The crystal morphology and size of ferrierite catalysts were controlled by a suite of crystallization methods and structure-directing agents. In particular, nano-sized ferrierite could be obtained by using tetramethylammonium hydroxide and pyrrolidine as double structure-directing agents under dynamic crystallization. The catalysts were analysed by XRD, SEM, N 2 adsorption-desorption, NMR, XRF, NH 3 -TPD, Py-IR, and TGA, and the characteristics were correlated with their catalytic performance in the skeletal isomerization of n-butene. The results clearly indicated that all the catalysts have a similar crystallinity, Si/Al ratio, and total number of acid sites, while a decrease in their crystal size leads to more pore mouth acid sites. The nano-sized ferrierite showed better stability and higher activity, which were related to their crystal morphology, size, and pore mouth acid. In addition, we further confirmed that high isobutene selectivity can be produced by monomolecular reaction.

UTMD targeting intraplaque neovascularization was found to inhibit atherosclerotic plaque in a mouse model of atherosclerosis, suggesting the potential of microbubble-mediated ultrasound technology in aiding drug delivery for atherosclerosis treatment.

A series of nitrogen-doped coconut shell activated carbon catalysts were prepared by urea or melamine impregnation followed by heat treatment and used for the removal of methyl mercaptan (CH 3 SH). The physical and chemical properties of the nitrogen-doped coconut shell activated carbons were evaluated by nitrogen adsorption/desorption, scanning electron microscopy, X-ray photoelectron spectroscopy, elemental analysis, Boehm titration, and thermal analysis. The results show that CH 3 SH capacity depends on the nitrogen content. Further research indicates that pyridinic nitrogen and quaternary nitrogen are the active sites. Due to the metal-free property of the nitrogen-rich coconut shell activated carbon, the regeneration process can be easily performed and dimethyl disulfide (CH 3 SSCH 3 ) can be recovered as the main product. Our study indicates that there is a promising prospect for nitrogen-rich coconut shell activated carbon for CH 3 SH removal because of its high capacity, mild conditions, and easy regeneration.

In this study, the effective active sites of aged ferrierite(FER) were confirmed to be located in the 10‐membered ring (10‐MR) pore mouths by modification with ammonium hexafluorosilicate((NH4)2SiF6 )and long‐term experiments. Analysis of SiO2/Al2O3 ratios showed that aluminum atoms were selectively removed from the FER surface after the modification with (NH4)2SiF6. Comparison of the catalytic properties before and after modification showed that the catalytic activity of aged FER depended only on the amount of acid sites located in the 10‐MR pore mouths. Monitoring of the change in acid amount with reaction time and the difference between aged and deactivated FER showed that aged FER retained only weak acid sites, and its deactivation was caused by carbon deposition on the 10‐MR pore mouth acid sites. Therefore, the catalytic performance of FER can be improved by increasing the number of 10‐MR pore mouths.

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In this paper, the infinite-dimensional port-Hamiltonian modelling and control problem of a flexible beam actuated using ionic polymer metal composite (IPMC) actuators is investigated. The port-Hamiltonian framework is used to propose an interconnected control model of the mechanical flexible beam and the IPMC actuator. The mechanical flexible dynamic is modelled as a Timoshenko beam, and the electric dynamics of the IPMCs are considered in the model. Furthermore, a passivity-based control-strategy is used to obtain the desired configuration of the proposed interconnected system, and the closed-loop stability is analyzed using the early lumped approach. Lastly, numerical simulations and experimental results are presented to validate the proposed model and the effectiveness of the proposed control law.

Nano-hierarchical ferrierite(FER) was successfully synthesized by using pyrrolidine as sole organic structure directing(OSDA) agent under static hydrothermal conditions.SEM images showed that the morphology of the product was a loose threestage accumulation structure by nano-rod crystal grains .The influence of crystallization temperature, gel alkalinity, crystal-lization time and the amount of OSDA on synthesis of FER was investigated in detail.Moreover,FER catalytic performance in nbutene skeletal isomerizatio was investigated.The results showed that, compared with the commercial FER, the nanohierarchical FER showed better catalytic activity.