9,748 research outputs found

    Comment on "Anderson transition in disordered graphene"

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    We comment on a recent letter by Amini et al. (EPL 87, 37002 (2009)) concerning the existence of a mobility edge in disordered graphene.Comment: 3 pages, 3 figure

    Euler characteristic and quadrilaterals of normal surfaces

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    Let MM be a compact 3-manifold with a triangulation Ï„\tau. We give an inequality relating the Euler characteristic of a surface FF normally embedded in MM with the number of normal quadrilaterals in FF. This gives a relation between a topological invariant of the surface and a quantity derived from its combinatorial description. Secondly, we obtain an inequality relating the number of normal triangles and normal quadrilaterals of FF, that depends on the maximum number of tetrahedrons that share a vertex in Ï„\tau.Comment: 7 pages, 1 figur

    The development of an electrochemical technique for in situ calibrating of combustible gas detectors

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    A program to determine the feasibility of performing in situ calibration of combustible gas detectors was successfully completed. Several possible techniques for performing the in situ calibration were proposed. The approach that showed the most promise involved the use of a miniature water vapor electrolysis cell for the generation of hydrogen within the flame arrestor of a combustible gas detector to be used for the purpose of calibrating the combustible gas detectors. A preliminary breadboard of the in situ calibration hardware was designed, fabricated and assembled. The breadboard equipment consisted of a commercially available combustible gas detector, modified to incorporate a water vapor electrolysis cell, and the instrumentation required for controlling the water vapor electrolysis and controlling and calibrating the combustible gas detector. The results showed that operation of the water vapor electrolysis at a given current density for a specific time period resulted in the attainment of a hydrogen concentration plateau within the flame arrestor of the combustible gas detector

    Revisiting and extending a response latency measure of inclusion of the other in the self

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    Although the concept of inclusion of the other in the self (IOS) has been successfully assessed with explicit self-report measures, implicit procedures have been neglected in past literature. The present article explores the validity of such an implicit measure by proposing several extensions and adaptions. We addressed methodological problems of a me/not-me response latency task developed in this literature by proposing changes in material, calculation of indices and implemented the task in an online environment. We also addressed earlier problems with statistical power and proposed a more powerful way of statistical analyses using mixed models. The me/not-me task is based on the idea that higher overlap between self and other traits results in faster response times of characterizing such a trait as descriptive of the self. This relationship should be observed for close others but not for non-close others. In a sample of 339 U.S American adults, we experimentally manipulated the nature of the target (close vs. distant) and participants engaged in the adapted me/not-me paradigm. Results indicated that trait match had a stronger negative effect on response times for participants in the close condition. The effect was also stronger for participants rating the target higher on the IOS self-report scale. We also provided convergent validity of the me/not-me procedure with other constructs ostensibly measuring interpersonal closeness. Future applications and possible limitations are discussed.info:eu-repo/semantics/acceptedVersio

    Evaluation and characterization of the methane-carbon dioxide decomposition reaction

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    A program was conducted to evaluate and characterize the carbon dioxide-methane (CO2-CH4) decomposition reaction, i.e., CO2 + CH4 = 2C + 2H2O. The primary objective was to determine the feasibility of applying this reaction at low temperatures as a technique for recovering the oxygen (O2) remaining in the CO2 which exits mixed with CH4 from a Sabatier CO2 reduction subsystem (as part of an air revitalization system of a manned spacecraft). A test unit was designed, fabricated, and assembled for characterizing the performance of various catalysts for the reaction and ultraviolet activation of the CH4 and CO2. The reactor included in the test unit was designed to have sufficient capacity to evaluate catalyst charges of up to 76 g (0.17 lb). The test stand contained the necessary instrumentation and controls to obtain the data required to characterize the performance of the catalysts and sensitizers tested: flow control and measurement, temperature control and measurement, product and inlet gas analysis, and pressure measurement. A product assurance program was performed implementing the concepts of quality control and safety into the program effort

    Six-man, self-contained carbon dioxide concentrator system

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    A six man, self contained electrochemical carbon dioxide concentrating subsystem was successfully designed and fabricated. It was a preprototype engineering model designed to nominally remove 6.0 kg (13.2 lb) CO2/day with an inlet air CO2 partial pressure of 400 N/sq m (3 mm Hg) and an overcapacity removal capability of 12.0 kg (26.4 lb) CO2/day. The design specifications were later expanded to allow operation at space station prototype CO2 collection subsystem operating conditions
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