Publications at the Department of Mathematics and Natural Sciences from 2019

Please note, the Hochschulbibliographie has the data status 07/31/2024.
All newer entries can be found in the University Bibliography of Technische Universität Ilmenau (TUUniBib).

Results: 937
Created on: Wed, 18 Sep 2024 18:54:08 +0200 in 0.0897 sec


Rakhmanov, Saparboy; Trunk, Carsten; Matrasulov, Davronbek
Quantum particle under dynamical confinement: from quantum fermi acceleration to high harmonic generation. - In: Physica scripta, ISSN 1402-4896, Bd. 99 (2024), 7, 075308, S. 1-13

Quantum dynamics of a particle confined in a box with time-dependent wall is revisited by considering some unexplored aspects of the problem. In particular, the case of dynamical confinement in a time-dependent box in the presence of purely time-varying external potential is treated by obtaining exact solution. Also, some external potentials approving separation of space and time variables in the Schrödinger equation with time-dependent boundary conditions are classified. Time-dependence of the average kinetic energy and average quantum force are analyzed. A model for optical high harmonic generation in the presence of dynamical confinement and external monochromatic time-dependent homogeneous electric field is proposed.



https://doi.org/10.1088/1402-4896/ad52c8
Behrndt, Jussi; Schmitz, Philipp; Teschl, Gerald; Trunk, Carsten
Perturbation and spectral theory for singular indefinite Sturm-Liouville operators. - In: Journal of differential equations, ISSN 1090-2732, Bd. 405 (2024), S. 151-178

https://doi.org/10.1016/j.jde.2024.05.043
Motuziuk, Olexandr; Nozdrenko, Dmytro; Prylutska, Svitlana; Vareniuk, Igor; Cherepanov, Vsevolod; Bogutska, Kateryna; Rudenko, Sergii; Prylutskyy, Yuriy; Piosik, Jacek; Ritter, Uwe
C60 fullerene reduces the level of liver damage in chronic alcohol intoxication of rats. - In: Molecules, ISSN 1420-3049, Bd. 29 (2024), 13, 2951, S. 1-15

The liver is the main organ responsible for the metabolism of ethanol, which suffers significantly as a result of tissue damage due to oxidative stress. It is known that C60 fullerenes are able to efficiently capture and inactivate reactive oxygen species in in vivo and in vitro systems. Therefore, the purpose of this study is to determine whether water-soluble C60 fullerene reduces the level of pathological process development in the liver of rats induced by chronic alcohol intoxication for 3, 6, and 9 months, depending on the daily dose (oral administration; 0.5, 1, and 2 mg/kg) of C60 fullerene throughout the experiment. In this context, the morphology of the C60 fullerene nanoparticles in aqueous solution was studied using atomic force microscopy. Such biochemical parameters of experimental animal blood as ALT (alanine aminotransferase), AST (aspartate aminotransferase), GGT (gamma-glutamyl transferase) and ALP (alkaline phosphatase) enzyme activities, CDT (carbohydrate-deficient transferrin) level, values of pro-antioxidant balance indicators (concentrations of H2O2 (hydrogen peroxide) and GSH (reduced glutathione), activities of CAT (catalase), SOD (superoxide dismutase) and GPx (selenium-dependent glutathione peroxidase)), and pathohistological and morphometric features of liver damage were analyzed. The most significant positive change in the studied biochemical parameters (up to 29 ± 2% relative to the control), as markers of liver damage, was recorded at the combined administration of alcohol (40% ethanol in drinking water) and water-soluble C60 fullerenes in the optimal dose of 1 mg/kg, which was confirmed by small histopathological changes in the liver of rats. The obtained results prove the prospective use of C60 fullerenes as powerful antioxidants for the mitigation of pathological conditions of the liver arising under prolonged alcohol intoxication.



https://doi.org/10.3390/molecules29132951
Ilchmann, Achim; Kirchhoff, Jonas; Schaller, Manuel
Port-Hamiltonian descriptor systems are relative generically controllable and stabilizable. - In: Mathematics of control, signals, and systems, ISSN 1435-568X, Bd. 0 (2024), 0, insges. 37 S.

The present work is a successor of Ilchmann and Kirchhoff (Math Control Signals Syst 33:359-377, 2021) on generic controllability and of Ilchmann and Kirchhoff (Math Control Signals Syst 35:45-76, 2022) on relative generic controllability of linear differential-algebraic equations. We extend the result from general, unstructured differential-algebraic equations to differential-algebraic equations of port-Hamiltonian type. We derive results on relative genericity. These findings are the basis for characterizing relative generic controllability of port-Hamiltonian systems in terms of dimensions. A similar result is proved for relative generic stabilizability.



https://doi.org/10.1007/s00498-024-00392-7
Bai, Yajie; Fang, Zhenyuan; Lei, Yong; Liu, Lijing; Zhao, Huaiquan; Bai, Hongye; Fan, Weiqiang; Shi, Weidong
FCF-LDH/BiVO4 with synergistic effect of physical enrichment and chemical adsorption for efficient reduction of nitrate. - In: Green energy & environment, ISSN 2468-0257, Bd. 9 (2024), 7, S. 1112-1121

Photoelectrochemical NO3− reduction (PEC NITRR) not only provides a promising solution for promoting the global nitrogen cycle, but also converts NO3− to the important chemicals (NH3). However, it is still a great challenge to prepare catalysts with excellent NO3− adsorption/activation capacity to achieve high NITRR. Herein, we designed a novel Fe2+Cu2+Fe3+LDH/BiVO4 (FCF-LDH/BVO) catalyst with synergistic effect of chemical adsorption and physical enrichment. Fe2+ in FCF-LDH/BVO provides the rich Lewis acid sites for the adsorption of NO3−, and the appropriate layer spacing of FCF-LDH further promotes the physical enrichment of NO3− in its interior, thus realizing the effective contact between NO3− and active sites (Fe2+). FCF-LDH/BVO showed excellent NH3 production performance (FENH3 = 66.1%, rNH3 = 13.8 μg h−1 cm−2) and selectivity (FENO2- = 2.5%, rNO2- = 4.9 μg h−1 cm−2) in 0.5 mol L−1 Na2SO4 electrolyte. In addition, FCF-LDH/BVO maintains the desirable PEC stability for six cycle experiments, showing great potential for practical application. The 14NO3− and 15NO3− isotope test provides strong evidence for further verification of the origin of N in the generated NH3. This LDH catalyst has a great potential in PEC removal of NO3− from groundwater.



https://doi.org/10.1016/j.gee.2023.05.011
Néel, Nicolas; Dreßler, Christian; Kröger, Jörg
Effect of orbital symmetry on probing the single-molecule Kondo effect. - In: Physical review, ISSN 2469-9969, Bd. 109 (2024), 24, L241401, S. L241401-1-L241401-6

The low-energy excitation spectrum of a metal-free phthalocyanine molecule on Ag(111) is probed in scanning tunneling spectroscopy experiments. The use of functionalized p-orbital and s-orbital tips leads to markedly different results. While CO-terminated p-wave tips probe the zero-energy Abrikosov-Suhl resonance induced by the molecular Kondo effect, Ag-coated s-wave tips - in strong contrast - feign the absence of the Kondo effect due to a missing Abrikosov-Suhl resonance. Reducing the vertical distance between the s-orbital tip and the molecule progressively unveils the resonance, compatible with findings for the p-orbital tip in the far tunneling range. A mechanism based on orbital overlap is suggested as the tentative origin of the observations. The CO-functionalized tip is then used to explore the altered Kondo effect of the tautomerized phthalocyanine.



https://doi.org/10.1103/PhysRevB.109.L241401
Berger, Thomas; Dennstädt, Dario
Funnel MPC for nonlinear systems with arbitrary relative degree. - In: Automatica, ISSN 0005-1098, Bd. 167 (2024), 111759, S. 1-10

The model predictive control (MPC) scheme funnel MPC enables output tracking of smooth reference signals with prescribed error bounds for nonlinear multi-input multi-output systems with stable internal dynamics. Earlier works achieved the control objective for system with relative degree restricted to one or incorporated additional feasibility constraints in the optimal control problem. Here we resolve these limitations by introducing a modified stage cost function relying on a weighted sum of the tracking error derivatives. The weights need to be sufficiently large and we state explicit lower bounds. Under these assumptions we are able to prove initial and recursive feasibility of the novel funnel MPC scheme for systems with arbitrary relative degree - without requiring any terminal conditions, a sufficiently long prediction horizon or additional output constraints.



https://doi.org/10.1016/j.automatica.2024.111759
Lauer, Kevin; Müller, Robin; Peh, Katharina; Schulze, Dirk; Krischok, Stefan; Reiß, Stephanie; Frank, Andreas; Ortlepp, Thomas
Investigation of Tl-doped silicon by low-temperature photoluminescence during light-induced degradation treatments. - In: Physica status solidi, ISSN 1862-6319, Bd. n/a (2024), n/a, 2400287, S. 1-6

Scientific progress is made in understanding photoluminescence (PL) lines in thallium-doped silicon. Two PL lines called A and P, which appear after quenching, are found to exhibit irreversible as well as reversible behavior under the application of light-induced degradation (LID) treatments. The reversible behavior is similar to changes of a P line in indium-doped silicon due to LID treatments, which have led to the identification of this P line to be caused by an InSi-Sii-defect. By exploiting the metastability of defects from the ASi-Sii category, the experimental findings of this study indicate that the underlying defect for the A and P line in thallium-doped silicon is the TlSi-Sii-defect.



https://doi.org/10.1002/pssa.202400287
Kronfeld, Klaus-Peter; Köhler, Michael; Ellinger, Thomas
Microfluidic synthesis and properties of thermoresponsive hydrogel core-shell particles. - In: Journal of composites science, ISSN 2504-477X, Bd. 8 (2024), 5, 162, S. 1-9

An approach is demonstrated for the generation of swellable core-shell particles in the sub-millimeter range using a one-step microfluidic method. Particles are made of an agarose gel core and a shell consisting of hydrogel based on crosslinked poly-(N-isopropylacrylamide) (PNIPAM). Solidification of the core was achieved by cooling below the sol-gel temperature, while the shell was cured by photoinitiated co-polymerization. The shell of the particles is reversibly thermoresponsive; it contracts upon heating, releasing water, and becomes hydrophobic. The transition temperature as well as the stability of the particles are mainly affected by the shell monomer composition, while they are less affected by the type of the core material. Such composite particles remain swellable after drying.



https://doi.org/10.3390/jcs8050162
Cao, Kang-Zhe; Ma, Jia-Hui; Dong, Yu-Lian; Duan, Yu; Zheng, Run-Tian; Bundhooa, Dharani; Liu, Hui-Qiao; Lei, Yong
Graphitic carbons: preparation, characterization, and application on K-ion batteries. - In: Rare metals, ISSN 1867-7185, Bd. 43 (2024), 9, S. 4056-4075

K-ion batteries (KIBs) have drawn much attention due to the abundant potassium reserves and wide accessibility as well as high energy density, which can be designed for large-scale energy storage systems. As the most promising anode materials for KIBs, graphitic carbons, especially those with an intermediate structure between the crystalline graphite and amorphous carbons become a hot research focus because of the improved rate capability and enhanced diffusion-controlled capacity at low voltage regions. Herein, we first review the structures of graphitic carbons in the view of graphitic domains and the structure changes in their K-ion intercalation compounds. Then, we summarize the preparation mechanisms and characterizations of graphitic carbons and the influence factors in their degree of graphitization. Furtherly, we illustrate the strategies to optimize their K-ion storage properties from four aspects, namely graphitic domain design, microstructure engineering, electrochemical active component regulation, and defect engineering. Finally, we propose the issues that urgently need to be solved in graphitic carbons and the possible solutions. We hope that this view could offer some inspiration for the further designing and optimizing of graphitic carbons for practical KIBs.



https://doi.org/10.1007/s12598-024-02764-z