Characterization of NiO nanoparticles prepared using gelatin and a low-cost synthesis / Характеристики наночастиц NiO, подготовленных с помощью желатина при простом и недорогом методе обобщения / Karakterizacija NiO nanočestica pripremljenih pomoću želatina tokom postupka 'low-cost' sinteze

Nanocomposite material containing NiO nanoparticles decorated on WO3 nanowires could be used for monitoring levels of H2S gas. The effectiveness of this material is mostly determined by NiO properties. The performed study presents the first stage in the preparation of modified NiO/WO3 nanocomposite material. In this article, NiO nanoparticles are prepared by a simple, low-cost method.The behavior of nano-sized NiO particles is probed by X-ray diffraction, Fourier transform Infrared Spectroscopy, Raman spectroscopy, and hysteretic measurement. / Нанокомпозитные материалы, содержащие наночастицы NiO, нанесенные на нанопровода WO3 можно использовать для мониторинга уровня H2S-газа. Эффективность данного материала в основном определяется свойствами этапа NiO. Проведенное исследование представляет собой первый этап в подготовке модифицированного материала NiO/WO3. В данной статье представлено получение наночастиц NiO простым и недорогим методом обобщения. Поведение наноразмерных частиц NiO исследуется с помощью рентгеновской дифракции, инфракрасной спектроскопии с Фурье-преобразованием, рамановской спектроскопии и гистерезисных измерений. / Nanokompozitni materijal koji sadrži nanočestice NiO nanete na WO3 nanožice može se koristiti za monitoring nivoa H2S gasa. Efikasnost ovog materijala najvećim je delom određena svojstvima NiO faze. Izvedena studija predstavlja prvu fazu u pripremi modifikovanog materijala NiO/WO3. U ovom radu NiO nanočestice su pripremljene jednostavnim 'low-cost' metodom sinteze. Ponašanje nanostrukturnih NiO čestica ispitivano je rentgenskom difrakcijom, infracrvenom spektroskopijom sa Furijeovom transformacijom, ramanskom spektroskopijom i histereznim merenjem

Cross sections and transport properties for Na+ in (DXE) gas

In this work we select most probable reactions of alkali metal ion Na+ with dimethoxyethane (DXE) molecule. Appropriate gas phase enthalpies of formation for the products were used to calculate scattering cross section as a function of kinetic energy with Denpoh-Nanbu theory. Calculated cross sections were compared with existing experimental results obtained by guided ion beam tandem mass spectrometry. Three body association reactions of ions with DXE is studied and compared to experimental results. Calculated cross sections were used to obtain transport parameters for alkali metal ion in DXE gas. [Projekat Ministarstva nauke Republike Srbije, br. ON 171037 i br. III 410011

Composition, structure and potential energy application of nitrogen doped carbon cryogels

Resorcinol–formaldehyde (RF) cryogels were synthesized by sol–gel polycondensation of resorcinol with formaldehyde and freeze-drying was carried out with t-butanol. Carbon cryogel (CC) was obtained by pyrolyzing RF cryogels in an inert atmosphere to 950 °C. Nitrogen doped CCs (CCN) were synthesized by introducing melamine into RF precursor mixture solution to obtain nitrogen concentration 2, 6 and 10 wt.%. Material was characterized by elemental analysis, nitrogen adsorption– desorption measurements, scanning electron microscopy (SEM), Raman spectroscopy, FT-IR Spectroscopy. Cyclic voltammetry (CV) was used to investigate capacitive and electrocatalytic properties. Conductivity measurement was also performed. Elemental analysis results confirmed presence of nitrogen in CCN samples in the range from 0.45 to 1.15 wt.%. Raman spectroscopy of the samples showed increase of D and G peak integrated intensity ratio (ID/IG) with nitrogen doping suggesting that the structural disorder as well as edge plane density increase, but according to similar ID/IG values for CCN samples, their share is not directly related to the amount of incorporated N. Characterization by nitrogen adsorption showed that overall specific surface and maximum mesopores are achieved in CCN sample with medium nitrogen concentration. Results of cyclic voltammetry experiments demonstrated maximum capacitance for CCN sample with smallest N wt.% indicating that narrow pore size distribution and high specific surface area are dominant factors to achieve good capacitive behavior. The relatively low doping level of nitrogen reached in CCN samples may be the reason for the incomplete reduction of oxygen to hydroxide and furthermore it turned out that presence of N in the structure of CC had a negligible effect on the otherwise relatively high conductivity of CC. © 2019 Elsevier B.V

Composition, structure and potential energy application of nitrogen doped carbon cryogels

Resorcinol–formaldehyde (RF) cryogels were synthesized by sol–gel polycondensation of resorcinol with formaldehyde and freeze-drying was carried out with t-butanol. Carbon cryogel (CC) was obtained by pyrolyzing RF cryogels in an inert atmosphere to 950 °C. Nitrogen doped CCs (CCN) were synthesized by introducing melamine into RF precursor mixture solution to obtain nitrogen concentration 2, 6 and 10 wt.%. Material was characterized by elemental analysis, nitrogen adsorption– desorption measurements, scanning electron microscopy (SEM), Raman spectroscopy, FT-IR Spectroscopy. Cyclic voltammetry (CV) was used to investigate capacitive and electrocatalytic properties. Conductivity measurement was also performed. Elemental analysis results confirmed presence of nitrogen in CCN samples in the range from 0.45 to 1.15 wt.%. Raman spectroscopy of the samples showed increase of D and G peak integrated intensity ratio (ID/IG) with nitrogen doping suggesting that the structural disorder as well as edge plane density increase, but according to similar ID/IG values for CCN samples, their share is not directly related to the amount of incorporated N. Characterization by nitrogen adsorption showed that overall specific surface and maximum mesopores are achieved in CCN sample with medium nitrogen concentration. Results of cyclic voltammetry experiments demonstrated maximum capacitance for CCN sample with smallest N wt.% indicating that narrow pore size distribution and high specific surface area are dominant factors to achieve good capacitive behavior. The relatively low doping level of nitrogen reached in CCN samples may be the reason for the incomplete reduction of oxygen to hydroxide and furthermore it turned out that presence of N in the structure of CC had a negligible effect on the otherwise relatively high conductivity of CC. © 2019 Elsevier B.V

Determination of magneto-optical quality and refractive index of bismuth germanium oxide single crystals grown by Czochralski technique

Bi12GeO20 single crystals were grown by the Czochralski technique. The critical diameter and the critical rate of rotation were calculated. Suitable polishing and etching solutions were determined. As a result of our experiments, the pale yellow and black single crystals were produced. The structure of the Bi12GeO20 has been investigated by X-ray diffraction, Raman and IR spectroscopy. The atomic ratio Bi/Ge was determined for the both crystals. The refractive indexes of both Bi12GeO20 crystals were determined by the spectroscopic ellipsometry method. Important properties of Bi12GeO20 for sensing applications, optical activity, Faraday rotation and absorption were measured and magneto optical quality was calculated and compared. (c) 2012 Elsevier B.V. All rights reserved