Results 251 to 260 of about 275,044 (284)

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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Topological Index and Analytical Index: Reformulation of Index Theory

2019
In this part we present the main algebraic structures on topological manifolds and we reformulate the index theory.
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Index Theorems and Noncommutative Topology

2008
These lecture notes are mainly devoted to a K-theory proof of the Atiyah-Singer index theorem. Some applications of the K-theory to noncommutative topology are also given.
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The Sum of a Topological Index and Its Reciprocal Index

Match Communications in Mathematical and in Computer Chemistry
Summary: Let \(G\) be a simple connected graph. For a vertex-degree-based topological index \(TI_f(G) = \sum\limits_{uv\in E(G)}f(d_u, d_v)\), where \(f(x, y)\) is a pertinently chosen symmetric real function, the topological index \(RTI_f(G) = \sum\limits_{uv\in E(G)}\frac{1}{f(d_u, d_v)}\) is called the reciprocal index of \(TI_f\).
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Highly discriminating distance-based topological index

Chemical Physics Letters, 1982
Abstract A new topological index J (based on distance sums s i as graph invariants) is proposed. For unsaturated or aromatic compounds, fractional bond orders are used in calculating s i . The degeneracy of J is lowest among all single topological indices described so far. The asymptotic behaviour of J is discussed, e.g. when n → ∞ in C n
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Weyl, Dirac and high-fold chiral fermions in topological quantum matter

Nature Reviews Materials, 2021
M Zahid Hasan, Guoqing Chang, Ilya Belopolski   +2 more
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