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1.
Chitosan microspheres containing bromocresol green, cresol red, and phenolphthalein for corrosion detection, through pH change, are synthesized in order to be used in protective coatings for aluminium alloys. Microspheres containing corrosion detection species are characterized morphologically (SEM) and physico‐chemically (FTIR, TGA). Release studies (UV–vis) are performed in corrosion‐promoting conditions (pH, NaCl), and detection studies by immersion in media associated with corrosion activity while microspheres' sensing activity is evaluated visually. Electrochemical characterization of AA2024 substrates in the presence of chitosan spheres is performed to understand material performance, and a color change is observed as a result of local pH increase in cathodic areas when corrosion takes place. These findings can be correlated with the results from release studies and seem a promising approach for corrosion sensing purposes, not only because pH increase is possible to detect due to corrosion, but also because chitosan is considered an environmentally friendly material. 相似文献
2.
In this paper we investigate the position of a review network within a research specialty; the network of scholars who write
reviews of their colleagues’ work. This is one of the voluntary activities that researchers perform as a prerequisite for
the functioning of the invisible college. We compare this network to other networks within the specialty, and this allows
us to distinguish various roles: stars, influentials, members, reviewers and juniors. As scholars are characterized by different role-configurations, the invisible college becomes stratified. We discuss the
implications for the development of a referee factor and review factor, norms for refereeing and reviewing, and the development
of systems-based research evaluations. 相似文献
3.
University web sites play an important role in facilitating a wide range of types of communication. This paper reports an
analysis of international academic linking in Europe, with particular reference to European Union (EU) integration. The Microsoft
search service was used to calculate international interlinking to universities and from universities. Four different web
topologies were found for the link structure data and poorly connected countries were identified. The results show the expected
EU dominance of the large richer Western European nations, particularly the UK and Germany. The new EU countries are not yet
integrated into the EU web but some show strong regional connections. 相似文献
4.
Alesia Zuccala 《Scientometrics》2010,84(1):221-235
This paper revisits an aspect of citation theory (i.e., citer motivation) with respect to the Mathematical Review system and
the reviewer’s role in mathematics. We focus on a set of journal articles (369) published in Singularity Theory (1974–2003),
the mathematicians who wrote editorial reviews for these articles, and the number of citations each reviewed article received
within a 5 year period. Our research hypothesis is that the cognitive authority of a high status reviewer plays a positive
role in how well a new article is received and cited by others. Bibliometric evidence points to the contrary: Singularity
Theorists of lower status (junior researchers) have reviewed slightly more well-cited articles (2–5 citations, excluding author
self-citations) than their higher status counterparts (senior researchers). One explanation for this result is that lower
status researchers may have been asked to review ‘trendy’ or more accessible parts of mathematics, which are easier to use
and cite. We offer further explanations and discuss a number of implications for a theory of citation in mathematics. This
research opens the door for comparisons to other editorial review systems, such as book reviews written in the social sciences
or humanities. 相似文献
5.
Kulczycki Emanuel Engels Tim C. E. Pölönen Janne Bruun Kasper Dušková Marta Guns Raf Nowotniak Robert Petr Michal Sivertsen Gunnar Istenič Starčič Andreja Zuccala Alesia 《Scientometrics》2018,115(1):463-486
Scientometrics - The increasing number of open-access full-text scientific documents promotes the transformation from metadata- to content-based studies, which is more detailed and semantic. Along... 相似文献
6.
This study examined 148 Asian American and European American late adolescents' perceptions of differential affection and control by mothers and fathers as predictors of academic achievement and self-perceptions of intellectual ability and global self-worth. Overall, analyses generally confirmed the hypotheses that the more differentially favorable the treatment (more affection or less control) or the less differential treatment (above and beyond which sibling was favored) reported in the home, the more positive late adolescents' outcomes. Perceptions of differential parental treatment predicted up to 13% of the variance in achievement and self-perceptions. Several findings were moderated by ethnicity or gender. Finally, and perhaps most importantly, perceptions of differential parental treatment predicted a significant and unique amount of variance in outcomes beyond that predicted by perceptions of absolute levels of affection and control. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Application of Room‐Temperature Aprotic and Protic Ionic Liquids for Oxidative Folding of Cysteine‐Rich Peptides 下载免费PDF全文
Pascal Heimer Dr. Alesia A. Tietze Miriam Böhm Dr. Ralf Giernoth Andrea Kuchenbuch Dr. Annegret Stark Dr. Enrico Leipold Prof. Dr. Stefan H. Heinemann Dr. Christian Kandt Prof. Dr. Diana Imhof 《Chembiochem : a European journal of chemical biology》2014,15(18):2754-2765
The oxidation of the conotoxin μ‐SIIIA in different ionic liquids was investigated, and the results were compared with those obtained in [C2mim][OAc]. Conversion of the reduced precursor into the oxidized product was observed in the protic ILs methyl‐ and ethylammonium formate (MAF and EAf, respectively), whereas choline dihydrogenphosphate and Ammoeng 110 failed to yield folded peptide. However, the quality and yield of the peptide obtained in MAF and EAF were lower than in the case of the product from [C2mim][OAc]. Reaction conditions (temperature, water content) also had an impact on peptide conversion. A closer look at the activities of μ‐SIIIA versions derived from an up‐scaled synthesis in [C2mim][OAc] revealed a significant loss of the effect on ion channel NaV1.4 relative to the buffer‐oxidized peptide, whereas digestion of either μ‐SIIIA product by trypsin was unaffected. This was attributed to adherence of ions from the IL to the peptide, because the disulfide connectivity is basically the same for the differentially oxidized μ‐SIIIA versions. 相似文献
8.
Although the writing of a thesis is a very important step for scientists undertaking a career in research, little information
exists on the impact of theses as a source of scientific information. Knowing the impact of theses is relevant not only for
students undertaking graduate studies, but also for the building of repositories of electronic theses and dissertations (ETD)
and the substantial investment this involves. This paper shows that the impact of theses as information sources has been generally
declining over the last century, apart from during the period of the ‘golden years’ of research, 1945 to 1975. There is no
evidence of ETDs having a positive impact; on the contrary, since their introduction the impact of theses has actually declined
more rapidly. This raises questions about the justification for ETDs and the appropriateness of writing monograph style theses
as opposed to publication of a series of peer-reviewed papers as the requirement for fulfilment of graduate studies. 相似文献
9.
The initial growth stages of materials non-active to a substrate has been extensively studied for decades, whereas there had been fewer studies on the initial growth of active metals on silicon substrate, despite its technological importance. In this paper the very early growth stages of transition metal (Ti, V and Nb) films deposited by rf sputtering on unheated (100) Si substrate were studied by in situ X-ray photoelectron spectroscopy. The following sequence of the phase composition and the growth mechanism changes during deposition process was revealed. Initially in a submonolayer regime, small 3D TiO2 islands are formed via reduction of a native silicon oxide layer on a substrate followed by formation of a TiO phase between TiO2 islands and on their top. After deposition of ca. 2 monolayers a metallic Ti phase appears and later only the metal Ti film grows. The same growth behavior takes place at Nb and V deposition with a difference that in the case of Nb the above changes occur at earlier stages what can be explained by the highest niobium activity to the reduction of silicon oxide in the row V, Nb, Ti. 相似文献
10.
M. N. Levin G. V. Semenova T. P. Sushkova É. A. Dolgopolova V. V. Postnikov 《Technical Physics Letters》2002,28(10):818-820
Experiments on InAs crystals demonstrate that exposure to pulsed magnetic fields can increase the phase homogeneity and structural perfection of the binary phases of AIIIBV semiconductor compounds. 相似文献