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Electrolysis of Titanium in Heavy Water
Get PDFThe purpose of these studies was to determine if results similar to those of Fleischmann and Pons could be obtained using a titanium cathode instead of palladium in an electrolysis in a heavy water cell. The electrolyte consists of D2O and H2SO4. Two experiments have been performed to examine the features of this electrolysis. As titanium shows the same properties to attract hydrogen, it seemed possible that excess heat could be produced. Radiation was monitored, and the surface of the titanium cathode was examined before and after electrolysis for any changes in the morphology and composition, hoping to discover new elements that can be created only by fusion reactions in the cell, i.e. by transmutation. The heat and radiation effects have been evaluated in comparison to a control cell, using the same electrolyte and current. The only difference was the cathode, which was of platinum. It appears that excess heat is produced during electrolyses of heavy water with a titanium cathode. The amount of this excess heat was 750 cal in a one hour period, an energy gain of 44%. No significant emission of any of the products associated with a classical deuterium-deuterium fusion was observed during either experiment, i.e. heat but no radiation. Unexpected elements were found in both experiments, i.e. K. Cr, Fe, Ni and Zn. Remarkable is the fact that the new elements always occur very close in the periodic table to an impurity element, i.e. Cu and Zn
thin layers on cost effective Si-substrates and novel metallisation concepts for photovoltaic applications
No full textWithin this work the epitaxial solution growth of thin silicon (Si)-layers on cost effectiveSi-substrates was investigated. The properties of these layers were adapted to the processingof thin film solar cells. This technology could help to decrease the shortage of pure Si forphotovoltaic applications in the future.In the course of this study a broad spectrum of growth parameters were varied in order toinvestigate their influence on the quality of the epitaxial layer. It was shown that the use ofthe melt back technique is necessary and in addition the growth rate has to be lower than0.5 µm/min to obtain continuous Si-layers.In order to still enable an industrial application of the LPE technique regarding such low growthrates, a new stack procedure was applied where several substrates were dipped into the growthsolution at once. Using thin layers grown with this technique the efficiency of industriallyprocessed solar cells was essentially improved compared to fast, single grown layers. Opencircuit voltages of nearly 600 mV and fill factors of up to 76.4 % led to a record efficiencyof 10.0 %. Simulations showed that efficiencies above 13 % are possible.During LPE experiments with microscopically grooved substrates an interesting observationled to the idea to take advantage of the wetting properties of the tin solvent in order to metallisethe solar cell. This novel contacting technique is based on the so called Buried Contact SolarCell (BCSC) technology. The cells showed excellent contact properties. Finger resistances of500 mOhm/cm, specific contact resistances in the range of 0.1 mOhm-cm2 and fill factors of up to78 % are comparable with parameters obtained by industrial BCSCs.publishe
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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