NiCoFe/C cathode electrocatalysts for direct ethanol fuel cells

A direct ethanol fuel cell (DEFC), which is less prone to ethanol crossover, is reported. The cell consists of PtRu/C catalyst as the anode, Nafion^® 117 membrane, and Ni–Co–Fe (NCF) composite catalyst as the cathode. The NCF catalyst was synthesized by mixing Ni, Co, and Fe complexes into a polymer matrix (melamine-formaldehyde resins), followed by heating the mixture at 800 °C under inert atmosphere. TEM and EDX experiments suggest that the NCF catalyst has alloy structures of Ni, Co and Fe. The catalytic activity of the NCF catalyst for the oxygen reduction reaction (ORR) was compared with that of commercially available Pt/C (CAP) catalyst at different ethanol concentrations. The decrease in open circuit voltage (V_oc) of the DEFC equipped with the NCF catalysts was less than that of CAP catalyst at higher ethanol concentrations. The NCF catalyst was less prone to ethanol oxidation at cathode even when ethanol crossover occurred through the Nafion^®117 film, which prevents voltage drop at the cathode. However, the CAP catalyst did oxidize ethanol at the cathode and caused a decrease in voltage at higher ethanol concentrations.     

Thickness dependence of H2 gas sensor in amorphous SnQx films prepared by ion-beam sputtering

Amorphous SnO_x films were deposited by ion-beam sputtering on sintered alumina substrates. Amorphous film sensors were prepared by annealing the films at 300° C for 2 h in air. The thickness dependence of resistivity and hydrogen gas sensitivity were measured at 150° C over the thickness range 1 to 700 nm. A resistivity maximum was observed in ultrathin films. Resistivity increased by three orders of magnitude with increasing film thickness from 0.9 to 7.4 nm and then decreased by five orders of magnitude from 7.4 to 35 nm. Ultrathin film sensors showed sensitivity maxima around a thickness of 10 nm. Sensitivity and resistivity of ultrathin films were significantly influenced by the thermal expansion coefficient and the surface state of the substrate.     

Properties of indium oxide/tin oxide multilayered films prepared by ion-beam sputtering

The preparation and characterization of indium oxide (InO _x )/tin oxide (SnO _y ) multilayered films deposited by ion-beam sputtering are described and compared with indium tin oxide (ITO) films. The structure and the optoelectrical properties of the films are studied in relation to the layered structures and the post-deposition annealing. Low-angle X-ray diffraction analysis showed that most films retained the regular layered structures even after annealing at 500° C for 16 h. As an example, we obtained a resistivity of 6×10^–4 cm and a transparency of about 85% in the visible range at a thickness of 110 nm in a multilayered film of InO _x (2.0 nm)/SnO _y (0.2 nm)×50 pairs when annealed at 300° C for 0.5 h in air. Hall coefficient measurements showed that this film had a mobility of 17 cm² V^–1 sec^–1 and a carrier concentration (electron density) of 5×10²⁰ cm^–3.     

Smooth Scheduling under Variable Rates or the Analog-Digital Confinement Game

This work considers non-terminating scheduling problems in which a system of multiple resources serves clients having variable needs. The system has m identical resources and n clients; in each time slot each resource may serve at most one client; in each such slot t each client γ has a rate, a real number ρ _γ (t), that specifies his needs in this slot. The rates satisfy the restriction ∑ _γ ρ _γ (t)≤m for any slot t. Except of this restriction, the rates can vary in arbitrary fashion. (This contrasts most prior works in this area in which the rates of the clients are constant.) The schedule is required to be smooth as follows: a schedule is Δ -smooth if for all time intervals I the absolute difference between the amount of service received by each client γ to his nominal needs of ∑ _t∈I ρ _γ (t) is less than Δ. Our objective are online schedulers that produce Δ-smooth schedules where Δ is a small constant which is independent of m and n. Our paper constructs such schedulers; these are the first online Δ-smooth schedulers, with a constant Δ, for clients with arbitrarily variable rates in a single or multiple resource system. Furthermore, the paper also considers a non-concurrent environment in which there is an additional restriction that each client is served at most once in each time slot; it presents the first online smooth schedulers for variable rates under this restriction. The above non-concurrent restriction is crucial in some applications (e.g., CPU scheduling). It has been pointed out that this restriction “adds a surprising amount of difficulty” to the scheduling problem. However, this observation was never formalized and, of course, was never proved. Our paper formalizes and proves some aspects of this observation. Another contribution of this paper is the introduction of a complete information, two player game called the analog-digital confinement game. In such a game pebbles are located on the real line; the two players, the analog player and the digital player, take alternating turns and each one, in his turn, moves some of the pebbles; the digital player moves the pebbles backwards by discrete distances while the analog player moves the pebbles forward by analog distances; the aim of the analog player is to cause one pebble (or more) to escape a pre-defined real interval while the aim of the digital player is to confine the pebbles into the interval. We demonstrate that this game is a convenient framework to study the general question of how to approximate an analog process by a digital one. All the above scheduling results are established via this game. In this derivation, the pebbles represent the clients, the analog player generates the needs of the clients and the digital player generates the schedule. Dedicated to the memory of Professor Shimon Even for his inspiration and encouragement     

Advanced methods for displays and remote control of robots

An in-depth evaluation of the usability and situation awareness performance of different displays and destination controls of robots are presented. In two experiments we evaluate the way information is presented to the operator and assess different means for controlling the robot. Our study compares three types of displays: a “blocks” display, a HUD (head-up display), and a radar display, and two types of controls: touch screen and hand gestures. The HUD demonstrated better performance when compared to the blocks display and was perceived to have greater usability compared to the radar display. The HUD was also found to be more useful when the operation of the robot was more difficult, i.e., when using the hand-gesture method. The experiments also pointed to the importance of using a wide viewing angle to minimize distortion and for easier coping with the difficulties of locating objects in the field of view margins. The touch screen was found to be superior in terms of both objective performance and its perceived usability. No differences were found between the displays and the controllers in terms of situation awareness. This research sheds light on the preferred display type and controlling method for operating robots from a distance, making it easier to cope with the challenges of operating such systems.     

Electrochemical analysis of zincate treatments for Al and Al alloy films

Electrochemical behavior of Al and Al alloy films in zincate solution was investigated to elucidate the effect of the zincate pretreatment for electroless NiP deposition, which is used for under bump metallization for LSI interconnects. The immersion potential for AlCu and AlSiCu, immediately reached to constant, which was almost equal potential to zinc reference electrode. The corrosion current for the AlCu and AlSiCu films was larger than that of the Al and AlSi films in the zincate solution. It was also confirmed that the deposited Zn at the surface of AlCu and AlSiCu films possessed smaller grain size and larger amount of nucleation, resulted in the formation of flat NiP films.     

Effect of the addition of silver compounds during the pyrolysis of manganese nitrate on tantalum anodic oxide film

A study of the pyrolysis of an aqueous solution of manganese nitrate in the presence of silver compounds has been carried out. Thermal analysis showed that the MnO₂ formation temperature and the transformation temperature from MnO₂ to Mn₂O₃ shifted towards a lower temperature in the presence of silver acetate. A large particle-size and high crystallinity MnO₂ was formed; this may be a useful method of making an excellent tantalum capacitor with high capacitance.     

"Where similarity beats redundancy: The importance of context, higher order similarity, and response assignment": Correction to Eidels, Townsend, and Pomerantz (2008).

Reports an error in "Where similarity beats redundancy: The importance of context, higher order similarity, and response assignment" by Ami Eidels, James T. Townsend and James R. Pomerantz (Journal of Experimental Psychology: Human Perception and Performance, 2008[Dec], Vol 34[6], 1441-1463). The DOIs for the article and the supplemental materials were incorrectly listed. The correct DOIs are provided in the erratum. (The following abstract of the original article appeared in record 2008-16831-008.) People are especially efficient in processing certain visual stimuli such as human faces or good configurations. It has been suggested that topology and geometry play important roles in configural perception. Visual search is one area in which configurality seems to matter. When either of 2 target features leads to a correct response and the sequence includes trials in which either or both targets are present, the result is a redundant-target paradigm. It is common for such experiments to find faster performance with the double target than with either alone, something that is difficult to explain with ordinary serial models. This redundant-targets study uses figures that can be dissimilar in their topology and geometry and manipulates the stimulus set and the stimulus-response assignments. The authors found that the combination of higher order similarity (e.g., topological) among the features in the stimulus set and response assignment can effectively overpower or facilitate the redundant-target effect, depending on the exact nature of the former characteristics. Several reasonable models of redundant-targets performance are falsified. Parallel models with the potential for channel interactions are supported by the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)