| 1. |
- Cheng, Jie, et al.
(författare)
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Guanidimidazole-quanternized and cross-linked alkaline polymer electrolyte membrane for fuel cell application
- 2016
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Ingår i: Journal of Membrane Science. - : Elsevier BV. - 0376-7388 .- 1873-3123. ; 501, s. 100-108
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Tidskriftsartikel (refereegranskat)abstract
- A modified imidazole, namely guanidimidazole (GIm) was designed and synthesized as a novel quaternizing- and cross-linking agent for alkaline polymer electrolyte membrane fabrication. The resulting membrane was more alkali tolerant and swelling resistant than that quaternized purely by 1-methylimidazole owing to the enhanced resonance and cross-linking ability of GIm, the former confirmed by a LUMO (lowest unoccupied molecular orbital) energy calculation. The membrane also showed good ionic conductivity, mechanical strength and thermal stability. A H2/O2 fuel cell using the synthesized membrane showed a peak power density of 39 mW cm−2 at 50 °C. This work preliminarily demonstrates the beneficial effect of imidazole modification by both experimental and computational investigation; it provides a new cation design strategy that may potentially achieve simultaneous improvement of alkali-stability and swelling resistance of alkaline electrolyte membranes.
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| 2. |
- Li, Qianjin, et al.
(författare)
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A paradigm shift design of functional monomers for developing molecularly imprinted polymers
- 2018
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 350, s. 217-224
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Tidskriftsartikel (refereegranskat)abstract
- Functional monomers play a key role in preparing molecularly imprinted polymers (MIPs) by forming complex with templates to create recognition sites in the polymers. In this paper, a new strategy was proposed to design functional monomers for efficient MIPs synthesis. This strategy dated from the investigations on previously developed MIPs. In propranolol imprinting process, methacrylic acid has always been used as a functional monomer, due to the efficient hydrogen bonding interactions between the carboxyl group in methacrylic acid and the 2-hydroxylethylamine group in propranolol. Given this, we assumed that a functional monomer having a 2-hydroxylethylamine moiety may be used to imprint carboxylic acid molecules e.g. naproxen. To demonstrate this idea, a new monomer 2-hydroxy-3-(isopropylamino)propyl methacrylate (HIMA) was designed. Computation results, by means of density functional theory method, revealed that HIMA could form a stable complex with naproxen through hydrogen bonding interactions with the carboxylic acid group. HIMA was then used to synthesize naproxen-imprinted polymers via precipitation polymerization. Binding experiments showed that all the MIPs could selectively recognize naproxen, confirming the feasibility of our paradigm shift in functional monomer design. The new functional monomer HIMA is a promising ligand that may be used to imprint other molecules having carboxylic acid or phosphoric acid groups. The paradigm shift in this study thereby opens a new avenue to design functional monomers for developing MIPs.
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| 3. |
- Li, Qianjin, et al.
(författare)
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Synthesis of fluorescent molecularly imprinted nanoparticles for turn-on fluorescence assay using one-pot synthetic method and a preliminary microfluidic approach
- 2018
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Ingår i: Polymer. - : Elsevier BV. - 0032-3861. ; 138, s. 352-358
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Tidskriftsartikel (refereegranskat)abstract
- Fluorescent molecularly imprinted polymers (MIPs) have received considerable attention for their promising applications in sensing, imaging and diagnostics. Different synthetic methods have been reported to prepare fluorescent MIPs. Here, one-pot polymerization method was developed to synthesize fluorescent MIP nanoparticles (NPs) bearing a suitable fluorescent label as the fluorescence acceptor. The MIP NPs can emit strong fluorescence based on fluorescence resonance energy transfer (FRET) when they bind to analytes acting as the fluorescence donor. The one-pot synthetic method is straightforward, less time-consuming and easy to optimize the loading of fluorescence acceptor. Additionally, a preliminary microfluidic reactor was designed for preparing such fluorescent MIP NPs with more uniform size in a continuous process for the first time. The fluorescent MIP NPs can be used for selective detection of the analytical target in a FRET-based turn-on fluorescence assay which is easy to carry out with no tedious separation steps.
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