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Abstract  

The electron capture processes in the mixtures containing halocarbon (CH2F2 or CHF3) and nitrogen as well as halocarbon, oxygen and carbon dioxide have been investigated. The mechanism has been revealed and the corresponding rate constants have been determined.

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Abstract  

The National Citation Report (NCR) is an integrated citation file supplied by the Institute for Scientific Information (ISI), of an individual country's articles in science and social sciences. Our experience with the NCR database for Mexico suggests that this is an important addition to the tools available for carrying out bibliometric analysis of research performance. However, in order to generate reliable and accurate indicators using these datafiles we recommend that these be handled by specialists well acquainted with the ISI information products and with the scientific setup of the country concerned.

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Scientometrics
Authors:
J. A. García
,
Rosa Rodriguez-Sánchez
, and
J. Fdez-Valdivia

Abstract

Here we show a longitudinal analysis of the overall prestige of first quartile journals during the period between 1999 and 2009, on the subject areas of Scopus. This longitudinal study allows us to analyse developmental trends over times in different subject areas with distinct citation and publication patterns. To this aim, we first introduce an axiomatic index of the overall prestige of journals with ranking score above a given threshold. Here we demonstrate that, between 1999 and 2009, there was high and increasing overall prestige of first quartile journals in only four areas of Scopus. Also, there was high and decreasing overall prestige of first quartile journals in five areas. Two subject areas showed high and oscillating overall prestige of first quartile journals. And there was low and increasing overall prestige in four areas, since the 1999.

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Abstract

Here we show a comparison of top economics departments in the US and EU based on a summary measure of the multidimensional prestige of influential papers in 2010. The multidimensional prestige takes into account that several indicators should be used for a distinct analysis of structural changes at the score distribution of paper prestige. We argue that the prestige of influential articles should not only consider one indicator as a single dimension, but in addition take into account further dimensions, since several different indicators have been developed to evaluate the impact of academic papers. After having identified the multidimensionally influential articles from an economics department, their prestige scores can be aggregated to produce a summary measure of the multidimensional prestige of research output of this department, which satisfies numerous properties.

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Concentration of carbon (C), oxygen (O), nitrogen (N), magnesium (Mg), aluminium (Al), silicon (Si), phosphorus (P), mercury (Hg), sulphur (S), lead (Pb), chlorine (Cl), potassium (K), cadmium (Cd), calcium (Ca), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu) and zinc (Zn), in the form of weight percentage, in the needles of different age classes, current and previous year one, of two sites, Risnjak National Park and Donja Dobra (control), were measured by X-ray microanalysis (EDAX) in the Scanning Electron Microscope in silver fir trees (Abies alba Mill.). The analysis suggests that accumulation of elements, in both years, particularly that of heavy metals, appeared in polluted site, like Risnjak, in the higher amount, whereas in non polluted, like Donja Dobra, in the lower amount. Moreover, it seems likely that elements at the first sites were accumulated and contaminated in very young current year needles, while in non polluted in somewhat older, the previous year ones.

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Abstract  

Liquid scintillation spectrometry has become the most widespread method for quantitative analysis of low level -emitters in environmental samples. This technique has been applied in the measurements of 241Pu, 3H and 90Sr in seawater and sediment samples. 241Pu can be measured by direct analysis of an electrodeposited source using - discrimination or by extraction of electrodeposited plutonium into a liquid form compatible with scintillation cocktail. Sediment from Mururoa and Fangataufa atolls showed activities ranging from 18 to 44 Bq/kg. A sediment profile sampled around Bikini Atoll in 1997 showed 241Pu activities ranging from 0.3 to 30 Bq/kg. 3H activities in pore water sediment from Mururoa and Fangataufa atolls were of the order of 103 Bq/m3 which demonstrated its underground origin. 90Sr was measured in the presence of 90Y. The counting efficiency was 92.41.5% and the background 0.027±0.001 s-1. The average chemical recovery for 90Sr was 673%.

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Scientometrics
Authors:
J. A. García
,
Rosa Rodriguez-Sánchez
,
J. Fdez-Valdivia
, and
J. Martinez-Baena

Abstract

Here we study the relationship between journal quartile rankings of ISI impact factor (at the 2010) and journal classification in four impact classes, i.e., highest impact, medium highest impact, medium lowest impact, and lowest impact journals in subject category computer science artificial intelligence. To this aim, we use fuzzy maximum likelihood estimation clustering in order to identify groups of journals sharing similar characteristics in a multivariate indicator space. The seven variables used in this analysis are: (1) Scimago Journal Ranking (SJR); (2) H-Index (H); (3) ISI impact factor (IF); (4) 5-Year Impact Factor (5IF); (5) Immediacy Index (II); (6) Eigenfactor Score (ES); and (7) Article Influence Score (AIS). The fuzzy clustering allows impact classes to overlap, thereby accommodating for uncertainty related to the confusion about the impact class attribution for a journal and vagueness in impact classes definition. This paper demonstrates the complex relationship between quartiles of ISI impact factor and journal impact classes in the multivariate indicator space. And that several indicators should be used for a distinct analysis of structural changes at the score distribution of journals in a subject category. Here we propose it can be performed in a multivariate indicator space using a fuzzy classifier.

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Summary  

A Radioanalytical Emergency Procedures Manual Database (REPMD) will be an important tool to assist laboratories preparing for emergency response to a sudden release of radioactivity into the environment. The collection and systematic organization of existing sampling, screening and radioanalytical methods will enable laboratories to assess the appropriate methodologies for their use. REPMD is intended to be flexible, searchable, and interactive to accommodate a wide range of available techniques while being protected from unauthorized modifications. Website access by the world-wide scientific community will make the database a foundation for international comparison. The information in the database will also serve as a comprehensive and periodically updated source of methods and procedures suitable for training programs and rapid reference.

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Abstract

A university may be considered as having dimension-specific prestige in a scientific field (e.g., physics) when a particular bibliometric research performance indicator exceeds a threshold value. But a university has multidimensional prestige in a field of study only if it is influential with respect to a number of dimensions. The multidimensional prestige of influential fields at a given university takes into account that several prestige indicators should be used for a distinct analysis of the influence of a university in a particular field of study. After having identified the multidimensionally influential fields of study at a university their prestige scores can be aggregated to produce a summary measure of the multidimensional prestige of influential fields at this university, which satisfies numerous properties. Here we use this summary measure of multidimensional prestige to assess the comparative performance of Spanish Universities during the period 2006–2010.

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Abstract  

241Pu was measured in reference materials and marine samples using a novel method based on rare earth fluoride co-precipitation followed by liquid scintillation spectrometry (LSS). Disc sources used for -spectrometry of 238Pu and 239+240Pu were leached with concentrated nitric acid before neodymium fluoride co-precipitation to scavenge plutonium in the lower oxidation states was carried out. After the determination of the chemical recovery by -spectrometry, the precipitate was recovered in a H3BO3/HNO3 based dissolver and mixed with Packard Insta-GelÒ Plus cocktail before LSS. Reasonable agreement has been obtained between the results obtained using this methods and the data obtained by direct disc analysis by LSS and ICP-MS. The 241Pu/239+240Pu ratios were coherent with the expected origin of the Pu contaminant in the marine environment showing the validity of the method.

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