Sami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601The eccentric connectivity index of polycyclic aromatic hydrocarbons (PAHs)64665110478010.33945/SAMI/ECC.2020.6.1ENMehdiAlaeiyanDepartment of Mathematics, Iran University of Science and Technology (IUST) Narmak, 16844, Tehran, Iran0000-0003-2185-5967ChidambaramNatarajanDepartment of Mathematics, Srinivasa Ramanujan Centre, SASTRA Deemed University, Kumbakonam-612 001, India0000-0002-1001-3556GSathiamoorthyDepartment of Mathematics, School of Arts, Science and Humanities, SASTRA Deemed University, Thanjavur-613 401, Tamil Nadu, IndiaMohammad RezaFarahaniDepartment of Mathematics, Iran University of Science and Technology (IUST) Narmak, 16844, Tehran, Iran0000-0003-2969-4280Journal Article20200129Mathematical chemistry is the area of research engaged in new application of Mathematics in Chemistry. Major areas of research in mathematical chemistry include chemical graph theory. Chemical graph theory applies graph theory to mathematical modeling of chemical phenomena. If <em>G=(V(G),E(G)) </em>is a connected graph,where <em>V(G)</em> is a non-empty set of vertices and <em>E(G)</em> is a set of edges, then the <em>eccentric connectivity index</em> of <em>G</em> (denoted by <em>ξ</em>(<em>G</em>)) was defined as <em>ζ(G)</em>= where <em>d<sub>v</sub></em> is the degree of a vertex <em>v </em>and <em>ε</em>(v) is its eccentricity. In this study, we investigated the eccentric connectivity index of <em>polycyclic aromatic hydrocarbons (PAHs)</em>.http://www.echemcom.com/article_104780_02bd41a19d3f49f2d2a96b165b0b625e.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Weighted entropy of penta chains graph65266210480610.33945/SAMI/ECC.2020.6.2ENFarkhandaAfzalDepartment of Humanities and Basic Sciences, Military College of Signals, National University of Sciences and Technology, 44000, Islamabad, Pakistan0000-0001-5396-7598MehmonaAbdul RazaqDepartment of Mathematics and Statistics, The University of Lahore, 54000, Lahore, PakistanDeebaAfzalDepartment of Mathematics and Statistics, The University of Lahore, 54000, Lahore, Pakistan0000-0001-5268-7260SairaHameedDepartment of Mathematics, University of the Punjab, 54000, Lahore, PakistanJournal Article20200130Mathematical chemistry is a branch of theoretical chemistry in which we predict the mathematical structure by means of mathematical tools. In past few decades, many studies have been conducted in this area. This theory has cooperated a significant role in the field of chemistry. The main goal of this study is to calculate the weighted entropies of penta chains. We studied the graph entropies with Randić index, Zagreb indices, atom-bond connectivity, augmented Zagreb index, geometric arithmetic index, and sum connectivity index. We obtained the weighted entropies for the graphs formed of concatenated 5-cycles in one rows and in two rows of various lengths.http://www.echemcom.com/article_104806_a40c8792e4b0e2a0ba86b61954e86fd0.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601New results on eccentric connectivity indices of V-Phenylenic nanotube66367110485110.33945/SAMI/ECC.2020.6.3ENZaheerAhmadKhwaja Fareed University of Engineering and Information Technology, Rahim Yar Khan, Pakistan0000-0002-9860-9038MariaNaseemAbdus Salam School of Mathematical Sciences, GC University, Lahore, PakistanMuhammad KamranJamilDepartment of Mathematics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, Lahore, Pakistan0000-0001-5715-9299Muhammad KamranSiddiquiDepartment of Mathematics, Comsats University Islamabad Lahore Campus0000-0002-2607-4847Muhammad FaisalNadeemDepartment of Mathematics, Comsats University Islamabad Lahore Campus0000-0002-3175-7191Journal Article20200130Topological index is a type of molecular descriptor calculated based on the molecular graph of a chemical compound. Topological indices are used for developing the quantitative structure activity relationships (QSARs) in which the biological activity or other properties of the molecules are correlated with their chemical structure. Eccentric connectivity indices are the well-known topological indices in this regards. In this research study, we computed some eccentric connectivity indices of the V-Phenylenic nanotube VPHX[p;q], these are our results.http://www.echemcom.com/article_104851_b4ffd42394fce3595c82a8460fefaf39.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Computation of bond incident degree (BID) indices of complex structures in drugs67267910509710.33945/SAMI/ECC.2020.6.4ENJia-BaoLiuSchool of Mathematics and Physics, Anhui Jianzhu University, Hefei
230601, P.R. China0000-0002-9620-7692Abdul QudairBaigDepartment of Mathematics, COMSATS Institute of Information Technology, Attock, Pakistan0000-0002-8913-5221MuhammadImranDepartment of Mathematical Sciences, United Arab Emirates University, P.O. Box 15551, Al Ain, United Arab Emiratesimrandhab@gmail.comWaqasKhalidDepartment of Mathematics, COMSATS Institute of Information Technology, Attock, Pakistan0000-0001-5527-6563MuhammadSaeedDepartment of Basic Sciences, Riphah International University, Islamabad, PakistanMohammad RezaFarahaniDepartment of Applied Mathematics, Iran University of Science and Technology (IUST), Narmak,Tehran 16844, Iran0000-0003-2969-4280Journal Article20200118The molecular topological descriptors are the numerical in-variants of a molecular graph and are very useful and efficient to predict their bioactivity. Dendrimers are highly branched organic macro-molecules with successive layers or generations of branch units surrounding a central core and have many applications in biology, medicine and drug designs. These are key molecules in nanotechnology and can be put to good use. A great variety of such indices are studied and used in theoretical chemistry and pharmaceutical researchers. Among them, a large number of indices depend only on vertex degrees of the molecular graph. A considerable amount of these vertex-degree-based topological indices can be represented as the sum of edge contributions of graph. These kind of vertex-degree-based topological indices are known as bond incident degree (BID) indices. In this paper, we determine the bond incident degree indices of complex structures in drugs called nanostar dendrimers and compute the closed formula for these indices.http://www.echemcom.com/article_105097_031fabd4e963ed1441ca66da6f9c9ed8.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601On molecular topological descriptors of certain families of nanostar dendrimers68068710509810.33945/SAMI/ECC.2020.6.5ENMuhammadImranDepartment of Mathematical Sciences, United Arab Emirates University P.O Box 17551 Al Ain, United Arab Emirates0000-0002-2827-0462Syed Ahtsham Ul HaqBokharyCentre for Advanced Studies in Pure and Applied Mathematics, Bahauddin Zakariya University, Multan, Pakistansihtsham@gmail.comSadiaManzoorCentre for Advanced Studies in Pure and Applied Mathematics, Bahauddin Zakariya University, Multan, PakistanMuhammad KamranSiddiquiDepartment of Mathematics, Comsats Institute of Information Technology, Sahiwal, Pakistan0000-0002-2607-4847Journal Article20200102In this article, we study the degree based molecular topological indices for some infinite families of Nanostar Dendrimers. We derive the analytical closed formulae for these classes of complex chemical networks. These results are very helpful in understanding and predicting the physico-chemical properties for these chemical structures (Nanostar dendrimers NS2[n], NS3[n], D2[n]).http://www.echemcom.com/article_105098_a2a23a119c64be7eeac377c4843206cd.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Phosphomolybdic acid immobilized chitosan/Fe3O4: an efficient catalyst for the N-alkylation of anilines68870110523410.33945/SAMI/ECC.2020.6.6ENMahdiGhanimatiDepartment of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran0000-0002-3677-7853MasumehAbdoli-SenejaniDepartment of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran0000-0001-8536-9218Mohammad AliBodaghifardDepartment of Chemistry, Faculty of Science, Arak University, 38156-88349, Arak, Iran0000-0001-9732-4746TahereMomeni IsfahaniDepartment of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran0000-0002-6648-9625Journal Article20200305In this work, phosphomolybdic acid immobilized on chitosan/Fe3O4 as a green catalyst was used for the Hofmann N-alkylation of aniline derivatives with alcohols. H3PMo12O40/chitosan/Fe3O4 (PMo/Chit/Fe3O4) was prepared from the phosphomolybdic acid, chitosan, and Fe3O4 MNPs. Several secondary amines were synthesized from primary arylamines with electron‐donating, electron‐withdrawing groups, and alcohols in good to excellent yields. The catalyst could be separated using an external magnet and recovered without reducing its catalytic activity. The optimization of the reaction conditions was evaluated using the response surface method (RSM), involving the Box-Behnken design matrix. The simple procedure, only one byproduct (i.e., water), good to excellent yields, easy separation of the catalyst, short reaction times, and environmentally benign conditions were some advantages of this method.http://www.echemcom.com/article_105234_cb2ccbe1dc0887aad6adfa71135c71b8.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Nano-molar level determination of isoprenaline in pharmaceutical and clinical samples; A nanostructure electroanalytical strategy70271110525910.33945/SAMI/ECC.2020.6.7ENSareh SadatMoshirian-FarahiDepartment of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, IranHassan AliZamaniDepartment of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, Iran0000-0002-3156-2781MohamadrezaAbediDepartment of Applied Chemistry, Quchan Branch, Islamic Azad University, Quchan, IranJournal Article20191109A high sensitive electroanalytical-based sensor for determination of isoprenaline was fabricated by modification of carbon paste electrode (CPE) by NiO-Pt-Pd/CNTs composite as conductive mediator and n-hexyl-3-methylimidazolium hexafluoro phosphate (NHIHP) as conductive binder. The NHIHP/NiO-Pt-Pd/CNTs/CPE was improved the oxidation signal of isoprenaline ⁓3.47 times and reduced oxidation over-potential of drug ⁓180 mV. The pH investigation confirmed that redox behavior of isoprenaline is depended of pH solution with equal value of electron and proton in redox mechanism. The NHIHP/NiO-Pt-Pd/CNTs/CPE was successfully used for determination of isoprenaline in the concertation range 0.003-300 µM with detection limit 0.9 nM by square wave voltammetric method. The standard addition results showed powerful ability of NHIHP/NiO-Pt-Pd/CNTs/CPE as an electroanalytical tool for determination of isoprenaline in the pharmaceutical and clinical samples with recovery data 98.76-105.06%.http://www.echemcom.com/article_105259_d0d00afd36160ca3eb803f6c83942244.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Eccentric connectivity indices of titania nanotubes TiO2[m;n]71272110526110.33945/SAMI/ECC.2020.6.8ENZaheerAhmadKhwaja Fareed University of Engineering and Information Technology, Rahim Yar Khan, Pakistan0000-0002-9860-9038MariaNaseemAbdus Salam School of Mathematical Sciences, GC University, Lahore, PakistanMuhammad KamranJamilDepartment of Mathematics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, Lahore, Pakistan0000-0001-5715-9299ShaohuiWangDepartment of Mathematics, Louisiana College, Pineville, LA 71359, USAMuhammad FaisalNadeemDepartment of Mathematics COMSATS University Islamabad Lahore Campus0000-0002-3175-7191Journal Article20200130The eccentric connectivity index ECI is a chemical structure descriptor that is currently being used for modeling of biological activities of a chemical compound. This index has been proved to provide a high degree of predictability compared to some other well-known indices in case of anticonvulsant, anti-inflammatory, and diuretic activities. The ECI of an infinite class of 1-polyacenic (phenylenic) nanotubes has been recently studied. In this study, we computed Ediz eccentric index and augmented eccentric connectivity index of Titania nanotube TiO2[m;n].http://www.echemcom.com/article_105261_9fbba19d2d3e9ae37cbbd7ddb2fc6b80.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Improving the separation process of fine particles in drilling mud by ultrasonic waves72273010543410.33945/SAMI/ECC.2020.6.9ENAminAmraeiPetroleum, Mining and Material Engineering Department, Islamic Azad University, Central Tehran Branch, Tehran, IranAfshinAkbari DehkharghaniPetroleum, Mining and Material Engineering Department, Islamic Azad University, Central Tehran Branch, Tehran, IranJournal Article20200120Aggregation of solid particles in the drilling fluid has adverse effects on the drilling performance, including blocking drilling pipe, reducing fluid lubrication, and the blowout action. The purpose of this study was to prepare a solution for breaking the adhesion forces between the suspended solids and drilling fluid molecules. To investigate the effect of the ultrasonic waves on the separation of solid particles from reversed emulsion fluid, in vitro studies were conducted. Drilling mud was prepared in the form of different samples and the samples were then irradiated with ultrasonic waves for 2, 5, and 10 min and the intensities of 50, 100, and 150 W/m2. To evaluate the stability of the emulsions and the efficiency of the separation process, caliper (volumetric) and density measurement methods were utilized. The results revealed increased time and intensity of the ultrasonic radiation separates the phases and fine particles from the emulsion, and also increased the stability of reversed emulsion. The increased radiation time and intensity did not have any effect on the drilling mud and only delayed the optimal operation time and energy consumption.http://www.echemcom.com/article_105434_723492ed3c907fec3c551e521c46425c.pdfSami Publishing Company (SPC)Eurasian Chemical Communications2717-05352620200601Study of some topological invariants of subdivided mk graphs73173810544210.33945/SAMI/ECC.2020.6.10ENFarkhandaAfzalDepartment of Humanities and Basic Sciences, Military College of Signals, National University of Sciences and Technology, 44000, Islamabad Pakistan0000-0001-5396-7598MustafaNaeemDepartment of Mathematics and Statistics, The University of Lahore, 54000, Lahore, PakistanFaryalChaudhryDepartment of Mathematics and Statistics, The University of Lahore, 54000, Lahore, PakistanDeebaAfzalDepartment of Mathematics and Statistics, The University of Lahore, 54000, Lahore, Pakistan0000-0001-5268-7260Journal Article20200309An m<sup>k</sup>-graph of a graph G can be defined by taking m≥2 copies G<sub>1</sub>,..., G<sub>m</sub> of a graph G in which every vertex u<sub>t</sub> of copy G<sub>t</sub> is adjacent to a corresponding vertex v<sub>s</sub> of copy G<sub>s</sub>. An m<sup>k</sup>-graph is represented by m<sup>k</sup>(G). In this research study, we discussed some degree based topological indices (connectivity indices) of subdivided m<sup>k</sup>-graph generated by path graph and comb graph. The closed formulas for computing various degree based topological indices of subdivided m<sup>k</sup>-graphs were presented.http://www.echemcom.com/article_105442_1166ce8bc87fd32bb7dbf28c806c6362.pdf