Results 261 to 270 of about 11,756,121 (296)

The Average Wiener Index of Trees and Chemical Trees

Journal of Chemical Information and Computer Sciences, 1999
Meir and Moon (J. Combin. Theory 1970, 8, 99−103) reported a combinatorial formula for the average value of the distance between a pair of vertices in the class of all labeled trees with a fixed number (= n) of vertices. From this result an expression for the average Wiener index 〈Wn〉lab of labeled n-vertex trees follows immediately.
A. Dobrynin, I. Gutman
semanticscholar   +3 more sources

The Estrada index of chemical trees

Journal of Mathematical Chemistry, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Aleksandar Ilić, D. Stevanović
semanticscholar   +3 more sources

The minimum ABC index of chemical trees

Discrete Applied Mathematics
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Wei Gao
exaly   +3 more sources

Counting Chemical Structures Resembling Trees

2018 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2018
Trees have been used for counting chemical structures of non-isomorphic forms. Graph enumeration can be either isomorphic or non-isomorphic. Isomorphic tree enumeration arises in the context of listing all isomorphic subtrees of a given graph whereas non-isomorphic enumeration lists all unique trees that satisfy given constraints. We study the chemical
Athira Selvam, Sravya K. V. S. P. Sai, Bhadrachalam Chitturi   +2 more
openaire   +2 more sources

Mining environmental chemicals with boosted trees

Proceedings of the 35th Annual ACM Symposium on Applied Computing, 2020
In response to scientific reports and legislative actions, the United States Environmental Protection Agency (EPA) launched an Endocrine Disruptor Screening Program (EDSP). The overarching aim of this program is to develop novel analytical and computational tools and methods for the detection of environmental chemicals causing aberrations in estrogen ...
openaire   +2 more sources

TECHNIQUES FOR INJECTING CHEMICALS INTO TREES

Arboricultural Journal, 1985
Summary Many existing techniques for applying solutions to woody plants are inexact, or require expensive apparatus and specialised training to use. Simple, cheap, and accurate methods are described for injecting volumes from 1 μ1 to 100 ml into main stems or branches of 5 mm diameter upwards.
J McP Dick, K A Longman
openaire   +1 more source

Chemical Trees with Maximal VDB Topological Indices

match Communications in Mathematical and in Computer Chemistry, 2023
Summary: A general vertex-degree-based (VDB) topological index of a graph \(G\) is defined as \[ \mathcal{T}_f=\mathcal{T}_f(G)=\sum_{uv\in E(G)}f(d_G(u),d_G(v)), \] where \(f(x,y)>0\) is a symmetric real function with \(x\ge 1\) and \(y\ge 1\).
openaire   +2 more sources

On Randić indices of chemical trees and chemical unicyclic graphs [PDF]

MATCH : communications in mathematical and in computer chemistry, 2009
The fourth maximum Randić indices for the n-vertex chemical trees for n /10 and n-vertex chemical unicyclic graphs for n / 7 are determined, respectively.
Du, Zhibin, Zhou, Bo, Trinajstic, Nenad
openaire   +2 more sources

Phytotoxicity of Pheromonal Chemicals to Fruit Tree Foliage: Chemical and Physiological Characterization

Journal of Economic Entomology, 2001
Some recent high-load, low-density pheromone-release devices emit an ethanolic blend of pheromone directly onto crop foliage to control insect pests by mating disruption. This study characterized the phytotoxicity associated with deposition of some pheromonal compounds in concentrated drops on the foliage of trees bearing aerosol release devices.
P Y, Giroux, J R, Miller
openaire   +2 more sources

Chemical Interactions between Cloud Droplets and Trees

1988
The chemical composition of both liquid droplet and leaf surface determines the behaviour of a cloud droplet on interception by vegetation. In some circumstances, particularly in wind-driven cloud, droplets may not adhere to foliage. Once on the leaf surface, the contact angle between the droplet and surface will determine the amount of water held by ...
openaire   +2 more sources