Fabrication and characterization of high performance cathode supported small-scale SOFC for intermediate temperature operation

A high performance small-scale solid oxide fuel cell supported by a microtubular cathode was successfully developed via the extrusion of a (La_0.8Sr_0.2)_0.97MnO₃ cathode support and subsequent surface coating with a (La_0.8Sr_0.2)_0.97MnO₃–Ce_0.9Gd_0.1O_1.95 activation layer followed by Sc₂O₃-doped ZrO₂ electrolyte and NiO–Ce_0.9Gd_0.1O_1.95 anode slurries. The cell was electrochemically evaluated in a humidified hydrogen (3% H₂O) atmosphere, and exhibited a stable open circuit voltage above 1.05 V in the temperature range from 550 to 750 °C. Maximum power densities of 46.5, 163.2 and 452.8 mW cm⁻² were generated at 550, 650 and 750 °C, respectively. The results indicate the realization of a stable and high performance cathode-supported micro SOFC.     

Nuclease tolerant FRET probe based on DNA-quantum dot conjugation.

We have developed a fluorescence resonance energy transfer (FRET) probe based on the conjugation of a quantum dot (QD) with dye (YOYO-3) intercalated DNA. The FRET-inducing electrostatic coupling of DNA and the QD made structural changes to the QD-DNA conjugates, which significantly prevented an enzymatic reaction between the DNA and a conventional restriction endonuclease (EcoRI).     

An organic electroluminescent device with a molecularly doped polymer hole transport layer

Electroluminescent(EL) devices have been fabricated using four different polymers with different glass transition temperatures (T_g) dispersed with N,N′-bis-(3-methylphenyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (TPD) as a hole transport layer and tris(8-hydroxyquinoline) aluminum (Alq₃) as an emitting layer. It was found that the higher the T_g of the polymer, the longer the lifetime of the device. From observations of TPD-doped polymer films with optical microscope and atomic force microscope, dispersing TPD in the polymers was found to suppress the crystallization that causes the roughness of the film surface. It was also observed that the higher the T_g of the host polymers, the more difficult TPD crystallization was. The property of the EL device with polyethersulfone (PES) dispersed with TPD was also investigated. The lifetime of EL device with the TPD doped PES film was improved more than five times at a current density below 10 mA/cm² compared with the device with a conventional TPD hole transport layer. © 1997 John Wiley & Sons, Ltd.     

Synthesis and thermal properties of cellulose-based polycaprolactones

Cellulose-based polycaprolactone (CAPCL) sheets were prepared from cellulose acetate (CA) and ϵ-caprolactone (CL). Thermal properties of the obtained CAPCL's were studied by differential scanning calorimetry (DSC), thermogravimetry (TG) and TG-Fourier transform infrared spectrometry (TG-FTIR). The glass transition temperatures (T_g 's) of CAPCL decreased with increasing CL/OH ratio, until CL/OH ratio reached 15 and then increased above that ratio. Melting of CAPCL was observed when CL/OH ratio was over 10. The thermal degradation temperatures (T_d 's) of CAPCL increased from ca. 350 °C to 390 °C with increasing CL/OH ratio. The results obtained by TG-FTIR analysis of CAPCL showed that gases with OH, CH, C=O, C-O-C groups evolved by thermal degradation.     

Microchip electrophoretic protein separation using electroosmotic flow induced by dynamic sodium dodecyl sulfate-coating of uncoated plastic chips

Separation of sodium dodecyl sulfate (SDS)-protein complexes is difficult on plastic microchips due to protein adsorption onto the wall. In this paper, we elucidated the reasons for the difficulties in separating SDS-protein complexes on plastic microchips, and we then demonstrated an effective method for separating proteins using polymethyl methacrylate (PMMA) microchips. Separation difficulties were found to be dependent on adsorption of SDS onto the hydrophobic surface of the channel, by which cathodic electroosmotic flow (EOF; reversed flow) was generated. Our developed method effectively utilized the reversed flow from this cathodic EOF as a driving force for sample proteins using permanently uncoated but dynamic SDS-coated PMMA microchips. High-speed (6 s) separation of proteins and peptides up to 116 kDa was successfully achieved using this system.     

Heavy charged Higgs boson production at next generation $\gamma\gamma$ colliders

We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the one of the top quark, at future Linear Colliders operating in mode at the TeV energy scale. Final states with one or two bosons are considered, as produced by both tree- and loop-level interactions. Received: 8 November 2002 / Revised version: 12 February 2003 / Published online: 13 May 2003 RID="a" ID="a" e-mail: stefano.moretti@cern.ch RID="b" ID="b" e-mail: kanemu@post.kek.jp