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Fixed-Order Chemical Trees with Given Segments and Their Maximum Multiplicative Sum Zagreb Index
MathematicsTopological indices are often used to predict the physicochemical properties of molecules. The multiplicative sum Zagreb index is one of the multiplicative versions of the Zagreb indices, which belong to the class of most-examined topological indices ...
Akbar Ali +4 more
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The inverse Wiener polarity index problem for chemical trees [PDF]
PLoS One, 2018 The Wiener polarity number (which, nowadays, known as the Wiener polarity index and usually denoted by Wp) was devised by the chemist Harold Wiener, for predicting the boiling points of alkanes.
Z. Du, Akbar Ali
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Equienergetic chemical trees [PDF]
Journal of the Serbian Chemical Society, 2004 The energy E(G) of a graph G is the sum of the absolute values of the eigenvalues of G. Two graphs, G 1 and G 2, are said to be equienergetic if E(G 1) = E(G 2).We report here the results of the search for pairs of equienergetic acyclic molecular graphs (
Brankov Vladimir +2 more
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Exponential second Zagreb index of chemical trees [PDF]
Transactions on Combinatorics, 2021 Cruz, Monsalve and Rada [Extremal values of vertex-degree-based topological indices of chemical trees, Appl. Math. Comput. 380 (2020) 125281] posed an open problem to find the maximum value of the exponential second Zagreb index for chemical ...
Selvaraj Balachandran, Tomas Vetrik
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Equiseparable chemical trees [PDF]
Journal of the Serbian Chemical Society, 2003 Let n1(e|T) and n2(e|T) denote the number of vertices of a tree T, lying on the two sides of the edge e. Let T1 and T2 be two trees with equal number of vertices, let e be an edge of T1 and f an edge of T2.
BORIS FURTULA +2 more
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Zeitschrift Fur Naturforschung - Section A Journal of Physical Sciences, 2002 Avariety of molecular-graph-based structure-descriptors were proposed, in particular the Wiener index W, the largest graph eigenvalue λ1, the connectivity index χ, the graph energy E and the Hosoya index Z, capable of measuring the branching of the ...
Dieter Rautenbach +2 more
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Two Degree Distance Based Topological Indices of Chemical Trees
IEEE Access, 2019 Let G = (VG, EG) be a simple and connected graph. The eccentric connectivity index of G is represented as ξc(G) = Σx∈VG degG(x)ecG(x), where degG(x) and ecG(x) represent the degree and the eccentricity of x, respectively.
Shehnaz Akhter
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Extrafloral Nectaries in Woody Plants: Toward an Integrated Framework for Ant-Mediated Plant Defense [PDF]
PlantsExtrafloral nectaries (EFNs)—secretory structures that recruit predatory arthropods as indirect defenders against herbivory—have been studied almost exclusively in herbaceous systems, leaving a critical gap in our understanding of plant defense in woody ...
Fangming Liu +3 more
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Hyper-Wiener index and Laplacian spectrum [PDF]
Journal of the Serbian Chemical Society, 2003 The hyper-Wiener index WWW of a chemical tree T is defined as the sum of the product n1 n2 n3, over all pairs υ,ν of vertices of T, where n1 and n2 are the number of vertices of T, lying on the two sides of the path which connects υ and ν, and n3 is the ...
Gutman Ivan
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On the Sombor index of chemical trees
, 2021 Molecular descriptors are mathematical values used in evaluation and prediction of properties of chemical compounds. They are used to describe the structure and shape of molecules of even more not yet synthesized compounds and so play significant role in
Zana Kovijanic-Vukicevic
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