1,721,019 research outputs found

    Electrocatalytic Reduction Of Peroxodisulfate In 0.5 M Naoh At Copper Electrodes. A Combined Quartz Microbalance And Rotating Ring/disc Electrode Investigation

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    From an electrochemical investigation by means of an electrochemical quartz microbalance, a rotating disc electrode, and a ring/disc electrode, two mechanisms for the reduction of S2O82- became apparent. Besides the well-known outer-sphere cathodic reduction, a catalytic mechanism of S2O82- reduction operates in a potential range between the surface oxide region (≈-0.5 V/SCE) and -1.0 V/SCE. It involves the chemical oxidation of the copper surface to a soluble Cu(I) species. The catalytic mechanism is concluded to result from the specific interaction between S2O82- and the Cu surface modified by the presence of subsurface oxygen.1011424112414Frumkin, A.N., (1933) Z. Phys. Chem. (Munich), 164, p. 121Wolf, W., Ye, J., Purgand, M., Eiswirth, M., Doblhofer, K., (1992) Ber. Bunsen-Ges. Phys. Chem., 96, p. 1797Flätgen, G., Krischer, K., Ertl, G., (1995) Z. Naturforsch., 50 A, p. 1097Flätgen, G., Krischer, K., (1995) J. Chem. Phys., 103, p. 5428Flätgen, G., Krischer, K., Pettinger, B., Doblhofer, K., Junkes, H., Ertl, G., (1995) Science, 269, p. 668Flätgen, G., Krischer, K., (1995) Phys. Rev. E, 51, p. 3997Flätgen, G., Krischer, K., Ertl, G., J. Electroanal. Chem., , in pressKoper, M.T.M., (1996) Ber. Bunsen-Ges. Phys. Chem., 100, p. 497Damaskin, B.B., Safonov, V.A., Fedorovich, N.V., (1993) J. Electroanal. Chem., 349, p. 1Latimer, W.M., (1952) The Oxidation States of the Elements and Their Potentials in Aqueous Solutions, , Prentice-Hall: New YorkLevie, M.G., Migliorini, E., Ercolini, G., (1908) Gazz. Chim. Ital., 38, p. 583Bond, G.C., Hill, G.M., Tennison, R., (1959) J. Chem. Soc., p. 33Müller, L., (1967) J. Electroanal. Chem., 13, p. 275Müller, L., Wetzel, R., Otto, H., (1970) J. Electroanal. Chem., 24, p. 175Mark, H.B., Anson, F.C., (1963) J. Electroanal. Chem., 6, p. 251Burke, L.D., O'Sullivan, J.F., O'Dwyer, K.J., Scannell, R.A., Ahern, M.J.G., McCarthy, M.M., (1990) J. Electrochem. Soc., 137, p. 2476Desilvestro, J., Weaver, M.J., (1987) J. Electroanal. Chem., 234, p. 237Ye, J., Wolf, W., Doblhofer, K., Eiswirth, M., (1994), Unpublished work. Wolf, W. Ph.D. Thesis, Frei Universität Berlin, BerlinHärtinger, S., Pettinger, B., Doblhofer, K., (1995) J. Electroanal. Chem., 397, p. 335Soares, D.M., (1993) Meas. Sci. Technol., 4, p. 549Fruböse, C., Doblhofer, K., Soares, D.M., (1993) Ber. Bunsen-Ges. Phys. Chem., 97, p. 475Sauerbrey, G., (1959) Z. Phys., 155, p. 206Albery, W.J., Bruckenstein, S., (1966) Trans. Faraday Soc., 62, p. 1920Ikemiya, N., Kubo, T., Hara, S., (1995) Surf. Sci., 323, p. 81Strehblow, H.H., Titze, B., (1980) Electrochim. Acta, 25, p. 839Shirkhanzadeh, M., Thompson, G.E., Ashworth, V., (1990) Corr. Sci., 31, p. 293Miller, B., (1969) J. Electrochem. Soc., 116, p. 1675Tindall, G.W., Bruckenstein, S., (1969) J. Electroanal. Chem., 22, p. 367Schubert, H., Tegetmeyer, U., Schlögl, R., (1994) Cat. Lett., 28, p. 383Schedl-Niedrig, T., Bao, X., Muhler, M., Neisius, T., Schlögl, R., (1995) Annual Fachbeirat of Fritz-Haber-Institut of the Max-Planck-Gesellschaft, , Abstract AC12, BerlinWerner, H., Demuth, D., Schubert, H., Weinberg, G., Braun, T., Herein, D., Schlögl, R., (1995) Annual Fachbeirat of Fritz-Haber-Institut of the Max-Planck-Gesellschaft, , Abstract AC13, BerlinPolak, M., (1994) Surf. Sci., 321, p. 249Carley, A.F., Davies, P.R., Roberts, M.W., Vicent, D., (1994) Top. Catal., 1, p. 35Davies, P.R., Roberts, M.W., Shukla, N., Vicent, D., (1995) Surf. Sci., 325, p. 5

    Electrochemical generation of light in conjugated polymers

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    Polyphenylene vinylene (PPV) and its derivatives represent the prototype systems for the realization of luminescent layers in electroluminescent LEDs. Recently they have been important in the development of light emitting electrochemical cells (LEC). The luminescent properties of the conducting polymer layer are determined by not only the chemical species constituting the conducting polymer, but also the solid electrolyte of the electrochemical cell. In the present paper is reported a kinetics study of electrochemiluminescence (ECL) produced by 4-methoxy(2'ethylhexoxyl)-2,5-poly(phenylene vinylene), denoted herein as MEH-PPV, thin coatings when different electrochemical conditions are adopted. To our knowledge this represents one of the few critical studies on the features of ECL produced by polymer modified electrodes

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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