The Re(I) complexes [Re(HPAN)(CO)(3)Cl], 1, and [Re(2)(PAN)(2)(CO)(6)]·C(6)H(12), 2·C(6)H(12), have been prepared by reacting [Re(CO)(5)Cl] with HPAN. Here (PAN)(-) is the deprotonated form of 1-(2-pyridylazo)-2-naphthol. A subsequent reaction of [Re(HPAN)(CO)(3)(CF(3)SO(3))] with a chelating diphosphine ligand generates [Re(PAN)(CO)(P-P)]·CH(2)Cl(2), 3·CH(2)Cl(2). The structures of the complex...

This work deals with a portable device system applied to detect and classify different metallic ions as proposed and developed, aiming its application for hydrological monitoring systems such as rivers, lakes and groundwater. Considering the system features, a portable colorimetric system was developed by using a multispectral optoelectronic sensor. All the technology of quantification and clas...

A new visual colorimetry for trace antimony(V) based on ion-pair solid-phase extraction to a PTFE-type membrane filter with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) ion ([Co(5-Cl-PADAP)(2)](+)) has been developed. Experiments showed that hexachloroantimonate(V) ion (SbCl(6)(-)) was adsorbed with [Co(5-Cl-PADAP)(2)](+) to the front surface of the PTFE filter. The adsorpt...

A field flow preconcentration system for copper determination in seawater is described. Seawater samples are collected and preconcentrated in situ by passing them using a peristaltic pump through a minicolumn packed with Amberlite XAD-4 impregnated with the complexing agent 1-(2-pyridylazo)-2-naphthol. Thus, copper is preconcentrated without the interference of the saline matrix. Once in the la...

mntABC from Neisseria gonorrhoeae encodes an ABC permease which includes a periplasmic divalent cation binding receptor protein of the cluster IX family, encoded by mntC. Analysis of an mntC mutant showed that growth of N. gonorrhoeae could be stimulated by addition of either manganese(II) or zinc(II) ions, suggesting that the MntABC system could transport both ions. In contrast, growth of the ...

This paper presents an experimental study on the dissolution kinetics and solvent extraction of total gold from Ijero-ekiti (Nigeria) gold ore deposit by hydrochloric acid leaching followed by extraction with Tributylphosphate (TBP) in kerosene. The leaching investigation showed that the gold ore dissolution in HCl solution increases with increasing acid concentration, temperature and with decr...

Manganese is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range 7.5-10.5 from large volumes of aqueous solutions of various samples. After filtration, each solid mass consisting of the manganese complex and naphthalene was dissolved with 5 ml of dimethylformamide...

Manganese is an essential micronutrient for all organisms; however at high concentrations it has a toxic effect. Manganese toxicity is a serious constraint to crop cultivation since it is taken-up by plants and can easily be passed into the food chain again causing symptoms of Parkinson’s disease. A fully validated square-wave adsorptive cathodic stripping voltammetry method has been developed ...

A spectrophotometric and first derivative spectrophotometric method was developed in aquatic Tween 80 micellar solutions for selective determination of nickel without using any pre-separation step. 1-(2-Pyridylazo)2-naphthol (PAN), as a sensitive chromogenic complexing agent formed a red-colored Ni(II)-PAN complex in Tween 80 media with satisfactory solubility and stability. Conditions such as ...