In the present study,a plasma-electrochemical method was demonstrated for the synthesis of europium doped ceria ***(NO3)3· 6H2O and Eu(NO3)3·5H2O were used as the starting materials and being dissolved in th...
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In the present study,a plasma-electrochemical method was demonstrated for the synthesis of europium doped ceria ***(NO3)3· 6H2O and Eu(NO3)3·5H2O were used as the starting materials and being dissolved in the distilled water as the electrolyte *** plasma-liquid interaction process was in-situ investigated by an optical emission spectroscopy,and the obtained products were characterized by complementary analytical *** showed that crystalline cubic CeO2:Eu3+ nanoparticles were successfully obtained,with a particle size in the range from 30 to 60 *** crystal structure didn't change during the calcination at a temperature from 400℃ to 1000℃,with the average erystallite size being estimated to be 52 nm at 1000℃.Eu3+ ions were shown to be effectively and uniformly doped into the CeO2 *** a result,the obtained nanophosphors emit apparent red color under the UV irradiation,which can be easily observed by naked *** photoluminescence spectrum further proves the downshift behavior of the obtained products,where characteristic 5Do → 7F1,2,3 transitions of Eu3+ ions had been *** to the simple,flexible and environmental friendly process,this plasma-electrochemical method should have great potential for the synthesis of a series of nanophosphors,especially for bio-application purpose.
A mild and selective C(sp 3 )−H aerobic oxidation enabled by decatungstate photocatalysis has been developed. The reaction can be significantly improved in a microflow reactor enabling the safe use of oxygen and enhan...
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A mild and selective C(sp 3 )−H aerobic oxidation enabled by decatungstate photocatalysis has been developed. The reaction can be significantly improved in a microflow reactor enabling the safe use of oxygen and enhanced irradiation of the reaction mixture. Our method allows for the oxidation of both activated and unactivated C−H bonds (30 examples). The ability to selectively oxidize natural scaffolds, such as (−)‐ambroxide, pregnenolone acetate, (+)‐sclareolide, and artemisinin, exemplifies the utility of this new method.
Styrenes represent a challenging class of substrates for current radical trifluoromethylation and hydrotrifluoromethylation methods due to a myriad of potential side reactions. Herein, we describe the development of m...
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Styrenes represent a challenging class of substrates for current radical trifluoromethylation and hydrotrifluoromethylation methods due to a myriad of potential side reactions. Herein, we describe the development of mild, selective and broadly applicable photocatalytic trifluoromethylation and hydrotrifluoromethylation protocols for these challenging substrates. The methods use fac‐Ir(ppy) 3 , visible light and inexpensive CF 3 I and can be applied to a diverse set of vinylarene substrates. The use of continuous‐flow photochemical reaction conditions allowed to reduce the reaction time and increase the reaction selectivity.
microprocesstechnology has given strong push to continuous chemical manufacture via facilitating heat and mass transfer(transport intensification). The next big step is to develop a tailored processchemistry in flo...
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microprocesstechnology has given strong push to continuous chemical manufacture via facilitating heat and mass transfer(transport intensification). The next big step is to develop a tailored processchemistry in flow under highly intensified conditions – which is one essence among the developing field of flowchemistry. This has been coined Novel process Windows and has two research pillars, the exploration of unusual and typically harsh process conditions(chemical intensification) and, in a more holistic picture, a completely new and often simpler process design(processdesign intensification). Reactivity is boosted via high-T, high-p, high-c(solvent-free;alternative solvent) concepts and more. Recently, biotechnology and flowchemistry merged into enzymatic micro-flow reactors. Enzymes are commonly immobilized on porous beads filled into a tube – a micro-flow packed bed reactor. The making of highvalue building blocks for APIs is demonstrated by the formation of alpha amino alcohols with Threonine Aldolase.A transesterification with Lipase underlines how productivity, sufficient at least for pharma level, may be achieved and what bottlenecks are still to overcome. Starting from such new reaction designs, new process designs in flow are developed, with major consequences on CAPEX/OPEX costs, sustainability, and energy consumption(heat integration,pinch analysis). On top of that, the embedment of flowprocessing into modern compact modular chemical production platforms(‘Future Factories';container) such as Evonik's Evotrainer is discussed. Such modern chemical manufacturing allows a faster return on invest by reducing time-to-market(‘windows of opportunity') especially for high-value chemicals and in volatile markets. First evidence is given by cash-flow analysis, determining the net-present value.
The use of solar light to promote chemical reactions holds significant potential with regard to sustainable energy solutions. While the number of visible light‐induced transformations has increased significantly, the...
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The use of solar light to promote chemical reactions holds significant potential with regard to sustainable energy solutions. While the number of visible light‐induced transformations has increased significantly, the use of abundant solar light has been extremely limited. We report a leaf‐inspired photomicroreactor that constitutes a merger between luminescent solar concentrators (LSCs) and flow photochemistry to enable green and efficient reactions powered by solar irradiation. This device based on fluorescent dye‐doped polydimethylsiloxane collects sunlight, focuses the energy to a narrow wavelength region, and then transports that energy to embedded microchannels where the flowing reactants are converted.
Innovative ways of providing novel sustainable solutions to reduce the emissions and consumption of exhaustible resources is called for. Production of liquid fuels from bioresources satisfies this call and it is aimed...
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