Copper(II) Coordination Compound with 2-Oxonicotinate: Synthesis, Spectroscopic and Electrochemical Studies

Metal organic frameworks (MOFs) are gaining interest for technological purposes due to their intriguing open structure properties such as ion exchange, catalytic properties and application as sensors. To prepare coordination compounds with desired properties, the choice of organic ligand is crucial. This work demonstrates the hydrothermal synthesis of a copper(II) coordination compound with 2-hydroxynicotinic acid. Characterization was based on elemental analyses, ESI-MS, MALDI-TOFMS, FT-IR spectra, thermogravimetric analysis (TGA), and cyclic voltammetry. Electrochemical characterization of the compound prepared was also carried out to find a sensitive and simple method to improve the determination of biologically active thiol substances. From the rectangular voltammetry results, a linear response between 0.2 and 20 μM was obtained with an estimated detection limit of 0.09 μM

Sensitive Electrochemical Determination of Folic Acid Using ex–situ Prepared Bismuth Film Electrodes

The electrochemical behavior of folic acid (FA), at the electrochemically prepared ex situ bismuth film (BiF) on glassy carbon electrode, clearly indicates electrocatalytic nature of the prepared film toward FA reduction (at –0.55 V). Scanning electron microscopy is used for morphological characterization of the prepared BiF. Accordingly, we establishing an electrochemical procedure based on square wave cathodic stripping voltammetry, preceded by accumulation of FA on the BiF electrode (BiFE). This analytical method is optimized and its analytical performance is presented. This electrode displays a two linear response range: 0.1 to 1.0 μmol L–1 and 1.0–10.0 μmol L–1 with sensitivity of 20.10 μA μmol–1 L and 2.28 μA μmol–1 L, respectively. Developed method was validated in compliance with spectrophotometric method. Excellent recovery and standard deviation obtained with BiFE revealed great analytical potential of the proposed method which was applied for the determination of FA in pharmaceuticals formulation. This work is licensed under a Creative Commons Attribution 4.0 International License

Scientific Research Activities of the Department of General and Inorganic Chemistry in the Period 2010–2020

Od utemeljenja Zavoda, akademske godine 1961./62., njegova znanstveno-istraživačka djelatnost bila je usmjerena na elektrokemijska istraživanja metala, pojavu pasiviteta i inhibiciju korozije. Kasnije, ponajprije primjenom elektrokemijskih metoda, proučavaju se fenomeni na granici faza metal│anodni sloj│elektrolitna otopina koji su od značaja za kemijske izvore struje i poluvodičke sustave. Tijekom posljednjih deset godina istraživanja se usmjeravaju u dva smjera: i) ispitivanje utjecaja legirajućih elemenata na dizajn otpornih materijala i biofunkcionalizacija površine biorazgradljivih i biokompatibilnih metalnih implantata; ii) modifikaciju elektroda i njihovih površina u svrhu razvoja novih elektroanalitičkih metoda za određivanje teških metala i biomolekula. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.Since the establishment of the Department of General and Inorganic Chemistry in 1961, at the Faculty of Chemistry and Technology, University of Split, its scientific interest and investigations were focused toward electrochemical research. Consequently, electrochemistry became the backbone of the scientific research and development of the Department. In the last 10 years, scientific interest has been focused on the influence of alloying elements on design of corrosion resistance materials, as well as biofunctionalisation of biodegradable and biocompatible metal-based implants. In addition, development of various electroanalytical methods based on modified electrodes as sensing part of sensors, have been in focus in the recent period. The developed sensors were used for determination of heavy metals or biomolecules. This work is licensed under a Creative Commons Attribution 4.0 International License

Monthly and Seasonal Variations of NO2, SO2 and Black-smoke Located Within the Sport District in Urban Area, City of Split, Croatia

This paper represents, for the first time, scientific data as a part of monitoring air quality in the city of Split. The city has a problem with the air pollution mostly caused by anthropogenic activities and partly by natural origin activities. This study presents results of monthly and seasonal variations of NO2, SO2 and black-smoke as well as the influence of meteorological parameters on observed concentration levels. Average seasonal values for SO2 ranged from 22.54 to 54.81 g m–3, for NO2 from 48.24 to 56.38 g m–3 and for black-smoke from 4.15 to 5.64 g m–3. The results obtained for SO2 and black-smoke were below, while for NO2 were above the limit value of pollutants in the air recommended by Croatian Government (Air Protection Act (OG 178/04); Regulation on limit values of pollutants in air (OG 133/05)). As the result of stable meteorological conditions (high temperatures and drought), the increase in SO2 concentration was significant in summer period, while the concentrations of NO2 and black-smoke were not significantly changed during year and did not depend on other parameters. (doi: 10.5562/cca1966

MULTIVARIATE ANALYSIS OF POLLUTION INDICATORS OF MUNICIPAL WASTEWATER IN SPLIT AREA

This paper presents the results of continuous monitoring of 11 pollution indicators of municipal wastewater that were discharged into the natural recipient (the sea) at three locations in the Split area during four years (2006-2009). Experimental data were analyzed by basic statistical methods for determination of mean and median values, standard deviations, minimal and maximal value of the measured parameters and their mutual correlation coefficients, normality test for all parameters and by different chemometric methods, such as cluster analysis (CA), factor analysis (FA) and principal component analysis (PCA). Multivariate statistical techniques for evaluation and interpretation of large complex data sets used in this study provide better insight into the information about water quality and make a decision concerning the design of monitoring network for effective management of water resources much easier

Correction: Škugor Rončević, I.; et al. Effective and Environmentally Friendly Nickel Coating on the Magnesium Alloy. Metals 2016, 6, 316

The following changes have been made to the published manuscript “Effective and Environmentally Friendly Nickel Coating on the Magnesium Alloy [...

Effective and Environmentally Friendly Nickel Coating on the Magnesium Alloy

The low density and good mechanical properties make magnesium and its alloys attractive construction materials in the electronics, automotive, and aerospace industry, together with application in medicine due to their biocompatibility. Magnesium AZ91D alloy is an alloy with a high content of aluminum, whose mechanical properties overshadow the low corrosion resistance caused by the composition of the alloy and the existence of two phases: α magnesium matrix and β magnesium aluminum intermetallic compound. To improve the corrosion resistance, it is necessary to find an effective protection method for the alloy surface. Knowing and predicting electrochemical processes is an essential for the design and optimization of protective coatings on magnesium and its alloys. In this work, the formations of nickel protective coatings on the magnesium AZ91D alloy surface by electrodeposition and chemical deposition, are presented. For this purpose, environmentally friendly electrolytes were used. The corrosion resistance of the protected alloy was determined in chloride medium using appropriate electrochemical techniques. Characterization of the surface was performed with highly sophisticated surface-analytical methods

Copper(II) ion selective PVC membrane electrode based on S,S\u27-bis(2-aminophenyl)ethanebis(thioate)

S,S\u27-bis(2-aminophenyl)ethanebis(thioate) (APhET) was synthesized and used as ion carrier in the preparation of copper(II) ion selective PVC membrane electrodes. The best performances were obtained by a membrane electrode with the composition: PVC as matrix (66 mg), APhET as ionophore (4 mg), o-NPOE as plasticizer (132 mg) and NaTBP as anionic additive (1/2 mole ratio in respect to APhET). This electrode exhibited a linear potential response to copper(II) in the concentration range 6.0 × 10−6 − 5.0 × 10−2 mol dm−3, with Nernstian slope of 29.5 mV/decade and detection limit down to 4 × 10−6 mol dm−3. It is suitable for copper(II) determination within pH between 4 and 7, and performs well over a period of 3 months. The electrode is selective for copper over a large number of metal ions, except Hg2+. No interference was noticed by chlorides and other examined anions. Described membrane electrode can be used in analytical measurements by direct potentiometry as well in potentiometric titration.</p

Electrochemical sensors and biosensors based on heterogeneous carbon materials

International audienceAn overview of the use of electrochemical sensors made from heterogeneous carbon materials (carbon paste electrodes, screen-printed carbon electrodes) in the field of food analysis is presented. Sensors for inorganic and organic analytes as well as biosensors are summarized

Effective and Environmentally Friendly Nickel Coating on the Magnesium Alloy

The low density and good mechanical properties make magnesium and its alloys attractive construction materials in the electronics, automotive, and aerospace industry, together with application in medicine due to their biocompatibility. Magnesium AZ91D alloy is an alloy with a high content of aluminum, whose mechanical properties overshadow the low corrosion resistance caused by the composition of the alloy and the existence of two phases: α magnesium matrix and β magnesium aluminum intermetallic compound. To improve the corrosion resistance, it is necessary to find an effective protection method for the alloy surface. Knowing and predicting electrochemical processes is an essential for the design and optimization of protective coatings on magnesium and its alloys. In this work, the formations of nickel protective coatings on the magnesium AZ91D alloy surface by electrodeposition and chemical deposition, are presented. For this purpose, environmentally friendly electrolytes were used. The corrosion resistance of the protected alloy was determined in chloride medium using appropriate electrochemical techniques. Characterization of the surface was performed with highly sophisticated surface-analytical methods