Performance of surface ionic conduction single chamber fuel cell prepared by the sol gel method

The performance of surface ionic conduction single chamber fuel cell (SIC‐SCFC) prepared by the sol gel method was studied on electric characteristics due to the differences of the operating temperature and humidity, the electrode distance and electrolyte film depth, and multiple cells with the series and parallel connections. The SIC–SCFC was arranged the both anode of Pt and cathode of Au on the boehmite electrolyte. The open circuit voltage (OCV) of single cell achieved a maximum of 530mV in the dry gas mixtures of O₂/H₂=50% in room temperature operation, and but it became decrease as over 60%. The OCV was maintained the constant value between operating temperatures of 30°C to 80°C, and but it was decreased sharply at over 90°C because a humidity on the cell became lower as increasing operating temperature. Then, the cell property was improved to 120°C by adding to the humidity of 70% using a humidifier. The electrode distance and the electrolyte film depth of SIC‐SCFC found to be contributed to the reductions of the cell resistance and the surface roughness on the electrode, respectively. Moreover, the power property of SIC‐SCFC was significantly improved by cell stacks comprised of the series or parallel connection of a cell.     

Effect of superfine particles of alumina incorporated in the cavities of mordenite in enhancing selectivity

Alumina has been incorporated in the cavities of mordenite by the hydrolysis of Al³⁺ ions in the cavities with moist ammonia gas, following calcination at 450°C. The incorporation of the superfine particles of alumina into the cavities of the mordenite is assessed on the basis of the data of MAS ²⁷Al NMR measurements, X-ray powder diffraction and the amount of saturated adsorption of nitrogen for FAL/MZ. The acid properties, assessed using NH₃ TPD and FTIR studies, show the presence of Brønsted and Lewis acid sites on the catalyst, and an increase in acidic sites on incorporating alumina. The dehydrogenation selectivities of FAL/MZ, Al³⁺/MZ, H⁺/MZ, and Na⁺/MZ have been investigated. Brønsted acid sites largely enhance the ring-cleavage, whereas this incorporation of superfine particles of alumina significantly suppresses the ring-cleavage. Therefore, the incorporation of the superfine particles increases remarkably in the cyclohexene selectivity.     

Time–frequency analysis of lamb waves caused by partial discharges and free particles in GIS

We investigated the propagation properties of Lamb waves in a GIS tank, using time–frequency analysis to diagnose the insulation performance of GIS. We measured the acoustic signals excited by metallic particles colliding with the tank sheath, and those emitted by partial discharge in the GIS. The wavelet transform was used to decompose the wave data into its time–frequency components. As a result, it was confirmed that Lamb waves with the dispersive property of the velocity are excited and propagate in a spiral path along the tank wall due to the cylindrical structure of the tank. Taking these results into consideration, we propose a new technique for identification of defect locations in GIS based on time–frequency analysis of acoustic signals with the wavelet transform. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(3): 25–32, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10163     

Reforming of Methane with Carbon Dioxide over a Catalyst Consisting of Ruthenium Metal and Cerium Oxide Supported on Mordenite

Reforming of CH₄ with CO₂ proceeds at 400 °C over a catalyst consisting of ruthenium metal and CeO₂ highly dispersed on mordenite. The catalyst, Ru-CeO₂/MZ, is highly active for the reforming of CH₄ under the conditions at which a carbon formation reaction is thermodynamically apt to take place. The reforming selectively forms H₂ and CO. An increase in the weight of the catalyst resulting from carbon deposits was scarcely observed. IR spectra for the catalyst indicate that the reforming proceeds via the formation of the intermediate species such as Ru-CO and Ru-CH_x on the surface of ruthenium. The data of H₂ adsorption support the idea that ruthenium is highly dispersed in Ru-CeO₂/MZ.     

Self-aligned fabrication of single crystal diamond gated field emitter array

This paper describes a self-aligned fabrication process for diamond gated field emitter array (FEA). Utilizing the non-conformal coverage sputtering conditions of silicon oxide, an interesting “sphere on cone” structure is formed on diamond nano tip array, which is the key point of gate hole opening process. This structure causes shadowing at certain regions of side-wall during Ti / Au gate metal deposition. Removal of “sphere” by wet etching leads to the successful fabrication of a single crystalline diamond gated FEA. Scanning electron microscope observations reveal the fabrication of a uniform emitter array with tip radius of curvature (20 nm) and gate hole (1.4 μm). We also confirmed that no noticeable physical damage exists on tip. In field emission characteristics of the fabricated single crystal diamond gated FEA, gate voltage control of field emission current is realized.     

Transverse colonic stenosis

A 3-year child presented with episodic lower abdominal pain; during the eighth attack, a mass was palpable in the left upper quadrant, and a barium enema revealed a stenotic area in the transverse colon. This was resected and an uneventful postoperative course followed. Subsequently, the child has remained symptom-free. instruments are no longer in use.     

Choroid plexus carcinoma in infants: report of two cases and review of the literature

The new cytostatics titanocene dichloride and vinorelbine were compared to cisplatin and paclitaxel using a human ovarian cancer xenografts model. Biopsy material from a native human ovarian carcinoma was expanded and transplanted into 96 nude mice. The animals were divided into six treatment groups: cisplatin 3 x 4 mg/kg, paclitaxel 5 x 26 mg/kg, vinorelbine 1 x 20 mg/kg, titanocene dichloride 3 x 30 mg/kg, titanocene dichloride 3 x 40 mg/kg and a control group treated with 0.9% saline. Each experiment was repeated with eight mice in each treatment group. Treatment groups were evaluated in terms of average daily increase in tumor volume and average daily body weight increase of nude mice based on slopes of least-square regressions performed on individual animals. The slope factors alpha and beta of the body weight (alpha) and tumor volume changes (beta) within each group during the course of an experiment were calculated. Both a statistically significant decrease (p<0.05) in the body weight of the experimental animals (cisplatin: alpha = -0.5163, vinorelbine: alpha = -0.6598, paclitaxel: alpha = -0.6746, titanocene dichloride 3 x 30 mg/kg: alpha = -0.6259, titanocene dichloride 3 x 40 mg/kg: alpha = -0.7758) and a significant reduction (p<0.05) of the increase in tumor volume (cisplatin: beta = 12.049, vinorelbine: beta = 0.504, paclitaxel: beta = -1.636, titanocene dichloride 3 x 30 mg/kg: beta = 6.212, titanocene dichloride 3 x 40 mg/kg: beta= -0.685) was shown in all treated groups compared to the control group (alpha = -0.1398; beta = 23.056). No significant weight changes were observed between the individually treated groups. A statistically significant reduction of the tumor growth occured under paclitaxel (beta = -1.636), vinorelbine (beta = 0.504) and titanocene dichloride medication 3 x 40 mg/kg (beta = -0.685), as compared to the group treated with cisplatin (beta = 12.049). We found titanocene dichloride to be as effective as paclitaxel and more effective than cisplatin. Vinorelbine seems to be a very effective antineoplastic agent exhibiting a significant higher cytostatic effect than cisplatin. Both titanocene dichloride and vinorelbine provide new therapeutic options in women with ovarian carcinoma not responding to standard chemotherapy.     

An Artificial Sensory Neuron with Tactile Perceptual Learning

Sensory neurons within skin form an interface between the external physical reality and the inner tactile perception. This interface enables sensory information to be organized identified, and interpreted through perceptual learning—the process whereby the sensing abilities improve through experience. Here, an artificial sensory neuron that can integrate and differentiate the spatiotemporal features of touched patterns for recognition is shown. The system comprises sensing, transmitting, and processing components that are parallel to those found in a sensory neuron. A resistive pressure sensor converts pressure stimuli into electric signals, which are transmitted to a synaptic transistor through interfacial ionic/electronic coupling via a soft ionic conductor. Furthermore, the recognition error rate can be dramatically decreased from 44% to 0.4% by integrating with the machine learning method. This work represents a step toward the design and use of neuromorphic electronic skin with artificial intelligence for robotics and prosthetics.     

Metal–Ligand Based Mechanophores Enhance Both Mechanical Robustness and Electronic Performance of Polymer Semiconductors

The backbone of diketopyrrolopyrrole-thiophene-vinylene-thiophene-based polymer semiconductors (PSCs) is modified with pyridine (Py) or bipyridine ligands to complex Fe(II) metal centers, allowing the metal–ligand complexes to act as mechanophores and dynamically crosslink the polymer chains. Mono- and bi-dentate ligands are observed to exhibit different degrees of bond strengths, which subsequently affect the mechanical properties of these Wolf-type-II metallopolymers. The counter ion also plays a crucial role, as it is observed that Py-Fe mechanophores with non-coordinating BPh₄^– counter ions (Py-FeB) exhibit better thin film ductility with lower elastic modulus, as compared to the coordinating chloro ligands (Py-FeC). Interestingly, besides mechanical robustness, the electrical charge carrier mobility can also be enhanced concurrently when incorporating Py-FeB mechanophores in PSCs. This is a unique observation among stretchable PSCs, especially that most reports to date describe a decreased mobility when the stretchability is improved. Next, it is determined that improvements to both mobility and stretchability are correlated to the solid-state molecular ordering and dynamics of coordination bonds under strain, as elucidated via techniques of grazing-incidence X-ray diffraction and X-ray absorption spectroscopy techniques, respectively. This study provides a viable approach to enhance both the mechanical and the electronic performance of polymer-based soft devices.     

Gaze direction based vehicle teleoperation method with omnidirectional image stabilization and automatic body rotation control

In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method.