Number of found documents: 402
Published from to

Graphite Electrode Modified by Poly(Methylene Blue) and its Electrocatalytic Activity towards Hydrogen Sulfide Oxidation
Zlámalová, Magda; Janda, Pavel; Nesměrák, K.
2017 - English
This research is focused on the electrochemical synthesis and characterization of\npoly(methylene blue) (pMB). Two different carbon-based electrode substrates, basal plane\nhighly oriented pyrolytic graphite (HOPG) and pencil graphite electrode (PGE), have been\nmodified by conductive film of pMB. Electrochemical properties and nanomorphological\nchanges have been investigated by cyclic voltammetry and atomic force microscopy.\nImproved electroactivity of the modified electrodes (PGE/pMB and HOPG/pMB) towards\nsulfhydryl group has been observed and examined modified electrodes were researched for\ntheir possible application in electrochemical sensor for hydrogen sulfide in aqueous solutions. Keywords: Atomic force misroscopy; Cyclic voltammetry; Electropolymerization Available on request at various institutes of the ASCR
Graphite Electrode Modified by Poly(Methylene Blue) and its Electrocatalytic Activity towards Hydrogen Sulfide Oxidation

This research is focused on the electrochemical synthesis and characterization of\npoly(methylene blue) (pMB). Two different carbon-based electrode substrates, basal plane\nhighly oriented pyrolytic ...

Zlámalová, Magda; Janda, Pavel; Nesměrák, K.
Ústav fyzikální chemie J. Heyrovského, 2017

Pilot Experiments With a Micro-Volume Voltammetric Cell for the Determination of Electrochemically Reducible Organic Compounds
Skalová, Štěpánka; Barek, J.; Rodrigues, J. A.; Goncalves, L.M.; Navrátil, Tomáš; Vyskočil, V.
2017 - English
A new micro-volume voltammetric cell for analysis of small volumes\nof electrochemically reducible organic compounds was developed\nand tested. The sample (20-100 mu L) is placed in a narrow glass tube\nwith an agar membrane at the bottom and the working electrode is\nimmersed into the sample. The agar membrane, as anion permeable\nlayer, electrically connects the workin g e lectrode immersed in the\nanalysed sample in the glass tube with a large-volume compartment\n(20 mL) filled with Britton-Robinson buffer, where conventional nonminiaturized\nreference and auxiliary electrodes are placed. The system\nwas tested using a polished silver solid amalgam electrode\n(p-AgSAE) as a working electrode. Sodium anthraquinone-2-sulfonate\nwas used as a model compound because it is intended to use this\nsystem to monitor electrochemically reducible organic compounds. Keywords: agar membrane; micro-volume voltammetric cell; voltammetry Available on request at various institutes of the ASCR
Pilot Experiments With a Micro-Volume Voltammetric Cell for the Determination of Electrochemically Reducible Organic Compounds

A new micro-volume voltammetric cell for analysis of small volumes\nof electrochemically reducible organic compounds was developed\nand tested. The sample (20-100 mu L) is placed in a narrow glass ...

Skalová, Štěpánka; Barek, J.; Rodrigues, J. A.; Goncalves, L.M.; Navrátil, Tomáš; Vyskočil, V.
Ústav fyzikální chemie J. Heyrovského, 2017

Stereoelectrochemistry of Calixarenes
Liška, Alan; Ludvík, Jiří; Vojtíšek, P.
2017 - English
The relationship between the stereochemical properties (shape or molecular geometry in\ngeneral sense) and electrochemical ones (typically number of separate redox proceses, their\nnature and potentials) is very fundamental, however, not easily answerable. The nitro\nsubstituted calix[4]arenes appeared to be suitable series of compounds enabling correlation of\nelectrochemical data (redox potential, current, reversibility) with actual shape, conformation\nand dynamic behavior of the molecules dissolved in solution due to their well defined\ngeometry and clear polarographic and voltammetric response. Electrochemical methods can\nbe therefore used as a straightforward alternative to e.g. temperature dependent NMR\nspectroscopy. The present contribution is focused on thiacalix[4]arenes, their similarities and\ndistinctions from their methylene bridged analogues.\n Keywords: Calixarenes; Thiacalixarenes; Stereoelectrochemistry Available on request at various institutes of the ASCR
Stereoelectrochemistry of Calixarenes

The relationship between the stereochemical properties (shape or molecular geometry in\ngeneral sense) and electrochemical ones (typically number of separate redox proceses, their\nnature and ...

Liška, Alan; Ludvík, Jiří; Vojtíšek, P.
Ústav fyzikální chemie J. Heyrovského, 2017

Single Molecule Conductance and Junction Formation in Solution. Solvent Effect
Lachmanová, Štěpánka; Šebera, Jakub; Gasior, Jindřich; Dupeyre, G.; Lainé, P. P.; Mészáros, G.; Hromadová, Magdaléna
2017 - English
The single molecule conductance of expanded pyridinium derivative terminated by pyridyl\nnitrogen as an anchoring group at both ends of the molecule in two different environments\nwas measured by scanning tunneling microscopy break junction technique (STM-BJ). The\nvalues obtained in commonly used 1,3,5-trimethylbenzene (TMB) significantly differ from\nthe values acquired in a mixture of TMB and ethanol. Markedly lower junction length and\nhigher conductance indicate strong influence of adsorption of the molecule to the substrate\nsurface in pure TMB compared to the TMB and ethanol mixture. Keywords: Single molecule conductance; Expanded pyridinium derivatives; Solvent effect Available at various institutes of the ASCR
Single Molecule Conductance and Junction Formation in Solution. Solvent Effect

The single molecule conductance of expanded pyridinium derivative terminated by pyridyl\nnitrogen as an anchoring group at both ends of the molecule in two different environments\nwas measured by ...

Lachmanová, Štěpánka; Šebera, Jakub; Gasior, Jindřich; Dupeyre, G.; Lainé, P. P.; Mészáros, G.; Hromadová, Magdaléna
Ústav fyzikální chemie J. Heyrovského, 2017

Electrochemical biosensors with flow-through enzymatic reactors
Josypčuk, Oksana; Josypčuk, Bohdan
2017 - English
Twelve enzymatic biosensors with various silica powder reactors were fabricated and tested.\nExperiments with six silica materials showed that mesoporous silica SBA-15 was the best one\nin terms of covering by enzymes, sensitivity and lifetime of biosensors. The current response\nof the SBA15-glucose oxidase (GOx) sensor started to decrease only after 200-day testing.\nThe used amalgam tubular detector in a flow system allowed working at highly negative\npotentials. Statistical results of parallel measurements of model solutions with the fabricated\nbiosensors show their high accuracy and sensitivity. The proposed SBA15-GOx biosensor\nwas used for determination of glucose in commercial honey. Keywords: Biosensor; Amperometry; Enzymatic reactor Available on request at various institutes of the ASCR
Electrochemical biosensors with flow-through enzymatic reactors

Twelve enzymatic biosensors with various silica powder reactors were fabricated and tested.\nExperiments with six silica materials showed that mesoporous silica SBA-15 was the best one\nin terms of ...

Josypčuk, Oksana; Josypčuk, Bohdan
Ústav fyzikální chemie J. Heyrovského, 2017

Voltammetric Determination of Tumor Biomarkers using Flow Injection Analysis with Amperometric Detection
Makrlíková, Anna; Matysik, F.-M.; Barek, J.; Vyskočil, V.
2017 - English
Three tumor biomarkers (homovanillic acid, vanillylmandelic acid,\nand 5-hydroxyindole-3-acetic acid) have been determined by flow\ninjection analysis with amperometric detection at screen-printed\ncarbon electrodes in optimum medium of Britton-Robinson buffer\n(0.04 mol l-1, pH = 2.0). Dependences of the peaks current on the\nconcentration of biomarkers were linear in the tested concentration\nregion from 0.05 to 100 mu mol l-1, with the limits of detection of\n0.065 mu mol l-1 for homovanillic acid, 0.053 mu mol l-1 for vanillylmandelic\nacid, and 0.033 mu mol l-1 for 5-hydroxyindole-3-acetic acid (calculated\nfrom heights), and 0.024 mu mol 1-1 for homovanillic acid,\n0.020 mu mol l-1 forvanillylmandelic acid, and 0.012 mu mol l-1 for 5-hydroxyindole-3-acetic acid (calculated from areas), respectively. Keywords: flow injection analysis; 5-hydroxyindole-3-acetic acid; homovanillic acid Available on request at various institutes of the ASCR
Voltammetric Determination of Tumor Biomarkers using Flow Injection Analysis with Amperometric Detection

Three tumor biomarkers (homovanillic acid, vanillylmandelic acid,\nand 5-hydroxyindole-3-acetic acid) have been determined by flow\ninjection analysis with amperometric detection at ...

Makrlíková, Anna; Matysik, F.-M.; Barek, J.; Vyskočil, V.
Ústav fyzikální chemie J. Heyrovského, 2017

Hollow-fibre Based Microextraction and Voltammetric Determination of Vanillylmandelic Acid
Hrdlička, Vojtěch; Barek, J.; Navrátil, Tomáš
2017 - English
New method of liquid/liquid/liquid hollow fibre based microextraction of vanillylmandelic acid coupled with voltammetric determination is being developed. Selected liquid membranes based on alcohols, aliphatic hydrocarbons and esters were tested. Highest enrichment factor of 2.52 after 30 minutes of extraction was obtained using propyl benzoate, RSD = 18.2 % (n=5). Mechanically and cathodically pretreated (-1000 mV vs. Ag/AgCl/3M KCl, 15 s) boron doped diamond electrode in a miniaturized arrangement was used for DPV determination. LOD = 1.2 micromol/l, RSD = 5.9% (n=10) for a 10 microl extract. Keywords: Hollow-fibres; Liquid phase microextraction; Voltammetry Available at various institutes of the ASCR
Hollow-fibre Based Microextraction and Voltammetric Determination of Vanillylmandelic Acid

New method of liquid/liquid/liquid hollow fibre based microextraction of vanillylmandelic acid coupled with voltammetric determination is being developed. Selected liquid membranes based on alcohols, ...

Hrdlička, Vojtěch; Barek, J.; Navrátil, Tomáš
Ústav fyzikální chemie J. Heyrovského, 2017

Long-Term Sustainability of Research Infrastructures
Hrušák, Jan; Harrison, A.; Lenoir, L.
2017 - English
The second volume of the ESFRI Scripta series is dedicated to\nthe outcomes of the ad hoc Working (WG) Group on Long-Term\nSustainability (LTS) of Research Infrastructures.\nThe LTS WG was created by ESFRI in 2016 to comprehensively respond\nto the Conclusions of the Competitiveness Council of the European\nUnion of 27th May 2016 that „underlines the importance of ensuring\nLong-Term Sustainability of Research Infrastructures and invites the\nCommission to prepare together with ESFRI and relevant stakeholders a\ntargeted action plan“.\nESFRI has previously developed its concept of lifecycle of the Research\nInfrastructures in the framework of the Roadmap evaluation exercise,\nand at all stages of the lifecycle different aspects of sustainability were\nidentified. The LTS WG has analysed the Long-Term Sustainability\nof Research Infrastructures from a broad perspective taking the\nESFRI viewpoint well beyond the mere economical analysis. Scientific\nexcellence is the condition sine qua non for sustainability throughout\nthe entire RI lifecycle, and its persistence is crucial in the long-term\noperational phase. Excellence in science and outstanding quality services\nto the users are imperative for the successful performance of each\nResearch Infrastructure, and they are addressed in the monitoring and\nreviewing processes by ESFRI. Keywords: sustainability; research infrastructures; ESFRI Available in digital repository of the ASCR
Long-Term Sustainability of Research Infrastructures

The second volume of the ESFRI Scripta series is dedicated to\nthe outcomes of the ad hoc Working (WG) Group on Long-Term\nSustainability (LTS) of Research Infrastructures.\nThe LTS WG was created by ...

Hrušák, Jan; Harrison, A.; Lenoir, L.
Ústav fyzikální chemie J. Heyrovského, 2017

High resolution infrared spectroscopy as diagnostic tool for combustion and plasma chemistry
Zelinger, Zdeněk; Nevrlý, Václav; Grigorová, Eva; Bitala, P.; Dostál, Michal; Suchánek, Jan; Kubát, Pavel; Engst, Pavel; Ferus, Martin; Kubelík, Petr; Civiš, Svatopluk
2017 - English
Monitoring of transient species within combustion experiments (laminar flames, shock-tubes, flow reactors, etc.) is still relatively challenging task especially if application of non-invasive, i.e. optical detection methods is required. High resolution infrared spectroscopy is based on observation of the fine rotation structure that accompanies vibration transitions and thus provides direct information essential to characterization of both molecular structure and reaction dynamics. Thanks to its outstanding advantage enabling unambiguous assignment of specific molecular system according to its spectral feature, it can serve as a helpful tool for exploring complex reaction mechanisms as well as chemical reactivity of individual species present in laboratory flames or plasmas.\nPrevious studies gaining new insights into combustion and plasma chemistry as well as our recent advances targeted towards application of high resolution infrared spectroscopy for species concentration measurement in laminar flames are summarized here below. Keywords: spectroscopy; plasma chemistry; infrared spectra Available at various institutes of the ASCR
High resolution infrared spectroscopy as diagnostic tool for combustion and plasma chemistry

Monitoring of transient species within combustion experiments (laminar flames, shock-tubes, flow reactors, etc.) is still relatively challenging task especially if application of non-invasive, i.e. ...

Zelinger, Zdeněk; Nevrlý, Václav; Grigorová, Eva; Bitala, P.; Dostál, Michal; Suchánek, Jan; Kubát, Pavel; Engst, Pavel; Ferus, Martin; Kubelík, Petr; Civiš, Svatopluk
Ústav fyzikální chemie J. Heyrovského, 2017

Determination of 5-hydroxyindole-3-acetic acid using Flow Injection Analysis with Electrochemical Detection
Makrlíková, Anna; Matysik, F.-M.; Navrátil, Tomáš; Barek, J.; Vyskočil, V.
2017 - English
Tumour biomarker, 5-hydroxyindole-3-acetic acid, has been determined at screen-printed carbon electrodes using flow injection analysis with amperometric detection. Britton-Robinson buffer (0.04 mol-l-1 , pH 2.0) was used as an optimum carrier solution.\nDependence of the peak current on the analyte concentration was linear in the whole tested\nconcentration range (from 0.5 to 100 mikromol-l-1) with limits of detection 0.033 mikromol-l-1 \n(calculated from peak heighst) and 0.012 mikromol-l-1 (calculated from peak areas). Keywords: Amperometric detection; Flow injection analysis; 5-Hydroxyindole-3-acetic acid Available on request at various institutes of the ASCR
Determination of 5-hydroxyindole-3-acetic acid using Flow Injection Analysis with Electrochemical Detection

Tumour biomarker, 5-hydroxyindole-3-acetic acid, has been determined at screen-printed carbon electrodes using flow injection analysis with amperometric detection. Britton-Robinson buffer (0.04 ...

Makrlíková, Anna; Matysik, F.-M.; Navrátil, Tomáš; Barek, J.; Vyskočil, V.
Ústav fyzikální chemie J. Heyrovského, 2017

About project

NRGL provides central access to information on grey literature produced in the Czech Republic in the fields of science, research and education. You can find more information about grey literature and NRGL at service web

Send your suggestions and comments to nusl@techlib.cz

Provider

http://www.techlib.cz

Facebook

Other bases