scholarly journals General (α,2)-Path Sum-Connectivirty Indices of One Important Class of Polycyclic Aromatic Hydrocarbons

Symmetry ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 426
Author(s):  
Haiying Wang
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Real Number ◽  
Aromatic Hydrocarbons ◽  
Molecular Graph ◽  
Three Dimensional ◽  
3D Qsar ◽  
Important Class ◽  
Polycyclic Aromatic ◽  
T Path ◽  
Extremal Values

The general ( α , t ) -path sum-connectivity index of a molecular graph originates from many practical problems, such as the three-dimensional quantitative structure–activity relationships (3D QSAR) and molecular chirality. For arbitrary nonzero real number α and arbitrary positive integer t, it is defined as t χ α ( G ) = ∑ P t = v i 1 v i 2 ⋯ v i t + 1 ⊆ G [ d G ( v i 1 ) d G ( v i 2 ) ⋯ d G ( v i t + 1 ) ] α , where we take the sum over all possible paths of length t of G and two paths v i 1 v i 2 ⋯ v i t + 1 and v i t + 1 ⋯ v i 2 v i 1 are considered to be one path. In this work, one important class of polycyclic aromatic hydrocarbons and their structures are firstly considered, which play a role in organic materials and medical sciences. We try to compute the exact general ( α , 2 ) -path sum-connectivity indices of these hydrocarbon systems. Furthermore, we exactly derive the monotonicity and the extremal values of these polycyclic aromatic hydrocarbons for any real number α . These valuable results could produce strong guiding significance to these applied sciences.

scholarly journals The General (α,3)-Path Connectivity Indices of Polycyclic Aromatic Hydrocarbons

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Haiying Wang ◽  
Chuantao Li
Keyword(s):  
Applied Sciences ◽  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Molecular Graph ◽  
Three Dimensional ◽  
3D Qsar ◽  
Medical Sciences ◽  
Connectivity Indices ◽  
Polycyclic Aromatic ◽  
Extremal Values

The general (α,t)-path connectivity index of a molecular graph originates from many practical problems such as three-dimensional quantitative structure-activity (3D QSAR) and molecular chirality. It is defined as Rtα(G)=∑Pt=vi1vi2⋯vit+1⊆G[d(vi1)d(vi2)⋯d(vit+1)]α, where the summation is taken over all possible paths of length t of G and we do not distinguish between the paths vi1vi2⋯vit+1 and vit+1⋯vi2vi1. In this paper, we focus on the structures of Polycyclic Aromatic Hydrocarbons (PAHn), which play a role in organic materials and medical sciences. We try to compute the exact general (α,3)-path connectivity indices of this family of hydrocarbon structures. Furthermore, we exactly derive the monotonicity and the extremal values of R3α(PAHn) for any real number α. These valuable results could produce strong guiding significance to these applied sciences.

Three-Dimensional Flamelet Simulation of Polycyclic Aromatic Hydrocarbons Formation in DI-Diesel Engines

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Beijing Zhong ◽  
Shuai Dang ◽  
Jun Xi
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Numerical Simulations ◽  
Aromatic Hydrocarbons ◽  
Direct Injection ◽  
Combustion Process ◽  
Three Dimensional ◽  
Kinetic Mechanism ◽  
Flamelet Model ◽  
Polycyclic Aromatic ◽  
Reduced Kinetic Mechanism

In this study, numerical simulations for an n-heptane fueled Chaochai 6102bzl direct injection diesel engine are performed in order to predict the chemical details of the combustion process and resulting polycyclic aromatic hydrocarbons (such as benzene, naphthalene, phenanthrene and pyrene) formation. The diesel geometry and reduced kinetic mechanism of n-heptane oxidation, which includes only 86 reactions and 57 species, have been developed and incorporated into the computational fluid dynamics code, FLUENT. The diesel unsteady laminar flamelet model, turbulence model and spray model have been employed in the numerical simulations. The numerical simulation results showed that the polycyclic aromatic hydrocarbons were firstly increased with the increase of diesel crank angel and then decreased, which was mostly located at the bottom of diesel combustion chamber wall.

Computing Analysis of Degree and Connection Based Irregular Indices of Polycyclic Aromatic Hydrocarbons

2021 ◽  
Vol 18 ◽  
Author(s):  
Muhammad Javaid ◽  
Muhammad Ibraheem ◽  
Abdul Raheem
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Topological Index ◽  
Medical Science ◽  
Molecular Graph ◽  
Chemical Compounds ◽  
Molecular Graphs ◽  
Equal Degree ◽  
Physical Chemical ◽  
Polycyclic Aromatic

Introduction: A graph is supposed to be regular if all vertices have equal degree, otherwise irregular. Materials and Methods: Polycyclic aromatic hydrocarbons are important combusting material and considered as class of carcinogens. These polycyclic aromatic hydrocarbons play an important role in graphitisation of medical science. A topological index is a function that assigns a numerical value to a (molecular) graph which predicts various physical, chemical, biological, thermodynamical and structural properties of (molecular) graphs. An irregular index is a topological index that measures the irregularity of atoms with respect to their bonding for the chemical compounds which are involved in the under studying graphs. Results and Discussion: In this paper, we will compute an analysis of distance based irregular indices of polycyclic aromatic hydrocarbons. A comparison among the obtained indices with the help of their numerical values and the 3D presentations is also included. The efficient and steady indices of polycyclic aromatic hydrocarbons are addressed in the form of their irregularities. Conclusion: Connection based study of the molecular graphs is more suitable than the degree based irregularity indices.

Magnetic magnesium oxide composites for rapid removal of polycyclic aromatic hydrocarbons and cadmium ions from water

2020 ◽  
Vol 17 (7) ◽  
pp. 479
Author(s):  
Dongqin Tan ◽  
Jing Jin ◽  
Cuicui Guo ◽  
Dhanjai ◽  
Jiping Chen
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Three Dimensional ◽  
Precipitation Method ◽  
Precipitation Process ◽  
Cadmium Ions ◽  
Potential Applications ◽  
Equilibrium Data ◽  
Polycyclic Aromatic ◽  
Almost All

Environmental contextRemediation of wastewater containing polycyclic aromatic hydrocarbons and metals is essential to limit adverse effects on the environment and human health. Using a simple precipitation method, we prepared porous magnetic MgO hybrids for use as a material for removing pollutants from wastewater. The material showed excellent removal performance for 12 polycyclic aromatic hydrocarbons and cadmium ions, and thus has potential applications in wastewater treatment. AbstractHierarchical porous magnetic MgO hybrids (Fe3O4/MgO) are controllably synthesised based on a facile precipitation process. The resulting material displays a three-dimensional architecture with nest-like morphology, large surface area (135.2m2 g−1) and uniform mesochannels (5–35nm). The adsorption equilibrium data of target polycyclic aromatic hydrocarbons (PAHs) on Fe3O4/MgO sorbents are described by the Langmuir isotherm model. The composites show a strong tendency for the removal of PAHs owing to their porous structure that possesses an excellent affinity for PAHs. Under the optimal conditions, a removal of more than 70% is achieved for 12 PAHs. The materials also exhibit a good removal ability of cadmium (Cd2+) from water with fast adsorption (<5min) and high removal percentage (>80%). Moreover, the composites possess sufficient magnetism for separation. To demonstrate the performance of the sorbents, Fe3O4/MgO is exposed to aqueous samples spiked with low concentrations of PAHs and Cd2+. In almost all cases, the composites are superior to the commercially available sorbents as well as un-functionalised Fe3O4 nanoparticles. Therefore, this work provides a promising approach for the simultaneous removal of PAHs and Cd2+ from water using multifunctional MgO microspheres.

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