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Novel supported task-specific ionic liquids have been developed for the first time via the ionic-pair coupling of imidazolium cation of the modified polystyrene support with L-proline. The materials have shown an efficient metal scavenging ability (e.g., CuI, Pd(OAc)2, Pd0, and IrCl3) without the aid of a nonimmobilized ionic liquid, which relies on the highly synergistic effect of the coordination with the nitrogen atom and the COO- group of the L-proline moiety, electrostatic forces, and steric protection. The resulting metal-soaked supported ionic liquids can be used as efficient heterogeneous catalysts. These materials have been investigated in the CuI-catalyzed N-arylation of nitrogen-containing heterocycles and exhibit much higher catalytic activity and a more extensive structural range of aryl and heteroaryl halides than those exhibited by free L-proline in combination with CuI both in the ionic liquid ([BMIM][BF4]) and in the corresponding homogeneous reaction conditions. The CuI-soaked catalyst 4a-2 can be recycled for nine runs at least without any considerable loss of activity. To the best of our knowledge, our catalytic process is among the most efficient approaches to the N-arylation of imidazoles with aryl halides so far reported. Furthermore, the Pd-soaked material 4a-2 also shows higher catalytic activity in the solvent-free hydrogenation of styrene to ethylbenzene. This new concept is generally applicable and may easily be extended to other supported task-specific ionic liquids.

In this work, NiCo 2 O 4 @NiCo 2 S 4 nanocomposite with a hierarchical structure is prepared by a multistep process. First, NiCo 2 O 4 nanowires array on Ni foam is prepared by a hydrothermal and a subsequent calcination process. Then, the NiCo 2 O 4 nanowires array is converted to NiCo 2 O 4 @NiCo 2 S 4 nanocomposite through a vapor-phase hydrothermal process. The NiCo 2 O 4 @NiCo 2 S 4 /Ni foam electrode exhibits a specific capacitance of 1872 F g –1 at 1 A g –1 , a capacitance retention of 70.5% at 10 A g –1 , and a retention ratio of 65% after 4000 charge–discharge cycles. The capacitance of NiCo 2 O 4 @NiCo 2 S 4 nanocomposite is much higher than that of the NiCo 2 O 4 nanowires array. The excellent electrochemical capacitive performances of the NiCo 2 O 4 @NiCo 2 S 4 nanocomposite can be attributed to the hierarchical nanostructure, which can provide large surface areas and short diffusion pathways for electrons and ions. By using the NiCo 2 O 4 @NiCo 2 S 4 /Ni foam as the positive electrode and activated carbon/Ni foam as the negative electrode, a hybrid supercapacitor device is fabricated. The device achieves an energy density of 35.6 W h kg –1 and a power density of 1.5 kW kg –1 at 2 A g –1 .

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The use of illegal fish drugs, such as malachite green (MG) in aquaculture has raised growing concerns over the safety of aquatic food products, and sensitive and rapid methods for detection of these drugs in fish muscle are much needed. Simplified extraction methods coupled with surface‐enhanced Raman spectroscopy were used for analysis of MG and its metabolite leucomalachite green (LMG) in tilapia fillets containing 0–50 ng g−1 LMG or MG. Principal component analysis and partial least squares (PLS) regression were used for spectral data analyses. High sensitivity (MG or LMG could be detected at 1–2 ng g−1 levels) and PLS models with good predictability [root mean square error of validation (RMSEV) = 1.97–2.21 ng g−1, R2 = 0.984–0.988] were possible with suitable sample extraction methods. The simplest extraction method developed provided an RMSEV of 9.32 ng g−1 and R2 of 0.788, and although this was not ideal, detection of MG and LMG at 5 ng g−1 level with this method could reduce sample throughput time and provide for faster detection of LMG and MG. Copyright © 2012 John Wiley & Sons, Ltd.