No (20995)
Number of found documents:
20995
Published from
to
Electrochemical Valorization of Lignocellulosic Biomass Amination of Furfural and 5-Hydroxymethylfurfural
Donkeng Dazie, Joel; Koláčná, Lucie; Urban, Jiří; Lamač, Martin; Ludvík, Jiří
2024 - English
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.
Keywords:
furfural; 5-hydroxymethylfurfural; (di)amines
Available on request at various institutes of the ASCR
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 ...
Electrochemical Properties of Newly Synthesized Selaginpulvilins
Dostálová, L.; Sokolová, Romana; Schwarzová-Pecková, K.; Rýček, L.
2024 - English
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.
Keywords:
oxidation; cyclic voltammetry; selaginpulvilins
Available on request at various institutes of the ASCR
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 ...
3D-printed Electrodes with Nearly Ideal Charge Transfer Characteristics
Vaněčková, Eva; Sebechlebská, Táňa; Kolivoška, Viliam
2024 - English
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.
Keywords:
three-dimensional printing; electrochemistry; electrodes
Available on request at various institutes of the ASCR
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 ...
Palingeneze - obnovení všeho? (Matouš 19,28)
Dus, Jan A
2024 - Czech
V Matoušově verzi Ježíšova zaslíbení (Mt 19,28–30) oproti Markovi a Lukášovi chybí výslovná zmínka o přítomnosti: restituce všeho, co Ježíšovi následovníci opustili, se tak posouvá až do budoucnosti, ve které se chopí vlády spolu se Synem člověka. V zaslíbení figuruje raritní pojem „palingeneze“, jehož bližší časové a věcné určení nelze ze samotného souvětí odvodit. Zatímco v Mt 19,28 je palingeneze podle převažujícího výkladu synonymem pro budoucí obnovu veškerenstva, v Tt 3,5 (jediný další výskyt v NZ) odkazuje totéž slovo na znovuzrození některých lidí, ke kterému došlo v minulosti (při křtu). Ani nebiblická literatura nepřináší jednoznačný precedens – palingeneze bývá zasazována jak do minulosti, tak i do budoucnosti, týká se jak světa, tak i jednotlivců či skupin (Izraele). – Syntax a interpunkce řeckého souvětí ukazují, že oba výklady jsou rovnocenné: palingenezi lze vztáhnout buď (A) k následujícímu výrazu pro „usednutí (Syna člověka na trůn)“, tedy do budoucnosti, anebo (B) k předchozímu výrazu pro „následování (učedníků za Ježíšem)“, tedy do minulosti, kromě toho existuje (C) výklad otevřený. V řeckých, latinských a českých verzích ze 16. století jsou zastoupeny všechny možnosti: Erasmus interpunkčně opravuje Vulgátu (B), Beza nejprve respektuje Vulgátu (A), v anotacích však zvažuje druhé řešení (B), ve čtvrtém a pátém vydání nakonec nechává věc otevřenou (C), v dilematu mezi Vulgátou a Erasmem váhají i dva české překlady z první poloviny 16. stol. (náměšťský 1533, melantrišský 1556/57) (C), většina bratrských překladů počínaje Blahoslavem (1564) se odchyluje od Vulgáty (B), jen kralická Šestidílka (1593/94) váhá (C), v Šestidílce i v kralickém Novém zákoně z r. 1601 Bratří věnují oběma výkladům rovnocennou pozornost v poměrně rozsáhlé poznámce, která je pro svou vyváženost pěkným dokladem intelektuální otevřenosti a tolerance, podobně jako Beza připojují k výkladu (B) nový aspekt: palingeneze může znamenat obnovení celého světa díky evangeliu a prvnímu příchodu Mesiáše. – Vzhledem k dynamickému vývoji v 16. století je překvapivé, že všech deset sledovaných českých překladů z období kolem 20. století se shoduje jen na jedné variantě (A). Zdá se, že variantě (B) hrozí nespravedlivé zapomenutí. Proto si na závěr dovolujeme navrhnout nový, poněkud volnější překlad či parafrázi verše Mt 19,28 v kralickém duchu: „Amen, pravím vám, vy jste šli za mnou, když jsem přišel obnovit svět evangeliem, a až Syn člověka usedne na trůn své slávy, budete to zase vy, kdo usednete na dvanáct trůnů a budete soudit dvanáct kmenů Izraele.“ In Matthew’s version of Jesus’ promise (Matthew 19:28–30), in contrast to Mark and Luke, there is no explicit mention of the present time, the restitution of all that the followers of Jesus left behind is thus pushed forward to the future, in which they will take over the reigns with the Son of Man. The promise features the rare term “palingenesis”, whose precise temporal and factual determination cannot be deduced from the sentence itself. While in Mt 19:28 palingenesis is, according to the prevailing interpretation, a synonym for the future restoration of the universe, in Tit 3:5 (the only other occurrence in the NT) the same word refers to the rebirth of some people that took place in the past (at baptism). Even non-biblical literature does not provide a clear precedent - palingenesis tends to be set both in the past and in the future, it concerns both the world and individuals or groups (Israel). – The syntax and punctuation of the Greek sentence show that both interpretations are equally possible: palingenesis can be related either (A) to the following verbal form “sitting (the Son of Man on the throne)”, i.e. to the future, or (B) to the preceding verbal form “following (disciples behind Jesus)”, i.e. into the past, in addition, there is a third, open option (C). In the 16th-century Greek, Latin, and Czech versions, all possibilities are represented: Erasmus punctuates the Vulgate differently (B), Beza first respects the Vulgate (A), but in his Annotations he considers the second solution (B), in the fourth and fifth editions he finally leaves the matter open (C), two Czech translations from the first half of the 16th century (Náměšť 1533, Melantrich 1556/57) hesitate in the dilemma between the Vulgate and Erasmus (C), most Brethren translations starting with Blahoslav (1564) deviate from the Vulgate (B), only the Six-Volume Kralice Bible from 1593/94 (“Kralická Šestidílka”) hesitates (C), in “Kralická Šestidílka” and in the Kralice New Testament from 1601 the Brethren pay equal attention to both interpretations in a rather extensive note, which, for its balance, is a nice proof of intellectual openness and tolerance. Like Beza, the Brethren add a new aspect to interpretation (B): palingenesis can mean the renewal of the whole world thanks to the Gospel and the first coming of the Messiah. – Considering the dynamic development in the 16th century, it is surprising that all ten tracked Czech translations from around the 20th century agree on only one variant (A). Option (B) seems to be in danger of unfair oblivion. Therefore, in conclusion, we allow ourselves to propose a new, somewhat looser translation or paraphrase of verse Mt 19:28 in the spirit of Kralice: “Amen, I say to you, it was you who followed me when I came to renew the world with the gospel, and when the Son of Man sits on the throne of his glory, it will be you again who will sit on twelve thrones and judge the twelve tribes of Israel.”
Keywords:
palingenesis; Gospel of Matthew; Kralice Bible; Erasmus of Rotterdam; Theodore Beza; Vulgate; Czech Bible translations
Available at various institutes of the ASCR
Palingeneze - obnovení všeho? (Matouš 19,28)
V Matoušově verzi Ježíšova zaslíbení (Mt 19,28–30) oproti Markovi a Lukášovi chybí výslovná zmínka o přítomnosti: restituce všeho, co Ježíšovi následovníci opustili, se tak posouvá až do budoucnosti, ...
Česká putování za Richardem Wagnerem
Fránek, Michal; Kopecký, J.
2024 - Czech
Studie zkoumá fenomén českých cest za slavným německým skladatelem Richardem Wagnerem a do míst spojených s jeho kultem (Mnichov, Bayreuth, Curych atd.). Zaměřuje se na wagnerovské cesty – uskutečněné i neuskutečněné – českých skladatelů (Bedřich Smetana, Antonín Dvořák, Zdeněk Fibich, Josef Bohuslav Foerster), interpretů (Ema Destinnová, Karel Burian aj.), hudebních kritiků (Otakar Hostinský, V. V. Zelený), malířů (Jaroslav Čermák) a spisovatelů (Julius Zeyer, Jaroslav Maria, Teréza Nováková), přičemž sleduje jejich různé motivace. The study explores the phenomenon of Czech travels to famous German composer Richard Wagner and to the places associated with his cult (Munich, Bayreuth, Zurich, etc.). It focuses on the Wagnerian journeys – accomplished and not – of Czech composers (Bedřich Smetana, Antonín Dvořák, Zdeněk Fibich, Josef Bohuslav Foerster), performers (Ema Destinnová, Karel Burian, etc.), music critics (Otakar Hostinský, V. V. Zelený), painters (Jaroslav Čermák) and writers (Julius Zeyer, Jaroslav Maria, Teréza Nováková), tracing their different motivations.
Keywords:
Richard Wagner; travelling to artists
Available at various institutes of the ASCR
Česká putování za Richardem Wagnerem
Studie zkoumá fenomén českých cest za slavným německým skladatelem Richardem Wagnerem a do míst spojených s jeho kultem (Mnichov, Bayreuth, Curych atd.). Zaměřuje se na wagnerovské cesty – uskutečněné ...
Verification of the dynamic properties of a new model turbine wheel with free blades
Voronova, Evgeniya; Procházka, Pavel; Maturkanič, Dušan; Mekhalfia, Mohammed Lamine; Hodboď, Robert
2024 - English
The paper describes a new experimental model of turbine wheel with free blades. Verification tests were carried out using a Doppler laser vibrometer, with a focus on the equipment parameters under various conditions. The measurements were performed in the Laboratory of Rotational Laser Vibrometry originated at the Institute of Thermomechanics AS CR, v.v.i.
Keywords:
natural frequencies; vibration; blade; laser; turbine
Available at various institutes of the ASCR
Verification of the dynamic properties of a new model turbine wheel with free blades
The paper describes a new experimental model of turbine wheel with free blades. Verification tests were carried out using a Doppler laser vibrometer, with a focus on the equipment parameters under ...
Reaction Mechanisms of Psychoactive Compounds
Sokolová, Romana; Beneš, Marek; Jiroušková, Eliška; Degano, I.
2024 - English
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.
Keywords:
oxidation; reduction; IR spectrochemistry
Available on request at various institutes of the ASCR
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 ...
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Vaněčková, Eva; Šikula, M.; Hrdlička, Vojtěch; Sebechlebská, Táňa; Kolivoška, Viliam
2024 - English
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. Commercially\navailable SEC cells most often have an incorporated platinum working electrode, which can limit the range of the usable potential window and, in addition, can complicate the analysis due to the\nabsorption phenomenon. In this work, we designed and manufactured two types of custom-made SEC cells employing optically transparent carbon-based working electrodes for UV-Vis monitoring of reactants and electrogenerated intermediates and products. The first SEC cell is entirely manufactured by 3D printing using fused deposition modeling (FDM) by combining optically transparent (PET) and electrically conductive (PLA-CB) filaments. The second SEC cell employs pencil graphite (PG) rods as the working electrode (PGE) and its body is manually assembled from quartz slides. The functionality of the FDM 3D printed SEC cell and manually assembled quartz SEC cell were verified by cyclic voltammetry with in situ UV-Vis spectroscopic absorption monitoring of ruthenium(III) acetylacetonate (Ru(ac)3) redox-active probe dissolved in an aqueous or non-aqueous deaerated solvent, respectively. Both presented cells enable complete redox reversible conversion and strictly oxygen-free conditions.
Keywords:
pencil graphite electrode; spectroelectrochemistry; 3D printed electrode
Available on request at various institutes of the ASCR
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. ...
Modification of cooling system for laboratory measurement of rotor blade vibration
Maturkanič, Dušan; Procházka, Pavel; Hodboď, Robert; Voronova, Evgeniya; Mekhalfia, Mohammed Lamine
2024 - English
Last year, the replacement of the turbine wheel model was completed in the Laboratory of Rotational Laser Vibrometry of the Institute of Thermomechanics AS CR, v.v.i. Based on previous experience and the expected higher operating load planned for the new wheel, the cooling system was modified at the same time. The paper describes the main effort in this direction and the results that clarify the previous damage of the measuring device.
Keywords:
blade; vibration; cooling system; measurement; laboratory
Available at various institutes of the ASCR
Modification of cooling system for laboratory measurement of rotor blade vibration
Last year, the replacement of the turbine wheel model was completed in the Laboratory of Rotational Laser Vibrometry of the Institute of Thermomechanics AS CR, v.v.i. Based on previous experience and ...
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 ...
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
Other bases