1,721,238 research outputs found
The Spectrophotometric Determination of αβ-Unsaturated Aldehydes and Ketones with Girard-T Reagent
No full textAbstract
A rapid spectrophotometric method is suggested for the determination of ethisterone and of methyltestosterone in tablets by reaction with Girard-T reagent.</jats:p
The Spectrophotometric Determination of αβ-Unsaturated Aldehydes and Ketones With Girard-T Reagent
No full textAbstract
Spectrophotometric methods for the determination of citral, cinnamaldehyde and carvone in essential oils using Girard-T reagent are described. The results are compared with those obtained by the hydroxylamine hydrochloride method.</jats:p
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
Reduction of Zygomatic Fractures Using the Carroll-Girard T-bar Screw
Get PDFZygomatic fractures are the second most common facial bone fractures encountered and treated by plastic surgeons. Stable fixation of fractured fragments after adequate exposure is critical for ensuring three-dimensional anatomic reduction. Between January 2008 and December 2010, 17 patients with zygomatic fractures were admitted to our hospital; there were 15 male and 2 female patients. The average age of the patients was 41 years (range, 19 to 75 years). We exposed the inferior orbital rim and zygomatic complex through a lateral brow, intraoral, and subciliary incisions, which allowed for visualization of the bone, and then the fractured parts were corrected using the Carroll-Girard T-bar screw. Postoperative complications such as malar asymmetry, diplopia, enophthalmos, and postoperative infection were not observed. Lower eyelid retraction and temporary ectropion occurred in 1 of the 17 patients. Functional and cosmetic results were excellent in nearly all of the cases. In this report, we describe using the Carroll-Girard T-bar screw for the reduction of zygomatic fractures. Because this instrument is easy to use and can rotate to any direction and vector, it can be used to correct displaced zygomatic bone more accurately and safely than other devices, without leaving facial scars
SINTEZA, STRUCTURA ŞI PROPRIETĂŢILE MAGNETICE ALE COMPUŞILOR COORDINATIVI AI FIERULUI CU DERIVAŢII REACTIVULUI GIRARD T
No full textLa condensarea reactivului Girard T cu aldehida 5-bromsalicilică se formează o hidrazonă nouă [H2(5BrSalGT)]Cl. Acest ligand tridentat este solubil în apă şi reacţionează cu ionii de fier cu formarea compusului coordinativ [FeLCl2], care interacţionează în soluţii apoase cu ionul azid N3- şi rezultă produşii [FeL(N3)2]2 (1) şi [Fe(L)2]N3.6H2O (2). Analiza cu raxe X pentru 1 şi 2 relatează că în procesul de coordinare ligandul se deprotonează şi se coordinează la metal în formă monoanionică. Proprietăţile magnetice ale compuşilor 1 şi 2 demonstrează un comportament paramagnetic funcţie de temperatură.SYNTHESIS, STRUCTURE AND MAGNETIC PROPERTIES OF IRON COORDINATION COMPOUNDS WITH GIRARD T REAGENTThe condensation of 5-bromosalicylaldehyde with Girard’s T reagent yields a new hydrazone [H2(5BrSalGT)]Cl. This tridentate ligand is soluble in water and react with iron ions with the formation of coordination compound [FeLCl2]. In water solutions [FeLCl2] interact with azide ion N3- allowing the formation of [FeL(N3)2]2 (1) and [Fe(L)2]N3.6H2O (2) compounds. The crystallographic studies of 1 and 2 show that in the coordination process the ligand is deprotonated and coordinate to the metal as monoanion. The cryomagnetic studies of 1 and 2 show a paramagnetic behaviour.</p
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
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