The cheif aim of the present investigation is to develop Leslie Gower type three species food chain model with prey refuge. The intra-specific competition among the predators is considered in the proposed model. Besides the logistic growth rate for the prey species, Sokol Howell functional response for predation is chosen for our model formulation. The behaviour of the model system thoroughly analyses near the biologically significant equilibria. The linear stability analysis of the equilibria is carried out in order to examine the response of the system. The present model system experiences Hopf bifurcation depending on the choice of suitable model parameters. Extensive numerical simulation reveals the validity of the proposed model.

This study had succeeded in producing a new graphical representation of James abacus called nested chain abacus. Nested chain abacus provides a unique mathematical expression to encode each tile (image) using a partition theory where each form or shape of tile will be associated with exactly one partition.Furthermore, an algorithm of nested chain abacus movement will be constructed, which can be applied in tiling theory.

M(II) Ions using amino acid L- proline as a primary ligand and either Nicotinamide or 8- hydroxyqinoline as secondary ligand, respectively: a. The mixed ligand complexes of composition,[M(pro)2(na)2]. b. The mixed ligand complexes of composition , Na[M(pro)2(Q)]. Where proline (C5H9NO2) symbolized as pro H , Nicotinamide (C6H6N2O) symbolized as (NA) , 8- hydroxyqinoline, (C9H7NO2) symbolized as (8-HQ). The ligands and the metal chlorides were brought into reaction at room temperature (37ºc) in ethanol as solvent .The reaction required the following molar ratios [(1:2:2) metal:2NA:2pro-] and [(1:1:2) metal:Q:2pro-] with M+2 ions, where M = [Mn (II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and pd(II)]. Products were found to be solid crystall

In this publication, several six coordinate bridged-polymeric metal complexes are reported. The reaction of 4,4`-dipyridine with ethyl chloroacetate in mole ratio of 1:2 gave the multidentate carboxylate ligand bis(N-carboxylatomethyl)-4,4`-dipyridinium). The reaction of the ligand with metal chloride and sodium azide resulted in the formation of the required polymeric complexes. Upon complex formation, the carboxylato ligand behaves as a neutral multidantate species. The mode of bonding and overall geometry of the complexes were determined through physicochemical and spectroscopic methods. These studies revealed octahedral geometry about metal centres and complexes of the general formula [Cr2(L)(N3)4]Cl2.H2O, Na2[Ag2(L)(N3)4].H2O and [M2(L

4-Amino-N-(5-methyl-isaxazol-3-yl)-benzenesulfonamide was synthesized by reacting the diazonium salt of sulfamethoxazole with 3-amino phenol. Complexes of Ni(II), Pd(II), Au(III), and Pt(IV) were produced and characterized by atomic absorption, elemental microanalysis, infrared spectroscopy, liquid chromatography–mass spectroscopy, thermogravimetric analysis, different scanning calorimetry, and ultraviolet–visible spectroscopy. Furthermore, the conductivity and magnetic properties were quantified. According to the analytical studies, all complexes were found to possess a 1:2 metal–ligand ratio and were non-electrolytes, except the Au(III) complex electrolyte, which had a 1:1 metal:ligand ratio. The biological activities of some of the

Infrastructure projects take a long time, are complex, multidisciplinary, use different materials and products, and have high risk. These characteristics affect the process of supplying materials. The current paper studies the ability to improve the supply chain process and decrease its cost by identifying the factors that affect it. These factors are used as variables in the mathematical model, which is working under uncertain conditions when the consumption rate of materials is not constant. The information used in this model is obtained from Building Information Modeling (BIM) and Geographical Information System (GIS) techniques and the genetic algorithm is utilized to determine the optimal supplier and the quantities of supplies