Mircea V. Diudea

Wiener and Hyper-Wiener Numbers in a Single Matrix (2008)

Mircea V. Diudea

Abstract: A novel unsymmetric square matrix, WPU, is proposed for calculating both Wiener, W, 1 and hyper-Wiener, WW, 2 numbers. This matrix is constructed by using single endpoint characterization...

Toranes Versus Torenes (2008)

Mircea V. Diudea, Bazil Parv B

Abstract Construction of polyhex and other tiled tori starting from square-like tori is presented. Leapfrog transformation of both linear and angular polyhex isomers is discussed and illustrated....

CYCLIC GRAPHS WITH DEGENERATE SEQUENCES: A STUDY OF SIMILARITY* (2008)

Mircea V. Diudea

Abstract Similarity of two sets of cycle-containing molecular graphs: spiro-alkanes and full Hamiltonian detour cubic cages, is discussed in terms of inter- and intra-molecular similarity. Molecular...

HOSOYA POLYNOMIAL IN TORI (2008)

Mircea V. Diudea

Abstract. The Hosoya polynomial is defined as a distance-based increasing power sequence. Analytical formulas for calculating this polynomial in several classes of toroidal nets are given. The Wiener...

Fantasmagoric Fulleroids Revisited (2008)

Mircea V. Diudea

New strange fulleroids are built up by using the three classical composite map operations: tripling (leapfrog Le), quadrupling (chamfering Q) and septupling (capra Ca) on the starting structure...

Dual Descriptors in the Calculation of the Wiener Numbers (2008)

Mircea V. Diudea, Corina M. Pop, Gabriel Katona, Andrey A. Dobrynin

Wiener, W, and hyper-Wiener, WW, numbers can be calculated mainly on the ground of two basic matrices: Wiener, W, and distance, D, respectively. They, and their derived matrices and numbers, are...

Omega Polynomial (2008)

Mircea V. Diudea

ABSTRACT. A new counting polynomial, called the “Omega ” Ω(G, x) polynomial, is proposed on the ground of quasi-orthogonal cut “qoc ” edge strips in a bipartite lattice. Within a qoc not...

ABSTRACT Topological Substituent Descriptors (2008)

Mircea V. Diudea, Lorentz Jäntschi, Ljupčo Pejov

reducing the cost of biological screening, computational methods are carried out for evaluating the biological activity of organic compounds. Often a class of bioactives differ only in the...

Szeged Matrices and Related Numbers (2008)

Mircea V. Diudea, Ovidiu M. Minailiuc, Gabriel Katona, Ivan Gutman

Abstract: A new unsymmetric matrix, SZu (unsymmetric Szeged matrix) is proposed by analogy to the matrix CJu (unsymmetric Cluj matrix) [1,2]. It is defined and exemplified both for acyclic and...

The Structural Interpretation of the Randi � Index # (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Ernesto Estrada, Biochem Press, E. Estrada, Ernesto Estrada

Motivation. The Randi � index is one of the most successful molecular descriptors in structure–property and structure–activity relationships studies. In spite of some attempts to interpret the...

Building–Block Computation of the Ivanciuc–Balaban Indices for the Virtual Screening (2008)

Mircea V. Diudea, Biochem Press, O. Ivanciuc, Ovidiu Ivanciuc, Ovidiu Ivanciuc, Ovidiu Ivanciuc

Motivation. The discovery of drug leads is significantly accelerated by in silico screening of molecular libraries, that starts from a collection of chemical compounds with a high structural...

Internet Electronic Journal of Molecular Design (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Biochem Press, S. �s. Liu, H. �l. Liu, Y. �y. Shi, ...

Inhibition by 2,3�Diarylcyclopentenones Based on MEDV–13, Internet Electron. J. Mol. Des.

A Modified Distance Matrix to Distinguish Cis/Trans Isomers (2008)

Mircea V. Diudea, Of Cycloalkanes, Chenzhong Cao, Hua Yuan, Biochem Press, C. Cao, ...

The general distance matrix D was modified to distinguish cis/trans isomers of cycloalkanes. A new topological index, VDI(±1), was derived from the modified distance matrix (Dmod) according to the...

Internet Electronic Journal of Molecular Design (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Valentin Gogonea, V. Gogonea, Valentin Gogonea

The paper presents an overview of the development of the QM/MM method and its application to the study of enzyme reactivity. Different approaches for the treatment of QM/MM boundary (link–atom,...

The Block–Polynomials and Block–Spectra of Dendrimers # (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Vladimir R. Rosenfeld, Mircea V. Diudea, V. R. Rosenfeld, M. V. Diudea, ...

Motivation. Dendrimers represent a novel class of hyperbranched supramolecular structures, that promoted novel fundamental and applicative research. Applications of dendrimers include simulation of...

Quantitative Descriptor for SNP Related Gene Sequences # (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Ashesh N, Papiya N, Subhash C. Basak, Biochem Press, ...

Motivation. The rapid growth of DNA sequence information relating to various gene sequences makes it imperative to have quantitative measures to compare and contrast the different sequences. This is...

Internet Electronic Journal of Molecular Design (2008)

Ovidiu Ivanciuc, Mircea V. Diudea

Motivation. This report was motivated by a recent work of Gutman, Rücker and Rücker on walks in simple molecular graphs, i.e., graphs without multiple edges and loops. Method. Three methods for...

Tailored Similarity Spaces for the Prediction of Physicochemical Properties # (2008)

Ovidiu Ivanciuc, Mircea V. Diudea, Brian D. Gute, Subhash C. Basak, Denise Mills, Douglas M. Hawkins, ...

Motivation. In the past, molecular similarity spaces have been developed from arbitrary sets of molecular properties or theoretical descriptors and the results of property estimation based on these...

Computing the Permanent of the Adjacency Matrix for (2008)

Mircea V. Diudea, Francisco Torrens, Biochem Press, F. Torrens

Motivation. Novel carbon allotropes, with finite molecular structure, including spherical fullerenes are nowadays currently produced and investigated. These compounds have beautiful architectures and...

Kekule structure count in corazulenic fullerenes (2007)

Diudea, Mircea V., Vukicevic, Damir

Tiling modification in fullerene modeling can be achieved by some map operations. In this respect, sequences of classical operations, or single generalized operations, were used to obtain...

Chromatographic Retention Times of Polychlorinated Biphenyls: from Structural Information to Property Characterization (2007)

Lorentz Jäntschi, Sorana D. Bolboacă, Mircea V. Diudea

Abstract: The paper presents a unitary approach of the use of a Molecular Descriptors Family in structure-property/activity relationships, particularly in modelling the chromatographic retention...

Generalized Operations on Maps (2006)

Diudea, Mircea V., Stefu, Monica, John, Peter E., Graovac, Ante

A map M is a combinatorial representation of a closed surface. Convex polyhedra, starting from the Platonic solids and going to spherical fullerenes, can be operated to obtain new objects, with a...

Omega Polynomial in Tubular Nanostructures (2006)

Diudea, Mircea V., Cigher, Simona, Vizitiu, Aniela E., Ursu, Oleg, John, Peter E.

A new counting polynomial, called the »Omega« Ω(G, x) polynomial, was recently proposed by Diudea on the ground of quasi-orthogonal cut »qoc« edge strips in a polycyclic graph. Within a qoc, not...

QSAR Modeling of Antifungal Activity of Some Heterocyclic Compounds (2006)

Ursu, Oleg, Costescu, Adina, Diudea, Mircea V., Parv, Bazil

QSAR analysis of a set of benzoxazoles, benzimidazoles, oxazolo[4,5-b]pyridines and benzothiazoles, showing growth inhibitory activity against Candida albicans, was performed using a multiple...

Fantasmagoric Fulleroids Revisited (2006)

Mircea V. DIUDEA

New strange fulleroids are built up by using the three classical composite map operations: tripling (leapfrog Le), quadrupling (chamfering Q) and septupling (capra Ca) on the starting structure...

Chromatographic Retention Times of Polychlorinated Biphenyls: from Structural Information to Property Characterization (2006)

Lorentz Jäntschi, Sorana D. Bolboaca, Mircea V. Diudea

The paper presents a unitary approach of the use of a Molecular DescriptorsFamily in structure-property/activity relationships, particularly in modelling thechromatographic retention times of...

Cluj and Related Polynomials Applied in Correlating Studies † (2006)

Mircea V. Diudea, A. E. Vizitiu

A counting polynomial P(G,x) is a description of a graph property P(G) in terms of a sequence of numbers so that the exponents express the extent of its partitions while the coefficients are related...

Data Mining. 1. Glycine Content Estimation from Activity Coefficients Measurement (2003)

Lorentz JÄNTSCHI, Mircea V. DIUDEA

The paper presents a method to estimate the glycine content from salt aqueous solutions based on standard adding of salt repeated activity coefficients measurement. An original program for data...

Toroidal Fullerenes from Square Tiled Tori (2002)

Mircea V. Diudea, Ioan Silaghi-Dumitrescu, Bazil Parv

Novel carbon allotropes, with finite molecular structure, including spherical (classical) fullerenes, capsulenes, tubulenes, barrellenes, and torrenes are nowadays currently produced and...

The Block-Polynomials and Block-Spectra of Dendrimers (2002)

Vladimir R. Rosenfeld, Mircea V. Diudea

Dendrimers represent a novel class of hyperbranched supramolecular structures that promoted novel fundamental and applicative research. Applications of dendrimers include simulation of enzymatic...

Topological Substituent Descriptors (2002)

Mircea V. DIUDEA, Lorentz JÄNTSCHI, Ljupčo PEJOV

Motivation. Substituted 1,3,5-triazines are known as useful herbicidal substances. In view of reducing the cost of biological screening, computational methods are carried out for evaluating the...

Topology of naphthylenic tori (2002)

Mircea V. Diudea

Novel naphthylenic tori, generated by suitable modifications (that include the leapfrog procedure) of a square net embedded on the torus, are characterised by the ring spiral code, Hosoya polynomial...

Abbreviations and notations Topological Substituent Descriptors (2002)

Mircea V. Diudea, Lorentz Jäntschi, Ljupčo Pejov, Mircea V. Diudea, Lorentz Jäntschi, Ljupčo Pejov

Motivation. Substituted 1,3,5-triazines are known as useful herbicidal substances. In view of reducing the cost of biological screening, computational methods are carried out for evaluating the...

Toroidal Fullerenes from Square Tiled Tori # (2001)

Ovidiu Ivanciuc, Mircea V. Diudea, Toroidal Fullerenes, Square Tiled Tori, Mircea V. Diudea, Bazil Pârv, ...

Special issue dedicated to Professor Alexandru T. Balaban on the occasion of the 70 th birthday

Cluj matrix invariants (1997)

Mircea V. Diudea

The newly proposed matrix, CJu (unsymmetric Cluj matrix) is examplified for cycle-containing structures. Its relation with the matrix SZu (unsymmetric Szeged matrix) is discussed both as definition...