Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 13 of 13
Full-Text Articles in Physical Sciences and Mathematics
Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak
Turkish Journal of Chemistry
The chromium speciation procedure was optimized using magnetic polyaniline nanoparticles (Fe3O4@PANI NPs) solid-phase extraction coupled with microsampling injection-flame atomic absorption spectrometry (MIS-FAAS). Chromium speciation was successfully achieved by Fe3O4@PANI NPs at pH 8.0. The recoveries obtained for Cr(III) and Cr(VI) were above 95% and under 5%, respectively. Recoveries of over 95% for Cr(III) from 40.0 mL of the sample were obtained using 25 mg Fe3O4@PANI NPs and 500 µL of 0.2% (w/v) thiourea (TU) solution prepared in 2 mol L–1 HCl as eluent. Total chromium as Cr(III) was extracted quantitatively after reducing the Cr(VI) to Cr(III). The linear range, detection …
Supramolecular Solvent-Based Microextraction For The Preconcentration Of Pb2+ Andcd2+ Prior To Spectrophotometric Detection, Huma Zafar, Faheem Shah, Rafaqat Ali Khan, Asad Muhammad Khan, Jan Nisar, Bushra Ismail
Supramolecular Solvent-Based Microextraction For The Preconcentration Of Pb2+ Andcd2+ Prior To Spectrophotometric Detection, Huma Zafar, Faheem Shah, Rafaqat Ali Khan, Asad Muhammad Khan, Jan Nisar, Bushra Ismail
Turkish Journal of Chemistry
Supramolecular solvent-based dispersive liquid-liquid microextraction technique has been developed as a preconcentration tool for the determination of trace level of Pb2+ and Cd2+. Dodecanol dispersed in tetrahydrofuran has been utilized as a supramolecular-solvent system for the extraction of analytes prior to their quantitative determination with graphite furnace atomic absorption spectrophotometer. Both Pb2+ and Cd2+, which were efficiently extracted by supramolecular solvent system, were complexed with dithizone followed by the addition of supramolecular solvent. The experimental variables that could possibly influence the extraction efficiency, i.e. pH value, temperature, sample volume, centrifugation time, rate of centrifugation, ionic strength, etc. were subjected to …
Schiff Base Functionalized Silica Gel For Simultaneous Separation And Preconcentration Of Cu(Ii), Ni(Ii), And Cd(Ii) In Pharmaceuticals And Water Samples, Feyzullah Tokay, Sema Bağdat
Schiff Base Functionalized Silica Gel For Simultaneous Separation And Preconcentration Of Cu(Ii), Ni(Ii), And Cd(Ii) In Pharmaceuticals And Water Samples, Feyzullah Tokay, Sema Bağdat
Turkish Journal of Chemistry
A method for separation and preconcentration of Cu(II), Ni(II), and Cd(II) using N-N'-bis(5-methoxsalicylidene)-2-hydroxy-1,3-propanediamine modified silica gel was improved for aqueous samples and pharmaceuticals. Determination of the analytes was achieved by inductively coupled plasma optic emission spectrometry. The experimental conditions including pH value, sample volume, eluent type and volume, sorbent mass, sample, and eluent flow rates were optimized with univariate and multivariate optimization tools. The relative standard deviations of the method were 2.9% for Cu(II), 3.0% for Ni(II), and 3.3% for Cd(II) with recovery values between 98.8 ± 3.2-101.5 ± 3.0%. The limits of detection were found to be 62.4, 39.5, …
Spectrophotometric Detection Of Rhodamine B In Tap Water, Lipstick, Rouge, And Nail Polish Samples After Supramolecular Solvent Microextraction, Nebi̇ye Özkantar, Mustafa Soylak, Mustafa Tüzen
Spectrophotometric Detection Of Rhodamine B In Tap Water, Lipstick, Rouge, And Nail Polish Samples After Supramolecular Solvent Microextraction, Nebi̇ye Özkantar, Mustafa Soylak, Mustafa Tüzen
Turkish Journal of Chemistry
A simple and sensitive supramolecular solvent-based dispersive liquid--liquid microextraction method was described for the separation/preconcentration and spectrophotometric detection of rhodamine B. The microextraction method, which was realized at ambient temperature for the detection of rhodamine B, was carried out by using supramolecular solvents such as tetrahydrofuran and decanoic acid. The method was based on analyses of rhodamine B by using UV-Vis spectrophotometry at 558 nm. The influences of some parameters such as pH, sample volume, eluent solutions, centrifugation time, and ultrasonic bath time were optimized. The effects of various matrix ions were also investigated. Moreover, the limit of detection and …
Simple And Rapid Voltammetric Determination Of Boron In Water And Steel Samples Using A Pencil Graphite Electrode, Lokman Li̇v, Nuri̇ Naki̇boğlu
Simple And Rapid Voltammetric Determination Of Boron In Water And Steel Samples Using A Pencil Graphite Electrode, Lokman Li̇v, Nuri̇ Naki̇boğlu
Turkish Journal of Chemistry
This paper presents a simple, rapid, and accurate voltammetric method for determination of boron in water and steel samples using a disposable pencil graphite electrode. The oxidation of Tiron in the boron-Tiron complex in phosphate buffer at pH 7.5 was measured as a response. Type and concentration of supporting electrolyte, pH, ionic strength, Tiron concentration, scan rate, step amplitude, pulse amplitude, and pencil grade were investigated as the parameters affecting the peak current. The limit of detection (3s) was estimated as 84 $\mu $g/L. The relative standard deviation of the method was 4.6 for 1 mg B/L (N = 7). …
Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu
Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu
Turkish Journal of Chemistry
A green and efficient protocol has been developed for the Pd(OAc)$_{2}$-catalyzed ligand-free Suzuki--Miyaura reaction of $N$-methyliminodiacetic acid (MIDA) boronates in water. In the presence of Pd(OAc)$_{2}$ as a catalyst and ($i$-Pr)$_{2}$NH as a base, the cross-coupling reactions of aryl bromides with aryl MIDA boronates proceeded smoothly in water without any surfactant, and various functional groups were tolerated under the optimized conditions.
Environmentally Green Synthesis Of Thioformamide Derivatives, Ali Ramazani, Sang Woo Joo, Fatemeh Zeinali Nasrabadi
Environmentally Green Synthesis Of Thioformamide Derivatives, Ali Ramazani, Sang Woo Joo, Fatemeh Zeinali Nasrabadi
Turkish Journal of Chemistry
Reactions of isocyanides with thioacids in water proceeded smoothly at room temperature and in neutral conditions to afford thioformylamide and thioformamide derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed.
Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu
Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu
Turkish Journal of Chemistry
This paper describes a sensitive and accurate adsorptive catalytic stripping voltammetric method for the determination of zineb (zinc ethylene-bis- dithiocarbamate) in tap water and tomato samples. The method is based on the reduction of adsorbed zineb at a hanging mercury drop electrode following its catalytic oxidation using peroxydisulfate as an oxidizing reagent. Chemical and instrumental parameters of the process were optimized. The catalytic mechanism of the reduction of zineb is discussed as well. The limits of detection (3 s) and quantification (10 s) and linear range of the method for accumulation time of 60 s were calculated as 8.1 nM, …
Palladium-Edta And Palladium-Edteh_4 Catalyzed Heck Coupling Reactions In Pure Water, Süleyman Gülcemal, Beki̇r Çeti̇nkaya
Palladium-Edta And Palladium-Edteh_4 Catalyzed Heck Coupling Reactions In Pure Water, Süleyman Gülcemal, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
Palladium-catalyzed Heck coupling reactions of styrene with bromoarene derivatives are carried out under aerobic conditions in water using water-soluble N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (EdteH_4) and ethylenediaminetetraacetic acid disodium salt (Na_2EDTA) as ligands. The effect of different bases, catalyst loading, and additives is also monitored. The olefination of bromoarenes with styrene affords the desired products in high yields. The Na_2PdCl_4-Na_2EDTA precatalyst system is also used for the preparative scale (50.0 mmol) synthesis of 4-acetyl-trans-stilbene and 4-styrylbenzaldehyde without a noticeable decrease in the activity. Recycling studies on the Na_2PdCl_4 - Na_2EDTA precatalyst system are also tested in the coupling of 4-bromoacetophenone with styrene.
Preconcentration Of Trace Elements On Amberlite Xad-4 Resin Functionalised With 1,2-Bis (O-Aminophenylthio) Ethane And Their Determination By Faas In Environmental Samples, Ömer Dalman, Volkan Numan Bulut, İsmai̇l Deği̇rmenci̇oğlu, Mehmet Tüfekçi̇
Preconcentration Of Trace Elements On Amberlite Xad-4 Resin Functionalised With 1,2-Bis (O-Aminophenylthio) Ethane And Their Determination By Faas In Environmental Samples, Ömer Dalman, Volkan Numan Bulut, İsmai̇l Deği̇rmenci̇oğlu, Mehmet Tüfekçi̇
Turkish Journal of Chemistry
The use of chemically modified XAD-4-1,2-bis (o-aminophenylthio) ethane chelating resin for preconcentrating Cr^{6+}, Mn^{2+}, Fe^{3+}, Co^{2+}, Cu^{2+}, Cd^{2+}, Zn^{2+}, Pb^{2+}, and Ni^{2+} was studied using flame atomic absorption spectrometry (FAAS) for metal monitoring in environmental samples. Cd^{2+}, Zn^{2+}, Pb^{2+}, and Ni^{2+} ions were quantitatively recovered at the rate of 96.0%, 101.0%, 101.0%, and 95.0%, respectively (RSD < 5%), from the studied solutions. The procedure is based on the retention of analytes on a short column of 1,2-bis (o-aminophenylthio) ethane-XAD-4 chelating resin from a buffered sample solution and subsequent elution with 1 M HNO_3. Various parameters, such as pH, eluent type, and concentration, flow rate of sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of the above-mentioned metal ions was about 6. The adsorption and batch capacity of adsorbent and loading half time (t_{1/2}) for Ni^{2+}, Zn^{2+}, Cd^{2+}, and Pb^{2+} were established. The limit of detection was 3.0 \mu g L^{-1} for Pb^{2+} and Ni^{2+}, 0.6 \mu g L^{-1} for Cd^{2+}, and 0.3 \mu g L^{-1} for Zn^{2+}. The validation of the procedure was carried out by analysis of certified reference materials and standard addition. The proposed enrichment method was applied to environmental samples from Trabzon.
Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n
Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n
Turkish Journal of Chemistry
The determination of fluoride in some environmental samples was performed using a fluoride ion-selective electrode. Fluoride concentrations were determined in drinking waters (from different provinces, districts and villages in Turkey), fruit juices, bottled water samples, toothpastes and tooth powders, liquors of Turkish coffee, coffee, linden, rose hip, and various brand tea infusions, and dust samples collected from the Erciyes University campus car park. The average fluoride concentration in 39 drinking waters was 0.21 mg L^{-1} (0.02--1.42 mg L^{-1}); the level of dissolved fluoride in the dust samples was 1.39 \pm 0.09 \mu g g^{-1}; the fluoride concentrations in liquors taken …
Determination Of Linear Alkylbenzene Sulphonates And Their Biodegradation Intermediates By Isocratic Rp-Hplc, Mehmet Akyüz, David J. Roberts
Determination Of Linear Alkylbenzene Sulphonates And Their Biodegradation Intermediates By Isocratic Rp-Hplc, Mehmet Akyüz, David J. Roberts
Turkish Journal of Chemistry
An HPLC method was developed to determine linear alkylbenzene sulphonates (LASs) and their biotransformation products sulphophenyl carboxylates by isocratic chromatography using two C_{18} columns in series. Solid-phase extraction with a (C_{18}) cartridge was employed to isolate LAS from sediment and sewage effluent samples. Sodium perchlorate and ammonium perchlorate were used as ion pair agents. The recovery of the compounds was 94% \pm 2 and 98% \pm 2 respectively for sediment and sewage effluent. It was demonstrated that it is possible to separate LAS compounds and their isomers and homologues using this system.
Electrothermal Atomic Absorption Spectrometric Determination Of Nickel After Its Flotation Enrichment By Iron(Iii) Hexamethylenedithiocarbamate, Trajce Stafilov, Gorica Pavlovska, Katarina Cundeva
Electrothermal Atomic Absorption Spectrometric Determination Of Nickel After Its Flotation Enrichment By Iron(Iii) Hexamethylenedithiocarbamate, Trajce Stafilov, Gorica Pavlovska, Katarina Cundeva
Turkish Journal of Chemistry
Abstract. Nanogram quantities of nickel were removed from 1 L samples of dilute aqueous solutions by coflotation. A mixture of hydrated iron(III) oxide (Fe_2O_3\( \cdot \)xH_2O) and iron(III) hexamethylene-dithiocarbamate (Fe(HMDTC)_3) served as collectors. After flotation separation from the mother liquor, the solid sublate containing nickel traces was dissolved and the analyte was determined by electrothermal atomic absorption spectrometry (ETAAS). All important parameters necessary for the successful collection of nickel were checked. The results of nickel ETAAS analysis in tap and spring waters were compared with inductively coupled plasma-atomic emis-sion spectrometric measurements (ICP-AES). The limit detection of nickel by the ETAAS …