National Repository of Grey Literature 10 records found  Search took 0.00 seconds. 
Development and applications of ambient mass spectrometry techniques
Rejšek, Jan ; Cvačka, Josef (advisor) ; Lemr, Karel (referee) ; Klejdus, Bořivoj (referee)
(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...
Preparation of asymmetrically substituted diphenylacetylenes usable in molecular electronics
Rejšek, Jan ; Jindřich, Jindřich (advisor) ; Veselý, Jan (referee)
Preparation of asymetrically substituted diphenylacetylenes usable in molecular electronics Abstract This bachelor's work deals with synthesis of assymetrically substituted diphenylacetylenes and their transformation into (η4 -cyclobutadiene)-(η5 - cyclopentadienyl)cobalt complexes, which should be used and researched as molecular rotors. Multistep synthesis concerning conversion of primary arylamines into tertiary by N-permethylation, nucleophilic acyl substitution and Sonogashira coupling was prepared asymmetrically substituted diphenylacetylene with, which consequently underwent cycloaddition [2 + 2] with cyclopentadienyldicarbonylcobalt. Creating (η4 -cyclobutadiene)-(η5 -cyclopentadienyl)cobalt complexe was identified by MS. Keywords: diphenylacetylene, Sonogashira coupling, (η4 -cyclobutadiene)- (η5 -cyclopentadienyl)cobalt complex, cycloaddition [2 + 2], molecular rotor
The use of ambient ionization techniques in mass spectrometry
Rejšek, Jan ; Cvačka, Josef (advisor) ; Coufal, Pavel (referee)
Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized.
Development and applications of ambient mass spectrometry techniques
Rejšek, Jan
(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...
Development and applications of ambient mass spectrometry techniques
Rejšek, Jan
(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...
Development and applications of ambient mass spectrometry techniques
Rejšek, Jan ; Cvačka, Josef (advisor) ; Lemr, Karel (referee) ; Klejdus, Bořivoj (referee)
(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...
The use of ambient ionization techniques in mass spectrometry
Rejšek, Jan ; Cvačka, Josef (advisor) ; Coufal, Pavel (referee)
Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized.
Preparation of asymmetrically substituted diphenylacetylenes usable in molecular electronics
Rejšek, Jan ; Veselý, Jan (referee) ; Jindřich, Jindřich (advisor)
Preparation of asymetrically substituted diphenylacetylenes usable in molecular electronics Abstract This bachelor's work deals with synthesis of assymetrically substituted diphenylacetylenes and their transformation into (η4 -cyclobutadiene)-(η5 - cyclopentadienyl)cobalt complexes, which should be used and researched as molecular rotors. Multistep synthesis concerning conversion of primary arylamines into tertiary by N-permethylation, nucleophilic acyl substitution and Sonogashira coupling was prepared asymmetrically substituted diphenylacetylene with, which consequently underwent cycloaddition [2 + 2] with cyclopentadienyldicarbonylcobalt. Creating (η4 -cyclobutadiene)-(η5 -cyclopentadienyl)cobalt complexe was identified by MS. Keywords: diphenylacetylene, Sonogashira coupling, (η4 -cyclobutadiene)- (η5 -cyclopentadienyl)cobalt complex, cycloaddition [2 + 2], molecular rotor
Development and applications of ionization techniques in ambient mass spectrometry
Rejšek, Jan ; Vrkoslav, Vladimír ; Cvačka, Josef
Ambient mass spectrometry is a sharply developing subject area. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) are two types of ionization techniques in the ambient mass spectometry. Herein, they were investigated in two research areas: (1) TLC analysis. (2) Localization of insect defense glands.
Development and applications of ionization techniques in ambient mass spectrometry
Rejšek, Jan ; Vrkoslav, Vladimír ; Cvačka, Josef
Ambient mass spectrometry is a sharply developing subject area. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) are two types of ionization techniques in the ambient mass spectometry. Herein, they were investigated in two research areas: (1) TLC analysis. (2) Localization of insect defense glands.

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