Superparamagnetic nanoparticles coated with silica gel or alternatively steel beads are new fixed-bed materials for flow reactors that efficiently heat reaction mixtures in an inductive field under flow conditions. The scope and limitations of these novel heating materials are investigated in comparison with conventional and microwave heating. The results suggest that inductive heating can be compared to microwave heating with respect to rate acceleration. It is also demonstrated that a very large diversity of different reactions can be performed under flow conditions by using inductively heated flow reactors. These include transfer hydrogenations, heterocyclic condensations, pericyclic reactions, organometallic reactions, multicomponent reactions, reductive cyclizations, homogeneous and heterogeneous transition-metal catalysis. Silica-coated iron oxide nanoparticles are stable under many chemical conditions and the silica shell could be utilized for further functionalization with Pd nanoparticles, rendering catalytically active heatable iron oxide particles.
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http://dx.doi.org/10.1002/chem.201002291 | DOI Listing |
Water Res
January 2025
Department of Civil and Environmental Engineering, University of Florence, Via di S. Marta, 3, 50139, Firenze, Italy.
The performance of Upflow Anaerobic Sludge Blanket (UASB) bioreactors treating sulfate (SO) -rich effluents depends on multiple factors, including microbial interactions and operational conditions. The high complexity of these systems necessitates the use of mathematical modelling tools to better understand the process and predict the long-term impacts of various operational variables. In this work, a mathematical model describing the long-term operation of a sulfate-fed 2.
View Article and Find Full Text PDFOrg Process Res Dev
January 2025
School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
We report the development and optimization of a scalable flow process for metallaphotoredox (Ir/Ni) C-O coupling, a mild and efficient approach for forming alkyl-aryl ethers, a common motif in medicinal and process chemistry settings. Time-resolved infrared spectroscopy (TRIR) highlighted the amine as the major quencher of the photocatalyst triplet excited state, along with the formation of an Ir(II) species that, in the presence of the Ni cocatalyst, has its lifetime shortened, suggesting reductive quenching of Ir(III)*, followed by reoxidation facilitated by the Ni cocatalyst. TRIR and batch reaction screening was used to develop conditions transferrable to flow, and many processing benefits of performing the reaction in flow were then demonstrated using a simple to construct/operate, small-footprint FEP coil flow reactor, including short (<10 min) space times and reduced catalyst loadings (down to 0.
View Article and Find Full Text PDFHeliyon
January 2025
Faculty of Electrical Engineering, Sahand University of Technology, Tabriz, Iran.
This paper is a comprehensive reference for researchers interested in flexible AC alternating current transmission systems (FACTS) technologies. This study investigates modified UPFC models. Besides UPFC, an overview of DPFC will be presented, and the critical differences between these advanced power flow control technologies will be discussed.
View Article and Find Full Text PDFAnal Chem
January 2025
Key Laboratory of Green Chemistry & Technology of MOE, College of Chemistry, Sichuan University, Chengdu, Sichuan610064, China.
It is still challenging to perform a high-throughput digestion on limited amounts of sample prior to elemental analysis by atomic spectrometry. Herein, a photochemical reactor consisting of a quartz tube inserted into a low-pressure mercury lamp was used to fabricate a flow droplet photodigestion (FD-PD) device for the high-throughput digestion of small amounts of samples. A mixture containing 20 μL of blood sample, 20 μL of HO, and 10 μL of HNO was pumped and passed through the reactor before its online analysis by hydride generation atomic fluorescence spectrometry (HG-AFS).
View Article and Find Full Text PDFAppl Microbiol Biotechnol
January 2025
Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
A new strategy has been developed to successfully produce the active component danshensu ex vivo. For this purpose, phenylalanine dehydrogenase from Bacillus sphaericus was combined with the novel hydroxyphenylpyruvate reductase from Mentha x piperita, thereby providing an in situ cofactor regeneration throughout the conversion process. The purified enzymes were co-immobilized and subsequently employed in batch biotransformation, resulting in 60% conversion of 10 mM L-dopa within 24 h, with a catalytic amount of NAD as cofactor.
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