1,721,243 research outputs found
The Staebler-wronski Effect In Amorphous Germanium
No full textWe report the observation of a metastable Staebler-Wronski effect in hydrogenated amorphous germanium (a-Ge:H) at room temperature. Both metastable and stable (irreversible) increases in the spin density were observed by electron spin resonance (ESR) after irradiation with 1.17 eV light. The inducing and annealing kinetics are compared to the well-studied behavior in hydrogenated amorphous silicon (a-Si:H). © 2004 Published by Elsevier B.V.338-3401 SPEC. ISS.374377Staebler, D.L., Wronski, C.R., (1977) Appl. Phys. Lett., 31, p. 292Dersch, H., Stuke, J., Beichler, J., (1980) Appl. Phys. Lett., 38, p. 456Santos, P.V., Graeff, C.F.D.O., Chambouleyron, I., (1991) J. Non-cryst. Solids, 128, p. 243Eberhardt, K., Bauer, G.H., (1993) J. Non-cryst. Solids, 164-166, p. 19Unold, T., (1994) Mater. Res. Soc. Proc., 336, p. 287Fritzche, H., Stradins, P., Belomoin, G., (1996) Mater. Res. Soc. Symp. Proc., 520, p. 563Cohen, J.D., (2003) Solar Energy Mater. Solar Cells, 78, p. 399Marques, F.C., De Lima Jr., M.M., Taylor, P.C., (1999) Appl. Phys. Lett., 74, p. 3797Marques, F.C., De Lima Jr., M.M., Taylor, P.C., (2002) J. Non-cryst. Solids, 299-302, p. 571Yan, B., Schultz, N., Efros, A.L., Taylor, P.C., (2000) Phys. Rev. Lett., 84, p. 4180Yan, B., Taylor, P.C., (1998) MRS Symp. Proc., 507, p. 787Stutzmann, M., Jackson, W.B., Tsai, C.C., (1985) Phys. Rev. B, 32, p. 23Redfield, D., (1989) Appl. Phys. Lett., 54, p. 398Nitta, S., Takahashi, Y.U., Noda, M., (1981) J. Phys. (Paris), 42, pp. C4-403Schultz, N., Taylor, P.C., (2001) MRS Symp. Proc., 609, pp. A3.4.1Branz, H., (1999) Phys. Rev. B, 59, p. 549
Recombination Mechanism Of Excess Carriers In Hydrogenated Amorphous Germanium
No full textIn this work we report a study of the recombination mechanism of electrons trapped in the conduction band-tail states with holes trapped in the valence band-tail states as a function of the light intensity, G, in hydrogenated amorphous germanium (a-Ge:H). The density of trapped electrons increases with light excitation, but the saturation spin density depends only weakly on the light intensity and increases as G0.17. On the other hand, the characteristic time constant for growth of the light-induced electron spin resonance (LESR) signal, which is related to the recombination lifetimes, follows a power law function, G-0.65. The growth and decay curves can be well fitted by a dispersive model, with a dispersive parameter of about 0.5, assuming bimolecular recombination. © 2002 Elsevier Science B.V. All rights reserved.299-302PART 1571574Knights, J.C., Biegelsen, D.K., Solomon, I., (1977) Solid State Commun., 22, p. 133Street, R.A., Biegelsen, D.K., (1980) Solid State Commun., 33, p. 1159Marques, F.C., De Lima M.M., Jr., Taylor, P.C., (1999) Appl. Phys. Lett., 74 (25), p. 3797Marques, F.C., De Lima M.M., Jr., Taylor, P.C., (2000) J. Non-Cryst. Solids, 266-269, p. 717Stutzmann, M., Stuke, J., (1983) Solid State Commun., 47 (8), p. 635Marques, F.C., Chambouleyron, I., (1989) Proceedings of the Ninth European Conference on Photovoltaic Solar Energy, p. 1042Yan, B., Taylor, P.C., (1998) MRS Symp. Proc., 507, p. 787Yan, B., Schulz, N.A., Efros, A.L., Taylor, P.C., (2000) Phys. Rev. Lett., 84 (18), p. 4180Levin, E.I., Marianer, S., Shklovskii, B.I., (1992) Phys. Rev. B, 45 (11), p. 5906Boulitrop, F., Dunstan, D.J., (1982) Solid State Commun., 44, p. 84
Optically Excited Paramagnetic Centers In Hydrogenated Amorphous Germanium
No full textOptically excited paramagnetic centers in amorphous hydrogenated germanium (a-Ge:H) are reported. The light induced electron spin resonance (LESR) spectra are comprised of two components, which are ascribed to electrons and holes in the conduction- and valence-band-tail states, respectively. There is no evidence of spin pairing, charge defect creation or LESR of Ge dangling bonds. Over about three orders of magnitude in light intensity the decay curves are dispersive with a dispersive parameter of ∼0.5. The spectra are best fit assuming bimolecular recombination. The LESR spin density depends only weakly on the photo-generation rate. © 2000 Elsevier Science B.V. All rights reserved.266-269 B717720Brodsky, M.H., Title, R.S., (1969) Phys. Rev. Lett., 23 (11), p. 581Knights, J.C., Biegelsen, D.K., Solomon, I., (1977) Solid State Commun., 22, p. 133Street, R.A., Biegelsen, D.K., (1980) Solid State Commun., 33, p. 1159Stutzmann, M., Stuke, J., (1983) Solid State Commun., 47 (8), p. 635Marques, F.C., De Lima M.M., Jr., Taylor, P.C., (1999) Appl. Phys. Lett., 74 (25), p. 3797Marques, F.C., Chambouleyron, I., (1989) Proceedings of the Ninth European Photovoltaic Solar Energy Conference, p. 1042Yan, B., Taylor, P.C., (1998) MRS Symp. Proc., 507, p. 787Moore, G.E., (1949) Nat. Bur. Stand., Cir. No. 467, 467Schumm, G., Jackson, W.B., Street, R.A., (1993) Phys. Rev. B, 48 (19), p. 14198Boulitrop, F., Dunstan, D.J., (1982) Solid State Commun., 44, p. 841Levin, E.I., Marianer, S., Shklovskii, B.I., (1992) Phys. Rev. B, 45 (11), p. 590
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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