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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
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
Lanthanide Complexes (Ln=La, Nd, Dy) of Octaethyl propane-1,1,3,3-tetrayltetrakis(phosphonate): Multidentate Binding Competing with Monodentate DMSO Complexes
(2022-12-09)
The preparation of lanthanide nitrate complexes [Ln(NO₃)₃{L}]ₙ (Ln³+=La, Nd, Dy) supported by the octaethyl propane-1,1,3,3-tetrayltetrakis(phosphonate) (L) chelate ligand platform is presented. Re-crystallization of these compounds from DMSO/THF led to a complete replacement of the multidentate phosphonate ester ligand and the formation of exclusively DMSO-supported lanthanide nitrate species [Ln(NO₃)₃(DMSO)₄]. The relative basicity of a model phosphonate ester vs. DMSO is explored with theoretical means, pointing ...
Aufsatz
Spatial and Temporal Variations of Stable Isotopes in Precipitation in the Mountainous Region, North Hesse
(2022-12-01)
Patterns of stable isotopes of water (¹⁸O and ²H) in precipitation have been used as tracers for analyzing environmental processes which can be changed by factors such as the topography or meteorological variables. In this study, we investigated the isotopic data in precipitation for one year in the low mountain range of North Hesse, Germany, and analyzed mainly for altitude, rainfall amount, and air temperature effects on a regional scale. The results indicate that the isotopic composition expressed an altitude ...
Aufsatz
Reversible Photo-Induced Reshaping of Imprinted Microstructures Using a Low Molecular Azo Dye
(2022-01-31)
A blend of low molecular azo glass (AZOPD) and polystyrene (PS) were used for the systematic investigation of photo-induced stretching and recovery of nanoimprinted structures. For this purpose, light and heat was used as recovery stimuli. The AZOPD/PS microstructures, fabricated with thermal nanoimprint lithography (tNIL), comprises three different shapes (circles, crosses and squares) and various concentrations of AZOPD fractions. The results show a concentrationdependent reshaping. Particularly the sample with 43 ...
Aufsatz
Reactions of Mesityl Azide with Ferrocene-Based N-Heterocyclic Germylenes, Stannylenes and Plumbylenes, Including PPh₂-Functionalised Congeners
(2022-05-05)
The active PbII/P Lewis pair nature of a PPh₂-functionalised ferrocene-based N-heterocyclic plumbylene is demonstrated by its reaction with mesityl azide to afford a phosphazide, which is in contrast to the inertness of the unfunctionalised congener. The lighter analogues most likely react with MesN₃ at their respective tetrel atom Eᴵᴵ, leading to the formation of N₂ and an Eᶦᵛ=NMes unit, followed by NMes transfer from the Eᶦᵛ to the Pᴵᴵᴵ atom.
The reactivity of ferrocene-based N-heterocyclic tetrylenes ...
Aufsatz
Asymmetrically Substituted Phospholes as Ligands for Coinage Metal Complexes
(2022-05-24)
A series of coinage metal complexes asymmetrically substituted 2,5-diaryl phosphole ligands is reported. Structure, identity, and purity of all obtained complexes were corroborated with state-of-the-art techniques (multinuclear NMR, mass spectrometry, elemental analysis, X-ray diffraction) in solution and solid state. All complexes obtained feature luminescence in solution as well as in the solid state. Additionally, DOSY-MW NMR estimation experiments were performed to achieve information about the aggregation behavior ...
Aufsatz
Synthesis of Geminal Bis- and Tetrakisphosphonate Ester Derivatives and Their Coordination Behavior Towards Ca(II) Ions
(2022-04-05)
Geminal Bisphosphonate (BP) Esters in Ca(II) Ion Coordination. A series of geminal BPs was prepared starting from their corresponding ethyl- or isopropyl (arylmethylene)phosphonate ester precursors. Complexation with CaCl₂ yields the derived coordination compounds [Ca(H₂O)₂(L1–L3)₂]Cl₂ or [Ca(L8)Cl₂]ₙ. Their structures in the solid- (SCXRD) as well as solution-state (¹H DOSY NMR) are evaluated and comprehensively compared to literature data.
The preparation and thorough characterization of a variety of (arylmethy ...