Results 291 to 300 of about 272,456 (331)

A Novel Quantum-Topology Index

Journal of Chemical Information and Computer Sciences, 2000
By modifying the delta values of molecular connectivity indexes, new quantum-topology descriptors are presented in this paper. Their ability to describe molecular structure, both geometric and electronic, is established by correlating them with the bonding energy (E), force constant (kappa), and radius (R) of a heterogeneous set of monohydrides, as ...
, Li, , Yu, , Zhu
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A forgotten topological index

Journal of Mathematical Chemistry, 2015
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Furtula, Boris, Gutman, Ivan
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A Z2-topological index as a Z2-state index

Journal of Mathematical Physics, 2022
Within the setting of infinite-dimensional self-dual CAR C* algebras describing fermions in the Zd lattice, we depart from the well-known Araki–Evans σ(P1,P2)Z2 index for quasi-free fermion states and rewrite it in terms of states rather than in terms of basis projections.
N. J. B. Aza, L. C. P. A. M. Müssnich, A. F. Reyes-Lega   +2 more
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On reciprocal molecular topological index

Journal of Mathematical Chemistry, 2007
We report some properties of the reciprocal molecular topological index RMTI of a connected graph, and, in particular, its relationship with the first Zagreb index M-1. We also derive the upper bounds for RMTI in terms of the number of vertices and the number of edges for various classes of graphs, including Kr+1 -free graphs with r >= 2, quadrangle ...
Zhou, Bo, Trinajstić, Nenad
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Topological symmetry identification of kinematic chains based on topological index

Mechanism and Machine Theory, 2020
Abstract To improve the synthesis efficiency of kinematic chains (KCs) and mechanisms, the topological symmetry of a chain should be considered. However, the symmetry recognition of pairs is rarely mentioned. Therefore, an index, called the extended adjacency identification index for the symmetry of KCs (SKC-EAID), is proposed to identify the ...
Tao Deng, Hui Xu, Changjun Wu, Lu Zhang, Zhihan Gan   +4 more
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Extension of a Highly Discriminating Topological Index

Journal of Chemical Information and Modeling, 2015
A highly discriminating topological index, EAID, is generated in our laboratory. A systematic search for degeneracy was performed on a total of over 14 million structures, and no duplicate occurred. These structures are as follows: over 3.8 million alkane trees with 1-22 carbon atoms; over 0.38 million structures containing heteroatoms; over 4 million ...
Qingyou, Zhang, Chengcheng, Wu, Fangfang, Zheng, Tanfeng, Zhao, Yanmei, Zhou, Lu, Xu   +5 more
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On Hall and Kier's Topological State and Total Topological Index

Journal of Chemical Information and Computer Sciences, 1994
The topological state and the total topological index, tau, have been tested systematically. Counterexamples are provided proving that the topological state method cannot determine classes of symmetrically equivalent atoms in a molecule fully correct ...
Chang-Yu Hu, Lu Xu
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On the forgotten topological index

2017
Summary: The forgotten topological index of a graph \(G\) is defined as \(F(G)=\sum_{u\in V(G)}d(u)^3\). In this paper, we compute some properties of forgotten index and then, we determine it for some classes of product graphs.
Ghorbani, M., Khaksari, A.
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Forgotten reduced neighborhood topological index

Asian-European Journal of Mathematics
Topological graph indices are the most important applications of graph theory. In the last few decades, such applications have been increasingly in use for mathematicians, chemists, pharmacologists. Due to these applications, a large number of these indices are defined and used in several areas.
Anwar Saleh, G. B. Sophia Shalini, Ismail Naci Cangul   +2 more
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“Topologically Indexed Function Spaces and Adjoint Functors”

Canadian Mathematical Bulletin, 1982
AbstractLet Top denote the category of topological spaces and continuous maps. In this paper we discuss families of function spaces indexed by the elements of a topological space T, and their relationship to the characterization of right adjoints Top/S → Top/T, where S is also a topological space. After reducing the problem to the case where S is a one-
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