Influence of silver addition on textural properties of new synthetic activated carbon

Starting from macroreticular styrene/divinylbenzene sulfonic acid ion exchange resin the two samples of synthetic activated carbons (SAC), with and without silver, were obtained through carbonization in controlled regime. Detailed sample preparation procedure is described. Characterizations of synthesized samples were conducted using XRD, SEM and N2 physisorption at –196 °C measurements. The influence of applied silver on textural properties of CAS was discussed.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Poly vinyl alcohol PVA with poly ethylene glycol PEG added as a binder for the powder compaction

Poster presented at the Advanced Ceramics and Applications VII Conference, Belgrade, 17-19 September 2018.Conference abstract: [https://hdl.handle.net/21.15107/rcub_dais_4099

Polyvinyl alcohol PVA with poly ethylene Glycol PEG added as a binder for the powder compaction

During the compaction of the powder mixture of ZnO and Mn2O3 (MnCO3) and Fe2O3 compacts were find fragile for further handling. Poly vinyl alcohol PVA was used as a binder in an unusual 20% PVA content. We made as well 2% PVA with 0.6% Poly ethylene glycol PEG and 20% PVA with 6 % PEG. Binder was wrapped over the powder by suspension forming in the polymer water solution and drying afterwards until all water content evaporates. On the these obtained powders employed characterization techniques were: Fourier transformed Infra red FTIR spectra with ATR attenuated total reflection technique as well as differential thermal analysis DTA on the device with low temperature sensitivity and TEM transmition electron microscopy. All binder concentrations gave compacts with good mechanical properties, that can be handled with ease but with adding, a PEG as plasticizer the operating of the anvil and piston were extremely difficult due to friction.Poster: [https://hdl.handle.net/21.15107/rcub_dais_4065

Oxide powder mixture with poly-vinyl alcohol (PVA) and added polyethylene glycol (PEG) as plasticizer

Powder mixture consisted of ZnO, Mn2O3 (MnCO3) and Fe2O3 blended powders, was found laminating during compaction. Polyvinyl alcohol (PVA) and a combination of PVA with polyethylene glycol (PEG) added as a plasticizer, were introduced as polymer binders to improve the compaction of oxide mixtures. It has been done by forming a suspension of oxide mixture and varying the polymer solution concentration and composition. By evaporating the solvent, new materials were obtained, which consist of oxide particles bound via polymer. In such a manner obtained hybrid materials were characterized with attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy, differential thermal analysis (DTA) and transmission electron microscopy (TEM). The oxide polymer material was compacted at 200 MPa and the expansion of this compact during heating was monitored in temperature range up to 550 ºC with dilatometer. It was found that PVA forms graft polymer with PEG and specific interaction with oxide particles surface was revealed

Structural Changes, Dielectric and Ferroelectric Properties of Tribophysically Activated BaTiO3

In order to obtain nanocrystalline material which can be used in MLCC production, the investigations of the influence of BaTiO3 powder tribophysical activation (TPA) on its structural changes, dielectric and ferroelectric properties have been performed. Microstructure development and crystal structure have been studied by mercury porosimetry method, SEM, EDS and X-ray powder diffraction analyses. The modifications of dielectric and ferroelectric properties of sintered samples have been examined and correlated with observed structural changes induced by TPA of starting powders. It has been found that dielectric and ferroelectric properties of tribophysically activated BaTiO3 could be tuned by controlling the grain size and lattice strain of activated nanostructured material

Structural Changes, Dielectric and Ferroelectric Properties of Tribophysically Activated BaTiO3

In order to obtain nanocrystalline material which can be used in MLCC production, the investigations of the influence of BaTiO3 powder tribophysical activation (TPA) on its structural changes, dielectric and ferroelectric properties have been performed. Microstructure development and crystal structure have been studied by mercury porosimetry method, SEM, EDS and X-ray powder diffraction analyses. The modifications of dielectric and ferroelectric properties of sintered samples have been examined and correlated with observed structural changes induced by TPA of starting powders. It has been found that dielectric and ferroelectric properties of tribophysically activated BaTiO3 could be tuned by controlling the grain size and lattice strain of activated nanostructured material

Polyvinyl alcohol PVA with poly ethylene Glycol PEG added as a binder for the powder compaction

During the compaction of the powder mixture of ZnO and Mn2O3 (MnCO3) and Fe2O3 compacts were find fragile for further handling. Poly vinyl alcohol PVA was used as a binder in an unusual 20% PVA content. We made as well 2% PVA with 0.6% Poly ethylene glycol PEG and 20% PVA with 6 % PEG. Binder was wrapped over the powder by suspension forming in the polymer water solution and drying afterwards until all water content evaporates. On the these obtained powders employed characterization techniques were: Fourier transformed Infra red FTIR spectra with ATR attenuated total reflection technique as well as differential thermal analysis DTA on the device with low temperature sensitivity and TEM transmition electron microscopy. All binder concentrations gave compacts with good mechanical properties, that can be handled with ease but with adding, a PEG as plasticizer the operating of the anvil and piston were extremely difficult due to friction.Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/2627

Poly vinyl alcohol PVA with poly ethylene glycol PEG added as a binder for the powder compaction

Poster presented at the Advanced Ceramics and Applications VII Conference, Belgrade, 17-19 September 2018.Conference abstract: [https://cer.ihtm.bg.ac.rs/handle/123456789/2612

Electromagnetic characterization of Ni0.5Zn0.3Co0.2Fe2O4 bulk ceramics in the 1 MHz-12 GHz frequency range

In this paper, NiZnCo ferrite was produced by solid state synthesis, calcination at 1000 °C and sintering at 1250 °C in air atmosphere. The microstructure and phases of the sintered sample were analysed by scanning electron microscopy and X-ray diffraction, respectively. The magnetic properties of the ferrite were evaluated by magnetization and magnetostriction measurements. The complex magnetic permeability and complex permittivity were also measured between 1 MHz-12 GHz and the reflection loss (RL) was calculated in the 100 MHz-12 GHz frequency range. The results show that the ferrite sample presents magnetostrictive behaviour and a saturation magnetization of 71 Am2/kg. Complex permittivity measurements indicate that the material has dielectric behaviour in the whole frequency range studied, with ε′ varying between 7-40, and magnetic behaviour in frequencies between 1 MHz-5 GHz. The minimum RL was found at frequencies between 2.4-3.3 GHz and the calculated RL value for a thickness of 3 mm was lower than −10 dB in frequencies between 2.3-7.3 GHz. These results indicate potential application as microwave absorber in the S band

Structural Changes, Dielectric and Ferroelectric Properties of Tribophysically Activated BaTiO3

In order to obtain nanocrystalline material which can be used in MLCC production, the investigations of the influence of BaTiO3 powder tribophysical activation (TPA) on its structural changes, dielectric and ferroelectric properties have been performed. Microstructure development and crystal structure have been studied by mercury porosimetry method, SEM, EDS and X-ray powder diffraction analyses. The modifications of dielectric and ferroelectric properties of sintered samples have been examined and correlated with observed structural changes induced by TPA of starting powders. It has been found that dielectric and ferroelectric properties of tribophysically activated BaTiO3 could be tuned by controlling the grain size and lattice strain of activated nanostructured material