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Low-energy recycling of poly(ethylen terephthalate) waste
Slabá, Jitka ; Beneš, Hynek (advisor) ; Cajthaml, Tomáš (referee)
This thesis deals with a new low-energy method of chemical recycling of poly(ethylene terephthalate) (PET) using natural oils as reagents and microwave irradiation to accelerate depolymerization. The results of experiments with PET waste and castor oil, when the reaction mixture was heated in microwave reactor, showed that a complete depolymerization of PET chain has occured. Optimal conditions for the depolymerization PET were established: wt. ratio of PET / castor oil = 1 / 9.7, when the molar ratio of ester bonds of PET / hydroxyl groups of castor oil = 1 / 2.7, catalyst : zinc acetate at wt 1% from the PET mass, reaction temperature ranging from 235 to 245řC and the reaction time 60 min. Decomposition experiments also showed, that microwave irradiation accelerated decomposition of PET. Depolymerization reactionin MW reactor was complete at 6x shorter reaction time than the decomposition in the classically heated reactor. The results of analysis showed that the resulting product,the recyclate, was composed of unreacted castor oil and polyol products, that contained partially or fully esterified structural unit of PET, which were ended by ester-linked units of castor oil.
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The Divorce Rate in the Pandemic Year of 2020 in Czechia
Fidranský, Tomáš ; Slabá, Jitka (advisor) ; Kalibová, Květa (referee)
The Divorce rate in the pandemic year of 2020 in Czechia Abstract: The year 2020 was unprecedented in terms of changes in the functioning of both individuals and institutions. This thesis aims to evaluate the impact of anti-epidemic measures implemented to reduce the spread of the Covid-19 pandemic on the divorce rate. It mainly focuses on changes in intensity and structure of divorce rate during the periods of the state of emergency when courts could have been limited in their ability to function properly. Analysis of data from the Czech Statistical Office pointed to a decrease in the total divorce rate in the spring of 2020, at a time of the first pandemic wave. A similar and temporary drop in the divorce rate was already observed in Czechia at the end of the 1990s. The cause behind that decrease was a change in legislature, which made it more difficult for marriages with underage children to get a divorce. Therefore, the decrease in divorce rate intensity occurred only in the group of marriages with underage children. Compared to that, the decrease in 2020 happened almost identically between marriages with underage children present and marriages without underage children present. This divorce rate drop, seen in the spring of 2020, was not sufficiently compensated by the increased divorce rate in the...
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Fertility fluctuations in selected European countries during the COVID-19 pandemic
Švejková, Tereza ; Šťastná, Anna (advisor) ; Slabá, Jitka (referee)
Fertility fluctuations in selected European countries during the COVID-19 pandemic Abstract The aim of this bachelor thesis is to analyze short-term fluctuations in the fertility rate related to the COVID-19 pandemic outbreak in four European countries. The theoretical part introduces the origin of the respiratory disease COVID-19, describes the precautions enforced in order to prevent its uncontrolled spread and its repercussions on people's lives. In terms of demography, intentions and possible changes in female reproductive behavior are closely examined, in regard to the uncertainties of the pandemic era. It contains particular examples from the past when extraneous factors and extraordinary events - including economic crises, health and natural disasters - led to temporary deviations in the level of fertility. The major part of the analysis was conducted based on the data from the Short-Term Fertility Fluctuations database, which is a unique data set of short-term fertility deviation data series. It is a part of the Human Fertility Database, which is referenced in this paper as well. The fertility rates were compared in four selected countries - Italy, Spain, Sweden and Czech Republic based on monthly total fertility rate and a year-on-year change in the number of live births. The results differ in...
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Fertility timing across the Czech women, the 1966-1990 generations
Slabá, Jitka ; Kocourková, Jiřina (advisor) ; Fialová, Ludmila (referee) ; Kuchařová, Věra (referee)
Fertility timing across the Czech women, the 1966-1990 generations Abstract: The mean age of women at the first and second childbirth in Czechia is growing since the beginning of the 90s. The aim of this doctoral thesis is therefore to analyse the intensity and causes of the unplanned postponement of childbirth, mainly from the individual perspective of Czech women. The main sources of data used in the thesis are from the Ženy 2016 survey and the Ženy 2019 survey, that gather data about the women born in Czechia between the years 1966 and 1990. The research contribution of the thesis is twofold. Firstly, the separation of postponement into two phases - planned postponement and unplanned postponement, as both of them contribute to the growing mean age at first childbirth. Secondly, the finding of the sequential nature of fertility timing. First stage of postponement is related to the unfulfillment of defined prerequisites for the first childbirth, such as completion of education, stable position on the labour market or the overall material security. The second stage of the postponement is related to the unsatisfactory partnership situation and the third stage to the health problems. The results show that about one third of Czech women relate themselves to the issue of the unplanned postponement of the first...
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Time use dependent on presence of children in household for generation 40s to 70s of the 20th century in the United States of America
Slabá, Jitka ; Kurtinová, Olga (advisor) ; Šťastná, Anna (referee)
Time use dependent on presence of children in household for generation 40s to 70s of the 20th century in the United States of America Abstract: The fertility of women has declined under reproduction level 2.1 children per women in economic developed countries during the last few decades. At the same time the employment of women has risen and time use has changed. Main aim of this thesis is to understand how generations born in 1940-1979 living in the USA changed the spending of their time. The AHTUS data set is analysed by comparing averages of times spent by total work, paid work, unpaid work and child care. The time spent by total work declined between generations born at 40s and 70s. Average time spent by paid work declined too. The men's average time spent by unpaid work increased and women's average time decreased. In spite of fertility decrease between 40s and 70s generations, the women's and men's time spent by childcare extremely increased. The men's time spent by child care increased five times, while women's time spent by child care increased more than three times. The rise of time spent by child care is realized by increasing in primary and secondary activities. Primary activities contain time spent by childcare, secondary activities include all activities where childcare was declared e as a...
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Fertility timing across the Czech women, the 1966-1990 generations
Slabá, Jitka
Fertility timing across the Czech women, the 1966-1990 generations Abstract: The mean age of women at the first and second childbirth in Czechia is growing since the beginning of the 90s. The aim of this doctoral thesis is therefore to analyse the intensity and causes of the unplanned postponement of childbirth, mainly from the individual perspective of Czech women. The main sources of data used in the thesis are from the Ženy 2016 survey and the Ženy 2019 survey, that gather data about the women born in Czechia between the years 1966 and 1990. The research contribution of the thesis is twofold. Firstly, the separation of postponement into two phases - planned postponement and unplanned postponement, as both of them contribute to the growing mean age at first childbirth. Secondly, the finding of the sequential nature of fertility timing. First stage of postponement is related to the unfulfillment of defined prerequisites for the first childbirth, such as completion of education, stable position on the labour market or the overall material security. The second stage of the postponement is related to the unsatisfactory partnership situation and the third stage to the health problems. The results show that about one third of Czech women relate themselves to the issue of the unplanned postponement of the first...
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Time use dependent on presence of children in household for generation 40s to 70s of the 20th century in the United States of America
Slabá, Jitka ; Kurtinová, Olga (advisor) ; Šťastná, Anna (referee)
Time use dependent on presence of children in household for generation 40s to 70s of the 20th century in the United States of America Abstract: The fertility of women has declined under reproduction level 2.1 children per women in economic developed countries during the last few decades. At the same time the employment of women has risen and time use has changed. Main aim of this thesis is to understand how generations born in 1940-1979 living in the USA changed the spending of their time. The AHTUS data set is analysed by comparing averages of times spent by total work, paid work, unpaid work and child care. The time spent by total work declined between generations born at 40s and 70s. Average time spent by paid work declined too. The men's average time spent by unpaid work increased and women's average time decreased. In spite of fertility decrease between 40s and 70s generations, the women's and men's time spent by childcare extremely increased. The men's time spent by child care increased five times, while women's time spent by child care increased more than three times. The rise of time spent by child care is realized by increasing in primary and secondary activities. Primary activities contain time spent by childcare, secondary activities include all activities where childcare was declared e as a...
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Structures of divorced populations in the Czech Republic and Slovakia according to Census 2011
Slabá, Jitka ; Rychtaříková, Jitka (advisor) ; Kraus, Jaroslav (referee)
Structures of divorced populations in the Czech Republic and Slovakia according to Census 2011 Abstract: This Bachelor Thesis is striving to characterize the population of divorced in the Czech and Slovak Republics on the basis of available data from Census which took place in 2011. The age and sex structure of the divorced is analysed at regional level. Furthermore, potential distinctive features that correlate with the size of population of the divorced on district or regional level are being searched for. The potential correlating characteristics were chosen based on known risk factors of divorce rate, which were published in demographic or sociological literature. According to assumptions the ratio of the divorced on the population is higher in the Czech Republic then in Slovakia. Moreover, the Czech population of the divorced is older compared to the one of Slovakia and the average age of divorced is higher for women than men. In the countries there is a contradictory relationship between the relative size of the population of divorced and the educational level of the population. While in the districts in the Czech Republic with greater ratio of university-educated the relative number of divorced decreases, in Slovakia their number is increasing. In both states it was proven that with increasing number...
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