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An Experimental Assesment of Changes to the Size Distribution of Ammonium Nitrate Under Isothermal Conditioning
Talbot, Nicholas ; Ondráček, Jakub ; Ždímal, Vladimír
Results show that for 50nm ammonium nitrate particles, 70-80% losses were recorded through the evaporation chamber. The least volatile was found to be 200nm particulate at 15°C. Generally, at 25°C the greatest reactions were found as was expected from prior research, however an overall increase in particulate concentration at 100nm for all temperature regimes was surprising. Possible multiple physiochemical transformations during transportation through the evaporator, along with activation of impurities within the water could explain these particle gains. The lack of humidity data, inter- transportation temperature profiling and lateral gas measurements limit the effectiveness of this study.
Plný tet: SKMBT_C22013101814592 -  PDF
Plný text: content.csg - PDF
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Basamatikum - Combined Wide Size Range Aerosol Spectromeeter
Ondráček, Jakub ; Mašková, Ludmila ; Smolík, Jiří
Combined wide size range aerosol spectrometer Basamatikum allows to measure particle number size distribution in a range between 20 nm – 20 μm. The instrument separates the measured aerosol particles into 58 size bins. The instrument can automatically switch the scanning between two sampling points (e.g. indoors and outdoors). It consists basically from two aerosol spectrometers (UFPM and APS), electrically actuated ball valve, sampling tubing with isokinetic subsampling to both of the two spectrometers and two sampling lines. The overall control, data logging and saving to file, the switching between sampling lines and the user interface is provided by the means of the LACP-made (Laboratory of Aerosol Chemistry and Physics) software in LabVIEW programming environment.
Plný tet: SKMBT_C22013101814582 - PDF
Plný text: content.csg - PDF
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Kvalita ovzduší v různých typech archivů
Mašková, Ludmila ; Smolík, Jiří ; Ondráček, Jakub
Tento projekt zahrnuje monitoring kvality ovzduší ve vnitřním a vnějším prostředí ve čtyřech vybraných lokalitách. Tyto lokality reprezentuji jednotlivá venkovní prostředí: malá obec, malé město s turistickou sezonou, průmyslová oblast a velké město s dopravním zatížením. Ve všech lokalitách probíhají vždy čtyři intenzivní měřící kampaně v různých ročních obdobích, v průběhu kterých jsou sledovány distribuce početní a hmotnostní koncentrace částic ve vnitřním a vnějším prostředí a jejich chemické složení. Archiv v Třeboni nemá žádným topným ani ventilačním systémem a okna jsou pouze jednoduchá. Depozitáře na Zlaté Koruně a v Teplicích jsou vybaveny topením a dvojitými okny. Archiv Praze je vybaven filtračním systémem s uzavřeným okruhem cirkulace a je snaha o jeho hermetické uzavření vůči okolnímu prostředí. Z tohoto důvodu zde bylo možné sledovat pouze vnitřní koncentrace částic.
Plný tet: SKMBT_C22013101814590 - PDF
Plný text: content.csg - PDF
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Characterization of Filter Materials for Aerosol Research – Size Resolved Penetration
Ondráček, Jakub ; Zíková, Naděžda ; Ždímal, Vladimír
The comparison of penetrations for different types of filtration materials showed wide variety of penetration curves, MPPS and the maximum penetration. This study also confirmed our initial doubts about the standard filter efficiency testing method, regarding the used testing material, setting of MPPS and measuring only the total penetration of polydisperse aerosol. Therefore, such a study could serve also as a basis for improvements in the filter efficiency standard method, which seems to give insufficient and in some perspectives limited or even misleading information.
Plný tet: SKMBT_C22013091913090 - 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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Ultrafine Particle Concentrations: Importance of Local Sources and New Particle Formation in Two Central European Cities
Wonaschuetz, A. ; Wagner, R. ; Aschauer, I. ; Haindl, R. ; Ludwig, W. ; Zecha, G. ; Ondráček, Jakub ; Vodička, Petr ; Zíková, Naděžda ; Ždímal, Vladimír ; Schwarz, Jaroslav ; Hitzenberger, R.
In this study, the importance of local primary sources and new particle formation as sources of fine and ultrafine particles is investigated for winter and summer in two central European cities. Particular attention is given to the impact of local meteorological characteristics: air mass origins play a large role in the characteristics of the background aerosol and the concentrations of trace gases associated with new particle formation and growth, and precipitation and thus the condensational sink.
Plný tet: SKMBT_C22013091713550 - PDF
Plný text: content.csg - PDF
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Number Concentration and Modal Structure of Indoor/Outdoor Fine Particles in Four European Cities
Lazaridis, M. ; Eleftheriadis, K. ; Ždímal, Vladimír ; Schwarz, Jaroslav ; Wagner, Zdeněk ; Ondráček, Jakub ; Drossinos, Y. ; Glytsos, T. ; Vratolis, S. ; Torseth, K. ; Smolík, Jiří
Indoor/outdoor measurements campaigns were performed in naturally ventilated houses and offices in four European cities to investigate the relationship between indoor and outdoor particle number concentrations and aerosol modal structures. The measurements sites were located in Oslo (Norway), Prague (Czech Republic), Milan (Italy) and Athens (Greece). A number of ordinary indoor activities (cooking, smoking, candle burning, etc.) were performed during the measurements to quantify the contribution of particles emitted from indoor sources and the contribution of outdoor particles to the change of the indoor aerosol size spectra.
Plný tet: SKMBT_C22013091712000 - PDF
Plný text: content.csg - PDF
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Difúzní baterie - staronový nástroj k aerosolové spektrometrii nanočástic
Holubová Šmejkalová, A. ; Ondráček, Jakub ; Zíková, Naděžda ; Ždímal, Vladimír
Cílem provedených experimentů bylo vyvinout nový řídící a vyhodnocovací program pro difúzní baterii DB 3040, který by optimalizoval měření s tímto přístrojem. Program umožňuje větší variabilitu parametrů měření DB a vede k tomu, že zdánlivě zastaralý aerosolový spektrometr se separací částic založenou na jejich Brownově pohybu může dobře posloužit při měření rozdělení velikosti nanočástic. Ve srovnání s dnes nejrozšířenější spektrometrií SMPS založenou na elektrické pohyblivosti částic může jeho nasazení být výhodnější v situacích, kdy je třeba měřit relativně nízké koncentrace částic s módy rozdělení velikosti pod dvacet nanometrů.
Plný tet: SKMBT_C22013010916340 - PDF
Plný text: content.csg - PDF
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Penetration of Commercial Filter Materials in Detailed Study
Ondráček, Jakub ; Zíková, Naděžda ; Ždímal, Vladimír
Testing of various filter materials proved the functionality, good precision and reproducibility of a home-made filter tester. The measurements of penetration for standard commercial filter materials might be useful for many scientists and other users working with these materials. The comparison of penetration for different types of filtration materials showed wide variety of penetration curves, MPPS and the maximum penetration. This study also confirmed our initial doubts about the standard filter efficiency testing method, regarding the used testing material, setting of MPPS and measuring only the total penetration of a polydisperse aerosol. Therefore, such a study could serve also as a basis for improvements in the filter efficiency standard method, which seems to give insufficient and in some perspectives limited or even misleading information.
Plný tet: SKMBT_C22012102615351 - PDF
Plný text: content.csg - PDF
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