Fabrication of SmCo5 Double-Layered Perpendicular Magnetic Recording Media

We fabricated SmCo₅ double-layered perpendicular magnetic recording media with high perpendicular magnetic anisotropy for realizing ultra high density recording. A double-layered medium with a Ru buffer layer introduced between a Cu/Ti intermediate layer and a Co-Zr-Nb soft magnetic underlayer exhibited high perpendicular magnetic anisotropy, whereas that without the Ru buffer layer did not. Auger electron spectroscopy revealed that the Ru buffer layer inhibited interdiffusion between the Cu/Ti intermediate layer and the Co-Zr-Nb soft magnetic underlayer. We report here for the first time the read-write characteristics of SmCo₅ double-layered perpendicular magnetic recording media. The medium noise was small in the medium with a Sm-Co layer deposited under high Ar gas pressure owing to small magnetic clusters     

Physical Retardance by Modified Gelatin

Abstract

The effect of the isoionic point of gelatin on physical ripening properties was studied by the physical retardance test using modified gelatins. Carboxylic groups were blocked by the amidation reaction and amino groups were blocked by the acylation reaction.

Physical ripening speed decreased in relation to the ratio of blocked carboxylic groups and increased when the ratio of carboxylic groups increased due to acyl substitution. However we found that the final particle size of silver halide did not depend on the isoionic point of the gelatin. It was assumed that the charge shift in the gelatin molecules affected the physical ripening speed and did not affect the final particle size.     

A localized surface plasmon resonance based immunosensor for the detection of casein in milk

In this research, a localized surface plasmon resonance (LSPR) immunosensor based on gold-capped nanoparticle substrate for detecting casein, one of the most potent allergens in milk, was developed. The fabrication of the gold-capped nanoparticle substrate involved a surface-modified silica nanoparticle layer (core) on the slide glass substrate between bottom and top gold layers (shell). The absorbance peak of the gold-capped nanoparticle substrate was observed at ～520 nm. In addition, the atomic force microscopy (AFM) images demonstrated that the nanoparticles formed a monolayer on the slide glass. After immobilizing anti-casein antibody on the surface, our device, casein immunosensor, could be applied easily for the detection of casein in the raw milk sample without a difficult pretreatment. Under the optimum conditions, the detection limit of the casein immunosensor was determined as 10 ng/mL. Our device brings several advantages to the existing LSPR-based biosensors with its easy fabrication, simple handling, low-cost, and high sensitivity.     

Combustion behavior and application of polyolefin‐based floor sheet laminated with Nylon‐6/clay nanocomposites film

Nanocomposites are potential materials that can be used to improve the flame resistance of polymers without the need for halogen‐based flame retardants. However, the nanocomposites cannot be used as the only raw material to produce final products as they are too expensive compared with low‐cost commodity plastics. Therefore, some types of polyolefin‐based floor sheet laminated with nanocomposites film were prepared for the cone calorimetric study to determine the suitable nanocomposites laminated structure for flame resistance. This study found that the polyolefin‐based floor sheet laminated with 200 µm Nylon‐6/montmorillonite nanocomposites film on the surface can reduce the HRR _max and the S significantly; other types of nanocomposites film‐laminated floor sheet were not able to reduce their flame resistance in comparison with the normal Nylon‐6 film‐laminated floor sheet. Meanwhile, based on the gas barrier performance, the higher aspect ratio of clay is assumed to contribute to the higher flame resistance of nanocomposites. Thus, the polyolefin‐based floor sheet laminated with Nylon‐6/sericite nanocomposites film on the surface was also prepared and examined in the cone calorimetric study. However, the Nylon‐6/sericite nanocomposites film surface‐laminated floor sheet did not cause a significant reduction in the HRR _max and S compared with the Nylon‐6/montmorillonite nanocomposites film surface‐laminated floor sheet. The grade determined according to the standard fire test and the mechanical properties of the Nylon‐6/montmorillonite nanocomposites film surface‐laminated floor sheet satisfied the requirements for floor sheets for Japanese railway vehicles. Copyright © 2010 John Wiley & Sons, Ltd.     

Recent advances in NiMH battery technology

Nickel-metal hydride (NiMH) is a commercially important rechargeable battery technology for both consumer and industrial applications due to design flexibility, excellent energy and power, environmental acceptability and cost. [1] From the initial product introduction in 1991 of cylindrical cells having an energy of 54 Wh kg⁻¹, today's small consumer cells have a specific energy over 100 Wh kg⁻¹. Numerous licensed manufacturers produce a myriad of NiMH products ranging from 30 mAh button cells to a wide variety of consumer cylindrical products, prismatic cells up to 250 Ah for electric buses and 6 Ah multicell modules for hybrid electric vehicles. Power has increased from under 200 to 1200 W kg⁻¹ commercially and up to 2000 W kg⁻¹ at a development level [2].     

Coaxial magnetic pulse compression system to generate fast‐rising pulsed power

A fast‐rising pulsed power generator (PPG) using a coaxial magnetic pulse compression (MPC) system has been developed. Two kinds of magnetic cores, a Co‐based amorphous metal and a nanocrystalline Fe‐based soft magnetic metal, have been used in the coaxial MPC system to evaluate losses of magnetic cores and leakage current of a saturable inductor. The PPG produced a pulsed‐high‐current of 3.7 kA with a risetime of 7 ns (20–80%) at a repetition frequency of 1000 pulses per second. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

三维分析与评价

许多重要工程的基础不得不设置在岩体斜面上，但是至今为止此类工程基础的分析理论以及设计方法并没有完全确立。基于一种考虑岩体的低抗拉强度特点的三维弹塑性有限元数值分析，对岩体斜面上设置的刚性桩基础的水平承载力进行了分析与评价，并与现场试验结果进行了比较分析。结果表明，用相对简单的三维有限元分析，可以较好地反映现场试验中所观测到的变形与破坏现象，是一种有效的评价方法。采用同样的方法，对桩到斜面项端距离以及斜面倾斜角度的变化所带来的对刚性桩基础水平承载力的影响，作了定量的分析与评价，其结果对斜面岩体上刚性桩基础的水平承载力的理论分析以及实际设计具有一定的参考价值。     

Epitaxial growth of p-sexiphenyl film on highly oriented pyrolytic graphite surface studied by scanning tunneling microscopy

The epitaxial growth of p-sexiphenyl (C₃₆H₂₆, 6P) on highly oriented pyrolytic graphite (HOPG) surface has been investigated by scanning tunneling microscopy (STM). 6P molecules prefer epitaxial growth with the long axis along the [110] direction (armchair direction) of the HOPG substrate, with the unit cell parameters b₁ = 0.67 ± 0.06 nm, b₂ = 5.97 ± 0.06 nm and angle of 88 ± 3° between them. The relation of the 6P overlayer lattice vectors with the HOPG substrate has also been deduced, i.e. the 5 × 1 supercell is in a point-on-point commensurate relation with respect to the HOPG substrate surface.     

Label-free detection of melittin binding to a membrane using electrochemical-localized surface plasmon resonance

Localized surface plasmon resonance (LSPR) and electrochemistry measurements connecting to core-shell structure nanoparticle are successfully exploited in a simultaneous detectable scheme. In this work, the surface plasmon band characterizations of this nanostructure type are initially examined by controlling the core size of the silica nanoparticle and shell thickness of the deposited gold. These results clearly show that when the shell thickness is increased, keeping the core size constant, the peak wavelength of the LSPR spectra is shifted to a shorter wavelength and the maximum of peak intensity is achieved at a particular shell thickness. On the basis of this structure, we present a membrane-based nanosensor for optically detecting the binding of peptide toxin melittin to hybrid bilayer membrane (HBM) and electrochemically assessing its membrane-disturbing properties as a function of concentrations. It will open up the way to detect functionally similar protein toxins and other membrane-targeting peptides with the intension of integrating this chip into a microfluid and expanding it into multiarray format.