National Repository of Grey Literature 16 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Cloud Processing of Atmospheric Aerosol Spectra.
Zíková, Naděžda ; Pokorná, Petra ; Pešice, Petr ; Sedlák, Pavel ; Ždímal, Vladimír
Atmospheric aerosol (AA), and its influence on the cloud formation, lifetime and other properties, remains the most uncertain (with low confidence level) element in the IPCC radiative forcing estimations (Stocker et al., 2013). The AA, however, is influenced by the cloud processing as well (Collett et al., 2008., Zíková and Ždímal, 2016). Cloud processing of AA (and vice versa) can be described on fogs, or on low clouds present at a suitable station. An example of such a station is Milešovka, where fog is present for almost 55 % of the time (Fišák et al., 2009), giving a great opportunity to explore the changes in the particle size distributions due to the cloud processing.
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Air Pollution Origin Based on One-year PM2.5 and PM10 Measurement at Two Suburban Sites in Prague.
Pokorná, Petra ; Schwarz, Jaroslav ; Rychlík, Š. ; Škáchová, H. ; Smolík, Jiří ; Ždímal, Vladimír ; Vlček, O. ; Hůnová, I.
The objective of this study was to determine air pollution origin in Prague based on the chemical composition of 24h atmospheric aerosol (AA) samples collected in parallel for one-year at two suburban sites. Chemical analysis of PM2.5 and PM10 for elements by ICP-MS, for elemental and organic carbon by thermo-optical method and water-soluble inorganic ions by IC was performed. The AA in Prague air shed was well mixed and nine common PM10 sources of local, urban, regional and long range transport (LRT) origin were apportioned.
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Corporate Culture and its Changes
POKORNÁ, Petra
The aim of this diploma thesis is to analyze corporate culture in a selected organization with a proposal for a change in corporate culture leading to the desired state of cultural dimensions of the knowledge economy. This thesis is divided into two main parts - theoretical and practical. The first part consists of a literary research, which was developed on the basis of the literature related to this issue, including corporate culture and related concepts. In the second part, an analysis of the given issue was carried out. Required information was obtained using the VSM 94 & 2013 questionnaire by Geert Hofstede and the TBSD test. For better quality research, unstructured interviews with the staff took place, as well as an observation, which contributed to the understanding of the organization's entire structure. In the end, changes were proposed in order to improve the situation in the organization and shift it further toward the desired knowledge economy.
Comparison of PM2.5 Chemical Composition and Sources at a Rural Background Site.
Pokorná, Petra ; Schwarz, Jaroslav ; Krejčí, R. ; Swietlicki, E. ; Havránek, Vladimír ; Ždímal, Vladimír
The objective of this study is to compare the PM2.5 chemical composition and sources at a rural background site in Central Europe between the years 1993/1994/1995 and 2009/2010. Chemical analysis of PM2.5 for 29/26 elements by PIXE and water-soluble inorganic ions by IC (2009/2010) was performed. The Positive Matrix Factorization (PMF) was applied to the chemical composition of PM2.5 to identify its sources. The results of chemical analysis and source apportionment have been compared. The decrease in time of almost all elements concentrations especially the metals regulated by the EU Directive are evident. The median ratios show significant improvement in levels of analysed elements in PM2.5. Slight increase of K levels points to rise in the residential wood combustion. The apportioned sources in the years 1993/94/95 were brown coal combustion, oil combustion, dust – long-range transport, re-suspended dust/soil and black coal combustion. The industrial combustion of brown/black coal and oil of the regional origin dominated. The six factors in the years 2009/2010 were assigned as sulphate, nitrate, residential heating, industry, re-suspended dust, sea salt + dust/soil – LRT. The secondary sulphate from coal combustion and residential biomass burning of the local origin dominated.
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Regional Air Pollution Transport and Its Influence to Pollution Hotspot in th Czech Republic.
Kozáková, Jana ; Vodička, Petr ; Pokorná, Petra ; Ondráčková, Lucie ; Ondráček, Jakub ; Hovorka, J. ; Křůmal, Kamil ; Mikuška, Pavel ; Moravec, Pavel ; Schwarz, Jaroslav
The aim of the study was to find out the local effect and the regional air pollution transport effect on the air quality of the Ostrava Radvanice district, the problematic air pollution hot spot.
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Source apportionment of atmospheric aerosol fraction using by highly time resolved characterisation
Pokorná, Petra
The effective air quality management in the heavy polluted areas has to be based on high-quality monitoring with properly designed monitoring network and targeted measurements, which provided information required to source apportionment. The thesis aim was to apportion sources of atmospheric aerosol based on highly time resolved data of mass concentration of size segregated aerosol, its temporal and spatial variability, elemental composition, OC/EC and size distribution of carcinogenic polyaromatic hydrocarbons. Sampling campaigns went during winter and summer in small settlement Březno by Chomutov, residential area Ostrava - Radvanice a Bartovice and Mladá Boleslav in the years 2008 - 2010, 2012, 2013. We determined mass concentrations of PM10, PM1-10, PM1.15-10 and PM0.15-1.5 and their size fraction ratios. Based on the size ratios, the source apportionment of fine fraction (PM0.15-1.15) with focus on PM0.34-1.15 is crucial. We examined seasonal and spatial variability of PM10, PM.2.5, PM1 and PM1-10. Based on the examination, we obtained representative highly-time resolved data with regards to season and sampling locality. We analysed dynamic of size distribution of particle-bond eight carcinogenic polycyclic hydrocarbons. Based on the results the source apportionment of PM0.34-1.15 is crucial....
Source apportionment of atmospheric aerosol fraction using by highly time resolved characterisation
Pokorná, Petra ; Hovorka, Jan (advisor) ; Havránek, Vladimír (referee) ; Schwarz, Jaroslav (referee)
The effective air quality management in the heavy polluted areas has to be based on high-quality monitoring with properly designed monitoring network and targeted measurements, which provided information required to source apportionment. The thesis aim was to apportion sources of atmospheric aerosol based on highly time resolved data of mass concentration of size segregated aerosol, its temporal and spatial variability, elemental composition, OC/EC and size distribution of carcinogenic polyaromatic hydrocarbons. Sampling campaigns went during winter and summer in small settlement Březno by Chomutov, residential area Ostrava - Radvanice a Bartovice and Mladá Boleslav in the years 2008 - 2010, 2012, 2013. We determined mass concentrations of PM10, PM1-10, PM1.15-10 and PM0.15-1.5 and their size fraction ratios. Based on the size ratios, the source apportionment of fine fraction (PM0.15-1.15) with focus on PM0.34-1.15 is crucial. We examined seasonal and spatial variability of PM10, PM.2.5, PM1 and PM1-10. Based on the examination, we obtained representative highly-time resolved data with regards to season and sampling locality. We analysed dynamic of size distribution of particle-bond eight carcinogenic polycyclic hydrocarbons. Based on the results the source apportionment of PM0.34-1.15 is crucial....
In vitro effect of flavonoids on activity of selected biotransformation enzymes in intestinal cell lines
Pokorná, Petra ; Szotáková, Barbora (advisor) ; Matoušková, Petra (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Petra Pokorná Supervisor: Doc. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: In vitro effect of flavonoids on activity of selected biotransformation enzymes in intestinal cell lines Anthocyanins belong to a class of flavonoids which are part of major natural pigments in plants. They are considered to be very beneficial for the human organism. Anthocyanins are widely consumed as fruits, vegetables and red wine and they represent significant constituents of dietary supplements. The popularity of dietary supplements with high concentrations of flavonoids is still increasing, but in addition to positive effects on human health it can also have side effects influence drug metabolizing enzymes and thus affect either desirable or undesirable effects of many drugs. In this thesis in vitro effect of some anthocyanidins (cyanidin, delphinidin, malvidin, pelargonidin) on the proliferation of the intestinal cell line Caco-2 was investigated using the assay of metabolic activity (MTT) and determination of the integrity of the cytoplasmic membrane of cells (neutral red). Then was studied their effect on the activity of selected biotransformation enzymes: glutathione S-transferase (GST),...
Source Apportionment of Atmospheric Aersol Using by Highly Time Resolved Characterization.
Pokorná, Petra ; Hovorka, J. ; Klán, M. ; Křůmal, Kamil ; Mikuška, Pavel ; Hopke, P.K. ; Ždímal, Vladimír
The effective air quality management in the heavy polluted areas has to be based on high-quality monitoring with properly designed monitoring network and targeted measurements, which provided information required to source apportionment. The study aim was to apportion sources of atmospheric aerosol based on highly time resolved data of mass concentration of size segregated aerosol, its spatial variability, elemental composition and OC/EC at three localities in the Czech Republic in the years 2008 – 2010, 2012, 2013. According to the size fractions ratio arose the importance of PM1 source apportionment because of PM0.15-1.15 mean ratio to PM10, which comprised 85 % at the monitoring localities primarily in winter. The main sources of coarse fraction in winter were coal and biomass combustion in Březno by Chomutuv a Mladá Boleslav and road dust re-suspension in Ostrava-Ravanice and Bartovice. In summer dominated soil re-suspension and primary biological – bioaerosol in Březno by Chomutuv. The dominated source of fine fraction was in winter coal combustion Ostrava-Ravanice and Bartovice and biomass burning in Mladá Boleslav. From the above mentioned results arose, that the highly time resolved data are suitable for source identification of size segregated atmospheric aerosol and enable to evaluate representativeness of monitoring station location and measurement campaign.
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National Repository of Grey Literature : 16 records found   1 - 10next  jump to record:
See also: similar author names
14 POKORNÁ, Petra
1 Pokorná, P.
7 Pokorná, Pavla
7 Pokorná, Pavlína
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