Journal of Applied Chemical Research
Volume:8 Issue: 4, Autumn 2014

First, Schiff base iminopyridine ligand has been prepared by the condensation between primary amine, dimethylaniline and active carbonyl group of pyridine carboxaldehyde, then related complexes were synthesized in methanol solution. The ligand and metal complexes have been characterized by elemental analysis, UV, IR, 1H NMR and 13CNMR spectroscopy. The spectroscopic data of metal complexes indicated that the metal ions are complex with azomethine group and pyridine nitrogen atoms. The ligand acts as bidentate with two N sites and can coordinate with metal ion.

Dispersive liquid–liquid microextraction (DLLME) combined with inductively coupled plasma-atomic emission spectrometry (ICP-AES) was applied for the determination of lead in different environmental water samples. Ammonium pyrrolidine dithiocarbamate (APDC), chloroform and ethanol were used as chelating agent, extraction solvent and disperser solvent, respectively. The effective parameters, such as volume of extraction and disperser solvents, sample volume, pH, salt effect, extraction time, centrifuge speed and amount of chelating agent were optimized with the aid of response surface methodology (RMS) and experimental design. Plackett-Burman design (PBD) was used to choose the significance variables for the optimization. The significant factors were optimized using a central composite design (CCD) then a quadratic model between the dependent and the independent variables was built. The proposed method showed good coincidence between the experimental data and predictive value, and it has been successfully employed to determine lead in environmental water samples. The limit of detection was 8 ngmL−1 and, repeatability of the method, described as relative standard deviation, was 5.7% (n = 5).

Oxaliplatinium is an anticancer drug, used in chemotherapy. To investigate the oxaliplatinium structure based on frontier orbital analysis, thermodynamic analysis and natural bond orbital (NBO) theory is the main objective of the present research. The calculated HOMO and LUMO energies show that charge transfer occurs within molecule. The NBO charges, the values of electric dipole moment (μ) of the molecule were computed using DFT calculations. As a result, the optimized geometry shows a good agreement with the similar experimental results.

In this study, ZnO nanopowders and ZnO doped with metals (Cu , Ag- doped ZnO) and (Cd, Ag- doped ZnO) were synthesized by the sol-gel method in order to investigation on the codoping effect on the band gap and photocatalytic activity of ZnO. The synthesized samples are characterized by IR spectroscopy technique. Moreover, the absorption coefficients of the ZnO, Ag-Cd-ZnO and Ag-Cu-ZnO were analyzed by Tauc’s approach and the direct band gap is calculated. According to these results, compared with pure ZnO, the band gap of the Ag-Cd-ZnO and Ag-Cu-ZnO decreases and it is dependent on the content of dopands. Furthermore, photocatalytic activity for all samples was investigated under UV irradiation in an aqueous medium. The results have been revealed that Ag-Cd-ZnO and Ag-Cu-ZnO shown more photocatalytic actitivity in comparison with pure ZnO.

A series of heterobinuclear, thiocyanato-bridged complexes of cations [M(NH2X)6]2, and [M(en)3]2 (where X = H, Ph; M=Cu, Co, Cd, Zn) with anion [Ni(NCS)4]2–have been prepared by 1:1 molar ratio. The complexes have been characterized by FT-IR, 13C NMR and UV vis spectroscopy, metal analysis, magnetic and conductance studies. The complexes have the following composition: [M(NH2X)5][Ni(NCS)4], and [{M(en)2}{Ni(NCS)4}]n. The antibacterial activity of the prepared complexes against the gram positive, Bacillus cereus and gram negative Salmonella typhi, pseudomonas alruginosa, Escherichia coli pathogens also been investigated.

An efficient, recyclable and environmental-friendly synthetic route to polyhdroquinoline
derivatives have been developed via multi-component one-pot Hantzsch reaction of various aromatic aldehyde, 2 equivalents of 5,5-dimethyl-1,3-cyclohexanedione (dimedone), ethyl acetoacetate and ammonium acetate using nano magnesium oxide as a catalyst in ethanol under reflux condition. Reaction with 4-chlorobenzaldehyde was selected as the model reaction and different conditions for temperature, amount of catalyst and kind of solvent have been studied on it. It was found that 0.03 g catalyst in reflux condition and ethanol as solvent is the optimum condition which resulted in 94% yield. The present approach offers several advantages such as short reaction times, easy isolation and purification of product, and safe, non-toxic, recyclable and economic use of catalyst.

In this work, stable crystalline phosphorus yields are obtained in good yields from the 1:1:1 addition reactions between hydrazine derivatives and dialkyl acetylenedicarboxylates in the presence of triphenylphosphine at room temperature in dichloromethane. This synthetic method has merits of high yields, mild reaction conditions, and simple experimental and work-up conditions. The obtained yields exist in solution as a mixture of two geometric isomers. This is because of the restricted rotation around the carbon-carbon partial double bond resulting from conjugation of the yields moiety with the adjacent carbonyl group.

The adsorption of malonic acid on the rice bran was studied under various conditions such as temperature, contact time, adsorbent dose and concentration of adsorbate. Batch adsorption experiments were conducted and the result showed that the adsorption was dependent on all these parameters. The adsorption process obeys the Langmuir and Freundlich adsorption isotherms. The adsorption capacity was found to be 1.24 mg/g. The Sorption of malonic acid on the rice bran was rapid during the first 20 minutes and the equilibrium was found to be attained within 50 minutes. Negative values of Gibbõ s free energy change (ΔG°), show that the adsorption was feasible and spontaneous and negative values of enthalpy change (ΔH°), confirm exothermic adsorption. Adsorption of malonic acid on the rice bran was characterized by Fourier transform infrared (FT-IR) spectroscopy.

The photocatalytic degradation of Acid Red 91 (AR91) and Acid Yellow 23 (AY23) with different molecular structures and different substitute groups using Pt modified TiO2 (Pt- TiO2) nanoparticles was investigated in the presence of visible light irradiation. Pt-TiO2 nanoparticles were prepared with photodiposition method (PD) and characterized by X ray diffraction (XRD), scanning electron micrographs (SEM), energy dispersive X-ray micro analysis (EDX), transmission electron microscope (TEM), and UV-vis diffuse reflection spectra (DRS) techniques. The DRS results indicated that the deposition of platinum on TiO2 promoted the optical absorption in the visible region and made it possible to be excited by visible light. Pt-modification of the surface of TiO2 increased photocatalytic activity under visible light irradiation, depending on dye structure (functional group and reactivity of dyes). By comparing the removal efficiency of AR91 and AY23 at the similar conditions, it was observed that the photodegradation rate of AR91 was faster than that of AY23. In conclusion, photocatalytic mineralization of the dyes was monitored by total organic carbon (TOC) decrease. Above 82 and 94% mineralization of AY23 and AR91 was observed using 2 h irradiation.

The stable phosphonate derivatives have easily synthesized by the reactions involving trialkyl(aryl) phosphites and dimethyl acetylenedicarboxylate in the presence of 4 nitrophenol and/or acid chlorides, dialkyl(aryl) phosphites and N-methylimidazole at 70 oC under solventfree conditions.

Skin infection caused by Tricophyton rubrum and some opportunistic fungi such as Candida. Albicance and Aspergillus. fumigatus occur in various parts of the body and sometimes are difficult to be treated. Antifungal effects of spherical silver nanoparticles (nano-Ag) were investigated in this study. Although silver nanoparticle has long been used as effective inorganic antifungal agent; the antifungal activity of nano-Ag in different size has not been investigated yet. In this study nano-Ag in diameter size of 10, 20, 40 nm were examined. The minimal inhibitory concentration (completive visual growth inhibition) of these nanoparticles ranged from 4-16 μg/ml for all fungal test strain. Thus, the current study indicates nano- Ag may have considerable antifungal activity, deserving further investigation for clinical applications.

The removal of color from synthetic wastewater containing Congo red was experimentally investigated using electrocoagulation process. The effects of operational parameters such as current density, electrolysis time, electrolyte concentration, electrode distance, initial dye concentration, initial pH and temperature on color removal efficiency were investigated in this study. The tentative results showed that Congo red in the aqueous phase was removed effectively by electrocagulation procedure. Optimum operating range for each of these operating variables was experimentally determined. Under the conditions of an initial dye concentration of 50mg/l, electrolysis time 5min, initial pH 7.5, current density 150A/ m2, sodium chloride concentration 10g/l, interelectrode distance 0.5 cm, the color removal efficiency reached 98% when electrical energy consumption in this conditions for the decolorization of the dye solution containing Congo red was 0.46 KWh/m3. Outcomes showed that the first-order rate equation could be described correlation for the decolorization rate of Congo red. The thermodynamic parameters, such as ΔHo, ΔSo and ΔGo, were also determined and evaluated. Further the experimental data were tested with different adsorption isotherm model to describe the electrocoagulation process.