Adsorption procedure of two cationic surfactants hexadecyltrimethylammonium bromide (HDTMABr) and benzyldimethylhexadecylammonium chloride (BDHDACl) onto two samples of montmorillonite was studied. Infrared spectroscopy and X-ray diffraction proved intercalation of both quaternary cations into the interlayer space of montmorillonite. An aspect of time showed not to be important for the cations adsorption., Zuzana Navrátilová, Petr Wojtowicz, Lenka Vaculíková and Věra Šugárková., and Obsahuje bibliografické odkazy
A combined sorbent was prepared by impregnation of lignite mined in the South Moravian Coalfield, Czech Republic, with chitosan. Sorption performance of the combined sorbent and the untreated lignite was tested for Co(II), Cu(II), and Cd(II) in equilibrium sorption experiments with respect to pH and metal concentration. The amount of metal retained by the sorbent was determined by instrumental neutron activation analysis in the short time irradiation mode with epithermal neutrons. For pH~5, sorption isotherms were determined and fitted using the Langmuir and Freundlich models. The results have been compared with those obtained previously for similar combined sorbent based on naturally oxidized coal mined in the Sokolov Basin, Czech Republic. It has been shown that the effect of chitosan on sorption efficiency of the chitosan-doped coal sorbents strongly depends on solution pH, and type of coal and metal., Martina Havelcová, Jiří Mizera, Vladimír Machovič, Lenka Borecká, Oldřich Přibyl and Ivana Krausová., and Obsahuje bibliografii
Czech botanists have participated in research into the taxonomy, diversity and ecology of plants in the equatorial high Andes since the mid 90s. The results include a description of new species of vascular plants and lichens, a contribution to generic flora, one monography and publication of several dozen original papers. and Petr Sklenář.
The virgin forests of the Krkonoše Mts. have been transformed into less stable spruce monocultures due to economic activities in the past. The objective of the current management of forest ecosystems is to create a compact core area of a sufficient size capable of autoregulation processes. Surrounding areas should be managed in ways that protect and conserve native biodiversity. Conservation efforts should be coordinated between the Czech and Polish sides of the Krkonoše Mts. and Otakar Schwarz.
The extreme gravity of the funeral ceremonies in the Czech Republic is due to the diffusion of the biblical models in all the sections of the population. A definitive shift between the traditional european way of celebrating death of a relative and the Christian tradition seems to have occured at the end of the nineteenth century. If it is true that the majority of Czech funerals end with the cremation of the body (a process originally refused by the Catholic Church), it is also true that the funeral ceremony at the present day fully accomplishes the principle of severity provided by the Bible. Today most of the Czech funeral ceremonies consist mainly in listening to pieces of music recommended by the management of crematories. A less controlled (and probably more natural) expression of mouming seems to be almost extinct in the culture of the Czech majority.