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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
Kinetics of base hydrolysis of (nitrato)pentaamminecobalt(III): stability and reactivity of its ion pairs with perchlorate and azide
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Structure and Properties of the Precursor/Successor Complex and Transition State of the CrCl2+/Cr2+ Electron Self-Exchange Reaction via the Inner-Sphere Pathway
No full textThe electron self-exchange reaction CrCl(OH2)5(2+) + Cr(OH2)6(2+) -> Cr(OH2)(6)(2+) + CrCl(OH2)(5)(2+), proceeding via the inner-sphere pathway, was investigated with quantum-chemical methods. Geometry and vibrational frequencies of the precursor/successor (P/S) complex, (H2O)5Cr(III)ClCr(II)(OH2)(5)(4+)/(H2O)(5)(CrClCrIII)-Cl-II(OH2)5(4+), and the transition state (TS), (H2O)(5)CrClCr(OH2)5(4+) double dagger, were computed with density functional theory (DFT) and conductor polarizable continuum model hydration. Consistent data were obtained solely with long-range-corrected functionals, whereby in this study, LC-BOP was used. Bent and linear structures were computed for the TS and P/S. The electronic coupling matrix element (H-ab) and the reorganizational energy (lambda) were calculated with multistate extended general multiconfiguration quasi-degenerate second-order perturbation theory. The nuclear tunneling factor (Gamma(n)), the nuclear frequency factor (nu(n)), the electronic frequency factor (nu(el)), the electron transmission coefficient (k(el)), and the first-order rate constant (ket) for the electron-transfer step (the conversion of the precursor complex into the successor complex) were calculated based on the imaginary frequency (nu double dagger) of the TS, the Gibbs activation energy (Delta G double dagger), H-ab, and lambda. The formation of the precursor complex via water substitution at Cr(OH2)(6)(2+) was also investigated with DFT and found to be very fast. Thus, the electron-transfer step is rate-determining. For the substitution reaction, only a bent TS structure could be obtained. The overall rate constant (k) was estimated as the product K-Akev, whereby KA is the equilibrium constant for the formation of the ion aggregate of the reactants Cr(OH2)(6)(2+) and CrCl(OH2)(5)(2+), Cr(H2O)(6).CrCl(OH2)(5)(4+) (IAR). k calculated for the bent and linear isomers agrees with the experimental value.LP
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
Base hydrolysis of pentaammine complexes of cobalt(III): structure, reactivity, and lifetime of the intermediates
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Aquation of the Chloro Pentaammine Complexes of Cobalt(III) and Chromium(III): Do the Almost Equal Activation Parameters Arise from a Common Mechanism?
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Attribution of water-exchange mechanism of transition metal hexaaqua ions using quantum chemical methods
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Mechanism of Water Exchange for the Di- and Trivalent Metal Hexaaqua Ions of the First Transition Series
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