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Advanced Filter Tester for Size Resolved Penetration Measurements
Ondráček, Jakub ; Zíková, Naděžda ; Ždímal, Vladimír
Aerosol filtration is the most widely used process to capture aerosol particles. It is used in various applications throughout the different areas of interest (emissions cleaning, occupation safety and health, air-conditioning, etc.). In most of these applications, it is useful to have information about penetration, or filtration efficiency, of the chosen filtration material. Information available from filter manufactures, a background of a decision on which filter to use for the specific purposes, is usually not detailed enough. Therefore, new, fully controlled filter testing instrument was developed and thoroughly tested, providing a size-dependent penetration; proving a very good precision and reproducibility of the results. Using this instrument we have measured several commercial filter materials including standard filters (Whatmann, Milipore, Pall) and personal respirators (e.g. 3M).
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22013121012060 - PDF
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Markers of Oxidative Stress are Elevated in Workers Exposed to Nanoparticles
Pelclová, D. ; Ždímal, Vladimír ; Fenclová, Z. ; Vlčková, Š. ; Schwarz, Jaroslav ; Pušman, Jan ; Zíková, Naděžda ; Syslová, K. ; Kuzma, Marek ; Navrátil, Tomáš ; Zakharov, S. ; Kačer, P.
Health-effects of nanoparticles in humans are little understood. Pre-shift and post-shift spirometry, markers in exhaled breath condensate (EBC), and fractional exhaled nitric oxide (FeNO) were measured both in 20 workers exposed to TiO2 aerosol and 19 controls. Particle number size distributions were monitored by aerosol spectrometers SMPS and APS, covering the overall size range 15 nm-10 μm. Simultaneously, the spatial distributions of total particle number and mass concentrations were determined using a particle number concentration monitor (P-TRAK) and a monitor of particle mass concentrations (DustTRAK DRX). Total aerosol concentrations in the production plant varied greatly in both space and time; number concentrations 1x104-2x105 particles/cm3 and mass concentrations 0.1-30 mg/m3. In the workshops, 90% of the particles were smaller than 100 nm in diameter and particle concentrations were 10x higher than in the control room.
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Plný tet: SKMBT_C22013111914100 - PDF
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Fog and Cloud Processingof SMPS Spectra
Zíková, Naděžda ; Ždímal, Vladimír
Atmospheric aerosols have been studied extensively due to the confirmed influence of aerosols on global climate, aerosol – clouds interactions, atmospheric visibility, human health etc. (Kerminen et al., 2005; IPCC, 2007; Wichmann et al., 2000). However, the uncertainties connected to the effects of aerosols on phenomena in the atmosphere are considerable – there are various sources of aerosol particles, having different chemical compositions and particle size distributions (PSD). Moreover, the atmospheric aerosol is exposed to both dry and wet deposition, which further inflences the PSD. In this work, we have focused on cloud and fog processing of aerosol PSD.
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Plný tet: SKMBT_C22013101814583 - PDF
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Mass Size Distribution of Atmospheric Aerosols and Water Soluble Ions atMlada Boleslav in Winter
Schwarz, Jaroslav ; Zíková, Naděžda ; Vodička, Petr ; Hovorka, J. ; Moravec, Pavel ; Ždímal, Vladimír
The importance of the knowledge of aerosol mass size distribution for understanding aerosol behavior is well known for at least few decades. The water soluble ions represent a driving factor controlling hygroscopicity of aerosol particles that determines how the ambient relative humidity influences aerosol particle size. Therefore, hygroscopicity is a substantial parameter in phenomena like particle deposition in the human respiratory tract, particle – cloud interactions, aerosol optical effects etc. For these reasons, the mass size distribution of atmospheric aerosols and water soluble ions was studied at a Czech medium-size-town Mladá Boleslav in winter.
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Plný tet: SKMBT_C22013101815000 - 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.
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Plný tet: SKMBT_C22013091913090 - PDF
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Comparison of Particle Number Size Distributions in Three Central European Capital Cities
Zíková, Naděžda ; Borsós, T. ; Řimnáčová, Daniela ; Smolík, Jiří ; Wagner, Zdeněk ; Weidinger, T. ; Burkart, J. ; Steiner, G. ; Reischl, G. ; Hitzenberger, R. ; Schwarz, Jaroslav ; Salma, I. ; Ždímal, Vladimír
Health aspects of ultrafine aerosol particles in urban environment have been studied extensively in recent years (Salma et al., 2011; Putaud et al., 2010; Qian et al., 2007 etc.). Three main sources of the ultrafine particles have been defined – traffic, biomass burning, and atmospheric nucleation. However, the diurnal changes in intensities of individual sources are of considerable extent, similarly to the scale of variations in particle number concentrations due to meteorological phenomena.
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Plný tet: SKMBT_C22013091814450 - 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.
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Plný tet: SKMBT_C22013091713550 - PDF
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