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Aufsatz
Influence of Accelerated Aging on the Fiber-Matrix Adhesion of Regenerated Cellulose Fiber-Reinforced Bio-Polyamide
(2023-03-23)
With regard to the sustainability and biological origin of plastic components, regenerated cellulose fiber (RCF)-reinforced polymers are expected to replace other composites in the future. For use under severe conditions, for example, as a housing in the engine compartment, the resistance of the composites and the impact on the fiber and fiber-matrix adhesion must be investigated. Composites of bio-polyamide with a reinforcement of 20 wt.% RCF were compounded using a twinscrew extruder. The test specimens were ...
Aufsatz
Leaching and Transformation of Perfluoroalkyl Acids and Polyfluoroalkyl Phosphate Diesters in Unsaturated Soil Column Studies
(2022-06-25)
Per- and polyfluoroalkyl substances (PFAS) are environmentally ubiquitous, anthropogenic substances with adverse effects on organisms, which shows the need to study their environmental fate and leaching behavior. In the present soil columns study, the leaching behavior and fate of nontransformable and transformable (precursors) were investigated. Ten nontransformable PFAS in two different soils, two precursors and two field soils, which were already contaminated with a mixture of PFAS, and two uncontaminated controls, ...
Aufsatz
Experimental analysis of liquid metal galinstan for electronics actuation
(2022-06-05)
The experimental interfacial tension measurements of galinstan as a function of applied DC voltages are presented. The measurements are based on a tailored, modified pendent drop setup to make it suitable for this experiment. The findings rationalise Galinstan corresponding to Marangoni flow that actuates under the influence of a change in interfacial tension, resulting from applied voltages. Galinstan is substantiated as an actuation medium to enable ON or OFF states by using a very low applied voltage (∼ 0.8V). The ...
Aufsatz
A Stable Crystalline N-Heterocyclic Carbene with a 1,1’ - Ferrocenylene Backbone and Benzylic N-Substituents
(2022-12-08)
Two ferrocene-based NHCs of the type fc[(NR)₂C:] (1ᴿ; fc=1,1’-ferrocenylene) containing benzylic N-substituents were synthesised from the corresponding formamidinium compounds 1ᴿH[BF₄] by reaction with LiN(SiMe₃)₂. In the case of R=CH₂Ph (Bn), the carbene was characterised through trapping reactions with sulfur and selenium, which afforded fc[(NBn)₂CS] (1ᴮⁿS) and fc[(NBn)₂CSe] (1ᴮⁿSe), respectively. A thermally stable carbene was obtained with R=CH₂Mes (Bn*). Its reaction with sulfur and selenium afforded fc[(NBn*)₂CS] ...
Aufsatz
Theoretical study of spin polarization in multiphoton ionization of Xe
(2023-04-21)
Spin polarization in the multiphoton above-threshold ionization of 5p3/2- and 5p1/2-electrons of Xe with intense 395nm, circularly polarized laser pulses, is investigated theoretically. For this purpose, we solve the time-dependent Schrödinger equation on the basis of spherical spinors. We, thus, simultaneously propagate the spin-up and spin-down single-active-electron wave packets, driven by the laser pulses in the ionic potential, which includes the spin–orbit interaction explicitly. The present theoretical results ...
Aufsatz
Comparative Life Cycle Assessment of Carbon Dioxide Mineralization Using Industrial Waste as Feedstock to Produce Cement Substitutes
(2023-05-16)
The mineralization of carbon dioxide offers a way to permanently sequester carbon while producing construction materials, combining the concepts of carbon capture and utilization (CCU) and carbon capture and storage (CSS). However, it is important to evaluate different mineralization processes in terms of their environmental impact. This study provides the first comparative life cycle assessment (LCA) analysis that focuses on the utilization of industrial waste materials. We analyzed the climate and material footprint ...
Aufsatz
Effects of Mangosteen Peel Phenolic Compounds on Tilapia Skin Collagen-Based Mineralized Scaffold Properties
(2022-09-16)
A proper valorization of biological waste sources for an effective conversion into composites for tissue engineering is discussed in this study. Hence, the collagen and the phenolic compound applied in this investigation were extracted from waste sources, respectively, fish industry rejects and the peels of the mangosteen fruit. Porous scaffolds were prepared by combining both components at different compositions and mineralized at different temperatures to evaluate the modifications in the biomimetic formation of ...
Aufsatz
Analysis and Validation of Varied Simulation Parameters in the Context of Thermoplastic Foams and Special Injection Molding Processes
(2023-04-28)
The simulation solutions of different plastic injection molding processes are as multifaceted as the field of injection molding itself. In this study, the simulation of a special injection molding process, which generates partially foamed integral components, was parameterized and performed. This partial and physical foaming is realized by a defined volume expansion of the mold cavity. Using the injection molding simulation software Moldex 3D, this so-called Pull and Foam process was digitally reconstructed and ...
Aufsatz
Ferrocene-Based N-Heterocyclic Plumbylenes [Fe{(η⁵- C₅H₄)NSiMe₂R}₂Pb:]: Influence of the Steric Demand of the NSubstituents on Their Dimerization via C-H Activation with Pbᴵᴵ
(2023-05-12)
Ferrocene-based N-heterocyclic plumbylenes fc[(NSiMe₂R)₂Pb:] (1; fc=1,1’-ferrocenylene) are easily accessible by transamination from [(Me₃Si)₂N]₂Pb and the corresponding 1,1’-diaminoferrocene derivatives fc(NHSiMe₂R)₂. They may form unconventional dimers 2 by a process, which causes the cleavage of a cyclopentadienyl C−H bond and the formation of a Pb−C and an N−H bond. The monomer-dimer equilibrium (2 1⇆2) has been addressed experimentally and computationally. It critically depends on the steric demand of the ...
Aufsatz
Observation of a Long-lived Electronic Coherence Modulated by Vibrational Dynamics in Molecular Nd³+- Complexes at Room Temperature
(2023-03-23)
Temporally delayed, phase-locked coherent pairs of near IR femtosecond laser pulses were employed to study electronic coherences in molecular Nd³+-complexes at room temperature. Dissolved and solid complexes were studied under a confocal microscope set-up with fluorescence detection. The observed electronic coherence on a few hundred femtoseconds time scale is modulated by additional coherent wave packet dynamics, which we attribute mainly to be vibrational in nature. In future, the complexes may serve as prototypes ...