR PL is associated with radiative recombination at Ti3+ centers, which are formed under reducing condition of synthesis.Работа выполнена в соответствии с государственным заданием ИХТТ УрО РАН (тема AAAA-A19-119031890025-9)

RESEARCH OF HYGIENIC PROPERTIES OF POROUS POLYETHYLENE FILMS WITH CaCO3

The complex of hygienic properties of polymeric polyethylene (PE) films with mineral filler СаСО3 is experimentally investigated

RESEARCH OF STRUCTURE OF POROUS POLYETHYLENE FILMS BASED ON A MINERAL FILLER

In the paper, polymer polyethylene films with a mineral filler CaCO3 were studied by gas dynamic porosimetry

Очень ранний клинический ответ при лечении ингибитором янус-киназ тофацитинибом у больных активным ревматоидным артритом: динамика боли и элементов центральной сенситизации

Janus kinase (JK) inhibitors block the intracellular signaling pathways that are responsible for the synthesis of proinflammatory cytokines and mediators, which in turn cause the activation of pain receptors and central sensitization (CS). It is suggested that JK inhibitors can rapidly eliminate pain and reduce the severity of CS.Objective: to evaluate the effect of the JK inhibitor tofacitinib (TOFA) on the intensity of pain and the signs of CS in patients with active rheumatoid arthritis (RA) at 7 and 28 days after therapy initiation.Patients and methods. A study group consisted of 39 patients (79.5% female) (mean age 50.9±11.1 years) with RA (DAS28 5.8±0.6). Of these, 89.7% were seropositive for rheumatoid factor; 82.0% took methotrexate and 18.0% received leflunomide. All the patients were prescribed TOFA 5 mg twice daily due to the inefficacy or intolerance of biological agents. The investigators estimated pain intensity using a Brief Pain Inventory (BPI), rated the presence of a neuropathic pain component (NPC) with the PainDETECT questionnaire, and assessed the signs of CS with the Central Sensitization Inventory (CSI) during the first 4 weeks after TOFA administration.Results and discussion. The patients initially experienced moderate or severe pain (the mean scores of 5.33±2.51 on the numerical rating scale (NRS) included in BPI); 53.8% had signs of CS (CSI scores of ≥40); 17.9% had signs of a NPC (PainDETECT scores of >18). Already on day 7 after the start of TOFA administration, there was a statistically significant decrease in the mean NRS pain intensity scores to 4.06±2.2 (p=0.01) and by 29.4±17.9%, as shown by the patient's assessment of the analgesic effect of therapy (BPI), as well as the severity of CS, namely a decrease in the mean NRS pain score to 35.9±11.2 (p=0.01). On 28 days, the effect became better: there was a reduction in the level of NRS pain to 2.32±1.57 (p<0.001), in pain according to the patient's assessment of the analgesic effect of therapy to 43.6±29.6%; in the median PainDETECT score to 2.5 [0; 8.7] (p<0.001); and in CSI scores to an average of 26.4±13.9 (p <0.001). No serious adverse reactions were noted.TOFA has a rapid analgesic effect, which allows it to be considered as a chooser for pathogenetic therapy in patients with active RA and severe pain, especially in the presence of CS signs and secondary fibromyalgia. Undoubtedly, large-scale, long-term controlled studies with a wider range of estimated parameters are required to clarify the therapeutic potential of TOFA in this patient category. The limitation of this investigation was its open observer design pattern.Conclusion. The use of the JK inhibitor TOFA can achieve a rapid analgesic effect, inter alia due to its effect on CS and NPC.Ингибиторы янус-киназ (ЯК) блокируют внутриклеточные сигнальные пути, отвечающие за синтез провоспалительных цитокинов и медиаторов, которые, в свою очередь, вызывают активацию болевых рецепторов и развитие центральной сенситизации (ЦС). Предполагается, что ингибиторы ЯК могут быстро устранять боль и уменьшать выраженность ЦС.Цель исследования – оценить влияние ингибитора ЯК тофацитиниба (ТОФА) на выраженность боли и признаки ЦС у больных активным ревматоидным артритом (РА) через 7 и 28 дней после начала терапии.Пациенты и методы. Исследуемую группу составили 39 больных РА (средний возраст 50,9±11,1 года, 79,5% женщин), DAS28 – 5,8±0,6. Из них 89,7% были серопозитивными по ревматоидному фактору, 82,0% получали метотрексат и 18,0% – лефлуномид. Всем пациентам был назначен ТОФА 5 мг 2 раза в день в связи с неэффективностью или непереносимостью генно-инженерных биологических препаратов. Оценивались выраженность боли с помощью опросника BPI (Brief Pain Inventory), наличие невропатического компонента боли (НКБ) с помощью опросника PainDETECT и признаков ЦС с помощью опросника CSI (Central Sensitization Inventory) в первые 4 нед после назначения ТОФА.Результаты и обсуждение. Пациенты исходно испытывали умеренную или выраженную боль (в среднем 5,33±2,51 по числовой рейтинговой шкале – ЧРШ, включенной в BPI), 53,8% имели признаки ЦС (CSI ≥40), 17,9% – признаки НКБ (PainDETECT >18). Уже через 7 дней после начала приема ТОФА отмечалось статистически значимое снижение интенсивности боли в среднем до 4,06±2,2 по ЧРШ (р=0,01) и на 29,4±17,9% по оценке анальгетического эффекта терапии пациентом (BPI), а также выраженности ЦС – уменьшение значения CSI в среднем до 35,9±11,2 (р=0,01). Через 28 дней эффект усилился: наблюдалось снижение уровня боли по ЧРШ до 2,32±1,57 (р<0,001), боли по оценке анальгетического эффекта терапии пациентом до 43,6±29,6%, медианы значения PainDETECT до 2,5 [0; 8,7] (р<0,001), показателя CSI в среднем до 26,4±13,9 (р<0,001). Серьезных неблагоприятных реакций не отмечено. ТОФА обладает быстрым анальгетическим эффектом, что позволяет рассматривать его как средство выбора при проведении патогенетической терапии у больных активным РА с выраженной болью, особенно при наличии признаков ЦС и вторичной фибромиалгии. Несомненно, требуются большие по масштабу длительные контролируемые исследования с более широким кругом оцениваемых параметров для уточнения лечебного потенциала ТОФА у этой категории пациентов. Ограничением настоящего исследования явился его открытый наблюдательный характер.Заключение. Использование ингибитора ЯК ТОФА позволяет достичь быстрого анальгетического эффекта, в том числе за счет влияния на ЦС и НКБ

Studies on Formation and Decomposition of the Layered Cobaltite LixNayCoO2

Lithium-sodium cobaltite LixNayCoO2 (x≈y≈0.5) with ordered layered structure is promising thermoelectric material. Here we report the peculiarities of this phase formation and decomposition processes studied by TG/DTA, XRD, SEM, and TEM methods. Significant weight loss resulting from oxygen liberation and endothermic effect at T≈1000°C are the main features of the LixNayCoO2 formation. Decomposition of the ordered phase is accompanied by exothermic effect at ≈940°C and the weight increase. Electron microscopic study shows that the lithium-sodium cobaltite decomposes into LiCoO2 and γ-Na0.7CoO2. Lattices of the initial phase and formed ones demonstrate mutual orientation