Results 1 to 10 of about 527,105 (289)
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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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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Generation, Ranking and Unranking of Ordered Trees with Degree Bounds [PDF]
Electronic Proceedings in Theoretical Computer Science, 2016 We study the problem of generating, ranking and unranking of unlabeled ordered trees whose nodes have maximum degree of Δ. This class of trees represents a generalization of chemical trees. A chemical tree is an unlabeled tree in which no node has degree
Mahdi Amani, Abbas Nowzari-Dalini
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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.
Zhibin Du, Akbar Ali
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Chemical “pruning” of walnut trees
California Agriculture, 1980 A chemical pinching agent sprayed on young walnut trees in the spring reduced terminal growth and increased branching, producing a response similar to that obtained by pruning.
G Martin +3 more
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Chemical defoliation of fruit trees
California Agriculture, 1977 Trees in most mature peach, nectarine, and plum orchards in the southern San Joaquin Valley cease growth by early to mid-October. Because the foliage often persists on the trees for another three to five weeks and interferes with the pruner's vision, it ...
M Gerdts, G Obenauf, J LaRue, G Leavitt
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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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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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Synthesis of Terpineol from Alpha-Pinene Catalyzed by α-Hydroxy Acids
Molecules, 2022 We report the use of five alpha-hydroxy acids (citric, tartaric, mandelic, lactic and glycolic acids) as catalysts in the synthesis of terpineol from alpha-pinene.
Zhong-Lei Meng +5 more
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Molecules, 2023 This study examined the preparation of isobornyl acetate/isoborneol from camphene using an α-hydroxyl carboxylic acid (HCA) composite catalyst. Through the study of the influencing factors, it was found that HCA and boric acid exhibited significant ...
Zhong-Lei Meng +7 more
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