Preparation of NiO supported carbon paste electrode for sensitive and selective determination of Gallic acid in plant samples

In this work, nickel oxide (NiO) nanoparticles were synthesized by the chemical coprecipitation method and used for modification of the carbon paste electrode for GA detection and determination. Morphological properties of prepared material were investigated using ICP-OES (inductively coupled plasma–optical emission spectrometry), XRD (X-ray diffraction), SEM and TEM (Scanning and Transmission Electron Microscopy). The electrochemical properties of the prepared electrode and the behavior of GA over the modified electrode were examined using CV (Cyclic Voltammetry), EIS (Electrochemical impedance spectroscopy), and SWV (Square Wave Voltammetry)

Fabrication of bismuth-oxychloride supported carbon paste electrode for sensitive Quinine sensing

Quinine is a natural white crystalline cinchona alkaloid that belongs to the aryl amino alcohol group of drugs, and it has antipyretic (fever reducing), antimalarial, analgesic, anti-inflammatory properties and a bitter taste. Today, quinine is considered as the best antimalarial drug since it is chiefly used in the treatment of falciparum malaria resistant to other antimalarials. Quinine is preferred where the disease has become highly resistant to other antimalarial drugs [1]. Quinine has a low therapeutic index, and it is potentially toxic and causes several side effects including nausea, blurred vision, diarrhea, abdominal pain, headache, fever, renal failure and asthma [2]. Since quinine is widely used as a bittering agent in tonic type drinks, a sensitive and discriminatory system for the discovery of quinine is essential for human health. In this work, a modified bismuth-oxychloride (BiOCl) carbon paste electrode was prepared for the detection of quinine. BiOCl nanoparticles were synthesized by the chemical coprecipitation method. The electrochemical properties of quinine at this electrode were investigated by cyclic voltammetry (CV), square wave voltammetry (SWV), and differential pulse voltammetry (DPV). In addition, electrochemical impedance spectroscopy (EIS), inductively coupled plasma–optical emission spectrometry (ICP-OES), transmission and scanning electron microscopy (TEM and SEM) and X-ray diffraction (XRD) were used to characterize the synthesized materials. The prepared electrode showed better electrocatalytic response than the bare carbon paste electrode. After square wave voltammetry (SWV) optimization, the electrode showed a wide linear working range from 20 to 200 μM at pH 6 of Britton–Robinson buffer solution (BRBS) as the supporting electrolyte. The excellent selectivity of the proposed method, with good repeatability and reproducibility, strongly suggests a potential application of the method for the determination of quinine in pharmaceuticals. The practicality with good recoveries indicates that the morphology of the materials is closely related to other parameters, which in turn suggests that the developed approach can provide a cost effective, rapid, selective, and sensitive method for quinine monitoring

The Inhibitive effect of ethanolamine on corrosion behavior of aluminium in NaCl solution saturated with CO2

In this study, the inhibitive effect of ethanolamine on corrosion behavior of aluminium was investigated in 3 wt. % NaCl solution, saturated with CO2. All the experiments were carried out at 20 °C. Ethanolamine was added at different concentrations between 1 mM and 8 mM. In order to determine the corrosion inhibition efficiency of investigated inhibitor and the optimal concentration of inhibitor that provides the lowest corrosion of aluminium, the open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), linear sweep voltametry (LSV) measurements, weight loss measurements as well as scanning electron microscopy technique (SEM) were performed. The electrochemical study and weight loss measurements indicated that the minimum corrosion rate and maximum inhibition efficiency was detected for concentration of 5 mM of ethanolamine, as well as the ethanolamine did not change the mechanism of aluminium dissolution. The adsorption of ethanolamine was found to obey Frumkin adsorption isotherm at concentrations up to 5 mM, but further increase in concentration was found to deviate from Frumkin adsorption isotherm. The calculated value for interaction parameter a indicates attractive lateral interactions in the adsorbed inhibitor layer. The obtained value of standard free energy of adsorption, ∆Gads θ , confirms that the adsorption process is favorable, spontaneous physisorption process

Abudance of lanthanoids and actinoids in different soil types in Serbia and potential of fungi Macrolepiota procera (scop.) singer for their accumulation

U okviru ove doktorske disertacije određena je zastupljenost lantanoida, skandijuma i itrijuma (elementi retkih zemalja), urana i torijuma (prirodno najzastupljenijih aktinoida) kao i određenih mikroelemenata (olova, vanadijuma, rubidijuma i srebra) u uzorcima zemljišta različitog tipa sa područja Srbije, ispitana je njihova distribucija u zemljištu i procenjena je sposobnost gljive Macrolepiota procera da ih apsorbuje i akumulira u svom plodonosnom telu.Uzorci zemljišta uzeti su sa više lokaliteta na planini Goč i iz šuma u okolini Trstenika. Ukupan sadržaj ispitivanih elemenata u zemljištu određen je nakon digestije uzoraka carskom vodom. U cilju definisanja raspodele elemenata po zemljišnim frakcijama (lako izmenjiva, reducibilna, oksidabilna i rezidualna) i procene njihove biodostupnosti primenjena je BCR (Commission of the European Communities Bureau of Reference) sekvencijalna ekstrakciona procedura. Sadržaj ispitivanih elemenata određen je i u šeširu i dršci plodonosnog tela M. procera nakon mikrotalasne digestije. Za kvantifikaciju elemenata u pripremljenim uzorcima korišćena je metoda indukovano spregnuta plazma - masena spektrometrija (ICP-MS). Primenjena metoda je verifikovana korišćenjem standardnih referentnih materijala.U ispitivanim uzorcima zemljišta, od lantanoida u najvećoj koncentraciji bio je zastupljen cerijum a zatim neodijum i lantan, dok su u najmanjoj koncentraciji bili zastupljeni lutecijum i tulijum. Sadržaji skandijuma, itrijuma, urana i torijuma u zemljištu centralne Srbije odgovaraju vrednostima za nekontaminirana zemljišta, bez izrazitog antropogenog uticaja. Elementi retkih zemalja i aktinoidi dominantno su povezani sa rezidualnom frakcijom zemljišta što ukazuje na njihovu malu mobilnost i nisku biodostupnost pri uobičajenim uslovima životne sredine. Različita zastupljenost elemenata retkih zemalja u zemljištu u zavisnosti od njegovog tipa i geografskog porekla, omogućava diferencijaciju zemljišta prema lokaciji, što je potvrđeno metodom multivarijantne analize.U cilju utvrđivanja mehanizama usvajanja ispitivanih elemenata u plodonosno telo M. procera, izračunate su vrednosti biokoncentracionih i translokacionih faktora. M. procera ne poseduje potencijal akumulacije elemenata retkih zemalja i aktinoida. Sa druge strane, u zavisnosti od lokaliteta uzorkovanja, uočena je razlika u koncentracijama ovih elemenata u plodonosnim telima gljive, što ukazuje na uticaj karakteristika zemljišta na potencijal apsorpcije i akumulacije.Within this doctoral dissertation, the content of lanthanoids, scandium and yttrium (rare earth elements), uranium and thorium (the most abundant naturally occuring actinoids) as well as certain microelements (lead, vanadium, rubidium and silver) was determined in different types of soil from Serbia, together with the examination of their distribution in the soil and the ability of the fungus Macrolepiota procera to absorb and accumulate these elements in its fruiting body has been assessed.Soil samples were collected at multiple locations on Mount Goč and from forests around Trstenik. The total content of the examined elements in the soil was determined after aqua regia digestion of soil samples. In order to define the distribution of elements in soil fractions (easily exchangeable, reducible, oxidizable and residual) and to assess their bioavailability the BCR (Commission of the European Communities Bureau of Reference) sequential extraction procedure was applied. The content of the examined elements was determined in the parts of the fruiting body of M. procera (in the stipe and cap), after microwave digestion. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the elements in the prepared samples. The applied method was verified using standard reference materials.In the examined soil samples, from lanthanoids, cerium was present in the highest concentration, followed by neodymium and lanthanum, while lutetium and thulium were present in the lowest concentration. The contents of scandium, yttrium, uranium and thorium in the soil of central Serbia correspond to the values for uncontaminated soils, without a pronounced anthropogenic impact. Rare earth elements and actinoids are predominantly associated with the residual soil fraction indicating their low mobility as well as bioavailability under normal environmental conditions. The different content of rare earth elements in the soil, depending on its type and geographical origin, enables the differentiation of soil according to location, which is confirmed by the method of multivariate analysis.In order to examine the assimilation mechanisms of the examined elements into the fruiting body of the M. procera, the values of bioconcentration and translocation factors were calculated. M. procera does not have the potential for the accumulation of rare earth elements and actinoids. On the other hand, depending on the sampling location, a difference in the concentrations of these elements in the fruiting bodies of the fungus was observed, which indicates the influence of the soil characteristics on the absorption and accumulation potential

A novel carbon paste electrode modified by NP-Y2O3 doped with the g-C3N4 for sensitive electrochemical detection of herbicide bentazone in river, soil, and vegetable samples

Pesticides have a significant role in the world food chain in the setting of rising agricultural output demand and rising climate change impacts on agricultural productivity. Pesticide contamination across the world is not just a pressing issue; it also has the potential to get worse, for instance, because of movements in global production to nations with laxer environmental regulations [1]. In this work, we have designed a new electrochemical sensor for detecting bentazone (BZT) by using NP-Y2O3/g-C3N4 modified carbon paste electrode (CP). For the first time, the Pechini method was employed to synthesize the Y2O3 nanocomposite. The nanomaterial was characterized by Xray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). In order to create an analytical technique for identifying and measuring BZT, the electrocatalytic characteristics of the suggested Y2O3/g-C3N4 modified CP electrode were examined. Using the CV and DPV approaches, the electrochemical behavior of BZT at the Y2O3/gC3N4 sensor was investigated. The proposed electrochemical sensor exhibited excellent electrochemical response toward BZT with a wide linear range of 1 to 100 µM, with a detection limit of 0.68 µM. The effect of possible interfering agents is negligible, confirming the good selectivity of the method. The sensor also displayed excellent sensitivity, reproducibility, and stability. Additionally, the Y2O3/g-C3N4 sensor was utilized for the detection of BZT in water and soil samples, and also in red and green pepper samples, and it exhibited good recovery results

Triangle-Shaped Cerium Tungstate Nanoparticles Used to Modify Carbon Paste Electrode for Sensitive Hydroquinone Detection in Water Samples

In this study, we propose an eco-friendly method for synthesizing cerium tungstate nanoparticles using hydrothermal techniques. We used scanning, transmission electron microscopy, and X-ray diffraction to analyze the morphology of the synthesized nanoparticles. The results showed that the synthesized nanoparticles were uniform and highly crystalline, with a particle size of about 50 nm. The electrocatalytic properties of the nanoparticles were then investigated using cyclic voltammetry and electrochemical impedance spectroscopy. We further used the synthesized nanoparticles to develop an electrochemical sensor based on a carbon paste electrode that can detect hydroquinone. By optimizing the differential pulse voltammetric method, a wide linearity range of 0.4 to 45 µM and a low detection limit of 0.06 µM were obtained. The developed sensor also expressed excellent repeatability (RSD up to 3.8%) and reproducibility (RSD below 5%). Interferences had an insignificant impact on the determination of analytes, making it possible to use this method for monitoring hydroquinone concentrations in tap water. This study introduces a new approach to the chemistry of materials and the environment and demonstrates that a careful selection of components can lead to new horizons in analytical chemistry

Abudance of lanthanoids and actinoids in different soil types in Serbia and potential of fungi Macrolepiota procera (scop.) singer for their accumulation

U okviru ove doktorske disertacije određena je zastupljenost lantanoida, skandijuma i itrijuma (elementi retkih zemalja), urana i torijuma (prirodno najzastupljenijih aktinoida) kao i određenih mikroelemenata (olova, vanadijuma, rubidijuma i srebra) u uzorcima zemljišta različitog tipa sa područja Srbije, ispitana je njihova distribucija u zemljištu i procenjena je sposobnost gljive Macrolepiota procera da ih apsorbuje i akumulira u svom plodonosnom telu. Uzorci zemljišta uzeti su sa više lokaliteta na planini Goč i iz šuma u okolini Trstenika. Ukupan sadržaj ispitivanih elemenata u zemljištu određen je nakon digestije uzoraka carskom vodom. U cilju definisanja raspodele elemenata po zemljišnim frakcijama (lako izmenjiva, reducibilna, oksidabilna i rezidualna) i procene njihove biodostupnosti primenjena je BCR (Commission of the European Communities Bureau of Reference) sekvencijalna ekstrakciona procedura. Sadržaj ispitivanih elemenata određen je i u šeširu i dršci plodonosnog tela M. procera nakon mikrotalasne digestije. Za kvantifikaciju elemenata u pripremljenim uzorcima korišćena je metoda indukovano spregnuta plazma - masena spektrometrija (ICP-MS). Primenjena metoda je verifikovana korišćenjem standardnih referentnih materijala. U ispitivanim uzorcima zemljišta, od lantanoida u najvećoj koncentraciji bio je zastupljen cerijum a zatim neodijum i lantan, dok su u najmanjoj koncentraciji bili zastupljeni lutecijum i tulijum. Sadržaji skandijuma, itrijuma, urana i torijuma u zemljištu centralne Srbije odgovaraju vrednostima za nekontaminirana zemljišta, bez izrazitog antropogenog uticaja. Elementi retkih zemalja i aktinoidi dominantno su povezani sa rezidualnom frakcijom zemljišta što ukazuje na njihovu malu mobilnost i nisku biodostupnost pri uobičajenim uslovima životne sredine. Različita zastupljenost elemenata retkih zemalja u zemljištu u zavisnosti od njegovog tipa i geografskog porekla, omogućava diferencijaciju zemljišta prema lokaciji, što je potvrđeno metodom multivarijantne analize. U cilju utvrđivanja mehanizama usvajanja ispitivanih elemenata u plodonosno telo M. procera, izračunate su vrednosti biokoncentracionih i translokacionih faktora. M. procera ne poseduje potencijal akumulacije elemenata retkih zemalja i aktinoida. Sa druge strane, u zavisnosti od lokaliteta uzorkovanja, uočena je razlika u koncentracijama ovih elemenata u plodonosnim telima gljive, što ukazuje na uticaj karakteristika zemljišta na potencijal apsorpcije i akumulacije.Within this doctoral dissertation, the content of lanthanoids, scandium and yttrium (rare earth elements), uranium and thorium (the most abundant naturally occuring actinoids) as well as certain microelements (lead, vanadium, rubidium and silver) was determined in different types of soil from Serbia, together with the examination of their distribution in the soil and the ability of the fungus Macrolepiota procera to absorb and accumulate these elements in its fruiting body has been assessed. Soil samples were collected at multiple locations on Mount Goč and from forests around Trstenik. The total content of the examined elements in the soil was determined after aqua regia digestion of soil samples. In order to define the distribution of elements in soil fractions (easily exchangeable, reducible, oxidizable and residual) and to assess their bioavailability the BCR (Commission of the European Communities Bureau of Reference) sequential extraction procedure was applied. The content of the examined elements was determined in the parts of the fruiting body of M. procera (in the stipe and cap), after microwave digestion. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the elements in the prepared samples. The applied method was verified using standard reference materials. In the examined soil samples, from lanthanoids, cerium was present in the highest concentration, followed by neodymium and lanthanum, while lutetium and thulium were present in the lowest concentration. The contents of scandium, yttrium, uranium and thorium in the soil of central Serbia correspond to the values for uncontaminated soils, without a pronounced anthropogenic impact. Rare earth elements and actinoids are predominantly associated with the residual soil fraction indicating their low mobility as well as bioavailability under normal environmental conditions. The different content of rare earth elements in the soil, depending on its type and geographical origin, enables the differentiation of soil according to location, which is confirmed by the method of multivariate analysis. In order to examine the assimilation mechanisms of the examined elements into the fruiting body of the M. procera, the values of bioconcentration and translocation factors were calculated. M. procera does not have the potential for the accumulation of rare earth elements and actinoids. On the other hand, depending on the sampling location, a difference in the concentrations of these elements in the fruiting bodies of the fungus was observed, which indicates the influence of the soil characteristics on the absorption and accumulation potential

Biosurveillance of Technocracy in a Pandemic

Tehnokracija je ekonomska i društvena kontrola zajednice i pojedinca koja je primjetna i na Istoku i Zapadu. Tehnokratsko doba podrazumijeva postupno stvaranje kontroliranog i usmjerenog društva kojim dominira elita, čiji zahtjev za političku moć počiva na navodno superiornom znanstvenom iskustvu. Tehnokraciju ne interesira politička ideologija, već samo najbolja i najučinkovitija rješenja problema, ističući da se znanosti treba podčiniti jer nam daje moć nad prirodom, dok moć u potpunosti potječe iz tehnike. Tehnologija postaje više biološka, dok biologija postaje tehnološka. Bionadzor u pandemiji u sebi sadrži apstraktne forme panoptikuma, kao kategorije moći s disciplinskom funkcijom u cilju nametanja određenog ponašanja i iskorištavanja moći ljudskog kapitala koji obuhvaća biopolitičko tijelo s jedne strane, u Foucaultovoj perspektivi, i društvenu kontrolu s druge strane, kako je vidi Gilles Deleuze. U kapitalizmu bionadzora, kapital korporacija u sebi objedinjuje kontroliranu, disperzivnu, sveobuhvatnu i sveprisutnu umreženu moć. Bionadzor nad pojedincima ne provodi se samo kroz ideologije već i kroz svijest – i u tijelu i nad tijelom u spektaklu straha i medijskog programiranja, kroz sve aspekte društvenog života. Radom se dokazuje da je tehnokracija ovladala svakim aspektom bionadzora u društvu kroz mehanizme praćenja i usmjeravanja ponašanja pojedinaca, te njegovoj modifikaciji, predviđanju i kontroli. Kroz bionadzor tehnokracija teži stvaranju poslušnog podanika i dominaciji privatne sfere domenama javnog interesa. Tehnokracija je ovladala suverenom moći koja traži poslušnost, disciplinskom koja zahtjeva pokornost i regulativnom koja zahtjeva pokoravanje i podčinjavanje zdravlju stanovništva kroz organizirani sustav psihološke intervencije i zakonodavnih normi.Technocracy is the economic and social control of the community and individuals that is noticeable in both the East and the West. The technetronic era involves the gradual appearance of a more controlled and directed society. Such a society would be dominated by an elite whose claim to political power would rest on allegedly superior scientific know-how. Technocrats have never cared about political ideology, but rather only about the best and most efficient solutions to problems. Science is to be admired because it gives us power over nature, and the power comes wholly from technique. Technology becomes more biological, while biology becomes more technological. In the pandemic, biosurveillance contains abstract forms of the panopticon, as a category of power with a disciplinary function aimed at imposing certain behavior and exploiting the power of human capital, which includes the biopolitical body on the one hand, in Foucault’s perspective, and social control, as seen by Gilles Deleuze, on the other. In biosurveillance capitalism, corporate capital brings together controlled, dispersive, comprehensive, and ubiquitous networked power. Biosurveillance of individuals is not only carried out through ideologies but also through consciousness – both in and over the body in the spectacle of fear and media programming, through all aspects of social life. The article proves that technocracy has possessed every aspect of biosurveillance in society because it has gained instrumental power that tends to instrumentalize behavior, modification, prediction, and control. Through biosurveillance, technocracy tends to create obedient subjects and dominate the private sphere by domains of public interest. Technocracy has controlled the sovereign power that demands obedience, the disciplinary power that demands submission, and the regulative power that demands obedience and submission to the health of the class through an organized system of psychological intervention and legislative norms

Kapacitet lokalne samouprave da poboljša poslovno okruženje: Dokazi iz Srbije

The aim of this paper is to draw attention on the need to strengthen institutional cooperation between local self-governments and the business community. The paper analyses the ability of socio-economic councils in Serbia, as a part of local governments, to improve the business environment and indicators of social status at the local level. In addition to socio-economic councils, this analysis includes the departments, divisions and offices for local economic development and their responsibilities. The results in the paper has been generated using descriptive statistics, Chi-Square test, t-test and regression analysis, based on the analysis of primary data collected in empirical research on 55 municipalities in Serbia. The fundamental results obtained using the stated analysis is that socio-economic councils have positive impact on the social and economic development in the survived municipalities. Finally, the basic conclusion from the executed research is that size of the municipality is not a limiting factor for the establishment of the socio-economic councils and their functionality.Cilj rada je skrenuti pozornost na potrebu za jačanjem institucionalne suradnje između lokalne samouprave i poslovne zajednice. Rad analizira sposobnost socioekonomskih savjeta u Srbiji, kao sastavnog dijela tijela lokalne samouprave, da unaprijedi poslovno okruženje i indikatore socijalnog statusa na lokalnoj razini. Pored socio-ekonomskih savjeta, analizom su obuhvaćeni odjeli i uredi za lokalni ekonomski razvoj i njihove nadležnosti. Rezultati istraživanja su generirani primjenom deskriptivne statistike, Hi kvadrat testa, t-testa i regresijske analize, a na temelju primarno prikupljenih podataka u empirijskom istraživanju na uzorku od 55 općina u Srbiji. Najznačajniji rezultat dobiven primjenom navedenih analiza je da socio-ekonomski savjeti imaju pozitivan utjecaj na socijalni i ekonomski razvoj u promatranim općinama. Na kraju, osnovni zaključak provedenog istraživanja je da veličina općina nije limitirajući faktor za osnivanje socio-ekonomskih savjeta i njihovu funkcionalnost