1,720,959 research outputs found
Expanding the radioanalysts toolbox: using the latest generation plasma mass spectrometers for nuclear waste characterisation
No full textThis project investigates the application of sector field inductively coupled mass spectrometry (ICP-SFMS) in low-level radionuclide detection in environmental samples and low-level nuclear waste. The aim was to develop robust and sensitive procedures for measuring medium-long lived emitters of interest to various Nuclear Decommissioning Authority (NDA) sites. ICP-SFMS has been investigated for the measurement of the significant fission product radionuclides of caesium (135Cs and 137Cs) and strontium (90Sr). In the case of some shorter-lived radionuclides such as 90Sr, ICP-SFMS can achieve sensitivities that rival existing radiometric techniques, whilst offering a significant improvement in the speed of analysis. Additionally, long-lived low abundance radionuclides such as 135Cs are not detectable using radiometric techniques, but can be quantified by ICP-SFMS, which is important given their major contribution to the long-term radiological risk associated with deep geological disposal. Measurement of 135Cs also enables measurement of the 135Cs/137Cs ratio, which varies with the source of nuclear contamination, and therefore can provide a powerful forensic tool compared to radiometric 137Cs detection alone.ICP-SFMS has been proven to achieve high sensitivities that will enable low-level radionuclide detection. In order to reach these sensitivities, it is critical to ensure removal of interfering elements that otherwise significantly impact the accuracy of measured values. This led to the development of novel and efficient chemical separation procedures that achieve both a high analyte recovery, and effective decontamination of interferences, which have been proven to be effective for a range of sample matrices including seawater and sediments. The combination of imaginative sample preparation procedures and use of new generation ICP-SFMS offer a streamlining of the process that will contribute to faster more sensitive assessment and clean-up of nuclear sites. This will lead to a reduction in analytical timescales and reduce the demand on existing analytical facilities, benefitting site operators and the NDA
Recent contributions to the rapid screening of radionuclides in emergency responses and nuclear forensics
Full text linkThe ability to efficiently identify potential radiological threats or actual radioactive assaults on society and the environment demands a sophisticated and dedicated infrastructure comprising specialised personnel, mobile and fixed laboratories and advanced analytical instrumentation. Most developed countries have such systems but ensuring a long-term and resilient capability is recognised as a perennial challenge. National government laboratories specialising in nuclear forensics play a key role in maintaining capability but these organisations continue to benefit significantly from interdisciplinary and innovative contributions derived from universities and other research institutions. This review provides an insight into the range of technologies used and also provides a broad overview of applied techniques and instrumentation that contribute to rapid screening and analysis in the context of nuclear forensics and radiological emergencies
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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