National Repository of Grey Literature 114 records found  beginprevious95 - 104next  jump to record: Search took 0.15 seconds. 
The Identification and the Origin of the Gemstones Adorning the Insignia of the Charles University in Prague , the Faculty of Science
Petrová, Zdeňka ; Hanusová, Irena (referee) ; Goliáš, Viktor (advisor)
The issue of a sceptre for the newly founded Faculty of Science was first discussed on the meeting of Faculty professors on the 25th November 1921, more than a year after the separation of the Faculty of Science from the Faculty of Arts. The commission elected from among the professors proposed a motion that the new Faculty sceptre should resemble the sceptre of the parental Faculty of Arts. Through a mediation of the Ministry of Education and National Enlightment the design of the new sceptre was ordered from the Academy of Arts, Architecture and Design and it was elaborated by prof. Jaroslav Horejc. However, in January 1923, his design was rejected, because it didn't meet the requirements of the professors' conservative approach. When prof. Horejc refused to make a modified copy of the sceptre of the Faculty of Arts, the professors addressed Tengler, the goldsmith who had made the sceptres of other faculties and of the rector in previous years. Alois Tengler was willing to make a modified copy of the sceptre of Faculty of Arts, but he also proposed a new design (with estimated price of 20 000 K), which the professors found more suitable and subsequently this design was adopted. Tengler committed himself to manufacture the sceptre by the 15th November 1924 and to incorporate any additional design...
Raman spectroscopy - creation and application of spectral database
Průchová, Kristýna ; Šmejkal, Petr (referee) ; Němec, Ivan (advisor)
Bachelor thesis deals with creation of user Raman spectra database and mapping of the availability of comercial and freely accesible Raman libraries. To measure the spectra of the user database FT-Raman spectroscopy was used and also was used the possibility to download spectra freely available on the website of the Sigma-Aldrich company. Created database contains the Raman spectra of 160 organic and inorganic substances. The database was then tested on three samples of different types of analgesics-antipyretics. It was the determination of the composition of Anopyrin from Zentiva, Bayer Aspirin and Paralen Plus from Zentiva. The optimal search setup was discussed on the basis of the results.
Preparation of ultra sharp tips for STM TERS applications
Šilhan, Lukáš ; Man, Ondřej (referee) ; Jan, Vít (advisor)
The goal of this bachelor thesis is preparation of Au tips by electrochemical etching. The theoretical part deals with comparison of microscopy techniques for materials surface characterization and Raman spectroscopy. The experimental part is focused on the settings of optimal etching parametres to gain appropriate geometry of fabricated tips. Function of tips is verified by evaluation of data gained by experimental measuring with this tips. Prepared tips are suitable for applications such as STM and TERS.
Design of the carbon atomic source for deposition of graphene in UHV
Čalkovský, Vojtěch ; Bábor, Petr (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with the design of the atomic carbon source for deposition of graphene layers in UHV conditions. In the first part are briefly described the problems of epitaxial growth, the theory of atomic beams and theory of sublimation. The second part is aimed on graphene description, namely on his properties and on the growth of graphene layers, especially by molecular beam epitaxy. The third part contains brief description of detection and analysis methods of carbon atomic beams. In the practical part of this bachelor's thesis the design and the numeric calculations were made in Simion 8.0 and EOD program. Afterwards the atomic carbon source was constructed. In the conclusion are discussed the obtained results.
The modification of the graphene structures by low energy ions (E
Maniš, Jaroslav ; Čermák,, Jan (referee) ; Mach, Jindřich (advisor)
Diploma thesis deals with the influence of low energy ions on graphene structures. Graphene structures were modified by nitrogen and argon ions of energies lower than 100 eV. Modified structures were analysed by Raman spectroscopy and x-ray photoelectron spectroscopy. The influence of the dose of ions on quality of graphene were investigated as well. In addition, this diploma thesis includes the literature search which focuses on modification of graphene by charged particles.
Study of influence of toxical and nutritional elements on cell metabolism using combination of Raman spectroscopy and Laser-Induced breakdown spectroscopy
Mazura, Martin ; Hrdlička, Aleš (referee) ; Prochazka, David (advisor)
In this work on-line discrimination of six bacteria strains by means of the Multivariate discrimination analysis (MVDA) is presented. Principal components analysis (PCA) was selected as most suitable technique. Two analytical methods – Laser-Induced breakdown spectroscopy (LIBS) and Raman spectroscopy were equipped for chemical analysis of bacteria strains. In order to obtain the best possible bacteria strains differentiation, the data from both methods was analyzed in two ways separately and together. The data from both measurements was normalized separately and afterwards combined in one data frame for simultaneous analysis. This data frame contained information from both analytical methods. Moreover an influence of cultivation period for each bacteria strain was studied. It was determined that Raman spectroscopy is able to discriminate two bacteria strains and LIBS even four bacteria strains. Using combination of both methods the complete discrimination was achieved. From information of first principal component it was determined that most valuable information in LIBS data is not included in different elemental composition but rather in influence of matrix effect. Solely the LIBS was utilized for studying the effect of cultivation period. It was possible to observe transformation of four bacteria strains within 24 hours. Based on results of this work it is possible to assume that combination of Raman spectroscopy and LIBS, because of the complementary information, is suitable for fast discrimination of different bacteria species and strains. Moreover it was determined that LIBS is able to observe the transformation caused by cultivation period.
Methods for identification of PHA producing bacteria
Skřivanová, Veronika ; Turková, Kristýna (referee) ; Obruča, Stanislav (advisor)
This diploma thesis deals with testing, optimazing and comparing methods for the identification of bacteria producing polyhydroxyalkanoates. Work included cultivation and microscopy methods, wherein the bacterial cells were stained with lipophilic dyes Nile red and Sudan black. Further, we also used flow cytometry and spectroscopic methods - Raman spectroscopy and infrared spectroscopy with Fourier transformation, and molecular biological methods, which analyzed the presence of a gene encoding PHA synthase (phaC) by polymerase chain reaction (PCR). PCR assay consist of two reactions, the firt on eis based on amplification of phaC gene along with 16S rRNDA gene, which is common for all the bacteria (multiplex PCR). The second reaction is focused on specific amplification of PHA synthase catalyzing biosynthesis of mcl-PHA. In order to overcome false positive results typical for methods analyzing genotype and also to avoid false negative results occuring in fenotype analyzing methods, the best strategy is to combine both aproaches. According to our results, analysis of presence of phaC gene by PCR can be combined with methods capable of determining presence of PHA in bacterial cells. For this purpose, Raman microspectroscopy seems to be very promising tool, since it is able to detect low content of PHA in cells and PHA can not be confused with other lipid metabolites. The results provide an overview of test methods, their advantages and disadvantages and also to compare different criteria according to which it is possible to choose the method of identification in depending on the adjustable requirements.
Utilization of laser spectrometry for investigation of biological samples: combination of Raman spectroscopy and Laser-Induced Breakdown Spectroscopy (LIBS)
Kouřil, Jan ; Novotný, Karel (referee) ; Samek, Ota (advisor)
This diploma thesis deals with two spectroscopic methods - laser induced breakdown spectroscopy and Raman spectroscopy. These methods were used for analysis of alga Trachydiscus minutus, which was cultivated in copper sulfate solutions of various concentrations. First part of this thesis is dedicated to physics and measurements of laser induced breakdown spectroscopy, second part deals with Raman spectroscopy.
The preparation of Grafen by method CVD
Procházka, Pavel ; Kromka,, Alexander (referee) ; Mach, Jindřich (advisor)
This diploma thesis is mainly focused on the fabrication of graphene layers on the copper foil by the Chemical Vapor Deposition (CVD). For this purpose the high-temperature chamber for the production of the graphene was completed and fully automated. The production of the high area graphene on the copper foil was experimentally achieved. The Raman microscopy and X-ray photoelectron spectroscopy measurements proved that the produced graphene is mostly a monolayer. Graphene layer was transferred on non-conductive substrate.
Aplication of SPM in study and modification of ultrathin films Pt, Co and graphene
Lišková, Zuzana ; Červenka,, Jiří (referee) ; Bartošík, Miroslav (advisor)
This diploma thesis deals with the preparation of the very thin films and their investigation by scanning probe microscopy methods. The ultrathin films of Pt on Pt(111) were created by pulsed laser deposition and the ultrathin films of Co on Pt(111) were deposited by thermal evaporation. The coverage of the substrate was much smaller than one monolayer (in order of hundredths of monolayer). The nucleation theory was verified by these experiments using so-called Onset method. Further graphene sheets were prepared on layer of Si/SiO2 by the mechanical exfoliation from the graphite crystal. The fabricated graphene sheets were studied by micro-Raman spectroscopy, microreflectometry, atomic force microscopy and similar techniques. These methods proved the thinnest graphite layers were consisted of two graphene monolayers.

National Repository of Grey Literature : 114 records found   beginprevious95 - 104next  jump to record:
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