Nonthermal and selective crystal bridging of ZnO grains by irradiation with electron beam as nonequilibrium reaction field.

Ceramic particles, such as titanium oxide and indium tin oxide, are expected to be used as electric or catalytic materials for various applications. In this work, we progressed to employ the irradiation with an electron beam as the nonequilibrium reaction field for ceramic composition, and we successfully obtained the basic technology for a ceramic thin-film fabrication using a field emission (FE) electron beam with low energy resolution having a half width under 100 meV that had a homogeneous planar electron emission as the nonequilibrium reaction field. In particular, ZnO particles synthesized by electron beam irradiation show selective crystal bridging along the c-axis during FE electron beam irradiation, which is important for synthesizing poly-ZnO crystals without a heating process, because the energy fluctuations of FE electron beams are small and affect the directionality of ZnO crystal growth along the c-axis.

Uneven damage on head and liner contact surfaces of a retrieved Co-Cr-based metal-on-metal hip joint bearing: An important reason for the high failure rate.

Detailed metallurgical investigations have been performed on a used Co-Cr-based metal-on-metal (MoM) hip joint bearing containing a type of liner that is commonly used in such joints. The damage on the metal-liner sliding surface was considerably more severe than that on the metal head counterpart, in terms of wear-scar density and width and microcrack frequency. Cross-sectional transmission electron microscopy revealed that a thick (>3 μm) nanocrystalline layer formed on the sliding surface of the head, whereas the liner had coarse carbides embedded in it and nanocrystals were formed in a very limited region no deeper than 1 μm.

Localization Effect on Pt-Loaded Ce0.5Zr0.5O2 Nanoparticles Inserted Into Mesoporous SBA-16 by Hydrothermal Processing.

We succeeded to use hydrothermal treatment to insert prefabricated Pt-loaded Ce0.5Zr0.5O2 (PtCZ) nanoparticles into the mesopores of the SBA-16 mesoporous silica without disordering of the mesoporous structure.

Numerical analysis of electron emission site distribution of carbon nanofibers for field emission properties.

To obtain optimal field emission (FE) properties, it is important to evaluate FE parameters including the electron emission site α and the field enhancement factor β. However, it is difficult to evaluate α quantitatively because the emitting electrons cannot be observed directly. The authors have aimed to analyze this site using an original architecture with a computation system tool based on the surface charge method, and a three-dimensional model has been employed to calculate FE properties with high accuracy.

Semiconducting cross-linked polymer nanowires prepared by high-energy single-particle track reactions.

High-energy charged particle irradiation of cross-linking polymers gives nanowires formed by cross-linking reactions along the ion track trajectories. Here, the direct formation of nanowires consisting of a conjugated polymer by single-particle nanofabrication technique (SPNT) is investigated. Poly(9,9'-di-n-octylfluorene) (PFO), regioregular poly(3-hexylthiophene) (rrP3HT), and poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) underwent an efficient cross-linking reaction upon irradiation, resulting in the formation of 1-dimensional nanostructures with high and desired aspect ratio reaching up to ∼200.

Crystal growth of thiol-stabilized gold nanoparticles by heat-induced coalescence.

A monolayer of dodecanethiol-stabilized gold nanoparticles changed into two-dimensional and three-dimensional self-organized structures by annealing at 323 K. Subsequent crystal growth of gold nanoparticles occurred. Thiol molecules, although chemisorbed, form relatively unstable bonds with the gold surface; a few thiols desorbed from the surface and oxidized to disulfides at 323 K, because the interaction energy between thiol macromolecules is larger than that between a thiol and a nanoparticle.

Effect of the wavelength of infrared heaters on the inactivation of bacterial spores at various water activities.

Bacterial spores (Bacillus subtilis subsp. subtilis NBRC 16183) inoculated onto a stainless steel Petri dish and treated at nine levels of water activity (a(w)) for 2 days were inactivated by infrared radiation heating (IRH) using three kinds of infrared heaters with different radiation spectra. The peak wavelengths used were 950, 1,100 and 1,150 nm.