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10 Ergebnisse
Bereich: Suchergebnisse
Publikation Dynemicin analogs: Syntheses, methods of preparation and use(United States Patent and Trademark Office, 04.01.1994) Smith, Adrian L.; Hwang, Chan-Kou; Wendeborn, Sebastian; Nicolaou, Kyriacos C.; Schreiner, Erwin P.; Stahl, Wilhelm; Dai, Wei-Min; Maligres, Peter E.; Suzuki, ToshioA fused ring system compound is disclosed that contains an epoxide group on one side or the fused rings and an enediyne macrocyclic ring on the other side of the fused rings. The compounds have DNA-cleaving, antimicrobial and tumor growth-inhibiting properties. Chimeric compounds having the fused ring system compound as an aglycone bounded to (i) a sugar moiety as the ogligosaccharide portion or(ii) a monoclonal antibody or antibody combining site portion thereof that immunoreacts with target tumor cells are also disclosed. Compositions containing a compound or a chimer are disclosed, as are methods or preparing a compound.12 - PatentPublikation Enantiomeric dynemicin analogs, preparation and use thereof(World Intellectual Property Organization, 25.11.1993) Smith, Adrian L.; Wendeborn, Sebastian; Nicolaou, Kyriacos; Schreiner, Erwin P.; Dai, Wei-Min; Susuki, ToshioAn enantiomer of a fused ring system compound is disclosed that contains an epoxide group on one side of the fused rings and an enediyne macrocyclic ring on the other side of the fused rings. The enantiomeric compounds have DNA-cleaving, antimicrobial and tumor growth-inhibiting properties that are enhanced over their racemates. Chimeric compounds having the enantiomeric fused ring system compound as an aglycone bonded to (i) a sugar moiety as the oligosaccharide portion or (ii) a monoclonal antibody or antibody combining site portion thereof that immunoreacts with target tumor cells are also disclosed. Compositions containing an enatiomeric compound or an enantiomeric chimer are disclosed, as are methods of preparing an enantiomeric compound.12 - PatentPublikation Influence of pulping conditions on the pulp yield and fiber properties for pulping of spruce chips by deep eutectic solvent(Springer, 2023) Pérez, Alan; Roy, Yagnaseni; Rip, Constantijn; Kersten, Sascha R. A.; Schuur, BoeloThe chemical pulping of wood chips using deep eutectic solvents (DES-pulping) has emerged as an alternative technology to conventional pulping in the paper industry, allowing the production of pulp in combination with the recovery of lignin and sugars for valorization. A challenge in the development of this technology is the understanding of how the operating conditions influence the crucial pulp manufacturing parameters such as delignification percentage, pulp yield, and fiber quality. This work is focused on investigating the effect of operating conditions such as cooking temperature, cooking time, liquor-to-wood ratio, initial water content on DES, type of mixing, the addition of a pre-treatment step (pre-impregnation of DES into the wood chips) to cooking process, and DES composition (lactic acid:choline chloride, lactic acid:sodium chloride, and lactic acid:sodium bromide) on the cooking of wood chips by DES. A shortcut quality evaluation parameter (Q), defined as the product of the fiber length and the degree of delignification quantified the quality of the pulping process in a single value, shows values similar to a reference unbleached kraft pulp for cooking at 130 °C in a range of cooking times from 3 to 4.5 h at a L/W of 10:1 by using lactic acid:choline chloride DES. More elaborate property analysis on the fibers showed that several of the the quality-indicating properties of the fibers (coarseness, shape factor, fibril area, and crill index) are comparable with typical sulfite pulping fibers.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Effect of printing parameters on mechanical performance of material-extrusion 3D-printed PEEK specimens at the point-of-care(MDPI, 17.01.2023) Zarean, Paridokht; Zarean, Parichehr; de Wild, Michael; Thieringer, Florian M.; Sharma, Neha; Seiler, Daniel; Malgaroli, PatrickAdditive manufacturing (AM) of polyetheretherketone (PEEK) biomaterials using the material-extrusion (MEX) method has been studied for years. Because of the challenging manufacturing process, precisely controlling printing parameters is crucial. This study aimed to investigate the effects of printing parameters such as orientation and position of printing on mechanical properties. Thus, 34 samples were printed using PEEK filament and the MEX process. Samples were divided into two main groups (A,B) according to their printing orientations (A: groups 1–3) and positions on the build plate (B: groups 4–8). Mechanical tensile tests were performed to evaluate the effects of different printing orientations and positions on mechanical properties. The means of the tensile modulus in samples 3D-printed in XY (group 1), XZ (group 2), and ZX (group 3) orientations were not significantly different (p-value = 0.063). Groups 1 and 2 had smaller distributions than group 3 in the means of tensile strength. The t-test showed that the overall means of the measurements in groups 4–8 did not differ significantly (p-value = 0.315). The tensile tests indicated that printing in vertical and horizontal orientations had no significant influence on mechanical properties. There were no significant differences in mechanical strength between top/bottom printed samples in five different lateral positions. Reliability of printing with good mechanical properties could be a step forward to manufacturing patient-specific implants.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Die Chemie Pilotanlage der FHNW Muttenz(25.04.2023) Zogg, Andreas; Asprion, JonasDer Verein Miniplant 4.0 entwickelt im Process Technology Center an der FHNW neuartige Chemie-Pilotanlagen im Miniplant-Massstab. Der zentrale Scale-Down-Reaktor dient der präzisen Prozessentwicklung im Rührkessel. Insbesondere werden darin die lokalen thermischen Verhältnisse des Produktionsreaktors durch den Einsatz eines speziell designten Wärmetauschers exakt nachgebildet. Damit wird den Studenten und lokalen Unternehmen ein neuartiges Entwicklungswerkzeug zur Verfügung gestellt, welches einen schnelleren und präziseren Scale-Up von Produktionsverfahren direkt aus dem Labormassstab in den Produktionsreaktor erlaubt. Herr Prof. Dr. Andreas Zogg von der FHNW in Muttenz zeigt Ihnen den aktuellen Status der Anlage und die vielseitigen Schulungs- und Forschungsmöglichkeiten. Unterstützt wird er durch Herrn Dr. Jonas Asprion von der Firma Tool-Temp AG, welche die Kommerzialisierung der Temperierlösungen für Reaktormantel und Wärmetauscher anstrebt.06 - PräsentationPublikation New scale-up technologies for hydrogenation reactions in multipurpose pharmaceutical production plants(Schweizerische Chemische Gesellschaft, 2021) Furrer, Thierry; Müller, Benedikt; Hasler, Christoph; Berger, Bernhard; Levis, Michael Karl; Zogg, AndreasThe classical scale-up approach for hydrogenation reaction processes usually includes numerous laboratory- and pilot-scale experiments. With a novel scale-up strategy, a significant number of these experiments may be replaced by modern computational simulations in combination with scale-down experiments. With only a few laboratory-scale experiments and information about the production-scale reactor, a chemical process model is developed. This computational model can be used to simulate the production-scale process with a range of different process parameters. Those simulations are then validated by only a few experiments in an advanced scale-down reactor. The scale-down reactor has to be geometrically identical to the corresponding production-scale reactor and should show a similar mass transfer behaviour. Closest similarity in terms of heat transfer behaviour is ensured by a sophisticated 3D-printed heating/cooling finger, offering the same heat exchange area per volume and overall heat-transfer coefficient as in production-scale. The proposed scale-up strategy and the custom-designed scale-down reactor will be tested by proof of concept with model reactions. Those results will be described in a future publication. This project is an excellent example of a collaboration between academia and industry, which was funded by the Aargau Research Fund. The interest of academia is to study and understand all physical and chemical processes involved, whereas industry is interested in generating a robust and simple to use tool to improve scale-up and make reliable predictions.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation One-pot microwave synthesis of Pd modified titanium dioxide nanocrystals for 3D aerogel monoliths with efficient visible-light photocatalytic activity in a heated gas flow reactor(Royal Society of Chemistry, 01.01.2022) Kwon, Junggou; Choi, Kyoungjun; Tervoort, Elena; Niederberger, MarkusHarvesting solar energy and efficiently converting it into a chemical energy carrier like hydrogen (H2) is an important topic in photocatalysis. Here, we present a fast and simple approach for the one-pot synthesis of crystalline semiconductor nanoparticles modified with co-catalysts that can be used as nanobuilding blocks for nanoparticle-based aerogels with excellent visible-light photocatalytic activity. The microwave-assisted nonaqueous sol–gel method allows titanium dioxide (TiO2) nanoparticles to be synthesized and modified with palladium (Pd) ions and Pd metal nanoparticles in a single step. Their assembly into aerogel monoliths preserves the modified properties of the TiO2 nanobuilding blocks, resulting in morphological properties that are advantageous for the photocatalytic H2 production from methanol (CH3OH) oxidation. By controlling the amount of Pd doping and Pd nanoparticle loading, the nanoparticle-based aerogels showed significantly improved photoexcited charge generation and separation efficiency under visible light. In addition, we present a novel reactor design specifically developed for 3D aerogel monoliths that allows control of light intensity, gas flow, reactant concentration, and temperature, enabling the study of all key experimental parameters to optimize photocatalytic H2 production. The visible light absorbed by the aerogels was found to be the driving force behind the efficient photocatalytic activity. Our Pd modified TiO2 nanoparticle-based aerogels achieved H2 production rate of 117.5 mmol g−1 h−1 with good stability for 3 days under visible light thanks to the prevention of carbon monoxide (CO) poisoning. The simultaneous optimization of the material composition and the matching photoreactor form the decisive basis for getting the most out of monolithic 3D photocatalysts.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Surface water treatment by UV/H2O2 with subsequent soil aquifer treatment. Impact on micropollutants, dissolved organic matter and biological activity(Royal Society of Chemistry, 2019) Wünsch, Robin; Plattner, Julia; Cayon, David; Eugster, Fabienne; Gebhardt, Jens; Wülser, Richard; von Gunten, Urs; Wintgens, ThomasBecause organic micropollutants (MP) are frequently detected in river waters that are used as drinking water sources, combining a relatively cost-efficient natural treatment with upstream advanced oxidation processes (AOP) appears promising for their efficient abatement. Such a multi-barrier system can be integrated in drinking water production schemes to minimize risks from potentially hazardous MPs. This study investigates the impact of an UV/H2O2 AOP before soil aquifer treatment (SAT) on the abatement of selected MPs (EDTA, acesulfame, iopamidol, iomeprol, metformin, 1H-benzotriazole, iopromide), dissolved organic matter (DOM) (apparent molecular size distribution, specific UV absorbance at 254 nm – SUVA) and microbial parameters (intact cell count, cell-bound ATP). A pilot plant consisting of an AOP (0.5 m3 h−1, 4 mg L−1 H2O2, 6000 J m−2) and two parallel soil columns (filtration velocity: 1 m d−1, column height: 1 m) was continuously operated over a period of 15 months with Rhine river water pre-treated with rapid sand filtration. The investigations revealed a shift towards longer retention times of the humic substances peak in LC analysis of DOM, lower SUVA and higher biodegradability of DOM after UV/H2O2 treatment. In addition, an overall higher abatement of all investigated MPs by the combined treatment was observed (AOP with subsequent SAT) compared to either process alone. This observation could be explained by an addition of the single treatment effects. The strong primary disinfection effect of the AOP was detectable along the first meter of infiltration, but did not lead to any change in the column performance (i.e., similar abatement of dissolved organic matter).01A - Beitrag in wissenschaftlicher ZeitschriftPublikation New Scale-Up Technologies for Hydrogenation Reactions in Multipurpose Pharmaceutical Production Plants(Hochschule für Life Sciences FHNW, 2022) Zogg, Andreas; Furrer, Thierry05 - Forschungs- oder ArbeitsberichtPublikation Thermokinetic model of hydroxylamine decomposition in the catalytic oxidation of ammonia with titanium silicalite-1(Hochschule für Life Sciences FHNW, 23.10.2020) Walthert, Florian; Zogg, Andreas; Fabian Meemken LonzaHydroxylamine is a key molecule for some important chemical processes. An example is the synthesis of ε-caprolactam, which is required for the production of Nylon. Since hydroxylamine decomposes thermally, its transport and storage are problematic. It is also problematic for the synthesis of hydroxylamine from ammonia with titanium silicalite-1. The goal of this study was to investigate the exothermic decomposition reaction. The heat of the reaction was measured in multiple DSC experiments. During the decompo sition, vast quantities of gases are released. To measure the pressure rise, an explosion reactor was employed. Three reaction hypotheses have been tested. With the use of a mathematical model one hypothesis could be proven. The material in uence on the de composition reaction was examined for PEEK, stainless steel and hastelloy C22. From the DSC measurements, a descriptive model and isoconversional kinetics were obtained.11 - Studentische Arbeit