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We report a study of the effect of hydrostatic pressure on the magnetocaloric effect in a La 0.69 Ca 0.31 MnO 3 single crystal. The single crystal exhibits a much larger magnetic entropy change ͑⌬S m ͒ than the corresponding polycrystalline samples, reaching 5.2 J / kg K and 8.5 J / kg K for a magnetic field variation of 1 T and 5 T, respectively. Under hydrostatic pressure, the peak position of ⌬S m significantly moves to higher temperatures due to the shift of the magnetic phase transition, from 213.5 K under ambient pressure up to 236.5 K under a pressure of 1.1 GPa, while the maximum value of ⌬S m remains nearly the same. These exceptional results demonstrate that the magnetocaloric effect in magnetic materials with strong spin-lattice coupling can be effectively tuned by pressure.

In order to investigate the magnetic anisotropy of Fe nanowire arrays from microscopic point of view, Fe57 Mössbauer spectra were measured at various magnetic fields along and perpendicular to the nanowire axis, respectively. On the basis of the absorption intensities of the second and the fifth lines of sextet, the orientation of Fe magnetic moments can be detected. It was found that the shape anisotropy dominates the overall magnetic anisotropy in the Fe nanowires. Furthermore, the longitudinal and transverse demagnetizing fields of Fe nanowire, respectively, were deduced from the effective hyperfine field at Fe57 nuclei as a function of applied field. The chain-of-spheres model in conjunction with symmetric fanning mechanism was adopted to interpret the domain structure and the parallel coercivity of magnetic nanowire arrays.

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The ability to add synthetic channels to polymersome (polymer vesicle) membranes could lead to novel membrane composites with unique selectivity and permeability. Proton transport through two different synthetic pores, self‐assembled from either a dendritic dipeptide, (6Nf‐3,4‐3,5)12G2‐CH2‐Boc‐L‐Tyr‐L‐Ala‐OMe, or a dendritic ester, (R)‐4Bp‐3,4‐dm8G1‐COOMe, incorporated into polymersome membranes are studied. Polymersomes provide an excellent platform for studying such transport processes due to their robustness and mechanical and chemical stability compared to liposomes. It is found that the incorporated dendritic dipeptide and dendritic ester assemble into stable helical pores in the poly(ethylene oxide)‐polybutadiene (PEO‐PBD) polymersomes but not in the poly(2‐methyloxazoline)‐poly(dimethylsiloxane)‐poly(2‐methyl oxazoline) (PMOX‐PDMS‐PMOX) polymersomes. The incorporation is confirmed by circular dichroism (CD), changes in purely synthetic mechanical strength (e.g., areal expansion modulus) as assessed by micropipette aspiration, and cryo‐TEM. In addition to the structural analyses, a transport measurement shows the incorporated dendritic helical pores allow facile transport of protons across the polymersome membranes after up to one month of storage. This integration of synthetic porous channels with polymersome substrates could provide a valuable tool for studying active transport processes in a composite membrane. These composites will ultimately expand the family of biologically inspired porous‐membrane mimics.