Journal of Advanced Applied Scientific Research (JOAASR)
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Adsorption of copper (II) ions by using low cost activated carbon from aqueous solution
Get PDFIn the present study, adsorption of copper (II) ions from aqueous solution by activated Kigelia africana rind nano carbon (KANC) was investigated under batch mode. The influence of solution pH, sorbent dose, copper (II) ions concentration, contact time, and temperature was studied. The copper (II) ions adsorption was favored with maximum adsorption at pH 6.5. Sorption equilibrium time was observed in 60 min. The equilibrium adsorption data were correlated with Langmuir and Freundlich isotherm models. The kinetics of the adsorption process was tested by pseudo-second order, Elovich and intraparticle diffusion models. It was shown that adsorption of copper (II) ions could be described by the pseudo-second order kinetic model. Thermodynamic parameters such as Gibbs free energy (ΔG0), the enthalpy (ΔH0) and the entropy change of sorption (ΔS0) have also been evaluated and it has been found that the adsorption process was spontaneous, feasible, and exothermic in nature. The results indicated that activated KANC can be used as an effective and low-cost adsorbent to remove Cu (II) ions from aqueous solution
Unexpected efficient reactions of nitrogen nucleophiles with α,β-unsaturated nitriles / esters
Get PDFα,β-Unsaturated compounds containing aldehyde, ketone, nitrile and ester functional groups are versatile precursor for the synthesis of novel organic molecules. All these compounds undergo Michael addition of carbon and other nucleophiles at b-carbon atom of the a,b-unsaturated system. Different carbo- and hetero-cyclic compounds can be synthesized by varying the conditions of cyclisation of the Michael adducts. In this context, it is planned to synthesize pyrazole derivatives and diazepine derivatives by reacting a,b-unsaturated compounds with different Nitrogen nucleophiles such as, o-phenylenediamine etc. The present investigation reports the unexpected hydrogenation of C=C in a,b-unsaturated nitriles and the unexpected synthesis of azine derivatives from a,b-unsaturated nitrileand hydrazinium sulphate
Electrosynthesis of phenolphthalein using cyclic voltammetry technique
Get PDFThe synthesis of the indicator of phenolphthalein has been investigated in this research by an electrochemical method. In this method, electro-synthesis of phenolphthalein was performed in a 2 M solution of phenol and 1 M solution of phthalic anhydride in sulfuric acid medium, using the cyclic voltammetry technique in a potential range of -0.1 to 1.5 V and scan rate 50 mV/s. Ag/AgCl, platinum and graphite electrodes were respectively used as reference, counter and working electrode. The combination of electro-synthesis in accordance with the detailed steps of the purification and the method of determination of the melting point and FT-IR, HPLC, SEM and UV-Vis devices were used and were confirmed to perform diagnostic tests
Elaborated studies on Schiff base homo-binuclear Cu(II) and Co(II) complexes, spectral, thermal, P-XRD and biocidal studies
Get PDFA homo-binuclear Cu(II) and Co(II) complexes were synthesized using a Schiff base ligand derived by condensation of 2,6-diaminopyridine and glyoxal. The reasonable geometry of the Schiff base and its binucleating metal complexes were examined by means of elemental and thermal analyses, molar conductance, 1HNMR, UV–Vis, IR, ESR, P-XRD and mass spectra. The ligand behaved as a polydentate, coordinating through the nitrogen atom of the azomethine group, a nearest nitrogen atom of the pyridine group and the oxygen atom of a glyoxal group. From the spectral studies, a six coordinate environment around the metal dimers was confirmed. The binuclear nature of the metal complexes was assessed from their magnetic susceptibility values. Both of the Schiff base and its metal complexes were also tested for their in vitro antimicrobial activities against some bacterial and fungal strains. Schiff base and the metal complexes were also investigated for its cytotoxic effect against human breast cancer (MCF7) cell lines. 
Synthesis, spectral characterization and DNA/Protein binding studies on Cobalt (II) complex containing Mixed ligand Ethylenediamine with 2-Hydroxy-1-Naphthaldehyde
Get PDFNew cobalt (II) complex has been synthesized and characterized by elemental analysis, UV-Vis, FT-IR and thermal analysis. Binding of this Co (II) complex with calf thymus DNA was investigated by UV-Visible absorption, fluorescence spectroscopy techniques. The intrinsic binding constants Kb of complex with CT-DNA obtained from UV-Vis absorption studies were 4.43 × 105M-1. Further, the in vitro cytotoxic effect of the complexes examined on cancerous cell line, such as human breast cancer cells (MCF-7). 
Preparation and characterization of Cu-Zro2 nanocomposite by DC method
Get PDFCu-ZrO2 nanocomposite coatings prepared by electrodeposition method. In bath solution containing different amount of ZrO2 were studied. The structure, surface morphology, mechanical and corrosion resistance properties of nanocomposite are characterized by varies techniques. Cu-ZrO2 composite coatings have higher micro hardness, compared to pure copper coating. Surface morphology of both Cu and Cu–ZrO2 composite coatings were examined through Scanning electron microscopy. The results show that more number of zirconia particles incorporated into copper matrix and then smooth surface, finer grain sized. The incorporation of ZrO2 particles reduces the particle size. It shows the closer particle-particle contact leads to pore free deposition. The X-ray diffraction was conformed the crystallite size and structure of the electrodeposited Cu and Cu–ZrO2 composite coatings. The average crystallite size calculated from Scherrer equation was ~105 nm for copper and ~67 nm for Cu-ZrO2 composites. The structure of electrodeposited Cu and Cu–ZrO2 composite coatings were crystalline orthorhombic which was confirmed from the JCPDS standard. The corrosion resistance behavior of Cu–ZrO2 composite is examined through Tafel polarization and impedance measurement studies in 3.5% NaCl. The result shows that the Cu–ZrO2 composite coatings have more corrosion resistance than pure Cu coating
IR, UV and CV studies of Schiff base metal complexes derived from o-phenylinediamine with chlorobenzaldehyde
Get PDFA new N2 type Schiff base ligand was prepared by the condensation of o-phenylenediamine with p-chlorobenzaldehyde. The ligand and its mixed-ligand complexes have been characterized by microanalytical data, molar conductance, magnetic susceptibility, IR, UV-Vis., spectra. The data show that they have composition of the type [ML(ox)]Cl2 where M = Cu(II) and Zn(II). The UV-Vis. and magnetic susceptibility data of all these complexes have adopted square-planar geometry around the central metal ion. Moreover, these complexes have higher electrolytic nature confirmed by the molar conductance data. Furthermore, their magnetic susceptibility values provide evidence for the monomeric nature. From the cyclic voltammetric data, both complexes reveal that these complexes are quasi-reversible
Studies on novel o-hydroxyacetophenone substituted triazine based ligand and its metal complexes
Get PDFA novel design of triazine based ligand with o-hydroxyacetophenonenucleus (L) has been synthesized. A series of metal(II) complexes of general formula [ML.H2O][where M = Cu(II), Ni(II), Co(II) and Zn(II)] have been obtained.UV-Visible, magnetic susceptibility, Infrared, 1H NMR, Mass and electron spin resonance (ESR) techniques have been used to elucidate the structures of metal complexes. Spectroscopy and other data show octahedral geometry for metal(II) complexes. The fluorescence spectra of all the complexes revealed the photoactive nature of the complexes. The ligand was found to exhibit better second harmonic generation (SHG) efficiency compared to that of urea and KDP. The ligand and its metal complexes were screened for their antibacterial and antifungal activities. This study revealed the increased antimicrobial activity exhibited by the than the ligand
Molecular Evaluation of the Philippine Best Rubber Clones using Genomic-based Simple Sequence Repeats
Get PDFTo date there are only nine best rubber clones in the Philippines with little knowledge about its molecular information. Nineteen genomic-based simple sequence repeats' (G-SSRs) good genome coverage had provided enough data in evaluating the Philippine best rubber clones (five PB, three RRIM and one Philippine or Phil derived clones) along with two Phil check clones. G-SSRs derived 72 alleles in all with means N, Ne, Ho, and PIC of 3.789, 2.284, 0.569 and 0.508 per G-SSR, respectively. Nine G-SSRs however detected 16 private alleles. AMOVA also revealed 6.37%, 19.26% and 74.37% molecular variance between groups, between and within clones, respectively, with corresponding FST of 0.064. While genetic proximity had a range of 0.184 to 0.487 with corresponding neighborhood-joining tree suggested no similar clones, three groups (PB, RRIM and Phil groups) had delta K of two based from Bayesian structure analysis. Group 1 had RRIM600, RRIM712 and RRIM901 while group 2 had PB217, PB235, PB260, PB311, PB330, SMRX1, UPLBPlant1 and USM1. G-SSRs are suitable for extracting molecular information and distinct alleles, which can be used as reference to authenticate the best rubber clones in the Philippines. Bayesian structure analysis on the other hand assured better resampling strategy and found admixtures. Furthermore, rubber is highly structured in individual level that indicates these clones should be utilized to broaden genetic variability of the Philippine rubber
Synthesis and application of new composite terpolymer for the removal of lead from aqueous solution
Get PDFIn this study, a new composite GO-4-HBDTOF was prepared by coating 4-HBDTOF terpolymer on graphene oxide. The terpolymer and composite were characterized by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy analysis. Batch experiments were carried out to evaluate efficiency of the sorbents 4-HBDTOF and GO-4-HBDTOF composite for the removal of Pb(II) ion from aqueous solutions. The effect of contact time, pH and initial concentration of Pb(II) on the adsorption process were investigated. The equilibrium data were fitted to Langmuir and Freundlich isotherm model. The Langmuir isotherm gave a better representation of data than Freundlich isotherm. From Langmuir adsorption isotherm model the calculated value of monolayer adsorption capacity for composite was found to be higher than that of terpolymer. Thus the newly synthesized terpolymer composite can be used as better adsorbent for the removal of Pb(II) from aqueous solution.