Œ¤‹†•ñ���@-�@33Šª�@(2013”N)

‘��à - Review

33-1

—U“d‰j“®‚É‚æ‚é”÷—±Žq‘€�ì‚ð‰ž—p‚µ‚½�v‘¬‚ȖƉu‘ª’è
Rapid immunosensing based on dielectrophoretic manipulation of particles

ˆÀ�ì ’q”V
T. Yasukawa

˜_•¶ - Original

33-2

ZrNi-H Œn‚ÌŽ¥‹C“Á�«
Magnetic properties of ZrNi-H systems

�ÔŠÛ ŒåŽm�A‰ªú± Œ\—S�AŒ´ �³Œ›�A”g‘½–ì —YŽ¡�A�¼ŽR �­•v
S. Akamaru, K. Okazaki, M. Hara, Y. Hatano, M. Matsuyama

33-3

�V‚µ‚­ŠJ”­‚µ‚½”÷—±Žq•\–Ê�C�ü—p‘½ŠpƒoƒŒƒ‹ƒvƒ‰ƒYƒ}‰»Šw�ö’…–@‚ÌŠT—v
Outline of the Polygonal Barrel-Plasma Chemical Vapor Deposition Method Newly Developed for Particle Surface Modification

–{‘½ —S“ñ�Aˆä�ã Œõ�_�Aˆ¢•” �F”V
Y. Honda, M. Inoue, T. Abe

33-4

‘½ŠpƒoƒŒƒ‹ƒXƒpƒbƒ^ƒŠƒ“ƒO–@‚ð—p‚¢‚Ä’²�»‚µ‚½ŒÅ‘Ì�‚•ªŽqŒ`”R—¿“d’r—p Pt/TiN/C ƒJƒ\�[ƒh�G”}‚Ì“d‹C‰»Šw“I—ò‰»‘Ï�«
Electrochemical Degradation Resistance of Pt/TiN/C Cathode Catalysts for Polymer Electrolyte Fuel Cells prepared using the Polygonal Barrel-Sputtering Method

‰œ“‡ �N�³�Aˆä�ã Œõ�_�Aˆ¢•” �F”V
Y. Okushima, M. Inoue, T. Abe

33-5

‹ß�ÔŠO•ªŒõ‚Ì‚½‚ß‚Ì“ñ�dŠÇƒZƒ‹ƒVƒXƒeƒ€‚ÌŠJ”­
Development of a double-walled cell system for near-infrared spectroscopy

�¬—Ñ ‚©‚¨‚è�Aê  ‘׊ì�A ŽR–{ ‘ñ–ç�AŒ´ �³Œ›�A”g‘½–ì —YŽ¡
K. Kobayashi, H. Maki, T. Yamamoto, M. Hara, Y. Hatano

ƒm�[ƒg - Note

33-6

CECE�G”}—p‘a�…�«ƒVƒŠƒJƒr�[ƒY‚Ì�×�E�\‘¢‹y‚Ñ�…�ö‹C‹z’…“Á�«
Porosity and water vapor sorption property of new hydrophobic silica beads for CECE catalyst support

“cŒû –¾�A�™ŽR ‹M•F�A�X“c —m•½�A“c’† �«—T�AŒÃ“¡ Œ’Ži�A�@‘œ Œ’ŽO
A. Taguchi, T. Sugiyama, Y. Morita, M. Tanaka, K. Kotoh,K. Munakata

‹Z�p•ñ�� - Technical report

33-7

�Ï•ª–@‚ð—p‚¢‚½³⁵S ‚̉t‘̃Vƒ“ƒ`ƒŒ�[ƒVƒ‡ƒ“ƒJƒEƒ“ƒ^‚É‚æ‚é•úŽË”\‘ª’è
Radioactivity measurement of ³⁵S by liquid scintillation counter with modified integral counting method

Œ´ �³Œ›�A•ÐŽR ’m���A’†ŽR �«�l�A�¼ŽR �­•v�AœA�ã �´ˆê�A�‚“c ‰pŽ¡�A‘Ü•z �¹Š²�A’šŽq “NŽ¡
M. Hara, C. Kataya, M. Nakayama, M. Matsuyama, K. Hirokami, E. Takada, M. Tafu, T. Choji

---

Œ¤‹†•ñ��33 - 1
‘��à - Review

A rapid immunosensing method for measuring two tumor markers, alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA), based on particle manipulation by negative dielectrophoresis (n-DEP) was developed. When microparticles modified with different antibodies were subjected to n-DEP manipulation by the application of an AC voltage, they accumulated in particular positions in poly(dimethylsiloxane) (PDMS) fluidic channels modified with corresponding antibodies within 1 min. The presence of a specific antigen, AFP or CEA, allowed the irreversible capture of microparticles via the formation of immuno-complexes. Uncaptured microparticles redispersed after the AC voltage was switched off. The fluorescent intensity from the irreversibly captured microparticles allowed us to determine the concentration of AFP and CEA in the sample. The range for both AFP and CEA assays was 0.1-100 ng/mL, which was sufficient to cover the concentration required for medical diagnoses. Our system measured the concentrations of AFP and CEA simultaneously in a single device with two channels modified for different antibodies. Since n-DEP was used for the rapid manipulation of the microparticles toward the PDMS surface, the time required for the assay was substantially short: 1 min for forcing and 5 min for redispersion of microparticles and sensing.

We estimate the amount of hydrogen isotope gas stored in getter materials without using a desorption process and by measuring the magnetic susceptibility of ZrNi-H systems. The magnetic susceptibility of ZrNiH x increased with an increase in the hydrogen content, x, reaching a maximum value at x ≅ 0.5. As x > 0.5, the magnetic susceptibility began to decrease and reached a minimum value at x= 2.7. The behavior of magnetic susceptibility could be qualitatively modeled using the molar fractions of the ZrNi, monohydride, and trihydride phases observed using X-ray diffraction analysis.

  This report describes the outline of the �gpolygonal barrel-plasma chemical vapor deposition (CVD) method�h and its units in detail. This method is embodied as a new particle surface modification system consisting of 5 parts: 1) a gas-supply unit, 2) a vacuum chamber unit (including gas shower and barrel electrodes), 3) a radio frequency (RF) power supply unit (including matching box), 4) a vacuum pumps, and 5) a control unit. In this method, a hexagonal barrel containing particles is rotated or oscillated during plasma CVD, leading to the efficient and uniform surface modification of individual particles with various materials, especially carbon and metal oxides. In addition, the film thicknesses of the deposited materials can be controlled very easily by changing the RF power and treatment time. Thus, the polygonal barrel-plasma CVD method allows controllable surface modification of particles and is useful for research and development of functionalized particles.

  Electrochemical degradation resistance of carbon-supported Pt and TiN (Pt/TiN/C) cathode catalysts for polymer electrolyte fuel cells prepared using the polygonal barrel-sputtering method was investigated. The characterization of the prepared carbon-supported TiN (TiN/C) samples showed that TiN nanoparticles were uniformly deposited on the surfaces of the carbon particles. Subsequently, Pt/TiN/C catalysts were prepared by sputtering Pt on the TiN/C samples. The change in electrochemical surface areas (ESAs) of the obtained samples was evaluated by successive potential cycling. As compared with the carbon-supported Pt catalyst, the Pt/TiN/C catalyst with the amount of TiN deposited of 10 wt.% showed smaller ESA reduction after 100th potential cycling. The effects of TiN on the ESA reduction became greater by increasing the amount of deposited TiN from 10 to 24 wt.%, although the ESA absolute values decreased. These results demonstrate that TiN deposition is useful to prevent ESAs from reduction and improve the durability of PEFCs.

  Near-infrared spectroscopy has potential as a new suitable tool to detect tritiated water (HTO, T₂O). We previously carried out the initial study with a single-walled cell system and got some spectra of tritiated water vapor. Because of the radioactive nature of tritium, tritiated water was decomposed into tritium gas and oxygen by radiochemical reactions, and there was a need for a reoxidizing system and other updates to improve tritium recycling and safety issues. Therefore, we developed a new double-walled cell system and tested its basic performance. The performance of the cell was found to be appropriate for the prolonged measurement of the spectra of tritiated water vapor.

  The porosity and water vapor sorption property of commercially available hydrophobic SiO₂beads were investigated. The hydrophobic SiO₂ beads, the surface of which has been modified by trimethylsilyl functional groups, with a surface area of 70.7 m²/g, a mesopore diameter of about 36 nm and a mesopore volume of about 0.91 cm3/g showed lower water vapor sorption property as compared to the unmodified SiO₂ beads; the amount of monolayer water adsorbed were estimated to be 2.94�~10^-3 and 5.12�~10^-3 _{g(H2O)/g(adsorbent)} for hydrophobic and unmodified SiO₂ beads, respectively. The evaluation of the heat of water vapor sorption suggests that the suppression of water cluster formation by trimethylsilyl groups is attributed to the hydrophobic property.

  To confirm the applicability of the modified integral counting method for the radioactivity measurements of low energy beta emitters, the radioactivity measurements of ³⁵S and ¹⁴C were carried out using a liquid scintillation counter. The disintegration rates of ³⁵S and ¹⁴C were evaluated from the liquid scintillation spectra by the modified integral counting method. The disintegration rates thus obtained sufficiently supported the applicability of this method to the radioactivity measurement by liquid scintillation counting without using quenched standards. Discussion was also given concerning the measurement procedures involving the modified integral counting method.