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Generation of TiO2 Nanoparticles for Follow-Up Inhalation Experiments with Laboratory Animals
Moravec, Pavel ; Schwarz, Jaroslav ; Vodička, Petr ; Koštejn, Martin
A method of TiO2 nanoparticle generation appropriate for follow-up long lasting inhalation experiments with laboratory animals was tested. Nanoparticles were synthesized in an externally heated tube reactor using titanium tetraisopropoxide as a precursor. Total 264 hours of particle generation in four experimental campaigns was performed with one batch of precursor without observable decrease of precursor volatility. Particle production was studied in wide range of experimental conditions such as reactor temperature, reactor flow rate and precursor vapor pressure by pyrolysis, using nitrogen as a carrier gas, and also in oxidizing atmosphere (10 vol. % of oxygen in the reaction mixture). Particle characteristics were investigated by scanning/transmission electron microscopy, energy dispersive spectroscopy, inductively coupled plasma optical emission spectrometry, elemental and organic carbon analyzer, X-ray diffraction and X-ray photoelectron spectrometry. As a result, particle production with number concentration high above 1.0 x 10(7) #/cm(3) and with primary particle size well below 50 nm can be easily achieved in most of investigated experimental conditions. Particles are free of elemental carbon, content of organic carbon is less than 10 weight %, detected crystalline phase is typically anatase, Ti is present in bonds Ti-O (TiO2) and total Ti concentration recalculated on TiO2 is approximately 80 mass %.
Plný tet: SKMBT_C22015041615090 -  PDF
Plný text: content.csg - PDF
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Synthesis of Lead and Lead Oxide Nanoparticles for Inhalation Experiments
Moravec, Pavel ; Smolík, Jiří ; Ondráček, Jakub ; Vodička, Petr ; Fajgar, Radek
From the three tested methods of NP's generation the evaporation/condensation of metallic Pb seems to be the most suitable for long lasting inhalation experiments due to its simplicity, unambiguous mechanism of NP′s formation and well defined composition. Nevertheless, NP′s can change their composition, at least on the surface layer, during the time-lag between their formation and inhalation. Thermal decomposition of PbTHD2 can produce sufficiently high concentration of NP′s but there is some uncertainty about their composition due to presence of OC in NP′s. Oxidation of PbTHD2 produces carbon free NP′s, but the number concentration of NP′s is somewhat low.
Plný tet: SKMBT_C22013101814595 - PDF
Plný text: content.csg - PDF
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Generation of Pb/PbOx Nanoparticles for Inhalation Experiments
Moravec, Pavel ; Smolík, Jiří ; Ondráček, Jakub ; Vodička, Petr ; Fajgar, Radek
Health aspects of nanoparticles (NP′s) on living beings are considered to be important. However, the real data of the impact of NP′s inhalation are rather rare. A study of allocation of MnOx nanoparticles in organs of laboratory animals in inhalation chamber was presented by Večeřa and Mikuška (2012). For these experiments a source of continual generation of nanoparticles in duration of days or even weeks and in appropriate concentration is necessary. In this work a study of continual generation of Pb/PbOx nanoparticles in hot wall tube reactor are presented.
Plný tet: SKMBT_C22013091912130 - PDF
Plný text: content.csg - PDF
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