scholarly journals On Face Index of Silicon Carbides

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Xiujun Zhang ◽  
Ali Raza ◽  
Asfand Fahad ◽  
Muhammad Kamran Jamil ◽  
Muhammad Anwar Chaudhry ◽  
...  
Keyword(s):  
Physical Properties ◽  
Computer Networks ◽  
Chemical Structure ◽  
Topological Indices ◽  
Graph Invariant ◽  
Graph Invariants ◽  
Chemical Structures ◽  
Boiling Points ◽  
Silicon Carbides ◽  
The Face

Several graph invariants have been defined and studied, which present applications in nanochemistry, computer networks, and other areas of science. One vastly studied class of the graph invariants is the class of the topological indices, which helps in the studies of chemical, biological, and physical properties of a chemical structure. One recently introduced graph invariant is the face index, which can assist in predicting the energy and the boiling points of the certain chemical structures. In this paper, we drive the analytical closed formulas of face index of silicon carbides Si2C3−Ia,b, Si2C3−IIa,b, Si2C3−IIIa,b, and SiC3−IIIa,b.

scholarly journals Topological study of the para-line graphs of certain pentacene via topological indices

2018 ◽  
Vol 16 (1) ◽  
pp. 1200-1206 ◽  
Author(s):  
Zeeshan Saleem Mufti ◽  
Muhammad Faisal Nadeem ◽  
Wei Gao ◽  
Zaheer Ahmad
Keyword(s):  
Molecular Structure ◽  
Real Number ◽  
Chemical Structure ◽  
Topological Index ◽  
Line Graph ◽  
Chemical Properties ◽  
Topological Indices ◽  
Molecular Structures ◽  
Line Graphs ◽  
Graph Invariant

AbstractA topological index is a map from molecular structure to a real number. It is a graph invariant and also used to describe the physio-chemical properties of the molecular structures of certain compounds. In this paper, we have investigated a chemical structure of pentacene. Our paper reflects the work on the following indices:Rα, Mα, χα, ABC, GA, ABC4, GA5, PM1, PM2, M1(G, p)and M1(G, p) of the para-line graph of linear [n]-pentacene and multiple pentacene.

scholarly journals Topological Indices of Carbon Graphite and Crystal Cubic Carbon Structures via M Polynomials

2018 ◽  
Author(s):  
Wei Gao ◽  
Waqas Nazeer ◽  
Amna Yousaf ◽  
Shin Min Kang
Keyword(s):  
Graph Theory ◽  
Chemical Structure ◽  
Molecular Graph ◽  
Topological Indices ◽  
Molecular Structures ◽  
Chemical Graph ◽  
Boiling Points ◽  
Chemical Graph Theory ◽  
Carbon Structures ◽  
Carbon Crystal

Graph theory plays a crucial role in modeling and designing of chemical structure or chemical network. Chemical Graph theory helps to understand the molecular structure of molecular graph. The molecular graph consists of atoms as vertices and bonds as edges. Topological indices capture symmetry of molecular structures and give it a mathematical language to predict properties such as boiling points, viscosity, the radius of gyrations etc. In this article, we study the chemical graph of carbon Crystal structure of graphite and cubic carbon and compute several degree-based topological indices. Firstly we compute M-Polynomials of these structures and then from these M-polynomials we recover nine degree-based topological indices.

Relationships between Chemical Structures of Crosslink Sites and Physical Properties of Vulcanized Rubbers. Part V. Analysis of Chemical Structures of Combined Sulfur in Crosslink Sites for Various EPDM Vulcanizates

1970 ◽  
Vol 43 (2) ◽  
pp. 424-430 ◽  
Author(s):  
M. Imoto ◽  
Y. Minoura ◽  
K. Goto ◽  
H. Harada ◽  
K. Nishihira ◽  
...  
Keyword(s):  
Physical Properties ◽  
Chemical Structure ◽  
Model Compounds ◽  
Chemical Structures ◽  
Curing Agents

Abstract Various EPDM vulcanizates with different chemical structures of crosslink sites, such as C—C, C—R—C and C—Sz—C linkage, were obtained by using a variety of curing agents. C—Sz—C linkage was separated into polysulfide linkage and monosulfide linkage by using the LiAlH4 method which was confirmed beforehand with model compounds. The relationships between the chemical structure of combined sulfur in the crosslink sites and the type of curing agents used were clarified. For example, the mole ratios of polysulfide linkage to all the combined sulfurs in the vulcanizates by using DCP—S8, TMTD, S8—TMTD and S8-zinc dimethyldithiocarbamate curing system were respectively 0.35, 0.25, 0.53 and 0.82 at 160° C for 45 minutes. But in DCP—S8 curing system considerable C—C linkages seemed to be formed in addition to the C—Sz—C linkage.

scholarly journals Valency-Based Descriptors for Silicon Carbides, Bismuth(III) Iodide, and Dendrimers in Drug Applications

2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Qi-Zhao Li ◽  
Abaid ur Rehman Virk ◽  
Kashif Nazar ◽  
Imran Ahmed ◽  
Iskander Tlili
Keyword(s):  
Three Dimensional ◽  
Topological Indices ◽  
Inorganic Compound ◽  
Inorganic Analysis ◽  
Graph Invariant ◽  
Compound A ◽  
Chemical Graph ◽  
The Core ◽  
Chemical Graph Theory ◽  
Silicon Carbides

Silicon carbide (SiC), also called carborundum, is a semiconductor containing silicon and carbon. Dendrimers are repetitively branched molecules that are typically symmetric around the core and often adopt a spherical three-dimensional morphology. Bismuth(III) iodide is an inorganic compound with the formula BiI3. This gray-black solid is the product of the reaction between bismuth and iodine, which once was of interest in qualitative inorganic analysis. In chemical graph theory, we associate a graph to a compound and compute topological indices that help us in guessing properties of the understudy compound. A topological index is the graph invariant number, calculated from a graph representing a molecule. Most of the proposed topological indices are related either to a vertex adjacency relationship (atom-atom connectivity) in the graph or to topological distances in the graph. In this paper, we aim to compute the first and second Gourava indices and hyper-Gourava indices for silicon carbides, bismuth(III) iodide, and dendrimers.

scholarly journals Chemical structure and physical properties of diamond-like amorphous carbon films prepared by magnetron sputtering

1990 ◽  
Vol 5 (11) ◽  
pp. 2543-2554 ◽  
Author(s):  
N-H. Cho ◽  
K. M. Krishnan ◽  
D. K. Veirs ◽  
M. D. Rubin ◽  
C. B. Hopper ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Magnetron Sputtering ◽  
Physical Properties ◽  
Band Gap ◽  
Amorphous Carbon ◽  
Chemical Structure ◽  
Optical Band Gap ◽  
Mass Density ◽  
Carbon Films ◽  
Chemical Structures

Thin films of amorphous carbon (a–C) and amorphous hydrogenated carbon (a–C:H) were prepared using magnetron sputtering of a graphite target. The chemical structures of the films were characterized using electron energy loss spectroscopy (EELS) and Raman spectroscopy. The mass density, hardness, residual stress, optical band gap, and electrical resistivity were determined, and their relation to the film's chemical structure are discussed. It was found that the graphitic component increases with increasing sputtering power density. This is accompanied by a decrease in the electrical resistivity, optical band gap, mass density, and hardness. Increasing the hydrogen content in the sputtering gas mixture results in decreasing hardness (14 GPa to 3 GPa) and mass density, and increasing optical band gap and electrical resistivity. The variation in the physical properties and chemical structures of these films can be explained in terms of the changes in the volume of sp2-bonded clusters in the a–C films and changes in the termination of the graphitic clusters and sp3-bonded networks by hydrogen in the a–C:H films.

scholarly journals Degree-Based Topological Indices of Boron B12

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Nouman Saeed ◽  
Kai Long ◽  
Zeeshan Saleem Mufti ◽  
Hafsa Sajid ◽  
Abdul Rehman
Keyword(s):  
Chemical Structure ◽  
Chemical Reactivity ◽  
Molecular Descriptor ◽  
Topological Indices ◽  
Connectivity Index ◽  
Melting Points ◽  
Zagreb Index ◽  
Boiling Points ◽  
Electronic Parameters ◽  
Atom Bond

Topological index sometimes called molecular descriptor is a numerical value which associates a chemical composition for correlating chemical structure with numerous physical properties, chemical reactivity, or biological activity. In this paper, we study some topological indices of boron and try to correlate the physicochemical properties such as freezing points, boiling points, melting points, infrared spectrum, electronic parameters, viscosity, and density of chemical graphs. We discuss these topological indices, and some of them are mentioned here such as Randic index, the first general Zagreb index, the general sum connectivity index, hyper-Zagreb index (HM), the atom-bond connectivity index (ABC), the geometric-arithmetic index (GA), the harmonic index (H), and the forgotten index (F).

Chemical structure of diamond-like carbon thin films

1990 ◽  
Vol 48 (4) ◽  
pp. 710-711
Author(s):  
N.-H. Cho ◽  
K.M. Krishnan ◽  
D.B. Bogy
Keyword(s):  
Electrical Resistivity ◽  
Chemical Structure ◽  
Diamond Like Carbon ◽  
Chemical Structures ◽  
Sputtering Power ◽  
Data Aquisition ◽  
Equilibrium Phases ◽  
Electron Energy Loss ◽  
Power Densities ◽  
Preparation Techniques

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.

scholarly journals A Further Comprehensive Review on the Phytoconstituents from the Genus Erythrina

2020 ◽  
Vol 23 (1) ◽  
pp. 65-77 ◽  
Author(s):  
Mohammad Musarraf Hussain
Keyword(s):  
Chemical Structure ◽  
Biological Activities ◽  
Chemical Constituents ◽  
Pharmaceutical Journal ◽  
Significant Source ◽  
Comprehensive Review ◽  
Chemical Structures ◽  
Previous Review

Erythrina is a significant source of phytoconstituents. The aim of this review is to solicitude of classification, synthesis, and phytochemicals with biological activities of Erythrina. In our previous review on this genus (Hussain et. al., 2016a) fifteen species (Erythrina addisoniae, E. caribeae, E. indica, E. lattisima, E. melanacantha, E. mildbraedii, E. poeppigiama, E. stricta, E. subumbrans, E. veriagata, E. vespertilio, E. velutina, E. zeberi, E. zeyheri and E. americana) have been studied and 155 molecules with chemical structures were reported. A further comprehensive review was done upon continuation on the same genus and thirteen species (E. abyssinica, E. arborescens, E. berteroana, E. burttii, E. caffra, E. coralloids, E. crista-galli, E. fusca, E. herbaceae, E. lysistemon, E. mulungu, E. speciosa and E. tahitensis) of Erythrina have been studied and 127 compounds are reported as phytoconstituents with their chemical structure in this review. Erythrina crista-galli and E. lysistemon consist of highest number of chemical constituents. Bangladesh Pharmaceutical Journal 23(1): 65-77, 2020

scholarly journals Topological Indices of Para-line Graphs of V-Phenylenic Nanostructures

2019 ◽  
Vol 17 (1) ◽  
pp. 260-266 ◽  
Author(s):  
Imran Nadeem ◽  
Hani Shaker ◽  
Muhammad Hussain ◽  
Asim Naseem
Keyword(s):  
Chemical Properties ◽  
Topological Indices ◽  
Structural Chemistry ◽  
Line Graphs ◽  
Physical And Chemical Properties ◽  
Graph Invariants ◽  
Molecular Graphs ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The degree-based topological indices are numerical graph invariants which are used to correlate the physical and chemical properties of a molecule with its structure. Para-line graphs are used to represent the structures of molecules in another way and these representations are important in structural chemistry. In this article, we study certain well-known degree-based topological indices for the para-line graphs of V-Phenylenic 2D lattice, V-Phenylenic nanotube and nanotorus by using the symmetries of their molecular graphs.

Sign in / Sign up

Export Citation Format

Share Document