Publikační činnost akademických pracovníků FChT / FChT Research Outputs
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Článek Omezený přístup peer-reviewedpostprint Carbon dioxide mid-infrared sensing based on Dy3+-doped chalcogenide waveguide photoluminescence(Optical Society of America, 2023) Bodiou, Loic; Baillieul, Marion; Nazabal, Virginie; Lemaitre, Jonathan; Benardais, Albane; Meziani, Sofiane; Lorrain, Nathalie; Dumeige, Yannick; Němec, Petr; Charrier, JoelClimate-active gases, notably carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), display fundamental absorption bands in the mid-infrared (mid-IR). The detection and monitoring of those gases could be enabled by the development of mid-IR optical sources. Broadband mid-IR on-chip light emission from rare-earth-doped chalcogenide photonic integrated circuits could provide a compact, efficient, and cost-effective gas sensing solution. Mid-IR photoluminescence of dysprosium-doped selenide ridge waveguides obtained under optical pumping at a telecommunication wavelength (1.3 mu m) is investigated for Dy3+ ion concentrations in the 2500-10,000 ppmw range. CO2 detection at around 4.3 mu m is then demonstrated based on absorption of this broadband mid-IR emission.Článek Omezený přístup peer-reviewedpostprint Defect pairing in Fe-doped SnS van der Waals crystals: a photoemission and scanning tunneling microscopy study(Royal Society of Chemistry, 2023) Yesilpinar, Damla; Vondracek, Martin; Čermák, Patrik; Monig, Harry; Kopecek, Jaromir; Caha, Ondrej; Carva, Karel; Drašar, Čestmír; Honolka, JanWe investigate the effect of low concentrations of iron on the physical properties of SnS van der Waals crystals grown from the melt. By means of scanning tunneling microscopy (STM) and photoemission spectroscopy we study Fe-induced defects and observe an electron doping effect in the band structure of the native p-type SnS semiconductor. Atomically resolved and bias dependent STM data of characteristic defects are compared to ab initio density functional theory simulations of vacancy (V-S and V-Sn), Fe substitutional (Fe-Sn), and Fe interstitial (Fe-int) defects. While native SnS is dominated by acceptor-like V-Sn vacancies, our results show that Fe preferentially occupies donor-like interstitial Fe-int sites in close proximity to V-Sn defects along the high-symmetry c-axis of SnS. The formation of such well-defined coupled (V-Sn, Fe-int) defect pairs leads to local compensation of the acceptor-like character of V-Sn, which is in line with a reduction of p-type carrier concentrations observed in our Hall transport measurements.Článek Omezený přístup peer-reviewedpostprint Structural, vibrational, and electronic behavior of two GaGeTe polytypes under compression(Elsevier Science BV, 2023) Bandiello, E; Gallego-Parra, S; Liang, A; Sans, J. A; Cuenca-Gotor, V; da Silva, E. Lora; Vilaplana, R; Rodriguez-Hernandez, P; Munoz, A; Diaz-Anichtchenko, D; Popescu, C; Alabarse, F. G; Rudamas, C; Drašar, Čestmír; Segura, A; Errandonea, D; Manjon, F. JGaGeTe is a layered topological semimetal that has been recently found to exist in at least two different polytypes, a-GaGeTe (R3m) and b-GaGeTe (P63mc). Here we report a joint experimental and theoretical study of the structural, vibrational, and electronic properties of these two polytypes in high-pressure conditions. Both polytypes show anisotropic compressibility and two phase transitions, above 7 and 15 GPa, respectively, as confirmed by XRD and Raman spectroscopy measurements. Although the nature of the high-pressure phases could not be confirmed, comparison with other chalcogenides and total -energy calculations allow us to propose possible high-pressure phases for both polytypes with an in-crease in coordination for Ga and Ge atoms from 4 to 6. In particular, the simplification of the X-ray pattern for both polytypes above 15 GPa suggests a transition to a structure of relatively higher symmetry than the original one. This result is consistent with the rocksalt-like high-pressure phases observed in parent III-VI semiconductors, such as GaTe, GaSe, and InSe. Pressure-induced amorphization is observed upon pressure release. The electronic band structures of a-GaGeTe and b-GaGeTe and their pressure dependence also show similarities to III-VI semiconductors, thus suggesting that the germanene-like sublayer induces a semimetallic character in both GaGeTe polytypes. Above 3 GPa, both polytypes lose their topological features, due to the opening of the direct band gap, while the reduction of the interlayer space increases the thermal conductivity at high pressure. & COPY; 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Článek Omezený přístup peer-reviewedpostprint Podpora z fondů Evropské unie pro cukrovary v Česku (Financování rozvoje z evropských fondů a možnosti podpory v programovém období 2021+)(Výzkumný ústav cukrovarnický, 2023) Košťálová, Jana; Doskocil, Radek; Smolikova, Lenka; Lacko, BranislavZdroje, které byly k dispozici v minulých programových obdobích (PO) a budou k dispozici v začínajícím PO 2021–2027 z evropských fondů, jsou zajímavým zdrojem financování rozvojových aktivit cukrovarů zaměřených zejména na posun k udržitelnosti, digitalizaci, zavádění nejnovějších technologií, snižování energetické náročnosti a zlepšení podmínek pro zaměstnance. České cukrovary využily tuto možnost jak v PO 2017–2013, tak v PO 2014–2020 a jejich zapojení mělo zvyšující se tendenci. V nadcházejícím PO 2021–2027 budou mít možnost získat další podporu zejména z OP TAK a Zaměstnanost+. V současnosti je možné využít i výzev Národního plánu obnovy a je v zájmu cukrovarů se zorientovat i v možnostech podpory prostřednictvím integrovaných teritoriálních investic či přímo z programů na evropské úrovni. Důležité je nejen se seznámit s nabídkou programů a pravidly čerpání, ale také nepodcenit dovednost v oblasti projektového řízení, neboť to může významně přispět k úspěšnosti při podání žádosti i samotné realizaci projektů.Článek Omezený přístup peer-reviewedpostprint Application Potential of Trichoderma in the Degradation of Phenolic Acid-Modified Chitosan(MDPI, 2023) Swiontek Brzezinska, Maria; Kaczmarek-Szczepanska, Beata; Dabrowska, Grazyna B; Michalska-Sionkowska, Marta; Dembinska, Katarzyna; Richert, Agnieszka; Pejchalová, Marcela; Kumar, Sweta Binod; Kalwasinska, AgnieszkaThe aim of the study was to determine the potential use of fungi of the genus Trichoderma for the degradation of phenolic acid-modified chitosan in compost. At the same time, the enzymatic activity in the compost was checked after the application of a preparation containing a suspension of the fungi Trichoderma (spores concentration 10(5)/mL). The Trichoderma strains were characterized by high lipase and aminopeptidase activity, chitinase, and beta-1,3-glucanases. T. atroviride TN1 and T. citrinoviride TN3 metabolized the modified chitosan films best. Biodegradation of modified chitosan films by native microorganisms in the compost was significantly less effective than after the application of a formulation composed of Trichoderma TN1 and TN3. Bioaugmentation with a Trichoderma preparation had a significant effect on the activity of all enzymes in the compost. The highest oxygen consumption in the presence of chitosan with tannic acid film was found after the application of the consortium of these strains (861 mg O-2/kg after 21 days of incubation). Similarly, chitosan with gallic acid and chitosan with ferulic acid were found after the application of the consortium of these strains (849 mgO(2)/kg and 725 mg O-2/kg after 21 days of incubation). The use of the Trichoderma consortium significantly increased the chitinase activity. The application of Trichoderma also offers many possibilities in sustainable agriculture. Trichoderma can not only degrade chitosan films, but also protect plants against fungal pathogens by synthesizing chitinases and beta-1,3 glucanases with antifungal properties.Konferenční objekt Omezený přístup peer-reviewedpostprint Circular Activities of Major Norwegian Cities Communicated through their Websites(Univerzita Hradec Králové, 2023) Munzarová, Simona; Jelínková, Martina; Hoffman, MatthewThe transition to a circular economy entails the creation of new business models, brings new social changes, but also faces a number of challenges and opportunities to meet the goals of sustainable development. The importance of the circular economy has been growing in recent years also at the municipal level, and many large cities are in the phase of transition to a circular city. This paper presents the results of research aimed at identifying the circular activities of selected Norwegian cities, which are communicated through their official websites in order to analyze and evaluate the extent and level of circulation within the implemented activities. The aim is to describe the results of this research, to describe the activities implemented, the level of their communication, the circulation strategies used and to identify examples of good practice for use in other cities. The intention was to obtain at least a general overview of the current state of support for circular activities by municipalities in Norway, i.e. a country with an inspiring approach to the environment. The study shows that all monitored Norwegian cities are dedicated to the concept of circular economy, regardless of their size, the most frequently circularity strategy is Reduce.Konferenční objekt Omezený přístup peer-reviewedpostprint Indicators of Sustainable Production in Chemical Enterprises(AMCA, spol. s r.o., 2023) Vávra, Jan; Vrbická, TerezaThe growing pressure of the public on the sustainable behavior of companies is causing changes in the product portfolio as well as changes in production processes in all industries. The ongoing digitization of business processes facilitates production, helps monitor production processes, and ensures high quality and competitiveness. Chemical production companies are also adapting to the transformation of the industry and, even concerning the rising prices of resources, they are trying to produce sustainably. The sustainability of production and products needs to be monitored through appropriate indicators. Their use and utilization were mapped by qualitative research in a selected chemical company. The dimensions of sustainability were identified according to the triple-bottom-line concept and the key indicators of production sustainability evaluation were verified in them.Článek Omezený přístup peer-reviewedpostprint Application of Alkali Lignin and Spruce Sawdust for the Effective Removal of Reactive Dyes from Model Wastewater(MDPI, 2023) Hajkova, Katerina; Filipi, Michaela; Fojtik, Roman; Dorieh, AliToday, the emphasis is on environmentally friendly materials. Alkali lignin and spruce sawdust are suitable natural alternatives for removing dyes from wastewater. The main reason for using alkaline lignin as a sorbent is the recovery of waste black liquor from the paper industry. This work deals with removing dyes from wastewater using spruce sawdust and lignin at two different temperatures. The decolorization yields were calculated as the final values. Increasing the temperature during adsorption leads to higher decolorization yields, which may be due to the fact that some substances react only at elevated temperatures. The results of this research are useful for the treatment of industrial wastewater in paper mills, and the waste black liquor (alkaline lignin) can be used as a biosorbent.Článek Omezený přístup peer-reviewedpostprint Chemical pulp from corn stalks(2023) Hájková, Kateřina; Jurczyková, Tereza; Filipi, Michaela; Bouček, JiříThis work aimed to carry out chemical cooking of corn stalks, both in a nitrate-alkaline manner and in a soda pulp method. The composition of corn is characterized by cellulose, lignin, ash, and substances extractable into polar and organic solvents. Handsheets were made from the pulp, for which the degree of polymerization, sedimentation rate, and strength properties was determined.Článek Omezený přístup peer-reviewedpostprint Sorption of Halogenated Anti-Inflammatory Pharmaceuticals from Polluted Aqueous Streams on Activated Carbon: Lifetime Extension of Sorbent Caused by Benzalkonium Chloride Action(2023) Kamenická, Barbora; Weidlich, Tomáš; Pouzar, MiloslavThe enhancement of the adsorption capacity of activated carbon (AC) using benzalkonium chloride (BAC) within the adsorption of halogenated pharmaceuticals flufenamic acid (flufa) and diclofenac (dcf) was investigated in this study. An adsorption kinetic study was performed to evaluate the adsorption mechanisms. The adsorption mechanism of both drugs on granulated AC as well as saturated AC activated by BAC can be evaluated via pseudo-second kinetic order. The equilibrium adsorption capacity of spent granulated AC in co-action with BAC (qflufa = 195.5 mg g−1 and qdcf = 199.5 mg g−1) reached the adsorption capacity of virgin granulated AC (qflufa = 203.9 mg g−1 and qdcf = 200.7 mg g−1). Finally, batch and column arrangements were compared in an effort to possible practical application of exhausted AC in co-action with BAC. In both column and batch experiments, adsorption capacities of spent granulated AC for flufa increased using BAC by 170.4 mg g−1 and 560.4 mg g−1, respectively. The proposed mechanism of adsorption enhancement is the formation of less polar ion pairs and its better affinity to the non-polar AC surface. The drug concentrations were determined using the voltammetric method on carbon paste electrodes. The formation of ion pairs has been studied by the H1 NMR technique, and solubility in water of drugs and respective ion pairs were investigated using octan-1-ol/water coefficients (POW)