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search.filters.applied.f.access: openAccess × DDC: 540 × Type: Article × Type: Text × Publisher: Weinheim : Wiley-VCH Verl. × WGL Institute: IPF ×

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    Funktionalisierte Kern-Schale-Partikel als Träger zur Enzymimmobilisierung und deren Anwendung
    (Weinheim : Wiley-VCH Verl., 2020) Matura, Anke; Köpke, Dorina; Marschelke, Claudia; Kramer, Julius; Synytska, Alla; Sallat, Marco
    Mono- und bifunktionale hybride Kern-Schale-Partikel wurden für die Enzymimmobilisierung eingesetzt. An monofunktionalen Poly(2-dimethylamino)ethylmethacrylat-modifizierten Partikeln wurden die idealen Bedingungen für die Immobilisierung untersucht. Anschließend erfolgte die Übertragung auf bifunktionale Janus-Partikel-Systeme, mit denen gleichzeitig die schaltbare Abtrennung und der erneute Einsatz der Enzyme möglich waren. Abschließend wurde der mehrfache Einsatz der enzymbeladenen Partikel modellhaft am Beispiel der Prozesswasserentfärbung aus der Textilindustrie mit Laccase gezeigt und eine Kostenrechnung durchgeführt.
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    Characterization of the state of dispersion of carbon nanotubes in polymer nanocomposites
    (Weinheim : Wiley-VCH Verl., 2011) Buschhorn, Samuel T.; Wichmann, Malte H. G.; Sumfleth, Jan; Schulte, Karl; Pegel, Sven; Kasaliwal, Gaurav R.; Villmow, Tobias; Krause, Beate; Göldel, Andreas; Pötschke, Petra
    A practical overview of possibilities and limits to characterize the state of dispersion of carbon nanotubes (CNT) in polymer based nanocomposites is given. The most important and widely available methods are discussed with practical employment in mind. One focus is the quantitative characterization of the state of dispersion in solid samples using microscopy techniques such as optical microscopy or transmission electron microscopy. For dispersions of CNTs in aqueous media, solvents or monomers a sedimentation analysis is presented. This way dispersability and dispersion state of CNTs can be assessed. Indirect methods such as electrical conductivity measurements and rheological tests, dynamic differential scanning calorimetry and mechanical test are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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    Methods to characterize the dispersability of carbon nanotubes and their length distribution
    (Weinheim : Wiley-VCH Verl., 2012) Krause, Beate; Mende, Mandy; Petzold, Gudrun; Boldt, Regine; Pötschke, Petra
    Two main properties of carbon nanotube (CNT) materials are discussed in this contribution. First, a method to characterize the dispersability of CNT materials in aqueous surfactant solutions in presented, which also allows conclusions towards the dispersability in other media, like polymer melts. On the other hand it is shown, how the length of CNTs before and after processing, e.g., after melt mixing with thermoplastics, can be quantified. Both methods are illustrated with examples and the practical relevance is shown. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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    Continuous Flow Synthesis of Azoxybenzenes by Reductive Dimerization of Nitrosobenzenes with Gel‐Bound Catalysts
    (Weinheim : Wiley-VCH Verl., 2021) Schmiegel, Carsten J.; Berg, Patrik; Obst, Franziska; Schoch, Roland; Appelhans, Dietmar; Kuckling, Dirk
    In the search for a new synthetic pathway for azoxybenzenes with different substitution patterns, an approach using a microfluidic reactor with gel-bound proline organocatalysts under continuous flow is presented. Herein the formation of differently substituted azoxybezenes by reductive dimerization of nitrosobenzenes within minutes at mild conditions in good to almost quantitative yields is described. The conversion within the microfluidic reactor is analyzed and used for optimizing and validating different parameters. The effects of the different functionalities on conversion, yield, and reaction times are analyzed in detail by NMR. The applicability of this reductive dimerization is demonstrated for a wide range of differently substituted nitrosobenzenes. The effects of these different functionalities on the structure of the obtained azoxyarenes are analyzed in detail by NMR and single-crystal X-ray diffraction. Based on these results, the turnover number and the turnover frequency were determined.