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New pathways to plasmonic nanoparticle assembling into 2D and 3D hybrid active systems for SERS of graphene and SERS, SERRS and GERS + SERS of aromatic molecules
Gajdošová, Veronika ; Vlčková, Blanka (advisor) ; Němec, Ivan (referee) ; Michl, Martin (referee)
In the first part of the Thesis, a new type of active system for SERS and SERRS of hydrophobic molecules, namely a 3-dimensional (3D) nanosponge aggregate with incorporated hydrophobic molecules has been developed, and tested by fullerene C60 and hydrophobic free- base tetraphenylporfine (H2TPP). The SERS and SERRS (surface enhanced /resonance/ Raman scattering) limits of detection (LODs) of C60 at four excitation wavelengths spanning the visible spectral region were found to be by one order of magnitude lower than in the reference system, which mimics the previously reported ways of utilization of Ag nanosponges as substrates for SERS and SERRS. The superiority of the newly developed sample is attributed to the efficient localization of the hydrophobic molecules into hot spots in 2D fractal aggregates of Ag nanoparticles (NPs). Diprotonation of H2TPP during the procedure using HCl as the preaggregation agent has been eliminated by employment of NaCl. On the other hand, investigation of the mechanism of H2TPP protonation during the former preparation procedure opened a possibility to employ Ag nanosponge aggregate as nanoreactor. In the second part of the Thesis, 2D assemblies of AgNPs were found to be better substrates for SERS of single layer graphene (SLG) than the 3D ones. In particular, the 2D...
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Excitation wavelength-dependent Raman spectra of single-layer graphene-phtalocyanine hybrid systems
Uhlířová, Tereza ; Vlčková, Blanka (advisor) ; Němec, Ivan (referee)
A systematic chemical and spectroscopic approach to evaluation of the effect of single-layer graphene (SLG) on Raman spectra of free-base phthalocyanine (H2Pc) in glass/SLG/H2Pc hybrid systems has been developed. By a combi- nation of electronic absorption spectra, Raman spectra at five excitation wave- lengths (532, 633, 647, 785 and 830 nm) and excitation profiles of H2Pc Raman spectral bands, the constitution of the three prepared hybrid sysems has been es- tablished in the following manner: Hybrid system I comprises probably a bilayer of H2Pc molecules, system VI approximately a monolayer of H2Pc, and system X a slightly reorganized monolayer of H2Pc molecules. Micro-Raman spectral map- ping of all three hybrid systems yielded H2Pc spectral bands (together with the SLG spectral bands) at all five excitation wavelengths. By contrast, for all three HOPG/H2Pc reference systems (HOPG = highly oriented pyrolytic graphite), prepared by the same procedure as the corresponding samples, H2Pc signal was detected only at 633 and 647 nm excitations. A selective increase of normalized Raman intensities of H2Pc spectral bands for the glass/SLG/H2Pc monolayer hybrid systems at 830 nm was revealed on the basis of a mutual comparison of Raman excitation profiles of all three samples of glass/SLG/H2Pc hybrid systems....
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Fairy-tale in the work of Václav Tille - Říha
Vlčková, Barbora ; Šmahelová, Hana (advisor) ; Merhaut, Luboš (referee)
Fairy-tale in the works of Václav Tille-Říha thesis is based on an analysis and an interpretation of Tille's fairy-tale writings and symbolist stories considering the means of developing symbolist poetics on an outline of a folklore fairy-tale. The target of this thesis is to grasp the function of fairy-tale features in Václav Tille's works which emerged from the intersection of literary adaptation of traditional folklore subjects with symbolist creation. The opening chapter deals with the historical context of Tille's works and its folklorist and literary aspects. The work aim, through the works of Václav Tille, to express a wider framework within the context of symbolist writing and Art Noveau fine arts.
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A stylistic comparison of two modern translations of biblical text from the viewpoint of reception by present-day readers
Vlčková, Barbora ; Dušková, Libuše (advisor) ; Popelíková, Jiřina (referee)
The present thesis deals with two present-day English translations of the Bible - New American Standard Bible, which represents a conservative biblical translation, and Good News Bible, a more liberal translation, written in a way to be readable and accessible to the modern reader. The aim of the thesis is to analyze the two translations in terms of style, focusing on the syntactic and lexical levels. The research is based on a sample of 100 corresponding biblical verses drawn from each of the translations (altogether 200 verses), representing five different narrative parts of the Bible. The analysis of the lexical level is a qualitative one, comparing the nature of the vocabulary used in the two translations; the syntactic level is examined both qualitatively and quantitatively. The thesis attempts not only to describe the findings but also account for them, where possible, in terms of reader reception.
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Optimization of new active surfaces based on plasmonic nanoparticle assemblies for SERS, SERRS and surface-modified luminescence studies of selected molecules
Sutrová, Veronika ; Vlčková, Blanka (advisor) ; Procházka, Marek (referee)
Two types of 3-dimensional (3D) Ag nanosponge aggregates were prepared and tested as samples for surface-enhanced Raman scattering (SERS) and as active surfaces for surface- enhanced luminescence. 3D Ag nanosponge aggregates were assembled from 2D fused fractal aggregates (D = 1.87 ± 0.02) prepared by modification of Ag nanoparticle (NP) hydrosol resulting from the reduction of AgNO3 by NH2OH·HCl. For SERS measurements, 3D Ag nanosponge aggregates with incorporated [Ru(bpy)3]2+ cations and chloride anions were prepared and overlayed by a thin layer of aqueous phase. For SEL measurements, the 3D Ag nanosponge aggregates were assembled from fused fractal aggregates of chloride- modified Ag NPs. After preparation the active surface was overlayed by a 1×10-5 M aqueous solution of [Ru(bpy)3]2+ . The SERRS (1×10-15 M) and SER(R)S (1×10-14 M) limits of detection of [Ru(bpy)3]2+ determined at 445 and 532 nm excitations, respectively, correspond to the single molecule level of the complex detection. Its achievement is attributed to a large electromagnetic mechanism enhancement experienced by [Ru(bpy)3]2+ incorporated in "hot spots", an efficient localization of "hot spots" in the 3D aggregate to the focus of the laser beam in micro-Raman spectral measurements and to a molecular resonance contribution to the...
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Development and testing of new types of active surfaces for investigation of surface-modified optical processes of biologically important molecules
Sutrová, Veronika ; Vlčková, Blanka (advisor) ; Procházka, Marek (referee)
Hydrosols of silver nanoparticles (AgNPs) prepared by reduction of AgNO3 by either NaBH4 (BH-AgNP hydrosol), or NH2OH·HCl (HA-AgNP hydrosol) modified by the addition of HCl were characterized by SPE spectra (SPE = surface plasmon extinction) and transmission electron microscopy, and their SERS (Surface-enhanced Raman Scattering) activity was tested by measuring the SERS or SERRS (Surface-enhanced Resonance Raman Scattering) spectra of 2,2'-bipyridine (bpy) and 5,10,15,20-Tetrakis(1-methyl-4-pyridinio)-21H,23H-porphine (H2TMPyP) testing adsorbates and by determining of their SERS and SERRS spectral detection limits at λexc = 532 nm. For both types of AgNP hydrosols, it was found that the addition of HCl and the addition of testing adsorbate leads to an intergrowth of AgNPs and to the formation of their compact aggregates, in combination with the formation of new Ag(0) adsorption sites. The limit of detection in a macrosampling setup was 1·10-9 M in the system HA-AgNP hydrosol /HCl/bpy and 1·10-5 M in the system BH AgNP hydrosol/HCl/bpy and, in both causes the Ag(0)-bpy surface complex was detected. About one order of magnitude lower detection limit of bpy in the system with HA-AgNP hydrosol is caused by the efficient intergrowth of AgNP in HA-hydrosol resulting into an efficient formation of "hot...
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The subjunctive versus the "should"-construction and the indicative in dependent imperative clauses
Vlčková, Barbora ; Malá, Markéta (advisor) ; Šaldová, Pavlína (referee)
English dependent imperative clauses allow three possible forms of the verb phrase in the predicate: the subjunctive, the should-construction and the indicative. The present study deals with these paradigmatic variants and aims to examine their distribution in British English in a synchronic as well as a diachronic perspective. Drawing on grammars and previous studies, the theoretical part of the thesis provides an overview of the present issue and describes important terms. It is to serve mainly as background for the research part, which follows. The research project consists of two parts: a diachronic and a synchronic one. While the diachronic part focuses on the development of the distribution of the variants in dependent impererative clauses from the second half of the 20th century to the present, the synchronic part attempts to define some factors which may influnce the use of these variants in contemporary English. The study uses various corpora of British English as primary material for the research. Excerpted examples were analyzed and results were produced, on the basis of which conclusions were drawn.
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Fairy-tale motivs in the Czech poetry of the 2nd half of the 19th century
Vlčková, Barbora ; Šmahelová, Hana (advisor) ; Vaněk, Václav (referee)
The bachelor thesis Fairy-tale Motives in Epic of the 2nd half of the 19th Century is based on an analysis of selected texts and their reading, which lead to the enlightening of meaning-creating function of fairy-tale motives in the 2nd half of the 19th Century. The thesis focuses itself on the form of a fairy-tale as a specific narrative form and on a transformation of its function within the context of poetry using fairy-tale features. At the same time, the reference to the tradition of folk fairy-tale is reflected, being represented by the personalities of Karel Jaromír Erben and Božena Němcová. Interpretation of the works is grounded on the study of Vladimír Propp Morfologie pohádky (Morphology of Fairy-tale) which established the structure of fairy-tale functions. The conclusions of this work are based on the comparison of the epic pieces Dědův odkaz (Grandpa's Legacy) by Adolf Heyduk and Vyšehrad by Julius Zeyer with Propp's functional analysis.
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