Polymeric capsules often buckle, collapse or even break when being processed in the dried state into other materials under high temperature and pressure due to moderate mechanical rigidity. In the case of non-spherical capsules, to keep their precious anisotropic morphology intact under harsh conditions is even more challenging since the whole surface of such kinds of capsules does not experience the same stress or strain due to the different surface curvatures. In the current work, we reported a strategy to prepare polydopamine (PDA) capsules with an ellipsoidal shape and enhanced mechanical rigidity using polystyrene ellipsoids as the sacrificial anisotropic templates. Bio-inspired oxidation induced self-polymerization of dopamine can form conformal PDA coatings on polystyrene ellipsoids of various aspect ratios and sizes. Several strategies have been exploited to increase the thickness of the PDA shell, among which, iterating PDA coating produces ellipsoidal PDA capsules with a thick and robust shell. These ellipsoidal PDA capsules can survive carbonization at temperatures as high as 800 °C and were directly turned into N-doped carbon capsules with a well-defined ellipsoidal shape, excluding the necessity of removing the sacrificial templates after carbonation. Furthermore, the rigid PDA ellipsoidal capsules are efficient adsorbents for organic dyes in contaminated water and have impressive adsorption efficiencies as high as 200 mg g−1.

•CuO@Cu3(BTC)2 was generated using CuO as the precursor via a self-template method.•Different content of Cu3(BTC)2 in CuO@Cu3(BTC)2 was obtained by time control.•CuO@Cu3(BTC)2 showed good activity as catalyst in cumene oxidation.CuO@Cu3(BTC)2 composite (BTC=benzene-1,3,5-tricarboxylate) was synthesized via a facile self-template method using CuO as the precursor. Cu3(BTC)2 is a representative MOF (metal-organic framework), which is a class of crystalline inorganic–organic hybrid materials. By controlling synthesis time, CuO@Cu3(BTC)2 with different content of Cu3(BTC)2 was obtained. The products were characterized by X-ray diffraction (XRD), thermogravimetric (TG) analysis, transmission electron microscopy (TEM) and N2 sorption measurement. It suggested that when controlling longer synthesis time, CuO@Cu3(BTC)2 contained more Cu3(BTC)2 and showed larger surface area and total pore volume. CuO@Cu3(BTC)2 can effectively catalyze oxidation of cumene to cumene hydroperoxide (CHP) and the yield of CHP reached 18.1%, which was better than 13.6% by CuO or 8.7% by Cu3(BTC)2. When the ratio of CuO:Cu3(BTC)2 in CuO@Cu3(BTC)2 was 1:0.073 and 1:0.115, CHP yield was 18.1% and 14.2%, respectively. This study provides an approach for the oxidation of alkyl benzene using metal-oxide@MOF composite as catalyst.

The effect of magnetic field on α-amylase was studied. Under the experimental conditions, α-amylase solution was treated by 0.15 T, 0.30 T and 0.45 T static magnetic fields for a known period of time, then the activity, kinetic parameters, and the secondary conformation were investigated. The results showed that there was a considerable effect of the magnetic exposure on the α-amylase. The activity was increased by 27%, 34.1%, 37.8% compared with the control. It was also found that both kinetic parameters Km and Vm could be decreased due to the increasing magnetic field, Km decreased from 2.20×10−2 to 0.87×10−2, whereas Vm decreased from 2.0×10−3 g/min to 1.1×10−3 g/min. At the same time, there were some irregular changes in α-amylase secondary conformation.