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Full-Text Articles in Physical Sciences and Mathematics

Separation And Preconcentration Of Pb(Ii) And Cu(Ii) Ions Via Carrier Element-Free Coprecipitation Using An Acetohydrazide Derivative, Süreyya Oğuz Tümay, Murat Yazar, Duygu Özdeş, Hakan Bektaş, Celal Duran Jan 2016

Separation And Preconcentration Of Pb(Ii) And Cu(Ii) Ions Via Carrier Element-Free Coprecipitation Using An Acetohydrazide Derivative, Süreyya Oğuz Tümay, Murat Yazar, Duygu Özdeş, Hakan Bektaş, Celal Duran

Turkish Journal of Chemistry

A new method based on the combination of carrier element-free coprecipitation and flame atomic absorption spectrometric determination has been investigated for simultaneous separation and preconcentration of Pb(II) and Cu(II) ions in some environmental solid and liquid samples. The 2-{3-(4-methylbenzyl)-4-[2-(1H-indol-3-yl)ethyl]-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl} -N'-(phenylmethylene) acetohydrazide (MITA) was utilized as an organic coprecipitating agent without using a carrier element for coprecipitation of the analyte ions. The effects of experimental conditions including aqueous solution pH, MITA quantity, sample volume, standing time, and centrifugation rate and time were investigated in detail and optimized. The influences of some foreign ions were also evaluated on the quantitative recoveries of …


Biosorption Potential Of Surface-Modified Waste Sugar Beet Pulp For The Removal Of Reactive Yellow 2 (Ry2) Anionic Dye, Si̇bel Tunali Akar, Sema Çeli̇k, Di̇lek Tunç, Yasemi̇n Yeti̇moğlu Balk, Tamer Akar Jan 2016

Biosorption Potential Of Surface-Modified Waste Sugar Beet Pulp For The Removal Of Reactive Yellow 2 (Ry2) Anionic Dye, Si̇bel Tunali Akar, Sema Çeli̇k, Di̇lek Tunç, Yasemi̇n Yeti̇moğlu Balk, Tamer Akar

Turkish Journal of Chemistry

Tetra-$n$-butylammonium bromide modified sugar beet pulp (TBAB-SBP) with good biosorption and regeneration potential was prepared for removal of dye from contaminated solutions. The decolorization performance of TBAB-SBP was investigated using Reactive Yellow 2 (RY2) as a model dye. The characterization of the modified biosorbent was investigated by IR, SEM, zeta potential, and BET surface area analysis to discuss the decolorization mechanism. The effects of initial pH, biosorbent amount, contact time, dye concentration, and flow rate on the treatment process were examined. The experimental kinetic data were well predicted by the pseudo-second-order kinetic model and Langmuir isotherm with a maximum monolayer …


Synthesis And Evaluation Of A Novel N--P-Containing Oil-Based Fire-Retardant Plasticizer For Poly(Vinyl Chloride), Pu-You Jia, Guo-Dong Feng, Yun Hu, Yong-Hong Zhou Jan 2016

Synthesis And Evaluation Of A Novel N--P-Containing Oil-Based Fire-Retardant Plasticizer For Poly(Vinyl Chloride), Pu-You Jia, Guo-Dong Feng, Yun Hu, Yong-Hong Zhou

Turkish Journal of Chemistry

A novel N--P-containing soybean-oil-based fire-retardant plasticizer was synthesized using soybean oil methyl ester, 9,10-dihydro-9-oxa-phosphaphenanthrene-10-oxide (DOPO), and tris(2-hydroxyethyl) isocyanurate (THEIC). The structure was verified by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The blends were characterized by thermogravimetric analysis (TGA), FTIR spectrometry, scanning electron microscopy (SEM), and dynamic mechanical analysis (DMA). TGA showed that the thermal stability of the blends were acceptable. DMA indicated that the plasticizer had good plasticity for PVC. The limiting oxygen index (LOI) of the blends ranged from 21.3 to 29.6. The flammability and thermal stability of PVC/THEIC-DOPO-ESOME was better than that of …


Comparative Study For The Separation, Preconcentration, And Determination Of Copper And Cadmium In Real Samples By Using Two Different Ligands, Hami̇de Elvan Bayrak, Volkan Numan Bulut, Mehmet Tüfekçi̇, Hacer Bayrak, Celal Duran, Mustafa Soylak Jan 2016

Comparative Study For The Separation, Preconcentration, And Determination Of Copper And Cadmium In Real Samples By Using Two Different Ligands, Hami̇de Elvan Bayrak, Volkan Numan Bulut, Mehmet Tüfekçi̇, Hacer Bayrak, Celal Duran, Mustafa Soylak

Turkish Journal of Chemistry

Two new solid phase extraction methods have been developed for simultaneous separation and preconcentration of Cu(II) and Cd(II) in some food and environmental samples before their determination by flame atomic absorption spectrometry (FAAS). One of these methods is based on the absorption of the Cu(II) and Cd(II) complexes with [3-(cyanomethyl)-5-(4-methylphenyl)-4$H$-1,2,4-triazol-4-yl]carbamate (L1) and the other is based on the absorption of the Cu(II) and Cd(II) complexes with 4-(4-methylphenyl)-5-{[pyridine-4-yl-4$H$-1,2,4-triazole-3-yl)thio]methyl}-4$H$-1,2,4-triazole-3-thiol (L2) on Amberlite XAD-1180 resin. The metal complexes are retained on resin at pH 6.0 and eluted with 1.0 mol L$^{-1}$ HCl in acetone in both methods. After the optimum conditions were determined, …


Liquid State $^{15}$N Nmr Studies Of $^{15}$N Isotope Labeled Phthalocyanines, Armağan Atsay, Ahmet Gül, Makbule Koçak Jan 2016

Liquid State $^{15}$N Nmr Studies Of $^{15}$N Isotope Labeled Phthalocyanines, Armağan Atsay, Ahmet Gül, Makbule Koçak

Turkish Journal of Chemistry

$^{15}$N labeled soluble metallo- and metal-free phthalocyanines are described for the first time. The complexes were synthesized starting from phthalic anhydride derivatives using 98{\%} $^{15}$N enriched urea. The effects of the substitution pattern, aggregation, and coordinated metal on $^{15}$N chemical shifts in liquid state NMR were studied.


Wittig--Horner Reagents: Powerful Tools In The Synthesis Of 5-And 6-Heterocyclic Compounds; Shedding Light On Their Application In Pharmaceutical Chemistry, Rizk Elsayed Khidre, Wafaa Mahmoud Abdou Jan 2016

Wittig--Horner Reagents: Powerful Tools In The Synthesis Of 5-And 6-Heterocyclic Compounds; Shedding Light On Their Application In Pharmaceutical Chemistry, Rizk Elsayed Khidre, Wafaa Mahmoud Abdou

Turkish Journal of Chemistry

This paper reviews literature over 25 years' activity on phosphoryl carbanion reagents and shows that these compounds are powerful tools in organic chemistry. The main target of this review is to outline some of the reactive peculiarities that make this class of compounds powerful tools in the synthesis of 5- and 6-heterocyclic compounds and/or substituted heterocycle phosphor esters. The importance of these latter compounds in pharmacology is also discussed.


Enhanced Delivery Of Epirubicin By Polyoxometalate-Based Magnetic Nanocarriers: Controlled Drug Loading And Ph-Sensitive Drug Release, Ezzat Rafiee, Nasibeh Rahpeyma Jan 2016

Enhanced Delivery Of Epirubicin By Polyoxometalate-Based Magnetic Nanocarriers: Controlled Drug Loading And Ph-Sensitive Drug Release, Ezzat Rafiee, Nasibeh Rahpeyma

Turkish Journal of Chemistry

A series of polyoxometalate-based magnetic nanoparticles were developed as novel carriers for anticancer drugs. Characterization of the nanoparticles was done by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), wavelength dispersive X-ray (WDX), and laser particle size analyzer. Epirubicin (EPI) was selected as a model drug. EPI loading efficiency, EPI loading content, and EPI release profiles were studied. Drug loading was controlled using acid-base titration since H$^{+}$ was released during the loading process. Based on these investigations, an efficient EPI delivery system was introduced. It showed high EPI-loading capacity (35.2 wt.{\%}) and high EPI loading …


Investigation Of Long-Term Water Absorption Behavior Of Carbon Fabric Reinforced Epoxy Composites Containing Hydrophobic Nanosilica, Nurten Eki̇n, Mehmet Gali̇p İçduygu, Ahmet Gültek Jan 2016

Investigation Of Long-Term Water Absorption Behavior Of Carbon Fabric Reinforced Epoxy Composites Containing Hydrophobic Nanosilica, Nurten Eki̇n, Mehmet Gali̇p İçduygu, Ahmet Gültek

Turkish Journal of Chemistry

hydrophobic filler containing epoxy matrix composites was investigated by keeping them in distilled water for 9 months. Aerosil R812 (8 nm) and Aerosil R972 (12 nm) were utilized at 3{\%} and 5{\%} w/w filler to resin ratio and the resin/filler mixture was combined with 12-ply carbon fabric to get 15 $\times $ 15 cm samples. Samples were molded under a hot press and for each sample 50 test samples obtained by cutting them with a water jet. The obtained samples were characterized by TG, FTIR, and SEM. The effect of water absorption was evaluated by measuring percentage water absorption and …


Impregnation Of Different Ionic Liquids Onto Cationic Starch And Their Comparison In The Extraction Of Th(Iv), Eli̇f Ant Bursali, Serap Seyhan Bozkurt, Mürüvvet Yurdakoç Jan 2016

Impregnation Of Different Ionic Liquids Onto Cationic Starch And Their Comparison In The Extraction Of Th(Iv), Eli̇f Ant Bursali, Serap Seyhan Bozkurt, Mürüvvet Yurdakoç

Turkish Journal of Chemistry

Cationic starch (CS) was prepared by using epichlorohydrin (EPI) and 3-chloro-2-hydroxypropyltrimethy- lammonium chloride (CHPTMA) and ionic liquids (ILs) having different anionic groups [1-butyl-3-methyl imidazolium tetrafluoroborate (BMI$^{+}$BF$_{4}^{-})$, 1-butyl-3-methyl imidazolium bromide (BMI$^{+}$Br$^{-})$, 1-butyl-3-methyl imidazolium hexafluorophosphate (BMI$^{+}$PF$_{6}^{-})$, and 1-butyl-3-methyl imidazolium bis-[(trifluoromethyl)sulfonyl]imide (BMI$^{+}$ [(TF)$_{2}$N]$^{-})$] were impregnated onto CS. Thorium(IV) ions were preconcentrated by using IL impregnated CS. The effects of ILs were investigated for extraction of Th(IV) by CS and the results were compared. Th(IV) was preconcentrated with approximately 73{\%} sorption capacity by CS and increased up to 98{\%}--100{\%} for IL impregnated sorbents at pH 7.0. The sorption capacities of Th(IV) were 0.453 mmol …


Synthesis And Evaluation Of Novel $N,N'$-Disubstituted Benzimidazolium Bromides Salts As Antitumor Agents, Hasan Küçükbay, Akin Mumcu, Suat Teki̇n, Süleyman Sandal Jan 2016

Synthesis And Evaluation Of Novel $N,N'$-Disubstituted Benzimidazolium Bromides Salts As Antitumor Agents, Hasan Küçükbay, Akin Mumcu, Suat Teki̇n, Süleyman Sandal

Turkish Journal of Chemistry

Novel benzimidazolium bromides salts having (4-methoxyphenyl)ethyl, (phthalimide-2-yl)methyl, 4-nitro- benzyl, 2-phenylethyl, penthyl, or allyl groups were synthesized and their characterizations were conducted by $^{1}$H and $^{13}$C NMR and IR spectroscopic methods, and microanalysis. In vitro antitumor activities of the novel benzimidazole compounds (1-7) were determined by using ovarian (A2780) and prostate (PC-3) cancer cell lines. Antitumor properties of all compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. A time-dependent cell viability assay for the tested benzimidazole compounds was performed and the IC$_{50}$ values of the compounds were calculated after treatment for 24 and 48 h. Our results indicate that the tested …


An Efficient One-Pot, Three-Component Synthesis Of 6-Cyano-Hexahydro-4$H$-Thieno[3',2':5,6]Pyrimido[1,2-$A$]Quinoline-2-Carboxylates And Their Spiro Derivatives From $\Beta $-Enaminones, Said Ahmed Soliman Ghozlan, Doaa Mohmed Abdelmoniem, Amr Mohmed Abdelmoniem, Ismail Abdelshafy Abdelhamid Jan 2016

An Efficient One-Pot, Three-Component Synthesis Of 6-Cyano-Hexahydro-4$H$-Thieno[3',2':5,6]Pyrimido[1,2-$A$]Quinoline-2-Carboxylates And Their Spiro Derivatives From $\Beta $-Enaminones, Said Ahmed Soliman Ghozlan, Doaa Mohmed Abdelmoniem, Amr Mohmed Abdelmoniem, Ismail Abdelshafy Abdelhamid

Turkish Journal of Chemistry

A simple and efficient one-pot synthesis of novel thieno[3',2':5,6]pyrimido[1,2-a]quinoline-2-carboxylates (5a-d) and their spirooxindole derivatives (12a-d) was accomplished. Thus, the Michael addition reaction of the cyclic $\beta $-enaminone 3 with the corresponding $\alpha ,\beta $-unsaturated nitrile derivatives 4a-d in refluxing EtOH in the presence of piperidine afforded 5a-d in good yields. On the other hand, spirooxindole derivatives 12a-d were synthesized by the reaction of cyclic $\beta $-enaminone 3 with the corresponding 3-cyanomethylidene-2-oxoindoles 11a-d in refluxing EtOH.


Ecofriendly One-Pot Synthesis And Antiviral Evaluation Of Novel Pyrazolyl Pyrazolines Of Medicinal Interest, Sobhi Gomha, Magda Abdalla, Mohamad Abd El-Aziz, Nany Serag Jan 2016

Ecofriendly One-Pot Synthesis And Antiviral Evaluation Of Novel Pyrazolyl Pyrazolines Of Medicinal Interest, Sobhi Gomha, Magda Abdalla, Mohamad Abd El-Aziz, Nany Serag

Turkish Journal of Chemistry

Ethyl 3-acetyl-1,5-diphenyl-1$H$-pyrazole-4-carboxylate reacts with a variety of arylaldehydes by grinding method in the presence of a catalytic amount of sodium hydroxide at ambient temperature to give the respective chalcones. The latter compounds react also by grinding method with nitrogen nucleophiles such as hydrazine hydrate, phenylhydrazine, and thiosemicarbazide to afford the corresponding pyrazol-3-yl pyrazolines. A series of 6-pyrazolylpyrimidine-2-thione derivatives were prepared by reaction of the above chalcones with thiourea by grinding method in the presence of a catalytic amount of sodium hydroxide at room temperature. In addition, 7-pyrazolylpyridopyrimidine-3-thione was prepared by reaction of chalcone with 6-aminothiouracil. All the newly synthesized compounds …


Preparation And Characterization Of Zno/Mmt Nanocomposite For Photocatalytic Ozonation Of A Disperse Dye, Alireza Khataee, Murat Kiranşan, Semra Karaca, Samira Arefi- Oskoui Jan 2016

Preparation And Characterization Of Zno/Mmt Nanocomposite For Photocatalytic Ozonation Of A Disperse Dye, Alireza Khataee, Murat Kiranşan, Semra Karaca, Samira Arefi- Oskoui

Turkish Journal of Chemistry

ZnO was immobilized on the montmorillonite (MMT) to synthesize ZnO/MMT nanocomposite. Physicochemical properties of the as-synthesized nanocomposite were determined using X-ray diffraction, scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, N$_{2}$ adsorption/desorption, and point of zero charge pH (pH$_{pzc})$ analysis. The performance of the prepared ZnO/MMT nanocomposite was examined for the photocatalytic ozonation of Disperse Red 54 (DR54) and the highest decolorization efficiency (88.75{\%} after 60 min of reaction time) was the result for the mentioned process compared to adsorption, single ozonation, catalytic ozonation, and photolysis. The influence of various operational parameters including initial dye concentration, catalyst concentration, …


Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu Jan 2016

Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu

Turkish Journal of Chemistry

SiO$_{2}$ supported core@shell nanoparticles (CSNs) have recently attracted great attention due to their unique, tunable, optical, photocatalytic, and higher adsorption properties. In this study, SiO$_{2}$@CeO$_{2}$~CSNs were synthesized using a chemical precipitation technique and characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) analysis. XRD analysis showed that SiO$_{2\, }$particles were the core while CeO$_{2}$ particles were the shell. It was seen as a new band at 961 cm$^{-1}$ of the oxygen bridge between Si and Ce atoms from FT-IR results; SiO$_{2}$ and CSNs were spherical (0.5--0.6 $\mu $m) from SEM and …


Synthesis And Computational Studies Of New Metallo-Phthalocyanines Bearing Dibenzoxanthenes And Evaluation Of Their Optical Properties In Solution And Solid Pmma/Znpc/Al Nanocomposite Films, Ali Reza Karimi, Zeinab Jafarzadeh, Meysam Sourinia, Akbar Zendehnam, Azam Khodadadi, Zeinab Dalirnasab, Mohammad Solimannejad, Peyman Zolgharnein Jan 2016

Synthesis And Computational Studies Of New Metallo-Phthalocyanines Bearing Dibenzoxanthenes And Evaluation Of Their Optical Properties In Solution And Solid Pmma/Znpc/Al Nanocomposite Films, Ali Reza Karimi, Zeinab Jafarzadeh, Meysam Sourinia, Akbar Zendehnam, Azam Khodadadi, Zeinab Dalirnasab, Mohammad Solimannejad, Peyman Zolgharnein

Turkish Journal of Chemistry

New thermally stable metallo-phthalocyanines bearing dibenzoxanthenes as highly organo-solubilizing aromatic hydrocarbon substituents were successfully prepared by cyclotetramerization of corresponding phthalonitriles with anhydrous metal salts [Zn(CH$_{3}$COO)$_{2}$ and NiCl$_{2}$] in the presence of a catalytic amount of DBU in 2-(dimethylamino) ethanol. All of these phthalocyanines are soluble in some organic solvents such as DMF, DMSO, THF, CH$_{2}$Cl$_{2}$, and CHCl$_{3}$. Then we successfully prepared the poly(methyl methacrylate) (PMMA)/ZnPc/Al nanocomposite films by incorporating Al nanoparticles into a transparent PMMA/ZnPc matrix. The structure and morphology of nanocomposite films were studied using X-ray diffraction and scanning electron microscopy. The optical absorption spectra of PMMA/ZnPc/Al nanocomposite films …


Newly Synthesized Furanoside-Based Nhc Ligands For The Arylation Of Aldehydes, Serpi̇l Deni̇zalti, Fatma Çeti̇n Telli̇, Seli̇n Yildiran, Azi̇ze Yeşi̇m Salman, Beki̇r Çeti̇nkaya Jan 2016

Newly Synthesized Furanoside-Based Nhc Ligands For The Arylation Of Aldehydes, Serpi̇l Deni̇zalti, Fatma Çeti̇n Telli̇, Seli̇n Yildiran, Azi̇ze Yeşi̇m Salman, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

New furanoside-based NHC precursor salts (2) were synthesized using amino alcohols from the chloralose derivatives of glucose (a), galactose (b), and mannose (c). The novel compounds were fully characterized by $^{1}$H NMR, $^{13}$C NMR, and elemental analyses. The catalytic activities of these salts were tested in the arylation of aldehydes as catalysts that were generated in situ from [RhCl(COD)]$_{2}$. In addition, 2a was converted to the rhodium complex 3a in order to compare the results obtained in situ. The newly synthesized compounds were very efficient in terms of yield; nevertheless they did not exhibit a chiral induction.


Speciation Of Inorganic Selenium By Solid Phase Extraction Using Nanozirconium Oxide/Boron Oxide Composite Material, Hakan Erdoğan, Özcan Yalçinkaya, Ali̇ Rehber Türker Jan 2016

Speciation Of Inorganic Selenium By Solid Phase Extraction Using Nanozirconium Oxide/Boron Oxide Composite Material, Hakan Erdoğan, Özcan Yalçinkaya, Ali̇ Rehber Türker

Turkish Journal of Chemistry

The speciation and preconcentration of selenium were carried out by solid phase extraction using nanozirconium oxide/boron oxide (ZrO$_{2}$/B$_{2}$O$_{3})$. Electrothermal atomic absorption spectrometry (ETAAS) was used for detection. This preconcentration and/or speciation method depends on the retention of Se(IV) ions selectively as its ammonium pyrrolidine dithiocarbamate (APDC) complex on the sorbent. The effects of pH, flow rate, and volume of sample solution and eluent type were investigated for determining the optimum preconcentration and speciation conditions. The effects of other ions that may interfere with the determination and speciation of selenium were also investigated. Moreover, the analytical performance criteria of the method …


Synthesis, ($E)$/($Z)$-Isomerization, And Dna Binding, Antibacterial, And Antifungal Activities Of Novel Oximes And $O$-Substituted Oxime Ethers, Hati̇ce Başpinar Küçük, Ayşe Sergüzel Yusufoğlu, Leyla Açik, Betül Aydin, Leyla Arslan Jan 2016

Synthesis, ($E)$/($Z)$-Isomerization, And Dna Binding, Antibacterial, And Antifungal Activities Of Novel Oximes And $O$-Substituted Oxime Ethers, Hati̇ce Başpinar Küçük, Ayşe Sergüzel Yusufoğlu, Leyla Açik, Betül Aydin, Leyla Arslan

Turkish Journal of Chemistry

A series of novel positional oximes (2a-2d), $O$-methyl oxime ethers (3a-3d), and $O$-benzyl oxime ethers (4a-4d) were synthesized in high yields starting from their corresponding methyl 3-, 4-, 6-, and 13-keto tetradecanoates. The synthesized compounds were characterized by $^{1}$H NMR, $^{13}$C NMR, FT-IR, mass, and elemental analyses for their structures and $(E)$/$(Z)$ isomerizations. Their DNA binding abilities were investigated in vitro by agarose gel electrophoresis. The antibacterial and antifungal activities were tested also in vitro against eleven bacterial strains and three fungal strains. The relationship between the structure and the mentioned biological activities was discussed. Compound 2a showed good antibacterial …


Synthesis Of New Hexahydro-1h-Isoindole-1,3(2h)-Dione Derivatives From 2-Ethyl/Phenyl-3a,4,7,7a-Tetrahydro-1h-Isoindole-1,3-(2h)-Dione, Ayşe Tan, Bi̇rgül Koç, Nurhan Ki̇shali, Ertan Şahi̇n, Yunus Kara Jan 2016

Synthesis Of New Hexahydro-1h-Isoindole-1,3(2h)-Dione Derivatives From 2-Ethyl/Phenyl-3a,4,7,7a-Tetrahydro-1h-Isoindole-1,3-(2h)-Dione, Ayşe Tan, Bi̇rgül Koç, Nurhan Ki̇shali, Ertan Şahi̇n, Yunus Kara

Turkish Journal of Chemistry

A new and appropriate synthesis for hexahydro-1H-isoindole-1,3(2H)-dione derivatives has been developed starting from 3-sulfolene. The epoxidation of 2-ethyl/phenyl-3a,4,7,7a-tetrahydro-1H-isoindole-1,3-(2H)-dione and then the opening of the epoxide with nucleophiles gave hexahydro-1H-isoindole-1,3(2H)-dione derivatives. Amino and triazole derivatives of hexahydro-1H-isoindole-1,3(2H)-dione were synthesized from the formed product by the opening reaction of the epoxide with sodium azide. Hydroxyl analogues were obtained from cis-hydroxylation of 2-ethyl/phenyl-3a,4,7,7a-tetrahydro-1H-isoindole-1,3-(2H)-dione. The hydroxyl groups were converted to acetate.


Speciation Of Trace Metals And Metalloids By Solid Phase Extraction With Spectrometric Detection: A Critical Review, Ali̇ Rehber Türker Jan 2016

Speciation Of Trace Metals And Metalloids By Solid Phase Extraction With Spectrometric Detection: A Critical Review, Ali̇ Rehber Türker

Turkish Journal of Chemistry

Considerable interest is continuing to be shown in the speciation of metals, metalloids, and organometals due to the dependence of their toxicity and mobility on their chemical form. This review focuses on the speciation analysis of metals, metalloids, and organometals by solid phase extraction before spectrometric detection, and all aspects of analytical speciation such as determination of oxidation states and organometallic compounds. Some applications of speciation of metals and metalloids are also presented and discussed in this review. Fractionation, which is used sometimes as speciation, and chromatographic detection are not discussed. This review covers approximately the last four years (2012-March …


Latest Trends, Green Aspects, And Innovations In Liquid-Phase--Based Microextraction Techniques: A Review, Erkan Yilmaz, Mustafa Soylak Jan 2016

Latest Trends, Green Aspects, And Innovations In Liquid-Phase--Based Microextraction Techniques: A Review, Erkan Yilmaz, Mustafa Soylak

Turkish Journal of Chemistry

Liquid-phase microextraction (LPME) methods including single-drop microextraction (SDME), hollow-fiber LPME (HF-LPME), and dispersive liquid-liquid microextraction (DLLME) have in the very short time since their invention grabbed the attention of scientists. Up to now, LPME methods have shown important innovations for the extraction and preconcentration of both inorganic and organic trace analytes from different matrices. These LPME methods offer unique advantages such as high preconcentration factor for target analytes in a single step, low cost, simplicity, excellent preconcentration capability, sample cleanup and integration of steps, and combined use with almost every analytical measurement technique. We describe the milestones and the combined …


Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman Jan 2016

Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman

Turkish Journal of Chemistry

Hexavalent chromium, Cr(VI), is a highly toxic species, while trivalent chromium, Cr(III), is an essential trace element for humans and other organisms. In the present work, a simple, rapid, and efficient procedure for water treatment of Cr(VI) is described. Active carbon (AC) was chemically treated with HCl and NaOH for the formation of surface modified Acidic-AC and Basic-AC sorbents, respectively. In addition, AC sorbent was treated with HNO$_{3}$ as an oxidizing agent and sodium sulfite as a reducing agent for the formation of Ox-AC and Rd-AC sorbents, respectively. The modified AC sorbents were tested to identify their potential applications in …


Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova Jan 2016

Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova

Turkish Journal of Chemistry

This study is focused on the synthesis of chromate anion imprinted sorbent supported on silica gel for nonchromatographic Cr speciation in surface waters. The preparation procedure is based on grafting of 3-methyl-1-trimethoxysilylpropylimidazolium, preliminarily coordinated to CrO$_{4}^{2-}$ as a template ion, onto the surface of silica gel. Sorption and desorption characteristics of surface-imprinted sorbent toward Cr(III) and Cr(VI) were examined by batch solid-phase extraction. An excellent separation of Cr(VI), selectively retained on the sorbent, from Cr(III) remained in the solution, was achieved at pH 2-3 for 20 min. A freshly prepared mixture of ascorbic acid and nitric acid was selected as …


Spectrophotometric Determination Of Mercury Using Vortex-Assisted Liquid-Liquid Microextraction, Tatiana Antolova, Serhii Zaruba, Jana Sandrejova, Livia Kocurova, Andriy B. Vishnikin, Yaroslav Bazel, Vasil Andruch, Ioseph S. Balogh Jan 2016

Spectrophotometric Determination Of Mercury Using Vortex-Assisted Liquid-Liquid Microextraction, Tatiana Antolova, Serhii Zaruba, Jana Sandrejova, Livia Kocurova, Andriy B. Vishnikin, Yaroslav Bazel, Vasil Andruch, Ioseph S. Balogh

Turkish Journal of Chemistry

A novel method for the determination of mercury(II) is suggested. The procedure is based on the formation of an ion associate between the bromide complex of Hg(II) and Astrazon Red 6B dye and vortex-assisted liquid-liquid microextraction of the ion associate formed, with subsequent spectrophotometric detection. The variables that affect the procedure, such as pH, the concentration of ligand and dye, the type and volume of extraction solvent, and the rate and time of vortex mixing, were optimized. Under optimum conditions (pH 2.0, 0.01 mol L$^{-1}$ KBr, 2 $\times $ 10$^{-4}$ mol L$^{-1}$ AR6B, 50 $\mu $L of the extraction mixture …


Development Of A Method For The Determination Of Cadmium Levels In Seawater By Flame Atomic Absorption Spectrometry Using An Online Cloud-Point Extraction System, Rafael Vasconcelos Oliveira, Uelber Silva Vieira, Mardson Vasconcelos Maciel, Thais Souza Neri, Graziele Santos Sales, Rebeca Moraes Menezes, Valfredo Azevedo Lemos Jan 2016

Development Of A Method For The Determination Of Cadmium Levels In Seawater By Flame Atomic Absorption Spectrometry Using An Online Cloud-Point Extraction System, Rafael Vasconcelos Oliveira, Uelber Silva Vieira, Mardson Vasconcelos Maciel, Thais Souza Neri, Graziele Santos Sales, Rebeca Moraes Menezes, Valfredo Azevedo Lemos

Turkish Journal of Chemistry

A new system was developed for the preconcentration and determination of cadmium levels in water following online cloud-point extraction and analysis by flame atomic absorption spectrometry. The method uses cloud-point extraction of the complex formed between Cd(II) ions and the reagent 2-(5-bromo-2'-thiazolylazo)-$p$-cresol (Br-TAC) using Triton X-114 as a surfactant. The main steps of the procedure, extraction, filtration, and detection were conducted online. Parameters that influence the experimental conditions of online preconcentration systems were examined, including pH, concentration of reagent and surfactant, and flow of sample and eluent. The limit of detection of the method is 0.2 $\mu $g L$^{-1}$. The …