Bahattin Gümgüm

Heavy metal pollution in water, sediment and fish from the Tigris River in Turkey

Some heavy metals (Co, Cu, Mo, Ni, Pb, V and Zn) were determined in water, sediments and some fish species (Cyprinion macrostomus and Garra rufa) from the Tigris River. Mo and V were not detected in water and Co, Cu, Ni, Pb, Zn were found low values. Co, Cu, Ni, Pb, V and Zn were found very high levels in the sediments. All the fish samples contain high concentrations of Cu, Ni and Zn, while Co, Mo, Pb and V were not detected. The high concentrations of heavy metals may be directly related to the contamination of the Tigris River by Ergani Copper Plant and the geochemical structure of this region.

Chemical speciation of heavy metals in the Tigris River sediment

Abstract After determination of total heavy metal concentrations in Tigris river sediments, a Tessier sequential extraction technique and a modified form using a microwave heating procedure were applied. Recoveries of total heavy metals from the sediment samples using the microwave and conventional techniques were reasonably comparable, in spite of a big difference in time required. 44–46% of Co, 24–36% of Cu, 69-81 % of Ni, and 55–73% of Zn were found in the residual fraction (i.e. not bioavailable).

The synthesis, spectroscopic and voltametric studies of new metal complexes containing three different vic-dioximes

The synthesis, spectroscopic, and redox properties of some metal complexes with three novel vic-dioxime ligands, N-(1-(2-aminoethyl)piperazine)-phenylglyoxime (L1H2), N-(1-(2-aminoethyl)piperazine)-glyoxime (L2H2), and N,N′-bis(1-(2-aminoethyl)piperazine)-glyoxime (L3H2)], prepared from different glyoxime and 1-(2-aminoethyl)piperazine are reported. The structure of these vic-dioximes have been determined as the anti-form according to 1H NMR, 13C NMR, and FT-IR data. The metal to ligand ratios of Co(II), Ni(II), and Cu(II) complexes were found to be 1 : 2. The Cu(II) complexes of these ligands are proposed to be square planar and Ni(II) complexes of these ligands are proposed to be square planar or octahedral, while the Co(II) complexes are proposed to be octahedral with water molecules as axial ligands. Ni(II), Co(II), and Cu(II) metal complexes are non-electrolytes as shown by their molar conductivities (ΛM) in DMF (dimethyl formamide) at 10−3 M. The structure of ligands and their complexes is proposed from elemental analysis, FT-IR, UV-VIS, 1H NMR, 13C NMR, magnetic susceptibility measurements, and molar conductivity measurements. The cyclic voltammetric measurements of the mononuclear complexes provide an understanding of the electrochemical behaviour of the reduced or oxidized species in DMSO solution.

Synthesis of Esters Under Microwave Irradiation Using Heteropoly Acids as Catalysts

A practical and simple technique for synthesis of esters was developed by using heteropoly acid as catalyst under microwave irradiation in the absence of organic solvents. Alcohols were easily and selectively converted to their acetates and benzoates with excellent yields (≥98%), and in very short time (∼5 min), as environmentally benign.

Solvent-Free Synthesis of Nitrilotriacetamide and Diketopiperazines from Nitrilotriacetic Acid under Microwave Irradiation and Their Antimicrobial Activity

Abstract Efficient synthesis of dioxopiperazines‐diketopiperzines (DKPs)‐ and amide from nitrilotriacetic acid (NTA) using microwave irradiation and classical heating were described. All compounds were characterized using 1H NMR, 13C NMR and elemental analysis. Antimicrobial effects of these compounds are also investigated. All tested compounds showed moderate antimicrobial activity.

Microwave irradiation technique for synthesis of dialkyl dithiophosphoric acids

Microwave heating technique was applied to the preparation of dialkyl dithiophosphoric acids from the reaction of alcohol with phosphorus pentasulphide. A microwave oven (CEM-MDS 2000) was utilized to determine the preparation conditions for the best yield of dialkyl dithiophosphoric acids under atmospheric pressure at various times and power. Six different (C 4 -C 9 ) chain-length of dialkyl dithiophosphoric acids were studied. All experiments were performed in an open Teflon (poly-tetrafluoroethylene) vessel. The results obtained showed that the reaction of dialkyl dithiophosphoric acids can be achieved more rapidly using microwave heating than using conventional procedures.

Microwave Irradiation Technique for the Synthesis of Dialkyl Dithiophoshoric Acids

Abstract Microwave heating technique was applied to the preparation of dialkyl dithiophosphoric acid, from the reaction of alcohol with phosphorus pentasulphide. A microwave oven (CEM-MDS 2000) was utilised to determine the preparation conditions for the best yield of dialkyl dithiophosphoric acids under atmospheric pressure at various times and power. Six different (C4−C9) chain-length of dialkyl dithiophosphoric acids were studied. All experiments were performed in an open Teflon (poly-tetrafluoroethylene) vessel. The results obtained showed that the reaction of dialkyl dithiophosphoric acids can be achieved more rapidly using microwave heating than using conventional procedures.

Preparation, Spectroscopic Investigation and Characterization of Molybdovanadophosphoric Acid and Its Complexes with N,N′-Diethylaniline

Abstract Free H4[PMo11VO40]. 32 H2O (molybdovanadophosphoric acid) was prepared re-producibly as an orange-red crystaline solid. The N,N′-diethylaniline complexes of the molybdovanadophosphoric acid were prepared and investigated for the first time. Various colored complexes were obtained depending on the solvents used and conditions.

Preparation and Characterization of Polyoxometallates of Molybdenum, Tungsten and Their Salts

Abstract In this work, confirmation of the molecular formula and investigation of the structural stability of the prepared various types of heteropoly acids and their salts by TGA are reported. Specific surface areas of the samples were determined by the BET-single point N2 adsorption method. Scanning electron microscopy (SEM) was used for the of surface topography of the samples in the sense of crystalline and amorphous states and the acidities of these solid samples were determined based on the color changes of suitable indicator solutions by the way of a butylamine titration method. Impurities, weight ratios and bonding states of the characteristic elements of the samples were determined from XRD, EDX and FTIR studies. Referee I: S. H. Wasfi Referee II: V. N. Joshi

Spectroscopic and Thermogravimetric Investigation of Cd(II) Dinonyldithiophosphate: Removal of Cadmium from Aqueous Solutions

Dinonyldithiophosphoric acid (HDDTP) was synthesised from the reaction of phosphorus pentasulphide and nonyl alcohol. Dinonyldithiophosphate complex of cadmium [Cd(DDTP)2] was prepared by mixing solutions of Cd(II) with HDDTP in ethanol at room temperature. The acid and its complex were characterised by elemental analysis and spectroscopy. The thermal behaviour of Cd(DNDTP)2 was investigated by thermogravimetric analysis. Removal of Cd(II) from aqueous media by HDDTP solution was also studied. The optimum conditions for removal of Cd(II) were investigated for effects of solvent, pH, contact time, concentration, and inorganic anions. Cd(II) was quantitatively removed from aqueous solutions at the pH range of , under the conditions that the stoichiometric ratio of HDDTP/Cd(II) ≥2/1. It can be stated that contact of the Cd(II) with HDDTP was sufficient for quantitative removing of cadmium from acidic aqueous solutions.