Electrochemical Valorization of Lignocellulosic Biomass Amination of Furfural and 5-Hydroxymethylfurfural
Donkeng Dazie, Joel; Koláčná, Lucie; Urban, Jiří; Lamač, Martin; Ludvík, Jiří
2024 - anglický Furfural (FF) and 5-hydroxymethylfurfural (HMF) isolated from waste lignocellulosic biomass represent renewable sources. The present contribution deals with the transformation of FF and HMF into furfuryl amines which are important precursors namely for pharmaceutical synthesis. First, FF and HMF underwent condensation reactions with various amines which were electrochemically monitored to optimize the process. The resulting Schiff bases were identified by NMR and subsequently electrochemically reduced in basic media. The vicinal diamine (aminopinacol) was the main product besides the expected furfuryl amines. This reaction is a contribution to green synthesis because it was performed electrochemically, in water, and without any metallic catalysts. Klíčová slova: furfural; 5-hydroxymethylfurfural; (di)amines Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Electrochemical Valorization of Lignocellulosic Biomass Amination of Furfural and 5-Hydroxymethylfurfural

Furfural (FF) and 5-hydroxymethylfurfural (HMF) isolated from waste lignocellulosic biomass represent renewable sources. The present contribution deals with the transformation of FF and HMF into ...

Donkeng Dazie, Joel; Koláčná, Lucie; Urban, Jiří; Lamač, Martin; Ludvík, Jiří
Ústav fyzikální chemie J. Heyrovského, 2024

Electrochemical Properties of Newly Synthesized Selaginpulvilins
Dostálová, L.; Sokolová, Romana; Schwarzová-Pecková, K.; Rýček, L.
2024 - anglický The electrochemical properties of newly synthesized selaginpulvilin were investigated by cyclic voltammetry and UV-Vis spectroelectrochemistry. The subject of the study were two\nselaginpulvilins differing in the presence of a hydroxyl group in the media of 0.1 mol L-1 tetrabutylammonium hexafluorophosphate as supporting electrolyte in anhydrous acetonitrile. Both\ncompounds provided an oxidative signal in the positive region until +2.0 V. Klíčová slova: oxidation; cyclic voltammetry; selaginpulvilins Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Electrochemical Properties of Newly Synthesized Selaginpulvilins

The electrochemical properties of newly synthesized selaginpulvilin were investigated by cyclic voltammetry and UV-Vis spectroelectrochemistry. The subject of the study were two\nselaginpulvilins ...

Dostálová, L.; Sokolová, Romana; Schwarzová-Pecková, K.; Rýček, L.
Ústav fyzikální chemie J. Heyrovského, 2024

3D-printed Electrodes with Nearly Ideal Charge Transfer Characteristics
Vaněčková, Eva; Sebechlebská, Táňa; Kolivoška, Viliam
2024 - anglický 3D printing is an outstanding manufacturing tool for prototyping customized designs at reduced time and costs, having found applications in fields such as medicine or the automotive industry. The development of printable electrically conductive composite materials brought a revolution to electrochemistry, with 3D-printed electrodes being intensively studied from the viewpoint of\nanalytical performance and stability. However, it is often reported that 3D-printed electrodes have poor charge transfer characteristics, typically due to limited exposure of the electrically conductive phase at the composite surface to the surrounding solution. In this work, we devise and apply simple electrochemical activation procedures that lead to a significant improvement of charge transfer characteristics of 3D printed electrodes. Klíčová slova: three-dimensional printing; electrochemistry; electrodes Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. 3D-printed Electrodes with Nearly Ideal Charge Transfer Characteristics

3D printing is an outstanding manufacturing tool for prototyping customized designs at reduced time and costs, having found applications in fields such as medicine or the automotive industry. The ...

Vaněčková, Eva; Sebechlebská, Táňa; Kolivoška, Viliam
Ústav fyzikální chemie J. Heyrovského, 2024

Reclaiming childhood joy: an adventure in the world of escape room
2024 - Klíčová slova: úniková místnost; znovu získat dětskou radost Plné texty jsou dostupné v knihovně ZČU. Reclaiming childhood joy: an adventure in the world of escape room

Západočeská univerzita v Plzni, 2024

Numerical study of the steady airflow in the human respiratory system during inhaling and exhaling
Lancmanová, Anna; Bodnár, Tomáš
2024 - anglický This paper presents some of the initial results of the numerical simulations of a steady turbulent flow in human upper airways during inhalation and exhalation. The mathematical model is based on the system of Reynolds-Averaged incompressible Navier-Stokes equations complemented by the SST k − ω turbulence model. The simulations were performed using finite-volume open source solver OpenFOAM on a realistic three-dimensional geometry. The main aim of this particular study is to verify the computational setup with special focus on appropriate choice and implementation of boundary conditions. The prescribed boundary conditions are chosen to mimic the physiological conditions during normal breathing cycle. This study aims to gain an insight into the airflow behavior during the inhalation and exhalation process by comparing the results of two distinct simulations corresponding to two different (opposite) flow rates . The obtained local flow rates and flow fields for both cases are presented and mutually compared. This initial work should serve as a foundation for future more complex simulations that will include the time-dependent and compressible effects. Klíčová slova: human airways; incompressible Navier-Stokes; OpenFOAM Plné texty jsou dostupné v digitálním repozitáři Akademie Věd. Numerical study of the steady airflow in the human respiratory system during inhaling and exhaling

This paper presents some of the initial results of the numerical simulations of a steady turbulent flow in human upper airways during inhalation and exhalation. The mathematical model is based on the ...

Lancmanová, Anna; Bodnár, Tomáš
Matematický ústav, 2024

Měření teploty při technické výchově
2024 - V tomto pokusu budeme zkoumat šíření tepla při vrtání. Vyzkoušíme, jak se zahřívají ostré a tupé vrtáky při vrtání ocelové destičky Klíčová slova: vrtání; teplo; experiment Plné texty jsou dostupné v knihovně ZČU. Měření teploty při technické výchově

V tomto pokusu budeme zkoumat šíření tepla při vrtání. Vyzkoušíme, jak se zahřívají ostré a tupé vrtáky při vrtání ocelové destičky

Západočeská univerzita v Plzni, 2024

Use of ceramic clay in work activity lessons at primary school level 1
2024 - Klíčová slova: pracovní činnosti; keramika; hlína; Člověk a svět práce; práce s drobným materiálem; základní škola Plné texty jsou dostupné v knihovně ZČU. Use of ceramic clay in work activity lessons at primary school level 1

Západočeská univerzita v Plzni, 2024

Programming intelligent wiring at the first level of primary education
2024 - Klíčová slova: inteligentní elektroinstalace; Apple HomeKit; Loxone; Philips Hue; technika; algoritmizace; technická výchova; informatika; programování; první stupeň základní školy Plné texty jsou dostupné v knihovně ZČU. Programming intelligent wiring at the first level of primary education

Západočeská univerzita v Plzni, 2024

Internet addiction in relation to depression among students
2024 - Klíčová slova: závislost na internetu; deprese; studenti Plné texty jsou dostupné v knihovně ZČU. Internet addiction in relation to depression among students

Západočeská univerzita v Plzni, 2024

Reaction Mechanisms of Psychoactive Compounds
Sokolová, Romana; Beneš, Marek; Jiroušková, Eliška; Degano, I.
2024 - anglický The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and spectroelectrochemical properties. Both drugs were examined by means of cyclic voltammetry using diagnostic parameters for particular reaction schemes, UV/Vis, and IR\nspectroelectrochemistry. Since water participates in the redox mechanism of both studied compounds, the reaction mechanism was studied under a controlled amount of water in an\nacetonitrile environment. Klíčová slova: oxidation; reduction; IR spectrochemistry Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Reaction Mechanisms of Psychoactive Compounds

The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and ...

Sokolová, Romana; Beneš, Marek; Jiroušková, Eliška; Degano, I.
Ústav fyzikální chemie J. Heyrovského, 2024