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Evaluation and Identification of Genetic Variation Pattern in Cowpea [Vigna unguiculata (L.) Walp] Accessions Using Multivariate Analyses DOI: http://dx.doi.org/10.6000/1927-5129.2015.11.22 Published: 27 February 2015 |
Abstract: Thirty accessions of cowpea from Ebonyi, Enugu and Kogi States, Nigeria were used for the study. Seeds of the accessions were randomized in a plot measuring 50x50 meters for three growing seasons. Our results on yield and yield-related traits showed that three principal components were extracted, which contributed 82.23% of the total variability. It revealed that number of seeds pod-1, 100-seed weight, pod length, days to 50% maturity, seed yield, number of leaves plant-1 contributed significantly to the total genetic variability while for proximate composition, four principal components accounted for 93.75% of the total genetic divergence. Cluster analysis revealed that accessions were grouped not necessarily based on geographical location but genetics. Selection for high yielding accessions should be done on cluster 2 as we recommend selection and hybridization of accessions from cluster 1, 2, and 3 for optimal benefit. Keywords: Germplasm collection, cowpea, selection, hybridization, multivariate analysis. Download Full Article |
Liquid-Phase Homogeneous Catalytic Oxidation of Gas Oil: Elucidation of Complex Chemical Transformation Network DOI: http://dx.doi.org/10.6000/1927-5129.2015.11.19 Published: 26 February 2015 |
Abstract: An attempt has been made to elucidate the extremely complex chemical changes that take place when gas oils (middle distillates such as high speed diesel) are subjected to liquid phase homogeneous oxidative processing in the presence of the redox couple Co(III)/Co(II). For this purpose dilute solutions of gas oil in wet acetic acid have been treated with air under carefully controlled conditions of temperature, pressure and air flow rate. Reaction products are extracted in chloroform from an ice cold aqueous solution of the reaction mixture. Both instrumental (FTIR) and kinetic analyses endorse each other and thereby prove the sequential nature of the reaction resulting in the formation of diverse products through decomposition of the intermediate hydroperoxides, which are unstable in the presence of the catalytic redox couple Co(III)/Co(II).
Keywords: Oxidation, Homogeneous catalysis, gas oils, middle distillates, hydrocarbons, hydroperoxides. |
Carbazole Alkaloids from Stem Bark of Murraya koenigii (L.) Spreng DOI: http://dx.doi.org/10.6000/1927-5129.2015.11.21 Published: 26 February 2015 |
Abstract: Murraya koenigii (L.) Spreng(curry patta) has different therapeutic uses and rich source of carbazole alkaloids. Phytochemical studies on the stem bark of M. koenigii yielded one new carbazole alkaloid, afifine, along with two known carbazole alkaloids, mahinimbine and girinimbine. These compounds were isolated using chromatographic methods and identified using spectroscopic techniques.
Keywords: Carbazole, afifine, Curry patta. |
Thermal Transformation of Indigenous Diaspore DOI: http://dx.doi.org/10.6000/1927-5129.2015.11.20 Published: 26 February 2015 |
Abstract: Indigenous diaspore is a high density hard mineral. It becomes harder on heating up to 550oC. The dispore has been characterized thermally by thermal gravimetric analysis and x-ray diffraction. Results show that the indigenous mineral increases its density after heating at various temperatures for 1 hour. Increase in density points out the increase in hardness due to the formation of a more crystalline compact material corundum using as abrasive.
Keywords: Diaspore, Corundum, TGA, XRD. |
Synthesis, Characterization, In-Vitro Antimicrobial and Antioxidant Activities of Co+2, Ni+2, Cu+2 and Zn+2 Complexes of 3-(2-(2-hydroxy-3-methoxybenzylidene)hydrazono)indolin-2-one DOI: http://dx.doi.org/10.6000/1927-5129.2015.11.17 Published: 23 February 2015 |
Abstract: Four novel complexes of “3-(2-(2-hydroxy-3-methoxybenzylidene)hydrazono)indolin-2-one” have been synthesized with Co+2, Ni+2, Cu+2 and Zn+2. Physical and analytical techniques including CHN, IR, UV-Vis, AAS, molar conductivity values and magnetic susceptibility data were used to characterize all complexes. The bis Schiff base ligand i.e. 3-(2-(2-hydroxy-3-methoxybenzylidene)hydrazono)indolin-2-one, acted as a tridentate ligand and coordinated through phenolic oxygen, azomethine nitrogen and carbonyl group. Low values of molar conductance suggested the non-electrolyte nature of all complexes. Elemental analysis of complexes indicated the 1:1 metal to ligand mole ratios for [Cu(Inh)(OAc)] and [Zn(Inh)(OAc)] metal complexes and 1:2 metal to ligand mole ratios for [Co(Inh)2] and [Ni(Inh)2] metal complexes. Square planner geometry is proposed for [Cu(Inh)(OAc)] and distorted tetrahedral geometry is proposed for [Zn(Inh)(OAc)] while octahedral geometries are proposed for [Co(Inh)2] and [Ni(Inh)2] metal complexes. Antimicrobial and antioxidant studies were performed for all compounds and it was discovered that the complexes are more potent antibacterial and antifungal agents while the ligand exhibited comparatively more DPPH (1,1-diphenyl-2-picryl-hydrazil) radical scavenging activity than the complexes. Keywords: Bis Schiff base, Transition metal complexes, Antimicrobial, Antioxidant. Download Full Article |