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Spatial variability of precipitation annual cycles
Zíková, Naděžda ; Kalvová, Jaroslava (advisor) ; Pišoft, Petr (referee)
This thesis enquires into the spatial variability of precipitation annual cycles and its representation by regional climate models. Goal is to find suitable metrics that could describe spatial character of the precipitation field and consequently evaluate model results. For complete understanding the issue, there is an introduction to modeling with regional climate models and also parameters of the precipitation in the Czech Republic. The main part of the thesis is an application of different methods of descripiton on the results of the regional climate models (including the Czech model ALADIN) and CRU data. Results of the models are compared to observed data transferred into the regular grid. Each method is applied on the model results and assessed with regard to advantages and disadvantages. The metrics that were found useful are recommended for the further evaluation of the spatial variability of precipitation annual cycles. The ALADIN model seems to be quite successfull, weak points are only modelling of the precipitation in spring and the effect of the continentality and oceanity on the precipitation annual cycles.
Assesment of wet deposition of atmospheric aerosol on the background site in the Czech Republic.
Zíková, Naděžda ; Ždímal, Vladimír
The aim of this work is to describe the influence of wet deposition on submicron fraction of the atmospheric aerosol as it was recorded by ground based measurements on a background site. The influence of rainout is assessed through interaction of atmospheric aerosol with horizontal hydrometeors, while the influence of washout through interaction with vertical hydrometeors.
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Plný tet: SKMBT_C22016110313100 - Download fulltextPDF
Penetration Through CE-Marked Respirators - Cut-Based Versus Manikun-Based Method
Ondráček, Jakub ; Serfozo, N. ; Zíková, Naděžda
This work presents size-resolved penetration testing of 13 commercially available filtering facepieces (FFP1, FFP2 and FFP3 filtering classes) on pieces of filtration material (47 mm in diameter) cut from various FFRs (referred as cut-based). Second objective of this work was to measure the size-resolved penetration of 9 complete FFRs (selected from identical filtering facepieces as in the first case) placed on the manikin (refered as manikin-based). The results obtained by these two methods were compared and the real MPPS of all FFRs obtained by both methods were estimated.
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Plný tet: SKMBT_C22015102910290 - Download fulltextPDF
SMPS Spectra Dependence on Air Masses Origin at Košetice Station
Zíková, Naděžda ; Ždímal, Vladimír
The varibility in atmospheric aerosol (AA) concentrations is considerable even at rural background stations with suppressed direct anthropogenic influence (Zíková & Ždímal, 2013), and strongly depends, among other meteorological parameters, on wind speed and direction. The wind direction, however, gives only limited information on the air masses origin, so the more detailed analysis of air mass trajectories was done to describe the variability of the AA at the Košetice station.
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Plný tet: SKMBT_C22014102013541 - Download fulltextPDF
New Particle Formation Analysis of Atmospheric Aerosol at Košetice Observatory
Zíková, Naděžda ; Ždímal, Vladimír
In this work, we present basic statistical analysis of new particle formation events frequency at the Kosetice observatory; the station represents a typical background concentration of atmospheric aerosol in Central Europe.
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Plný tet: SKMBT_C22014011413160 - Download fulltextPDF
Comparison of Size Distribution of Water Soluble Ions in Aerosols in Prague and Vienna
Schwarz, Jaroslav ; Vodička, Petr ; Zíková, Naděžda ; Hitzenberger, R.
A study of mass size distribution of water soluble ions was carried out in Prague and Vienna in winter and summer. The results were similar with some smaller differences.
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Plný tet: SKMBT_C22014011413080 - Download fulltextPDF
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).
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Plný tet: SKMBT_C22013121012060 - Download fulltextPDF
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 - Download fulltextPDF
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 - Download fulltextPDF
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 - Download fulltextPDF

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