1,721,061 research outputs found
Understanding the topography effects on competitive adsorption on a nanosized anatase crystal: a molecular dynamics study
No full textUsing Molecular Mechanics and Molecular Dynamics methods, we investigated at the atomistic level the topography effects both on physisorption on different crystalline planes of TiO2 anatase and on the competitive adsorption when three different crystallographic faces were simultaneously present in an idealized nanosized crystal interacting with a simple heteroaromatic molecule experimentally used in sunlight-induced photosynthetic reaction
Adsorbent sponges from TEMPO-oxidized cellulose cross-linked with branched-PEI for water remediation
No full textA new class of cellular solids with macro and micro porosity have been synthesized by the combination of cellulose nanofibers from TEMPO-NaClO mediated oxidation (TOCNF) [1] and branched polyethyleneimine, via formation of amide-bonds (TOCNF-bPEI copolymer). The sponge-like materials obtained in this way have chelating amino groups as basic sites in the nano-porous structure, showing high performances in removing heavy metal ions and phenolic pollutants from contaminated water
Melanin-coating as a versatile entry to functionalized cellulose aerogels: synthesis, structure, properties.
No full textA two-step approach consisting of the NaClO/TEMPO mediated oxidation of cellulose, followed by a freeze-drying procedure, led to the production of white carboxylated cellulose nanofibre (CNF) aerogels (a) [1]. By means of an ad hoc protocol, involving alkali-induced oxidative polymerization of 5,6-dihydroxyindole (DHI) [2] on the CNF aerogel, the efficient deposition of melanin polymer onto the aerogel leading to a black coating (b) could be achieved. Preliminary characterization of the melanized aerogels (Mel-CNF) by SEM microscopy confirmed the high degree of porosity of the original aerogel with no apparent bulk polymerization (c). Possible applications of the newly developed Mel-CNF material will be discussed based on a systematic characterization of its adsorption, paramagnetic and free-radical scavenging properties
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
N-Hydroxyphthalimide (NHPI)-Organocatalyzed Aerobic Oxidations: Advantages, Limits, and Industrial Perspectives
Full text linkN-Hydroxyphthalimide (NHPI) is an efficient organocatalyst, capable of promoting
free-radical processes via hydrogen atom transfer (HAT) reactions.
The first catalytic use of NHPI was reported in 1977 by Grochowski and coworkers
for the addition of ethers to diethyl azodicarboxylate and the oxidation of
2-propanol to acetone [1]....
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
Photocatalytic Minisci reaction: A promising and eco-friendly route to functionalize heteroaromatics of biological interest.
No full textDispelling 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
- …
