The benzaldehyde−(1R)−(-)−fenchone azine (1) and derivatives (3), (4), (5), (6) and (7) were prepared by heating the desired benzaldehyde derivatives and fenchone hydrazone in boiling ethanol solution in the presence of acetic acid as catalyst for 3 h. Treatment of the ligands (L) with Na2PdCl4H2O or [PdCl2(NCPh)2] in the ratio of 1 : 1 or 2 : 1 gave the complexes of the type PdL2Cl2 (2), (8), (9), (10), (11) and (12) of which the palladium was bonded to the nitrogen near to fenchone residue. Keywords: Fenchone azine, chiral terpene, palladium complexes..

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This study reported on glutamate sensors based on chitosan as a heterogeneous membrane. The linearity was found to vary from 1.0 × 10-5 M to 1.0 × 10-1 M. The limit of detection was 5.0 × 10-6 M and the pH values were in the range from 4 to 6. The presence of ionic species normally found in foodstuffs did not interfere the electrode. The material for proposed electrodes were cheap and environmental friendly and therefore are suggested as alternative tools for the analysis of glutamate. Keywords: Chitosan, heterogeneous membrane, glutamate..

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The construction of a potentiometric copper(II) ion electrode based on 2’-(5-bromo-2-hydroxybenzylidene) toluenesulfonohydrazide (5BrSALMeBSH) as an ionophore has been developed.The designed electrode having a different composition of poly(vinyl chloride) (PVC), plasticizers and ionophore showed that sensor with membrane composition 5BrSALMeBSH: PVC: DOP in the ratio of 7:40:56 (w/w) gave the best response. It exhibited a wide linear response with a Nernstian slope of 29.34 mV per decade over the concentration range of 1.0 x 10-5 – 1.0 x 10-1 M Cu(II) ions. Under the optimized conditions, the electrode has a detection limit of 3.98 x 10-6 M and the working pH range of 3.0 - 6.0 with response time less than the 20s. The proposed electrode is stable for about two months and exhibits good selectivity for Cu(II) ions over Zn2+, Co2+ , Ni2+, Pb2+ ,Mg2+,Ba2+,Ca2+,Cd 2+,Ce3+,K+,Na+.Designation of this easy and inexpensive electrode was used to determine a copper ion in wastewater samples,.....

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The chemically modified multiwalled carbon nanotubes (MWCNTs) paste electrode with chloroplatinum (II) complex for the determination of mercury is presented. The chloroplatinum(II) complex was characterized by nuclear magnetic resonance spectroscopy (NMR), Fourier transforms infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). The capability of the electron transfer rate on the surface of modified electrode evaluated is by electrochemical impedance spectroscopy (EIS). The square wave stripping voltammetry (SWSV) technique was employed to investigate the performance of chloroplatinum(II) complexMWCNTs paste electrode for determination of mercury. Several operational parameters such as the composition ratios of the electrode, type of supporting electrolyte, pH of the solution, and the SWSV parameters were thoroughly investig.....

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Waste dyes such as Congo red at certain levels can damage the environment because of toxicity and may cause malfunctioning of the liver, kidneys, and nerves. Therefore, this study aims to analyze optimum pH, concentration, particle size of the adsorbent, and the eluent flow rate on the adsorption of Congo red by Napa soil (NS). The results showed optimum pH of 6, an initial concentration of 20 mg/L, and a particle size of 75 μm and the optimum flow rate of the eluent of 40 drops/minute. Furthermore, the determination of adsorption at the optimum condition of the NS as adsorbent without treatment (fresh) has a higher capacity than the purified Napa soil. The absorption capacity was 0.37 mg/g and 0.25 mg/g, and desorption at the optimum condition (recovery column) showed that the highest percentage is by using ethanol. Besides reducing the concentration of the Congo red dye and determining the absorption capacity of the adsorbent, the other aim of the adsorbent application is for pre-co.....

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The fabrication of a zinc hydroxide nitrate-sodium dodecylsulfate bispyribac modified with multi-walled carbon nanotube (ZHN-SDS-BP/MWCNT) paste electrode for uric acid and bisphenol A detection was presented in this study. Electrochemical impedance spectroscopy, chronocoulometry, square-wave voltammetry, and cyclic voltammetry were all used to examine the electrocatalytic activities of modified paste electrodes. The modified electrode's sensitivity and selectivity have been considered in terms of the composition of the modifier in percentages, the types of supporting electrolytes used, the pH of the electrolyte, and square-wave voltammetry parameters like frequency, pulse size, and step increment. Square-wave voltammetry is performed by applying a small amplitude square-wave voltage to a scanning potential from -0.3 V to +1.0 V, demonstrating a quick response time and high sensitivity. The ZHN-SDS-BP/MWCNT sensor demonstrated a linear range for uric acid and bisphenol A from 5.0 M to .....

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The development of conductive polyaniline (PANI) membrane doped with copper(II) oxide (CuO) by means of the photopolymerization method has been successfully carried out. The photocurable PANI polymeric material was synthesized by mixing 0.011 g of aniline monomer with 0.016 g of ethylene glycol dimethacrylate (EGDMA) crosslinker, 0.021 g of dimethoxy phenylacetophenone (DMPP) photoinitiator and 0.026 g of CuO dopant. The electrical conductivity analysis showed that the as-synthesized CuO-doped PANI (PANI/CuO) film possessed an optimum electrical conductivity value of 39.8110-3 S cm-1 at the dopant loading of 0.011 g CuO. Chemical elucidation by using Fourier-transform infrared spectroscopy (FTIR) revealed that the PANI/CuO conducting material with several main functional groups e.g., N-H, C-H, C-N, C=C, C=N, C-O and C=O chemical bonds were identified. Meanwhile, optical characterization of the resulting PANI/CuO membrane by using UVvis diffuse reflectance spectrophotometer (DR/UV-vis) .....

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