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Bulletin of the Chemists and Technologists of Bosnia and Herzegovina
Issue 48
Publication date: June 2017 |
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Table of contents
Influence of deposition parameters on pulsed laser deposition of K0.3MoO3 thin films Original Scientific Article
Đekić Maja, Salčinović Fetić Amra, Hrvat Kerim, Lozančić Matej
Abstract: Pulsed laser deposition (PLD) has become the most important technique for the production of new materials with complex stoichiometry and multilayered structures. In this paper we present parameters that influence the production of K0.3MoO3 (KBB) thin films by PLD. KBB is a quasi-one-dimensional (q-1D) conductor that exhibits transition to a new ground state of charge density wave (CDW) below a transition temperature Tp. It is considered to be a “canonical“ CDW system and its properties have been extensively researched in bulk. In recent years, production of KBB thin films has enabled investigation of CDW properties in the conditions of reduced dimensionality. Choice of deposition parameters highly influences production of the films and therefore it is essential to investigate it in order to obtain high quality films. This investigation enables one to determine optimal conditions for the production of KBB thin films by PLD.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 1-4.
The Correlation between C-Reactive Protein and Regulation of Glycemia in Type-2 Diabetic Patients Original Scientific Paper
Mandal Šaćira, Čaušević Adlija
Abstract: Inflammation plays a significant role in the development of Type 2 diabetes mellitus (T2D). Studies have indicated that C-reactive protein (CRP) as inflammatory marker is an important risk factor for insulin resistance (IR) and T2D. The purpose of this study was to determine concentrations of fasting C-reactive protein, glucose, and hemoglobin A1c (HbA1c) in a total of 40 adults with Type 2 diabetes (40-60 years of the age) and 40 healthy subjects as control group (the same ages). We found that C–reactive protein concentrations in diabetic subjects were higher than those in control group. Also, our results have shown the significant association between CRP and hemoglobin A1c levels (p<0.05) and positive association with glucose concentrations (p>0.05) in T2 diabetics. A negative, but not significant correlation of CRP with glucose and hemoglobin A1c levels was demonstrated in controls. Therefore, our findings suggest an association between glycemic control and systematic inflammation in people with diagnosed diabetes.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 5-8.
Inhibitory effects of selected phenolic acids on the oscillations of the Briggs-Rauscher reaction Original Scientific Paper
Džomba Emina, Gojak-Salimović Sabina
Abstract: Phenolic acids are secondary metabolites of aromatic plant that possess prominent antioxidant activity. When an antioxidant is added to an active oscillating Briggs-Rauscher reaction mixture, there is an immediate cessation of the oscillations, an inhibition time that linearly depends on the concentration of the antioxidant added, and a subsequent regeneration of oscillations. In this study, the effects of concentration of the ethanol solutions of selected phenolic acids (gallic, caffeic, chlorogenic, rosmarinic, p-coumaric and m-coumaric acids) on the oscillatory system Briggs-Rauscher reaction were investigated. The reaction was performed in a constantly stirred reactor, with accurately defined concentrations of reactants, at constant temperature of 25°C. Flow oscillations in the Briggs-Rauscher reaction mixture were monitored as a change in potential between the platinum electrode and silver/silver chloride reference electrode. Relative antioxidant activities of phenolic acids were determined in three ways on the basis of inhibition times. The obtained results showed that the gallic and p-coumaric acids have much less antioxidant activity than the caffeic, chlorogenic and rosmarinic acids. The ability to inhibit oscillations of the Briggs-Rauscher reaction mixture is not showed for m-coumaric acid.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 9-14.
Electrochemical treatment of leather industry wastewater Original Scientific Paper
Halilović Namir, Krdžalić Edin, Bašić Azra, Dacić Minela, Avdić Nurudin
Abstract: Leather industry wastewater is contaminated with bacteria including Escherichia Coli. In this paper, results obtained from analysis of leather industry wastewater samples with use of copper electrodes are presented and compared with the results of use of aluminum electrodes and mixed metal oxide electrodes. In all experiments the same materials were used as anode and cathode except the two last where anode of the mixed metal oxides and steel cathode was used. Electrodes with platinum group metals or their oxides as active coatings are generally the best suited for electrochemical water disinfection. After 7 min of electrolysis at only 0,018 A/dm2, Cl- was reduced using both tested electrodes, the efficiency of microorganisms removal followed the order: Cu > Al. The electrochemical treatment of wastewater resulted in the production of chlorine gas and hypochlorite, which is microorganisms deactivator. Also, electrocoagulation by aluminum anode was used for water purification to reduce all pollutants, including chlorides and microorganisms.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 15-20.
The determination of iron levels in Menthae tea (Mentha piperita L.) Original Scientific Paper
Mandal Šaćira, Keškić Nejra, Marevac Naida
Abstract: Menthae tea (Mentha piperita L.) is one of the most widely consumed herbal teas. This tea is recognized as a drink that may have several health benefits, primarily due to the presence of nutritional elements especially essential micro and ultramicro elements. In this study, we investigated the content of iron in mentha tea samples found in a local market in Sarajevo. The preparation of the samples was done by dry digestion in triplicate while levels of iron were analyzed by spectrophotometry. The amounts of iron were ranged from 275.6 mg Fe/kg to 354.6 mg Fe/kg. The used spectrophotometric method is simple and sensitive method that can be applied for the determination of total Fe content in plant material.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 21-26.
Contribution to Knowledge of Contains on Peridotite Rocks of the Krivaja-Konjuh Ophiolitic Complex (Massif) Original Scientific Paper
Operta Mevlida
Abstract: Krivaja-Konjuh ultramafic complex is mainly constructed of ultramafic rocks associated with different varieties of igneous rocks (gabbro, dolerite, diabase, spilite, keratophyres, granitoids) and metamorphic rocks (amphibolites, amphibolite schists and eclogites). This paper presents results of mineralogical and chemical analysis of ultramafite rocks (peridotite-lherzolites) samples in the southern part of Krivaja-Konjuh massif. The samples were examined optically, by using method of X-ray fluorescence spectroscopy and electron microprobe method. Optical results showed that lherzolites have uniform textural characteristics and mineral composition. Results of chemical studies on these rocks demonstrated modal composition with high content of MgO, low content of CaO and high content of MgO:FeO (about 5 and up). Based on CIPW normative system, their composition is uniform with a very small variation in the content of diopside, with a slightly larger variation in the content of olivine. The rhombic pyroxene in composition correspond to enstatite and monoclinic pyroxenes are diopside by the composition . Spinel in peridotites are Al spinels and Al chromium spinels.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 27-34.
Application of Aloe Vera as Green Corrosion Inhibitor for Aluminum Alloy Types AA8011 and AA8006 in 3,5% NaCl Original Scientific Paper
Bikić Farzet, Kasapović Dejana, Delijić Kemal, Radonjić Dragan
Abstract: This paper presents testing data on application possibilities of Aloe Vera as green corrosion inhibitor for aluminum alloy types AA8011 and AA8006 in 3.5% NaCl. Electrochemical DC linear polarization method has been used in the first phase of testing process, with the goal of determining the optimal concentration of Aloe Vera as inhibitor of mentioned alloys in 3.5% NaCl, by polarization resistance value. During first testing process, only one aluminum alloy type AA8011 was used. By adding the inhibitor in 3.5% NaCl, the polarization resistance increases, and the highest result was recorded in Aloe Vera concentration of 5 cm3dm-3. During second phase of testing, the inhibition affect of optimal Aloe Vera concentration was tested for aluminum alloy type AA8011 and AA8006 in 3.5% NaCl by curves of Taffel extrapolation method. The results of conducted tests show that Aloe Vera in concentration of 5 cm3dm-3 can be used as green inhibitor for aluminum alloys type AA8011 and AA8006 of the Al-Fe-Si-Mn system, in 3.5% NaCl at room temperature (20 ± 2 ºC). All tested samples of aluminum alloy in 3.5% NaCl solution with the presence of inhibitor show significant shifting of Open Circuit Potential (EOCP) towards positive values in respect with Open Circuit Potential (EOCP) of treated aluminum alloy samples in 3.5% NaCl solution without inhibitor presence. Likewise, most of the samples treated in 3.5% NaCl solution with the presence of inhibitor lead to decrease of corrosion current density in relation to samples tested in 3.5% NaCl solution without inhibitor presence.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 35-40.
Zn-Ni alloy coating made of chloride electrolyte Original Scientific Paper
Dautbašić Adem, Ćatić Sead, Ćatić Osman
Abstract: Electrodeposition coating based on Zn-Ni alloys was made of chloride electrolyte which contains 142.56 g/dm3 NiCl2x6H2O; 109.03 g/dm3 ZnCl2; 30.9 g/dm3 H3BO3; 223.65 g/dm3 KCl; 40.99 g/dm3 CH3COONa. As the result coatings of different sizes and different amount of Ni in each coating were prepared. The samples were tested in salt spray chambers according to BS EN ISO 10289:2001standard. The best results showed coatings which were over 10 μm thick and which contained up to 15% of Nickle. There were no signs of corrosion even after 2160 hours of being in salt spray chambers.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 41-44.
Electrodeposition of polyaniline films on stainless steel and their voltammetric behavior in corrosive environments Original Scientific Paper
Gutić Sanjin, Cacan Merzuk, Korać Fehim
Abstract: Polyaniline films were electrodeposited on the stainless steel substrates from aniline solutions with different acids. Kinetic of the film growth is discussed in terms of corrosion behavior of steel substrates in pure acids. Wide passive region in sulfuric and phosphoric acid enables initial oxidation of aniline and consequent deposition of polymer, without concurrent dissolution of alloy. On the other hand, in hydrochloric acid substrates actively dissolute at potentials necessary for aniline oxidation. However, formation of polymeric deposits is possible even in this case, probably due to the inhibition effect of aniline or oligoanilines formed during initial periods of anodic polarization. All deposited films exhibit electroactive behavior in low pH medium, while totally lose their ability for redox transitions in higher pH.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 45-50.
Many roles of melatonin: diversity and complexity of reaction pathways Review
Galijašević Semira
Abstract: Melatonin (N-acetyl-5-methoxy tryptamine) is well known as a free radical scavenger and antioxidant involved in different biological and physiological regulation such as modulation of circadian rhythms, seasonal reproduction, retinal physiology and sleep regulation. Synthetic melatonin is available commercially, and its supplements have been used clinically to treat a variety of medical conditions such as jet lag, shift work and sleep disorders. Recent studies demonstrated that melatonin serves as an inhibitor of myeloperoxidase (MPO) under physiological-like conditions. Melatonin-dependent inhibition of MPO occurred with a wide range of concentrations that span various physiological and supplemental ranges. Myeloperoxidase is enzyme involved in leukocyte-mediated host defenses but plays a pathogenic role during chronic inflammatory conditions. MPO levels implicate inflammation in the walls of coronary arteries, which in turn, may indicate a risk for heart disease or heart attack. Thus, supplementary concentrations of melatonin can influence physiological and pathophysiological role of MPO. In addition, MPO modulates nitric oxide production, so melatonin can indirectly affects nitric oxide concentration. Amounting evidence shows new emerging role of melatonin and its metabolites beyond the classic one. This review focuses on newly discovered mechanistic pathways of melatonin activity that has to be taken into consideration when discussing pharmacological uses of melatonin.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 48, 51-58.
