The lattice disordering transition (LDT) and the domain dissolution transition (DDT) of a highly asymmetric polystyrene-block-poly(ethylene-co-but-1-ene)-block-polystyrene (SEBS-8) triblock copolymer with a volume fraction of polystyrene (PS) block of 0.084 have been investigated by small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), and rheology. The PS spheres formed in the SEBS-8 sample exhibited a body-centered cubic (bcc) lattice at lower temperatures and underwent disordering in the bcc lattice (so-called LDT) at ∼150 °C. Above this temperature (T LDT), spheres in liquidlike short-range order (LSO) with relatively thin interface between the PS domain and the poly(ethylene-co-but-1-ene) (PEB) matrix were detected up to ∼210 °C, above which the spherical domains started to dissolve into the PEB matrix. Finally, the spherical domains were completely dissolved into a homogeneous state at ∼232 °C. The starting and the final dissolution temperatures are referred to as the T DDT and the order-to-disorder transition temperature (T ODT). The LDT was verified by the SAXS results that the higher order diffraction peaks from the bcc lattice disappeared above the T LDT, while particle scattering of spheres due to the intraparticle interference as well as the interparticle interference of spheres in LSO was clearly observed between the T LDT and the T DDT. The spheres in LSO were further elucidated by rheology and TEM observation. It was found that a precipitous decrease in storage modulus (G‘) and a dramatic change in the Bragg spacing occurred at the same temperature of the T LDT. It was also observed that the slope in the plots of G‘ versus frequency (ω) and that in the plots of loss modulus (G‘ ‘) versus ω in the terminal region were two and one, respectively, at temperatures above the T LDT. This is attributed to the fact that because of the absence of the bcc lattice in long-range order, spheres in LSO do not contribute significantly to the shear moduli in the terminal region. Therefore, even if the terminal behavior observed generally for a homogeneous mixture (namely the slopes in the plots of G‘ versus ω and G‘ ‘ versus ω are two and one) is exhibited at a temperature, this temperature is not necessarily above the T ODT. The characteristic domain spacing in LSO did not change much with temperature, but it increased between the T DDT and the T ODT due to the dissolution of spheres.

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Carbon nanotubes ͑CNTs͒ were grown on Si substrates by rf CH 4 plasma-enhanced chemical vapor deposition in a pressure range of 1 -10 Torr, and then characterized by scanning electron microscopy. At 1 Torr, the CNTs continued growing up to 60 min, while their height at 4 Torr had leveled off at 20 min. CNTs hardly grew at 10 Torr and amorphous carbon was deposited instead. CH 4 plasma was simulated using a one-dimensional fluid model to evaluate the production and transport of radicals, ions, and nonradical neutrals. The amount of simulated carbon supplied to the electrode surface via the flux of radicals and ions such as CH 3 , C 2 H 5 , and C 2 H 5 + was consistent with estimations from experimental results.

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We provide direct evidence of plasma-induced pore formation in a cell membrane model system. We irradiated plasma on the basis of the dielectric barrier discharge onto a supported lipid bilayer (SLB). Observation with a fluorescence microscope and atomic force microscope revealed the formation of pores on the order of 10 nm–1 µm in size. Capturing these micropores in a fluid lipid membrane is a significant advantage of the SLB system, and quantitative analysis of the pores was performed. Stimulation with equilibrium chemicals (HNO3 and H2O2) indicated that other transient active species play critical roles during the poration in the SLB.

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Double-walled carbon nanotubes (DWCNTs) were synthesized by chemical vapour deposition using Fe-Mo catalyst supported on magnesium oxide particles. A mixture of gases of methane and hydrogen was used for the growth. The effect of gas pressure, ratio of methane to hydrogen, and growth temperature on the structure, purity, and yield of DWCNTs has been studied in detail. Transmission electron microscope studies revealed that the growth temperature is the crucial factor determining the size of the catalyst particles. Scanning electron microscope studies were also carried out to provide information on the purity and diameter of DWCNTs synthesized under various conditions.

The mechanism of Sn surface segregation during the epitaxial growth of GeSn on Si (001) substrates was investigated by Auger electron spectroscopy and energy dispersive X-ray spectroscopy. Sn surface segregation depends on the growth temperature and Sn content of GeSn layers. During Sn surface segregation, Sn-rich nanoparticles form and move on the surface during the deposition, which results in a rough surface owing to facet formation. The Sn-rich nanoparticles moving on the surface during the deposition absorb Sn from the periphery and yield a lower Sn content, not on the surface but within the layer, because the Sn surface segregation and the GeSn deposition occur simultaneously. Sn surface segregation can occur at a lower temperature during the deposition compared with that during postannealing. This suggests that the Sn surface segregation during the deposition is strongly promoted by the migration of deposited Ge and Sn adatoms on the surface originating from the thermal effect of substrate temperature, which also suggests that limiting the migration of deposited Ge and Sn adatoms can reduce the Sn surface segregation and improve the crystallinity of GeSn layers.