A single-molecule ferritin picking-up process was realized with the use of AFM, which was enhanced by employing controlled dendron surface chemistry. The approach enabled the placement of a single ferritin protein molecule at the very end of an AFM tip. When used for magnetic force microscopy (MFM) imaging, the tips were able to detect magnetic interactions of approximately 10 nm sized magnetic nanoparticles. The single ferritin tip also showed the characteristics of a "multifunctional" MFM probe that can sense the magnetic force from magnetic materials as well as detect the biomolecular interaction force with DNAs on the surface. The multifunctional tip enabled us not only to investigate the specific molecular interaction but also to image the magnetic interaction between the probe and the substrate, in addition to allowing the common capability of topographic imaging. Because the protein engineering of ferritin and the supporting coordination and conjugation chemistry are well-established, we envisage that it would be straightforward to extend this approach to the development of various single magnetic particle MFM probes of different compositions and sizes.

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HfO2 was deposited at 80–250 °C by plasma-enhanced atomic layer deposition (PEALD), and properties were compared with those obtained by using thermal atomic layer deposition (thermal ALD). The ALD window, i.e., the region where the growth per cycle (GPC) is constant, shifted from high temperatures (150–200 °C) to lower temperatures (80–150 °C) in PEALD. HfO2 deposited at 80 °C by PEALD showed higher density (8.1 g/cm3) than those deposited by thermal ALD (5.3 g/cm3) and a smooth surface (RMS Roughness: 0.2 nm). HfO2 deposited at a low temperature by PEALD showed decreased contaminants compared to thermal ALD deposited HfO2. Values of refractive indices and optical band gap of HfO2 deposited at 80 °C by PEALD (1.9, 5.6 eV) were higher than those obtained by using thermal ALD (1.7, 5.1 eV). Transparency of HfO2 deposited at 80 °C by PEALD on polyethylene terephthalate (PET) was high (> 84%). PET deposited above 80 °C was unable to withstand heat and showed deformation. HfO2 deposited at 80 °C by PEALD showed decreased leakage current from 1.4 × 10−2 to 2.5 × 10−5 A/cm2 and increased capacitance of approximately 21% compared to HfO2 using thermal ALD. Consequently, HfO2 deposited at a low temperature by PEALD showed improved properties compared to HfO2 deposited by thermal ALD.

With the increasing interest in hydrogen energy, the stability of hydrogen storage facilities and components is emphasized. In this study, we analyzed the effect of high-pressure hydrogen gas treatment in silica-filled EPDM composites with different silica contents. In detail, cure characteristics, crosslink density, mechanical properties, and hydrogen permeation properties were investigated. Results showed that material volume, remaining hydrogen content, and mechanical properties were changed after 96.3 MPa hydrogen gas exposure. With an increase in the silica content, the crosslink density and mechanical properties increased, but hydrogen permeability was decreased. After treatment, high-silica-content composites showed lower volume change than low-silica-content composites. The crack damage due to the decompression caused a decrease in mechanical properties, but high silica content can inhibit the reduction in mechanical properties. In particular, EPDM/silica composites with a silica content of above 60 phr exhibited excellent resistance to hydrogen gas, as no change in their physical and mechanical properties was observed.

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