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Železniční cestovatel Eduard Bazika aneb Cestování s manželkou
Hlavačka, Milan
2024 - Czech
Ing. Eduard Bazika (1830–1914) nebyl profesionální poutník, ale poutník z profese. Jako absolvent pražské polytechniky se celý život specializoval na železniční stavitelství a jako inženýr nejdříve státních drah a od roku 1855 až do odchodu na odpočinek v roce 1891 soukromé Společnosti státní dráhy (StEG) celý život procestoval, respektive před výstavbou prochodil svěřené železnice v české a moravské krajině. I po odchodu na penzi pracoval pro Zemský výbor Království českého a jeho Železniční výbor a v této pozici opět pracovně putoval po všech koutech Čech, aby posuzoval rentabilitu budoucích místních drah. Jeho zvláštností bylo, že se vždy snažil skloubit své cestovní povinnosti s rodinným životem, což mělo za následek, že jeho žena a děti putovaly s ním po nejrůznějších štacích a železničních stavbách. Stranou neponechával ani dlouhodobější náročnější soukromé cesty s manželkou na světové výstavy a po historických památkách Itálie (v doprovodu Jiřího Stibrala) či k obhlídce nově dokončených alpských železnicích. Jako představitel sebevědomé české střední třídy, která už disponovala volným časem a finančními prostředky (a samozřejmě režijní jízdenkou) dovedl skloubit cestovatelskou povinnost s cestovatelskou vášní a putování vnímal jako nezbytnou součást aktivního životního stylu moderního člověka. Ing. Eduard Bazika (1830–1914) was not a professional pilgrim, but a pilgrim by profession. As a graduate of the Prague Polytechnic, he specialized in railway construction all his life and as an engineer, first of all for the State railways, and from 1855 until his retirement in 1891, he traveled all his life for the private State Railway Company (StEG), or rather, before construction, he traveled the entrusted railways in the Bohemian and Moravian landscape. Even after retiring, he worked for the Land Committee of the Kingdom of Bohemia and its Railway Committee, and in this position he once again traveled to all corners of Bohemia to assess the profitability of future local railways. A peculiarity of his was that he always tried to combine his traveling duties with his family life, which resulted in his wife and children traveling with him to various estates and railway constructions. He did not leave aside longer, more demanding private trips with his wife to world exhibitions and historical monuments in Italy (accompanied by Jiří Stibral) or to inspect the newly completed Alpine railways. As a representative of the self-confident Czech middle class, who already had free time and financial resources (and, of course, an overhead ticket), he was able to combine the obligation to travel with a passion for travel and perceived traveling as a necessary part of the active lifestyle of a modern person. Keywords: Ing Eduard Bazika; pilgrim by profession; railway Available at various institutes of the ASCR
Železniční cestovatel Eduard Bazika aneb Cestování s manželkou

Ing. Eduard Bazika (1830–1914) nebyl profesionální poutník, ale poutník z profese. Jako absolvent pražské polytechniky se celý život specializoval na železniční stavitelství a jako inženýr nejdříve ...

Hlavačka, Milan
Historický ústav, 2024

Electrochemistry of Acetaminophen
Mikysek, T.; Ludvík, Jiří
2024 - English
The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox properties of acetaminophen were studied by means of cyclic voltammetry, and rotating-disk voltammetry. We found that the protonation/deprotonation of acetaminophen acts as a ratedetermining step, where the stability of phenoxy radical intermediate plays an important role. Keywords: acetaminophen; phenacetine; voltammetry Available on request at various institutes of the ASCR
Electrochemistry of Acetaminophen

The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox ...

Mikysek, T.; Ludvík, Jiří
Ústav fyzikální chemie J. Heyrovského, 2024

A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis
Kelíšková, P.; Matvieiev, O.; Sokolová, Romana; Janíková, L.; Behúl, M.; Šelešovská, R.
2024 - English
This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both voltammetric and flow amperometric methods. These approaches were effectively used to analyze model solutions, pharmaceutical preparations, and serum samples spiked with GFE, producing accurate results comparable to those obtained with HPLC/DAD analysis. The developed methods provide straightforward, sensitive, and selective means for determining GFE in various sample matrices, underscoring the potential of SP/BDDE in electrochemical analysis. Keywords: guaifenesin; screen-printed sensor; boron-doped diamond electrode Available on request at various institutes of the ASCR
A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis

This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both ...

Kelíšková, P.; Matvieiev, O.; Sokolová, Romana; Janíková, L.; Behúl, M.; Šelešovská, R.
Ústav fyzikální chemie J. Heyrovského, 2024

Optimization of Parameters Used in the Application of Elimination Voltammetry with Linear Scan
Navrátil, Tomáš; Trnková, L.; Hrdlička, Vojtěch; Li, X.
2024 - English
Elimination Voltammetry with Linear Scan (EVLS) is a well-established mathematical method that aids in understanding an analyzed electrochemical system. In almost 30 years since its derivation, it has become a “black-box” technique that is applied automatically (in most cases due to its incorporation into a voltammetric software) without thinking about its fundamentals. However, the choice of optimum parameters under which DC voltammetric data (from which elimination curves are calculated) is crucial. This contribution deals with revealing the optimum ratio of applied scan rates and their absolute values (i.e., times of recording) in dependence on the character of the investigated system (diffusion-controlled process, adsorption-controlled process, etc.). Keywords: elimination voltammetry with linear scan; optimization; adsorption Available on request at various institutes of the ASCR
Optimization of Parameters Used in the Application of Elimination Voltammetry with Linear Scan

Elimination Voltammetry with Linear Scan (EVLS) is a well-established mathematical method that aids in understanding an analyzed electrochemical system. In almost 30 years since its derivation, it has ...

Navrátil, Tomáš; Trnková, L.; Hrdlička, Vojtěch; Li, X.
Ústav fyzikální chemie J. Heyrovského, 2024

ENHANCING WELD JOINT INTEGRITY IN S460 HIGH-STRENGTH STEEL PLATES: AN EXPERIMENTAL APPROACH
Al Khazali, Mohammad Sami; Malíková, Lucie; Křivý, V.; Seitl, Stanislav
2024 - English
Exploring S460 steel, this research assesses weld toe microstructure and fatigue. It finds that welding affects \nhardness of welded area and fatigue life. These insights are crucial for structural engineering, optimizing welding \npractices for longevity. \nTests confirm increased weld toe hardness correlates with fatigue resistance. This informs design strategies, \nensuring bridge safety under cyclic loads. The study advances understanding of HSS behaviour, influencing future \nwelding techniques. Keywords: High-strength steel; weld's toe; cruciform joints; S460; fatigue behaviour Available at various institutes of the ASCR
ENHANCING WELD JOINT INTEGRITY IN S460 HIGH-STRENGTH STEEL PLATES: AN EXPERIMENTAL APPROACH

Exploring S460 steel, this research assesses weld toe microstructure and fatigue. It finds that welding affects \nhardness of welded area and fatigue life. These insights are crucial for structural ...

Al Khazali, Mohammad Sami; Malíková, Lucie; Křivý, V.; Seitl, Stanislav
Ústav fyziky materiálů, 2024

Fenotypování jarního ječmene na odolnost vůči suchu
Klem, Karel; Findurová, Hana; Panzarová, K.; Pytela, J.; Trtílek, M.; Holub, Petr
2024 - Czech
Odolnost rostlin/plodin vůči suchu představuje komplex vlastností, které se různě uplatňují v závislosti na typu, závažnosti a načasování sucha. Proto je nutné poměrně komplexní hodnocení morfologické a fyziologické fenotypové reakce na sucho. Tato metodika se zaměřuje na vývoj postupů a vyhodnocení komplexní fenotypové odezvy genotypů jarního ječmene na sucho pomocí neinvazivně měřených parametrů založených na červeno-zeleno-modrém (RGB) zobrazování, termálním infračerveném zobrazování a zobrazovací fluorescence chlorofylu měřených v rámci automatizované fenotypovací platformy. Vývoj metodiky byl založen na experimentu, ve kterém byly sledovány dynamické změny odezvy šesti genotypů ječmene, reprezentujících širokou škálu tolerance k suchu (od genotypu velmi citlivého až po genotyp velmi tolerantní), na kontinuální vysychání až k bodu vadnutí a následné opětovné zavlažení. Byly identifikovány tři kritické termíny v průběhu sucha a opětovného zavlažení, klíčové pro identifikaci odolnosti jarního ječmene vůči suchu: i) dosažení 50% hladiny dostupné půdní vody, ii) dosažení bodu vadnutí, iii) úplná regenerace rostlin po opětovném zavlažení. Jednotlivé sledované parametry založené na zobrazovacích metodách ovšem ukázaly potenciál pro hodnocení citlivosti na sucho v různých termínech od počátku vysychání či regenerace. Korelace s relativní odezvou výnosu se postupně zvyšovala u projekční listové plochy hodnocené ze strany (SPA) a dosáhla maxima v bodě úplné regenerace po opětovném zvlažení. Aktuální kvantový výtěžek fotosystému II (ΦPSII) vykazoval nejvyšší korelaci s relativním výnosem zrna kolem bodu vadnutí. Naproti tomu relativní rozdíl teploty listů vůči teplotě okolního vzduchu (Tdiff) vykazoval vysokou korelaci s výnosovou odezvou na sucho dříve, a to již při dosažení 50% úrovně dostupné vody pro rostliny v půdě. Nejvyšší korelace s relativní výnosovou odezvou byly získány u barevné analýzy RGB v bodě vadnutí a po regeneraci, zejména u relativního podílu khaki, béžového, tmavě zeleného a olivově zeleného odstínu. Vícenásobná regrese s parametry poskytujícími Pearsonův korelační koeficient R > 0,5 mírně zlepšila odhad relativní odezvy výnosu na sucho, ale zajistila především významné zlepšení odhadu absolutního výnosu zrna při stresu suchem, přičemž přesnost odhadu se v obou případech pohybovala okolo 90 %. Tato metodika ukazuje, že použití kombinace fenotypovacích metod charakterizujících různé morfologické a fyziologické znaky umožňuje nejen hodnocení tolerance k suchu (na základě relativní výnosové reakce na sucho), které je klíčové pro výběr genetických zdrojů pro následný šlechtitelský proces, ale také umožňuje testovat výnosovou výkonnost nových genotypů při stresu suchem. Drought tolerance is a complex of traits that vary depending on the type, severity, and timing of drought. Therefore, a relatively comprehensive assessment of the morphological and physiological phenotypic response to drought is necessary. This methodology focuses on the development of procedures and evaluation of the complex phenotypic response of spring barley genotypes to drought using non-invasively measured parameters based on red-green-blue (RGB) imaging, thermal infrared imaging, and chlorophyll fluorescence imaging measured within an automated phenotyping platform. The development of the methodology was based on an experiment in which the dynamic changes in the response of six barley genotypes, representing a wide range of drought tolerance (from a very sensitive to a very tolerant genotype), to continuous drying until the point of wilting and subsequent re-watering were monitored. Three critical time points during drought and re-watering were identified, key for detecting drought tolerance: i) reaching 50% of available soil water, ii) reaching wilting point, iii) full plant recovery after re-watering. However, the different imaging-based parameters monitored showed potential for assessing drought sensitivity at different time points from the onset of drying or recovery. The correlation with relative yield response increased progressively for the side projected leaf area (SPA) and reached a maximum at the point of complete recovery after re-watering. The actual quantum yield of photosystem II (ΦPSII) showed the highest correlation with relative grain yield around the wilting point. In contrast, the relative difference of leaf temperature to ambient air temperature (Tdiff) showed a high correlation with yield response to drought earlier, as early as at the point of reaching 50% of the level of soil water available to plants. The highest correlations with relative yield response were obtained for RGB colour analysis at the wilting point and after recovery, especially for the relative proportion of khaki, beige, dark green, and olive-green hues. Multiple regression with parameters providing a Pearson correlation coefficient R > 0.5 slightly improved the estimation of the relative yield response to drought, but mainly provided a significant improvement in the estimation of absolute grain yield under drought stress, with an estimation accuracy of around 90% in both cases. This methodology shows that the use of a combination of phenotyping methods in characterising different morphological and physiological traits not only allows the assessment of drought tolerance (based on relative yield response to drought), which is crucial for the selection of genetic resources for subsequent breeding, but also allows the testing of the yield performance of new genotypes under drought stress. Keywords: spring barley; drought; drought tolerance; phenotyping; rgb imaging; chlorophyll fluorescence imaging; thermal infrared imaging; yield Available at various institutes of the ASCR
Fenotypování jarního ječmene na odolnost vůči suchu

Odolnost rostlin/plodin vůči suchu představuje komplex vlastností, které se různě uplatňují v závislosti na typu, závažnosti a načasování sucha. Proto je nutné poměrně komplexní hodnocení morfologické ...

Klem, Karel; Findurová, Hana; Panzarová, K.; Pytela, J.; Trtílek, M.; Holub, Petr
Ústav výzkumu globální změny , 2024

PROPERTIES OF NANOCRYSTALLINE FE-NI PARTICLES PREPARED BY THERMAL REDUCTION OF OXALATE PRECURSORS
Švábenská, Eva; Roupcová, Pavla; Havlíček, Lubomír; Schneeweiss, Oldřich
2024 - English
Recent technological advancements require development of cost-effective and high-performance magnets \nwhich ideally do not contain rare earth metals or noble metals. The promising candidates are Fe-Ni-based \nalloys, in particular, the Fe50Ni50 L10 phase (tetrataenite), which has a great perspective for producing hard \nmagnetic materials. Our study explores a promising method for preparing nanoparticles of Fe-Ni alloy from an \niron-nickel oxalate precursor. The coprecipitation method was employed to prepare oxalate precursors, \nfollowed by controlled thermal decomposition in a reducing hydrogen atmosphere. The morphology and \nproperties of the resulting particles were analysed using scanning electron microscopy (SEM) coupled with \nenergy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Mössbauer spectroscopy (MS), and \nmagnetic measurements.\nThe SEM analysis revealed that the particles have approximately cube-shaped unit cell morphology with a\nsize in a range of 1 - 2 μm. Upon annealing, the samples contain multiple phases with varying Fe-Ni content.\nMagnetic measurements confirmed the formation of magnetically suitable Fe-Ni phases in the samples after \nannealing. Mössbauer spectroscopy emerged as a highly effective method for characterizing individual phases \nof the Fe-Ni system. Keywords: Magnetic materials; thermal decomposition; Mössbauer spectroscopy Available at various institutes of the ASCR
PROPERTIES OF NANOCRYSTALLINE FE-NI PARTICLES PREPARED BY THERMAL REDUCTION OF OXALATE PRECURSORS

Recent technological advancements require development of cost-effective and high-performance magnets \nwhich ideally do not contain rare earth metals or noble metals. The promising candidates are ...

Švábenská, Eva; Roupcová, Pavla; Havlíček, Lubomír; Schneeweiss, Oldřich
Ústav fyziky materiálů, 2024

Application of In situ TR Spectroelectrochemical Techniques in Determination of Redox Mechanism of Bioactive Compounds
Sokolová, Romana; Jiroušková, Eliška; Degano, I.; Wantulok, J.; Nycz, J.
2023 - English
The electron transfer reactions play an important role in many natural processes. Reactions such as \ndissociation, protonation, and reactions with water and other small molecules often occur in \nbiotransformation. The reaction schemes involving these chemical reactions coupled to the \nelectron transfer can be determined by cyclic voltammetry. Additionally, in \nsitu spectroelectrochemistry can efficiently contribute to the determination of oxidation or \nreduction mechanism. This technique provides information about the electroactive chromophore during \nthe redox process allowing to identification the first reaction intermediates. The final reaction \nproducts were identified by chromatographic techniques. This study represents a key role of TR \nspectroelectrochemistry in the determination of reaction intermediates in the case of \n1,10- phenanthroline derivative substituted by bioactive phenothiazine unit and \ndrug 3- fluorophenmetrazine (2-(3-fluorophenyl)-3-methylmorpholine, 3-FPM). Co pound 3-FPM\nhave recently appeared as the new psychoactive substance in the drug market.\n Keywords: IR spectroelectrochemistry; psychoactive substances; oxidation mechanism Available on request at various institutes of the ASCR
Application of In situ TR Spectroelectrochemical Techniques in Determination of Redox Mechanism of Bioactive Compounds

The electron transfer reactions play an important role in many natural processes. Reactions such as \ndissociation, protonation, and reactions with water and other small molecules often occur in ...

Sokolová, Romana; Jiroušková, Eliška; Degano, I.; Wantulok, J.; Nycz, J.
Ústav fyzikální chemie J. Heyrovského, 2023

A polarizable reference electrode
Mareček, Vladimír
2023 - English
New concept of a reference electrode for electrochemical systems resolves a problem of a poor \npotential stability of refence electrodes based on the distribution of a strongly \nhydrophobic common cation between two immiscible electrolyte solutions (TTTES). The use of a \npolarizable metal electrode instead of a classical reference electrode is demonstrated in \n a modified conventional four-electrode cell with TTTES. A simple battery operated potentiostat \ncontrols the working electrode potential in a three-electrode configuration. The working metal \nelectrode then serves as a polarizable reference organic solvent electrode in a four-electrode \nsystem for the polarization of the water/organic solvent interface.\n\n Keywords: reference electrode; liquid/liquid interface; chloride extraction Available on request at various institutes of the ASCR
A polarizable reference electrode

New concept of a reference electrode for electrochemical systems resolves a problem of a poor \npotential stability of refence electrodes based on the distribution of a strongly ...

Mareček, Vladimír
Ústav fyzikální chemie J. Heyrovského, 2023

Elektrochemické studium pH závislých redoxních vlastností komplexů mědi s aza-makrocyklickými ligandy
Koláčná, Lucie; Maďar, M.; Kubíček, V.; Ludvík, Jiří
2023 - Czech
Molekulární elektronika je progresivní směr moderní materiálové chemie. Zabývá se vývojem\nelektronických prvků na úrovni jedné molekuly. Nejdůmyslnější molekulární elektroniku\nnajdeme v přírodě v podobě metaloenzymů. Jedním ze směrů výzkumu jejich modelů jsou\nkomplexy různě substituovaných azamakrocyklů. Předností těchto molekul je jejich stabilita a\ndobře definovaná syntéza. Investigated Cu(II) complexes are based on plain or cross-bridged cyclam. The\nelectrochemically inactive cyclam was modified by carboxylate, phosphonate, or phenolate\npendant arms. Cu(II) represents the main redox center of the complexes. Modification of the\nligand causes a changed pattern of complex redox response in buffered aqueous solution.\nIrreversible Cu(II) reduction results in complex decomposition to amalgamated copper and\nligand in excess. After Cu(0) electrochemical in situ re-oxidation, copper and ligand are recomplexed.\nComplexes undergo isomerization, accelerated by increasing the temperature. The\ninfluence of pH on complex isomerization and the reversibility of its reduction was described. Keywords: cyclam; Cu(II) complexes; pendant arms Available on request at various institutes of the ASCR
Elektrochemické studium pH závislých redoxních vlastností komplexů mědi s aza-makrocyklickými ligandy

Molekulární elektronika je progresivní směr moderní materiálové chemie. Zabývá se vývojem\nelektronických prvků na úrovni jedné molekuly. Nejdůmyslnější molekulární elektroniku\nnajdeme v přírodě v ...

Koláčná, Lucie; Maďar, M.; Kubíček, V.; Ludvík, Jiří
Ústav fyzikální chemie J. Heyrovského, 2023

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