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Preparation of reference materials for frit chemical analysis
A study was undertaken on how to prepare frit reference materials in which the following elements are analysed: Si, Al, Fe, Ca, Mg, N, K, Ti , Zr, Ba, Pb, Zn, Hf, P, B and Li . The following analytical techniques were used: X-ray fluorescence spectrometry (XRF), inductively coupled plasma optical emission spectrometry (ICP-OES), atomic absorption spectrophotometry (AAS) and titrimetry. Boron and lithium were analysed by ICP OES, sodium and lithium by AAS, and boron by titrimetry, while the remaining frit elements and sodium were analysed by XRF.
The results found by the different methods were compared and each method was validated by means of reference materials. A procedure was established for preparing frit reference materials for calibrating and validating working methods on an industrial scale
Comportamiento de tejas de diferente color (rojo y paja) frente al biodeterioro
La colonización biológica es un fenómeno que afecta de forma negativa a la durabilidad de los materiales de construcción. A nivel industrial se ha observado que las tejas de color paja muestran mayor tendencia a la colonización biológica que las tejas de coloración rojiza, incluso cuando ambas presentan características similares. El objetivo de este trabajo es determinar la causa de las diferencias de biocolonización entre tejas de diferente color. Para ello, se ha determinado la composición química de la superficie de tejas de color paja y de color rojo mediante WD-FRX, la composición mineralógica por DRX, la microestructura de la superficie mediante MEB-EDX, la distribución del tamaño de poros mediante porosimetría de mercurio, y la solubilidad (Ca, Mg, Na, K, Cl and SO 2- por ICP-OES y cromatografía iónica).
Se ha evaluado la biorreceptividad midiendo la intensidad de fluorescencia con un fluorómetro, utilizando la cianobacteria Oscillatoria sp.
Los resultados muestran una mayor concentración de calcio y azufre, y una mayor solubilidad de éstos, en la superficie de las tejas paja, y éstas presentan una mayor tendencia a la colonización. Por lo tanto, el hecho de que presenten sales solubles en superficie favorece la biocolonización, y con ello, el deterioro estético y funcional del tejado.Biocolonization of building materials is a critical problem for the durability of constructions. Industrial experience shows that straw coloured roofing tiles are more prone to colonization than red roofing tiles, even having similar characteristics. The aim of this work is to explain the difference of biocolonization between different colour roofing tiles. The chemical composition of the surface of straw coloured and red roofing tiles, the phase composition and the microstructure of the roofing tiles were determined by WD-XRF, XRD and SEM-EDX, respectively. The pore size distribution was carried out by Hg porosimetry. The solubility was studied by determining the soluble salts (Ca, Mg, Na, K, Cl and SO 2-) by ICP-OES and ionic chromatography. Roofing tile bioreceptivity was evaluated by determining fluorescence intensity using a pulse-amplitude-modulated (PAM) fluorometer, and cyanobacteria Oscillatoria sp. The results obtained show higher concentration of calcium and sulphur in straw coloured roofing tiles surface, and higher solubility than red roofing tiles. Moreover, according to the results obtained in bioreceptivity assays, straw coloured roofing tiles are more prone to colonization than red roofing tiles, so, there is a relationship between surface properties of roofing tiles and biocolonization, as it is observed in industrial products
Comparative study of AR versus video tutorials for minor maintenance operations
[EN] Augmented Reality (AR) has become a mainstream technology in the development of solutions for repair and maintenance operations. Although most of the AR solutions are still limited to specific contexts in industry, some consumer electronics companies have started to offer pre-packaged AR solutions as alternative to video-based tutorials (VT) for minor maintenance operations. In this paper, we present a comparative study of the acquired knowledge and user perception achieved with AR and VT solutions in some maintenance tasks of IT equipment. The results indicate that both systems help users to acquire knowledge in various aspects of equipment maintenance. Although no statistically significant differences were found between AR and VT solutions, users scored higher on the AR version in all cases. Moreover, the users explicitly preferred the AR version when evaluating three different usability and satisfaction criteria. For the AR version, a strong and significant correlation was found between the satisfaction and the achieved knowledge. Since the AR solution achieved similar learning results with higher usability scores than the video-based tutorials, these results suggest that AR solutions are the most effective approach to substitute the typical paper-based instructions in consumer electronics.This work has been supported by Spanish MINECO and EU ERDF programs under grant RTI2018-098156-B-C55.Morillo, P.; García García, I.; Orduña, JM.; Fernández, M.; Juan, M. (2020). Comparative study of AR versus video tutorials for minor maintenance operations. Multimedia Tools and Applications. 79(11-12):7073-7100. https://doi.org/10.1007/s11042-019-08437-9S707371007911-12Ahn J, Williamson J, Gartrell M, Han R, Lv Q, Mishra S (2015) Supporting healthy grocery shopping via mobile augmented reality. 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Determinación de carbono orgánico en materias primas cerámicas en presencia de siderita, FeCO3
La materia orgánica es una de las impurezas presentes en las materias primas utilizadas en la fabricación de pavimentos y revestimientos cerámicos. Durante el proceso de cocción, el carbono orgánico (Corgánico) puede producir la aparición de un núcleo negro conocido como “corazón negro”, que puede causar defectos en el producto final.
Las materias primas cerámicas contienen Corgánico a nivel de mg·kg-1 (procedente de la materia orgánica) y carbono inorgánico (Cinorgánico) a nivel de porcentaje (procedente de siderita (FeCO3), calcita (CaCO3) y dolomita (CaMg(CO3)2), principalmente).
La presencia de siderita puede interferir en la determinación de Corgánico puesto que su temperatura de descomposición difiere muy poco de la temperatura de determinación del Corgánico, no ocurriendo lo mismo con la calcita y la dolomita, cuyas temperaturas de descomposición son superiores. Existen diversos métodos para la determinación de Corgánico en muestras sólidas, aunque no se han encontrado estudios cuantitativos sobre dicha determinación en presencia de siderita. En este trabajo se han desarrollado dos métodos para determinar Corgánico en materias primas y composiciones cerámicas mediante análisis elemental, en presencia de siderita, que pueden ser utilizados en el control de la aparición de corazón negro en baldosas cerámicas. La metodología desarrollada presenta bajos límites de cuantificación e incertidumbres, siendo un método rápido y preciso.Organic material is one of the impurities present in the raw materials used in the manufacture of ceramic floor and wall tiles. During the firing process, organic carbon (Corganic) can give rise to the appearance of what is known as "black core" inside the material, which can produce defects in the final product.
Ceramic raw materials contain Corganic in the order of mg•kg-1 (from organic material) and inorganic carbon (Cinorganic) in the order of a percentage (mainly from siderite – FeCO3, calcite – CaCO3, and dolomite – CaMg(CO3)2).
The presence of siderite can interfere in the determination of Corganic, since its decomposition temperature differs only slightly from the determination temperature of Corganic; this is not the case of calcite and dolomite, which decompose at higher temperatures. There are several different methods for determining Corganic in solid samples, although no quantitative studies on such determination in the presence of siderite were found. In this study two methods were developed for determining Corganic in raw materials and ceramic compositions by means of elemental analysis, in the presence of siderite, which can be used to control the appearance of black core in ceramic floor tiles. The method developed here offers low limits of quantification and uncertainties, while at the same time it is fast and precise
Nature s Top 100 Re-Revisited
"This is the peer reviewed version of the following article:
Martín-Martín, A., Ayllon, J. M., López-Cózar, E. D., & Orduna-Malea, E. (2015). Nature's top 100 Re-revisited. JASIST, 66(12), 2714., which has been published in final form at http://doi.org/10.1002/asi.23570. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."To mark the 50th anniversary of the Science Citation Index, Nature published a list of the 100 most-cited
papers of all time. It also included an alternative ranking from data provided by Google Scholar, which, as
this letter illustrates, contains certain inconsistencies. This does not, however, diminish the usefulness of
Google Scholar, not only in identifying the most-cited articles of all time, but also in reflecting the impact of
other document types (especially books), thus redefining the concept of academic impact.
Keywords:Martín-Martín, A.; Ayllón, JM.; Delgado López-Cózar, E.; Orduña Malea, E. (2015). Nature s Top 100 Re-Revisited. Journal of the American Society for Information Science and Technology. 66(12):2714-2714. doi:10.1002/asi.23570271427146612Bornmann , L. Nature's top 100 revisited. Journal of the Association for Information Science and Technology http://www.lutz-bornmann.de/icons/top_100.pdfGarfield , E. 2005 The agony and the ecstasy-the history and meaning of the Journal Impact Factor http://www.garfield.library.upenn.edu/papers/jifchicago2005.pdfMartin-Martin , A. Orduna-Malea , E. Ayllon , J.M. Delgado Lopez-Cozar , E. 2014 Does Google Scholar contain all highly cited documents (1950-2013)? http://arxiv.org/abs/1410.8464Van Noorden, R., Maher, B., & Nuzzo, R. (2014). The top 100 papers. Nature, 514(7524), 550-553. doi:10.1038/514550
The lost academic home: institutional affiliation links in Google Scholar Citations
This article is (c) Emerald Group Publishing and permission has been granted for this version to appear here (please insert the web address here). Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited[EN] Purpose - Google Scholar Citations (GSC) provides an institutional affiliation link which groups together authors who belong to the same institution. The purpose of this paper is to ascertain whether this feature is able to identify and normalize all the institutions entered by the authors, and whether it is able to assign all researchers to their own institution correctly.
Design/methodology/approach - Systematic queries to GSC's internal search box were performed under two different forms (institution name and institutional e-mail web domain) in September 2015. The whole Spanish academic system (82 institutions) was used as a test. Additionally, specific searches to companies (Google) and world-class universities were performed to identify and classify potential errors in the functioning of the feature.
Findings - Although the affiliation tool works well for most institutions, it is unable to detect all existing institutions in the database, and it is not always able to create a unique standardized entry for each institution. Additionally, it also fails to group all the authors who belong to the same institution. A wide variety of errors have been identified and classified.
Research limitations/implications - Even though the analyzed sample is good enough to empirically answer the research questions initially proposed, a more comprehensive study should be performed to calibrate the real volume of the errors.
Practical implications - The discovered affiliation link errors prevent institutions from being able to access the profiles of all their respective authors using the institutions lists offered by GSC. Additionally, it introduces a shortcoming in the navigation features of Google Scholar which may impair web user experience.
Social implications - Some institutions (mainly universities) are under-represented in the affiliation feature provided by GSC. This fact might jeopardize the visibility of institutions as well as the use of this feature in bibliometric or webometric analyses.
Originality/value - This work proves inconsistencies in the affiliation feature provided by GSC. A whole national university system is systematically analyzed and several queries have been used to reveal errors in its functioning. The completeness of the errors identified and the empirical data examined are the most exhaustive to date regarding this topic. Finally, some recommendations about how to correctly fill in the affiliation data (both for authors and institutions) and how to improve this feature are provided as well.Orduña Malea, E.; Ayllón, JM.; Martín-Martín, A.; Delgado-López-Cózar, E. (2017). The lost academic home: institutional affiliation links in Google Scholar Citations. Online Information Review. 41(6):762-781. doi:10.1108/OIR-10-2016-0302S76278141
Proceedings Scholar Metrics: H Index of proceedings on Computer Science, Electrical & Electronic Engineering, and Communications according to Google Scholar Metrics (2011-2015)
The objective of this report is to present a list of proceedings (conferences, workshops, symposia, meetings) in the areas of Computer Science, Electrical & Electronic Engineering, and Communications covered by Google Scholar Metrics and ranked according to their h-index. Google Scholar Metrics only displays publications that have published at least 100 papers and have received at least one citation in the last five years (2010-2014). The searches were conducted between the 7th and 12th of December, 2016. A total of 1634 proceedings have been identified.Martín-Martín, A.; Ayllón, JM.; Orduña Malea, E.; Delgado López-Cózar, E. (2016). Proceedings Scholar Metrics: H Index of proceedings on Computer Science, Electrical & Electronic Engineering, and Communications according to Google Scholar Metrics (2011-2015). http://hdl.handle.net/10251/11237
The silent fading of an academic search engine: the case of Microsoft Academic Search
Purpose - The purpose of this paper is to describe the obsolescence process of Microsoft Academic Search (MAS) as well as the effects of this decline in the coverage of disciplines and journals, and their influence in the representativeness of organizations.
Design/methodology/approach - The total number of records and those belonging to the most reputable journals (1,762) and organizations (346) according to the Field Rating indicator in each of the 15 fields and 204 sub-fields of MAS, have been collected and statistically analysed in March 2014, by means of an automated querying process via http, covering academic publications from 1700 to present.
Findings - MAS has no longer been updated since 2013, although this phenomenon began to be glimpsed in 2011, when its coverage plummeted. Throughout 2014, indexing of new records is still ongoing, but at a minimum rate, without following any apparent pattern.
Research limitations/implications - There are also retrospective records being indexed at present. In this sense, this research provides a picture of what MAS offered during March 2014 being queried directly via http.
Practical implications - The unnoticed obsolescence of MAS affects to the quality of the service offered to its users (both those who engage in scientific information seeking and also those who use it for quantitative purposes).
Social implications - The predominance of Google Scholar (GS) as monopoly in the academic search engines market as well as the prevalence of an open construction model (GS) vs a closed model (MAS).
Originality/value - A complete longitudinal analysis of disciplines, journals and organizations on MAS has been performed for the first time identifying an unnoticed obsolescence. Any public explanation or disclaimer note has been announced from the responsible company, something incomprehensible given its implications for the reliability and validity of bibliometric data provided on disciplines, journals, authors and congress as well as their fair representation on the academic search engine.This research was funded under Project HAR2011-30383-C02-02 from Direccion General de Investigacion y Gestion del Plan Nacional de I+D+I (Ministry of Economy and Competitiveness) and Project APOSTD/2013/002 from the Regional Ministry of Education, Culture and Sport (Generalitat Valenciana) in Spain.Orduña Malea, E.; Martín-Martín, A.; Ayllón, JM.; Delgado-López-Cózar, E. (2014). The silent fading of an academic search engine: the case of Microsoft Academic Search. Online Information Review. 38(7):936-953. https://doi.org/10.1108/OIR-07-2014-0169S936953387Beel, J. , Gipp, B. and Wilde, E. (2010), “Academic search engine optimization (ASEO)”, Journal of Scholarly Publishing, Vol. 41 No. 2, pp. 176-190.Butler, D. (2011), “Computing giants launch free science metrics: new Google and Microsoft services promise to democratize citation data”, Nature, Vol. 476 No. 7358, p.Carlson, S. (2006), “Challenging Google, Microsoft unveils a search tool for scholarly articles”, Chronicle of Higher Education, Vol. 52 No. 33, p.Delgado-López-Cózar, E., & Cabezas-Clavijo, Á. (2013). Ranking journals: could Google Scholar Metrics be an alternative to Journal Citation Reports and Scimago Journal Rank? Learned Publishing, 26(2), 101-113. doi:10.1087/20130206Delgado López-Cózar, E., Robinson-García, N., & Torres-Salinas, D. (2013). The Google scholar experiment: How to index false papers and manipulate bibliometric indicators. Journal of the Association for Information Science and Technology, 65(3), 446-454. doi:10.1002/asi.23056Haley, M. R. (2014). Ranking top economics and finance journals using Microsoft academic search versus Google scholar: How does the new publish or perish option compare? Journal of the Association for Information Science and Technology, 65(5), 1079-1084. doi:10.1002/asi.23080Haustein, S., Peters, I., Bar-Ilan, J., Priem, J., Shema, H., & Terliesner, J. (2014). Coverage and adoption of altmetrics sources in the bibliometric community. Scientometrics, 101(2), 1145-1163. doi:10.1007/s11192-013-1221-3Jacsó, P. (2005), “As we may search – comparison of major features of the Web of Science, Scopus, and Google Scholar”, Current Science, Vol. 89 No. 9, pp. 1537-1547.Jacsó, P. (2008). Google Scholar revisited. Online Information Review, 32(1), 102-114. doi:10.1108/14684520810866010Jacsó, P. (2011). The pros and cons of Microsoft Academic Search from a bibliometric perspective. Online Information Review, 35(6), 983-997. doi:10.1108/14684521111210788Jacsó, P. (2012). Google Scholar Metrics for Publications. Online Information Review, 36(4), 604-619. doi:10.1108/14684521211254121Khabsa, M. and Giles, C.L. (2014), “The number of scholarly documents on the public web”, PloS One, Vol. 9 No. 5, p.Labbé, C. (2010), “Ike Antkare one of the greatest stars in the scientific firmament”, ISSI Newsletter, Vol. 6 No. 1, pp. 48-52.Orduña-Malea, E., & Delgado López-Cózar, E. (2013). Google Scholar Metrics evolution: an analysis according to languages. Scientometrics, 98(3), 2353-2367. doi:10.1007/s11192-013-1164-8Ortega, J. L. (2014). Influence of co-authorship networks in the research impact: Ego network analyses from Microsoft Academic Search. Journal of Informetrics, 8(3), 728-737. doi:10.1016/j.joi.2014.07.001Ortega, J. L., & Aguillo, I. F. (2013). Institutional and country collaboration in an online service of scientific profiles: Google Scholar Citations. Journal of Informetrics, 7(2), 394-403. doi:10.1016/j.joi.2012.12.007Ortega, J. L., & Aguillo, I. F. (2014). Microsoft academic search and Google scholar citations: Comparative analysis of author profiles. Journal of the Association for Information Science and Technology, 65(6), 1149-1156. doi:10.1002/asi.23036Van Noorden, R. (2014). Online collaboration: Scientists and the social network. Nature, 512(7513), 126-129. doi:10.1038/512126
Masonry macro-block analysis
The structural analysis involves the definition of the model and selection of the analysis type. The model should represent the stiffness, the mass and the loads of the structure. The structures can be represented using simplified models, such as the lumped mass models, and advanced models resorting the Finite Element Method (FEM) and Discrete Element Method (DEM). Depending on the characteristics of the structure, different types of analysis can be used such as limit analysis, linear and non-linear static analysis and linear and non-linear dynamic analysis.
Unreinforced masonry structures present low tensile strength and the linear analyses seem to not be adequate for assessing their structural behaviour. On the other hand, the static and dynamic non-linear analyses are complex, since they involve large time computational requirements and advanced knowledge of the practitioner. The non-linear analysis requires advanced knowledge on the material properties, analysis tools and interpretation of results. The limit analysis with macro-blocks can be assumed as a more practical method in the estimation of maximum load capacity of structure. Furthermore, the limit analysis require a reduced number of parameters, which is an advantage for the assessment of ancient and historical masonry structures, due to the difficult in obtaining reliable data
Topology and excited state multiplicity as controlling factors in the carbazole-photosensitized CPD formation and repair
Photosensitized thyminethymine (ThyThy) formation and repair can be mediated by carbazole (Cbz). The former occurs from the Cbz triplet excited state via energy transfer, while the latter takes place from the singlet excited state via electron transfer. Here, fundamental insight is provided into the role of the topology and excited state multiplicity, as factors governing the balance between both processes. This has been achieved upon designing and synthesizing different isomers of trifunctional systems containing one Cbz and two Thy units covalently linked to the rigid skeleton of the natural deoxycholic acid. The results shown here prove that the Cbz photosensitized dimerization is not counterbalanced by repair when the latter, instead of operating through-space, has to proceed through-bond. © 2022 The Authors. Published by American Chemical Society
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